JP2007276655A - Vehicular brake control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide vehicular brake control device capable of preventing deceleration before sharing from becoming impossible to be kept due to delay of starting of hydraulic brake force at the time of starting sharing. <P>SOLUTION: Before starting sharing, a number of rotations of a motor 60 is raised so as to make a number of rotations of the motor 60 become a number of rotations capable of compensating decreasing amount of regenerative brake force when pump pressurization is started. Therefore, the amount of brake fluid supplied by a pump 39 does not run short, and W/C pressure is generated according to differential pressure instruction value of a second differential pressure control valve 36. The deceleration before sharing can be kept after sharing. Consequently, the problem that the amount of the brake fluid supplied by the pump 39 is short and starting of hydraulic brake force is delayed is not generated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention performs cooperative control of a hydraulic brake device that generates a hydraulic braking force using brake fluid and a regenerative brake device that generates a regenerative braking force using a motor generator or the like, thereby providing a braking force to a vehicle. The present invention relates to a vehicle brake control device to be generated.

  Conventionally, in Patent Document 1, a vehicle brake control device that generates a target braking force by performing cooperative control of a hydraulic braking force generated by a hydraulic brake device and a regenerative braking force generated by a regenerative braking device has been proposed. Yes. This vehicle brake control device applies a brake hydraulic pressure formed by driving a pump regardless of brake operation to a wheel cylinder (hereinafter referred to as W / C) provided to each wheel, thereby applying to the wheel. A hydraulic brake device that generates a hydraulic braking force, a regenerative brake device that generates a regenerative brake corresponding to a brake operation state detected by a brake operation state detection unit that detects a brake operation state by driving a motor generator, and a regenerative brake device. A braking force compensation means for compensating for a lack of braking force due to fluctuations in braking force is provided.

In this vehicle brake control device, when the regenerative braking force is reduced to the hydraulic braking force, the brake fluid in the master cylinder (hereinafter referred to as M / C) is sucked out by a pump provided in the hydraulic braking device. By supplying the brake fluid to the W / C side, a hydraulic braking force is generated.
JP 2006-21745 A

  However, when the regenerative braking force is switched to the hydraulic braking force as described above, the amount of brake fluid supplied by the pump at the start of the replacement is insufficient, the rise of the hydraulic braking force is delayed, and the deceleration before the replacement cannot be maintained. Problems can arise.

  An object of the present invention is to provide a vehicular brake control device that can prevent a deceleration before switching from being maintained due to a delay in rising of a hydraulic braking force at the start of switching.

  In order to achieve the above object, according to the first aspect of the present invention, the control means (70, 80) is configured such that the hydraulic brake device generates the regenerative braking force generated by the regenerative brake device during braking. It has a function of executing control for switching to power, and prior to the start of switching, the number of revolutions of the motor is increased to the number of revolutions at which the required amount of brake fluid discharged by the pump (39) can be obtained when switching. It is said.

  Thus, prior to the start of replacement, when the pressurization of the pump is started, the rotational speed of the motor is increased so that the rotational speed of the motor (60) becomes a rotational speed that can compensate for the decrease in the regenerative braking force. For this reason, the amount of brake fluid supplied by the pump does not become insufficient. Therefore, it is possible to prevent the problem that the rise of the hydraulic braking force is delayed because the amount of brake fluid supplied by the pump is insufficient.

  According to the second aspect of the present invention, the control means has vehicle speed detection means (100) for detecting the vehicle speed, and the vehicle speed detected by the vehicle speed detection means is changed from the first vehicle speed (Vs2) to the second vehicle speed (Vs3). ), When the vehicle speed detected by the vehicle speed detecting means becomes the third vehicle speed (Vs1) faster than the first vehicle speed, the vehicle speed is set to The motor is characterized in that the rotational speed of the motor is gradually increased during the period from the three vehicle speeds to the first vehicle speed.

  In this way, if the motor rotation speed is gradually increased between the time when the vehicle speed becomes the third vehicle speed and the time when the vehicle speed changes to the first vehicle speed, the motor speed is adjusted so that the rotation speed is exactly that at the start of switching. It is possible to adjust the rotational speed increase start timing. As a result, it is possible to suppress wasteful power consumption caused by rotating the motor at a high speed from an early stage.

