1: The elevator is a linear load-carrying tool for high-rise buildings. Except for the car, there is nothing in the shaft that can block the falling of objects. It can also be said that the elevator shaft is a high-risk area, so the elevator door is divided into double-layer door of inner door and outer door.
2: The inner door of the elevator has the function of opening and closing the outer door.The inner door relies on the elevator door machine motor to open and close the car door.The inner door is equipped with guide wheels and supporting wheels, which are very light loads.
3: The outer door of the elevator is also the floor door. The door of this floor entering and leaving the elevator is not equipped with a door opening device. The elevator door is driven by the car door (inner door). When the car is not stopped on the floor, the outer door can be opened only by the door opening tool. This is the automatic safety locking device for the outer door.
The output points of the outer door security configuration are explained as follows:
1: Spring type automatic door closing: when opening the door, a greater torsion is required to pull the door, that is to say, when opening the door, the tension spring needs to be lengthened and run to the opening limit switch signal (opening is completed). At this time, the outer door has been affected by the pulling back of the tension spring, and the torsion of the elevator door motor is at the maximum. At this time, the door machine motor must be replaced with stationary torsion function, and stops at the opening completion function. When closing the door, the door motor machine must be replaced by the running brake function due to the pull back of the tension spring. If the running brake function is not used, the door closing will have an impact sound. Because the pull back force of the spring is getting smaller and smaller,therefore,it is necesssary to have the the compensation function of end speed, so that there will be no hard closing speed curve.
2: Counterweight type automatic door closing: it takes a lot of torsion to open the door. When the door is in place, it will be affected by the counterweight pulling back, and the door is pulled backwards. At this time, the elevator door motor must have a stationary torsion to keep the door fixed in position. The door closing is in the opposite direction. Affected by the maximum falling of the counterweight, theelevator door motor must be replaced with the brake function. When the door is in place, there will be no inertial impact.
3: Closing completion torsion: when the car is about to leave the floor, the inner and outer doors have been closed. At this time, the door machine motor needs to be turned to a stationary torsion to keep the car door from being affected by external forces. This is the safety laws and regulations of elevators.
4: Opening completion torsion: when the car reaches the floor, in order to make the people enter and exit without obstacles, at this time, the door machine motor needs to be turned to open the door to complete the torsion and keep the elevator door fully opened. This is the function of the elevator.
From the above points we can know that the elevator door machine is a very special moving body. Only dedicated synchronous motors with special functions can be competent.