JP5672938B2 - Brake control device for vehicle - Google Patents

Description

  The present invention relates to a braking control device for a vehicle.

  In Patent Document 1, in a hybrid vehicle in which an automatic transmission is interposed between an electric motor and a drive wheel, both braking forces are controlled so that the sum of the regenerative braking torque and the friction braking torque matches the required braking torque of the vehicle. A technique related to so-called regenerative cooperative control is disclosed.

JP 2006-315488 A

If the driver switches the range position of the automatic transmission from the drive range to the neutral range during the regenerative cooperative control, the automatic transmission becomes unable to transmit torque due to the release of hydraulic pressure from the manual valve of the automatic transmission. Since the braking torque is not transmitted to the driving wheel, it is necessary to increase the friction braking torque as the regenerative braking torque decreases.
At this time, if the neutral range is selected and the motor torque is set to zero at the same time, it takes time for the hydraulic oil to escape from the manual valve. There was a problem of shock.
An object of the present invention is to provide a vehicle braking control device capable of suppressing a shock when a neutral range is selected during regenerative cooperative control.

In order to achieve the above-described object, in the present invention, when a hydraulic pressure loss from the torque transmission means interposed between the electric motor and the drive wheel is detected during the regenerative cooperative control, a value less than the torque that can be transmitted by the torque transmission means. Then, the regenerative braking torque is reduced at a predetermined reduction speed that follows the decrease in the transmittable torque .

Therefore, in the present invention, the regenerative braking torque is reduced at a predetermined speed that is less than the transmittable torque of the torque transmitting means and follows the decrease in the transmittable torque. The torque fluctuation that is not performed is suppressed, and the shock of the difference in which the neutral range is selected during the regenerative cooperative control can be suppressed.

1 is an overall system diagram showing a rear-wheel drive hybrid vehicle. 2 is a control block diagram of an integrated controller 10. FIG. It is a target driving force map. It is a target charge / discharge amount map. It is a mode map. 3 is a control block diagram of regenerative cooperative control of the integrated controller 10. FIG. 3 is a flowchart showing the flow of a D → N selection change control process executed by an integrated controller 10. FIG. 5 is a time chart of torque that can be transmitted by automatic transmission AT, regeneration execution torque, target regenerative braking torque, and wheel cylinder pressure when D → N is selected.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the engine starting control apparatus of this invention is demonstrated in detail based on the Example shown on drawing.
[Example 1]
First, the drive system configuration of the hybrid vehicle will be described.
FIG. 1 is an overall system diagram showing a hybrid vehicle by rear wheel drive to which an engine start control device is applied. As shown in FIG. 1, the drive system of the hybrid vehicle in the first embodiment includes an engine E, a first clutch CL1, a motor generator (electric motor) MG, a second clutch CL2, an automatic transmission AT, and a propeller. It has a shaft PS, a differential DF, a left drive shaft DSL, a right drive shaft DSR, a left rear wheel (drive wheel) RL, and a right rear wheel (drive wheel) RR. Note that FL is the left front wheel and FR is the right front wheel.

The engine E is, for example, a gasoline engine, and the valve opening degree of the throttle valve and the like are controlled based on a control command from the engine controller 1 described later. The engine output shaft is provided with a flywheel FW.
The first clutch CL1 is a clutch interposed between the engine E and the motor generator MG, and the control created by the first clutch hydraulic unit 6 based on a control command from the first clutch controller 5 described later. Actuated by hydraulic pressure, and fastening / release including slip fastening is controlled. Specifically, the first clutch CL1 is a normally closed dry clutch that is completely engaged by the urging force of the leaf spring when not controlled. When a release command for the first clutch CL1 is output, the hydraulic pressure corresponding to the transmission torque capacity command is supplied to the piston to make a stroke, and the transmission torque capacity corresponding to the stroke amount is set. When a stroke exceeding a predetermined value is performed, contact between the clutch plates is cut off and released. Further, in order to reduce friction loss when the clutch is released, the piston is further stroked by a predetermined amount by increasing the hydraulic pressure applied to the piston even after the clutch plate is disconnected.

