A lift assembly including an article to be lifted between a lowered position and a raised position, a flexible drive element coupled to the article and defining a longitudinal axis, a power mechanism coupled to the flexible drive element, a drum powered by the power mechanism and dimensioned to facilitate winding of the flexible drive element onto the drum, and a cable keeper providing a force on the flexible drive element to bias the flexible drive element toward the drum.

A lift assembly including an article to be lifted between a lowered position and a raised position, a flexible drive element coupled to the article and defining a longitudinal axis, a power mechanism coupled to the flexible drive element, a drum powered by the power mechanism and dimensioned to facilitate winding of the flexible drive element onto the drum, and a cable keeper providing a force on the flexible drive element to bias the flexible drive element toward the drum.

A portable winch and method of use is shown. One advantage of winches shown includes an ability to lower a boom or boom sections into limited access exit pit for winching operations such as pipe bursting. Sectional boom designs shown provide the ability to easily raise and lower a boom large distances without the need for a single long boom. Selected winch designs shown include flexible inserts between the boom and the winch frame that help resist damage from unforeseen shifting of the device during operation. Designs and methods shown also include multiple pulleys on a boom end unit. Fasteners are shown that reduce build up of debris.

A portable winch and method of use is shown. One advantage of winches shown includes an ability to lower a boom or boom sections into limited access exit pit for winching operations such as pipe bursting. Sectional boom designs shown provide the ability to easily raise and lower a boom large distances without the need for a single long boom. Selected winch designs shown include flexible inserts between the boom and the winch frame that help resist damage from unforeseen shifting of the device during operation. Designs and methods shown also include multiple pulleys on a boom end unit. Fasteners are shown that reduce build up of debris.

A fairlead for use with a winch is disclosed. The fairlead includes: a device for detecting a speed at which a line is being spooled or unspooled from the winch, a first and second roller adapted to aid in spooling or unspooling a line, a fairlead motor for driving at least the first roller, and a controller connected to the fairlead motor. The controller is in communication with the device for detecting the speed. The controller is configured to direct the fairlead motor to drive at least the first roller at a speed that maintains tension on the line as it is unspooling or spooling. Alternatively, the device measures current drawn by the fairlead motor and the controller directs the fairlead motor to drive the rollers at a speed that maintains a target current draw.

A fairlead for use with a winch is disclosed. The fairlead includes: a device for detecting a speed at which a line is being spooled or unspooled from the winch, a first and second roller adapted to aid in spooling or unspooling a line, a fairlead motor for driving at least the first roller, and a controller connected to the fairlead motor. The controller is in communication with the device for detecting the speed. The controller is configured to direct the fairlead motor to drive at least the first roller at a speed that maintains tension on the line as it is unspooling or spooling. Alternatively, the device measures current drawn by the fairlead motor and the controller directs the fairlead motor to drive the rollers at a speed that maintains a target current draw.

The invention relates to a method for winding a cable winch, in which method a plurality of cable winding layers is wound one over the other, a plurality of cables being wound, in multiple strands, onto the same winding region of the cable winch such that the cables are adjacent to each other in the same cable winding layer.

The invention relates to a method for winding a cable winch, in which method a plurality of cable winding layers is wound one over the other, a plurality of cables being wound, in multiple strands, onto the same winding region of the cable winch such that the cables are adjacent to each other in the same cable winding layer.

In a cable-driven three-dimensional crane system, an end-effector is moved within an operating volume defined by dynamically shifting draw points. Winch assemblies pull the end-effector toward the respective draw points. Each winch assembly includes a cable router that manages travel of its drive cable through the associated draw point. Cable length encoders determine the effective length of each drive cable, from which one method of end-effector position calculations can be made. Draw point angle trackers assess the instantaneous lateral and vertical angles of each drive cable as it vectors away from its draw point toward the carrier from which another method of end-effector position calculations can be made as well as enabling self-calibration techniques. Sensitive mechanical and electrical components are sheltered in heated enclosures that wipe debris from the drive cable and track with its changing position. Multi-zone applications allow sharing of winch assemblies.

In a cable-driven three-dimensional crane system, an end-effector is moved within an operating volume defined by dynamically shifting draw points. Winch assemblies pull the end-effector toward the respective draw points. Each winch assembly includes a cable router that manages travel of its drive cable through the associated draw point. Cable length encoders determine the effective length of each drive cable, from which one method of end-effector position calculations can be made. Draw point angle trackers assess the instantaneous lateral and vertical angles of each drive cable as it vectors away from its draw point toward the carrier from which another method of end-effector position calculations can be made as well as enabling self-calibration techniques. Sensitive mechanical and electrical components are sheltered in heated enclosures that wipe debris from the drive cable and track with its changing position. Multi-zone applications allow sharing of winch assemblies.