US3121928A

US3121928A - Interlocking element for a concealed slide fastener

Info

Publication number: US3121928A
Application number: US119938A
Authority: US
Inventors: Takamatsu Ikuo
Original assignee: Yoshida Kogyo KK
Current assignee: YKK Corp
Priority date: 1960-11-26
Filing date: 1961-06-27
Publication date: 1964-02-25
Anticipated expiration: 1981-02-25

Description

Feb. 25, 1964 IKUO TAKAMATSU 3,121,928

INTERLOCKING ELEMENT FOR A CONCEALED SLIDE FASTENER Filed June 27, 1961 FIG. 2

United States Patent 3,121,923 INTERLGCKING ELEMENT FOR A CQNCEALED SLEDE FASTENER Ikuo Takamatsu, Uozn-shi, Japan, assignor to Yoshida Kogyo K.K., Tokyo, Japan, a corporation of Japan Filed June 27, 1%1, Ser. No. 11%,938 Cla ms priority, application Japan Nov. 26, 1960 4- Qlaims. (Cl. 24--2t 5.1)

The present invention relates to interlocking elements for concealed slide fasteners and has for its object to provide improved interlocking elements of the kind which enable smooth operation of a slider member for opening and closing the slide fastener, eliminating any danger of binding or jamming trouble of the slider member during operation.

In operation of conventional slide fasteners and particularly those of the concealed type, the slider member has often been subject to such trouble rendering the operation of the slide fastener diflicult or even completely impossible. This deficiency of previous concealed slide fasteners has effectively been overcome by the present invention as will be made apparent hereinafter.

Description will now be made with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of an embodiment of the interlocking element according to the present invention;

FIG. 2 is a fragmentary transverse cross section of a concealed slide fastener fitted with interlocking elements one of which is shown in FIG. 1, taken through a slider member interengaging the interlocking elements on cooperating fastener strips of the slide fastener; and

FIG. 3 is a perspective View of the concealed slide fastener attached to a fabric cloth and shown in closed state.

With concealed slide fasteners, the interlocking elements are set in a row along the folded braided edges of the respective base strips of the slide fastener. A slider member slidably embraces opposing interlocking elements. Usually, the body of the slider member has its opposite edge portions extending toward each other along the respective base strips secured to a fabric. Such edge portions are each more or less jammed between the adjacent row of interlocking elements on one hand and the associated base strip integral with the folded fabric edge on the other hand. Such slider member cannot be operated smoothly, as will be readily understood. This is particularly true when the fabric carrying the slide fastener has an overlapped joint perpendicular to the length thereof, for example as illustrated in FIG. 3. In case where the slide fastener is secured to a thick fabric or the row of interlocking elements is arranged to extend in a curved line according to the configuration of a garment or the like, operation of the slider member has been extremely diflicult and sometimes completely impossible.

Referring now particularly to FIG. 3, there is shown a concealed slide fastener which is stitched onto a fabric 5 along the adjoining edges thereof which are each folded back on themselves. The slide fastener comprises a pair of base strips or fastener tapes 4, a pair of rows 9 of interlocking elements formed according to the present invention and secured to the bent edge of the respective base tapes 4, and a slider member such as indicated at 7 in FIG. 2 (not shown in FIG. 3). The interlockng elements 1 each comprise a stem portion In, an interengaging tooth portion 1b and an arcuately curved leg portion 2 integral therewith that firmly embraces a core braid 8 formed along the extreme edge of the associated base strip 4 as shown in FIG. 2. According to the invention the outer surface of the arcuately curved leg porton 2 defines a smooth curve and at the free extremity of the curved leg portion 2 an integral projection 3 is formed extending a substantial distance outwardly and substantially perpendicularly to the general plane of the base strip 4 and terminating in a rounded outer end as shown in FIG. 2.

The slider member 7, as shown in cross section in FIG. 2, has its opposite edge portions 6 interposed between the row 9 of the interlocking elements 1 and the associated base strip 4, as with any or" conventional concealed slide fastener and has its inner surface defined by angularly intersecting linear surfaces. It will also be observed, however, that the outwardly extending projection 3 on each of the interlocking elements defines a space C between the upper surface, as viewed in FIG. 2, of the row 9 of interlocking elements 1 and the lower surface of the associated base strip 4 along the entire length of the row 9 of the interlocking elements. It will be appreciated that the space C forms a clearance or passageway through which the convexly curved outer surface of the adjacent edge portion 6 of the slider member '7 can pass freely thereby ensuring free and smooth sliding movement of the slider member over the mating rows 9 of interlocking elements even where the fabric 5 is thick or the rows 9 of interlocking elements extend in a curved line conforming to the configuration of fabric garment or the like to which the slide fastener is secured, irrespective of whether the fabric has an overlapped joint extending perpendicularly to the length of the slide fastener as indicated at 10 in FIG. 3 or not. With such jointed fabric, it will be seen that the slide fastener has its rows 9 of interlocking elements juxtaposed to six plies of fabric over the width B of the joint 10. It is very importarit that with projections 3 formed on respective interlocking elements 1 of the slide fastener the slider member can be operated smoothly lengthwise of the slide fastener not only over the extent A which is free of such joint 1-9 but also over the extent B corresponding to the width thereof. Furthermore, as will readily be observed in FIG. 2, the interlocking element is so dimensioned relative to the slider member '7 that the projection 3 is engaged by the adjacent edge portion 6 of the slider member to serve as a guide therefor in sliding movement thereof enabling free and smooth operation of the slider member together with the formation of said space be tween the interlocking element and the base strip.

