Adjustable magnetic tripping device and circuit breaker including such device

摘要

Adjustment of the static position of the armature of a solenoid or relay-type structure is used to adjust the trip level. An armature stop rod extends through an opening in the structure and is bent over to adjust the length of the stop rod between the frams opening an the active part of the armature. A compact structure is achieved by winding the device coil on a plastic bobbin which provides a bearing for the armature at one end, and an extension through which the adjustment portion of the stop rod extends. This permits ready adjustment after assembly, even when the device spring is arranged around the armature inside the bobbin.