Automatic spring powered battery charging device

In a battery charging device of the type having a frame, a coil spring mounted on said frame for coiling and uncoiling movement, a drive gear mounted for rotation on said frame and coupled with said coil spring in a manner to rotate in response to uncoiling of the spring, a mechanical linkage coupled with and driven by said drive gear upon rotation thereof, and battery charging means driven by said linkage and operable to apply charging current to the battery, a shaft supported for rotation on said frame and carrying said drive gear thereon, a spring winding gear mounted on said shaft for rotation relative thereto and coupled with said spring in a manner to effect winding thereof in response to rotation of the spring winding gear, power means for effecting rotation of said winding gear, the improvement comprising:

• an actuator ring mounted on said shaft for movement independently thereof, said ring presenting a peripheral notch therein;
• lost motion means coupling said drive gear and said actuator ring with one another in a manner providing lost motion therebetween;
• a switch mechanism for energizing and deenergizing said power means, said switch mechanism including a switch arm having a free end engageable against the periphery of said actuator ring with said free end of the switch arm entering said notch upon movement of the actuator ring to a preselected rotative position corresponding to an unwound condition of said spring, said switch mechanism being operable to deenergize said power means when said free end is engaged against the periphery of said actuator ring and to energize said power means when said free end is disposed in said notch;
• and
• means for removing said free end of the switch arm from said notch in response to rotation of said spring winding gear sufficient to effect a wound condition of the spring.