JP5292259B2 - Current supply circuit and brake control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a current supply circuit that detects a faulty regulator. <P>SOLUTION: The current supply circuit 110 includes: a first regulator 214 and a second regulator 224 arranged in parallel between a battery 300 and a simulator cut valve SCSS; a first current monitor 215 and a second current monitor 225 arranged in parallel; a first control part 216 for controlling the output current of the first regulator 214; and a second control part 226 for controlling the output current of the second regulator 224. When a failure of the first regulator 214 and the second regulator 224 is estimated, the first control part 216 and the second control part 226 cause the first regulator to output a predetermined first current pattern, and causes the second regulator 224 to output a predetermined second current pattern which is different from the first current pattern. Then, on the basis of the current pattern detected by the first current monitor 215 and the second current monitor 225, the faulty regulator is determined. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a current supply circuit capable of supplying current to a supply object using a plurality of regulators, and a brake control device using the current supply circuit.

  2. Description of the Related Art Conventionally, a so-called brake-by-wire type brake control device is known that adjusts the hydraulic pressure supplied to each wheel cylinder by electronically controlling the supply of brake fluid to a plurality of wheel cylinders via a hydraulic circuit. (For example, refer to Patent Document 1).

  The brake control device described in Patent Document 1 is provided in each of the four main pipelines connecting the master reservoir storing brake fluid and each wheel cylinder, and the branched main pipelines, and is stored in the master reservoir. A pump that sucks and discharges the brake fluid and pressurizes each wheel cylinder. The brake control device includes a first piping system that supplies brake fluid to a right front wheel wheel cylinder and a left rear wheel wheel cylinder via a main line, a left front wheel wheel cylinder, and a right rear wheel wheel cylinder. And a second piping system for supplying brake fluid via the main pipeline. Further, the brake control device includes an auxiliary pipeline that connects a master cylinder provided so that a brake pedal as a brake operation member can enter and a wheel cylinder of the left and right front wheels. Further, the auxiliary pipe line is provided with a stroke simulator that accommodates the brake fluid sent from the master cylinder by the operation of the brake pedal and generates a reaction force according to the operation of the brake pedal. In addition, a simulator cut valve provided in the middle of the flow path connecting the master cylinder and the stroke simulator is provided.

  In such a configuration, when the brake pedal is depressed, the wheel cylinder pressure corresponding to the pedal depression force is calculated, and each of the first reservoir system and the second pipeline system controls each of the master reservoirs to obtain the calculated wheel cylinder pressure. Brake fluid is supplied to the wheel cylinder. In addition, a stroke simulator is used to give a driver a resistance when the brake pedal is operated according to an increase in wheel cylinder pressure, that is, a brake feeling. Specifically, when the brake pedal is depressed, a predetermined amount of brake fluid moves from the master cylinder to the stroke simulator, and a reaction force corresponding to the depression of the brake pedal is generated by the stroke simulator. As a result, the brake pedal is provided with a feeling of resistance corresponding to the increase in the wheel cylinder pressure to give the driver a good brake feeling.

JP 2007-137258 A

  By the way, the above-mentioned simulator cut valve is a normally closed electromagnetic control valve that is normally opened by receiving supply of a prescribed control current, and is closed when in a non-energized state. While the system braking force control is being performed, it is necessary to maintain the energized state of the simulator cut valve. Therefore, from the viewpoint of fail-safe, it is preferable that the current supply to the simulator cut valve is performed by a plurality of (for example, two) systems.

  For example, when the simulator cut valve is energized by two systems, a method of energizing by providing a first regulator and a second regulator in parallel with the simulator cut valve can be considered. In this case, a first current monitor and a second current monitor are provided in parallel downstream of the simulator cut valve, and the first regulator is based on the detection value of the first current monitor and the second is based on the detection value of the second current monitor. The regulator is controlled.

  In such a current supply circuit, for example, when an abnormality occurs in the first regulator, the current supplied from the second regulator to the simulator cut valve also flows in the first current monitor used for controlling the first regulator. Therefore, the current value is detected from both the first current monitor and the second current monitor, and it cannot be determined which regulator has an abnormality.

  The present invention has been made in view of such a situation, and an object of the present invention is to detect an abnormal regulator in a current supply circuit capable of supplying current to a supply object using a plurality of regulators. An object of the present invention is to provide a current supply circuit that can be used, and a brake control device using the current supply circuit.

  In order to solve the above problems, a current supply circuit according to an aspect of the present invention is a current supply circuit that supplies current from a power source to an object to be supplied, and is arranged in parallel between the power source and the object to be supplied. A first current monitor and a second regulator, a first current monitor and a second current monitor arranged in parallel between the supply object and ground for detecting a current flowing through the supply object; First control means for controlling the output current of the first regulator based on the current value detected by the current monitor, and the output current of the second regulator based on the current value detected by the second current monitor The second control means for controlling the abnormality, the abnormality estimation means for estimating the abnormality of the first regulator and the second regulator, and when the abnormality is estimated by the abnormality estimation means, The regulator instructs the first control means to output a predetermined first current pattern, and the second regulator instructs the second control means to output a predetermined second current pattern different from the first current pattern. Current pattern indicating means, and determination means for determining a regulator in which an abnormality has occurred based on current patterns detected in the first current monitor and the second current monitor.

  According to this aspect, it can be determined whether an abnormality has occurred in the first regulator or the second regulator. That is, when only the first current pattern is detected, it can be determined that the second regulator is abnormal, and when only the second current pattern is detected, it can be determined that the first regulator is abnormal.

