Patent Publication Number: US-9888747-B2

Title: Zip fastener

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a zip fastener or ‘zip’ which may, for example, be used in circumstances where it is desired to fasten panels of fabric performing a sealing function to each other. In such circumstances, it is naturally desirable for the zip fastening the panels not to compromise the integrity of the seal. 
     2. Description of Related Art 
     One example of such an application is the use of a zip to fasten seat covers; another is the use of a zip to fasten a cover over a mattress where, for example, it is desired to use cover to seal the mattress against infestation by bed bugs. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a zip fastener or ‘zip’ which may, for example, be used in circumstances where it is desired to fasten panels of fabric performing a sealing function to each other. In such circumstances, it is naturally desireable for the zip fastening the panels not to compromise the integrity of the seal. One example of such an application is the use of a zip to fasten seat covers; another is the use of a zip to fasten a cover over a mattress where, for example, it is desired to use cover to seal the mattress against infestation by bed bugs. 
     The present application discloses further embodiments. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Embodiments of the present invention will now be described, by way of example, and with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a zip fastener according to an embodiment of the present invention; 
         FIG. 2  is a perspective view of the zip fastener of  FIG. 1  in a partly unfastened state; 
         FIG. 3  is a plan view of the slider and docking member of the fastener of  FIGS. 1 and 2 ; 
         FIG. 4  is a side view of the slider and docking member of the fastener of  FIG. 3 ; 
         FIGS. 5A and 5B  are plan and side views respectively of a modification of the slider and docking member shown in the embodiment of  FIGS. 1 to 4 ; 
         FIGS. 6A and 6B  are plan and side views respectively of an alternative embodiment of slider and docking member; 
         FIG. 7  is a perspective view of a further embodiment of zip fastener; 
         FIG. 8  is a plan view of the zip fastener of  FIG. 7  in a fastened state; 
         FIG. 9  is a perspective view of a part of an embodiment of docking member; 
         FIG. 10  is a perspective view of a part of a further embodiment of docking member; and 
         FIG. 11  is a plan view of a docking member assembled from two parts according to the embodiment of  FIG. 10 ; and 
         FIG. 12  is a perspective view of a further embodiment of zip fastener according to the present invention in a fastened state. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring now to  FIGS. 1 to 4 , a zip fastener (‘zip’) serves to fasten together two panels of fabric (not shown). The fastener comprises two opposing and mutually engagable rows of teeth  10 ,  12 , each of which is mounted on a stringer tape  20 ,  22 . The fabric panels may be typically be connected to the zip by adhesion to the stringer tapes  20 ,  22 , whether by stitching or glue or some other method. A slider  30  is mounted upon the rows of teeth  10 ,  12  in a manner enabling relative movement of the teeth and the slider  30  (and therefore the slider  30  and the stringer tapes  20 ,  22 ). The slider  30  is movable in a forward direction F to cause interdigitation of the teeth  10 ,  12 , which thereby fastens the zip in a manner well known per se. Backward motion of the slider  30  in the direction indicated by the arrow R causes extradigitation of the teeth  10 ,  12  and thereby unfastens the zip. 
     In the present embodiment, the zip is adapted for use in circumstances where the panels of fabric which it fastens perform a sealing function. Accordingly it is desirable for the zip likewise to act as a seal. To this end, the zip additionally comprises a docking member  50 . The front end  40  of the slider  30  is engagable with the docking member  50  to create a seal between the slider and the docking member  50 . Where engagement of the front face  40  of the slider  30  and the docking member occurs when the zip is fastended along its length, the result is a sealing between the docking member  50  and slider  30  which, along with the sealing action created by the interdigitation of the fastened zip teeth  10 ,  12 , prevents anything on one side of the two panels of fabric from passing to the other side via the zip. 
     In the present embodiment the docking member  50  has the form of a further slider. Accordingly, the docking member  50  is mounted to both stringer tapes  20 ,  22  and is engaged with the teeth  10 ,  12  in a manner which permits it to move along the rows of teeth  10 ,  12 . The configuration of the further slider forming the docking member  50  is such that it is mounted in the opposite direction to the slider  30 . Consequently, motion of the slider  30  and docking member  50  toward each other will cause both to fasten the zip; whilst motion away from each other will cause both to unfasten the zip. This is because motion of the docking member  50  relative to the teeth and tapes  10 ,  12  and  20 ,  22  in the direction F is a backwards motion for the docking member  50  (whereas it&#39;s a forwards and so fastening motion for the slider  30 ) and so unfastens the zip; whereas motion in the direction R, being a forwards motion, fastens it (the same motion for the slider  30  being a backwards, unfastening motion). 
     To provide sealing between the slider  30  and the docking member  50 , a surface on the front  40  of the slider  30  is engagable with a correspondingly-shaped surface on the docking member. In the present embodiment, the front end  40  of the slider  30  has a curved, convex configuration. This cooperates with a correspondingly shaped curved, concave surface  60  on the docking member  50  when the two are in engagement to provide the requisite sealing. In one preferred embodiment, one of the cooperating surfaces  40 ,  60  of the slider  30  and docking member  50  is coated in a resilient coating to aid sealing; in a further preferred embodiment, both surfaces are thus coated. The slider  30  and docking member  50  are shown in their mutually engaged positions in  FIG. 1  and disengaged positions in  FIG. 2 . 
