1. Product Definition of Automatic Doors
An automatic door is a system that can recognize the action of a person approaching the door (or a certain entry authorization) as an opening signal through a control unit. Then, it drives the door to open and automatically closes it after the person leaves. At the same time, it can control the opening and closing process.
2. Classification of Automatic Doors
By Opening Method
- Sliding Door : This is a common type of automatic door. It slides along a parallel track. Can be further divided into single-slide, double-slide, overlapping single-slide, overlapping double-slide, and arc-shaped sliding door. The arc-shaped sliding door moves smoothly along an arc-shaped track, including semi-arc one-way, semi-arc two-way, and full-arc two-way. Some sliding (nested) automatic doors can be made with a manual one-way opening at the end of the opening and fixed fan coincidence, which is also classified as a sliding door.
- Swing Door : Suitable for corridors and indoor doorways, providing 100% passage width. Can be divided into single-door one-way, double-door one-way, single-door two-way, and double-door two-way.
- Folding Door : Consists of multiple door panels that can be folded. Can be classified into multi-panel single-open type and multi-panel double-open type. According to the folding point, it can be divided into door panel end folding and door panel center folding.
- Revolving Door: Usually installed in places with a large flow of people, such as airports, stations, and hotel lobbies. Can be further classified by the number of door panels, such as two-wing, three-wing, and four-wing. Also classified by the display stand, such as with a display stand or without a display stand.
- Arc-shaped Door : Can be divided into arc sections, semi-circles, and full circles. It can have a fixed door panel or no fixed door panel, and the arc degree can be set according to specific cases. It is very flexible in application and can also be spliced with different arc degrees to construct a door body with a beautiful and changeable geometric shape.
- Emergency Evacuation Automatic Door : Both the movable fan and the fixed fan can be opened 90 degrees.
- Overlapping Door : Can be divided into an overlapping automatic door with a fixed edge door panel and an overlapping automatic door without a fixed edge door panel.
By Door Body Material
- Safety glass automatic door
- Stainless steel decorative surface automatic door
- Architectural aluminum alloy profile automatic door
- Color-coated steel plate automatic door
- Wood automatic door, etc.
By Use Method
- Civil Automatic Door : Used in residential settings.
- Commercial Automatic Door : Commonly seen in commercial buildings, shopping malls, etc.
- Medical Automatic Door : Designed to meet the specific needs of medical facilities.
- Emergency Exit Door : Primarily used for emergency evacuation purposes.
Other Types
- Garage Automatic Door : Classified by vehicle size, such as villa garage automatic door (for household) and large garage automatic door. Also classified by movement type, including smooth type, swing type, folding type, lifting type, flap type, and rolling shutter type.
- Courtyard Automatic Door : Classified by door body movement type, such as smooth type, swing type, and telescopic type. Also classified by the presence or absence of a guide rail, number of guide rails, number of door panels, and door body material.
- Automatic Barrier Gate : Classified by the number of barrier poles, such as single-pole single-open type and double-pole opposite-open type. Also classified by the control method, such as ordinary electronic control type and automatic control type.
It should be noted that the classification of automatic doors may vary depending on different standards and practical applications. When choosing an automatic door, factors such as the specific use environment, functional requirements, safety considerations, and aesthetic preferences should be taken into account.
3. Working Principles of Automatic Doorsof Automatic Doors
3.1 Door Opening Signals
- Microwave Radar: It reacts to the displacement of objects and has a fast response speed. It is suitable for places where people with normal walking speeds pass through. When a person near the door stops moving and does not want to go out, the radar no longer reacts, and the automatic door closes, which has a certain protective effect on the door operator.
- Infrared Sensors: They react to the existence of objects. As long as a person is within the scanning range of the sensor, it will react and send out a contact signal. However, the reaction speed is relatively slow and is suitable for places where people with slow movements enter and exit. If the automatic door receives a contact signal for too long, the controller may think that there is a problem with the signal input system. And if the automatic sliding door remains open for too long, it will also damage the electrical components.
- Key Switches: Key switches can be a contact button, and the elbow touch switch is more convenient. It is durable and can be operated with the elbow to avoid hand contact. There are also foot switches, but they have higher requirements for waterproofing and are prone to failure due to large stepping force. There is also a handle with a contact switch. When the handle is pushed (or pulled in the opposite direction) in place, it provides a contact signal to the door operator.
- Timer: The timer can automatically control the state of the door by connecting the clock to a specific switch circuit. It can preset the time to automatically open or lock the door.
3.2 Access Control System and Automatic Doors in Non-Public Areas
The access control system is used to identify entry authorization. After the identification or detection of entry authorization is passed, it provides an opening signal to the automatic door control system. Before providing the opening signal, the automatic door must be in a locked state. The access control system includes simple key switches, combination locks, magnetic card locks, and complex weight recognition systems, fingerprint recognition systems, etc. In the end, they all provide a contact signal for the automatic door to open. The shielding of the signal circuit is very important to avoid the occurrence of accidental door opening due to interference from irrelevant signals.
3.3 Coordination between Unlocking and Opening Actions
For automatic sliding doors, there are electromagnetic locks that lock the belt, electric locks that lock the door hanger, and locks for the motor. For automatic hinged doors, there are electromagnetic door holders, electronic bolt locks, and electronic door openers. The direction of the opening force of the electronic door opener does not affect the opening action of the door and is not prone to misoperation. There is also a mechanical lock with a contact switch, which combines the lock and the switch. When the lock is not in the unlocked state, the contact cannot be made, and misoperation cannot occur.
3.4 Centralized Control
Centralized control includes centralized monitoring of the running status of automatic doors and centralized operation of multiple automatic doors. Centralized monitoring of the opening and closing status of automatic doors can be achieved through a position signal output circuit. It can use a contact switch or an inductive signal generating device. When the door reaches a certain position, it triggers the switch or the sensor to send a signal. In the central control room, corresponding indicator lights can be set to display the status of the automatic door. Centralized operation usually means opening or locking multiple doors at the same time, which depends on whether there are corresponding terminals on the automatic door controller. The emergence of centralized control provides a technical guarantee for the realization of intelligent building systems.
4. Problems Encountered in Automatic Doors and Solutions
4.1 Theft Prevention Problems of Automatic Doors
Most automatic doors on the market are not locked. Some external personnel may directly push the door open when they do not have a card and cannot get permission from internal personnel, which brings security risks. Moreover, the automatic door operator may be burned out if it is repeatedly forced open.
4.2 Solutions
- Installing Electric Locks: Install an electric lock, such as the DL016 anode lock of Beijing Huashijia Company. It has the advantages of hidden installation, high security, and beauty. This lock has functions such as automatic unlocking when the power is off, automatic retraction of the lock tongue when the door is not closed and reopened to avoid glass breakage, and a lower working current and temperature when the door is locked to extend the service life of the lock. However, when the power is off, there is a security risk that anyone can pass through. To solve this problem, a battery can be equipped to ensure that the system can work normally for several hours after a power outage.
- Solving the Coordination Problem between Doors, Locks, and Access Control: Remove the entry radar probe and use the access control to control the opening of the automatic door. Use the probe to control the lock switch when going out and set a 3-second delay for the door opening to ensure that the lock is opened first and then the door is opened to avoid jamming.
5. Conclusion
Automatic doors play an important role in modern life. Understanding their classification, working principles, and solutions to problems can help us better use and manage automatic doors, improve the safety and convenience of buildings, and promote the development of intelligent building technology. With the continuous progress of technology, automatic doors will continue to be improved and innovated to meet the growing needs of people.
