Actuator for trailer brake - has piston sliding in cylinder acted on by fluid pressure with opposing return springs

摘要

The actuator is used in a trailer brake circuit. It has a cylinder and axial piston with one end outside the cylinder which moves axially under fluid action. An output is associated axially with the piston and can move ahead of it with controlled return in response to a locking detector. The output consists of a bush with a ball cage, over part of it, and two opposing return springs. One of these is stronger than the other, the stronger sprinq working with the cage.