  The current supply circuit supplies current to an electromagnetic control valve that opens or closes by supplying a current that is equal to or greater than a predetermined valve driving current, and the first current pattern and the second current pattern are the lowest current. It may be a current pattern whose value is set to be equal to or greater than the valve drive current. In this case, an abnormal regulator can be detected while continuing to drive the electromagnetic control valve.

  Another aspect of the present invention is a brake control device. This device is a brake control device that generates hydraulic pressure in a wheel cylinder by supplying brake fluid via a hydraulic pressure circuit, and applies braking force to a wheel by the hydraulic pressure, and brakes the stored brake fluid. A master cylinder that pressurizes according to the operation of the operation member, a stroke simulator that generates a reaction force against the operation of the brake operation member by supplying brake fluid from the master cylinder, and a flow that communicates the master cylinder and the stroke simulator. A simulator cut valve provided in the middle of the road; and a current supply circuit that supplies current to the simulator cut valve from a power source. The current supply circuit detects a current flowing through the simulator cut valve and a first regulator and a second regulator arranged in parallel between the power source and the simulator cut valve, and between the simulator cut valve and the ground. A first current monitor and a second current monitor arranged in parallel with each other; a first control means for controlling an output current of the first regulator based on a current value detected by the first current monitor; A second control unit configured to control an output current of the second regulator based on a current value detected by the two current monitor; an abnormality estimation unit configured to estimate an abnormality of the first regulator and the second regulator; When an abnormality is estimated by the estimating means, the first control means is configured so that the first regulator outputs a predetermined first current pattern. Current pattern indicating means for instructing the second control means to output a predetermined second current pattern different from the first current pattern by the second regulator, the first current monitor and the second current Determination means for determining a regulator in which an abnormality has occurred based on a current pattern detected by the monitor.

  According to this aspect, it can be determined whether an abnormality has occurred in the first regulator or the second regulator that supplies current to the simulator cut valve. That is, when only the first current pattern is detected, it can be determined that the second regulator is abnormal, and when only the second current pattern is detected, it can be determined that the first regulator is abnormal.

  The simulator cut valve is an electromagnetic control valve that opens or closes by supplying a current greater than or equal to a predetermined valve drive current, and the first current pattern and the second current pattern have the lowest current value as the valve drive current. The current pattern set above may be used. In this case, an abnormal regulator can be detected while continuing to drive the simulator cut valve. Therefore, it is possible to detect an abnormal regulator without causing the driver to feel uncomfortable.

  According to the present invention, in a current supply circuit capable of supplying current to a supply object using a plurality of regulators, a current supply circuit capable of detecting a regulator in which an abnormality has occurred, and the current supply circuit are used. The brake control device which was able to be provided can be provided.

It is a schematic block diagram of the hydraulic circuit in the brake control apparatus which concerns on embodiment of this invention. It is a figure for demonstrating the structure of the electric current supply circuit which supplies an electric current from a battery to a simulator cut valve. It is a flowchart for demonstrating the abnormal regulator detection process which concerns on this embodiment. 4A and 4B are diagrams for explaining an example of the first current pattern and the second current pattern. It is a schematic block diagram of the hydraulic circuit in the brake control apparatus which concerns on another embodiment of this invention.

  Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate.

  FIG. 1 is a schematic configuration diagram of a hydraulic circuit in a brake control device according to an embodiment of the present invention. The brake control device 100 according to the present embodiment supplies a brake fluid to a first piping system that supplies brake fluid to a wheel cylinder for a right front wheel and a left rear wheel, and to a wheel cylinder for a left front wheel and a right rear wheel. A so-called X piping structure including the second piping system.

  As shown in FIG. 1, the brake control device 100 includes a brake pedal 1 (brake operation member), a pedaling force sensor 2, a master cylinder 3, a simulator cut valve SCSS, a stroke simulator 4, and a hydraulic actuator 5. The brake control device 100 is built in brake discs FR, RL, FL, RR provided on the right front wheel, left rear wheel, left front wheel, and right rear wheel (all not shown) of the vehicle, and the brake caliper, respectively. And a disc brake unit including wheel cylinders 6FR, 6RL, 6FL, 6RR (hereinafter collectively referred to as “wheel cylinder 6” as appropriate). Each wheel cylinder 6 is connected to the hydraulic actuator 5 via a different brake fluid flow path. In addition, the brake control device 100 includes a brake ECU 200 as a control unit that controls the operation of each unit of the brake control device 100.

  In each disc brake unit, brake fluid is supplied to the wheel cylinder 6 from the hydraulic actuator 5, and brake pads (not shown) are provided on the brake discs FR, RL, FL, RR that rotate together with each wheel by the hydraulic pressure of the brake fluid. Pressed. Thereby, a braking force is applied to each wheel. In this embodiment, the disc brake unit is used, but other braking force applying mechanisms such as a drum brake may be used.

  When the brake pedal 1 is depressed by the driver, the depression force of the brake pedal 1 (the force with which the driver steps on the brake pedal 1) is input to the depression force sensor 2. The pedaling force sensor 2 transmits a signal representing the input pedaling force value to the brake ECU 200. Although the pedaling force sensor 2 is used here as an operation amount sensor for detecting the operation amount of the brake pedal 1, a stroke sensor or the like that detects the stroke of the brake pedal 1 may be used.

  The master cylinder 3 pressurizes the stored brake fluid by operating the brake pedal 1 by the driver, and sends the brake fluid toward the wheel cylinder 6. The master cylinder 3 includes a primary chamber 3a, a secondary chamber 3b, a primary piston 3c, a secondary piston 3d, and a spring 3e.

