Mattress and method for preventing accumulation of carbon dioxide in bedding

Information

  • Patent Grant
  • 6370718
  • Patent Number
    6,370,718
  • Date Filed
    Monday, February 14, 2000
    24 years ago
  • Date Issued
    Tuesday, April 16, 2002
    22 years ago
Abstract
A mattress assembly, comprising: substantially nonporous bottom and side walls forming a mattress foundation; a mattress inner core disposed in the mattress foundation being permeable to air; nonporous top cover covering the mattress inner core, the nonporous top cover having apertures at predetermined locations to allow the flow of air therethrough; and a fan disposed with the mattress assembly for forcing air into the mattress inner core whereby the air is forced out the top cover so as to reduce the accumulation of carbon dioxide in bedding on the top cover of the mattress.
Description




BACKGROUND OF THE INVENTION




The present invention relates to an apparatus and method for preventing the accumulation of carbon dioxide in bedding which is believed to be a cause or contributing factor in Sudden Infant Death Syndrome (SIDS).




Many efforts have been made to produce a mattress assembly which will prevent or reduce the occurrence of SIDS. Unfortunately, most of these approaches do not offer a good solution. The present invention solves many of the problems or shortcomings of the prior art mattress assemblies.




SUMMARY OF THE INVENTION




The present invention relates to an apparatus and method for preventing the accumulation of carbon dioxide in bedding which is believed to be a cause or contributing factor in Sudden Infant Death Syndrome (SIDS).




In one embodiment, the invention relates to a mattress assembly, comprising: substantially nonporous bottom and side walls forming a mattress foundation; a mattress inner core disposed in the mattress foundation being permeable to air; a nonporous top cover covering the mattress inner core, the nonporous top cover having apertures at predetermined locations to allow the flow of air therethrough; and a fan disposed with the mattress assembly for forcing air into the mattress inner core whereby the air is forced out the top cover so as to reduce the accumulation of carbon dioxide in bedding on the top cover of the mattress.




In another embodiment, the invention relates to a method of reducing the accumulation of carbon dioxide in bedding, comprising the steps of: forming a mattress having substantially nonporous bottom and side walls and a nonporous top cover having apertures at predetermined locations to allow the flow of air therethrough; and forcing air into an interior area of the mattress at a sufficient rate to percolate air through the top cover of the mattress.




In yet another embodiment, the invention relates to a mattress assembly having molded retaining means thereon, an inner core within the mattress assembly, a top cover and bedding attachable to the mattress foundation by the retaining means, and a fan in the mattress assembly for forcing fresh air through the mattress assembly.




These and various other advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the accompanying drawings and descriptive matter, which form a further part hereof, and in which there is illustrated and described a preferred embodiment of the invention.











BRIEF DESCRIPTION OF THE DRAWINGS




In the drawings wherein like reference numerals indicate corresponding parts throughout the several views:





FIG. 1

is a perspective view of a preferred embodiment of a mattress assembly in accordance with the principles of the present invention disposed in a crib, an infant being illustrated as resting on the mattress assembly;





FIG. 2

is an exploded view of the mattress assembly shown in

FIG. 1

;





FIG. 3

is an enlarged partial sectional view illustrating air flow from the innerspring of the mattress assembly through the frame and bumper assembly and out the side walls of the frame and bumper assembly into the infant sleeping area;





FIG. 4

is a partial perspective view illustrating an embodiment of a latch mechanism for latching the frame assembly onto the sidewalls of the mattress assembly foundation;





FIG. 5

is a partial perspective view illustrating the frame assembly being pivoted into an open position whereby it is no longer resting on top of the sidewalls of the mattress assembly foundation;





FIG. 6

is a partial side view of fastener mechanism for fastening the bumper assembly onto the frame assembly;





FIG. 7

is a partial cross sectional view illustrating an embodiment of the fan assembly disposed in a sidewall of the mattress assembly foundation;





FIG. 8

is a planar view of a top cover of the mattress assembly;





FIG. 9

is an alternate embodiment of an apparatus for attaching the top surface of the mattress assembly and the mattress bedding onto the mattress foundation;





FIG. 10A

is an exploded view of an alternate embodiment of the mattress assembly; and





FIGS. 10B and 10C

are partial cross-section views illustrating alternative methods of fastening the mattress bedding.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Referring now to the drawings there is shown a preferred embodiment of a mattress assembly in accordance with the principles of the present invention, the mattress assembly being generally referred to by the reference numeral


30


. The mattress assembly


30


is shown in

FIG. 1

as being disposed in a conventional crib


32


with an infant


34


resting on the mattress assembly


30


. It will be appreciated that the mattress assembly


30


might be used with or without a conventional crib


32


as shown.




