WO2020090706A1 - Braking control device - Google Patents

Braking control device Download PDF

Info

Publication number
WO2020090706A1
WO2020090706A1 PCT/JP2019/042112 JP2019042112W WO2020090706A1 WO 2020090706 A1 WO2020090706 A1 WO 2020090706A1 JP 2019042112 W JP2019042112 W JP 2019042112W WO 2020090706 A1 WO2020090706 A1 WO 2020090706A1
Authority
WO
WIPO (PCT)
Prior art keywords
braking
braking force
control
control unit
drum
Prior art date
Application number
PCT/JP2019/042112
Other languages
French (fr)
Japanese (ja)
Inventor
弘隆 武谷
啓太 中野
賢太郎 湯浅
善隆 石丸
Original Assignee
株式会社アドヴィックス
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社アドヴィックス filed Critical 株式会社アドヴィックス
Publication of WO2020090706A1 publication Critical patent/WO2020090706A1/en

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17—Using electrical or electronic regulation means to control braking
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D66/00—Arrangements for monitoring working conditions, e.g. wear, temperature

Definitions

  • the present invention relates to a braking control device.
  • An electric drum brake device is one of the brake devices provided for the wheels of a vehicle.
  • the control for the electric drum brake device is roughly divided into lock control in which the braking member is brought into contact with the inner peripheral surface of the member to be braked by positively rotating the motor to generate braking force, and reverse rotation of the motor is performed.
  • the brake drum may temporarily have a large diameter due to thermal expansion. Then, if the lock control is executed in that state to generate a predetermined braking force, an excessive braking force (clamping force) will be generated when the brake drum subsequently cools and contracts in the radial direction. There is.
  • an object of the present invention is to perform cooling control on an electric drum brake device in which the brake drum temporarily has a large diameter due to thermal expansion, and then the brake drum cools and contracts in the radial direction.
  • Another object of the present invention is to provide a braking control device capable of preventing an excessive braking force from being generated.
  • a braking control device is a braking control device for controlling an electric drum brake device provided for a plurality of wheels of a vehicle, wherein a braking member is braked by rotating a motor in the electric drum brake device.
  • the braking by the electric drum brake device is controlled by executing the lock control for increasing the braking force by making contact with the inner peripheral surface of the member and the release control for decreasing the braking force by rotating the motor.
  • a control unit for controlling.
  • the control unit acquires or estimates the temperature of the brake drum, and based on the temperature, when the brake drum subsequently cools and contracts in the radial direction.
  • a braking force adjustment control for adjusting the braking force by at least one of the lock control and the release control is executed so that the braking force does not exceed a predetermined upper limit braking force.
  • FIG. 1 is a schematic configuration diagram of a brake device that is a control target of the braking control device of the first embodiment.
  • FIG. 2 is a side view from the outside in the vehicle width direction of the brake device provided on the right rear wheel in the first embodiment.
  • FIG. 3 is a block diagram showing a functional configuration of the braking control device in the first embodiment.
  • FIG. 4 is a time chart showing changes over time of the components and the like in the first embodiment.
  • FIG. 5 is a flowchart showing a series of processes executed by the braking control device in the first embodiment.
  • FIG. 6 is a time chart showing changes over time of the components and the like in the second embodiment.
  • FIG. 7 is a graph showing the relationship between the drum temperature and the clamping force in the third embodiment.
  • FIG. 8 is a graph showing how the EPB current value changes with time during lock control and release control in the fourth embodiment.
  • FIG. 1 is a schematic configuration diagram of a brake device 100 that is a control target of the braking control device 200 (FIG. 3) of the first embodiment.
  • the brake device 100 is provided, for example, in a general four-wheel vehicle.
  • the brake device 100 is a hydraulic brake 1 configured to be able to apply a braking force (friction braking torque) to both the front wheels 2FL and 2FR and the rear wheels 2RL and 2RR.
  • the electric parking brake 2 configured to be able to apply the braking force only to the wheels 2RL and 2RR that are rear wheels.
  • the braking force generated by the hydraulic brake 1 is controlled.
  • the braking force generated by the electric parking brake 2 will be referred to as power, and will be referred to as parking braking force.
  • the hydraulic brake 1 includes a pressure generating unit 32, wheel cylinders 38FL, 38FR, 38RL and 38RR, pressure adjusting units 34FL, 34FR, 34RL and 34RR, and a return mechanism 37.
  • the pressure generator 32 is a mechanism that generates a pressure (fluid pressure) according to the operation of the brake pedal 31 by the driver of the vehicle.
  • the wheel cylinders 38FL, 38FR, 38RL, and 38RR are mechanisms that apply braking force to the wheels 2FL, 2FR, 2RL, and 2RR by pressurizing a braking member, respectively.
  • the pressure adjusting units 34FL, 34FR, 34RL and 34RR are mechanisms for adjusting the hydraulic pressure applied to the wheel cylinders 38FL, 38FR, 38RL and 38RR, respectively.
  • the reflux mechanism 37 is a mechanism that returns fluid (working fluid) as a medium for generating hydraulic pressure to the upstream side.
  • the pressure generating unit 32 includes a master cylinder 32a and a reservoir tank 32b.
  • the master cylinder 32a is pushed along with the operation (depression) of the brake pedal 31 to discharge the fluid replenished from the reservoir tank 32b to the two discharge ports.
  • These two discharge ports are respectively connected to the front side pressure adjusting section 34FR and the rear side pressure adjusting section 34RL and the front side pressure via an electromagnetic valve 33 capable of electrically switching between an open state and a closed state.
  • the adjusting portion 34FL and the rear pressure adjusting portion 34RR are connected.
  • the pressure adjusting units 34FL, 34FR, 34RL, and 34RR have electromagnetic valves 35 and 36 that can electrically switch between an open state and a closed state, respectively.
  • the solenoid valves 35 and 36 are provided between the solenoid valve 33 and the reservoir 41.
  • the solenoid valve 35 is connected to the solenoid valve 33, and the solenoid valve 36 is connected to the reservoir 41.
  • the solenoid valves 35 and 36 are opened and closed under the control of the braking control device 200 (see FIG. 3) to increase, maintain, or reduce the pressure generated in the wheel cylinders 38FL, 38FR, 38RL, and 38RR. It is possible to The wheel cylinder 38FL is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34FL, and the wheel cylinder 38FR is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34FR.
  • the wheel cylinder 38RL is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34RL, and the wheel cylinder 38RR is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34RR.
  • the reflux mechanism 37 includes a reservoir 41 and a pump 39, and a pump motor 40 that rotates the front and rear pumps 39 to transport the fluid to the upstream side.
  • One reservoir 41 and one pump 39 are provided corresponding to the combination of the pressure adjusting units 34FR and 34RL and the combination of the pressure adjusting units 34FL and 34RR.
  • the hydraulic brake 1 includes a stroke sensor 51 that can detect the operation amount (stroke) of the brake pedal 31, a pressure sensor (not shown in FIG. 1) that can detect the pressure generated in the master cylinder 32a, and the like. It is provided.
  • An EPB (Electric Parking Brake) motor 60 that is driven under the control of the braking control device 200 (see FIG. 3) is connected to each of the rear side wheel cylinders 38RL and 38RR.
  • the braking members of the wheel cylinders 38RL and 38RR on the rear side are pressurized in response to the driving of the EPB motor 60, so that the braking force is applied to the rear wheels 2RL and 2RR.
  • the rear wheel cylinders 38RL and 38RR and the two EPB motors 60 connected to these two wheel cylinders 38RL and 38RR provide a parking braking force different from the hydraulic braking force of the hydraulic brake 1. It functions as an electric parking brake 2 that can be generated.
  • the driver operates the hydraulic brake 1 to generate a hydraulic braking force (hydraulic brake operation) and the electric parking brake 2 It is possible to generate an appropriate braking force in the vehicle depending on the situation by appropriately using the operation for generating the parking braking force (the parking brake operation). For example, in the situation where the vehicle is stopped only by the hydraulic brake operation, if sufficient parking braking force is obtained by the subsequent parking brake operation, the hydraulic brake operation is released and the hydraulic braking force becomes zero. Even if it happens, the parking condition will be maintained.
  • the brake device 3RL and the brake device 3RR configured as the electric parking brake 2 will be described.
  • the brake device 3RR provided on the right rear wheel 2RR will be described as an example.
  • FIG. 2 is a side view from the outside in the vehicle width direction of the braking device 3RR provided on the right rear wheel in the first embodiment.
  • the brake device 3RR is configured as an electric drum brake device, and is housed inside a peripheral wall (not shown) of a cylindrical wheel of the right rear wheel 2RR.
  • the brake device 3RR includes two brake shoes 13L and 13T (braking members) that are separated from each other in the front and rear.
  • the two brake shoes 13L and 13T extend in an arc shape along the inner peripheral surface 12a of the cylindrical drum 12 (member to be braked. Brake drum).
  • the drum 12 rotates integrally with the right rear wheel 2RR around the rotation center C along the vehicle width direction. Then, the brake device 3RR moves the two brake shoes 13L and 13T so as to contact the inner peripheral surface 12a of the cylindrical drum 12, and the friction between the brake shoes 13L and 13T and the drum 12 causes the drum 12 and thus the right side. Braking the rear wheels 2RR.
  • the right brake shoe 13L in FIG. 2 is an example of a leading shoe
  • the left brake shoe 13T is an example of a trailing shoe.
  • the brake device 3RR includes a wheel cylinder 38RR operated by hydraulic pressure and an EPB motor 60 (see FIG. 1) operated by energization as actuators for moving the brake shoes 13L, 13T.
  • the wheel cylinder 38RR and the EPB motor 60 can move the two brake shoes 3L and 3T, respectively.
  • the wheel cylinder 38RR is used, for example, for braking during traveling
  • the EPB motor 60 is used, for example, for braking during parking.
  • the EPB motor 60 may be used for braking during traveling.
  • the brake device 3RR includes a disk-shaped back plate 14.
  • the back plate 14 is provided in a posture intersecting with the rotation center C. That is, the back plate 14 extends substantially along a direction intersecting the rotation center C, specifically, substantially along a direction orthogonal to the rotation center C.
  • the back plate 14 directly or indirectly supports each component of the brake device 3RR.
  • the back plate 14 supports components that are located outward of the back plate 14 as shown in FIG. 2 in the vehicle width direction. Further, the back plate 14 supports a component (not shown) that is located inward of the back plate 14 in the vehicle width direction.
  • the part that is supported by the back plate 14 and that is located inward in the vehicle width direction is, for example, the EPB motor 60 or a motion conversion mechanism (not (Illustration) and the like.
  • the back plate 4 is an example of a support member.
  • the cable 62 may also be referred to as an actuating member.
  • the back plate 14 is connected to a connecting member (not shown) for connecting to the vehicle body.
  • the connection member is, for example, a part of the suspension (for example, an arm, a link, a mounting member, etc.).
  • the opening 14a provided in the back plate 14 is used for coupling with the connecting member.
  • the brake device 3RR in FIG. 2 can be used for both driving wheels and non-driving wheels.
  • an axle (not shown) penetrates the opening 14b provided at the substantially center of the back plate 14.
  • the rotation center C1 is substantially parallel to the rotation center C of the right rear wheel 2RR.
  • the rotation center C1 is also referred to as a rotation support point.
  • the wheel cylinder 38RR is supported on the upper portion of the back plate 14.
  • the wheel cylinder 38RR has two pressing portions 21L and 21T that can project in the vehicle front-rear direction (left-right direction in FIG. 1).
  • the wheel cylinder 38RR causes the two pressing portions 1L and 21T to project in accordance with the pressurization of the internal pressure chamber.
  • the two protruding pressing parts 21L and 21T press the upper portions 13b of the brake shoes 13L and 13T, respectively. Due to the protrusion of the two pressing portions 21L and 21T, the two brake shoes 13L and 13T respectively rotate around the rotation center C1 and move so that the upper portions 13b are separated from each other in the vehicle front-rear direction. As a result, the two brake shoes 13L and 13T move radially outward of the center of rotation C of the right rear wheel 2RR.
  • a strip-shaped lining 13c is provided along the cylindrical surface on the outer periphery of each brake shoe 13L, 13T.
  • the two brake shoes 13L and 13T move radially outward of the center of rotation C, so that the lining 13c and the inner peripheral surface 12a of the drum 12 come into contact with each other, and the friction between the lining 13c and the inner peripheral surface 12a.
  • the drum 12 and thus the right rear wheel 2RR are braked.
  • the stroke between the non-braking position and the braking position of the brake shoes 13L, 13T is very small, for example, 1 mm or less.
  • the brake device 3RR includes a return member 15.
  • the return member 15 connects the two brake shoes 13L, 13T to the drum 12
  • the inner peripheral surface 12a of the drum 12 (braking position) is returned to a position (non-braking position) where the inner peripheral surface 12a of the drum 12 does not contact.
  • the return member 15 is, for example, an elastic member such as a coil spring, and gives a force in a direction in which the brake shoe 13L approaches the brake shoe 13T and a force in a direction in which the brake shoe 13T approaches the brake shoe 13L. That is, the return member 15 gives a force in a direction in which the two brake shoes 13L and 13T move away from the inner peripheral surface 12a of the drum 12.
  • the return member 15 is also called an urging member or an elastic member.
  • the brake device 3RR includes a moving mechanism 16 as the electric parking brake 2.
  • the movement mechanism 16 moves the two brake shoes 13L and 13T from the non-braking position to the braking position based on the operation of the driving mechanism (not shown) including the EPB motor 60 and the motion converting mechanism.
  • the moving mechanism 16 is provided outside the back plate 14 in the vehicle width direction.
  • the moving mechanism 16 includes a pressing lever 61, a cable 62, and a wheel cylinder 38RR.
  • the pressing lever 61 is provided between one of the two brake shoes 13L and 13T, for example, the left brake shoe 13T in FIG. 2 and the back plate 14, and rotates around the rotation center C2 on the brake shoe 13T. It is movably supported.
  • the rotation center C2 is located at the end of the brake shoe 13L on the opposite side (upper side in FIG. 2) of the rotation center C1 and is substantially parallel to the rotation center C1.
  • the cable 62 moves substantially along the back plate 14 so that the lower end portion 61a of the pressing lever 61 on the side far from the rotation center C2 approaches the other side, for example, in FIG. 2, the brake shoe 3L on the right side. It will be moved.
  • the operating position PL1 in which the pressing lever 61 is moved by the cable 62 is shown by a chain double-dashed line in FIG.
  • the pressing lever 61 has a protrusion 61b that comes into contact with the inner peripheral surface of the brake shoe 13T.
  • the projection 61b defines the initial position PL0 of the pressing lever 61 before it is moved by the cable 62.
  • the protrusion 61b is also referred to as an initial position setting unit.
  • the pressing portions 21L and 21T which are movable parts housed movably in the wheel cylinder 38RR, are different from the pressing lever 61 that is moved by the cable 62 and the brake shoe 13T that is connected to the pressing lever 61. It can be stretched by interposing between 13L and.
  • the connection position P1 between the pressing lever 61 and the pressing portion 21T which is a movable part is set between the rotation center C2 and the connection position P2 between the cable 62 and the pressing lever 61.
  • the brake shoe 13L rotates from the non-braking position around the rotation center C1 (arrow c) and moves to the braking position where it contacts the inner peripheral surface 12a of the drum 12.
  • the connection position P2 between the cable 62 and the pressing lever 61 corresponds to the force point
  • the rotation center C2 corresponds to the fulcrum
  • the connection position P1 between the pressing lever 61 and the pressing portions 21L and 21T that are movable parts corresponds to the action point.
  • the brake shoe 13T rotates from the non-braking position around the rotation center C1 and moves to the braking position where it contacts the inner peripheral surface 12a of the drum 12.
  • the operation of the moving mechanism 16 causes the brake shoes 13L and 13T to move from the non-braking position to the braking position.
  • the connection position P1 between the pressing lever 61 and the movable component 110 serves as a fulcrum.
  • the protrusion 61b of the pressing lever 61 contacts the inner peripheral surface of the brake shoe 13T, and the pressing lever 61 returns to the initial position.
  • the pressing portions 21L and 21T that are movable parts of the wheel cylinder 38RR are interposed between the pressing lever 61 and the brake shoes 13L and 13T when the brake device 3RR operates as the electric parking brake 2. Functions as a strut.
  • FIG. 3 is a block diagram showing a functional configuration of the braking control device 200 according to the first embodiment.
  • the braking control device 200 constitutes, for example, a part of a brake ECU (Electronic Control Unit) including hardware similar to an ordinary computer such as a processor and a memory.
  • the braking control device 200 may be integrated with other parts of the brake ECU, or may be configured separately from the other parts.
  • the braking control device 200 is configured to control the hydraulic brake 1 and the electric parking brake 2.
  • the braking control device 200 includes a detection unit 201 and a control unit 202 as a functional configuration.
  • the control unit 202 includes a hydraulic brake control unit 203 and an EPB control unit 204 (control unit).
  • These functional configurations are realized, for example, as a result of the processor of the braking control device 200 executing various programs stored in the memory. Note that part or all of these functional configurations may be realized by a dedicated circuit or the like.
  • the braking control device 200 also has a function of operating based on the output of the gradient detection sensor 3 configured as an acceleration sensor, a gyro sensor, or the like that detects the gradient of the road surface (the inclination of the vehicle in the front-rear direction).
  • the gradient detection sensor 3 configured as an acceleration sensor, a gyro sensor, or the like that detects the gradient of the road surface (the inclination of the vehicle in the front-rear direction).
  • the detection unit 201 is a driver who performs an operation (a hydraulic brake operation) for generating a hydraulic braking force on the hydraulic brake 1 or an operation (a parking brake operation) for setting a state in which the parking braking force can be generated.
  • the braking operation by is detected.
  • the hydraulic brake operation is, for example, an operation of the brake pedal 31 by the driver.
  • the parking brake operation is, for example, an operation of an EPB switch or a lever (not shown in FIG. 1) provided near the driver's seat. That is, the detection unit 201 detects the hydraulic brake operation based on the detection result of the stroke sensor 51 and the like, and detects the parking brake operation based on the electric signal output according to the operation of the EPB switch and the lever. ..
  • the hydraulic brake control unit 203 is configured to control the hydraulic braking force generated in the hydraulic brake 1. Further, the EPB control unit 204 is configured to be able to control the parking braking force generated in the electric parking brake 2.
  • the EPB control unit 204 locks the brake shoes 13L and 13T to the inner peripheral surface 12a of the drum 12 by positively rotating the EPB motor 60 to increase the braking force, and the EPB motor.
  • the braking by the electric parking brake 2 is controlled by executing the release control that reduces the braking force by rotating the 60 in the reverse direction.
  • the drum 12 may temporarily have a large diameter due to thermal expansion. Then, if the lock control is executed in that state to generate a predetermined braking force, an excessive braking force (clamping force) will be generated when the drum 12 subsequently cools and contracts in the radial direction. There is.
  • the EPB control unit 204 acquires or estimates the temperature of the drum 12 when controlling the braking by the electric parking brake 2, and based on the temperature, controls the EPB control unit when the drum 12 cools and contracts in the radial direction.
  • the braking force adjustment control for adjusting the braking force by at least one of the lock control and the release control is executed so that the power does not exceed the predetermined upper limit braking force.
  • the EPB control unit 204 can acquire the temperature information of the drum 12 from the temperature sensor.
  • the EPB control unit 204 may estimate the temperature of the drum 12 based on, for example, vehicle speed and history information of brake operation. it can. For example, it is considered that the degree of temperature rise of the drum 12 changes depending on the degree and frequency of the braking operation, and the EPB control unit 204 stores the function and map information indicating this in advance by the drum. Twelve temperatures can be estimated.
  • the braking operation is not limited to, for example, a hydraulic braking operation based on the driver's operation of the brake pedal 31 and an electric parking brake operation based on the operation of the EPB switch or lever by the driver, but also ABS (Antilock Brake System). Also includes hydraulic brake operation based on ESC (Electronic Stability Control). Further, in order to estimate the temperature of the drum 12, other information such as information on the outside air temperature obtained from an outside air temperature sensor (not shown) may be further used.
  • the EPB control unit 204 also stores drum temperature change information, which is information about the time change of the temperature of the drum 12. That is, when the temperature of the drum 12 is high, the EPB control unit 204 can estimate the temperature of the drum 12 for each subsequent elapsed time by referring to the drum temperature change information.
  • the EPB control unit 204 also stores drum thermal expansion coefficient information, which is information indicating the relationship between the temperature of the drum 12 and the thermal expansion coefficient.
  • FIG. 4 is a time chart showing changes over time of the components and the like in the first embodiment.
  • the EPB control unit 204 determines, based on the temperature of the drum 12, that the braking force is a predetermined upper limit braking force when the drum 12 subsequently cools and contracts in the radial direction. (For example, the lock control and the release control are repeatedly executed so as not to exceed the maximum clamp force at which the release operation is possible.)
  • the temperature of the drum 12 EPB state (state of the electric parking brake 2, lock, hold, release), and clamping force (braking force) are shown in chronological order from top to bottom.
  • the temperature of the drum 12 is significantly high at time t0, and then gradually decreases.
  • the EPB control unit 204 first performs lock control from time t0 to t1 to increase the clamping force to an appropriate clamping force. Next, from time t1 to t2, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t2 to time t3 to reduce the clamping force to zero.
  • the EPB control unit 204 performs lock control from time t3 to t4 to increase the clamping force to the proper clamping force.
  • the EPB control unit 204 keeps the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12.
  • the EPB control unit 204 performs release control from time t5 to time t6 to reduce the clamping force to zero.
  • the EPB control unit 204 performs lock control from time t6 to time t7 to raise the clamping force to the proper clamping force.
  • the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12.
  • the EPB control unit 204 performs release control from time t8 to time t9 to reduce the clamping force to zero.
  • the EPB control unit 204 performs lock control from time t9 to t10 to increase the clamping force to the proper clamping force. After time t10, the amount of decrease in temperature of the drum 12 is small, the diameter of the drum 12 is hardly contracted, and the proper clamping force is maintained.
  • FIG. 5 is a flowchart showing a series of processes executed by the braking control device 200 in the first embodiment.
  • step S1 the EPB control unit 204 determines whether or not to start the braking control for the electric parking brake 2. If Yes, the process proceeds to step S2, and if No, the process returns to step S1. In this step S1, for example, when there is a parking brake operation by an EPB switch or lever provided near the driver's seat, the EPB control unit 204 determines Yes.
  • step S2 the EPB control unit 204 executes lock control.
  • step S3 the EPB control unit 204 specifies (acquires or estimates) the temperature of the drum 12.
  • step S4 the EPB control unit 204 determines whether or not release control is necessary based on the temperature of the drum 12, the drum temperature change information, the drum thermal expansion coefficient information, and the like identified in step S3, and Yes. If No, the process proceeds to step S5, and if No, the process ends. In step S4, the EPB control unit 204 determines that release control is necessary if the clamp force exceeds the maximum clamp force at which the release operation can be performed unless release control is performed.
  • step S5 the EPB control unit 204 executes release control, and returns to step S2.
  • an excessive braking force is generated even when the drum 12 temporarily has a large diameter due to thermal expansion and then cools and contracts in diameter. You can choose not to.
  • the EPB control unit 204 repeatedly executes the lock control and the release control, so that it is possible to avoid the generation of an excessive braking force (clamping force) due to the diameter contraction accompanying the temperature decrease of the drum 12. Therefore, it is possible to reliably avoid a situation in which the release control cannot be executed due to insufficient starting torque of the EPB motor 60 due to an excessive clamping force.
  • lock control and the release control may be repeated for two wheels at the same time, or the timing may be shifted for each wheel. For example, if the vehicle is on a flat road surface or a road surface having a gentle slope and it is determined that the vehicle does not move even if all the braking forces of the two wheels are absent based on the output from the gradient detection sensor 3, etc. Just go.
  • the timing is shifted one wheel at a time.
  • the lock control and the release control may be repeated (while avoiding a state where all the two wheels have no braking force), or the two wheels may be simultaneously performed while the vehicle is stopped by the hydraulic braking force or the P range. Good.
  • the EPB control unit 204 does not generate the target braking force necessary for the EPB control unit 204 to maintain the stopped state of the vehicle, but the holding means (for example, the hydraulic pressure) different from the electric parking brake 2. Even if the braking force adjustment control is executed when it is determined that the vehicle stop state can be maintained by the brake 1, the drive device (transmission, etc.), the drive torque, the regenerative braking force, etc. Good.
  • the EPB control unit 204 holds the vehicle in a stopped state by a holding means different from the electric parking brake 2 even if the EPB control unit 204 does not generate the target braking force required to hold the stopped state of the vehicle.
  • the braking force adjustment control may be executed after the enabling.
  • the EPB control unit 204 determines that it is possible to maintain the stopped state of the vehicle by the braking force generated on only one of the plurality of wheels provided with the electric parking brake 2, or The braking force adjustment control may be executed for the wheels other than the one wheel after the braking force is increased so that the stopped state of the vehicle can be maintained with only one wheel.
  • the EPB control unit 204 performs release control before executing the braking force adjustment control, and estimates the heat shrinkage amount when the brake drum cools and contracts in the radial direction from the current value of the EPB motor 60. At least one of the braking force adjustment amount by the braking force adjustment control and the timing of executing the braking force adjustment control may be determined.
  • the second embodiment is the same as the first embodiment in that lock control and release control are repeated, but is different in that the clamping force is not reduced to 0 during release control.
  • FIG. 6 is a time chart showing changes over time of the components and the like in the second embodiment. Each item in FIG. 6 is the same as that in FIG. Further, as in the case of FIG. 4, the temperature of the drum 12 is significantly high at the time t20 and thereafter gradually decreases.
  • the EPB control unit 204 first performs lock control from time t20 to t21 to increase the clamping force to the proper clamping force. Next, from time t21 to t22, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t22 to time t23 to reduce the clamping force.
  • the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12.
  • the EPB control unit 204 performs release control from time t24 to time t25 to reduce the clamping force.
  • the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12.
  • the EPB control unit 204 performs release control from time t26 to time t27 to reduce the clamping force.
  • the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12.
  • the EPB control unit 204 performs release control from time t28 to time t29 to reduce the clamping force to the proper clamping force.
  • the EPB control unit 204 repeatedly executes the lock control and the release control, and unlike the first embodiment, the clamping force is set to 0 by the release control. It is possible to avoid the generation of an excessive braking force (clamping force) due to the diameter contraction due to the temperature decrease of the drum 12 without decreasing the temperature.
  • the release control does not need to reduce the clamp force to 0 so that the clamp force does not exceed the maximum clamp force at which the release operation is possible.
  • the braking force adjustment control can be executed while the vehicle stop state is reliably maintained.
  • the EPB control unit 204 determines the braking force when the drum 12 cools and contracts in the radial direction based on the temperature of the drum 12 thereafter.
  • the lock control is executed so that the target braking force required to maintain the stopped state is obtained. This will be described with reference to FIG.
  • FIG. 7 is a graph showing the relationship between the drum temperature and the clamping force in the third embodiment.
  • the vertical axis represents the clamping force (braking force) and the horizontal axis represents the drum temperature.
  • the braking force applied by the lock control may be a normal target braking force.
  • the drum temperature is DT1 or higher, the thermal expansion of the drum 12 occurs significantly, so the braking force applied by the lock control is set to be smaller than the normal target braking force as the drum temperature increases.
  • the braking force at the time of lock control is set to P1, and the braking force when the drum 12 subsequently cools and contracts in the radial direction becomes the target braking force (P2).
  • the braking force applied by the EPB control unit 204 at the time of lock control is set to be smaller as the drum temperature is higher. Generation of excessive braking force (clamping force) due to contraction can be avoided.
  • this method for example, when the vehicle is on a flat road surface or a road surface having a gentle slope, and it is determined that the vehicle does not move based on the output from the slope detection sensor 3 even if all the braking forces of the two wheels are not present. It is especially effective for
  • the EPB control unit 204 compares the EPB current value during lock control (drive current value of the EPB motor 60) with the EPB current value during release control to determine the degree of thermal expansion of the drum 12. presume. This will be described with reference to FIG.
  • FIG. 8 is a graph showing how the EPB current value changes with time during lock control and release control in the fourth embodiment.
  • the EPB control unit 204 shown in FIG. 8 shows the last EPB current value I1 (time t31) in the lock control and the EPB current value I2 (time t32) when the decrease degree becomes gentle immediately after the first inrush current in the release control.
  • the degree of thermal expansion of the drum 12 can be estimated by comparing Therefore, the EPB control unit 204 may previously store, for example, the comparison result of the EPB current value I1 and the EPB current value I2 and the information about the degree of thermal expansion of the drum 12 corresponding thereto.
  • the EPB control unit 204 first performs the lock control and then executes the release control before the possibility that the clamp force exceeds the maximum clamp force at which the release operation can be performed. Then, after that, the EPB control unit 204 estimates the degree of thermal expansion of the drum 12 by comparing the EPB current value I1 and the EPB current value I2. By doing so, the EPB control unit 204 can appropriately execute release control for weakening the clamping force according to the degree of thermal expansion of the drum 12. According to this method, in order to estimate the degree of thermal expansion of the drum 12, the vehicle speed and the history information of the brake operation are unnecessary.

