The invention relates to a load-compensating rope sheave arrangement for drum winders, comprising at least two rope sheaves which are vertically guided in sliding frames and mounted on hydraulically short-circuited cylinders. Multiply redundant monitoring of the different sheave loads acting upon the rope sheaves is carried out via the hydraulic cylinders which are connected to the system control of the drum winder for communication.

Provided is a braking apparatus for braking of an electric winch of a construction machine, ensuring safe braking with much regeneration. The apparatus includes a regenerative-power generation unit, a regenerative-power receiving unit, a braking device for mechanical braking separately from the regenerative-power generation unit, and a braking control unit including a necessary-braking-capacity calculation section, a regeneration-capacity calculation section calculating a regeneration capacity, and a command section. The command section, when the regeneration capacity is not less than a necessary braking capacity, performs braking with only a regenerative action while not operating the braking device and, when the regeneration capacity is less than the necessary braking capacity, calculates an auxiliary braking force equivalent to a difference between the necessary braking capacity and the regeneration capacity and brings the braking device into braking action with the auxiliary braking force.

Provided is a braking apparatus for braking of an electric winch of a construction machine, ensuring safe braking with much regeneration. The apparatus includes a regenerative-power generation unit, a regenerative-power receiving unit, a braking device for mechanical braking separately from the regenerative-power generation unit, and a braking control unit including a necessary-braking-capacity calculation section, a regeneration-capacity calculation section calculating a regeneration capacity, and a command section. The command section, when the regeneration capacity is not less than a necessary braking capacity, performs braking with only a regenerative action while not operating the braking device and, when the regeneration capacity is less than the necessary braking capacity, calculates an auxiliary braking force equivalent to a difference between the necessary braking capacity and the regeneration capacity and brings the braking device into braking action with the auxiliary braking force.

The invention relates to a motor-operated crane drive in which a more rapidly rotating motor (1) drives a more slowly rotating cable drum (3) via a transmission (3). A safety brake (5) is arranged on the more slowly rotating side of the transmission (2). A signal that is used for actuating the safety brake (5) is utilized for initiating an electrical deceleration of the motor (1).

A system includes a first transmission having a first planetary gearset, a first drive shaft, and a first annular sleeve. The first annular sleeve is positioned circumferentially about the first drive shaft, and the first annular sleeve is configured to move axially relative to the first drive shaft and the first planetary gearset from a first axial position in which the first annular sleeve engages a first sun gear of the first planetary gearset to a second axial position in which the first annular sleeve engages a first ring gear of the first planetary gearset to adjust a gear ratio of the first transmission.

A drawworks system for a mineral extraction system includes a drum mounted on a drum shaft and configured to support a cable. The system also includes a gearbox assembly having a gearbox housing, a gearbox supported by the gearbox housing and having a gearbox input shaft and a gearbox output shaft, wherein the gearbox input shaft is configured to be coupled to at least one motor and the gearbox output shaft is coupled to the drum shaft to drive rotation of the drum shaft and the drum, and a brake supported by the gearbox housing and coupled to the drum shaft to block rotation of the drum shaft and the drum, wherein the gearbox and the brake are positioned on one side of the drum along an axial axis of the drawworks system.

The invention relates to a construction machine having a mast and a lifting element which can be moved up and down along the mast with a hoist rope. The hoist rope can be activated by means of two rope winches. At least one first rope winch is designed as a free fall winch, wherein the hoist rope can be lowered in free fall. To lower the hoist rope a controller is provided, with which the first rope winch, which is designed as a free fall winch, can be switched into a free fall mode. Meanwhile, a second rope winch is operated in force-locking manner.

The invention relates to a construction machine having a mast and a lifting element which can be moved up and down along the mast with a hoist rope. The hoist rope can be activated by means of two rope winches. At least one first rope winch is designed as a free fall winch, wherein the hoist rope can be lowered in free fall. To lower the hoist rope a controller is provided, with which the first rope winch, which is designed as a free fall winch, can be switched into a free fall mode. Meanwhile, a second rope winch is operated in force-locking manner.

In at least one illustrative embodiment, a winch may include first and second end frames, a drum coupled between the first and second end frames and configured to rotate to wind or unwind a cable, a brake configured to resist rotation of the drum when engaged, a switch configured to cause the brake to engage the drum when the switch is activated, a slack arm frame having a first end engaged with the cable and a second end pivotally coupled between the first and second end frames, where the slack arm frame is configured to pivot between a first position when the cable is taut and a second position when the cable is slack, and a cam coupled to the slack arm frame and configured to rotate with the slack arm frame to activate the switch when the slack arm frame is in the second position.

In at least one illustrative embodiment, a winch may include first and second end frames, a drum coupled between the first and second end frames and configured to rotate to wind or unwind a cable, a brake configured to resist rotation of the drum when engaged, a switch configured to cause the brake to engage the drum when the switch is activated, a slack arm frame having a first end engaged with the cable and a second end pivotally coupled between the first and second end frames, where the slack arm frame is configured to pivot between a first position when the cable is taut and a second position when the cable is slack, and a cam coupled to the slack arm frame and configured to rotate with the slack arm frame to activate the switch when the slack arm frame is in the second position.