  The master cylinder 3 is partitioned into a primary chamber 3a and a secondary chamber 3b by a primary piston 3c and a secondary piston 3d. A push rod extending from the brake pedal 1 is connected to the primary piston 3c. The primary piston 3c presses the push rod so as to return the brake pedal 1 to the initial position side when the brake pedal 1 is not depressed due to the elastic force of the spring 3e. The secondary piston 3d also receives the elastic force of the spring 3e and presses the push rod via the primary piston 3c. When the brake pedal 1 is depressed by the driver, the push rod enters the master cylinder 3, and the primary piston 3c and the secondary piston 3d are pressed. Thereby, the stored brake fluid is pressurized, and a master cylinder pressure is generated in the primary chamber 3a and the secondary chamber 3b.

  The primary chamber 3a and the secondary chamber 3b of the master cylinder 3 are connected with a pipeline B and a pipeline A that extend toward the hydraulic actuator 5, respectively.

  The master cylinder 3 is connected to a reservoir tank 3f that stores brake fluid. The reservoir tank 3f is connected to each of the primary chamber 3a and the secondary chamber 3b via a passage (not shown) when the brake pedal 1 is in the initial position, and supplies the brake fluid into the master cylinder 3 or within the master cylinder 3 Of excess brake fluid. A pipeline C and a pipeline D extending toward the hydraulic actuator 5 are connected to the reservoir tank 3f.

  The stroke simulator 4 is connected to a pipeline E connected to the pipeline A, and plays a role of containing brake fluid in the secondary chamber 3 b of the master cylinder 3. A simulator cut valve SCSS is provided in a pipeline E that is a part of a flow path that communicates the master cylinder 3 and the stroke simulator 4. Therefore, the stroke simulator 4 is connected to the pipe line A through the simulator cut valve SCSS. The simulator cut valve SCSS has a solenoid and a spring that are controlled to be turned on / off, and is opened by an electromagnetic force generated by the solenoid by supplying a current greater than a predetermined valve drive current, and the solenoid is in a non-energized state This is a normally-closed electromagnetic control valve that is in a closed state. When the simulator cut valve SCSS is in the closed state, the flow of brake fluid between the pipe line A and the stroke simulator 4 is blocked. When the solenoid is energized and the simulator cut valve SCSS is opened, the brake fluid can be circulated bidirectionally between the stroke simulator 4 and the master cylinder 3.

  The stroke simulator 4 includes a plurality of pistons and springs, and creates a reaction force according to the depression force of the brake pedal 1 by the driver when the simulator cut valve SCSS is opened. Specifically, when the brake pedal 1 is depressed with a predetermined depression force, the brake fluid in the secondary chamber 3 b is sent to the stroke simulator 4 via the pipeline A and the pipeline E. When the brake fluid flows into the stroke simulator 4, a hydraulic pressure is generated in the stroke simulator 4, whereby a reaction force is created in the stroke simulator 4. The brake pedal 1 enters the master cylinder 3 until the pedaling force and the reaction force are equal. That is, the stroke stroke of the brake pedal 1 corresponding to the depression force of the brake pedal 1 is created by the stroke simulator 4. As the stroke simulator 4, it is preferable to employ one having multistage spring characteristics in order to improve the feeling of brake operation by the driver.

  The hydraulic actuator 5 includes a pipeline F that connects the secondary chamber 3b of the master cylinder 3 and the wheel cylinder 6FR. One end of the pipe F is connected to the pipe A, the other end is connected to the downstream side of the pump 7 of the individual pipe H1 described later, and a master cut valve SMC1 is provided in the middle. Further, the hydraulic actuator 5 includes a pipeline G that connects the primary chamber 3a of the master cylinder 3 and the wheel cylinder 6FL. One end of the pipe G is connected to the pipe B, the other end is connected to the downstream side of the pump 9 of the individual pipe I3 described later, and a master cut valve SMC2 is provided in the middle.

  The master cut valves SMC1 and SMC2 have solenoids and springs that are controlled to be turned on / off, and are closed by electromagnetic force generated by the solenoids when supplied with a prescribed control current, and the solenoids are not energized. The normally open electromagnetic control valve is in a valve open state when When the master cut valves SMC1, SMC2 are in the open state, the brake fluid can be circulated bidirectionally between the master cylinder 3 and the pipelines F, G. When a prescribed control current is supplied to the solenoid and the master cut valves SMC1, SMC2 are closed, the flow of the brake fluid in the pipes A, B is interrupted. That is, when the master cut valves SMC1, SMC2 are closed, the supply of brake fluid to the wheel cylinders 6FR, 6FL by the master cylinder 3 is shut off.

  The hydraulic actuator 5 includes a pipe H connected to a pipe C extending from the reservoir tank 3f and a pipe I connected to a pipe D similarly extending from the reservoir tank 3f. The pipe H is branched into two pipes called individual pipes H1 and H2, and the individual pipe H1 is connected to the wheel cylinder 6FR and the individual pipe H2 is connected to the wheel cylinder 6RL. Further, the pipe I branches into two pipes called individual pipes I3 and I4, and the individual pipe I3 is connected to the wheel cylinder 6FL and the individual pipe I4 is connected to the wheel cylinder 6RR.

  Each individual pipe H1, H2, I3, I4 is provided with one pump 7, 8, 9, 10 respectively. Each pump 7-10 is comprised by the trochoid pump excellent in silence, for example. 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.

