JP2016008705A - Power transmission control device - Google Patents

Abstract

A power transmission control device capable of preventing a vehicle mounted with an AMT from slipping down without increasing the number of devices mounted on the vehicle.
When the ECU determines that the vehicle is stopped on an uphill surface (step S1), the ECU calculates a braking torque necessary for the vehicle to remain stopped (step S2). A required drive torque corresponding to the braking torque is calculated (step S6), and the clutch is controlled so that the required drive torque is transmitted to the clutch (step S7).
[Selection] Figure 5

Description

  The present invention relates to a power transmission control device for a vehicle provided with an automatic stepped transmission.

  Conventionally, as a power transmission control device for a vehicle provided with an automatic manual transmission (hereinafter referred to as “AMT”), for example, in Patent Document 1, a brake device that applies braking force to wheels, and a brake There has been proposed an actuator that drives an apparatus and a control apparatus that controls the actuator, and the control means controls the actuator to release the brake device in conjunction with the clutch being connected. Yes.

  With the configuration described above, the one proposed in Patent Document 1 is such that a vehicle stopped on a running surface that is inclined so as to rise in the traveling direction is retracted in the direction opposite to the traveling direction while stopping or starting. So-called sliding down was prevented.

JP 2004-82996 A

  However, the one proposed in Patent Document 1 requires an actuator for controlling the parking brake and a hill hold device for holding the brake hydraulic pressure in order to prevent the vehicle from sliding down only by the braking force by the brake. There is a problem that the number of devices to be mounted increases.

  Therefore, the present invention has been made to solve such a problem, and a power transmission control device capable of preventing a vehicle mounted with an AMT from slipping down without increasing the number of devices mounted on the vehicle. The purpose is to provide.

  One aspect of the power transmission control device according to the present invention for solving the above-mentioned problems is a vehicle power transmission control device provided with an automatic stepped transmission, which is transmitted from a drive source of the vehicle to the automatic stepped transmission. A clutch control unit that controls the clutch so as to change the driving torque, and a necessary braking torque calculation unit that calculates a braking torque necessary for the vehicle to maintain a stop state based on a gradient in a traveling direction on the traveling surface of the vehicle The clutch control unit provides a drive torque according to the braking torque calculated by the required braking torque calculation unit on the condition that the vehicle is stopped on a traveling surface that is inclined so as to rise in the traveling direction. The clutch is controlled to be transmitted to the clutch.

  Thus, the present invention can provide a power transmission control device that can prevent a vehicle mounted with an AMT from sliding down without increasing the number of devices mounted on the vehicle.

FIG. 1 is a functional block diagram showing a main part of a vehicle equipped with a power transmission control device according to an embodiment of the present invention. FIG. 2 is a conceptual diagram showing a necessary braking torque map referred to by the power transmission control device according to the embodiment of the present invention. FIG. 3 is a conceptual diagram showing a torque correction coefficient map referred to by the power transmission control device according to the embodiment of the present invention. FIG. 4 is a conceptual diagram showing a drive torque map referred to by the power transmission control device according to the embodiment of the present invention. FIG. 5 is a flowchart showing a power transmission control operation of the power transmission control device according to the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, a vehicle 1 equipped with a power transmission control device according to an embodiment of the present invention is driven from an internal combustion engine type engine 2 as a drive source of the vehicle 1, an AMT 3, and the engine 2 to the AMT 3. A clutch 4 for transmitting torque, a drive wheel 5 for transmitting driving torque, a braking device 6 for braking the vehicle 1, and an electronic control unit (hereinafter referred to as "ECU") 7 are included. Composed.

  In the present embodiment, the engine 2 is configured by a four-cycle engine in which a series of four strokes including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke is performed, and ignition is performed during the compression stroke and the expansion stroke. Has been.

  The AMT 3 has, for example, a transmission mechanism equivalent to a constantly meshing manual transmission, and a gear stage is formed by a plurality of actuators (not shown) controlled by the ECU 7.

  The clutch 4 has an input side disk connected to the output shaft of the engine 2 and an output side disk connected to the input shaft of the AMT 3. The clutch 4 is configured such that the degree of engagement between the input side disk and the output side disk (hereinafter simply referred to as “clutch engagement degree”) is changed by an actuator controlled by the ECU 7. The frictional force with the disk is changed, and the drive torque transmitted from the engine 2 to the AMT 3 is changed.

