Office Chair Bottom Knob

The knob at the bottom of an office chair is primarily used to adjust the chair's height, backrest elasticity or tilt angle, as well as control the extent and elasticity of the chair's backward tilt. Here are the specific functions:

Adjusting Chair Height: This is the most common and basic function of the knob at the bottom of an office chair. The knob is connected to a gas lift cylinder filled with high-pressure nitrogen gas. When the knob is turned, the piston inside the gas lift cylinder starts to work, utilizing pressure differences to raise or lower the chair. People of different heights have varying requirements for chair height. By adjusting this knob, individuals can set the chair to the most suitable height for themselves, allowing their feet to rest flat on the ground with their thighs parallel to the ground, thereby maintaining proper sitting posture and reducing physical fatigue. For example, taller individuals can raise the chair to avoid bending over for long periods, while shorter individuals can lower the chair to ensure their feet can rest comfortably on the ground.

Adjusting Backrest Elasticity or Tilt Angle: In some more advanced computer chairs, in addition to adjusting the height, the bottom knob can also adjust the backrest's elasticity or change the chair's tilt angle. If the chair is equipped with a small lever or control rod, the large knob is usually dedicated to height adjustment, while the small lever is used to adjust the backrest's elasticity or tilt angle. By adjusting the backrest elasticity, individuals can provide appropriate support force for the backrest when leaning back according to their body weight and comfort needs. Adjusting the tilt angle allows people to set the chair to different tilted positions, such as semi-reclined or upright, based on their work or rest requirements.

Controlling the Extent and Elasticity of Backward Tilt: Some knobs at the bottom of office chairs can also control the extent and elasticity of the chair's backward tilt. When the knob is tightened, the extent to which the chair tilts backward decreases, and the rebound elasticity increases. Conversely, loosening the knob increases the extent of backward tilt and weakens the rebound elasticity. However, when using this function, it is important to note that the knob should not be tightened too much, as this may cause the knob to break and damage the chair.