US3629911A

US3629911A - Slide fastener

Info

Publication number: US3629911A
Application number: US806620A
Authority: US
Inventors: Bernd Porepp
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-03-13
Filing date: 1969-03-12
Publication date: 1971-12-28
Anticipated expiration: 1988-12-28
Also published as: BR6907076D0; GB1267677A; AT307342B; DE1660799A1; NL157495B; NO124190B; DE1660799B2; CH487610A; ES364505A1; NL6903664A; SE358285B; FR2003841A1; BE729734A

Abstract

A slide fastener comprises a pair of rows of continuous links of plastic material formed with coupling heads at adjacent inner edges of the rows. The coupling heads engage in coupling spaces formed by depressions in legs of the links. Projections formed on the legs prevent shifting of mounting threads toward the coupling spaces.

Description

United States Patent [7 2] Inve ntor Bernd Porepp 16 Am Rebberg, 7764 Wangen (Bodensee), Germany [21] Appl. No. 806,620

[22] Filed Mar. 12, 1969 [45] Patented Dec. 28, 1971 [32] Priority Mar. 13, 1968 [3 3] Germany [54] SLIDE FASTENER 3 Claims, 6 Drawing Figs.

[52] U.S.C1 24/205.1, 24/205.13, 24/205.16 [51] 1nt.C1 ..A44b 19/12, A44b 19/34 [50] Field 01 Search 24/205.13 C, 205.16 C, 205.1 C, 205.13 C

[56] References Cited UNITED STATES PATENTS 3,149,388 9/1964 Wilcken ..24/205.13 C UX 3,128,518 4/1964 Steingrubner.. .....24/205.l3CUX 3,490,110 1/1970 Frohlich ..24/205.l3CUX Primary Examiner- Bernard A. Gelak Attorney-Polachek, Saulsbury & Hough ABSTRACT: A slide fastener comprises a pair of rows of continuous links of plastic material formed with coupling heads at adjacent inner edges of the rows. The coupling heads engage in coupling spaces formed by depressions in legs of the links. Projections formed on the legs prevent shifting of mounting threads toward the coupling spaces.

PATENTEU M82819?! 55mm POIFEPP By Ema/roe @u/W rm 5 sum: FASTENER BACKGROUND OF THE INVENTION In known slide fasteners comprising rows of continuous links made of a string of plastic material shaped to a flattened helical spring, individual convolutions or links of the pair of link rows are provided with coupling heads at their apexes facing each other at adjacent edges of the rows. The heads merge into superposed link legs connected by loop portions of the convolutions. The coupling heads of the pair of link rows generally mutually engage alternately, directly one behind the other when the link rows are brought into coupling engagement by a slide. In this the points of the coupling surfaces engaging one behind the other form a continuous line about which the two link rows may tilt perpendicularly to the coupling plane, so that the coupling heads can easily be disengaged.

As is well known in the art each slide fastener half comprises a carrier ribbon to which the link row is secured usually by sewing a seam of chain stitches. Often the slide fastener is rendered unserviceable because the threads of the seam become displaced toward the coupling heads so that movement of the slide is prevented.

It is therefore, an object of the invention to prevent the possibility of twisting the link rows about a longitudinal axis, and to reduce the possibility of accidental separation of the coupling heads of the slide fastener.

Another object of the invention is to provide a slide fastener including means for preventing the link rows from twisting relative to the plane of the slide fastener about a longitudinal axis and also to provide means for preventing the displacement toward the coupling heads of the seam threads, by means of which the link rows are secured to their respective carrier ribbons.

SUMMARY OF THE INVENTION According to the invention, at least one of the superposed legs of each link in each row of links is provided with a recess or depression at its inner side. Each depression is spaced from the coupling head of each link. The depressions define spaces between the legs of each link in each row thereof to receive the coupling heads of the links in the other link row.

The invention is an improvement over the prior art since the coupling points between the slide fastener halves do not follow a straight line, as was customary practice, but are spaced from each other, i.e., alternately staggered in longitudinal direction along a zigzag line. Thus angular movements of the slide fastener halves about their coupling points are prevented, and the danger of unintentionally breaking the coupling engagement is greatly reduced.

The secure grip of the interlocking engagement between the two slide fastener halves is further improved, in that both legs of each links of both link rows are provided with depressions disposed oppositely to each other at the inner sides facing each other. These depressions define enlarged coupling spaces in each link row for receiving the coupling heads of the other link row.

The invention involves a further improvement in that an outward projection and another depression are fonned in the legs of the links and spaced from the coupling headQThe projection prevents shifting of seam threads from the other depression. This prevents interference with movement of the fastener slide.

The invention will now be described in detail in connection with the attached drawing showing several exemplified embodiments of the invention. It is to be understood, however, that the invention shall not be restricted to these embodiments, as changes or alterations are conceivable without departing from the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial top view of a pair of link rows of a slide fastener in the form of flattened helical springs made of a string of plastic material;

FIG. 2 is a cross sectional view along the offset line IllI in FIG. 1 on a larger scale;

FIG. 3 is a further enlarged top view of a pair of coupled links of the pair of link rows of the slide fastener;

FIG. 4 is a schematic sectional view of a tool for producing the coupling surfaces and the depression in the legs of the links;

FIG. 5 is a partial top view of a profiled string with a coined coupling surface and a depression in the leg of the links; and

FIG. 6 is a cross-sectional view of a row of links of a slide fastener employed in the string shown in FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, two rows of slide fastener links 1 and 2 helically wound in counter directions and provided with

coupling heads

3 and 4 are shown. The legs, or

convolution portions

5, 6 and 7, 8 extending away from the

coupling heads

3, 4 are disposed in spaced superposed relation to each other, or nearly contacting each other respectively, and then merge into the connecting arcs or

loops

9 and 10.

