GB2140294A

GB2140294A - Inflatable lumbar support cushion

Info

Publication number: GB2140294A
Application number: GB08314445A
Authority: GB
Inventors: Robert Leslie Easter
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1983-05-25
Filing date: 1983-05-25
Publication date: 1984-11-28
Also published as: GB8314445D0; GB2140294B; DE3417972C2; DE3417972A1

Abstract

An inflatable lumbar support cushion has an inflatable region of generally oval shape with sides 26 and ends 24 surrounding a non-inflatable region 18. The ends 24 may be fatter then the sides 26 to provide side support when the cushion is inflated. The region 18 can be of a dog-bone shaped, and the cushion can be made of two sheets of rubber bonded together. <IMAGE>

Description

SPECIFICATION Inflatable lumbar support cushion This invention relates to an inflatable lumbar support cushion which may be used in a seat to provide an adjustable degree of support for the lumbar region of the back. The invention also relates to a seat including such a cushion.

According to the present invention, there is provided an inflatable lumbar support cushion which has an inflatable chamber surrounding an area which is not inflatable.

The area which is not inflatable is preferably of a "dog bone" shape, and will normally have an area substantially smaller than that of the inflatable chamber. The chamber may be generally oval with the ends of the oval, when inflated, fatter than the sides. The cushion may be made of two sheets of rubber selectively bonded together.

The invention also provides a motor vehicle seat with a cushion as set forth above in the seat backrest, and means, accessible to an occupant of the seat, for inflating the cushion.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a cushion in accordance with the invention, Figures 2 and 3 are sections through the cushion of Fig. 1, when inflated, the setions being taken on the lines ll-ll and 111-Ill in Fig. 1, and Figure 4 is a detail of the valve shown in circle A of Fig. 1.

The cushion 10 in the drawings is made from two rectangular sheets 12, 14 of rubber.

The sheets are bonded together around their periphery 1 6 and in a central area 18, so that a single inflatable chamber 20 is defined.

The central bonded area 18 has a dog-bone shape, and the inflatable chamber 20 is generally oval, its ends 24, when inflated, being of greater cross-sectional area, or fatter, than its sides. This can be seen in particular in Fig. 2. The presence of the central bonded area means that full inflation can be achieved with less air than would be the case without this area. The cushion can therefore be pumped up or deflated quickly. Also, suitable dimensioning of the bonded areas 1 6 and 18 ensures that the enlarged ends 24 are obtained. This provides a desirable degree of side support for a seat occupant. The spacing apart of the sides 26 of the chamber 20 provides lumbar support over a relatively large area.

The cushion which can suitably be made of rubber will be included in the backrest of a motor vehicle seat, normally in front of a wire mat secured to the seat frame and behind the seat upholstery. The cushion has securing holes 28 which are used to hold the cushion in the correct place in the seat.

To inflate the cushion, a flexible bulb 28 is provided on the end of a tube 30 remote from the cushion. The tube 30 includes an inner tube 32. When the bulb 28 is squeezed, inflation air passes down the tube 30, around the inner tube 32, through a valve 34 and into the cushion chamber 20. To deflate the cushion, a button 36 on the top of the bulb is pressed. This opens a valve 38 which allows air to flow from the cushion chamber 20 through the inner tube 32 to atmosphere.

An arrangement of this type is shown in our Patent Application No. 8236073. The valve 34 may be positioned adjacent the bulb, as described there, or adjacent the cushion as described here.

In a motor vehicle, the bulb 28 may be mounted in a position which is accessible at one side of the seat, so that the seat occupant can easily reach it to pump up the cushion or, by pressing the button 36, to deflate the cushion.

The valve 34 is shown in detail in Fig. 3. It has an outer sleeve 40 fitted at the end of the tube 30. The inner tube 32 extends through the sleeve, and the inlet to the chamber 20 is sealed around the upper (as seen in Fig. 3) part of the sleeve by a ring 33 (Fig. 1).

A rubber valve member 42 is held in the sleeve by a support 44. In the rest position shown, the valve member blocks the air passage between the sleeve and the inner tube.

On applying pressure in the direction of the arrow 46, the rubber valve member will lift from the tube 32 and allow air into the cushion. When the pressure in this direction drops, the valve member will return to the position shown and the pressure inside the cushion will keep the valve closed.

To refill the bulb with air before another squeeze or pressure stroke, air inlets 48 are provided. On the pressure stroke, these are sealed by a skirt 50 of the valve member 42.

On the suction stroke, when the resilience of the bulb draws air back into the tube 30, the skirt lifts to admit air through the inlets 48 and through a filter 52. When the bulb is again squeezed to deliver a pressure stroke, the skirt is sealed back against the sleeve wall.

