Abstract: A vehicle crane having a telescoping jib, comprising a basic box with retractable and extendible inner boxes and a securing and locking unit that comprises a first adjusting cylinder and a second adjusting cylinder which are each designed as unilaterally acting hydraulic cylinders with a first spring element and a second spring element as well as a first line and a second line, where the first adjusting cylinder moves locking bolts between operating states of unbolted and bolted and the second adjusting cylinder moves driving bolts between operating states of secured and released. In the event of a malfunction, the first adjusting cylinder moves to the bolted operating state and the second adjusting cylinder moves to the released operating state.

Abstract: Device and process for braking rotating and/or slewing gears of work machines comprising at least one dynamic service brake for decelerating a rotating and/or pivotal movement of the rotating and/or slewing gear, and at least one static holding brake (16), by means of which the rotating and/or slewing gear can be locked in one position, wherein at least one sensor (14) is assigned to the dynamic service brake (11a) and/or to the static holding brake (16), said sensor detecting the current movement of the rotating and/or slewing gear, and the sensor (14) being connected to a controller (13, 19) that detects an actuation of the dynamic service brake (11, 11a) said controller actuating the static holding brake (16) when in case of continued rotating and/or pivoting movement of the rotating and/or slewing gear when a dynamic service brake (11a) is still actuated.

Abstract: Device and process for braking rotating and/or slewing gears of work machines comprising at least one dynamic service brake for decelerating a rotating and/or pivotal movement of the rotating and/or slewing gear, and at least one static holding brake (16), by means of which the rotating and/or slewing gear can be locked in one position, wherein at least one sensor (14) is assigned to the dynamic service brake (11a) and/or to the static holding brake (16), said sensor detecting the current movement of the rotating and/or slewing gear, and the sensor (14) being connected to a controller (13, 19) that detects an actuation of the dynamic service brake (11, 11a) said controller actuating the static holding brake (16) when in case of continued rotating and/or pivoting movement of the rotating and/or slewing gear when a dynamic service brake (11a) is still actuated.

Abstract: A hydraulic control circuit for the overcontrol of a hydraulic system which controls a drive, in particular for controlling a hydraulic motor (5) for driving a slewing gear of a crane superstructure, wherein the pressure lines (3.9, 3.10) for the hydraulic motor (5) are connected by means of a supply piston (3.2) to a hydraulic pump (2) or a tank (1), and the pressure lines (3.9, 3.10) are each assigned pilot valves (3.4, 3.3), shuttle valves (3.8, 3.7) and directional control valves (3.6, 3.5). The shuttle valves (3.7, 3.8) are connected by means of control lines (3.11, 3.12) to an activatable proportional pilot valve (6), such that the separately activatable directional control valves (3.5, 3.6) can thus be activated by means of said pressure, which is built up by the pilot valve (6).

Abstract: A crane having a telescoping boom whose sections, are arranged in a base boom that can telescope individually, in and out, after disengaging locking pin connections that are secured in the respective moved out or moved in positions by locking pins. A guide profile head is arranged at an end remote of the articulation of the safety locking unit to the inner end of the base boom. To lengthen the boom without substantially changing the telescopic system itself, the guide profile head is detachably fastened to the safety locking unit. An additional guide frame, whose length is dimensioned corresponding to the length of the telescoping boom that has been expanded by additional sections inserted in the telescoping boom, is mounted in place of the guide profile head, and that a guide profile head can be arranged at the free end of the guide frame.

Abstract: A crane having a telescoping boom whose sections, are arranged in a base boom that can telescope individually, in and out, after disengaging locking pin connections that are secured in the respective moved out or moved in positions by locking pins. A guide profile head is arranged at an end remote of the articulation of the safety locking unit to the inner end of the base boom. To lengthen the boom without substantially changing the telescopic system itself, the guide profile head is detachably fastened to the safety locking unit. An additional guide frame, whose length is dimensioned corresponding to the length of the telescoping boom that has been expanded by additional sections inserted in the telescoping boom, is mounted in place of the guide profile head, and that a guide profile head can be arranged at the free end of the guide frame.

Abstract: The invention relates to a hydrostatic drive system having a pump (1) and at least one consumer (6) that can be connected alternately to the pump (1) and to a tank (3) by means of a directional control valve (4) that can be actuated by control signals (15, 16), in order to control the motion of a positive or a negative load (9) at the consumer. Provision is made to this effect that there is disposed in the line (13) of the negative connection of the consumer that leads via the directional control valve (4) to the tank (3) a pre-charge valve (5, 51, 60) that can be placed under a pressure that can be controlled via a programmable logic unit (31) when controlling a positive load.

Abstract: A hydraulic control circuit for the overcontrol of a hydraulic system which controls a drive, in particular for controlling a hydraulic motor (5) for driving a slewing gear of a crane superstructure, wherein the pressure lines (3.9, 3.10) for the hydraulic motor (5) are connected by means of a supply piston (3.2) to a hydraulic pump (2) or a tank (1), and the pressure lines (3.9, 3.10) are each assigned pilot valves (3.4, 3.3), shuttle valves (3.8, 3.7) and directional control valves (3.6, 3.5). The shuttle valves (3.7, 3.8) are connected by means of control lines (3.11, 3.12) to an activatable proportional pilot valve (6), such that the separately activatable directional control valves (3.5, 3.6) can thus be activated by means of said pressure, which is built up by the pilot valve (6).