Chair with inflatable cellular insert

Abstract

A chair having a backrest and seat with a seat cushion including a base with an inflatable air cell pad positioned securely within the base so as to be positioned under the areas of high-pressure areas on the buttocks of a normally positioned user. The inflatable air cell pad is operatively connected to a pump device having an external control on the chair for access by a seated user of the chair. The user can sit on the chair seat and inflate or deflate the air cell pad for optimal support and comfort. In one aspect of the chair the pump is an electric pump. In one aspect of the chair, the backrest also comprises a base with an inflatable air cell pad.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No. 10/896,572, filed Jul. 22, 2004, which claims the benefit of provisional patent application Ser. No. 60/489,041, filed Jul. 22, 2003, both of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The invention relates generally to furniture and more specifically to a chair cushion that provides improved pressure distribution and reduced pressure at high pressure points.

Sitting on a chair for long periods of time can result in discomfort in the buttocks, particularly at high pressure points such as the ischia and bony prominences. It also can cause discomfort in the back, for example, the spine, shoulders and shoulder blades. Although a number of chairs are available having padding or the like, it would be beneficial to provide a chair that includes a seat cushion that provides improved pressure distribution and reduced pressure at high pressure points, and even more beneficial if the user can easily and conveniently adjust the pressure distribution and reduction aspects of the cushion. Furthermore, it would be advantageous to provide a chair, particularly a lounge chair or recliner, that provides improved pressure distribution under the back, arms and legs.

SUMMARY OF THE INVENTION

One aspect of the invention provides a chair having seat including a contoured, padded base with an inflatable air cell pad positioned securely within the base and encased within a cover. The air cell pad is optimally located in the base so as to be positioned under the user's buttocks, particularly under the high-pressure areas of the buttocks of a normally positioned user. The inflatable air cell pad is operatively connected to a pump device located outside the cover for access by the user of the chair. The user can sit on the cushion and then inflate or deflate the air cell pad for optimal support and comfort. The pump can be of any acceptable design. In one aspect of the invention the pump comprises a bulb and valve combination.

In another aspect of the invention, the seat cushion is employed in an easy chair, lounge chair or recliner. The inflatable air cell pad cushion is operatively connected to a pump such as the one described. Alternatively, in another aspect of the invention, the inflatable air cell pad can be connected to an automatic pump, such as a small electric pump. The pump is operatively connected to a controller. The seated user can actuate the controller to set the inflation level of a desired level for optimal support and comfort.

In yet another aspect of the invention, the base with an air cell pad is positioned in the back rest of the chair and can be operatively connected to a manual or automatic pump and controller.

In another aspect of the invention the base comprises a substantially rigid frame with the air cell pad positioned within the frame. The base and air cell pad are enclosed within the chair seat or backrest or both.

In another aspect of the invention, the chair has pressure-distributing pads under high-pressure areas, including the seat, the backrest, head and/or neck rest, the armrests and a leg rest.

Moreover, in another aspect of the invention, the pressure-distributing pads comprise a pad selected from a group of pressure-distributing pads consisting of air cell pads, inflatable pillows or gel-type pads.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or patent application contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawings will be provided by the Office upon request and payment of the necessary fee.

FIG. 1 is a perspective view of a representative embodiment of an office chair including a seat cushion of the present invention with the seat cover partial cut away to expose the air cell insert;

FIG. 2 is a perspective view of the seat cushion of the present invention, sans cover;

FIG. 3 is a cross sectional view of the cushion of the present invention taken along line 3-3 of FIG. 2;

FIG. 4 is a side elevational view of the cushion of the present invention;

FIG. 5 is a perspective view of the air cell pad;

FIG. 6 is a cross section view of the cushion of the present invention, similar to FIG. 3, wherein the air cell pad is inserted in a cavity formed in the top of the resilient base;

FIG. 7 is a front plan view of a representative embodiment of recliner chair including a back rest cushion and a seat cushion of the present invention with the covering partial cut away to expose the air cell inserts;

FIG. 8 is a side elevational view of a representative embodiment of recliner chair in a reclining position;

