JP2018052267A - Brake control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure the stability of giving braking force even in the case that a detection signal from detection means for detecting a traveling state of a vehicle is out of order.SOLUTION: A parking brake control device 35 has a travel state acquisition part for acquiring whether a vehicle currently travels or currently stops on the basis of a plurality of detection signals. Then, a travel state acquisition part is configured to acquire that the vehicle currently travels or currently stops in accordance with reception states of the plurality of detection signals on the basis of a determination order of a plurality of detection signals stored in advance. For example, when detection signals of wheel speed sensors 18A to 18D are out of order, it is acquired whether the vehicle currently travels or currently stops from information of an acceleration sensor 19.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a brake control device that applies a braking force to a vehicle such as an automobile.

  As a brake control device provided in a vehicle such as an automobile, one having an electric parking brake mechanism that operates based on driving of an electric motor is known (Patent Document 1). Here, Patent Literature 1 describes that an electric parking brake mechanism is operated while a vehicle is running to use the parking brake as an auxiliary brake.

JP 2013-1112017 A

  However, in Patent Document 1, when the detection signal of the wheel speed sensor becomes malfunctioning (for example, reception is impossible, unknown, abnormal output), it is impossible to acquire whether the vehicle is running or stopped as it is. there is a possibility. In this case, the operation of the electric parking brake mechanism (apply control, release control) does not match the driver's operation intention, and there is a possibility that the application of braking force will be unstable.

  An object of the present invention is to provide a brake control device capable of ensuring the stability of applying a braking force even when a detection signal from a detection means for detecting the running state of a vehicle becomes unstable. .

  In order to solve the above-described problems, a brake control device according to the present invention includes a braking member that presses a braked member that rotates with a wheel, and a pressing member that moves the braking member in a direction away from the braked member. A pressing member holding mechanism that is provided in a non-rotating part of the vehicle and holds the pressing member propelled by an electric motor, an operation request signal for holding or releasing the pressing member according to an operation instruction of a driver, and Control means for receiving detection signals from a plurality of detection means for detecting the traveling state of the vehicle, and for driving and controlling the electric motor to move the pressing member in accordance with the operation request signal and the detection signal; And the control means includes a traveling state acquisition unit that acquires whether the vehicle is traveling or stopped based on the plurality of detection signals, and the traveling state acquisition Has a structure of acquiring whether the advance on the basis of the determination order of the stored plurality of detection signals, wherein the vehicle is traveling or stopped in accordance with the reception state of the plurality of detection signals.

  The brake control device of the present invention can ensure the stability of applying the braking force even if the detection signal from the detection means for detecting the running state of the vehicle becomes unstable.

The conceptual diagram of the vehicle carrying the brake control apparatus by embodiment. The longitudinal cross-sectional view which expands and shows the disc brake with an electric parking brake function provided in the rear-wheel side in FIG. The block diagram which shows the parking brake control apparatus in FIG. 1, various vehicle-mounted control apparatuses, various sensors, and a switch. The flowchart which shows the process which acquires whether the vehicle is driving | running | working or is stopping. The characteristic line figure which shows an example of a time change when the process of the stop / travel determination mode A in FIG. 4 is performed. The characteristic line figure which shows an example of a time change when the process of the stop / travel determination mode B in FIG. 4 is performed. The characteristic line figure which shows an example of a time change when the process of the stop / travel determination mode C in FIG. 4 is performed. The characteristic line figure which shows an example of a time change when the process of the stop / travel determination mode D in FIG. 4 is performed.

  Hereinafter, the brake control device according to the embodiment will be described with reference to FIGS. 1 to 8 by taking as an example a case where the brake control device is mounted on a four-wheeled vehicle. Each step of the flowchart shown in FIG. 4 uses the notation “S”, and for example, step 1 is indicated as “S1”.

  In FIG. 1, on the lower side (road surface side) of the vehicle body 1 constituting the vehicle body, for example, a total of four front wheels 2 (FL, FR) and left and right rear wheels 3 (RL, RR). Wheels are provided. The wheels (each front wheel 2 and each rear wheel 3) together with the vehicle body 1 constitute a vehicle. The vehicle is equipped with a brake system for applying a braking force. Hereinafter, a vehicle brake system will be described.

  The front wheel 2 and the rear wheel 3 are provided with a disc rotor 4 as a braked member (rotating member) that rotates together with the respective wheels (the front wheels 2 and the rear wheels 3). The disc rotor 4 for the front wheel 2 is given a braking force by a front wheel disc brake 5 which is a hydraulic disc brake. The disc rotor 4 for the rear wheel 3 is given a braking force by a rear wheel side disc brake 6 which is a hydraulic disc brake with an electric parking brake function.

  A pair (one set) of rear wheel disc brakes 6 provided corresponding to the left and right rear wheels 3 together with a parking brake control device 35 described later constitute a brake control device. As shown in FIG. 2, the rear-wheel disc brake 6 includes, for example, a mounting member 6A called a carrier, a caliper 6B as a wheel cylinder, and a pair of brake pads 6C as braking members (friction members, friction pads). And a piston 6D as a pressing member.

  The attachment member 6 </ b> A is fixed to a non-rotating portion of the vehicle and is formed across the outer peripheral side of the disk rotor 4. The caliper 6B is provided on the mounting member 6A so that the disc rotor 4 can move in the axial direction. Each brake pad 6 </ b> C is movably attached to the attachment member 6 </ b> A and is disposed so as to be able to contact the disk rotor 4. Each brake pad 6 </ b> C presses the disk rotor 4. The piston 6D presses each brake pad 6C toward the disc rotor 4. That is, the piston 6 </ b> D moves each brake pad 6 </ b> C in a direction to be separated from and in contact with the disk rotor 4.

  In this case, the caliper 6B propels the brake pad 6C with the piston 6D by supplying (adding) hydraulic pressure (brake hydraulic pressure) to the cylinder 6B1 based on an operation of a brake pedal 9 described later. At this time, each brake pad 6C is pressed against both surfaces of the disc rotor 4 by the claw portion 6B2 of the caliper 6B and the piston 6D. As a result, a braking force is applied to the rear wheel 3 that rotates together with the disk rotor 4.

  Further, the rear wheel disc brake 6 is provided with an electric actuator 7 and a pressing member holding mechanism 8. The electric actuator 7 includes an electric motor 7A as an electric motor, a speed reduction mechanism (not shown) for reducing the rotation of the electric motor 7A, and the like. The electric motor 7A serves as a drive source for propelling the piston 6D. The pressing member holding mechanism 8 is a holding mechanism that holds the pressing force of the brake pad 6C. That is, the pressing member holding mechanism 8 is provided in the caliper 6B that is a non-rotating part of the vehicle, converts the rotation of the electric motor 7A into the axial displacement of the piston 6D, and is driven by the electric motor 7A. Is held in the axial position that propelled. The pressing member holding mechanism 8 is configured as a rotation / linear motion conversion mechanism such as a spindle nut mechanism, for example.

  Each rear wheel side disc brake 6 propels the piston 6D with the brake fluid pressure generated based on the operation of the brake pedal 9, etc., and presses the disc rotor 4 with the brake pad 6C, thereby extending the wheel (rear wheel 3). The braking force is applied to the vehicle. In addition, as will be described later, each rear wheel disc brake 6 causes the electric motor 7A to move the piston 6D through the pressing member holding mechanism 8 in response to an operation request based on a signal from the parking brake switch 34 or the like. Propulsion and braking force (parking brake or auxiliary brake) is applied to the vehicle.

