JP2007216767A - Vehicular brake control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular brake control device which reduces the power consumption when a W/C (wheel cylinder) is pressurized, based on a capacitor during failure of the power supply system compared with during regular braking operation with an power supply system not in failure. <P>SOLUTION: A motor is driven only for one piping system during the failure of a power supply system. Since the braking force is generated by applying the W/C pressure using the motor even during the failure of the power supply system, the braking force as large as possible is generated while reducing the power system compared with during the regular braking. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle brake control device capable of generating pressure (hereinafter referred to as W / C pressure) in a wheel cylinder (hereinafter referred to as W / C pressure) by pressurization by a pump.

Conventionally, in Patent Document 1, one pump is provided corresponding to each wheel, one motor is provided for each piping system, and two pumps of each piping system are driven by each motor. Brake-by-wire vehicle brake control devices have been proposed.
JP-A-10-203338

  In the brake-by-wire vehicle brake control device as described above, basically, a motor for driving a control valve and a pump provided in each piping system is driven based on power supply from a battery.

  When an abnormality (for example, battery exhaustion) occurs and power supply from the battery cannot be performed (hereinafter, this state is referred to as a power system failure), the backup capacitor is charged. Electric power is supplied based on the measured voltage, and a motor for driving a control valve and a pump provided in each piping system is driven.

  In this way, when the power supply system fails, the W / C pressurization based on the driver's brake pedal operation can be gradually changed from the W / C pressurization by the motor drive.

  However, if the same operation as when power can be supplied from the battery when the power supply system fails, the capacitor capacity must be increased. For this reason, it is desired to reduce the power consumption as much as possible. In particular, when the pumps provided in each of the two piping systems constituting the vehicle brake control device are driven by two different motors, the motor consumes a large amount of power, and there is a need to reduce the power consumption. high.

  In view of the above points, the present invention makes it possible to reduce power consumption when performing W / C pressurization based on a capacitor when the power supply system fails, compared to when the normal braking is not performed when the power supply system fails. For the purpose.

  In order to achieve the above object, according to the first aspect of the present invention, a system pressurized by the first and second pumps (7, 8) is used as a first piping system, and the first piping system is provided with the first piping system. 1. The second pump (7, 8) is driven by the first motor (11), and the system pressurized by the third and fourth pumps (9, 10) is defined as the second piping system. By driving the third and fourth pumps (9, 10) provided in the system with the second motor (12), the first, second and rear wheels for the front wheels provided in the first and second piping systems The first to fourth pressure regulating circuits (H1 to H4) and the first to first pressure circuits that serve as conduits for pressurizing the first and second wheel cylinders (6FL to 6RR) and returning the brake fluid to the reservoir (3f) First to fourth linear valves (SLFR, SLRL, LFL, SLRR) is applied to a vehicle brake control device that regulates each wheel cylinder pressure, and the control means (100) operates the brake operation member (1) based on the operation amount sensor (2). When it is detected, the target braking force corresponding to the operation amount obtained by the operation amount sensor (2) is obtained, and from the battery (20) or the capacitor (21) to generate the target braking force. A power supply system that drives the first and second motors (11, 12) and the pressure regulating means (SLFR, SLRL, SLFL, SLRR) based on the power supply, and further cannot supply power from the battery (20) At the time of failure, based on the power supply of the capacitor (21), the first and second motors (11, 12) are connected to only one of the first and second piping systems. It is characterized by pressurizing the wheel cylinder pressure by the pump pressure by the discharge of the liquid.

  In this way, when the power supply system fails, the motor is driven only for one piping system. For this reason, even when the power supply system fails, the braking force can be generated by pressurizing the wheel cylinder pressure using the motor. Therefore, as much braking force as possible can be achieved while reducing power consumption compared to normal braking. Can be generated.

  In the invention according to claim 2, the primary piston (3c) and the secondary piston (3d), the primary chamber (3a) and the secondary chamber (3b) partitioned by these, the primary chamber (3a) and the secondary chamber (3b) ) Has a master reservoir (3f) corresponding to a reservoir storing brake fluid, and the brake operation member (1) is operated to operate a push rod connected to the brake operation member (1). A master cylinder (3) configured to generate a master cylinder pressure for the primary chamber (3a) and the secondary chamber (3b) when the primary piston (3c) and the secondary piston (3d) are pushed; The chamber (3a) is located downstream of the front wheel first pump (7) in the front wheel first wheel cylinder (6FR). A first auxiliary valve (A, E) and a first control valve which are provided in the first auxiliary pipeline (A, E) and which controls communication / blocking of the first auxiliary pipeline (A, E) (SNO1), a second auxiliary pipe (B, F) connecting the secondary chamber (3b) to the front wheel second wheel cylinder (6FL) on the downstream side of the front wheel second pump (9), and a second auxiliary Generated in the master cylinder (3) by providing the second control valve (SNO2) for controlling the communication / blocking of the second auxiliary pipeline (B, F) provided in the pipeline (B, F) Each wheel cylinder (6FL to 6RL) can be pressurized with the master cylinder pressure.

  In such a configuration, the control means (100) pressurizes the wheel cylinder pressure by pump pressurization by the discharge of the brake fluid of the first and second motors (11, 12) in the first and second piping systems. For the first piping system, the first and second control valves (SNO1, SNO2) are shut off, and for the one that does not pressurize the wheel cylinder pressure by pump pressurization, the first and second control valves (SNO1, With respect to the piping system for pressurizing the wheel cylinder pressure by pump pressurization by discharging the brake fluid of the first and second motors (11, 12) of the first and second piping systems, The wheel cylinder pressure is generated by the master cylinder pressure generated based on the operation of the brake operation member (1) through the first auxiliary pipe (A, E) or the second auxiliary pipe (B, F). It is characterized in that to be pressurized.

