Abstract:
A mattress system constructed of synthetic foam is described especially for use as a maternity mattress. The mattress system has a main mattress portion with a specifically shaped central opening through the center thereof. At least two modular plugs have both a top and bottom that is generally flat but are in some embodiments textured and the curved peripheries thereof are smooth with a curvature to mate with the central opening of the main mattress portion. The modular plugs may be of different thicknesses and can be selectively removed and positioned to increase the depth of the opening for receipt of a woman&#39;s growing abdomen during pregnancy.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Application No. 60/217,792, filed Jul. 12, 2000. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention generally relates to a mattress for a bed. More specifically, the present invention relates to a mattress having provision for accommodating the abdomen of a pregnant woman. Still further, the present invention relates to a mattress having a central opening with modular plugs for altering the depth of the central opening, which is capable of accommodating the abdomen of a pregnant woman.  
           [0003]    Conventional mattresses are known and maternity mattresses per se are not new. U.S. Pat. No. 4,021,872, incorporated fully herein by reference, discloses a maternity mattress with a modifiable cavity for supporting the enlarged abdomen of a pregnant woman. The mattress comprises resilient disk-like members as filler means removably received in a circular cavity. The disk-like members, at least two concave mattress sections, can be selectively removed to alter the size of the circular cavity.  
           [0004]    U.S. Pat. No. 4,051,566, incorporated fully herein by reference, discloses a mattress system with a modifiable cavity for supporting the abdomen of a pregnant woman. The mattress system comprises a mechanical undercarriage capable of raising and lowering a removable pad or pads through openings in both the mattress and box spring to generate a cavity for supporting a pregnant woman&#39;s enlarged abdomen.  
           [0005]    While useful for its purpose, the &#39;872 mattress utilizes a circular shaped cavity which does not conform to the more teardrop shape of a pregnant woman&#39;s growing abdomen. As a result, the cavity fails to provide proper support for the patient during use of the mattress. The &#39;566 mattress system requires a complex mechanical system for raising and lowering the removable pads, as well as, openings completely through both the mattress and the box spring. This results in increased cost and complexity of the system in order to achieve a maternity mattress with an adjustable cavity. Additionally, the &#39;872 and the &#39;566 mattresses are mattress replacements and not supplements for use with other mattresses and neither provide any surface treatment for increased comfort of the patient.  
           [0006]    It is, therefore, desirable to provide a simple, cost effective mattress supplement with a generally teardrop shaped central opening and two modular plugs removably received therein for selectively altering the depth of the central opening during the term of the pregnancy, where the upper and lower surfaces of the main mattress portion and the exterior surfaces of the modular plugs have a specific surface treatment to enhance the patient&#39;s comfort during use of the mattress.  
         SUMMARY OF THE INVENTION  
         [0007]    The present invention recognizes and addresses various of the foregoing limitations and drawbacks, and others, concerning the cost, comfort, and adjustability of a maternity mattress. Therefore, the present invention provides a new maternity mattress with a generally teardrop shaped central opening and two modular plugs removably received therein for selectively altering the depth of the central opening during the term of the pregnancy. In addition, both the upper and lower surfaces of the main mattress portion and the exterior surfaces of the modular plugs have a specific surface treatment to enhance the comfort level of the patient while utilizing the mattress.  
           [0008]    It is a principle object of the subject invention to provide a mattress system for use during a term of pregnancy. More particularly, it is a principle object of the present invention to provide a maternity mattress system that allows women to more comfortably sleep during the period of their pregnancy.  
           [0009]    Another more particular object of the present invention is to provide a maternity mattress system capable of adequately supporting the enlarged abdomen of a pregnant woman while allowing her to rest in a prone position. In such context, it is an object of the present invention to provide a maternity mattress system with a central opening, which can be selectively altered in depth as desired for changing comfort by the patient over the term of a pregnancy.  
           [0010]    It is a more general object of the present invention to provide a maternity mattress system, which has a specific surface treatment for increasing the comfort level of the patient. In such context, it is an object of the present invention to provide a foam maternity mattress system with a generally flat surface comprised of numerous discrete upstanding projections being independently compressible with voids between the projections.  
           [0011]    It is still a further object of the present invention to provide a foam maternity mattress system with a specific surface treatment which has a central opening through the main mattress portion for receipt of at least two selectively removable modular plugs so as to allow for alteration of the depth of the central opening wherein the growing abdomen of a pregnant woman can be properly and comfortably supported while the woman rests in a prone position.  
           [0012]    Additional objects and advantages of the invention are set forth in, or will be apparent to those of ordinary skill in the art from, the detailed description as follows. Also, it should be further appreciated that modifications and variations to the specifically illustrated and discussed features and materials hereof may be practiced in various embodiments and uses of this invention without departing from the spirit and scope thereof, by virtue of present reference thereto. Such variations may include, but are not limited to, substitutions of the equivalent means, features, and materials for those shown or discussed, and the functional or positional reversal of various parts, features, or the like.  
