A portable gantry crane formed of composite members includes a composite material I-beam. Two or more support members are formed of a composite material and each support member supports the I-beam when the portable gantry crane is in an upright position. Two or more end housings are included, each end housing enclosing a top end of one of the two or more support members and coupled thereto using adhesive. A plurality of latch structures are coupled with the I-beam, each latch structure including a latch, and each end housing having a latch receiver, each latch in combination with a latch receiver allowing one of the latch structures to be releasably fixedly coupled with an end housing. In implementations a plurality of latch structures are coupled with the I-beam, each latch structure having a latch structure enclosure and each latch structure enclosure at least partially enclosing one of the end housings.

A method of upgrading a knuckle-boom crane to a heave-compensating crane includes: removing a knuckle-boom from a main boom; mounting a main boom extension to the main boom for increasing the length of the main boom; and mounting a heave-compensating boom at a far end of the main boom extension such that the heave-compensating boom extends in a downward vertical direction (Z) in operational use of the heave-compensating crane. The heave-compensating boom is configured to be pivotable with respect to the main boom extension in both horizontal directions (X, Y). A heave-compensation system is provided to the knuckle-boom crane, wherein the heave-compensation system compensates for horizontal variations by controlling the orientation of the heave-compensating boom relative to the main boom extension, and compensates for vertical variations by means of a further vertical heave-compensation system, such as a winch-based heave-compensation system.

Utility Task Vehicles comprise a chassis, a truck body mounted to the chassis, a truck bed for holding material, and a hydraulic and/or electrical system. What is presented is a lifting unit for a Utility Task Vehicle that is factory built into the Utility Task Vehicle or an after-market add-on to the Utility Task Vehicle. The lifting unit comprises a cross-bracket mounted to the underside of the chassis and a side rail along one side of the truck body. A rotatable horseshoe hinge is mounted to the side rail. The horseshoe hinge is configured to pivot between a lower position and an upper position. An interchangeable attachment is configured to be installed on the horseshoe hinge. The interchangeable attachment could be, for example, a rock picker, a material lifting bucket, a log and bag loader, a deer skinning pole, or a hoist.

A work machine includes a traveling undercarriage, an upper rotating structure swingably mounted on the traveling undercarriage, a cab mounted on the upper rotating structure, an attachment including multiple work elements and attached to the upper rotating structure, an end attachment attached to the end of the attachment, a first sensor configured to obtain the angles of rotation of the work elements, a second sensor configured to obtain the angle of rotation of the end attachment, and a control device configured to restrict or stop the motion of reducing a distance between the end attachment and the cab in response to determining that the end attachment has entered a predetermined region based on the outputs of the first sensor and the second sensor.

A marine knuckle boom crane includes a crane housing which is rotational relative to a pedestal about a vertical rotation axis and a knuckle boom assembly attached to the crane housing. The knuckle boom assembly includes a main boom, the inner end of which is connected pivotably about a first horizontal pivot axis to the crane housing; and a jib, the inner end of which is connected pivotably about a second horizontal pivot axis to the outer end of the main boom, wherein the jib is pivotable at least between an extended position in which the tip extends mainly forward from the main boom, and a folded position in which the jib is folded back, essentially parallel along the main boom. In order to position the jib with respect to the main boom, a tensioning member is provided extending between the crane housing and a curved extension guide connected to the jib.

The present invention discloses a power transmission control method and device for a crane and the crane. The method includes: setting the maximum working displacement of a secondary element corresponding to each gear of the crane; determining the current gear state and specific gear of the crane; determining the working mode of the secondary element from the gear state, and setting the maximum allowable displacement of the secondary element as the maximum working displacement corresponding to the specific gear.

A vehicle crane having a luffable main jib and an additional jib system arranged on a free end section of the main jib and comprising a first additional jib part and a second additional jib part. To further reduce the weight of the additional jib system and the vehicle crane fitted therewith, and to permit an overall more economical mode of production, the first additional jib part has a rectangular cross-section having four longitudinal chords connected together via transverse struts or/and diagonal struts and the second additional jib part has a triangular cross-section having three longitudinal chords connected together via transverse struts, wherein the two additional jib parts are coupled, or can be coupled, together via a cross-section change adapter.

A portable lifting arm includes a base, a plurality of casters fixed to a bottom side of the base, an arm mounting structure extending upward from a top side of the base, and an arm. The arm includes a first arm segment having a first end and a second end, the first end of the first arm segment being attached to the arm mounting structure, a second arm segment having a first end and second end, the first end of the second arm segment rotationally connected to the second end of the first arm segment, and a power tool rotationally connected to the second end of the second arm segment. A controller in electrical communication the power tool selects between predetermined settings on the power tool based on a position of the first arm segment and the second arm segment relative to the arm mounting structure.

A crane system includes a skid assembly having an operator base and plurality of outrigger assemblies coupled to the operator base that support and lift the base from a first elevation to a second elevation. The crane system also includes a jib crane coupled to the skid assembly. The jib crane includes a pillar assembly coupled to the skid assembly and a boom assembly coupled to the pillar assembly.

The disclosure relates to a work machine, in particular a duty-cycle crawler crane, having an undercarriage which comprises a middle part and at least one crawler carrier which is connected to the middle part and comprises at least one electric traction drive, wherein at least one supply line runs from the middle part to the traction drive and is connected to the latter in a disconnectable manner via a first connection. According to the disclosure, the work machine comprises an electrical interlock loop, which is connected to the traction drive via the first connection, and a mating plug connector module, which is arranged on the undercarriage and has a first mating connection for connecting to the first connection of the supply line and is configured to bridge the interlock loop, which is interrupted by a disconnection from the traction drive, in a current-conducting manner.