Parking brake application/release, function

D42.10-0053-06

1 Brake lever

2 Cam

3 Tappet

4 Piston

5 Adjusting screw

6 Adjusting nut

7 Secondary piston

8 Piston (primary piston)

9 Inner brake pad

10 Brake carrier

11 Brake disc (internally-ventilated)

12 Outer brake pad

13 Brake caliper

14 Spring

A Contact area

Applying the brake

When the parking brake is operated, the spring brake cylinder is depressurized and the thrust rod is tightened by the spring force. This turns the brake lever (1) and presses the cam (2) onto the adjusting screw (5), via the plunger (3) and piston (4).

The force is transmitted to the adjusting nut (6) via the thread of the adjusting screw (5).

The adjusting nut is pressed against the piston (primary piston) (8) until there is firm contact in the front section of the contact area (A).

Rotation of the adjusting nut is prevented by friction at the contact area (A).

The piston (primary piston) (8) presses the inner brake pad (9) against the brake disc (1) and, due to the reaction force now occurring in the brake caliper, the opposite/outer brake pad (12) is pressed onto the brake disc by the brake caliper (13) with the same force.

Releasing the brake

When the parking brake is released, the spring brake cylinder is pressurized and the brake lever (1) returns to its initial position. At the same time the spring (14) presses the adjusting screw (5) with the adjusting nut (6) into their initial position.



The brake is not adjusted when the parking brake is operated.

The brake is only adjusted automatically, if necessary, when the service brake is operated and the parking brake is released.