EP3045068B1

EP3045068B1 - Fastener chain, slide fastener, and fastener element manufacturing method

Info

Publication number: EP3045068B1
Application number: EP13892872.6A
Authority: EP
Inventors: Hayato Ishii; Futoshi Kozato; Tsutomu Saito; Masamichi YAMAGATA; Engelhardt DIRK; Reinke GUNTHER
Original assignee: YKK Corp
Current assignee: YKK Corp
Priority date: 2013-09-09
Filing date: 2013-09-09
Publication date: 2020-10-07
Anticipated expiration: 2033-09-09
Also published as: WO2015033475A1; EP3045068A4; JP6161708B2; EP3045068A1; CN105530828A; JPWO2015033475A1

Description

Technical Field

The present invention relates to a fastener chain having fastener elements, of which leg portions are curved relative to a tape width direction, and to a slide fastener and a method of manufacturing the fastener element.

Background Art

In general, a metal fastener element includes an engaging head portion, a body portion extending from the engaging head portion in one direction (rearward), and a pair of right and left leg portions extending to be bifurcated from the body portion in one direction (rearward). Also, the engaging head portion is provided with an engaging protrusion portion and an engaging recess portion or fitting space portion configured to allow an engaging protrusion portion of the mating fastener element to be fitted therein.
As types of metal elements, a so-called single-side type fastener element (hereinafter, simply referred to as a single-side element), in which an engaging protrusion portion is provided on one surface (upper surface) of an engaging head portion and an engaging recess portion is provided on the other surface (lower surface) of the engaging head portion, and a so called double-side type fastener element (hereinafter, simply referred to as a double-side element), in which an engaging protrusion portion and a fitting space portion are provided as one set on each of both upper and lower surface of an engaging head portion, are known.
As an example of the single-side metal element, for example, a fastener element disclosed in WO 2013/027281 A1 is known. Also, as an example of the double-side metal element, for example, a fastener element according to the preamble of claim 1 is disclosed in WO 2010/089854 A1 . Another fastener chain is disclosed in WO 2010/100744 A1 . GB442809 discloses a fastener with curved fastener elements.
However, in general, the engaging head portion, the body portion and the leg portions of the metal fastener element are often straightly arranged along a tape width direction (to be parallel to the tape width direction), when viewing a fastener stringer, which has a plurality of fastener elements attached on a fastener tape, from a tape front or back side of the fastener tape.
Meanwhile, a slide fastener is also known, in which a portion of a fastener element is bent or curved relative to a tape width direction, as viewed from a tape front or back side of a fastener tape, for example, for the purpose of engaging right and left element rows with each other regardless of engaging protrusion portions or engaging recess portions (or fitting space portions) or providing an exterior appearance different from other articles to achieve differentiation, or for other reasons. Actually, examples of such a slide fastener are disclosed in U.S. Pat. Nos. 1,864,614 (Patent Document 3) and 2,158,079 (Patent Document 4).
For example, a fastener element described in Patent Document 3 has an engaging head portion, a body portion and a pair of leg portions. The engaging head portion of Patent Document 3 is not provided with an engaging protrusion portion or an engaging recess portion (or fitting space portion) intended to be engaged with the mating fastener element. Instead, the engaging head portion is provided to be inclined relative to the leg portions and the body portion of the fastener element arranged to be parallel to the tape width direction, as viewed from the tape front or back side, so that when the slide fastener is constructed, right and left element rows can be engaged with each other to close the slide fastener.
Also, in Patent Document 4, a fastener element having an engaging head portion and a pair of leg portions or a fastener element having an engaging head portion, a body portion and a pair of leg portions is described. The fastener elements are configured so that the engaging head portion or the engaging head portion and leg portions has a curved shape relative to a tape width direction as viewed from a tape front or back side.
Also, in the fastener elements of Patent Document 4, a rotation preventing means is provided to prevent one element row from being rotated toward the tape front or back side relative to the other element row in a state where right and left element rows are engaged with each other.

Prior Art Document

Patent Document

Patent Document 1: WO 2013/027281
Patent Document 2: WO 2010/089854
Patent Document 3: U.S. Pat. No. 1,864,614
Patent Document 4: U.S. Pat. No. 2,158,079

Summary of Invention

Problems to Be Solved by Invention

As in the fastener elements of Patent Documents 3 and 4, when an engaging head portion, which is a portion of a fastener element, is curved relative to a tape width direction as viewed from a tape front or back side, a slide fastener having such fastener elements has an exterior appearance different from slide fasteners having typical fastener elements in which an engaging head, a body portion and leg portions are arranged along the tape width direction, thereby achieving differentiation from other articles and thus enhancing a commercial value of the fastener article.
However, on the other hand, the slide fastener having fastener elements in which the engaging head portion is curved relative to the tape width direction causes reduction in engaging strength of right and left element rows, when being engaged with each other, due to the curved shape of the engaging head portion. Also, if the right and left element rows in the engaged state are pulled in a direction of separating the right and left element rows from each other or the right and left element rows in the engaged state are subjected of an external force in a tape front-and-back direction, the right and left element rows are disengaged from each other and thus the right and left fastener stringers are easily cracked. Accordingly, a lateral pulling strength or thrust strength of the fastener chain is reduced.
Therefore, in the slide fastener in which a portion of the fastener element is curved relative to the tape width direction as in Patent Document 3 and 4, there is a problem in that the slider fastener is likely not to sufficiently endure the use of articles employing the slide fastener (fastener-attached articles) depending on the articles.
The present invention has been made keeping in mind the above problems, and an detailed object thereof is to provide a fastener chain and a slide fastener, in which differentiation from other articles can be achieved by curving a portion of a fastener element relative to a tape width direction as viewed from a tape front or back side and also an engaging strength sufficient to endure the use of articles can be stably achieved when right and left element rows are engaged with each other, and also to provide a method of manufacturing a fastener element used in the fastener chain and the slide fastener.