FIG. 9 is a perspective view of a representative embodiment of a side chair including a back rest cushion and a seat cushion of the present invention with the covering partial cut away to expose the air cell inserts;

FIG. 10 is a side elevational view of another representative embodiment of a recliner chair in a reclining position;

FIG. 11 is a pressure map of a prior art office chair seat cushion showing areas of distribution of 50 mm Hg pressure;

FIG. 12 is a pressure map of a seat cushion of the present invention showing areas of distribution of 50 mm Hg pressure;

FIG. 13 is a pressure map of a prior art office chair seat cushion showing areas of distribution of 40 mm Hg pressure;

FIG. 14 is a pressure map of a seat cushion of the present invention showing areas of distribution of 40 mm Hg pressure;

FIG. 15 is a pressure map of a prior art office chair seat cushion showing areas of distribution of 30 mm Hg pressure; and

FIG. 16 is a pressure map of a seat cushion of the present invention showing areas of distribution of 30 mm Hg pressure.

DETAILED DESCRIPTION OF ONE EMBODIMENT OF THE INVENTION

A chair, employing a seat cushion of the present invention is indicated generally in FIG. 1 by reference numeral 20. Chair 20, in the embodiment of FIG. 1, is configured like a conventional office chair. However chair 20 can be of any acceptable configuration and, at a minimum includes a seat cushion 21. Chair 20 also includes a backrest 23. Chair 20, as shown, includes a floor engaging base 25 having casters 27 and an upwardly extending pedestal 29 connected to a pan 30 (FIG. 3) on which the seat cushion is mounted. Pedestal 29 generally is connected to pan 30 by a swivel connection (not shown).

Backrest 23 includes a structural frame (not shown) and is attached to the seat pan by an appropriate brace 31 or the like. In most embodiments, base 25, casters 27, pedestal 29, pan 30, brace 31 and the backrest frame are constructed of metal. Hence, the backrest is padded for comfort, as is the seat cushion, as will be explained below, and both are enclosed by an acceptable cover 33. Cover 33 usually is a durable, aesthetically pleasing fabric. In the present invention, certain physical qualities are preferred, particularly the cover of seat cushion 21.

It will be appreciated that chair 20 as shown is a basic configuration for simplicity of description, and the acceptable configurations of a chair employing the seat cushion of the present invention are unlimited. The chair can have a headrest, arm rests, legs, and so forth. The claimed seat cushion can be used in any seating environment. It can be particularly suited to those users who are seated for extended periods of time, such as chairs in theatres, dentists' chair, chairs in hair salons, barber chairs, and chairs for home use, similar to those described below.

Seat cushion 21, without a cover, is shown in greater detail in FIGS. 2 through 4 and 6. Cushion 21 includes a supportive, resilient base 35. Base 35, in an illustrated aspect of the invention, is comprised of polyurethane foam and shaped with appropriate contours to facilitate comfortable seating by the user, as known in the art. Base 35 includes a cut out area or cavity 37 and an air cell pad 39 positioned in cavity 37. In general, cavity 37 is formed in the bottom of base 35 and air cell pad 39 is introduced into the cavity and a foam layer or seal can be secured to the bottom of the base to keep air cell pad 39 in place. In one aspect of the invention the thickness of the foam can range for ½ in to more than 3 inches, preferably 1½ inches to 2 inches or more. It will be appreciated that foam other than polyurethane foam can be employed, including, but not limited to viscoelastic foam or any other type of material that imparts the functional qualities of a foam.

In alternative embodiments of the invention, for example, as shown in FIG. 6, cavity 37 can be formed in the top of base 35 with air cell pad 39 introduced from the top. In such an arrangement, there can be a thin layer of foam 38 positioned over the air or, the air cell pad can be covered only by cover 33. In yet another alternative embodiment, the cover can have an opening at the air cell pad, so that the air cell pad is exposed.

Air cell pad 39 is located in base 35 at a position that places the air cell pad under the ischial area of a normally seated user. The ischial tuberosities are the lower portions of the hip bones and usually represent the area of greatest pressure on the buttocks of a seated user. Most discomfort experienced from prolonged seating is felt in the buttocks at the ischial area.