  As described above, with respect to the other piping system, the braking force is generated by the master cylinder pressure based on the operation amount of the brake operation member (1). For this reason, it becomes possible to generate a larger braking force than when no braking force is generated for the other piping system.

  In this case, as shown in claim 3, the wheel cylinder pressure is not increased by pump pressurization by the discharge of brake fluid of the first and second motors (11, 12) in the first and second piping systems. With respect to the piping system, only the front wheel wheel cylinders (6FR, 6FL) that require a braking force in particular can be pressurized by the master cylinder pressure.

  For example, as shown in claim 4, the third control valve (SWC1) for controlling communication / blocking between the first linear valve (SLFR) and the master reservoir (3f) in the first pressure regulating pipe (H1). And the third pressure regulating pipe (H3) includes a fourth control valve (SWC2) that controls communication / blockage between the third linear valve (SLFL) and the master reservoir (3f), and includes control means ( 100), the third piping system that pressurizes the wheel cylinder pressure by the pump pressurization by the discharge of the brake fluid of the first and second motors (11, 12) of the first and second piping systems. The fourth control valves (SWC1, SWC2) are set in a communicating state, and the third and fourth control valves (SWC1, SWC2) are set in a shut-off state for the piping system that does not increase the wheel cylinder pressure by pump pressurization. Thereby, it can be set as the form which pressurizes only the wheel cylinder (6FR, 6FL) for front wheels with a master cylinder pressure.

  Further, as shown in claim 5, in the first and second piping systems, the piping which does not pressurize the wheel cylinder pressure by pump pressurization by the discharge of the brake fluid of the first and second motors (11, 12). Regarding the system, both the front wheel wheel cylinders (6FR, 6FL) and the rear wheel wheel cylinders (6RL, 6RR) may be pressurized by the master cylinder pressure.

  For example, as shown in claim 6, in the main pipeline (C, G, G1 to G4), on the upstream side of the connection point with the first to fourth pressure regulating circuits (H1 to H4), the master reservoir ( 3f) and a first control wheel (SWC1) for controlling communication / blocking between the first front wheel and first rear wheel wheel cylinders (6FR, 6RL) in the first piping system, and a master reservoir (3f) And a second control valve (SWC2) for controlling communication / blocking between the second front wheel wheel cylinders (6FL, 6RR) in the second piping system, and the first and second piping systems. Of these, the third and fourth control valves (SWC1, SWC2) are in communication with respect to the piping system that pressurizes the wheel cylinder pressure by pump pressurization by the discharge of brake fluid from the first and second motors (11, 12). , Pump pressurization Regarding more piping system who do not pressurize the wheel cylinder pressure and the third, fourth control valve (SWC1, SWC2) the cut-off state. Thereby, both the front wheel wheel cylinders (6FR, 6FL) and the rear wheel wheel cylinders (6RL, 6RR) can be pressurized by the master cylinder pressure.

  In the invention according to claim 7, the control means (100) controls the differential pressure by the first to fourth linear valves (SLFR, SLRL, SLFL, SLRR) when the power supply system fails, so that the left wheel The front wheel first and second wheel cylinders (6FR, 6FL) are set so that the total braking force generated at (FL, RL) and the total braking force generated at the right wheel (FR, RR) coincide or approximate. ) And the wheel cylinder pressure generated in the first and second wheel cylinders (6RL, 6RR) for the rear wheels.

  Thus, if the total braking force generated on the left wheels (FL, RL) and the total braking force generated on the right wheels (FR, RR) are brought close to each other, the yaw moment is brought close to zero. Therefore, the posture of the vehicle can be stabilized.

  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)
FIG. 1 shows a hydraulic circuit configuration of a vehicle brake control device to which an embodiment of the present invention is applied. FIG. 2 shows the input / output relationship of signals of the brake ECU 100 that controls the control system of the vehicle brake control device of this embodiment. Hereinafter, the configuration of the vehicle brake control device of the present embodiment will be described with reference to these drawings. Here, an example will be described in which the vehicle brake control device of the present embodiment is applied to a vehicle that constitutes a hydraulic circuit of an X pipe having the right front wheel-left rear wheel and the left front wheel-right rear wheel piping system.

  As shown in FIG. 1, in addition to the brake ECU 100 (see FIG. 2) described above, the vehicle brake control device includes a brake pedal 1, a pedal effort sensor 2, a master cylinder (hereinafter referred to as M / C) 3, a stroke. A control valve SCSS, a stroke simulator 4, a brake hydraulic pressure control actuator 5, W / C 6FR, 6FL, 6RL, 6RR are provided.

  When the driver depresses the brake pedal 1 corresponding to the brake operation member, the pedaling force applied to the brake pedal 1 is input to the pedaling force sensor 2 and a detection signal corresponding to the pedaling force applied from the pedaling force sensor 2 is output. It is configured. This detection signal is input to the brake ECU 100, and the pedal effort applied to the brake pedal 1 by the brake ECU 100 is detected. Here, the pedal force sensor 2 is exemplified as an operation amount sensor for detecting the operation amount of the brake operation member, but a stroke sensor or the like may be used. Moreover, you may enable it to detect the operation state of the brake pedal 1 by a driver based on the detection signal of a stroke sensor and the detection signal of the pressure sensors 17 and 18 for detecting the M / C pressure mentioned later.

