A fluid-tight slide fastener comprising a pair of stringers each having a support tape and a row of coupling elements mounted on and along a folded inner longitudinal tape edge, a slider slidably mounted on the opposed rows of coupling elements, and an end stop mounted on the tapes and having embedded therein a length of the folded edge. Each folded edge includes a sealing abutment extending over a specified length of permenently interengaged coupling element rows adjacent the end stop. The opposed sealing abutments define a substantially inverted "V" cross-sectional profile.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to slide fasteners and more particularly 
to such slide fasteners as are suitable for fluid-tight applications. 
2. Description of the Prior Art 
There have been proposed numerous types of fluid-tight slide fasteners for 
use on for example diving suits, life jackets and other articles requiring 
hermetic seal against leakage. 
A typical known fluid-tight slide fastener comprises a pair of stringers 
each having a support tape resistant to leakage and a row of coupling 
elements mounted on one longitudinal edge of the tape, the stringers being 
coupled and uncoupled by a slider. To establish fluid-tightness of the 
slider, the longitudinal edge of the support tape is folded around the row 
of elements and the thus folded tape edge is externally enveloped by a row 
of sealing clamps positioned in registry with corresponding individual 
elements. Each of the confronting edges of the respective tapes includes a 
vertical rise portion extending between the folded portion and the flat 
tape web, the rise portion being relatively long (as shown in FIGS. 5 and 
6 of the accompanying drawings illustrating a prior art example) so as to 
allow smooth, unrestricted movement of the slider. This prior art fastener 
however is vulnerable because the rise portions of the tapes being 
relatively long tend to crush apart or split under the influence of 
vertically exerted pressures as indicated by dotted lines in FIG. 5, where 
the flat tape webs at their respective ends are bonded to backing strips. 
There is another prior art example of fluid-tight slide fastener in which 
the rise tape portions referred to above are relatively short so as to 
eliminate the possibility of the tape crushing apart or splitting, but 
this example makes it unsmooth, if not difficult, for the slider to move 
along in normal operation of the slide fastener. 
SUMMARY OF THE INVENTION 
With the foregoing difficulties in view, the present invention provides an 
improved slide fastener for fluidtight application which incorporates 
structural features such that the fastener tapes are held immune to 
splitting or crushing apart under severe pressures and allow smooth 
movement of the slider. 
This and other objects and advantages of the invention will appear clear 
from the following description taken in connection with the accompanying 
drawings, in which like reference numerals refer to like or corresponding 
parts throughout the several views.

DETAILED DESCRIPTION 
Referring now to FIG. 1, there is shown a fluid-tight slide fastener 10 
embodying the present invention, the fastener 10 comprising a pair of 
stringers 11 each including a support tape 12 coated with rubber or other 
impermeable material and carrying on and along its inner longitudinal edge 
13 a row of coupling elements 14 which is presently illustrated to be of a 
discrete formation in contrast to a continuous formation. Each individual 
element 14 has a coupling head portion 14a engageable with the 
corresponding coupling head portion 14a on the mating or opposite tape 12 
and a heel portion 14b disposed remote from the coupling head portion 14a. 
The tape edge 13 is folded as at 15 around the heel portion 14b of and 
envelops the major portion of the coupling element 14 as better shown in 
FIGS. 3 and 4. On opposite ends of the folded portion 15 are upper and 
lower sealing abutments 16 and 17, respectively, which are brought 
together by a slider 19 to provide complete seal against leakage in a 
manner well known in the art. Designated at 28 are sealing clamps 
positioned in registry with corresponding elements 14 and stapled around 
the folded edge portion 15 of the tape 12 in a manner well known in the 
art. The tape edges 13 are raised with the coupling elements 14 above the 
flat web surface of the tapes 12 to provide a clearance 18 wide enough to 
permit the slider 19 to move smoothly therethrough. 
The slider 19 is conventional in that it has a slider body 20 and a pull 
tab 21 with which to manipulate the slider 19. 
The slider body 20 includes an upper plate 20a, a pair of side walls 20b 
extending along opposite longitudinal edges of the upper plate 20a, and a 
partition wall 20c disposed centrally between the side walls 20b and 
depending from the upper plate 20a, there being defined in the slider body 
20 a generally Y-shaped guide channel not shown for the passage 
therethrough of the opposed rows of coupling elements 14 to come into or 
out of engagement with each other. The side walls 20b have respective 
flanges 20e, 20e inwardly directed toward each other and receivable in the 
clearance 18. The movement of the slider 19 is limited or stopped at the 
bottom end 22 of the stringer 11 by a bottom end stop 23 which may be 
applied for example by injection molding. 
There is provided a backing sheet 24 which is partly connected and adhered 
to the lower surface of the bottom end portion 22 of the support tape 12 
to reinforce the latter. The portion of the backing sheet 24 which is thus 
joined to the support tape 12 extends long enough to lie under the slider 
19 when the latter is brought fully back in abutting engagement with the 
bottom end stop 23 as better shown in FIG. 2. 
The bottom end stop 23 is substantially in the form of a rectangular block 
which is made preferably of a thermoplastic resin for its feasibility of 
being molded into a desired shape and for its flexibility of yielding to 
pressures exerted by the slider 19. The end stop 23 has a bottom 
peripheral portion flattened out of provide a thin flared seat or fin 25 
which is effectively anchored adhesively or fusibly partly to the bottom 
end 22 of the tape 12 and partly to the reinforcing backing 24 across a 
marginal end extremity 26 of the tape 12 as shown in FIGS. 1 and 2. The 
end extremity 26 is rounded off to facilitate the attachment of the end 
stop 23 and to minimize friction with ambient objects. The end stop 23 has 
a front vertical end wall 27 with which the slider 19 is brought in 
abutting engagement as shown in FIG. 2. The end stop 23 contains or has 
embedded therein a portion of interengaged folded edges 13 of the tape 12 
including a plurality of coupling elements 14 and is thus attached 
adhesively, ultrasonically or by injection-molding to provide firm 
anchoring of the end stop 23 with respect to the support tape 12 against 
severe thrusting force of the slider 19. 
A top end stop though not shown is substantially the same in construction 
as the bottom end stop 23 above described. 
Now, according to an important feature of the invention, the slide fastener 
10 has a length 13a of folded tape edge 13 which extends from within the 
end stop 23 over a plurality of coupling elements 14 permanently 
interengaged adjacent to the end stop 23, said length 13a defining an end 
region of stringers 11 in which confronting lower sealing abutments 17' of 
the respective tapes 12 are separated divergently at an angle to assume a 
substantially inverted "V" cross-sectional configuration as shown better 
in FIGS. 3 and 4. The portion 24' of the backing sheet 24 which is 
coextensive with the specified length 13a of stringers 11 is centrally 
flexed in conformity with and attached to the inverted "V" portion of the 
sealing abutments 17'. This structural feature serves to dissipate 
vertically exerted pressures which would otherwise work upon and cause the 
sealing abutments 17 to crush apart as in the case of a prior art 
counterpart shown in FIG. 5. 
Another advantage of the invention is that the provision of the above 
configured sealing abutments 17' gives the clearance 18 a sufficient width 
to permit smooth movement of the slider 19 as compared to a prior art 
counterpart shown in FIG. 7. 
Although various minor modifications may be suggested by those versed in 
the art, it should be understood that I wish to embody within the scope of 
the patent granted hereon, all such embodiments as reasonably and properly 
come within the scope of my contribution to the art.