{{No footnotes, date=October 2023 A sliding door operator (or sliding door opener or automatic sliding door operator) is a device that operates a

sliding door A sliding door is a type of door which opens horizontally by sliding, usually parallel to (and sometimes within) a wall. Sliding doors can be mounted either on top of a track below or be suspended from a track above. Some types slide into a ...

for pedestrian use. It opens the door automatically, waits, then closes it. Oorlogsmuseum Overloon

Uses

Sliding door operators are typically used on the outside doors of large retail businesses. (smaller retail businesses prefer

swing door operator {{unreferenced, date=June 2012 A swing-door operator (or swing-door opener or automatic swing-door operator) is a device that operates a swing door for pedestrian use. It opens or helps open the door automatically, waits, then closes it. Types ...

s.) They are also used in elevators (lifts).

Triggering

A door operator may be triggered in various ways: * Approach Sensor (such as a radar sensor) - the door opens when a user approaches it. * Pushbutton - the door opens when a user presses a button. * Access control - the door opens when an access control system determines the user is authorized to go through. * Automatically (in the case of elevators). A trigger from any of the above requests that the door be opened (or reopened if it was closing).

Safety sensors

Sensors can be used to detect obstacles in the path of closing doors. The simplest sensor consists of a light beam aimed across the opening: when the beam is broken by an obstacle, the operator prevents the door from closing.

Infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

and

radar Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...

safety sensors are also commonly used. Other sensors such as resistance-sensing motors can be used to reverse the closing action of the door after an obstacle is encountered.

Technology

The operator is placed in the space above the sliding door. An

electric motor An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a electromagnetic coil, wire winding to gene ...

, geared down to get a lower speed and a higher

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

, drives a

pulley Sheave without a rope A pulley is a wheel on an axle or shaft enabling a taut cable or belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. A pulley may have a groove or grooves between flan ...

at one end of a belt. The door is clamped to the belt. To open the door, the motor turns the pulley, which in turn turns the belt, which in turn drags the door. To close the door, the reverse occurs. Historically, elevator doors were opened using

simple harmonic motion In mechanics and physics, simple harmonic motion (sometimes abbreviated as ) is a special type of periodic motion an object experiences by means of a restoring force whose magnitude is directly proportional to the distance of the object from ...

by a set of mechanical linkages; the motor, geared down, would rotate linked arms, which in turn would drive the door.

Types

There are several types of sliding doors, these are: * Standard sliding door (single wing or double wings) * Telescopic sliding door (two wings or four wings) * Circular sliding door (segment circular, semi-circular or full circular) * Sliding folding door (two wings or four wings) * Hermetic sliding door (single wing or double wings) *

Clean room A cleanroom or clean room is an engineered space that maintains a very low concentration of airborne particulates. It is well-isolated, well-controlled from contamination, and actively cleansed. Such rooms are commonly needed for scientifi ...

sliding door (single wing or double wings)

External links

*Overview of ANSI standard
PIR Sensor based Automatic Door Opener Project
Electromechanical engineering Door automation