  On the other hand, when the first clutch CL1 is engaged from the released state, the hydraulic pressure applied to the piston is gradually lowered. Then, the piston starts a stroke, and the clutch plate starts to come into contact when the piston strokes a predetermined amount (corresponding to backlash). Incidentally, whether or not the clutch plate is in contact can be determined by whether or not the engine speed Ne has started increasing. Thereafter, the lower the hydraulic pressure acting on the piston, the higher the transmission torque capacity. In the first embodiment, a normally closed dry clutch is used. However, a normally open type, a wet clutch, a multi-plate or a single plate may be used.

  The motor generator MG is a synchronous motor generator in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator, and the three-phase AC generated by the inverter 3 is generated based on a control command from a motor controller 2 described later. It is controlled by applying. The motor generator MG can operate as an electric motor that is driven to rotate by receiving power supplied from the battery 4 (hereinafter, this state is referred to as “powering”), or when the rotor is rotated by an external force. Can function as a generator that generates electromotive force at both ends of the stator coil to charge the battery 4 (hereinafter, this operation state is referred to as “regeneration”). The rotor of the motor generator MG is connected to the input shaft of the automatic transmission AT via a damper (not shown).

The second clutch CL2 is a clutch interposed between the motor generator MG and the left and right rear wheels RL, RR, and is generated by the second clutch hydraulic unit 8 based on a control command from the AT controller 7 described later. The fastening / release including slip fastening is controlled by the control hydraulic pressure.
The automatic transmission AT is a transmission that automatically switches the stepped gear ratio such as 5 forward speeds, 1 reverse speed, etc. according to the vehicle speed VSP, accelerator opening APO, etc. The second clutch CL2 is a new dedicated clutch In addition to the above, some of the frictional engagement elements among the plurality of frictional engagement elements that are engaged at each gear stage of the automatic transmission AT are used.
The output shaft of the automatic transmission AT is connected to the left and right rear wheels RL and RR via a propeller shaft PS, a differential DF, a left drive shaft DSL, and a right drive shaft DSR as vehicle drive shafts. The first clutch CL1 and the second clutch CL2 are, for example, wet multi-plate clutches that can continuously control the oil flow rate and hydraulic pressure with a proportional solenoid.

This hybrid drive system has three travel modes according to the engaged / released state of the first clutch CL1.
The first travel mode is an electric vehicle travel mode (hereinafter abbreviated as “EV travel mode”) as a motor use travel mode that travels using only the power of the motor generator MG as a power source with the first clutch CL1 opened. It is.
The second travel mode is an engine use travel mode (hereinafter, abbreviated as “HEV travel mode”) in which the first clutch CL1 is engaged and the engine E is included in the power source.
In the third travel mode, the second clutch CL2 is slip-controlled while the first clutch CL1 is engaged, and the engine travel slip travel mode (hereinafter referred to as “WSC travel mode”) is performed while the engine E is included in the power source. ). This mode is a mode in which creep running can be achieved particularly when the battery SOC is low or the engine water temperature is low. When transitioning from the EV travel mode to the HEV travel mode, the first clutch CL1 is engaged and the engine is started using the torque of the motor generator MG.

The “HEV travel mode” has three travel modes of “engine travel mode”, “motor assist travel mode”, and “travel power generation mode”.
In the “engine running mode”, the driving wheels RL and RR are moved using only the engine E as a power source. In the “motor-assisted travel mode”, the drive wheels RL and RR are moved using the engine E and the motor generator MG as power sources. The “running power generation mode” causes the motor generator MG to function as a generator at the same time as the drive wheels RL and RR are moved using the engine E as a power source.
During constant speed operation or acceleration operation, motor generator MG is operated as a generator using the power of engine E. Further, during deceleration operation, braking energy is regenerated and electric power is generated by the motor generator MG and used for charging the battery 4.
Further, as a further mode, there is a power generation mode in which the motor generator MG is operated as a generator using the power of the engine E when the vehicle is stopped.

Next, the control system of the hybrid vehicle will be described.
As shown in FIG. 1, the control system of the hybrid vehicle in the first embodiment includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a first clutch controller 5, and a first clutch hydraulic unit 6. The AT controller 7, the second clutch hydraulic unit 8, the brake controller 9, and the integrated controller (regenerative cooperative control means) 10 are configured. The engine controller 1, the motor controller 2, the first clutch controller 5, the AT controller 7, the brake controller 9, and the integrated controller 10 are connected via a CAN communication line 11 that can exchange information with each other. Has been.

