JP2012192767A - Hydraulic brake system for vehicle - Google Patents

Abstract

A vehicle hydraulic brake system capable of suppressing fluctuations in supply pressure due to operation of an ABS valve device during execution of ABS control is provided.
An ABS control is configured such that a supply current to a pressure increasing solenoid valve and a pressure reducing solenoid valve included in a hydraulic pressure source device is controlled based on a target supply pressure P ^* determined in accordance with a brake operation. For example, the correction pressure α _p is set to the target supply pressure P ^* corresponding to the brake operation so that the valve opening pressure of the pressure-increasing solenoid valve is higher than when it is not executed. In addition, by correcting the supply current to the pressure increasing solenoid valve and the pressure reducing solenoid valve based on the corrected target supply pressure P ^* + α _p , the pressure increasing solenoid valve is controlled. The current supplied is configured to be changed. Since the differential pressure between the hydraulic pressure of the high pressure source and the supply pressure Pr is reduced during the execution of ABS, fluctuations in the supply pressure due to the operation of the ABS valve device can be suppressed.
[Selection] Figure 9

Description

  The present invention relates to a vehicular hydraulic brake system including a hydraulic brake device that operates by hydraulic pressure of hydraulic fluid to apply braking force to wheels.

  Conventionally, as a hydraulic brake system mounted on a vehicle, a system that generates a braking force based on hydraulic fluid supplied from a hydraulic pressure source device without depending on an operation force applied to a brake operation member by a driver, A so-called electronically controlled brake system is known. In such a system, as in the system described in the following patent document, the hydraulic pressure source device supplies the hydraulic pressure source device by controlling the supply current to the pressure increasing solenoid valve and the pressure reducing solenoid valve. It is possible to change the supply pressure, which is the hydraulic pressure of the working fluid, to be controllable, and to generate an appropriate braking force according to the brake operation by the driver. In addition, an ABS valve device is provided between the hydraulic pressure source device and the brake device in order to cope with wheel locking, skidding, and the like.

JP 2009-61816 A JP 2009-292176 A JP 2007-137281 A

  When ABS control is executed in a system including a hydraulic pressure source device and an ABS valve device as in the brake system described in the above-mentioned patent document, the brake that is the hydraulic pressure of the brake device is activated by the operation of the ABS valve device. The pressure is increased, decreased and maintained repeatedly. In other words, the ABS valve device repeatedly switches between the state where the hydraulic fluid supply from the hydraulic pressure source device is allowed to be supplied to the brake device and the state where the hydraulic fluid is shut off, and the supply pressure fluctuates accordingly. There's a problem. Further, when the brake pressure is increased, the state where the supply of hydraulic fluid from the hydraulic pressure source device is allowed to be interrupted and the state where the hydraulic fluid is blocked are repeatedly switched at shorter time intervals in order to control the pressure increase gradient. As a result, the supply pressure fluctuates in a vibration manner, and there is a problem that the supply pressure is not stable. And the hydraulic brake system described in said patent document is comprised so that execution of the control for coping with the fluctuation | variation of the supply pressure by the action | operation of an ABS valve apparatus is possible. The present invention has been made to cope with fluctuations in supply pressure due to operation of the ABS valve device, and in particular, fluctuations in supply pressure due to operation of the ABS valve device during execution of ABS control can be suppressed. It is an object to provide a hydraulic brake system for a vehicle.

  In order to solve the above-described problem, the hydraulic brake system for a vehicle according to the present invention is based on the target supply pressure determined according to the brake operation, to the pressure increasing solenoid valve and the pressure reducing solenoid valve of the hydraulic pressure source device. When the ABS control is being executed, the pressure increasing electromagnetic valve is increased so that the valve opening pressure of the pressure increasing solenoid valve is higher when the ABS control is being executed. It is configured to change the current supplied to the valve.

  In the vehicle hydraulic brake system of the present invention, the actual supply pressure is increased by changing the supply current so that the valve opening pressure of the pressure increasing solenoid valve is increased. That is, according to the system of the present invention, the difference between the hydraulic pressure of the high pressure source and the supply pressure is reduced during the ABS execution. It is possible to suppress an increase in supply pressure when the supply of the hydraulic fluid is interrupted.

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which some constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

  In each of the following items, item (1) corresponds to claim 1, and the technical features described in item (11) are added to item (1) in item (2), item (12) in item (2). ) Added with the technical features described in claim 3 is added to claim 3, and any one of claims 1 to 3 added with the technical features described in claim (14) is added to claim 4. The technical feature according to (15) is added to claim 4, and the technical feature according to claim (16) is added to claim 4 or claim 5. The technical feature described in (17) is added to claim 6, the technical feature described in (17) is added to claim 6, and the technical feature described in (18) is added to any one of claims 1 to 7. Is obtained by adding the technical features described in (5) to any one of claims 1 to 8. The technical feature according to claim 9 is added with the technical feature according to claim 6 to claim 9, and the technology according to claim 3 is added to any one of claims 1 to 10. The technical feature is added to claim 11, the technical feature described in (21) is added to any one of claims 1 to 11 in claim 12, and in claim 12 ( The technical features described in the item (22) correspond to the items (13), respectively.

(1) a brake operation member operated by a driver;
A brake device that is provided corresponding to the wheel and operates by the hydraulic pressure of the hydraulic fluid supplied to the wheel to apply a braking force to the wheel;
It is a device that supplies hydraulic fluid with regulated hydraulic pressure to the brake device, and (a) a high pressure source that generates a high hydraulic pressure, and (b) the valve opening pressure is changed according to the current supplied to itself. A solenoid valve for increasing the pressure of the hydraulic fluid to be supplied; and (c) a solenoid valve for reducing the pressure of the hydraulic fluid to be supplied by changing the valve opening pressure according to the current supplied to itself. A hydraulic pressure source device,
An ABS valve device which is provided between the hydraulic pressure source device and the brake device and is operated when performing ABS control for coping with locking of the wheel;
(A) a target supply pressure determination unit that determines a target supply pressure that is a target of a supply pressure that is a hydraulic pressure of hydraulic fluid supplied by the hydraulic pressure source device based on an operation of the brake operation member; ) Based on the target supply pressure, a supply pressure control unit that controls a supply current to the pressure increasing solenoid valve and the pressure reducing solenoid valve of the hydraulic pressure source device; and (C) to execute the ABS control An ABS control execution unit for controlling the ABS valve device; and (D) when the ABS control is executed by the ABS control execution unit, the opening of the pressure-increasing solenoid valve is compared with a case where the ABS control is not executed. A vehicle hydraulic brake system comprising: a control device having an ABS supply current changing unit that changes a current supplied to the pressure increasing solenoid valve so that the valve pressure increases.

  The vehicle hydraulic brake system including the hydraulic pressure source device and the ABS valve device as described above allows the supply of hydraulic fluid from the hydraulic pressure source device to the brake device during normal braking. The supply pressure is controlled by controlling the pressure increasing solenoid valve and the pressure reducing solenoid valve of the hydraulic pressure source device, so that the brake pressure that is the hydraulic pressure of the brake device (if the brake device has a wheel cylinder, the wheel cylinder pressure Is controlled in accordance with the brake operation.

  On the other hand, when the ABS control for coping with the wheel lock is executed, the operation of the ABS valve device is controlled, and the supply of the hydraulic fluid from the hydraulic pressure source device to the brake device is allowed and the hydraulic pressure of the brake device is set. A pressure increasing mode for increasing a certain brake pressure, a pressure reducing mode for prohibiting the supply of hydraulic fluid from the hydraulic pressure source device to the brake device and allowing the flow of hydraulic fluid to the low pressure source to reduce the brake pressure; The holding mode for holding the brake pressure by prohibiting both the supply of the hydraulic fluid from the pressure source device to the brake device and the flow of the hydraulic fluid to the low pressure source is repeatedly realized. In other words, by switching between a state in which the supply of hydraulic fluid from the hydraulic pressure source device to the brake device is allowed and a state in which the hydraulic fluid is shut off, specifically speaking, by opening and closing an ABS holding valve included in the ABS valve device that switches between these states. There is a problem that the supply pressure fluctuates. Further, in the above pressure increasing mode, in order to control the pressure increasing gradient of the brake pressure, the state where the supply of hydraulic fluid from the hydraulic pressure source device is allowed and the state where it is shut off, that is, the open / close state of the ABS holding valve May be repeatedly switched at shorter time intervals. Due to the control of the ABS holding valve, there is a problem that the supply pressure fluctuates and the supply pressure is not stable. In particular, in the ABS control, the supply pressure may be used to control the brake pressure increase gradient in the above-described pressure increase mode. If the supply pressure is not stable, the target pressure increase gradient is realized. It becomes difficult. That is, during the ABS control, the supply pressure is not stable, which causes a problem that the stop distance is extended.

  In the vehicle hydraulic brake system described in this section, the “hydraulic pressure source device” is controlled by the “supply pressure control unit” within a range having a certain margin with respect to the target supply pressure, for example, at normal times. The supply current of the pressure increasing solenoid valve is controlled so that the valve opening pressure of the pressure increasing solenoid valve becomes the lower limit value of the range so that the supply pressure falls, and the valve opening pressure of the pressure reducing solenoid valve is within the range. It is possible to configure so that the supply current of the pressure reducing solenoid valve is controlled to be the upper limit value. Incidentally, the valve opening pressure of the pressure increasing solenoid valve is the supply pressure that is the pressure on the outflow side when all the forces acting on the valve body of the solenoid valve are balanced, and the valve opening of the pressure reducing solenoid valve The pressure refers to a supply pressure that is a pressure on the inflow side in a state where all the forces acting on the valve body of the electromagnetic valve are balanced.

  The vehicle hydraulic brake system described in this section supplies the pressure increasing solenoid valve so that the valve opening pressure of the pressure increasing solenoid valve is higher than normal when the ABS control is executed. The current is changed. That is, the valve opening pressure of the pressure increasing solenoid valve is increased, the difference between the valve opening pressure and the actual supply pressure is increased, and the supply flow rate from the high pressure source to the brake device is increased. As a result, for example, when there is a relatively large difference between the actual supply pressure and the target supply pressure at the start of execution of ABS control, the supply pressure can be quickly increased.

  In other words, the valve is not closed unless the supply pressure is higher than normal, and the supply pressure is raised above the target supply pressure. Therefore, since the difference between the hydraulic pressure of the high pressure source and the supply pressure is reduced, fluctuations in the supply pressure due to the operation of the ABS valve device can be suppressed. More specifically, when the ABS valve device shifts from the pressure increasing mode in the ABS control to the pressure reducing mode, or when the ABS holding valve of the ABS valve device is closed due to control of the pressure increasing gradient in the pressure increasing mode. Even if it exists, since the difference between the hydraulic pressure of the high pressure source and the supply pressure is small, the increasing gradient of the supply pressure becomes gentle. In addition, this can reduce the frequency of opening the pressure reducing solenoid valve. Therefore, the system described in this section can stabilize the supply pressure during ABS execution. As described above, in the ABS control, the supply pressure may be used to control the pressure increase gradient of the brake pressure in the pressure increase mode. According to the aspect of this section, since it is possible to stabilize the supply pressure in an increased state, it is possible to realize an appropriate pressure increase gradient in the pressure increase mode and efficiently apply the braking force to the vehicle. Is possible.

  Incidentally, in order to maintain the supply pressure at a high level, the supply pressure to the pressure reducing solenoid valve is set so that the valve opening pressure of the pressure reducing solenoid valve is higher than that controlled by the supply pressure control unit. It is desirable to change the current as well. In the aspect described in this section, the method of changing the supply current to the pressure increasing solenoid valve and the pressure reducing solenoid valve is not limited to the aspect of directly changing the target supply current, and will be described in detail later. A mode in which the supply current is changed by correcting the target supply pressure may be employed. The magnitude of changing the supply current will be described in detail later, but can be determined based on various indicators.

  The “ABS valve device” described in this section may be any structure that can increase or decrease the brake pressure, which is the pressure of the hydraulic fluid supplied to the brake device, in order to cope with wheel locking, skidding, idling, etc. An ABS holding valve that can switch between allowing and disabling the hydraulic fluid supplied by the hydraulic pressure source device to the brake device, and allowing the hydraulic fluid supplied to the brake device to flow out to the low pressure source An ABS pressure-reducing valve that can be switched between a state to be performed and a state to be prohibited. The ABS holding valve is opened and the ABS pressure-reducing valve is closed, whereby the brake pressure is increased. The brake pressure can be reduced by closing the valve and opening the ABS pressure reducing valve.

