Abstract:
A fitted sheet that is particularly well suited for use on a small mattress such as a child&#39;s sleeping mattress has elastic on some, but less than all, of its bottom surface periphery. The portion without elastic is wider than the portion with elastic, and defines a pocket part. A first end of the mattress is inserted into the pocket part. The pocket part holds the mattress securely while the elasticized portion is stretched and slipped over the remainder of the mattress. The pocket part not only allows for easier insertion of the mattress into that part, but also serves as a visual index that allows the user to easily identify which part of the sheet goes on which part of the mattress.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    None. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to the field of sheets for mattresses. More particularly, this invention relates to the field of a fitted sheet for a child&#39;s sleeping mattress. 
         [0004]    2. Description of Related Art 
         [0005]    Fitted sheets having elastic strips sewn into the bottom in order to gather the bottom of the sheet inward thereby securely holding the sheet onto a mattress are well known. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is of a fitted sheet for a child&#39;s sleeping mattress. The sheet has an elasticized portion for the purpose of gathering the mattress inward in order to securely hold the sheet onto the mattress on which the sheet has been installed. However, only a portion of the bottom panel of the sheet is elasticized, defining an elasticized portion of the bottom panel of the sheet. The bottom panel also has an unelasticized portion which does not have an elastic strip on it. In an illustrative embodiment, the unelasticized portion extends inward toward the center of the bottom of the mattress farther than does the unelasticized portion. The unelasticized portion defines a pocket part of the sheet. 
         [0007]    In an illustrative embodiment the pocket part serves three functions. First, the pocket part can be more easily slipped over an edge of the mattress, and particularly over the edge of a child&#39;s sleeping mattress, than if the entire bottom panel of the sheet were elasticized. That is because the elastic in a fully elasticized fitted sheet tends to gather the entire bottom of the sheet inward thus closing off to some extent the opening between the top and bottom panels of the sheet into which a leading edge of the mattress is to be inserted. By eliminating the elastic from a portion of the bottom panel of the sheet, the unelasticized portion remains more open and freely accessible to the user, thus making it easier to insert the leading edge of the mattress into that unelasticized portion. 
         [0008]    Second, in an illustrative embodiment, the unelasticized portion of the sheet extends inwardly toward the center of the mattress&#39;s bottom more than does the average or even the maximum inward extend of the elasticized portion. The unelasticized portion thus defines a deeper pocket than the rest of the sheet. The deeper pocket securely holds the first-installed portion of the sheet, designated the leading portion of the sheet, over the respective portion of the mattress, designated the leading portion of the mattress, while the user slips the elasticized portion over the remainder of the mattress. The sheet thus overcomes a problem in prior art mattresses in which the user would place a leading portion of the sheet over a leading portion of the mattress, but while the user was stretching the remainder of the sheet over the bottom of the mattress, the leading portion could slip back off the mattress. 
         [0009]    Third, the unelasticized portion of the mattress serves as a visual index that helps the user easily identify which portion of the sheet goes on which portion of the mattress. This eliminates a disadvantage that was observed with prior art mattresses in which the sheet in its unstretched state was gathered by the elastic strip sewn into the sheet into a somewhat amorphous form in which it was not easy to see at a glance which part of the sheet should be placed over which part of the mattress. 
         [0010]    In one aspect therefore, the invention is of a fitted sheet, especially but not exclusively a fitted sheet for a child&#39;s sleeping mattress. The fitted sheet has a top panel having a periphery, a side extending around the top panel periphery, and a bottom panel extending from a bottom part of the side panel inward toward a center of the mattress. The bottom panel has a first and elasticized portion, the elasticized portion being drawn inward by an elastic member such as an elastic strip sewn or otherwise affixed around part of the inner edge of the bottom panel. The bottom panel also has an elongated and unelasticized portion that itself has no elastic drawing it inward. The unelasticized portion, together with an adjacent portion of the side and top panel, forms an unelasticized pocket capable of securely holding a side of the mattress while a user stretches the unelasticized portion over a bottom of the mattress. The pocket can extend to, or can extend past and thus over, at least one angled or curved side surface of the mattress. 
