EP3925490B1

EP3925490B1 - Ergonomic seating assembly

Info

Publication number: EP3925490B1
Application number: EP20180674.2A
Authority: EP
Inventors: Denes Levente; Movileanu Bogdan; Balázs BENCSIK; George Flutur; Daniel Cosovanu; Ionut-Danut Danci; Levente Nemes
Original assignee: Asociatia Cluster Mobilier Transilvan
Current assignee: Asociatia Cluster Mobilier Transilvan
Priority date: 2020-06-18
Filing date: 2020-06-18
Publication date: 2024-01-17
Anticipated expiration: 2040-06-18
Also published as: EP3925490A1

Description

Field of the Invention

This invention is generally related to the field of ergonomic devices and methods useful for improving posture. More specifically, this invention is related to ergonomic seating assemblies configured to support users with different body built in multiple postures.
More particularly, it incorporates office chairs that provide continuous full support of the body during seating by flexible back and seat panels, while the user performs various tasks over extended sitting periods and that provide independent and independently adjustable support to the back and seat.

Description of Prior Art

Seating ergonomics studies show that more than 50% of the employees in the EU perform high or low-skilled white-collar work, predominantly in offices. Prolonged sitting combined with reclining and sleeping results in a persistent contact of the body with cushions has various flexibilities. Statistics reveal the importance of ergonomic sitting since the right ergonom ic seating furniture with proper use can help reducing injuries and the so-called cumulative trauma disorders (CTDs), which often results from repetitive movements for extended periods. From an ergonomics point of view, the high comfort is related to the well-being, safety feeling and healthy sensation of the users.
One of the basic factors of sitting comfort is the specific pressure to the body, which is smaller when the contact surface of the human body is larger. Consequently, keeping the continuous contact of the body with the chair raise the comfort of a chair. Since chair users change frequently their posture during seating it is important that the contact surfaces, i.e. seat and back pans to follow the moving body.
A continuous human body-seat and back contact even for users with different anthropometric values can be assured by multiple adjustments like: gas spring for seat height adjustment; synchronous or asynchronous mechanism for tilting; spring for tilting flexibility; armrests adjustable in height, in depth, and in pivoting; lumbar support adjustable in height and in depth; adjustable seat plates in depth; adjustable back in height.
The present invention assures the continuous body contact with the chair and adapts to the dynamic body postures by multiple flexibility of the chairazs assembly.
Considering the prior art that we are aware of ( CN200910312940A , EP20050700742 ), the novelty from the technical point of view is that the invention relates to a chair seat and back assembly, more specifically two left and two right seat plates and two left and two right back plates and one head support fixed to wooden slats through elastic waisted vibration dampers. Multiple flexibility of the seat and back plates assured mainly by elastic vibrational dampers, arc spring or air springs keep the continuous contact between chair and user's body even in different postures. The constant contact provides a more uniform pressure distribution of the body mass, therefore a higher comfort can be achieved. The novelties of the presented solution are: the division of the seat into four which allows a flexible support at the bottom when the user changes the seating positions, the dividing of the backrest into 5 parts which allows a flexible support at the back when the user changes the seating positions. These divisions (seat + backrest) increase the adaptability of the seat and backrest to the anthropological differences of the body. Multiple flexibility of the seat and backrest: natural elasticity of the materials used (molded wood and / or compressed wood) + elasticity offered by the shape (curvature of the main column (spine), arching of the "ribs" + elasticity conferred by the solutions for connecting molded parts and divided by ribs, columnar ribs: by rubber or other elastic shock absorbers, air cushions, springs and combinations thereof. Other examples of known ergonomic seating assemblies are disclosed in KR200189719Y1 , KR100995964B1 , CN202312257U .

Summary of the Invention

The present invention refers to ergonomic seating assembly and methods configured to support users with different body built in multiple postures, office chairs with movable panels that provide continuous full support of the body during seating by flexible back and seat panels, while the user performs various tasks over extended sitting periods and that provide independent and independently adjustable support to the back and seat. By this movable panels the users are able to maintain a stable and constantly consistent posture. The present invention provides an ergonomic seating assembly as defined in claim 1. Preferred features of the invention are set out in the dependent claim.

