JP2022001765A - Slip control device of torque converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately perform slip control of a torque converter when a transient fluctuation of an engine torque is caused by depressing or releasing an accelerator pedal. SOLUTION: A calculation means 51 for calculating a target slip rotation speed of a lockup clutch 20 based on a vehicle operating state, a feed forward control amount based on the target slip rotation speed, and a target slip rotation speed and an actual slip rotation speed. The calculation means 53A that calculates the slip torque capacity of the lockup clutch 20 from the feedback control amount based on the above, the calculation means 59 that corrects the torque signal of the engine 1 by the gain and calculates the estimated engine torque, and the estimated engine torque. A calculation means 58 for calculating the engagement command pressure of the torque converter 20 from the slip torque capacity is provided, and when the time change rate of the torque signal becomes the first predetermined value or more by the accelerator operation of the vehicle, the gain is increased by a predetermined amount. The gain changing means 60 is provided. [Selection diagram] Fig. 1

Description

The present invention relates to a slip control device for a torque converter installed in a vehicle.

A slip control device has been developed that controls the engagement capacity of the lockup clutch so that the actual slip rotation between the input / output elements of the torque converter that transmits the rotation from the prime mover (engine) converges to the target slip rotation.

For example, in Patent Document 1, the target slip rotation of the torque converter is obtained from the operating state of the vehicle, the slip rotation command value that matches the actual slip rotation with the target slip rotation is calculated, and the planned motor total performance data is obtained from the operating state of the vehicle. The prime mover output torque is estimated based on the map, and the lockup clutch engagement pressure command value corresponding to the slip rotation command value is calculated from the prime mover output torque estimated value and the slip rotation command value. A technique for controlling the fastening pressure is disclosed.

Further, in Patent Document 1, the slip rotation gain is obtained from the turbine rotation of the torque converter, the target converter torque is obtained by dividing the slip rotation command value by the slip rotation gain, and the target converter torque is subtracted from the prime mover output torque estimated value. It is also disclosed that the target lockup clutch engagement capacity is obtained and the lockup clutch is controlled by this.

Japanese Unexamined Patent Publication No. 2000-97333

By the way, in a vehicle equipped with a torque converter slip control device, when the accelerator pedal is depressed, the lockup capacity becomes too small and the engine speed rises excessively, or when the accelerator pedal is depressed again. In the process of developing the device by the present inventors, it was found that the lockup capacity becomes excessive and the vehicle causes a forward / backward acceleration shock.

The present invention was devised focusing on such a problem, and by appropriately performing slip control when the engine torque is transiently fluctuated due to depressing or depressing the accelerator pedal, excessive engine rotation is generated. It is an object of the present invention to provide a slip control device for a torque converter capable of suppressing the occurrence of a shock in a vehicle or a vehicle.

In order to achieve the above object, the torque converter slip control device of the present invention is equipped in a vehicle, and the slip state of the torque converter having a lockup clutch interposed between the engine and the stepped automatic transmission is obtained. A control device for controlling, the target slip rotation calculation means for calculating the target slip rotation speed of the lockup clutch based on the operating state of the vehicle, the feed forward control amount based on the target slip rotation speed, and the said. The slip torque capacity calculation means for calculating the slip torque capacity of the lockup clutch from the feedback control amount based on the target slip rotation speed and the actual slip rotation speed, and the torque signal of the engine are corrected by the gain to obtain the estimated engine torque. It is provided with an estimated engine torque calculating means for calculating, and an engaging command pressure calculating means for calculating the engaging command pressure of the lockup clutch from the estimated engine torque and the slip torque capacity, and the torque is calculated by operating the accelerator of the vehicle. It is characterized in that it is provided with a gain changing means for increasing the gain by a predetermined amount when the time change rate of the signal becomes equal to or higher than the first predetermined value.

It is preferable that the gain changing means stops the increase of the gain when the rate of change of the torque signal becomes less than the second predetermined value smaller than the first predetermined value during the increase of the gain.
It is preferable that the gain changing means stops the gain increasing process after a predetermined time has elapsed after increasing the gain.
The predetermined amount is preferably a preset constant value.
It is preferable that the predetermined amount is set to a larger value as the time change rate of the accelerator operation amount is larger.
It is preferable to provide a gain change prohibiting means for prohibiting an increase in the gain during the shift of the stepped automatic transmission.

