How much external force can the elevator door be forced to open?

Li Zhong, director of the Hangzhou Special Equipment Emergency Response Center, said that the elevator has two doors. The one that can be seen from outside the elevator and is fixed on each floor is called the hall door (door leaf), and the one that can be seen from the inside is called the car that moves along with the movement of the car. Door. However, when the car door and the hall door are not on the same floor, the hall door may indeed be forced to open and cause an accident under the impact force or special circumstances!

How do elevator doors work

An employee of elevator brand A said that the car door is an active door, and the hall door is a passive door. When the car door is opened or closed, the door motor on the top of the car is mainly connected with the belt to drive the door knife on the car door (equivalent to on a rectangular metal frame) to open or close the car door.

When we get on and off the elevator, we usually press the elevator button first. When the indicator light is on, the hall door and the car door are opened at the same time before we can enter.

When the car door accepts the system command (through the button), the car door will move up and down to the hall door of the designated floor, and the door knife on the car door will pass through or out of the door ball on the hall door to realize the car door and the hall. The door opens and closes at the same time.

Under normal circumstances, if no command is received, the elevator hall door will not be opened. There is a triangular keyhole on the hall door. Only the elevator management personnel can open the hall door under abnormal conditions.

How resistant is the hall door to pressure?

So, how resistant is the hall door to pressure? An employee of elevator brand B said that the hall door is usually made of iron or stainless steel. If an ordinary person weighing 150 pounds kicks three or four feet with the greatest force, it may break the hall door.

However, this assumption may be a bit exaggerated, said Li, director of the Hangzhou Special Equipment Emergency Response Center. Director Li said that according to the current "Safety Specifications for Elevator Manufacturing and Installation", when the elevator landing door (ie the hall door) and its door lock are in the locked position, they should have such mechanical strength: that is, a force of 300 Newtons acts vertically on the elevator. The safety function of the door shall not be affected when the hall door is evenly distributed on a circular or square area of 5 square centimeters at any position on any surface of the hall door.

A force of 300 Newtons acts uniformly on an area of 5 square centimeters. What is the effect? The physics teacher of Hangzhou No. 2 Middle School, Mr. Zhao, did the math and said that the pressure generated by this force is equivalent to 6 times the atmospheric pressure, and it is also equivalent to the pressure that a person bears at a depth of 50 meters.

Several professionals have specifically stated that the most vulnerable position of the elevator hall door is at the bottom. There are two chutes at the bottom of the hall door, which are a bit like the chutes we saw when swiping cards. The hall door is opened or closed against these two chutes. And fixed on each floor. When the hall door is subjected to a certain impact force, the closer the force point is to the chute, the more likely the hall door will be damaged. When the chute cannot withstand the external force, the hall door may be knocked open. Sex will naturally increase.