     A locking mechanism is provided which locks the slider  30  to the docking member  50 . The locking mechanism preferably includes cooperable elements on the slider  30  and docking member  50  hold them together in mutual engagement and therefore ensure maintenance of the seal when desired. In the present embodiment, the cooperable elements are provided by a hook  70  on the docking member  50 —here mounted to its upper surface—and a loop  80  pivotally mounted to the slider  30  thereby to form a hasp. Preferably, as in the present embodiment, the loop  80  also serves as the pull tab for the slider  30 . Preferably, as in the present embodiment, the dimension of the loop  80  and spacing of the hook  70  are such that engagement of the loop  80  with the hook  70  retains the slider  30  and docking member  50  in such a manner that force is applied by the front end  40  of the slider  30  to the rear face  60  of the docking member  50  since in this way the seal can be of high integrity. The use of one or more resilient coatings upon the front end  40  and/or rear face  60  assists this since it acts to provide firstly a degree of ‘give’ to accommodate engagement of the hook  70  and loop  80 . Further, once the hook  70  and loop  80  are engaged, the resilient coating(s) provides a resilient reaction force which biases the hook  70  and loop  80  into secure engagement. 
     Referring now to  FIGS. 5A  and B, in a modification of the embodiment shown in  FIGS. 1 to 4 , the hook  70  on the docking member  50  is formed with an aperture  72  which, when the loop  80  is engaged with it, permits a locking rod  90  to be inserted through it thereby to secure the engagement of hook  70  and loop  80 . In the present illustrated example, the locking rod  90  is provided by the clasp of a padlock  100  which thereby enables a secure connection of the slider  30  and docking member  50  against unwanted disengagement. 
     In a further modification shown in  FIGS. 6A  and B locking arms  110 ,  112  on the slider  30  and docking member  50  each have apertures  114 ,  116  which come into register with each other when the surfaces  40  and  60  mate thereby enabling a locking rod  90  to be inserted where desired. 
     Further embodiments of the invention will now be described with, where possible, like reference numerals designating like elements. 
     Referring now to  FIGS. 7 to 10 , a zip fastener comprises two opposing and mutually engagable rows of teeth  10 ,  12 , each of which is mounted on a stringer tape  20 ,  22  to which the fabric panels may be typically be connected to the zip. A slider  130  is connected to the rows of teeth  10 ,  12  and is movable along them (and therefore relative to the stringer tapes  20 ,  22 ) in a forward direction F to cause interdigitation of the teeth  10 ,  12  to fasten the zip. Rearward motion of the slider in the direction indicated by the arrow R unfastens the zip. A further slider  132  is also connected to the teeth  10 ,  12  and operates in the same manner as the slider  30  but with an opposing action. Thus motion of the slider  132  in the direction of arrow R fastens the stringer tapes  20 ,  22  to each other by interdigitation of the teeth; motion in the direction F unfastening the tapes  20 ,  22 . 
     In the present embodiment, the zip is adapted for use in circumstances where the panels of fabric which it fastens perform a sealing function. Accordingly it is desirable for the zip likewise to act as a seal. To this end, the zip additionally comprises a docking member  150  with which the front ends of at least one of the sliders and, more preferably the front end of each of the two sliders  130 ,  132  is engagable (on opposing sides of the docking member  150 ). The docking member  150  is mounted on the zip teeth  10 ,  12  and is likewise adapted for movement along the teeth  10 ,  12  of the stringer tapes  20 ,  22  at a position between the two sliders  130 ,  132 . Thus, the docking member passes over the teeth when the teeth are not in an interdigitated state and the tapes are therefore unfastened in the region of the docking member  150 . It follows that sliding motion of the docking member  150  along the zip has no interdigitating or extradigitating action on the zip teeth  10 ,  12  and that, accordingly, the docking member  150  is not adapted to fasten or unfasten the tapes  20 ,  22 . The function of the docking member  150  is to engage with one or each of the sliders and, thereby, provide mutual connection of the or each of the sliders  130 ,  132 . Preferably this is achieved in a manner which enables the zip to be used as a seal, and therefore the mutual connection provides a suitable sealing between the zip sliders  130 ,  132  and the docking member  150 . 
     Thus, in the present embodiments, the front ends  140  and  142  of the sliders  130 ,  132  each have a curved, convex configuration and the two faces  160 ,  162  of the docking member  150  are correspondingly concave. This configuration provides the mutual engagability of the two sliders  130 ,  132  with the docking member  150  so that such engagement can seal the zip fastener. In a preferred embodiment, to provide optimal sealing between the sliders  130 ,  132  and the docking member  150 , the front ends  140 ,  142  of the sliders  130 ,  132  are curved, convex configuration. This cooperates with a correspondingly shaped curved, concave surfaces  160 ,  162  on the docking member  150  when the two are in engagement to provide the requisite sealing. In one preferred embodiment, one of each of the pairs of the cooperating surfaces  140 ,  160  and  142 ,  62  is coated in a resilient coating to aid sealing; in a further preferred embodiment, both surfaces are thus coated. 
