US3812754A

US3812754A - Apparatus for producing fastener-element-free gaps in a continuous slider fastener chain

Info

Publication number: US3812754A
Application number: US00367711A
Authority: US
Inventors: K Kawakami
Original assignee: Yoshida Kogyo KK
Current assignee: YKK Corp
Priority date: 1972-06-10
Filing date: 1973-06-07
Publication date: 1974-05-28
Anticipated expiration: 1991-05-28
Also published as: DE2329437A1; FR2187251B1; GB1378126A; CA976474A; SE399637B; DK130864B; NL7307949A; DK130864C; BR7304307D0; JPS4916539A; DE2329437B2; FR2187251A1; BE800724A; AU5663073A; IT984671B; HK33277A; ES415707A1

Abstract

An apparatus is disclosed for producing fastener-element-free gaps in a continuous slide fastener chain. The apparatus comprises a punch block, a cutting punch reciprocally movable therein, and a die block positioned in oppositely spaced relation to said punch block and having a recess for receiving a group of fastener elements to be severed, said cutting punch having an upward stroke limited such that the distance between an extreme operating end of said punch and the bottom surface of said recess is smaller than the overall thickness of said fastener chain but larger than the thickness of said fastener elements. The arrangement of the apparatus ensures that adjacent longitudinal edges of the fastener stringer tapes are deflected upwardly progressively away from each other as the fastener chain is moved past the cutting punch so that a group of fastener elements severed off the deflected edges of said tapes along a length of the chain corresponding to a fastener-element-free gap to be produced.

Description

United States atent n91 Kawakami 1 APPARATUS FOR PRODUCING FASTENER-ELEMENT-FREE GAPS IN A CONTINUOUS SLIDER FASTENER CHAHN [75] Inventor: Koichi Kawakami, Toyama, Japan [73] Assignee: Yoshida Kogyo Kabushilki Kaisha,

Tokyo, Japan [22] Filed: June 7, 1973 [21] Appl. No.2 367,711

[30] Foreign Application Priority Data June 10, 1972 Japan 47-57938 I [56] References Cited UNITED STATES PATENTS 4/1964 Fasciano 83/921 X 12/1965 Fasciano 83/921 X [451 May 28, 1974 Primary ExaminerFrank T. Yost [57] ABSTRACT An apparatus is disclosed for producing fastenerelement-free gaps in a continuous slide fastener chain. The apparatus comprises a punch block, a cutting punch reciprocally movable therein, and a die block positioned in oppositely spaced relation to said punch block and having a recess for receiving a group of fastener elements to be severed, said cutting punch having an upward stroke limited such that the distance between an extreme operating end of said punch and the bottom surface of said recess is smaller than the overall thickness of said fastener chain but larger than the thickness of said fastener elements.

The arrangement of the apparatus ensures that adjacent longitudinal edges of the fastener stringer tapes are deflected upwardly progressively away from each other as the fastener chain is moved past the cutting punch so that a group of fastener elements severed off the deflected edges of said tapes along a length of the chain corresponding to a fastener-element-free gap to be produced.

2 Claims, 11 Drawing Figures i2 M m 9 PATENTEB NY 28 m4 SHEET 1 BF 3 FIG.4

FI,G.5

BACKGROUND OF THE INVENTION This invention relates to apparatus for forming fastener-element-free gaps or spaces at predetermined intervals in a continuous length slide fastener chain, more particularly a chain consisting of a pair of oppositely disposed stringer tapes carrying along their adjacent longitudinal edges two rows of interlocking fastener elements, the coupling parts of which elements on the one stringer tape extend into the longitudinal. edge region of the other or mating stringer tape when the fastener is closed.

There have been proposed many different apparatus for the production of the aforesaid fastener-elementfree gaps in a continuous fastener chain which are utilized for mounting sliders and end stop members on individual lengths of slide fasteners made from the chain. Most of such known apparatus have involved means of spreading the two opposed stringer tapes apart by a distance large enough to permit of the entry of a cutting punch therebetween to sever a group of fastener elements from the respective tapes. A typical example of such prior-art device is designed to pull the opposed stringer tapes transversely apart at the desired location of a fastener-element-free gap to expose the interengaged parts of the elements and thereafter cut the elements between the pulled-apart adjacent edges of the tapes. However, this device is liable to the drawback that the opposed tapes are not always spread apart widely enough for the punch to move therebetween depending upon the tension with which they are pulled apart, with the results that the adjacent tape edges are often marred or damaged by the punch when operated to remove the elements. Furthermore, the conventional apparatus is rather complicated with added means of pulling the tapes apart and is troublesome in the handling, adjustment and servicing of operating parts of the apparatus and hence it is not suitable for use for instance by trouser manufacturers who would often prefer to buy a continuous fastener chain instead of measured individual fasteners and cut the chain to provide slide fasteners of desired product length at their discretion.

