Abstract:
The present technology provides an encasement comprising a fabric cover formed of bed bug impervious fabric. The encasement comprises an opening with a zipper mechanism disposed therein and operable to close the opening. The encasement also comprises a barrier attached to the fabric cover, extending along and opposite the zipper tracks. The encasement also comprises a channel between the barrier and said zipper tracks that receives a portion of the zipper head and becomes an enclosed channel when said zipper tracks are mated together. The channel has a confined space of a size to thwart bug movement along the channel.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application makes reference to, and claims priority to, U.S. patent application Ser. No. 13/252,337 (“the &#39;337 application”), filed Oct. 4, 2011 and titled “Method Of Preventing Bed Bugs From Escaping A Mattress Encasement Via A Zipper Opening.” The &#39;337 application claims priority to U.S. patent application Ser. No. 12/703,900 (“the &#39;900 application), filed Feb. 11, 2010 and titled “Mattress Encasement For Preventing Bed Bug Escapement Via A Zipper Opening.” The &#39;900 application claims priority to U.S. patent application Ser. No. 12/498,863 (“the &#39;863 application), filed Jul. 7, 2009 and titled “Mattress Encasement For Preventing Bed Bug Escapement Via A Zipper Opening.” The &#39;863 application claims priority to U.S. patent application Ser. No. 12/255,913 (“the &#39;913 application), filed Oct. 22, 2008 and titled “Mattress Encasement For Preventing Bed Bug Escapement Via A Zipper Opening.” The &#39;913 application claims priority to U.S. patent application Ser. No. 11/756,249 (“the &#39;249 application”), filed May 31, 2007 and titled “Mattress Encasement For Preventing Bed Bug Escapement Via A Zipper Opening,” and which issued on Jun. 30, 2009 as U.S. Pat. No. 7,552,489 (“the &#39;489 patent”). The &#39;249 application and the &#39;489 patent claim priority to U.S. Provisional Application No. 60/895,011 (“the &#39;011 provisional), filed Mar. 15, 2007 and titled “Mattress Encasement For Preventing Bed Bug Escapement Via A Zipper Opening”. Each of the &#39;337 application, the &#39;900 application, the &#39;863 application, the &#39;913 application, the &#39;249 application, the &#39;489 patent and the &#39;011 provisional are hereby incorporated by reference in their entireties. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to an apparatus and method for preventing bed bugs from escaping out of a bed mattress. More particularly, the invention relates to a zipper closure structure on a mattress encasement which, while allowing removal of the mattress from the encasement, prevents the escapement of bed bugs out of the mattress and past the encasement. 
     BACKGROUND OF THE INVENTION 
     Bed bugs are a type of insect that commonly hides within bed mattresses. Such bed bugs are found in motels, hostels or boarding houses where itinerant travelers find overnight lodging. Bed bugs will feed off of the blood of humans sleeping on the mattresses that harbor these insects. Typically, a bed bug will crawl out of the mattress during the night, bite the sleeping victim, and then return to the safe confines of the mattress. 
     To prevent the escapement of bed bugs from the mattress, and thus contain and starve the bugs, a technique has been devised in which the mattress is surrounded with a fabric cover or encasement to seal the exit of the bugs. The encasement is slipped onto the mattress and closed via a slide fastening mechanism such as a zipper. Bugs escaping from the mattress will encounter the barrier of the fabric cover, and thus will be prevented from reaching a human sleeping on the mattress. 
     Problems exist, however, with the use of such protective mattress covers or encasements. For example, a user may fail to completely close the zipper on the encasement, or the zipper may become partially unzipped through movement or rustling of the mattress, as for example, when the bed is made and remade. This results in an opening at the zipper end through which bed bugs may escape. Indeed, even zippers that have been carefully and completely closed may still leave a narrow opening at the end of the zipper that is a large enough opening for a small bed bug to crawl through and escape. 
     Accordingly, there exists a need to prevent the escapement of bed bugs from a zipper opening in a mattress protective encasement. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a mattress encasement structure which prevents bed bug escapement from the zipper opening of the encasement. 
     It is yet another object of the present invention to provide a method of preventing bed bugs from exiting a mattress encasement at the zipper end of the encasement. 
     These and other objects of the invention are achieved in a mattress encasement having a zipper opening for receiving a mattress. A barrier structure is disposed at the zipper end of the encasement in order to thwart bed bug travel to any small opening which may form at the zipper end. 