Illustrated in

FIG. 2

is an exploded view of the embodiment of the mattress assembly


30


shown in FIG.


1


. The mattress assembly


30


shown includes a foundation


40


, an innerspring


50


, a top cover


60


, mattress bedding


70


, a frame assembly


80


, and a bumper assembly


90


.




The foundation


40


includes substantially nonporous side walls


41


and a bottom wall


42


so as to form an air impermeable foundation for the mattress. The walls


41


,


42


might be molded as a single piece from plastic or the like. Angle brackets


47


are shown disposed on the bottom wall


42


for centering the inner spring


50


. These angle brackets


47


might be separate pieces or they might be integrally molded with the foundation


40


.




As shown in

FIGS. 1-2

,


4


&


7


, disposed in the side walls


41


is a fan assembly housing


43


housing a fan


49


. As shown in

FIG. 2

, disposed on a top surface of the bottom wall is a heater


45


. As shown in

FIG. 7

, in other embodiments, a heater might be present in the fan housing


43


as a heater coil


46


or the like.




The fan housing


43


will include suitable circuitry for controlling operation of the fan


49


and the heater


45


/


46


. In the embodiment shown there are two switches


44




a,b.


Switch


44




a


is a master on off switch for the fan


49


and the heater


45


/


46


and switch


44




b


is for the heater


45


/


46


only.




As shown in

FIGS. 2 and 3

, the inner spring


50


is removably mounted in the mattress foundation


40


. The inner spring


50


includes a plurality of coils


54


defining an open area for air flow. Air flow in the several views is generally illustrated by the arrows


56


. In addition to or as opposed to the angle brackets


47


, the mattress foundation


40


might further include individual guides or receptors (not shown) disposed on the bottom wall


42


for receiving each of the coils


54


to further assist in positioning of the inner spring


50


. The inner spring


50


is preferably made of non-corrosive, washable material because of possible contact with saliva, sputum, urine, etc. A preferred material is galvanized spring steel.




As illustrated in

FIG. 8

, the top cover


60


is preferably made of a soft, nonporous material such as natural or synthetic rubber, vinyl, etc. so as to not harbor and provide a growth environment for bacteria or the like. Holes


61


are spaced preferably less than 2 cm apart, more preferably less than 1.5 cm apart, and most preferably on 1 cm staggered centers or less to insure that air is delivered from the innerspring


50


through the top cover


60


to at least one nostril of the infant. The diameter of the holes


61


must be large enough to prevent closing from lint, dust, etc. and yet small enough to build static pressure adequate to force air with sufficient velocity through the bedding. Over pressurizing will create air flow volumes that may cause hypothermia in infants. Under pressurizing will not have the desired effect on the bedding. Hole diameter should preferably be {fraction (3/16)} inches when using fan volumes of 100 cubic feet per minute (cfm) to 170 cfm at static pressures of 0.04 inches H


2


O to 0.08 inches H


2


O and most preferably ⅛ inch diameter when used with total air flow of 25 cfm to 55 cfm at 0.01 inches H


2


O to 0.05 inches H


2


O static.