SUMMARY OF THE INVENTION With the above noted difiiculties of the prior-art in view, the primary object of the present inveniton is to provide an improved apparatus for the production of fastener-element-free gaps in a continuous length fastener chain of the type described, which apparatus is simple yet reliable in separating two opposed stringer tapes apart and severing a group of fastener elements along a length corresponding to a desired element-free gap to be formed, without damaging the tape edges or the stitches holding the elements thereto.

A more specific object of the invention resides in the provision of an inventive concept wherein there is provided a cutting punch having a bifunctional performance firstly of spreading apart the stringer tapes without resort to any special added separating device and secondly cutting a length of fastener elements to produce a fastener-element-free gap as desired.

These and other objects and advantages of the invention will be better understood from the following detailed description of some preferred embodiments taken in connection with the accompanying drawings wherein like reference characters refer to like or corresponding parts throughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a plan view showing a segment of a continuous fastener chain having two interengaged stringer tapes and indicating a measured length of longitudinal space or gap to be produced therein;

FIG. 2 is a plan view similar to FIG. I but showing a cutting punch interposed between and separating adjacent longitudinal edges of the respective stringer tapes at the said measured length of gap to be produced;

FIG. 3 is a view similar to FIG. 2 but showing a group of fastener elements just removed along the said measured length;

FIGS. 4 through 7 inclusive are diagrammatic views utilized to explain the sequential steps of the process and the essential parts of the apparatus employed to carry the same into practice according to the invention; FIG. 4 showing now the fastener chain is introduced into the apparatus; FIG. 5 showing how the fastener chain is delivered progressively toward and separated by the cutting punch; FIG. 6 showing the adjacent longitudinal edges of two opposed stringer tapes spread apart just prior to the severing of fastener elements; and'FIG. 7 showing how the fastener elements are cut and removed from the stringer tapes;

FIG. 8 is a diagrammatic front elevational view of the apparatus;

FIG. 9 is a cross-sectional view taken on the line AA of FIG. 8;

FIG. 10 is a plan view of a segment of continuous fastener chain having produced therein a modified form of a fastener-element-free gap; and

FIG. 11 is a diagrammatic view of the essential parts of apparatus designed to produce the said modified element-free gap.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings and FIGS. 1 to 3 in particular, there is shown a continuous slide fastener chain used in the practice of the invention, which chain generally designated at F comprises a pair of oppositely disposed stringer tapes T,T having mounted along their adjacent longitudinal edges Ta,Ta two rows of fastener elements E formed from a continuous plastic filament into a spiral or coil structure such that the coupling parts Ea in the row of elements on one stringer tape, when the fastener chain is in closed disposition, extend into the longitudinal edge Ta of the other or mating stringer tape.

The rows of such fastener elements E are secured to the respective stringer tapes T,T on one side thereof as by longitudinal lines of stitches S,S (best shown in FIGS. 4, 6, 7 and 11).

The inventive concept of the present invention may be best understood by reference to FIGS. 4 to 7, which concept essentially comprises deflecting the adjacent longitudinal edges Ta,Ta of two stringer tapes T,T upwardly apart progressively by moving the fastener chain F in engagement with a cutting punch later described and cutting a group of fastener elements E with said cutting punch along a length corresponding to a fastener-element-free gap to be formed in the chain F. One preferred form of apparatus employed according to the invention is illustrated in FIGS. 4 to 9, and referring to FIG. 9 in particular, the gap producing apparatus 10 comprises a support frame 1 1, a punch block 12 and a die block 13, both blocks being housed in said frame 11. There is provided a cutting punch 14 mounted in the punch block 12 and vertically movable relative thereto by means of a suitable known actuating mechanism not shown. The die block 13, which is disposed in opposite relationship to the punch block 12, is provided in its upper surface with a recess 15 for receiving a group of fastener elements E. Centrally of the recess 15 is formed a punch receiving opening 16 positioned in registry with the path of the cutting punch 14 and dimensioned to fit the width thereof. The punch receiving opening 16 is defined by coacting

cutting edges

17,17 which coact with the cutting punch 14, more specifically with bladed edges 14a thereof, in severin g the elements E off the fastener chain F as best depicted in FIG. 7.