  The brake pedal 1 is connected to a push rod or the like that transmits the applied pedal force to the M / C 3, and when the push rod or the like is pressed, the primary chamber 3 a and the secondary chamber 3 b provided in the M / C 3 are connected to the M. / C pressure is generated.

  The M / C 3 is provided with a primary piston 3c and a secondary piston 3d constituting the primary chamber 3a and the secondary chamber 3b, and these pistons receive the elastic force of the spring 3e so that each piston is not depressed. The brake pedal 1 is returned to the initial position side by pushing 3c and 3d.

  Pipe lines A and B extending from the primary chamber 3a and the secondary chamber 3b of the M / C 3 to the brake fluid pressure control actuator 5 are provided.

  The M / C 3 is provided with a master reservoir 3f. The master reservoir 3f is connected to each of the primary chamber 3a and the secondary chamber 3b through a passage (not shown) when the brake pedal 1 is in the initial position, and supplies brake fluid into the M / C 3 or M / Reserve surplus brake fluid in C3.

  A pipe C is directly extended from the master reservoir 3 f toward the brake fluid pressure control actuator 5.

  The stroke simulator 4 is connected to a pipeline D connected to the pipeline B, and plays a role of accommodating brake fluid in the secondary chamber 3b. The pipe D is provided with a stroke control valve SCSS constituted by a normally closed two-position valve capable of controlling the communication / blocking state of the pipe D, and the brake fluid to the stroke simulator 4 is provided by the stroke control valve SCSS. It is comprised so that the flow of can be controlled.

  The brake fluid pressure control actuator 5 is configured as follows.

  A pipe E connected to the pipe A is provided so as to connect the primary chamber 3a of the M / C 3 and the W / C (first W / C for front wheels) 6FR corresponding to the front wheel FR. The pipe E is provided with a first normally open valve SNO1. The first normally open valve SNO1 is a two-position valve that is in a communication state when not energized and is in a cutoff state when energized, and the communication / blocking state of the pipe E is controlled by the first normally open valve SNO1.

  Further, a pipe line F to which the pipe line B is connected is provided so as to connect the secondary chamber 3b of the M / C 3 and the W / C (front wheel second W / C) 6FL corresponding to the front wheel FL. The pipe F is provided with a second normally open valve SNO2. The second normally open valve SNO2 is a two-position valve that is in a communication state when not energized, and is in a cutoff state when energized, and the communication / blocking state of the pipe F is controlled by the second normally open valve SNO2.

  Further, a pipe line G to which a pipe line C extending from the master reservoir 3f is connected is provided. This pipeline G branches into four pipelines G1, G2, G3, and G4, and corresponds to W / C6FR and 6FL corresponding to the above-described front wheels FR and FL, and rear wheels RL and RR. W / C (first and second W / C for rear wheels) 6RL, 6RR.

  Each of the pipelines G1 to G4 is provided with one pump (first to fourth pump) 7, 8, 9, and 10, respectively. Each pump 7-10 is comprised, for example by the trochoid pump effective for silence. Among the pumps 7 to 10, the pumps 7 and 8 are driven by the first motor 11, and the pumps 9 and 10 are driven by the second motor 12. Although any motor may be used as the first and second motors 11 and 12, it is preferable to use a brushless motor that rises quickly.

  In addition, each of the pumps 7 to 10 is provided with pipe lines H1, H2, H3, and H4 that constitute a pressure regulating circuit in parallel.

  The pipe H1 connected in parallel to the pump 7 is provided with a first normally closed valve SWC1 and a first linear valve SLFR connected in series, and the first normally closed valve SWC1 is inhaled by the pump 7. The first linear valve SLFR is arranged on the port side (upstream side) so as to be located on the discharge port side (downstream side). That is, the first normally closed valve SWC1 can control the return of the brake fluid to the master reservoir 3f side through the pipe H1.

  A pipe H2 connected in parallel to the pump 8 is provided with a second linear valve SLRL.

  The pipe H3 connected in parallel to the pump 9 is provided with a second normally closed valve SWC2 and a third linear valve SLFL connected in series, and the second normally closed valve SWC2 is inhaled by the pump 9. The third linear valve SLFL is arranged on the port side (upstream side) so as to be located on the discharge port side (downstream side). That is, the second normally closed valve SWC2 can control the return of the brake fluid to the master reservoir 3f side through the pipe H3.

  A pipe H4 connected in parallel to the pump 10 is provided with a fourth linear valve SLRR.

  And among the pipe lines G1-G4, pressure sensors (first to fourth pressure sensors) 13, 14, 15, 16 are disposed between the pumps 7-10 and the W / C 6FR-6RR, Each W / C pressure is configured to be detected, and the pressure sensor 17 is also provided upstream of the first and second normally open valves SNO1 and SNO2 (M / C3 side) of the pipes E and F. By arranging 18, the M / C pressure generated in the primary chamber 3 a and the secondary chamber 3 b of the M / C 3 can be detected.

  Further, the discharge port of the pump 7 for pressurizing the W / C6FR for the front wheel FR and the discharge port of the pump 9 for pressurizing the W / C6FL for the front wheel FL are provided with check valves 20 and 21, respectively. Yes. These check valves 20 and 21 are provided to prohibit the flow of brake fluid from the W / C 6FR, 6FL side to the pumps 7, 9 side. With such a structure, the brake fluid pressure control actuator 5 is configured.

  In such a vehicle brake control device, a hydraulic circuit (first auxiliary pipeline) connecting the primary chamber 3a and the W / C 6FR through the pipeline A and pipeline E described above, a pipeline C, pipelines G and G1, Hydraulic circuit (main pipeline) connecting master reservoir 3f and W / C 6FR, 6RL through G2, and hydraulic circuits (first and second regulating circuits) of pipelines H1, H2 connected in parallel to pumps 7, 8 ) Constitutes the first piping system.

