Torque limiting coupling with driving members and switching cams having complementary faces

A torque limiting coupling for driving agricultural implements or machinery comprising:

• a coupling hub and a coupling sleeve relatively rotatably supported thereon;
• driving members movably arranged in inwardly directed, circumferentially distributed recesses of said coupling hub, said driving members including heads which, in the torque transmitting position, each engage a corresponding recess in the opposed inner face of the coupling sleeve and in a switched-off position, disengage therefrom, the torque transmitting face of the heads extending parallel to a rotational axis of the coupling sleeve and coupling hub, a base of the driving members being provided with two switching faces one switching face providing support in the torque transmitting position, and the other switching face providing support in the switched-off position;
• a switching cam including at least first and second adjacent switching faces loading said driving members, said cam being spring-loaded in the direction of the torque transmitting position and movable transversely relative to the respective driving member arranged in the recesses in the coupling hub, one of the switching faces of the cam and driving members, which serve torque transmitting purposes, extending at an angle relative to the central axis of the respective driving member, said angle being greater than the angle of the second switching face for the switched-off position, and the switching faces being designed so as to correspond to one another, and said torque transmitting face and the switching faces of the driving members being arranged so as to circumferentially extend in the same direction.