  Specifically, as shown in claim 3, the control means includes a total change amount calculating means (200) for calculating a total change amount of the wheel cylinder pressure from the start to the end of the change, and an end from the start of the change. Per unit time by dividing the change amount of the wheel cylinder pressure obtained by the change time calculation means by the change time calculation means (210) and the change time calculation means by the change time calculation means. Unit time variation calculation means (220) for determining the amount of change in wheel cylinder pressure, and MAP or relationship indicating the relationship between the wheel cylinder pressure associated with the size of the wheel cylinder pressure variation per unit time and the rotational speed of the motor The amount of change in wheel cylinder pressure per unit time calculated by the unit time change amount calculation means (220) from the equation Motor rotation speed setting means (140) for selecting a corresponding MAP or relational expression, and using the selected MAP or relational expression to obtain a wheel cylinder pressure at the time of replacement and a rotation speed (Nm) of the corresponding motor; , And is configured.

  Thus, using the MAP or the relational expression indicating the relationship between the wheel cylinder pressure associated with the magnitude of the change amount of the wheel cylinder pressure per unit time and the rotation speed of the motor, it corresponds to the wheel cylinder pressure at the time of replacement. The number of rotations (Nm) of the motor can be obtained. If the rotational speed of the motor is increased to this rotational speed prior to replacement, the effect described in claim 1 can be obtained.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 shows a block configuration of each function of a hybrid vehicle equipped with a vehicle brake control device 1 to which the first embodiment of the present invention is applied.

  First, the hydraulic brake device in the vehicle brake control device 1 of the present embodiment will be described. As shown in FIG. 1, the vehicle brake control device 1 includes a brake pedal 11, a booster device 12, an M / C 13, W / C 14, 15, 34, 35, and an actuator for brake fluid pressure control. 50, and these constitute a hydraulic brake device. The vehicle brake control device 1 includes a brake ECU 70. The brake ECU 70 functions as part of a control unit that executes cooperative control of the hydraulic brake device and a regenerative brake device described later, so that the hydraulic braking force generated by the hydraulic brake device and the regenerative control generated by the regenerative brake device are performed. It is designed to control power. FIG. 2 is a diagram showing a detailed structure of each part constituting the hydraulic brake device.

  As shown in FIG. 2, a brake pedal 11 as a brake operation member that is depressed by a driver when applying a braking force to the vehicle is connected to a booster 12 and a M / C 13 that serve as a brake fluid pressure generation source. When the driver depresses the brake pedal 11, the stepping force is boosted by the booster 12, and the master pistons 13a and 13b disposed in the M / C 13 are pressed. Thereby, the same M / C pressure is generated in the primary chamber 13c and the secondary chamber 13d defined by the master pistons 13a and 13b.

  The M / C 13 is provided with a master reservoir 13e having passages communicating with the primary chamber 13c and the secondary chamber 13d. The master reservoir 13e supplies brake fluid into the M / C 13 through the passage, or stores excess brake fluid in the M / C 13. Each passage is blocked from the primary chamber 13c and the secondary chamber 13d when the pistons 13a and 13b are pushed.

  The M / C pressure generated in the M / C 13 is transmitted to each of the W / Cs 14, 15, 34, 35 through the brake fluid pressure control actuator 50.

  The brake fluid pressure control actuator 50 includes a first piping system 50a and a second piping system 50b. The first piping system 50a controls the brake fluid pressure applied to the left rear wheel RL and the right rear wheel RR, and the second piping system 50b controls the brake fluid pressure applied to the left front wheel FL and the right front wheel FR. The front and rear pipes are constituted by the two piping systems of the first and second piping systems 50a and 50b.

  Hereinafter, the first and second piping systems 50a and 50b will be described. However, since the first piping system 50a and the second piping system 50b have substantially the same configuration, the first piping system 50a will be described here. The description of the second piping system 50b is omitted with reference to the first piping system 50a.

  The first piping system 50a is provided with a pipeline A serving as a main pipeline that transmits the above-described M / C pressure to the W / C 14 provided in the left rear wheel RL and the W / C 15 provided in the right rear wheel RR. It has been. A W / C pressure can be generated in each of the W / Cs 14 and 15 through the pipe A.

  Further, the pipe line A is provided with a first differential pressure control valve 16 including a pressure regulating valve that can be controlled between a communication state and a differential pressure state. The valve position of the first differential pressure control valve 16 is adjusted so as to be in a communicating state in a normal brake state, and the valve position is adjusted so as to be in a differential pressure state when a current is passed through the solenoid coil. Further, the differential pressure amount formed by the first differential pressure control valve 16 is in accordance with the current value of the current flowing through the solenoid coil, and has a relation that the larger the current value, the larger the differential pressure amount.

  When the first differential pressure control valve 16 is in a differential pressure state, only when the brake fluid pressure on the W / C 14, 15 side is higher than the M / C pressure by a predetermined level or more, the W / C 14, 15 side The brake fluid is allowed to flow only from the side to the M / C 13 side. For this reason, the W / C 14 and 15 side is always maintained so as not to be higher than the M / C 13 side by a predetermined pressure or more, and the respective pipelines are protected.