In any event, air cell pad 39, shown in detail in FIG. 5, is comprised of a flexible base 40 and an array of individual air cells 42 arranged in rows of air cells across the base. In the illustrated embodiment, each air cell 42 is preferably an expandable, four fin cell preferably molded from neoprene. Any geometry of cell can be employed however, such as pyramidal shaped, cells having more than four fins, cubes or other useful shapes.

The geometry of the air cells, however, should provide minimal resistance to conformity to the shape of the buttocks of the seated user. In a preferred aspect of the invention, the air cells are approximately 2 inches in height. As seen in FIG. 3, the geometry of the air cells 42 in array of air cells provides for a smooth transition between the air cell pad 39 and surrounding base 35. The individual air cells 42 are interconnected so that air introduced into one cell is distributed among the cells so as to equalize pressure within the cells.

As shown in FIG. 5, there is an air conduit 46 connected to one air cell 42 at one end and a pump, shown as bulb pump 48 in FIG. 4, at the other end. Air cell pad 39 preferably can be molded from neoprene in accordance with the teachings of U.S. Pat. No. 4,541,136, which is incorporated herein by reference. Air cell pad 39 also can be made from urethane or PVC or other plastic or moldable materials that can be used to make an air cell.

Base 35 is enclosed in cover 33. In the illustrated embodiment, the top surface of cover 33 should stretch to deform under the seated user, ideally 250% by 170%. It is not necessary for the cover material over the sides of the seat cushion to stretch. The cover material at the top surface preferably also should be breathable. In the illustrated embodiment, the cover also encloses air cell pad 39.

It will be appreciated from the drawings that in the illustrated embodiment, bulb pump 48 is located on one side of seat cushion 21, outside cover 33 so as to be accessible to the user seated on the chair. The pump can be located in any convenient place on the chair as long as it is easily accessible by a seated user and is in fluid communication with air cell pad 39. The pump actually could be under the cover, as shown in FIG. 4, yet accessible for actuation by depressing the cover and bulb, for example. Pump 48 includes a bulb 50 and push button relief of valve 52. The user can actuate bulb 50 and pump air into the air cell pad and depress push button valve 52 to allow the release of air from the air cell pad. Although the illustrated embodiment employs a bulb pump, it is intended that any acceptable pump be encompassed by the present invention.

To achieve optimal benefit of the seat cushion of the present invention, the user sits on the cushion with the ischial area positioned over air cell pad 39. The user then can actuate pump bulb 50 and pump air into the air cell pad until that individual user is comfortable and well supported. The cells 42 deform under the buttocks and thighs to provide a maximum Air Floatation® support surface. The user also can allow air to escape through the valve until he or she reaches a desired immersion into air cell pad 39 to provide customized support surface. This support surface provides superior pressure relief over prior art seat cushions, as shown by pressure mapping illustrated in FIGS. 11 through 16, below. In any event, during use, if the user wants to change the immersion depth or seating characteristics, he or she can open the valve and adjust the air pressure within air cell pad 39.

FIGS. 7 and 8 illustrate another embodiment of a chair, indicated generally by reference numeral 60 incorporating the seat cushion of the present invention. As shown, chair 60 has a conventional external appearance, in this instance, including a seat 62 for supporting seated user, a backrest 64, a left armrest 66 and a right armrest 68. As best seen in FIG. 8, chair 60 can be configured as a lounge chair or reclining chair, commonly referred to as a recliner. In this configuration, chair 60 includes a conventional reclining mechanism 70 that operates to allow backrest 64 to lay back and a leg rest 72 to elevate. When chair 60 is fully reclined, the user is positioned in a nearly horizontal position. Of course, the backrest and leg rest can be positioned as desired so that the user can sit in any number of positions from fully upright (FIG.7) to fully reclined.

