Drum brake is mainly composed of bottom plate,brake drum,brake shoes,wheel cylinder(brake sub-pump),return spring and positioning pin and other components.The bottom plate is installed on the fixed position of the axle,which is fixed and immobile.It is equipped with brake shoes,wheel cylinder,return spring and positioning pin,and bears the rotating torque when braking.Each drum has a pair of brake shoes with friction linings.The brake drum is mounted on the hub and rotates with the wheel.It is made of cast iron and is shaped like a round drum.
When the vehicle is braking,the wheel cylinder piston pushes the brake shoe to press the brake drum,which is decelerated by friction,forcing the wheel to stop rotating.
In the brake,the rotating part is the brake drum,which is connected with the wheel with bolts and rotates together with the wheel;The fixing part is the brake bottom plate 10,the brake bottom plate is mounted on the flange of the rear car bridge end,and the brake bottom plate is equipped with brake shoe 3 and other brake parts and wheel brake cylinder assembly 9,etc.
In the brake drum,the lower end of both sides of the brake shoe 3 and the brake friction disc 12 is inserted in the corresponding groove of the brake bottom plate 10,the upper end is close to the piston of the wheel brake cylinder 9,and the upper supporting point adjacent to the hand brake push rod 2 supporting point,stuck in the push rod 2.The upper part of the brake shoe is pulled tight by the spring 5 and 4,and the lower part is pulled tight by the spring 8.The brake shoe is pressed on the brake bottom plate 10 by the limiting screw,the limiting spring seat 6 and the limiting spring.
Brake drum manufacturer points out that when braking,step down the brake pedal,brake fluid pressure into the wheel brake wheel cylinder 9,so that the piston moves outwards,push the brake shoe 3 and brake friction plate 12 to press outwards on the brake drum,so that the wheel decelerates until it stops rotating.
During the hand brake,pull the hand brake handle,hand brake cable pulls the hand brake lever 7 forward,and push the left and right brake shoes to the brake drum through the lever action of push rod 2;When the hand brake handle is stuck,the brake shoe presses tightly on the brake drum,which becomes the parking brake of the car.
The gap between the brake shoe and the brake drum is automatically adjusted by the adjustment wedge 1 installed on the push rod 2.The lower end of the adjustment wedge is equipped with an adjustment spring 13.The adjustment spring pulls the adjustment wedge to automatically adjust the gap.(The article comes from the network,for reference only)