  The braking device 6 is configured by, for example, a disc brake or a drum brake provided for each of a plurality of wheels including the drive wheels 5. The braking device 6 brakes the vehicle 1 by braking each wheel according to the operation of the brake pedal 10 via a brake booster and an actuator (not shown).

  The ECU 7 includes a computer unit including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an input port, an output port, and a network module. ing.

  The network module can communicate with other ECUs via an in-vehicle LAN (Local Area Network) conforming to a standard such as CAN (Controller Area Network) or FlexRay.

  The ROM of the ECU 7 stores a program for causing the computer unit to function as the ECU 7 along with various control constants and various maps. That is, in the ECU 7, when the CPU executes a program stored in the ROM, the computer unit functions as the ECU 7.

  The input port of the ECU 7 includes a gradient sensor 11 that detects the gradient of the traveling surface of the vehicle, a vehicle weight sensor 12 that detects the weight of the vehicle 1, and a brake that detects the operation amount of the brake pedal 10 that operates the braking device 6. Various sensors including a position sensor 13, an accelerator position sensor 15 that detects an operation amount of the accelerator pedal 14, and a vehicle speed sensor 16 that detects a vehicle speed are connected. Here, the weight of the vehicle 1 detected by the vehicle weight sensor 12 includes the weight of a load such as an occupant, a load and fuel in addition to the weight of the vehicle 1 body, and is hereinafter referred to as “actual vehicle weight”.

  Various control objects such as an actuator for controlling the clutch 4 are connected to the output port of the ECU 7. The ECU 7 is configured to control various control objects connected to the output port based on information obtained from various sensors connected to the input port.

  In the present embodiment, the gradient sensor 11 is configured by an acceleration sensor. The vehicle weight sensor 12 detects the actual vehicle weight according to the state of the suspension provided for each wheel, for example.

  The actual vehicle weight can also be calculated based on the change amount of the vehicle speed with respect to the change amount of the required output for the engine 2 when the vehicle 1 is accelerated or decelerated. In this case, the vehicle weight sensor 12 is configured by the ECU 7.

  The vehicle speed sensor 16 is constituted by, for example, a wheel speed sensor that detects the wheel speed of a driven wheel excluding the drive wheel 5 among a plurality of wheels, and the ECU 7 averages the wheel speed detected by the wheel speed sensor. The vehicle speed is calculated.

  In the present embodiment, the ECU 7 constitutes a clutch control unit 20 that controls the clutch so as to change the drive torque transmitted from the engine 2 to the AMT 3. Further, the ECU 7 calculates a required braking torque for calculating a braking torque (hereinafter referred to as “necessary braking torque”) necessary for the vehicle 1 to maintain the stop state based on the gradient in the traveling direction on the traveling surface of the vehicle 1. Part 21 is configured.

  Specifically, the ECU 7 calculates a traveling direction gradient on the traveling surface of the vehicle 1 based on the gradient detected by the gradient sensor 11. As shown in FIG. 2, the ROM of the ECU 7 stores a necessary braking torque map that represents the relationship between the traveling direction gradient on the traveling surface of the vehicle 1 and the necessary braking torque. The necessary braking torque map is experimentally determined in advance. The ECU 7 refers to the necessary braking torque map and determines the necessary braking torque corresponding to the gradient in the traveling direction on the traveling surface of the vehicle 1.

  In the present embodiment, the ECU 7 corrects the braking torque necessary for the vehicle 1 to maintain the stop state based on the actual vehicle weight. Specifically, as shown in FIG. 3, the ROM of the ECU 7 has a torque correction coefficient representing the relationship between the actual vehicle weight and a coefficient for correcting the required braking torque (hereinafter also simply referred to as “torque correction coefficient”). Contains the map. The necessary braking torque correction map is experimentally determined in advance.

  The ECU 7 refers to the torque correction coefficient map and determines a torque correction coefficient corresponding to the actual vehicle weight detected by the vehicle weight sensor 12. Further, the ECU 7 multiplies the required braking torque determined with reference to the required braking torque map shown in FIG. 2 by the torque correction coefficient determined with reference to the torque correction coefficient map shown in FIG. The necessary braking torque is corrected.

