JP5438563B2 - Brake control device - Google Patents

Description

  The present invention relates to a brake control device that applies braking force to wheels.

  2. Description of the Related Art Conventionally, there has been known a brake device that applies a braking force by generating a hydraulic pressure in a hydraulic circuit according to an operation amount of a brake pedal and supplying the hydraulic pressure to a wheel cylinder of each wheel. Each actuator of the brake device is driven and controlled by outputting a control command to the actuator drive circuit by an electronic control device (hereinafter referred to as “ECU”) mounted on the vehicle.

  In Patent Document 1, in order to individually detect the disconnection abnormality of a plurality of relays, only one of the plurality of relays is turned on and the rest are turned off in order with respect to the plurality of relays. In addition, it is disclosed that when each relay is turned on independently, it is determined whether or not a voltage is applied to the motor through a voltage detection resistor to detect disconnection abnormality of each relay.

JP 2005-324781 A

  Incidentally, a motor that drives a pump that supplies hydraulic pressure to a wheel cylinder is normally controlled by an ECU, but when a predetermined condition is satisfied, it is driven by a motor drive circuit that is different from a normal motor drive circuit. The It is necessary to check whether the motor drive circuit operates when a predetermined condition is satisfied.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a brake control device that can check the operating state of a motor drive circuit before an abnormality occurs in an ECU.

In order to solve the above problems, a brake control device according to an aspect of the present invention includes a control unit that controls a motor that drives a pump, and a plurality of motor drive circuits that drive the motor when the control unit is abnormal. When a motor drive signal is output and a plurality of motor drive circuits arranged in parallel and a signal indicating an abnormality of the control means are received, one of the drive signals of the plurality of motor drive circuits An arbitration circuit that selects and outputs one drive signal and supplies the drive signal to the motor. The control means outputs a signal indicating an abnormality of the control means in order to check the operation state of the plurality of motor drive circuits when the control means is normal in the process of checking the operation states of the plurality of motor drive circuits , The operating state of the motor drive circuit is checked based on the output of the motor drive circuit received from the arbitration circuit.

  According to this aspect, it becomes possible to check the operating state of the motor drive circuit that drives the motor instead of the control means when the control means is abnormal before the control means becomes abnormal.

  The first motor drive circuit among the plurality of motor drive circuits may output a motor drive signal when a signal indicating abnormality of the control means is input. By outputting a signal indicating an abnormality of the control means, it is possible to check the operating state with respect to the first motor drive circuit that starts operation when a signal indicating an abnormality of the control means is input.

  The control means may output a signal indicating an abnormality of the control means when the ignition switch is turned on from off. Thereby, the operating state of the first motor drive circuit can be checked immediately after the start of operation.

  According to the present invention, in the brake control device, the operating state of the motor drive circuit can be inspected before an abnormality occurs in the ECU.

It is a systematic diagram which shows the brake control apparatus which concerns on embodiment centering on the hydraulic circuit. It is a figure which shows the function structure of brake ECU which concerns on embodiment. It is a flowchart which shows the process which checks the operating state of the motor drive circuit which concerns on embodiment.

  In the embodiment, the brake control device includes a plurality of motor drive circuits that output a drive signal of the motor, an arbitration circuit that can supply any one of the outputs of the plurality of motor drive circuits to the motor, and the plurality of motors. Control means for checking the operating state of the drive circuit is provided. This control means includes a CPU (Central Processing Unit) of the ECU and an input / output circuit. The brake control device configures a plurality of motor drive circuits so that the motor operates even if the CPU should fail. For example, the first motor drive circuit among the plurality of motor drive circuits outputs a motor drive signal and operates the motor when receiving a signal indicating abnormality of the control means. It is necessary to check whether the plurality of motor drive circuits operate normally when the CPU fails. Furthermore, it is necessary to check the arbitration circuit that supplies the output of the motor drive circuit to the motor.

  Therefore, the control means outputs a signal indicating the abnormality of the control means itself, and checks the operating state of the motor drive circuit based on the output of the motor drive circuit received from the arbitration circuit. This makes it possible to check the operating state of the motor drive circuit before an abnormality occurs in the control means.

  FIG. 1 is a system diagram showing a brake control device according to an embodiment centered on a hydraulic circuit thereof. The brake control device 610 employs an electronically controlled brake system (ECB), and independently and optimally sets the four-wheel brakes of the vehicle according to the operation of the brake pedal 12 as a brake operation member by the driver.