Abstract

A braking control device according to an embodiment, wherein when controlling braking by an electric drum brake device, a control unit obtains or estimates the temperature of the brake drum, and performs, on the basis of the temperature, braking force adjustment control for adjusting the braking force by lock control and/or release control so that the braking force does not exceed a predetermined upper limit braking force when the brake drum cools afterwards and contracts in the radial direction.

Description

制動制御装置Braking control device
　本発明は、制動制御装置に関する。 The present invention relates to a braking control device.
　車両の車輪に対して設けられるブレーキ装置の１つに、電動ドラムブレーキ装置がある。電動ドラムブレーキ装置に対する制御には、大きく分けて、モータを正回転させることによって制動部材を被制動部材の内周面に当接させて制動力を発生させるロック制御と、モータを逆回転させることによって制動力を解除するリリース制御の２つがある。 An electric drum brake device is one of the brake devices provided for the wheels of a vehicle. The control for the electric drum brake device is roughly divided into lock control in which the braking member is brought into contact with the inner peripheral surface of the member to be braked by positively rotating the motor to generate braking force, and reverse rotation of the motor is performed. There are two release controls that release the braking force.
特開２０１６－１７６５７４号公報JP, 2016-176574, A
　電動ドラムブレーキ装置では、例えば、短時間に多くのブレーキ動作が実行されると、ブレーキドラムが熱膨張によって一時的に大径となる場合がある。そして、その状態でロック制御を実行して所定の制動力を発生させると、その後にブレーキドラムが冷却して径方向に収縮したときに、過大な制動力（クランプ力）が発生してしまうことがある。 In an electric drum brake device, for example, when many braking operations are executed in a short time, the brake drum may temporarily have a large diameter due to thermal expansion. Then, if the lock control is executed in that state to generate a predetermined braking force, an excessive braking force (clamping force) will be generated when the brake drum subsequently cools and contracts in the radial direction. There is.
　そこで、本発明の課題は、ブレーキドラムが熱膨張によって一時的に大径となった電動ドラムブレーキ装置に対して制動制御を行う場合に、その後にブレーキドラムが冷却して径方向に収縮しても過大な制動力が発生しないようにすることができる制動制御装置を提供することである。 Therefore, an object of the present invention is to perform cooling control on an electric drum brake device in which the brake drum temporarily has a large diameter due to thermal expansion, and then the brake drum cools and contracts in the radial direction. Another object of the present invention is to provide a braking control device capable of preventing an excessive braking force from being generated.
　本発明による制動制御装置は、車両の複数の車輪に対して設けられた電動ドラムブレーキ装置を制御する制動制御装置であって、前記電動ドラムブレーキ装置におけるモータを回転させることによって制動部材を被制動部材の内周面に当接させて制動力を増加させるロック制御、および、前記モータを回転させることによって前記制動力を減少させるリリース制御を実行することで、前記電動ドラムブレーキ装置による制動を制御する制御部を備える。前記制御部は、前記電動ドラムブレーキ装置による制動を制御する場合に、ブレーキドラムの温度を取得または推定し、前記温度に基いて、その後に前記ブレーキドラムが冷却して径方向に収縮したときに制動力が所定の上限制動力を超えないように、前記ロック制御、および、前記リリース制御の少なくともいずれかにより前記制動力を調整する制動力調整制御を実行する。 A braking control device according to the present invention is a braking control device for controlling an electric drum brake device provided for a plurality of wheels of a vehicle, wherein a braking member is braked by rotating a motor in the electric drum brake device. The braking by the electric drum brake device is controlled by executing the lock control for increasing the braking force by making contact with the inner peripheral surface of the member and the release control for decreasing the braking force by rotating the motor. And a control unit for controlling. When controlling the braking by the electric drum brake device, the control unit acquires or estimates the temperature of the brake drum, and based on the temperature, when the brake drum subsequently cools and contracts in the radial direction. A braking force adjustment control for adjusting the braking force by at least one of the lock control and the release control is executed so that the braking force does not exceed a predetermined upper limit braking force.
図１は、第１実施形態の制動制御装置の制御対象であるブレーキ装置の概要構成図である。FIG. 1 is a schematic configuration diagram of a brake device that is a control target of the braking control device of the first embodiment. 図２は、第１実施形態における右後輪に設けられたブレーキ装置の車幅方向外方からの側面図である。FIG. 2 is a side view from the outside in the vehicle width direction of the brake device provided on the right rear wheel in the first embodiment. 図３は、第１実施形態における制動制御装置の機能的構成を示すブロック図である。FIG. 3 is a block diagram showing a functional configuration of the braking control device in the first embodiment. 図４は、第１実施形態における各構成等の経時的変化の様子を示すタイムチャートである。FIG. 4 is a time chart showing changes over time of the components and the like in the first embodiment. 図５は、第１実施形態における制動制御装置が実行する一連の処理を示すフローチャートである。FIG. 5 is a flowchart showing a series of processes executed by the braking control device in the first embodiment. 図６は、第２実施形態における各構成等の経時的変化の様子を示すタイムチャートである。FIG. 6 is a time chart showing changes over time of the components and the like in the second embodiment. 図７は、第３実施形態におけるドラム温度とクランプ力の関係を示すグラフである。FIG. 7 is a graph showing the relationship between the drum temperature and the clamping force in the third embodiment. 図８は、第４実施形態におけるロック制御時とリリース制御時のＥＰＢ電流値の経時的変化の様子を示すグラフである。FIG. 8 is a graph showing how the EPB current value changes with time during lock control and release control in the fourth embodiment.
　以下、図面を参照して、本発明の実施形態について説明する。なお、以下に記載する実施形態の構成、ならびに当該構成によってもたらされる作用および結果（効果）は、あくまで一例であって、本発明は以下の記載内容に限定されるものではない。 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The configurations of the embodiments described below, and the actions and results (effects) provided by the configurations are merely examples, and the present invention is not limited to the contents described below.
　図１は、第１実施形態の制動制御装置２００（図３）の制御対象であるブレーキ装置１００の概要構成図である。ブレーキ装置１００は、例えば、四輪の一般的な車両に設けられる。 FIG. 1 is a schematic configuration diagram of a brake device 100 that is a control target of the braking control device 200 (FIG. 3) of the first embodiment. The brake device 100 is provided, for example, in a general four-wheel vehicle.
　ブレーキ装置１００は、前輪である車輪２ＦＬ、２ＦＲと、後輪である車輪２ＲＬ、２ＲＲと、の両方に制動力（摩擦制動トルク）を付与することが可能に構成された液圧ブレーキ１と、後輪である車輪２ＲＬ、２ＲＲのみに制動力を付与することが可能に構成された電動駐車ブレーキ２と、を備える。 The brake device 100 is a hydraulic brake 1 configured to be able to apply a braking force (friction braking torque) to both the front wheels 2FL and 2FR and the rear wheels 2RL and 2RR. The electric parking brake 2 configured to be able to apply the braking force only to the wheels 2RL and 2RR that are rear wheels.
　以下の説明においては、液圧ブレーキ１が発生する制動力と、電動駐車ブレーキ２が発生する制動力と、を区別する必要がある場合には、液圧ブレーキ１が発生する制動力を液圧制動力と表記し、電動駐車ブレーキ２が発生する制動力を駐車制動力と表記する。 In the following description, when it is necessary to distinguish between the braking force generated by the hydraulic brake 1 and the braking force generated by the electric parking brake 2, the braking force generated by the hydraulic brake 1 is controlled. The braking force generated by the electric parking brake 2 will be referred to as power, and will be referred to as parking braking force.
　液圧ブレーキ１は、圧力発生部３２と、ホイールシリンダ３８ＦＬ、３８ＦＲ、３８ＲＬおよび３８ＲＲと、圧力調整部３４ＦＬ、３４ＦＲ、３４ＲＬおよび３４ＲＲと、還流機構３７と、を備える。 The hydraulic brake 1 includes a pressure generating unit 32, wheel cylinders 38FL, 38FR, 38RL and 38RR, pressure adjusting units 34FL, 34FR, 34RL and 34RR, and a return mechanism 37.
　圧力発生部３２は、車両の運転者によるブレーキペダル３１の操作に応じた圧力（液圧）を発生させる機構である。 The pressure generator 32 is a mechanism that generates a pressure (fluid pressure) according to the operation of the brake pedal 31 by the driver of the vehicle.
　ホイールシリンダ３８ＦＬ、３８ＦＲ、３８ＲＬおよび３８ＲＲは、それぞれ、制動部材を加圧することで車輪２ＦＬ、２ＦＲ、２ＲＬ、および２ＲＲに制動力を付与する機構である。 The wheel cylinders 38FL, 38FR, 38RL, and 38RR are mechanisms that apply braking force to the wheels 2FL, 2FR, 2RL, and 2RR by pressurizing a braking member, respectively.
　圧力調整部３４ＦＬ、３４ＦＲ、３４ＲＬおよび３４ＲＲは、それぞれ、ホイールシリンダ３８ＦＬ、３８ＦＲ、３８ＲＬおよび３８ＲＲに与えられる液圧を調整する機構である。還流機構３７は、液圧を発生させる媒体としてのフルード（作動流体）を上流側へ戻す機構である。 The pressure adjusting units 34FL, 34FR, 34RL and 34RR are mechanisms for adjusting the hydraulic pressure applied to the wheel cylinders 38FL, 38FR, 38RL and 38RR, respectively. The reflux mechanism 37 is a mechanism that returns fluid (working fluid) as a medium for generating hydraulic pressure to the upstream side.
　上記構成において、圧力発生部３２は、マスタシリンダ３２ａと、リザーバタンク３２ｂと、を備える。マスタシリンダ３２ａは、ブレーキペダル３１の操作（踏み込み）に伴って押し込まれることで、リザーバタンク３２ｂから補充されるフルードを２つの吐出ポートに吐出する。これら２つの吐出ポートは、それぞれ、開状態と閉状態とを電気的に切り替え可能な電磁弁３３を介して、フロント側の圧力調整部３４ＦＲおよびリヤ側の圧力調整部３４ＲＬと、フロント側の圧力調整部３４ＦＬおよびリヤ側の圧力調整部３４ＲＲと、に接続される。 In the above configuration, the pressure generating unit 32 includes a master cylinder 32a and a reservoir tank 32b. The master cylinder 32a is pushed along with the operation (depression) of the brake pedal 31 to discharge the fluid replenished from the reservoir tank 32b to the two discharge ports. These two discharge ports are respectively connected to the front side pressure adjusting section 34FR and the rear side pressure adjusting section 34RL and the front side pressure via an electromagnetic valve 33 capable of electrically switching between an open state and a closed state. The adjusting portion 34FL and the rear pressure adjusting portion 34RR are connected.
　また、圧力調整部３４ＦＬ、３４ＦＲ、３４ＲＬ、および３４ＲＲは、それぞれ、開状態と閉状態とを電気的に切り替え可能な電磁弁３５および３６を有している。電磁弁３５および３６は、電磁弁３３と、リザーバ４１と、の間に設けられている。電磁弁３５は、電磁弁３３に接続され、電磁弁３６は、リザーバ４１に接続されている。 The pressure adjusting units 34FL, 34FR, 34RL, and 34RR have electromagnetic valves 35 and 36 that can electrically switch between an open state and a closed state, respectively. The solenoid valves 35 and 36 are provided between the solenoid valve 33 and the reservoir 41. The solenoid valve 35 is connected to the solenoid valve 33, and the solenoid valve 36 is connected to the reservoir 41.
　電磁弁３５および３６は、制動制御装置２００（図３参照）の制御に基いて開閉することで、ホイールシリンダ３８ＦＬ、３８ＦＲ、３８ＲＬおよび３８ＲＲで発生する圧力を、昇圧したり、維持したり、減圧したりすることが可能である。なお、ホイールシリンダ３８ＦＬは、圧力調整部３４ＦＬの電磁弁３５および３６の間に接続され、ホイールシリンダ３８ＦＲは、圧力調整部３４ＦＲの電磁弁３５および３６の間に接続されている。また、ホイールシリンダ３８ＲＬは、圧力調整部３４ＲＬの電磁弁３５および３６の間に接続され、ホイールシリンダ３８ＲＲは、圧力調整部３４ＲＲの電磁弁３５および３６の間に接続されている。 The solenoid valves 35 and 36 are opened and closed under the control of the braking control device 200 (see FIG. 3) to increase, maintain, or reduce the pressure generated in the wheel cylinders 38FL, 38FR, 38RL, and 38RR. It is possible to The wheel cylinder 38FL is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34FL, and the wheel cylinder 38FR is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34FR. The wheel cylinder 38RL is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34RL, and the wheel cylinder 38RR is connected between the solenoid valves 35 and 36 of the pressure adjusting unit 34RR.
　還流機構３７は、リザーバ４１およびポンプ３９と、フロント側およびリヤ側のポンプ３９を回転してフルードを上流側に輸送するポンプモータ４０と、を備える。リザーバ４１およびポンプ３９は、圧力調整部３４ＦＲおよび３４ＲＬの組み合わせと、圧力調整部３４ＦＬおよび３４ＲＲの組み合わせと、に対応してそれぞれ１つずつ設けられる。 The reflux mechanism 37 includes a reservoir 41 and a pump 39, and a pump motor 40 that rotates the front and rear pumps 39 to transport the fluid to the upstream side. One reservoir 41 and one pump 39 are provided corresponding to the combination of the pressure adjusting units 34FR and 34RL and the combination of the pressure adjusting units 34FL and 34RR.
　なお、液圧ブレーキ１には、ブレーキペダル３１の操作量（ストローク）を検出可能なストロークセンサ５１や、マスタシリンダ３２ａで発生する圧力を検出可能な圧力センサ（図１には不図示）などが設けられている。 The hydraulic brake 1 includes a stroke sensor 51 that can detect the operation amount (stroke) of the brake pedal 31, a pressure sensor (not shown in FIG. 1) that can detect the pressure generated in the master cylinder 32a, and the like. It is provided.
　リヤ側のホイールシリンダ３８ＲＬおよび３８ＲＲの各々には、制動制御装置２００（図３参照）の制御に基いて駆動するＥＰＢ（Electric　Parking　Brake）モータ６０が接続されている。これにより、リヤ側のホイールシリンダ３８ＲＬおよび３８ＲＲの制動部材がＥＰＢモータ６０の駆動に応じて加圧されることで、後輪である車輪２ＲＬおよび２ＲＲに制動力が付与される。 An EPB (Electric Parking Brake) motor 60 that is driven under the control of the braking control device 200 (see FIG. 3) is connected to each of the rear side wheel cylinders 38RL and 38RR. As a result, the braking members of the wheel cylinders 38RL and 38RR on the rear side are pressurized in response to the driving of the EPB motor 60, so that the braking force is applied to the rear wheels 2RL and 2RR.