  In the present embodiment, the ECU 7 determines that the necessary braking torque is applied to the braking device when the vehicle 1 is stopped on a traveling surface that is inclined so as to rise in the traveling direction (hereinafter also simply referred to as “climbing surface”). The clutch 4 is controlled so that a driving torque obtained by subtracting the braking torque from the braking device 6 from the required braking torque is transmitted to the clutch 4 on condition that the braking torque is larger than the braking torque by the clutch 6.

  Specifically, the ECU 7 specifies the braking torque by the braking device 6 based on the operation amount of the brake pedal 10 detected by the brake position sensor 13 on the condition that the vehicle 1 maintains the stop state. When the necessary braking torque is larger than the braking torque by 6, the clutch 4 is controlled so that the driving torque obtained by subtracting the braking torque by the braking device 6 from the necessary braking torque is transmitted to the clutch 4.

  When the ECU 7 calculates the drive torque to be transmitted to the clutch 4, the degree of clutch engagement is changed via the actuator so that the calculated drive torque is transmitted from the engine 2 to the AMT 3.

  Specifically, as shown in FIG. 4, the ROM of the ECU 7 stores a drive torque map that represents the relationship between the clutch engagement degree and the drive torque when the engine 2 is in the idle operation state. The drive torque map is experimentally determined in advance. The ECU 7 refers to the drive torque map and determines the clutch engagement degree corresponding to the calculated drive torque.

  In this way, the ECU 7 adjusts the degree of clutch engagement on the condition that the vehicle 1 maintains the stop state. Note that when the ECU 7 determines that the accelerator pedal is on based on the operation amount of the accelerator pedal 14 detected by the accelerator position sensor 15, the degree of clutch engagement is set so that the vehicle 1 maintains the stop state. Is switched from the state where the adjustment of the clutch is performed to the state where the degree of clutch engagement is adjusted according to the operating state of the engine 2 and the change state of the gear position of the AMT 3.

  The power transmission control operation of the power transmission control device according to the embodiment of the present invention configured as described above will be described with reference to FIG. The power transmission control operation described below starts when the ECU 7 determines that the vehicle 1 has stopped based on the vehicle speed detected by the vehicle speed sensor 16.

  First, the ECU 7 determines whether or not the vehicle 1 is stopped on the uphill surface based on the gradient detected by the gradient sensor 11 (step S1). Here, if it is determined that the vehicle 1 has not stopped on the uphill surface, the ECU 7 ends the power transmission control operation.

  On the other hand, when it is determined that the vehicle 1 is stopped on the uphill surface, the ECU 7 refers to the necessary braking torque map shown in FIG. 2 and the necessary braking corresponding to the traveling direction gradient on the traveling surface of the vehicle 1. By determining the torque, referring to the torque correction coefficient map shown in FIG. 3, determining the torque correction coefficient corresponding to the actual vehicle weight detected by the vehicle weight sensor 12, and multiplying the necessary braking torque by the torque correction coefficient, The required braking torque is calculated (step S2).

  Next, the ECU 7 determines whether or not the accelerator pedal is on based on the operation amount of the accelerator pedal 14 detected by the accelerator position sensor 15 (step S3). Here, when it is determined that the accelerator pedal is in the on state, the ECU 7 ends the power transmission control operation.

  On the other hand, when determining that the accelerator pedal is not in the on state, the ECU 7 specifies the braking torque by the braking device 6 according to the operation amount of the brake pedal 10 detected by the brake position sensor 13 (step S4).

  Next, the ECU 7 determines whether or not the necessary braking torque calculated in step S2 is larger than the braking torque by the braking device 6 specified in step S4 (step S5). If the ECU 7 determines that the required braking torque is not greater than the braking torque generated by the braking device 6, the ECU 7 returns the power transmission control operation to step S3.

  On the other hand, when determining that the required braking torque is larger than the braking torque by the braking device 6, the ECU 7 calculates the required driving torque to be transmitted to the clutch 4 by subtracting the braking torque by the braking device 6 from the required braking torque. (Step S6).

  Next, the ECU 7 refers to the drive torque map shown in FIG. 4 and controls the clutch 4 to transmit the requested drive torque calculated in step S6 to the clutch 4 (step S7), and the power transmission control operation is performed in step S3. Return to.