  Also, a hydraulic circuit (second auxiliary pipeline) connecting the secondary chamber 3b and the W / C 6FR through the pipeline B and the pipeline F, and the master reservoir 3f and the W / C 6FL through the pipeline C, the pipelines G, G3, and G4, The hydraulic circuit (main pipeline) connecting 6RR and the hydraulic circuits (third and fourth pressure regulating circuits) of the pipelines H3 and H4 connected in parallel to the pumps 9 and 10 constitute the second piping system. It becomes.

  Then, as shown in FIG. 2, detection signals from the pedal force sensor 2 and the pressure sensors 13 to 18 are input to the brake ECU 100.

  The brake ECU 100 is configured by a known microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and executes various processes according to a program stored in the ROM. The brake ECU 100 includes, for example, various control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR, ON / OFF of the power supply line to the first and second motors 11 and 12, or this line Is provided with a semiconductor switching element (not shown) for controlling the value of the current flowing through the power supply. By controlling ON / OFF of the semiconductor switching element, the power supply is turned ON / OFF and the amount of current supplied (that is, consumption) The amount of power) can be controlled.

  For example, the brake ECU 100 obtains a physical value of the pedal effort corresponding to the brake operation amount from the input detection signal of the pedal effort sensor 2, obtains a target braking force corresponding thereto, and generates various target braking forces. Control signals for driving the control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and the first and second motors 11 and 12 are output. Then, the brake ECU 100 obtains the W / C pressure and the M / C pressure from the detection signals of the pressure sensors 13 to 18 to feed back the braking force (actual braking force) that is actually generated, thereby achieving target control. Try to get close to power.

  The output of control signals for driving the brake ECU 100 and the various control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and the first and second motors 11 and 12 shown in FIG. As shown in FIG. 4, the process is basically performed based on the power supply from the on-vehicle battery 20. However, when the power supply system fails, power cannot be supplied from the battery 20, so that power is supplied from the capacitor 21 that functions as an auxiliary battery.

  The capacitor 21 is mounted on a vehicle in which a brake control device of a brake-by-wire system is generally mounted, and is charged by power supply from the battery 20. Similarly to the battery 20, the capacitor 21 is connected to the brake ECU 100, and supplies power to the brake ECU 100 in place of the battery 20 when the potential generated by the battery 20 is 0 or below a predetermined value. Then, power is supplied to the various control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and the first and second motors 11 and 12 through the brake ECU 100.

  Next, the operation of the vehicle brake control device configured as described above will be described separately when normal braking occurs, when an abnormality occurs in the vehicle brake control device (hereinafter referred to as abnormal), and when the power supply system fails. To do. The term “abnormality” here means an abnormality different from the power supply system failure, for example, one of the control valves has failed.

  FIG. 3 is a schematic diagram showing the driving state of each part at the time of normal braking, abnormality, and power system failure. Whether or not an abnormality has occurred is determined by the brake ECU 100 based on a conventional initial check or the like, and once an abnormality occurs, the brake operation at the time of the abnormality is performed until the abnormality is canceled. It will be.

(1) Operation During Normal Brake During normal braking, when the brake pedal 1 is depressed and a detection signal from the pedal force sensor 2 is input to the brake ECU 100, various types of driving are performed so that the brake ECU 100 has a drive configuration as shown in FIG. The control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and the first and second motors 11 and 12 are driven.

  That is, the energization of the first and second normally open valves SNO1 and SNO2 is both turned on, and the energization of the first and second normally closed valves SWC1 and SWC2 are both turned on. As a result, the first and second normally open valves SNO1, SNO2 are both shut off, and the first, second normally closed valves SWC1, SWC2 are both in communication.

  In addition, the first to fourth linear valves SLFR, SLRL, SLFL, and SLRR are configured so that the energization amount per unit time is adjusted by duty control (or PWM control) of energization ON / OFF, and between upstream and downstream The amount of differential pressure to be generated is controlled linearly. The stroke control valve SCSS is energized. For this reason, even if each piston 3c, 3d moves when the stroke simulator 4 will be in communication with the secondary chamber 3b through the pipes B and D and the brake pedal 1 is depressed, the brake fluid in the secondary chamber 3b Will move to the stroke simulator 4. Therefore, when the driver depresses the brake pedal 1, a reaction force corresponding to the depressing is obtained, and a feeling that the hard pedal is depressed with respect to the brake pedal 1 because the M / C pressure becomes excessively high (the plate) The brake pedal 1 can be stepped on without feeling.

  Further, energization of the first and second motors 11 and 12 is both turned ON, and the brake fluid is sucked and discharged by the pumps 7 to 10. Thus, when the pump operation by the pumps 7 to 10 is performed, the brake fluid is supplied to the respective W / C 6FR to 6RR.

  At this time, since the first and second normally open valves SNO1, SNO2 are shut off, the brake fluid pressure downstream of the pumps 7-10, that is, the W / C pressure of each W / C6FR-6RR is increased. Will be. Since the first and second normally closed valves SWC1 and SWC2 are in communication, the energization amount per unit time to the first to fourth linear valves SLFR, SLRL, SLFL and SLRR is duty-controlled. The W / C pressure of each W / C 6FR to 6RR is adjusted according to the duty ratio.