  That is, each rear wheel side disc brake 6 as a brake mechanism (brake device) propels the piston 6D by the electric motor 7A in response to a parking brake request signal (apply request signal) which is an apply request for applying the parking brake. Thus, it is possible to maintain braking of the vehicle. At the same time, each rear wheel side disc brake 6 brakes the vehicle by supplying hydraulic pressure from a hydraulic pressure source (master cylinder 12, which will be described later, and if necessary, hydraulic pressure supply device 15) in response to operation of the brake pedal 9. It is possible.

  Thus, each rear wheel side disc brake 6 has a pressing member holding mechanism 8 that presses the brake pad 6C against the disc rotor 4 by the electric motor 7A and holds the pressing force of the brake pad 6C. On this basis, each rear wheel disc brake 6 is configured to be able to press the brake pad 6C against the disc rotor 4 by a hydraulic pressure applied separately from the pressing by the electric motor 7A.

  On the other hand, a pair (a set) of front wheel disc brakes 5 provided corresponding to the left and right front wheels 2 are configured in substantially the same manner as the rear wheel disc brake 6 except for a mechanism related to the operation of the parking brake. Has been. That is, as shown in FIG. 1, each front wheel side disc brake 5 includes an attachment member (not shown), a caliper 5A, a brake pad (not shown), a piston 5B, etc. The electric actuator 7 (electric motor 7A) for performing the release, the pressing member holding mechanism 8 and the like are not provided. However, the front wheel side disc brake 5 propels the piston 5B by the hydraulic pressure generated based on the operation of the brake pedal 9, etc., and applies braking force to the wheel (front wheel 2) and thus to the vehicle. The same as the disc brake 6.

  The front wheel side disc brake 5 may be a disc brake with an electric parking brake function, similarly to the rear wheel side disc brake 6. In the embodiment, a hydraulic disc brake 6 having an electric motor 7A is used as a brake mechanism (parking brake mechanism). However, the present invention is not limited to this, and the brake mechanism is, for example, a disc brake having an electric drum type parking brake, a cable puller type parking brake mechanism that applies a parking brake by pulling a cable with an electric motor, and the like. Also good. That is, the brake mechanism presses (promotes) the friction member (pad, shoe) against the rotating member (rotor, drum) based on the drive of the electric motor (electric actuator), and holds and releases the pressing force. If it is the structure which can be performed, various electric parking brake mechanisms can be used.

  A brake pedal 9 is provided on the front board side of the vehicle body 1. The brake pedal 9 is depressed by the driver during the braking operation of the vehicle. Based on this operation, the disc brakes 5 and 6 are applied and released as a service brake (service brake). The brake pedal 9 is provided with a brake switch 10 that detects whether or not the brake pedal 9 such as a brake lamp switch or a pedal switch is depressed (whether or not the brake operation is performed). Further, the brake pedal 9 is also provided with a brake operation detection sensor (not shown) for detecting a depression operation amount (brake operation amount) of the brake pedal 9 such as a pedal stroke sensor and a pedal depression force sensor as necessary. Yes.

  As shown in FIG. 3, the brake switch 10 is connected to a BCM 23 described later. The brake switch 10 detects the presence or absence of a brake operation and outputs a detection signal to the BCM 23. The BCM 23 outputs a detection signal (presence / absence of brake operation) of the brake switch 10 to various ECUs (for example, the ESC control device 17, the parking brake control device 35, etc.) via the vehicle data bus 20. The brake operation detection sensor (brake sensor) is connected to the ESC control device 17. The brake operation detection sensor detects a brake operation amount and outputs a detection signal to the ESC control device 17. The ESC control device 17 outputs a detection signal (brake operation amount) of the brake operation detection sensor to various ECUs (for example, the parking brake control device 35) via the vehicle data bus 20.

  The depression operation of the brake pedal 9 is transmitted via the booster 11 to the master cylinder 12 that functions as a hydraulic pressure source. The booster 11 is configured as a negative pressure booster (atmospheric pressure booster) or an electric booster (electric booster) provided between the brake pedal 9 and the master cylinder 12, and a pedaling force when the brake pedal 9 is depressed. Is transmitted to the master cylinder 12.

  At this time, the master cylinder 12 generates hydraulic pressure by the brake fluid supplied (supplemented) from the master reservoir 13. The master reservoir 13 is composed of a hydraulic fluid tank that stores brake fluid. The mechanism for generating the hydraulic pressure by the brake pedal 9 is not limited to the above configuration, and a mechanism for generating the hydraulic pressure in response to the operation of the brake pedal 9, for example, a brake-by-wire mechanism or the like may be used. .

  The hydraulic pressure generated in the master cylinder 12 is, for example, a hydraulic pressure supply device 15 (as a vehicle posture adjusting device) that adjusts the braking force applied to the wheels 2 and 3 via a pair of cylinder-side hydraulic pipes 14A and 14B. (Hereinafter referred to as ESC 15). The ESC 15 is disposed between each of the disc brakes 5 and 6 and the master cylinder 12, and distributes the hydraulic pressure from the master cylinder 12 to each of the disc brakes 5 and 6 via the brake side piping portions 16A, 16B, 16C, and 16D. To do. Thereby, a braking force is applied to each of the wheels (each front wheel 2 and each rear wheel 3) independently of each other. In this case, the ESC 15 can supply the hydraulic pressure to each of the disc brakes 5 and 6, that is, increase the hydraulic pressure of each of the disc brakes 5 and 6 even in a mode that does not follow the operation amount of the brake pedal 9.

  For this purpose, the ESC 15 has a dedicated control device constituted by, for example, a microcomputer or the like, that is, an ESC control device 17 called a hydraulic pressure supply device control unit. The ESC control device 17 performs drive control for opening and closing each control valve (not shown) of the ESC 15 and rotating and stopping an electric motor (not shown) for the hydraulic pump. Thereby, the ESC control device 17 performs control to increase, reduce or hold the brake fluid pressure supplied to the disc brakes 5 and 6 from the brake side piping sections 16A to 16D. At this time, various brake controls such as boost control, braking force distribution control, brake assist control, antilock brake control (ABS), traction control, vehicle stabilization control (including skid prevention), slope start assist control, etc. Vehicle body posture control is executed.

  In this way, the ESC control device 17 controls the braking force by controlling the hydraulic pressure supply to the pistons 5B and 6D of the disc brakes 5 and 6. The ESC control device 17 is supplied with power from a battery 32 described later through a power supply line 33. As shown in FIGS. 1 and 3, the ESC control device 17 is connected to a vehicle data bus 20. The ESC controller 17 includes four wheel speed sensors 18A, 18B, 18C, and 18D that detect the wheel speeds (rotational speeds) of the front wheels 2 and the rear wheels 3, respectively, and acceleration, deceleration, and attitude of the vehicle. An acceleration sensor (G sensor) 19 for detecting the pressure, a M / C pressure sensor 21 for detecting the master cylinder hydraulic pressure, and a W / C pressure sensor 22 for detecting the wheel cylinder hydraulic pressure as necessary are connected. Has been.

  The vehicle data bus 20 constitutes a CAN (Controller Area Network) as a serial communication unit mounted on the vehicle body 1. A large number of electronic devices mounted on the vehicle, that is, various in-vehicle control devices (various ECUs) including the ESC control device 17, the parking brake control device 35, and the like are multiplexed within the vehicle by the vehicle data bus 20. Communicate. In this case, as vehicle information sent to the vehicle data bus 20, for example, the brake switch 10, the brake operation detection sensor, the wheel speed sensors 18A to 18D, the acceleration sensor 19, the M / C pressure sensor 21, and the W / C pressure sensor 22 are used. The information (vehicle information) by the detection signal (output signal) from is mentioned.