　したがって、リヤ側のホイールシリンダ３８ＲＬおよび３８ＲＲと、これら２個のホイールシリンダ３８ＲＬおよび３８ＲＲに接続された２個のＥＰＢモータ６０とが、液圧ブレーキ１による液圧制動力とは別個の駐車制動力を発生可能な電動駐車ブレーキ２として機能する。 Therefore, the rear wheel cylinders 38RL and 38RR and the two EPB motors 60 connected to these two wheel cylinders 38RL and 38RR provide a parking braking force different from the hydraulic braking force of the hydraulic brake 1. It functions as an electric parking brake 2 that can be generated.
　なお、上記のような液圧ブレーキ１および電動駐車ブレーキ２が設けられた車両では、運転者は、液圧ブレーキ１に液圧制動力を発生させる操作（液圧ブレーキ操作）と、電動駐車ブレーキ２に駐車制動力を発生させる操作（駐車ブレーキ操作）と、を適宜使い分けることで、状況に応じて適切な制動力を車両に発生させることが可能である。例えば、液圧ブレーキ操作のみによって車両が停車状態になっている状況では、その後の駐車ブレーキ操作によって十分な駐車制動力が得られた場合、液圧ブレーキ操作が解除されて液圧制動力がゼロになったとしても、駐車状態がそのまま維持される。 In a vehicle provided with the hydraulic brake 1 and the electric parking brake 2 as described above, the driver operates the hydraulic brake 1 to generate a hydraulic braking force (hydraulic brake operation) and the electric parking brake 2 It is possible to generate an appropriate braking force in the vehicle depending on the situation by appropriately using the operation for generating the parking braking force (the parking brake operation). For example, in the situation where the vehicle is stopped only by the hydraulic brake operation, if sufficient parking braking force is obtained by the subsequent parking brake operation, the hydraulic brake operation is released and the hydraulic braking force becomes zero. Even if it happens, the parking condition will be maintained.
　ここで、電動駐車ブレーキ２として構成されたブレーキ装置３ＲＬおよびブレーキ装置３ＲＲについて説明する。この場合において、ブレーキ装置３ＲＬおよびブレーキ装置３ＲＲは、同様の構成であるので、右後輪２ＲＲに設けられたブレーキ装置３ＲＲを例として説明する。 Here, the brake device 3RL and the brake device 3RR configured as the electric parking brake 2 will be described. In this case, since the brake device 3RL and the brake device 3RR have the same configuration, the brake device 3RR provided on the right rear wheel 2RR will be described as an example.
　図２は、第１実施形態における右後輪に設けられたブレーキ装置３ＲＲの車幅方向外方からの側面図である。ブレーキ装置３ＲＲは、電動ドラムブレーキ装置として構成されており、右後輪２ＲＲの円筒状のホイールの周壁（不図示）の内側に収容されている。 FIG. 2 is a side view from the outside in the vehicle width direction of the braking device 3RR provided on the right rear wheel in the first embodiment. The brake device 3RR is configured as an electric drum brake device, and is housed inside a peripheral wall (not shown) of a cylindrical wheel of the right rear wheel 2RR.
　ブレーキ装置３ＲＲは、前後に離間した二つのブレーキシュー１３Ｌ、１３Ｔ（制動部材）を備える。二つのブレーキシュー１３Ｌ、１３Ｔは、円筒状のドラム１２（被制動部材。ブレーキドラム）の内周面１２ａに沿って円弧状に伸びている。 The brake device 3RR includes two brake shoes 13L and 13T (braking members) that are separated from each other in the front and rear. The two brake shoes 13L and 13T extend in an arc shape along the inner peripheral surface 12a of the cylindrical drum 12 (member to be braked. Brake drum).
　ドラム１２は、車幅方向に沿う回転中心Ｃ回りに、右後輪２ＲＲのホイールと一体に回転する。そして、ブレーキ装置３ＲＲは、二つのブレーキシュー１３Ｌ、１３Ｔを、円筒状のドラム１２の内周面１２ａに接触するよう移動させ、ブレーキシュー１３Ｌ、１３Ｔとドラム１２との摩擦によって、ドラム１２ひいては右後輪２ＲＲのホイールを制動する。 The drum 12 rotates integrally with the right rear wheel 2RR around the rotation center C along the vehicle width direction. Then, the brake device 3RR moves the two brake shoes 13L and 13T so as to contact the inner peripheral surface 12a of the cylindrical drum 12, and the friction between the brake shoes 13L and 13T and the drum 12 causes the drum 12 and thus the right side. Braking the rear wheels 2RR.
　なお、車両の前進時における右後輪２ＲＲのホイールの回転方向Ｒｗが図２における時計回り方向である場合、図２の右側のブレーキシュー１３Ｌが、リーディングシューの一例であり、左側のブレーキシュー１３Ｔが、トレーリングシューの一例である。 When the wheel rotation direction Rw of the right rear wheel 2RR when the vehicle is moving forward is the clockwise direction in FIG. 2, the right brake shoe 13L in FIG. 2 is an example of a leading shoe, and the left brake shoe 13T. Is an example of a trailing shoe.
　ブレーキ装置３ＲＲは、ブレーキシュー１３Ｌ、１３Ｔを動かすアクチュエータとして、油圧によって作動するホイールシリンダ３８ＲＲと、通電によって作動するＥＰＢモータ６０（図１参照）と、を備える。ホイールシリンダ３８ＲＲおよびＥＰＢモータ６０は、それぞれ、二つのブレーキシュー３Ｌ，３Ｔを動かすことができる。ホイールシリンダ３８ＲＲは、例えば、走行中の制動に用いられ、ＥＰＢモータ６０は、例えば、駐車時の制動に用いられる。なお、ＥＰＢモータ６０は、走行中の制動に用いられてもよい。 The brake device 3RR includes a wheel cylinder 38RR operated by hydraulic pressure and an EPB motor 60 (see FIG. 1) operated by energization as actuators for moving the brake shoes 13L, 13T. The wheel cylinder 38RR and the EPB motor 60 can move the two brake shoes 3L and 3T, respectively. The wheel cylinder 38RR is used, for example, for braking during traveling, and the EPB motor 60 is used, for example, for braking during parking. The EPB motor 60 may be used for braking during traveling.
　ブレーキ装置３ＲＲは、円盤状のバックプレート１４を備える。バックプレート１４は、回転中心Ｃと交差した姿勢で設けられている。すなわち、バックプレート１４は、回転中心Ｃと交差する方向に略沿って、具体的には回転中心Ｃと直交する方向に略沿って、広がっている。 The brake device 3RR includes a disk-shaped back plate 14. The back plate 14 is provided in a posture intersecting with the rotation center C. That is, the back plate 14 extends substantially along a direction intersecting the rotation center C, specifically, substantially along a direction orthogonal to the rotation center C.
　バックプレート１４は、ブレーキ装置３ＲＲの各構成部品を直接的または間接的に支持する。バックプレート１４は、図２に示されるような当該バックプレート１４よりも車幅方向外方に位置される部品を支持する。また、バックプレート１４は、当該バックプレート１４よりも車幅方向内方に位置される部品（不図示）を支持する。バックプレート１４に支持される車幅方向内方に位置される部品は、例えば、ＥＰＢモータ６０や、ＥＰＢモータ６０の回動をケーブル６２（あるいはロッド）の直動に変換する運動変換機構（不図示）等である。バックプレート４は、支持部材の一例である。また、ケーブル６２は、作動部材とも称されうる。 The back plate 14 directly or indirectly supports each component of the brake device 3RR. The back plate 14 supports components that are located outward of the back plate 14 as shown in FIG. 2 in the vehicle width direction. Further, the back plate 14 supports a component (not shown) that is located inward of the back plate 14 in the vehicle width direction. The part that is supported by the back plate 14 and that is located inward in the vehicle width direction is, for example, the EPB motor 60 or a motion conversion mechanism (not (Illustration) and the like. The back plate 4 is an example of a support member. The cable 62 may also be referred to as an actuating member.
　また、バックプレート１４は、車体との接続部材（不図示）に結合されている。接続部材は、例えば、サスペンションの一部（例えば、アーム、リンク、取付部材等）である。バックプレート１４に設けられた開口部１４ａは、接続部材との結合に用いられる。 Also, the back plate 14 is connected to a connecting member (not shown) for connecting to the vehicle body. The connection member is, for example, a part of the suspension (for example, an arm, a link, a mounting member, etc.). The opening 14a provided in the back plate 14 is used for coupling with the connecting member.
　図２のブレーキ装置３ＲＲは、駆動輪および非駆動輪のいずれにも用いることができる。ブレーキ装置３ＲＲが駆動輪に用いられる場合、バックプレート１４の略中央に設けられた開口部１４ｂを不図示の車軸が貫通することとなる。 The brake device 3RR in FIG. 2 can be used for both driving wheels and non-driving wheels. When the brake device 3RR is used for the driving wheels, an axle (not shown) penetrates the opening 14b provided at the substantially center of the back plate 14.
（ホイールシリンダによるブレーキシューの作動）
　図２に示されるように、ブレーキシュー１３Ｌ，１３Ｔの下端部１３ａは、回動中心Ｃ１回りに回動可能に、バックプレート１４に支持されている。回動中心Ｃ１は、右後輪２ＲＲのホイールの回転中心Ｃと略平行である。回動中心Ｃ１は、回動支持点とも称される。 (Brake shoe operation by wheel cylinder)
As shown in FIG. 2, the lower ends 13a of the brake shoes 13L and 13T are supported by the back plate 14 so as to be rotatable around the rotation center C1. The rotation center C1 is substantially parallel to the rotation center C of the right rear wheel 2RR. The rotation center C1 is also referred to as a rotation support point.
　ホイールシリンダ３８ＲＲは、バックプレート１４の上部に支持されている。ホイールシリンダ３８ＲＲは、車両前後方向（図１の左右方向）に突出可能な二つの押圧部２１Ｌ、２１Ｔを有する。ホイールシリンダ３８ＲＲは、内部の圧力室の与圧に応じて、二つの押圧部１Ｌ、２１Ｔを突出させる。 The wheel cylinder 38RR is supported on the upper portion of the back plate 14. The wheel cylinder 38RR has two pressing portions 21L and 21T that can project in the vehicle front-rear direction (left-right direction in FIG. 1). The wheel cylinder 38RR causes the two pressing portions 1L and 21T to project in accordance with the pressurization of the internal pressure chamber.
　突出した二つの押圧部２１Ｌ、２１Ｔは、それぞれ、ブレーキシュー１３Ｌ，１３Ｔの上部１３ｂを押す。二つの押圧部２１Ｌ、２１Ｔの突出により、二つのブレーキシュー１３Ｌ，１３Ｔは、それぞれ、回動中心Ｃ１回りに回動し、上部１３ｂ同士が車両前後方向に互いに離間するように移動する。これにより、二つのブレーキシュー１３Ｌ，１３Ｔは、右後輪２ＲＲのホイールの回転中心Ｃの径方向外方に移動する。 The two protruding pressing parts 21L and 21T press the upper portions 13b of the brake shoes 13L and 13T, respectively. Due to the protrusion of the two pressing portions 21L and 21T, the two brake shoes 13L and 13T respectively rotate around the rotation center C1 and move so that the upper portions 13b are separated from each other in the vehicle front-rear direction. As a result, the two brake shoes 13L and 13T move radially outward of the center of rotation C of the right rear wheel 2RR.
　各ブレーキシュー１３Ｌ、１３Ｔの外周部には、円筒面に沿う帯状のライニング１３ｃが設けられている。これにより、二つのブレーキシュー１３Ｌ、１３Ｔの、回転中心Ｃの径方向外方への移動により、ライニング１３ｃとドラム１２の内周面１２ａとが接触し、ライニング１３ｃと内周面１２ａとの摩擦により、ドラム１２ひいては、右後輪２ＲＲのホイールが制動される。なお、ブレーキシュー１３Ｌ，１３Ｔの非制動位置と制動位置との間のストロークは微少であり、例えば１ｍｍ以下である。 A strip-shaped lining 13c is provided along the cylindrical surface on the outer periphery of each brake shoe 13L, 13T. As a result, the two brake shoes 13L and 13T move radially outward of the center of rotation C, so that the lining 13c and the inner peripheral surface 12a of the drum 12 come into contact with each other, and the friction between the lining 13c and the inner peripheral surface 12a. As a result, the drum 12 and thus the right rear wheel 2RR are braked. The stroke between the non-braking position and the braking position of the brake shoes 13L, 13T is very small, for example, 1 mm or less.
　また、ブレーキ装置３ＲＲは、復帰部材１５を備える。復帰部材１５は、ホイールシリンダ３８ＲＲ内の圧力室が除圧され、押圧部２１Ｌ、２１Ｔによる二つのブレーキシュー１３Ｌ、１３Ｔの押圧が解除された場合に、二つのブレーキシュー１３Ｌ、１３Ｔを、ドラム１２の内周面１２ａと接触する位置（制動位置）からドラム１２の内周面１２ａとは接触しない位置（非制動位置）へ戻すように作用する。 Also, the brake device 3RR includes a return member 15. When the pressure chamber in the wheel cylinder 38RR is depressurized and the pressing of the two brake shoes 13L, 13T by the pressing portions 21L, 21T is released, the return member 15 connects the two brake shoes 13L, 13T to the drum 12 The inner peripheral surface 12a of the drum 12 (braking position) is returned to a position (non-braking position) where the inner peripheral surface 12a of the drum 12 does not contact.
　復帰部材１５は、例えば、コイルスプリング等の弾性部材であり、ブレーキシュー１３Ｌがブレーキシュー１３Ｔに近づく方向の力およびブレーキシュー１３Ｔがブレーキシュー１３Ｌに近付く方向の力を与える。すなわち、復帰部材１５は、二つのブレーキシュー１３Ｌ、１３Ｔがドラム１２の内周面１２ａから離れる方向の力を与えている。復帰部材１５は、付勢部材や弾性部材とも称される。 The return member 15 is, for example, an elastic member such as a coil spring, and gives a force in a direction in which the brake shoe 13L approaches the brake shoe 13T and a force in a direction in which the brake shoe 13T approaches the brake shoe 13L. That is, the return member 15 gives a force in a direction in which the two brake shoes 13L and 13T move away from the inner peripheral surface 12a of the drum 12. The return member 15 is also called an urging member or an elastic member.
　また、ブレーキ装置３ＲＲは、電動駐車ブレーキ２として、移動機構１６を備える。ＥＰＢモータ６０および運動変換機構を含む駆動機構（不図示）の作動に基いて、移動機構１６は、二つのブレーキシュー１３Ｌ、１３Ｔを非制動位置から制動位置に移動させる。 Further, the brake device 3RR includes a moving mechanism 16 as the electric parking brake 2. The movement mechanism 16 moves the two brake shoes 13L and 13T from the non-braking position to the braking position based on the operation of the driving mechanism (not shown) including the EPB motor 60 and the motion converting mechanism.
　移動機構１６は、バックプレート１４の車幅方向外方に設けられている。移動機構１６は、押圧レバー６１と、ケーブル６２と、ホイールシリンダ３８ＲＲと、を含む。 The moving mechanism 16 is provided outside the back plate 14 in the vehicle width direction. The moving mechanism 16 includes a pressing lever 61, a cable 62, and a wheel cylinder 38RR.
