NZ567503A

NZ567503A - Back support for a chair using a gel filled pouch that adjust in response to pressure from the users spine

Info

Publication number: NZ567503A
Application number: NZ567503A
Authority: NZ
Inventors: Robert Andrew Crosbie
Original assignee: Robert Andrew Crosbie
Priority date: 2005-09-16
Filing date: 2006-09-15
Publication date: 2011-04-29
Also published as: US20090051199A1; AU2006292038B2; WO2007030893A1; AU2006292038A1; CA2622572A1; EP1933670A1

Abstract

A back support (18) for a chair (10) is disclosed. The back support (18) conforms to the spine of the user. The support (18) has a body (22) for receiving a back of a user when the user is in a seated position on the chair (10). Within one or more elongate recesses in the body (22), two or more shape adaptive members (32), being pouches filled with gel, respond to pressure applied by the back of the user to conform to the user. The least two shape adaptive members (32) are separated by a gap, each shape adaptive member (32) is a generally elongate strip located in the at least one elongate recess. Each shape adaptive member (32) is adapted to support a region of the user's back proximal the transverse processes of the user's vertebral column and the gap is adapted to receive a region of the user's back proximal the spinous processes of the user's vertebral column.

Description

Received at IPONZ 15 March 2011 1 "Back support for a chair" Cross-Reference to Related Applications The present application claims priority from Australian Provisional Patent Application No 2005905152 filed on 16 September 2005, the content of which is incorporated herein by reference.

Field of the Invention The present invention relates to a chair and in particular to a back support for a chair which provides adjustable support to the vertebral column of a seated individual.

Background Art In modern society, people spend an increasing amount of time in a seated position. In most office environments and workplaces, more and more people are being employed in positions where their daily duties are desk orientated and they spend the majority of their day seated at their own workstation. Further, with the popularity of 20 television and video games and the like, many individuals are also spending a great deal of their leisure time in a seated position.

Given such a large amount of time spent by individuals in a seated position, it is important that they are provided with chairs that are comfortable and provide sufficient 25 support to ensure correct posture as well as to reduce stress on the individual's back and prevent any back related problems from developing. In this regard, one of the most important features of any chair is in the manner in which the chair supports the user's back. Should a chair provide inadequate support, or support the back in an improper position, the user may become uncomfortable after sitting for a prolonged period of 30 time. This can in turn contribute to chronic back problems, which can easily be avoided through correct back support.

The human back differs in size, shape and strength from individual to individual, and as a result the ideal type of back support will also differ from individual 35 to individual. Unfortunately, most available chairs are typically designed with the back support sized and shaped to accommodate an average person having an average build, Received at IPONZ 15 March 2011 2 and hence do not suit all individuals. In this regard, most office type chairs are provided with various adjustment mechanisms to adjust the height and position of a variety of features of the chair, such as back support angle and height, however whilst this allows a variety of different configurations of the chair, they are typically limited in 5 range and not always adjusted according to the correct postural needs of the individual.

In this regard, there is a need to provide a chair which employs a back support that is readily conformable to the back of a variety of individuals to support the individual's spine in a manner which optimises weight distribution and/or which cradles 10 the back to reduce pressures being transferred to the user's spine.

Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of 15 these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.

Summary of the Invention Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps, In a first aspect, the present invention is a back support for a chair, comprising; a substantially vertical foam body having a support surface for receiving a back of a user when said user is in a seated position on said chair, the foam body having at least one elongate recess formed in the support surface, the at least one elongate recess 30 extending in a substantially vertical direction at a central region of the support surface; and at least two shape adaptive members separated by a gap, each shape adaptive member being a generally elongate strip located at least partially in the at least one elongate recess; wherein the shape of each shape adaptive member is variable in response to pressure applied thereto by the back of said user when said user is in said seated Received at IPONZ 15 March 2011 3 position; and wherein, when the user is in said seated position, each shape adaptive members is adapted to support a region of the user's back proximal the transverse processes of the user's vertebral column and the gap is adapted to receive a region of the user's back proximal the spinous processes of the user's vertebral column.

The foam body may comprise foam proximal said support surface which is soft and flexible, to provide comfort to the user. In one form, the support surface may be a substantially flat surface. In another form, the support surface may be contoured to conform to the user's back.