  Further, the hydraulic actuator 5 includes pipe lines J1, J2, J3, and J4 arranged in parallel to each of the pumps 7 to 10. A pipe line J1 arranged in parallel with the pump 7 connects the upstream side and the downstream side of the pump 7 so as to bypass the pump 7. In the present embodiment, the pipe J1 has one end connected to the pipe H located on the upstream side of the pump 7 and the other end connected to the pipe F located on the downstream side of the pump 7. Further, a communication valve SRC1 and a hydraulic pressure adjustment valve SLFR are provided in series in the middle of the pipe line J1. The communication valve SRC1 is on the suction port side of the pump 7 (downstream side in the brake fluid flow direction in the pipe line J1), and the hydraulic pressure adjustment valve SLFR is on the discharge port side of the pump 7 (upstream side in the brake fluid flow direction in the pipe line J1). Respectively. A pipe line J <b> 2 arranged in parallel to the pump 8 connects the upstream side and the downstream side of the pump 8, bypassing the pump 8. In the present embodiment, the pipe line J2 has one end connected to the upstream side of the pump 8 of the individual pipe line H2, and the other end connected to the downstream side of the pump 8 of the individual pipe line H2. Further, a hydraulic pressure adjusting valve SLRL is provided in the middle of the pipe line J2.

  The pipe line J3 arranged in parallel to the pump 9 connects the upstream side and the downstream side of the pump 9 so as to bypass the pump 9. In the present embodiment, the pipe line J3 has one end connected to the upstream side of the pump 9 of the individual pipe line I3 and the other end connected to the pipe line G located on the downstream side of the pump 9. A communication valve SRC2 and a hydraulic pressure adjustment valve SLFL are provided in series in the middle of the pipe line J3. The communication valve SRC2 is on the suction port side of the pump 9 (downstream side in the brake fluid flow direction in the pipeline J3), and the hydraulic pressure adjustment valve SLFL is on the discharge port side of the pump 9 (upstream side in the brake fluid flow direction in the pipeline J3). Respectively. A pipe line J4 arranged in parallel to the pump 10 connects the upstream side and the downstream side of the pump 10 so as to bypass the pump 10. In this embodiment, the pipe line J4 has one end connected to the pipe line I located on the upstream side of the pump 10, and the other end connected to the downstream side of the pump 10 in the individual pipe line I4. A hydraulic pressure adjustment valve SLRR is provided in the middle of the pipe line J4.

  The communication valves SRC1 and SRC2 each have a solenoid and a spring that are controlled to be turned on / off, both of which are opened by electromagnetic force generated by the solenoid when supplied with a prescribed control current, This is a normally closed electromagnetic control valve that is closed when energized. The communication valves SRC1 and SRC2 that are opened can allow the brake fluid to flow from the wheel cylinders 6FR and 6FL to the reservoir tank 3f. When the solenoid is energized and the communication valves SRC1 and SRC2 are closed, the flow of brake fluid in the pipelines J1 and J3 is blocked.

  The hydraulic pressure regulating valves SLFR, SLRL, SLFL, SLRR have a linear solenoid and a spring, and are opened when the linear solenoid is in a non-energized state, and in proportion to the current supplied to the linear solenoid. It is a normally open type electromagnetic control valve in which the opening degree of the valve is adjusted. When the hydraulic pressure adjusting valves SLFR, SLRL, SLFL, and SLRR are in the open state, the brake fluid can be circulated from the wheel cylinder 6 side to the reservoir tank 3f side. When a current is applied to the linear solenoid, the valve is closed in proportion to the supplied current and the flow rate of the brake fluid decreases. Therefore, the flow amount of the brake fluid from each wheel cylinder 6 to the reservoir tank 3f can be changed by changing the opening degree of the hydraulic pressure adjusting valves SLFR, SLRL, SLFL, SLRR. It is possible to adjust the hydraulic pressure generated in

  Wheel cylinder pressure sensors 13, 14, 15, and 16 are provided downstream of the pumps 7 to 10 of the individual pipes H1, H2, I3, and I4 (between the pumps 7 to 10 and the wheel cylinder 6), respectively. ing. The wheel cylinder pressure sensors 13 to 16 can detect the brake fluid pressure in the wheel cylinders 6FR, 6RL, 6FL, and 6RR, that is, the wheel cylinder pressure. Master cylinder pressure sensors 17 and 18 are provided upstream of the master cut valves SMC1 and SMC2 in the pipelines F and G (between the master cut valves SMC1 and SMC2 and the master cylinder 3). The master cylinder pressure sensors 17 and 18 can detect the hydraulic pressure of the brake fluid in the secondary chamber 3b and the primary chamber 3a of the master cylinder 3, that is, the master cylinder pressure.

  Further, a check valve 20 is provided at the discharge port of the pump 7, and a check valve 21 is provided at the discharge port of the pump 9. The check valves 20 and 21 function to inhibit the flow of brake fluid from the wheel cylinders 6FR and 6FL to the pumps 7 and 9 respectively.

  The brake ECU 200 is a nonvolatile memory such as a CPU that executes various arithmetic processes, a ROM that stores various control programs, a RAM that is used as a work area for data storage and program execution, and a backup RAM that can retain stored contents even when the engine is stopped. A / D converter and the like for converting analog signals input from a memory, an input / output interface, various sensors, etc. into digital signals. The brake ECU 200 is electrically connected to master cut valves SMC1, SMC2, simulator cut valve SCSS, communication valves SRC1, SRC2, hydraulic pressure adjusting valves SLFR-SLRR, first motor 11, second motor 12, and the like. In addition, the brake ECU 200 can communicate with an upper hybrid ECU (not shown) and the like.

