The knee tilt mechanism is a twin lever mechanism with the levers usually located underneath the seat pan. The first lever (usually found on the right) allows the user to adjust the height of the chair up and down. One of the best ways that users can identify whether they are in the correct height position, is to ensure the height of the chair allows them to have their feet flat on the ground with their knees at a 90-degree angle whilst sitting on the seat.
The remaining lever (usually found on the left) can lock the chair in position or can be left for the chair to tilt with the user.
The pivot point of the seat is found further forward than usual which makes chairs with this function more accessible for people with different heights and helps maintain a good posture whilst ensuring that the user’s feet are kept flat to the floor no matter what position the chair is in. Additionally, this function is normally fitted with an anti-shock device that means that the user is not thrown forward when the chair returns from a reclined position when it is unlocked.
The added function of a torsion control knob can also be found accompanying the knee tilt mechanism that allows the user to adjust the tension on the springs of the chair to match their body weight. Tightening the knob will give more resistance to the back of the chair which will prevent users from unintentionally leaning back. An adjustable lumbar support can be present on these chairs to give extra support if required.
Finally, an adjustable head rest is usually available to cater for users of different heights so that the head and the neck are supported at all times.
What are the Differences in Chair Mechanisms?
Listed below are a list of the most common chair mechanisms and how they differ:
Synchronous Mechanism – The synchronous mechanism combines a larger movement of the seatback and a corresponding smaller movement of the seat pan.
Permanent Contact – Permanent Contact is where it is possible to move the backrest forward and backwards. The seat can’t be tilted independently of the backrest.
Basic Tilt Mechanism – Where the seat, armrests and backrests tilt as one. The whole chair is tilted when you lean back. No individual part can be tilted independently of one another.
Weight Controlled – An adjustable weight-controlled mechanism is fitted which increases or decreases resistance of the seatback depending on how it is adjusted to match the user’s body weight.
Body Balance – The seat of the chair moves like the user is sitting on an exercise ball. Through their muscles the user is kept upright. The Body Balance System is designed to not put as much pressure on the spine and therefore prevents back pain.
Lumbar Support – These chairs are fitted with a back and seat that promote proper alignment of the lower back. These are extremely beneficial for users who spend all day sitting at their desk.
Why Should I Buy an Adjustable Office Chair?
Sitting in the wrong chair in your office can be affecting more than just your comfort. Awkward posture, excessive force, repetitive work, contact stress and static exertions all contribute to potential musculoskeletal disorders. Musculoskeletal disorders account for nearly 40% of all workplace injuries in the UK. In 2017-2018 it accounted for 6.6 million lost work days. This will go on to contribute huge losses in compensation costs, lost wages to workers and lost productivity. A lot of these can be prevented with the right workstations accessible to employees.
Providing ergonomic office chairs and the training to use them can decrease soft tissue injury and an increase in work place productivity. An adjustable chair gives users the freedom of movement throughout the day, even in a seated position. Coupled with regular breaks, this increases blood flow to the brain and the body, leaving workers feeling motivated and energized whilst they’re at work.
The application of Ergonomics in the workplace increases productivity. Employees are the most valuable asset to a business so it is important to provide them with the best workstation so they are able to do their best work. When employees aren’t experiencing fatigue and discomfort during their work-day they are more likely to achieve excellent attendance, show more commitment to their work as well as an increased morale and engagement.
What is tilt lock in a chair?
This is where a chair locks out when in the upright position to stop it from going back.
What is a standard seat height?
Chair height is generally 18 inches from the floor to the seat.