     In addition, objects of the invention are achieved in a method for guiding bed bugs housed within a mattress relative to a zipper portion of a mattress encasement. The bugs are channeled away from the zipper end of the encasement using a barrier structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of a mattress encasement covering a mattress. 
         FIG. 2  is an enlarged top view of a zipper end location of the mattress encasement of  FIG. 1 . 
         FIG. 3  is an enlarged end view of a zipper of the encasement of  FIG. 1 . 
         FIG. 4  is an enlarged cross sectional end view of the zipper end location of  FIG. 2 , taken along line  4 / 4  in  FIG. 2 . 
         FIG. 5  is a cross sectional side view of the zipper end location of  FIG. 2 , taken along line  5 / 5  in  FIG. 2 . 
         FIG. 6  is an enlarged top view of the zipper end location of the mattress encasement of  FIG. 1  in which the zipper is opened providing an opening to the mattress. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIG. 1 , a mattress encasement  100  surrounds a conventional mattress  101 . Mattress encasement  100  may be constructed from a fabric  102  of a size and shape so as to surround and engulf the entirety of mattress  101 . Fabric  102  of the encasement is woven so as to be impervious to bed bugs. 
     An opening  103  is formed at one end  105  of the encasement. Opening  103  extends along the entire width of end  105 , and extends a short distance along each of sides  107 ,  109  of the encasement. Opening  103  allows mattress  101  to slide into and out of encasement  100  so that the encasement may be laundered from time to time. 
     Opening  103  may be closed by a zipper closure  111  to seal the entire encasement opening  103 . Zipper closure  111  includes a zipper head  120  and a pair of zipper tracks  121 ,  123 . Tracks  121 ,  123  are disposed around opening  103  in a confronting relationship and are zipped together in a conventional fashion. Tracks  121 ,  123  have meshable teeth which interleave together as caused by zipper head  120  guiding the two tracks  121 ,  123  together. 
     Referring to  FIG. 2 , zipper head  120  is shown connected to zipper tracks  121 ,  123  and disposed in a position near an end location  125 . End location  125  is where zipper head  120  is stopped from further movement along tracks  121 ,  123 . The tracks are shown intermeshed behind zipper head  120 , as indicated at  134 , to close opening  103  ( FIG. 1 ), and form a seal by the closed tracks that is impervious to bed bugs. Also as indicated at  136 , zipper tracks  121 ,  123  located in front of zipper head  120  are not intermeshed, and define an unzipped portion of the mattress encasement. A small zipper opening  110  is thus formed in front of zipper head  120  in the proximity of end location  125 . Opening  110  extends between end location  125  and zipper head  120 . 
     As shown in  FIG. 2 , a rectangular shaped foam pad  140  is disposed beneath fabric  102 , and thus, beneath the zipper closure at the proximity of end location  125 . As shown in  FIGS. 4 and 5 , foam pad  140  is of a much greater thickness than fabric  102 . 
     Foam pad  140  may be made from a flexible resilient foam material, but other materials may be used as well. For example, foam pad  140  may be a fabric material, a rubber material, or any other material which may be stitched to fabric  102 . In addition, foam pad  140  may be compressible such that contact made by mattress  101  against the lower surface  141  of pad  140  causes the pad to compress between the mattress and the encasement fabric  102 , forcing the top surface  143  of pad  140  into contact with fabric  102  as well as into contact with portions of the zipper structure disposed above pad  140 . 
     As shown in  FIG. 2 , foam pad  140  is stitched to fabric  102  in order to secure the foam pad in place. It is readily apparent from  FIGS. 2 and 4-6 , that the foam pad  140  is a unitary and continuous barrier. A pair of outer rows of stitches  180 ,  182  are formed parallel to and along each side of the zipper tracks  121 ,  123 . Additionally, a pair of inner rows of stitches  160 ,  162  may be formed parallel to and along each side of zipper tracks  121 ,  123 . A fifth row of stitches  164  runs perpendicular to zipper tracks  121 ,  123  and connects all four stitch rows  160 ,  162 ,  180 ,  182 . Row  164  traverses end location  125  of zipper tracks  121 ,  123 . Also, two rows of stitches  181 ,  183  run perpendicular to zipper tracks  121 ,  123  and connect stitch rows  160 ,  180 , and connect rows  162 ,  182 , respectively. Stitch rows  181 ,  183  are co-linear and stop short of the zipper tracks, as shown. 