  Further, vehicle information sent to the vehicle data bus 20 includes, for example, an ignition switch 25, a seat belt switch 27, an engine speed sensor 29, a door lock sensor, a door open sensor, a seating sensor, a vehicle speed sensor, a steering angle sensor, an accelerator. Detection signals from operation detection sensors (accelerator sensors), throttle sensors, stereo cameras, millimeter wave radars, gradient sensors (tilt sensors), shift sensors (shift position data), pitch sensors that detect vehicle movement in the pitch direction, etc. Information (vehicle information) based on output signals) is also included.

  In addition to the ESC control device 17 and the parking brake control device 35, the vehicle data bus 20 includes control devices for various in-vehicle electrical devices (various in-vehicle control devices) such as BCM23, USM24, METER26, ECM28, CVT30, NAVI31, etc. It is connected. The parking brake control device 35 performs mutual communication of various vehicle information necessary for vehicle control with the ESC control device 17, BCM 23, USM 24, METER 26, ECM 28, CVT 30, NAVI 31, etc. via the vehicle data bus 20.

  As described above, the ESC controller 17 of the ESC 15 includes, in addition to the wheel speed sensors 18A to 18D as detection means, an acceleration sensor 19, which is another detection means, an M / C pressure sensor 21, and a W / C. A pressure sensor 22 is connected. In this case, from the ESC 15 (the ESC control device 17), the detection signals of the speeds of the wheels 2 and 3, the detection signal of the acceleration sensor 19, the detection signal of the M / C pressure sensor 21, and the detection of the W / C pressure sensor 22 are detected. A signal is output as one piece of vehicle information.

  The BCM 23 is connected to a brake switch 10 that detects the amount of depression of the brake pedal 9. From the BCM 23, a detection signal relating to ON / OFF of the brake switch 10 is output as one piece of vehicle information. Further, the BCM 23 is connected to the parking brake control device 35 via the vehicle data bus 20 and is connected via a signal line different from the vehicle data bus 20. Further, the brake switch 10 may be directly connected to the parking brake control device 35 without passing through the BCM 23.

  A key type or button type ignition switch 25 for starting or stopping the vehicle (engine) is connected to the USM 24. From the USM 24, a detection signal related to turning on and off the ignition switch 25 is output as one piece of vehicle information. The USM 24 detects a voltage change due to the operation of the ignition switch 25. Similar to the BCM 23, the USM 24 is connected to the parking brake control device 35 via the vehicle data bus 20 and is connected via a signal line different from the vehicle data bus 20. Further, the ignition switch 25 may be directly connected to the parking brake control device 35 without passing through the USM 24.

  The METER 26 is connected to a seat belt switch 27 that detects attachment / detachment (mounting / release) of a seat belt (not shown) provided in a vehicle seat. From the METER 26, a detection signal relating to wearing and releasing of the seat belt is output as one piece of vehicle information. The ECM 28 is connected to an engine speed sensor 29 that detects the speed of the engine that is a power source of the vehicle. The ECM 28 outputs a detection signal relating to the engine speed as one piece of vehicle information. An electric motor can be used as a power source for the vehicle, and both an engine and an electric motor can be used.

  The CVT 30 is, for example, a transmission that continuously changes the output rotation from the engine and transmits it to the drive wheels (each front wheel 2 and / or each rear wheel 3) side. From this CVT 30, the shift position is output as one piece of vehicle information. In addition to the CVT 30, an automatic transmission (AT) or a manual transmission (MT) can be used as the transmission.

  Furthermore, the NAVI 31 displays the current location of the vehicle from the GPS signal and map information. The NAVI 31 can determine the vehicle speed from the travel distance and time. The NAVI 31 outputs the vehicle speed to the parking brake control device 35 as one piece of vehicle information.

  The vehicle body 1 is provided with a power supply line 33 connected to a battery 32 (or a generator driven by an engine) serving as a vehicle power supply. Various in-vehicle electric devices including the ESC 15 and the parking brake control device 35 are connected to the power line 33. A parking brake switch 34 is provided in the vehicle body 1.

  A parking brake switch (PKB-SW) 34 as an operation switch is provided in the vehicle body 1 at a position near a driver's seat (not shown). The parking brake switch 34 is an operation element operated by the driver. The parking brake switch 34 generates a signal (operation request signal) corresponding to a parking brake operation request (an apply request that is a holding request, a release request that is a release request) according to the driver's operation instruction, and a parking brake control device 35. To communicate. That is, the parking brake switch 34 is an operation request signal (holding request) for applying (holding) or releasing (releasing) the piston 6D and the brake pad 6C based on the drive (rotation) of the electric motor 7A. An apply request signal serving as a signal and a release request signal serving as a release request signal are output to a parking brake control device 35 serving as a parking brake control unit (control means).

  When the driver operates the parking brake switch 34 to the braking side (apply side), that is, when there is an apply request (braking hold request) for applying a braking force to the vehicle, the parking brake switch 34 applies it. A request signal (parking brake request signal) is output. In this case, electric power for rotating the electric motor 7A to the braking side is supplied to the electric motor 7A of the rear wheel disc brake 6 via the parking brake control device 35. At this time, the pressing member holding mechanism 8 pushes (presses) the piston 6D toward the disk rotor 4 based on the rotation of the electric motor 7A, and holds the pushed piston 6D. Thus, the rear wheel disc brake 6 is in a state where a braking force as a parking brake (or auxiliary brake) is applied, that is, in an applied state (braking holding state).

  On the other hand, when the driver operates the parking brake switch 34 to the braking release side (release side), that is, when there is a release request (braking release request) for releasing the braking force of the vehicle, the parking brake switch A release request signal is output from 34. In this case, electric power for rotating the electric motor 7A in the direction opposite to the braking side is supplied to the electric motor 7A of the rear wheel side disc brake 6 via the parking brake control device 35. At this time, the pressing member holding mechanism 8 releases the holding of the piston 6D by the rotation of the electric motor 7A (releases the pressing force by the piston 6D). Thereby, the rear-wheel disc brake 6 is in a state in which the application of the braking force as the parking brake (or auxiliary brake) is released, that is, in the released state (braking release state).

  For example, when the vehicle is stopped for a predetermined time (for example, when the vehicle is decelerated during traveling, the vehicle speed sensor detects that the detection speed of the vehicle speed sensor is less than 5 km / h for a predetermined time), the engine stops. When the shift lever is operated to the P position, when the door is opened, when the seat belt is released, etc., based on the automatic apply request by the parking brake apply determination logic in the parking brake control device 35 , It can be configured to automatically give (auto-apply).

  For example, when the vehicle travels (for example, it is determined that the vehicle travels when the vehicle speed sensor detects a speed of 6 km / h or more continues for a predetermined time as the vehicle speed increases from the stop), the accelerator pedal is Based on an automatic release request by the parking brake release determination logic in the parking brake control device 35, such as when operated, when the clutch pedal is operated, or when the shift lever is operated in a position other than the P position or the N position. Thus, it can be configured to automatically release (auto release). Auto-apply and auto-release can be configured as an auxiliary function at the time of a switch failure that automatically applies or releases a braking force when the parking brake switch 34 fails.

  Further, when there is an apply request by the parking brake switch 34 during traveling of the vehicle, more specifically, a request for dynamic parking brake (dynamic apply) such as urgently using the parking brake as an auxiliary brake during traveling. Even when there is a parking brake, the parking brake control device 35 applies and releases the braking force in accordance with the operation of the parking brake switch 34. For example, the parking brake control device 35 applies a braking force while the parking brake switch 34 is operated to the braking side (while the operation to the braking side continues), and applies the braking force when the operation is completed. Is released. At this time, the parking brake control device 35 automatically applies and releases braking force (ABS control) according to the state of the wheels (each rear wheel 3), that is, whether or not the wheels are locked (slip). It can be set as the structure which performs.

