The positive pressure applied to the
Brake Disc is produced by pre-compression of the disc spring. If the disc spring fails in the system such as fatigue, yielding, breaking, etc., causing the disc spring stiffness to decrease, the positive pressure exerted by the disc spring on the brake disc will be reduced, which will disable the brake. Disc springs are an important factor influencing the normal operation of disc brakes.
The preload of the disc spring and the positive pressure of the brake disc and the brake shoe depend on the preload of the disc spring during design. With the use of the disc brake, the brake shoe wears and the brake shoe is loosened. The gap between the disc and the brake disc becomes larger, and the preload of the disc spring is reduced, and the positive pressure of the disc spring preload is less than the design value, causing the brake positive pressure to drop. Therefore, during the use of the disc brakes, there are strict requirements for the adjustment of the brake shoe clearance.
Piston motion resistance In the design of disc brakes, the piston motion resistance is generally taken as 10% of the brake positive pressure. However, in actual work, the friction between the piston and the hydraulic cylinder and the card cylinder cause the motion resistance to be larger than the theoretical value. The increase of the motion resistance will cause the braking torque to decrease. If the card cylinder appears, the brake will completely fail. Happening.