  The pipe A branches into two pipes A1 and A2 downstream of the first differential pressure control valve 16 on the W / C 14 and 15 side. One of the two pipes A1 and A2 is provided with a first pressure increase control valve 17 for controlling the increase of the brake fluid pressure to the W / C 14, and the other is an increase of the brake fluid pressure to the W / C 15. A second pressure increase control valve 18 is provided for controlling the pressure.

  The first and second pressure increase control valves 17 and 18 are configured as electromagnetic valves as two-position valves that can control the communication / blocking state. When the first and second pressure-increasing control valves 17 and 18 are controlled to communicate, the M / C pressure or the brake fluid pressure due to the discharge of brake fluid from a pump 19 described later is set to W / C 14 and 15. Can be added to.

  Note that, during normal braking by the operation of the brake pedal 11 performed by the driver, the first differential pressure control valve 16 and the first and second pressure increase control valves 17 and 18 are always controlled to be in a communication state.

  The first differential pressure control valve 16 and the first and second pressure increase control valves 17 and 18 are provided with safety valves 16a, 17a and 18a, respectively, in parallel. When the brake pedal 11 is depressed by the driver when the first differential pressure control valve 16 is in the differential pressure state, the safety valve 16a of the first differential pressure control valve 16 sets the M / C pressure to W / C14, 15 is provided in order to be able to transmit to 15. The safety valves 17a and 18a of the pressure increase control valves 17 and 18 are returned to the brake pedal 11 by the driver, particularly when the pressure increase control valves 17 and 18 are controlled to be shut off during ABS control. In some cases, the W / C pressure of the left rear wheel RL and the right rear wheel RR is provided so as to be able to be reduced in response to the returning operation.

  In the pipeline A, the first and second pressure increase control valves 17 and 18 and the pipeline B serving as a pressure-reducing pipeline connecting the pressure regulating reservoir 20 between the W / Cs 14 and 15 are controlled in communication / blocking states. As a two-position valve that can be formed, a first pressure reduction control valve 21 and a second pressure reduction control valve 22 each comprising an electromagnetic valve are provided. The first and second pressure reduction control valves 21 and 22 are always cut off during normal braking.

  A conduit C serving as a reflux conduit is disposed so as to connect between the pressure regulating reservoir 20 and the conduit A serving as the main conduit. This pipe C is provided with a self-priming pump 19 driven by a motor 60 so as to suck and discharge brake fluid from the pressure regulating reservoir 20 toward the M / C 13 side or the W / C 14, 15 side. Yes.

  A safety valve 19 a is provided on the discharge port side of the pump 19 so that high-pressure brake fluid is not applied to the pump 19. Further, in order to alleviate the pulsation of the brake fluid discharged from the pump 19, a fixed capacity damper 23 is disposed on the discharge side of the pump 19 in the pipe C.

  And the pipe line D used as an auxiliary pipe line is provided so that the pressure regulation reservoir 20 and M / C3 may be connected. Brake fluid is sucked from the M / C 13 by the pump 19 through this pipeline D and discharged to the pipeline A, so that the brake fluid is supplied to the W / C 14 and 15 during TCS control or ABS control. In addition, the W / C pressure of the target wheel can be increased.

  The pressure regulating reservoir 20 is connected to the pipeline D and receives the brake fluid from the M / C 3 side, and receives the brake fluid that is connected to the pipelines B and C and escapes from the W / Cs 14 and 15. In addition, a reservoir hole 20b for supplying brake fluid to the suction side of the pump 19 is provided and communicates with the reservoir chamber 20c. A ball valve 20d is disposed inside the reservoir hole 20a. The ball valve 20d is provided with a rod 20f having a predetermined stroke for moving the ball valve 20d up and down separately from the ball valve 20d.

  Also, in the reservoir chamber 20c, there are a piston 20g interlocking with the rod 20f, and a spring 20h that generates a force for pressing the piston 20g toward the ball valve 20d to push out the brake fluid in the reservoir chamber 20c. Is provided.

  The pressure regulating reservoir 20 configured as described above is configured such that when a predetermined amount of brake fluid is stored, the ball valve 20d is seated on the valve seat 20e and the brake fluid does not flow into the pressure regulating reservoir 20. . For this reason, more brake fluid than the suction capacity of the pump 19 does not flow into the reservoir chamber 20c, and no high pressure is applied to the suction side of the pump 19.