  The parking brake control device 35 as a control means constitutes a brake control device together with the brake pad 6C, the piston 6D and the pressing member holding mechanism 8 of each rear wheel side disc brake 6. The parking brake control device 35 has an arithmetic circuit (CPU) 36 constituted by a microcomputer or the like, and the parking brake control device 35 is supplied with power from the battery 32 through the power supply line 33.

  The parking brake control device 35 controls the driving of the electric motor 7A of each rear wheel disc brake 6 and generates a braking force (parking brake, auxiliary brake) when the vehicle is parked or stopped (running as necessary). Let That is, the parking brake control device 35 operates (applies and releases) each rear wheel side disc brake 6 as a parking brake (auxiliary brake if necessary) by driving the left and right electric motors 7A. For this purpose, the parking brake control device 35 has an input side connected to the parking brake switch 34 and an output side connected to the electric motor 7 </ b> A of each rear wheel disc brake 6.

  The parking brake control device 35 is controlled based on the operation request (apply request, release request) by the driver's operation of the parking brake switch 34, the operation request by the parking brake apply / release determination logic, and the operation request by ABS control. The left and right disc brakes 6 are applied (held) or released (released). At this time, in the rear wheel disc brake 6, the piston 6D and the brake pad 6C are held or released by the pressing member holding mechanism 8 based on the drive of the electric motor 7A. In this way, the parking brake control device 35 determines whether the piston 6D (and thus the brake is extended) in response to the operation request signal for holding operation (apply) or release operation (release) of the piston 6D (and hence brake pad 6C). The electric motor 7A is driven and controlled to propel the pad 6C).

  Here, an operation mode in the case where the braking force is generated in each rear wheel disc brake 6 by the parking brake control device 35 will be described.

  That is, as will be described later, the parking brake control device 35 has a traveling state acquisition unit (processing of S2, S4, S6, and S7 in FIG. 4) that acquires whether the vehicle is traveling or stopped. . Then, the parking brake control device 35 performs different control depending on whether the traveling state acquisition unit is “running” or “stopped”. In other words, the parking brake control device 35 applies different operation modes (first operation mode or second operation mode) according to the traveling state of the vehicle (whether the vehicle is traveling or stopped) when the braking force is applied. Apply braking force in the operation mode. In this case, the first operation mode by the parking brake control device 35 is to press the brake pad 6C against the disc rotor 4 based on the operation request signal (apply request signal) for holding the piston 6D of each rear wheel disc brake 6. The electric motor 7A of the electric actuator 7 is driven so that the piston 6D moves in the direction of movement. In the first operation mode, the electric motor 7A is driven so that the piston 6D moves in a direction in which the brake pad 6C is separated from the disk rotor 4 based on the disappearance of the holding operation request signal (apply request signal). .

  On the other hand, in the second operation mode, the electric motor 7A is driven so as to press the brake pad 6C against the disc rotor 4 with a predetermined pressing force by the piston 6D based on the operation request signal for holding the piston 6D. The predetermined pressing force is held by the pressing member holding mechanism 8.

  The parking brake control device 35 performs control (dynamic control) in the first operation mode when the traveling state acquisition unit determines that the vehicle is traveling, and performs control in the second operation mode when the vehicle is stopped ( Static control).

  As shown in FIG. 3, the arithmetic circuit 36 of the parking brake control device 35 includes a parking brake switch 34, a vehicle data bus 20, a voltage sensor unit 38, a motor drive circuit 39, a current in addition to a memory 37 as a storage unit. A sensor unit 40 and the like are connected. From the vehicle data bus 20, various state quantities of the vehicle necessary for the control (operation) of the parking brake, that is, various vehicle information can be acquired. In this case, the parking brake control device 35 transmits a signal corresponding to ON / OFF of the brake switch 10 (signal indicating whether the brake pedal 9 is operated) and a signal corresponding to ON / OFF of the ignition switch 25 (IGN voltage, HW− In addition to being able to be acquired via the vehicle data bus 20, the IGN signal) can be acquired via a signal line different from the vehicle data bus 20.

  The vehicle information acquired from the vehicle data bus 20 may be acquired by directly connecting a sensor that detects the information to the parking brake control device 35 (the arithmetic circuit 36 thereof). In addition, the arithmetic circuit 36 of the parking brake control device 35 receives an operation request based on the above-described determination logic and ABS control from another control device (for example, the ESC control device 17) connected to the vehicle data bus 20. It may be configured. In this case, it is possible to adopt a configuration in which the parking brake apply / release determination and the ABS control by the above-described determination logic are performed by another control device, for example, the ESC control device 17, instead of the parking brake control device 35. . That is, it is possible to integrate the control content of the parking brake control device 35 into the ESC control device 17.

  The parking brake control device 35 includes a memory 37 as a storage unit including, for example, a flash memory, a ROM, a RAM, an EEPROM, and the like. The memory 37 stores the above-described parking brake apply / release determination logic and ABS control program. In addition to this, the memory 37 has a processing program for executing a processing flow shown in FIG. 4 described later, that is, a processing program for determining whether the vehicle is running or stopped in various situations. Etc. are stored.

  In the embodiment, the parking brake control device 35 is separated from the ESC control device 17. However, the parking brake control device 35 may be configured integrally with the ESC control device 17. In addition, the parking brake control device 35 controls the two rear wheel disc brakes 6 on the left and right, but may be provided for each of the left and right rear wheel disc brakes 6. In this case, each parking brake control device 35 can be provided integrally with the rear wheel disc brake 6.

  As shown in FIG. 3, the parking brake control device 35 includes a voltage sensor unit 38 that detects a voltage from the power supply line 33, left and right motor drive circuits 39 that respectively drive the left and right electric motors 7 </ b> A, and the left and right electric motors 7 </ b> A. The left and right current sensor sections 40 and the like for detecting the respective motor currents are incorporated. The voltage sensor unit 38, each motor drive circuit 39, and each current sensor unit 40 are connected to the arithmetic circuit 36, respectively.

  Thereby, in the arithmetic circuit 36 of the parking brake control apparatus 35, when applying or releasing, based on the change (change in current value) of the motor current of each electric motor 7A detected by each current sensor unit 40, The corresponding contact / separation between the disc rotor 4 and the brake pad 6C, the determination of stopping the driving of the electric motor 7A (the determination of the completion of application, the determination of the completion of release), and the like can be performed.

  By the way, in the structure described in the above-mentioned patent document 1, when the detection signal of the wheel speed sensor becomes malfunctioning (for example, reception is impossible, unknown, abnormal output), the vehicle is running or stopped as it is. You may not be able to get it. On the other hand, in the embodiment, even if the detection signal becomes unsatisfactory, acquisition of whether the vehicle is running or stopped can be continued according to the unsatisfactory situation at that time. For this reason, in the embodiment, the parking brake control device 35 includes a plurality of detection means for detecting the running state of the vehicle in addition to the operation request signal for holding (applying) or releasing (release) the parking brake switch 34. The detection signal from is received. The parking brake control device 35 drives and controls the electric motor 7A according to the operation request signal and the detection signal.

