Abstract: A load-balancing device can be used to assist the lifting and lowering of heavy objects. In some examples, a load-balancing device includes a housing, a first movable pulley, a second movable pulley, a stationary pulley positioned between the first movable pulley and the second movable pulley, and a cable wound at least partially around the first movable pulley, the second movable pulley, and the stationary pulley. In operation, a pressurized control fluid may be introduced into a pressure chamber defined between the housing, the first movable pulley, and the second movable pulley. This can cause the first movable pulley and the second movable pulley to move away from the stationary pulley, withdrawing the cable into the housing and lifting a load attached to the cable.

Abstract: A load-balancing device can be used to assist the lifting and lowering of heavy objects. In some examples, a load-balancing device includes a housing, a first movable pulley, a second movable pulley, a stationary pulley positioned between the first movable pulley and the second movable pulley, and a cable wound at least partially around the first movable pulley, the second movable pulley, and the stationary pulley. In operation, a pressurized control fluid may be introduced into a pressure chamber defined between the housing, the first movable pulley, and the second movable pulley. This can cause the first movable pulley and the second movable pulley to move away from the stationary pulley, withdrawing the cable into the housing and lifting a load attached to the cable.

Abstract: A load balancing hoist constructed to combine the power module and the travel module of the hoist into a single unit to substantially reduce the cost and the length of the hoist without effecting its operation and application.

Abstract: A load balancing hoist constructed to combine the power module and the travel module of the hoist into a single unit to substantially reduce the cost and the length of the hoist without effecting its operation and application.

Abstract: A cable retraction speed limiter has a body which is designed to be mounted on the housing of a hoist and a spool which is rotatably supported by the body. A flexible extension member is disposed about the spool so that it can be extended from and retracted onto the spool by rotation of the spool. The end of the flexible extension member is designed to be attached to an air pressure responsive member inside of the air balancing hoist. The cable retraction speed limiter also includes a spool lock that stops rotation of the spool when the rotational speed of the spool exceeds the rotational speed limit, thereby limiting the hoist cable retraction speed.

Abstract: A fluid control valve fluidly connected between a source of fluid pressure and a fluid operated device for controlling the pressurization and depressurization of the fluid device. The control valve comprises an elongated housing having an inlet port and an outlet port formed at one axial end of the housing and an exhaust port formed at its other end. The inlet port is connected to the fluid pressure source while the outlet port is connected to the fluid device. A first fluid passageway formed in the housing fluidly connects the inlet port to the outlet port while, similarly, a second fluid passage in the housing fluidly connects the outlet port to the exhaust port. A first valve is disposed in the first fluid passageway and movable between an open and closed position while a second valve is disposed in the second fluid passageway and also movable between an open and closed position.