Switch mechanism for service disconnect

Abstract

A switch mechanism for electrical service quick connect/disconnect, especially suitable for electric vehicles. The switch mechanism includes a handle for turning a shaft which, through a lost motion connection, rotates a gear in engagement with a rack. The rack moves the switch contacts from a disconnect to a connect position to make and break electrical connection between the vehicle battery pack and the vehicle electrical system. An over center device biases the handle into either a full connect or a full disconnect position once the handle passes an intermediate position. A spring forces a locking detent into a notch on the rack to prevent inadvertent movement of the rack from the connect position, and a cam mounted on the shaft actuates a cam follower portion of the locking detent to move the locking detent out of the notch and allow the rack to move to its disconnect position. Further springs are compressed in response to movement of the contacts to their connect position. Once the locking detent releases the rack, the further springs quickly and positively snap the contacts to the disconnect position. The lost motion connection between the shaft and the gear requires the handle to be moved to an intermediate position before movement of the contacts is initiated in either a connect or disconnect direction. The lost motion connection also allows the snapping movement of the contacts to their disconnect position upon release of the detent.