           [0013]    Still further, it is to be understood that different embodiments, as well as different presently preferred embodiments, of this invention, may include various combinations or configurations of presently disclosed features, elements, or their equivalents (including combinations of features or configurations thereof not expressly shown in the figures or stated in the detailed description).  
           [0014]    These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the principles of the invention.  
           [0015]    One exemplary embodiment of the present invention includes a mattress system comprised of any of the numerous well-known synthetic foam materials. Such mattress system includes a main mattress portion sized for use by an individual with a central opening therein. Disposed within such main mattress portion central opening may be at least two selectively removable modular plugs whose curved peripheries may be smooth and have a curvature to mate with such main mattress portion&#39;s central opening.  
           [0016]    The upper surface of such mattress system, including such inserted modular plugs, may have a surface treatment, which generates a uniform series of upstanding projections or promontories with a generally flat apex surface. Each individual promontory may be surrounded by voids, which allow for their individual compression. One of ordinary skill in the art will recognize that any suitable surface treatment, including no surface treatment at all, may be used with the present invention and either the upper or lower surfaces or both can be given such surface treatment.  
           [0017]    Another exemplary embodiment of the present invention includes a mattress system comprised of any of the well-known synthetic foam materials. Such mattress system includes a main mattress portion sized for more than one person with an opening located centrally within one-half of such mattress portion. Such main mattress portion allows for the use of the mattress system on larger beds where the presence of a smaller mattress supplement could be awkward. Disposed within such main mattress portion central opening may be at least two selectively removable modular plugs whose curved peripheries may be smooth and have a curvature to mate with the main mattress portion&#39;s central opening.  
           [0018]    The upper and lower surfaces of such mattress system, including such inserted modular plug&#39;s external surfaces (excluding the peripheries thereof), may have a surface treatment which generates a uniform series of upstanding projections or promontories with a generally flat apex surface. Each individual promontory may be surrounded by voids which allow for their individual compression.  
           [0019]    In use, any embodiment of the present invention allows a patient (i.e., a pregnant woman) to selectively remove one or all of such modular plugs to alter the depth of such central opening to more comfortably accommodate and support her growing abdomen while she is resting in a prone position and throughout the term of her pregnancy. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]    A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:  
         [0021]    [0021]FIG. 1 is a top plan view of an embodiment of the present invention illustrating the central opening within the mattress of the modular maternity mattress system with the two modular plugs removed therefrom, such view in some embodiments being the identical view as the bottom plan view thereof;  
         [0022]    [0022]FIG. 2 is a right-side plan view of the embodiment of the present invention shown in FIG. 1, such view being the identical view as the rightside plan view thereof;  
         [0023]    [0023]FIG. 3 is a perspective view of the embodiment of the present invention shown in FIG. 1, with the two modular plugs positioned in exploded view relative to the mattress central opening therefore;  
         [0024]    [0024]FIG. 4 is a front plan view of the embodiment of the present invention shown in FIG. 1, with the two modular plugs of present FIG. 3 received in the central opening thereof; and  
         [0025]    [0025]FIG. 5 is a partial cross-sectional view taken along line A-A of FIG. 3, illustrating an alternative embodiment of the present invention including a textured surface for both the main mattress portion and/or the modular plugs therein comprising individually compressible promontories with generally flat apex surfaces.  
         [0026]    Repeat use of reference characters throughout the present specification and appended drawings is intended to represent the same or analogous features or elements of the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]    Reference will now be made in detail to presently preferred embodiments of the invention, examples of which are fully represented in the accompanying drawings. Such examples are provided by way of an explanation of the invention, not limitation thereof. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention, without departing from the spirit and scope thereof. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Still further, variations in selection of materials and/or characteristics may be practiced, to satisfy particular desired user criteria. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the present features and their equivalents.  
         [0028]    As disclosed above, the present invention is particularly concerned with a simple, cost effective maternity mattress system with a generally teardrop shaped central opening and two modular plugs removably received therein for selectively altering the depth of the central opening during the term of the pregnancy, where the upper and lower surfaces of the main mattress portion and the exterior surfaces of the modular plugs may have a specific surface treatment to enhance the patient&#39;s comfort during use of the mattress. The functional aspects of the present invention are derived from but not inherent to the design characteristics filed in commonly owned U.S. Design Patent No. 411,933, incorporated fully herein by reference. FIG. 1 depicts the maternity mattress system  10  comprising a foam main mattress portion  12  with a central opening  14  of predetermined shape therein. In particular, the upper surface  16  of the main mattress portion  12  is shown.  
         [0029]    One of ordinary skill in the art may recognize that any of the numerous well-known synthetic foam materials may be used for the present invention. Due to the delicate nature of the support being provided, however, certain support characteristics as defined by the foam material chosen are preferred.  
         [0030]    One such support characteristic is the density (in pounds per cubic foot) of the foam selected. It is broadly preferred that the foam have a density in a range of from about 1.0 to about 2.0 pounds per cubic foot. It is more preferred that the foam utilized in the present invention have a foam density of 1.3±0.05 pounds per cubic foot to achieve a generally non-crushable surface capable of providing support for the user (i.e., a pregnant woman) without being considered uncomfortable.  