  The brake pedal 12 is connected to a master cylinder 14 that sends out brake oil as hydraulic fluid in response to a depression operation by the driver. Further, the brake pedal 12 is provided with a stroke sensor 22 that detects the depression stroke and a stop lamp switch (not shown) that detects whether or not the brake pedal 12 is depressed. A reservoir tank 24 is connected to the master cylinder 14, and a stroke simulator that creates a reaction force corresponding to the operating force of the brake pedal 12 by the driver via an on-off valve 26 at one output port of the master cylinder 14. 25 is connected. The on-off valve 26 is a so-called normally-closed linear valve that closes when no current is supplied, and is supplied with current when the driver depresses the brake pedal 12 and is opened.

  A pipe line A for the right front wheel is connected to one output port of the master cylinder 14. The pipe A is connected to the pipe F, and the pipe F is connected to a right front wheel wheel cylinder 20FR that applies a braking force to the right front wheel. Further, a pipe B for the left front wheel is connected to the other output port of the master cylinder 14. The pipeline B is connected to the pipeline G, and the pipeline G is connected to a left front wheel wheel cylinder 20FL that applies a braking force to the left front wheel.

  A shutoff valve 28 is provided in the middle of the pipeline F, and a shutoff valve 30 is provided in the middle of the pipeline G. The shut-off valve 28 and the shut-off valve 30 are both so-called normally-open linear valves, which are closed in a state where current is supplied, and the master cylinder 14 and the right front wheel wheel cylinder 20FR or the left front wheel wheel cylinder 20FL are closed. The master cylinder 14 and the right front wheel wheel cylinder 20FR or the left front wheel wheel cylinder 20FL are communicated with each other by preventing the communication with the valve and opening the valve when the current supply is reduced or stopped.

  Further, in the middle of the pipeline F, a hydraulic pressure sensor 70 for detecting the master cylinder pressure on the right front wheel side is provided. A fluid pressure sensor 72 for detecting the master cylinder pressure on the left front wheel side is provided in the middle of the pipe line G for the left front wheel. In the brake control device 610, when the brake pedal 12 is depressed by the driver, the depression operation amount is detected by the stroke sensor 22, but also from the master cylinder pressure detected by the hydraulic pressure sensor 70 and the hydraulic pressure sensor 72. The depressing operation force (depressing force) of the brake pedal 12 can be obtained.

  A suction port of a pump 634 driven by a motor 632 is connected to the other end of the pipe C connected at one end to the reservoir tank 24. The discharge port of the pump 634 is connected to a high-pressure line H6 that forms a high-pressure passage, and an accumulator 650 and a relief valve 653 are connected to the high-pressure line H6. The accumulator 650, the pump 634, and the motor 632 constitute a power hydraulic pressure source capable of accumulating brake fluid hydraulic pressure. When the pump 634 is not driven, communication with the high-pressure line H6 is substantially blocked. In the embodiment, a gear pump that is rotationally driven by a motor 632 is employed as the pump 634. A motor with a brush is used as the motor 632. Further, as the accumulator 650, an accumulator 650 that converts the pressure energy of the brake fluid into the pressure energy of an enclosed gas such as nitrogen is stored.

  The accumulator 650 normally stores brake fluid whose internal hydraulic pressure (hereinafter referred to as “accumulator pressure”) is increased to a predetermined setting range (for example, about 8 to 12 MPa) by the pump 634. The valve outlet of the relief valve 653 is connected to the high-pressure line H6. When the hydraulic pressure in the high-pressure line H6 increases abnormally to about 25 MPa, for example, the relief valve 653 is opened, and the high-pressure brake fluid is It is returned to the reservoir tank 24 via the high-pressure line H6. Further, an accumulator pressure sensor 651 for detecting the hydraulic pressure of the internal working fluid (equal to the accumulator pressure in the embodiment) is provided in the high-pressure line H6.

  The high-pressure line H6 is connected to the right front wheel wheel cylinder 20FR, the left front wheel wheel cylinder 20FL, the right rear wheel wheel cylinder 20RR and the left rear wheel via the pressure increasing valves 640FR, 640FL, 640RR, 640RL. The wheel cylinder 20RL is connected to a wheel cylinder 20RL (hereinafter referred to as “wheel cylinder 20” when they are not distinguished from each other). Hereinafter, the pressure increasing valves 640FR to 640RL are collectively referred to as “pressure increasing valve 640”. The pressure increasing valve 640 is a normally closed electromagnetic flow rate control valve (linear valve) that is closed when not energized and is used to increase the pressure of the wheel cylinder 20 as necessary. A disc brake unit is provided for each wheel of the vehicle (not shown), and each disc brake unit generates a braking force by pressing the brake pad against the disc by the action of the wheel cylinder 20.