  On the other hand, as described above, the second piping system 50b has substantially the same configuration as the first piping system 50a. That is, the first differential pressure control valve 16 and the safety valve 16a correspond to the second differential pressure control valve 36 and the safety valve 36a. The first and second pressure increase control valves 17 and 18 and the safety valves 17a and 18a correspond to the third and fourth pressure increase control valves 37 and 38 and the safety valves 37a and 38a, respectively. , 22 correspond to the third and fourth decompression control valves 41, 42, respectively. The pressure regulating reservoir 20 and the components 20a to 20h correspond to the pressure regulating reservoir 40 and the components 20a to 20h. The pump 19 and the safety valve 19a correspond to the pump 39 and the safety valve 19a. The damper 23 corresponds to the damper 43. Further, the pipeline A, the pipeline B, the pipeline C, and the pipeline D correspond to the pipeline E, the pipeline F, the pipeline G, and the pipeline H, respectively. As described above, the hydraulic piping structure in the vehicle brake control device 1 is configured.

  Further, the brake fluid pressure control actuator 50 is provided with an M / C pressure sensor 61 for detecting the M / C pressure generated in the M / C 13. A detection signal of the M / C pressure sensor 61 is output toward the brake ECU 70.

  The brake ECU 70 is configured by a known microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and executes processing such as various calculations according to a program stored in the ROM. For example, the brake ECU 70 receives a detection signal from a wheel speed sensor (not shown) that detects the wheel speed to obtain the wheel speed, obtains the vehicle speed from the wheel speed, or obtains the vehicle deceleration by differentiating the vehicle speed over time. is doing. Based on the electrical signal from the brake ECU 70, the control valves 16-18, 21, 22, 36-38, 41, 42 and the pumps 19, 39 in the brake fluid pressure control actuator 50 configured as described above are provided. Voltage application control to the motor 60 for driving is executed. Thereby, control of the W / C pressure generated in each W / C 14, 15, 34, 35 is performed.

  Specifically, in the case of performing cooperative control of the hydraulic braking force generated by the hydraulic brake device and the regenerative braking force generated by the regenerative brake device, the brake ECU 70 controls the motor 60 and the electromagnetic valve in the brake hydraulic pressure control actuator 50. When a control voltage is applied to the drive solenoid, each control valve 16-18, 21, 22, 36-38, 41, 42 in the brake fluid pressure control actuator 50 is driven according to the applied voltage. And the route of the brake pipe is set. The brake fluid pressure corresponding to the set brake pipe path is generated in the W / Cs 14, 15, 34, and 35 so that the braking force generated in each wheel can be controlled.

  For example, when the hydraulic braking force is generated for the front wheels FL, FR, the brake fluid is sucked and discharged by the pump 39 by driving the motor 60 with the second differential pressure control valve 36 in the differential pressure state. Let it be done. Accordingly, the brake fluid in the M / C 13 is sucked into the pump 39 through the pipe H and the pipe G, and is supplied to the W / Cs 34 and 35 of the front wheels FL and FR through the pipe G and the pipe E. At this time, since the differential pressure is generated on the M / C 13 side and the W / C 34, 35 side by the pressure regulating valve in the second differential pressure control valve 36, the W / C 34, 35 is pressurized, A hydraulic braking force is generated.

  As shown in FIG. 1, the hybrid vehicle includes a regenerative brake device and a hybrid ECU 80 that controls the regenerative brake device.

  The regenerative braking device includes a motor 81 connected to an axle that connects both front wheels FL and FR, an inverter 82 electrically connected to the motor 81, a battery 83 electrically connected to the inverter 82, and the like. It is said that. The motor 81 is configured, for example, as an AC synchronous type, and power is supplied to the motor 81 by converting a DC current generated by the battery 83 by the inverter 82 into an AC current. The inverter 82 plays a role of converting a direct current of the battery into an alternating current based on a control signal of the hybrid ECU 80 and a role of charging the battery 83 by converting the alternating current generated by the motor 81 into direct current.

  The hybrid ECU 80 mainly controls the drive system. The hybrid ECU 80 obtains the vehicle speed based on a detection signal from a wheel speed sensor (not shown) that detects the wheel speed, receives an output signal from an accelerator operation quantity sensor (not shown) installed on the accelerator pedal, and obtains an accelerator operation amount. The obtained vehicle speed and accelerator operation amount are stored, and the state such as whether or not the battery 83 is in a failed state or in a fully charged state is managed. Further, the hybrid ECU 80 performs calculations necessary for regenerative brake control based on the stored vehicle speed and accelerator operation amount, supplies data used for regenerative brake control to the brake ECU 70, and conversely the brake ECU 70. Receive necessary data from

  The hybrid ECU 80 performs regenerative braking control in cooperation with the brake ECU 70, controls the inverter 82, and controls the operation of the motor 81. That is, the operation of the motor 81 is controlled by the inverter 82 based on the control signal of the hybrid ECU 80, and the motor 81 is driven by the rotational force of both front wheels FL, FR (or the axle connecting them) to generate power, The battery 83 is charged with the generated electric power. Since the braking force is generated by the resistance force of the motor 81 during power generation, this is used as the regenerative braking force.