One or more of the shape adaptive members may be in the form of a pouch containing a quantity of gel material. The gel material may be a hydrogel or a polymer gel. In one form, the gel material may be a viscoelastic polyurethane gel. The pouch containing the gel material may be a polyurethane film material which assumes the 15 shape of the gel material contained therein. In this regard, the shape of the pouch may readily change in response to pressure applied thereto by the back of the user. Such pressure causes a change in the distribution of the gel within the pouch. The pouch may be in the form of an elongate strip of gel material.

The shape adaptive members may extend along the support surface for substantially the height of the body. The shape adaptive members may be attached within the recess by way of an adhesive or the like.

In one embodiment, the shape adaptive members are positioned generally to 25 receive the vertebral column of the user and to adapt to the shape of the region of the user's back, adjacent the vertebral column. Such an arrangement may optimise the weight and pressure distribution between adjacent vertebrae of the vertebral column.

The shape adaptive members may be separated by a gap having a distance of 30 between 25-75 mm. The gap may be recessed from the surface of the shape adaptive members defining an open space between the shape adaptive members. Each shape adaptive member may have a width of between 25-75 mm. The body may be formed with a pair of recesses provided therein for receiving the shape adaptive members, The shape adaptive members may be attached within the recesses by way of an adhesive or 35 the like.

Received at IPONZ 15 March 2011 4 The shape adaptive members are positioned to receive the region of the user's back proximal the transverse processes of the vertical column, such that the spinous process may extend into the gap provided between the shape adaptive members. The shape adaptive members may adapt to the shape of the region of the user's back, 5 adjacent the transverse processes of the vertebral column, to optimises the weight and pressure distribution between adjacent vertebrae of the vertebral column.

In one embodiment, one or more of the shape adaptive members may be attached to the body such that they are substantially flush with the support surface of the body. In yet another embodiment, the shape adaptive members may be attached to the body such that they at least partially project beyond the support surface of the body.

In a second aspect, the present invention is a chair comprising: a base; a seat supported on said base; and a back support attachable to said base and extending substantially vertically therefrom, said back support being a back support according to the first aspect.

Brief Description of the Drawings By way of example only, the invention is now described with reference to the accompanying drawings; Fig. 1 is a perspective view of a chair useful for understanding the present invention; Fig, 2 is a front view of a chair incorporating an embodiment of the present invention; Fig. 3 is a top cross sectional view of the back support of the chair of Fig. 1; and Fig. 4 is a top cross-sectional view of the back support of the chair of Fig. 2.

Received at IPONZ 15 March 2011 Detailed Description of an Exemplary Embodiment of the Present Invention A chair, incorporating a back support, is generally shown in the accompanying 5 drawings as 10. Whilst the present invention will be described in relation to a standard office chair 10, it will be appreciated by those skilled in the art that the shape and type of the chair 10 could be any desired shape and type as desired.

As shown in Figs. 1 and 2, the chair 10 generally comprises a base 12, a seat 10 portion 14, arm rests 16 and a back support 18. The chair 10 is provided to accommodate a user in a sitting position with their posterior supported on the seat portion 14 such that the user's feet are able to be positioned on the ground which supports the base 12 of the chair 10.

Whilst the base portion 12 has been shown as incorporating wheels or castors 11 to enable the chair to be movable across a support surface, it will be appreciated that the chair 10 could incorporate standard legs having stopper elements or the like provided thereon, to prevent movement/slippage of the chair 10 across the support surface. Similarly, whilst arm rests 16 are shown, it will be appreciated that the present 20 invention could be equally applied to a chair 10 without arm rests 16.

The seat portion 14 comprises a cushion which receives the posterior of the user and provides comfort and support to the user to maintain a substantially upright seating posture. The seat portion 14 can be configured in a number of ways and may be 25 adjustable such that it can slope forward to ensure that the user is positioned with a straight back, and can be raised and lowered, by way of a handle 15 (Fig. 2), to accommodate users of variable heights and sizes.

As described in the Applicant's Registered Australian Patent 747131, which is 30 incorporated herein by reference, the seat portion 14 may have more than one cushion provided thereon. In this regard, a forward and a rearward cushion may be provided, with the rearward cushion having a higher resistance to resilient deformation than the forward cushion, or vice versa, to provide the desired amount and type of back alignment, Received at IPONZ 15 March 2011 6 The cushion(s) of the seat portion 14 may be made from a foam material, in the form of cut or moulded foam. The foam material can be a rubber latex foam and/or a polyurethane foam comprising a network of cellular shapes, thereby increasing the resilient flexibility of the seat portion 14. Similarly, the cushion(s) of the seat portion 5 14 may be layered with a variety of materials, such as foams and/or gel material to provide the desired support to the pelvis of the user and to ensure that the user is positioned upon the chair in a comfortable manner which ensures correct posture.