Means for Solving Problems

In order to achieve the object, a fastener chain according to a first aspect provided by the present invention includes, as basic configurations, a pair of right and left fastener tapes and a pair of fastener stringers having a plurality of metal fastener elements crimped and attached on opposing tape side edge portions of the fastener tapes along a tape length direction, wherein each fastener element includes an engaging head portion, a body portion arranged on one end side of the engaging head portion and a pair of leg portions extending to be bifurcated from one end of the body portion, wherein the engaging head portion includes a head body having a first main surface and a second main surface opposite to the first main surface, an engaging protrusion portion provided to protrude from the first main surface of the head body and an engaging recess portion provided to be recessed in the second main surface of the head body; wherein the first and second main surfaces of the head body are flat surfaces perpendicular to the tape length direction; and wherein the pair of leg portions extend to be curved in a direction oblique to the first and second main surfaces of the head body.
In particular, in the fastener chain of the present invention, the pair of leg portions are preferably formed to be curved relative to the first and second main surfaces of the head body in a protruding direction of the engaging protrusion portion.
Also, a fastener chain according to a second aspect provided by the present invention includes, as basic configurations, a pair of right and left fastener tapes and a pair of fastener stringers having a plurality of metal fastener elements crimped and attached on opposing tape side edge portions of the fastener tapes along a tape length direction, wherein each fastener element includes an engaging head portion, a body portion arranged on one end side of the engaging head portion and a pair of leg portions extending to be bifurcated from one end of the body portion, wherein the engaging head portion includes a head body having a first main surface and a second main surface opposite to the first main surface, engaging protrusion portions provided to protrude from the first and second main surfaces of the head body and fitting space portions arranged between the engaging protrusion portions and the body portion on the first and second main surfaces and configured to allow the mating engaging protrusion portion to be fitted therein; wherein the first and second main surfaces of the head body are flat surfaces perpendicular to the tape length direction; and wherein the pair of leg portions extend to be curved in a direction oblique to the first and second main surfaces of the head body.
In the fastener chain of the present invention as described above, preferably, first main surfaces of distal end portions of the leg portions, which are surfaces facing the same side as that in the first main surface of the engaging head portion, are arranged in a formation region of the head body of the engaging head portion of the mating fastener element in the tape length direction.
Also, in the fastener chain of the present invention, preferably, a ratio of an insertion depth, in the tape length direction, of the engaging protrusion portion, which is inserted in the engaging recess portion or fitting space portion of the mating fastener element, to a protruding dimension, in the tape length direction, of the engaging protrusion portion, which protrudes from the front main surface of the head body, is set to 65% or more and 85% or less.
Further, preferably, where a size of a distance between head bodies of adjacent fastener elements in one fastener stringer is a and a size of an insertion depth, in the tape length direction, of the engaging protrusion portion which is inserted in the engaging recess portion or fitting space portion of the mating fastener element is b, a value of b/a is set to 0.25 or more and 0.30 or less.
Also, preferably, first main surfaces of the leg portions have, on distal end portions of the leg portions, chamfered surfaces parallel to the first and second surfaces of the head body.
Further, according to the present invention, there is provided a slide fastener constructed by attaching a slider on the element rows formed by the plurality of fastener elements of the fastener chain having the configurations as described above, wherein the pair of leg portions are formed to be curved relative to the first and second main surfaces of the head body in a direction along which the slider is slid to engage the pair of fastener stringers with each other.
Preferably, the slide fastener of the present invention further includes a separable end stop having a separable pin fixed on a rear end portion of one fastener stringer and a retainer pin fixed on a rear end portion of the other fastener stringer, wherein a distance between leg portions of fastener elements arranged at the most rear ends of the element rows and the separable pin or retainer pin is gradually increased toward the distal end portions of the leg portions.
Further, according to the present invention, there is provided a method of manufacturing a fastener element including an engaging head portion, a body portion arranged on one end side of the engaging head portion and a pair of engaging protrusion portions extending to be bifurcated from one end of the body portion, wherein the engaging head portion includes a head body having a first main surface and a second main surface opposite to the first main surface, an engaging protrusion portion provided to protrude from the first main surface of the head body and an engaging recess portion provided to be recessed in a bottomed shape in the second main surface of the head body, the method including: forming the engaging protrusion portion and the engaging recess portion on a metal rectangular wire material by pressing; blanking a portion of the rectangular wire material having the engaging protrusion portion and the engaging recess portion formed thereon using a cutting die and a cutting punch to form the fastener element, wherein the cutting punch has, on a distal end thereof, a head-side flat portion having a flat surface to be abutted against the head body and a leg portion-forming portion curved in a direction oblique to the flat surface of the head-side flat portion; and curving the pair of leg portions in a direction oblique to the first and second main surfaces of the head body upon blanking of the fastener element.
In the manufacturing method of the present invention, preferably, the cutting punch further includes a receiving recess portion provided to be recessed in the head-side flat portion and thus to receive the engaging protrusion portion or an inserting protrusion portion provided to protrude from the head-side flat portion and thus to be inserted in the engaging recess portion.
Also, in the manufacturing method of the present invention, preferably, upon blacking of the fastener element, after blanking is initiated by bringing the head-side flat portion in contact with the rectangular wire material, the leg portion-forming portion is brought in contact with the rectangular wire material so that the pair of leg portions are curved.
Further, preferably, the manufacturing method of the present invention further includes providing a surface, which is curved relative to the flat surface of the head-side flat portion in a direction opposite to a blanking direction, on the leg portion-forming portion; and providing a chamfered portion-forming portion, which has a surface parallel to the flat surface of the head-side flat portion, at a location on the cutting die corresponding to the distal end portions of the leg portions of the fastener element.

