Advics Co., Ltd.

Aisin Seiki Kabushiki Kaisha

Aisin Seiki K.k.

Tetsuaki Tsuzuki

Kentaro Yuasa

Yusuke Oshio

Michiharu Nishii

Takashi Watanabe

Masanobu Fukami

Akitaka Nishio

Masatoshi Hanzawa

Shiro Monzaki

Masahiro Inden

Tetsuya Kuno

Kazuma Kondo

Shunsuke Murata

Jin Yamada

Keiichi Shino

An electric parking brake device generates pressing force by pressing friction materials against a brake disc by causing a piston to move by motor operation. A control device executes: parking processing wherein the motor increases the pressing force to an initial pressing force higher than a lower-limit pressing force; and re-drive processing wherein the motor is driven and the pressing force increased at a re-drive time, which is a predetermined time after the end of execution of parking processing. During parking processing, the control device uses one among the initial pressing force and the predetermined time, in addition to a pressing force decrease characteristic corresponding to an assumed temperature set for use in calculation, as a basis to calculate the other of the initial pressing force and the predetermined time such that the pressing force becomes equal to or less than the lower-limit pressing force at the re-drive time.

Electric parking brake device

Electric parking brake devices are configured such that a parking lever is driven by an electric actuator. The electric actuator is provided with: an electric motor drivable in a forward/reverse direction and operationally controlled by a motor control unit according to rotational loads; a conversion mechanism capable of converting a rotational motion into a linear motion, moving the parking lever from a return position toward an operating position through forward rotation of the electric motor, and moving the parking lever from the operating position toward the return position through the reverse rotation of the electric motor; and a load applying mechanism (a stopper and a disc spring assembly) for applying a predetermined rotational load to the electric motor by driving a constituent member of the conversion mechanism after the parking lever is moved from the operating position to the return position through the reverse rotation of the electric motor.

A brake temperature detection device is configured detect brake temperature more accurately. In a situation in which the temperature in the vicinity of the brake has risen above the atmospheric temperature, indicated by a value read off of the detection signal of the temperature sensor, for example when traveling in congested traffic, a value to correct atmospheric temperature is determined, and atmospheric temperature is corrected on the basis of that atmospheric temperature correction value. Subsequently, brake temperature is calculated on the basis of the corrected air temperature. As a result of this configuration, it is possible to have the calculated brake temperature approach the actual brake temperature. This makes it possible to detect brake temperature more accurately.

Brake temperature detection device and electric parking brake control device

Provided is an electric parking brake device in which a parking lever is driven by an electric actuator. The electric actuator includes: an electric motor which can be rotationally driven in a normal/reverse direction and of which an operation is controlled by a motor control unit in accordance with rotational loads; a converting mechanism which can convert a rotational movement into a linear movement and which can move the parking lever from a returning position to an operating position in accordance with normal rotation of the electric motor and which can move the parking lever from the operating position to the returning position in accordance with reverse rotation of the electric motor; and a load applying mechanism (a stopper, a friction material) which drives components of the converting mechanism and which applies predetermined rotational loads to the electric motor, in a state where the parking lever is moved from the operating position to the returning position in accordance with reverse rotation of the electric motor.

A parking brake control device performs a releasing control with good precision by more precisely maintaining clearance between a friction-applying member and a friction-applied member. During a releasing control, a timing at which a braking force generated by an electric parking brakedrops to zero is detected based on a change in a motor current, and a second releasing operation time is set according to the magnitude of the motor current at the time the braking force drops to zero. This makes it possible for the second releasing operation time to be set in accordance with fluctuations in a motor load due to temperature changes or the like. Therefore, a clearance between a brake pad and a brake disc can be kept constant according to the motor load.

Parking brake control device

A vehicle motion control device reduces noise resulting from operation of a vacuum booster when an automatic pressure control is performed by properly controlling the energization of a linear solenoid of a booster actuator. An automatic hydraulic pressure generator is controlled in accordance with the vehicle motion condition and a hydraulic pressure control valve device is controlled to perform the automatic pressure control. A target electric current of the linear solenoid for actuating the vacuum booster is instantaneously increased to a starting target value which corresponds to an electric current value immediately before starting the operation of the vacuum booster and which is less than a maximum value of the target electric current, and then is gradually increased approximately to the maximum value of the target electric current.

Vehicle motion control device

An electromagnetic valve of the present invention includes a housing 11,13, a fluid passage 12 provided in the housing 11,13, a valve member 18,21 for opening and closing the fluid passage 12, and a one way valve 25 having a valve member 26 and a valve seat 19b. The one way valve 25 is provided at one end of the fluid passage 12. The one way valve 25 is installed integrally within the housing 11,13 to facilitate installation in a small space.

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Gamagori, Japan

Tetsuaki Tsuzuki