According to the present invention, when the torque signal of the engine suddenly changes with the operation of the accelerator pedal, the gain for calculating the estimated engine torque from this torque signal is increased, so that the estimated engine at the time of transient fluctuation of the engine torque It is possible to suppress the influence of the delay of the torque on the actual engine torque and optimize the engagement command pressure of the lockup clutch. As a result, it is possible to suppress the occurrence of excessive engine rotation when the accelerator pedal is depressed and the occurrence of forward / backward acceleration shock of the vehicle when the accelerator pedal is released.

It is a system diagram which shows the main part of the drive system and the control system of the vehicle to which the slip control device of the torque converter which concerns on one Embodiment of this invention is applied. It is a block diagram of the main part of the slip control device of the torque converter which concerns on one Embodiment of this invention. It is a time chart explaining the control by the slip control device of the torque converter which concerns on one Embodiment of this invention, (a) shows the case where this control is not applied, (b) shows the case where this control is applied. .. It is a flowchart explaining the control by the slip control device of the torque converter which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the embodiments shown below are merely examples, and there is no intention of excluding the application of various modifications and techniques not specified in the following embodiments. Each configuration of the following embodiments can be variously modified and implemented without departing from the purpose thereof, and can be selected as necessary or combined as appropriate.

[1. Overall system configuration]
FIG. 1 is a system diagram showing a main part of a vehicle drive system and a control system to which a torque converter slip control device according to the present embodiment is applied.
As shown in FIG. 1, the drive system of the vehicle includes an engine (internal combustion engine) 1 as a drive source, a torque converter 2, a speed change mechanism 3, and a power transmission system 7 downstream in the power transmission direction of the speed change mechanism 3. It is equipped with a drive wheel (not shown) downstream of the power transmission direction.

The automatic transmission 10 is configured by housing the torque converter 2 and the transmission mechanism 3 in the transmission case 10A. Further, in FIG. 1, a portion upstream of the torque converter 2 in the power transmission direction (mainly the engine 1) and a portion between the torque converter 2 and the friction engaging element 31 described later (a turbine described later in the torque converter 2). Each inertial mass of the runner (including the runner 24) and the portion downstream of the friction engaging element 31 in the power transmission direction is shown by simple blocks A, B, and C.

The torque converter 2 is a starting element having a torque increasing function, and includes a pump impeller 23 connected to the engine output shaft 11 via a converter housing 22, a turbine runner 24 connected to the torque converter output shaft 21, and a case. The component is a stator 25 provided via a one-way clutch (not shown). In the present embodiment, the lockup clutch 20 is provided so that the engine output shaft 11 (= torque converter input shaft) and the torque converter output shaft 21 can be directly connected when the torque increasing function is not required.

A stepped speed change mechanism that achieves a plurality of forward speeds and reverse speeds is applied to the speed change mechanism 3. Each shift is achieved by selectively engaging a plurality of frictional engagement elements 31 such as clutches or brakes. For example, when starting forward, the friction engaging element 31 that achieves the first speed is engaged, and when starting backward, the friction engaging element 31 that achieves the reverse stage is engaged. At the time of forward traveling, the friction engaging element 31 that achieves an appropriate shift stage is engaged according to the vehicle speed and the engine load (here, the throttle valve opening degree).

The engagement and disengagement states of the lockup clutch 20 and each friction engagement element 31 are controlled by hydraulic pressure through the corresponding hydraulic control valve (control valve) 41 to engage the lockup clutch 20 and each friction engagement element 31. This is done by adjusting the resultant pressure. The hydraulic control valve 41 is a solenoid valve installed in the hydraulic control unit 4, and is operated by a command signal of the automatic transmission control unit 5 (hereinafter referred to as ATCU).

The hydraulic pressure control valve 41 adjusts the hydraulic pressure of the hydraulic oil supplied from an oil pump (not shown) according to a command signal to adjust the engagement state of the lockup clutch 20 and each friction engagement element 31. The present control device is characterized in that the engaged state of the lockup clutch 20 is adjusted, and in particular, the lockup clutch 20 is slip-controlled. Therefore, the ATCU 5 has a shift control unit (shift control means) 50A, which is a function for controlling engagement and disengagement of each friction engagement element 31 in order to switch shift stages such as upshift and downshift. The lock-up clutch control unit (lock-up clutch control means) 50B, which is a function for controlling the engaged state of the lock-up clutch 20, is provided.