(2) In the pressure increasing solenoid valve, the larger the current supplied to itself, the higher the valve opening pressure,
The ABS supply current changing unit is configured to increase the current supplied to the pressure-increasing solenoid valve when the ABS control is being executed, compared to when the ABS control is not being executed (1) The vehicle hydraulic brake system according to the item.

  The aspect described in this section is limited to a structure in which the pressure-increasing electromagnetic valve is closed in a state where no current is supplied.

(3) The ABS supply current changing unit is
When the ABS control is executed, the current supplied to the pressure reducing solenoid valve is also changed so that the valve opening pressure of the pressure reducing solenoid valve becomes higher than when the ABS control is not executed. The vehicle hydraulic brake system described in (1) or (2).

(4) The pressure reducing solenoid valve is assumed to have a higher valve opening pressure as the current supplied thereto decreases.
The ABS supply current changing unit is configured to reduce the current supplied to the pressure reducing solenoid valve when the ABS control is being executed compared to when the ABS control is not being executed (3) The vehicle hydraulic brake system according to the item.

  In the modes described in the above two items, the supply current to the pressure reducing solenoid valve is also changed. As described above, the modes of the above two terms are desirable modes for maintaining the supply pressure higher than the target supply pressure. The latter mode is limited to a structure in which the pressure reducing electromagnetic valve is closed in a state where no current is supplied.

(5) The ABS supply current changing unit is
When the ABS control is being executed, the target supply pressure determined by the target supply pressure determination unit is corrected to be higher than the target supply pressure, and the supply pressure control unit corrects the target supply pressure. The current supplied to the pressure-increasing solenoid valve is changed by allowing the supply current to the pressure-increasing solenoid valve and the pressure-reducing solenoid valve to be controlled based on (1) to (4) The hydraulic brake system for a vehicle according to any one of items.

  In the aspect described in this section, in order to change the supply current to the pressure increasing solenoid valve, the supply pressure targeted by the supply pressure control unit is set to a value higher than the target supply pressure determined by the target supply pressure determination unit. Is configured to change. In the aspect of this section, the valve opening pressure of the pressure reducing solenoid valve is also increased. The aspect of this section can also be considered as one aspect of the aspect described above, in which the current supplied to the pressure reducing solenoid valve is also changed so that the valve opening pressure of the pressure reducing solenoid valve is increased.

(6) The ABS supply current changing unit is
The vehicle hydraulic brake system according to (5), configured to prohibit a change in current supplied to the pressure increasing solenoid valve when the supply pressure exceeds the target supply pressure corrected by itself. .

  In the aspect described in this section, for example, when the supply pressure exceeds the corrected target supply pressure, the target supply pressure in the supply pressure control is returned to the original target supply pressure determined by the target supply pressure determination unit. It can be constituted as follows. According to the aspect of this section, the increased supply pressure is reduced, and overshoot of the supply pressure can be suppressed.

(7) The supply pressure control unit
When the supply pressure becomes equal to or lower than a pressure increase threshold value that is lower than the target supply pressure by a first setting difference, a current large enough to open the pressure increase solenoid valve is continuously supplied to the pressure increase solenoid valve. And supplying a current to the pressure reducing solenoid valve so that the pressure reducing solenoid valve is opened when the supply pressure is equal to or higher than a pressure reduction threshold value higher than the target supply pressure by a second set difference. The vehicle hydraulic brake system according to any one of (1) to (6), wherein the supply pressure is kept between the pressure increase threshold and the pressure decrease threshold by continuing.

  The system described in this section has a method for controlling the supply pressure, and is configured to continue supplying a so-called valve opening current to the two electromagnetic linear valves. In the aspect of this section, the valve opening pressure of the pressure increasing solenoid valve is set as the pressure increase threshold value, and the valve opening pressure of the pressure reducing solenoid valve is set as the pressure decrease threshold value. That is, when the supply pressure falls below the pressure increase threshold, the pressure increasing solenoid valve is mechanically opened to increase the pressure, and when the supply pressure exceeds the pressure reduction threshold, the pressure reducing solenoid valve is mechanically opened to reduce the pressure. Configured to do. Therefore, the supply pressure is controlled to be within the range where the valve opening pressure of the pressure increasing solenoid valve is the lower limit value and the valve opening pressure of the pressure reducing solenoid valve is the upper limit value. Note that the “first setting difference” and the “second setting difference” described in this section are not limited to positive values, but also include 0 and negative values. In other words, the “pressure increase threshold value” and the “pressure reduction threshold value” described in this section may be a value higher than the target supply pressure, a lower value, or the same height as the target supply pressure. Good. However, it is desirable that the depressurization threshold is set higher than the pressure increase threshold.

  The “target supply pressure” described in this section is not limited to the target supply pressure determined by the target supply pressure determination unit. That is, when the aspect of this section is combined with the above-described aspect of correcting the target supply pressure, the “target supply pressure” described in this section is the target supply pressure corrected by the ABS supply current changing unit. It may become.

(8) The supply pressure control unit
When the supply pressure is equal to or lower than the pressure increase threshold value, a current component having such a magnitude as to open the pressure increasing solenoid valve and a difference between the supply pressure and the target supply pressure A current that is added to the current component is supplied to the pressure-increasing solenoid valve, and when the supply pressure is equal to or greater than the pressure-reducing threshold, the pressure-reducing solenoid valve is opened in that case. The vehicle hydraulic brake system according to (7), wherein a current obtained by adding a current component and a current component corresponding to a difference between the supply pressure and the target supply pressure is supplied to the pressure reducing solenoid valve.

  The system described in this section is configured such that feedback control is performed when the supply pressure deviates from the target range in the supply pressure control. The “current component corresponding to the difference between the supply pressure and the target supply pressure” described in this section is, for example, a current component proportional to the difference between the supply pressure and the target supply pressure, that is, the supply pressure and the target supply pressure. The larger the difference, the larger the difference. According to the aspect of this section, it is possible to quickly eliminate the deviation between the supply pressure and the target supply pressure. In addition, when the aspect of this section is combined with the above-described aspect of correcting the target supply pressure, a current component corresponding to the difference between the corrected target supply pressure and the supply pressure is added. Since the flow rate can be increased, it is particularly effective when there is a relatively large difference between the actual supply pressure and the target supply pressure at the start of execution of the ABS control as described above.

(9) The vehicle hydraulic brake system is
A fluid pressure detector provided between the fluid pressure source device and the ABS valve device for detecting the fluid pressure of the working fluid;
The vehicle hydraulic brake system according to any one of (1) to (8), wherein the control device is configured to regard the hydraulic pressure detected by the hydraulic pressure detector as the supply pressure. .

  For example, consider a case where the brake system includes a plurality of brake devices, and ABS control is started in ones except for at least one of them. While the hydraulic pressure of the brake device for which ABS control has been executed increases with the supply pressure, the pressure increase gradient of the hydraulic pressure of the brake device for which ABS control has not been executed is controlled relatively gently by the ABS valve device. When all the ABS holding valves corresponding to the brake device for which the ABS control is being executed are closed, the hydraulic pressure detected by the hydraulic pressure detector is the hydraulic pressure of the brake device for which the ABS control is being executed. Is not reflected, and the hydraulic pressure of the brake device in which the ABS control is not executed is detected, and shows a relatively high value. That is, the difference between the target supply pressure and the supply pressure detected by the hydraulic pressure detector is reduced, and the ABS control is executed even when the supply pressure control unit adds the current component of the feedback control described above. There is a risk that the amount of hydraulic fluid supplied to the brake device is insufficient. Accordingly, since the supply flow rate is increased by changing the supply current to the pressure increasing solenoid valve by the supply current changing unit, the change of the supply current to the pressure increasing solenoid valve is particularly effective for the aspect of this section.

(11) The ABS supply current changing unit is
The current supplied to the pressure increasing solenoid valve is changed based on the difference between the target supply pressure determined by the target supply pressure determination unit and the brake pressure that is the hydraulic pressure of the brake device (1) to (1). The hydraulic brake system for a vehicle according to any one of items 9).

  The aspect described in this section is configured such that the amount of change in the supply current to the solenoid valve for pressure increase, the correction pressure in the above-described aspect, and the like are determined based on the difference between the target supply pressure and the brake pressure. Has been. The “brake pressure” described in this section is not limited to that directly detected by a sensor or the like, and may be estimated from other index values or the like. In a state where the ABS valve device is operating, the hydraulic pressure of the brake device for which the ABS control is being executed is different from the supply pressure, and is lower than the supply pressure. According to the aspect of this section, it is possible to change the current supplied to the pressure increasing solenoid valve to an appropriate magnitude according to the brake pressure. Incidentally, when the system includes a plurality of brake devices, the brake pressure is calculated by, for example, the maximum, minimum, and average values of the brake pressure of each of the plurality of brake devices and weighting each of them. Can be used.

(12) The ABS supply current changing unit is
A current supplied to the pressure-increasing solenoid valve is increased so that a valve opening pressure of the pressure-increasing solenoid valve becomes higher as a difference between the target supply pressure determined by the target supply pressure determining unit and the brake pressure is larger. The vehicle hydraulic brake system according to item (11) to be changed.

  The larger the difference between the target supply pressure and the brake pressure, the higher the supply pressure, so that the brake pressure can be effectively increased.

(13) The control device
A brake pressure estimator for estimating the brake pressure based on the operating status of the ABS valve device since the ABS valve device has started operating;
The ABS supply current changing unit is
Based on the difference between the estimated brake pressure, which is the brake pressure estimated by the brake pressure estimation unit, and the target supply pressure determined by the target supply pressure determination unit, the current supplied to the solenoid valve for pressure increase is The hydraulic brake system for a vehicle according to (11) or (12) to be changed.

  In general, as the brake pressure, the detection value of the hydraulic pressure detector described above is used, and when the ABS valve device is not operating, the brake pressure is the same as the supply pressure. The detected value is used as the brake pressure. However, when the ABS valve device is operating, the hydraulic pressure of the brake device for which the ABS control is being executed is different from the detection value of the hydraulic pressure detector. The operation status of the ABS valve device, for example, the operation history of each of the ABS holding valve and the ABS pressure reducing valve described above, specifically, the opening of the ABS holding valve and the ABS pressure reducing valve after the ABS valve device started to operate. It is possible to calculate the amount of change in brake pressure based on the valve time or the like. Therefore, the amount of change in the brake pressure calculated based on the operation history of each of the ABS holding valve and the ABS pressure reducing valve is taken into consideration with respect to the supply pressure immediately before the ABS valve device is operated. It is possible to appropriately estimate the brake pressure. According to the aspect described in this section, since the brake pressure estimated as described above is used, the supply current to the pressure increasing solenoid valve can be changed to an appropriate magnitude.

(14) The ABS supply current changing unit is
Estimating the required amount of hydraulic fluid to be supplied to the brake device, and changing the current supplied to the pressure increasing solenoid valve based on the required amount of fluid (1) to (13) The hydraulic brake system for vehicles as described in any one of these.

(15) The ABS supply current changing unit is
The vehicle hydraulic brake system according to item (14), wherein the current supplied to the pressure increasing solenoid valve is changed so that the valve opening pressure of the pressure increasing solenoid valve becomes higher as the required amount of fluid increases.

  The modes described in the above two sections are configured to estimate the amount of hydraulic fluid required by the brake device, in other words, the required flow rate from the high pressure source to the brake device. During the execution of the ABS control, the ABS valve device sometimes reduces and maintains the hydraulic pressure of the brake device, and at that time, it is not necessary to receive the supply of hydraulic fluid. Therefore, according to the modes described in the above two items, it is possible to increase the supply pressure only when the brake pressure needs to be increased. In addition, according to the aspects described in the above two items, it is possible to realize an appropriate pressure increase gradient in the pressure increase mode of the ABS control while ensuring followability to the target supply pressure.

  The “necessary flow rate” described in the above two terms can be estimated based on, for example, the difference between the current brake pressure and the target brake pressure. For example, a wheel cylinder included in the brake device has a predetermined relationship between the brake pressure and the amount of hydraulic fluid, and the necessary flow rate can be estimated in consideration of the relationship. In addition, the target brake pressure is controlled so as to achieve the target pressure increase gradient in the brake device in which the ABS control is executed, so that the current brake pressure is determined based on the pressure increase gradient. Can be determined from.

(16) The vehicle hydraulic brake system includes a plurality of brake devices each corresponding to the plurality of wheels, each of which is the brake device,
The ABS supply current changing unit is
The required fluid amount of each of the plurality of brake devices is estimated, and the current supplied to the pressure increasing solenoid valve is changed based on the total required fluid amount of each of the plurality of brake devices (14) or The hydraulic brake system for a vehicle according to item (15).

