US2887750A

US2887750A - Slide fastener

Info

Publication number: US2887750A
Application number: US514048A
Authority: US
Inventors: Gewis Max; Maeder Werner; Teher Marcell
Original assignee: Worbla A G
Current assignee: Worbla A G; WORBLA AG
Priority date: 1954-10-06
Filing date: 1955-06-08
Publication date: 1959-05-26
Anticipated expiration: 1976-05-26

Description

May 26, 1959 M- GEWIS ETAL ,38

SLIDE FA'STENER Filed June a, 1955 2 She ets-Sheet 1 Fig.2

MAX GEW/S WERNER MAEDER MARCEL TEHER A TTOR/VEYS M. GEWIS ET AL May 26, 1959 SLIDE FASTENER Filed Jur le a. 3 1955 2 Sheets-Sheet 2 INVENTORS MAX GEW/S WERNER MAEDER MARCEL TEHER BY c 1 ATTORNEYS United States Patent O SLIDE FASTENER Max Gewis, Zollikofen-Bern, and Werner Maeder, Flamatt, Switzerland, and Marcell Teher, Sao Paolo, Brazil, assignors to Worbla A.G., Papiermuhle-Bern, Bern, Switzerland, a corporation of Switzerland Application June 8, 1955, Serial No. 514,048 Claims priority, application Luxemburg October 6, 1954 Claims. (Cl. 24-20513) The invention relates to a slide fastener operated by a slide and having interlocking parts. It relates further to a process and apparatus for the manufacture thereof. Slide fasteners of the known designs mostly consist of strips of woven material which are on one edge provided with the interlocking parts such as, for instance,

small individual teeth of metal or of artificial resin or wire spirals. Since from the technical point of view it is diflicult to attach the interlocking parts to the fastening strips and complicated machinery is required for this purpose an attempt has already been made to manufacture the fastening strips and the interlocking parts arranged along one edge thereof all of one piece out of plastics. In realization of this idea two ways were possible; the interlocking parts on either side where formed either uniform or not uniform. In the first case, for instance, teeth have become known whose heads are at one side shaped in the form of hooks whereas the roots of these teeth are divided in such a way as to permit the hooks of the teeth of one strip to engage the openings of the roots of the teeth on the other strip.

Slide fasteners constructed in this manner have, however, proved a failure since the two strips whenrbeing submitted to a certain stress would loosen automatically.

In the second case, for instance, slide fasteners have become known which are provided with round eyes on one side and heads being more or less rounded-off on the other side. On closing the slide fastener or zipper" each head engages two adjacent eyes on the opposite side. It seems obvious that these heads, which,inoreover, consist of a flexible material cannot safely prevent the slide fastener from getting automatically loose.

It has been found that when slide fasteners of the latter kind are submitted to "greater stresses, automatic opening will not take place if on the one side teeth are used whose heads are provided with hooklike lugs which extend in longitudinal direction on both sides and if on the other side one uses eyes of preferably rectangular shape which eyes have a clear width which is only slightly larger than the width of the neck of the teeth. On closing the slide fastener or zipper the two hooklike lugs of each tooth engage two adjacent eyes of the opposite side thus linking the two strips immovably together.

In order to increase its strength each strip may be reinforced along the edge carrying the interlocking parts. For the same reason it is convenient to select a harder plastic material for the interlocking parts than for the fastening strips.

Slide fasteners according to the invention may be produced in an extremely simple and economic way in that suitably rough-molded bands of plastic materials are manufactured by jet molding or extrusion preferably in a continuous working process whereas the eyes respectively teeth are cut out of the edge being provided with a corresponding profile by means of a punching tool and a feed Worm.

If bands are to be manufactured whose interlocking the slide fastener band; at the same time it also punches,

the necessary grooves with the aid of the punching tool. Thus the entire driving machinery is limited to one single shaft, and the risk of producing teeth and grooves of different width arising from the working action of several mechanical parts being moved in relation to each other is effectively eliminated. Furthermore the apparatus according to the invention prevents the bands of plastic materials from warping as is often observed with the conventional punching devices.

In the accompanying drawings a preferred embodiment of the slide fastener and the punching apparatus according to the invention is illustrated by way of example.

Fig. 1 shows a slide fastener in its opened position.

Fig. 2 shows the slide fastener in its closed position.

Fig. 3 illustrates a punching apparatus in top view.

Fig. 4 is a sectional view through the punching apparatus.

According to Figures 1 and 2 the slide fastener comprises two fastening strips 1 and 2. The strip 1 is provided with fiat teeth 3 having heads which are on both sides provided with hooklike lugs 4 and 5 that extend inlongitudinal direction. Furthermore the strip 1 has a reinforced edge 6 on which the teeth are arranged.

The strip 2 having a similarly reinforced edge 7 is provided with eyes-8 which are according to the drawing of rectangular shape. It will, however, be understood, that also eyes of polygonal, oval or any other suitable shape may be used, provided that the clear widthof these eyes does not considerably exceed the width of the neck of the teeth. On closing the slide fastener or zipper each of the teeth 3 engages with its hooklike lugs 4 and 5 the openings of two adjacent eyes-8 thus holding the two strips immovably together even when the slide fastener is submitted to a strong tension or bending stress. The slide fastener or zipper may be opened and closed by using a conventional slide.