         [0011]    In another aspect, the invention is of a fitted sheet for a mattress such as but not necessarily a child&#39;s sleeping mattress, the fitted sheet having a top panel, a side, and a bottom panel. The bottom panel has an inner edge in which one or more elastic strips are incorporated along some, but not all, of the inner edge. The portion of the bottom panel inner edge that does not have an elastic member incorporated therein defines at least 10% of the bottom panel inner edge, and preferably at least 20% of the bottom panel inner edge, and extends inward toward a center of the bottom of the mattress a distance that is greater than the inward extent of the elasticized portion(s). 
         [0012]    In yet another aspect, the invention is of a method of placing a fitted sheet onto a mattress, the fitted sheet having both an elasticized portion and an unelasticized portion. The user optionally places a first side of the mattress on a surface with a second side of the mattress opposite the first side tilted upward to raise it above the surface. The user places an unelasticized and preferably extended pocket portion of the sheet over the second portion of the mattress. The pocket portion holds the second portion of the mattress securely while the user then stretches the elasticized portion over the remainder of the mattress. 
         [0013]    Exemplary embodiments of the invention will be further described below with reference to the drawings, in which like numbers refer to like parts. The drawing figures might not be to scale, and certain components may be shown in generalized or schematic form and identified by commercial designations in the interest of clarity and conciseness. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a top oblique view of a fitted sheet according to a first illustrative embodiment of the invention, the sheet being stretched to illustrate the form that it would taken when installed on a mattress. 
           [0015]      FIG. 2  is an oblique close-up view of fabric of the fitted sheet, illustrating breathability of the fabric from which the sheet is made. 
           [0016]      FIG. 3  is a side cutaway view of the fabric of  FIG. 2 . 
           [0017]      FIG. 4  is an oblique view showing the bottom of a mattress with the fitted sheet of  FIG. 1  partially installed thereon. 
           [0018]      FIG. 5  is an oblique view showing the mattress and fitted sheet of  FIG. 4 , with the fitted sheet fully installed onto the mattress. 
           [0019]      FIG. 6  is a bottom plan view showing the mattress and fitted sheet of  FIG. 5 . 
           [0020]      FIG. 7  is a top oblique view of a fitted sheet according to the invention for a rectangular mattress, the sheet having a pocket part along a long edge of the mattress, the sheet having been stretched to illustrate the form that it would taken when installed onto the mattress. 
           [0021]      FIG. 8  is a bottom oblique view of the sheet of  FIG. 7  installed on a rectangular mattress. 
           [0022]      FIG. 9  is a bottom oblique view of a fitted sheet according to the invention for a rectangular mattress, the sheet having a pocket part along a short edge of the mattress. 
           [0023]      FIG. 10  is a bottom oblique view of a fitted sheet according to the invention in which the sheet has elastic strips at corners of the sheet. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]      FIG. 1  is a top oblique view of a fitted sheet  10  according to a first illustrative embodiment of the invention. Fitted sheet  10  is stretched to illustrate the form that it would take when installed on a mattress, which is not shown. Fitted sheet  10  has a top panel  12  having a periphery  14  thereof. Sheet  10  further has a side  16  and a bottom panel  20  ( FIG. 4 ) extending from bottom part  18  of side  16 . Top panel  12 , side  16 , and bottom panel  20  can be separate panels that have been sewn or otherwise joined together, or they can be integrally formed, or they can be all formed from a single sheet of fabric that has been cut and sewn or otherwise joined together. It is anticipated that forming the sheet from a single sheet of fabric will be the most economical. The entire sheet  10  could even be formed of a single piece of fabric without any cutting thereof. The term “panel” or “panels” as used herein should therefore not be construed to mean that different panels were formed separately and then joined together. 
         [0025]    In a preferred embodiment the fabric of which sheet  10  including top panel  12  is formed is breathable, so that the sheet will allow flow of air therethrough and will thus be suitable for use on mattresses designed to increase air flow around the child and thus reduce incidences of Sudden Infant Death Syndrome (SIDS), such as the SIDS-preventative mattress disclosed in U.S. Pat. No. 7,752,691 to Bensoussan. 
         [0026]      FIG. 2  is an oblique close-up view of fabric  36  of the fitted sheet  10  illustrating breathability of fabric  36  from which sheet  10  is made. Fabric  36  may be made breathable by formation of small holes  38  therein. Alternatively, fibers of which sheet  12  is made could be loosely woven together leaving small openings between the fibers. A variety of breathable fabrics are known and would be suitable for use, as will be apparent to persons skilled in the art. However, it is not necessary to the invention that the fabric be breathable. 