  Further, the wheel cylinder 20FR for the right front wheel and the wheel cylinder 20FL for the left front wheel are connected to the hydraulic supply / discharge pipe J6 via the pressure reducing valve 642FR or 642FL, respectively. The pressure reducing valves 642FR and 642FL are normally closed electromagnetic flow control valves (linear valves) used for pressure reduction of the wheel cylinders 20FR and 20FL as necessary. On the other hand, the wheel cylinder 20RR for the right rear wheel and the wheel cylinder 20RL for the left rear wheel are connected to the hydraulic supply / discharge pipe J6 via a pressure reducing valve 642RR or 642RL that is a normally open electromagnetic flow control valve. . Hereinafter, the pressure reducing valves 642FR to 642RL are collectively referred to as “pressure reducing valve 642” as appropriate.

  In the vicinity of the wheel cylinders 20FR to 20RL for the right front wheel, the left front wheel, the right rear wheel, and the left rear wheel, a cylinder pressure that detects a wheel cylinder pressure that is a pressure of a brake fluid acting on the corresponding wheel cylinder 20 is detected. Sensors 644FR, 644FL, 644RR and 644RL are provided. Hereinafter, the cylinder pressure sensors 644FR to 644RL will be collectively referred to as “cylinder pressure sensor 644” as appropriate.

  Further, a bypass line I6 (functioning as a “connection flow path”) that connects the high-pressure line H6 and the line G is provided, and the bypass line I6 has a communication valve that is a normally open electromagnetic flow control valve. 655 (which functions as an “open / close valve”) is provided. A check valve 636 is provided between the connection point of the communication valve 655 in the high pressure line H6 and the accumulator 650, and the high pressure brake fluid accumulated in the accumulator 650 is transferred to the master cylinder 14 via the bypass line I6. The flow to the side is regulated.

  The shut-off valves 28 and 30, the pressure increasing valves 640 FR to 640 RL, the pressure reducing valves 642 FR to 642 RL, the pump 634, the accumulator 650, the communication valve 655, etc. constitute a hydraulic actuator 616 of the brake control device 610. The hydraulic actuator 616 is controlled by the brake ECU 206.

  The brake ECU 206 is composed mainly of a microcomputer including a CPU that outputs a control command to an actuator such as an electromagnetic control valve that controls each wheel cylinder pressure of the four wheels. In addition to the CPU, a ROM, a RAM, an input / output port, and a communication Provide ports. The CPU, input IC, and output IC of the brake ECU 206 are connected to an arbitration circuit that constitutes a drive circuit of the motor 632 via a communication line. The arbitration circuit includes an analog circuit that can turn on and off the motor 632 by a switch input in accordance with whether or not the accumulator pressure is within a set range, in addition to a command input from the CPU.

  The CPU calculates a target braking force and a control command value for each wheel based on signals input from various sensors including a hydraulic pressure sensor via the input IC, and outputs a command signal based on the calculation result via the output IC. Output to each electromagnetic control valve of each wheel. A stop lamp switch signal (hereinafter referred to as “STP signal”) is also input to the arbitration circuit.

  In the embodiment, the brake control process is executed centering on the CPU of the brake ECU 206. However, it is necessary to ensure braking force even when an unexpected abnormality occurs, such as when the CPU breaks down for some reason or the communication line between the CPU and each drive circuit is disconnected. Therefore, the embodiment has been devised for such a case.

  In the embodiment, at the time of failure of the CPU or the like, even if the driver depresses the brake pedal 12 and issues a braking request, the serial signal originally input from the CPU is not input to the arbitration circuit. The arbitration circuit drives the motor 632 as a fail-safe process and gives a braking force to a predetermined wheel when there is no signal input from the CPU even though the STP signal is input by depressing the brake pedal 12. .

  That is, when the CPU or the like of the brake ECU 206 fails, the actuators such as the electromagnetic control valve constituting the hydraulic actuator 616 are basically not energized and are brought into a normal state. When the brake pedal 12 is depressed in such a case, the arbitration circuit regards the motor as having failed because the serial signal input from the CPU is interrupted despite the STP signal being input. 632 is driven. In the embodiment, since it is possible to secure a braking force at the time of a failure by using a stop lamp switch that can be configured more simply and at a lower cost than the stroke sensor 22, even if a failure occurs in the CPU of the brake control device 610. Fail-safe control can be realized at low cost. In addition, since the stop lamp switch operates with no power supply, even if the power supply fails, fail-safe control can be executed reliably.

