How Do Office Chair Hydraulics Work?

Most modern office chairs use hydraulics or ‘pneumatic’ lift mechanisms that allow the user to move the chair up and down easily. This enables them to use the science of ergonomics.

What is Ergonomics? 

Ergonomics is a combination of disciplines such as anatomy, physiology, psychology and engineering. Essentially, it’s concerned with how people interact with their environment and the ways the environment can be changed to ensure safe and effective working practices. For example, ergonomics can be applied to physical objects such as chairs and desks, or it could be applied to a system, such as communications between different departments. 

Ergonomic chairs

An ergonomic chair is designed specifically to support the body during long periods spent sitting. They have many features that are designed to improve posture and comfort and to help support the health of the user whilst they are working at a desk. These ergonomic chairs usually have mechanisms to help to adjust the seating positions quickly and easily – using hydraulics via a lever below the chair.

What does the term ‘hydraulics’ mean?

Hydraulics – and pneumatics – are the terms used for applications of fluid power. Hydraulics uses incompressible liquid metal (such as oil) to enable machinery movement, and pneumatics use an easily compressible gas such as air (or a pure gas) to enable the same functionality. Hydraulic systems can move heavy loads, however, pneumatic technology is cleaner, used for lighter loads (such as office chairs), and is both safer and easier to store. Both systems use the same technology, however, pneumatics are generally used for office chairs.

How does a pneumatic system work?

Pneumatic chairs are adjustable using a lever generally situated just below the seat. This lever moves the seat up and down in a fluid motion. But how does this work? There are quite a few components that are incorporated into a pneumatic chair! They are:

• The chair base (usually three, four or five wheels);
• a gas cylinder that stores the compressed air;
• a seat that is covered with a plate holding the adjustable lever;
• a padded back support

What is a gas cylinder and how does it work?

Gas cylinders, or pneumatic cylinders, are devices that take the pressured power of compressed gas and force it through a chamber which then moves a piston in the required location. This movement and force enable the office chairs’ seats to rise or lower down. When the lever on the chair is pressed, the gas is pushed in and out of the chamber, facilitating this movement. 

Why has your office chair stopped moving?

If an office chair is used every day and is quite old, the height adjustment might be the first thing to go. If your chair won’t go up or down, it is usually because of a faulty gas cylinder, or due to a lift mechanism that won’t work. Depending on how old the chair, you could either send it back to the manufacturer, fix it yourself or…

Would you like a new office chair?

We have a fantastic range of office chairs. Whether you’re looking for leather office chairs, fabric office chairs or office chairs for under £100, you’ll find a host of chairs to suit you at Manutan UK.