A small wheel or sheave that redirects the door operator drive belt or cable in the door drive system.
Full Definition
The elevator door pulley is a grooved or flat-rimmed wheel mounted at the end of the door operator drive system to redirect the timing belt or drive cable, maintaining correct tension and alignment. Pulleys are typically nylon, glass-filled polymer, or aluminium, selected for low inertia and quiet operation. Bearing quality is critical; worn bearings cause belt skip, noise, and premature belt wear. The idler or tension pulley adjusts belt tension during installation and maintenance. In some operators, eccentric pulleys allow micro-adjustment of belt path. Replacement intervals are defined by the operator manufacturer and typically coincide with belt replacement cycles.