As illustrated in

FIG. 2

, the top cover


60


of the mattress includes apertures


62


, such as eyelets or grommets, which are receivable on spaced apart projections


64


disposed on top of the side walls


41


, whereby the top cover


60


is attached to the mattress foundation


40


in a taut condition. Likewise the bedding


70


is shown as including elasticized straps


72


about its periphery with apertures


74


, such as eyelets or grommets, which are receivable on the projections


64


, whereby the mattress bedding


70


is attached to the mattress foundation in a taut condition. In the embodiment shown, the projections are angled outward so as to facilitate retention of the top cover


60


and the bedding


70


. In the preferred embodiment, the top cover


60


and the bedding


70


are taut when secured onto the projections


64


. As can be seen the top cover


60


is readily removable to facilitate the cleaning of its top and bottom surfaces of saliva, sputum, urine, etc. that may collect on the top cover


60


or pass through the apertures


61


to the bottom surface of the top cover


60


. The top cover


60


is simply removed or placed in position by sliding it off of and onto the projections


64


.




It will be appreciated that other structures or methods might be utilized to removably mount and remove the top cover


60


without requiring tools. For example, as illustrated in

FIG. 9

, the top cover


60


and likewise the bedding


70


, might include hooks


75


for engaging an overhanging portion


77


of the foundation


40


created by an indentation


73


disposed about the perimeter of the foundation


40


in the outside surface of the side walls


41


. Preferably the hooks


75


of the bedding


70


and the top cover


60


would be spaced apart from one another so they do not overlap. This arrangement would allow the hooks


75


to be attached at any location about the perimeter of the foundation


40


. Of course, in alternate embodiments tools might be required.




In the preferred embodiment, the mattress bedding


70


functions both as a mattress pad and sheet. Preferably the bedding


70


is of sufficient thickness to assure infant comfort yet be constructed of a material that when used in conjunction with the specified air flow and velocity prevents dangerous accumulations of carbon dioxide. A preferred embodiment shall be a coarsely woven, linen-like outer layer sandwiching a natural cotton batting interior devoid of resins or glues. In alternate embodiments, other porous materials might be used.




As noted above, the mattress bedding


70


is attached to the projections


64


on the foundation


40


and then the frame assembly


80


is disposed over the straps


72


. The edges of the mattress bedding


70


might then be suitably attached to the frame assembly


80


and/or bumper assembly


90


by the use of straps of material


76


suitably secured to the bedding


70


which can be wrapped up and over the frame assembly


80


and/or the bumper assembly


90


and fastened thereto by VELCRO™ strips


93


or the like. In an alternate embodiment, the mattress bedding


70


might attach directly to the frame assembly


80


and/or the bumper assembly


90


so as to obviate the need to remove and replace the frame/bumper assembly when changing sheets.




The mattress foundation


40


preferably shall include rigid, impermeable, nonporous material such as plastic or wood. This will provide rigidity for keeping the top cover


60


and the mattress bedding


70


taut. As shown in

FIGS. 2 and 7

, it will provide a rigid compartment for installing the fan housing


43


. The mattress foundation is preferably made of a material which is easily cleaned and resistant to harboring bacteria.




In the preferred embodiment, the innerspring


50


has a slightly smaller outer dimension than the inner dimension of the frame assembly


80


and is slightly higher so that when the frame assembly


80


and/or bumper assembly


90


is attached, the top cover


60


and the mattress bedding


70


are pulled down over the edges of the innerspring


50


thereby forming a slightly convex top surface.




The frame assembly


80


and the bumper assembly


90


might be a single assembly as opposed to two separate assemblies. The frame assembly


80


preferably has a height of 1.5 inches or less while the bumper assembly


90


preferably has a height of 4 to 6 inches. As shown in

FIG. 3

, both assemblies preferably comprise a rigid frame


81


and


91


respectively covered with a nonporous material


82


and


92


, respectively, having a plurality of apertures in it. The configuration and arrangement of the apertures is preferably the same as that for the top cover


60


.




As shown in

FIG. 3

, a bottom edge of the frame assembly


80


is preferably open to allow flow of air from the innerspring


50


through the top cover


60


and into a cavity in the frame assembly


80


. The air will then pass out the apertures in the material


82


and into a cavity of the bumper assembly


90


where in turn the air will then pass out the apertures in the material


92


as generally illustrated by the arrows


56


. The frame assembly


80


will provide a seal with the top surface of the mattress foundation to prevent air leakage out the sides of the mattress assembly. As shown in

FIG. 3

, the frame assembly


80


includes cavities


88


in alignment with and positionable over the projections


64


so as to allow the frame assembly


80


to form a seal with the mattress foundation


40


.




