Nowadays, in the office or in the study room of our home, in addition to the sofa, we can see the chair lift, and the bar chair shop can see the existence of the chair lift. The chair has been used in many corners of our lives. Do you understand the principle of using a chair that is so widely used to adjust the height of the chair?
What is a chair lift:
The chair is a general term, which refers to a swivel chair with adjustable height of the chair and a horizontal rotation of the chair. People usually refer to it by rotating chair, swivel chair, computer chair, office chair and so on. Since the seat under the seat has a lifting device for adjusting the height, the seat surface can be raised and lowered. Depending on whether the lifting device used is pneumatic or hydraulic, the lifting chair is divided into two types: a pneumatic Lift Chair and a hydraulic lift chair.
The working principle of the chair lift:
The lifting of the chair is mainly realized by the lifting device at the lower part of the chair. The current lifting devices are mainly divided into three categories: oil pressure, mechanical type and air pressure. The pneumatic lift chair is the most common chair lift. The pneumatic lift chair has a gas pressure bar. The gas pressure bar is a working medium with gas and liquid. It can support, buffer, brake, height adjust and adjust the angle. The basic principle of the functional elastic element is that the internal pressure is filled with high-pressure nitrogen. Since the through hole is provided inside the piston, the gas pressure at both ends of the piston is equal, and the cross-sectional areas on both sides of the piston are different, one end is connected with the piston rod and the other end is not. Under the action of gas pressure, the pressure on the side with a small cross-sectional area is generated, that is, the elastic force of the gas pressure bar. When the person sits up to the pressure of the lifting shaft, the lifting shaft is gently lowered, and the speed is uniform, and can be lowered to the lowest point. Without lifting the shaft, the lifting shaft is raised back to the highest point. Regular manufacturers are filled with nitrogen, the concentration is generally above 99%, and the pressure is around one or two atmospheres.
The function of the lifting device of the chair lift:
1. When the lift valve switch is pressed, the person sits up, that is, the pressure of the lifting shaft, the lifting shaft is gently lowered, the speed is even, and can be lowered to the lowest point; if there is no person on the chair, or the seat is not given Applying a downward external force, the lifting shaft immediately bounces back to the highest point, which is slightly faster, less than a second.
2. When the valve switch is released without pressing or pressing, the lifting shaft is kept at the current position, and neither compression nor stretching can move it relative to the outer sleeve.
Freestyle gas spring:
The free-form gas spring is simple and consists of three components: a closed cylinder, a piston in the cylinder, and a piston rod that extends to the outside. The air pressure inside the cylinder is larger than the atmospheric pressure outside, and there are small holes on both sides of the piston inside the cylinder. According to the knowledge of middle school physics, if the piston rod is pressed inward, the resistance is constant, that is, the difference between the air pressures at both ends of the piston rod.
The self-locking type is a free-form piston rod with a shaft inside, and the innermost end of the shaft is connected with a valve to control the communication hole of the piston portion. When the valve is pressed, the communication hole is provided, which is equivalent to a free-form type; when the valve is popped up, the communication hole is lost, and it will be locked.
Note: The cylinder is our outer sleeve; the piston is our lifting shaft; the shaft in the piston is our valve button switch.
Why does the ▽ pneumatic lift swivel chair explode?
The chair is a commonly used swivel chair that controls the lifting of the seat by a pneumatic lever. The seat is divided into three parts: a seat cushion, a pneumatic rod and a runner. There is a cylinder inside the gas pressure rod, and the piston rod in the cylinder moves up and down to support the swivel chair. The gas pressure bar is filled with nitrogen. The principle of a pneumatic chair is like a balloon that has not reached the critical point of the explosion. When it is squeezed, the internal pressure accumulation increases, and when it exceeds the critical point, it may explode.
How do you prevent the chair from exploding?
1. The pressure bar of the chair is mainly raised and lowered by high-pressure nitrogen. Generally, the purity of the gas is less than 90%. There may be safety hazards. Some manufacturers will inject high-pressure air or other gas into the gas pressure rod to save the cost. The safety is greatly reduced.
2, the seal is not tight, it will also cause an explosion.
3. The firmness of the wall material of the gas pressure rod container will directly affect the safety of the chair.
How do you avoid the explosion of a chair lift?
1, to choose regular furniture brand products. If you buy a product with a qualified mark, don't buy cheap goods.
2, buy the swivel chair, first look at the plastic floor of the swivel chair is not strong, and then slide the swivel chair back and forth, the quality of the swivel chair is more flexible, no tilt.
3. When the chair is in use, do not rotate it repeatedly. After using it for a period of time, it should be checked in time. Once cracks and loose signs are found, it should be repaired and replaced in time.
4, weight more than 100 kg sit carefully.
Related reading: What kind of seat is good for your health? What conditions should a healthy chair meet?
