Abstract: An electrical starting winding switch for electrical motors having a calibrated single make and break contact with an unusually high opening force for the higher electrical values encountered in high density electrical motors while maintaining a much lower value of uniform contact closing force during the speed-responsive actuation of the switch.

Abstract: A speed-responsive electrical switch assembly consisting of a centrifugally-actuated switch operating unit customarily mounted on a rotatable shaft and having orbitally movable weights engageable with the surface presented by a switch unit to cause make and break operation of the electrical switch contacts. The radial centrifugally-induced inboard and outboard movement of the weights themselves in engagement with the surface of the switch unit, preferably an angularly inclined cam surface, serves to modulate the axial or longitudinal switch-operating, spring-induced displacement of the weights toward or away from the electrical switch unit and thus permits greater latitude in manufacturing and assembly tolerances and with improved switch operating characteristics while still maintaining prior art standards of precision switch control and uniformity of switch action.