Method and apparatus for throwing frangible targets

In a throwing device, said device comprising a pivotal shaft, a body which supports said pivotal shaft, a throwing arm mounted to a first end of said shaft and a crank mechanism affixed to a second end thereof, and a traction spring, said crank mechanism being mechanically coupled to the extendable end of said traction spring, the improvement comprising:

• drive motor means for developing a force for positioning the throwing arm against the tension of the traction spring, said motor means including an electric motor having an output shaft;
• means drivingly coupling said motor means motor output shaft to the pivotal shaft which mounts the throwing arm, said coupling means including a unidirectional clamping means, said clamping means restraining the pivotal shaft to rotation in a first direction only and thereby maintaining the pivotal shaft and the throwing arm in a position commensurate with the traction spring being under tension, said clamping means converting the kinetic energy of the traction spring to potential energy at the end of a throwing operation;
• and
• control circuit means for said drive motor means, said control circuit means automatically de-energizing said drive motor means motor after the throwing arm is spring driven to an overshoot position and locked, at which time said throwing arm is in a desired partially cocked spring tensioned position, and said control circuit means restarting said drive motor means motor whereby the pivotal shaft will be driven from the partially cocked spring tensioned position to an angular position wherein the throwing arm will be released to the influence of the traction spring acting on the crank mechanism for a throwing operation.