     As with a convention zip fastener, the sliders  130 ,  132  are moved along the zip by means of pull tabs  180 ,  182 , each located on the upper face of its respective slider  130 ,  132  by a bridge member  190 ,  192 . In the present embodiment, the pull tabs each have an asymmetrical configuration such that the distal end of each tab is narrower than its end proximal to the respective bridge. 
     Further, as with the previous embodiment, the present embodiment includes a locking mechanism actuable to lock one or, more preferably both, sliders  130 ,  132  to the docking member  150 . Thus, each of the distal ends includes an aperture  200 ,  202  which is adapted to allow an upwardly extending spigot  210  located on the docking member  150  to pass through the respective aperture  200 ,  202  thereby to form a hasp. The spigots  210  each include an aperture  212  of their own. Accordingly, and referring now additionally to  FIG. 8 , when sliders  130 ,  132  and docking member  150  are in engagement, and the pull tabs  180 ,  182  are pivoted forward onto the docking member  150  so that the spigots  210  each project through the apertures  200 ,  202 , the zip fastener may be locked in the engaged position by the passage of a suitable locking bar (not shown) through each of the apertures, thereby to retain the pull tabs in place on top of the docking member  150  and thereby prevent motion of the sliders  130 ,  132  away from the docking member  150 . 
     In a modification, surfaces on the spigots  210  may be adapted to serve as a cam on the interior surfaces of the pull tab apertures  200 ,  202 , thereby to exert a pulling force acting to urge engagement between the respective slider  130 ,  132  and the docking member  150 . 
     Referring now additionally to  FIG. 9 , the docking member may typically be constructed of two parts, each of which is trapezoidal in shape. In the embodiment of  FIG. 8 , each of the trapezoids is made of a central metal insert  300 , typically of zinc for example, and an outer layer or jacket  302  of more resilient material, typically a suitable form of rubber. The outer layer  302  is smooth at the engagement surfaces  160 ,  162  of the trapezoid but its central surface  304 , to assist the connection of the two trapezoids to form a single, operational docking member  150 . 
     Two trapezoids may be retained or connected to each other by a configuration illustrated in  FIG. 10 . Each trapezoid has a ridge  402  extending longitudinally (with respect to the zip fastener) along its upper and lower surfaces and, extending from one side of the trapezoid, mutually opposing the upper and lower arms  410 , the far ends of which form a pair of inwardly-depending jaws  412 . Referring additionally to  FIG. 11 , the two trapezoids are held in mutual engagement to form a single docking member  150  by the engagement of the jaws  412  of one trapezoid projecting into and thereby engaging with the ridges  402  on the opposing trapezoid, this engagement being enabled by the lateral, mutual offset of the two sets of arms  410 . Engagement of the jaws  412  in the ridges  402  occurs as a consequence of what is, in effect, an intrinsic, inwardly-directed and resilient biasing force which is created once the jaws  412  are urged slightly apart to enable them to come into register with the ridges  402 . That resilient biasing force is typically (though not necessarily) a product of the elasticity of the metal or other material from which the arms  410  are constructed. 
     A further embodiment of zip fastener according to the present invention is illustrated in  FIG. 12 . As previously, the fastener comprises a pair of mutually opposing sliders  130 ,  132  and a docking member  150 . The docking member  150  is constructed in the manner illustrated with reference to  FIGS. 4 and 5 , with the end of an arm  410  just visible. Each slider  130 ,  132  has a pull tab  480 ,  482 , which is fixedly, rather than pivotally attached to it. Each pull tab  480 ,  482  projects forward of the respective slider and beyond the front face  140 ,  142  of that slider. Further, the location at which each of the pull tabs  480 ,  482  is located on its respective slider is laterally offset from the centre line. When the front faces  140 ,  142  of the two sliders come into engagement with the corresponding faces  160 ,  162  of the docking member  150 , the forward ends of the pull tabs  480 ,  482  extend over the docking member  150 . Further, the length of the pull tabs is such that their forward ends then lie adjacent each other and that laterally-extending apertures  512  in each of the forward ends of the pull tabs  480 ,  482  lie in register with each other. This then enables a locking member to be inserted through the two, mutually aligned apertures  512 , to retain the sliders  130 ,  132  in engagement with the docking member  150  by means of engagement of elements on each of the sliders with each other (i.e. in the present embodiment the locking mechanism includes no element on the docking member  150  but relies on the mutual interaction of elements on the two sliders  130 ,  132  to hold the docking member  150  between them). 
     In one preferred embodiment, the locking member may be padlocked, thus enabling some security to ensure that the zip is then retained in its fastened state. 
     The various modifications of the present invention are not limited in their application to the embodiments in connection with which they were first described and, unless stated otherwise, each modification is applicable and has utility in connection with each of the embodiments.