Check valve for mattress assembly

Information

  • Patent Grant
  • 6418579
  • Patent Number
    6,418,579
  • Date Filed
    Monday, June 4, 2001
    23 years ago
  • Date Issued
    Tuesday, July 16, 2002
    22 years ago
Abstract
A check valve adapted for use between first and second fluid chambers. The check valve is configured to prevent fluid flow from the second fluid chamber into the first fluid chamber.
Description




BACKGROUND AND SUMMARY OF THE INVENTION




The present invention relates to a mattress, a mattress overlay, or a mattress replacement assembly including an air cushion having air zones for supporting a person, and to a pressure control assembly for controlling the pressure of pressurized fluid contained by the air zones of the air cushion.




Some mattresses, mattress overlays, or mattress replacement systems (hereinafter mattresses) are provided with air sacks to support a person and to provide adjustable firmness characteristics. These air mattresses include one, or several air sacks that are inflated to different pressures to adjust the firmness in selective regions or zones of the mattress. One such mattress is illustrated in U.S. Pat. No. 5,794,288, entitled PRESSURE CONTROL ASSEMBLY FOR AN AIR MATTRESS, which is herein incorporated by reference.




It is desirable for an air mattress to provide different pressure zones of support for a person on the mattress while maintaining sufficient pressure along opposite side edges of the mattress to provide support when the person sits or rests along one of the side edges. In the illustrated embodiment, each air zone is in fluid communication with a manifold having an interior region that is maintained at a constant pressure. The constant pressure of the pressurizing fluid within the manifold may be the same as or may be different from the pressure of pressurized fluid within at least one of the air zones. The illustrated air cushion also includes first and second side bolsters filled with air that extend along opposite sides of the air cushion to help retain a person on the air cushion.




In the illustrated embodiment of the present invention, a mattress assembly comprises an inflatable central support portion having a head end, a foot end, a first side and a second side, and first and second side bolsters coupled to the first and second sides, respectively. The first and second side bolsters each have at least two chambers extending along a longitudinal axis of the first and second side bolsters. At least one of the chambers is a manifold in fluid communication with the central support portion. The manifold is configured to be coupled to an air supply to supply air to the central support portion and the other chambers.




Also in the illustrated embodiment, the inflatable central support and the first and second side bolsters are formed from a plurality of separately inflatable zones. The plurality of zones include a head zone, a shoulder zone, a seat zone, and a foot zone. The illustrated first and second side bolsters each include a top chamber, a central chamber, and a bottom chamber. The central chamber of the first side bolster is illustratively the manifold extending along the first side of the central support portion. The central chamber of the first side bolster is in fluid communication which each of the plurality of zones of the central support portion. The zones of the top and bottom chambers of the of the first and second side bolsters are each in fluid communication with the central support portion through a restricted flow orifice. illustratively, the zones of the central chamber of the second side bolster are coupled to the top chambers of the second side bolster through a restricted flow orifice. Also illustratively, the bottom chambers in the shoulder zone of the of the first and second side bolsters are coupled to the central support portion by check valves which permit air flow from the central support portion into the bottom chambers in the shoulder zone.




Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of an illustrated embodiment exemplifying the best mode of carrying out the invention as presently perceived.











BRIEF DESCRIPTION OF THE DRAWINGS




The detailed description particularly refers to the accompanying figures in which:





FIG. 1

is an exploded perspective view of a mattress assembly of the present invention including an air cushion having a plurality of separate air zones, top coverlet, a bottom cover, and a blower configured to be coupled to the air cushion;





FIG. 2

is a sectional view taken through a head zone of the air cushion;





FIG. 3

is a sectional view taken through a shoulder zone of the air cushion;





FIG. 4

is a sectional view taken through a seat zone of the air cushion;





FIG. 5

is a sectional view taken through a foot zone of the air cushion;





FIG. 6

is a top plan view of the air cushion of

FIG. 1

;





FIG. 7

is a bottom plan view of the air cushion;





FIG. 8

is a perspective view of a check valve of the present invention in an open orientation to permit air flow from a manifold into a central support portion of the air cushion;





FIG. 9

is a perspective view of the check valve of

FIG. 8

illustrating the check valve in a closed position; and





FIG. 10

is a perspective view of a portion of the air cushion illustrating a plurality of chambers within a side bolster located adjacent to a support zone of the air cushion.











