The present disclosure refers to a mobile telescopic hydraulic crane, which may include at least one service opening in a terminal portion of a telescopic section adjacent to at least one hydraulic connector, wherein said at least one service opening is configured to allow access for a hand tool from the outside of the telescopic section to establish or disassemble a hydraulically sealed connection between a flexible hydraulic pipe and associated hydraulic connector within said telescopic arm. The at least one service opening allows for a quick and simple replacement of each hydraulic pipe within the telescopic secondary arm without significantly reducing the carrying capacity and reach of the crane.

A lightweight and high-rigidity telescopic boom in which strain during manufacturing is suppressed is disclosed. In a telescopic boom, a plurality of booms forms a telescope structure, and the telescopic boom includes a boom fixing mechanism that fixes a top boom disposed relatively inside at a predetermined position with respect to a first intermediate boom disposed relatively outside. The boom fixing mechanism includes a boom fixing pin that is provided to the top boom and advances and retreats with respect to the first intermediate boom, a fixing boss that is provided to the first intermediate boom and into which the boom fixing pin is inserted and extracted, and a gap maintaining member that is provided to the fixing boss and protrudes outward to maintain a gap between the first intermediate boom and a second intermediate boom disposed further outside.

This crane is configured by being provided with: a telescopic boom having an inside boom element and an outside boom element that overlap each other in an extendable and contractible manner; an extension/contraction actuator that displaces one boom element among the inside boom element and the outside boom element in the extending and contracting directions; at least one electric drive source provided in the extension/contraction actuator; a first coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the extension/contraction actuator and one of the boom elements; and a second coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the inside boom element and the outside boom element.

A hydraulic crane comprising: —a rotatable column (7); —a crane boom system (10) comprising two or more liftable and lowerable crane booms (11, 13); and —an electronic control device (25), which is configured to prevent an execution of crane boom movements that would make the lifting moment of the crane exceed the maximum allowed lifting moment of the crane, and to continuously establish position information as to the prevailing position of the load suspension point (P) of the crane boom system. When the lifting moment of the crane has reached a limit value at a given level below the maximum allowed lifting moment, the electronic control device is configured to prevent the execution of any combination of crane boom movements that would increase the horizontal distance between the load suspension point and said vertical axis of rotation and at the same time allow the execution of any combination of crane boom movements that keeps said horizontal distance unchanged or reduces said horizontal distance.

A pin actuator assembly for a telescoping boom includes a locking head having a base, an operating plate operably coupled to the base, one or more cylinder pins and/or one or more section lock arms movable in response to movement of the operating plate relative to the base. The pin actuator assembly also includes an actuator operably coupled to the operating plate and configured to move the operating plate relative to the base. The actuator includes an electric motor and a drive arm. The electric motor is configured to drive the drive arm between an extended drive arm position and a retracted drive arm position. The pin actuator assembly further includes a motion mitigator having a housing, a rod movable relative to the housing and operably coupled to the actuator, a first biasing member coupled between the rod and the housing and a second biasing member coupled between the rod and the housing.

An embodiment relates to a mobile crane having an articulated body and an elongate boom attached to the body, the boom being for carrying a load when the crane is stationary and while the crane is mobile. The boom is articulated to provide a movement for lifting and lowering an end of the boom, and the boom is further articulated to provide a movement of the boom laterally. A further embodiment relates to controlling swing of a load carried at the end of a boom of a mobile crane by varying lateral orientation of the boom.

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.

A personal safety system for lifting material or supporting person therefrom includes a base and a mast rotatably coupled to the base. The mast has a plurality of mast sections that telescope relative to each other along an axis such that the mast is movable into and between a lowered configuration and an extended configuration. A jib is coupled to the mast and a cable is coupled to the jib such that a cable is configured to couple to the material or the person such that the system is capable of lifting the material or supporting the person. An attachment device coupled to the base is configured to permit a vehicle to couple to the system via the attachment device.

This crane is provided with: a telescopic boom that can be extended; an extension device for extending the telescopic boom; a hydraulic pressure source provided in the extension device; a cylinder connection mechanism connected to the hydraulic pressure source and switching between the states of connection and non-connection with the telescopic boom on the basis of the supply and discharge of hydraulic oil; a first oil path for connecting the hydraulic pressure source and the cylinder connection mechanism; a first valve that is provided on the first oil path and switches the supply and discharge state of the hydraulic oil with respect to the cylinder connection mechanism; and a second oil path that bypasses the first valve and connects the hydraulic pressure source and the cylinder connection mechanism.

A mining or construction vehicle comprising an extendable boom comprised of a first and a second telescopic section extending in a longitudinal direction, wherein the first telescopic section is arranged to be connected to the mining or construction vehicle and a hydraulic device is arranged to be connected to a mounting device at a free end of the second telescopic section, wherein a hydraulic cylinder is arranged in connection to the extendable boom to govern extension of said extendable boom. Hydraulic conduit for supply of hydraulic fluid to the hydraulic device on the mounting device are arranged through the length of the extendable boom.