Electromechanical switch actuator

An electrochemical key switch actuator for use as a crew switch of mass transit vehicle comprising:

• (a) an actuator body adapted to be entirely within a wall of the vehicle and having
• a substantially planar front surface adapted to be mounted within the vehicle wall;
• a rear surface adapted to be mounted to a rotary switch located within said vehicle wall;
• a cylindrical hole extending from said front surface of the actuator body through to said rear surface of the body;
• and
• a rearward cavity in communication with said hole and recessed in said rear surface of the body, the longitudinal axes of said rearward cavity and said cylindrical hole being offset such that only a portion of said cylindrical hole and a portion of said rearward cavity are in overlapping relationship;
• (b) a key actuator shaft mounted for rotation in said cylindrical hole, said key actuator shaft having
• a male portion having a unique configuration adapted to mate with a correspondingly configured female end of an operating key,
• a female portion adapted to mate with said rotary switch, and
• an intermediate portion of substantially constant cross-sectional dimensions having a partially peripheral slot formed therein;
• (c) retaining means situated in said rearward cavity and mechanically affixed to said actuator body, said retaining means mating with said peripheral slot to preclude axial movement of said shaft and rotation thereof beyond predetermined angular positions;
• (d) a substantially planar face plate mounted to the front surface of said actuator body, said face plate having a central opening overlying said cylindrical hole, such that the female portion of said operating key can be inserted into and mated with the male portion of said key actuator shaft and removed therefrom only in predetermined positions.