Allied Power Products, Inc. (APPI), Beaverton, Ore., recently announced the addition of an optional upper limit switch assembly for use with the company’s manual trolleys, making it possible to use their Columbia hoists in overhead hoisting applications. The limit switches are designed to prevent the hook from traveling up into the drum of the hoist even if an operator does not release the In command. When the actuator plate activates the limit switch assembly, power to the hoist is cut off and only an Out command will be accepted. Offered with a variety of wheel configurations, the trolleys are suitable for both straight and curved I-beams with bend radii as small as 4 feet.
Manual, chain, and powered positioning systems are available. Drawings are available for units with and without limit switches. Additional trolley options include stainless steel and spark resistant components for virtually any type of sensitive environment. The trolleys can also be provided in an ultra-low profile arrangement for dual I-beam applications.