  At this time, the hybrid ECU 80 obtains an actually generated regenerative braking force (hereinafter referred to as a regenerative execution braking force) and transmits it to the brake ECU 70. Specifically, since the regenerative execution torque corresponding to the regenerative execution braking force can be obtained from the back electromotive force generated by the motor 81, the back electromotive force of the motor 81 is obtained by a known method, and the regenerative execution braking force is obtained therefrom. The corresponding regeneration execution torque is obtained. This regeneration execution torque (or the regeneration execution hydraulic pressure obtained by further converting the regeneration execution torque into a hydraulic pressure) is transmitted to the brake ECU 70.

  Next, the operation of the vehicle brake control device 1 configured as described above will be described. First, prior to description of a specific operation of the vehicle brake control device 1, the reason for performing the operation will be described.

  FIG. 3 is a graph showing the relationship between the elapsed time from the start of braking and each braking force. As shown in this figure, at the time of the start of braking, the hydraulic braking force by the M / C pressure generated in the M / C 13 based on the force obtained by boosting the operating force of the brake pedal 11 by the booster 12. On the other hand, the driver's required braking force is generated by the total braking force obtained by adding the regenerative braking force generated by the regenerative braking device. Then, the regenerative braking force is replaced with a hydraulic braking force by pump pressurization as time elapses.

  The replacement is performed when it is determined that the replacement is started in the replacement start determination executed by the brake ECU 70, and the regenerative braking force liquid is reduced by decreasing the regenerative command value sent from the brake ECU 70 to the hybrid ECU 80 or the like. Switch to pressure braking force. For example, so that the regenerative braking force can be completely replaced with the hydraulic braking force at a predetermined vehicle speed before the stop, a predetermined time before is determined as a switching start timing, and it is determined that the switching is started when that timing is reached. Alternatively, it may be determined that the replacement start timing is when the vehicle speed reaches a certain vehicle speed. There are various types of the replacement start determination other than those described here, but since they have been performed conventionally, the details are omitted.

  Then, at such replacement start timing, the amount of brake fluid supplied to the W / Cs 34 and 35 is insufficient so that the hydraulic braking force due to the pump pressurization can follow the decrease in the regenerative braking force. In order to avoid this, the motor 60 is set to a high speed in advance prior to the start of replacement.

  Specifically, the motor 60 is rotated from the start of braking, but before the regenerative braking force is replaced with the hydraulic braking force by pump pressurization, the load of the motor 60 (W / C pressure generated at that time) And the rotational speed according to the viscous resistance of the brake fluid). At this time, when the time lag of the start of the motor 60 is suppressed, the regenerative braking force and the hydraulic braking force based on the M / C pressure generated based on the boosting force by the booster 12 are used as a spare when the required braking force is not satisfied. Since the motor 60 is merely rotated for the purpose of doing this, the number of rotations according to the load is sufficiently smaller than the number of rotations required at the time of replacement. For this reason, it is necessary to increase in advance from this state to the rotational speed required at the time of switching. At this time, the rotation speed increase start timing when the rotation speed of the motor 60 is set to a high rotation speed reaches the rotation speed at which the rotation speed of the motor 60 can compensate for the decrease in the regenerative braking force when the pump pressurization is started. However, it is preferable to suppress the wasteful power consumption as much as possible since the wasteful power consumption is caused when the motor 60 is rotated at a high speed too early.

  Therefore, in the present embodiment, when the pump pressurization is started, the rotational speed of the motor 60 reaches a rotational speed that can compensate for the decrease in the regenerative braking force, and the motor 60 is configured to suppress unnecessary power consumption as much as possible. Set the rotation speed.

  Next, the motor rotation speed setting process in the regeneration cooperative control executed by the brake ECU 70 in order to set the rotation speed of the motor 60 will be described. Since the outline of regenerative cooperative control is the same as that of the prior art, only the motor rotation speed setting process different from the prior art will be described here.

  FIG. 4 is a flowchart of the motor rotation speed setting process. The motor rotation speed setting process shown in this figure is executed according to a program stored in advance in the ROM or the like of the brake ECU 70, and during braking (for example, when a brake switch (not shown) is turned on). Further, it is executed every predetermined calculation cycle.

