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.

Telescoping boom systems, devices, and methods are provided in accordance with various embodiments. For example, some embodiments include zero dead band telescoping boom systems, devices, and methods. Embodiments in general include hard stop preloading mechanisms for telescoping booms with multiple tube segments. Some embodiments provide components that facilitate the deployment sequencing of the multiple tube segments along with facilitating preloading of the multiple tube segments of a telescoping boom. The tools and techniques provided may be integrated into the multiple tube segments rather than being provided as a separate system. Some embodiments allow for precise deployment of the multiple tube segments of the telescoping boom systems, devices, and methods.

A telescopic pipe includes a base pipe having a base inner pipe rotated by external force, and a base outer pipe arranged to receive the base inner pipe; a connecting pipe having a connecting inner pipe coupled to the base inner pipe to be extendable to transfer rotational force, and a connecting outer pipe screw-coupled to the inner circumferential surface of the base outer pipe to be extendable; and a finishing pipe including a finishing inner pipe coupled to the connecting inner pipe to be extendable and to be rotated, and a finishing outer pipe that is interlocked by means of rotation of the finishing inner pipe and is screw-coupled to the inner circumferential surface of the connecting outer-pipe to be extendable, wherein the connecting outer pipe is interlocked by the rotational force of the extended finishing outer pipe and thus is extended and retracted along the base outer pipe.

A balanced cantilevered feeding apparatus for coupling with a jib, and a complementary method for its operation, configured to facilitate depositing and removing of a load through an opening in a building. The apparatus includes two spaced apart upright hoisting assemblies disposed on the jib, and a fly beam hoisted, balanced, and selectively positioned along a lateral axis by the two hoisting assemblies. A load securing member is mounted on a cantilevered extension portion of the fly beam, wherein the member extends beyond one of the two hoisting assemblies toward the building, and a counterweight is connected to the fly beam in the vicinity of another of the two hoisting assemblies.

A balanced cantilevered feeding apparatus for coupling with a jib, and a complementary method for its operation, configured to facilitate depositing and removing of a load through an opening in a building. The apparatus includes two spaced apart upright hoisting assemblies disposed on the jib, and a fly beam hoisted, balanced, and selectively positioned along a lateral axis by the two hoisting assemblies. A load securing member is mounted on a cantilevered extension portion of the fly beam, wherein the member extends beyond one of the two hoisting assemblies toward the building, and a counterweight is connected to the fly beam in the vicinity of another of the two hoisting assemblies.

A telescoping jib of a mobile crane includes sections that telescope out of a jib housing from a transport position into an operating position. A guying system has successively connected tension rods extending from the jib housing to at least one of the extended telescoping jibs by at least one guying support. The mobile crane provides a lighter construction and improved road handling, and an increased load capacity for unchanged telescoping jib measurements. To this end, a guide holder arranged on the jib housing receives the tension rods in the transport position and, in the operating position, at least one movable tension rod on one of the guying supports is respectively securely connected to the outer end of a telescoping section head in an articulated manner and can be secured to a holding mechanism on the opposite end on an adjacent guying support of an adjacent telescoping section head.

A work machine includes: an actuator that extends and retracts a telescopic boom; an electric drive source that is provided in the actuator and drives using power supplied from a power source; an operating unit that operates based on power of the electric drive source; and a joint that has a drive-side element fixed to a first transmission shaft that rotates on the basis of the power of the electric drive source and a driven-side element fixed to a second transmission shaft connected to the operating unit, the joint being able to take a transmission state in which both the drive-side element and the driven-side element rotate and a non-transmission state in which only either the drive-side element or the driven-side element rotates.

A crane including a main boom having a first end portion and a second end portion, and being supported by a support structure via a hinged connection whereby the main boom is pivotable in a vertical plane. A pivoting assembly is arranged below the main boom, wherein the pivoting assembly includes an electric motor-and-winch assembly, a sheave assembly, and one or more drive wires extending between the motor-and-winch assembly and the sheave assembly.

A balanced cantilevered feeding apparatus for coupling with a jib, and a complementary method for its operation, configured to facilitate depositing and removing of a load through an opening in a building. The apparatus includes two spaced apart upright hoisting assemblies disposed on the jib, and a fly beam hoisted, balanced, and selectively positioned along a lateral axis by the two hoisting assemblies. A load securing member is mounted on a cantilevered extension portion of the fly beam, wherein the member extends beyond one of the two hoisting assemblies toward the building, and a counterweight is connected to the fly beam in the vicinity of another of the two hoisting assemblies.

The present invention relates to a single-cylinder plug pin type telescopic arm, a crane and a telescopic method thereof. The single-cylinder plug pin type telescopic arm includes a basic arm and at least one telescopic arm sleeved in the basic arm, wherein coaxial center holes are formed in the tails of the telescopic arms, and a telescopic oil cylinder is arranged in the center holes; the telescopic oil cylinder includes a cylinder rod and a cylinder barrel, at least two cylinder heads are fixedly sleeved on the outer side of the cylinder barrel in the longitudinal direction, and at least three arm pin holes are formed in each of the basic arm and the telescopic arms in the longitudinal direction. The single-cylinder plug pin type telescopic arm provided by the present invention adopts one telescopic oil cylinder and at least two cylinder heads, each cylinder head is adapted to lock and unlock the telescopic oil cylinder and any telescopic arm, the telescopic arms are extended out or retracted in a relay transmission manner to achieve the extension and retraction of the single-cylinder plug pin type telescopic arm, the length of the oil cylinder is shortened, the cylinder diameter and the rod diameter of the oil cylinder are decreased, the cost of the oil cylinder is lowered, the upperstructure weight is reduced, the lifting capacity is improved, and there are more crane design spaces.