  As described above, the present embodiment controls the clutch 4 so that the driving torque according to the braking torque necessary for the vehicle 1 to maintain the stop state is transmitted to the clutch 4. Can be prevented.

  In other words, the present embodiment does not require an actuator for controlling the parking brake and a hill hold device for holding the brake hydraulic pressure. Therefore, without increasing the number of devices mounted on the vehicle, it is possible to prevent the vehicle mounted with AMT from falling. Can be prevented.

  Further, in the present embodiment, the clutch 4 is controlled so that the driving torque further corresponding to the braking torque by the braking device 6 is transmitted to the clutch 4. More specifically, in this embodiment, the vehicle 1 is maintained in the stopped state on condition that the braking torque necessary for the vehicle 1 to maintain the stopped state is larger than the braking torque by the braking device 6. The clutch 4 is controlled so that the driving torque obtained by subtracting the braking torque from the braking device 6 from the necessary braking torque is transmitted to the clutch 4.

  Therefore, in the present embodiment, the clutch engagement degree is set so that the driving torque that compensates for the shortage of the braking torque due to the operation of the brake pedal 10 with respect to the braking torque necessary for the vehicle 1 to maintain the stop state is transmitted to the clutch 4. Therefore, the vehicle 1 can be prevented from sliding down due to an erroneous operation of the brake pedal 10 while the vehicle is stopped, and the vehicle 1 in a stopped state can be started smoothly.

  Further, in the present embodiment, since the braking torque necessary for the vehicle 1 to maintain the stop state is corrected based on the actual vehicle weight, the actual vehicle weight varies depending on the weight of the load such as an occupant, a load, and fuel. Even so, the vehicle 1 can be prevented from sliding down.

  In the present embodiment, the ECU 7 has been described as correcting the braking torque necessary for the vehicle 1 to maintain the stop state based on the actual vehicle weight. However, the occupant, the load and the fuel of the vehicle 1 are described. This correction may be omitted when the weight of the load such as is negligible with respect to the horsepower of the vehicle 1. In this case, the actual vehicle weight may be reflected as a constant in the necessary braking torque map.

  In the present embodiment, the ECU 7 is described as calculating the necessary braking torque based on the gradient in the traveling direction on the traveling surface of the vehicle 1. However, the ECU 7 is necessary in consideration of errors due to various factors. The braking torque may be calculated higher. In this case, for example, the necessary braking torque in the necessary braking torque map may be set higher.

  Although the embodiments of the present invention have been disclosed above, it is obvious that those skilled in the art can make modifications without departing from the scope of the present invention. All such modifications and equivalents are intended to be included in the claims recited in the claims.

1 vehicle 2 engine (drive source)
3 AMT (automatic stepped transmission)
4 Clutch 6 Braking device 20 Clutch control unit 21 Required braking torque calculation unit

Claims (4)

A power transmission control device for a vehicle provided with an automatic stepped transmission,
A clutch control unit for controlling a clutch to change a driving torque transmitted from the driving source of the vehicle to the automatic stepped transmission;
A necessary braking torque calculation unit that calculates a braking torque necessary for the vehicle to maintain a stop state based on a gradient in a traveling direction on the traveling surface of the vehicle;
The clutch control unit generates a drive torque corresponding to the braking torque calculated by the required braking torque calculation unit on the condition that the vehicle is stopped on a traveling surface inclined so as to rise in the traveling direction. A power transmission control device for controlling the clutch so as to be transmitted to the clutch.   The power transmission control device according to claim 1, wherein the clutch control unit controls the clutch so as to transmit a driving torque further corresponding to a braking torque by the braking device of the vehicle to the clutch.   The clutch control unit is configured to calculate the braking torque required for the vehicle to maintain the stopped state from the braking torque required for the vehicle to maintain the stopped state on condition that the braking torque required for the vehicle to maintain the stopped state is larger than the braking torque generated by the braking device. The power transmission control device according to claim 2, wherein the clutch is controlled so that a driving torque obtained by reducing a braking torque by the braking device is transmitted to the clutch.   The said required braking torque calculation part correct | amends the braking torque required in order for the said vehicle to maintain the said stop state based on the weight of the said vehicle. Power transmission control device.

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