  The brake ECU 200 is electrically connected to various sensors and switches that output signals for use in control. That is, a signal indicating the wheel cylinder pressure in the wheel cylinder 6 is input from the wheel cylinder pressure sensors 13 to 16 to the brake ECU 200, and a signal indicating the pedaling force of the brake pedal 1 is input from the pedaling force sensor 2. A signal indicating the master cylinder pressure is input from 17 and 18. Further, although not shown, the brake ECU 200 receives a signal indicating the wheel speed of each wheel from a wheel speed sensor installed for each wheel, a signal indicating a yaw rate from the yaw rate sensor, and an acceleration of the vehicle from the G sensor. A signal indicating the steering angle of the steering wheel is input from the steering angle sensor.

  The brake control device 100 configured as described above includes a plurality of piping systems that generate hydraulic pressure in the wheel cylinder 6 by supplying brake fluid via a hydraulic circuit. Specifically, the brake control device 100 applies the brake fluid of the reservoir tank 3f to the wheel cylinders 6FR and 6RL via the hydraulic circuit including the pipelines C and H, the individual pipelines H1 and H2, and the pipelines J1 and J2. The brake fluid of the reservoir tank 3f is supplied to the wheel cylinders 6FL, 6RR via the first piping system for supplying the gas and the hydraulic circuit including the pipelines D, I, the individual pipelines I3, I4, and the pipelines J3, J4. And a second piping system. The brake control device 100 also supplies a brake fluid supply path for supplying the brake fluid of the master cylinder 3 which is a manual hydraulic pressure source to the wheel cylinder 6FR via the pipelines A and F, and via the pipelines B and G. And a brake fluid supply path for supplying the wheel cylinder 6FL.

  The brake control device 100 can execute brake regeneration cooperative control. The brake control device 100 receives the braking request and starts braking. The braking request is generated when a braking force is to be applied to the vehicle, for example, when the driver operates the brake pedal 1. In response to the braking request, the brake ECU 200 calculates a required braking force, and calculates a required hydraulic braking force, which is a braking force that should be generated by the brake control device 100, by subtracting the regenerative braking force from the required braking force. Here, the effective value of the braking force by regeneration is supplied to the brake control device 100 from the hybrid ECU. Then, the brake ECU 200 calculates the target hydraulic pressure of each wheel cylinder 6 based on the calculated required hydraulic braking force. The brake ECU 200 controls the opening and closing of each valve and the driving of the first motor 11 and the second motor 12 so that the wheel cylinder pressure becomes the target hydraulic pressure, so that the wheel by the first piping system and the second piping system is used. The supply of brake fluid to the cylinder 6 is controlled.

  As a result, in the brake control device 100, the brake fluid is supplied from the reservoir tank 3f to each wheel cylinder 6 and a braking force is applied to the wheels. Further, as necessary, the brake fluid is discharged from each wheel cylinder 6 through the hydraulic pressure adjustment valves SLFR, SLRL, SLFL, SLRR, and the braking force applied to the wheels is adjusted. In the present embodiment, so-called brake-by-wire braking force control is performed by the first piping system and the second piping system. The first piping system and the second piping system are provided in parallel to the brake fluid supply path from the master cylinder 3 to the wheel cylinder 6. That is, the pumps 7 to 10 are provided in parallel with the master cylinder 3 which is a manual hydraulic pressure source.

  A partition wall is provided in the reservoir tank 3f of the brake control device 100, and the brake fluid flowing in the first piping system and the brake fluid flowing in the second piping system are stored separately. Further, the hydraulic circuit of the first piping system and the hydraulic circuit of the second piping system are independent of each other. Therefore, the first piping system and the second piping system are independent from each other with respect to the brake fluid flowing through each. Therefore, even if one piping system fails, the brake fluid can be supplied to the wheel cylinder 6 connected to the other piping system by the other piping system.

  FIG. 2 is a diagram for explaining the configuration of the current supply circuit 110 that supplies current from the battery 300 to the simulator cut valve SCSS. In the brake control device 100 according to the present embodiment, the current supply circuit 110 is provided in the brake ECU 200. The current supply circuit 110 includes a plurality of systems that can control the opening and closing of the simulator cut valve SCSS. Specifically, the brake ECU 200 includes a first system 210 and a second system 220.

  The first system 210 includes a first regulator 214, a first current monitor 215, a first control unit 216, and a first switch 217. The second system 220 includes a second regulator 224, a second current monitor 225, a second control unit 226, and a second switch 227.

  The first regulator 214 and the second regulator 224 are arranged in parallel between the battery 300 and the simulator cut valve SCSS. The first regulator 214 and the second regulator 224 can control the supply current to the simulator cut valve SCSS by adjusting the ratio (duty ratio) of the on / off time of the switch.

  The first current monitor 215 and the second current monitor 225 are arranged in parallel downstream of the simulator cut valve SCSS. In other words, the first current monitor 215 and the second current monitor 225 are arranged in parallel between the simulator cut valve SCSS and the ground GND. The first current monitor 215 and the second current monitor 225 each detect a current flowing through the simulator cut valve SCSS.

  The first switch 217 is disposed between the simulator cut valve SCSS and the first current monitor 215 and can turn on / off the electrical connection between the simulator cut valve SCSS and the first current monitor 215. The second switch 227 is disposed between the simulator cut valve SCSS and the second current monitor 225 and can turn on / off the electrical connection between the simulator cut valve SCSS and the second current monitor 225.

  The first control unit 216 controls the output current of the first regulator 214 based on the current value detected by the first current monitor 215. The second controller 226 controls the output current of the second regulator 224 based on the current value detected by the second current monitor 225.

  Moreover, the brake ECU 200 includes an inter-system communication unit 230 for communicating information between the first system 210 and the second system 220. The inter-system communication unit 230 includes, for example, an information transmission / reception unit provided in the first system 210, an information transmission / reception unit provided in the second system 220, and a cable (all not shown) connecting these transmission / reception units. )including.