  In the aspect described in this section, there are some brake apparatuses that do not execute ABS control, and some that maintain and reduce the brake pressure even while ABS control is being executed. Taking this into consideration, the supply current to the pressure increasing solenoid valve is determined. Therefore, according to the aspect of this section, it is possible to suppress overshoot of supply pressure and excessive supply to those for which ABS control is not executed.

(17) The ABS supply current changing unit is
When the ABS valve device cuts off the supply of hydraulic fluid to all of the plurality of brake devices, the valve opening pressure of the pressure-increasing solenoid valve increased by itself and determined by the target supply pressure determining unit The vehicle hydraulic brake system according to item (16), wherein a pressure difference from the valve opening pressure of the pressure increasing solenoid valve determined with respect to the target supply pressure is prohibited from decreasing.

  When the ABS valve device cuts off the supply of hydraulic fluid to all of the plurality of brake devices, the required flow rate becomes 0 and the valve opening pressure returns to the original height, and the ABS control pressure increasing mode In this case, the supply pressure exceeds the valve opening pressure and the pressure increasing solenoid valve may be closed. In the aspect of this section, even when the necessary liquid amount becomes zero, the current supplied to the pressure increasing solenoid valve at the present time can be maintained so that the pressure increasing solenoid valve does not close. That is, according to the aspect of this section, it is possible to prevent a delay in the supply of the hydraulic fluid after the supply of the hydraulic fluid is interrupted during the pressure increase mode of the ABS control.

(18) The ABS supply current changing unit is
The current supplied to the pressure increasing solenoid valve is changed so that the valve opening pressure of the pressure increasing solenoid valve becomes higher as the target supply pressure determined by the target supply pressure determining unit is lower. The vehicle hydraulic brake system according to any one of (17).

  The lower the target supply pressure, the greater the differential pressure between the high pressure source and the supply pressure. Therefore, the fluctuation of the supply pressure accompanying the opening and closing of the ABS holding valve of the ABS valve device also increases. The aspect described in this section is configured to determine the amount of current to be changed by the pressure increasing solenoid valve based on the target supply pressure determined by the target supply pressure determination unit. Therefore, according to the aspect of this section, it is possible to effectively suppress fluctuations in the supply pressure in accordance with the magnitude of the target supply pressure.

(21) The vehicle hydraulic brake system includes a plurality of brake devices corresponding to the plurality of wheels, each of which is the brake device,
The ABS supply current changing unit is
In the case where the ABS control is terminated in at least one of the ABS controls executed from the state in which the ABS control is executed in two or more of the plurality of brake devices, Any of (1) to (18), wherein the current supplied to the pressure increasing solenoid valve is changed so that the valve opening pressure of the pressure increasing solenoid valve is lower than the valve opening pressure at that time. The vehicle hydraulic brake system according to claim 1.

(22) The ABS supply current changing unit is
When the ABS control is completed in at least one of the ABS controls, the pressure reducing electromagnetic valve is set so that the valve opening pressure of the pressure reducing electromagnetic valve becomes lower than the valve opening pressure at that time. The vehicle hydraulic brake system according to item (21), which is also configured to change a current supplied to the valve.

  When the ABS control is completed in at least one brake device of which the ABS control is being executed, the hydraulic fluid is supplied to the brake device and there is a risk of overshoot. In the aspect described in the above two items, the supply current to the pressure increasing solenoid valve is changed so that at least the valve opening pressure of the pressure increasing solenoid valve is lower than the valve opening pressure increased as described above. The Therefore, according to the above two aspects, when the ABS control is estimated to be terminated or when the ABS control is terminated, the supply amount of the hydraulic fluid is reduced and the overshoot is suppressed. It is possible. In addition, according to the latter aspect, it is possible to further suppress the overshoot by reducing the valve opening pressure of the pressure reducing solenoid valve and actively reducing the supply pressure. Incidentally, it can be estimated by using various known methods whether or not it is in the above-mentioned “under circumstances where ABS control is estimated to end”.

(23) A vehicle equipped with the vehicle hydraulic brake system is
An electromagnetic motor for applying a driving force to the wheel is provided, and the electromagnetic motor is configured to regenerate electric power generated with the rotation of the wheel so that the electromagnetic motor functions as a regenerative brake device.
The hydraulic brake system for the vehicle
The braking force according to the operation of the brake operation member is generated by the cooperative control with the regenerative brake in the normal state, and is generated only by the vehicle hydraulic brake system during the execution of the ABS control. The vehicle hydraulic brake system according to any one of (1) to (22).

  The vehicle hydraulic brake system described in this section is mounted on, for example, a hybrid vehicle or an electric vehicle. In such a vehicle, in general, cooperative control between the regenerative brake and the hydraulic brake is performed, and during normal braking, the regenerative brake is the main component, and the hydraulic brake has a shortage of the regenerative brake. In such a manner, a braking force corresponding to the brake operation is generated. On the other hand, when ABS control is executed, precise braking force control is required, and therefore braking force is generated only by a hydraulic brake. That is, immediately after the ABS control is executed, the target supply pressure rapidly increases, and the difference between the target supply pressure and the brake pressure is large. As described above, only the current component of the feedback control is used. There is a risk that the supply of hydraulic fluid will be delayed. Therefore, the present brake system having the ABS supply current changing unit capable of increasing the brake pressure earlier is particularly effective in the aspect of this section. Further, in a system including a plurality of brake devices, when some of them are not subjected to ABS control, it is desirable to increase the brake pressure of the brake devices earlier. Even in such a case, according to the brake system having the ABS supply current changing unit, it is possible to increase the brake pressure of the brake device for which the ABS control is not executed earlier.

It is a schematic diagram showing a drive system and a braking system of a hybrid vehicle equipped with a vehicle hydraulic brake system that is an embodiment of the claimable invention. It is the schematic of the brake circuit with which the hydraulic brake system for vehicles which is an example of claimable invention is provided. It is a schematic sectional drawing which shows the linear valve for pressure increase and the linear valve for pressure reduction shown in FIG. It is a graph which shows the relationship between a supply pressure and the valve opening current of the linear valve for pressure reduction. It is a graph which shows the relationship between the differential pressure | voltage of a high pressure source liquid pressure and supply pressure, and the valve opening current of the linear valve for pressure increase. It is a graph which shows the relationship between the differential pressure | voltage of target supply pressure and estimated brake pressure, and correction pressure. It is a graph which shows the relationship between the relationship between the supply current to an electromagnetic linear valve, and the flow volume, and is a graph which shows the difference in the relationship between the supply current and flow volume by the differential pressure | voltage of a physical electromagnetic linear valve. It is a graph which shows the relationship between the inclination of the function shown in FIG. 6, and target supply pressure. The figure which shows the change with respect to passage of time of the supply pressure, the brake pressure, the supply current to the pressure-increasing linear valve, and the supply current to the pressure-reducing linear valve when the supply current change control is executed or not executed, respectively. It is. It is a figure which shows the change with respect to time passage of the supply pressure before and before ABS control is performed, and a brake pressure. It is a graph which shows the relationship between target supply pressure and the valve opening pressure fall amount for pressure reduction. It is a graph which shows the relationship between target supply pressure and the valve opening pressure fall amount for pressure increase. ABS control non-execution wheel when the supply current of the two electromagnetic linear valves is changed so that the valve opening pressure becomes low (FIG. 13B) and when the supply current is not changed (FIG. 13A) It is a figure which shows the change with respect to time passage of the brake pressure of the brake device corresponding to. When the valve opening pressure decrease amount for pressure reduction and the valve opening pressure decrease amount γ for pressure increase are changed in accordance with the target supply pressure (FIG. 14C), and when they are set to constant values (FIG. 14A). , (B)) is a diagram showing the change of the brake pressure of the brake device corresponding to the ABS non-execution wheel with time. It is a graph which shows the relationship between the brake pressure and the amount of hydraulic fluid in the wheel cylinder of a brake device, and is a graph which shows the process of calculating | requiring required flow volume. It is a graph which shows the relationship between the total required flow volume and correction | amendment electric current component which four brake devices require. It is a graph which shows the relationship between a supply pressure and a flow volume, and is a graph which shows the process of calculating | requiring a temporary increase pressure based on a total required flow volume. It is a figure which shows the change with respect to time passage of an actual supply pressure, the brake pressure of four brake devices, a total required flow rate, and a correction current component when the supply current to the pressure increasing linear valve 170 is controlled based on the total required flow rate. is there. It is a flowchart showing the supply pressure control program performed by the brake electronic control unit which is a control apparatus which manages control of the hydraulic brake system for vehicles which is an Example of claimable invention. It is a flowchart which shows the target range control subroutine performed in a supply pressure control program. It is a flowchart which shows the differential pressure dependence electric current change subroutine performed in a target range control subroutine. It is a flowchart which shows the required flow volume dependence electric current change subroutine performed in a target range control subroutine. It is a block diagram which shows the function of the control apparatus which manages control of the hydraulic brake system for vehicles which is an Example of claimable invention.

  Hereinafter, representative embodiments of the claimable invention will be described in detail with reference to the drawings. In addition to the following examples, the claimable invention is implemented in various modes including various modifications and improvements based on the knowledge of those skilled in the art, including the mode described in the above [Mode of Invention]. can do.

<Vehicle configuration>
FIG. 1 schematically shows a drive system and a braking system for a hybrid vehicle equipped with the vehicle hydraulic brake system of this embodiment. The vehicle is equipped with an engine 10 and a drive motor 12 that is an electromagnetic motor as a power source, and a generator 14 that generates electric power by the output of the engine 10 is also mounted. The engine 10, drive motor, and generator 14 are connected to each other by a power split mechanism 16. By controlling the power split mechanism 16, the output of the engine 10 is divided into an output for operating the generator 14 and an output for rotating the driving wheel of the four wheels 18. The output from the motor can be transmitted to the drive wheels. That is, the power split mechanism 16 functions as a transmission related to the driving force transmitted to the drive wheels via the speed reducer 20 and the drive shaft 22. It should be noted that some components such as “wheel 18” are used as a general term, but when indicating that they correspond to any of the four wheels, the left front wheel, the right front wheel, the left rear wheel, The subscripts “FL”, “FR”, “RL”, and “RR” are assigned to the right rear wheel, respectively. According to this notation, the driving wheels in the vehicle are the wheel 18RL and the wheel 18RR.

  The drive motor is an AC synchronous motor and is driven by AC power. The vehicle is provided with an inverter 24, and the inverter 24 can convert electric power from direct current to alternating current or from alternating current to direct current. Therefore, by controlling the inverter 24, the AC power output from the generator 14 is converted into DC power for storing in the HV battery 26, or the DC power stored in the HV battery 26 is driven. Can be converted into AC power for driving the motor. The generator 14 has a configuration as an AC synchronous motor, similarly to the drive motor. That is, in the vehicle of the present embodiment, it can be considered that two AC synchronous motors are mounted. One of them is used as a driving motor mainly for outputting driving force, and the other is used as the generator 14. As mentioned above, it is mainly used for generating electricity by the output of the engine 10.

  The drive motor can also generate power (regenerative power generation) using the rotation of the wheels 18RL and 18RR as the vehicle travels. At this time, in the drive motor connected to the wheels 18RL and 18RR, electric power is generated and a resistance force for stopping the rotation of the drive motor is generated. Therefore, the resistance force can be used as a braking force for braking the vehicle. That is, the drive motor is used as a regenerative brake means for braking the vehicle while generating electric power. Therefore, the vehicle is braked when the regenerative brake is controlled together with the engine brake and a hydraulic brake described later.

  In the present vehicle, the above-described brake control and various other vehicle-related controls are performed by a plurality of electronic control units (ECUs). Of the plurality of ECUs, the main ECU 40 has a function of supervising these controls. For example, the hybrid vehicle can travel by driving the engine 10 and the driving motor, and the driving of the engine 10 and the driving motor are comprehensively controlled by the main ECU 40. . Specifically, the distribution of the output of the engine 10 and the output of the drive motor is determined by the main ECU 40, and the engine ECU 42 that controls the engine 10 and the motor ECU 44 that controls the drive motor and the generator 14 based on the distribution. A command for each control is output to. The main ECU 40 is also connected to a battery ECU 46 that controls the HV battery 26.

  Further, a brake ECU 48 that controls the brake is also connected to the main ECU 40. The vehicle is provided with a brake operation member that is operated by a driver, and the brake ECU 48 determines a target braking force based on an operation amount of the brake operation member, and this target braking force is applied to the main ECU 40. Is output. The main ECU 40 outputs this target braking force to the motor ECU 44, and the motor ECU 44 controls the regenerative braking based on the target braking force, and the execution value thereof, that is, the generated regenerative braking force is supplied to the main ECU 40. Output to. In the main ECU 40, the regenerative braking force is subtracted from the target braking force, and the target hydraulic braking force to be generated in the hydraulic brake system 100 mounted on the vehicle is determined by the subtracted value. The main ECU 40 outputs the target hydraulic braking force to the brake ECU 48, and the brake ECU 48 performs control so that the hydraulic braking force generated by the hydraulic brake system 100 becomes the target hydraulic braking force in a normal state.