According to the invention the

legs

5, 6 and 7, 8 of the pair of link rows are provided with recesses or

depressions

11, 12 and l3, l4 oppositely disposed at the inner sides which face each other and are equally spaced from the

coupling heads

3 and 4, An eye or coupling space is formed within which the free ends of the

coupling heads

3, 4 are received in a coupling relationship when the link rows 1 and 2 of the slide fastener, which are each sewed to carrier ribbons l5 and 16, are brought into meshing engagement by means of a slide (not shown). The points of interlocking engagement of the

coupling surfaces

3 and 4 of the pair of link rows with the coupling spaces defined by depressions ll, 12 and 13, 14 are spaced apart transversely relatively to the longitudinal direction of the coupled slide fastener halves. The slide fastener links of the link rows cannot move in a vertical direction with respect to the slide fastener plane. Also they cannot twist angularly to each other and relative to the plane of coupling. Thus the possibility of unintended breakage of the coupling is reduced. However, the slide fastener can be flexed in any direction.

In many cases it will suffice, as shown in FIG. 6, to merely provide one recess or

depression

12 or 14 in each one of

legs

6 and 8 respectively, of the pair of link rows of the slide fastener.

Recesses

11 and 13 will be omitted. Recesses l2 and 14 will be located at inner sides of

legs

6 and 8 in order to provide coupling spaces for the

coupling heads

3, 4 of the other link row. Thus twisting and accidental separation of the coupled links will be prevented.

In shaping the string of plastic material to a flattened helical coil, one may proceed, according to FIGS. 4 and 5 in such a manner that the coupling,

heads

3 or 4 respectively, are formed by a pressing action of a top die 17 provided with a coining projection I9 and a bottom die 18. The top die 17 is also provided with a second coining projection 20 of lesser height spaced relative to the first coining projection 19. This second coining projection 20 serves to provide the recesses or

depressions

12 or 14 respectively, in the legs of the links. It is also possible to provide a recess 21 in the bottom die 18 opposite to the second coining projection 20 and to provide behind the recess 21 a third coining projection 22 projecting slightly upwardly beyond the plane of the bottom die 18. Thereby the material of the string, displaced during the pressing action by the second coining projection 20, is urged into the recess 21 and thickened by the third coining projection 22. Thereby a small projection 23 of the string is formed andadjacent thereto a recess 24 is formed opposite from the depression 12. Recess 24 serves to receive the lower thread loops of a chain stitch seam 25, for example'The projection 23 prevents shifting of the seam in a direction toward the depression and the coupling head which engages therein.

I claim:

1. A slide fastener mountable on a carrier ribbon, comprising a pair of strings of plastic material formed into a pair of longitudinally parallel rows of links, inner edges of the rows being disposed adjacent to each other, each link having a pair of overlapping legs extending in a plane transversely of the row and terminating at a coupling head at the inner edge of the row, said heads being widened to define oppositely directed apical portions in the longitudinal direction of the rows, said legs engaging each other from substantially the head along a portion of said legs, one of the legs of each link in each row being formed with a depression on the inner edge of said one leg facing its opposite leg and spaced from the head of the link by said engaging portion to define a coupling space with the other leg of the link to receive the coupling head of another link in the other row.

2. A slide fastener as defined in claim I wherein the other leg of each link is formed with another depression facing the depression in said one link for enlarging said coupling space to receive the coupling head of said other link in said other row.

3. A slide fastener as defined in claim I, wherein another depression is formed in said one leg adjacent to the first named depression and further spaced from said head for engaging a thread of a seam in said ribbon, and a projection formed on said one leg between the two depressions to prevent displacement of said thread from said other depression.

II l =0

Claims

1. A slide fastener mountable on a carrier ribbon, comprising a pair of strings of plastic material formed into a pair of longitudinally parallel rows of links, inner edges of the rows being disposed adjacent to each other, each link in each now having a pair of overlapping legs extending in a plane transversely of the row and terminating at a coupling head at the inner edge of the row, said heads being widened to define oppositely directed apical portions in the longitudinal direction of the rows, said legs engaging each other from substantially the head along a portion of said legs, one of the legs of each link in each row being formed with a depression on the inner edge of said one leg facing its opposite leg and spaced from the head of the link by said engaging portion to define a coupling space with the other leg of the link to receive the coupling head of another link in the other row.

2. A slide fastener as defined in claim 1 wherein the other leg of each link is formed with another depression facing the depression in said one link for enlarging said coupling space to receive the coupling head of said other link in said other row.

3. A slide fastener as defined in claim 1, wherein another depression is formed in said one leg adjacent to the first named depression and further spaced from said head for engaging a thread of a seam in said ribbon, and a projection formed on said one leg between the two depressions to prevent displacement of said thread from said other depression.