US Patent 7770870 Tow ball winch mount

A portable winch system mounted to a standard trailer hitch tow ball of a vehicle permits steep incline pulling angles of the winch without cutting into the neck portion of the tow ball. To achieve a broad range of inclination angles, the cup plate (socket that fits over the tow ball) and/or the ball-locking portion of the winch system includes relieved neck-clearance areas. In some embodiments, the cup plate and/or ball-locking mechanism includes neck contact points that are softer than the material of the tow ball.