Why can automatic doors open and close automatically?
In front of many high-end commercial buildings or halls, there are doors that can open and close automatically. When a person walks towards it, the door will automatically open, and when a person enters, it will automatically close. It's amazing, how does it know that someone is going in? What kind of force opened the door? In fact, the earliest automatic doors existed 3000 years ago, but they are much more complicated than the current ones.
With the development of science today, there are more and more types of automatic doors, and their structures are becoming simpler. They feel the arrival and departure of people in different ways, and in the end they all open or close the door through electric power.
Do you know what are the more common automatic doors?
There are three main ways to operate modern automatic doors:
There is a pressure switch under the pedal.
This kind of door is to put a carpet in front of the door, and there is a wire under the carpet to connect to the power source. When a person stands on the carpet, the weight of the carpet increases, so the power is turned on and the door is opened; after the person enters, the weight on the carpet is reduced, and the power is turned off. After a few seconds, the door closes automatically.
②Photoelectric beam type:
Set up a beam emitting device and a photoelectric sensor device near the door
This kind of door has a light beam near the door. When people pass by, the light beam is interrupted, so the power is turned on and the door is opened; after people enter, the light beam continues to recover and the power is cut off. After a few seconds, the door Then it closes automatically.
Press a button similar to a switch to open the door leaf.
This kind of door has a switch beside the door. When people put their hands on the switch and press the switch, the power is turned on and the door is opened; after a person enters, the power is turned off after a few seconds, and the door is automatically closed.