The engine controller 1 inputs the engine speed information from the engine speed sensor 12, and controls the engine operating point (Ne: engine speed, Te: engine torque) according to the target engine torque command from the integrated controller 10, etc. For example, to a throttle valve actuator (not shown). Information such as the engine speed Ne is supplied to the integrated controller 10 via the CAN communication line 11.
The motor controller 2 inputs information from the resolver 13 that detects the rotor rotational position of the motor generator MG, and according to a target motor generator torque command from the integrated controller 10, the motor operating point (Nm: motor generator) of the motor generator MG A command for controlling the rotation speed (Tm: motor generator torque) is output to the inverter 3. The motor controller 2 monitors the battery SOC indicating the state of charge of the battery 4, and the battery SOC information is used as control information for the motor generator MG and is supplied to the integrated controller 10 via the CAN communication line 11. Is done.

The first clutch controller 5 inputs sensor information from the first clutch hydraulic pressure sensor 14 and the first clutch stroke sensor 15, and engages / disengages the first clutch CL1 according to the first clutch control command from the integrated controller 10. A control command is output to the first clutch hydraulic unit 6. The information on the first clutch stroke C1S is supplied to the integrated controller 10 via the CAN communication line 11.
The AT controller 7 inputs information of each sensor from an accelerator switch 16, a vehicle speed sensor 17, a second clutch hydraulic pressure sensor 18, and an inhibitor switch that outputs a signal corresponding to the position of the shift lever operated by the driver. In response to the second clutch control command from 10, a command for controlling engagement / disengagement of the second clutch CL2 is output to the second clutch hydraulic unit 8 in the AT hydraulic control valve. Information on the accelerator opening APO, the vehicle speed VSP, and the inhibitor switch is supplied to the integrated controller 10 via the CAN communication line 11.
The brake controller 9 inputs sensor information from the wheel speed sensor 19 and the brake stroke sensor 20 that detect the wheel speeds of the four wheels, and a regenerative cooperative control command from the integrated controller 10. If the regenerative braking torque alone is insufficient with respect to the required braking torque of the vehicle determined from the stroke BS, the friction braking torque is controlled by controlling the brake unit (friction braking means) BU of each wheel so that the shortage is compensated by the friction braking torque. Is output. The brake unit BU applies friction braking torque to the wheels according to the wheel cylinder pressure.

The integrated controller 10 manages the energy consumption of the entire vehicle and has a function for running the vehicle with the highest efficiency. The integrated controller 10 detects the motor rotation speed Nm, and the second clutch output rotation speed N2out. Each sensor information from the second clutch output rotational speed sensor 22 for detecting the second clutch, the second clutch torque sensor 23 for detecting the second clutch transmission torque capacity TCL2 (second clutch torque), and the brake hydraulic pressure sensor 24, CAN Information obtained via the communication line 11 is input.
The integrated controller 10 also controls the operation of the engine E according to the control command to the engine controller 1, the operation control of the motor generator MG according to the control command to the motor controller 2, and the first control command to the first clutch controller 5. Engagement / release control of the clutch CL1 and engagement / release control of the second clutch CL2 by a control command to the AT controller 7 are performed.

FIG. 2 is a control block diagram of the integrated controller 10. The integrated controller 10 includes a target driving force calculation unit 100, a mode selection unit 200, a target charge / discharge calculation unit 300, an operating point command unit 400, and shift control. Part 500.
The target driving force calculation unit 100 calculates a target driving force tFoO from the accelerator opening APO and the vehicle speed VSP using the target driving force map shown in FIG.
The mode selection unit 200 selects a target mode based on the mode map. FIG. 5 shows a mode map. The mode map has an EV travel mode, a WSC travel mode, and an HEV travel mode, and calculates the target mode from the accelerator opening APO and the vehicle speed VSP. However, even if the EV travel mode is selected, if the battery SOC is equal to or lower than the predetermined value, the “HEV travel mode” or the “WSC travel mode” is forcibly set as the target mode.

The target charge / discharge calculation unit 300 calculates the target charge / discharge power tP from the battery SOC using the target charge / discharge amount map shown in FIG. In the target charge / discharge amount map, the EVON line for permitting or prohibiting the EV travel mode is set to SOC = 50%, and the EVOFF line is set to SOC = 35%.
When SOC ≧ 50%, the EV drive mode area appears in the mode map of FIG. Once the EV driving mode area appears in the mode map, this area continues to appear until the SOC drops below 35%.
When SOC <35%, the EV drive mode area disappears in the mode map of FIG. When the EV drive mode area disappears from within the mode map, this area continues to disappear until the SOC reaches 50%.

