JPS6311540B2 - - Google Patents

Abstract

PURPOSE:To enhance the wheel parking brake effect of a car when it is parked, by providing a spring chamber in a caliper itself and utilizing its spring brake action so as to force pads to be directly pressed to a brake disc. CONSTITUTION:Pads 5, 6, oppositely facing to each other, are respectively mounted to the front end face of a piston 3, fitted into a cylinder 2 of a caliper 1, and to a pawl part 7 in the end of the caliper 1, while a brake disc 4 is arranged between the both pads 5, 6. In the above device, the caliper 1, in its side where the cylinder 2 is provided, integrally forms an air chamber 8, and a piston plate 9 is fitted to be longitudinally movable mounted in the inside of said chamber 8. In this way, the brake device, when it is used as a wheel parking brake at parking of a car, forces the brake disc 4 to be held between the both pads 5, 6 by discharging a pressure of air introduced into a front chamber 12 of the air chamber 8 and advancing the piston plate 9 by a spring 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic disc brake device.

Conventional hydraulic disc brakes with wheel parking brake mechanisms are mainly power screw type and wedge mechanism type, in both of which the spring chamber is separated from the disc brake body and power is transmitted through a linkage. Therefore, there was a problem with efficiency. There are also spring brake calipers that have a separate spring brake caliper.
This had the problem of being disadvantageous in terms of weight.

The present invention provides a spring chamber in the caliper itself, and uses the spring brake operation of the spring chamber to press the pad directly against the brake disk to apply the wheel parking brake when parking, thereby solving the above-mentioned conventional problem. This is the solution.

Embodiments of the present invention will be described below with reference to the drawings.
A caliper 1 has a cylinder 2 into which fluid pressure is introduced, and a piston 3 is fitted into the cylinder 2 so as to be able to move forward and backward. A pad 5 is attached to the front end surface of the piston 3, and a pad 6 is attached to the claw portion 7 at the tip of the caliper 1 so as to face the pad 5. A brake disc 4 is arranged between the pads 5 and 6. In the above-mentioned conventional general hydraulic disc brake, the present invention integrally forms an air chamber 8 on the side where the cylinder 2 of the caliper 1 is provided, and a piston plate 9 inside the air chamber 8.
It is fitted so that it can move forward and backward. An air chamber 8 defined by this piston plate 9
A spring 10 for moving the piston plate 9 forward is installed in the rear chamber 13, and a spring 10 is installed in the front chamber 12.
is provided with an air pressure supply/discharge port 11 connected to an air pressure control device. Reference numeral 14 is a ventilation hole for allowing the interior of the rear chamber 13 to breathe as the piston plate 9 moves forward and backward.

Furthermore, a push rod 15 is integrally provided on the back surface of the piston 3, projecting into the front chamber 12 of the air chamber 8 and abutting against the front surface of the piston plate.

When the present invention having the above structure is used as a service brake, air pressure is introduced into the front chamber 12 of the air chamber 8 as shown in FIG. By introducing hydraulic pressure into the cylinder 2, the pads 5, 6 are pressed against the brake disc 4 to perform normal braking.

Also, when used as a wheel parking brake when parking, the front chamber 1 of the air chamber 8
Discharge the air pressure introduced into 2. As a result, the spring 10 moves the piston plate 9 forward, pushes the push rod 15, and mechanically clamps the pads 5, 6 against the brake disc 4 to maintain the braking state.

When the wheel parking brake state shown in FIG. 2 is released, as shown in FIG. 3, air pressure is introduced into the front chamber 12 of the air chamber 8 again to move the piston plate 9 backward and compress the spring 10. do. As a result, the pushing force of the push rod 15 is released, and the clamping pressure applied to the brake disc 4 by the pads 5 and 6 is released.

As described above, according to the present invention, the spring brake mechanism provided on the caliper itself directly operates the wheel parking brake during parking, so the advantage is that the wheel parking brake using the hydraulic disc brake can be obtained extremely efficiently. There is.

[Brief explanation of the drawing]

The drawings are cross-sectional views showing an embodiment of the present invention, in which FIG. 1 is a diagram when the service brake is activated, FIG. 2 is a diagram when the wheel parking brake is activated, and FIG. 3 is a diagram when the wheel parking brake is released. It is. 1... Caliper, 2... Cylinder, 3... Piston, 4... Brake disc, 5, 6... Pad, 8... Air chamber, 9... Piston plate, 10... Spring, 15... Push rod.

Claims (1)

[Claims] 1. In a hydraulic disc brake in which a brake disc is compressed by a pair of pads by the operation of a piston of a fluid pressure cylinder provided in a caliper, an air chamber is provided in the caliper,
A piston plate that is moved forward by a spring and moved backward by air pressure is fitted in this air chamber, and a push rod that protrudes into the air chamber from the back of the piston that operates the pad and comes into contact with the piston plate is fitted. Hydraulic disc brake device.