A forest machine has a carriage driven by a thermal engine and a towing/holding winch carried by the carriage and having a towing drum of the cable and a rotation electric motor of the towing drum commanded and controlled by an electric drive and control circuit having an accumulator pack, a detection block for detecting the electric energy absorbed by the electric motor during one or more towing steps of the load hooked to the cable and the electric energy returned in one or more holding steps of the same load, a comparator block for calculating the difference between the absorbed electric energy and the returned electric energy and an electric energy generator driven directly or indirectly by the thermal engine for sending the calculated electric energy difference to the accumulator pack; the electric drive and control circuit further having a control assembly of the tension of the cable.

A system to perform vine removal includes a winch. The winch includes a mount configured to secure the winch to a stationary object. A drum is connected to the mount and configured to rotate bi-directionally. A cable is mounted to the drum such that rotation of the drum in a first direction releases the cable from the drum and rotation of the drum in a second direction spools the cable onto the drum. A securing implement is attached to an end of the cable. The securing implement is configured to attach to one or more vines such that operation of the drum in the second direction pulls the one or move vines toward the winch.

A system to perform vine removal includes a winch. The winch includes a mount configured to secure the winch to a stationary object. A drum is connected to the mount and configured to rotate bi-directionally. A cable is mounted to the drum such that rotation of the drum in a first direction releases the cable from the drum and rotation of the drum in a second direction spools the cable onto the drum. A securing implement is attached to an end of the cable. The securing implement is configured to attach to one or more vines such that operation of the drum in the second direction pulls the one or move vines toward the winch.

Units for distributing three-phase power to a plurality of chain motors are provided, as are used to raise and suspend production elements such as lighting, sound, video, and scenery. Remote switching and phase reversal of such power are also provided. In the prior art, such switching has been performed by large, heavy contactors inserted between the single power input and its distribution to plural outputs for motors, making the unit difficult to handle and ship. Provided herein are power switching and phase reversal performed by a plurality of parallel such means, reducing the current requirements for each, and thereby the size, weight, and cost of the whole. In some embodiments, the single power input is replaced by a by a cable delivering a plurality of two-phase circuits to the unit which derives the three-phase circuits necessary for chain motors therefrom.

Units for distributing three-phase power to a plurality of chain motors are provided, as are used to raise and suspend production elements such as lighting, sound, video, and scenery. Remote switching and phase reversal of such power are also provided. In the prior art, such switching has been performed by large, heavy contactors inserted between the single power input and its distribution to plural outputs for motors, making the unit difficult to handle and ship. Provided herein are power switching and phase reversal performed by a plurality of parallel such means, reducing the current requirements for each, and thereby the size, weight, and cost of the whole. In some embodiments, the single power input is replaced by a by a cable delivering a plurality of two-phase circuits to the unit which derives the three-phase circuits necessary for chain motors therefrom.

A suspension work platform hoist system for raising and lowering a work platform is provided. The system incorporates at least one hoist attached to the work platform and in electrical communication with a hoist control system having a monitoring and diagnostic system to monitor and record at least one of a plurality of operating characteristics of the hoist. The hoist control system may further include a safety lock out system that requires authentication of an operator prior to the hoist control system causing movement of the hoist system.

A suspension work platform hoist system for raising and lowering a work platform is provided. The system incorporates at least one hoist attached to the work platform and in electrical communication with a hoist control system having a monitoring and diagnostic system to monitor and record at least one of a plurality of operating characteristics of the hoist. The hoist control system may further include a safety lock out system that requires authentication of an operator prior to the hoist control system causing movement of the hoist system.

A mobile shaft winch includes a carrier vehicle with a vehicle drive, which has an internal combustion engine, a rigid base frame and a rotary platform which is arranged on the base frame via a rotary connection. A drum winch is arranged on the rotary platform with a rope drum which is driven by a winch drive and designed for the winding on and unwinding of a haulage rope. The winch drive includes only an electric motor. A control system is designed for a selective operation of the electric motor on a mains supply system or on an electric generator. The internal combustion engine of the vehicle drive, drives the generator, and the generator and the internal combustion engine are arranged on the carrier vehicle.

A mobile shaft winch includes a carrier vehicle with a vehicle drive, which has an internal combustion engine, a rigid base frame and a rotary platform which is arranged on the base frame via a rotary connection. A drum winch is arranged on the rotary platform with a rope drum which is driven by a winch drive and designed for the winding on and unwinding of a haulage rope. The winch drive includes only an electric motor. A control system is designed for a selective operation of the electric motor on a mains supply system or on an electric generator. The internal combustion engine of the vehicle drive, drives the generator, and the generator and the internal combustion engine are arranged on the carrier vehicle.

Disclosed is a winch control apparatus for a crane, which comprises: a first compensation torque value calculation section which calculates, when a hoisting manipulation being input, based on a difference speed between a detected rotational speed and a target speed according to a manipulation amount of the hoisting manipulation, a first compensation torque value for enabling an electric motor to generate a reverse-rotation-preventing torque which is a torque in a hoisting direction and corresponding to the difference speed; and a second compensation torque value calculation section which calculates, when the hoisting manipulation being input, based on a detected load value, a second compensation torque value for enabling the electric motor to generate a load bearing torque which is a torque in the hoisting direction and necessary for bearing a load of the load value.