Automobile brakes are divided into two-way self-energizing hoof brakes, double-collar hoof brakes, follower hoof brakes, and double slave hoof brakes according to their different structures. Its braking efficiency is reduced in turn, and the disc brake is very low; but the stability of the braking efficiency is sequentially increased, and the disc brake is very high. It is for this reason that disc brakes are commonly used. However, in order to improve its braking efficiency, a brake booster system must be added to make it more expensive, so low-end cars generally use the front disk and rear drum type. The equipment used to increase the friction coefficient between the tire and the ground is mainly divided into drum type and disc type, which is also used for parking. The drum type has a rapid braking force, but the braking force decreases rapidly after heating; the disc type The braking technology is large, and the braking force is not large enough for the drum type, but it can still maintain a good braking effect after heating, and the advanced disc brake has 6 brake pumps, which can make good braking results. Therefore, modern cars use disc brakes.