According to the principles of the invention, the fastener elements receiving recess 15 is dimensioned such that a distance H between the bottom surface 15a of the recess 15 on which the elements E are seated and the operating end 14b of the cutting punch 14 in the limit of its upward stroke is smaller than the overall thickness A of the fastener chain F but larger than the thickness B of the fastener elements E per se, as best depicted in FIG. 4. This arrangement ensures that the cutting punch 14 can separate the adjacent longitudinal edges Ta,Ta of the opposed sctringer tapes T,T and cause the same to become deflected upwardly apart as the fastener chain F is fed progressively through the punch 14.

The position of the cutting punch 14 in which it func tions to separate or spread apart the adjacent edges Ta,Ta of the tape T,T; namely, the requisite distance H, can be secured by limiting or terminating the upward stroke of the punch 14 thereat for example with use of a suitable stopper means not shown in connection with the punch actuating mechanism as may readily occur to one skilled in the art.

The precise positioning of the cutting punch 14 as above described further ensures that the tapes T,T are separated by a gap G formed therein by the cutting punch 14 holding their respective adjacent longitudinal edges Ta,Ta, plowed up away from each other, which gap G is sustained exactly by the physical dimensions of the cutting punch 14 particularly as regards the 'width thereof which defines a minimum required opening of the gap G, thereby eliminating the necessity of any added special separating device and assuring a fool-proof cutting of the elements E without the fear of damaging the tape fabric.

Designated at the reference numeral 18 is a cutter diagrammatically shown in FIGS. 8 and 9 for cutting the fastener chain F into individual fastener length after the chain F has been provided therein with an element-free gap Ga. The construction and operation of the cutter 18 is conventional and hence will require no further explanation. The gap producing apparatus 10 thus constructed operates in the following manner. The fastener chain F is first split at its leading end Fa along the opposed stringer edges Ta,Ta, without disengaging the interengaged row of fastener elements E, by feeding the chain F horizontally through the apparatus in the direction of the arrow indicated in FIG. 8 and in the manner depicted in FIG. 5. The chain F is thus moved, a predetermined distance until the desired location of an element-free gap to be produced arrives at the cutting punch 14, whereupon the punch 14 is actuated to cut a group of elements E along a length of the chain F corresponding to the element-free gap Ga to be formed or the length L of the punch 14. This cutting operation is depicted in FIG. 7, wherein the cutting punch 14 moves vertically down into the opening 16 and in so doing cuts the group of elements E centrally thereof and removes them from the chain F into the opening 16 which may be conveniently communicated to a collecting basket not shown.

The punch 14 is then retracted into a raised position as defined in FIG. 4 is particular and the fastener chain F having thus formed therein the element-free gap Ga is simply continued to move until the desired location for the next gap Ga is registered with the cutting punch 14.

There is shown in FIG. 1 1 a modified form of apparatus according to the invention which is characterized by the provision of an auxiliary cutter 19 attached to the main cutting punch 14 for forming a side indent Gb additionally in the region of the element-free gap Ga as shown in FIG. 10, which is adaptable for attaching the fastener chain F to trouser flies or the like. The auxiliary cutter 19 has its tapered blade tip 19a normally positioned short of the operating end 14b of the punch 14 and above the lower end 12a of the punch block 12, so that it does not come into contact with deflected edges Ta,Ta of the tapes T,T during the separation thereof.

What is claimed is:

1. An apparatus for producing fastener-element-free gaps in a continuous slide fastener chain having a pair of oppositely disposed stringer tapes carrying along their adjacent longitudinal edges two rows of interlocking fastener elements, the coupling parts of which elements on the one stringer tape extend into the longitudinal edge region of the other stringer tape when the fastener is closed, said apparatus comprising a punch block, a cutting punch reciprocally movable therein, and a die block positioned in oppositely spaced relation to said punch block and having a recess for receiving a group of fastener elements to be severed and an opening formed centrally of said recess for receiving said cutting punch during the downward stroke thereof in which said group of fastener elements is severed, said cutting punch having an upward stroke limited such that the distance between an extreme operating end of said punch and the bottom surface of said recess is smaller than the overall thickness of said fastener chain but larger than the thickness of said fastener elements.

2. The apparatus as defined in claim 1 which further includes an auxiliary cutter attached to said cutting punch, said cutter having a bladed tip end situated up above the lower end of said punch block when said cutting punch is held in retracted position.