Abstract: A compressible stop member for use on a crane includes: a housing having a first sealed end, a second end, a first cylindrical surface and a second cylindrical surface; a free piston slidably contained within the housing in a sealing engagement with the first cylindrical surface; a compressed gas chamber in the housing between the free piston and the first sealed end; and a rod comprising a cylindrical portion with a diameter less than the diameter of the second cylindrical surface and a rod support portion that separates a first liquid chamber comprising the volume inside the housing between the free piston and the rod support portion from a second liquid chamber comprising the volume between the rod support portion and the second end of the housing. Also, the rod support portion includes at least one flow channel allowing liquid to flow between the first and second liquid chambers.

Abstract: A compressible stop member for use on a crane includes: a housing having a first sealed end, a second end, a first cylindrical surface and a second cylindrical surface; a free piston slidably contained within the housing in a sealing engagement with the first cylindrical surface; a compressed gas chamber in the housing between the free piston and the first sealed end; and a rod comprising a cylindrical portion with a diameter less than the diameter of the second cylindrical surface and a rod support portion that separates a first liquid chamber comprising the volume inside the housing between the free piston and the rod support portion from a second liquid chamber comprising the volume between the rod support portion and the second end of the housing. Also, the rod support portion includes at least one flow channel allowing liquid to flow between the first and second liquid chambers.

Abstract: A crane having an upper works rotatably mounted on a lower works and a boom pivotally mounted on the upper works includes a hydraulic boom hoist cylinder and a hydraulic circuit for controlling the hydraulic boom hoist cylinder. The hydraulic cylinder is pivotally connected to a mast on the upper works and pendently connected to the boom. The boom hoist cylinder preferably comprises two double-acting hydraulic cylinders. The hydraulic circuit includes a closed loop pump and a hydraulic controller connecting the closed loop pump and the double-acting cylinders such that fluid from the pump can be directed either to extend or retract the cylinders, with the hydraulic fluid exiting the cylinders being directed to return to the pump.

Abstract: A crane having an upper works rotatably mounted on a lower works and a boom pivotally mounted on the upper works includes a hydraulic boom hoist cylinder and a hydraulic circuit for controlling the hydraulic boom hoist cylinder. The hydraulic cylinder is pivotally connected to a mast on the upper works and pendently connected to the boom. The boom hoist cylinder preferably comprises two double-acting hydraulic cylinders. The hydraulic circuit includes a closed loop pump and a hydraulic controller connecting the closed loop pump and the double-acting cylinders such that fluid from the pump can be directed either to extend or retract the cylinders, with the hydraulic fluid exiting the cylinders being directed to return to the pump.

Abstract: An apparatus for powering the crawlers of a crawler vehicle. The apparatus comprises one or more hydraulic drive motors mounted on the vehicle, car body, a track drive gear box mounted on the crawler, and one or more mechanical drive shafts connected between the hydraulic drive motors and the track drive gear box to transmit power from the drive motors to the track drive gear box. The mechanical drive shafts are disconnectable from between the hydraulic drive motors and the track, drive gear box so as to permit the disassembly and removal of the crawlers from the car body.

Abstract: A crane having an upper works rotatably mounted on a lower works, a boom pivotally mounted on the upper works, and a hydraulic boom hoist cylinder to control the angle of the boom. The crane further comprises a mast and a hydraulic cylinder pivotally connected to the upper works. The connection of the mast to the upper works is at a location separate from, and at an elevation below, the elevation of the connection of the hydraulic cylinder to the upper works. The hydraulic cylinder is pivotally connected to the mast and pendently connected to the boom.

Abstract: A multi-coupling device for connecting multiple hydraulic lines between first and second portions of a crane is disclosed. The device is for use where the crane portions are not aligned with a tolerance as small as that necessary for connecting the hydraulic line couplings. The multi-coupling device comprises a first plate rigidly holding the first part of each of the couplings in a spaced relationship, the first plate being rigidly fixed to a first crane portion; a second plate rigidly holding the second part of each of the couplings in a spaced relation corresponding to the spaced relation of the first coupling parts; a mounting device which mounts the second plate on a second crane portion with a freedom of movement at least as great as the tolerance in alignment between the first and second crane portions; and alignment means for aligning the first and second plates.