In any event, chair 60 includes a seat cushion of the present invention indicated generally by reference numeral 74 in FIG. 8. Seat cushion 74 is enclosed in seat 62. Seat cushion 74 includes a resilient foam base 76 and an inflatable air cell pad 78. Base 76 and air cell pad 78 are constructed according to the principles set out above. It will be appreciated in a chair of the style of chair 60, that seat 62 may be of the conventional type with a frame, such as a wooden frame with padding, with springs or the like positioned under the padding. Hence, a cavity is formed in the padding, with base 76 and air cell pad 78 positioned in the cavity. Alternatively, seat cushion 74 can be installed inside the seat frame and replace any other padding.

Alternatively, air cell pad 78 can be employed directly in a seat, without base 76, as will be explained below in reference to FIG. 9. In either embodiment, additional padding can be placed over the air cell pad, or just a thin layer of padding or foam placed over the air cell pad, and the entire seat 62 is covered with upholstery, leather, vinyl or other appropriate cover material. It will be noted that the cover over air cell pad 78 can be fashioned from the stretchy material described above.

As seen in FIG. 8, air cell cushion 78 is connected to a pump 82 by air conduit 84. Although a hand actuated pump similar to the one described above can be used, in the illustrated embodiment, pump 82 is a small electric pump housed inside the bottom of the chair itself. Pump 82 has a cord 86 for plugging into an electric outlet. Pump 82 also is operatively connected to a control, indicated generally by control 88. Control 88 is positioned on the exterior of the chair so as to be accessible by a seated user. Control 88 is used to actuate pump 82 so as to inflate air cell pad 78 to taste. Control 88 also can be provided with an indexing mechanism so that the user can set control 88 to an indicia or number, for example, that correspondence to a particular inflation pressure or firmness.

Chair 60 also includes an air cell pad 90 in backrest 64. Air cell pad 90 is positioned within a base 92, which can be a resilient foam base of the type described above or, alternatively, it can be a base comprising a substantially rigid frame with underlying support structure such as springs, as will be described below. There can be padding surrounding the base and air pad combination or the base and air cell pad can comprise the entire backrest. There can be a layer of padding on top of the air cell pad or a thin layer of foam or nothing at all. Backrest 64 is enclosed in an appropriate cover material, including stretchy fabric over the air cell pad, if desired. In the illustrated embodiment, air cell pad 90 is in fluid communication with pump 82 by air conduit 94. As with the air cell pad 78, control 88 can be used to select a firmness of air cell pad 90.

FIG. 9 illustrates a side chair 100 including seat 102, a backrest 104, and armrests 105. There is an air cell pad 106 in a base 108 within seat 102 and an air cell pad 110 in a base 112 within back rest 104. In this embodiment, each base comprises a substantially rigid frame positioned around the air cell pad to keep the air cell pads in position and the underlying springs or other support structure. In essence, in this embodiment the frame and the underlying support structure function as a non-resilient base and the air cell pads 106 and 110 are positioned in the base. These types of base and air cell pad combinations can be employed in any configuration of a chair, such as chair 20 or chair 60 and are shown only in chair 100 for purposes of brevity and clarity.

FIG. 10 illustrates yet another embodiment of the reclining chair 60 of FIGS. 7 and 8. In this embodiment, chair 60 includes an air cell pad 120 in the arm rests 66 and 68 to provide enhanced support and comfort to the resting arms of a user. Moreover, there is an air cell pad 122 in leg rest 72 to provide enhanced support and comfort for the lower leg, for example the calves, of the seated user. There also can be an air cell cushion in a head and/or neck rest.

In any event the respective air cell pads, regardless of the location in the various chairs can be pre-inflated at the time of assembly or can be connected to a bulb type pump, or to an electric pump and controller of the types previously described, for inflation. The fact that the supportive characteristics of the base and pressure distributing pad configurations of the present invention, whether employed in a chair seat or a chair backrest, armrests or leg rests, can be provided in chairs of unlimited styles and configurations to enhance the support and comfort of a seated user.