  When the motor 632 is driven in response to the STP signal, the pump 634 operates, so that the brake fluid is pumped up from the reservoir tank 24 and discharged. Since the communication valve 655 is in the open state, the discharged brake fluid is introduced into the primary chamber 14a via the bypass line I6, the line G, and the line B. As a result, the master cylinder pressure increases. At this time, since the shutoff valve 30 is in the open state, the brake fluid is supplied to the wheel cylinder 20FL of the left front wheel via the pipe line G. Further, since the on-off valve 26 is in the closed state and the shutoff valve 28 is in the open state, the brake fluid in the secondary chamber 14b is pushed out and is connected to the wheel cylinder 20FR of the right front wheel via the pipe line A and the pipe line F. Supplied. That is, even if the CPU or the like fails, a braking force can be applied to the front wheels (which may be drive wheels) as long as the brake pedal 12 is depressed.

  A drive circuit that drives the motor based on the STP signal when the CPU or the like fails is provided separately from the drive circuit that drives the motor when the CPU or the like is normal. In the embodiment, a plurality of motor drive circuits that are operated under still another condition are provided. It is necessary to check whether a motor drive circuit that is not used in normal operation operates normally when the CPU or the like fails before the CPU or the like fails. It is also necessary to check whether the arbitration circuit that supplies the output of the motor drive circuit to the motor operates normally. Therefore, the brake ECU includes an analog circuit shown in FIG.

  FIG. 2 is a diagram illustrating a functional configuration of the brake ECU according to the embodiment. The brake ECU 206 includes a second motor drive circuit 208, a third motor drive circuit 210, a first motor drive circuit 212, a first logic unit 214, a second logic unit 215, a third logic unit 216, a fourth logic unit 220, and a CPU 222. And an input / output IC 224. The CPU 222 and the input / output IC 224 function as a control unit 230 that controls driving of the motor 632. The first logic unit 214, the second logic unit 215, the third logic unit 216, the fourth logic unit 220, and the wiring thereof function as an arbitration circuit 232 that can supply the output of each motor drive circuit to the motor.

  The CPU 222 controls driving of the motor 632 and controls brakes applied to the wheels. The CPU 222 calculates the target braking force and control command value of each wheel based on signals input from various sensors (not shown) including the hydraulic pressure sensor via the input / output IC 224, and command signals based on the calculation results. Is output to each electromagnetic control valve and motor 632 of each wheel via the input / output IC 224. For example, when the accumulator pressure becomes 8 MPa or less, the CPU 222 drives the motor 632 to control the accumulator pressure to be greater than 8 MPa. Further, the CPU 222 outputs a signal indicating the normality of the CPU 222 to the fourth logic unit 220 when the CPU 222 is operating normally.

  The input / output IC 224 includes a normal motor drive circuit 234 that generates a drive signal for driving the motor 632 when the CPU 222 and the input / output IC 224 are normal. When the CPU 222 and the input / output IC 224 are not normal, the input / output IC 224 may output a signal indicating motor drive off to the third logic unit 216. The input / output IC 224 receives a command signal for the motor 632 from the CPU 222 and outputs a drive signal for the motor 632 to the third logic unit 216 so as to go to the motor 632. The input / output IC 224 outputs a signal indicating normality of the input / output IC 224 to the fourth logic unit 220 when the input / output IC 224 is operating normally. Whether the CPU 222 and the input / output IC 224 are normal or not may be checked by sending a signal to each other and checking the response signal. Further, another program for checking whether the CPU 222 and the input / output IC 224 are normal may be included.

  When receiving a signal indicating normality from each of the CPU 222 and the input / output IC 224, the fourth logic unit 220 outputs a signal indicating normality to the second logic unit 215 and the first motor drive circuit 212. On the other hand, when receiving a signal indicating abnormality from either the CPU 222 or the input / output IC 224, the fourth logic unit 220 outputs a signal indicating abnormality to the second logic unit 215 and the first motor drive circuit 212. That is, if a signal indicating normality is not output from either the CPU 222 or the input / output IC 224, the fourth logic unit 220 outputs a signal indicating abnormality to the second logic unit 215 and the first motor drive circuit 212.

  The first motor drive circuit 212, the second motor drive circuit 208, and the third motor drive circuit 210 are circuits for driving the motor 632 when the CPU 222 and the input / output IC 224 fail, and each predetermined operating condition When the above is established, a drive signal for the motor 632 is output.

  The third motor drive circuit 210 starts operating when the brake ECU 206 is activated, and operates until the power source of the brake ECU 206 is turned off. The third motor drive circuit 210 outputs a drive signal so that the motor 632 is intermittently driven. Thereby, the heating of the brush of the motor 632 which is a brush motor can be suppressed. The intermittent drive refers to, for example, driving the motor 632 for several seconds, then stopping the motor 632 for several seconds, and repeating this driving and stopping.