  In this case, as detection signals of the plurality of detection means, in addition to the detection signals of the wheel speed sensors 18A to 18D provided in the ESC 15 (wheel speed signals that become the detection signals of the speeds of the wheels 2 and 3), the ESC 15 A detection signal (acceleration signal) of the acceleration sensor 19 as another detection means provided, a detection signal (M / C pressure signal) of the M / C pressure sensor 21, and a detection signal (W / C of the W / C pressure sensor 22) Pressure signal). Further, as detection signals of the plurality of detection means, a detection signal (engine speed signal) of an engine speed sensor 29 provided (connected) to the ECM 28, a detection signal (shift position signal) of a shift position of the CVT 30, Detection signal (seat belt signal) of the seat belt switch 27 provided (connected) to the METER 26, detection signal (IGN signal) of the ignition switch 25 provided (connected) to the USM 24, and provided to the BCM 23 ( Detection signal (brake signal) of the brake switch 10 connected), detection signal (IGN signal) of the ignition switch 25 directly connected to the parking brake control device 35, detection signal (brake signal) of the brake switch 10 It is done.

  And the parking brake control apparatus 35 has a driving | running | working state acquisition part (process of FIG. 4) which acquires whether the vehicle is drive | working or is stopped based on a some detection signal. In this case, the traveling state acquisition unit acquires whether the vehicle is traveling or stopped according to the reception states of the plurality of detection signals based on the determination orders (priority orders) of the plurality of detection signals stored in advance. . Therefore, a plurality of acquisition methods (determination method, estimation method) are illustrated in order from the highest determination order.

  The basic (normal) acquisition method determines (acquires) whether the vehicle is running or stopped based on the detection signals of the four wheel speed sensors 18A, 18B, 18C, 18D.

  When at least one of the four wheel speed sensors 18A, 18B, 18C, and 18D is normal, the vehicle is running or stopped based on the detection signal of the normal wheel speed sensor. Determine whether.

  Next, in an emergency in which none of the wheel speed sensors 18A, 18B, 18C, 18D can be used, that is, when the detection signals of the speeds of the wheels 2, 3 are malfunctioning (for example, reception is impossible, unknown, abnormal output). Acquires vehicle information from other than the wheel speed sensors 18A to 18D, estimates the vehicle speed from this information, and determines whether the vehicle is running or stopped.

  The first vehicle speed estimation method is the following vehicle detected by the acceleration sensor 19 from the vehicle speed before (immediately before) the detection signals of the speeds of the wheels 2 and 3 (from the wheel speed sensors 18A to 18D) malfunction. The vehicle speed after malfunction is estimated using the acceleration of. In this case, the malfunction of the detection signal of each wheel speed means that the signal cannot be received from each wheel speed sensor 18A to 18D, or the signal cannot be recognized, and an abnormal signal is output from each wheel speed sensor 18A to 18D. Including cases.

  In the second vehicle speed estimation method, the vehicle speed is reduced by the subsequent pressure detected by the M / C pressure sensor 21 and the W / C pressure sensor 22 from the vehicle speed before (precedingly before) the detection signal of each wheel speed becomes unstable. Obtain the speed and estimate the vehicle speed after failure.

  The third vehicle speed estimation method estimates the vehicle speed using the engine speed detected by the engine speed sensor 29 and the shift position of the CVT 30, that is, the transmission gear ratio. Specifically, the vehicle speed can be calculated by the following equation (1).

  In the above formula 1, the diameter dimension of the drive wheel and the final reduction ratio are fixed values specific to the vehicle. On the other hand, for the transmission gear ratio, a fixed value unique to the vehicle corresponding to the acquired shift position is selected and used. In this case, when the shift position is the N position (neutral range), the vehicle speed cannot be calculated. However, even when the shift position is the N position, the vehicle speed can be estimated by grasping whether the acceleration sensor 19 is in the acceleration state, the deceleration state, or the holding state.

  In the fourth vehicle speed estimation method, when the vehicle speed can be obtained by the NAVI 31 mounted on the vehicle, the vehicle speed is not estimated but the vehicle speed obtained from the NAVI 31 is used. In the fifth vehicle speed estimation method, when the rotation speed from the transmission of the engine can be obtained, the vehicle speed may be estimated using this. In the first vehicle speed estimation method to the fifth vehicle speed estimation method, the determination order may be changed. In other words, the estimation methods with higher reliability can be used in order according to the type and specification of the vehicle.

  In any case, in the embodiment, when the traveling state acquisition unit of the parking brake control device 35 can receive the detection signals of the wheels 2 and 3, that is, the detection signals (wheel speed signals) of the wheel speed sensors 18A to 18D. Acquires whether the vehicle is running or stopped based on this detection signal (wheel speed signal) (processing of S2 in FIG. 4).

  When the detection signals (wheel speed signals) of the speeds of the wheels 2 and 3 are malfunctioning, the traveling state acquisition unit of the parking brake control device 35 is provided with other detection means (acceleration sensor 19, M / C) provided in the ESC 15. Information relating to acceleration / deceleration of the vehicle among detection signals (acceleration signal, M / C pressure signal, W / C pressure signal) of the pressure sensor 21 and the W / C pressure sensor 22, for example, an acceleration signal directly corresponding to acceleration / deceleration From this, it is acquired whether the vehicle is running or stopped (the process of S4 in FIG. 4).

  The traveling state acquisition unit of the parking brake control device 35 detects the detection signals (wheel speed signals, acceleration signals, M / C) from the ESC 15 when the detection signals (wheel speed signals) of the wheels 2 and 3 are malfunctioning. When the pressure signal or the W / C pressure signal is not good, it is acquired whether the vehicle is running or stopped based on the detection signal related to the engine speed and the detection signal related to the shift position (FIG. 4). Processing in S4 and S6).

  The traveling state acquisition unit of the parking brake control device 35 includes a detection signal related to the engine speed, a detection signal related to the shift position, a detection signal related to seat belt attachment and release, a detection signal related to turning on and off the ignition switch 25, Whether the vehicle is running or stopped is acquired based on the detection signal regarding on and off of the brake switch 10 (processing of S6 in FIG. 4). Such a control of the parking brake control device 35, that is, a process of acquiring whether the vehicle is running or stopped according to the reception states of a plurality of detection signals (the process of FIG. 4) will be described in detail later. .

  Further, the parking brake control device 35 generates an electric motor based on the result acquired by the traveling state acquisition unit (that is, whether the vehicle is traveling or stopped) and the operation request signal for the parking brake switch 34. 7A is driven. At this time, the parking brake control device 35 performs the control in the first operation mode when receiving the operation request signal (apply request signal) of the parking brake switch 34 when the traveling state acquisition unit determines that the vehicle is traveling. The electric motor 7A is driven). On the other hand, the parking brake control device 35 performs control in the second operation mode upon receiving an operation request signal (apply request signal) for the parking brake switch 34 when the traveling state acquisition unit determines that the vehicle is stopped. The motor 7A is driven).

  The brake system for a four-wheeled vehicle according to the embodiment has the above-described configuration. Next, the operation thereof will be described.

  When the driver of the vehicle depresses the brake pedal 9, the depression force is transmitted to the master cylinder 12 via the booster 11, and brake fluid pressure is generated by the master cylinder 12. The brake hydraulic pressure generated in the master cylinder 12 is distributed to the disc brakes 5 and 6 via the cylinder side hydraulic pipes 14A and 14B, the ESC 15 and the brake side pipe sections 16A, 16B, 16C and 16D, and left and right front wheels. 2 and the left and right rear wheels 3 are applied with braking force, respectively.