　押圧レバー６１は、二つのブレーキシュー１３Ｌ、１３Ｔのうち一方、例えば図２において、左側のブレーキシュー１３Ｔと、バックプレート１４との間に設けられ、当該ブレーキシュー１３Ｔに回動中心Ｃ２回りに回動可能に支持されている。ここで、回動中心Ｃ２は、ブレーキシュー１３Ｌの、回動中心Ｃ１とは反対側（図２では上側）の端部に位置され、回動中心Ｃ１と略平行である。 The pressing lever 61 is provided between one of the two brake shoes 13L and 13T, for example, the left brake shoe 13T in FIG. 2 and the back plate 14, and rotates around the rotation center C2 on the brake shoe 13T. It is movably supported. Here, the rotation center C2 is located at the end of the brake shoe 13L on the opposite side (upper side in FIG. 2) of the rotation center C1 and is substantially parallel to the rotation center C1.
　ケーブル６２は、バックプレート１４に略沿って移動し、押圧レバー６１の、回動中心Ｃ２から遠い側の下端部６１ａを、他方、例えば、図２においては、右側のブレーキシュー３Ｌに近付く方向に動かすこととなる。押圧レバー６１がケーブル６２によって動かされた作動位置ＰＬ１は、図２中に二点鎖線で示されている。 The cable 62 moves substantially along the back plate 14 so that the lower end portion 61a of the pressing lever 61 on the side far from the rotation center C2 approaches the other side, for example, in FIG. 2, the brake shoe 3L on the right side. It will be moved. The operating position PL1 in which the pressing lever 61 is moved by the cable 62 is shown by a chain double-dashed line in FIG.
　押圧レバー６１は、ブレーキシュー１３Ｔの内周面に当接する突起６１ｂを有している。この突起６１ｂにより、押圧レバー６１のケーブル６２によって動かされる前の状態での初期位置ＰＬ０が定まっている。突起６１ｂは、初期位置設定部とも称される。 The pressing lever 61 has a protrusion 61b that comes into contact with the inner peripheral surface of the brake shoe 13T. The projection 61b defines the initial position PL0 of the pressing lever 61 before it is moved by the cable 62. The protrusion 61b is also referred to as an initial position setting unit.
　そして、ホイールシリンダ３８ＲＲに移動可能に収容された可動部品である押圧部２１Ｌ、２１Ｔが、ケーブル６２によって動かされる押圧レバー６１と、当該押圧レバー６１と連結されたブレーキシュー１３Ｔとは別のブレーキシュー１３Ｌと、の間に介在して突っ張ることができる。ここで、押圧レバー６１と可動部品である押圧部２１Ｔとの接続位置Ｐ１は、回動中心Ｃ２と、ケーブル６２と押圧レバー６１との接続位置Ｐ２と、の間に設定されている。 The pressing portions 21L and 21T, which are movable parts housed movably in the wheel cylinder 38RR, are different from the pressing lever 61 that is moved by the cable 62 and the brake shoe 13T that is connected to the pressing lever 61. It can be stretched by interposing between 13L and. Here, the connection position P1 between the pressing lever 61 and the pressing portion 21T which is a movable part is set between the rotation center C2 and the connection position P2 between the cable 62 and the pressing lever 61.
　このような構成において、ＥＰＢモータ６０の作動によりケーブル６２が引かれて図２の右方へ動くことにより、押圧レバー６１が、初期位置ＰＬ０からブレーキシュー１３Ｌに近付く方向へ動くと（矢印ａ、作動位置ＰＬ１）、押圧レバー６１はホイールシリンダ３８ＲＲの可動部品である押圧部２１Ｌを介してブレーキシュー１３Ｌを押す（矢印ｂ）。 In such a configuration, when the EPB motor 60 is actuated to pull the cable 62 and move it to the right in FIG. 2, the pressing lever 61 moves from the initial position PL0 toward the brake shoe 13L (arrow a, In the operating position PL1), the pressing lever 61 presses the brake shoe 13L via the pressing portion 21L that is a movable part of the wheel cylinder 38RR (arrow b).
　これにより、ブレーキシュー１３Ｌは、非制動位置から回動中心Ｃ１回りに回動し（矢印ｃ）、ドラム１２の内周面１２ａと接触する制動位置へ動く。この状態では、ケーブル６２と押圧レバー６１との接続位置Ｐ２は力点、回動中心Ｃ２は支点、押圧レバー６１と可動部品である押圧部２１Ｌ、２１Ｔとの接続位置Ｐ１は作用点に相当する。さらに、ブレーキシュー３Ｌが、内周面１２ａに接触した状態で、押圧レバー６１が図１の右方、すなわち、可動部品１１０がブレーキシュー３Ｌを押す方向へ動くと（矢印ｂ）、可動部品１１０が突っ張ることにより、押圧レバー６１は可動部品１１０との接続位置Ｐ１を支点として、押圧レバー６１の動く方向とは逆方向、すなわち、図２における反時計回りに回動する（矢印ｄ）。 As a result, the brake shoe 13L rotates from the non-braking position around the rotation center C1 (arrow c) and moves to the braking position where it contacts the inner peripheral surface 12a of the drum 12. In this state, the connection position P2 between the cable 62 and the pressing lever 61 corresponds to the force point, the rotation center C2 corresponds to the fulcrum, and the connection position P1 between the pressing lever 61 and the pressing portions 21L and 21T that are movable parts corresponds to the action point. When the brake shoe 3L is in contact with the inner peripheral surface 12a, the pressing lever 61 moves to the right in FIG. 1, that is, when the movable part 110 moves in the direction of pushing the brake shoe 3L (arrow b), the movable part 110. When the pressing lever 61 is stretched, the pressing lever 61 rotates in a direction opposite to the moving direction of the pressing lever 61, that is, counterclockwise in FIG. 2 (arrow d) with the connection position P1 with the movable component 110 as a fulcrum.
　これにより、ブレーキシュー１３Ｔは、非制動位置から回動中心Ｃ１回りに回動し、ドラム１２の内周面１２ａと接触する制動位置へ動く。上述したように、移動機構１６の作動により、ブレーキシュー１３Ｌ、１３Ｔは、いずれも非制動位置から制動位置へ動くこととなる。なお、ブレーキシュー１３Ｌがドラム１２の内周面１２ａに接触した以降の状態では、押圧レバー６１と可動部品１１０との接続位置Ｐ１が支点となる。 As a result, the brake shoe 13T rotates from the non-braking position around the rotation center C1 and moves to the braking position where it contacts the inner peripheral surface 12a of the drum 12. As described above, the operation of the moving mechanism 16 causes the brake shoes 13L and 13T to move from the non-braking position to the braking position. In the state after the brake shoe 13L contacts the inner peripheral surface 12a of the drum 12, the connection position P1 between the pressing lever 61 and the movable component 110 serves as a fulcrum.
　また、ブレーキシュー１３Ｌが非制動位置に戻ると同時に押圧レバー６１の突起６１ｂがブレーキシュー１３Ｔの内周面に当接し、押圧レバー６１が初期位置に戻る。このように、本実施形態では、ホイールシリンダ３８ＲＲの可動部品である押圧部２１Ｌ、２１Ｔが、ブレーキ装置３ＲＲが電動駐車ブレーキ２として作動する際に、押圧レバー６１とともにブレーキシュー１３Ｌ、１３Ｔ間に介在するストラットとして機能する。 Also, at the same time when the brake shoe 13L returns to the non-braking position, the protrusion 61b of the pressing lever 61 contacts the inner peripheral surface of the brake shoe 13T, and the pressing lever 61 returns to the initial position. As described above, in the present embodiment, the pressing portions 21L and 21T that are movable parts of the wheel cylinder 38RR are interposed between the pressing lever 61 and the brake shoes 13L and 13T when the brake device 3RR operates as the electric parking brake 2. Functions as a strut.
　次に、図３を参照して、制動制御装置２００の機能的構成について説明する。図３は、第１実施形態における制動制御装置２００の機能的構成を示すブロック図である。制動制御装置２００は、例えば、プロセッサやメモリなどの通常のコンピュータと同様のハードウェアを備えたブレーキＥＣＵ（Electronic　Control　Unit）の一部を構成する。なお、制動制御装置２００は、ブレーキＥＣＵの他の部分と一体化されてもよいし、当該他の部分とは別個に構成されてもよい。 Next, the functional configuration of the braking control device 200 will be described with reference to FIG. FIG. 3 is a block diagram showing a functional configuration of the braking control device 200 according to the first embodiment. The braking control device 200 constitutes, for example, a part of a brake ECU (Electronic Control Unit) including hardware similar to an ordinary computer such as a processor and a memory. The braking control device 200 may be integrated with other parts of the brake ECU, or may be configured separately from the other parts.
　制動制御装置２００は、液圧ブレーキ１と電動駐車ブレーキ２とを制御可能に構成されている。制動制御装置２００は、機能的構成として、検出部２０１と、制御部２０２と、を備える。制御部２０２は、液圧ブレーキ制御部２０３と、ＥＰＢ制御部２０４（制御部）と、を備える。これらの機能的構成は、例えば、制動制御装置２００のプロセッサがメモリに格納された種々のプログラムを実行した結果として実現される。なお、これらの機能的構成の一部または全部が専用の回路などによって実現されてもよい。 The braking control device 200 is configured to control the hydraulic brake 1 and the electric parking brake 2. The braking control device 200 includes a detection unit 201 and a control unit 202 as a functional configuration. The control unit 202 includes a hydraulic brake control unit 203 and an EPB control unit 204 (control unit). These functional configurations are realized, for example, as a result of the processor of the braking control device 200 executing various programs stored in the memory. Note that part or all of these functional configurations may be realized by a dedicated circuit or the like.
　また、制動制御装置２００は、路面の勾配（車両の前後方向の傾き）を検出する加速度センサ、ジャイロセンサ等として構成された勾配検知センサ３の出力に基いて動作する機能を有する。 The braking control device 200 also has a function of operating based on the output of the gradient detection sensor 3 configured as an acceleration sensor, a gyro sensor, or the like that detects the gradient of the road surface (the inclination of the vehicle in the front-rear direction).
　検出部２０１は、液圧ブレーキ１に液圧制動力を発生させるための操作（液圧ブレーキ操作）や、駐車制動力を発生可能な状態に設定するための操作（駐車ブレーキ操作）などの運転者による制動操作を検出する。ここで、液圧ブレーキ操作とは、例えば、運転者によるブレーキペダル３１の操作である。一方、駐車ブレーキ操作とは、例えば、運転席付近に設けられるＥＰＢスイッチやレバー（図１には不図示）などの操作である。すなわち、検出部２０１は、ストロークセンサ５１などの検出結果に基いて液圧ブレーキ操作を検出し、ＥＰＢスイッチやレバーなどの操作に応じて出力される電気信号などに基いて駐車ブレーキ操作を検出する。 The detection unit 201 is a driver who performs an operation (a hydraulic brake operation) for generating a hydraulic braking force on the hydraulic brake 1 or an operation (a parking brake operation) for setting a state in which the parking braking force can be generated. The braking operation by is detected. Here, the hydraulic brake operation is, for example, an operation of the brake pedal 31 by the driver. On the other hand, the parking brake operation is, for example, an operation of an EPB switch or a lever (not shown in FIG. 1) provided near the driver's seat. That is, the detection unit 201 detects the hydraulic brake operation based on the detection result of the stroke sensor 51 and the like, and detects the parking brake operation based on the electric signal output according to the operation of the EPB switch and the lever. ..
　液圧ブレーキ制御部２０３は、液圧ブレーキ１に発生させる液圧制動力を制御可能に構成されている。また、ＥＰＢ制御部２０４は、電動駐車ブレーキ２に発生させる駐車制動力を制御可能に構成されている。 The hydraulic brake control unit 203 is configured to control the hydraulic braking force generated in the hydraulic brake 1. Further, the EPB control unit 204 is configured to be able to control the parking braking force generated in the electric parking brake 2.
　ＥＰＢ制御部２０４は、具体的には、ＥＰＢモータ６０を正回転させることによってブレーキシュー１３Ｌ、１３Ｔをドラム１２の内周面１２ａに当接させて制動力を増加させるロック制御、および、ＥＰＢモータ６０を逆回転させることによって制動力を減少させるリリース制御を実行することで、電動駐車ブレーキ２による制動を制御する。 Specifically, the EPB control unit 204 locks the brake shoes 13L and 13T to the inner peripheral surface 12a of the drum 12 by positively rotating the EPB motor 60 to increase the braking force, and the EPB motor. The braking by the electric parking brake 2 is controlled by executing the release control that reduces the braking force by rotating the 60 in the reverse direction.
　ところで、例えば、短時間に多くのブレーキ動作が実行されると、ドラム１２が熱膨張によって一時的に大径となる場合がある。そして、その状態でロック制御を実行して所定の制動力を発生させると、その後にドラム１２が冷却して径方向に収縮したときに、過大な制動力（クランプ力）が発生してしまうことがある。 However, for example, if many braking operations are performed in a short time, the drum 12 may temporarily have a large diameter due to thermal expansion. Then, if the lock control is executed in that state to generate a predetermined braking force, an excessive braking force (clamping force) will be generated when the drum 12 subsequently cools and contracts in the radial direction. There is.
　そこで、以下では、ドラム１２が熱膨張によって一時的に大径となった電動駐車ブレーキ２に対して制動制御を行う場合に、その後にドラム１２が冷却して径方向に収縮しても過大な制動力が発生しないようにすることができる制動制御装置２００について説明する。 Therefore, in the following description, when the braking control is performed on the electric parking brake 2 whose diameter has temporarily increased due to thermal expansion, even if the drum 12 cools and contracts in the radial direction after that, it is excessive. A braking control device 200 capable of preventing a braking force from being generated will be described.
　ＥＰＢ制御部２０４は、電動駐車ブレーキ２による制動を制御する場合に、ドラム１２の温度を取得または推定し、当該温度に基いて、その後にドラム１２が冷却して径方向に収縮したときに制動力が所定の上限制動力を超えないように、ロック制御、および、リリース制御の少なくともいずれかにより制動力を調整する制動力調整制御を実行する。 The EPB control unit 204 acquires or estimates the temperature of the drum 12 when controlling the braking by the electric parking brake 2, and based on the temperature, controls the EPB control unit when the drum 12 cools and contracts in the radial direction. The braking force adjustment control for adjusting the braking force by at least one of the lock control and the release control is executed so that the power does not exceed the predetermined upper limit braking force.