The back support 18 of the chair 10 extends upwardly from the rearward edge of 10 the seat portion 14, as is shown in Figs. 1 and 2. The back support 18 may be adjustable in both a vertical and lateral direction in accordance with the needs of the individual user.

The back support 18 forms a flat or contoured support surface 20 which is 15 provided to gently cradle the back of the user seated in the chair 10. In this regard, the back support 18 comprises a frame portion 22, in the form of a rear shell or internal skeleton which provides the general shape/structure of the back support 18. Provided within and/or about the frame portion 22 is a foam material 24, shown more clearly in Figs. 3 and 4.

The foam material 24 forms the majority of the support surface 20 of the back support 18 and may be a rubber latex foam or a polyurethane foam which is cut or moulded to form the desired surface contour. Typically this contour is slightly concave such that the surface 20 is able to gently cradle the back of the user. The foam material 25 24 is flexible to provide comfort to the user and may have a variable density and firmness depending upon the desired requirements of the user. A cover 21 in the form of a fabric covering may be provided to surround the foam material 24 before being mounted to the fame portion 22.

The foam material 24 may be Dunlop Enduro® - EN36-100 or Dunlop Enduro® - EN36-130 which has a resistance to resilient deformation of about 80 - 95 Newtons, However other types of foams are also envisaged to be used in concert with the present invention.

As shown in Figs. 1 and 2, a shape adaptive member in the form of a spinal support 25 is provided to receive and support the vertebral column of the user seated in Received at IPONZ 15 March 2011 7 the chair 10. The spinal support 25 extends substantially the height of the back support 18 in a central region which corresponds to the vertebral column of the user when seated in the chair. Whilst the spinal support 25 is shown as extending the entire height of the back support 18, it will be appreciated that the support 25 could extend along 5 only a portion of the height of the back support 18 as necessary to provide sufficient support to the vertebral column of the user.

As shown in Figs 1 and 3, in one form the spinal support 25 is a shape adaptive flexible pouch 30 provided in a single strip that extends along the central region of the 10 back support 18. The flexible pouch 30 contains a gel material within a suitable protective layer which forms a relatively soft and conformable surface for receiving and supporting the spine of the user. The gel material may be a hydrogel or a polymer gel, such as a viscoelastic polyurethane gel. Such a gel is sold under the trademark "ISOGEL" by Pittsburgh Plastics Manufacturing, Inc. of Zelienople, PA, United States 15 of America. The protective outer layer can comprise a polyurethane film material.

As shown in Fig. 3, the pouch 30 is positioned atop the foam material 24 and has a width of between 50 - 100 mm. In this regard, the foam material is moulded to define a space for receiving the pouch 30 which is secured within the space by way of 20 an adhesive material or the like. In this arrangement, the outer surface of the pouch 30 is substantially flush with the surface 30 of the back support 18 to define a surface that is capable of readily adapting to the shape of the person's spine, thereby adjusting to the ongoing needs of the spine and providing optimal weight and pressure distribution from the spine against the back support 18 of the chair 10. In this regard, the pouch 30 25 simulates body fat tissue and cradles the back to minimise lordosis of the spine.

As is appreciated, the vertebral column of an individual is composed of a series of thirty-one separate bones known as vertebrae 35. There are seven cervical or neck vertebrae, twelve thoracic vertebrae, and five lumbar vertebrae. Each vertebrae 35, as 30 represented diagrammatically in Figs. 3 and 4, comprises an anterior body 36 and a posterior arch 37. The arch 37 encloses an opening 38 which forms a canal in which the spinal cord is housed. The arch 37 comprises three bony elements, namely the spinous process 39 which extends from the posterior of the arch 37, and a pair of transverse processes 40 which extend laterally from the arch 37. These bony elements 35 serve as important sites of attachment of deep back muscles and also serve as important protective means for protecting the spinal cord.

Received at IPONZ 15 March 2011 8 Whilst not shown, adjacent vertebrae in the vertebral column are connected by specialised cartilaginous joints known as invertebral discs. Each disc is composed of a central core of gelatinous material and a surrounding series of fibrous rings. Body 5 weight of an individual is transmitted through the disc by loading the gelatinous material, which then compresses and transfers its loading to the fibrous rings of the disc. In most individuals, the fibres of the fibrous discs resist this load, but in some instances they may not, resulting in the gelatinous material being forced out of the disc, and the disc becoming herniated/ruptured, which can have a profound effect on the 10 adjacent spinal nerve.

