Slide fastener stringer with vent holes

A venting slide fastener stringer for use on a cushion, a pillow, etc. has a warp-knit stringer tape including a pair of laterally spaced, elongate webs with a wale-free region therebetween, and a connecting thread or threads having portions laid in opposed marginal wales in the webs and substantially parallel portions extending transversely across the wale-free region to interconnect the webs, thereby providing a plurality of vent holes longitudinally along the wale-free region. The opposed marginal wales are more rigid than other wales in the webs, and the connecting thread or threads are more rigid than foundation threads making up the webs. A row of coupling elements is mounted on one of the webs remotely from the wale-free region.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a venting slide fastener stringer for 
being attached to cushions, pillows, mats, etc. which require venting. 
2. Prior Art 
There have heretofore been known a variety of venting slide fasteners 
having vent holes in the fastener stringer tapes. One such slide fastener 
disclosed in U. S. Pat. No. 4,125,911, patented Nov. 21, 1978, includes a 
plurality of vent holes punched in stringer tapes of polymer film material 
as shown in FIG. 4 of the accompanying drawings. When the slide fastener 
is transversely stretched in response to a lateral pull, the tapes shrink 
longitudinally and hence get puckered or wavy, which condition causes the 
interdigitating rows of coupling elements are also to become undulated, 
thereby making a slider sluggish during the movement therealong to open or 
close the slide fastener. Garments with such slide fasteners attached are 
also subjected to puckering under the influence of shrinkage of the tapes. 
The slide fastener thus stretched is unsightly and has insufficient 
venting capability due to deformed vent holes. Woven and knitted slide 
fasteners having vents are shown, for example, in Japanese Utility Model 
Publications Nos. 51-135709 and 52-24161 published Nov. 2, 1976 and June 
1, 1977, respectively. 
SUMMARY OF THE INVENTION 
A venting slide fastener stringer has a warp-knit stringer tape including a 
pair of laterally spaced, elongate webs and a wale-free region between the 
webs, the webs being interconnectedby a connecting thread or threads 
running across the wale-free region. The connecting thread or threads have 
portions laid in opposed marginal wales in the webs and substantially 
parallel portions extending transversely across the wale-free region 
between the webs in a direction substantially perpendicular to the 
marginal wales, thereby providing a plurality of vent holes longitudinally 
along the wale-free region. The opposed marginal wales are more rigid than 
other wales in the webs, and the connecting thread or threads are more 
rigid than foundation threads that the webs are knitted of. 
It is an object of the present invention to provide a slide fastener 
stringer with vent holes which is structurally strong against deformation 
in response to a lateral pull. 
Another object of the present invention is to provide a slide fastener 
stringer with vent holes which substantially resists any lateral 
stretching. 
Still another object of the present invention is to provide a venting slide 
fastener stringer of a warp-knit structure having a plurality of vents 
that are resistant to shifting or deformation when subjected to a lateral 
pull. 
Still another object of the present invention is to provide a venting slide 
fastener stringer having sufficient venting capability at all times. 
Many other advantages and features of the present invention will become 
manifest to those versed in the art upon making reference to the detailed 
description and the accompanying sheets of drawings in which preferred 
structural embodiments incorporating the principles of the present 
invention are shown by way of illustrative example.

DETAILED DESCRIPTION 
The principles of the present invention are particularly useful when 
embodied in a venting slide fastener such as shown in FIG. 1, generally 
indicated by the numeral 10. The venting slide fastener 10 comprises a 
pair of slide fastener stringers 11, 12 each including a warp-knit 
stringer tape 13 having a pair of longitudinally extending, parallel 
warp-knit webs 14, 15 for supporting coupling elements and for being 
attached to a garment, respectively, and a longitudinal wale-free region 
16 interposed between the webs 14, 15. The warp-knit webs 14, 15 include a 
pair of confronting marginal wales 17, 18 interconnected transversely by a 
connecting thread 19 having ladder-like parallel portions 20 extending 
transversely across the wale-free region 16 in a direction substantially 
perpendicular to the marginal wales 17, 18, thereby providing a plurality 
of substiantially square vent holes 21 longitudinally along the wale-free 
region 16. 
The slide fastener stringers 11, 12 also include a pair of rows of coupling 
elements 22, 22, respectively, each in the form of a helically coiled 
monofilament, which are mounted on inner confronting beaded edges of the 
stringer tapes 13, 13. The slide fastener can be opened and closed by a 
slider 23 movable along the rows of coupling elements 22, 22 to take them 
into and out of interdigitating engagement with each other. 