　ドラム１２の温度を計測する温度センサ（不図示）が設けられている場合、ＥＰＢ制御部２０４は、その温度センサからドラム１２の温度の情報を取得することができる。 When a temperature sensor (not shown) that measures the temperature of the drum 12 is provided, the EPB control unit 204 can acquire the temperature information of the drum 12 from the temperature sensor.
　また、ドラム１２の温度を計測する温度センサ（不図示）が設けられていない場合、ＥＰＢ制御部２０４は、例えば、車速やブレーキ動作の履歴情報に基いて、ドラム１２の温度を推定することができる。例えば、ブレーキ動作の強さの度合いや頻度によってドラム１２の温度上昇の度合いが変わると考えられ、ＥＰＢ制御部２０４は、そのことを示す関数やマップの情報等を予め記憶しておくことによってドラム１２の温度を推定することができる。 If a temperature sensor (not shown) that measures the temperature of the drum 12 is not provided, the EPB control unit 204 may estimate the temperature of the drum 12 based on, for example, vehicle speed and history information of brake operation. it can. For example, it is considered that the degree of temperature rise of the drum 12 changes depending on the degree and frequency of the braking operation, and the EPB control unit 204 stores the function and map information indicating this in advance by the drum. Twelve temperatures can be estimated.
　なお、ブレーキ動作は、例えば、運転者によるブレーキペダル３１の操作に基く液圧ブレーキ動作や、運転者によるＥＰＢスイッチやレバーなどの操作に基く電動駐車ブレーキ動作だけでなく、ＡＢＳ（Antilock　Brake　System）やＥＳＣ（Electronic　Stability　Control：横滑り防止装置）に基く液圧ブレーキ動作等も含む。また、ドラム１２の温度を推定するのに、外気温センサ（不図示）からの得られる外気温の情報等の他の情報をさらに用いてもよい。 The braking operation is not limited to, for example, a hydraulic braking operation based on the driver's operation of the brake pedal 31 and an electric parking brake operation based on the operation of the EPB switch or lever by the driver, but also ABS (Antilock Brake System). Also includes hydraulic brake operation based on ESC (Electronic Stability Control). Further, in order to estimate the temperature of the drum 12, other information such as information on the outside air temperature obtained from an outside air temperature sensor (not shown) may be further used.
　また、ＥＰＢ制御部２０４は、ドラム１２の温度の時間変化の情報であるドラム温度変化情報を記憶している。つまり、ＥＰＢ制御部２０４は、ドラム１２の温度が高くなっている場合に、そのドラム温度変化情報を参照することで、その後の経過時間ごとのドラム１２の温度を推定することができる。また、ＥＰＢ制御部２０４は、ドラム１２の温度と熱膨張率の関係を示す情報であるドラム熱膨張率情報を記憶している。 The EPB control unit 204 also stores drum temperature change information, which is information about the time change of the temperature of the drum 12. That is, when the temperature of the drum 12 is high, the EPB control unit 204 can estimate the temperature of the drum 12 for each subsequent elapsed time by referring to the drum temperature change information. The EPB control unit 204 also stores drum thermal expansion coefficient information, which is information indicating the relationship between the temperature of the drum 12 and the thermal expansion coefficient.
　次に、図４を参照して、第１実施形態における各構成等の経時的変化の様子について説明する。図４は、第１実施形態における各構成等の経時的変化の様子を示すタイムチャートである。ここでは、ＥＰＢ制御部２０４は、制動力調整制御を実行する場合に、ドラム１２の温度に基いて、その後にドラム１２が冷却して径方向に収縮したときに制動力が所定の上限制動力（例えば、リリース動作可能な最大クランプ力）を超えないように、ロック制御とリリース制御を繰り返し実行する。 Next, with reference to FIG. 4, the state of changes over time of the components and the like in the first embodiment will be described. FIG. 4 is a time chart showing changes over time of the components and the like in the first embodiment. Here, when executing the braking force adjustment control, the EPB control unit 204 determines, based on the temperature of the drum 12, that the braking force is a predetermined upper limit braking force when the drum 12 subsequently cools and contracts in the radial direction. (For example, the lock control and the release control are repeatedly executed so as not to exceed the maximum clamp force at which the release operation is possible.)
　図４では、上から順に、ドラム１２の温度、ＥＰＢ状態（電動駐車ブレーキ２の状態。ロック、保持、リリース）、クランプ力（制動力）の経時的変化の概要を示している。ドラム１２の温度は、時刻ｔ０で有意に高く、以降、次第に低下する。 In FIG. 4, the temperature of the drum 12, EPB state (state of the electric parking brake 2, lock, hold, release), and clamping force (braking force) are shown in chronological order from top to bottom. The temperature of the drum 12 is significantly high at time t0, and then gradually decreases.
　その場合、ＥＰＢ制御部２０４は、まず、時刻ｔ０～ｔ１の間、ロック制御を行い、クランプ力を適正クランプ力まで上昇させる。次に、時刻ｔ１～ｔ２の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ２～ｔ３の間、リリース制御を行い、クランプ力を０まで低下させる。 In that case, the EPB control unit 204 first performs lock control from time t0 to t1 to increase the clamping force to an appropriate clamping force. Next, from time t1 to t2, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t2 to time t3 to reduce the clamping force to zero.
　次に、ＥＰＢ制御部２０４は、時刻ｔ３～ｔ４の間、ロック制御を行い、クランプ力を適正クランプ力まで上昇させる。次に、時刻ｔ４～ｔ５の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ５～ｔ６の間、リリース制御を行い、クランプ力を０まで低下させる。 Next, the EPB control unit 204 performs lock control from time t3 to t4 to increase the clamping force to the proper clamping force. Next, from time t4 to t5, the EPB control unit 204 keeps the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t5 to time t6 to reduce the clamping force to zero.
　次に、ＥＰＢ制御部２０４は、時刻ｔ６～ｔ７の間、ロック制御を行い、クランプ力を適正クランプ力まで上昇させる。次に、時刻ｔ７～ｔ８の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ８～ｔ９の間、リリース制御を行い、クランプ力を０まで低下させる。 Next, the EPB control unit 204 performs lock control from time t6 to time t7 to raise the clamping force to the proper clamping force. Next, from time t7 to t8, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t8 to time t9 to reduce the clamping force to zero.
　次に、ＥＰＢ制御部２０４は、時刻ｔ９～ｔ１０の間、ロック制御を行い、クランプ力を適正クランプ力まで上昇させる。時刻ｔ１０以降、ドラム１２の温度低下量が小さく、ドラム１２の径収縮はほとんど起きず、適正クランプ力が維持される。 Next, the EPB control unit 204 performs lock control from time t9 to t10 to increase the clamping force to the proper clamping force. After time t10, the amount of decrease in temperature of the drum 12 is small, the diameter of the drum 12 is hardly contracted, and the proper clamping force is maintained.
　このようにして、ＥＰＢ制御部２０４がロック制御とリリース制御を繰り返し実行することで、ドラム１２の温度低下にともなう径収縮による過大な制動力（クランプ力）の発生を回避できる。一方、図４において破線Ｂに示すように、最初に（時刻ｔ０～ｔ１の間）ロック制御を行って、その後放置すると、クランプ力がリリース動作可能な最大クランプ力を超えてしまう。したがって、過大なクランプ力によって、ＥＰＢモータ６０の起動トルクが不足し、リリース制御を実行できない事態等が発生してしまう。 By thus repeatedly performing the lock control and the release control by the EPB control unit 204, it is possible to avoid the generation of an excessive braking force (clamping force) due to the diameter contraction accompanying the temperature decrease of the drum 12. On the other hand, as shown by the broken line B in FIG. 4, if the lock control is first performed (between times t0 and t1) and then left as it is, the clamping force exceeds the maximum clamping force capable of releasing operation. Therefore, due to the excessive clamping force, the starting torque of the EPB motor 60 becomes insufficient, and the situation in which the release control cannot be executed occurs.
　次に、図５を参照して、制動制御装置２００が実行する一連の処理について説明する。図５は、第１実施形態における制動制御装置２００が実行する一連の処理を示すフローチャートである。 Next, a series of processing executed by the braking control device 200 will be described with reference to FIG. FIG. 5 is a flowchart showing a series of processes executed by the braking control device 200 in the first embodiment.
　まず、ステップＳ１において、ＥＰＢ制御部２０４は、電動駐車ブレーキ２に対する制動制御を開始するか否かを判定し、Ｙｅｓの場合はステップＳ２に進み、Ｎｏの場合はステップＳ１に戻る。このステップＳ１では、例えば、運転席付近に設けられるＥＰＢスイッチやレバーなどによる駐車ブレーキ操作があった場合、ＥＰＢ制御部２０４はＹｅｓと判定する。 First, in step S1, the EPB control unit 204 determines whether or not to start the braking control for the electric parking brake 2. If Yes, the process proceeds to step S2, and if No, the process returns to step S1. In this step S1, for example, when there is a parking brake operation by an EPB switch or lever provided near the driver's seat, the EPB control unit 204 determines Yes.
　ステップＳ２において、ＥＰＢ制御部２０４は、ロック制御を実行する。次に、ステップＳ３において、ＥＰＢ制御部２０４は、ドラム１２の温度を特定（取得または推定）する。 In step S2, the EPB control unit 204 executes lock control. Next, in step S3, the EPB control unit 204 specifies (acquires or estimates) the temperature of the drum 12.
　次に、ステップＳ４において、ＥＰＢ制御部２０４は、ステップＳ３で特定したドラム１２の温度、ドラム温度変化情報、ドラム熱膨張率情報等に基いて、リリース制御が必要か否かを判定し、Ｙｅｓの場合はステップＳ５に進み、Ｎｏの場合は処理を終了する。このステップＳ４では、ＥＰＢ制御部２０４は、例えば、リリース制御を行わないと、クランプ力がリリース動作可能な最大クランプ力を超えてしまう場合、リリース制御が必要であると判定する。 Next, in step S4, the EPB control unit 204 determines whether or not release control is necessary based on the temperature of the drum 12, the drum temperature change information, the drum thermal expansion coefficient information, and the like identified in step S3, and Yes. If No, the process proceeds to step S5, and if No, the process ends. In step S4, the EPB control unit 204 determines that release control is necessary if the clamp force exceeds the maximum clamp force at which the release operation can be performed unless release control is performed.
　ステップＳ５において、ＥＰＢ制御部２０４は、リリース制御を実行し、ステップＳ２に戻る。 In step S5, the EPB control unit 204 executes release control, and returns to step S2.
　このようにして、第１実施形態の制動制御装置２００によれば、ドラム１２が熱膨張によって一時的に大径となっていてその後に冷却して径収縮する場合でも、過大な制動力が発生しないようにすることができる。具体的には、ＥＰＢ制御部２０４がロック制御とリリース制御を繰り返し実行することで、ドラム１２の温度低下にともなう径収縮による過大な制動力（クランプ力）の発生を回避することができる。したがって、過大なクランプ力によってＥＰＢモータ６０の起動トルクが不足してリリース制御を実行できない事態等を確実に回避できる。 In this way, according to the braking control device 200 of the first embodiment, an excessive braking force is generated even when the drum 12 temporarily has a large diameter due to thermal expansion and then cools and contracts in diameter. You can choose not to. Specifically, the EPB control unit 204 repeatedly executes the lock control and the release control, so that it is possible to avoid the generation of an excessive braking force (clamping force) due to the diameter contraction accompanying the temperature decrease of the drum 12. Therefore, it is possible to reliably avoid a situation in which the release control cannot be executed due to insufficient starting torque of the EPB motor 60 due to an excessive clamping force.
　また、過大なクランプ力を長時間保持することによるクランプ力保持機構への過大な負荷の発生を回避することができる。 Also, it is possible to avoid the occurrence of an excessive load on the clamping force holding mechanism due to holding an excessive clamping force for a long time.
　なお、このロック制御とリリース制御の繰り返しは、二輪同時に行ってもよいし、あるいは、一輪ずつタイミングをずらして行ってもよい。例えば、車両が平坦な路面上や傾斜の緩い路面上にいて、勾配検知センサ３による出力等に基いて、二輪のすべての制動力が無くても車両が動かないと判定した場合は、二輪同時に行えばよい。 Note that the lock control and the release control may be repeated for two wheels at the same time, or the timing may be shifted for each wheel. For example, if the vehicle is on a flat road surface or a road surface having a gentle slope and it is determined that the vehicle does not move even if all the braking forces of the two wheels are absent based on the output from the gradient detection sensor 3, etc. Just go.
　また、車両が傾斜の急な路面上にいて、勾配検知センサ３による出力等に基いて、二輪のすべての制動力が無いと車両が動いてしまうと判定した場合は、一輪ずつタイミングをずらして（二輪のすべての制動力が無い状態を回避しながら）ロック制御とリリース制御の繰り返しを行ってもよいし、あるいは、液圧制動力やＰレンジ等によって停車状態を保持しながら二輪同時に行ってもよい。 Further, if the vehicle is on a road surface having a steep slope and it is determined that the vehicle will move unless all braking forces of the two wheels are present, based on the output from the gradient detection sensor 3, etc., the timing is shifted one wheel at a time. The lock control and the release control may be repeated (while avoiding a state where all the two wheels have no braking force), or the two wheels may be simultaneously performed while the vehicle is stopped by the hydraulic braking force or the P range. Good.
　つまり、例えば、ＥＰＢ制御部２０４は、ＥＰＢ制御部２０４が車両の停車状態を保持するために必要な目標制動力を発生させなくても、電動駐車ブレーキ２とは異なる保持手段（例えば、液圧ブレーキ１、駆動装置（トランスミッション等）、駆動トルク、回生制動力等。以下同様）により車両の停車状態を保持可能な状態にあると判断した場合に、制動力調整制御を実行するようにしてもよい。 That is, for example, the EPB control unit 204 does not generate the target braking force necessary for the EPB control unit 204 to maintain the stopped state of the vehicle, but the holding means (for example, the hydraulic pressure) different from the electric parking brake 2. Even if the braking force adjustment control is executed when it is determined that the vehicle stop state can be maintained by the brake 1, the drive device (transmission, etc.), the drive torque, the regenerative braking force, etc. Good.