  The brake ECU 100 monitors the W / C pressure generated in the W / C 6 FR to 6 RR of the wheels FR to RR based on the detection signals of the pressure sensors 13 to 16, and the first and second motors 11. , 12 to control the rotational speed of the first and second motors 11, 12, and ON / OFF duty of energization to the first to fourth linear valves SLFR, SLRL, SLFL, SLRR By controlling the ratio, each W / C pressure is set to a desired value.

  As a result, the braking force is generated so that the target braking force corresponding to the pedaling force applied to the brake pedal 1 is obtained.

(2) Brake operation at the time of abnormality When an abnormality occurs, a control signal cannot be output from the brake ECU 100, or the control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and the first and second control valves The motors 11 and 12 may not be driven normally. For this reason, as shown in FIG. 3, the energization is turned off for all the control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and all of the first and second motors 11 and 12.

  That is, since the energization to both the first and second normally open valves SNO1, SNO2 is turned off, both are in a communication state. Since the energization of the first and second normally closed valves SWC1 and SWC2 is also turned off, both are cut off.

  In addition, all of the first to fourth linear valves SLFR, SLRL, SLFL, and SLRR are in the communication state because the energization is turned off. Since the energization of the stroke control valve SCSS is also turned off, the stroke simulator 4 and the secondary chamber 3b are disconnected.

  Further, the energization of the first and second motors 11 and 12 is both turned OFF, and the brake fluid suction and discharge by the pumps 7 to 10 are also stopped.

  In this state, the primary chamber 3a in the M / C 3 is connected to the W / C 6FR in the right front wheel FR via the pipelines A, E, and G1, and the secondary chamber 3b is connected to the pipelines B, F, It is connected to W / C6FL in the left front wheel FL through G3.

  For this reason, when the brake pedal 1 is depressed and a push rod or the like is pushed according to the applied pedaling force to generate M / C pressure in the primary chamber 3a and the secondary chamber 3b in the M / C 3, It is transmitted to W / C6FR and 6FL of both front wheels FR and FL. As a result, a braking force is generated for both front wheels FR and FL.

  In such an abnormal operation, the W / C pressures of the W / C 6FR and 6FL on the front wheel side are generated in the pipelines G1 and G3, but the check valves 20 and 21 are provided. When the W / C pressure is applied to the pumps 7 and 9, it is possible to prevent the brake fluid from leaking in the pumps 7 and 9 and reducing the W / C pressure.

(3) Operation when the power supply system fails The operation when the power supply system fails is when the brake ECU 100 determines that the power supply from the battery 20 is no longer performed or that the power supply is insufficient. Executed. This determination is generally performed in the brake ECU 100 and is performed, for example, by monitoring the voltage applied from the battery 20 by the brake ECU 100. Since this determination is a well-known matter, details are omitted.

  When the power supply system fails, basically, one pipe system performs the same operation as during normal braking, but the other pipe system performs the same operation as during an abnormality. In the brake-by-wire type vehicle brake control device, the first and second motors 11 and 12 have the largest power consumption. Therefore, the power consumption can be reduced by making the method of energizing them different from that during normal braking. It is for illustration.

  Specifically, as shown in FIG. 3, when the brake pedal 1 is depressed, the drive modes of the various control valves SNO2, SWC2, SLFL, SLRR are the same as those during normal braking, and the various control valves SCSS, The drive modes of SNO1, SWC1, SLFR, and SLRL are the same as in the abnormal state. As for the first and second motors 11 and 12, the first motor 11 is OFF and the second motor 12 is ON. At this time, the stroke control valve SCSS is turned OFF.

  Therefore, the second piping system performs the same operation as during normal braking, and the W / C 6FL and 6RR corresponding to the left front wheel FL and the right rear wheel RR are pumped by driving the second motor 12. The W / C pressure is generated by the brake fluid pressure discharged from 9,10. Further, the first piping system performs the same operation as that at the time of abnormality, and the first motor 11 is not driven for the W / C 6FR and 6RL corresponding to the right front wheel FR and the left rear wheel RL. The W / C pressure is generated only in W / C6FR by the M / C pressure generated in C3.

  In this way, it is possible to generate a braking force even when the power supply system fails, and it is possible to generate a braking force equivalent to that during normal braking by driving the second motor 12 for one piping system. Therefore, it is possible to generate as much braking force as possible while reducing the power consumption compared to the normal braking.

  At this time, for the W / C 6FL, 6RR corresponding to the left front wheel FL and the right rear wheel RR, the total braking force generated in the left two wheels FL, RL and the total generated in the right two wheels FR, RR. It is preferable to adjust the W / C pressure by using a pressure adjusting circuit so that the braking forces of the two are equal.

  That is, as described above, by driving the second motor 12 for the second piping system, a braking force equivalent to that during normal braking is generated, and for the first piping system, an abnormality based on the pedaling force on the brake pedal 1 is generated. The braking force equivalent to the time is generated. For this reason, if the W / C pressure to be generated for the W / C 6FL and 6RR corresponding to the left front wheel FL and the right rear wheel RR in the second piping system is the same as that during normal braking, the left two wheels FL, The total braking force generated in the RL and the total braking force generated in the right two wheels FR and RR do not match.

  FIG. 4 shows the relationship between the braking forces generated in the wheels FL to RR in this case. In the figure, the size of the arrow represents the magnitude of the braking force, and since the braking force generated on the left and right sides of the vehicle is unbalanced, a yaw moment is generated, which is not desirable for stabilizing the posture of the vehicle. .

  Accordingly, if the W / C pressure to be generated is adjusted with respect to the W / C 6FL and 6RR corresponding to the left front wheel FL and the right rear wheel RR in the second piping system, the total generated in the left two wheels FL and RL. And the total braking force generated in the right two wheels FR and RR can be made equal.