  FIG. 5 is a timing chart showing changes in regenerative braking force and motor rotation speed when the motor rotation speed setting process is executed. In the present embodiment, as shown in FIG. 5, when the vehicle speed V becomes Vs3, the switching is completed, and when the vehicle speed V is Vs2 that is a constant speed larger than Vs3 is set as the switching start timing, Control is performed to set the time when the vehicle speed V becomes Vs1 as the rotation speed increase start timing so that the rotation speed of the motor 60 is exactly the rotation speed necessary for switching when Vs2.

  First, in step 100, input processing is executed. Specifically, the vehicle speed V is obtained based on the detection signal from the wheel speed sensor, the M / C pressure is obtained by inputting the detection signal of the M / C pressure sensor 61, or the regenerative brake control from the hybrid ECU 80 is necessary. Input various data.

  Next, in step 110, it is determined whether or not replacement is being performed, that is, the vehicle speed V exceeds Vs3 corresponding to the second vehicle speed, and the vehicle speed V is less than Vs2 corresponding to the first vehicle speed (Vs3 <V <Vs2). ). If it is before replacement, a negative determination is made here, and the routine proceeds to step 120.

  In step 120, it is determined whether or not it is immediately before the start of replacement, that is, whether or not the vehicle speed V is less than Vs1 corresponding to the third vehicle speed and the vehicle speed V is equal to or higher than Vs2 (Vs2 <V <Vs1). Then, a negative determination is made here until just before the start of replacement, and in step 130, the number of revolutions corresponding to the load of the motor 60 is set. On the other hand, if it reaches immediately before the start of replacement and an affirmative determination is made in this step, the routine proceeds to step 140.

  In step 140, the rotational speed of the motor 60 is gradually increased and set. Specifically, when the switching start timing is reached, the rotational speed of the motor 60 is increased to the rotational speed Nm determined from MAP indicating the relationship between the W / C pressure and the W / C pressure change amount DpWC per unit time. To be able to.

  Here, the W / C pressure change amount DpWC per unit time and the MAP showing the relationship between the W / C pressure and the W / C pressure change amount DpWC per unit time will be described.

  The W / C pressure change amount DpWC per unit time is obtained by dividing the change amount of the W / C pressure at the time of replacement by the time of replacement, and the W / C pressure change per unit time shown in FIG. It is calculated based on the flowchart of the calculation process of the amount DpWC.

  First, in step 200, the W / C pressure change amount at the time of replacement is calculated. The amount of change in the W / C pressure at the time of replacement means the total amount of change in the W / C pressure from the start to the end of replacement, and the regenerative execution torque received from the hybrid ECU 80 is converted into a hydraulic pressure. The required regeneration execution hydraulic pressure matches the amount of change in the W / C pressure. In the hybrid ECU 80, the regeneration execution torque may be further converted into hydraulic pressure in advance to obtain the regeneration execution hydraulic pressure, and data indicating the regeneration execution hydraulic pressure may be input to the brake ECU 70. In step 200, the brake ECU 70 performs data input processing indicating the regeneration execution hydraulic pressure.

  In the following step 210, the replacement time is calculated. The replacement time means the total time required to switch the regenerative braking force to the hydraulic braking force. The replacement time is obtained on the assumption that the time required for the vehicle speed V to decelerate from Vs2 to Vs3 becomes the replacement time, using the deceleration obtained by time differentiation of the vehicle speed. That is, the value obtained by dividing the speed difference between Vs2 and Vs3 by the deceleration at the start of switching ((Vs2-Vs3) / deceleration) is used as the switching time.

  In step 220, the total change amount of W / C pressure at the time of replacement obtained in step 200 is divided by the change time obtained in step 210 to calculate the change amount DpWC of W / C pressure per unit time.

  Further, the number of rotations of the motor 60 required at the time of replacement, that is, the required amount of brake fluid discharged has a correlation with the generated W / C pressure, and the correlation is the amount of change in the W / C pressure per unit time. It depends on DpWC. FIG. 7 shows the correlation between the W / C pressure and the motor rotational speed when the W / C pressure change amount DpWC per unit time is changed to three different stages of DpWC1 to DpWC3 (where DpWC1 <DpWC2 <DpWC3). It is a thing. As shown in this figure, in order to realize the W / C pressure change amount DpWC per unit time, the smaller the generated W / C pressure, the larger the required motor rotation speed (required brake fluid discharge). The larger the generated W / C pressure, the smaller the required motor rotation speed (the smaller the required amount of brake fluid discharged). As the W / C pressure change amount DpWC per unit time increases, even if the generated W / C pressure is the same, the required motor rotation speed increases (the required amount of brake fluid discharged) There are many).