         [0027]      FIG. 3  is a side cutaway view of the fabric  36  of  FIG. 2 , showing holes  38  that allow air to pass through the sheet. 
         [0028]      FIG. 4  is an oblique view showing the bottom of a mattress  40  with the fitted sheet  10  of  FIG. 1  partially installed thereon. Mattress  40  has side  42  and bottom  46 . This particular mattress includes an angled or curved side  44  because this particular mattress is a SIDS-preventative mattress such shown in U.S. Pat. No. 7,752,691. Mattress  40  also has an aperture  54  therethrough for air flow to the child, and a mesh  56  covering aperture  54 . Air can thus flow through aperture  54 , through mesh  56 , and through breathable fabric  12  to the child. 
         [0029]    Fitted sheet  10  includes a bottom panel  20  having an inner edge  28 . An elastic member or strip  34  is sewn or otherwise affixed to or incorporated within bottom panel  20  around a portion of inner edge  28 . Bottom panel  20  has an elasticized portion  22  which includes elastic strip  34 , and an unelasticized portion  24  which does not include elastic strip  34 . Inner edge  28  therefore has an elasticized portion  22  which includes some or most, but not all, of inner edge  28  of the bottom of fitted sheet  10 . Unelasticized portion  24  defines a pocket or pocket portion  26  of fitted sheet  10 . As shown more clearly in  FIG. 6 , in this embodiment the unelasticized portion  24  is wider than the elasticized portions  22 , that is, an inward extent  25  of the unelasticized portion  24  toward center  41  of bottom  46  of mattress  40  is greater than an inward extent  23  of elasticized portion  22 . In an illustrative embodiment, elasticized portion  22  of bottom panel  20  includes at least a majority of the surface area of bottom panel  20 , and the elasticized portion includes 10-45% of the surface area of bottom panel  20 . In one possible embodiment, unelasticized portion  24  extends inwardy by at least 50% more than an average inward extent of elasticized portion  22 . Unelasticized portion  24  may extend inward by at least 50% more than a minimum inward extent of elasticized portion  22 , and may extend inward by at least 50% more than a maximum inward extent of elasticized portion  22  not including the parts of elasticized portion  22  that are immediately adjacent to unelasticized portion  24 . In a contemplated embodiment, unelasticized portion  24  extends inward by more than twice an average inward extent of the elasticized portion(s). As shown in  FIG. 5 , the inward extent of unelasticized portion  24  extends past an edge  55  of aperture  54 , whereas none of the elasticized portion  22  extends past aperture  54 . 
         [0030]    In the embodiment shown, unelasticized portion  30  of inner edge  28  defines at least 10% by distance of inner edge  28 , and more preferably at least 20% by distance of inner edge  28 . Further in the embodiment, the unelasticized portion covers approximately one full side, or more than one full side, of a multi-sided mattress such as multi-sided mattress  40  shown. 
         [0031]    Sheet  10  may optionally also have a visual index  70  on pocket part  26  that facilities easy identification of the part of the sheet that is to be slipped onto the mattress first. As shown, visual index  70  is a printed bar on pocket part  26  near inner edge  28 . The index could take any visually identifiable form. 
         [0032]    The mattress has a first end  50 , and a second end  52  opposite the first end. Sheet  10  is shown partially installed on second end  52 . Second end  52  on which fitted sheet  10  is first placed defines what will be referred to herein as a leading end  52  of mattress  40 , and the portion of fitted sheet which is first placed onto leading end  52  of mattress  40  will be referred to herein as a leading portion of fitted sheet  10 . In the figure, pocket  26  has been placed over leading end  52  of mattress  40 . Once the leading end  52  has been placed within pocket  26 , the elasticized portions  22  of the sheet can be stretched and fitted over the other ends of the mattress without pocket  26  slipping off, as had been a problem sometimes observed with prior art fully elasticized fitted sheets. 
         [0033]      FIG. 5  is an oblique view showing mattress  40  and fitted sheet  10  of  FIG. 4 , with fitted sheet  10  fully installed on mattress  40 . Elastic strip  34  draws the elasticized portion  22  of bottom panel  20  including its inner edge  28  inwardly to securely hold fitted sheet  10  on the mattress. While unelasticized portion  24  itself includes no elastic strip drawing that portion inward, elastic strip  34  on elasticized portion  22  serves to draw bottom panel  20  including its inner edge  28  overall inward, and thus adequately performs the function of keeping fitted sheet  10  securely on mattress  40 . In this embodiment, unelasticized pocket  26  covers one side of mattress  40 , and extends along that side of the mattress to, or even over and past, at least one angled or curved portion  44  of mattress  40  at either side of unelasticized portion  24 . 
