| 摘要 |
PROBLEM TO BE SOLVED: To provide a vehicle drum brake system capable of preventing the degradation of drag performance of a brake.SOLUTION: A vehicle drum brake system comprises: a pair of pistons accommodated in a wheel cylinder to be able to move forward and backward, one of the pistons facing an open end of a shoe on one direction side of a vehicle, and the other piston facing an open end of a shoe on the other direction side of the vehicle; a parking lever pivotally supported by an open end portion of the shoe on the other direction side of the vehicle; a brake strut provided between a base portion of the parking lever and the open end portion of the shoe on one direction side of the vehicle, having one end coupled to the base portion of the parking lever, and having the other end coupled to the open end portion of the shoe on one direction side of the vehicle; a foot brake pedal supplying a brake fluid to the wheel cylinder and braking a drum; and a brake shoe adjustment device rocking the parking lever in an actuation direction before vehicle runs, slidably moving slide surfaces of the shoe on one direction side of the vehicle and the shoe on the other direction of the vehicle on an inner circumferential surface of the drum (step S5), rocking the parking lever in an opposite direction to the actuation direction right after vehicle starts running, and separating the shoe on one direction side of the vehicle from the inner circumferential surface (step S7).SELECTED DRAWING: Figure 9 |