1. An inflatable lumbar support cushion which has an inflatable chamber surrounding an area which is not inflatable.

2. A cushion as claimed in Claim 1, wherein the area which is not inflatable is of a dog-bone shape.

3. A cushion as claimed in Claim 1 or Claim 2, wherein the chamber is generally oval.

4. A cushion as claimed in Claim 2, wherein the ends of the oval are, when inflated, fatter than the sides.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Inflatable lumbar support cushion This invention relates to an inflatable lumbar support cushion which may be used in a seat to provide an adjustable degree of support for the lumbar region of the back. The invention also relates to a seat including such a cushion. According to the present invention, there is provided an inflatable lumbar support cushion which has an inflatable chamber surrounding an area which is not inflatable. The area which is not inflatable is preferably of a "dog bone" shape, and will normally have an area substantially smaller than that of the inflatable chamber. The chamber may be generally oval with the ends of the oval, when inflated, fatter than the sides. The cushion may be made of two sheets of rubber selectively bonded together. The invention also provides a motor vehicle seat with a cushion as set forth above in the seat backrest, and means, accessible to an occupant of the seat, for inflating the cushion. The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a cushion in accordance with the invention, Figures 2 and 3 are sections through the cushion of Fig. 1, when inflated, the setions being taken on the lines ll-ll and 111-Ill in Fig. 1, and Figure 4 is a detail of the valve shown in circle A of Fig. 1. The cushion 10 in the drawings is made from two rectangular sheets 12, 14 of rubber. The sheets are bonded together around their periphery 1 6 and in a central area 18, so that a single inflatable chamber 20 is defined. The central bonded area 18 has a dog-bone shape, and the inflatable chamber 20 is generally oval, its ends 24, when inflated, being of greater cross-sectional area, or fatter, than its sides. This can be seen in particular in Fig. 2. The presence of the central bonded area means that full inflation can be achieved with less air than would be the case without this area. The cushion can therefore be pumped up or deflated quickly. Also, suitable dimensioning of the bonded areas 1 6 and 18 ensures that the enlarged ends 24 are obtained. This provides a desirable degree of side support for a seat occupant. The spacing apart of the sides 26 of the chamber 20 provides lumbar support over a relatively large area. The cushion which can suitably be made of rubber will be included in the backrest of a motor vehicle seat, normally in front of a wire mat secured to the seat frame and behind the seat upholstery. The cushion has securing holes 28 which are used to hold the cushion in the correct place in the seat. To inflate the cushion, a flexible bulb 28 is provided on the end of a tube 30 remote from the cushion. The tube 30 includes an inner tube 32. When the bulb 28 is squeezed, inflation air passes down the tube 30, around the inner tube 32, through a valve 34 and into the cushion chamber 20. To deflate the cushion, a button 36 on the top of the bulb is pressed. This opens a valve 38 which allows air to flow from the cushion chamber 20 through the inner tube 32 to atmosphere. An arrangement of this type is shown in our Patent Application No. 8236073. The valve 34 may be positioned adjacent the bulb, as described there, or adjacent the cushion as described here. In a motor vehicle, the bulb 28 may be mounted in a position which is accessible at one side of the seat, so that the seat occupant can easily reach it to pump up the cushion or, by pressing the button 36, to deflate the cushion. The valve 34 is shown in detail in Fig. 3. It has an outer sleeve 40 fitted at the end of the tube 30. The inner tube 32 extends through the sleeve, and the inlet to the chamber 20 is sealed around the upper (as seen in Fig. 3) part of the sleeve by a ring 33 (Fig. 1). A rubber valve member 42 is held in the sleeve by a support 44. In the rest position shown, the valve member blocks the air passage between the sleeve and the inner tube. On applying pressure in the direction of the arrow 46, the rubber valve member will lift from the tube 32 and allow air into the cushion. When the pressure in this direction drops, the valve member will return to the position shown and the pressure inside the cushion will keep the valve closed. To refill the bulb with air before another squeeze or pressure stroke, air inlets 48 are provided. On the pressure stroke, these are sealed by a skirt 50 of the valve member 42. On the suction stroke, when the resilience of the bulb draws air back into the tube 30, the skirt lifts to admit air through the inlets 48 and through a filter 52. When the bulb is again squeezed to deliver a pressure stroke, the skirt is sealed back against the sleeve wall. CLAIMS

5. A cushion as claimed in any preceding claim and made of two sheets of material selectively bonded together.

6. A cushion as claimed in Claim 5, wherein the material is rubber.

7. An inflatable lumbar support cushion substantially as herein described with reference to the accompanying drawings.

8. A motor vehicle seat with a cushion as claimed in any preceding claim in the seat backrest and means, accessible to an occupant of the seat, for inflating the cushion.