Advantageous Effects of Invention

The fastener chain according to the first aspect of the present invention is a fastener chain having a pair of fastener stringers having so-called single-side metal elements crimped and attached on opposing tape side edge portions of a pair of right and left fastener tapes, in wherein the first and second main surfaces of the head body of each fastener element are flat surfaces perpendicular to the tape length direction and the pair of leg portions extend to be curved in a direction oblique to the first and second main surfaces of the head body.
In this way, the fastener chain having the single-side metal fastener elements, of which leg portions are curved relative to a tape width direction, has an exterior appearance different from convention typical fastener elements, in which an engaging head portion, a body portion and leg portion of a fastener element are arranged along the tape width direction, and thus can be differentiated from other articles. Accordingly, it is possible to easily enhance a commercial value of fastener-attached articles employing the fastener chain.
Further, in the fastener chain of the present invention, the first and second main surfaces of the head body of each fastener element are arranged to be parallel to each other in the tape width direction, the engaging protrusion portion is provided to protrude from the first main surface of the head body, and also the engaging recess portion having a bottomed shape is provided to be recessed in the second main surface of the head body. Accordingly, the right and left element rows can be stably engaged with each other and disengaged from each other, and also a lateral pulling strength and a thrust strength equal to or higher than those of conventional typical fastener chains can be stably achieved.
Further, in the fastener chain of the present invention, the pair of leg portions are crimped and fixed on the fastener tape while being curved in a direction oblique to the tape width direction. Accordingly, the fastener element can be hardly inclined forward or rearward in the tape length direction and thus a posture of the fastener element can be stably maintained. Therefore, when a slide fastener is constructed by the fastener chain, the right and left element rows can be smoothly engaged with each other and disengaged from each other and also a good slidability of a slider can be stably achieved.
Also, because the pair of leg portions of the fastener element are fixed on the fastener tape while being curved in a direction oblique to the tape width direction, a contact area between the pair of leg portions and the tape side edge portion of the fastener tape is increased. Thus, it is expected that an attaching strength of the fastener element on the fastener tape can be enhanced.
Meanwhile, according to the present invention, first and second main surfaces of the body portion of the fastener element may have only flat surfaces perpendicular to the tape length direction like the first and second main surfaces of the head body, only curved surfaces connected to first and main surfaces of the leg portions, or both flat surfaces and curved surfaces.
In the fastener chain of the present invention, the pair of leg portions are formed to be obliquely curved relative to the first and second main surfaces of the head body in a protruding direction of the engaging protrusion portion.
Typically, in slide fasteners having single-side metal elements, in order to smoothly engage and disengage right and left element rows with and from each other, an engaging protrusion portion of each single-side element are configured to protrude from the head body in a sliding direction of a slider for closing the slide fastener. In other words, when the single-side elements have been moved into an element guide passage of the slider, the engaging protrusion portions are arranged to protrude toward shoulder mouths of the slider, not a rear mouth thereof. Also, in general, single-side elements moved to the vicinity of the rear mouth of the slider are hardly misaligned in position relative to the slider because right and left element rows have been engaged with each other, but single-side elements moved to the vicinity of the shoulder mouths of the slider can be relatively freely moved and thus tend to be easily misaligned in position relative to the slider.
Accordingly, when the slide fastener is constructed and then the slider is slid in the fastener-closing direction, single-side elements moved into the element guide passage from the shoulder mouths of the slider are likely to be moved at the vicinity of the shoulder mouths so that the leg portions of the single-side elements come in contact with the slider. In this case, when a pair of leg portions of each single-side element are curved toward the shoulder mouths like the protruding direction of the engaging protrusion portion, the leg portions of the single-side element can hardly damage the slider even if the leg portions of the single-side element come in contact with the slider.
On the other hand, when the slider is slid in a fastener-opening direction, single-side elements moved into the element guide passage from the rear mouth of the slider are hardly moved at the vicinity of the rear mouth. Accordingly, even when the pair of leg portions of each single-side element are curved as described above, the leg portions of the single-side element can hardly damage the slider.
Next, the fastener chain according to the second aspect of the present invention is a fastener chain having a pair of fastener stringers having so-called double-side metal elements crimped and attached on opposing tape side edge portions of a pair of right and left fastener tapes, in wherein the first and second main surfaces of the head body of each fastener element are flat surfaces perpendicular to the tape length direction and the pair of leg portions extend to be obliquely curved relative to the first and second main surfaces of the head body in a protruding direction of one engaging protrusion portion .
Like the fastener chain according to the first aspect, the fastener chain according to the second aspect can be differentiated from convention typical fastener elements, in which an engaging head portion, a body portion and leg portion of a fastener element are arranged along the tape width direction. Accordingly, it is possible to easily enhance a commercial value of fastener-attached articles employing the fastener chain. Further, the right and left element rows can be stably engaged with each other and disengaged from each other, and also a lateral pulling strength and a thrust strength equal to or higher than those of conventional typical fastener chains can be stably achieved.
Also, because the pair of leg portions are crimped and fixed on the fastener tape while being curved in a direction oblique to the tape width direction, the fastener element can be hardly inclined forward or rearward in the tape length direction and thus a posture of the fastener element can be stably maintained. Therefore, when a slide fastener is constructed by the fastener chain, the right and left element rows can be smoothly engaged with each other and disengaged from each other and also a good slidability of a slider can be stably achieved. In addition, because a contact area between the pair of leg portions of the fastener element and the tape side edge portion of the fastener tape is increased, it is expected that an attaching strength of the fastener element on the fastener tape can be enhanced.
In the fastener chain of the present invention according to the first and second aspects as described above, first main surfaces of distal end portions of the leg portions, which are surfaces facing the same side as that in the first main surface of the engaging head portion, are arranged in a formation region of the head body of the engaging head portion of the mating fastener element in the tape length direction. Accordingly, an attaching strength of the fastener element on the fastener tape can be appropriately achieved. Also, the leg portions can be prevented from being excessively elongated to reduce flexibility of the fastener chain, and thus an appropriate flexibility can be stably achieved.
Also, in the fastener chain of the present invention, a ratio of an insertion depth, in the tape length direction, of the engaging protrusion portion, which is inserted in the engaging recess portion or fitting space portion of the mating fastener element, to a protruding dimension, in the tape length direction, of the engaging protrusion portion, which protrudes from the front main surface of the head body, is set to 65% or more and 85% or less, preferably 70% or more and 80% or less.
Because the ratio of the insertion depth to the protruding dimension of the engaging protrusion portion is set to 65% or more, an engaging strength of the fastener chain can be enhanced and thus a desired lateral pulling strength or thrust strength which can endure the use of fastener-attached articles can be stably achieved. Further, because the ratio of the insertion depth to the protruding dimension of the engaging protrusion portion is set to 85% or less, it is possible to prevent engagement of the right and left element rows from becoming excessively strong. Accordingly, an appropriate flexibility of the fastener chain can be stably achieved. Also, it is possible to prevent slidability of a slider from being reduced when a slide fastener is constructed.
Further, in the fastener chain of the present invention, where a size of a distance between head bodies of adjacent fastener elements in one fastener stringer is a and a size of an insertion depth, in the tape length direction, of the engaging protrusion portion which is inserted in the engaging recess portion or fitting space portion of the mating fastener element is b, a value of b/a is set to 0.25 or more and 0.30 or less.
Because the value of b/a is set to 0.25 or more, an engaging strength of the fastener chain can be enhanced and thus a desired lateral pulling strength or thrust strength which can endure the use of fastener-attached articles can be stably achieved. Also, because the value of b/a is set to 030 or less, an appropriate flexibility of the fastener chain can be stably achieved.
Further, in the fastener chain of the present invention, because first main surfaces of the leg portions have, on distal end portions of the leg portions, chamfered surfaces parallel to the first and second surfaces of the head body, a good hand feeling or skin feeling to the fastener element can be obtained. Also, when the slide fastener is constructed and then the slider is slid in the fastener-closing direction, the leg portions of the fastener element can further hardly damage the slider.
Further, according to the present invention, there is provided a slide fastener constructed using the fastener chain having the configurations as described above, in which the pair of leg portions of the fastener element are formed to be curved relative to the first and second main surfaces of the head body in a direction along which the slider is slid to engage the fastener rows with each other.
The slide fastener can be easily differentiated from convention typical slide fastener, in which an engaging head portion, a body portion and leg portion of a fastener element are arranged along the tape width direction. Accordingly, it is possible to easily enhance a commercial value of fastener-attached articles employing the slide fastener. Further, the right and left element rows can be stably engaged with each other and disengaged from each other by sliding the slider. In addition, an engaging strength equal to or higher than those of conventional typical slide fasteners can be stably achieved.
Also, because the pair of leg portions are crimped and fixed on the fastener tape while being curved in a direction oblique to the tape width direction, the fastener element can be hardly inclined forward or rearward in the tape length direction and thus a posture of the fastener element can be stably maintained. Therefore, the right and left element rows can be smoothly engaged with each other and disengaged from each other by sliding the slider, and also a good slidability of the slider can be stably achieved.
The slide fastener of the present invention further includes a separable end stop having a separable pin fixed on a rear end portion of one fastener stringer and a retainer pin fixed on a rear end portion of the other fastener stringer, in which a distance between leg portions of fastener elements arranged at the most rear ends of the element rows and the separable pin or retainer pin is gradually increased toward the distal end portions of the leg portions.
Accordingly, a partial flexibility of the fastener stringer between the fastener elements and the separable pin or retainer pin can be enhanced, and thus a direction of the separable pin or retainer pin can be easily inclined in the tape width direction relative to the element rows. Therefore, an operation of inserting the separable pin into a retainer box through the element guide passage of the slider or an operation of removing the separable pin from the retainer box through the element guide passage of the slider can be more smoothly performed. Thus, operability of the separable end stop can be enhanced.
In addition, the method of manufacturing the single-side metal element according to the present invention includes forming the engaging protrusion portion and the engaging recess portion on a metal rectangular wire material by pressing; blanking a portion of the rectangular wire material using a cutting die and a cutting punch to form the fastener element, wherein the cutting punch has, on a distal end thereof, a head-side flat portion having a flat surface and a leg portion-forming portion curved in a direction oblique to the flat surface; and curving the pair of leg portions in a direction oblique to the first and second main surfaces of the head body upon blanking of the fastener element.
According to the manufacturing method of the present invention, single-side elements, in which first and second main surfaces of a head body are flat surfaces perpendicular to the tape length direction and a pair of leg portions extend to be curved in a direction oblique to the first and second main surfaces of the head body can be stably and continuously manufactured.
In particular, in the manufacturing method of the present invention, the cutting punch used to blank the fastener element further includes a receiving recess portion provided to be recessed in the head-side flat portion and thus to receive the engaging protrusion portion or an inserting protrusion portion provided to protrude from the head-side flat portion and thus to be inserted in the engaging recess portion. Accordingly, because upon blanking of the fastener element, a shape of the engaging protrusion portion or engaging recess portion can be easily maintained, signal-side elements in which the engaging protrusion portion or engaging recess portion has a predetermined shape can be stably manufactured.
Further, in the manufacturing method of the present invention, upon blacking of the fastener element, after blanking is initiated by bringing the head-side flat portion in contact with the rectangular wire material, the leg portion-forming portion is brought in contact with the rectangular wire material so that the pair of leg portions are curved. Accordingly, while the fastener element is blanked by the cutting punch, the leg portions of the fastener element can be smoothly and stably plastically deformed to be obliquely curved relative to the first and second main surfaces of the head body.
In addition, the manufacturing method of the present invention further includes providing a surface, which is curved relative to the flat surface of the head-side flat portion in a direction opposite to a blanking direction, on the leg portion-forming portion; and providing a chamfered portion-forming portion, which has a surface parallel to the flat surface of the head-side flat portion, at a location on the cutting die corresponding to the distal end portions of the leg portions of the fastener element. Accordingly, upon blanking of the fastener element, chamfered portions (chamfered surfaces) having a surface parallel to the first and second surfaces of the head body can be smoothly and stably formed on distal end portions of the leg portions respectively.

