The toothed metal plate fixed at the upper and lower landings of an escalator whose teeth intermesh with the cleats of the moving steps, providing a safe transition between the stationary landing and the moving step surface.
Full Definition
The comb plate is one of the most safety-critical components in an escalator installation. Its toothed fingers intermesh precisely with the cleated profile of each passing step, ensuring that any small object (a shoelace, a toe, a coin) lying on the step tread is deflected upward by the comb teeth rather than being dragged into the gap between the step and the landing. EN 115-1 specifies strict dimensional tolerances for comb plate tooth geometry, the maximum gap between comb teeth and step cleat sides (≤4 mm horizontally, ≤6 mm vertically), and the minimum comb engagement depth. The comb plate must be securely fixed and must incorporate a step-level detector: if a step or pallet rises above its normal height (due to a damaged step chain or foreign object), the comb plate deflects or a safety switch beneath it trips, stopping the escalator before the raised step impacts the comb teeth and causes entrapment or structural damage. EN 115-1 requires the escalator to stop within a defined deceleration distance when a comb impact is detected. Regular inspection of comb teeth for missing, bent, or worn teeth is a critical maintenance task.
