Abstract:
A vacuum press fit zipper assembly designed for watersports apparel and gear and other water related applications. Overmolding construction forms an effective seal around the entire perimeter of the fastener assembly, and a vacuum fit is created between the two mating portions of the zipper assembly.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/416,068 filed Mar. 31, 2009, which claims benefit of the filing date of 31 Mar. 2008, for the U.S. Provisional Patent Application to Brightman, having the Ser. No. 61/072,628. 
    
    
     BACKGROUND OF THE INVENTION 
     Standard zipper fasteners, like those typically found on garments and sportsgear, are great for their limited use as linear fasteners. However, they do not work well to prevent water from soaking through, even if the fabric of the garment itself is water resistant. There are extruded linear fasteners, such as is used with the trademarked Ziploc® food bags. Yet, the Ziploc® fastener, even with a slider, would not work well with garments and sports bags, mainly because the user would be unable to brace the fastener from within. 
     SUMMARY 
     The invention, in its simplest form, is a waterproof submersible vacuum-fit zipper or vacuum press fit zipper assembly. The zipper or zipper assembly is comprised of two mating parts forming the fastener assembly (see  FIG. 3A ) that, when engaged, create a partial vacuum (vacuum). When the partial vacuum is created, a watertight, airtight seal is formed. The two mating parts fit together with such precision, and with such robust design, that the assembly also prevents capillary action. 
     The mating parts are made of flexible elastomer-like material that can be produced through an extrusion, or injection molding process. 
     The unique design allows a watertight, airtight zipper to be easily engaged (closed) and then disengaged (opened) by way of pull tabs. The user simply slides the thumb and forefinger or slider the length of the zipper to close, and then pulls on the outside of the zipper via pull tabs to open. 
     This ease of use, flexible, watertight, airtight zipper design is useful in many water related applications, such as water sports apparel and gear. 
    
    
     