<Configuration of vehicle hydraulic brake system>
FIG. 2 conceptually shows a hydraulic brake system 100 provided in the vehicle. The hydraulic brake system 100 includes a brake pedal 110 as a brake operation member, a master cylinder device 112, and a brake actuator 114. The master cylinder device 112 includes a master cylinder 116 that pressurizes hydraulic fluid (brake fluid) based on depression of the brake pedal 110. The master cylinder 116 includes two pressurizing chambers 118 and 120, and the pressurizing chamber 118 is connected to one end of the main liquid passage 122, and the pressurizing chamber 120 is connected to one end of the main liquid passage 122. The other end of the main fluid passage 122 is connected to a wheel cylinder 128FL of a brake device 126FL that brakes the rotation of the left front wheel 18FL, and the other end of the main fluid passage 124 is a wheel of the brake device 126FR that brakes the rotation of the right front wheel 18FR. It is connected to the cylinder 128FR.

  A master cut valve 130 is provided in the middle of the main liquid passage 122, and a master cut valve 132 is provided in the middle of the main liquid passage 124. Each of the master cut valves 130 and 132 is a normally-open electromagnetic on-off valve that permits the flow of hydraulic fluid from the master cylinder 116 to the wheel cylinder 128 in the open state and from the master cylinder 116 to the wheel cylinder 128 in the closed state. The flow of hydraulic fluid toward the In addition, the master cylinder device 112 is provided with a reservoir 134 that stores hydraulic fluid at atmospheric pressure, and hydraulic fluid is supplied from the reservoir 134 to each of the pressurizing chambers 118 and 120 of the master cylinder 116. A stroke simulator 138 is connected to the main fluid passage 122 via a simulator control valve 136 which is a normally closed electromagnetic on-off valve.

  The brake actuator 114 adjusts the hydraulic pressures of the wheel cylinders 128FL and FR, the wheel cylinder 128RL of the brake device 126RL that brakes the rotation of the left rear wheel 18RL, and the wheel cylinder 128RR of the brake device 126RR that brakes the rotation of the right rear wheel 18RR. The power-type hydraulic pressure source device 140 (which may be simply referred to as “hydraulic pressure source device 140”) and an ABS valve device 142 as a hydraulic pressure adjusting device are provided.

  The power hydraulic pressure source device 140 includes a high pressure source device 148 that generates a high hydraulic pressure. The high pressure source device 148 is provided in a high pressure passage 150 having one end connected to the reservoir 134. The high-pressure source device 148 stores the pump 152 that pumps hydraulic fluid from the reservoir 134 through the high-pressure passage 150, the pump motor 154 that drives the pump 152, and the hydraulic fluid discharged from the pump 152 in a pressurized state. It has an accumulator 156 and a relief valve 158 that regulates the discharge pressure of the pump 152 to a set value or less. The other end of the high-pressure passage 150 is connected to the common passage 160, and the high-pressure hydraulic fluid generated by the high-pressure source device 148 can flow through the common passage 160. Further, one end of the low-pressure passage 162 is connected to the common passage 160, and the other end of the low-pressure passage 162 is connected to the reservoir 134. For this reason, the hydraulic fluid in the common passage 160 can flow to the reservoir 134 via the low-pressure passage 162.

  The hydraulic pressure source device 140 includes a normally closed electromagnetic linear valve (hereinafter sometimes referred to as a “pressure increasing linear valve”) 170 provided downstream of the high pressure source device 148 in the high pressure passage 150, and a low pressure passage 162. And a normally closed electromagnetic linear valve (hereinafter also referred to as a “pressure-reducing linear valve”) 172. The pressure-increasing linear valve 170 can control the inflow of the high-pressure hydraulic fluid generated by the high-pressure source device 148 into the common passage 160, while the pressure-decreasing linear valve 172 is in the common passage 160. It is possible to control the outflow of the hydraulic fluid to the reservoir 134. The pressure-increasing linear valve 170 and the pressure-reducing linear valve 172 have a predetermined fixed relationship between the hydraulic pressure difference between the high-pressure side hydraulic fluid and the low-pressure side hydraulic fluid and the supply current, and increase or decrease of the supply current. The valve opening pressure can be changed accordingly. Therefore, the pressure-increasing linear valve 170 and the pressure-decreasing linear valve 172 can continuously change the supply pressure that is the fluid pressure supplied to the common passage 160 by the fluid pressure source device 140 by controlling the supply current. It is possible to easily control the pressure to an arbitrary height.

  More specifically, as shown in FIG. 3, each of the pressure increasing linear valve 170 and the pressure reducing linear valve 172 includes a seating valve including a valve body 180 and a valve seat 182, a spring 184, a solenoid 186, It has. The biasing force F1 of the spring 184 acts in a direction that causes the valve body 180 to approach the valve seat 182, and a current is supplied to the solenoid 186 so that the driving force F2 acts in a direction that causes the valve body 180 to separate from the valve seat 182. To do. In addition, in the pressure-increasing linear valve 170, the differential pressure acting force F3 corresponding to the differential pressure between the hydraulic pressure of the hydraulic fluid pressurized by the high pressure source device 148 and the supply pressure separates the valve body 180 from the valve seat 182. In the pressure-reducing linear valve 172, the differential pressure acting force F <b> 3 according to the hydraulic pressure of the hydraulic fluid stored in the reservoir 134, that is, the differential pressure between the atmospheric pressure and the supply pressure, causes the valve body 180 to act. It acts in the direction of separating from the seat 182. Therefore, in both the pressure-increasing linear valve 170 and the pressure-reducing linear valve 172, the pressure difference acting force F3 is controlled by controlling the amount of current supplied to the solenoid 186, and the pressure-increasing linear valve 170 and the pressure-decreasing linear valve. The valve opening pressure of 172 can be controlled. In other words, the supply pressure can be changed in a controllable manner by causing the pressure-increasing linear valve 170 and the pressure-decreasing linear valve 172 to function as a differential pressure valve.

  Further, the supply pressure can be controlled by causing the pressure increasing linear valve 170 and the pressure reducing linear valve 172 to function as a flow rate adjusting valve. When the difference between the target supply pressure that is the target of the supply pressure and the actual supply pressure that is the actual supply pressure is large, the amount of current supplied to the solenoid 186 is increased, and the flow rate of the hydraulic fluid from the high pressure side to the low pressure side On the other hand, the smaller the difference between the target supply pressure and the actual supply pressure, the less the amount of power supplied to the solenoid 186, thereby changing the actual supply pressure to the target supply pressure. That is, it is possible to supply a current corresponding to the difference between the target supply pressure and the actual supply pressure to the solenoid 186 and change the actual supply pressure to the target supply pressure.

  A high-pressure source hydraulic pressure sensor 190 for detecting the hydraulic pressure of the high-pressure hydraulic fluid generated by the high-pressure source device 148 is provided between the pump 152 of the high-pressure passage 150 and the pressure-increasing linear valve 170. The passage 160 is provided with a common passage hydraulic pressure sensor 192 as a detector for detecting the hydraulic pressure of the working fluid in the common passage 160 as the liquid passage, that is, the supply pressure.

  The four wheel cylinders 128 are connected to the common passage 160 via an ABS valve device 142. The ABS valve device 142 includes an ABS holding valve 200 for increasing and holding the hydraulic pressure of the wheel cylinder 128 and an ABS pressure reducing valve 202 for reducing the hydraulic pressure of the wheel cylinder 128 corresponding to each wheel. Have. The ABS holding valve 200 is provided in the middle of the individual passage 204 connected to the wheel cylinder 128 and the common passage 160, and is an electromagnetic on-off valve. The ABS holding valve 200FL corresponding to the left front wheel 18FL is a normally open valve, and the other three ABS holding valves 200FR, RL, RR are normally closed valves. The ABS pressure reducing valve 202 is provided in the middle of the individual low-pressure passage 206 connected to the downstream side of the ABS holding valve 200 of the individual passage 204 and the low-pressure passage 162, and is an electromagnetic on-off valve. The two ABS pressure reducing valves 202FL and FR corresponding to the front wheels 18FL and FR are normally closed valves, and the two ABS pressure reducing valves 202RL and RR corresponding to the rear wheels 18RL and RR are normally open valves.

  In the present system 10, a brake ECU 48 is provided as shown in FIG. The brake ECU 48 is a control device that controls the operation of the various solenoid valves 130, 132, 136, 170, 172, 200, 202 and the pump 152, and the hydraulic pressure of the hydraulic fluid that acts on the wheel cylinder 128 of each brake device 126. Is to control. The brake ECU 48 includes a controller 210 composed mainly of a computer having a CPU, ROM, RAM, etc., a drive circuit 212 corresponding to a pump motor 154 that drives a pump 152, and various electromagnetic valves 130, 132, 136, 170. , 172, 200, and 202, a plurality of drive circuits 214, 216, 218, 220, 222, 224, and 226 (see FIG. 23). An auxiliary battery 228 is connected to the plurality of drive circuits 212 and the like, and power is supplied from the battery 228 to the pump motor 154 and various control valves 130 and the like.

  Further, a controller 210 is connected to the plurality of drive circuits 212 and the like, and the controller 210 transmits each control signal to the plurality of drive circuits 212 and the like. Specifically, the controller 210 transmits a motor drive signal to the drive circuit 212 of the pump motor 154, and opens and closes various solenoid valves to the drive circuits 214, 216, and 218 of the master cut valves 130 and 132 and the simulator control valve 136, respectively. A control signal for transmitting is transmitted. Furthermore, a current control signal for controlling the magnetic force generated by the solenoid 186 of each linear valve 170, 172 is transmitted to the drive circuits 220, 222 of the pressure increasing linear valve 170 and the pressure reducing linear valve 172, and the ABS. Current control signals for controlling the opening / closing times of various solenoid valves are transmitted to the drive circuits 224 and 226 of the holding valve 200 and the ABS pressure reducing valve 202. In this way, the controller 210 controls the operation of the pump motor 154, the various electromagnetic valves 130, and the like by transmitting the control signals to the drive circuits 212 and the like. In addition to the high pressure source hydraulic pressure sensor 190 and the common passage hydraulic pressure sensor 192, the controller 210 is provided for the stroke sensor 232 for detecting the operation amount of the brake pedal 110, and the rotational speed of each wheel. The wheel speed sensor 234 and the like for detecting the vehicle are connected, and the detection values by the sensors and switches are used in the control of the brake system 100 described later.

<Control of hydraulic brake system for vehicle>
With the above-described structure, in the brake system 100, when the brake pedal 110 is operated by the driver, the hydraulic fluid in the pressurizing chambers 118 and 120 of the master cylinder 116 is caused by the operating force applied to the brake pedal 100. The braking force can be generated by operating the wheel cylinder 128 of the brake device 126 based on the pressurized hydraulic fluid. However, in the present system 10, the wheel cylinder 128 of the brake device 126 is relied on in accordance with the hydraulic fluid regulated by the hydraulic pressure source device 140 without relying on the hydraulic fluid pressurized by the master cylinder 116 at normal times. Electronic braking control to be activated is executed.

  In the electronic braking control, the master cut valves 130 and 132 are excited and closed so that the hydraulic fluid pressurized by the master cylinder 116 does not act on the wheel cylinder 128. The ABS holding valve 200FL corresponding to the left front wheel 18FL is demagnetized in order to operate the wheel cylinder 128 depending on the hydraulic fluid regulated by the hydraulic pressure source device 140, and the other three ABS holding valves. By turning 200FR, RL, and RR into an excited state, all the ABS holding valves 200 are opened. In addition, the two ABS pressure reducing valves 202FL and FR corresponding to the front wheels 18FL and FR are demagnetized, and the two ABS pressure reducing valves 202RL and RR corresponding to the rear wheels 18RL and RR are set in an excited state. The ABS pressure reducing valve 202 is closed. By controlling the various electromagnetic valves in this way, the wheel cylinder 128 is operated by the hydraulic fluid supplied from the hydraulic pressure source device 140. That is, the supply pressure that is the hydraulic pressure of the hydraulic fluid supplied by the hydraulic pressure source device 140 becomes the brake pressure (wheel cylinder pressure) that is the hydraulic pressure of the hydraulic fluid supplied to the wheel cylinder 128.

i) Control of ABS valve device In this brake system 100, control for stabilizing the behavior of the vehicle by controlling the operation of the ABS valve device 142, so-called ABS (Anti-lock Brake System) control, VSC ( Vehicle Stability Control) and TRC (Traction Control) control are executed. The ABS control is a control for suppressing the lock of the wheel at the time of sudden braking or the like, and the VSC control is a control for suppressing a side slip of the wheel at the time of turning of the vehicle. Further, the TRC control is a control for suppressing idling of the drive wheels when the vehicle starts, sudden acceleration, or the like. When the ABS control, VSC control, and TRC control are executed and the ABS control valve device 142 is operated, the control is switched from the cooperative control of the regenerative brake and the hydraulic brake to the control of only the hydraulic brake.

