Office Chair Lifter Structure Diagram
The structure of an office chair lifter (pneumatic rod) mainly consists of six parts: the outer tube, inner tube, piston, seal, gas spring, and control valve, which work together to achieve the seat lifting function.
Outer Tube and Inner Tube: The outer tube is a high-strength metal tube (usually cold-rolled steel or aluminum alloy), with the inner tube nested inside. The two are isolated by precision seals to form a sealed air chamber. As the main structural component, the outer tube needs to bear the weight of the seat and the occupant, so it must have high strength and corrosion resistance; the inner tube achieves lifting and lowering through sliding, and its surface needs to be smooth to reduce friction.
Piston: Located at the bottom of the inner tube and connected to the gas spring. The piston regulates the air pressure difference inside the air chamber through the control valve: when the control valve is opened, high-pressure gas enters from one side of the air chamber to the other, pushing the piston to move and thereby driving the inner tube to lift or lower; when closed, the air pressure difference locks the piston in place, fixing the seat height. The sealing performance of the piston directly affects the lifting stability and requires the use of wear-resistant materials.
Seal: Usually made of pressure-resistant materials such as nitrile rubber, used to isolate the outer tube and inner tube. Its core function is to prevent gas leakage (which would cause lifting failure) or the entry of impurities (which would wear down components). The seal needs to have high elasticity and aging resistance to adapt to long-term compression and temperature changes.
Gas Spring: It is the core elastic component of the lifter, composed of a stand tube, outer tube, cylinder tube, and piston. The stand tube fixes the piston rod and transfers the gravity to the five-star base; the outer tube connects to the chair chassis and forms a sealed air chamber with the cylinder tube and piston head to store high-pressure gas; the inner side of the cylinder tube slides in contact with the piston head, and together with the oil seal, forms two non-directly connected air chambers, achieving cushioning and lifting through air pressure differences. The performance of the gas spring (such as pressure value) directly affects the load-bearing capacity and lifting smoothness of the seat.
Control Valve: Usually located at the top end of the gas cylinder and controlled by a height adjustment lever. When the adjustment lever triggers the control valve, the air pressure balance inside the air chamber is disrupted, and the piston moves to drive the seat to lift or lower; after release, the valve closes, and the air pressure difference locks the current height. Some control valves also integrate a safety lock function to prevent accidental lifting or lowering.