  The first motor drive circuit 212 is operated based on a signal indicating whether or not the CPU 222 and the input / output IC 224 are abnormal. That is, the first motor drive circuit 212 starts operation when receiving a signal indicating abnormality of the CPU 222 and the input / output IC 224, and ends operation when a predetermined time elapses. This predetermined time is set to a time of 1 minute or less, for example. As a result, when the CPU 222 and the input / output IC 224 fail, it is possible to suppress a decrease in the pressure of the accumulator 650 immediately after the failure, and to compensate for an insufficient increase in the accumulator pressure by the third motor drive circuit 210.

  The second motor drive circuit 208 is operated based on the STP signal. That is, the second motor drive circuit 208 starts operation when it receives the STP signal indicating ON. The second motor drive circuit 208 stops operating after a predetermined period has elapsed since the STP signal was turned off.

  Each motor drive circuit is connected to the first logic unit 214 in parallel. The first logic unit 214 selects one of the drive signals of each motor drive circuit and outputs the drive signal to the second logic unit 215 so as to go to the motor 632.

  Each motor drive circuit outputs a signal indicating that it is not operating when it is not operating to the first logic unit 214, and the first logic unit 214 is based on the signal indicating that it is not operating. A drive signal may be selected. Further, the first logic unit 214 preferentially selects and outputs the output signals of the second motor drive circuit 208, the first motor drive circuit 212, and the third motor drive circuit 210 from the second motor drive circuit 208 in order. Good.

  The output of the first logic unit 214 is input to the input / output IC 224. The first logic unit 214 can reduce the number of parts compared to the case where each motor drive circuit is output individually.

  The second logic unit 215 receives a valid drive signal output from the first logic unit 214 and a signal indicating abnormality of the CPU 222 or the input / output IC 224 from the fourth logic unit 220 from the first logic unit 214. The output drive signal is output to the third logic unit 216 so as to go to the motor 632. On the other hand, when the second logic unit 215 receives signals indicating normality of the CPU 222 and the input / output IC 224 from the fourth logic unit 220, the second logic unit 215 does not output the drive signal output from the first logic unit 214. When the second logic unit 215 does not output the drive signal output from the first logic unit 214, the second logic unit 215 may output a signal indicating motor drive off to the third logic unit 216.

  The third logic unit 216 is connected to the second logic unit 215 and the control unit 230. The third logic unit 216 outputs one of the signals output from the second logic unit 215 and the control unit 230 to the motor 632. The third logic unit 216 may select which signal to output based on whether the signals output from the second logic unit 215 and the control unit 230 indicate that the motor drive is off. For example, when the control unit 230 is abnormal, a signal output from the second logic unit 215 is output to the motor 632, and when the control unit 230 is normal, a drive signal of the motor 632 output from the input / output IC 224 is output. Output to the motor 632.

As described above, when the CPU 222 and the input / output IC 224 fail, the motor 632 can be driven through a simple analog arbitration circuit.
Here, when the CPU 222 and the input / output IC 224 fail, it is safer to monitor whether each motor drive circuit operates normally and whether each logic unit operates normally. Therefore, the CPU 222 checks the operating state of the arbitration circuit and each motor drive circuit. In the process of checking the operation state of each motor drive circuit, the operation state of each motor drive circuit and the arbitration circuit relaying the CPU 222 can also be checked.

  The CPU 222 outputs a signal indicating an abnormality of the control unit 230 before the control unit 230 becomes abnormal. The CPU 222 may output a signal indicating an abnormality of the control unit 230 when the ignition switch is turned on from off. Thus, the operating state of the motor drive circuit can be inspected before the vehicle immediately after the start of driving starts.

  FIG. 3 is a flowchart showing a process for checking the operating state of the motor drive circuit according to the embodiment. In this process, the operating state of the first motor drive circuit 212 is checked. This process may be performed when the brake ECU 206 is activated. Further, this process may be executed every time the brake ECU 206 is activated a predetermined number of times, not every time the brake ECU 206 is activated.

  First, the CPU 222 determines whether the ignition switch is turned on (S10). In this process, any other method may be used as long as it can be confirmed that the power source of the brake ECU 206 is turned on. Thereby, the presence or absence of the operation | movement of the 3rd motor drive circuit 210 can be confirmed. If the ignition switch is not turned on (N in S10), the CPU 222 ends this process.

  If the ignition switch is turned on (Y in S10), the CPU 222 determines whether the CPU 222 and the input / output IC 224 are outputting signals indicating normality (S12). The CPU 222 may check whether the input / output IC 224 is normal. As a result, the signal output from the fourth logic unit 220 is confirmed, and the presence or absence of the operation of the first motor drive circuit 212 is confirmed. If either of the CPU 222 and the input / output IC 224 does not output a signal indicating normality (N in S12), the process is terminated.