In this regard, by providing a pouch 30 of gel material in the region of the back support 18 of the chair 10 that receives the vertebral column such that the spinous process 39 and the transverse processes 40 are accommodated, the chair 10 is able to 15 better assist in distributing the weight and pressure experienced between the vertebrae 35.

Figs. 2 and 4, show an embodiment of the shape adaptive members 25 of the present invention. In this embodiment, the shape adaptive member/spinal support 25 is 20 also shown as extending the height of the back support 18 of the chair 10, however it will be appreciated that the spinal support 25 could extend only a portion of the height of the back support 18 as required.

In this embodiment, a pair of shape adaptive members or pouches 32 are 25 provided in the form of strips which extend centrally along the back support 18 of the chair 10 atop the foam material 24. The foam material 24 is moulded/shaped to receive the pouches 32 in the manner as shown in Fig. 4. The pouches 32 are made from the same materials as the pouch 30 discussed above, and provide malleable surfaces which are able to conform to the back of the user in the manner as discussed above.

Each of the pouches 32 are separated by a distance of between 25-75mm and have a width of between 25-75mm. The foam material 24 provided in the gap between the pouches 32 is recessed from the outer surface of the pouches 32 to provide a recess 33.

Received at IPONZ 15 March 2011 9 As shown in Fig. 4, in such an arrangement, the pouches 32 act to support the transverse processes 40 such that the spinous process 39 is received within the recess 33. This arrangement provides maximum weight/pressure distribution between the vertebrae if the vertebral column providing additional comfort and support to the user.

It will be appreciated that by providing a chair 10 having such a spinal support 25 formed therein increases spinal stability of the user of the chair. Such a chair 10 is particularly useful for users suffering from back related problems, such as ruptured or herniated discs and ensures that weight is evenly distributed against the chair, It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as 15 illustrative and not restrictive.

Received at IPONZ 15 March 2011

Claims

CLAIMS:

1. A back support for a chair, the back support comprising: 5 a substantially vertical foam body having a support surface for receiving a back of a user when said user is in a seated position on said chair, the foam body having at least one elongate recess formed in the support surface, the at least one elongate recess extending in a substantially vertical direction at a central region of the support surface; and 10 at least two shape adaptive members separated by a gap, each shape adaptive member being a generally elongate strip located at least partially in the at least one elongate recess; wherein the shape of each shape adaptive member is variable in response to pressure applied thereto by the back of said user when said user is in said seated 15 position; and wherein, when the user is in said seated position, each shape adaptive members is adapted to support a region of the user's back proximal the transverse processes of the user's vertebral column and the gap is adapted to receive a region of the user's back proximal the spinous processes of the user's vertebral column. 20

2. A back support according to claim 1, wherein the support surface is a substantially flat surface.

3. A back support according to claim 1, wherein the support surface is contoured to conform to the user's back. 25

4. A back support member according to claim 1, 2 or 3 wherein each shape adaptive member comprises a pouch containing a quantity of gel material.

5. A back support member according to claim 4, wherein the gel material is a 30 hydrogel or a polymer gel.

6. A back support member according to claim 5, wherein the gel material is a viscoelastic polyurethane gel. Received at IPONZ 15 March 2011 11

7. A back support member according to claim 4, 5 or 6, wherein the pouch is constructed from a polyurethane film material which assumes the shape of the gel material contained therein. 5

8. A back support member according to claim 7, wherein the shape of the pouch changes in response to pressure applied thereto by the back of the user, which causes a change in the distribution of the gel within the pouch.

9. A back support member according to any one of the preceding claims, wherein 10 the shape adaptive members extend along the support surface for substantially the height of the body.

10. A back support member according to any one of the preceding claims, wherein the shape adaptive members are attachable within the one or more recesses by way of 15 an adhesive,

11. A back support member according to any one of the preceding claims, wherein each shape adaptive member has a width of between 25-75 mm. 20

12. A back support member according to any one of the preceding claims, wherein the shape adaptive members are positioned in the at least one recess in the support surface of the body such that they are substantially flush with the support surface of the body. 25

13. A back support member according to any one of claims 1 to 12, wherein the shape adaptive members are positioned in the at least one recess in the support surface of the body such that they at least partially project beyond the support surface of the body. 30

14. A chair comprising: a base; a seat supported on said base; and a back support attachable to said base and extending substantially vertically therefrom, said back support being a back support according to any one of the 35 preceding claims.