Chair synonyms Comfort. And this comfort is attained by a mechanism present in a chair. A Chair Mechanism is a mechanical component generally placed underneath an office chair, used for ergonomically personalizing the seating posture. This mechanism allows us to make essential adjustments to offer a convenient sitting experience in the long run.
With the help of multiple adjustment levers and knobs, you can easily control the movements of the seat and backrest, including seat height, seat depth, seat angle, and various tilts. In addition, chair mechanisms come in a variety of shapes and materials.
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However, the latest models might come with more advanced features, but the basic functionality remains the same irrespective of the mechanism.
- Chair Mechanism is crucial for making an office chair ergonomic and for the user’s overall well-being.
- Chair Mechanisms come in a wide variety range of materials, colors, and designs.
- Knee- tilt Mechanism particularly comes with the extra advantage of minimizing the weight load on the knees.
- Different types of Chair mechanisms provide unmatchable modifications and advanced features specially curated to the user’s needs.
Did you know? : The Centripetal Spring Arm Chair of 1849 was the first to include a mechanism.
Importance of Chair Mechanism
The significance of the mechanism in an office chair is directly related to the seating posture. Once you understand the ideal posture for sitting on your office chair, various chair mechanisms are great for making your office chairs more ergonomic and make the utmost sense.
Types of Seating Postures
There are preferably two types of Seating posture :
Right below here, is exactly what a static seating position looks like:-
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As you can see above in this image, the correct way of a static posture, you should keep in mind the following tips to achieve this:-
- Always ensure that an angle of 90° -100° forms between your thighs and back to minimize the pressure on your backbone.
- An angle of 90°-100° must be formed under your knees as well.
- The Backrest, Armrest, and lumbar support of a chair are equally vital.
- The feet should not hang; thus, they shall touch the ground or the footrest.
Unlike the static seating posture, the dynamic one allows you to frequently change the angle between the backrest and the chair seat. This is done with the help of various chair mechanisms.
Did you know? Dynamic Sitting has long been acknowledged as the global benchmark for ergonomic comfort.
Ideal Seating Posture
Ideal Seating posture is a myth.
This is because maintaining a static seating posture for a long time is inconvenient and may make your muscles tired, causing discomfort. As a result, you need to switch between static and dynamic seating postures occasionally.
However, a combination of static and dynamic posture emerges as an ideal seating posture.
Did you know why various mechanisms are in chairs essential?
This is the reason why, in 2008, decree law 81 was established, which declared that a “video terminal operator” (i.e., “someone who uses the computer for more than 4 hours a day”) needs a swivel seat on castors with adjustable height, lumbar adjustment, and backrest inclination movement mechanism.
Image via: Ergonomic accessories
To switch to different seating positions, other chair mechanisms prove to be of great use.
Therefore, it has been rightly said that- The chair mechanism is the heart of an Office Chair.
Interesting Read: Can Office Chairs Explode?
Prominent chair mechanism Types
Swivel and Tilt Mechanism
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The swivel and tilt mechanism is the primary mechanism present in an entry-level office chair. Hence, they are affordable and comparatively less expensive than other types of chair mechanisms.
The core function of this mechanism is to adjust the seat height by locking the seat height upwards or downwards.
In this type of mechanism, the tilt point is located in the center of the chair. Thus, it is also known as the Center tilt mechanism.
Another essential function of this mechanism is that while tilting, the angle formed between the seat and the backrest will generally remain the same (say, 1:1 or 2:2).
In addition, the swivel and center-tilt mechanism provides a single lock system where you can lock your sitting position, whether reclining backward or seated straight, as per your preference.
Image via:- Arielle Executive
In addition to the features present in the basic swivel and center-tilt mechanism, Knee- tilt Mechanism is a step ahead with the functionality of tilting frontwards.
This mechanism particularly comes with the extra advantage of minimizing the weight load on the knees. Whereas in the previous swivel or center-tilt, the pressure under the thighs increases when there is a backward tilt of the chair.