It will also be appreciated that in addition to the air cell pads described above, the chairs can be equipped with support or pressure distributing pads having similar support and pressure distributing characteristics, such as single bladder inflatable pads, inflatable pillows, or gel-type pads. Gel pads, for example, have good support and pressure distributing characteristics and can be used in place of the air cell pads to impart desired support and pressure distribution characteristics to a chair. Hence, a pressure distributing pad, in the present invention, can include the air cell pads described above, or any other type of inflatable or gel-type support that can impart support and pressure relief characteristics to the chair seats, backrests, armrests or leg rests or any other section of a chair.

The pressure maps in FIGS. 11 through 16 are a visual representation of the force distribution on a seat cushion of the present invention, particularly that cushion shown in FIG. 1-6, versus a prior art office chair seat cushion designed to reduce pressure. The prior art cushion tested is the Ergogenesis Model No. J2507 (Ergogenesis, Navasota, Tex.). The prior art seat cushion is a contoured seat, based upon the concept of zero gravity posture that is designed to disperse the user's body weight over an increased surface area.

In creating the pressure maps approximately 35 to 40 mm Hg pressure was applied to the cushion by a seated load. The darkest areas of the black and white pressure maps, which correspond to the red areas of the color pressure maps, represent the areas of greatest pressure. FIGS. 11 and 12 illustrate the areas of 50 mm Hg pressure resulting from the force load on the prior art seat cushion (FIG. 11) and the cushion of the present invention (FIG. 12). As shown by the pressure maps, areas of resulting 50 mm Hg pressure appear on the pressure map of FIG. 11, whereas none appear on pressure map of FIG. 12.

FIGS. 13 and 14 illustrate the distribution of 40 mm Hg pressure or greater in the respective cushions under the force load. As can be seen in FIG. 13, the pressure map of the prior art cushion illustrates a significant area of pressure of 40 mm Hg or greater, whereas the cushion of the present invention again shows none.

Finally, FIGS. 15 and 16 show the distribution of 30 mm Hg pressure or greater under the force load. The pressure map of the prior art cushion, FIG. 15, shows an even greater area of pressure when measuring pressure of 30 mm Hg or more, whereas the cushion of the present invention, mapped in FIG. 16, shows relatively small areas of pressure of 30 mm Hg or greater under the force load.

It will be appreciated by comparing the darkest areas of the pressure maps in the black and white pressure maps, which correspond to the red color in the color pressure maps, that the seat cushion of the present invention reduces pressure, particularly at the ischial areas when measuring three different pressure distributions under a constant force load.

It will be appreciated that the foregoing description and accompanying drawings illustrate one representative aspect of the invention, including the best mode of working the invention presently known to the inventor. However, the specification should be viewed as illustrative of the broadest aspects of the invention and should not be construed in a limiting sense.

Claims

1. A chair for support of a seated user, comprising:

a backrest to support the back of a normally positioned user;

a seat to provide support under a buttocks area of a normally positioned user;

the seat comprising: a base; an inflatable air cell pad positioned securely within the base and located in the base so as to be positioned under an area of high pressure on the buttocks of a normally positioned user; and

a pump device operatively connected to the air cell pad and positioned for access by the user of the chair so the user can sit on the seat and inflate or deflate the air cell pad with the pump device for optimal support and comfort.

2. The chair of claim 1 wherein the pump device is an electric pump.

3. The chair of claim 2 further comprising a control operatively connected to the electric pump wherein the user can inflate or deflate the air cell pad with the pump device for optimal support and comfort

4. The chair of claim 1 wherein the pump device comprises a bulb and valve combination.

5. The chair of claim 1 wherein the base comprises a cavity for placement of the air cell pad.

6. The chair of claim 1 further comprising a second inflatable air cell pad positioned in a base within the backrest.

7. The chair of claim 6 wherein the second inflatable air cell pad is operatively connected to the pump device.

8. The chair of claim 6 wherein the recited air cell pads comprise a flexible base, an array of individual interconnected air cells on the base, and an air conduit having one end in fluid connection with at least one of the individual air cells and a second end connectable to the pump.

