The complete drive unit comprising motor, brake, and sheave that raises and lowers the elevator car via hoisting ropes or belts.
Full Definition
The elevator hoisting machine is the prime mover of a traction elevator, consisting of a traction motor (AC induction or permanent magnet synchronous), electromagnetic disc or drum brake, drive sheave, and supporting frame. Geared machines (worm or helical gear) couple the motor to a slower-turning sheave and are used for speeds up to approximately 1.6 m/s. Gearless machines directly mount the sheave on the motor shaft and dominate high-speed (>1.6 m/s) and MRL applications due to higher efficiency. Machine efficiency is measured under EN ISO 25745. The electromagnetic brake is safety-critical: EN 81-20 requires two independent brake circuits capable of stopping and holding the car at rated load. Machine room-less (MRL) machines are compact and fit within the hoistway, eliminating a separate machine room.