  If the CPU 222 and the input / output IC 224 output a signal indicating normality (Y in S12), the CPU 222 determines whether or not the stop lamp switch is turned on (S14). Thereby, the presence or absence of the operation | movement of the 2nd motor drive circuit 208 can be confirmed. If the stop lamp switch is turned on (Y in S14), the process is terminated. This is because the operating condition of the second motor drive circuit 208 is established if the stop lamp switch is on. In this case, this process may be retried.

  If the stop lamp switch is not turned on (N in S14), the CPU 222 outputs a signal indicating an abnormality from the CPU 222 or the input / output IC 224 to the fourth logic unit 220 (S16). As a result, a signal indicating an abnormality of the CPU 222 or the input / output IC 224 is input to the first motor drive circuit 212 via the fourth logic unit 220, and the operating condition of the first motor drive circuit 212 is established.

  The CPU 222 receives the output of the first logic unit 214 via the input / output IC 224, and determines whether a signal indicating the drive signal of the first motor drive circuit 212 is output from the first logic unit 214 (S18). If a valid drive signal for the motor 632 is output from the first logic unit 214 for a predetermined time in response to a signal indicating an abnormality of the CPU 222 or the input / output IC 224 being input to the fourth logic unit 220, the CPU 222 It is determined that a signal indicating the drive signal of the first motor drive circuit 212 is output from the first logic unit 214.

  If a valid signal indicating the drive signal of the first motor drive circuit 212 is not output from the first logic unit 214 (N in S18), the CPU 222 determines that the first motor drive circuit 212 is abnormal (S22). . The CPU 222 may determine that there is an abnormality in the first motor drive circuit 212 or the first logic unit 214. At this time, the CPU 222 may notify the driver of an alarm indicating an abnormality of the first motor drive circuit 212.

  On the other hand, if a signal indicating the drive signal of the first motor drive circuit 212 is output from the first logic unit 214 (Y in S18), the CPU 222 determines that the first motor drive circuit 212 is normal (S20). . As described above, the operating state of the first motor drive circuit 212 can be checked before an abnormality occurs in the CPU 222 or the like.

  Next, a process for checking the operating state of the third motor drive circuit 210 will be described. The third motor drive circuit 210 operates when the power of the brake ECU 206 is turned on, and outputs a drive signal for intermittently driving the motor 632. Then, the first logic unit 214 outputs the drive signal of the third motor drive circuit 210 if the valid drive signals output from the second motor drive circuit 208 and the first motor drive circuit 212 are not output. Therefore, if the operating conditions of the second motor drive circuit 208 and the first motor drive circuit 212 are not satisfied, the drive signal of the third motor drive circuit 210 is the first unless the third motor drive circuit 210 and its relay are abnormal. 1 is output from the logic unit 214.

  Therefore, the CPU 222 drives the third motor from the first logic unit 214 when the ignition switch is turned on, signals indicating normality of the CPU 222 and the input / output IC 224 are output, and the stop lamp switch is not turned on. It is determined whether a valid signal indicating the driving signal of the circuit 210 is output. If the signal output from the first logic unit 214 is a drive signal for driving the motor 632 intermittently, the CPU 222 determines that the signal is a drive signal output from the third motor drive circuit 210. If the drive signal output by the third motor drive circuit 210 is not output from the first logic unit 214, the CPU 222 determines that the third motor drive circuit 210 is abnormal. At this time, the CPU 222 may have an abnormality in the third motor driving circuit 210 or the first logic unit 214. On the other hand, if the drive signal output by the third motor drive circuit 210 is output from the first logic unit 214, the CPU 222 determines that the third motor drive circuit 210 is normal. Thus, the operating state of the third motor drive circuit 210 can be checked.

  Next, a process for checking the operating state of the second motor drive circuit 208 will be described. The second motor drive circuit 208 operates when an STP signal indicating ON is input. Therefore, when the inspection process is started, the CPU 222 first receives the STP signal and monitors whether the STP signal indicates ON. If the STP signal indicates ON, the CPU 222 receives the output of the first logic unit 214 and determines whether a valid drive signal for the motor 632 is output according to the STP signal.

  Specifically, the CPU 222 checks whether the second motor drive circuit 208 starts outputting the drive signal in response to the STP signal being turned on and stops outputting the drive signal in response to the STP signal being turned off. Thus, the CPU 222 can check the operating state of the second motor drive circuit 208. Note that the CPU 222 may generate an STP signal and output an STP signal indicating ON to the second motor drive circuit 208 to check the operating state of the second motor drive circuit 208. As described above, whether or not each motor drive circuit is abnormal can be checked based on the output of the first logic unit 214.