         [0031]    Another support characteristic of the foam material selected is the indentation load deflection (ILD) characteristic. The ILD of a material may be defined as the number of pounds of pressure required to push a fifty square inch circular plate into a sample of the material a given percentage deflection thereof. For example, a twenty-five percent ILD of thirty pounds would mean that thirty pounds of pressure is required to push a fifty inch circular plate into a four inch thick piece of the selected foam material a distance of one inch (i.e., twenty-five percent of the original unloaded thickness). It is desired that the foam utilized in the present invention have a twenty-five percent ILD of between about twenty-seven and about thirty-three pounds to achieve a sufficiently sturdy supportive surface without being considered uncomfortable. Some embodiments may include variations to such range.  
         [0032]    Similarly, one of ordinary skill in the art may recognize that various shapes may be used for such central opening  14  within such main mattress portion  12 . It is preferred, however, that a teardrop shaped opening  14  as illustrated be used. Such a teardrop shape conforms better because it mimics the shape of a pregnant woman&#39;s abdomen. This allows such central opening  14  and main mattress portion  12  to provide the support necessary to result in a more comfortable resting position throughout the term of the pregnancy for the patient.  
         [0033]    [0033]FIG. 2 depicts the left side plan view of a preferred embodiment of the present invention. In particular, FIG. 2 illustrates an embodiment where no surface treatment has been applied to either the upper surface  16  or the lower surface of the main mattress portion  12  of the mattress system  10 . U.S. Pat. Nos. 4,603,445 and 4,686,725, incorporated fully herein by reference, show various surface treatments on either the upper or lower surface or on both referenced surfaces of a mattress having individually compressible promontories as will be discussed further hereafter.  
         [0034]    The preferred mattress system  10  is further shown in FIGS. 3 and 4. FIG. 3 illustrates a partially exploded view depicting the main mattress portion  12  with its central opening  14  therein and at least two modular plugs  20  and  22  for removable receipt in such central opening  14  as indicated. FIG. 4 illustrates the mattress system  10  wherein the modular plugs  20  and  22  are disposed within the central opening  14  in said main mattress portion  12 .  
         [0035]    Such modular plugs  20  and  22  are preferably of differing thicknesses to allow for variable combinations and the resulting variation in depth of such central opening  14  needed to allow use of such mattress system  10  throughout the full term of the pregnancy. For example, a patient may begin using such mattress system  10  when she learns that she is pregnant. As her abdomen begins to grow during her pregnancy, she may first remove modular plug  20  (the less thick of the two plugs) for greater comfort during sleep. As her abdomen continues to grow, she may next remove modular plug  22  and replace it with modular plug  20  allowing for even greater depth of the central opening  14  while retaining sufficient support for her abdomen.  
         [0036]    The mattress system  10  as depicted in FIGS. 1, 3, and  4  is preferably sized for a single individuals use. Generally, as one specific example, a main mattress portion  12  thirty-four inches in width, seventyfive inches in length and approximately four and one-half inches thick would be sufficient to support a pregnant woman of two hundred pounds or more. One of ordinary skill in the art may recognize that alternative embodiments could be of any size including a mattress system  10  sufficient to support multiple patients or a patient and another person. For example, in such instance, the mattress could be supplied as an example with an opening centrally located on one lateral side of the mattress. If the mattress were supplied with promontories on one side and none on the opposing side, then reversal of the mattress would result in changing the type of surface for user support while reversing the lateral position of the opening.  
         [0037]    [0037]FIG. 5 illustrates just one of several possible surface treatments for use with the preferred embodiment of the present invention. In particular, the surface treatment shown includes a textured surface for both the main mattress portion  12  and the modular plug&#39;s external surfaces  24  and  25 . Such textured surface includes individually compressible promontories  27  with generally flat apex surfaces  26 . Generally, in accordance with the subject invention, the promontories  27  are to a degree independent of each other, for improved resilient support. Each promontory  27  in this particular example is surrounded by voids  28  which separate it from the surrounding foam material to allow for individual compression. In another embodiment, the promontories (i.e., support projections) joined adjacent bases and/or curved or rounded top surfaces, such as the promontories of U.S. Pat. No. 4,686,725. The curved peripheries of the modular plugs  20  and  22  would preferably not have the surface texture but may have a smooth contour and have a curvature to mate with the central opening  14 . One of ordinary skill in the art may recognize that such a surface treatment need not be present on both sides of the main mattress portion  12  or the modular plugs  20  and  22  but may be present on only one side of the main mattress portion  12  and/or one side of the modular plugs  20  and  22  or any combination thereof.  
         [0038]    Although a preferred embodiment of the invention has been described using specific terms and devices, such description is for illustrative purposes only. The words used are words of description rather than of limitation. It is to be understood that changes and variations may be made by those of ordinary skill in the art without departing from the spirit or the scope of the present invention. In addition, it should be understood that aspects of various other embodiments may be interchanged both in whole or in part. Therefore, the spirit and scope of the present invention should not be limited to the description of the preferred versions contained herein.