Although not shown, the lockup clutch 20 responds to the differential pressure PA-PR between the torque converter apply pressure PA and the torque converter release pressure PR on both sides (input side and output side), and the release pressure PR is increased. If it is higher than the apply pressure PA, the lockup clutch 20 is released and the torque converter input / output elements are not directly connected. When the release pressure PR is lower than the apply pressure PA, the lockup clutch 20 is engaged and the torque converter is turned on. Reduce or reduce the slip rotation speed between output elements to zero.

The fastening force of the lockup clutch 20, that is, the lockup capacity is determined by the above differential pressure PA-PR, and the larger the differential pressure, the larger the engaging force of the lockup clutch 20 and the higher the lockup capacity. .. The differential pressure PA-PR is controlled by the hydraulic control valve 41. The differential pressure PA-PR is also simply referred to as a lockup pressure.

[2. Lock-up clutch slip control]
Here, the ATCU 5 will be described with a focus on the lockup clutch control unit 50B. The lockup clutch control unit 50B has an engine rotation speed (corresponding to the engine rotation speed) Ne, a turbine rotation speed of the torque converter 2 (corresponding to the turbine rotation speed ωt) Nt, a vehicle speed V, and a throttle opening TVO. Vehicle operating state information such as gear ratio ip, oil temperature (AT fluid temperature) T _ATF , engine torque signal (hereinafter, also simply referred to as torque signal) Te, etc. are input from each sensor.

The lockup clutch control unit 50B calculates a target slip rotation speed Tslp of the lockup clutch 20 in order to control the engaged state of the lockup clutch 20 based on these signals. Target slip rotation calculation unit (target slip rotation). Speed calculation means) 51, actual slip rotation calculation unit (actual slip rotation speed calculation means) 52 that calculates the actual slip rotation speed ωslp, and control so that the actual slip rotation speed ωslp follows the target slip rotation speed Tslp. A slip control unit (slip control means) 53 is provided.

The target slip rotation calculation unit 51 calculates the target slip rotation speed Tslp based on the operating conditions of the vehicle such as vehicle speed V, throttle opening TVO, turbine rotation speed Nt, gear ratio ip, and oil temperature T _ATF. The target slip rotation speed Tslp is the input / output rotation speed difference of the lockup clutch 20, and the rotation speed (turbine rotation speed) ωt of the turbine runner 24 is subtracted from the rotation speed (impeller rotation speed) ωi of the pump impeller 23. The value. Here, a test or the like is performed in advance, and the slip rotation speed at which torque fluctuation and muffled noise are minimized is stored in a map or the like according to the operating condition of the vehicle, and is stored in the map or the like. The target slip rotation speed Tslp is calculated with reference to this map or the like.

The actual slip rotation calculation unit 52 calculates the actual slip rotation speed ωslp by subtracting the turbine rotation speed ωt detected by the sensor from the impeller rotation speed ωi detected by the sensor. Since the impeller rotation speed ωi corresponds to the engine rotation speed Ne, the impeller rotation speed ωi is obtained from the engine rotation speed Ne obtained by the engine rotation sensor 64. The turbine rotation speed ωt is obtained by the turbine rotation sensor 65.

The slip control unit 53 controls so that the actual slip rotation speed ωslp follows the target slip rotation speed Tslp. Here, the slip rotation speed of the lockup clutch 20 is the input torque input to the lockup clutch 20. And the difference (torque difference) ΔT between the output torque output from the lockup clutch 20 (torque capacity transmitted by the lockup clutch 20) and ΔT, the slip control unit 53 responds to the target slip rotation speed. The torque difference ΔT is calculated, and the torque value obtained by subtracting this torque difference ΔT from the input torque to the lockup clutch 20 is used as the torque capacity target value (hereinafter, simply referred to as torque capacity) Tlu transmitted by the lockup clutch 20. , The torque capacity of the lockup clutch 20 is controlled to achieve the target slip rotation speed.