In this type of mechanism, the pivot point is located in the front of the chair. Thus, it is also known as the frontal pivot chair mechanism. This mechanism reduces the tension between your thighs and knees and doesn’t allow your weight to pressure your knees to lift from the ground while reclining backward on the chair.
Hence, it is a superior-quality office chair tilt mechanism that multiplies your comfort and relaxes the muscles in your legs.
Related Read: How to Keep the Office Chair From Rolling
Multi-function or Free-Float Mechanism
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A Multi-function or Free- Float Mechanism is a customized chair mechanism in which you can independently adjust or control the angle between your backrest and seat.
This is the most comfort-oriented and is best for ergonomic use. With the help of a multi-function chair mechanism, you can quickly obtain any seating posture- Static and Dynamic by adjusting your chair in every possible manner.
Forward tilt mechanism
One of them is a Forward glide tilt or forward tilt mechanism, which benefits your well-being.
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According to Occupational Safety and Health Administration (OSHA), a forward-sloping seat helps increase blood flow to the lower extremities and simultaneously reduces pressure in the lower back discs.
The below image is an example of the Multi-function office Chair tilt Mechanism :
Photo via:- desk and chair specialists
What makes the multi-function chair mechanism more special is its multi-position lock, along with a seat angle lock mechanism which can easily lock your chair in any desired position.
Did you know? All orthopedic office chairs use a Free-Float mechanism.
Synchronized tilt Mechanism
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The above image illustrates how a synchro tilt mechanism works.
As the name suggests, the Synchronized or Synchro-tilt mechanism works in sync between the seat and the backrest of a chair.
This is done by a mechanical tilt in this mechanism that allows the seat and the chair’s backrest to move in sync or a fixed ratio to each other. In this ratio, the movement of the backrest will always be relatively greater than the movement of the seat. Say, 2:1, 2.5:1, and so on.
For every 20% of the backrest movement, there is a necessary 10% movement of the seat, and that too in a synchronized manner.
Generally, Dynamic Sitting is promoted by a Synchronized or Synchro-tilt mechanism and Multi-function or Free Float Chair mechanism among all office chair tilt mechanisms.
Also Read: How to Clean Office Chair Smell?
Weight Sensitive Mechanism
Image via:- Desk & chair specialists
This one has to be my favorite of all time. Because of its minimalistic design and simplicity, the Weight Sensitive Mechanism is emerging as one of the prevailing chair mechanisms.
It is one of the most convenient to use since it has relatively less technicality to operate. Unlike other chair mechanisms, the weight-sensitive mechanism is free from complicated adjustment levers or knobs.
There is no lock system as it automatically activates and adjusts the seat height based on the user’s height, weight, or BMI (Body Mass Index).
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Apart from the five major chair mechanisms, there are a few more. Some of them are:-
Seat Slider Mechanism
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It is pretty clear from the name itself that Seat Slider Mechanism is appropriate only for seat adjustment. The core function of this type of chair mechanism is to make the seat of your office chair more or less deep with a seat angle lock mechanism.
As a result, you can continuously change the position of your seat for more comfort and a relaxed back. This helps to improve the angle between your hips and thighs, thus creating a better posture more frequently.
This mechanism has no association with the backrest; however, the basic function of adjusting the chair’s height, like every other mechanism, remains as usual.
Below is an example of a Seat Slider Office Chair tilt mechanism:-
Image via:- www.amplechairs.co.in
Permanent Contact Mechanism
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Like the seat slider mechanism, the permanent contact mechanism focuses on only one chair component. In the seat slider, the core concern was on the seat, whereas in Permanent Contact Mechanism, the core concern was on the chair’s backrest. This mechanism lets you lock the chair’s backrest in any desired position, whether inclined in front or reclined back.
This process of locking the backrest is called ‘Infinite lock.’ In addition, the height of the backrest can also be adjusted upward or downward, curated to your office chair needs.
Synchronous Frontal- Pivot Mechanism
This combines the Synchronous/ Synchronized mechanism and frontal pivot chair mechanism. Features of both these types of mechanisms are specially blended to give you an ergonomic experience.