Method and apparatus for controlling speed and direction of a vehicular towing winch and improvements in a towing winch

A winch and control system comprising:

• an input member coupled to a bidirection variable speed fluid motor,
• an output member coupled to a drum, and
• transmission means between the output and input members, said transmission means including two stages of planetary gearing having portions thereof coupled to two sets of friction locking members for selectively operatively coupling the portions of the two stages for providing the four functions of a low-speed range, a high-speed range, freewheel and drum locked, said transmission means further including a fixed case, said friction locking members being totally within said case and including a first set of friction elements operable to releasibly lock the case to one stage of the planetary gearing for providing one gear ratio to said output member, a first actuator biased into a locking position for locking the friction elements and movable into a release position for releasing the friction elements, a second set of friction elements operable to releasibly lock a second stage of the planetary gearing to said first stage for providing a second gear ratio to the output member, a second actuator movable independently of said first actuator and biased into a locking position for locking the second set of friction elements and movable into a release position for releasing the second set of friction elements, and hydraulic control means for selectively moving only said first actuator for providing said one gear ratio, only said second actuator for providing said second gear ratio, both said actuators for providing freewheel movement of said output member, and no movement for locking both portions of said gear means to said case for locking said output member to the case.

A method of controlling speed, direction, braking and freewheeling conditions in a towing winch mounted on a towing vehicle having a transmission within a casing, comprising:

• powering a multiple stage planetary gear winch transmission having an input member and an output member by a variable speed, reversible fluid input drive circuit,
• selectively hydraulically controlling the locking of one stage of the transmission to drive the output member of the transmission at a first speed,
• selectively hydraulically controlling the locking of another stage of the transmission to said one stage independently of said first hydraulic controlled locking to drive the output member of the transmission at a second speed,
• selectively hydraulically controlling the locking of both said stages of the transmission simultaneously to said interior of said casing for locking the output member of the transmission independently of the input member, and
• selectively releasing all of said stages of the transmission for freewheeling the output member of the transmission.