Abstract: A fluid motor is connected to a winch at a remote distance from a hydrostatic pump; a scavenge pump is driven by a motor powered by part of the main drive fluid and maintains a lubrication level of fluid also taken from the main drive fluid in the transmission sump at a sufficient level to prevent air contamination of the main drive fluid.

Abstract: A transmission suitable for use in a winch, wire line drum, or other vertical hoisting device is provided with independently actuatable disc clutches for actuating various planetary gear sets to vary the speed through at least three speed ranges. The gear sets and clutches are immersed in oil, and control means are provided to energize the clutches always in sets of two so that only one disc clutch remains disengaged to minimize the viscous drag of the disengaged clutch in the oil. The planetary sets and clutches form the transmission between an input shaft and an output drive assembly. In the preferred embodiment, a final multiple-speed drive assembly is provided to increase the three-speed ratios to six-speed ratios to obtain a wide speed range.

Abstract: A drive train for a winch from a continuously rotating input source to an intermittently rotated drum in which the drive train is through a clutch, then to a shaft, then through a continuously driven internal brake which forms a part of the drive train from the shaft, then to the drive train to the drum, with the shaft being provided with a one-way clutch so that the brake automatically is engaged for lowering the load by reversing the drum. A free-spool circuit is provided which can be operated only in the brake release position for safety and is operated off the brake release hydraulic control fluid pressure. A static or manual pump control fluid circuit is provided for operating the clutch, brake and/or free spool. A combination driving clutch and drag clutch are energized by opposite directional movement of a single piston for coupling an input to an output or stopping movement of the output.

Abstract: An input shaft is provided with circumferentially spaced ramps which confront opposed ramps on a coaxially aligned ramp shaft. The ramp shaft is provided with a sun gear which can rotate only through a one-way clutch and a plurality of brake discs. The sun gear drives a drum through a planetary drive system. The ramps each are provided with a shoulder. Balls are trapped between the ramps. Rotation of the input shaft in a hoisting direction drives the ramp shaft bypassing the brake through the one-way clutch. Thus the drum is rotated by the torque through the balls and shoulders. The brake discs are set by springs so that the load remains braked when hoisting is stopped. In the power down condition the input shaft rotates relative to the ramp shaft so that the balls move along the ramps spreading the shafts and compressing the springs so that the brake discs are released.