Hitachi Automotive Systems, Ltd.

Mazda Motor Corporation

Tatsuro Kobune

Kenichiro Matsubara

Wataru Yokoyama

Kimio Nishino

Shinji Seto

Hirotaka Oikawa

Takayasu Sakashita

Shigeyuki Uehara

Michiharu Okada

A brake device having an electric parking brake function, capable of appropriately performing stepwise increase control for a clamping force. A control unit including a computing circuit (), a memory (), and each motor drive circuit () of a parking brake control device () includes a stepwise increase control unit configured to increase the clamping force generated by brake pads () to a disc rotor () in a stepwise manner. When start of contact between the disc rotor () and the brake pads () caused by feeding of power from the parking brake control device () to an electric motor (B) is detected based on a motor current from a current sensor unit (), the stepwise increase control unit performs control for repeatedly feeding and stopping power to the electric motor (B) to increase the clamping force in a stepwise manner in accordance with a predefined processing procedure.

Brake device

Provided is a brake device capable of maintaining pads and a rotor in a desired positional relationship. When receiving a release request within a time period from start of execution of an application request to detection of contact between brake pad and a disc rotor, a parking brake control device inhibits execution of the release request, and executes the release request after detection of the contact between the brake pad and the disc rotor. Further, when receiving the application request within a time period from start of execution of the release request to detection of separation between the brake pad and the disc rotor, the parking brake control device inhibits execution of the application request, and executes the application request after detection of the separation between the brake pad and the disc rotor.

A brake apparatus comprising: a caliper having a piston configured to move a brake pad to be pressed on a disc rotor rotating with a wheel; a thrust retaining mechanism located in the caliper to thrust the piston and maintain braking force exerted by the thrust piston; an electric motor mounted on the caliper to operate the thrust retaining mechanism; and a controller configured to apply electric current to the electric motor in response to an application command or a release command, thereby perform control according to the commands, wherein the controller, upon receiving a release command, configured to operate the electric motor to reduce braking force exerted by the piston by performing current maintenance control which continuously applies electric current to the electric motor and switching control which successively switches between a larger and a smaller amount of electric current applied to the electric motor.

Brake apparatus

An object of the present invention is to obtain a brake system that can generate appropriate braking force without influence of temperature. A brake system includes: a piston that presses pressing members; a motor that moves the piston; a current detection unit that detects current flowing in the motor; a storage unit that stores a correspondence relation between idle running current and motor stopping current; a motor stopping current setting unit that sets the motor stopping current using the storage unit and the idle running current; and a control unit that stops to supply the current to the motor when the current flowing in the motor reaches the motor stopping current. The correspondence relation is set so that the rate of change of the motor stopping current relative to the idle running current becomes smaller when the idle running current is small than that when it is large.

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Atsugi, Japan

Tatsuro Kobune