Brief Description of Drawings

Fig. 1 is a plan view showing a slide fastener constructed using a fastener chain according to an embodiment 1 of the present invention.
Fig. 2 is a perspective view showing a fastener element of the slide fastener.
Fig. 3 is a front view of the fastener element as viewed from a side thereof on which engaging protrusion portions in a tape length direction are arranged.
Fig. 4 is a side view of the fastener element as viewed in a tape width direction.
Fig. 5 is a partial sectional view explaining an engaged state of right and left fastener elements in the slide fastener, sectionally illustrating a part of element rows.
Fig. 6 is a sectional view showing a relationship between right and left element rows and a slider.
Fig. 7 is an explanatory view explaining a relationship between the right and left element rows and a separable end stop.
Fig. 8 is a sectional view explaining a step of forming an engaging protrusion portion and an engaging recess portion upon manufacturing of the fastener element.
Fig. 9 is a sectional view explaining a step of blanking a fastener element upon manufacturing of the fastener element.
Fig. 10 is a sectional view explaining a step of blanking a fastener element upon manufacturing of the fastener element according to another aspect.
Fig 11 is a front view of a fastener element used for a fastener chain according to an embodiment 2 of the present invention, as viewed in a tape length direction.
Fig. 12 is a sectional view of the fastener element.

Embodiments of Invention

Hereinafter, exemplary embodiments of the present invention will be described in detail by way of example with reference to the accompanying drawings. Meanwhile, the present inventions is not limited to the following embodiments and thus various modifications thereof can be made so long as having substantially the same configurations as those of the present invention and also achieving the same effects as those thereof.
For example, although a slide fastener according to an embodiment 1 as described below is configured so that a separable end stop is arranged on a lower end of a fastener chain to be connected to right and left element rows, the present invention may be configured so that a bottom stop is provided instead of the separable end stop.