　また、ＥＰＢ制御部２０４は、ＥＰＢ制御部２０４が車両の停車状態を保持するために必要な目標制動力を発生させなくても、電動駐車ブレーキ２とは異なる保持手段により車両を停車状態に保持可能にした後に、制動力調整制御を実行するようにしてもよい。 Further, the EPB control unit 204 holds the vehicle in a stopped state by a holding means different from the electric parking brake 2 even if the EPB control unit 204 does not generate the target braking force required to hold the stopped state of the vehicle. The braking force adjustment control may be executed after the enabling.
　また、ＥＰＢ制御部２０４は、電動駐車ブレーキ２が設けられている複数の車輪のうちのいずれか一輪のみに発生している制動力で車両の停車状態を保持できると判断した後、または、その一輪のみで車両の停車状態を保持できるように制動力を増加させた後、その一輪以外の車輪に対して制動力調整制御を実行するようにしてもよい。 Further, the EPB control unit 204 determines that it is possible to maintain the stopped state of the vehicle by the braking force generated on only one of the plurality of wheels provided with the electric parking brake 2, or The braking force adjustment control may be executed for the wheels other than the one wheel after the braking force is increased so that the stopped state of the vehicle can be maintained with only one wheel.
　また、ＥＰＢ制御部２０４は、制動力調整制御を実行する前に、リリース制御を実施し、ＥＰＢモータ６０の電流値からブレーキドラムが冷却して径方向に収縮したときの熱収縮量を推定し、制動力調整制御による制動力の調整量、および、制動力調整制御を実行するタイミングの少なくともいずれかを決定するようにしてもよい。 Further, the EPB control unit 204 performs release control before executing the braking force adjustment control, and estimates the heat shrinkage amount when the brake drum cools and contracts in the radial direction from the current value of the EPB motor 60. At least one of the braking force adjustment amount by the braking force adjustment control and the timing of executing the braking force adjustment control may be determined.
（第２実施形態）
　次に、第２実施形態について説明する。第１実施形態と同様の事項については重複する説明を適宜省略する。第２実施形態は、第１実施形態と比較して、ロック制御とリリース制御を繰り返す点では同じであるが、リリース制御のときにクランプ力を０にまで低下させない点で異なっている。 (Second embodiment)
Next, a second embodiment will be described. For items similar to those in the first embodiment, redundant description will be appropriately omitted. The second embodiment is the same as the first embodiment in that lock control and release control are repeated, but is different in that the clamping force is not reduced to 0 during release control.
　図６は、第２実施形態における各構成等の経時的変化の様子を示すタイムチャートである。図６における各項目は図４と同様である。また、図４の場合と同様、ドラム１２の温度は、時刻ｔ２０で有意に高く、以降、次第に低下する。 FIG. 6 is a time chart showing changes over time of the components and the like in the second embodiment. Each item in FIG. 6 is the same as that in FIG. Further, as in the case of FIG. 4, the temperature of the drum 12 is significantly high at the time t20 and thereafter gradually decreases.
　ＥＰＢ制御部２０４は、まず、時刻ｔ２０～ｔ２１の間、ロック制御を行い、クランプ力を適正クランプ力まで上昇させる。次に、時刻ｔ２１～ｔ２２の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ２２～ｔ２３の間、リリース制御を行い、クランプ力を低下させる。 The EPB control unit 204 first performs lock control from time t20 to t21 to increase the clamping force to the proper clamping force. Next, from time t21 to t22, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t22 to time t23 to reduce the clamping force.
　次に、時刻ｔ２３～ｔ２４の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ２４～ｔ２５の間、リリース制御を行い、クランプ力を低下させる。 Next, from time t23 to t24, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t24 to time t25 to reduce the clamping force.
　次に、時刻ｔ２５～ｔ２６の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ２６～ｔ２７の間、リリース制御を行い、クランプ力を低下させる。 Next, from time t25 to t26, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t26 to time t27 to reduce the clamping force.
　次に、時刻ｔ２７～ｔ２８の間、ＥＰＢ制御部２０４はＥＰＢ状態を保持とするが、ドラム１２の温度低下にともなう径収縮によって、クランプ力は上昇する。次に、ＥＰＢ制御部２０４は、時刻ｔ２８～ｔ２９の間、リリース制御を行い、クランプ力を適正クランプ力まで低下させる。 Next, from time t27 to t28, the EPB control unit 204 maintains the EPB state, but the clamping force increases due to the diameter contraction accompanying the temperature decrease of the drum 12. Next, the EPB control unit 204 performs release control from time t28 to time t29 to reduce the clamping force to the proper clamping force.
　時刻ｔ２９以降、ドラム１２の温度低下量が小さく、ドラム１２の径収縮はほとんど起きず、適正クランプ力が維持される。 After time t29, the amount of temperature decrease of the drum 12 is small, the diameter of the drum 12 is hardly contracted, and the proper clamping force is maintained.
　このようにして、第２実施形態の制動制御装置２００によれば、ＥＰＢ制御部２０４がロック制御とリリース制御を繰り返し実行し、また、第１実施形態と異なってリリース制御でクランプ力を０にまで低下させなくても、ドラム１２の温度低下にともなう径収縮による過大な制動力（クランプ力）の発生を回避できる。 As described above, according to the braking control device 200 of the second embodiment, the EPB control unit 204 repeatedly executes the lock control and the release control, and unlike the first embodiment, the clamping force is set to 0 by the release control. It is possible to avoid the generation of an excessive braking force (clamping force) due to the diameter contraction due to the temperature decrease of the drum 12 without decreasing the temperature.
　つまり、この第２実施形態では、リリース制御で、クランプ力を０にまで低下させなくても、クランプ力がリリース動作可能な最大クランプ力を超えることがないようにすればよい。これにより、確実に車両の停車状態を保持しつつ、制動力調整制御を実施することができる。 That is, in the second embodiment, the release control does not need to reduce the clamp force to 0 so that the clamp force does not exceed the maximum clamp force at which the release operation is possible. As a result, the braking force adjustment control can be executed while the vehicle stop state is reliably maintained.
（第３実施形態）
　次に、第３実施形態について説明する。第１実施形態と同様の事項については重複する説明を適宜省略する。第３実施形態では、ＥＰＢ制御部２０４は、制動力調整制御を実行する場合に、ドラム１２の温度に基いて、その後にドラム１２が冷却して径方向に収縮したときの制動力が車両の停車状態を保持するために必要な目標制動力となるように、ロック制御を実行する。これについて、図７を参照して説明する。 (Third Embodiment)
Next, a third embodiment will be described. For items similar to those in the first embodiment, redundant description will be appropriately omitted. In the third embodiment, when executing the braking force adjustment control, the EPB control unit 204 determines the braking force when the drum 12 cools and contracts in the radial direction based on the temperature of the drum 12 thereafter. The lock control is executed so that the target braking force required to maintain the stopped state is obtained. This will be described with reference to FIG.
　図７は、第３実施形態におけるドラム温度とクランプ力の関係を示すグラフである。図７のグラフにおいて、縦軸はクランプ力（制動力）であり、横軸はドラム温度である。図７に示すように、ドラム温度がＤＴ１未満の場合はドラム１２の熱膨張が起きないので（あるいは起きても微小なので）、ロック制御で与える制動力は通常の目標制動力とすればよい。しかし、ドラム温度がＤＴ１以上の場合はドラム１２の熱膨張が有意に起きるので、ロック制御で与える制動力は、ドラム温度が高いほど、通常の目標制動力よりも小さいものとする。例えば、ドラム温度がＤＴ２のとき、ロック制御時の制動力をＰ１とすることで、その後にドラム１２が冷却して径方向に収縮したときの制動力が目標制動力（Ｐ２）となる。 FIG. 7 is a graph showing the relationship between the drum temperature and the clamping force in the third embodiment. In the graph of FIG. 7, the vertical axis represents the clamping force (braking force) and the horizontal axis represents the drum temperature. As shown in FIG. 7, when the drum temperature is lower than DT1, thermal expansion of the drum 12 does not occur (or is small even if it occurs), so the braking force applied by the lock control may be a normal target braking force. However, when the drum temperature is DT1 or higher, the thermal expansion of the drum 12 occurs significantly, so the braking force applied by the lock control is set to be smaller than the normal target braking force as the drum temperature increases. For example, when the drum temperature is DT2, the braking force at the time of lock control is set to P1, and the braking force when the drum 12 subsequently cools and contracts in the radial direction becomes the target braking force (P2).
　このようにして、第３実施形態の制動制御装置２００によれば、ＥＰＢ制御部２０４がロック制御時に与える制動力をドラム温度が高いほど小さいものとすることで、ドラム１２の温度低下にともなう径収縮による過大な制動力（クランプ力）の発生を回避できる。この方法は、例えば、車両が平坦な路面上や傾斜の緩い路面上にいて、勾配検知センサ３による出力等に基いて、二輪のすべての制動力が無くても車両が動かないと判定した場合に、特に有効である。 As described above, according to the braking control device 200 of the third embodiment, the braking force applied by the EPB control unit 204 at the time of lock control is set to be smaller as the drum temperature is higher. Generation of excessive braking force (clamping force) due to contraction can be avoided. In this method, for example, when the vehicle is on a flat road surface or a road surface having a gentle slope, and it is determined that the vehicle does not move based on the output from the slope detection sensor 3 even if all the braking forces of the two wheels are not present. It is especially effective for
（第４実施形態）
　次に、第４実施形態について説明する。第１実施形態と同様の事項については重複する説明を適宜省略する。第４実施形態では、ＥＰＢ制御部２０４は、ロック制御時のＥＰＢ電流値（ＥＰＢモータ６０の駆動電流値）とリリース制御時のＥＰＢ電流値を比較することで、ドラム１２の熱膨張の度合いを推定する。これについて、図８を参照して説明する。 (Fourth Embodiment)
Next, a fourth embodiment will be described. For items similar to those in the first embodiment, redundant description will be appropriately omitted. In the fourth embodiment, the EPB control unit 204 compares the EPB current value during lock control (drive current value of the EPB motor 60) with the EPB current value during release control to determine the degree of thermal expansion of the drum 12. presume. This will be described with reference to FIG.
　図８は、第４実施形態におけるロック制御時とリリース制御時のＥＰＢ電流値の経時的変化の様子を示すグラフである。ＥＰＢ制御部２０４は、図８に示す、ロック制御における最後のＥＰＢ電流値Ｉ１（時刻ｔ３１）と、リリース制御における最初の突入電流直後に減少度合が緩くなるときのＥＰＢ電流値Ｉ２（時刻ｔ３２）を比較することで、ドラム１２の熱膨張の度合いを推定することができる。そのために、ＥＰＢ制御部２０４は、例えば、ＥＰＢ電流値Ｉ１とＥＰＢ電流値Ｉ２の比較結果とそれに対応するドラム１２の熱膨張の度合いに関する情報を予め記憶しておけばよい。 FIG. 8 is a graph showing how the EPB current value changes with time during lock control and release control in the fourth embodiment. The EPB control unit 204 shown in FIG. 8 shows the last EPB current value I1 (time t31) in the lock control and the EPB current value I2 (time t32) when the decrease degree becomes gentle immediately after the first inrush current in the release control. The degree of thermal expansion of the drum 12 can be estimated by comparing Therefore, the EPB control unit 204 may previously store, for example, the comparison result of the EPB current value I1 and the EPB current value I2 and the information about the degree of thermal expansion of the drum 12 corresponding thereto.
　したがって、ＥＰＢ制御部２０４は、まず、ロック制御を行った後、クランプ力がリリース動作可能な最大クランプ力を超える可能性が発生するときより前にリリース制御を実行する。そして、その後、ＥＰＢ制御部２０４は、ＥＰＢ電流値Ｉ１とＥＰＢ電流値Ｉ２を比較してドラム１２の熱膨張の度合いを推定する。そうすることで、ＥＰＢ制御部２０４は、そのドラム１２の熱膨張の度合いに応じてクランプ力を弱めるためのリリース制御を適宜実行することができる。この方法によれば、ドラム１２の熱膨張の度合いを推定するために、車速やブレーキ動作の履歴情報が不要となる。 Therefore, the EPB control unit 204 first performs the lock control and then executes the release control before the possibility that the clamp force exceeds the maximum clamp force at which the release operation can be performed. Then, after that, the EPB control unit 204 estimates the degree of thermal expansion of the drum 12 by comparing the EPB current value I1 and the EPB current value I2. By doing so, the EPB control unit 204 can appropriately execute release control for weakening the clamping force according to the degree of thermal expansion of the drum 12. According to this method, in order to estimate the degree of thermal expansion of the drum 12, the vehicle speed and the history information of the brake operation are unnecessary.
　以上、本発明の実施形態を説明したが、上述した実施形態はあくまで一例であって、発明の範囲を限定することは意図していない。上述した新規な実施形態は、様々な形態で実施されることが可能であり、発明の要旨を逸脱しない範囲で、種々の省略、置き換え、または変更を行うことができる。また、上述した実施形態およびその変形は、発明の範囲や要旨に含まれるとともに、請求の範囲に記載された発明とその均等の範囲に含まれる。 The embodiments of the present invention have been described above, but the above-described embodiments are merely examples, and are not intended to limit the scope of the invention. The novel embodiment described above can be implemented in various forms, and various omissions, replacements, or changes can be made without departing from the spirit of the invention. Further, the above-described embodiments and modifications thereof are included in the scope and the gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Claims (7)

