Patent ID: 8420961

Claim:
An assembly mounted on electrical enclosures or panels, comprising: a pushbutton assembly; a mounting block assembly connected to the pushbutton assembly, the mounting block assembly having means for securing the switch assembly to a wall of the electrical enclosure or panel; and an interlock contact block attached to the mounting block assembly, the interlock contact block having a housing and at least one normally open interlock contact enclosed within the housing, the interlock contact being biased to a closed position by an interlock arm in physical contact with the wall of the electrical enclosure or panel when the pushbutton switch assembly is installed thereon, the interlock arm including a self-adjusting member for automatically adjusting the length of the interlock arm within a predetermined adjustment range to compensate for a variation in the thickness of the wall on which the pushbutton switch assembly is installed, the self-adjusting member having a proximate end that is slidably received into a cavity defined in a distal end of the interlock arm, the self-adjusting member having a distal end that engages an inside surface of the wall when the pushbutton switch assembly is installed thereon, the interlock arm being movable such that if proper operation of the interlock contact block by the pushbutton assembly is prevented, the interlock contact will automatically resume its normally open position.