As shown in

FIGS. 4 and 5

, mechanical latches


86


preferably requiring no tools, attach the frame assembly


80


to the mattress foundation


40


and allow the frame assembly


80


to be removed and/or pivoted upward as shown in FIG.


5


. Latches


96


, preferably requiring no tools, attach the bumper assembly


90


to the frame assembly


80


. In the preferred embodiment the latches


96


can be moved laterally to avoid interference with crib pickets.




The fan assembly is preferably a modularized assembly for easy removal by hand and without the aid of tools. In this way, the mattress assembly


30


can be sold with or without the fan assembly. The fan assembly preferably can be readily added or replaced as needed. Preferably the fan assembly is compatible with future portable mattresses such as those used in bassinets or other types of portable playpens. As shown in

FIG. 2

, upon removal of the frame assembly


80


the fan housing


43


can be preferably slid into place without the aid of tools. The wall of the mattress foundation


40


is open at the top so as to allow the fan housing


43


to be inserted and removed through the top of the foundation wall. The off/on switches


44




a,b


shall be inaccessible to infants or made tamperproof to prevent inadvertent stoppage of the fan. Options could include controls recessed under a latching cover or “lock-lever” type switches.




The heater


45


is preferably non-adjustable to maintain fixed air temperature at the low end of the infant's thermoneutral range of 23-27 degrees Centigrade. This is important to prevent accidental overheating which is known to contribute to SIDS while also preventing hypothermia when using unconditioned room air. A preferred embodiment will include an integral fixed temperature thermostat.




Preferably an inlet of the fan


49


will include a media filter


53


to reduce the possibility of the top surface perforations plugging with lint or dirt. Standard finger guards shall be used on the inlet and outlet of the media filter


53


. This arrangement will filter the air before it reaches the compartment where the fan is located.




Preferably the fan's electrical cord will have a tamperproof plug that fastens or locks securely to a wall outlet so as to prevent inadvertent stoppage of the fan


49


. The tamperproof plug might also include a transformer to convert to low voltage AC or DC current.





FIG. 10A

illustrates an exploded view of an alternative embodiment of the mattress assembly. The mattress foundation


140


is preferably molded as a single unit from tough-skinned, closed cell foam. A low voltage fan


149


is positioned in a sidewall of the mattress foundation


140


, and has a child resistant switch


148


for operation thereof. Slot


145


in the side of the mattress foundation


140


opposite from the fan


149


is provided to conduct the electrical wire from the fan


149


to the “back” of the mattress. Molded hooks


154


are provided at corners and midpoints of the side sections of the mattress foundation


140


to retain portions of the bedding


170


and thus hold the bedding


170


taut across the mattress assembly. A slot


147


runs around the periphery of the mattress foundation


140


, and may hold the cuff


174


of the bedding


170


. Raised shoulders


144


may be provided on either side of the fan


149


to move the cuff


174


of the bedding


170


away from the intake of the fan


149


, so as to avoid reducing the flow of air through the mattress assembly. The upper surface of the sidewalls of the mattress foundation


140


are provided with a plurality of fastener receptacles


152


.




A mattress inner core


150


, including a plurality of springs on a wire frame, preferably formed from non-corroding material or having a non-corrosive coating, thereon rests within the mattress foundation


140


. The mattress foundation


140


may be provided with rails, stops, or angle brackets for locating the inner core


150


in a desired position within the mattress foundation, as described hereinabove.




The top cover


160


is positioned on top of the inner spring


150


and is preferably attached to the mattress foundation


140


by passing fasteners


162


through peripheral holes


165


which correspond to the fastener receptacles


152


in the mattress foundation


140


. The top cover


160


is provided with a plurality of apertures


161


for allowing the free flow of air therethrough. The top cover


160


is preferably provided with cuttings


164


along either side in order to allow clearance for the attachment loops


172


of the bedding


170


be reach the hooks


154


positioned at midpoints along the side of the mattress foundation


140


. The cuttings may also be used as handles to facilitate easy removal of the top cover


160


from the mattress foundation


140


.




