Office Chair Base Hole
Office chair base holes can be classified into traditional and improved structures, and there are also relevant points to note during assembly.
Traditional Base Hole Structure and Issues
The tapered hole in the base of a traditional office chair plays a crucial role in connecting the chair base to the legs. The air pressure valve at the top of the air cylinder is nested within this tapered hole. The manufacturing process involves creating a circular hole in the base and then welding a sleeve onto this hole to form the tapered hole. However, this welding method has several drawbacks. On one hand, the surface of the weld material at the joint between the base and the sleeve is uneven, with sharp protrusions that can appear. Weld spatter that falls onto other parts of the base can solidify and stick to the surface, easily scratching hands during assembly. On the other hand, false welding can occur when welding the tapered hole, which can lead to the hole detaching and pose a serious safety hazard to users.
Improved Base Hole Structure
To address the issues with the traditional structure, the improved tapered hole in the office chair base adopts a double-sleeve structure connected by riveting instead of welding. Specifically, a hole is first created in the base, with the first sleeve nested inside this hole. The second sleeve is then placed over the first sleeve, with the lower end of the second sleeve resting against the edge of the hole. The upper ends of the first and second sleeves are riveted together. The hole in the base is designed as a polygonal hole, with a wall extending inward from the hole. Reinforcing ribs are formed between this wall and the base, effectively enhancing the strength and stability of the base. The first sleeve has a complex structure, with a cylindrical upper end, a polygonal middle section that matches the hole in the base, and a protruding shoulder at the lower end. A circular through-hole is created in the center of the shoulder, which rests against the base. The polygonal middle section is positioned against the hole and wall in the base. The second sleeve is a circular ring-shaped sleeve with a circular support plate extending outward from its lower end, further improving the structural stability.
Base Hole Assembly Information
When assembling an office chair, place the base beneath the chair cushion, carefully aligning it with the four screw holes at the bottom of the cushion. Then, use the provided screws to tighten and secure the base. It is important not to overtighten the screws to allow for adjustments based on actual usage conditions later on.