  FIG. 5 shows the relationship between the braking forces generated in the wheels FL to RR in this case. In the figure, the size of the arrow represents the magnitude of the braking force, and since the braking force generated on the left and right sides of the vehicle can be balanced, the yaw moment can be brought close to 0 and the vehicle posture can be stabilized. It becomes possible.

  As described above, in the vehicle brake control device of the present embodiment, the motor is driven only to one of the piping systems when the power supply system fails. For this reason, even when the power supply system fails, the braking force can be generated by increasing the W / C pressure using the motor. Therefore, as much braking force as possible while reducing power consumption compared to normal braking. Can be generated.

  Moreover, about the other piping system, the braking force equivalent to the time of abnormality based on the depressing force to the brake pedal 1 is generated. For this reason, it becomes possible to generate a larger braking force than when no braking force is generated for the other piping system.

(Second Embodiment)
A second embodiment of the present invention will be described. In the first embodiment, the second piping system is driven by the second motor 12 to generate a braking force equivalent to that during normal braking, and the first piping system is abnormal due to the pedaling force on the brake pedal 1. The braking force equivalent to the time is generated. For this reason, regarding the first piping system, the W / C pressure is generated only at the W / C 6 FR corresponding to the right front wheel FR. In contrast, in the present embodiment, the W / C pressure is also generated in the W / C 6RL corresponding to the left rear wheel RL.

  At the time of abnormality, it is not known in which part of the brake fluid pressure control actuator 5 the abnormality has occurred, so the various control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR and the first and second Assuming that the motors 11 and 12 may not be driven normally, they are not driven at all.

  However, no abnormality has occurred in the brake fluid pressure control actuator 5 when the power supply system fails, so even if the various control valves SCSS, SNO1, SNO2, SWC1, SWC2, SLFR, SLRL, SLFL, SLRR are driven. I do not care.

  For this reason, the M / C pressure generated in the primary chamber 3a by driving the first normally closed valve SWC1 with respect to the drive mode at the time of the power supply system failure described in the first embodiment is the W of the first piping system. / C6FR, 6RL may not be transmitted. In this case, the W / C pressure can be increased by pump pressurization by driving the second motor 12 only for the W / C 6FL and 6RR of the second piping system.

  In the case of the present embodiment, braking force is generated only for the left front wheel FL and the right rear wheel RR. However, in general, in a vehicle, the front wheels FR and FL are set to generate a higher braking force than the rear wheels RL and RR, so that the same W / C pressure is generated in the W / C 6FL and 6RL. In this case, as described in the first embodiment, the braking force generated on the left front wheel FL and the right rear wheel RR becomes unbalanced, and a yaw moment is generated. For this reason, the third and fourth linear valves SLFL, SLRR are set so that the pressure of W / C6RR is higher than that of W / C6FL so that the braking forces generated on the left front wheel FL and the right rear wheel RR are balanced. It is preferable to perform pressure regulation at

(Third embodiment)
A third embodiment of the present invention will be described. In the first embodiment, only the W / C6FR on the front wheel side is pressurized by the M / C pressure, but both the W / C6FR and 6RL on the front wheel side and the rear wheel side are pressurized by the M / C pressure. You may make it press. However, in this case, a hydraulic circuit different from that in the first embodiment is used. FIG. 6 shows a hydraulic circuit configuration of the vehicle brake control device used in the present embodiment.

  As shown in this figure, in the vehicle brake control device of the present embodiment, the pipeline G is branched into two pipelines Ga and Gb, and the pipeline Ga (that is, downstream of the branch point and the pipeline) A first normally closed valve SWC1 is provided on the upstream side of H1 and H2, and a second normally closed valve SWC2 is provided on the pipeline Gb (that is, downstream of the branch point and upstream of the pipelines H3 and H4). As a configuration.

  According to such a configuration, even when the first normally closed valve SWC1 is shut off at the time of an abnormality, only the upstream side of the pipelines H1 and H2 is shut off. When the M / C pressure is generated in the primary chamber 3a, it can be transmitted not only to the W / C6FR of the right front wheel FR but also to the W / C6RL of the left rear wheel RL. Similarly, even if the second normally closed valve SWC2 is shut off in the event of an abnormality, the upstream side of the pipelines H3 and H4 is only shut off, so that the brake pedal 1 is depressed to enter the secondary chamber 3b of the M / C3. When the M / C pressure is generated, it can be transmitted not only to W / C6FL of the left front wheel FL but also to W / C6RR of the right rear wheel RR.

  In such a piping configuration, when the power supply system fails, both the W / C 6FR and 6RL are pressurized by the M / C pressure for the first piping system in which the W / C pressure is not pressurized by the pump pressurization. It becomes possible. As a result, the braking force can be generated for all four wheels, so that a more balanced braking force can be generated. However, in this embodiment, the total braking force generated on the left two wheels FL and RL and the total braking force generated on the right two wheels FR and RR are also different so that a more balanced braking force is generated. It is preferable to adjust the W / C pressure using a pressure adjusting circuit so as to be equivalent.

  In this embodiment, the check valves 20 and 21 shown in the first embodiment are not provided, but even if brake fluid leaks from the pumps 7 and 9, the check valves 20 and 21 are positioned upstream of the pumps 7 and 9. Since the brake fluid is stopped by the first and second normally closed valves SWC1 and SWC2, the W / C pressure does not decrease.

