What is the reason for the braking drag of the air brake system

The brake drag of the air brake system means that after the car has traveled for a certain distance, the brake drum will heat up, which will increase the sliding distance of the car. It may be caused by the lack of free travel of the brake pedal of the car, or it may be caused by the brake lever sticking The position or the return spring cannot -> cannot return to the position.

　　

The parking brake is to give the car a resistance when the car is parked, that is, the car's hand brake or the parking gear in the automatic transmission, to lock the car's drive shaft or rear wheels. The braking system used by the car is an electronic braking system. The electronic control method is used to realize the parking brake, and the electronic hand brake is realized by the electronic control method. The working principle of the parking brake is the same as that of the mechanical hand brake. The dragging phenomenon of the hydraulic braking system of the car is that after the brake pressure plate is lifted during the driving process of the car, individual wheels still have a braking effect, which makes it difficult for the car to start, and the driving resistance is large, which requires the brake dragging of individual tires Make repairs.