Abstract: An improved circuit breaker includes a case, a movable arm, and a bumper retained within a receptacle formed on the case. The bumper is retained in the receptacle by a number of spaced ribs that engage certain portions of the bumper yet permit deformations of other portions of the bumper into an expansion region. By employing a bumper made of a material having a low coefficient of restitution, deformation of the bumper tends to dissipate the energy of a movable arm impacting the bumper. The bumper can be installed, removed, and replaced substantially without requiring the use of an adhesive. The movable arm engages the bumper on a corner of the bumper to provide the bumper with an effectively progressive spring rate.

Abstract: A door interlock assembly is for a draw-out circuit breaker assembly. A draw-out circuit breaker is housed within an enclosure including a door and includes a poleshaft operable between first and second positions corresponding to separable contacts being opened and closed, respectively. The door interlock assembly includes a pivot member coupled to the poleshaft and a door latch interconnected to the pivot member by a linkage, such as a threaded drive rod. The door latch pivots such that a first end thereof engages and locks the door of the enclosure when the poleshaft moves to the second position. An optional mechanical sensor assembly adapted to trip the circuit breaker when the door is positioned in any position other than closed, is also disclosed.

Abstract: A manual operator assembly is provided for an interlock assembly. The interlock assembly includes a motor assembly that is locked in one of two positions by a brake assembly. The brake assembly is electronically controlled, but also includes a brake release pedal. The manual operator assembly includes a lever which is coupled to a shaft which is further coupled to a cam. When the lever is rotated, the cam engages the brake release pedal so that the interlock assembly may be operated manually.