  In the ABS control, VSC control, and TRC control, the ABS holding valve 200 and the ABS pressure reducing valve 202 provided corresponding to each brake device 126 are controlled, so that the brake pressure of each brake device 126 is individually controlled. The Since the ABS control or the like is a known control, only the ABS control related to the claimable invention will be briefly described, and the description of the VSC control and the TRC control will be omitted. The ABS control is executed by the controller 210 of the brake ECU 48 based on the wheel speed, the wheel deceleration, the wheel slip ratio, and the like obtained from the rotation speed of each wheel 18 detected by the wheel speed sensor 234 during braking. Whether or not is determined. When there is a brake device 126 that is determined to require execution of ABS control, the ABS corresponding to the brake device 126 is repeatedly operated so that the brake pressure of the brake device 126 is repeatedly reduced, held, and increased. The holding valve 200 and the ABS pressure reducing valve 202 are controlled. Specifically, in the ABS control, the ABS holding valve 200 is closed and the ABS pressure reducing valve 202 is opened to prohibit the supply of hydraulic fluid from the hydraulic pressure source device 140 to the brake device 126 and the reservoir 134. Both the ABS holding valve 200 and the ABS pressure reducing valve 202 are closed and the hydraulic pressure is supplied from the hydraulic pressure source device 140 to the brake device 126. And the holding mode in which the flow of hydraulic fluid to the reservoir 134 is prohibited to hold the brake pressure, the ABS holding valve 200 is opened, the ABS pressure reducing valve 202 is closed, and the brake is supplied from the hydraulic pressure source device 140 to the brake. The pressure increasing mode in which the hydraulic fluid is allowed to be supplied to the device 126 and the brake pressure is increased can be switched based on the wheel deceleration, the slip ratio, or the like. It has become. As a result, the wheel 18 is prevented from being locked and a stable braking force is generated.

The ABS holding valve 200 and the ABS pressure reducing valve 202 are controlled in order to precisely control the increase of the brake pressure particularly in the pressure increasing mode. The ratio is changed by changing the ratio (duty ratio). The duty ratio is calculated based on a target brake pressure, an actual brake pressure, or the like. Incidentally, in the present system 100, the actual brake pressure P _WC is estimated based on the operating state of the ABS valve device 142. The estimation method of the brake pressure P _WC is a known method and will be briefly described. First, the duty ratios of the ABS holding valve 200 and the ABS pressure reducing valve 202 after the ABS control is executed, and the ABSs are described. Based on the valve opening times of the holding valve 200 and the ABS pressure reducing valve 202, the amount of change in the brake pressure _PWC is calculated. Then, the actual supply pressure Pr just before the ABS control is performed, based on the change amount of the calculated brake pressure P _WC, braking pressure P _WC is estimated. Further, the target brake pressure in the pressure increasing mode is determined such that the brake pressure increases with the target pressure increasing gradient. When determining the target pressure increase gradient, the actual supply pressure Pr detected by the common passage hydraulic pressure sensor 192 is used.

ii) Supply pressure control by hydraulic pressure source device A) Normal control (target supply pressure control)
The target hydraulic pressure braking force to be generated by the brake device 126 in the electronic braking control is calculated by the main ECU 40 as described above, and the supply pressure capable of generating the target hydraulic pressure braking force is set as the target supply pressure P ^* . Calculation is performed by the controller 210 of the brake ECU 48. In the normal time when the ABS device 140 is not operated, the calculated target supply pressure P ^* is compared with the actual supply pressure Pr detected by the common passage hydraulic pressure sensor 192, and the actual supply pressure Pr ^* is compared. When the pressure Pr is higher than the target supply pressure P ^* by a set difference ΔP or more, the hydraulic pressure source device 140 is controlled to reduce the actual supply pressure Pr, and the actual supply pressure Pr is lower than the target supply pressure P ^* by a set difference ΔP or more. In this case, the hydraulic pressure source device 140 is controlled to increase the actual supply pressure Pr.

More specifically, when the actual supply pressure Pr becomes equal to or higher than the pressure reduction threshold P ₊ ^* obtained by adding the set difference ΔP to the target supply pressure P ^* , the pressure increase linear valve 170 is closed to close the pressure increase linear valve 170. Is demagnetized. That is, the energization amount to the solenoid 186 of the pressure increasing linear valve 170 is set to zero. Then, the energization amount to the solenoid 186 of the pressure reducing linear valve 172 is controlled so that the actual supply pressure Pr decreases to the target supply pressure P ^* . In the present system 100, the amount of current applied to the solenoid 186 of the pressure reducing linear valve 172, that is, The target supply current i _SLR is a feedback current component i _FB according to the difference between the valve opening current component i _dw of the pressure reducing linear valve 172 determined according to the actual supply pressure Pr and the target supply pressure P ^* and the actual supply pressure Pr. Based on _{_SLR} , determined according to the following formula.
i _SLR = i _dw −i _FB _ _SLR
More specifically, the valve opening current component i _dw is the difference between the actual supply pressure Pr acting on the valve body 180 of the pressure-reducing linear valve 172 and the hydraulic pressure of the hydraulic fluid stored in the reservoir 134, that is, the actual supply pressure. The current is determined according to Pr. The valve opening current component i _dw of the pressure reducing linear valve 172 has a certain relationship with the supply pressure Pk, and is determined according to the following equation.
i _dw = f (Pk) = I _dw −K _dw · Pk
Here, f (Pk) is a function that depends on the supply pressure Pk, and as shown in FIG. 4, it is a function that linearly decreases as the supply pressure Pk increases. The feedback current component is determined using a feedback control method based on the difference between the target supply pressure P ^* and the actual supply pressure Pr, and is determined according to the following equation.
i _FB _ _SLR = K _SLR・ (P ^* -Pr) (K _SLR : decompression gain)
Therefore, the target supply current i _SLR of the pressure reducing linear valve 172 is expressed by the following equation.
i _SLR = I _dw −K _dw · P ^* −K _SLR · (P ^* −Pr)

On the other hand, when the actual supply pressure Pr becomes equal to or less than the pressure increase threshold value P ₋ ^* obtained by subtracting the set difference ΔP from the target supply pressure P ^* , the pressure reducing linear valve 172 is closed to close the pressure reducing linear valve 172. The energization amount to the solenoid 186 is set to zero. Then, the energization amount to the solenoid 186 of the pressure-increasing linear valve 170 is controlled so that the actual supply pressure Pr increases to the target supply pressure P ^* . The target supply current i _SLA to the solenoid 186 of the pressure-increasing linear valve 170 includes the valve opening current component i _up of the pressure-increasing linear valve 172 determined according to the actual supply pressure Pr, the target supply pressure P ^*, and the actual supply pressure Pr. Based on the feedback current component i _{FB — SLA} corresponding to the difference of
i _SLA = i _up + i _FB _ _SLA
More specifically, the valve opening current component i _up is a current determined according to the differential pressure (Ph−Pr) between the high pressure source hydraulic pressure Ph detected by the high pressure source hydraulic pressure sensor 190 and the actual supply pressure Pr. The valve-opening current component i _up of the pressure-increasing linear valve 170 has a certain relationship with the differential pressure (Ph−Pk) between the high-pressure source hydraulic pressure Ph and the supply pressure Pk, and is determined according to the following equation.
i _up = g (Ph−Pk) = I _up −K _up · (Ph−Pk)
Here, g (Ph−Pk) is a function depending on the differential pressure (Ph−Pk) between the high pressure source hydraulic pressure Ph and the supply pressure Pk, and as shown in FIG. 5, the differential pressure (Ph−Pk) ) Increases linearly as the function increases. The feedback current component is determined using a feedback control method based on the difference between the target supply pressure P ^* and the actual supply pressure Pr, and is determined according to the following equation.
_{i FB _ SLA = K SLA ·} (P * -Pr) (K SLA: pressure increase gain)
Therefore, the target supply current i _SLA of the pressure increasing linear valve 170 is expressed by the following equation.
i _SLA = I _up −K _up · (Ph−P ^* ) + K _SLR · (P ^* −Pr)

When the actual supply pressure Pr and the target supply pressure P ^* are substantially equal, that is, when the difference between the target supply pressure P ^* and the actual supply pressure Pr is smaller than ΔP, the actual supply pressure Pr is maintained to be maintained. The energizing amount to the solenoid 186 of the pressure-increasing linear valve 170 and the energizing amount to the solenoid 186 of the depressurizing linear valve 172 are each 0. In this way, by controlling the supply current to the solenoid 186 of the pressure-increasing linear valve 170 or each solenoid 186 of the pressure-decreasing linear valve 172 in the normal state, the supply pressure becomes the target supply pressure, and each brake device 126 Is set as a target hydraulic braking force.

B) Control during ABS device operation (target range control)
However, if the ABS valve device 142 is operated by the ABS control or the like while the control of the supply pressure at the normal time (hereinafter sometimes referred to as “target supply pressure control”) is being executed as described above, each ABS is retained. Since the valve 200 and each ABS pressure reducing valve 202 are frequently switched between open and closed states, the volume in the fluid passage such as the common passage 160 into which the hydraulic fluid supplied by the fluid pressure source device 140 flows frequently changes, and the supply pressure Suddenly fluctuate. That is, the energized state of the pressure-increasing linear valve 170 and the pressure-reducing linear valve 172 is frequently switched due to fluctuations in the supply pressure, and it may be difficult to follow the target supply pressure.

Therefore, in the brake system 100, when the ABS valve device 142 is operated, the actual supply pressure Pr and the target supply pressure P ^* are approximately equal, that is, the target supply pressure P ^* and the actual supply pressure Pr. Even when the difference is smaller than ΔP, the target range control for controlling the hydraulic pressure source device 140 is executed so that the supply pressure falls within the target range. Specifically, a current that is large enough to open the pressure-reducing linear valve 172 when the supply pressure becomes equal to or higher than the pressure-reducing threshold P ₊ ^* (= P ^* + ΔP) is supplied to the pressure-reducing linear valve 172. Subsequently, when the supply pressure becomes equal to or lower than the pressure increase threshold value P ₋ ^* (= P ^* −ΔP), a current that is large enough to open the pressure increase linear valve 170 is continuously supplied to the pressure increase linear valve 170. As a result, the supply pressure is maintained within the target range. In other words, a current that causes the pressure reducing threshold value P ₋ ^* to be the valve opening pressure of the pressure reducing linear valve 172 is continuously supplied to the pressure reducing linear valve 172, and the pressure increasing threshold value P ₊ ^* is the valve opening of the pressure increasing linear valve 170. By continuing to supply the pressure increasing current to the pressure-increasing linear valve 170, the pressure-increasing linear valve 170 and the pressure-decreasing linear valve 172 function as differential pressure valves, and the supply pressure is maintained within the target range. ing.

As described above, the target supply current i _SLR to the solenoid 186 of the pressure reducing linear valve 172 is determined so that the pressure reducing linear valve 172 is opened at a pressure corresponding to the pressure reducing threshold value P ₊ ^* . Specifically, it is determined according to the function shown in FIG. 4 showing the relationship between the valve opening current i _dw of the pressure reducing linear valve 172 and the supply pressure Pk. That is, the target supply current i _SLR is a valve opening current corresponding to the pressure reduction threshold value P ₊ ^* , and is determined according to the following equation.
i _SLR = f (P ₊ ^* ) = I _dw −K _dw · P ₊ ^*

On the other hand, the target supply current i _SLA to the solenoid 186 of the pressure-increasing linear valve 170 is determined so that the pressure-increasing linear valve 170 is opened at a pressure corresponding to the pressure-increasing threshold value P ₋ ^* . Specifically, it is determined according to the function shown in FIG. 5 showing the relationship between the differential pressure (Ph−Pk) between the high pressure source hydraulic pressure Ph and the supply pressure Pk and the valve opening current i _up of the pressure increasing linear valve 170. . That is, the target supply current i _SLA is a valve opening current corresponding to the differential pressure (Ph−P ₋ ^* ) between the high pressure source hydraulic pressure Ph and the pressure increase threshold value P ₋ ^*, and is determined according to the following equation.
i _SLA = g (Ph−P ₋ ^* ) = I _up −K _up · (Ph−P ₋ ^* )

  When the ABS valve device 142 is operated, the supply pressure is controlled to the target range by controlling the supply current to each solenoid 186 of the pressure-increasing linear valve 170 and the pressure-decreasing linear valve 172 as described above. It is controlled to fit inside. For this reason, in the situation where the ABS holding valve 200 and the ABS pressure reducing valve 202 are frequently opened and closed by the operation of the ABS valve device 142, the pressure increasing linear valve 170 and the pressure increasing pressure valve do not follow the target supply pressure. It is possible to suppress frequent switching of the energization state of the pressure-reducing linear valve 172.