9. The chair of claim 7 wherein the air cell pad is formed from neoprene.

10. The chair of claim 1 wherein the base is formed from polyurethane foam.

11. The chair of claim 1 wherein the base comprises a framework positioned within the seat to secure the inflatable air cell cushion in place

12. The chair of claim 1 wherein the air cell pad is formed from a plastic material.

13. A chair for support of a seated user, the chair comprising:

a backrest for supporting the back of a seated user, said backrest comprising a base and a first inflatable air cell pad positioned in a space defined by the base;

a seat cushion for support of a buttocks area of the seated user, said seat cushion further comprising: a base defining a space for an inflatable air cell pad; a second inflatable air cell pad positioned securely within the space defined by the base so as to be positioned under an area of high pressure on the buttocks area of a normally positioned user, a pump device operatively connected to the second air cell pad for access by the user of the chair so the user can sit on the seat and inflate or deflate the air cell pad with the pump device for optimal support and comfort; and a control for actuating the pump device.

14. The chair of claim 13 wherein the pump device is an electric pump.

15. The chair of claim 13 wherein the first air cell pad is operatively connected to the pump device.

16. The chair of claim 13 wherein each air cell pad comprises a flexible base, an array of upstanding, interconnected air cells on the base and, an air conduit in fluid communication with at least one of the individual air cells;

17. The chair of claim 13 wherein the base is a resilient foam base.

18. The chair of claim 17 wherein the space defined by the base is formed through a top surface of the base.

19. The chair of claim 17 wherein the space defined by the base is formed through a bottom surface of the base.

20. The chair of claim 13 wherein the base further comprises a substantially rigid frame defining the space for an air cell pad.

21. A chair for support of a seated user, the chair comprising:

a backrest for supporting the back of the seated user:

a first inflatable air cell pad positioned securely within said back rest, said air cell pad comprising a flexible base, an array of upstanding, interconnected air cells on the base and an air conduit in fluid communication with at least one of the individual air cells;

a seat for seating of the user, the seat comprising a base defining a space for a second inflatable air cell pad, which is positioned securely within the base and located in the base so as to be positioned under an area of high pressure on the buttocks of a normally positioned user, said second air cell pad comprising a flexible base, an array of upstanding, interconnected air cells on the base and an air conduit in fluid communication with at least one of the individual air cells; and

a pump operatively connected to the air conduit of the second air cell cushion and positioned for access by the seated user of the chair so the user can sit on the seat cushion and inflate or deflate the air cell pad with the pump for optimal support and comfort.

22. The chair of claim 21 wherein said pump is an electric pump.

23. The chair of claim 21 wherein said pump is operatively connector to a control wherein said control allows the user to select an inflation level of the seat air cell cushion.

24. The chair of claim 21 wherein the air conduit of said first air cell cushion is in fluid communication with the pump and wherein the control allows the user to select an inflation level of the back rest air cell cushion.

25. The chair of claim 21 wherein the base is a foam base having a cavity formed through a top surface of the foam base.

26. The chair of claim 21 wherein the base is a substantially rigid framework defining the space for the second air cell pad.

27. The chair of claim 21 further comprising a leg rest and a reclining mechanism.

28. A chair for support of a seated user, comprising:

a backrest to support the back of a normally positioned user;

a seat to provide support under a buttocks area of a normally positioned user;

the seat comprising: a base; and

a pressure distributing pad positioned securely within the base and located in the base so as to be positioned under an area of high pressure on the buttocks of a normally positioned user; said pressure distributing pad selected from a group of pressure distributing pads consisting of an air cell pad, an inflatable pillow, and a gel-type pad.

29. The chair of claim 28 further comprising a pressure distributing pad positioned within the backrest, said pressure distributing pad selected from a group of pressure distributing pads consisting of an air cell pad, an inflatable pillow, and a gel-type pad.

30. The chair of claim 28 further comprising leg rest having a pressure distributing pad positioned within the leg rest said pressure distributing pad selected from a group of pressure distributing pads consisting of an air cell pad, an inflatable pillow, and a gel-type pad.

31. The chair of claim 28 further comprising a first and second arm rest, each said arm rest having a pressure distributing pad positioned within the armrest said pressure distributing pad selected from a group of pressure distributing pads consisting of an air cell pad, an inflatable pillow, and a gel-type pad.