  The first system 210 and the second system 220 configured in this way can control the supply current to the simulator cut valve SCSS independently of each other. For example, when 1 A is required to open the simulator cut valve SCSS, the first control unit 216 and the second control unit 226 supply the current to the simulator cut valve SCSS by 0.5 A each. 214, the second regulator 224 can be controlled.

  The first system 210 also controls the supply of brake fluid through the first piping system, and the second system 220 also controls the supply of brake fluid through the second piping system. By driving the electromagnetic control valve using two systems in this way, even if an abnormality occurs in one system, the hydraulic control can be performed by the other system, and a decrease in braking force is minimized. It is configured to be

  As can be seen from FIG. 1, only one stroke simulator 4 is provided in the brake control device 100, and the simulator cut valve SCSS needs to be opened even when an abnormality occurs in one of the systems. Therefore, the current supply circuit of the simulator cut valve SCSS has a circuit configuration capable of supplying current to the simulator cut valve SCSS independently in the first system 210 and the second system 220.

  Here, in the current supply circuit 110 shown in FIG. 2, a case where an abnormality such as a failure occurs in the first regulator 214 and the current cannot be supplied will be considered. At normal times, as in the above example, the first control unit 216 and the second control unit 226 issue instructions to the first regulator 214 and the second regulator 224 to supply current to the simulator cut valve SCSS by 0.5A. It shall be. In this case, the current of 0.5 A output from the second regulator 224 flows into the first current monitor 215 and the second current monitor 225 connected in parallel after passing through the simulator cut valve SCSS. Assuming that the shunt resistance values of the first current monitor 215 and the second current monitor 225 are the same, both the first current monitor 215 and the second current monitor 225 detect 0.25A which is half of 0.5A. At this time, the second control unit 226 instructs the second regulator 224 so that the current value of the second current monitor 225 is appropriate (0.5 A), but the current value of the second current monitor 225 is 0. When 5A is reached, the monitor value of the first current monitor 215 is also 0.5A. In this way, in the current supply circuit 110, when an abnormality occurs in one regulator, both the first current monitor 215 and the second current monitor 225 are energized, so the current value is simply monitored. Thus, it cannot be determined which regulator has an abnormality. When the regulator in which the abnormality has occurred cannot be determined, the control unit continues the current control for the regulator in which the abnormality has occurred. However, such an abnormal operation is not preferable because it may induce further abnormality. Therefore, the current supply circuit 110 according to the present embodiment performs an abnormal regulator detection process as described below.

  FIG. 3 is a flowchart for explaining the abnormal regulator detection processing according to the present embodiment. First, the first control unit 216 and the second control unit 226 are arranged between the current values instructed to the first regulator 214 and the second regulator 224 and the current values detected by the first current monitor 215 and the second current monitor 225. It is determined whether or not a deviation has occurred (S10). As described above, when an abnormality occurs in one of the regulators, the current values detected by the first current monitor 215 and the second current monitor 225 are instantaneously reduced. Therefore, the first control unit 216 and the second control unit 226 It can be estimated that some abnormality has occurred in either the first regulator 214 or the second regulator 224. At this time, it cannot be determined which of the first regulator 214 and the second regulator 224 is abnormal. If there is no divergence between the command current and the detected current, the first control unit 216 and the second control unit 226 wait until a divergence occurs (N in S10).

  When there is a divergence between the command current and the detected current (Y in S10), the first control unit 216 instructs the first regulator 214 to output a predetermined first current pattern. The second control unit 226 instructs the second regulator 224 to output a predetermined second current pattern different from the first current pattern (S12).

  4A and 4B are diagrams for explaining an example of the first current pattern and the second current pattern. 4A and 4B, the vertical axis represents the instruction current from the control unit to the regulator, and the horizontal axis represents time. FIG. 4A shows a first current pattern P1 that the first controller 216 instructs the first regulator 214, and FIG. 4B shows a second current that the second controller 226 instructs the second regulator 224. A current pattern P2 is shown. As shown in FIGS. 4A and 4B, the first current pattern P1 and the second current pattern P2 are both rectangular waves but have different periods. The first current pattern P1 and the second current pattern P2 are set such that the lowest current value is equal to or greater than a predetermined valve opening current (indicated by a broken line) of the simulator cut valve SCSS.

  Returning to FIG. 3, after instructing to output the first current pattern and the second current pattern in S <b> 12, the first control unit 216 and the second control unit 226 use the first current monitor 215 and the second current monitor 225 to It is determined whether or not one current pattern P1 is detected (S14).

  When the first current pattern P1 is detected (Y in S14), the first control unit 216 and the second control unit 226 determine that the second regulator 224 is abnormal (S18). The detection of the first current pattern P1 is because the first regulator 214 is normal. Then, the second control unit 226 stops the control of the second regulator 224 (S24). Further, the second control unit 226 turns off the second switch 227 so that no current flows through the second current monitor 225.

  On the other hand, when the first current pattern P1 is not detected (N in S14), the first control unit 216 and the second control unit 226 indicate that the second current pattern P2 is the first current monitor 215 and the second current monitor 225. It is determined whether or not it has been detected (S16).

  When the second current pattern P2 is detected (Y in S16), the first control unit 216 and the second control unit 226 determine that the first regulator 214 is abnormal (S20). The second current pattern P2 is detected because the second regulator 224 is normal. Then, the first control unit 216 stops the control of the first regulator 214 (S26). The first controller 216 turns off the first switch 217 so that no current flows through the first current monitor 215.