Note that the supply pressure may deviate from the target range due to a sudden change in the target supply pressure P ^*, a sudden change in the brake pressure, or the like. In such a case, it is desirable to quickly bring the supply pressure within the target range. The feedback current component described above is added. In other words, when the supply pressure is equal to or greater than the pressure reduction threshold P ₊ ^* , the target supply current i _SLR to the pressure reducing linear valve 172 is a feedback current corresponding to the difference between the target supply pressure P ^* and the actual supply pressure Pr. The component i _{FB — SLR} is reduced. When the supply pressure is equal to or lower than the pressure increase threshold value P ₋ ^* , the target supply current i _SLA to the pressure increasing linear valve 170 is fed back according to the difference between the target supply pressure P ^* and the actual supply pressure Pr. The current component i _{FB — SLA} is added.
i _SLR = f (P ₊ ^* ) − K _SLR · (P ^* −Pr)
i _SLA = g (Ph−P ₋ ^* ) + K _SLA · (P ^* −Pr)

C) Supply current change at the time of ABS control execution a) Outline of supply current change control As described above, when ABS control is executed, brake pressure is repeatedly increased, reduced and maintained by the operation of the ABS valve device. Is called. That is, the ABS valve device repeatedly switches between a state where the hydraulic fluid supply from the hydraulic pressure source device 140 is allowed to be supplied to the brake device 126 and a state where the hydraulic fluid is shut off, thereby changing the supply pressure. There is a problem of end. Further, when the brake pressure is increased, the state in which the supply of hydraulic fluid from the hydraulic pressure source device 140 to the brake device 126 is allowed to be blocked and the state in which the brake fluid is blocked are controlled at shorter time intervals in order to control the pressure increase gradient. It can be switched repeatedly. As a result, the supply pressure fluctuates in a vibration manner, and there is a problem that the supply pressure is not stable. As described above, since the supply pressure detected by the common passage hydraulic pressure sensor 192 is used for determining the brake pressure increase gradient, if the supply pressure is not stable, the brake pressure is increased appropriately. There is a possibility that it cannot be pressed.

In order to cope with the above problem, in the present system 100, when the ABS valve device 142 is operated by executing the ABS control, the supply to the pressure-increasing linear valve 170 determined by the target range control described above is performed. The electric current is changed so that the valve opening pressure of the pressure increasing linear valve 170 becomes higher. Further, the supply current to the pressure-reducing linear valve 172 determined by the target range control is also changed so that the valve opening pressure of the pressure-reducing linear valve 172 becomes higher. Specifically, in order to increase the valve opening pressure of the pressure-increasing linear valve 170, a correction current is added to the supply current i _SLA to the pressure-increasing linear valve 170 to increase the target supply current, or in target range control A correction pressure is added to the target supply pressure P ^* to set a target supply pressure higher. Note that if the correction pressure is added to the target supply pressure P ^* in the target range control and the target supply pressure is set higher, the valve opening pressure of the pressure-reducing linear valve 172 can be increased at the same time. Incidentally, the valve opening pressure of the pressure-reducing linear valve 172 can be increased by reducing a certain amount of current from the supply current i _SLR to the pressure-reducing linear valve 172 to reduce the target supply current. Hereinafter, the change of the supply current to the linear valves 200 and 202 will be described in more detail.

b) Control during execution of four-wheel ABS control First, when the ABS control is executed in the brake devices 126 corresponding to all four wheels 18, the correction pressure α _{p is} ^added to the target supply pressure P ^* in the target range control. by changing the corrected target supply pressure _P ^* + α _p plus, set a higher supply pressure as a target, so as to increase the valve opening pressure and the valve-opening pressure of the pressure-reducing linear valve 172 of the pressure-increasing linear valve 170 Has been. That is, the corrected target supply current i ′ _SLA to the pressure increasing linear valve 170 and the corrected target supply current i ′ _SLR to the pressure reducing linear valve 172 are determined according to the following equations.
i ′ _SLA = I _up −K _up · {Ph− (P ₋ ^* + α _p )}
i ′ _SLR = I _dw −K _dw · (P ₊ ^* + α _p )
Further, the correction pressure α _p corresponds to each of the four brake devices 126 estimated based on the target supply pressure P ^* determined as described above according to the brake operation and the operating state of the ABS valve device 142. To be determined based on the estimated brake pressure _PWC . First, before the determination of the correction pressure alpha _p, the estimated brake pressure P _WC of each of the four brake devices 126, the reference brake pressure P _WCS used to determine the correction pressure alpha _p is calculated. Specifically, the reference brake pressure P _WCS is determined based on the oil amount rigidity (the amount of fluid required for the pressure) of the wheel cylinder 128 of the brake device 126 corresponding to the front wheels 18FL and FR, and the brake corresponding to the rear wheels 18RL and RR. Weighting is performed with respect to the oil amount rigidity of the wheel cylinder 128 of the device 126, and calculation is performed according to the following equation.
P _WCS = {K _F · (P _{WC — FL} + P _{WC — FR} ) + K _R · (P _{WC — RL} + P _{WC — RR} )} / 4
The reference brake pressure may be, for example, an average value, a maximum value, a minimum value, or the like of the estimated brake pressure _PWC corresponding to each of the four brake devices 126.

Then, the magnitude of the correction pressure α _p is determined according to the function shown in FIG. 6 according to the difference between the calculated reference brake pressure P _WCS and the target supply pressure P ^* . That is, the correction pressure α _p is determined so as to increase as the difference between the reference brake pressure P _WCS and the target supply pressure P ^* increases. The correction pressure α _p is determined to have a magnitude corresponding to the magnitude of the target supply pressure P ^* . FIG. 7 shows the relationship between the supply current and the flow rate of the linear valves 200 and 202, and shows the difference in the relationship between the supply current and the flow rate due to the differential pressure. It shows the change in flow rate when the current is increased from certain valve opening currents I ₁ , I ₂ , and I ₃ . The valve opening current is smaller in the order of I ₁ , I ₂ , and I ₃ . In other words, the differential pressure increases in that order. As can be seen from FIG. 7, the smaller the valve opening current (the greater the differential pressure), the smaller the increase in flow rate relative to the increase in current. That is, in the pressure-increasing linear valve 170, the lower the valve opening pressure (≈target supply pressure P ^* ), the smaller the increase in flow rate with respect to the increase in current. Therefore, in the present system 100, in consideration thereof, the correction pressure α _p is determined so as to increase as the target supply pressure P ^* decreases. Specifically, in the present system 100, by changing in accordance with the inclination S of functions shown in FIG. 6 to the target supply pressure, as the target supply pressure P ^* is low, corrected pressure alpha _p is increased. FIG. 8 shows the relationship between the target supply pressure P ^* and the slope S. In other words, the slope as the target supply pressure P ^* is less S is large, as the target supply pressure P ^* is lower correction pressure alpha _p is increased. Also, the higher the target supply pressure P ^* is lower correction target supply pressure P ^* + alpha _p is large, the current supplied to the pressure-increasing linear valve 170 is large, and the flow rate of the hydraulic fluid is adapted to increase.

Also, when executing the ABS control, as in the target range control described above, if the supply pressure is out of the target range, specifically, if the supply pressure is below the target range, the supply pressure is quickly Therefore, a feedback current component is added so as to be within the target range. That is, when the supply pressure is equal to or lower than the lower limit value (P ₋ ^* + α _P −ΔP) of the target range corresponding to the corrected target supply pressure P ^* + α _P , the target supply current i to the pressure increasing linear valve 170 is reached. 'A feedback current component corresponding to the difference between the corrected target supply pressure P ^* + α _P and the actual supply pressure Pr is added to _SLA .
i ′ _SLA = I _up −K _up · {Ph− (P ₋ ^* + α _p )} + K _SLA · (P ^* + α _P −Pr)
On the other hand, if the supply pressure is exceeded the corrected target supply pressure _P ^* + α P, in order to prevent the boost excessive, the supply current change control described above is prohibited. That is, the target value of the supply pressure is returned from the corrected target supply pressure P ^* + α _P to the target supply pressure P ^* corresponding to the brake operation, and the target range control described above is executed.

  The case where the above-described supply current change control is being executed is compared with the case where it is not being executed, with reference to FIGS. 9 and 10. FIG. 9 shows changes of the supply pressure and the brake pressure with respect to time when the supply current change control is executed and when it is not executed. FIG. 9A shows a case where the operation is not executed. In this case, it can be seen that the supply pressure fluctuates in a vibrational manner. In addition, because the pressure increase gradient of the brake pressure is determined using the supply pressure that fluctuates in vibration, when the brake pressure is switched from the holding mode to the pressure increase mode, the pressure increases rapidly. It can be seen that the pressure cannot be increased with an appropriate pressure increase gradient. On the other hand, as shown in FIG. 9B, in this system, the target supply pressure is increased by the supply current change control, so that the differential pressure of the pressure-increasing linear valve 170 is reduced and the supply pressure is increased. The gradient when the pressure is increased is reduced, and the number of times the pressure reducing linear valve 172 is opened is also reduced. That is, the present system 100 can stabilize the supply pressure. In addition, since the system 100 controls the brake pressure using such a stable supply pressure, the brake pressure can be appropriately reduced, held, and increased in the ABS control.

FIG. 10 shows changes in supply pressure and brake pressure over time before and after ABS control is executed. As shown also in this figure, in the present system 100, when ABS control is executed, a value higher than the target supply pressure P ^* corresponding to the brake operation is set as the supply pressure target, and the actual supply pressure is set to supply current change control. Is maintained at a high value compared to when not running. As a result, the system 100 can efficiently and appropriately increase the brake pressure in the pressure increasing mode in the ABS control.

c) Control when ABS control ends in at least one brake device Next, when ABS control is executed in the four brake devices 126 and the above-described supply current change control is executed, at least one of the brakes is executed. Consider a case where the ABS control is completed in the device 126. In such a case, since the supply pressure is increased, there is a possibility that the hydraulic fluid is supplied to the brake device 126 for which the ABS control has been completed and overshoots. Therefore, in the present system 100, when it is estimated that the ABS control is completed in at least one brake device 126, the supply current of the pressure reducing linear valve 172 is changed so that the valve opening pressure of the pressure reducing linear valve 172 becomes lower. In addition, the supply current of the pressure-increasing linear valve 170 is also changed so that the valve opening pressure of the pressure-increasing linear valve 170 is also lowered. Incidentally, whether or not the ABS control is ended has been conventionally performed by various methods, and is assumed to be performed by at least one of the various methods, and detailed description thereof will be omitted here. And

Specifically, when it is estimated that the ABS control is completed in at least one brake device 126, the valve opening pressure when the pressure reducing linear valve 172 performs the target range control described above is opened. Is determined to be lower than the pressure. That is, the pressure reducing linear valve 172 has a pressure reducing linear pressure so that the valve opening pressure becomes a pressure P ₊ ^* −β obtained by subtracting the pressure reducing opening pressure reduction amount β from the valve opening pressure P ₊ ^* at the time of target range control. The target supply current i ′ _SLR to the valve 172 is determined according to the following equation.
i ′ _SLR = I _dw −K _dw · (P ₊ ^* −β)
Note that the valve opening pressure decrease amount β for pressure reduction is determined based on the target supply pressure P ^* . When the target supply pressure P ^* is high, in the pressure-reducing linear valve 172, the differential pressure between the upstream side and the downstream side is large. As can be seen from the characteristics shown in FIG. The increase in flow rate is small relative to the increase in. That is, in the pressure-reducing linear valve 172, the higher the valve opening pressure (≈target supply pressure P ^* ), the smaller the increase in flow rate with respect to the increase in current. Therefore, in the present system 100, in consideration of this, the higher the target supply pressure P ^{*, the} larger the depressurization valve opening pressure decrease amount β is determined to increase the flow rate to the reservoir 134. Incidentally, FIG. 11 shows the relationship between the target supply pressure P ^* and the valve opening pressure decrease amount β for pressure reduction.