  In this case, in each of the disc brakes 5 and 6, the pistons 5B and 6D are slidably displaced toward the brake pad 6C as the brake fluid pressure in the calipers 5A and 6B increases, and the brake pad 6C becomes the disc rotors 4 and 4 Pressed against. As a result, a braking force based on the brake fluid pressure is applied. On the other hand, when the brake operation is released, the supply of the brake fluid pressure into the calipers 5A and 6B is stopped, so that the pistons 5B and 6D are displaced so as to move away (retreat) from the disk rotors 4 and 4. As a result, the brake pad 6C is separated from the disk rotors 4 and 4, and the vehicle is returned to the non-braking state.

  Next, when the driver of the vehicle operates the parking brake switch 34 to the braking side (apply side), electric power is supplied from the parking brake control device 35 to the electric motor 7A of the rear wheel side disc brake 6, and the electric motor 7A. Is driven to rotate. In the rear wheel disc brake 6, the rotational movement of the electric motor 7A is converted into a linear movement by the pressing member holding mechanism 8, and the piston 6D propels it. Thereby, the disc rotor 4 is pressed by the brake pad 6C. At this time, the pressing member holding mechanism 8 is held in a braking state by, for example, a frictional force (holding force) by screwing. Thereby, the rear wheel side disc brake 6 is operated (applied) as a parking brake. That is, even after power supply to the electric motor 7A is stopped, the piston 6D is held at the braking position by the pressing member holding mechanism 8.

  On the other hand, when the driver operates the parking brake switch 34 to the braking release side (release side), electric power is supplied from the parking brake control device 35 to the electric motor 7A so as to reverse the motor. By this power supply, the electric motor 7A is rotated in the direction opposite to that when the parking brake is operated (during application). At this time, the holding of the braking force by the pressing member holding mechanism 8 is released, and the piston 6D can be displaced in a direction away from the disc rotor 4. As a result, the rear wheel disc brake 6 is released (released) as a parking brake.

  Next, a process performed by the arithmetic circuit 36 of the parking brake control device 35, that is, a control process for determining whether the vehicle is running or stopped will be described with reference to the flowchart of FIG. In the embodiment, the four stop / run determination modes are switched depending on whether the wheel speed is received, the wheel speed is unknown (when the detection signal of each wheel speed is malfunctioning), and the degree of failure when the wheel speed is unknown. For example, while the parking brake control device 35 is energized, the control process of FIG. 4 is repeatedly executed at a predetermined control period, that is, every predetermined time (for example, 10 ms).

  When the parking brake control device 35 is activated, the parking brake control device 35 determines whether or not there is a wheel speed normal measurement value in S1. Specifically, one of the four wheel speed sensors 18A to 18D that detects the rotational speed of the four wheels (the left and right front wheels 2 and the left and right rear wheels 3) measures the normal wheel speed. It is determined whether or not it is possible. In other words, it is determined whether or not even one normal wheel speed can be received from the ESC control device 17 via the vehicle data bus 20.

  If “YES” in S1, that is, if it is determined that any of the wheel speed sensors 18A to 18D can measure a normal wheel speed, the process proceeds to S2. In S2, it is acquired (determined) whether the vehicle is traveling or stopped in the stop / travel determination mode A.

  In this stop / run determination mode A, stop / run determination is performed based on a normal wheel speed signal acquired from the ESC control device 17 via the vehicle data bus 20. In this case, the stop / run determination can be determined from the vehicle speed by acquiring the vehicle speed using the wheel speed signal. The stop / run determination may be made directly from the wheel speed. The stop / running determination mode A will be described with reference to the characteristic diagram of FIG. 5. When an abnormality occurs in any of the wheel speed sensors 18A to 18D, the detected value from the remaining normal wheel speed sensors is used. Car stop / run determination is performed.

  In the stop / travel determination mode A, the vehicle speed is obtained from two wheel speeds among the four wheel speeds acquired from the detection values of the wheel speed sensors 18A to 18D. Further, when an abnormality occurs in one or two of the four wheel speeds, the vehicle speed is obtained by a combination of two normal wheel speeds. In addition, in the stop / run determination mode A, when a large value is set as the vehicle speed among the two normal wheel speeds, a small value is set as the vehicle speed, an average value of the two wheel speeds may be set as the vehicle speed. Conceivable. In the stop / travel determination mode A, when the calculated vehicle speed is less than a predetermined value, for example, when the vehicle speed is less than 5 km / h, it is determined that the vehicle is stopped. On the other hand, when the calculated vehicle speed is equal to or higher than a predetermined value, for example, when the vehicle speed is 6 km / h or higher, it is determined that the vehicle is running. When it is determined (determined) whether the vehicle is traveling or stopped in the stop / travel determination mode A in S2, the process returns to the start via a return, and the processes after S1 are repeated.

  If “NO” in S1, that is, if it is determined that all the wheel speed sensors 18A to 18D cannot measure the normal wheel speed, the process proceeds to S3. In S <b> 3, it is determined whether there is a communication abnormality with the ESC control device 17. The communication abnormality in this case includes, for example, an abnormality in the ESC control device 17, a disconnection between the ESC control device 17 and the vehicle data bus 20, and the like.

  In S3, “YES”, that is, it is determined that there is no communication abnormality with the ESC control device 17 (detection signals of sensors other than the wheel speed sensors 18A to 18D can be received from the ESC control device 17 via the vehicle data bus 20). If yes, go to S4. In S4, whether the vehicle is traveling or stopped is acquired by the stop / travel determination mode B. In the stop / run determination mode B, the vehicle speed is estimated using vehicle information (signals) other than the wheel speed acquired from the ESC control device 17, and the vehicle speed and other systems in the vehicle (for example, ECM28, CVT30) acquired. Stop / run determination is performed based on other vehicle information. In the stop / travel determination mode B, the stop / run determination may be performed using only vehicle information other than the wheel speed acquired from the ESC control device 17.

  The stop / run determination mode B will be described with reference to the characteristic diagram of FIG. 6. When an abnormality occurs in all of the wheel speed sensors 18A to 18D, the vehicle speed is estimated using vehicle information other than the wheel speed. The vehicle speed is acquired from the detected value from the estimated vehicle speed, and the stop / run determination is performed using the acquired vehicle speed.

  In the vehicle speed estimation method in the stop / run determination mode B, the vehicle speed is estimated from the vehicle speed before the vehicle speed becomes unknown, using the vehicle acceleration detected by the acceleration sensor 19. Further, the vehicle speed is estimated by obtaining the deceleration of the vehicle based on the pressure detected by the M / C pressure sensor 21 and the W / C pressure sensor 22 from the vehicle speed before the vehicle speed becomes unknown. A stop / run determination is performed using the estimated vehicle speed.

  In addition to this, in the stop / travel determination mode B, the engine speed detected by the engine speed sensor 29 and the shift position of the CVT 30, that is, the transmission gear ratio, are used to estimate the vehicle speed according to the above equation (1). Then, stop / run determination is performed using this vehicle speed.

  In the stop / run determination mode B, in addition to the vehicle speed estimation method described above, it can be determined that the vehicle is in a stopped state when the shift position is at the P position (parking range) or the N position (neutral range). Further, it can be determined that the vehicle is stopped when the engine speed is equal to or less than a certain value. Thus, by adding the vehicle information, the reliability of the stop / run determination can be improved. When it is determined in S4 whether the vehicle is traveling or stopped by the stop / travel determination mode B, the process returns.

  If “NO” in S3, that is, if it is determined that communication abnormality with the ESC control device 17 has occurred (all detection signals from the ESC control device 17 are malfunctioning), the process proceeds to S5. In S5, the presence / absence of communication abnormality with other systems in the vehicle (for example, BCM23, USM24, METER26, ECM28, CVT30, NAVI31) is determined. The communication abnormality in this case includes, for example, a disconnection between the vehicle data bus 20 and the parking brake control device 35.