  When the second current pattern P2 is not detected in S16 (N in S16), it is determined that which of the first regulator 214 and the second regulator 224 is abnormal is indefinite (S22). In this case, the control of the first regulator 214 and the second regulator 224 is continued (S28).

  As described above, the current supply circuit 110 according to the present embodiment can determine whether an abnormality has occurred in the first regulator 214 or the second regulator 224 that supplies current to the simulator cut valve SCSS. Then, by stopping the control of the regulator in which an abnormality has occurred, it is possible to appropriately supply current to the simulator cut valve SCSS using a normal regulator. Moreover, the occurrence of further abnormalities can be prevented.

  Further, in the current supply circuit 110, the first current pattern P1 and the second current pattern P2 used for determining an abnormal regulator are such that the lowest current value is equal to or greater than a predetermined valve opening current of the simulator cut valve SCSS. Is set. As a result, it is possible to detect an abnormal regulator while continuing to drive the simulator cut valve SCSS. Therefore, it is possible to detect an abnormal regulator without causing the driver to feel uncomfortable.

  FIG. 5 is a schematic configuration diagram of a hydraulic circuit in a brake control device according to another embodiment of the present invention. The brake control device 100 may include a hydraulic circuit as shown in FIG. In addition, the same code | symbol is attached | subjected about the structure similar to Embodiment 1, and the description and illustration are abbreviate | omitted suitably.

  As shown in FIG. 5, the brake control device 100 includes a brake pedal 1, a pedal force sensor 2, a master cylinder 3, a simulator cut valve SCSS, a stroke simulator 4, and a hydraulic actuator 400. The brake control device 100 also includes a disc brake unit including brake discs FR, RL, RR, FL and wheel cylinders 6FR, 6RL, 6RR, 6FL built in the brake caliper. Further, the brake control device 100 includes a brake ECU 200.

  One end of a brake fluid pressure control pipe 402 for the right front wheel is connected to the secondary chamber 3 b of the master cylinder 3. The other end of the brake fluid pressure control pipe 402 is connected to the wheel cylinder 6FR. One end of a brake fluid pressure control pipe 404 for the left front wheel is connected to the primary chamber 3a of the master cylinder 3. The other end of the brake fluid pressure control pipe 404 is connected to the wheel cylinder 6FL. A master cut valve SMC1 and a master cylinder pressure sensor 17 are provided in the middle of the brake fluid pressure control pipe 402, and a master cut valve SMC2 and a master cylinder pressure sensor 18 are provided in the middle of the brake fluid pressure control pipe 404. It has been.

  On the other hand, one end of a hydraulic pressure supply / discharge pipe 406 is connected to the reservoir tank 3f, and the suction port of an oil pump 410 driven by a motor 408 is connected to the other end of the hydraulic pressure supply / discharge pipe 406. ing. The discharge port of the oil pump 410 is connected to a high-pressure pipe 412, and an accumulator 414 and a relief valve 416 as a pressure accumulating portion of a hydraulic pressure source are connected to the high-pressure pipe 412. In this modification, a reciprocating pump having two or more pistons (not shown) that are reciprocally moved by a motor 408 is employed as the oil pump 410. As the accumulator 414, an accumulator 414 that converts the pressure energy of the brake fluid into pressure energy of an enclosed gas such as nitrogen is stored.

  The accumulator 414 normally stores the brake fluid that has been pressurized to a predetermined hydraulic pressure range (for example, about 14 to 21 MPa) by the oil pump 410. Further, the valve outlet of the relief valve 416 is connected to a hydraulic pressure supply / discharge pipe 406. When the pressure of the brake fluid in the accumulator 414 increases abnormally to, for example, about 25 MPa, the relief valve 416 is opened, The brake fluid is returned to the hydraulic pressure supply / discharge pipe 406. Further, the high-pressure pipe 412 is provided with an accumulator pressure sensor 415 that detects the outlet pressure of the accumulator 414, that is, the pressure of the brake fluid in the accumulator 414.

  The high-pressure pipe 412 is connected to the wheel cylinders 6FR, 6FL, 6RR, 6RL via pressure increase valves 418FR, 418FL, 418RR, 418RL (hereinafter collectively referred to as “pressure increase valve 418” as appropriate). Each booster valve 418 has a linear solenoid and a spring, and is closed when the linear solenoid is in a non-energized state. The valve opening is adjusted in proportion to the current supplied to the linear solenoid. Is a normally closed electromagnetic control valve. The pressure increasing valve 418 can increase the pressure of the wheel cylinder 6 according to the opening degree.

  Further, the wheel cylinders 6FR and 6FL are connected to a hydraulic pressure supply / discharge pipe 406 via a pressure reducing valve 420FR or 420FL, respectively. The pressure reducing valves 420FR and 420FL have a linear solenoid and a spring, and are normally closed electromagnetic control valves capable of reducing the pressure of the wheel cylinders 6FR and 6FL according to their opening degrees. On the other hand, the wheel cylinders 6RR and 6RL are connected to a hydraulic pressure supply / discharge pipe 406 via a pressure reducing valve 420RR or 420RL which is a normally open electromagnetic control valve. Hereinafter, the pressure reducing valves 420FR to 420RL are collectively referred to as “pressure reducing valve 420” as appropriate. Wheel cylinder pressure sensors 13, 14, 15, and 16 are provided in the vicinity of the wheel cylinders 6FR to 6RL.

  The brake ECU 200 is electrically connected to master cut valves SMC1, SMC2, simulator cut valve SCSS, pressure increasing valve 418, pressure reducing valve 420, motor 408, and the like. The brake ECU 200 receives signals from the wheel cylinder pressure sensors 13 to 16, the pedal force sensor 2, the master cylinder pressure sensors 17 and 18, and the accumulator pressure sensor 415.