On the other hand, the valve opening pressure decrease amount γ is determined so that the valve opening pressure of the pressure increasing linear valve 170 is lower than the valve opening pressure when the target range control described above is performed. That is, the pressure increasing linear valve 170 is set so that the valve opening pressure becomes the pressure P ₋ ^* −γ obtained by subtracting the valve opening pressure decrease amount γ from the valve opening pressure P ₋ ^* at the time of target range control. The target supply current i ′ _SLA to the valve 170 is determined according to the following equation.
i ′ _SLA = I _up −K _up · {Ph− (P ₋ ^* −γ)}
The valve opening pressure decrease amount γ for increasing pressure is also determined based on the target supply pressure P ^* .
The pressure-increasing linear valve 170 is determined such that the higher the valve opening pressure (≈target supply pressure P ^* ), the larger the valve opening pressure decrease amount γ increases so as to reduce the amount of hydraulic fluid supplied. Incidentally, FIG. 12 shows the relationship between the target supply pressure P ^* and the valve opening pressure decrease amount γ for increasing pressure.

  With reference to FIGS. 13 and 14, the effect of the control in the case where it is estimated that the ABS control is terminated in the at least one brake device 126 described above will be described. FIG. 13 shows a case where the supply current of the linear valves 170 and 172 is changed so that the valve opening pressure becomes low (FIG. 13B) and a case where it is not changed (FIG. 13A). The change with respect to time of the brake pressure of the brake device 126 corresponding to an ABS control non-execution wheel is shown. As can be seen from FIG. 13B, the brake pressure overshoot corresponding to the ABS non-execution wheel is suppressed.

FIG. 14 is a diagram comparing the valve opening pressure decrease amount β for pressure reduction and the valve opening pressure decrease amount γ for pressure increase, which are changed according to the target supply pressure P ^* , with a case where they are constant values. 14 (a) and 14 (b) show the case where the valve opening pressure decrease amount β for pressure reduction and the valve opening pressure decrease amount γ for pressure increase are made constant, and FIG. 14 (b) shows the case of FIG. 14 (a). This is when the target supply pressure is higher. FIG. 14A shows the case where the brake pressure corresponding to the ABS control non-execution wheel can suppress overshoot, while FIG. 14B shows the case where the target supply pressure is relatively high. The brake pressure corresponding to the execution wheel has overshot. That is, although the supply current of the linear valves 170 and 172 was changed so that the valve opening pressure was lowered, it is considered that the amount of change was insufficient. On the other hand, in the present system 100 in which the valve opening pressure decrease amount β for pressure reduction and the valve opening pressure decrease amount γ for pressure increase are changed according to the target supply pressure P ^* , the target supply pressure is relatively high. However, the brake pressure corresponding to the ABS non-execution wheel can suppress the overshoot.

d) Control in the case where there are non-executed wheels for ABS control Next, among the four brake devices 126, if there are those for which ABS control is not executed, that is, one to three for which ABS control is executed. The control when there is one will be described. When there is an ABS control non-execution wheel, the correction current component α _i is added to the target supply current i _SLA of the pressure-increasing linear valve 170 determined in the above-described target range control, thereby increasing the pressure-increasing linear valve 170. The valve opening pressure is increased. That is, basically, the supply current i ′ _SLA to the pressure increasing linear valve 170 is determined according to the following equation.
i ′ _SLA = I _up −K _up · (Ph−P ₋ ^* ) + α _i

The correction current component α _i is determined based on the total flow rate Q _ABS required for each of the four brake devices 126. More specifically, in each of the four brake devices 126, the estimated brake pressure P _WC described above and the operation status of the corresponding ABS holding valve 200 (specifically, in the open / close state of the ABS holding valve 200 or in the pressure increasing mode). In some cases, the required flow rate Q (the required flow rate of the hydraulic fluid) is estimated based on the target brake pressure calculated from the target pressure increase gradient or the like. In addition, the relationship between the brake pressure in the wheel cylinder 128 of each brake device 126 and the amount of hydraulic fluid is shown in FIG. Then, the estimated required flow rate is summed, and the total required flow rate Q _ABS is calculated. Then, according to the relationship between the flow rate and the current in the pressure-increasing linear valve 170 shown in FIG. 16, a current for realizing the total required flow rate Q _ABS is obtained, and the current is used as the correction current component α _i .

Further, when it is assumed that the hydraulic fluid corresponding to the total necessary flow rate Q _ABS has flowed into the common passage 160 from the state where the supply pressure is the target supply pressure P ^* , the provisional increase pressure p of the supply pressure in that case Is calculated. Specifically, the temporary increase pressure p is calculated according to the relationship between the supply pressure and the amount of hydraulic fluid in consideration of the wheel cylinders 128 of the four brake devices 126 shown in FIG. Then, a temporary target supply pressure P ^* + p plus the temporary over boost p to the target supply pressure P ^*, comparing the actual supply pressure Pr, the actual supply pressure Pr is less than the temporary target supply pressure P ^* + p In this case, the supply current is changed. In other words, when the actual supply pressure Pr exceeds the temporary target supply pressure P ^* + p, the supply current change control is prohibited and the target range control described above is executed. In this case as well, as in the target range control described above, when the target pressure is below the target range, a feedback current component is added to quickly bring the supply pressure within the target range. ing. From the above, when there is an ABS control non-execution wheel, the supply current i ′ _SLA to the pressure increasing linear valve 170 is determined according to the following equation.
i ′ _SLA = g (Ph−P ₋ ^* ) (P ^* + p <Pr)
i ′ _SLA = g (Ph−P ₋ ^* ) + α _i (P ₋ ^* <Pr ≦ P ^* + p)
i ′ _SLA = g (Ph−P ₋ ^* ) + α _i + K _SLA · (P ^* −Pr) (Pr ≦ P ₋ ^* )

For example, in the present system 100, since the ABS holding valve 200 is controlled at a relatively short time interval, the ABS holding valve 200 is closed to achieve the target pressure increasing gradient even in the pressure increasing mode. In some cases, all of the four ABS holding valves 200 are closed. As described above, since the correction current component α _i is determined based on the total required flow rate Q _ABS, when all the four ABS holding valves 200 are closed, the total required flow rate Q _ABS becomes 0, and the correction current component α _{i is} also 0. That is, there is a possibility that the increased valve opening pressure of the pressure-increasing linear valve 170 is lowered and the pressure-increasing linear valve 170 is closed. For example, when there is a pressure increasing mode among the four brake devices 126, if the pressure increasing linear valve 170 is closed, there is a delay in the supply of the hydraulic fluid immediately thereafter. Therefore, in the present system 100, when the four ABS holding valves 200 are closed, the correction current component α _i immediately before that is held.

FIG. 18 shows the actual supply pressure Pr, the brake pressure P _WC of the four brake devices 126, the total required flow rate Q _ABS , and the correction current component α when the supply current to the pressure increasing linear valve 170 is controlled as described above. _The change of _i over time is shown. As described above, since the supply current to the pressure-increasing linear valve 170 is increased so as to realize the flow rate of the hydraulic fluid required at the present time, as can be seen from this figure, for example, the pressure-increasing mode is set in the ABS control. When it is started, the required flow rate is large and the correction current component α _i is also large. Further, the lower the brake pressure, the larger the flow rate required for pressure increase (see FIG. 9). In this case, the correction current component α _i is larger. Further, the above control prevents excessive supply of hydraulic fluid to the brake device 126 corresponding to the ABS control non-execution wheel. Further, overshoot of the supply pressure can be suppressed, and the supply pressure can be converged to the target supply pressure P ^* .

<Control program>
In the system 100, the control of the supply pressure, which is the hydraulic pressure of the hydraulic fluid generated by the hydraulic pressure source device 140, is set while the ignition switch is turned on by the supply pressure control program shown in the flowchart in FIG. This is performed by being repeatedly executed by the controller 210 of the brake ECU 48 at a predetermined time interval Δt. Below, the flow of the control processing by the supply pressure control program will be described with reference to the flowchart shown in the figure.

In the processing by the supply pressure control program, first, in step 1 (hereinafter simply referred to as “S1”, the same applies to other steps), the target supply is performed based on the target hydraulic braking force calculated in the main ECU 40. The pressure P ^* is determined. The controller 210 stores map data related to the target supply pressure P ^* using the target hydraulic pressure braking force as a parameter, and the target supply hydraulic pressure P ^* is determined by referring to the map data. In S2, the actual supply pressure Pr is detected by the common passage hydraulic pressure sensor 192, and in S3, the high pressure source hydraulic pressure Ph is detected by the high pressure source hydraulic pressure sensor 190.

Next, in S4, it is determined whether or not the ABS valve device 142 is operating. That is, when ABS control, VSC control, and TRC control are being executed, it is determined that the ABS valve device 142 is operating. When the ABS valve device 142 is not operating, the target supply pressure control at S6 and below is executed. Specifically, first, in S6, it is determined whether or not the actual supply pressure Pr is greater than the pressure reduction threshold P ₊ ^* (= P ^* + ΔP). If it is determined that the actual supply pressure Pr is greater than the pressure reduction threshold P ₊ ^* , the target supply current i _SLA of the pressure increasing linear valve 170 is determined to be 0 in S7, and the target supply current i of the pressure reducing linear valve 172 is determined. _{The SLR} is determined according to the above-described equation that is the sum of the valve opening current component and the feedback current component. Next, in S8, it is determined whether or not the actual supply pressure Pr is lower than the pressure increase threshold value P ₋ ^* (= P ^* −ΔP). If it is determined that the actual supply pressure Pr is lower than the pressure increase threshold value P ₋ ^* (= P ^* −ΔP), in S9, the target supply current i _SLR of the pressure reducing linear valve 172 is determined to be 0, and the pressure increase The target supply current i _SLA of the linear valve 170 is determined according to the above-described equation obtained by adding the valve opening current component and the feedback current component. In S8, when it is determined that the actual supply pressure Pr is equal to or higher than the pressure increase threshold value P ₋ ^* (= P ^* −ΔP), that is, the actual supply pressure Pr and the target supply pressure P ^* substantially coincide with each other. If so, the target supply current i _SLA of the pressure-increasing linear valve 170 and the target supply current i _SLR of the pressure- _decreasing linear valve 172 are determined to be 0 in S10.

If it is determined in S4 that the ABS valve device 142 is operating, target range control is executed in S5. The target range control is performed by executing a target range control subroutine whose flowchart is shown in FIG. In the processing by the target range control subroutine shown in the flowchart of FIG. 20, first, in S21, it is determined whether or not ABS control is being executed. When the ABS control is not executed, normal target range control is executed after S22. That is, a valve opening current component having a pressure increase threshold P ₋ ^* as the valve opening pressure is always added to the target supply current i _SLA of the pressure increasing linear valve 170, and the target supply current i of the pressure reducing linear valve 172 is set. A valve opening current component having a magnitude that uses the pressure reduction threshold P ₊ ^* as the valve opening pressure is always added to the _SLR . If it is determined in S22 that the actual supply pressure Pr is higher than the pressure reduction threshold P ₊ ^* , in S25, the target supply current i _SLR of the pressure reducing linear valve 172 is the valve opening current component and the feedback current component. To be determined. If it is determined in S23 that the actual supply pressure Pr is lower than the pressure increase threshold value P ₋ ^* , in S26, the target supply current i _SLA of the pressure increasing linear valve 170 is the valve opening current component and the feedback current. It is determined by adding the ingredients.

If it is determined in S21 that ABS control is being performed, supply current change control during ABS control is performed in S27 and thereafter. In S27, it is determined whether or not ABS control is being executed in the brake devices 126 corresponding to all four wheels 18. When the ABS control is determined to be running in all four brake devices 126, in S28, based on the difference between the target supply pressure P ^* and the estimated brake pressure P _WC, changes the target supply current Processing is performed. On the other hand, when it is determined that the ABS control is not executed in all four brake devices 126, that is, when the ABS control is executed for one or three wheels, the brake device is determined in S29. Based on the amount of hydraulic fluid required by 126, a process for changing the target supply current is performed.

Processing for changing the target supply current based on the difference between the target supply pressure P ^* and the estimated brake pressure P _WC in S28 is performed by the differential pressure relying current changing sub-routine indicated by a flow chart of FIG. 21 is executed . In the process based on the differential pressure-dependent current changing subroutine, first, in S31, it is determined whether or not there is any of the four brake devices 126 that is estimated to end the ABS control. When the ABS control is determined that there is no brake device 126 to exit, at S32 following, based on the difference between the target supply pressure P ^* and the estimated brake pressure P _WC, 2 two open linear valves 170 and 172 Processing for changing the supply current is performed so that the pressure is increased. Specifically, in S32, the acquired estimated brake pressure P _WC four brake devices 126, in S33, the reference brake pressure P _WCS is calculated according to the equation described above on the basis of them. Then, in S34, based on the target supply pressure P ^* and the difference between the target supply pressure P ^* and the reference brake pressure P _WCS , the map data set as shown in FIGS. 6 and 8 is referred to. The correction pressure α _p is determined.