The punching apparatus as illustrated in Figures 3 and 4 shows as an essential part a worm wheel 11 mounted on one end of a shaft 12. A driving wheel 13 is arranged on the other end of the shaft 12. This shaft is supported by a bearing 14 which is conveniently built as wide as possible for reasons of taking up vibrations. The worm wheel has mounted to it on the one hand the punching tool 15 and on the other hand a feed worm 16 having a cross section corresponding to the shape of the grooves to be stamped out.

Besides the punching device is provided with a matricedie 17 of known design which is secured to the support 18.

The punching is effected in the manner that at first a groove is stamped into the band to be worked by the punching tool 15 whereupon the band is passed on by the feed worm 16 according to the lead of the latter whereby alb'solutely regular intervals between the grooves are obtained corresponding to the pitch of the worm. In order to prevent the stamped-out particles from clinging to the punching tool the latter is provided with a spring 19 which flings the stamped-out particles away immediately after punching. Furthermore the matrice support 18 is provided with an elastic holding down appliance 20 which on the one hand holds the band and on the other hand serves for equalizing difierences in the 3 thicknessof thematerial to ensure a smooth transport of the band to be punched.

In order to facilitate adjusting of the matrice 17 and the punching tool the matrice support 18 is adjustably mounted onthe base 21. Ifdesired the shaft 12 and the bearing 14 mayalsobe'adjustably arranged.

The slide fastener according to the present invention in connection with the process and apparatusforthe manufacture thereof as described above cannot besurpassed in simplicity andeconomic production by any other known product. As far as flexibility, load capacity and durability are concerned it is, moreover, greatly superior to the known slide fasteners made out of bands of plastic materials.

We claim:

1. A slide fastener comprising two interlocking fastening strips each of which is an integral unit, one of said strips being formed along its'edge with spaced teeth each of which has a-neck portion and a head portion, the latter having two lugs which project in longitudinal direction beyond said neck portion on both sides thereof, each of said lugs being formed with substantially flat faces each of which is spaced'from and substantially parallel to said edge of said one-strip, and the other of said strips being formed along its edge with spaced closed eyes having openings opening in-the direction of the length of such other strip for receiving said lugs of said teeth.

2. A slide fastener as defined in claim 1 wherein each of said fastening strips'is reinforced along its edge.

3. A slide fastener as defined in claim 1 wherein said teeth and eyes are harder than the remainder of the respective fastening strips.

4. A slide fastener as defined in claim 1 wherein said openings are formed-at those portions of said eyes which are furthest from the edge of said other strip with substantially flat surfaces adapted to engage said substantially flat faces of said lugs of said teeth.

5. A slide fastener asdefined in claim 1 wherein said openings in a plane transverse to'the direction of the length of said other strip are of rectangular cross-section.

6. A slide fastener as defined in claim-1 whereinsaid openings, in a plane transverse to the direction of the length of said other strip, are'of rectangular cross-section and wherein that interior surface of each of said openings which is furthest from the edge of said other strip is substantially fiat, whereby said substantially flat faces of said lugsofsaid teeth and said substantially flat surfaces of said openings may engage each other.

7. A- slide fastener as defined in claim 1 wherein each of said strips is formed with a reinforcing rib.

8. A slide.fastener as defined in claim 7 wherein the rib of each strip is formed with a fiat surface constituting the edge of the respective strip.

9. A slide fastener comprising two interlocking fastening strips, one of said strips being formed along its edge with spaced teeth each of which is formed with flat side surfaces and has a neck portion and a head portion, the latter having two lugs which project in longitudinal direction beyond said neck portion on both sides thereof, each of said lugs being formed with substantially fiat faces each of which is spaced from and substantially parallel to said edge of said one strip, and the other of said strips being formed along its edge with spaced eyes having openings opening in the direction of the length of said other strip for receiving said lugs of said teeth, said openings, in a plane transverse to the direction of the length of said other strip, being of rectangular crosssection and that interior surface of each of said openings which is furthest from the edge of said other strip being substantially flat, whereby said substantially flat faces of said lugs of said teeth and said substantially fiat surfaces of said openings may engage each other.

10. A slide fastener comprising two interlocking fastening strips each of which is an integral unit, one of said strips beingformed along its edge with spaced teeth each of which has a neck portion and a head portion, the latter having two lugs which are projected in longitudinal direction beyondsaid neck portion on both sides thereof, each of said lugs being formed with a face spaced from said edge of said one strip with that edge portion of each face which is furthest from the neck portion being spaced atleast as close to said one edge as that edge portion of the face which is nearest to the neck portion, and the other of said strips being formed along its edge with spaced closed eyes having openings opening in the direction of the length of said other strip for receiving said lugs of said teeth.

References Cited in the file of this patent