Brief description of the drawings

The accompanying drawings, which are incorporated into, and form a part of the description, illustrate one or more embodiments of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings, numerals are used to describe similar components throughout the drawings:

∘ FIG. 1 provides an illustration of an isometric front view of the chair assembly
∘ FIG. 2 shows an isometric back view of the chair assembly
∘ FIG. 3 provides an illustration of side view of the preferred embodiment
∘ FIG. 4 shows the back view of the preferred embodiment
∘ FIG. 5 illustrates an isometric top view of the chair assembly
∘ FIG. 6 illustrates an isometric bottom view of the preferred embodiment
∘ FIG. 7a, 7b, and 7c show the cross-sectional view of the plurality of seating assembly configurations made possible by the assembling of modular components.

➢ Reference numerals:

1 - main column or spine from molded plywood or compressed wood
2, 21,22,23 - hand knobs
3, 31, 32, 33, 34, 35, 45 - cylindrical vibration dampers made of rubber, elastic resin or any other flexible material
5, 51, 52, 53, 54, 55 - curved slats or ribs from molded plywood or compressed wood
6,7 - insert nuts
8, 81, 82, 83 - waisted vibration dampers made of rubber, elastic resin or any other flexible material
9, 91, 92, 93 - waisted vibration dampers made of rubber, elastic resin or any other flexible material
10, 101, 102, 103 - back panels
11, 111, 112, 113 - back panels
104, 105, 114, 115 - seat panels
12, 13, 14 - T-nuts
15, 16 - arc springs
17, 18 - air springs

Detailed description of the invention

The embodiments of the present invention are described in detail with reference to the accompanying drawings. The invention relates to a chair seat and back assembly, more specifically two left and two right seat plates and two left and two right back plates and one head support fixed to wooden slats through elastic waisted vibration dampers.
The shape of the plates is symmetrical mirror (Fig. 1), the axis of symmetry is the vertical mid plane crossing the center of gravity. Seat and back plates have a three dimensional shape assuring a comfort fit to the users' body. The lower back plates 101, 111 have a convex form according to the normal inward curvature in the lumbar region of the human spine. The upper back plates 102, 112 have a concave form to fit to the normal outward curvature of the thoracic spine region. The head support 103 at the top has also a convex form in order to assure a comfort support of the head near the cervical lordosis. The seat and back plates and the head support as well can be made of molded plywood or other reinforced bio-composites. For a higher comfort the plates can be upholstered using foams, stuffing and padding materials, covered by various fabrics.
The seat and back plates and the head support plate are fixed to curved wooden slats called also ribs through elastic vibration dampers. The front seat plates 105, 104 and rear seat plates 104, 114 are fixed to the front rib 55 and rear rib 54 respectively across cylindrical vibration dampers 34, 35, 44, 45. The elasticity of dampers are controlled by the chosen material elasticity and geometry. These cylindrical dampers make possible the limited rotation of the seat plates around two axes (back and forth, left-right). The cylindrical dampers are fixed to seat plates and ribs by T-nuts 12, 13, 14 or insert nuts 6,7 in function of the dampers design (threaded bush or stud on one or both sides). Both the convex 101, 111 and concave 102, 112 back plates and the head support are joined to ribs using waisted vibration dampers.
Due to the use of these dampers the back plates can rotate up and down and left and right respectively. The flexibility of the plates is controlled by the elastic properties (Shore hardness) and geometry of the dampers (diameter and concavity).
The back plates are adjustable in width due to the slots cut in ribs. The back ribs 51, 52, 53 are joined to the main column or spine 1 through T-nuts 14 and bolts 2. To increase the flexibility of the back plates cylindrical dampers similar to those used on the seat 34, 35, 44, 45 can be used additionally. Instead of waisted vibration dampers, arc springs 15, 16 or air springs 17, 18 can be used as alternative solutions.
The spine 1 as the main structural element of the chair assembly is made of molded plywood or compressed wood and is fixed to the swivel chair base with the help of nuts and bolts. The curved slats or ribs of the back 51, 52, 53 are adjustable in height using hand knobs 21, 22, 23. The adjustability of the ribs is limited by the length of the slots manufactured in spine 1. The shape of the spine 1 imitates the human spinal column, the curvatures (cervical and lumbar lordosis, thoracic kyphosis) follows the CBP ^® Full Spine Model combined with own measurements. The lower curvature of the spine assures the flexibility of the full back assembly.
Height-adjustability of the ribs and width-adjustability of the back plates offer to the chair users a high comfort, since anyone can fit these plates according to their own anthropometric data assuring a perfect contact between the body and the chair assembly.
The multiple flexibility of the seat and the back plates is ensured mainly by the elastic vibration dampers and the arc springs or air springs maintain the continuous contact between the seat and the user's body even in different positions. The constant contact provides a more uniform pressure distribution of the body mass, therefore a higher comfort can be achieved.
The flexibility of the chair is controlled by numerous factors: the intrinsic elasticity of the used materials:

modulus of elasticity of the wood species used or modified modulus of elasticity of the compressed wood, or reinforced laminated wooden composites
modulus of elasticity of the rubber used for vibration dampers
modulus of elasticity of the steel used for arc springs
air pressure in the air springs
geometry, thickness, width, radius, arc length of the wooden parts (spine, ribs)
diameter, waisted diameter of the vibrational dampers
diameter, number of active coils, wire diameter, pitch of the arc springs
adjustability of the chair assembly, height-adjustability of ribs, width-adjustability of the plates

The invention is not limited to the details of the foregoing illustrated embodiments and the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative-and not restrictive-the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
As stated above, the novelty elements are given by the multiple flexibility of the seat and back plates assured mainly by elastic vibrational dampers, arc spring or air springs keep the continuous contact between chair and user's body even in different postures. The constant contact provides a more uniform pressure distribution of the body mass, therefore a higher comfort can be achieved. The novelties of the presented solution are: the division of the seat into four which allows a flexible support at the bottom when the user changes the seating positions, the dividing of the backrest into 5 parts which allows a flexible support at the back when the user changes the seating positions. These divisions (seat + backrest) increase the adaptability of the seat and backrest to the anthropological differences of the body. Multiple flexibility of the seat and backrest: natural elasticity of the materials used (molded wood and / or compressed wood) + elasticity offered by the shape (curvature of the main column (spine), arching of the "ribs" + elasticity conferred by the solutions for connecting molded parts and divided by ribs, columnar ribs: by rubber or other elastic shock absorbers, air cushions, springs and combinations thereof.
It should be emphasized that the described embodiments are possible examples of implementations, merely set forth for a clear understanding of the principles. Variations and modifications may be made to the described embodiment(s) without departing from the scope of the present claims. All such modifications are intended to be included herein within the scope of the present invention and protected by the following claims. The present disclosure is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.

Claims

An ergonomic seating assembly configured to support users, with movable back and seat plates (10, 11, 101, 102, 103, 104, 105, 111, 112, 113, 114, 115) that provide continuous full support of the body during seating by flexible back and seat plates (10, 11, 101, 102, 103, 104, 105, 111, 112, 113, 114, 115), the ergonomic seating assembly comprising:
a slotted main column (1) called spine (1) having a form if a human spinal column,

a slotted curved cross slats or ribs (5, 51, 52, 53 54, 55)

a seat having four flexible seat plates (104, 105, 114, 115) with a 3D geometry

a back having five flexible back plates (10, 11, 101, 102, 103, 111, 112, 113) two of them with convex shape (102, 112) according to the lumbar lordosis of the normal human spine, two of them with concave shape (101, 111) fitting to the normal thoracic kyphosis of the spine, and the fifth convex plate (103) to support the cervical lordosis,

a flexible connection between the spine (1) and the slotted curved cross slats or ribs (5, 51, 52, 53, 54, 55) using vibrational dampers (3, 31, 32, 33, 34, 35, 45) or air cushions

a flexible connection between the back plates (10, 11, 101, 102, 103, 111, 112, 113) and the slotted curved cross slats or ribs (5, 51, 52, 53, 54, 55) using waisted vibrational dumper or springs/ air cushions (8, 9, 81, 82, 83, 91, 92, 93)
The ergonomic seating assembly of claim 1 made of molded plywood, bent wood, compressed wood or reinforced wood based composites.