Abstract: A crane having a hydraulically actuated jib system, at least one cylinder for actuating the jib system and an apparatus for monitoring the pressure in the cylinder, which indicates the crane loading, wherein the feed flow of hydraulic fluid to the cylinder is controllable by varying the cross-section of a valve, and a signal is produced in dependence on the variation in pressure in relation to time which is detected in the cylinder or the variation in the loading of the piston guided in the cylinder in relation to time, which signal actuates the drive for adjusting the valve cross-section in the direction of a reduction in the detected variation in pressure or loading.

Abstract: A forklift with four wheels mounted on a chassis and a gantry which carries the forks and can be folded down longitudinally for transporting the forklift. The chassis of the forklift consists of two parts joined together by a hinge. The two chassis parts pivot relative to each other about a horizontal transverse axis and about a vertical axis, allowing for concurrent movement in the perpendicular axes of the chassis.

Abstract: A loading crane that can be mounted on a lorry has a jib composed of several arms telescopically nested into each other. A hydraulic unit composed of piston and cylinder is arranged between successive arms. When an arm is extended, a stop arranged on the previous arm actuates a valve entrained with the extended arm, which opens a hydraulic supply for the arm that follows the extended arm. Such valve is arranged at the closed end of a hydraulic cylinder of the arm that follows the extended arm.

Abstract: A multistage telescopic boom or jib, in particular for a loading crane on a truck, has hydraulic units each including a piston and a cylinder arranged between the successive, telescopically nested arms. A pipe projects axially from the bottom of the cylinder into the chamber of the cylinder, sealingly extending into the hollow piston rod when the piston is retracted and sealing the chamber of the cylinder from an inner chamber of the hollow piston rod. In order to ensure an automatic extension sequence of the telescopic arms, the inner chamber of each hollow piston rod is linked to the cylinder chamber of the next outer hydraulic unit by a preferably rigid line, and the inner chamber of each hollow piston rod communicates with the cylinder chamber of the same hydraulic unit when the piston is fully extended.

Abstract: A hydraulically extendable and retractable truck support or stabilizer jack is pivoted upwards about a vehicle-mounted trunnion or axis. A free end of the jack is hinged to a telescopic rod which can be retracted to a limited extent and which is mounted to pivot on a pivot element or swivel member which in turn pivots about a vehicle-mounted trunnion or axis in the direction of the jack until it reaches a vehicle-mounted stop.

Abstract: The supporting frame (1) for the loading crane of a truck (2) is transported by a trailer, whose swingability is blocked in the operating position of the loading crane. In the operating position the truck (2) is rigidly connected to the supporting frame (1) via hydraulic units (5,8).