  Accordingly, a plurality of types of MAP (or relational expressions) indicating the relationship between the W / C pressure change amount DpWC per unit time and the corresponding W / C pressure and the motor rotational speed as shown in FIG. When the W / C pressure change amount DpWC per unit time is obtained, the corresponding MAP can be selected from the stored MAPs.

  Therefore, in step 140, when the W / C pressure change amount DpWC per unit time is obtained by the arithmetic processing shown in FIG. 6 described above, the W / C pressure change amount DpWC per unit time obtained by using this is obtained. Are selected from the stored MAPs. Then, the W / C pressure at the time of replacement is obtained. Since the W / C pressure at this time is based on the M / C pressure in the M / C 13 generated based on the boosting action in the booster 12 at the time of replacement, the M / C pressure input in step 100 is used. Calculated based on C pressure.

  In this way, when the MAP corresponding to the W / C pressure change amount DpWC per unit time is selected and the W / C pressure is further obtained, the selected MAP is used to correspond to the obtained W / C pressure. The motor rotation speed to be obtained is obtained, and the rotation speed is stored as Nm.

  Then, for example, the value obtained by subtracting the number of revolutions corresponding to the load set in step 130 from the number of revolutions Nm is used as the number of revolutions required for the change until the start of switching. The amount of change in the number of revolutions per unit time is obtained by dividing by this time. The motor rotational speed is gradually increased and set so as to satisfy the rotational speed variation per unit time. For example, if it is immediately before the start of replacement, the process of step 140 is executed for each calculation cycle. Therefore, the rotation speed change amount per calculation cycle is obtained as the rotation speed change amount per unit time, and the process of step 140 is performed. Is executed, the number of revolutions of the motor 60 is increased by the amount of change in the number of revolutions per calculation cycle.

  In this way, when the rotation speed of the motor 60 is increased and the replacement start timing is reached, an affirmative determination is made in step 110. In this case, the routine proceeds to step 150 where the rotational speed of the motor 60 is set to Nm.

  In Steps 130 to 150 described above, when the rotational speed of the motor 60 is set, the process proceeds to Step 160 and corresponds to the rotational speed set for the motor 60 so as to be the set rotational speed. Let the current of the current value flow.

  As a result, as shown in FIG. 5, since the rotation speed of the motor 60 can be controlled to the rotation speed required at the time of replacement, the amount of brake fluid supplied by the pump 39 is insufficient. The problem that the rise of the pressure braking force is delayed can be prevented.

  As described above, according to the vehicle brake control device 1 of the present embodiment, the rotation speed of the motor 60 can compensate for the decrease in the regenerative braking force when the pump pressurization is started prior to the start of replacement. Thus, the rotational speed of the motor 60 is increased. For this reason, the amount of brake fluid supplied by the pump 39 is not insufficient, and the W / C pressure according to the differential pressure command value of the second differential pressure control valve 36 can be generated, and the deceleration before replacement can be reduced even after replacement. Can be maintained. Therefore, it is possible to prevent a problem that the rise of the hydraulic braking force is delayed due to a shortage of the brake fluid supplied by the pump 39.

  In addition, the rotational speed increase start timing of the motor 60 is adjusted so that the rotational speed is exactly the same at the start of replacement. As a result, it is possible to suppress wasteful power consumption caused by rotating the motor 60 at a high speed from an early stage.

  In the present embodiment, the rotational speed increase start timing when the rotational speed of the motor 60 is increased prior to the replacement is when the vehicle speed V becomes Vs1, but depending on the setting of Vs1, the rotational speed of the motor 60 is increased. The slope of the rise is determined. This inclination is related to the magnitude of noise associated with the rotation of the motor 60 and the amount of brake fluid sucked into the M / C 13 when the pump 19 is driven, that is, the amount of the brake pedal 11 drawn. It will be decided in consideration.

(Other embodiments)
In the above-described embodiment, the configuration in which the motor 81 is directly connected to the wheels FL, FR or the axles thereof is shown. The present invention can be applied even to such a vehicle.

  In the above embodiment, the control unit is configured by the brake ECU 70 and the hybrid ECU 80. However, the control unit may be configured together with other ECUs. Moreover, each function which brake ECU70 and hybrid ECU80 demonstrated in the said embodiment have shown as an example, and each function may be implement | achieved by ECU by integrating these, and other than these two An ECU, for example, may be configured such that a functional unit that realizes each function described above is partially provided in another ECU.