In the operating point command unit 400, from the accelerator opening APO, the target driving force tFoO, the target mode, the vehicle speed VSP, and the target charging / discharging power tP, the transient target engine torque A target motor generator torque, a target second clutch transmission torque capacity, a target gear position of the automatic transmission AT, and a first clutch solenoid current command which is a transmission torque capacity command of the first clutch CL1 are calculated.
The shift control unit 500 drives and controls the solenoid valve in the automatic transmission AT so as to achieve the target second clutch transmission torque capacity and the target shift speed according to the shift schedule shown in the shift map. The shift map is a map in which a target gear position is set in advance based on the vehicle speed VSP and the accelerator opening APO.

Next, regenerative cooperative control will be described.
FIG. 6 is a control block diagram of the regenerative cooperative control of the integrated controller 10.
The integrated controller 10 includes a target regenerative braking torque calculation unit 31 and a regenerative execution torque calculation unit 32.
The target regenerative braking torque calculation unit 31 includes a selection processing unit 31a and a rate limit processing unit 31b.
The selection processing unit 31a inputs the target motor generator torque and the target regenerative braking torque output from the rate limit processing unit 31b, and the range position of the automatic transmission AT is changed from the drive range (D range) to the neutral range during regenerative cooperative control. When switching to (N range) (hereinafter, when D → N is selected), the target regenerative braking torque output from the rate limit processing unit 31b is selected and output to the motor controller 2; otherwise, the target motor The generator torque is selected as the target regenerative braking torque and output to the motor controller 2.
The rate limit processing unit 31b outputs a target regenerative braking torque obtained by reducing the previous value (previous calculation value) of the target regenerative braking torque output from the selection processing unit 31a at a predetermined decrease rate (> 0). Here, the rate of decrease of the rate limit processing unit 31b is the actual friction braking torque relative to the target friction braking torque, which will be described later, and the oil pressure release speed when the oil pressure is released from the manual valve of the automatic transmission AT when D → N is selected. Is set in accordance with the response delay (so that the speed matches the actual rising speed of the friction braking torque). The target regenerative braking torque is set to a value that does not exceed the transmittable torque of the automatic transmission AT. Since the manual valve hydraulic pressure release speed is determined by the specifications of the brake unit BU, it can be obtained in advance by experiments or the like.

The regeneration execution torque calculation unit 32 includes a multiplier 32a, a selection processing unit 32b, and a rate limit processing unit 32c.
The multiplier 32a inputs the motor generator torque and the gear ratio of the automatic transmission AT, and outputs a value obtained by multiplying both to the selection processing unit 32b as a regeneration execution torque.
The selection processing unit 32b inputs the regenerative execution torque output from the multiplier 32a and the regenerative execution torque output from the rate limit processing unit 32c. When D → N is selected, the regeneration processing torque output from the rate limit processing unit 32c is input. The execution torque (regenerative braking torque output to the propeller shaft PS) is selected and output to the brake controller 9, otherwise the regenerative execution torque output from the multiplier 32a is selected and output to the brake controller 9. .
The rate limit processing unit 32c outputs a regenerative braking torque obtained by reducing the previous value of the regenerative execution torque output from the selection processing unit 32b at a predetermined reduction rate (> 0). Here, the rate of decrease of the rate limit processing unit 32c depends on the hydraulic pressure release speed when the hydraulic pressure is released from the manual valve of the automatic transmission AT at the time of D → N selection, and from the rate of decrease of the rate limit processing unit 31b. Also set a large value.

The motor controller 2 controls the motor generator MG so that the target regenerative braking torque output from the target regenerative braking torque calculation unit 31 is obtained.
Based on the regenerative execution torque output from the regenerative execution torque calculator 32, the brake controller 9 takes into account the regenerative execution torque (regenerative braking output to the left and right rear wheels RL, RR) in consideration of the gear ratio, tire diameter, etc. of the differential DF. Torque) is calculated. Then, the target friction braking torque is obtained by subtracting the regeneration execution torque calculated from the required braking torque of the vehicle obtained from the brake stroke BS, and the brake unit BU of each wheel is controlled so as to obtain the target friction braking torque.

