INFLATABLE SUPPORT APPLIANCE
First Claim
1. An inflatable support appliance having a surface for contact by a user, said surface comprising a flexible and extensible continuous material which is non-permeable to solids and liquids but is capable of transmitting water vapour from the outside of said surface to the inner side of said surface when the partial pressure of water vapour at the outer side of the surface exceeds that of the inner side of the surface, said appliance further having an inlet for air and an outlet for discharging the air and means for providing a constant flow of air under pressure to the inlet of the appliance both to support or partially support the user of the appliance and to remove water vapour transmitted to the interior of the appliance by said material to maintain a relatively low water vapour pressure within the appliance and thereby induce excess water vapour on the external side of said surface to pass through the surface to the inside of the appliance to be removed by said air flow.
2 Assignments
0 Petitions
Accused Products
Abstract
The specification discloses an air mattress consisting of a number of cells each having a surface which supports a user formed from a material which is gas permeable but is nonpermeable to liquids and solids. An air supply is provided for inflating the cells to the required pressure.
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Citations
18 Claims
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1. An inflatable support appliance having a surface for contact by a user, said surface comprising a flexible and extensible continuous material which is non-permeable to solids and liquids but is capable of transmitting water vapour from the outside of said surface to the inner side of said surface when the partial pressure of water vapour at the outer side of the surface exceeds that of the inner side of the surface, said appliance further having an inlet for air and an outlet for discharging the air and means for providing a constant flow of air under pressure to the inlet of the appliance both to support or partially support the user of the appliance and to remove water vapour transmitted to the interior of the appliance by said material to maintain a relatively low water vapour pressure within the appliance and thereby induce excess water vapour on the external side of said surface to pass through the surface to the inside of the appliance to be removed by said air flow.
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2. An inflatable support appliance as claimed in claim 1 comprising a base having an integral upstanding wall bounding a trough the bottom of which is formed with said inlet and an inverted trough shaped enclosure formed from said flexible and extensible continuous material secured around its lower periphery to the periphery of the wall.
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3. An inflatable support appliance as claimed in claim 1 wherein the base has a plurality of said upstanding walls defining a set of side by side troughs and each trough has an inverted trough shaped enclosure secured thereto.
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4. An inflatable support appliance as claimed in claim 3 wherein the inlets for said enclosures are connected to a common inlet conduit connected to said air supply means, the air inlet conduit having a valve control to adjust the pressure supplied to the enclosures.
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5. An inflatable support appliance as claimed in claim 4 comprising a number of said bases arranged side by side so that the enclosures form a mattress.
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6. An inflatable support appliance as claimed in claim 3 wherein each trough has an outlet and the outlets for each set of troughs are connected to a common outlet pipe to exhaust air from the enclosures at a location remote from the enclosures.
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7. An inflatable support appliance as claimed in claim 1 and comprising a plurality of gas-inflatable elements each associated with a respective collapsible portion whereby in operation said surface is able yieldingly to conform to a load supported on said surface by collapse of the collapsible portions associated with hose elements engaged by the load, and at least the upwardly facing parts of said elements being formed from said flexible and extensible continuous material.
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8. An inflatable support appliance as claimed in claim 1 wherein each element is a generally upstanding tube closed at its upper end by said flexible gas permeable material and having a semi-collapsed lower portion in the form of a rolling diaphragm.
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9. An inflatable support appliance as claimed in claim 1 wherein the surface of the appliance intended to make contact with a user comprises a number of rows of frusto-pyramids formed in said flexible and extensible continuous material.
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10. An inflatable support appliance as claimed in claim 9 wherein said surface comprises a cell having the shape of an inverted hollow frusto-pyramid and having flexible sidewalls.
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11. An inflatable support appliance as claimed in claim 10 wherein both said surface and the cell are formed from heat bondable material and the frusto-pyramids of the said surface are joined by heat bonding around their lower peripheries and said surface is joined to the inverted frusto-pyramid by heat bonding.
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12. An inflatable support appliance as claimed in claim 10 wherein the cell is elongate in one direction to form a mattress or a number of the cells are arranged side by side to form a mattress.
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13. An inflatable support appliance as claimed in claim 5 wherein the appliance is mounted on a bed frame having a number of elements which can be articulated with respect to one another about horizontal axes and which is mounted on a base for pivotal adjustment about a horizontal axis to vary the attitude of the frame as a whole.
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14. An inflatable support appliance as claimed in claim 1 wherein said flexible and extensible continuous material comprises a continuous plastics coating capable of transmitting water vapour and a backing layer on which the coating is supported.
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15. An inflatable support appliance as claimed in claim 14 wherein the plastics coating is polyurethane, silicone or vinyl copolymer resin.
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16. An inflatable support appliance as claimed in claim 14 wherein the plastics coating is capable of transmitting water vapour at a rate of at least 230g/sq.in./24 hours at 37*C.
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17. An inflatable support appliance as claimed in claim 14 wherein the backing layer if a woven, non-woven or knitted nylon or a polyester fabric.
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18. An inflatable support appliance as claimed in claim 1 wherein valve means are provided for controlling the flow of air through said outlet.
Specification