Patent Abstract:
This invention is directed to a mattress assembly for use in a sofa sleeper. The mattress assembly has a first mattress that has an inner-spring construction. Disposed above the first mattress is a second mattress that has an air bladder construction. The air bladder of the second mattress has a valve, which is located adjacent the head end of the mattress. The valve is adapted to selectively allow air into and out of the air bladder. The mattress assembly thus provides the combination of an innerspring mattress with an air mattress. The location of the valve allows the air mattress portion to be deflated properly and allows convenient access to the valve for inflation or air pressure adjustment purposes.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Serial No. 60/282,240, filed Apr. 6, 2001. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     This invention relates generally to a mattress system, and, more particularly, to a mattress system that combines the benefits of a traditional coil mattress with the additional comfort of an air mattress for use in a sofa sleeper. 
     It is well known that the mattresses provided within a sofa sleeper can be uncomfortable to those sleeping thereon. This uncomfortability is, in part, a result of the space constraints existing within a sofa sleeper. In other words, the available space within a sofa sleeper for the mattress when the mattress is in a stowed condition necessitates a mattress that is relatively thin. A typical sofa sleeper mattress is used that has an inner spring coil construction. Typically, these mattresses are approximately four inches thick. When a mattress is used that is of this thickness, the person sleeping on the mattress can often feel the support structure for the mattress, such as the steel frame for the sofa sleeper. It would, therefore, be desirable to manufacture a mattress for a sofa sleeper that increased the comfort of the individual sleeping thereon. However, because it is used within a sofa sleeper, the mattress must fit within a typically dimensioned sofa sleeper unit. 
     Traditional sofa sleepers are designed with a folding frame mechanism that operates to stow the mattress when the unit is used as a sofa, and that is used to deploy and support the mattress when the unit is used as a sleeping surface. When the user of the bed wishes to stow the mattress, the foot portion of the bed is folded upwardly over the mattress. In this position the foot portion of the mattress is folded over the middle portion of the mattress. The end of the mattress assembly is then lifted upwardly, so that the folded-over portion of the foot as well as the middle part of the mattress is lifted. In the lifted position, the mattress assembly is moved towards the back of the sofa sleeper. The back of the mattress assembly is received within the back of the sofa frame, and the foot portion and middle portion of the mattress form the support surface for the cushions of the sofa. 
     In a sofa sleeper having an air mattress, it is important to properly deflate the air bladder prior to stowing the mattress within the sofa sleeper. Failure to properly deflate the air bladder will cause problems in stowage, such as a failure to completely stow the mattress assembly. In addition, the improper deflation of the air bladder can place additional and unwanted stress upon the support frame. 
     It is therefore an object of the present invention to provide a sofa sleeper of increased comfort through the use of a combination mattress assembly that can be easily and efficiently stored when not in use. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention is directed to a mattress assembly for use in a sofa sleeper. The mattress assembly has a first mattress that has an inner-spring construction. Disposed above the first mattress is a second mattress that has an air bladder construction. The air bladder of the second mattress has a valve, which is located adjacent the head end of the mattress. The valve is adapted to selectively allow air into and out of the air bladder. The mattress assembly thus provides the combination of an innerspring mattress with an air mattress. The location of the valve allows the air mattress portion to be deflated properly and allows convenient access to the valve for inflation or air pressure adjustment purposes. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     These and other objectives and advantages of the present invention will be more readily apparent from the following detailed description of the drawings of the preferred embodiment of the invention that are herein incorporated by reference and in which: 
     FIG. 1 is a perspective view of a sofa sleeper according to the present invention, with the mattress in the deployed position; 
     FIG. 2 is a top plan view of the sofa sleeper of FIG. 1; 
     FIG. 3 is an exploded view of the mattress assembly of the sofa sleeper of FIG. 1; 
     FIG. 4 is an enlarged view of the encircled region  4  of FIG. 3, showing the valve in the open position; 
     FIG. 5 is a view similar to FIG. 4, showing the valve in the closed position; and 
     FIG. 6 is a view similar to FIGS. 4 and 5, showing an inflating pump in place over the valve. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With initial reference to FIG. 1, a sofa sleeper according the principles of the present invention is designated generally with the reference numeral  10 . Throughout this specification, the term sofa sleeper is also intended to encompass love seats and other smaller units, such as snugglers. Sofa sleeper  10  is constructed with a sofa frame  12 , which includes a pair of arms  14  and a back  16 . FIG. 1 illustrates the sofa sleeper  10  in the deployed position, useful as a sleeping surface. As best seen in FIGS. 1 and 3, sofa sleeper  10  has a mattress frame mechanism  18  coupled thereto. Frame  18  is any one of a number of existing frames available and known to those of skill in the art. Frame  18  is attached to the sofa frame  12  and operates to move a mattress assembly  20  from the deployed position shown in FIG. 1 to the stored position when sofa sleeper  10  is used a sofa. 
     As best seen in FIG. 3, the mattress assembly  20  rests upon a support surface  22  provided as part of frame  18 . As an example, support surface  22  can be provided by a number of springs attached to frame  18  and to a resilient fabric material, as is known to those of skill in the art. Mattress assembly  20  includes a lower mattress  24  that is comparable to the mattresses used within sofa sleepers in the past. As such, mattress  24  is typically about four inches in thickness. To provide support, a number of coil springs  26  are used. This type of construction is referred to as an innerspring mattress. As stated above, when mattress  24  is used alone, the mattress is readily stowed within sofa sleeper  10 , but does not provide the desired level of comfort. To increase the comfort of the mattress assembly, additional components are incorporated. 