Further, the slip control unit 53 controls the slip state of the lockup clutch 20 by using the feedback control and the feedforward control. Therefore, as shown in FIG. 2, the slip control unit 53 includes a slip torque capacity calculation unit (slip torque capacity calculation means) 53A having a feedback control unit 54 and a feed forward control unit 55, and a command value conversion unit 58. The slip torque capacity calculation unit 53A obtains a torque value (slip torque capacity) according to the target slip rotation speed, and derives a command value for controlling the engagement state of the lockup clutch 20 based on this slip torque capacity. I try to do it.

The slip control unit 53 will be further described.
As shown in FIG. 2, the slip control unit 53 performs processing corresponding to a sudden change in torque, specifically, phase lead compensation, for the target slip rotation speed Tslp output from the target slip rotation calculation unit 51. .. The target slip rotation speed Tslpa subjected to this processing is sent to the feedback control unit 54 and the feedforward control unit 55 of the slip torque capacity calculation unit 53A.

Further, the output (torque level) Tcnvfb from the feedback control unit 54 and the output (torque level) Tcnvff from the feedforward control unit 55 are sent to the addition unit 53b and added, and the slip for achieving the target slip rotation speed is achieved. It is output as the torque capacity Tcnv.
The slip torque capacity Tcnv calculated by the slip torque capacity calculation unit 53A is sent to the subtraction unit 53c, and is based on the engine torque signal Te by the torque signal processing unit 59 as the estimated engine torque calculation unit (estimated engine torque calculation means). This slip torque capacity Tcnv is subtracted from the processed torque value Tea to calculate the torque capacity (control value) Tlu of the lockup clutch 20, and the torque capacity Tlu is sent to the command value conversion unit 58 to lock up the clutch. It is converted into the indicated current value Ilu of the control valve 41 that controls the engagement state of 20 and output.

The feedback control unit 54 processes the target slip rotation speed Tslpa according to the normative model, processes the output target slip rotation speed with respect to the wasted time of the lockup clutch 20, and sets the processed target slip rotation speed Tslp. The difference errslp (= Tslp−ωslp) from the actual slip rotation speed ωslp calculated by the actual slip rotation calculation unit 52 is calculated. Further, in order to suppress this difference errslp, proportional / integral control (PI control) processing is performed, and the slip rotation amount is converted into a feedback slip torque capacity Tcnvfb which is a torque amount and output as a feedback control value.

The feedforward control unit 55 performs a process of compensating for the phase with respect to the target slip rotation speed Tslpa, converts the obtained target slip rotation speed Tslpff into a feedforward slip torque capacity Tcnvff, and outputs it as a feedforward control value.

In the slip torque capacity calculation unit 53A, the feedback slip torque capacity Tcnvfb output from the feedback control unit 54 and the feedforward slip torque capacity Tcnvff output from the feedforward control unit 55 are added by the addition unit 53b. It is output as the slip torque capacity Tcnv.

Further, the torque signal processing unit 59 performs waste time processing (reference numeral 59a), primary delay processing (reference numeral 59b), and gain correction (reference numeral 59c) on the engine torque signal Te, and outputs the torque value Tea.
However, the gain used for gain correction in the torque signal processing unit 59 (hereinafter, also simply referred to as gain) is increased under specific conditions. This will be described later.

The subtraction unit 53c subtracts the slip torque capacity Tcnv from the torque value Tea based on the engine torque signal Te, and calculates the torque capacity Tlu of the lockup clutch 20.
The command value conversion unit 58 performs torque-differential pressure conversion processing on the torque capacity Tlu, performs phase lead compensation, performs command pressure-current conversion processing, and outputs the obtained indicated current value Ilu to the control valve 41. do.

In this way, a current is sent to the solenoid of the control valve 41 according to the indicated current value Ilu output from the slip control unit 53, and the hydraulic pressure (differential pressure) of the lockup clutch 20 is set to the predetermined value Pl by the control valve 41. The slip state of the controlled lockup clutch 20 is controlled to the target state.