Embodiment 1

Fig. 1 is a plane view showing a slide fastener constructed using a fastener chain according to the present embodiment 1. Figs. 2, 3 and 4 are a perspective view, a front view and a side view, respectively, showing a fastener element of the slide fastener.
Meanwhile, in the following description, a front and rear direction refers to a tape length direction of a fastener tape corresponding to a sliding direction of a slider. In particular, a front direction refers to a direction along which the slider is slid to engage right and element rows with each other and thus to close the slide fastener, and a rear direction refers to a direction along which the slider is slid to disengage the right and left element rows from each other and thus to open the slide fastener.
A right and left direction refers to a tape width direction of the fastener tape, corresponding to a direction which is parallel to a tape surface of the fastener tape and perpendicular to the tape length direction. Also, an upward and downward direction refers to a tape back and rear direction perpendicular to the tape surface of the fastener tape, and in particular, a direction, toward which a pull tab of the slider is arranged relative to the fastener tape, is referred to as an upward direction and a direction opposite thereto is referred to as a downward direction.
The slide fastener 1 of the present embodiment 1 includes a pair of right and left fastener stringers 10 having element rows 12 respectively formed on tape side edge portions of right and left fastener tapes 11, a slider 30 arranged to be slidable along the element rows 12, top stops arranged adjacent to front ends of the element rows 12 to prevent the slider 30 from falling out, and a separable end stop 6 arranged adjacent to rear ends of the element rows 12.
Meanwhile, the essential features in the slide fastener 1 of the present invention are configurations of a fastener element 20 forming the element rows 12, and thus for example, the slider 30, the top stops 5 and the separable end stop 6 have substantially the same configurations as those of a slider, top stops and a separable end stop used in a slide fastener having conventional single-side metal elements as generally well known.
For example, the slider 30 of the present embodiment 1 includes a slider body 31 and a pull tab 32 pivotally held on the slider body 31. Also, the slider body 31 has upper and lower blades 33 and 34, a guide post 35 for connecting front end portions of the upper and lower blades 33 and 34 (end portions thereof located toward shoulder mouths), right and left flange portions 36 arranged on right and left side edge portions of the upper and lower blades 33 and 34, and a pull tab attaching post 37 erected on an upper surface of the upper blade 33 for holding the pull tab 32.
Right and left shoulder mouths are formed on a front end of the slider body 31 with the guide post 35 interposed therebetween, and also a rear mouth is formed on a rear end of the slider body 31. Also, a generally Y-shaped element guide passage is formed between the upper and lower blades 33 and 34 to communicate the right and left shoulder mouths with the rear mouth. Further, in the slider body 31, tape insertion gaps for allowing right and left fastener tapes 11 to be inserted therethrough are respectively formed between right and left upper flange portions 36, which are arranged on the upper blade 33, and right and left lower flange portions 36, which are arranged on the lower blade 34.
The separable end stop 6 of the present embodiment 1 has a separable pin 7 fixed on a rear end portion of the left fastener stringer 10, a retainer pin 8 fixed on a rear end portion of the right fastener stringer 10 and a retainer box 9 arranged on a rear end portion of the retainer pin 8. Also, materials of the slider 30 and the separable end stop 6 are not particularly limited, and thus any materials may be used.
Each fastener stringer 10 of the present embodiment 1 is configured so that a plurality of metal fastener elements 20 are provided in a row at a predetermined pitch on a tape side edge portion of the respective fastener tape 11, and each element row 12 is formed by the plurality of fastener elements 20 attached on the respective fastener tape 11. Also, the fastener chain is constructed by engaging the right and left fastener stringers 10 with each other.
The fastener tape 11 is woven or knitted in a band shape and has a tape main body portion, which is an attaching portion on a fastener-attached article, and a tape side edge portion (also referred to as an element attaching portion) arranged along one side edge of the tape main body portion and intended to be provided with the plurality of fastener elements 20 in a row. Also, in the present embodiment 1, core string portions may be respectively provided on opposing tape side end edges of the right and left fastener tapes 11 to be swollen from tape front-and-back surfaces of the respective fastener tapes 11
The fastener element 20 of the present embodiment 1 is constructed of a metal, such as copper, copper alloy or aluminum alloy. As shown in Figs. 2 to 4, the fastener element 20 includes an engaging head portion 21 having an engaging protrusion portion 24 and an engaging recess portion 25, a body portion 22 extending from one end of the engaging head portion 21, and a pair of leg portions 23 extending to be bifurcated from one end of the body portion 22.
Also, the fastener element 20 is configured as a single side element in which the engage protrusion portion 24 and the engaging recess portion 25 are respectively arranged on opposite surfaces of the engaging head portion 21, and also is symmetrically formed with respect to the center position thereof in an element width direction (tape front-and-back direction).
Meanwhile, in Figs. 2 to 4, the fastener element 20 is shown in a form when the fastener element 20 has been attached on the fastener tape 11, but the fastener element 20 before being attached has a generally Y-shaped form in which the pair of leg portions 23 are spread from the body portion 22 in the element width direction.
The engaging head portion 21 of the present embodiment 1 includes a head body 21a having a constant size in element thickness dimension (dimension in the tape length direction) between a front surface (first main surface) and a rear surface (second main surface) thereof, the engaging protrusion portion 24 provided to protrude from the front surface of the head body 21 a in a mountain shape, and the engaging recess portion 25 having a bottom surface portion provided to be recessed in the rear surface of the head body 21a.
The front and rear surfaces of the head body 21a are formed on flat surfaces perpendicular to the tape length direction (flat surfaces parallel to each other in the tape width direction), and a dimension of the head body 21a in the tape length direction has a constant size. As shown in Fig. 5, the engaging protrusion portion 24 and the engaging recess portion 25 are arranged so that a position of the engaging protrusion portion 24 on the front surface of the head body 21a corresponds to a position of the engaging recess portion 25 on the rear surface of the head body 21a.
Further, in the present embodiment 1, a dimension in the tape length direction as measured from the front surface of the head body 21a to a distal end (vertex surface) of the engaging protrusion portion 24 (a height dimension of the engaging protrusion portion 24) and a dimension in the tape length direction as measured from the rear surface of the head portion 21 a to the bottom surface portion of the engaging protrusion portion 24 (a depth dimension of the engaging recess portion 25) are respectively set to predetermined sizes. In particular, the height dimension of the engaging recess portion 25 is sized so that a value of b/a as described below is within a predetermined range.