[Change control process when D → N is selected]
FIG. 7 is a flowchart showing the flow of the D → N selection change control process executed by the integrated controller 10.
In step S1, it is determined whether or not the range position has been switched from the D range to the N range based on the signal from the inhibitor switch. If YES, the process proceeds to step S2, and if NO, the control is terminated. Step S1 is a hydraulic pressure drop detecting means for detecting a hydraulic pressure drop from the manual valve of the automatic transmission AT.
In step S2, it is determined whether or not the target regenerative braking torque is non-zero, that is, whether or not the target motor generator torque is negative. If YES, the process proceeds to step S3. End control.
In step S3, the selection processing unit 31a selects the target regenerative braking torque output from the rate limit processing unit 31b to bring the target regenerative braking torque close to zero with a ramp.
In step S4, the selection processing unit 32b selects the regenerative execution torque output from the rate limit processing unit 32c to bring the regenerative execution torque close to zero with a ramp.

Next, the operation will be described.
[Change control action when D → N is selected]
In hybrid vehicles with an automatic transmission interposed between the electric motor and the drive wheel, if the range position is switched from the drive range to the neutral range during regenerative cooperative control, the automatic transmission shifts automatically when the hydraulic pressure is released from the manual valve of the automatic transmission. Since the machine becomes incapable of transmitting torque and the regenerative braking torque of the electric motor is not transmitted to the drive wheels, it is necessary to increase the friction braking torque in accordance with a decrease in the regenerative braking torque. Here, the target friction braking torque is obtained by subtracting the regenerative braking torque that actually acts on the wheel from the required braking torque of the vehicle. In order to obtain the actual regenerative braking torque, the motor generator torque and the actual speed of the automatic transmission are determined. Information on the gear ratio (the ratio of actually transmitting torque, not just the ratio of the input / output rotational speed of the automatic transmission) is required.
However, since the actual gear ratio cannot be estimated while the hydraulic pressure is released from the manual valve, the actual regenerative braking torque cannot be calculated and the target friction braking torque cannot be generated.

Therefore, for example, it may be possible to reduce the motor torque to zero at the same time as switching from the drive range to the neutral range. In this case, however, it takes time for the hydraulic oil to drain from the manual valve. Then, a shock (deceleration fluctuation) occurs in the vehicle due to torque fluctuation.
On the other hand, when the target regenerative braking torque is slowly brought close to zero, if the regenerative braking torque is output even after the hydraulic pressure is completely removed, the automatic transmission cannot transmit the regenerative braking torque and the clutch is released. Therefore, there is a problem that the input rotation is reduced and the engine is stalled in the HEV travel mode, and the input rotational speed is reversely rotated in the EV travel mode. Further, when the timing when the regenerative braking torque is lost and the timing when the friction braking torque increases, a shock is generated.

On the other hand, in the first embodiment, when D → N is selected, the reduction rate of the target regenerative braking torque is set according to the hydraulic pressure release speed of the manual valve.
FIG. 8 is a time chart of transmittable torque, regenerative execution torque, target regenerative braking torque, and wheel cylinder pressure of the automatic transmission AT when D → N is selected. As shown in FIG. The value is less than the transmittable torque of the automatic transmission AT, and decreases following the decrease in the transmittable torque.
As a result, unintended torque fluctuations due to the residual pressure of the manual valve when the hydraulic pressure is released can be suppressed, and shock during D → N selection during regenerative cooperative control can be suppressed.

In the first embodiment, the reduction rate of the regenerative execution torque that determines the target friction braking torque applied to the brake unit BU is set higher than the decrease rate of the target regenerative braking torque applied to the motor generator MG. Here, if both are set to the same decrease rate, the friction braking torque that is hydraulically controlled has a low response to the regenerative braking torque, and therefore the rise of the friction braking torque is delayed with respect to the decrease in the regenerative braking torque. As a result, the actual braking torque is insufficient with respect to the required braking torque. Therefore, by making the reduction rate of the regeneration execution torque higher than the reduction rate of the target regenerative braking torque, the friction braking torque can be raised at an early stage, and the occurrence of shock due to torque fluctuations that are not intended by the driver can be suppressed. .
Furthermore, in the first embodiment, since the regenerative braking torque is reduced at a speed that matches the actual rising speed of the friction braking torque by the brake unit BU, the sum of the regenerative braking torque and the friction braking torque matches the required braking torque. Therefore, it is possible to suppress the occurrence of shock due to torque fluctuations that are not intended by the driver.