  1. 　車両の複数の車輪に対して設けられた電動ドラムブレーキ装置を制御する制動制御装置であって、
    　前記電動ドラムブレーキ装置におけるモータを回転させることによって制動部材を被制動部材の内周面に当接させて制動力を増加させるロック制御、および、前記モータを回転させることによって前記制動力を減少させるリリース制御を実行することで、前記電動ドラムブレーキ装置による制動を制御する制御部を備え、
    　前記制御部は、前記電動ドラムブレーキ装置による制動を制御する場合に、ブレーキドラムの温度を取得または推定し、前記温度に基いて、その後に前記ブレーキドラムが冷却して径方向に収縮したときに制動力が所定の上限制動力を超えないように、前記ロック制御、および、前記リリース制御の少なくともいずれかにより前記制動力を調整する制動力調整制御を実行する、制動制御装置。     A braking control device for controlling an electric drum brake device provided for a plurality of wheels of a vehicle,
    Lock control for increasing the braking force by bringing the braking member into contact with the inner peripheral surface of the member to be braked by rotating the motor in the electric drum brake device, and reducing the braking force by rotating the motor By performing a release control, a control unit for controlling braking by the electric drum brake device is provided,
    When controlling the braking by the electric drum brake device, the control unit acquires or estimates the temperature of the brake drum, and based on the temperature, when the brake drum subsequently cools and contracts in the radial direction. A braking control device that executes a braking force adjustment control that adjusts the braking force by at least one of the lock control and the release control so that the braking force does not exceed a predetermined upper limit braking force.
  2. 　前記制御部は、前記制動力調整制御を繰り返し実行する、請求項１に記載の制動制御装置。 The braking control device according to claim 1, wherein the control unit repeatedly executes the braking force adjustment control.
  3. 　前記制御部は、前記制動力調整制御を実行する場合に、前記温度に基いて、その後に前記ブレーキドラムが冷却して径方向に収縮したときの制動力が前記車両の停車状態を保持するために必要な目標制動力となるように、前記ロック制御を実行する、請求項１または請求項２に記載の制動制御装置。 When the control unit executes the braking force adjustment control, based on the temperature, the braking force when the brake drum cools and contracts in the radial direction thereafter holds the stopped state of the vehicle. The braking control device according to claim 1 or 2, wherein the lock control is executed so that a target braking force required for the above is obtained.
  4. 　前記制御部は、前記制御部が前記車両の停車状態を保持するために必要な目標制動力を発生させなくても、前記電動ドラムブレーキ装置とは異なる保持手段により前記車両の停車状態を保持可能な状態にあると判断した場合に、前記制動力調整制御を実行する、請求項１から請求項３のいずれか一項に記載の制動制御装置。 Even if the control unit does not generate the target braking force required to maintain the stopped state of the vehicle, the control unit can hold the stopped state of the vehicle by a holding unit different from the electric drum brake device. The braking control device according to any one of claims 1 to 3, which executes the braking force adjustment control when it is determined that the braking control device is in such a state.
  5. 　前記制御部は、前記制御部が前記車両の停車状態を保持するために必要な目標制動力を発生させなくても、前記電動ドラムブレーキ装置とは異なる保持手段により前記車両を停車状態に保持可能にした後に、前記制動力調整制御を実行する、請求項１から請求項３のいずれか一項に記載の制動制御装置。 The control unit can hold the vehicle in the stopped state by a holding unit different from the electric drum brake device, even if the control unit does not generate the target braking force required to maintain the stopped state of the vehicle. The braking control device according to claim 1, wherein the braking force adjustment control is executed after the setting.
  6. 　前記制御部は、前記電動ドラムブレーキ装置が設けられている前記複数の車輪のうちのいずれか一輪のみに発生している前記制動力で前記車両の停車状態を保持できると判断した後、または、前記一輪のみで前記車両の停車状態を保持できるように前記制動力を増加させた後、前記一輪以外の前記車輪に対して前記制動力調整制御を実行する、請求項１または請求項２に記載の制動制御装置。 After the controller determines that it is possible to maintain the stopped state of the vehicle by the braking force generated only on one of the plurality of wheels provided with the electric drum brake device, or The braking force adjustment control is executed for the wheels other than the one wheel after increasing the braking force so that the vehicle can be held in a stopped state by only the one wheel. Braking control device.
  7. 　前記制御部は、前記制動力調整制御を実行する前に、前記リリース制御を実施し、前記モータの電流値から前記ブレーキドラムが冷却して径方向に収縮したときの熱収縮量を推定し、前記制動力調整制御による前記制動力の調整量、および、前記制動力調整制御を実行するタイミングの少なくともいずれかを決定する、請求項１から請求項３のいずれか一項に記載の制動制御装置。
    　     The control unit performs the release control before executing the braking force adjustment control, and estimates the heat shrinkage amount when the brake drum cools and contracts in the radial direction from the current value of the motor, The braking control device according to any one of claims 1 to 3, wherein at least one of an amount of adjustment of the braking force by the braking force adjustment control and a timing of executing the braking force adjustment control is determined. ..
PCT/JP2019/042112 2018-10-29 2019-10-28 Braking control device WO2020090706A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018203007A JP7155876B2 (en) 2018-10-29 2018-10-29 Braking control device
JP2018-203007 2018-10-29