DETAILED DESCRIPTION OF THE DRAWINGS




Referring now to the drawings,

FIG. 1

illustrates a mattress assembly


10


including an air cushion


12


configured to be located between a top coverlet


14


and a bottom cover


16


. Illustratively, top coverlet


14


includes a top surface


18


and a side flap


20


. A zipper


22


extends around the coverlet


14


beneath the flap


20


. Zipper


22


is configured to be coupled to a zipper


24


of bottom cover


16


so that the flap


20


extends downwardly over zipper


24


. Zipper


24


is coupled to a side wall


26


of cover


16


which extends upwardly from a bottom surface


28


. Coverlet


14


and bottom cover


16


cooperate to define an interior region


30


for receiving the air cushion


12


. Buckles


32


are coupled to opposite sides of cover


16


to secure the mattress assembly


10


to a box spring or a support deck. In addition, bottom cover


16


includes tie straps


34


which may also be used to secure the mattress assembly


10


to a support deck.




Air cushion


12


includes a side flap


43


adjacent each side bolster


42


and


44


. Snaps


45


are located on each flap


43


. Snaps


45


are configured to mate with snaps


47


on side wall


26


of bottom cover


16


. It is understood that other suitable fasteners, such as Velcro fasteners, ties, etc. may be used instead of snaps


45


and


47


.




Air cushion


12


includes a central support portion


40


which provides a sleep surface for a person resting on the mattress. Air cushion


12


also includes side bolsters


42


and


44


located on opposite sides of the central support portion


40


. Air cushion


12


is illustratively divided into separate air zones including a head zone


46


, a shoulder zone


48


, a seat zone


50


, and a foot zone


52


. A hose fitting


54


is coupled to the side bolster


42


in the foot zone


52


. Fitting


54


is configured to be coupled to a connector


56


on air hose


58


. A connector


60


on the opposite end of hose


58


is configured to be coupled to an outlet


62


of a blower


64


. Connector


56


extends through an aperture


66


formed in bottom cover


16


and into the hose fitting


54


to supply air from the blower


64


to the air cushion


12


as discussed in detail below.




Each of the air zones


46


,


48


,


50


, and


52


are separated by a solid divider wall


68


,


70


, and


72


as best illustrated in FIG.


6


. The central support portion


40


further includes baffles


74


located within each zone. Baffles


74


include apertures


76


which permit air flow through the baffles


74


.




First side bolster


42


includes a top chamber


80


, a bottom chamber


82


, and a central manifold


84


. Second side bolster


44


includes a top chamber


86


, a bottom chamber


88


, and a central chamber


90


. Top and bottom chambers


80


and


82


of side bolster


42


are divided into separate zones by dividers


68


,


70


, and


72


shown in FIG.


6


. Manifold


84


extends continuously through the first side bolster


42


so that manifold


84


supplies air from the blower


64


to each of the separate air zones


46


,


48


,


50


, and


52


of the air cushion


12


. A split corrugated hose


92


extends through the manifold


84


to prevent opposite side walls of the manifold


84


from collapsing together to block air flow through one of the air zones.




As shown in

FIG. 5

, inlet air from blower


64


passes through hose


58


and hose fitting


54


into bottom chamber


82


of foot zone


52


. Bottom chamber


82


is in fluid communication with manifold


84


within foot zone


52


. Therefore, air flows through the manifold


84


along the entire side bolster


42


.




Referring now to

FIG. 2

, the configuration of the head zone


46


of the air cushion


12


is illustrated. The central support portion


40


has a thickness illustrated by dimension


94


. Side bolsters


42


and


44


have a thickness illustrated by dimension


96


which is greater than the thickness of the support portion


40


. The increased thickness of side bolsters


42


and


44


helps to maintain a person on the air cushion


12


. The top and bottom chambers of the side bolsters


42


,


44


simulate a rectangular shape and provide an increased sleep surface area compared to a single round side bolster chamber.