The vehicle braking control apparatus according to the first embodiment has the following effects.
(1) Between the motor generator MG and the left and right rear wheels RL and RR, a brake unit BU for applying friction braking torque to the wheels by interposing a torque transmission means (automatic transmission AT) capable of transmitting torque by hydraulic pressure, and the motor generator In a vehicle braking control device including an integrated controller 10 that controls the regenerative braking torque and the friction braking torque so that the sum of the regenerative braking torque and the friction braking torque by the MG becomes the required braking torque of the vehicle, A hydraulic pressure drop detecting means (step S1) for detecting a hydraulic pressure drop is provided, and the integrated controller 10 reduces the regenerative braking torque according to the speed of the hydraulic pressure drop when the hydraulic pressure drop is detected during the regenerative cooperative control.
As a result, unintended torque fluctuations due to the residual pressure of the manual valve when the hydraulic pressure is released can be suppressed, and shock during D → N selection during regenerative cooperative control can be suppressed.

  (2) The integrated controller 10 increases the regenerative execution torque decrease rate higher than the target regenerative braking torque decrease rate, so it can start up the friction braking torque without delay with respect to the decrease in regenerative braking torque. It is possible to suppress the occurrence of shock due to torque fluctuations that are not intended by the driver.

  (3) Since the integrated controller 10 reduces the regenerative braking torque at a speed that matches the actual rising speed of the friction braking torque, the sum of the regenerative braking torque and the friction braking torque can be matched with the required braking torque. The occurrence of shock due to unintended torque fluctuations of the driver can be suppressed.

  (4) The oil pressure drop detecting means determines that the oil pressure is lost when the range position of the automatic transmission AT is switched from the drive range to the neutral range, and can detect oil loss without adding a new sensor.

(Other examples)
The vehicle braking control device according to the present invention has been described above based on the embodiments. However, the present invention is not limited to the above-described configuration, and other configurations can be adopted without departing from the scope of the present invention. For example, in the embodiment, the FR type hybrid vehicle has been described. However, as long as the torque transmission means is interposed between the motor generator and the driving wheel, the FF type hybrid vehicle or the electric vehicle may be used. Good.
The second clutch may not be a speed change friction element existing in the automatic transmission, but a dedicated one may be newly provided. In this case, the second clutch can be provided between the input shaft of the automatic transmission and the motor / generator shaft, or can be provided between the output shaft of the automatic transmission and the rear wheel drive system.

BU brake unit (friction braking means)
MG motor generator (electric motor)
RL, RR Left and right rear wheels (drive wheels)
10 Integrated controller (regenerative cooperative control means)
S1 Oil pressure drop detection means

Claims (4)

Between the electric motor and the driving wheel, a torque transmission means capable of transmitting torque by hydraulic pressure is interposed,
Friction braking means for applying friction braking torque to the wheels;
In a vehicle braking control device including regenerative cooperative control means for controlling the regenerative braking torque and the friction braking torque so that a sum of the regenerative braking torque by the electric motor and the friction braking torque becomes a required braking torque of the vehicle. ,
Oil pressure drop detecting means for detecting oil pressure drop from the torque transmitting means is provided,
The regenerative cooperative control means is a value that is less than the transmittable torque of the torque transmitting means when the hydraulic pressure drop is detected during the regenerative cooperative control, and a predetermined decrease speed that follows the decrease in the transmittable torque. A braking control device for a vehicle , wherein the regenerative braking torque is reduced. The vehicle braking control device according to claim 1,
The regenerative cooperative control means makes the increase speed of the target value of the friction braking torque applied to the friction braking means higher than the decrease speed of the target value of the regenerative braking torque applied to the electric motor. Braking control device. In the vehicle braking control device according to claim 1 or 2,
The regenerative cooperative control means reduces the regenerative braking torque at a speed that coincides with an actual rising speed of the friction braking torque. The vehicle braking control device according to any one of claims 1 to 3,
The torque transmission means is an automatic transmission;
The brake control device for a vehicle according to claim 1, wherein the hydraulic pressure loss detecting means determines that the hydraulic pressure is lost when a range position of the automatic transmission is switched from a drive range to a neutral range.

Images