Power transmission in double-drum winch

Abstract

Double-drum winch has a power source, a transmission comprised of planetary gear systems alternately actuated by hydraulically actuated clutches for changing the direction of rotation of the output shaft thereof and speed changing reduction gear sets selectively actuated by dog clutches for changing the speed of the output shaft, a drum shaft driven by the transmission, and a hook drum and a boom drum independently rotatable on the drum shaft relative to the drum shaft. The hook drum is provided with hydraulically actuated hook clutch for rotation of the hook drum together with the drum shaft and hydraulically actuated hook brake for arresting the rotation of the hook drum, while the boom drum is provided with hydraulically actuated boom clutch and boom brake of the similar performance. A first hydraulic control system actuated by a first manually operable means controls the clutches of the planetary gear systems and the hook clutch and the hook brake, while a second hydraulic control system actuated by a second manually operable means controls the clutches of the planetary gear systems and the boom clutch and the boom brake thereby permitting the hook drum and the boom drum controlling the hook and the boom, respectively, to be independently actuated in any of the modes of operations by the selective actuation of the first and the second manually operable means, while the dog clutches for the speed changing reduction gear sets are selectively actuated by a third manually operable means, so that only three manually operable means can control the winch for any of the modes of operations at different speeds.