The body portion 22 of the present embodiment 1 is arranged to extend in the element length direction (tape width direction) from a position of an end edge of the engaging recess portion 25 to a position of a tape sandwiching surface 26 on a crotch portion from which the pair of leg portions 23 are branched. Namely, in the present embodiment 1, the body portion 22 refers to a portion arranged to extend in the element length direction from the position of the end edge of the engaging recess portion 25 to the position of the tape sandwiching surface 26 on the crotch portion, and thus a portion located more toward a tape outward side than the body portion 22 is referred to as the engaging head portion 21 and a portion located more toward a tape inward side than the body portion 22 is referred to as leg portions 23. Further, in the present embodiment 1, front and rear surfaces of the body portion 22 are respectively flushed with front and rear surfaced of the head body 21a. In addition, front and rear surfaces of the leg portions 23 as described below are formed as curved surfaces, but connected to the front and rear surfaces of the body portion 22.
The leg portions 23 of the present embodiment 1 extend from the body portion 22 toward the tape inward side, and hook-shaped bent portions 23a bent in a direction (inward direction) of approaching each other are respectively arranged on distal regions of the pair of leg portions 23 (end regions thereof on the tape inward side). Also, an inner peripheral surface defined by the body portion 22 and the pair of leg portions 23 is arranged to be parallel to the tape length direction, and the inner peripheral surface becomes the tape sandwiching surface 26 coming in close contact with the fastener tape 11.
Meanwhile, as used herein, the term "tape outward side" refers to a portion of the associated fastener element 20 located more outward than a tape end edge of the fastener tape 11, onto which the fastener element 20 is to be attached, as viewed in a plane of Fig. 1, and the term "tape inward side" refers to a portion of the associated fastener element 20 located more inward than the tape end edge of the fastener tape 11, onto which the fastener element 20 is to be attached, as viewed in the plane of Fig. 1.
Also, in the fastener element 20 of the present embodiment 1, as viewed in a plane of slide fastener 1, the pair of leg portions 23 extend to be curved in a direction oblique to the front and rear surfaces of the head body 21a (or relative to the tape width direction), so that distal end portions of the leg portions 23 are positioned more forward in a protruding direction of the engaging protrusion portion 24 than base end portions thereof (end portions located toward the body portion 22).
In this case, front surfaces of portions of the leg portions 23, except the distal end portions, are formed as curved surfaces concavely curved to be located more forward as going toward distal ends (tape inward sides) of the leg portions 23. Also, rear surfaces of the leg portions 23 are formed as curved surfaces convexly curved to be located more forward as going toward distal ends (tape inward sides) of the leg portions 23. Further, thickness dimensions (dimensions in the tape length directions) of the portions of the leg portions 23, except the distal end portions, have generally substantially constant sizes.
Alternatively, although in the present embodiment 1, the pair of leg portions 23 extend to be curved as described above, the pair of leg portions of the present invention may extend to be linearly inclined in a direction oblique to the tape width direction so that the distal end portions of the leg portions are located more forward than the base end portions.
The front surfaces of the distal end portions of the leg portions 23 of the present embodiment 1 are respectively provided with chamfered portions 23b for the purpose of providing a good hand feeling or skin feeling to the fastener element 20 or causing the fastener element 20 to be hardly caught on the slider 30 upon sliding of the slider 30. The chamfered portions 23b are constructed by surfaces parallel to the front and rear surfaces of the head body 21a.
In this case, the curved shape of the leg portions 23 is formed so that positions of front surfaces of the distal end portions of the leg portions 23, i.e., positions of flat surfaces of the chamfered portions 23b are arranged in a formation region D of the head body 21a of the mating fastener element 20 to be engaged therewith in the tape length direction.
In this way, because the curved shape of the leg portions 23 is formed, a unique curved shape of the fastener element 20 can be emphasized to be actualized and also an appropriate attaching strength of the fastener element 20 to the fastener tape 11 can be stably achieved. Further, if the leg portions 23 are prevented from being too strongly curved, it is also possible to inhibit flexibility of the slide fastener 1 from being reduced due to the curved shape of the leg portions 23.
Further, in a case where the leg portions 23 of the fastener element 20 have the curved shape as described above, when a lateral pulling force of pulling the right and left fastener tapes 11 in a direction of separating the right and left fastener tapes 11 from each other is exerted on the right and left fastener tapes 11 in which the right and left element rows 12 are engaged with each other, a rotational moment is acted on fastener elements 20 located in a portion on which the lateral pulling force is exerted. Accordingly, the right and left fastener elements 20 in portions of the element rows 12 are likely to be rotated in a direction, in which the fastener elements 20 are disengaged from each other, when the lateral pulling force is exerted thereon.
Therefore, in the present embodiment 1, in order to prevent the right and left fastener elements 20 from being disengaged from each other even if the lateral pulling force is exerted thereon as described above, an attaching pitch or size of the fastener element 20, a protruding height of the engaging protrusion portion 24 of the fastener element 20 and the like are adjusted. Thus, as shown in Fig. 5, where a size of a distance between head bodies 21a of adjacent fastener elements 20 in one fastener stringer 10 is a and a size of an insertion depth, in the tape length direction, of the engaging protrusion portion 24 of the fastener element 20 which is inserted in the engaging recess portion 25 of the mating fastener element 20 to be engaged therewith is b, a value of b/a is set to 0.25 or more.
In this way, because the value of b/a is set to 0.25 or more, an increased insertion depth of the engaging protrusion portion 24 of each fastener element 20 inserted in the engaging recess portion 25 of the mating fastener element 20 to be engaged therewith can be achieved. Accordingly, even when the fastener elements 20 are moved as if being rotated by the lateral pulling force exerted thereon, the right and left fastener elements 20 are not disengaged from each other. Also, because the engaging protrusion portion 24 of each fastener element 20 is abutted against an inner wall of the mating engaging recess portion 25 to be engaged therewith, it is possible to prevent a rotation angle of the fastener element 20 from being further increased.
Thus, the right and left element rows 12 can be stably kept engaged with each other without disengaging the right and left fastener elements 20 from each other, thereby enhancing a lateral pulling strength of the slide fastener 1.