  The brake control device 100 configured as described above can execute brake regeneration cooperative control. The brake control device 100 receives a braking request and calculates a required braking force and a required hydraulic braking force. The brake ECU 200 calculates the target hydraulic pressure of each wheel cylinder 6 based on the calculated required hydraulic braking force, and supplies it to the pressure increasing valve 418 and the pressure reducing valve 420 by a feedback control law so that the wheel cylinder pressure becomes the target hydraulic pressure. The value of the control current to be determined is determined. As a result, in the brake control device 100, brake fluid is supplied from the accumulator 414 to each wheel cylinder 6 via each pressure increasing valve 418, and braking force is applied to the wheels. Further, brake fluid is discharged from each wheel cylinder 6 through the pressure reducing valve 420 as necessary, and the braking force applied to the wheel is adjusted.

  On the other hand, at this time, master cut valves SMC1 and SMC2 are closed, and simulator cut valve SCSS is opened. Therefore, the brake fluid sent from the master cylinder 3 when the driver depresses the brake pedal 1 flows into the stroke simulator 4 through the simulator cut valve SCSS. Further, when the accumulator pressure is equal to or lower than the lower limit value of the preset setting range, current is supplied to the motor 408 by the brake ECU 200, and the oil pump 410 is driven to increase the accumulator pressure. When the accumulator pressure enters the set range and reaches the upper limit value due to this pressure increase, power supply to the motor 408 is stopped.

  The present invention has been described above based on the embodiment. It should be understood by those skilled in the art that these embodiments are exemplifications, and that various modifications can be made to the combination of each component and each processing process, and such modifications are also within the scope of the present invention.

  In FIG. 4, a rectangular wave is illustrated as an example of the first current pattern P1 and the second current pattern P2, but a sine wave or a triangular wave may be used. In FIG. 4, the periods of the first current pattern P1 and the second current pattern P2 are different, but the amplitudes may be different. In short, the first current pattern P1 and the second current pattern P2 may be different from each other so that they can be identified.

  In the above-described embodiment, the case where the simulator cut valve SCSS is the current supply target of the current supply circuit 110 has been described. However, the current supply circuit 110 can be used for other than the simulator cut valve SCSS. For example, the current supply circuit 110 can also be applied to a normally open electromagnetic control valve that is closed by supplying current.

  SCSS simulator cut valve, 4 stroke simulator, 100 brake control device, 110 current supply circuit, 200 brake ECU, 210 first system, 214 first regulator, 215 first current monitor, 216 first control unit, 217 first switch, 220 second system, 224 second regulator, 225 second current monitor, 226 second control unit, 227 second switch, 300 battery.

Claims (4)

A current supply circuit for supplying current from a power source to a supply object,
A first regulator and a second regulator arranged in parallel between the power source and the supply object;
A first current monitor and a second current monitor arranged in parallel between the supply object and ground for detecting a current flowing through the supply object;
First control means for controlling an output current of the first regulator based on a current value detected by the first current monitor;
Second control means for controlling an output current of the second regulator based on a current value detected by the second current monitor;
An abnormality estimating means for estimating an abnormality of the first regulator and the second regulator;
When an abnormality is estimated by the abnormality estimation means, the first regulator instructs the first control means to output a predetermined first current pattern, and the second regulator is a predetermined difference different from the first current pattern. Current pattern indicating means for instructing the second control means to output a second current pattern;
Determination means for determining a regulator in which an abnormality has occurred based on current patterns detected in the first current monitor and the second current monitor;
A current supply circuit comprising: The current supply circuit supplies current to an electromagnetic control valve that opens or closes by supplying a current that is equal to or greater than a predetermined valve drive current.
2. The current supply circuit according to claim 1, wherein the first current pattern and the second current pattern are current patterns in which a lowest current value is set to be equal to or greater than the valve drive current. A brake control device that generates hydraulic pressure in a wheel cylinder by supplying brake fluid via a hydraulic pressure circuit, and applies braking force to a wheel by the hydraulic pressure,
A master cylinder that pressurizes the stored brake fluid in accordance with the operation of the brake operation member;
A stroke simulator that generates a reaction force to the operation of the brake operation member by supplying brake fluid from the master cylinder;
A simulator cut valve provided in the middle of a flow path communicating the master cylinder and the stroke simulator;
A current supply circuit for supplying current from a power source to the simulator cut valve;
With
The current supply circuit includes:
A first regulator and a second regulator arranged in parallel between the power source and the simulator cut valve;
A first current monitor and a second current monitor arranged in parallel between the simulator cut valve and ground for detecting a current flowing through the simulator cut valve;
First control means for controlling an output current of the first regulator based on a current value detected by the first current monitor;
Second control means for controlling an output current of the second regulator based on a current value detected by the second current monitor;
An abnormality estimating means for estimating an abnormality of the first regulator and the second regulator;
When an abnormality is estimated by the abnormality estimation means, the first regulator instructs the first control means to output a predetermined first current pattern, and the second regulator is a predetermined difference different from the first current pattern. Current pattern indicating means for instructing the second control means to output a second current pattern;
Determination means for determining a regulator in which an abnormality has occurred based on current patterns detected in the first current monitor and the second current monitor;
A brake control device comprising: The simulator cut valve is an electromagnetic control valve that opens or closes by supplying a current greater than or equal to a predetermined valve drive current,
The brake control device according to claim 3, wherein the first current pattern and the second current pattern are current patterns in which a lowest current value is set to be equal to or greater than the valve drive current.

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