As shown in FIG. 2, each of the warp-knit webs 14, 15 is composed of a 
first group of foundation threads 26 knitted as chain stitches in a 
pattern of 1-0/0-1, a second group of foundation threads 27 knitted as 
tricot stitches in a pattern of 1-2/1-0, and a third group of foundation 
threads 28 knitted in a pattern of 0-1/4-3, the foundation threads 26, 27, 
28 thus knitted constituting a plurality of longitudinal wales 29 
juxtaposed across the web 14, 15. The wale-free region 16 is devoid of two 
wales. The connecting thread 19 is laid across the wale-free region 16 in 
a pattern of 0-0/1-1/0-0/4-4/3-3/4-4 so that the connecting thread 19 also 
includes portions 30 laid longitudinally only in the marginal wales 17, 18 
and cooperating with the parallel portions 20 to connect the wales 17, 18 
together. 
The confronting marginal wales 17, 18 comprise in part threads 31, 31', 
respectively, knitted as chain stitches in a pattern of 1-0/0-1. The 
threads 31, 31' are thicker than the foundation threads 26, 27, 28 so that 
the marginal wales 17, 18 are more rigid than the wales 29 in the webs 14, 
15. However, the threads 31, 31' may be made of a plurality of paralleled 
yarns each having the same thickness as that of the threads 26, 27, 28. 
Outermost wales 32, 33 in the webs 14, 15 are also composed in part of 
threads 34, 35, respectively, which are thicker than the threads 26, 27, 
28. However, of the outermost wales 32, 33, only the wale 32 in the 
element-supporting web 14 may be composed in part of the thread 34. 
The connecting thread 19 may be made of twisted yarns (for example, of 500 
denier) which are several times thicker than the threads 26, 27, 28, or of 
paralleled yarns each having the same thickness as that of the threads 26, 
27, 28. 
A warp-knit stringer tape 36 (FIG. 3) constructed according to another 
embodiment is substantially the same as the stringer tape 13 illustrated 
in FIG. 2 except that two connecting threads 37, 38 are laid across a 
wale-free region 41 in symmetrical patterns of 
0-0/1-1/0-0/1-1/0-0/4-4/3-3/4-4/3-3/4-4 and 
4-4/3-3/4-4/3-3/4-4/0-0/1-1/0-0/1-1/0-0, respectively, and one of the webs 
40 which is to be attached to a garment is devoid of some threads 
constituting chain stitches. Each of the connecting threads 37, 38 has 
portions 42 laid in confronting wales 43, 44 and substantially parallel 
portions 45 spaced longitudinally of and extending transversely across the 
wale-free region 41 in a direction substantially perpendicular to the 
wales 43, 44, thereby defining a plurality of longitudinally arranged 
rectangular vent holes 46. With several chain stitches thus omitted, the 
web 40 is relatively flexible to take up stresses applied and hence 
prevent the vent holes 46 from becoming deformed or otherwise adversely 
affected by such stresses. 
With the arrangement according to the present invention, a lateral pull 
applied across the slide fastener 10 is borne at the wale-free region 16, 
41 by the parallel portions 20, 45 of the connecting thread 19, 37, 38 
which run transversely across the wale-free region 16, 41 in a direction 
substantially perpendicular to the wales 17, 18, 43, 44. Accordingly, the 
slide fastener 10 is resistant to being transversely stretched or deformed 
in response to lateral stresses, and hence is free from shrinking 
longitudinally and becoming wavy or puckered in the longitudinal 
direction. Since the vent holes 21, 46 are defined by the lateral thread 
portions 20, 45 of the connecting thread 19, 37, 38 and the rigid wales 
17, 18, 43, 44, they are relatively dimensionally stable and resist 
becoming deformed, thereby providing reliable venting operation when 
subjected to a lateral pull. Furthermore, the connecting thread 19, 37, 38 
is interlaced only with the marginal wales 17, 18, 43, 44 and are 
structurally independent of the webs 14, 15, 39, 40, with the result that 
the vent holes 21, 46 are less adversely affected dimensionally by the 
webs 14, 15, 39, 40. Preferably, each of the holes 21, 46 has 
substantially a size ranging from 0.5 mm.times.0.5 mm to 1 mm.times.1 mm 
and a size ranging from 0.5 mm.times.1 mm.times.2 mm, respectively. 
Although various minor modifications might be suggested by those versed in 
the art, it should be understood that I wish to embody within the scope of 
the patent warranted hereon, all such embodiments as reasonably and 
properly come within the scope of my contribution to the art.