Also, as described above, because the engaging protrusion portion 24 of the fastener element 20 is abutted against the inner wall of the mating engaging recess portion 25 to be engaged therewith and thus rotation of the fastener element 20 can be inhibited, the maximum rotation angle of the fastener element 20, which is rotated by the lateral pulling force exerted thereon, relative to a normal direction of the fastener element 20 is limited to 20o or less, preferably 15o or less.
Further, in the present embodiment 1, the value of b/a is set to 0.25 or more so that the engaging protrusion portion 24 can be inserted deeply into the mating engaging recess portion 25 to be engaged therewith, a thrust strength which means a strength of the engaged state of the element rows 12 against an external force exerted in the tape front-and-back direction can be also enhanced.
Also, in the present embodiment 1, the value of b/a is set to 0.30 or less, so that the engaging protrusion portion 24 of each fastener element 20 can be prevented from being inserted too deeply into the engaging recess portion 25 of the mating fastener element 20 to be engaged therewith. Accordingly, reduction in flexibility of the right and left fastener stringers 10 (fastener chain) engaged with each other can be inhibited and thus an appropriate flexibility thereof can be stably achieved.
Further, in the present embodiment 1, a ratio of an size b of an insertion depth, in the tape length direction, of the engaging protrusion portion 24, which is inserted in the engaging recess portion 25 of the mating fastener element 20 to be engaged therewith, to a size c of a protruding dimension, in the tape length direction, of the engaging protrusion portion 24, which protrudes from the front surface of the head body 21a (i.e., a value of b/c×100) is set to 65% or more and 85% or less, preferably 70% or more and 80% or less.
In this way, because the ratio of the insertion depth to the protruding dimension of the engaging protrusion portion 24 is set to 65% or more, the engaging protrusion portion 24 of the fastener element 20 in an engaged state of the right and left element rows 12 is inserted deeply into the engaging recess portion 25 of the mating fastener element 20 to be engaged therewith. Accordingly, an engaging strength of the slide fastener 1 can be enhanced and thus a desired lateral pulling strength or thrust strength can be stably achieved.
Further, because the ratio of the insertion depth to the protruding dimension of the engaging protrusion portion 24 is set to 85% or less, it is possible to prevent engagement of the right and left element rows 12 from becoming excessively strong. Accordingly, the right and left element rows engaged with each other can be prevented from being stiffened and thus an appropriate flexibility of the slide fastener 1 can be stably achieved. Also, an operation of engaging or disengaging the right and left element rows 12 with or from each other by sliding the slider 30 can be smoothly performed and thus a good slidability of the slider 30 can be stably achieved.
Meanwhile, according to the present embodiment 1, as described above, the front and rear surfaces of the head body 21a and the front and rear surfaces of the body portion 22 are respectively arranged on the same flat surfaces perpendicular to the tape length direction, and the front and rear surfaces of the leg portions 23 are formed as the curved surfaces curved in a direction oblique to the front and rear surfaces of the head body 21a and the body portion 22.
Accordingly, boundaries between the flat surfaces perpendicular to the tape length direction and the curved surfaces curved in a direction oblique to the flat surfaces are positioned at a boundary between the body portion 22 and the leg portions 23 (i.e., at a location of the inner peripheral surface on the crotch portion in the element length direction (tape width direction).
However, according to the present invention, the boundary positions between the flat surface and the curved surfaces are not limited to the location, and accordingly, the boundary positions between the flat surface and the curved surfaces may be set in a formation region of the body portion 22 in the element length direction (tape width direction) so long as the front and rear surfaces of the head body 21a are formed as flat surfaces perpendicular to the tape length direction and also the leg portions 23 extend to be curved in a direction oblique to the flat surfaces. Namely, curved surfaces curved in a direction oblique to the front and rear surfaces of the head body 21a may be formed to extend over the body portion 22 and the leg portions 23 of the fastener element 20.
Meanwhile, in the present invention, a case where the boundary positions between the flat surfaces and the curved surfaces are spaced away from the head body 21a is preferable in that a shape of the engaging head portion 21 can be stabilized and thus desired strengths can be easily achieved. Accordingly, the boundary positions between the flat surfaces and the curved surfaces are preferably set to the location of the boundary between the body portion 22 and the leg portions 23 as in the present embodiment 1.
Next, a method of manufacturing the fastener element 20 of the present embodiment 1 will be described with reference to Figs. 8 and 9.
First, a rectangular wire material 40 made of metal, such as copper, copper alloy or aluminum alloy is pressed using a pair of upper and lower molds 41a and 41b as shown in Fig. 8, so that the rectangular wire material 40 is partially plastically deformed and thus engaging protrusion portions 24 and engaging recess portions 25 are formed at a predetermined pitch.
Subsequently, the rectangular wire material 40 having the engaging protrusion portions 24 and the engaging recess portions 25 formed thereon is blanked to correspond to an outer peripheral shape of the fastener element 20 using a cutting punch 42 and a cutting die 43 as shown in Fig. 9.
The cutting die 43 has a though-hole 43a formed to have a cross-sectional shape corresponding to the outer peripheral shape of the fastener element 20. Also, the cutting punch 42 is provided, on a distal end portion thereof, with a head-side flat portion 42a having a flat surface to be abutted against portions of the rectangular wire material 40 corresponding to the head body 21a and the body portion 22, a receiving recess portion 42b provided to be recessed in the head-side flat portion 42a and thus to receive the engaging protrusion portion 24, a leg portion-forming portion 42c having a curved surface curved in a direction oblique to the flat surface of the head-side flat portion 42a, and a chamfered portion-forming portion 42d arranged at a position corresponding to the distal end portions of the leg portions 23 of the fastener element 20. In this case, the curved surface of the leg portion-forming portion 42c is convexly curved in an obliquely ascending direction, which is a direction opposite to a direction, relative to the flat surface of the head-side flat portion 42a. Also, the chamfered portion-forming portion 42d is configured to have a surface parallel to the flat surface of the head-side flat portion 42a.
Using the cutting punch 42 and the cutting die 43, blanking is performed on the rectangular wire material 40 having the engaging protrusion portions 24 and the engaging recess portions 25 formed thereon, in such a manner that the cutting punch 42 is collided with a surface of the rectangular wire material 40 to become the front surface of the fastener element 20. Therefore, the fastener element 20 having a predetermined outer peripheral shape is blanked and also the leg portions 23 of the blanked fastener element 20 can be plastically deformed in a curved shape obliquely curved in a protruding direction of the engaging protrusion portion 24 relative to the front and rear surfaces of the head body 21a.
