pure-power hoist

A hoist is a mechanical device used for lifting and lowering heavy loads, and sometimes for horizontal movement. It typically employs a block and tackle system, which involves pulleys, a rope or cable, and a hook for attaching loads. Hoists can be powered manually or by an electric motor.

In theatrical stagecraft, hoists are crucial components of flying systems, particularly in proscenium theaters. These systems lift scenery into a space above the stage called the fly loft. There are hand-operated systems, like rope-set and counterweight systems, and machine-driven systems. A "pure-power hoist" is a type of machine-driven system where electricity provides both the lifting power and the force for counterbalancing. These hoists are comprised of a motor, brake, gear reducer, and a drum for winding hoisting lines.12