In head zone


46


, air from manifold


84


passes into central support portion


40


through a check valve


98


in the direction of arrow


100


to supply the central support portion


40


with air from the blower


64


. Air from central support portion


40


passes through a restricted flow orifice


102


into top chamber


80


and through a restricted flow orifice


104


into bottom chamber


82


of side bolster


42


. In addition, air from central portion


40


passes through a restricted flow orifice


106


into top chamber


86


of side bolster


44


and through restricted flow orifice


108


into bottom chamber


88


of side bolster


44


. Air also passes from top chamber


86


to central chamber


90


of side bolster


44


through a restricted flow orifice


110


. Illustratively, orifices


102


,


104


,


106


,


108


, and


110


all have a size of ⅛ inch. A dump valve


112


is coupled to central portion


40


to permit the head zone


46


to be deflated quickly. A test port


114


is also coupled to central support portion


40


. Test port


114


is configured to receive a needle to check the pressure within zone


46


.





FIG. 3

illustrates the configuration of the air cushion


12


in the shoulder zone


48


. Air from the manifold


84


passes through a check valve


116


into central support portion


40


in the direction of arrow


118


. Air from central support portion


40


flows into top chamber


80


of side bolster


42


through an orifice


120


. Air from central support portion


40


also passes through a check valve


122


into bottom chamber


82


of side bolster


42


in the direction of arrow


124


. In addition, air from central support portion


40


passes into top chamber


86


of side bolster


44


through a restricted flow orifice


126


. Air from chamber


86


passes into central chamber


90


through orifice


128


. Air also passes from central support portion


40


through a check valve


130


into bottom chamber


88


of side bolster


44


in the direction of arrow


132


. Illustratively, orifices


120


,


126


, and


128


have a dimension of ⅛ inch. Dump valves


131


and


133


are coupled to bottom chambers


82


and


88


, respectively, of shoulder zone


48


.




Check valves


122


and


130


permit air to enter bottom chambers


82


and


88


, respectively. However, air cannot pass back through check valves


122


and


130


into the central support portion


40


. Therefore, these bottom chambers


82


and


88


within shoulder zone


48


remain at relatively high pressure to provide additional support in bolsters


42


and


44


within the shoulder zone. As the weight of the patient increases, the pressure within bottom chambers


82


and


84


within shoulder zone


48


also increases.





FIG. 4

illustrates the configuration of the air cushion


12


within the seat zone


50


. Air manifold


84


is coupled to central support portion


40


by an orifice


134


. Illustratively, orifice


134


has a dimension of ⅜ inch. Therefore, the pressure within central support portion


40


of seat zone


50


is maintained at substantially the air manifold pressure. Air passes from central support portion


40


into top chamber


80


and bottom chamber


82


of side bolster


42


through restricted flow orifices


136


and


138


, respectively. Air also passes from central support portion


40


into top chamber


86


and bottom chamber


88


of side bolster


44


through restricted flow orifices


140


and


142


, respectively. Air passes from top chamber


86


to central chamber


90


of side bolster


44


through a restrictive flow orifice


144


. Illustratively, orifices


136


,


138


,


140


,


142


, and


144


each have a dimension of ⅛ inch. Dump valves


146


and


148


are coupled to bottom chambers


82


and


88


, respectively. A test port


114


is coupled to central support portion


40


.




A configuration of foot zone


52


of air cushion


12


is illustrated in FIG.


5


. Air manifold


84


is coupled to central support portion


40


of foot zone


52


by a check valve


150


so that air flows from manifold


84


into central support portion


40


in the direction of arrow


152


. Air passes from central support portion


40


into top chamber


80


of side bolster


42


through restricted flow orifice


154


. Air also passes into top chamber


86


and the bottom chamber


88


of side bolster


44


through restrictive flow orifices


156


and


158


, respectively. Air flows from top chamber


86


to central chamber


30




90


of side bolster


44


through restricted flow orifice


160


. Illustratively, orifices


154


,


156


,


158


, and


160


have a dimension of ⅛ inch. A dump valve


162


is coupled to central support portion


40


within foot zone


52


. A test port


114


is also coupled to central support portion


40


within foot zone


52


.




