Segment of an articulated arm made of composite material, with an elongated shape defining a longitudinal axis, and having a box-like cross section. The segment includes a first end portion, configured for the pivoting of a further segment, a second intermediate portion configured for the pivoting of an actuation member, and a third end portion. The first, second and third portions are made in a single body. The second intermediate portion includes a protruding zone defined by a first side and by a second side converging with respect to each other to define a top. Pivoting elements are provided in the protruding zone for the pivoting of the actuation member between the protruding zone and the first end portion. The first and the second side defining the protruding zone are filleted to substantially rectilinear adjacent tracts of the first and third end portions.

Segment of an articulated arm made of composite material, with an elongated shape defining a longitudinal axis, and having a box-like cross section. The segment includes a first end portion, configured for the pivoting of a further segment, a second intermediate portion configured for the pivoting of an actuation member, and a third end portion. The first, second and third portions are made in a single body. The second intermediate portion includes a protruding zone defined by a first side and by a second side converging with respect to each other to define a top. Pivoting elements are provided in the protruding zone for the pivoting of the actuation member between the protruding zone and the first end portion. The first and the second side defining the protruding zone are filleted to substantially rectilinear adjacent tracts of the first and third end portions.

Provided is a jib connection structure capable of connecting a jib base end engagement part and a jib connection shaft even when a boom undergoes natural extension, and capable of restraining a jib from swinging sideways in a state where the jib is projected. This jib connection structure includes: jib connection shafts projecting horizontally toward both sides from a boom tip end part; and jib base end engagement parts respectively provided to bifurcated jib base end parts. Each jib base end engagement part is U-shaped into which the jib connection shaft can be fitted, and is provided with an insertion hole into which a pin for preventing the jib connection shaft from slipping out is inserted. When the jib base end engagement part and jib connection shaft are connected, a gap is formed between the pin and jib connection shaft. When a jib is projected, the gap becomes smaller.

Provided is a jib connection structure capable of connecting a jib base end engagement part and a jib connection shaft even when a boom undergoes natural extension, and capable of restraining a jib from swinging sideways in a state where the jib is projected. This jib connection structure includes: jib connection shafts projecting horizontally toward both sides from a boom tip end part; and jib base end engagement parts respectively provided to bifurcated jib base end parts. Each jib base end engagement part is U-shaped into which the jib connection shaft can be fitted, and is provided with an insertion hole into which a pin for preventing the jib connection shaft from slipping out is inserted. When the jib base end engagement part and jib connection shaft are connected, a gap is formed between the pin and jib connection shaft. When a jib is projected, the gap becomes smaller.

A telescoping crane boom having a rotary locking mechanism. A motor drives a rotating element about an axis parallel to the axis of the crane boom. The rotation of the rotating member causes a pin to selectively lock and unlock sections of the telescoping crane boom.

A boom extension and contraction mechanism for a crane apparatus includes: a flow passage switching mechanism that switches a flow passage of the hydraulic oil between the cylinder-to-boom connection switching cylinder side and the boom member connection switching cylinder side; a hose reel configured to reel out a hydraulic hose as a telescopic cylinder is extending, and to reel off the hydraulic hose as the telescopic cylinder is contracting; a cable used to supply power and transmit a signal between a swivel base and a boom; and a cord reel configured to reel out the cable as the telescopic cylinder is extending and to reel off the cable as the telescopic cylinder is contracting. The code reel and the hose reel are arranged on the base in a direction in which the boom extends and contracts.

A boom assembly for a lift device includes a plurality of telescoping boom sections. The plurality of telescoping boom sections include a base boom section, a mid boom section, and a fly boom section. The plurality of telescoping boom sections define an inner volume. The boom assembly also includes a push tube coupled to the base boom section and a support member positioned within the inner volume. The support member includes sidewalls having an inner surface and an outer surface. The boom assembly also includes a power track positioned within the inner volume that includes a plurality of movable links, a first supported portion that interfaces with at least one of the inner surface of the support member and a surface of the push tube, and a second supported portion that interfaces with the outer surface of the support member.

A boom for supporting a drilling and bolting tool includes a first portion including a first end and a second end, a longitudinal axis extending between the first end and the second end; a second portion including a proximal end and a distal end, the proximal end supported for translational movement relative to the first portion in a direction parallel to the longitudinal axis, the distal end configured to support the drilling and bolting tool; an actuator for moving the second portion relative to the first portion parallel to the longitudinal axis; and a fluid passage for conveying pressurized fluid between the first end of the first portion and the drilling and bolting tool adjacent the distal end of the second portion, the fluid passage positioned within the first portion and the second portion.

There is provided a boom extending and retracting apparatus that can improve the convenience of the telescopic boom while reducing the burden on the operator. The boom extending and retracting apparatus of the crane chooses the mode of the fluid circuit between the normal fluid circuit and the differential fluid circuit to slide a plurality of boom members by one telescopic cylinder. After the operating lever is turned to an extension side and the controller starts extending the telescopic boom using the differential fluid circuit, when the operating lever is turned to the extension side again via the neutral position, the controller chooses the normal fluid circuit to extend the telescopic boom using the normal fluid circuit.

A multi-component lattice mast section comprises a longitudinal axis, a plurality of chord elements extending along the longitudinal axis, a plurality of connection bars interconnecting in each case two adjacent chord elements, a lattice mast cross-sectional surface area with a lattice mast width and a lattice mast height, the lattice mast cross-sectional surface area being oriented perpendicular to the longitudinal axis, and at least two detachably interconnectable lattice mast assemblies, with each of the lattice mast assemblies having a lattice mast assembly width smaller than the lattice mast width and/or a lattice mast assembly height smaller than the lattice mast height, and with the connection bars being firmly connection to a chord element in a working arrangement.