Choosing the Right Office Chair: Type of Mechanisms
When shopping for a new Office Chair, it is important to know the different types of chair mechanisms that are available in the market, as they affect your seating experience. An office chair mechanism is the mechanical component attached to the bottom of an office chair giving it different adjustment and movement functionalities.
These office chair mechanisms come in different shapes, materials, can be from different brands and can have a few additional features depending on the model, but their basic functionalities will all be the same. Currently, there are 5 main types of chair mechanisms in the office chair market:
 Swivel & Tilt Mechanism (or Centre Tilt Mechanism)
The Swivel and Tilt Mechanism is the most common type of mechanism and are used in entry-level office chairs. They are therefore the most affordable office chair mechanism.
This first basic movement that this mechanism allows, is the upwards and downwards adjustment of the seat height. The second functionality the Swivel and Tilt mechanism allows is a backward tilt or recline of the chair when putting your weight backwards.
The point of the tilt movement is at the centre of the seat and the angle between the backrest and the seat will remain the same while tilting backwards. The mechanism also has a 1 position lock enabling you to lock the seat in the normal position in order to prohibit any backwards tilt movement. Swivel and Tilt mechanisms usually have a tension adjuster that allows you to adjust the tension of your tilt movement, making it slightly easier (or harder) to recline backwards.
While the Swivel & Tilt mechanism is your most cost-effective mechanism, it does come with 2 disadvantages:
- Since the point of the tilt is in the centre of the seat, the majority of your weight in the tilt position is in front of your legs. This means that your knees will move upwards, and your feet will lift off the ground when reclining backwards.
- Due to the above, you also have to use a lot of effort when trying to tilt the chair backwards.
Example of Swivel & Tilt Mechanism
 Knee-tilt Mechanism
The knee-tilt mechanism is a ‘one-up’ from the Swivel & Tilt mechanism and is usually used in your mid-level office chairs or Managerial and Executive Office Chairs.
This mechanism will have the basic functionality of adjusting your seat height upwards or downwards. Similar to the Swivel and Tilt mechanism, you are also able to tilt or recline your seat backwards when applying weight to the backrest.
The mechanism will have a 1 position lock allowing you to lock the chair in its normal position, thus prohibiting a rear tilt movement. It also comes with a tension adjuster enabling you to adjust the tension of your recline motion, making it slightly easier (or harder) to tilt backwards.
The point of difference with a Knee-tilt mechanism is that the point of recline is now moved from the centre, to just behind the knees. The weight therefore shifts from in front of the legs, to behind the legs. This means that you are able to tilt backwards using less effort, and more importantly, that your feet and knees will not lift off the floor when tilting. Consequently the Knee-tilt mechanism will create a more comfortable and effortless seating experience for the user.
Example of Knee Tilt Mechanism
 Multifunction Mechanism
The Multifunction Mechanism is a lockable mechanism used in mid to top level office chairs, and Managerial and Executive office chairs.
This mechanism will also have the basic function of adjusting the seat height upwards or downwards. Similar to the previous mechanisms, the Multifunction mechanism enables the user to tilt or recline their chair backwards when applying weight to the backrest. The mechanism will also have a tension adjuster allowing you to adjust the tension of your recline motion, making it slightly easier (or harder) to tilt backwards.
Similar to the Knee-tilt mechanism, the point of recline in the Multifunction mechanism is just behind the knees. The weight is therefore behind the legs, and enables the user to tilt backwards using less effort, and without causing the knees or feet to lift off the floor when tilting.
What separate the Multifunction mechanism from the Knee tilt mechanism are 2 main features. The first, and most common, is a multi-position lock. The Multifunction mechanism allows the user to lock the chair in various positions that range from the normal upright position, to the back tilt, front tilt and anywhere in between.
The second functionality in some Multifunction mechanisms is the ability to move and lock the backrest separately from the chair. You are therefore able to first move the backrest individually into a position you prefer, lock it, and then tilt your chair backward and forward as a whole.
These functions provide the user with more control over their seating experience.
Example of Multifunction Mechanism
 Synchro Tilt Mechanism
The Synchro Tilt Mechanism is used in mid to high end ergonomic office chairs.
The mechanism will have the basic function of an upward or downward adjustment of the seat height. Similar to the previous mechanisms, the Synchro Tilt mechanism allows you to tilt or recline your chair backwards when applying weight to the backrest. The mechanism will also have a tension adjuster enabling you to adjust the tension of your recline motion, making it slightly easier (or harder) to tilt backwards.
What sets this Mechanism apart is that the seat and backrest move at different angles when tilting or reclining backwards. This is done in a 2:1 ratio, for example if the backrest is moved 2 inches backwards, the seat will only tilt 1 inch. This functionality keeps you in an ergonomic position while you tilt, also without lifting your feet off the ground. It furthers makes reclining easy and creates a more fluid motion.
The Synchro Tilt mechanism will not have a rocking motion when tilting backwards, as it is specifically built for ergonomic purposes. The mechanism does come with a multi position lock allowing the user to lock the chair in various positions that range from the normal upright position, to the back tilt, front tilt and anywhere in between.
The Synchro Tilt mechanism is therefore suited to users who value ergonomics and who want to have more control over their movement.
Example of Synchro Tilt Mechanism
 Weight Sensitive Mechanism
The Weight Sensitive Mechanism is used in mid to high level ergonomic office chairs, but the use in entry level office chairs are becoming more evident as well.
The first basic functionality of the mechanism is the upwards and downwards adjustment of the seat height. The point of difference in the Weight Sensitive mechanism is its simplicity:
The mechanism has a simplistic, clean and minimalistic design, making it extremely easy to use. It does not come with any levers or knobs and has no lockable function. Instead, the Weight Sensitive mechanism will automatically recline and adjust to put you in the best ergonomic position for your body, when tilting or moving in the office chair. This position is based on your height, weight and how you are positioned in the chair at any given moment.
The main attraction is its user friendliness. As the user, you don’t have to know how any of the mechanism components work or how and where to adjust them. All you have to do is sit, and the mechanism works for you.
Example of Weight Sensitive Mechanism