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:
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. 
    
    
     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  &amp;  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&#39;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&#39;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.