How the Doors of Commercial and Residential Elevators Work
How Elevator Doors Work
How Passenger Elevators’ Doors Work
The sliding doors on residential and commercial lifts work differently than most people picture. The first thing to understand when learning how the doors on both commercial and residential elevators work is that there are actually two separate sets of doors: the doors of the elevator car itself and the landing doors found on each floor. These sets of doors work together to keep the passengers inside commercial elevators safe.
Commercial Elevators’ Car Doors
The car doors of passenger elevators use an electric motor that receives signals from the car’s computer when it needs to operate. When commercial or residential lifts reach their floor, the onboard computer sends a signal to the motor that in turn spins a wheel and pulls apart two metal arms, one connected to each door. The doors then slide smoothly along metal rails. They must close again before the elevator can resume operating. Most modern elevators also use a motion detector in order to prevent the doors from closing when someone is moving between them.
At each landing, there is a set of landing doors. The landing doors are actually opened by a mechanism on the car doors. When the elevator car reaches a landing, the mechanism on the car doors links up with the landing doors, unlocking them and pulling them apart along with the car doors. The design of the landing door mechanism is largely a safety feature: Allowing the landing doors to only open once the car has reached its floor prevents passengers from accidentally falling into the open shaft.