The bedding


170


is placed above the top cover


160


. Attachment loops


172


, preferably elasticized, are provided at the corners of the bedding


170


and midpoints along the sides thereof for looping over the hooks


154


of the mattress foundation


140


to attach the bedding


170


to the mattress assembly. The bedding


170


is preferably fabricated from a porous material to allow the passage of air therethrough. The bedding


170


is provided with a cuff


174


having elastic or a drawstring therein for attaching the bedding


170


to the bumper assembly


180


or the mattress foundation


140


.




A free standing bumper assembly


180


, preferably fabricated from the same type of material as the mattress assembly


140


may be provided to sit on top of the mattress foundation


140


. Slits


182


in the corners of the bumper assembly


180


are provided to tuck the cuff


174


of the bedding


170


and so reduce bunching of the cuff


174


at the corners.





FIG. 10B

illustrates a partial cross-section through the mattress assembly when the bumper pad


180


is in place. The cuff


174


of the bedding


170


is stretched over the top of the bedding


170


and held by the lip


184


. Air passing up through the top cover


160


may travel up between the cuff


174


and the bumper assembly


180


and pass through the material of the cuff


174


in a direction inwards from the bumper assembly


180


. This advantageously provides side ventilation without requiring that the bumper assembly


180


itself be ventilated. When the bumper assembly


180


is not in use, the cuff


174


of the bedding


170


may be inserted in the slot


147


on the periphery of the mattress foundation


140


, as is illustrated in FIG.


10


C. The embodiment illustrated in

FIGS. 10A-10C

may be readily taken disassembled to permit access to all components for cleaning or other maintenance.




Having read the foregoing description, it is to be understood, that even though numerous characteristics and advantages of various embodiments in accordance with the principles of the invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of the parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.