  If “YES” in S5, that is, if it is determined that there is no communication abnormality with other systems in the vehicle (detection signals from other than the ESC control device 17 can be received via the vehicle data bus 20), the process proceeds to S6. In S6, it is acquired whether the vehicle is traveling or stopped by the stop / travel determination mode C. In the stop / run determination mode C, when communication with the ESC control device 17 is abnormal, the vehicle speed is estimated from information other than the signal acquired from the ESC control device 17 and the stop / run determination is performed.

  The stop / run determination mode C will be described using the characteristic diagram of FIG. 7. When the communication with the ESC control device 17 is not possible or when the ESC control device 17 is abnormal (failure), the output is from other than the ESC control device 17. The vehicle speed is estimated using the generated signal. In the stop / run determination mode C, the vehicle speed is estimated using the engine speed, the shift position signal, and the like. Further, in the stop / run determination mode C, when communication with the ESC control device 17 is not possible, the estimated vehicle speed includes the shift position signal of the CVT 30, the engine speed by the engine speed sensor 29, the on / off signal of the seat belt switch 27, the ignition. The stop / run determination can be performed in consideration of the on / off signal of the switch 25, the signal of the brake switch 10, and the like.

  That is, in the stop / travel determination mode C, it is determined that the vehicle is in a travel state when the estimated vehicle speed is a predetermined value (for example, 6 km / h) or more. On the other hand, when the estimated vehicle speed is less than a predetermined value (for example, 5 km / h), it is determined that the vehicle is stopped. In this case, as conditions for determining that the vehicle is in a stopped state, it is used that the shift position is the P position (parking range) or the N position (neutral range) and that the engine speed is equal to or less than a certain value. it can. Furthermore, the signal of the seat belt switch 27 when the seat belt is removed, the signal of the brake switch 10 when the stepping operation of the brake pedal 9 is released, the signal when the ignition switch 25 is turned off, and the like may be used as the stopping condition. it can. If it is determined in S6 whether the vehicle is traveling or stopped by the stop / travel determination mode C, the process returns.

  If “NO” in S5, that is, if it is determined that a communication abnormality with another system in the vehicle has occurred (the detection signal cannot be received via the vehicle data bus 20), the process proceeds to S7. In S7, whether the vehicle is traveling or stopped is acquired by the stop / travel determination mode D. The stop / running determination mode D is determined using a detection signal that the parking brake control device 35 can directly receive without passing through the vehicle data bus 20. In other words, the stop / run determination mode D uses the final stop / run determination result when the communication system (vehicle data bus 20 signal) is normal, the signal of the ignition switch 25 and the signal of the brake switch 10 to stop / run. Estimate driving conditions. Specifically, when the final stop / travel determination result is traveling, the vehicle is stopped when the stepping operation of the brake pedal 9 is released and the ignition switch 25 is turned off after a predetermined time has elapsed. If the final stop / run determination result indicates that the vehicle is stopped, the stepping operation of the brake pedal 9 is released regardless of the elapsed time, and the vehicle is stopped when the ignition switch 25 is turned off.

  In the stop / run determination mode D, for example, when the brake switch 10 is a brake operation detection sensor that can detect the operation amount of the brake pedal 9, a service brake (service brake) is used to estimate the stop / run state. The thrust generated or the generation time of the thrust can be used. That is, when the final stop / run determination result is running, it is considered that a braking force (deceleration force) sufficient to stop the vehicle is generated when the generated thrust exceeds a predetermined value. Judged as medium. Alternatively, even when the thrust generation time exceeds a predetermined value, it is determined that a deceleration force sufficient to stop the vehicle is generated, and it is determined that the vehicle is stopped. On the other hand, when the final stop / run determination result is that the vehicle is stopped, it is determined that the vehicle is stopped if the generated thrust does not decrease.

  Thus, in the present embodiment, the parking brake control device 35 acquires a traveling state acquisition unit (of S2, S4, S6, and S7 in FIG. 4) that acquires whether the vehicle is traveling or stopped based on a plurality of detection signals. Processing). In this case, the traveling state acquisition unit is configured to acquire whether the vehicle is traveling or stopped according to the reception states of the plurality of detection signals based on the determination orders of the plurality of detection signals stored in advance.

  Here, when it is not possible to acquire the traveling state of whether the vehicle is traveling or stopped, the driver's operation (apply control, release control) of each rear wheel side disc brake 6 including the electric parking brake mechanism is There is a possibility that the application of the braking force will not be stable without being consistent with the operation intention.

  On the other hand, according to the present embodiment, even if the speeds of the wheels 2 and 3, that is, the detection signals from the wheel speed sensors 18 </ b> A to 18 </ b> D are malfunctioning, the vehicle among the detection signals of the other detection means. Whether the vehicle is running or stopped can be acquired from information regarding acceleration / deceleration of the vehicle, for example, information from the acceleration sensor 19 of the ESC control device 17. Furthermore, whether the vehicle is running or stopped using information such as the brake switch 10 of the BCM 23, the ignition switch 25 of the USM 24, the seat belt switch 27 of the METER 26, the engine speed sensor 29 of the ECM 28, the CVT 30, and the NAVI 31. Can be obtained.

  Thereby, even when the detection signals of the speeds of the wheels 2 and 3 are malfunctioning, it is possible to continue the stop / run determination. As a result, when the parking brake switch 34 is operated, a braking force according to the driver's operation intention can be applied, and the operation performance (braking performance) of the parking brake can be stabilized.

  Further, the parking brake control device 35 drives the electric motor 7A in the apply direction based on the apply request signal, and drives the electric motor 7A in the release direction based on the disappearance of the apply request signal. Based on the apply request signal, there is a second operation mode in which the electric motor 7A is driven in the apply direction until a predetermined pressing force is reached, and the predetermined pressing force is held by the pressing member holding mechanism 8. . Then, the parking brake control device 35 performs control in the first operation mode when the traveling state acquisition unit determines that the vehicle is traveling, and performs control in the second operation mode when the vehicle is stopped. . Thereby, even when the electric parking brake is used as a parking brake or when it is used as an auxiliary brake in an emergency, stable operation performance can be obtained.

  In the embodiment, the case where the left and right rear wheel disc brakes 6 are disc brakes with an electric parking brake function has been described as an example. However, the present invention is not limited to this, and the left and right front wheel disc brakes 5 may be disc brakes with an electric parking brake function. Moreover, you may comprise the brake of all the wheels (all four wheels) of a front wheel and a rear wheel by the disc brake with an electric parking brake function. That is, the brake of at least a pair of wheels of the vehicle can be configured by a disc brake with an electric parking brake function.

  In the embodiment, a hydraulic disc brake 6 with an electric parking brake has been described as an example of the parking brake control device. However, the present invention is not limited to the disc brake type brake mechanism, and may be configured as a drum brake type brake mechanism. Further, various brake mechanisms can be employed, such as a drum-in disc brake in which a drum-type electric parking brake is provided on the disc brake, and a configuration in which the parking brake is held by pulling a cable with an electric motor.

  As the brake control device based on the embodiment described above, for example, the following modes can be considered.