     With continued reference to FIG. 3, the mattress assembly  20  includes an inner panel  28 . The inner panel  28  serves as a divider between the lower mattress  24  and an air bladder  30 . A cover border  32  is attached on its lower edge  34  to the inner panel  28  and the lower mattress  24 . Cover border  32  has a zipper attached on its upper edge  38  that is used to removably couple a top panel cover  40  to the border  32 . As viewed in FIG. 2, the zipper preferably terminates in an upper corner of the mattress assembly, so that an upper corner of the bladder  30  can easily be exposed. As can be understood, the inner panel  28 , cover border  32  and top panel cover  40  form a pocket to receive the bladder  30 . 
     Air bladder  30  is thus received within the pocket formed by panel  28 , cover border  32  and top panel cover  40 . The zipper  36  is moved to a closed position when the bladder is completely inflated, but can be opened either partially or fully, as necessary, as is more fully described below. Air bladder  30  is preferably made from a durable, air impermeable material, such as vinyl. The vinyl side panels  42  and bottom panels  44  are typically exposed. A top surface  46  is coupled to the top of air bladder  30  and is preferably made from a fabric or material, such as a cotton surface or other flocked material. The top surface  46  will thus reduce the potential for noise when sleeping thereon, such as may be experienced if the top were made of a smooth vinyl material. Additionally, the air bladder is constructed with a series of horizontally extending indentations  48 , formed in the top surface  46 . Extending below each indentation  48  is a baffle element located within the air bladder. The baffles operate to properly route the air through the bladder  30 , as would be understood by those of skill in the art. 
     A valve  50  is integrally formed or coupled with the bladder  30  in the upper corner thereof, as viewed in the figures. Turning to FIGS. 4-6, the valve  50  is seen in more detail. Valve  50  as a large mouth  52  that allows air to escape from bladder  30  quickly when the valve is in an open position. A top  54  is hinged to and snaps over mouth  52  to close the valve  50 . The top  54  is thus moveable between the open position shown in FIG. 4 to the closed position shown in FIG.  5 . The top  54  may additionally be provided with a smaller valve assembly, not shown, which can be used to release small amounts of air. This smaller valve assembly thus provides some adjustability to the firmness of the bladder  30 . As shown in FIG. 5, the top  54  may also have a removable cap  56  that prevents the smaller valve assembly from inadvertent deflation of the bladder. The top  54  is also formed to accommodate an inflating pump  58  as shown in FIG.  6 . Preferably, pump  58  and top  54  are made to mate with one another when the cap  56  is removed, such that when pump  58  is placed on top  54  and is engaged, the pump will activate to fill bladder  30 . Pump  56  is illustrated as having a power cord  60  that supplies power to the pump. Other power supplies could also be used, such as batteries. 
     To place the sofa sleeper  10  in a position for sleeping, the cushions of the sofa are removed and the frame  18  is pulled from the sofa cavity and unfolded into the position shown in FIG.  3 . In this position, the bladder  30  is still in the deflated condition. The zipper  36  is then used to expose valve  50 , as shown in FIGS. 1 and 2. The cap  56  is removed from the top  54  and the pump  58  is engaged with the top, as shown in FIG.  6 . The engagement of the pump with the top causes the pump to fill the bladder  30  with air. When the bladder  30  is filled with an amount of air suitable to the comfort needs of the user, the pump  58  is disengaged from top  54  and the cap  56  is replaced on top  54 . The top panel cover is then re-zipped to hide the valve  50 . The sofa sleeper in this position is ready for sleeping. The additional support provided by the bladder  30  within the mattress assembly  20  increases the overall comfort of those sleeping upon the sofa sleeper. Moreover, the top surface of the bladder  30  reduces any noise associated with the material of the bladder. 
     When the mattress assembly  20  is to be stowed within sofa sleeper  10 , the zipper is used to expose valve  50 . The top  54  of the valve is then opened, allowing air to escape from the bladder  30  through mouth  52 . The large opening allows air to rapidly escape from the bladder. The removal of air is furthered by the positioning of the valve and the operation of the frame  18 . More specifically, after valve  50  is opened, the foot end of frame  18  is folded upwardly and inwardly, as with a traditional sofa sleeper mechanism. The foot end is folded over, so that the foot end portion of the mattress assembly rests on the middle portion of the mattress assembly. This folding operation results in air being “squeezed out” of the bladder  30 , pushing the air towards valve  50  and out mouth  52 . The frame  18  is then moved into the stowed position, which pushes any remaining air out of the bladder  30 . The positioning of valve  50  therefore reduces the likelihood that any significant amount of air will remain within bladder  30  when the mattress assembly  20  is moved to a stowed position. Therefore, the likelihood that the mattress assembly will not stow properly, or that any damage will be done to mattress frame  18  is also reduced. If the valve were placed in an area other than the head end of the bed, such as at the foot of the bed, the likelihood of improper deflation increases. 
     Should the bladder ever need replacement or repair, the zipper  36  allows full and easy access to the bladder without damaging the mattress assembly in any way. Zipper  36  also provides easy access to the valve  50  for any necessary operations, such as opening and closing the valve and making pressure adjustments to the air bladder  50 . 
     The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its scope. 
     From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects set forth above, together with other advantages which are obvious and inherent to the system and method. It will be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations. This is contemplated and with the scope of the claims.

Technology Classification (CPC): 0