(Other embodiments)
In each of the above-described embodiments, the case where the power supply system has failed has been described as an example. However, in addition to the case where the power supply system has failed, when the failed part can be identified, for example, when only the first motor 11 is malfunctioning. In addition, it is possible to obtain the same effect as described above by driving the motor only to one piping system as described above.

  The vehicle brake control device shown in FIG. 1 is shown as an example of a brake configuration to which the present invention can be applied, and is not limited to that shown in FIG. 1 and can be modified in various forms.

  Moreover, in each said embodiment, the example which applied the brake control apparatus for vehicles of this embodiment to the vehicle which comprises the hydraulic circuit of X piping provided with each piping system of a right front wheel-left rear wheel and a left front wheel-right rear wheel. However, the present invention is also applicable to other systems such as front and rear piping.

  Further, in each of the above embodiments, by driving the second motor 12 when the power supply system fails, the W / C pressure is pumped for the second piping system, and the W / C pressure is applied for the first piping system. It demonstrated as a form pressurized based on the M / C pressure generate | occur | produced by operation of the brake pedal 1. FIG. However, this is just an example, and the W / C pressure is pumped with respect to the first piping system and the W / C pressure is generated by the operation of the brake pedal 1 with respect to the second piping system. It is possible to adopt a form in which the pressure is applied based on

  In each of the above embodiments, the first and second normally closed valves SWC1 and SWC2 are normally closed, but may be normally open control valves. Although the first and second normally open valves SNO1 and SNO2 are also normally open, these may be normally closed control valves.

  In addition, although the brake pedal 1 was mentioned as an example as a brake operation member, a brake lever etc. may be sufficient.

It is a figure which shows the hydraulic circuit structure of the brake control apparatus for vehicles in 1st Embodiment of this invention. It is a block diagram which shows the input / output relationship of the signal of brake ECU which manages the control system of the brake control apparatus for vehicles shown in FIG. It is the model which showed the drive state of each part at the time of normal braking, at the time of abnormality, and a power supply system failure. The relationship between the braking force generated on each wheel FL to RR when the total braking force generated on the left two wheels FL and RL and the total braking force generated on the right two wheels FR and RR do not coincide is shown. FIG. The relationship between the braking force generated on each wheel FL to RR when the total braking force generated on the left two wheels FL and RL and the total braking force generated on the right two wheels FR and RR are matched is shown. FIG. It is a figure which shows the hydraulic circuit structure of the brake control apparatus for vehicles in 3rd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Brake pedal, 2 ... Treading force sensor, 3 ... M / C, 3a ... Primary chamber, 3b ... Secondary chamber, 3c ... Primary piston, 3d ... Secondary piston, 3e ... Spring, 3f ... Master reservoir, 4 ... Stroke simulator, 5 ... Actuator for brake fluid pressure control, 6FR, 6FL, 6RL, 6RR ... W / C, 7-10 ... Pump, 11, 12 ... Motor, 13-18 ... Pressure sensor, 20, 21 ... Check valve, 100 ... Brake ECU, A, B, C, D, E, F, G1 to G4, H1 to H4 ... Pipe line, FR, FL, RL, RR ... Wheel, SCSS ... Stroke control valve, SLFL, SLFR, SLRR, SLRR ... 1st-4th linear valve, SNO1, SNO2 ... 1st, 2nd normally open valve, SWC ... Normally closed valve, SWC1, SWC2 ... 1st, 2nd normally closed valve.

Claims (7)