The present invention thus provides interlocking elements for slide fasteners which enable smooth and light operation of the slider member at all times completely eliminating any jamming or like trouble involved with concealed slide fasteners having conventional interlocking elements while at the same time making it possible freely to use a concealed slide fastener with thicker fabrics or curved portions of a garment or the like.

What is claimed is:

1. In a concealed slide fastener comprising a pair of flexible base strips, a plurality of interlocking elements disposed along an edge of each of said strips and a slider for engaging and disengaging the interlocking elements on one strip with those on the other, the improvement comprising each of said elements being generally J-shaped with a stern portion, an integral interengaging tooth portion at one end of said stem portion and an integral curved leg portion at the opposite end of the stem portion, said leg portion curving back over said stem portion and gripping an edge portion of the respective base strip between said leg portion and stem portion, said leg por tion being formed at its free end with an integral bulbous head portion of approximately elliptical shape with its major axis disposed transversely of the adjacent part of said leg portion and with an outer portion extending outwardly from said leg in a direction away from said stern portion and having a rounded surface over which said base strip is bent, said outer portion positioning a body portion of said base strip away from the outer surface of said leg portion to provide a predetermined space for the free sliding movement of said slider.

2. A concealed slide fastener comprising a pair of flexible base strips, a plurality of interlocking elements disposed along an edge of each of said strips and a slider for engaging and disengaging the interlocking elements on one strip with those on the other strip, each of said elements being generally J-shaped with a stem portion, an integral interengaging tooth portion at one end of said stem portion and an integral curved leg portion at the opposite end of said stem portion, said leg portion curving back over said stem portion and gripping an edge portion of the respective base strip between said leg portion and stem portion, said leg portion being formed at its free end with an integral enlarged head portion of approximately elliptical shape with its major axis disposed transversely of the adjacent part of said leg portion and with an outer portion which extends outwardly from said leg in a direction away from said stem portion and has a side surface approximately perpendicular to the adjacent part of said leg and a rounded outer surface over which said base strip is bent, said head por tion spacing a body portion of said base strip away from the outer surface of said leg portion to provide a predetermined space to receive a portion of said slider which extends around said element and engages said side surface of said head portion.

3. In a concealed slide fastener comprising a pair of flexible base strips, a plurality of interlocking elements disposed along an edge of each of said strips and a slider for engaging and disengaging the interlocking elements on one strip with those on the other, the improvement comprising each of said elements being generally J-shaped with a stem portion, an integral interengaging tooth portion at one end of said stem portion and an integral curved leg portion curving back over said stem portion and gripping an edge portion of the respective base strip between said leg portion and stem portion, said leg portion being formed at its free end with an enlarged head of approximately elliptical shape with its major axis disposed transversely of the adjacent part of said leg portion and having a smaller inner portion projecting inwardly toward said stem portion and coacting with said stern portion to grip said edge portion of the base strip securely and a larger outer portion extending outwardly from said leg in a direction away from said stem portion and having a side surface approximately perpendicular to the adjacent part of said leg and a curved outer surface over which said base strip is flexed so that a body portion of said base strip is approximately parallel to said stern portion, said outer portion of said head spacing said body portion of the base strip away from the outer surface of said leg portion to provide a predetermined space for free movement of said slider.

4. A concealed slide fastener according to claim 3, in which said edge portion of the base strip which is gripped between said curved leg portions and stem portions of said interlocking elements comprises a core braid formed along the extreme edge of said base strip.

References Cited in the file of this patent UNITED STATES PATENTS 2,068,939 Winterhalter Jan. 26, 1937 2,263,651 Silberman Nov. 25, 1941 2,888,727 Heimberger June 2, 1959 2,991,527 McNamara June 11, 1961 FOREIGN PATENTS 489,657 Great Britain Aug. 2, 1938 1,035,786 France Aug. 31, 1953 201,777 Australia July 16, 1959

Claims

1. IN A CONCEALED SLIDE FASTENER COMPRISING A PAIR OF FLEXIBLE BASE STRIPS, A PLURALITY OF INTERLOCKING ELEMENTS DISPOSED ALONG AN EDGE OF EACH OF SAID STRIPS AND A SLIDER FOR ENGAGING AND DISENGAGING THE INTERLOCKING ELEMENTS ON ONE STRIP WITH THOSE ON THE OTHER, THE IMPROVEMENT COMPRISING EACH OF SAID ELEMENTS BEING GENERALLY J-SHAPED WITH A STEM PORTION, AN INTEGRAL INTERENGAGING TOOTH PORTION AT ONE END OF SAID STEM PORTION AND AN INTEGRAL CURVED LEG PORTION AT THE OPPOSITE END OF THE STEM PORTION, SAID LEG PORTION CURVING BACK OVER SAID STEM PORTION AND GRIPPING AN EDGE PORTION OF THE RESPECTIVE BASE STRIP BETWEEN SAID LEG PORTION AND STEM PORTION, SAID LEG PORTION BEING FORMED AT ITS FREE END WITH AN INTEGRAL BULBOUS HEAD PORTION OF APPROXIMATELY ELLIPTICAL SHAPE WITH ITS MAJOR AXIS DISPOSED TRANSVERSELY OF THE ADJACENT PART OF SAID LEG PORTION AND WITH AN OUTER PORTION EXTENDING OUTWARDLY FROM SAID LEG IN A DIRECTION AWAY FROM SAID STEM PORTION AND HAVING A ROUNDED SURFACE OVER WHICH SAID BASE STRIP IS BENT, SAID OUTER PORTION POSITIONING A BODY PORTION OF SAID BASE STRIP AWAY FROM THE OUTER SURFACE OF SAID LEG PORTION TO PROVIDE A PREDETERMINED SPACE FOR THE FREE SLIDING MOVEMENT OF SAID SLIDER.