  Further, the CPU 222 checks the operating state of each logic unit and its relay. Therefore, the CPU 222 acquires the output of the third logic unit 216. Further, instead of the output of the third logic unit 216, the CPU 222 may acquire a signal indicating that the motor 632 is driven from the motor relay circuit (not shown) when the motor 632 is driven. Good. That is, the CPU 222 acquires a signal indicating the driving state of the motor 632. The motor relay circuit electrically connects the third logic unit 216 and the motor 632. In addition, the control unit 230 may receive the output of the second logic unit 215 for inspection.

  First, a process for checking the operating state of the first logic unit 214 will be described. When the operating state of each motor drive circuit is inspected based on the output of the first logic unit 214, if there is no abnormality in each motor drive circuit, the first logic unit 214 is normal. In the inspection of the operation state of each motor drive circuit, if it is determined that all the operation states of each motor drive circuit are abnormal, the CPU 222 may determine that the first logic unit 214 is abnormal. The CPU 222 checks the operating state of the first logic unit 214 along with checking each motor drive circuit.

  Processing for checking the operating state of the fourth logic unit 220 will be described. When the operating state of the first motor driving circuit 212 is checked, if the first motor driving circuit 212 is operating in accordance with an output signal indicating the operating state of the CPU 222 or the input / output IC 224, the CPU 222 includes the fourth logic unit 220. Is determined to be normal. On the other hand, the first motor drive circuit 212 does not operate in response to the output signal indicating the operation state of the CPU 222 or the input / output IC 224 and the signal output from the first logic unit 214 is not output from the second logic unit 215. The CPU 222 determines that the fourth logic unit 220 is abnormal. The CPU 222 may check the operating state of the fourth logic unit 220 together with checking the first motor drive circuit 212.

  Processing for checking the operating state of the third logic unit 216 will be described. The state of the relay connecting the third logic unit 216 and the input / output IC 224 is checked. The CPU 222 receives a signal indicating the driving state of the motor 632. When the input / output IC 224 is normal, the drive signal for the motor 632 corresponding to the accumulator pressure is output from the input / output IC 224. Therefore, the CPU 222 checks whether the drive signal of the motor 632 corresponding to the accumulator pressure is output from the third logic unit 216 as in the output of the input / output IC 224. Further, the CPU 222 checks whether the motor 632 is driven according to the accumulator pressure. Specifically, the CPU 222 checks whether the motor 632 is driven when the accumulator pressure becomes 15 Mpa or less. Similarly to the output of the input / output IC 224, the CPU 222 has a normal system for connecting the third logic unit 216 and the input / output IC 224 if the drive signal of the motor 632 corresponding to the accumulator pressure is output from the third logic unit 216. It is determined that

  Processing for checking the operating state of the second logic unit 215 will be described. As described above, since the CPU 222 can check each motor drive circuit regardless of the operation state of the second logic unit 215 and the third logic unit 216, it checks that each motor drive circuit is normal. The second logic unit 215 may be checked later using each motor drive circuit.

  When a signal indicating abnormality of the CPU 222 or the input / output IC 224 is output, the first motor drive circuit 212 is normal, and the motor 632 is not driven for a predetermined time according to the drive signal of the first motor drive circuit 212. The CPU 222 determines that either the second logic unit 215 or its wiring is abnormal. At this time, the CPU 222 may acquire the output of the second logic unit 215. As described above, the CPU 222 may check the operating state of the second logic unit 215 by acquiring the signal indicating the driving state of the motor 632 as well as checking the first motor driving circuit 212. As a result, the inspection time is shortened and the trouble of outputting a signal indicating abnormality of the CPU 222 or the input / output IC 224 can be saved. When a signal indicating normality of the CPU 222 or the input / output IC 224 is output, the CPU 222 indicates that the second logic unit 215 is abnormal if the second logic unit 215 outputs the drive signal of the third motor drive circuit 210. Is determined. If the third logic unit 216 is normal by inspection, the CPU 222 may determine that the second logic unit 215 is also normal. As described above, the operating state of the arbitration circuit that supplies the output of each motor drive circuit to the motor can be checked.