       DESCRIPTION OF DRAWING VIEWS 
         FIG. 1  is a perspective view of the invention in one of many possible embodiments. 
         FIG. 2  is a close-up perspective view of the invention. 
         FIG. 3A  is a very close-up end view of the extrusions that fasten together and are comprised by the invention. 
         FIG. 3B  is a very close-up end view of the female portion of the fastener. 
         FIG. 3C  is a very close-up end view of the male portion of the fastener. 
         FIG. 4  is a very close-up perspective view of the over-molded end cap, which seals each end of the fastener. 
         FIG. 5  is a very close-up perspective view of the slider, which is comprised by an alternate embodiment of the invention. 
         FIG. 6  is a close-up perspective view of an alternate embodiment of the invention, which comprises a slider to aid in fastening. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows one embodiment of the invention, as it is integrated with a durable sports bag  10 . The zipper assembly  20  has been radio frequency welded into place within the opening of the bag  10 , to form a watertight product. The zipper assembly  20  is engineered and constructed in a way that it forms an effective seal around its entire perimeter, and between the two mating portions  30  and  31  as shown in  FIG. 2 . 
       FIG. 2  shows the invention in its preferred embodiment. The zipper assembly comprises a female extrusion  30 , a male extrusion  31 , and an over-molded end cap  40  at each end of the fastener assembly  25 . (See  FIG. 3  for a more detailed view of the extrusions  30  and  31 , and  FIG. 4  for a view from below the over-molded end cap  40 .) 
     Referring to  FIG. 3A , the female extrusion  30  is shown joined with the male extrusion  31  such that the female member  32  and male member  33  engage each other, creating a partial vacuum (vacuum) there between. This precision fit permits a watertight, airtight seal that prevents capillary action from occurring. 
     More specifically, as shown in  FIGS. 3A and 3B , female member  32  is of an upstanding C-like configuration having a slide extension or protrusion  34  formed on one side thereof, an interior cavity  35  formed in the interior opposite extension  34 , and a pair of curved segments  29 . This configuration is of a precise shape which forms the C-like configuration. An elongated entrance opening  36  terminates in an interior, bulb-like configured opening  37 . The socket configured opening  37  includes two flat interior surfaces  38  used to lock the male member  33  in place to assist in the creation of the vacuum within cavity  35  in a manner set forth below. 
     Reference is once again made to  FIGS. 3A and 3C , where male member  33  of male extrusion  31  is depicted as an upstanding mating element. More specifically, male member  33  has a slide extension or protrusion  39  on an exterior surface of member  33  and a protruding member or protrusion  41 . Protruding member  41  includes a stem  42  terminating in bulb or bulbous section  43 . The bulbous section  43  has a pair of flat exterior surfaces  44  which are used to engage interior flat surfaces  38 , respectively to lock the bulbous section  43  within socket opening  37  creating a vacuum within cavity  35 . Cup-like exterior segments  45  terminate in tips  46  so as to enable their tight fit to curved segments  29 , respectively. 
     The female member  32  and male member  33  are made of a soft elastomeric-like material and must be precisely configured to approximately mate with one another. As the female member  32  and male member  33  engage each other to form the watertight, airtight seal, a vacuum or partial vacuum is found within cavity  35  as air leaves the cavity  35 . Although it is possible to slide the female member  32  and male member  33  together to close the fastener assembly  25 , fastening of fastener assembly  25  can also be accomplished when a slide  50  is used, which encompasses female member  32  and male member  33 . Slide  50  is slid in one direction to close the fastener assembly  25  and then in the other direction after separating the female member  32  from the male member  33 . Separation occurs when pull tabs  60  are used to pull apart the female and male members. 
     The material that forms the extrusions  30  and  31  and over-molded end cap  40  is a soft elastomer-like material, between 80 and 90 Shore A in hardness. Suitable materials include thermoplastic polyurethane (TPU) and polyvinyl chloride (PVC). 
     Note the dotted lines in  FIG. 2 , which indicate the locations where the end caps  40  are fused to the extrusions  30  and  31 , during the over-molding process. The locations are shown as dotted lines because the zipper assembly  20  is practically seamless, and the surfaces of the end caps  40  match those of the extrusions  30  and  31 , to form a single surface around the entire perimeter of the zipper assembly  20  above, and a single surface around the entire perimeter of the zipper assembly  20  below. This provides for a hermetic seal, and an attachment area that runs 360 degrees around the zipper assembly  20  for installment. 
     This is a unique use of the over-molding process for assembly, which allows parts to be butted together to form a flat and continuous surface between parts. This saves on material costs, and on mold tooling complexity. In this case, the flat surfaces formed into the invention allow the zipper assembly  20  to be bonded (in this case, RF welded) to the fabric of a garment or bag  10 , so that a hermetic seal is possible between them. Overlapping portions, or material discontinuities, would otherwise make the step of complete sealing very difficult, if not impossible. In this usage, the over-molded end cap  40  uses the same material as the extrusions  30  and  31 , which is of the same durometer/hardness, 80-90 Shore A. 
       FIG. 3A  shows one end of both mating parts, as a fastened fastener assembly  25 . The male and female extrusions  30  and  31  are extruded, in this case. 
     The fastener assembly  25  is secured with a mechanical “ball-and-socket” union (a combination of a press fit and an interference fit) as well as with a vacuum. The female member  32  of female extrusion  30  accepts the male member  33  of male extrusion  31  to form a precision fit and a vacuum seal. The corresponding features shaped into each mating part  32  and  33  actually force all of the air out of the cavity  35  of fastener assembly  25 , and creates what is called the vacuum fit. This special fit resists separation and bolsters the strength of the mechanical union between the two mating parts or extrusions  30  and  31  by mating surfaces  38  and  44 . 
     Also, because all of the air is removed from between the two parts, female member  32  and male member  33 , upon fastening, any capillary action that would otherwise fill voids or the cavity  35  with water (or other fluid) is prevented. Another hermetic seal is produced between the two extrusions  30  and  31 . 
       FIG. 3B  shows one of the female extrusions  30  by itself. 
       FIG. 3C  shows one of the male extrusions  31  by itself. 
       FIG. 4  shows a view from below an end cap  40 . The end cap  40  is over-molded, onto the end of the zipper assembly  20 , to form yet another hermetic seal. In this view, a cavity is visible, where the assembly of two mating extrusions  30  and  31  fit together and are located upon molding. (The thickness of the flange on the end cap  40  is the same as the thickness of the flange of each of the extrusion  30  and  31 .) 
       FIG. 5  shows a close-up view of the slider  50 . This part is in the shape of a housing  51  having an internal tunnel-like configuration with a pair of oppositely disposed grooves or slots  52  which slideably mate with the opposed extensions or protrusions  34  and  39 , respectively. Slider  50  may be snapped into place over the male and female members  32  and  33  of fastener assembly  25  at any time, once the extrusions  30  and  31  have been mated. Although the fastener assembly  25  may be closed by using two fingers alone, the slider  50  can be used instead. The fastener assembly  25  then may be opened by pulling the openers  60  (as shown in  FIG. 1 ) in substantially opposite directions. 
     The slider  50  is injection-molded of a hard plastic with a low coefficient of friction, in this case, acetal with 20% polytetrafluoroethylene (PTFE) (Teflon®). 
       FIG. 6  shows an alternate embodiment of the zipper assembly  20 , which includes the slider  50 . This view also shows the end cap  40  on either end of the zipper assembly  20 .