  Further, although the brake pedal 11 has been described as an example of the brake operation member, a brake lever may be used. Further, the driver's required braking force corresponding to the operation of the brake operating member is obtained based on the detection signal of the M / C pressure sensor 61, but other devices that generate an output corresponding to the driver's required braking force. For example, you may obtain | require based on the detection signal of the treading force sensor which detects the treading force of the brake pedal 11.

  The steps shown in each figure correspond to means for executing various processes. For example, in the brake ECU 70, the part that executes the process of step 140 corresponds to the motor speed setting means, the part that executes the process of step 200 corresponds to the total change amount calculating means, and executes the process of step 210. The portion corresponds to the switching time calculation means, and the portion that executes the processing of step 220 corresponds to the unit time change amount calculation means.

It is the figure which showed the block structure of each function of the hybrid vehicle by which the vehicle brake control apparatus 1 in 1st Embodiment of this invention is mounted. It is the figure which showed the detailed structure of each part which comprises a hydraulic brake device. It is a graph showing the relationship between the elapsed time from the start of braking and each braking force. It is a flowchart of a motor rotation speed setting process. 6 is a timing chart showing changes in regenerative braking force and motor rotation speed when a motor rotation speed setting process is executed. It is calculated based on the flowchart of the calculation process of the W / C pressure change amount DpWC per unit time. It is the graph which described the correlation of W / C pressure and motor rotation speed with respect to W / C pressure change amount DpWC per unit time.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Brake control apparatus for vehicles, 11 ... Brake pedal, 12 ... Booster,
13 ... M / C, 14, 15, 34, 35 ... W / C, 16, 36 ... Differential pressure control valve,
19 ... pump, 50 ... brake hydraulic pressure control actuator, 60 ... motor,
61 ... M / C pressure sensor, 70 ... Brake ECU, 80 ... Hybrid ECU,
81: Motor, 82: Inverter, 83: Battery.

Claims (3)

A booster (12) for boosting the brake operating force when the driver operates the brake operating member (11), a master cylinder (13) for generating a master cylinder pressure corresponding to the boosted force, By applying a wheel cylinder pressure based on the master cylinder pressure, a wheel cylinder (14, 15, 34, 35) that generates a hydraulic braking force for each wheel (FL to RR), It has a pump (19, 39) that pressurizes the wheel cylinder by sucking and discharging brake fluid toward the wheel cylinder, and a motor (60) for driving the pump. A hydraulic brake device that generates a hydraulic braking force based on a wheel cylinder pressure applied to the wheel cylinder;
A regenerative braking device (81-83) that generates a regenerative braking force by applying a resistance force based on a power generation to the wheel by generating a power based on the rotational force of the wheel;
Control means (70, 80) for controlling the hydraulic braking force generated by the hydraulic brake device and the regenerative braking force generated by the regenerative brake device by performing coordinated control of the hydraulic brake device and the regenerative brake device. And having
The control means has a function of executing control to switch the regenerative braking force generated by the regenerative braking device to the hydraulic braking force generated by the hydraulic brake device during braking, and to start the replacement The vehicle brake control device is configured to increase the rotational speed of the motor to a rotational speed at which a required amount of brake fluid discharged by the pump is obtained before the replacement. The control means includes vehicle speed detection means (100) for detecting the vehicle speed, and the vehicle speed detected by the vehicle speed detection means is reduced during the period from the first vehicle speed (Vs2) to the second vehicle speed (Vs3). When the vehicle speed detected by the vehicle speed detection means reaches a third vehicle speed (Vs1) that is faster than the first vehicle speed, the rotation speed increase start timing of the motor is set to the third speed. 2. The vehicle brake control device according to claim 1, wherein the number of rotations of the motor is gradually increased until the vehicle speed changes to the first vehicle speed. 3. The control means includes
Total change amount calculating means (200) for calculating a total change amount of the wheel cylinder pressure from the start to the end of the replacement;
Replacement time calculating means (210) for calculating a replacement time from the start to the end of the replacement;
A unit time change amount for determining a wheel cylinder pressure change amount per unit time by dividing a change amount of the wheel cylinder pressure obtained by the wheel cylinder pressure change amount calculating unit by the change time obtained by the change time calculating unit. Computing means (220);
The unit time determined by the unit time change amount calculation means from a MAP or a relational expression indicating the relationship between the wheel cylinder pressure and the rotation speed of the motor associated with the magnitude of the wheel cylinder pressure change amount per unit time. The MAP or the relational expression corresponding to the hit wheel cylinder pressure change amount is selected, and the rotation of the motor corresponding to the wheel cylinder pressure at the time of replacement is selected using the selected MAP or the relational expression. The vehicle brake control device according to claim 1, further comprising: a motor rotation number setting unit (140) for obtaining a number (Nm).

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