Modular bi-directional overrunning wheel clutch

In combination, a walk-behind machine having an engine, an axle rotatably driven by said engine, and a pair of ground engaging wheels, one said wheel located at each end of said axle;

• and a modular, bi-directional wheel clutch unit adapted to be assembled to the driving axle of a walk-behind machine including:
• a rotatable wheel-driving hub detachably fixed to a said wheel and including a casing portion;
• a clutch cage disposed in said casing portion and surrounded thereby, said clutch cage having a plurality of circumferentially-distributed openings;
• a cam element detachably fixed to said axle and disposed in said casing portion, said cam element surrounded by said clutch cage and having a plurality of discrete surfaces thereon;
• and
• a plurality of rollers rotatably disposed within said casing portion and within said clutch cage openings, said rollers located between said casing portion and said cam element discrete surfaces, said rollers having an engaged position wherein said cam element and said hub are in binding engagement through said rollers and said hub is rotatably driven by said cam element, and a disengaged position wherein said hub is freely rotatable relative to said cam element;
• wherein said wheel clutch unit is modular and self-contained, said unit being selectively attachable and detachable as a unit to and from said driving axle of said walk-behind machine.

A modular, bi-directional wheel clutch unit adapted to be assembled to the driving axle of a walk-behind machine, said unit comprising:

• a rotatable casing;
• a clutch cage disposed in and surrounded by said casing;
• a rotatably driven cam element disposed in said casing and surrounded by said clutch cage, said cam element having a plurality of discrete surfaces thereon;
• and
• a plurality of rotatable elements rotatably disposed within said casing and within said clutch cage, said rotatable elements located between an interior surface of said casing and said cam element discrete surfaces, said casing being selectively driven by said cam element through selective engagement of said casing with said cam element through said rotatable elements;
• wherein said wheel clutch unit is modular and self-contained, said unit being selectively attachable and detachable as a unit to and from said driving axle of said walk-behind machine.

In combination:

• a walk-behind machine including:
• an engine;
• an axle driven by the engine;
• and
• a pair of ground-engaging wheels, one said wheel at each end of said axle;
• and
• a modular, self-contained bi-directional wheel clutch unit selectively attachable and detachable as a unit to and from the driving axle of a walk-behind machine, said unit comprising:
• a rotatable casing;
• a clutch cage disposed in and surrounded by said casing, said clutch cage having a plurality of openings along a circumference of said clutch cage;
• a rotatably driven cam element disposed in said casing and surrounded by said clutch cage, said cam element having a plurality of discrete surfaces thereon;
• and
• a plurality of rollers rotatably disposed within said casing and within said clutch cage openings, said rollers located between an interior surface of said casing and said cam element discrete surfaces, said casing being selectively driven by said cam element through selective engagement of said casing with said cam element.