Under the action of brake fluid pressure, the pistons of the working brake cylinder move out of the cylinder and press
brake shoes to the working surface of the brake drum. After releasing the brake pedal, under the influence of the tension springs, the brake shoes press the pistons into the cylinder and move away from the brake drum. The working brake cylinder has a device for automatic adjustment of the gap between the brake shoes and the brake drum, limiting the recession of the pistons into the cylinder. Thanks to this, the optimal gap between the brake shoes and the brake drum is maintained
The rear brakes are also part of the parking brake system.
The device, diagram of the rear brake mechanism: 1 - lower brake shoe tension spring; 2 - front brake shoe; 3 - front shoe pressure spring; 4 - spacer bar; 5 - upper tension spring; 6 - working brake cylinder; 7 - brake mechanism shield; 8 - axial pin of the spacer lever; 9 - spacer lever; 10 - rear brake shoe; 11 - parking brake cable tip
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