Automatic door systems are installed and used for the more welfare and as well as the protection and security purposes in different places on different types of doors such as garage doors, patio door, entrance door of the building and even the rooms door of the building (for disabled people). After installing these systems, the door can be opened and closed only by pressing the button on a remote control from  the appropriate distance and or can be opened and closed the door automatically by installing  special sensors when traffick.

Various types of automatic doors that these systems can be installed on it, are as follows:

Automatic sliding doors (rail): These automatic doors are a piece and slip on the rail at the bottom of the door and move left and right.

Automatic Swing Door: Automatic doors that are double leaves or single leaf and have horizenal movement around a higane.

Sectional Automatic doors: The automatic doors are placed on each other as horizontal pieces and move up when opening and then rotated 90 degrees to be placed parallel to the ceiling.

Tilt doors: The automatic doors  swing  with vertical movement on two points on either side seamingly and place parallel to the ceiling.

Automatic Roller doors: the automatic doors gather on top with swinging around an axis (Like shutters of shops).

The systems with different mechanisms  are designed to open and close different types of automatic doors But most systems are electromechanical type. The main parts of an automatic door opener system with electromechanical mechanism is as follows:

1. The electric motor
2. Mechanical parts or gearbox
3. The electronic board
4. Safety Equipment
5. Manual control buttons
6. Remote Control

Now, we discusse above parts:

1. The electric motor

In most cases, single phase motors are used for automatic opener door system.

The engines must have the ability of be dextrorotation and levorotation. So single phase motors with the two similar coils are used which can be changed direction of engine movement  with the series settling of a capacitor with each coils direction.

Usually four wires exits from the engine which a wire as earth and two other wires connect to two–terminal  of capacitor and is a common wire. All motor wires are connected electronic circuit terminals at the end. These engines with powers 50 watts to 1000 watts are used for different doors in size and weight. Only about  two leaves automatic doors are used two engines but in other cases, just one engine is used.

The point that should be noted about engines work is that the indiscriminate and persistent work of engine in these systems cause engine overheating and damage the engine then  should be avoided to open and close the door continuously and without break.

2. mechanical parts or gearbox

Due to the lack of  the power of one conventional single phase motors to open and close the doors,  Its power should be increased by a mechanical system. Usually, the gearbox is used for the work. After increasing the force ,how to transfer it to the door depends on  the type of door and is done in various ways. For rail  automatic doors (sliding), power will be transmitted by a gear of a mechanical drive shaft to shoulder drive  gear  mounted under the door.

In the case of tilt automatic doors opened and closed vertically and the power is transmitted by chain or belt  in tilt door and for a single leaf or double leaves doors, the door  are opened and closed by arms. Gearbox System, In some models made for double leaves  or single leaf automatic doors,consists of spiral screw and a nut attached to it which the door openes and closes by turning the screw and nut movement. We must rid the gearbox shaft for being able to open and close the door when nesecary (for adjustment during installation or in case of power failure).

The work is done by Allen wrench where the gearbox is located and then rotated  in the corresponding location on the engine ,in brachial opener systems It’s done, in systems for roller automatic doors, by wire rope and in the tilt doors or sectional doors which the main device is installed on the roof, by hanging string. In systems that have been developed for sliding doors, this work is done by opening a small door on the main device by a switch.

3. The electronic board

This board is used to control and adjust the door movement time and its location varies on different systems. For example, the board is installed  in sliding door systems on main device and in swing door systems in  a panel beside the door separately.

4. Safety Equipment

Because of  preventing of damage to people and vehicles when moving of automatic doors, it must be used of equipments which announce the door movement and either, stops or opens the door probably in the case of passing person or vehicle when the door moves.

Usually, for this purpose, it’s used the following equipment:

Infrared sensors:

These sensors are commonly called photoelectric sensor, has two separate parts of transmitter (TX) and receiver (RX). A pair of these sensors is  installed (receiver and transmitter) on the outside and another pair at indoors on the both sides in front of each other. The minimum  of  mounting height is 25 cm and install them in places on a particular base ,where mounting on wall is not possible. The operation of sensors is that the transmitter (TX) generates and broadcasts infrared light by a diode of gallium arsenide.

This radiation  is received by a photodiode on the receiver (RX). Usually there is one LED diode on receiver when radiation is received, it is turned off. In case a of passing a person or vehicle between the two pieces and cutting the transmitted radiation, LED on the receiver is turned on and one relay on the receiver  stimulates. Relay contacts connect to the control circuit on the electronic board and in this way, the board can give essential instruction to the engine  for stopping the door ( if it’s closing) or opening door according to performed settings  on  the board.

5. manual control buttons

These buttons include a button to open and  a button to close (STOP) which are used to door movement for opening and closing or stopping it if there is not remote control. Of course the STOP button must be installed in a suitable place available to be used in an emergency times to stop doors. close button  of  STOP is installed inside and the open button of the START is usually as switching form And can be opened with a key such as key of conventional doors. (To inserting switch to the correct place and rotating it, its open contact to be closed) and is installed on the outside.

6. Remote Control

A small hand-held radio transmitter, which is called remote control, is used to control  automatic door opener system remotely. There are push button on the remote which are used to open or close or stop the automatic doors.

Remote control with antenna and radio receiver cards on the electronic board constitute the radio communication components  of the device.