Publications (1)

Publication Number Publication Date
WO2020090706A1 true WO2020090706A1 (en) 2020-05-07

Family

ID=70462061

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/042112 WO2020090706A1 (en) 2018-10-29 2019-10-28 Braking control device

Country Status (2)

Country Link
JP (1) JP7155876B2 (en)
WO (1) WO2020090706A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20220084689A (en) * 2020-12-14 2022-06-21 주식회사 만도 Motor-driven drum brake system and control method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009509867A (en) * 2005-10-05 2009-03-12 ロベルト・ボッシュ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング Method for compensating for cooling of an automatic parking brake and system using this method
JP2016089903A (en) * 2014-10-31 2016-05-23 日立オートモティブシステムズ株式会社 Brake device
JP2017501357A (en) * 2013-12-30 2017-01-12 シャシー ブレイクス インターナショナル ベー．フェー．Ｃｈａｓｓｉｓ Ｂｒａｋｅｓ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｂ．Ｖ． Drum brake device including parking brake operating in duo servo mode, vehicle and assembly method related thereto
JP2017502228A (en) * 2013-12-30 2017-01-19 シャシー ブレイクス インターナショナル ベー．フェー．Ｃｈａｓｓｉｓ Ｂｒａｋｅｓ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｂ．Ｖ． Actuator having irreversible screw nut system, drum brake, and brake device including the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009509867A (en) * 2005-10-05 2009-03-12 ロベルト・ボッシュ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング Method for compensating for cooling of an automatic parking brake and system using this method
JP2017501357A (en) * 2013-12-30 2017-01-12 シャシー ブレイクス インターナショナル ベー．フェー．Ｃｈａｓｓｉｓ Ｂｒａｋｅｓ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｂ．Ｖ． Drum brake device including parking brake operating in duo servo mode, vehicle and assembly method related thereto
JP2017502228A (en) * 2013-12-30 2017-01-19 シャシー ブレイクス インターナショナル ベー．フェー．Ｃｈａｓｓｉｓ Ｂｒａｋｅｓ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｂ．Ｖ． Actuator having irreversible screw nut system, drum brake, and brake device including the same
JP2016089903A (en) * 2014-10-31 2016-05-23 日立オートモティブシステムズ株式会社 Brake device

Also Published As

Publication number Publication date
JP2020069828A (en) 2020-05-07
JP7155876B2 (en) 2022-10-19

Similar Documents

Publication Publication Date Title
KR101960114B1 (en) Actuator system and operating method for an actuator system
JP6622796B2 (en) Method for implementing parking brake operation, control unit, and automated parking brake
US10259439B2 (en) Electric parking brake control and method
KR102113933B1 (en) Brake system and method for operating a brake system
JP7072087B2 (en) Electric brake device
KR102307032B1 (en) Sensor device for a brake system equipped with an electromechanical brake booster and method for determining a braking request specification to a brake system equipped with an electromechanical brake booster
US8991943B2 (en) Automatic parking brake having a slip controller
WO2020090706A1 (en) Braking control device
JP6737733B2 (en) Vehicle braking control device
JP2011042187A (en) Brake control device of motorcycle
JP6531740B2 (en) Brake control device
CN110614986B (en) Method for operating a brake system of a motor vehicle, and control device and brake system
JP6677205B2 (en) Vehicle braking system
JP6540643B2 (en) Brake control device
JP6594002B2 (en) Brake device for vehicle
WO2020004525A1 (en) Brake control device
US9340185B1 (en) Methods and apparatus for braking
JP7218487B2 (en) electric parking brake system
JP6886011B2 (en) How to operate a hydraulic braking system, hydraulic braking system
JP2006137382A (en) Brake fluid pressure control device
JP7327154B2 (en) Braking control device
JP2006027453A (en) Solenoid control valve controlling device and braking liquid pressure controlling device
US11958453B2 (en) Method for operating a brake system, and brake system
CN110091845B (en) Method and device for operating an automated parking brake
WO2024029316A1 (en) Brake device for vehicle

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19877711

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19877711

Country of ref document: EP

Kind code of ref document: A1