Abstract: A scissor lift comprises a load support, a lift support and at least one scissor assembly defined between the load support and the lift support, the at least one scissor assembly being driven into an open or a closed position by a drive device that enables movement of the load support relative to the lift support with the opening and closing of the at least one scissor assembly, wherein the at least one scissor assembly is further defined by a pair of arms attached at a pivot, and where the pair of arms further comprises a curved outer surface that engages a portion of a drive device for urging the scissor arms apart and for moving the load support relative to the lift support.

Abstract: The spool shaft comprises a shaft portion, two annular first annular portions arranged on opposite ends of the shaft portion, and an annular second larger diameter portion arranged on the end of the shaft portion positioned remote from a center of the spool. Each of the first annular portions and the second larger diameter portion have an outer diameter that is larger than the outer diameter of the shaft portion. The second larger diameter portion is arranged on an outward side of the first annular portion in the axial direction so as to create a space therein between the first annular portion and second larger diameter portion.

Abstract: A fluid shear actuated brake mechanism includes an outer hub secured to a hoist frame, a main brake disc stack engaged between the outer hub and a hoist drum shaft, an actuator hub helically engaged with the outer hub, and an actuator disc stack engaged between the actuator hub and the shaft. The main disc stack and the actuator disc stack are immersed in a fluid. Rotation of the shaft in a load lowering direction generates fluid shear in the actuator disc stack which rotates the actuator hub in a lowering direction and advances it toward the main disc stack, compressing it and the actuator disc stack. Rotation of the shaft in an opposite load lift direction retract the actuator hub from the main disc stack.

Abstract: A band brake for rotating machinery and equipment, in particular, a band brake for hoists, winches, and similar load lifting equipment. The band brake includes a resilient flexible band disposed about a rotatable drum, a tension bar pivotally coupled to a frame, a positioner attached to the frame and coupled with the tension bar to move the band brake between an engaged position and a disengaged position. The positioner includes a linear actuator, an articulated link assembly, and a magnetic retention assembly.

Abstract: A drawworks having a main drum spool, a main drum shaft which passes through and is rotatably and concentrically supported by the main drum spool, an auxiliary drum spool, respective drum shafts passing through and rotatably and concentrically supported by the drum spools in a manner in which wireline pull from the spools is isolated therefrom, a clutch mechanism rotatably connected to the shafts and brake mechanisms respectively connected to the main drum spool and the auxiliary drum spool outside the working area of the drawworks.

Abstract: A drum winch is replaced with a traction winch module. The traction winch module is mounted on and supported by the existing mooring winch frame of the drum winch. The traction winch module includes a traction frame, a front traction drum, and a rear traction drum. A portion of the drive system from the drum winch may be retained and used to drive the traction winch module. In one embodiment, the traction winch module is designed to mount between pillow blocks from the existing mooring winch frame. In addition, the power train and load-sensing systems from the existing drum winch may be used with the converted traction winch to drive the drive shaft and to provide the converted traction winch with tension information, respectively.

Abstract: A drum hoist or winch in which at least one circular cam lobe mounted eccentrically on an axle overlapping the axle is interconnected with a like circular cam lobe mounted on a second axle by inboard linkage whereby rotation of one axle will rotate the other axle in unison. A hoist drum mounted concentrically with at least one of the axles can thus be rotated in unison with the other axle to wind or unwind one or more cables thereon.A preferred embodiment has three circular cam lobes mounted eccentrically on each axle 120.degree. angularly out of phase with each other with an inboard link plate interconnecting a cam lobe on each axle in rotatable relation.A brake mechanism mounted on an axle has components normally frictionally engaged which rotate as a unit. Sliding frictional motion to slow down and positively brake the hoist to a stop is provided only when rotary speed of the axle exceeds a predetermined speed.

Abstract: A control system for one or more hydraulically driven crane winch drums each having a hydraulically actuated clutch and a brake. Included is a negative braking mechanism having a brake cylinder of the single-acting, spring-return type for normally holding the brake applied by the force of the spring and releasing the brake on fluid pressure actuation. A mode selector valve selectively delivers hydraulic fluid under pressure from two separate sources to the clutch and the brake cylinder in order to condition the winch for a selected one of winching, brake-locking, and free-fall modes. The mode selector valve causes the negative braking mechanism to release the brake in the free-fall mode, so that a positive braking mechanism is also provided to permit the operator to arrest the free fall of the load, or the free running-out of the cable, in an exact position desired.