     Stitching is applied so as to securely attach foam pad  140  to encasement fabric  102 . The stitches are sufficiently close together so as to prevent a bed bug from passing through any of the stitched rows. For example, referring to  FIG. 2 , a bed bug may not pass through stitched row  164 , between pad  140  and fabric  102  to get to opening  110 . 
     Stitching patterns of a rectangular shape are thus formed on each side of the zipper track, attaching foam pad  140  to encasement fabric  102 . As will suggest itself, other stitching patterns may be used. For example a stitching pattern of an “X” shape, or diagonal lines may also be employed. In addition, stitching may encompass end location  125 , as shown at  185 . As shown in  FIGS. 4 and 5 , the fabric  102  may be folded at end location  125  to provide further support, or the like. 
     Referring to  FIG. 3 , zipper closure  111  is shown separate from encasement  100 . Zipper head  120  includes a lower flat planar member  131  which lies below zipper tracks  121 ,  123 . Member  131  serves as one guiding surface to guide the tracks together. The tracks are secured to respective pieces of fabric or extensions  137 ,  139  which provide a means for securing the tracks to the fabric  102 . Fabric extensions  137 ,  139  are shown in  FIG. 2 . 
     Referring now to  FIG. 4 , flat planar member  131  of the zipper head is shown below the two zipper tracks  121 ,  123 . The fabric extensions  137 ,  139  of the tracks are sewn to the casement fabric  102  at respective locations  145 ,  147 , and then fabric  102  is folded back over itself leaving two end portions  149  of fabric  102 . 
     As seen in  FIG. 4 , a space  151  is formed below the zipper tracks  121 ,  123 , and above foam pad  140 . This space  151  provides a channel along which the bottom portion  131  of zipper head  120  moves. As seen in  FIG. 2 , the stitching segments  160 ,  162  form the outer extent of the sides of channel  151 . The top of channel  151  is bound by zipper tracks  121 ,  123  and the bottom of channel  151  is bound by foam pad  140 . Even if a bed bug were to crawl along the entire length of channel  151  toward opening  110 , the bug will be confronted with a barrier posed by lower portion  131  of the zipper head. To thwart the bug from crawling beneath portion  131  of the zipper head, the top surface  143  of the foam pad is forced upwardly into contact with the bottom surface  132  ( FIG. 3 ) of portion  131  by the compression of foam pad  140  caused by the mattress snugly fitting within the encasement fabric  102 . 
     Foam pad  140  is of a length such that when zipper  120  is at a location at or near end point  125 , channel  151  is relatively long making it difficult for a bed bug to crawl through channel  151  to reach the zipper end  125 . 
     In order to prevent bed bugs from escaping through the channel  151 , it is preferred that the maximum height of the channel be small relative to the height of a crawling bed bug and yet provide a sufficient space to receive the lower portion  131  of zipper head  120 . Accordingly, depending on the material of the foam pad  140  and the fabric cover  102 , and the size of the zipper head  120  and zipper tracks  121 ,  123 , the preferred distance between stitching segments  160  and  162 , and the zipper tracks will vary. The size of the channel  151  may also vary depending on the size of the bed bugs intended to be prevented from escaping the mattress. 
     For example, the distance between stitching rows  160 ,  162 , and respective tracks  121 ,  123  may be 1/16 of an inch. The distance between stitching rows  160 ,  162  may be 5/16 of an inch. The distance between stitching rows  164 ,  181  may be 2½ inches. The height of lower portion  131  of the zipper may be 1/32 of an inch. 
     Referring to  FIG. 6 , as zipper head  120  moves along zipper tracks  121 ,  123  and away from foam pad  140 , opening  110  enlarges. As shown in  FIG. 1 , foam pad  140  is located a distance away from end  105  so as to allow opening  110  to enlarge sufficiently to insert and/or remove mattress  101 . As will suggest itself, encasement  100  may be constructed in pieces and sewn together. 
     Accordingly, bed bugs attempting to escape the mattress encasement are impeded from crawling through zipper opening  110  ( FIG. 2 ) without first crawling through channel  151 . When the mattress encasement  100  is properly closed around a mattress, the size of the encasement is such as to fit snugly around the mattress allowing the mattress to abut against foam pad  140 . Foam pad  140  will thus be forced against the tracks  121 ,  123 , and lower portion  131  of the zipper head. The zipper head may be pulled along the tracks and against this bias to open the encasement. 
     While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.