Claims
  • 1. A mattress comprising:a mattress foundation comprising a bottom wall and side walls, said bottom wall and said side walls are generally rigid and nonporous, and said bottom wall and said side walls defining a cavity that is open at the top thereof; a top cover detachably connected to said side walls and covering the top of the cavity to form, with said bottom wall and said side walls, a chamber; said top cover being nonporous except for apertures therethrough to allow airflow between the chamber and the exterior of the mattress foundation; a fan mounted to said mattress foundation for forcing air into the chamber and out the top cover through said apertures, wherein the size and spacing of the apertures and an air flow volume provided by the fan are chosen so as to effectively reduce accumulation of carbon dioxide in bedding on the top cover; a bumper assembly disposed on said side walls and extending upwardly therefrom above a level of said top cover, and bedding disposed over said top cover and disposed over said bumper assembly for directing air from the chamber to the bumper assembly, wherein the portion of said bedding disposed over said bumper assembly is porous whereby side ventilation is provided.
  • 2. A mattress in accordance with claim 1, wherein said apertures are spaced apart by less than 2 cm, said apertures have a diameter between {fraction (3/16)} inch and ⅛ inch, and said fan provides an air flow volume of between 25 and 170 cubic feet per minute.
  • 3. A mattress in accordance with claims 1, further comprising an inner core disposed within the chamber, said inner core being removably mounted within the chamber.
  • 4. A mattress in accordance with claim 1, further including bedding disposed over said top cover, and means associated with said side walls for maintaining the bedding in a taut condition.
  • 5. A mattress in accordance with claim 4, wherein said means comprises a bumper assembly disposed on said side walls.
  • 6. A mattress in accordance with claim 4, wherein said means comprises attachment fixture provided on said side walls.
  • 7. A mattress, comprising:a mattress foundation comprising a bottom wall and side walls, said bottom wall and said side walls are generally rigid and nonporous, and said bottom wall and said side walls defining a cavity that is open at the top thereof; a top cover detachably connected to said side walls and covering the top of the cavity to form, with said bottom wall and said side walls, a chamber; said top cover being nonporous except for apertures therethrough to allow airflow between the chamber and the exterior of the mattress foundation; a fan mounted to said mattress foundation for forcing air into the chamber and out the top cover through said apertures, wherein the size and spacing of the apertures and an air flow volume provided by the fan are chosen so as to effectively reduce accumulation of carbon dioxide in bedding on the top cover; a side assembly disposed on said side walls and extending upwardly therefrom above a level of said top cover, and means for directing air from the chamber to said side assembly whereby side ventilation is provided; and wherein said side assembly comprises a frame assembly and a bumper assembly, and said means for directing air comprises flow passages in said frame assembly and said bumper assembly.
  • 8. A mattress, comprising:a mattress foundation comprising a bottom wall and side walls, said bottom wall and said side walls are generally rigid and nonporous, and said bottom wall and said side walls defining a cavity that is open at the top thereof; a top cover detachably connected to said side walls and covering the top of the cavity to form, with said bottom wall and said side walls, a chamber; said top cover being nonporous except for apertures therethrough to allow airflow between the chamber and the exterior of the mattress foundation; a fan mounted to said mattress foundation for forcing air into the chamber and out the top cover through said apertures, wherein the size and spacing of the apertures and an air flow volume provided by the fan are chosen so as to effectively reduce accumulation of carbon dioxide in bedding on the top cover; and an inner core disposed within the chamber, said inner core being removably mounted within the chamber and extending above the level of said side walls.
  • 9. A crib assembly comprising:a mattress including: a mattress foundation having a bottom wall and side walls, said bottom wall and said side walls are generally rigid and nonporous, and said bottom wall and said side walls defining a cavity that is open at the top thereof; a top cover detachably connected to said side walls and covering the top of the cavity to form, with said bottom wall and said side walls, a chamber; said top cover is nonporous except for apertures therethrough to allow airflow between the chamber and the exterior of the mattress foundation; a fan mounted to said mattress foundation for forcing air into the chamber and out the top cover through said apertures, wherein the size and spacing of the apertures and an air flow volume provided by the fan are chosen so as to effectively reduce accumulation of carbon dioxide in bedding on the top cover; and a bumper assembly disposed on said side walls and extending upwardly therefrom above a level of said top cover, and bedding disposed over said top cover and disposed over said bumper assembly for directing air from the chamber to the bumper assembly, wherein the portion of said bedding disposed over said bumper assembly is porous whereby side ventilation is provided; and a crib supporting the mattress.
  • 10. A crib assembly in accordance with claim 9, wherein said apertures are spaced apart by less than 2 cm, said apertures have a diameter between {fraction (3/16)} inch and ⅛ inch, and said fan provides an air flow volume of between 25 and 170 cubic feet per minute.
  • 11. A crib assembly, comprising:a mattress including: a mattress foundation having a bottom wall and side walls, said bottom wall and said side walls are generally rigid and nonporous, and said bottom wall and said side walls defining a cavity that is open at the top thereof; a top cover detachably connected to said side walls and covering the top of the cavity to form, with said bottom wall and said side walls, a chamber; said top cover is nonporous except for apertures therethrough to allow airflow between the chamber and the exterior of the mattress foundation; a fan mounted to said mattress foundation for forcing air into the chamber and out the top cover through said apertures, wherein the size and spacing of the apertures and an air flow volume provided by the fan are chosen so as to effectively reduce accumulation of carbon dioxide in bedding on the top cover; a side assembly disposed on said side walls and extending upwardly therefrom above a level of said top cover, and means for directing air from the chamber to said side assembly whereby side ventilation is provided, wherein said side assembly comprises a frame assembly and a bumper assembly, and said means for directing air comprises flow passages in said frame assembly and said bumper assembly; and a crib supporting the mattress.
Parent Case Info

This application is a Continuation of application Ser. No. 08/782,249, filed Jan. 14, 1997 now U.S. Pat. No. 6,052,853 which is a Continuation in Part of application Ser. No. 08/481,767 filed Jun. 7, 1995 now abandoned, which application(s) are incorporated herein by reference.

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Continuations (1)
Number Date Country
Parent 08/782249 Jan 1997 US
Child 09/503422 US
Continuation in Parts (1)
Number Date Country
Parent 08/481767 Jun 1995 US
Child 08/782249 US