Abstract:
A hoist system with an overspeed detection sub-system for detecting overspeed by comparing an actual drum assembly speed with a target value. For example, the rotation of a motor may be determined by a first rotary encoder and the rotation of a drum may be determined by a second rotary encoder. The output of the first rotary encoder (the basis of a target value) is compared with the output of the second rotary encoder (corresponding to actual motion of the drum). If the difference between the target value and the actual motion is too large, then a problem, such as a broken hoist hardware component may exist, and appropriate remedial action is taken, such as braking the motor and/or the drum.
Abstract:
A winch system with a force cable that transmits electrical current and/or digital data to the load. For example, the force cable, including a power line and/or a signal line and includes at least: (i) a first portion extending from the load to the drum; and (ii) a second portion that is wound around the drum. If there is a power line in the force cable it is electrically connected to an electrical commutator by a rotating current path. If there is a signal line in the force cable it is connected in data communication to a data signal commutator by a rotating communication path. The commutator also has an input for receiving electrical current and/or digital data, as appropriate. The commutator transmits the electrical current and/or digital data from its input to the rotating current path and/or communication path. The drum defines an axial channel extending from at least one end of the drum along its axial direction, and current path(s) and/or communication path(s) are routed through the channel. There is a distribution box at a first axial end of the drum and the commutator is at the second axial end of the drum. The drum includes at least one radial channel that includes: (i) a first portion for receiving a force bearing member of the force cable from outside of the drum; and (ii) a second portion for guiding at least a portion of the current path(s) and/or the communication path(s) from outside of the drum to the axial channel.
Abstract:
A cable-wound drum style hoist with a rotating shaft supported by bearings that has both: (i) some freedom of motion in (at least) one of the bearings; and (ii) a pillow block in the shaft to impart some freedom of motion (beyond freedom to rotate about the central axis) in the shaft itself. By allowing some freedom of motion both the bearing(s) and the shaft, the hoist can better accommodate for bent shafts and/or slight misalignment of coaxial bearings. Also, a set of preferred connection hardware for mechanically connecting a hoist reducer box to a hoist backbone with preferred degrees of freedom/constraint.
Abstract:
A twisted rope for use in rigging systems that includes a differently colored yarn positioned within at least one strand. As the rope is worn, the differently colored yarn will become exposed, thereby serving as a visual indicator of wear to the rope. A plastic strip printed with identifying information about the rope is placed within the fibers of the rope during manufacture may also be positioned with a strand of the twisted rope. A user can simply unravel one end of the rope and read the information printed on the strip to determine, for example, the composition of the rope, when the rope was manufactured, the load-bearing characteristics of the rope, and who was the rope manufacturer.
Abstract:
A twisted rope for use in rigging systems that includes a differently colored yarn positioned within at least one strand. As the rope is worn, the differently colored yarn will become exposed, thereby serving as a visual indicator of wear to the rope. A plastic strip printed with identifying information about the rope is placed within the fibers of the rope during manufacture may also be positioned with a strand of the twisted rope. A user can simply unravel one end of the rope and read the information printed on the strip to determine, for example, the composition of the rope, when the rope was manufactured, the load-bearing characteristics of the rope, and who was the rope manufacturer.
Abstract:
The present invention discloses a drive system for theatrical rigging, comprising a drive rope and a drive pulley. The drive rope has a fiber or cable core, surrounded by a plastic jacket. Formed on or in the surface of the drive rope are traction features that engage corresponding grooves in the drive pulley.
Abstract:
The invention is a compact drive for a counterweight-assisted winch which can be retrofitted into existing manually operated systems that use counterbalancing weights. The counterbalancing weight will be fixed at a first predetermined percentage of the maximum capacity of the set, preferably about 50%. The winch is rated at a second predetermined percentage of the maximum capacity of the set, preferably about 50%. Together the first and second predetermined percentages sum to at least 100% of the maximum capacity of the set. By using the winch in a closed loop configuration, it will operate the set at any load from 0 to 100% of the set's rated capacity, without the need to adjust the counterbalancing weights. The compact drive system employs two motorized winches positioned along the long axis of two adjacent counterweight rigging systems, each winch engaging a respective chain used to move a counterbalancing weight.
Abstract:
The invention is a compact drive for a counterweight-assisted winch which can be retrofitted into existing manually operated systems that use counterbalancing weights. The counterbalancing weight will be fixed at a first predetermined percentage of the maximum capacity of the set, preferably about 50%. The winch is rated at a second predetermined percentage of the maximum capacity of the set, preferably about 50%. Together the first and second predetermined percentages sum to at least 100% of the maximum capacity of the set. By using the winch in a closed loop configuration, it will operate the set at any load from 0 to 100% of the set's rated capacity, without the need to adjust the counterbalancing weights. The compact drive system employs two motorized winches positioned along the long axis of two adjacent counterweight rigging systems, each winch engaging a respective chain used to move a counterbalancing weight.
Abstract:
A failsafe brake is provided for preventing the uncontrolled descent of a counterweight arbor or stage equipment load in a counterweight rigging systems. Specifically provided is a failsafe brake according to which a brake shoe is biased to contact a counterweight arbor guide rail and grip it between the brake shoe and a backer plate, except when tension is applied to a line to move the counterweight arbor.
Abstract:
A lift system having a modular backbone with two or more backbone sections being attached end to end to form the backbone. Also, a lift system with end to end modular attachment, using universal joints, between motor assembly(ies), shaft section(s), drum assembly(ies) and/or shaft end sections. Also, a lift assembly with a backbone having longitudinally adjustable lift component attachment hardware, such as an elongated slot with lips suitable for engaging a nut tooth.