Clamp for captive tube in electromagnetic circuit breakers

Abstract

An electromagnetic circuit breaker having a frame is supported in fixed position relative to the housing and provides a platform for a bobbin on which is wrapped the electromagnetic coil of the breaker. One flange of the bobbin rests on the frame platform. The other flange supports a flange at the end of a non-magnetic tube containing the movable magnetic core to support the tube and the core in position extending through the center of the coil. The tube is closed by the pole piece which on overload attracts the armature of the breaker. A clamping member is supplied to hold the flange of the tube against the flange of the bobbin and to clamp the entire structure against the frame securely so that it will not move. The clamping means is arranged to contact a wall of the housing having a component generally parallel to the flange. The clamping means is preferably composed of a sheet metal member bent away from the plane of the flange to a point of contact with the housing then bent to conform to the housing. Preferably the other end of the clamping means engages the frame and may be conveniently done by providing a slot in the frame into which a key end of the clamping means is inserted in a position to afford a fulcrum for leverage using the housing wall to impose clamping pressure on the flange.