Self Adjusting Park Brake System
If park brake is released, the jaws (1) are pushed apart (arrows) and will be retained by a locking mechanism. Thus the conduit (2) is disengaged. Now the conduit can move free in longitudinal direction during regular driving and braking.
During engagement of park brake, the conduit (2) slides back to the limiting arrest given through the brake pads. The jaws (1) are pushed back (arrows) and clamp the conduit (2).
Fading through wearing process is prevented because the conduit will be clamped at any position.