YIELDABLE, CONSTANT ENGAGEMENT, FRICTION COUPLING, (E.G.,SLIP CLUTCH) IN DRIVE FOR CABLE PULLING DRUM:
Apparatus for pulling on a load hauling cable including a driven drum, the drive for the drum includes a coupling having at least two members which rotate around a common rotational axis and have a surface in constant contact with that of the other cooperating member, the members normally rotate together at the same rotational speed when transmitting power to the drum due to the friction created by the contact of their surfaces, however, if the torque on one of the members exceeds an acceptable amount, or the amount of force tending to push the contact surfaces of the members toward each other is reduced, the contact surfaces will slip relative to each other.
