The disclosure relates to a ballast device for fastening to a crane having first and second ballast elements. The first ballast element has first connection means for a releasable fastening to the crane, while both ballast elements are releasably connected to one another via second connection means. According to the disclosure, the first ballast element comprises an assembly device having abutment elements to which an abutment means can be attached to raise the ballast device. The abutment elements are arranged or are positionable such that the abutment means can be selectively attached to the assembly device for raising only the first ballast element above its center of gravity or for commonly raising both ballast elements above their total center of gravity. The disclosure further relates to a mobile crane having at least one such ballast device.

The disclosure relates to a ballast device for fastening to a crane having first and second ballast elements. The first ballast element has first connection means for a releasable fastening to the crane, while both ballast elements are releasably connected to one another via second connection means. According to the disclosure, the first ballast element comprises an assembly device having abutment elements to which an abutment means can be attached to raise the ballast device. The abutment elements are arranged or are positionable such that the abutment means can be selectively attached to the assembly device for raising only the first ballast element above its center of gravity or for commonly raising both ballast elements above their total center of gravity. The disclosure further relates to a mobile crane having at least one such ballast device.

The focus of the present disclosure is on portable cranes and cantilevered base systems. In particular, portable cranes and cantilevered base systems which are lightweight, easy-to-operate, safe, inexpensive, and have extended reaches with high-load capacities would be advantageous for a variety of applications. A cantilevered support to a pivotable arm that is provided by the present disclosure provides advantages when compared to other portable cranes, such as the ability to: 1) extend an arm and reach of a crane, 2) increase a load that can be lifted or lowered, 3) operate a portable crane and cantilevered base system freestanding without attaching a base to a floor, surface, or bed of a vehicle, and 4) augment the structural capacity of a portable crane and cantilevered base with mechanical devices to support a variety of applications.

A system for retaining a counterweight tray adapted for connection to a lifting machine includes a retainer adapted for connecting the counterweight tray to the lifting machine in one orientation and releasing the counterweight tray from being connected to the lifting machine in another orientation. The counterweight tray may include an opening, and the retainer may be adapted for passing through the opening in the counterweight tray in one orientation and retained thereto in another orientation. Related methods are also disclosed.

A system for retaining a counterweight tray adapted for connection to a lifting machine includes a retainer adapted for connecting the counterweight tray to the lifting machine in one orientation and releasing the counterweight tray from being connected to the lifting machine in another orientation. The counterweight tray may include an opening, and the retainer may be adapted for passing through the opening in the counterweight tray in one orientation and retained thereto in another orientation. Related methods are also disclosed.

A vehicle crane comprising a jib that is raised and lowered by at least one main tensile connector, and a counter jib, where the main tensile connector extends between a first connecting point in the region of a jib head and a second connecting point in the region of a counter jib head. To reduce loading on the jib, in particular during raising and lowering and increase its bearing load overall, the jib has a third connecting point between the first connecting point and its foot opposite the head, and a secondary tensile connector extends between the third connecting point and a fourth connecting point in the region of the head of the counter jib, or the secondary tensile connector extends between the third connecting point via a seventh connecting point on the main tensile connector and a fourth connecting point in the region of the main jib foot.

A construction machine improves ease of assembly of travelling body weights installed in a truck frame and allows a worker to easily move between one pair of side frames through the travelling body weights. The construction machine includes a lower travelling body of a crane includes a truck frame, a left side frame and a right side frame, and a front weight and a rear weight. The front weight and the rear weight each include a lower weight and an upper weight. An upper surface part of the upper weight extends continuously along a left and right direction, and a moving passage is formed between the one pair of side frames.

A construction machine improves ease of assembly of travelling body weights installed in a truck frame and allows a worker to easily move between one pair of side frames through the travelling body weights. The construction machine includes a lower travelling body of a crane includes a truck frame, a left side frame and a right side frame, and a front weight and a rear weight. The front weight and the rear weight each include a lower weight and an upper weight. An upper surface part of the upper weight extends continuously along a left and right direction, and a moving passage is formed between the one pair of side frames.

A construction machine allows a worker to easily move between one pair of side frames through a travelling body weight. The construction machine includes a lower travelling body of a crane includes a truck frame, a left side frame and a right side frame, a front weight and a rear weight, and scaffolding members. Scaffolding upper surface parts of the scaffolding members and upper surface parts of the front weight and the rear weight are disposed in line with each other along a left and right direction, and form a moving passage that allows the worker to move between the left and right side frames.

A construction machine allows a worker to easily move between one pair of side frames through a travelling body weight. The construction machine includes a lower travelling body of a crane includes a truck frame, a left side frame and a right side frame, a front weight and a rear weight, and scaffolding members. Scaffolding upper surface parts of the scaffolding members and upper surface parts of the front weight and the rear weight are disposed in line with each other along a left and right direction, and form a moving passage that allows the worker to move between the left and right side frames.