         [0034]      FIG. 6  is a bottom plan view showing the mattress and fitted sheet of  FIG. 5 . 
         [0035]    It is not necessary for elastic strip  34  to extend all the way around inner edge  28  except for the pocket part  26 , and thus extend from a first end of pocket part  26  to a second and opposite end of pocket part  26 . Alternatively, elastic strip(s) could extend only at and around sheet corners  60  and  62 , or only at and around corners  60 ,  62 ,  64 , and  66 , or other portions of inner edge  28  sufficient to hold fitted sheet  10  on mattress  40 , and thus the elastic strip(s) do not extend all the way to both ends of pocket part  26 . 
         [0036]      FIG. 7  is a top oblique view of a fitted sheet  110  according to the invention for a rectangular mattress, the sheet having a pocket part along a long edge of the mattress, the sheet having been stretched to illustrate the form that it would taken when installed onto the mattress.  FIG. 8  is a bottom oblique view of the sheet  110  of  FIG. 7  installed on such a mattress  140 . In this embodiment the unelasticized pocket part  126  defined by extended unelasticized portion  124  of fitted sheet  110  is located along a longer side of the rectangular mattress. Unelasticized portion  130  of the inner edge defined by the absence of elastic strip  134  incorporated therein extends along a longer edge of the rectangular mattress. Elasticized portion  132  of the inner edge defined by the presence of elastic strip  134  is incorporated into the two shorter ends of rectangular mattress  140  and the long end that is opposite the end covered by pocket  126 . In the embodiment as shown, the mattress has an aperture  154  in it, although the invention is not limited to use with a mattress having an aperture therein. 
         [0037]      FIG. 9  is a bottom oblique view of a fitted sheet  210  according to the invention for a rectangular mattress, the sheet  210  having a pocket part  226  defined by unelasticized part  224  of bottom panel  220  along a shorter edge of the mattress. Elastic strip  234  defining an elasticized portion  222  of bottom panel  220  is incorporated along the inner edge of bottom panel  220  along the two long sides of the mattress and along the short side that is opposite the pocket part  226 . In the embodiment as shown, the mattress has no aperture in it. 
         [0038]      FIG. 10  is a bottom oblique view of a fitted sheet according to the invention in which the sheet  310  has elastic strips  334 ,  335  at two adjacent corners  360 ,  362  of the sheet that are opposite the pocket part  326 . In this embodiment, there is no elastic strip that extends as far around the mattress as does elastic strip  234  in the embodiment of  FIG. 9 . Instead, elastic is sewn to the sheet only at corners  360 ,  362  located on a first end of the sheet, but not in corners  364 ,  366  that are located on the opposite end of the sheet. Alternatively, the elastic strip could comprise a single elastic strip that extends at least around corners  360  and  362 , and extends along some but less than all of the longer sides of the mattress. 
         [0039]    A method of using and installing the sheet is as follows. The user positions mattress  40  so that one end  50  is resting on a surface and opposite end  52  is raised above the surface. The user inserts the unelasticized pocket part  26  of fitted sheet  10  over end  52  of the mattress that is raised above the surface, and then stretches the elastic strip  34  in elasticized portion  22  over the remaining portion of mattress  40  including mattress end  50  that is opposite end  52 . 
         [0040]    All features disclosed in the specification, including the claims, abstract, and drawings, and all the steps in any method or process disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. Each feature disclosed in the specification, including the claims, abstract, and drawings, can be replaced by alternative features serving the same, equivalent, or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 
         [0041]    It will be appreciated that the term “present invention” as used herein should not be construed to mean that only a single invention having a single essential element or group of elements is presented. Although the present invention has thus been described in detail with regard to the preferred embodiments and drawings thereof, it should be apparent to those skilled in the art that various adaptations and modifications of the present invention may be accomplished without departing from the spirit and the scope of the invention. Accordingly, it is to be understood that the detailed description and the accompanying drawings as set forth hereinabove are not intended to limit the breadth of the present invention, which should be inferred only from the following claims and their appropriately construed legal equivalents.