Then, in S35, a value obtained by adding the target supply pressure P ^* and the corrected pressure alpha _p is the actual supply pressure Pr is compared. If the actual supply pressure Pr is lower than the value obtained by adding the target supply pressure P ^* and the corrected pressure alpha _p, in S36, the target for controlling the two linear valves 170, 172, above the target supply pressure from P ^*, it is changed to the corrected target supply pressure P ^* + alpha _p obtained by adding the target supply pressure P ^* and the corrected pressure alpha _p. In S37 to S41, processing similar to that in S22 to S26 of the target range control subroutine described above is performed, and target supply currents i _SLA and i _{SLR of the} two linear valves 170 and 172 are determined. If the actual supply pressure Pr is higher than the sum of the target supply pressure P ^* and the correction pressure α _p , the processing of S37 to S41 is performed at the target supply pressure P ^* to prohibit the change of the supply current. Is done.

Further, in S31, when it is determined that any of the four brake devices 126 is estimated to end the ABS control, the valve opening pressures of the two linear valves 170 and 172 become lower in S42 and the subsequent steps. As described above, a process for changing the supply current is performed. In S42, referring to the map data set as shown in FIGS. 11 and 12, the pressure reducing valve opening pressure decrease amount β and the pressure increasing valve opening pressure decrease amount γ corresponding to the target supply pressure P ^* are determined. Is done. In step S43, the two linear valves 170 and 172 are set so that the opening pressures of the two linear valves 170 and 172 take into consideration the valve opening pressure decrease amount β for reducing pressure and the valve opening pressure decrease amount γ for increasing pressure. Target supply currents i _SLA and i _SLR are determined. As described above, after the target supply currents i _SLA and i _{SLR of the} two linear valves 170 and 172 are determined, one process of the differential pressure-dependent current changing subroutine is completed.

On the other hand, the processing for changing the target supply current based on the amount of hydraulic fluid required by the brake device 126 in S29 of the target range control subroutine is executed by the necessary fluid amount-based current change subroutine shown in the flowchart of FIG. Is done by doing. In the processing by the necessary fluid amount-dependent current change subroutine, first, in S51, it is necessary until the next program execution of each of the four brake devices 126 while referring to the map data set as shown in FIG. The amount of required hydraulic fluid (necessary flow rate Q) is estimated. Next, in S52, the required flow rates Q of the four brake devices 126 are totaled to calculate the total required flow rate Q _ABS , that is, the flow rate to be realized by the pressure increasing linear valve 170. In S53, the correction current component α _i is determined while referring to the map data set as shown in FIG. At the same time, referring to the map data set as shown in FIG. 17, the upper pressure is increased when the hydraulic fluid of the total required flow rate Q _ABS flows into the common passage 160 from the state at the target supply pressure P ^*. p is estimated.

Next, in S54 and thereafter, target supply currents i _SLA and i _{SLR of the} two linear valves 170 and 172 are determined. Briefly, but treatment with the required fluid amount-dependent current changes subroutine, when the value obtained by adding the Kariue boosting p to the target supply pressure P ^* (temporary target supply pressure P ^* + p) than the actual supply pressure pr is low The correction current component α _i is added to the target supply current i _SLA of the pressure-increasing linear valve 170 determined by the processing of S22 to S26 of the target range control subroutine. As described above, after the target supply currents i _SLA and i _{SLR of the} two linear valves 170 and 172 are determined, one process of the necessary flow rate-dependent current changing subroutine is completed.

In S11 of the supply pressure control program, a control signal based on the target supply current i _SLA of the pressure increasing linear valve 170 is transmitted to the drive circuit 220, and the control based on the determined target supply current i _SLR of the pressure reducing linear valve 172 is determined. After the signal is transmitted to the drive circuit 222, one execution of the program ends.

<Functional configuration of control device>
The brake ECU 48 that performs the above-described control and functions as a control device can be considered to have various functional units that perform the various processes described above. Specifically, as shown in FIG. 23, the brake ECU 48 executes the supply pressure control program S1 to determine the target supply pressure P ^* that is the hydraulic pressure of the hydraulic fluid supplied by the hydraulic pressure source device 140. A target supply pressure determining unit 250, a supply pressure control unit 252 that executes S2 and subsequent steps of the supply pressure control program, and controls the supply current to the pressure increasing linear valve 170 and the pressure reducing linear valve 172 based on the target supply pressure; have. In addition, the brake ECU 48 estimates the brake pressure of each brake device 126 when the ABS control execution unit 254 that executes the ABS control control and the ABS valve device 142 such as the ABS control are operating. And a brake pressure estimating unit 256.

  Furthermore, the brake ECU 48 executes the target range control subroutine S27 to S28, and when the ABS control is executed, the valve opening pressures of the two linear valves 170 and 172 are higher than when the ABS control is not executed. As shown, it has an ABS control supply current changing unit 260 that changes the supply current to them. The ABS control-time supply current changing unit 260 adds a correction pressure to the target supply pressure determined by the target supply pressure determining unit 250 to determine a corrected target supply pressure, and a target supply current. A correction target supply current determining unit 264 that determines a correction current component to be added. The corrected target supply pressure determining unit 262 includes a portion for executing the processes of S32 to S34 and S36 of the differential pressure-dependent current changing subroutine, and the corrected target supply current determining unit 264 is a necessary dependent current changing subroutine. The part which performs the process of S51-S53 of is comprised.

    12: Drive motor (electromagnetic motor) 18: Wheel 48: Brake ECU (control device) 100: Hydraulic brake system 110: Brake pedal (brake operation member) 126: Brake device 128: Wheel cylinder 134: Reservoir 140: Power type Liquid pressure source device (hydraulic pressure source device) 142: ABS valve device 148: High pressure source device 160: Common passage 170: Pressure increasing linear valve (pressure increasing solenoid valve) 172: Pressure reducing linear valve (pressure reducing solenoid valve) 192: Common passage hydraulic pressure sensor (hydraulic pressure detector) 200: ABS holding valve 202: ABS pressure reducing valve 210: Controller 234: Wheel speed sensor 250: Target supply pressure determination unit 252: Supply pressure control unit 254: ABS control control execution unit 256 : Brake pressure estimator 260: ABS system When the supply current changing section 262: correction target pressure determining section 264: correction target supply current determining unit

P _WC : Estimated brake pressure P ^* : Target supply pressure Pr: Actual supply pressure P ₊ ^* : Pressure reduction threshold i _SLR : Target supply current (linear valve for pressure reduction) i _dw : Valve opening current component (linear valve for pressure reduction) i _FB _ _SLR: feedback current component (pressure-reducing linear valve) Pk: supply pressure P _- ^*: increasing pressure threshold i _SLA: target supply current (pressure-increasing linear valve) i _{Stay up-:} opening current component (pressure-increasing linear valve) i _FB _ _SLA : Feedback current component (linear valve for pressure increase) α _p : Correction pressure P ^* + α _p : Correction target supply pressure P _WCS : Reference brake pressure β: Decrease in valve opening pressure for pressure reduction γ: Decrease in valve opening pressure for pressure increase α _i : Correction current component Q _ABS : Total required flow rate

Claims (13)

A brake operating member operated by a driver;
A brake device that is provided corresponding to the wheel and operates by the hydraulic pressure of the hydraulic fluid supplied to the wheel to apply a braking force to the wheel;
It is a device that supplies hydraulic fluid with regulated hydraulic pressure to the brake device, and (a) a high pressure source that generates a high hydraulic pressure, and (b) the valve opening pressure is changed according to the current supplied to itself. A solenoid valve for increasing the pressure of the hydraulic fluid to be supplied; and (c) a solenoid valve for reducing the pressure of the hydraulic fluid to be supplied by changing the valve opening pressure according to the current supplied to itself. A hydraulic pressure source device,
An ABS valve device which is provided between the hydraulic pressure source device and the brake device and is operated when performing ABS control for coping with locking of the wheel;
(A) a target supply pressure determination unit that determines a target supply pressure that is a target of a supply pressure that is a hydraulic pressure of hydraulic fluid supplied by the hydraulic pressure source device based on an operation of the brake operation member; ) Based on the target supply pressure, a supply pressure control unit that controls a supply current to the pressure increasing solenoid valve and the pressure reducing solenoid valve of the hydraulic pressure source device; and (C) to execute the ABS control An ABS control execution unit for controlling the ABS valve device; and (D) when the ABS control is executed by the ABS control execution unit, the opening of the pressure-increasing solenoid valve is compared with a case where the ABS control is not executed. A vehicle hydraulic brake system comprising: a control device having an ABS supply current changing unit that changes a current supplied to the pressure increasing solenoid valve so that the valve pressure increases. The ABS supply current changing unit is
2. The current supplied to the pressure increasing solenoid valve is changed based on a difference between the target supply pressure determined by the target supply pressure determination unit and a brake pressure that is a hydraulic pressure of the brake device. Hydraulic brake system for vehicles. The ABS supply current changing unit is
A current supplied to the pressure-increasing solenoid valve is increased so that a valve opening pressure of the pressure-increasing solenoid valve becomes higher as a difference between the target supply pressure determined by the target supply pressure determining unit and the brake pressure is larger. The hydraulic brake system for a vehicle according to claim 2 to be changed. The ABS supply current changing unit is
4. The method according to claim 1, wherein a required fluid amount that is a fluid amount to be supplied to the brake device is estimated, and a current supplied to the pressure increasing solenoid valve is changed based on the required fluid amount. The vehicle hydraulic brake system according to claim 1. The ABS supply current changing unit is
The hydraulic brake system for a vehicle according to claim 4, wherein a current supplied to the pressure increasing solenoid valve is changed so that the valve opening pressure of the pressure increasing solenoid valve becomes higher as the amount of the required fluid increases. The vehicle hydraulic brake system includes a plurality of brake devices corresponding to the plurality of wheels, each of which is the brake device,
The ABS supply current changing unit is
5. The current supplied to the pressure-increasing solenoid valve is changed based on the estimated amount of fluid required for each of the plurality of brake devices and based on the total amount of fluid required for each of the plurality of brake devices. Item 6. The hydraulic brake system for a vehicle according to Item 5. The ABS supply current changing unit is
When the ABS valve device cuts off the supply of hydraulic fluid to all of the plurality of brake devices, the valve opening pressure of the pressure-increasing solenoid valve increased by itself and determined by the target supply pressure determining unit The vehicle hydraulic brake system according to claim 6, wherein a pressure difference with respect to the valve opening pressure of the pressure increasing solenoid valve determined with respect to the target supply pressure is prohibited from decreasing. The ABS supply current changing unit is
The current supplied to the pressure increasing solenoid valve is changed so that the valve opening pressure of the pressure increasing solenoid valve becomes higher as the target supply pressure determined by the target supply pressure determining unit is lower. Item 8. The hydraulic brake system for a vehicle according to any one of Items 7. The ABS supply current changing unit is
When the ABS control is being executed, the target supply pressure determined by the target supply pressure determination unit is corrected to be higher than the target supply pressure, and the supply pressure control unit corrects the target supply pressure. The current supplied to the pressure-increasing solenoid valve is changed by allowing the supply current to the pressure-increasing solenoid valve and the pressure-reducing solenoid valve to be controlled based on Item 9. The hydraulic brake system for a vehicle according to any one of Items 8. The ABS supply current changing unit is
The vehicle hydraulic brake system according to claim 9, wherein when the supply pressure exceeds the target supply pressure corrected by itself, a change in current supplied to the pressure increasing solenoid valve is prohibited. The ABS supply current changing unit is
When the ABS control is executed, the current supplied to the pressure reducing solenoid valve is also changed so that the valve opening pressure of the pressure reducing solenoid valve becomes higher than when the ABS control is not executed. The vehicle hydraulic brake system according to any one of claims 1 to 10, which is configured as follows. The vehicle hydraulic brake system includes a plurality of brake devices corresponding to the plurality of wheels, each of which is the brake device,
The ABS supply current changing unit is
In the case where the ABS control is terminated in at least one of the ABS controls executed from the state in which the ABS control is executed in two or more of the plurality of brake devices, The current supplied to the pressure-increasing solenoid valve is changed so that the valve-opening pressure of the pressure-increasing solenoid valve is lower than the valve-opening pressure at that time. Hydraulic brake system for vehicles as described in one. The ABS supply current changing unit is
When the ABS control is completed in at least one of the ABS controls, the pressure reducing electromagnetic valve is set so that the valve opening pressure of the pressure reducing electromagnetic valve becomes lower than the valve opening pressure at that time. The hydraulic brake system for a vehicle according to claim 12, wherein the current supplied to the valve is also changed.

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