Brake system

Abstract

To suppress noise generated in an electric actuator while suppressing dragging in an electric parking brake operated by the electric actuator.SOLUTION: In a brake system, release control of an electric parking brake is performed in a form that varies on the basis of a brake temperature. Due to this configuration, while dragging is suppressed, a release control amount of a drive member after pressing force becomes smaller than a set value is set to an appropriate amount. As a result, a waste operation of an electric actuator can be suppressed so as to make length of an operating time appropriate, and operating noise generated in the electric actuator can be suppressed.SELECTED DRAWING: Figure 5

Claims

1. In a brake system equipped with a brake control unit that controls an electric parking brake, The brake control unit includes a release control unit that performs release control to release the electric parking brake in different manner based on the brake temperature, which is the temperature of the electric parking brake, The aforementioned electric parking brake uses a drive member to press a friction engagement member against the brake rotating body. The release control includes a first release control which controls the drive member to retract until the pressing force of the electric parking brake becomes less than a set value, and a second release control which controls the drive member to retract further after the pressing force has become less than a set value. A brake system in which the release control unit includes a portion that determines the release control amount, which is the amount of retraction of the drive member in the second release control, to be a smaller value when the brake temperature is high than when it is low.

2. A brake system comprising a brake control unit for controlling an electric parking brake, The brake control unit includes a release control unit that performs release control to release the electric parking brake in different manner based on the brake temperature, which is the temperature of the electric parking brake, The aforementioned electric parking brake uses a drive member to press a friction engagement member against the brake rotating body. The release control includes a first release control which moves the drive member backward until the pressing force of the electric parking brake falls below a set value; a second release control which, after the pressing force falls below the set value, moves the drive member backward by an amount determined based on the brake temperature; and a third release control which, after the second release control is completed, moves the drive member backward further. A brake system in which the release control unit performs the third release control when the brake temperature reaches or exceeds a set temperature after the completion of the second release control, or when it is estimated that the brake temperature will reach or exceeds the set temperature, and does not perform the third release control when the brake temperature is lower than the set temperature, or when it is not estimated that the brake temperature will reach or exceed the set temperature.

3. The electric parking brake includes a friction engagement member and a pressing device that presses the friction engagement member against the brake rotating body. The brake system according to claim 1 or 2, wherein the friction engagement member is common to the service brake.

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