In the lockup clutch 20, since the torque capacity is controlled to the value of Tlu during this slip control, the difference Ttc (= Te-Tlu) between the torque value Tea based on the engine torque signal Te and the torque capacity Tlu is the slip torque. It becomes the capacity. The lockup clutch 20 has a slip rotation (rotational speed ωslp) according to the slip torque amount (= Ttc-Idωt / dt) obtained by subtracting the inertial shuttlek change amount Iedωt / dt due to the change in the turbine rotation speed ωt. , Generates with a predetermined response characteristic [ωslp = Gslp / (Tcslp s + 1)].
Further, in this slip control, the capacity of the lockup clutch 20 is gradually reduced even when the torque of the engine 1 does not increase. As a result, it is possible to suppress a decrease in the engine rotation speed Ne, and it is possible to prevent the actual slip rotation speed ωslp from decreasing and the lockup clutch 20 from being engaged.

[3. Gain used for gain correction of torque signal Te]
Since the engine torque signal Te is calculated based on the detection result of the operating state of the engine 1 such as the engine speed Ne, a delay in the calculation timing occurs, and this engine torque signal Te is delayed with respect to the actual engine torque. I know that.

As explained in the column of [Problems to be Solved by the Invention], in this device, when the accelerator pedal is depressed, the lockup capacity becomes too small and the engine rotation rises excessively, and the accelerator is used. This is an attempt to avoid or suppress a forward / backward acceleration shock in the vehicle due to an excessive lockup capacity when the pedal is depressed back.

When the cause of the lockup capacity becoming too small or too large was investigated, it was found that the cause was that the engine torque signal Te used for controlling the lockup clutch 20 was delayed with respect to the actual engine torque.

For example, as shown in FIG. 3A, when the accelerator pedal is depressed while the lockup clutch 20 is slightly slipped and the accelerator pedal is released for cruise driving, the throttle opening is corresponding to the depression. Since the TVO starts up and the fuel is recovered from the fuel cut state, the actual engine torque suddenly increases at the time point t1 and the driving state is set. However, since the engine torque signal Te is delayed with respect to this rapid increase in the actual engine torque, the torque capacity target value Tlu calculated based on the engine torque signal Te also increases with a delay with respect to the rapid increase in the actual engine torque.
As a result, the torque capacity of the lockup clutch 20 becomes insufficient, the engine rotation speed Ne also increases rapidly in response to the rapid increase in the actual engine torque, and the engine rotation rises excessively.

On the other hand, in this device, under the situation where the accelerator pedal is switched from release (off) to depression (on) and a rapid increase in actual engine torque occurs, for example, as shown in FIG. 3 (b), Gain. By temporarily increasing the gain used in the gain correction when calculating the torque value Tea from the engine torque signal Te, the torque value Tea is calculated by strongly reflecting the latest engine torque signal Te that has begun to increase. I have to.

Therefore, the gain changing unit (gain changing means) that increases the gain by a predetermined amount under a predetermined condition, that is, a switching between the accelerator pedal being turned off and on and a sudden increase in the actual engine torque occurs in the ATCU 5. ) 60 is provided. Switching between the accelerator pedal off and on can be detected, for example, as switching between the idle switch on and off.

However, since the actual engine torque is not detected, it is not possible to directly grasp the sudden increase in the actual engine torque. Therefore, the gain changing unit 60 pays attention to the time change rate ΔTe of the engine torque signal Te when the accelerator pedal is switched between off and on, and when the time change rate ΔTe becomes the first predetermined value ΔTe1 or more. It is determined that the actual engine torque is suddenly increased, and the gain is increased.

Note that FIG. 3B shows a broken line and a solid line for Gain, where the broken line is the target value and the solid line is the command value. The command value changes the gain in a ramp shape to prevent sudden changes in the gain and stabilize the control.
Further, the predetermined amount for increasing the gain may be a constant amount by conducting a test in advance, or may be a variable amount such as increasing as the accelerator pedal depression speed (time change rate of the accelerator operation amount) increases. good.

FIG. 3 illustrates a case where the lockup capacity becomes too small and the engine rotation rises excessively due to the accelerator pedal being depressed from the released state. However, the accelerator pedal is released from the depressed state. It was found that the cause is that the engine torque signal Te used to control the lockup clutch 20 is delayed with respect to the actual engine torque even when the lockup capacity becomes excessive and a front-rear acceleration shock occurs in the vehicle. is doing.