  (1). As a first aspect, a braking member that presses a braked member that rotates together with a wheel, a pressing member that moves the braking member in a direction to move away from the braked member, and a non-rotating part of a vehicle are provided. In order to detect a pressing member holding mechanism that holds the pressing member propelled by an electric motor, an operation request signal for holding or releasing the pressing member according to an operation instruction of a driver, and a traveling state of the vehicle Control means for receiving detection signals from the plurality of detection means and driving and controlling the electric motor to move the pressing member in response to the operation request signal and the detection signal, the control means, A traveling state acquisition unit that acquires whether the vehicle is traveling or stopped based on the plurality of detection signals, and the traveling state acquisition unit is configured to store the plurality of detection signals stored in advance. Based on the constant order, the vehicle acquires whether or stopped running in accordance with the reception state of the plurality of detection signals.

  According to the first aspect, even when the detection signals cannot be received from the plurality of detection means for detecting the running state of the vehicle, the vehicle is running or stopped according to the reception state of the other detection signals. Can get.

  (2). As a second aspect, in the first aspect, the control means detects a speed detection signal of each wheel from a vehicle posture adjusting device that adjusts a braking force to each wheel of the vehicle, and the vehicle posture adjusting device. A detection signal of another detection means provided in the vehicle, wherein the traveling state acquisition unit detects the detection signal of the other detection means when the detection signal of the speed of each wheel is malfunctioning. Whether the vehicle is running or stopped is acquired from information related to acceleration / deceleration of the vehicle.

  According to the second aspect, even when the detection signals of the speeds of the wheels are malfunctioning, the traveling state acquisition unit determines that the vehicle is traveling from the information on the acceleration / deceleration of the vehicle among the detection signals of the other detection means. Or you can get what is stopped.

  (3). As a third aspect, in the second aspect, the control means further receives a detection signal related to the engine speed of the vehicle and a detection signal related to a shift position of the transmission of the vehicle. When the detection signal of the speed of each wheel is malfunctioning or when the detection signal from the vehicle attitude adjustment device is malfunctioning, the running state acquisition unit and the detection signal regarding the engine speed and the shift Whether the vehicle is running or stopped is acquired based on the detection signal related to the position.

  According to the third aspect, even when the detection signal of the speed of each wheel is malfunctioning, the traveling state acquisition unit detects that the vehicle has traveled from the information of the detection signal regarding the engine speed and the detection signal regarding the shift position of the transmission. You can get information about whether you are in or stopped.

  (4). As a fourth aspect, in the third aspect, the control means further includes a detection signal relating to mounting and release of a seat belt provided in a seat of the vehicle, and a detection signal relating to on and off of an ignition switch of the vehicle. And a detection signal related to turning on and off the brake switch of the vehicle, wherein the running state acquisition unit is a detection signal related to the rotational speed of the engine, a detection signal related to the shift position, Whether the vehicle is running or stopped based on a detection signal related to seat belt attachment and release, a detection signal related to ON / OFF of the ignition switch, and a detection signal related to ON / OFF of the brake switch To get.

  According to the fourth aspect, even when the detection signal of the speed of each wheel is malfunctioning, the traveling state acquisition unit is configured to detect the detection signal related to seat belt attachment and release, the detection signal related to the ignition switch on / off, and the brake switch. Whether the vehicle is running or stopped can be acquired from the information of the detection signal relating to turning on and off.

  (5). As a fifth aspect, in any one of the first to fourth aspects, the pressing member moves in a direction of pressing the braking member against the member to be braked based on an operation request signal for holding the pressing member. And driving the electric motor so that the pressing member moves in a direction to move the braking member away from the braked member based on the disappearance of the holding operation request signal. Based on the operation mode and an operation request signal for holding the pressing member, the electric motor is driven so that the pressing member presses the braking member against the member to be braked with a predetermined pressing force, and the predetermined pressing force is applied. A second operation mode in which the pressure is held by the pressing member holding mechanism, and the control means controls the first operation mode when the traveling state acquisition unit determines that the vehicle is traveling. Was carried out, it carries out control in the second mode of operation when it is a stopped.

  According to the fifth aspect, it is possible to obtain stable operation performance (braking performance) regardless of whether the brake is used as a parking brake or an emergency auxiliary brake.

2 Front wheels
3 Rear wheels
4 Disc rotor (braking member)
6 Rear wheel disc brake 6C Brake pad (braking member)
6D piston (pressing member)
7 Electric Actuator 7A Electric Motor 8 Pressing Member Holding Mechanism 10 Brake Switch (Detecting Means)
15 ESC (vehicle attitude adjustment device)
18A-18D Wheel speed sensor (detection means)
19 Acceleration sensor (detection means)
25 Ignition switch (detection means)
27 Seat belt switch (detection means)
29 Engine speed sensor (detection means)
30 CVT (transmission)
35 Parking brake control device (control means)
36 arithmetic circuit (running state acquisition unit)

Claims (5)

A braking member that presses a braked member that rotates with the wheel;
A pressing member that moves the braking member in a direction to be separated from and contacted with the braked member;
A pressing member holding mechanism that is provided at a non-rotating portion of the vehicle and holds the pressing member propelled by an electric motor;
An operation request signal for holding or releasing the pressing member according to a driver's operation instruction and a detection signal from a plurality of detection means for detecting a traveling state of the vehicle are received, the operation request signal and the Control means for driving and controlling the electric motor to move the pressing member in response to a detection signal,
The control means includes
A running state acquisition unit that acquires whether the vehicle is running or stopped based on the plurality of detection signals;
The traveling state acquisition unit acquires whether the vehicle is traveling or stopped according to the reception state of the plurality of detection signals based on the determination order of the plurality of detection signals stored in advance. apparatus. The brake control device according to claim 1, wherein
The control means includes
The vehicle posture adjusting device that adjusts the braking force to each wheel of the vehicle receives a detection signal of the speed of each wheel and a detection signal of another detection means provided in the vehicle posture adjusting device. And
The traveling state acquisition unit
A brake for acquiring whether the vehicle is running or stopped from information on acceleration / deceleration of the vehicle among detection signals of the other detection means when the detection signal of the speed of each wheel is malfunctioning. Control device. The brake control device according to claim 2,
The control means further includes
Receiving a detection signal relating to the rotational speed of the engine of the vehicle and a detection signal relating to a shift position of the transmission of the vehicle,
The traveling state acquisition unit
When the detection signal of the speed of each wheel is malfunctioning or when the detection signal from the vehicle attitude adjustment device is malfunctioning, based on the detection signal regarding the engine speed and the detection signal regarding the shift position, A brake control device that acquires whether the vehicle is running or stopped. The brake control device according to claim 3,
The control means further includes
Receiving a detection signal relating to mounting and release of a seat belt provided in a seat of the vehicle, a detection signal relating to on / off of an ignition switch of the vehicle, and a detection signal relating to on / off of a brake switch of the vehicle Because
The traveling state acquisition unit
A detection signal relating to the rotational speed of the engine, a detection signal relating to the shift position, a detection signal relating to attachment and release of the seat belt, a detection signal relating to ON / OFF of the ignition switch, and ON / OFF of the brake switch A brake control device that acquires whether the vehicle is running or stopped based on a detection signal. The brake control device according to any one of claims 1 to 4,
Based on the disappearance of the holding operation request signal, the electric motor is driven so that the pressing member moves in the direction of pressing the braking member against the braked member based on the operation request signal for holding the pressing member. A first operation mode for driving the electric motor so that the pressing member moves in a direction in which the braking member is separated from the braked member;
Based on an operation request signal for holding the pressing member, the electric motor is driven by the pressing member to press the braking member against the braked member with a predetermined pressing force, and the predetermined pressing force is applied to the pressing member. A second operation mode of holding by a member holding mechanism,
The control means includes
A brake control device that performs control in the first operation mode when the traveling state acquisition unit is traveling, and performs control in the second operation mode when the traveling state acquisition unit is stopped.

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