Toyota Jidosha Kabushiki Kaisha

Advics Co., Ltd.

Takahiro Shiraki

Takashi Watanabe

Masatoshi Hanzawa

Naoki Yabusaki

Shinichiro Yukoku

Yoshikazu Tachiiri

Tsuyoshi Ando

Shunsuke Murata

Yukio Tamada

A brake temperature detection device: acquires a kinetic-energy based temperature rise, which is an increase in an amount of brake heat that occurs when kinetic energy generated in a running vehicle is converted into thermal energy by braking; acquires a braking-energy based temperature rise, which is an increase in an amount of brake heat that is calculated from an amount of work done when a brake's friction material is pressed against a friction target material; determines state of slope of a road surface on which the vehicle is running; and detects a brake temperature in accordance with an increase in an amount of brake heat generated in braking. The brake temperature detection device selects, based on the state of slope, either the kinetic-energy based temperature rise or the braking-energy based temperature rise as the increase in the amount of brake heat generated in braking and achieves brake temperature detection.

Brake temperature detection device and electric parking brake control device

A vehicle parking brake system for a vehicle including: a non-rotary body; a rotary drum; brake shoes; an anchor member disposed between anchor-member-side end portions of the respective brake shoes; a transmitting member interconnecting transmitting-member-side end portions of the respective brake shoes; and a parking-brake operating apparatus configured to predict a torque application direction in which a torque is to be applied to the wheel during stop of the vehicle, and to press the brake shoes against an inner circumferential surface of the rotary drum, by moving a primary one of the brake shoes that serves as a primary shoe upon application of the torque to the wheel, in a direction away from the anchor member, without moving a secondary one of the brake shoes that serves as a secondary shoe upon application of the torque to the wheel.

Parking brake system

A friction brake device for a vehicle includes: a hydraulic brake unit including a piston member for pressing a friction member by advancement; an electric brake unit including a nut member being relatively movable in a piston movement direction with respect to the piston member by a motor and for pressing the piston member by advancement; a piston return mechanism including a biasing member for making biasing force, oriented in a retreat direction, elastically act on the piston member in accordance with a relative advancement amount of the piston member with respect to the nut member; and a controller for controlling the motor. The controller determines whether an adjustment permission condition associated with a wear amount of the friction member is satisfied. When the condition is satisfied, the controller allows the motor to perform a relative position adjustment of the nut member with respect to the piston member.

Brake device

A vehicle brake control device is configured to correct deformation failure of a seal member and inhibit insufficient pullback of a pressing member caused by insufficient deformation of the seal member. Within a time period from a start of a lock operation to an end of the release operation, a W/C pressure is automatically increased and insufficient deformation of a seal member is corrected. It is thus possible to generate a large restoring force by the seal member when pulling back a piston, and the piston can be pulled back based on the restoring force. The piston is therefore sufficiently moved, and it is possible to inhibit insufficient piston pullback. Further, it is possible to cause a brake pad to be separated from a brake disc by a predetermined distance, and it is possible to inhibit a feeling of drag of a brake from being imparted to a driver.

Vehicle brake control device

An EPB-ECU is an electric parking brake control device which generates a braking force by driving an electric motor to press pads and to a disc rotor. The EPB-ECU includes a current supply unit for supplying a motor current to the electric motor and stopping the supply of the motor current when the motor current reaches a predetermined target current value, a supply time measurement unit for measuring a supply time of the motor current, a waiting time setting unit for setting a waiting time from when the supply of the motor current is stopped to when the supply of the motor current is restarted next time on the basis of the measured motor current supply time, and a control unit for instructing the current supply unit to supply the motor current according to the set waiting time.

Electric parking brake control device

A brake apparatus for restraining rotation of a wheel of a vehicle by application of a brake that is to be activated for causing a friction member, to be pressed against a brake rotor, through a piston that is movable in an axial direction of the piston. The brake apparatus includes: (a) a power drive device; (b) a driven member that is to be moved, by the power drive device, relative to the piston in the axial direction; and (c) an engaging portion that is provided in one of the driven member and the piston, such that the piston is held in engagement with the driven member through the engaging portion. The engaging portion is disposed such that, during release of the application of the brake, the piston is movable rearwardly while being held in engagement with the driven member through the engaging portion.

Brake apparatus

During the standstill state maintenance control executed by an electric parking brake system, the moving force-based target tension Frefb is determined based on the inclination angle of a vehicle and the shift position each time the predetermined program is executed, and the tentative target tension Fref(n) in the current routine is set to a smaller value from among the moving force-based target tension Frefb and the maximum value Fmax. The control target tension Fref(n)* is set to a larger value from among the control target tension (the final target tension) Fref(n&#x2212;1)* in the immediately preceding routine and the tentative target value Fref(n). Even if the tentative target tension Fref(n) is smaller than the control target tension Fref(n&#x2212;1)*, the control target value Fref(n)* is not set to a value smaller than the control target tension Fref(n&#x2212;1)*.

Electric parking brake system and method for controlling the electric parking brake system

In an electric parking brake system, the moving force-based target tension is set based on the inclination angle of a vehicle and the shift position, and the slack compensation amount is determined based on the inclination angle of the vehicle and the shift position. The control target tension is set to a smaller value from among the slack-based target tension, which is the sum of the moving force-based target tension and the slack compensation amount, and the maximum value of the output power that can be produced by an electric motor. The electric motor is controlled such that the tension of the cable matches the control target tension (the slack-based target tension, in most cases).

In an electric parking brake system including a tension control unit that controls the friction member pushing force in a brake by controlling the tension of a cable, the target tension is set to a larger value when a vehicle is maintained at a standstill on a downhill slope than when the vehicle is maintained at a standstill on an uphill slope.

In an electric parking brake device, an equalizer is pivotably carried at its center part on a nut which is caused by an electric motor to perform linear reciprocating motion, and parking brakes are operated by respective cables which are connected respectively to the opposite end portions of the equalizer. Stop members are provided for preventing the pivot movement of the equalizer in the state that the equalizer is held returned by the operation of the electric motor to an extreme position on the side of the parking brakes. The stop members may be composed of a first stop member for preventing the equalizer from being pivoted in one direction and a second stop member for preventing the equalizer from being pivoted in the other direction, or may be constituted by a member of one piece structure for preventing the equalizer from being pivoted in both directions.

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Toyota, Japan

Takahiro Shiraki