That is, when the accelerator pedal is changed from the depressed state to the released state, the actual engine torque suddenly decreases, and the engine torque signal Te suddenly decreases after this. In this case, since the decrease of the engine torque signal Te is delayed, the lockup capacity becomes excessive, and the lockup clutch 20 is in a state of complete engagement or close to this for a minute time, and a front-rear acceleration shock occurs in the vehicle. It is considered to be.

In this case as well, by temporarily increasing the gain, the torque value Tea is calculated by strongly reflecting the latest engine torque signal Te that has begun to decrease, thereby preventing or suppressing the lockup capacity from becoming excessive. can do.

Since such an increase in gain may be performed only in the vicinity of the transient fluctuation of the engine torque, the gain changing unit 60 changes the torque signal Te change rate (absolute value) ΔTe from the first predetermined value ΔTe1 while the gain is increased. When it becomes less than the second predetermined value ΔTe2, which is also small, the increase in gain is stopped.
Alternatively, the gain changing unit 60 may be configured to stop the gain increasing process after a predetermined time set in advance has elapsed after increasing the gain.

However, if the gain is changed during the shift (during the shift change), the shift control may be hindered. Therefore, the gain change prohibition unit (gain change prohibition means) that prohibits the gain change during the shift. 61 is equipped, and the gain change by the gain change unit 60 is regulated.

[4. Action and effect]
Since the vehicle shift control device according to the embodiment of the present invention is configured as described above, for example, as shown in the flowchart of FIG. 4, the time change rate ΔTe of the torque signal is the first when the accelerator operation is switched on and off. When the value becomes 1 predetermined value ΔTe1 or more, the gain can be changed by the gain changing unit 60 that increases the gain by a predetermined amount. In FIG. 4, F is a flag set to 1 during the gain change, and is set to 0 when the gain is not changed, that is, when the gain is a normal value.

First, it is determined whether or not the flag F is 0, and when the flag F is 0, that is, when the gain is a normal value, it is determined whether or not the idle switch has been switched on and off (). In step S20), when the idle switch is switched on and off, it is determined whether or not shifting is in progress (step S30). Here, if it is determined that the engine is not shifting, it is determined whether or not the rate of change (absolute value) ΔTe of the engine torque signal Te is equal to or greater than the first predetermined value ΔTe1 (step S50).

Here, if it is determined that the rate of change (absolute value) ΔTe of the engine torque signal Te is equal to or greater than the first predetermined value ΔTe1, the flag F is set to 1 (step S60) to correct the gain of the engine torque signal Te. Gain is increased (step S70).
On the other hand, when the flag F is 0 and there is no switching between on and off of the idle switch, there is a case where shifting is in progress even with this switching, and the rate of change (absolute value) ΔTe of the engine torque signal Te is the first. When it is less than 1 predetermined value ΔTe1, the gain is not increased and the gain is set to a normal value (step S40).

Further, when the flag F is set to 1 to increase the gain, the process proceeds from step S10 to step S80, and the rate of change (absolute value) ΔTe of the torque signal Te is smaller than the first predetermined value ΔTe1. It is determined whether or not the value is less than ΔTe2, and when the rate of change (absolute value) ΔTe of the torque signal Te becomes less than the second predetermined value ΔTe2, the flag F is reset to 0 (step S90) and the gain is increased. Is stopped and the gain is set to a normal value (step S40). It should be noted that it may be determined whether or not a predetermined predetermined time has elapsed after increasing the gain, and when the predetermined time has elapsed, the gain increasing process may be stopped and the gain may be set to a normal value. ..

As described above, since the gain for gain-correcting the engine torque signal Te is increased under specific conditions, the problem caused by the engine torque signal Te being delayed with respect to the actual engine torque is solved.
That is, when the accelerator pedal is changed from depressive to depressed, it is avoided or suppressed that the lockup capacity becomes too small and the engine rotation rises excessively, and when the accelerator pedal is changed from depressed to released. It is possible to avoid or suppress the occurrence of a front-rear acceleration shock in the vehicle due to an excessive lockup capacity.