In addition, the above-mentioned embodiment contains the aspect shown below.
The brake control device receives a control means for controlling the motor that drives the pump, a plurality of motor drive circuits that individually output motor drive signals, and a signal indicating an abnormality of the control means. An arbitration circuit that supplies an output of the motor drive circuit to the motor. The arbitration circuit includes first logic means for selecting and outputting any one of the drive signals of the plurality of motor drive circuits. The control means receives the signal output from the first logic means, and checks the operating states of the plurality of motor drive circuits based on the signal. As a result, the outputs of the plurality of motor drive circuits can be combined into one by the first arbitration means, and the operating states of the plurality of motor drive circuits can be checked based on the outputs.

  The arbitration circuit outputs a drive signal output from the first logic means to the motor when receiving the drive signal output from the first logic means and a signal indicating abnormality of the control means. Logic means are further provided. Thereby, the second logic means can output the motor drive signal output from any of the plurality of motor drive circuits when an abnormality occurs in the control means.

  The arbitration circuit further includes third logic means for outputting one of the signals output from the second logic means and the control means to the motor. The first motor drive circuit among the plurality of motor drive circuits operates when a signal indicating abnormality of the control means is input, and the control means sends a signal indicating abnormality of the control means to the first motor drive circuit. The operating state of the first motor drive circuit is inspected based on whether the signal input and output from the first logic means is the drive signal output from the first motor drive circuit. When the control means inputs a signal indicating the abnormality of the control means itself to the first motor drive circuit, it is possible to check whether the first motor drive circuit operates normally before the control means becomes abnormal.

  The second motor drive circuit among the plurality of motor drive circuits operates when the stop lamp switch is turned on, and the control means is output from the first logic means when the stop lamp switch is turned on. The operating state of the second motor drive circuit is checked based on whether the received signal is a drive signal output from the second motor drive circuit. Thereby, the operating state of the 2nd motor drive circuit which operate | moves according to a stop lamp switch can be inspected.

  The third motor drive circuit among the plurality of motor drive circuits outputs a drive signal for intermittently driving the motor, and the control means outputs a signal indicating normality from the control means with the stop lamp switch turned off. Sometimes, the operating state of the third motor drive circuit is checked based on whether the signal output from the first logic means is the drive signal output from the third motor drive circuit. Thereby, the operating state of the third motor drive circuit can be checked.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added to the embodiments based on the knowledge of those skilled in the art, and such modifications have been added. Embodiments may also be included within the scope of the present invention.

  For example, the configuration of the arbitration circuit shown in FIG. 2 can be used by changing each motor drive circuit that drives the motor in the event of an abnormality according to the type of the brake control device.

  H1, J1, H2, J2, I3, J3, I4, J4 pipe, H6 high pressure pipe, I6 bypass pipe, J6 hydraulic supply / discharge pipe, 12 brake pedal, 14 master cylinder, 14a primary chamber, 14b secondary chamber, 15 Push rod, 16 Hydraulic actuator, 20FL, 20FR, 20RL, 20RR Wheel cylinder, 22 Stroke sensor, 24 Reservoir tank, 25 Stroke simulator, 26 Open / close valve, 28, 30 Shut-off valve, 70, 72 Hydraulic sensor, 206 Brake ECU, 208 second motor drive circuit, 210 third motor drive circuit, 212 first motor drive circuit, 214 first logic unit, 215 second logic unit, 216 third logic unit, 220 fourth logic unit, 222 CPU, 224 entering Output IC, 230 control unit, 232 arbitration circuit, 234 normal motor drive circuit, 610 brake control device, 616 hydraulic actuator, 632 motor, 634 pump, 636 check valve, 640, 640FR pressure increase valve, 642, 642FR, 642RR pressure reduction Valve, 644, 644FR cylinder pressure sensor, 650 accumulator, 651 accumulator pressure sensor, 653 relief valve, 655 communication valve.

Claims (3)

Control means for controlling a motor for driving the pump;
A plurality of motor drive circuits for driving the motor when the control means is abnormal, each of which individually outputs a drive signal of the motor, and a plurality of motor drive circuits arranged in parallel;
An arbitration circuit that, when receiving a signal indicating an abnormality of the control means, selects and outputs any one of the plurality of drive signals of the motor drive circuit, and supplies the drive signal to the motor And comprising
The control means indicates an abnormality of the control means in order to check the operation states of the plurality of motor drive circuits when the control means is normal in the process of checking the operation states of the plurality of motor drive circuits. A brake control device that outputs a signal and checks the operating state of the motor drive circuit based on the drive signal of the motor drive circuit received from the arbitration circuit.   2. The brake control according to claim 1, wherein the first motor drive circuit among the plurality of motor drive circuits outputs a drive signal of the motor when a signal indicating an abnormality of the control means is input. apparatus. 3. The brake control device according to claim 1, wherein the control means outputs a signal indicating an abnormality of the control means when the ignition switch is turned on from off. 4.

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