Abstract: An improved chain motor drive controller is provided for a chain hoist. The system employs a position encoder including a position sensor located within the casing of the chain hoist to producing encoded electrical position signals. A motor pulley is mounted on the chain motor rotary drive shaft and is coupled by a cogged belt to rotate an encoder pulley that is mounted on the same shaft as the position sensor. A mechanical coupling is thereby provided entirely within the casing of the chain hoist to transmit rotary motion from the rotary drive shaft directly to the position sensor. Also, tracking circuitry, likewise located entirely within the chain hoist casing, receives electrically encoded destination signals and compares these to signals from the position sensor.

Abstract: An improved chain motor drive controller is provided for a chain hoist. The system employs a position encoder including a position sensor located within the casing of the chain hoist to producing encoded electrical position signals. A motor pulley is mounted on the chain motor rotary drive shaft and is coupled by a cogged belt to rotate an encoder pulley that is mounted on the same shaft as the position sensor. A mechanical coupling is thereby provided entirely within the casing of the chain hoist to transmit rotary motion from the rotary drive shaft directly to the position sensor. Also, tracking circuitry, likewise located entirely within the chain hoist casing, receives electrically encoded destination signals and compares these to signals from the position sensor.

Abstract: A portable three-phase alternating current power supply is provided to drive one or more chain hoist drive motors. The portable power supply has a portable case for holding electrical components and includes a control panel that has at least one single-phase power input socket, and preferably a pair of three-phase motor power output sockets and a pair of motor control output sockets. Three-phase inverters are located in the portable case and are coupled to receive one or more single-phase 110 V alternating current power inputs and to provide three-phase, 208 V alternating current electrical power outputs through the three-phase motor power output sockets. Selector switches on the control panel are used to drive the chain hoist motors to raise and lower loads. Phase selection switches on the control panel synchronize the outputs of the inverters with the selector switch positions and associated indicators.

Abstract: A portable three-phase alternating current power supply is provided to drive one or more chain hoist drive motors. The portable power supply has a portable case for holding electrical components and includes a control panel that has at least one single-phase power input socket, and preferably a pair of three-phase motor power output sockets and a pair of motor control output sockets. Three-phase inverters are located in the portable case and are coupled to receive one or more single-phase 110 V alternating current power inputs and to provide three-phase, 208 V alternating current electrical power outputs through the three-phase motor power output sockets. Selector switches on the control panel are used to drive the chain hoist motors to raise and lower loads. Phase selection switches on the control panel synchronize the outputs of the inverters with the selector switch positions and associated indicators.