In addition, since the gain is increased only by switching the accelerator pedal between on and off (switching the idle switch off and on), the amount of operation of the accelerator pedal (depressed amount and depressed amount) is detected. The gain can be increased more easily and quickly than in the case of increasing the gain.
Further, since the gain change is regulated during the shift, it is possible to avoid the possibility that the shift control is hindered by the gain change.

[5. others]
Although the torque converter control device according to the embodiment of the present invention has been described above, the present invention is not limited to the embodiment.
For example, in the above embodiment, the gain itself to be processed by the gain correction unit 59c is changed, but a gain correction unit different from the gain correction unit 59c is provided in the torque signal processing unit 59, and the correction processing is performed here. The normal value of the gain used for is set to 1, the increased value is set to a value larger than 1 by a predetermined amount, and the engine torque signal Te or the processed value thereof may be multiplied by this gain to calculate the torque value Tea. ..

Further, in the above embodiment, the gain changing unit 60 switches between on and off of the accelerator pedal, and when the time change rate ΔTe becomes the first predetermined value ΔTe1 or more, the actual engine torque suddenly increases. Judging that it is under the circumstances, the gain is increased, but it is not limited to switching between on and off of the accelerator pedal, but it detects the depression and depressing of the accelerator pedal, and the time of the engine torque signal Te. Focusing on the rate of change ΔTe, if the rate of change ΔTe over time becomes the first predetermined value ΔTe1 or more, it may be determined that the actual engine torque is rapidly increased.

1 Engine (internal combustion engine) that is the drive source
2 Torque converter 2A Torque converter body 3 Transmission mechanism 5 Automatic transmission control unit (ATCU)
7 Power transmission system 10 Automatic transmission 11 Engine output shaft (torque converter input shaft)
22 Converter housing 20 Lock-up clutch 23 Pump impeller 24 Turbine runner 25 Stator 41 Hydraulic control valve (control valve)
50A shift control unit (shift control means)
50B lockup clutch control unit (lockup clutch control means)
51 Target slip rotation calculation unit (target slip rotation calculation means)
52 Actual slip rotation calculation unit (actual slip rotation speed calculation means)
53 Slip control unit (slip control means)
53A Slip torque capacity calculation unit (slip torque capacity calculation means)
54 Feedback control unit 55 Feedforward control unit 58 Command value conversion unit 59 Torque signal processing unit as an estimated engine torque calculation unit (estimated engine torque calculation means) 60 Gain change unit (gain change means)
61 Gain change prohibition unit (gain change prohibition means)

Claims (6)

A control device installed in a vehicle that controls the slip state of a torque converter having a lockup clutch interposed between an engine and a stepped automatic transmission.
A target slip rotation calculation means for calculating a target slip rotation speed of the lockup clutch based on the driving state of the vehicle, and a target slip rotation calculation means.
A slip torque capacity calculating means for calculating the slip torque capacity of the lockup clutch from the feed forward control amount based on the target slip rotation speed and the feedback control amount based on the target slip rotation speed and the actual slip rotation speed.
An estimated engine torque calculating means for calculating an estimated engine torque by correcting the torque signal of the engine with a gain.
It is provided with an engagement command pressure calculating means for calculating the engagement command pressure of the lockup clutch from the estimated engine torque and the slip torque capacity.
A slip control device for a torque converter, comprising a gain changing means for increasing the gain by a predetermined amount when the time change rate of the torque signal becomes equal to or higher than a first predetermined value by operating the accelerator of the vehicle. The gain changing means is characterized in that, during the increase in the gain, when the rate of change of the torque signal becomes less than the second predetermined value smaller than the first predetermined value, the increase in the gain is stopped. The slip control device for a torque converter according to claim 1. The slip control device for a torque converter according to claim 1, wherein the gain changing means stops the gain increasing process after a predetermined time has elapsed after increasing the gain. The slip control device for a torque converter according to any one of claims 1 to 3, wherein the predetermined amount is a preset constant value. The slip control device for a torque converter according to any one of claims 1 to 3, wherein the predetermined amount is set to a larger value as the time change rate of the accelerator operation amount is larger. The slip control of the torque converter according to any one of claims 1 to 5, wherein the gain change prohibiting means for prohibiting the increase of the gain is provided during the shift of the stepped automatic transmission. Device.

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