A brake operating member (1) operated by a driver;
A brake operation amount sensor (2) for detecting an operation amount of the brake operation member (1);
Front wheel first and second wheel cylinders (6FR, 6FL) provided corresponding to each of the two front wheels (FR, FL), and two rear wheels (RL, RR) provided respectively. Rear wheel first and second wheel cylinders (6RL, 6RR);
A reservoir (3f) storing brake fluid;
The reservoir (3f) is connected to the front wheel first, second and rear wheel first, second wheel cylinders (6FR to 6RR), the front wheel first, second and rear wheel first, Main pipes (C, G, G1 to G4) branched into four so as to be connected to the second wheel cylinders (6FR to 6RR),
One is arranged for each of the four branches (G1 to G4) of the main pipelines (C, G, G1 to G4), and the brake fluid stored in the reservoir (3f) The first pump (7) that discharges and pressurizes the front wheel first wheel cylinder (6FR), the second pump (8) that pressurizes the rear wheel first wheel cylinder (6RL), and the front wheel second A third pump (9) for pressurizing the wheel cylinder (6FL) and a fourth pump (10) for pressurizing the second wheel cylinder (6RR) for the rear wheel;
To drive the first and second pumps (7, 8) provided in the first piping system using the system pressurized by the first and second pumps (7, 8) as a first piping system. A first motor (11) of
To drive the third and fourth pumps (9, 10) provided in the second piping system using the system pressurized by the third and fourth pumps (9, 10) as the second piping system. A second motor (12) of
First to fourth pressure regulating circuits (H1 to H4) arranged in parallel to the first to fourth pumps (7 to 10) and serving as conduits for returning the brake fluid to the reservoir (3f);
First to fourth linear valves (SLFR, SLRL, SLFL, SLRR) arranged corresponding to the first to fourth pressure regulating circuits (H1 to H4), respectively;
Control for driving the first to fourth linear valves (SLFR, SLRL, SLFL, SLRR) and the first and second motors (11, 12) based on a detection signal of the brake operation amount sensor (2). Means (100);
A battery (20) for supplying power for driving the control means (100), the pressure regulating means (SLFR, SLRL, SLFL, SLRR) and the motors (11, 12);
A capacitor (21) serving as an auxiliary power source when power cannot be supplied from the battery (20),
The control means (100)
When it is detected that the brake operation member (1) is operated based on the operation amount sensor (2), a target braking force corresponding to the operation amount obtained by the operation amount sensor (2) is obtained, Based on the power supply from the battery (20) or the capacitor (21) to generate the target braking force, the first and second motors (11, 12) and the pressure regulating means (SLFR, SLRL, SLFL, SLRR),
Further, when the power supply system fails to supply power from the battery (20), only one of the first and second piping systems is related to the power supply of the capacitor (21). A vehicle brake control device that pressurizes a wheel cylinder pressure by pressurizing a pump by discharging brake fluid from the first and second motors (11, 12). The primary piston (3c) and the secondary piston (3d), the primary chamber (3a) and the secondary chamber (3b) partitioned by these, brake fluid communicating with the primary chamber (3a) and the secondary chamber (3b) A master reservoir (3f) corresponding to the stored reservoir is provided, and when the brake operation member (1) is operated, the primary piston (via the push rod connected to the brake operation member (1)). 3c) and a master cylinder (3) configured to generate a master cylinder pressure for the primary chamber (3a) and the secondary chamber (3b) by pressing the secondary piston (3d);
A first auxiliary pipe (A, E) connecting the primary chamber (3a) to the front wheel first wheel cylinder (6FR) on the downstream side of the front wheel first pump (7);
A first control valve (SNO1) that is provided in the first auxiliary pipeline (A, E) and controls communication / blocking of the first auxiliary pipeline (A, E);
A second auxiliary pipe (B, F) connecting the secondary chamber (3b) to the front wheel second wheel cylinder (6FL) on the downstream side of the front wheel second pump (9);
A second control valve (SNO2) that is provided in the second auxiliary pipeline (B, F) and that controls communication / blocking of the second auxiliary pipeline (B, F);
The control means (100)
Of the first and second piping systems, the first and second piping systems that pressurize the wheel cylinder pressure by pump pressurization by the discharge of brake fluid from the first and second motors (11, 12). The control valves (SNO1, SNO2) are shut off,
With respect to the piping system that does not pressurize the wheel cylinder pressure by the pump pressurization, the first and second control valves (SNO1, SNO2) are in a communicating state, and the first, Regarding the piping system for pressurizing the wheel cylinder pressure by pump pressurization by the discharge of the brake fluid of the second motor (11, 12), the first auxiliary pipeline (A, E) or the second auxiliary pipeline ( 2. The vehicle brake according to claim 1, wherein the wheel cylinder pressure is increased by the master cylinder pressure generated based on the operation of the brake operation member (1) through B, F). 3. Control device. The control means (100) is a pipe that does not pressurize the wheel cylinder pressure by pump pressurization by discharge of brake fluid of the first and second motors (11, 12) of the first and second pipe systems. The vehicle brake control device according to claim 2, wherein only the front wheel cylinders (6FR, 6FL) are pressurized by the master cylinder pressure. The first pressure regulating pipe (H1) is provided with a third control valve (SWC1) for controlling communication / blocking between the first linear valve (SLFR) and the master reservoir (3f),
The third pressure regulating pipe (H3) is provided with a fourth control valve (SWC2) for controlling communication / blocking between the third linear valve (SLFL) and the master reservoir (3f),
The control means (100) is a piping system that pressurizes a wheel cylinder pressure by pump pressurization by discharge of brake fluid of the first and second motors (11, 12) of the first and second piping systems. With respect to the piping system on which the third and fourth control valves (SWC1, SWC2) are in communication and the wheel cylinder pressure is not increased by pressurizing the pump, the third and fourth control valves (SWC1, SWC2) are connected. The vehicle brake control device according to claim 3, wherein: The control means (100) is a pipe that does not pressurize the wheel cylinder pressure by pump pressurization by discharge of brake fluid of the first and second motors (11, 12) of the first and second pipe systems. 3. The vehicle brake control according to claim 2, wherein both the front wheel cylinder (6FR, 6FL) and the rear wheel cylinder (6RL, 6RR) are pressurized by the master cylinder pressure. apparatus. Among the main pipelines (C, G, G1 to G4), the master reservoir (3f) and the first piping are upstream of the connection point with the first to fourth pressure regulating circuits (H1 to H4). The master reservoir (3f) is provided with a third control valve (SWC1) for controlling communication / blocking between the first front wheel wheel cylinder and the first rear wheel wheel cylinder (6FR, 6RL) in the system. And a third control valve (SWC2) for controlling communication / blocking between the second front wheel wheel cylinder and the second rear wheel wheel cylinder (6FL, 6RR) in the second piping system,
The control means (100) is a piping system that pressurizes a wheel cylinder pressure by pump pressurization by discharge of brake fluid of the first and second motors (11, 12) of the first and second piping systems. With respect to the piping system on which the third and fourth control valves (SWC1, SWC2) are in communication and the wheel cylinder pressure is not increased by pressurizing the pump, the third and fourth control valves (SWC1, SWC2) are connected. 6. The vehicle brake control device according to claim 5, wherein: The control means (100) generates the left wheel (FL, RL) by controlling the differential pressure by the first to fourth linear valves (SLFR, SLRL, SLFL, SLRR) when the power supply system fails. The front wheel first and second wheel cylinders (6FR, 6FL) and the rear wheel first so that the total braking force generated and the total braking force generated on the right wheels (FR, RR) coincide or approximate. The vehicle brake control device according to any one of claims 1 to 6, wherein the wheel cylinder pressure generated in the first and second wheel cylinders (6RL, 6RR) is regulated.

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