Air pressure within each of the air zones


46


,


48


,


50


, and


52


is controlled by the number of micro holes


172


formed in a top surface


170


of each zone of the central support portion


40


. Illustratively, head zone


46


includes 12-16 micro holes


172


, shoulder zone


48


includes 20-24 micro holes, seat zone


50


includes 12 micro holes, and foot zone


52


includes 36-48 micro holes. The number of micro holes


172


in each zone


46


,


48


,


50


, and


52


controls the pressure within the zone since the same manifold pressure from air manifold


84


is supplied to each zone. Therefore, pressure within the zones


46


,


48


,


50


, and


52


can be established at a desired level by altering the size or number of micro holes


172


formed in top surface


170


of central support surface


40


. In another embodiment, a separate orifice is coupled to the central support portion


40


in each zone to adjust the air flow out of the zone without micro holes being formed in the top surface


170


. As shown in

FIG. 7

, bleeder valves


174


,


176


are coupled to a bottom surface


178


of air cushion


12


in communication with the head zone


46


and foot zone


52


. Bleeder valves


174


,


176


further reduce the pressure in head zone


46


and foot zone


52


. When bleeder valves


174


,


176


are used, micro holes


172


are not used to vent head zone


46


and foot zone


52


.




The side bolsters


42


and


44


help retain a person on the central support portion


40


as the person moves toward an edge of the mattress. Since air flow out of the side bolsters


42


,


44


is restricted, air cannot rush to an opposite side of the air cushion


12


as the person moves toward a side of the air cushion


12


. The number of micro holes


172


is illustratively selected so that the seat zone


50


has the highest pressure. Shoulder zone


48


illustratively has the next highest pressure. Head zone


46


and foot zone


52


have the lowest pressures.




The mattress assembly


10


of the present invention may be used as a mattress overlay or as a mattress replacement. Typically, the thickness of the mattress overlay is less than the thickness for a mattress replacement air cushion. If desired, such as in a mattress replacement situation, the orifices


138


and


142


of seat zone


50


may be replaced with check valves such as illustrated by check valves


122


and


130


in

FIG. 3

so that air is forced into bottom chambers


82


and


88


based on the weight of the patient. If such check valves are used, air cannot return from bottom chambers


82


and


88


of the seat zone


50


to the central portion


40


as discussed with regard to FIG.


3


. Therefore, this embodiment would provide additional stiffness for the side bolsters


42


,


44


.





FIGS. 8 and 9

illustrate a check valve


180


of the present invention. Check valve


180


is illustratively formed from two sheets


181


,


183


of high temperature urethane material having a thickness of about 0.008 inch. The thickness may be less if desired. The sheets are seam sealed to an air zone surface around a tube


182


by seams


184


. Tube


182


includes an angle cut end


185


to reduce the likelihood that the tube


182


will be sealed by a portion of manifold


84


. Seals such as RF welds are also provided at locations


186


and


188


to provide a generally T-shaped open region


190


between the sheets


181


,


183


of the valve


180


. Open region


190


has air outlet openings


191


which are not sealed by seams. Air can flow through the tube


182


in the direction of arrow


192


. Air the passes into region


190


as illustrated by arrows


194


in FIG.


8


and exits the valve


180


through openings


191


as illustrated by arrows


196


. The sheets


181


,


183


of valve


180


collapse and block air flow through the region


190


in the direction of arrows


197


to provide a check valve as shown in FIG.


9


. Dimension


198


of valve


180


is illustratively 3.250 inches. Dimension


200


of valve


180


is illustratively 2.375 inches. Dimension


204


of valve


180


is illustratively 1.000 inch.




Additional details of the air cushion


12


are illustrated in FIG.


10


. Air cushion


12


includes a top sheet of material


210


and a bottom sheet of material


212


which extend across the entire width of the air cushion


12


. Baffles


74


are coupled to top sheet


210


and bottom sheet


212


by seams


214


and


216


, respectively. Air cushions


212


further include upper and lower interior sheets of material


218


and


220


which form the side bolsters


42


and


44


. Only one side bolster


42


is illustrated in FIG.


10


.




