A pulley block may include an alpha pulley block including an alpha connector, a beta pulley block including a beta connector, wherein the alpha pulley block is coupled to the beta pulley block when the alpha connector is coupled to the beta connector. At least one of the alpha connector and the beta connector may comprise magnets.

A device for moving an object is disclosed. The device has a drive cylinder with drive grooves and a set of idler pulleys. The idler pulleys are on a shaft that is parallel to the drive cylinder. Each of the idler pulleys rotate at an angle around the drive shaft that aligns the grooves of the idler pulleys to neighboring drive grooves. This allows the line to pass onto the drive groove, around an idler pulley, and onto a next adjacent drive groove. The line therefore winds back and forth between the drive grooves, the idler pulleys, and back to the next drive groove. One end of the line is placed under tension and the other is attached to an object or to a fixed member. The drive cylinder is driven and the line is moved through the device, or the device is moved along the line, respectively.

A unitary fastener and cable guidance device is operable with a pulley block assembly for stringing cable across towers. The device guides a cable onto a sheave wheel of the assembly, while fastening directly to the assembly through a unitary cantilevered axle. The one-piece design comprises a pair of discs forming an annular depression there between, and a cantilevered axle extending from the outer side of one disc. This unitary configuration reduces the number of fasteners and other components. Since the cantilevered axle is the fastening mechanism, rather than a separate fastener passing through a hole through the center of the device, the minimum outer diameter of the annular depression can be smaller than the outer diameter of the cantilevered axle, allowing the central portion of the device to be smaller and thus its sides to be higher, which helps hold the cable more robustly within the device.

A modular elevator sheave comprises a mandrel body, wherein multiple sheave units are arranged side by side along the mandrel body, and wherein, the outer wall of the outer circumference of the sheave unit is provided with a groove. In this structural composition, the mandrel body with multiple sheave units, which increases the overall strength and rigidity of the sheave. Furthermore, the number of sheave unit used can be increase and decrease depending on the need or situation, and it should be noted that since the sheave unit can be replaced individually when damaged, it is easier to maintain and reduce repairing costs.

Described herein is a hoisting block for a crane. The hoisting block includes an engaging element such as a load hook, to which a lifting tool such as a sling or a hoisting frame can be coupled. The hoisting block is provided with winches, outgoing winch cables of which are configured to carry the lifting tool to the engaging element and couple it to the engaging element. Also described herein is a crane provided with the hoisting block. The hoisting block can be applied for carrying a lifting tool to an engaging element and coupling it to the load-bearing means, or for stabilizing an engaging element relative to a support structure.

A pulley includes a securing head and a first flange. A first shaft extends from the first flange. A sheave is mounted rotatable around the first shaft in one direction of rotation only. A cam is mounted able to move away from or towards the sheave. A spring is fitted to exert a force moving the cam towards the sheave. A handle is mounted on the first flange to move the cam between the first and second positions.

The present invention relates to a lifting device for a crane which comprises a lifting cable winch, a lifting cable and a load-receiving means (10), the load-receiving means (10) being connected to the lifting cable and being movable by means of the lifting cable winch, in particular vertically movable. According to the invention the lifting device has at least one spring mounting (12) so that on the whole the load to be lifted and received by the load-receiving means (10) is mounted in a sprung manner.

The present invention relates to a lifting device for a crane which comprises a lifting cable winch, a lifting cable and a load-receiving means (10), the load-receiving means (10) being connected to the lifting cable and being movable by means of the lifting cable winch, in particular vertically movable. According to the invention the lifting device has at least one spring mounting (12) so that on the whole the load to be lifted and received by the load-receiving means (10) is mounted in a sprung manner.

A dump block assembly for a dragline bucket rigging assembly including a frame assembly having a first side frame and a second side frame attached to and parallel to the first side frame. The first side frame includes a first attachment portion having a first upper connection portion, a first lower connection portion opposite the first upper connection portion, and a first central connection portion spaced apart from and in between the first upper connection portion and the first lower connection portion. The second side frame includes a second attachment portion having a second upper connection portion, a second lower connection portion opposite the second upper connection portion, and a second central connection portion spaced apart from and in between the second upper connection portion and the second lower connection portion.

A dump block assembly for a dragline bucket rigging assembly including a frame assembly having a first side frame and a second side frame attached to and parallel to the first side frame. The first side frame includes a first attachment portion having a first upper connection portion, a first lower connection portion opposite the first upper connection portion, and a first central connection portion spaced apart from and in between the first upper connection portion and the first lower connection portion. The second side frame includes a second attachment portion having a second upper connection portion, a second lower connection portion opposite the second upper connection portion, and a second central connection portion spaced apart from and in between the second upper connection portion and the second lower connection portion.