Positioning unit for electrical switch actuator

摘要

An electrical circuit switching unit for turning the circuit on and off has a movable bridge contact that is linearly displaced to open and close contacts. The actuation is provided by movement of a lever 61 through an arc to cause a shaft to turn and this has a cam coupling to provide the displacement of the contacts. The lever motion is provided by a roller at the tip that engages an external mechanism and the position of the lever is dependent upon a coupling between a locating element 8 that fits on the shaft 90. The outer surfaces of the lever have toothed rack profiles 62a and these are engaged by mating internal teeth on the locating element.