Upper sheet


218


is coupled to top sheet


210


by seam


222


. Sheet


218


is also coupled to top sheet


210


at a spaced-apart location


224


to define the top chamber


80


of bolster


42


. Sheets


210


,


212


,


218


, and


220


are all coupled together by seam


222


adjacent flap


43


. Lower sheet


220


is coupled to bottom sheet


212


by seam


228


. Lower sheet


220


is also coupled to upper sheet


218


by seam


184


. Illustratively, the check valve


180


is coupled to the top and bottom sheets


218


and


220


as shown in FIG.


10


.




Lower sheet


220


is also coupled to bottom sheet


212


at a location


230


spaced apart from seam


228


to define bottom chamber


82


of bolster


42


. Manifold


84


is formed between upper and lower sheets


218


and


220


between seams


184


,


224


,


226


, and


230


.




Hose


92


extends through manifold


84


as shown in

FIG. 10

to prevent the sheets


218


and


220


which form manifold


84


from collapsing against each other to seal the manifold


84


. Tube


92


is split along its length as shown by split


232


. Therefore, air can flow through the tube


92


and through the split portion


232


. In other words, tube


92


provides structural support within the manifold


84


to hold the manifold


84


open. It is understood that other structural support members such as springs, etc. which permit air flow through the support member may be used in accordance with the present invention.




Although the invention has been described in detail with reference to certain illustrated embodiments, variations and modifications exist within the scope and spirit of the invention as defined by the following claims.



Claims
  • 1. A check valve for use in a mattress assembly including an inflatable central support portion and a manifold in fluid communication with the central support portion, the manifold being configured to be coupled to an air supply to supply air to the central support portion, the check valve comprising:a substantially planar top sheet; a substantially planar bottom sheet disposed substantially parallel to the top sheet; at least one seal securing the top sheet and the bottom sheet, and defining an open region between the top sheet and the bottom sheet, the open region including at least one air opening located within the central support portion; and a tube positioned intermediate the top sheet and the bottom sheet, the top sheet and the bottom sheet being sealed around the tube and secured to the manifold, the tube having a first end extending within the manifold, a second end extending within the central support portion, and an air inlet defined by the first end, wherein the at least one air opening is configured to permit air flow in a first direction from the manifold into the central support portion, while preventing air flow in a second direction from the central support portion into the manifold.
  • 2. The check valve of claim 1, wherein the tube has an angled end surface.
  • 3. The check valve of claim 1, wherein the central support portion and the manifold of the mattress are separated by an elongated seam, the seam being formed to provide a seal to secure the top and bottom sheets to the tube.
  • 4. The check valve of claim 3, wherein the seam is formed by a RF weld.
  • 5. The check valve of claim 1, wherein the central support portion and the manifold are also formed from substantially planar sheets of material.
  • 6. A check valve for use in a mattress assembly including an inflatable central support portion and a manifold in fluid communication with the central support portion, the manifold being configured to be coupled to an air supply to supply air to the central support portion, the check valve comprising:a top sheet; a bottom sheet disposed substantially parallel to the top sheet; and a tube positioned intermediate the top sheet and the bottom sheet, the top sheet and the bottom sheet sealed around the tube to provide an air inlet located within the manifold, the top and bottom sheets cooperating to define two air openings located within the central support portion, the two air openings being configured to permit air flow in first and second directions from the manifold into the central support portion, while preventing air flow in a third direction from the central support portion into the manifold.
  • 7. The check valve of claim 6, wherein the central support portion and the manifold of the mattress are separated by an elongated seam, the seam being formed to provide a seal to secure the top and bottom sheets to the tube.
  • 8. The check valve of claim 7, wherein the seam is formed by a RF weld.
  • 9. The check valve of claim 6, wherein the central support portion and the manifold are also formed from substantially planar sheets of material.
  • 10. A check valve for use between first and second fluid chambers, the check valve comprising:a first sheet extending between the first and second fluid chambers; a second sheet extending between the first and second fluid chambers and sealed to the first sheet to define a fluid outlet, the fluid outlet positioned within the second fluid chamber wherein fluid pressure within the second fluid chamber forces the first and second sheets toward the other of the first and second sheets, thereby preventing fluid flow from the second fluid chamber into the first fluid chamber; and a tube positioned intermediate the first and second sheets, the first and second sheets being sealed around the tube, the tube having opposing first and second ends, the first end of the tube maintaining the first and second sheets in spaced relation within the first fluid chamber and forming a fluid inlet in fluid communication with the first fluid chamber, wherein fluid supplied from the tube forces the first and second sheets away from the other of the first and second sheets proximate the second end of the tube, thereby permitting fluid flow from the first fluid chamber into the second fluid chamber.
  • 11. The check valve of claim 10, wherein the first and second sheets cooperate to define two fluid openings located within the second fluid chamber.
  • 12. The check valve of claim 10, wherein the tube has an angled end surface.
  • 13. The check valve of claim 10, wherein the first fluid chamber comprises a manifold being configured to be coupled to an air supply to supply air to the second fluid chamber, and the second fluid chamber comprises an inflatable central support portion of a mattress assembly.
  • 14. The check valve of claim 10, wherein the first and second fluid chambers are separated by an elongated seam, the seam being formed to provide a seal to secure the first and second sheets to the tube.
  • 15. The check valve of claim 14, wherein the seam is formed by a RF weld.
  • 16. The check valve of claim 10, wherein the first and second fluid chambers are also formed from substantially planar sheets of material.
  • 17. A check valve comprising:a first planar sheet; a second planar sheet disposed substantially parallel to the first sheet; at least one seal securing the first sheet and the second sheet, and defining an open region between the first sheet and the second sheet; a tube disposed intermediate the first and second sheets, the first and second sheets sealed around the tube to prevent fluid flow between the first and second sheets and the tube; and the open region including at least one outlet positioned in spaced relation to the tube, the at least one outlet configured to permit fluid flow in a first direction from the tube to the at least one outlet, while preventing fluid flow in a second direction from the at least one outlet to the tube.
  • 18. The check valve of claim 17, wherein the tube is in fluid communication with a first fluid chamber.
  • 19. The check valve of claim 18, wherein the outlet is in fluid communication with a second fluid chamber, and the first and second sheets are disposed within the second fluid chamber wherein fluid pressure within the chamber tends to force the first and second sheets into sealing engagement.
  • 20. The check valve of claim 17, wherein the tube maintains the first and second sheets in spaced relation.
  • 21. The check valve of claim 17, wherein the first and second sheets are formed of a urethane material.
  • 22. The check valve of claim 17, wherein the tube has an angled end surface.
  • 23. The check valve of claim 17, wherein the at least one outlet comprises a pair of openings disposed substantially perpendicular to the tube.
  • 24. The check valve of claim 17, wherein the first and second fluid chambers are separated by an elongated seam, the seam being formed to provide a seal to secure the first and second sheets to the tube.
  • 25. The check valve of claim 24, wherein the seam is formed by a RF weld.
  • 26. The check valve of claim 17, wherein the first and second fluid chambers are also formed from substantially planar sheets of material.
  • 27. A check valve for use in a mattress assembly including an inflatable central support portion and a manifold in fluid communication with the central support portion, the manifold being configured to be coupled to an air supply to supply air to the central support portion, the check valve comprising:a top sheet; a bottom sheet disposed substantially parallel to the top sheet; at least one seal securing the top sheet and the bottom sheet, and defining an open region between the top sheet and the bottom sheet including an outlet and an inlet; and an elongated seam separating the manifold and the central support portion of the mattress, the seam being formed to provide a seal to secure together the top and bottom sheets to position the outlet in the central support portion and the inlet in the manifold.
  • 28. The check valve of claim 27, further comprising a tube positioned intermediate the top sheet and the bottom sheet, the seam securing the tube to the top and bottom sheets.
  • 29. The check valve of claim 27, wherein the seam is formed by a RF weld.
  • 30. The check valve of claim 27, wherein the central support portion and the manifold are also formed from substantially planar sheets of material.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 09/479,353 filed Jan. 7, 2000, now U.S. Pat. No. 6,240,584 which claims the benefit of U.S. provisional application Serial No. 60/115,116, filed Jan. 8, 1999, the disclosures of which are expressly incorporated by reference herein.

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Provisional Applications (1)
Number Date Country
60/115116 Jan 1999 US
Continuations (1)
Number Date Country
Parent 09/479353 Jan 2000 US
Child 09/873540 US