Particularly, in this case, after blanking is initiated by bringing the head-side flat portion 42a in contact with the rectangular wire material 40, the leg portion-forming portion 42c is brought in contact with the rectangular wire material 40 so that the leg portions 23 are curved. Accordingly, the leg portions 23 of the fastener element 20 can be smoothly and stably deformed in a predetermined curved shape while the fastener element 20 is blanked by the cutting punch 42.
Further, because the distal end portion of the cutting punch 42 is provided with the chamfered portion-forming portion 43d, the chamfered portions 23b on the distal end portions of the leg portions 23 of the fastener element 20 can be stably formed by the chamfered portion-forming portion 42d upon blanking of the fastener element 20.
Particularly, in the present embodiment 1, the engaging protrusion portion 24 previously formed on the rectangular wire material 40 is received in the receiving recess portion 42b provided on the distal end portion of the cutting punch 42 upon blanking of the fastener element 20. Thus, a portion of the rectangular wire materiel 40, which is to be blanked, can be easily and stably positioned relative to the cutting punch 42 and the cutting die 43, and also the engaging protrusion portion 24 can be prevented from being deformed upon blanking of the fastener element 20, so that the shape of the engaging protrusion portion 24 can be stably maintained.
By performing blanking as described above, the fastener element 20 with the pair of leg portions 23 spread can be obtained and then a polishing process, a painting process and the like are performed on the obtained fastener element 20, thereby manufacturing the fastener element 20 of the present embodiment 1.
Also, the fastener element 20 of the present embodiment 1 manufactured in this way has a form in which the pair of leg portions 23 are spread from the base end portions, which are located toward the body portion 22, toward the distal end portions thereof in the element width direction. Accordingly, the tape side edge portion of the fastener tape 11 is inserted between the pair of leg portions 23, and then the pair of leg portions 23 are crimped in an inward direction of approaching each other so that the fastener element 20 is plastically deformed, thereby attaching (implanting) the fastener element 20 to the fastener tape 11.
Therefore, the fastener stringer 10 is manufactured. Also, two fastener stringers 10 manufactured in this way are combined as one set and then element rows 12 of the fastener stringers 10 are engaged with each other, thereby obtaining the fastener chain. Further, the slider 30 is attached on the element rows 12 of the fastener chain, and then the top stops 5 and the separable end stop 6 are fixed at predetermined locations on the fastener chain, thereby manufacturing the slide fastener 1 of the present embodiment 1 shown in Fig. 1.
In the slide fastener 1 of the present embodiment 1 obtained in this way, the leg portions 23 of each fastener element 20 have the curved shape curved in the protruding direction of the engaging protrusion portion 24 along the tape length direction relative to the front and rear surfaces of the head body 21a. Accordingly, the slide fastener 1 has an exterior appearance quality completely different from those of conventional slide fasteners having typical fastener elements and thus can be differentiated from other articles.
Further, because the leg portions 23 are formed in the curved shape and then are fixed on the fastener tape 11, the fastener element 20 is hardly inclined forward or rearward in the tape length direction. Accordingly, for example, even if thicknesses of the leg portions 20 are slightly thinned (i.e., dimensions (thickness dimensions) of the leg portions 23 in the tape length direction is reduced), a posture of the fastener element 20 on the fastener tape 11 can be stably maintained. Also, because the leg portions 23 are formed in the curved shape, a contact area between the leg portions 23 and the fastener tape 11 is increased. Thus, it is expected that an attaching strength of the fastener element 20 on the fastener tape 11 can be enhanced.
Also, in the slide fastener 1 of the present embodiment 1, even if the leg portions 23 are formed in the curved shape, the front and rear surfaces of the head body 21a are arranged to be parallel to each other in the tape width direction and also the engaging head portion 21 of each fastener element 20 is formed to be generally identical to engaging head portions of conventional typical fastener elements. Further, the value of b/a or the ratio of the insertion depth to the protruding dimension of the engaging protrusion portion 24 as described above is set within a predetermined range.
Accordingly, in the slide fastener 1 of the present embodiment 1, the right and left element rows 12 can be smoothly engaged with each other by sliding the slider 30, and also a good slidability of the slider 30 can be further stably achieved. Further, a lateral pulling strength and thrust strength equal to or higher than those of conventional slide fastener having typical fastener elements can be stably achieved.
Also, in the present embodiment, even if the leg portions 23 are formed in the curved shape, a curving direction of the leg portions 23 relative to the front and rear surfaces of the head body 21a is oriented to the front direction, which is the protruding direction of the engaging protrusion portion 24 from the head body 21a. Further, in the slide fastener 1 of the present embodiment 1, the engaging protrusion portion 24 of the fastener element 20 protrudes from the head body 21a in a direction along which the slider 30 is slid to close the slide fastener 1, and for example, when fastener elements 20 have been moved into the element guide passage of the slider 30 as shown in Fig. 6, the engaging protrusion portions 24 thereof are arranged to protrude toward the shoulder mouths of the slider 30, not the rear mouth.
Accordingly, when the slider 30 is slid along such a fastener-closing direction, fastener elements 20, which are moved into the element guide passage from the shoulder mouth side of the slider 30, are easy to be moved in the tape width direction at the vicinity of the shoulder mouths of the slider 30. However, in the present embodiment 1, the leg portions 23 of each fastener element 20 are covered in the front direction corresponding to the protruding direction of the engaging protrusion portion 24 from the head body 21a. Therefore, even if fastener elements 20 are moved at the vicinity of the shoulder mouths of the slider 30 and thus for example, come in contact with the right and left flange portions 36 of the slider 30, the leg portions 23 of the fastener elements 20 can hardly damage the flange portions 36.
On the other hand, fastener elements 20 located at the vicinity of the rear mouth of the slider 30 are engaged with each other and also positions thereof in the tape width direction are retained by the right and left flange portions 36 of the slider 30. Accordingly, the fastener elements 20 are hardly moved in the tape width direction at the vicinity of the rear mouth of the slider 30.
Therefore, even if the leg portions 23 of the fastener element 20 is curved in the front direction, for example, when the slider 30 is slid in a direction of opening the slide fastener 1 so that the right and left fastener elements 20 engaged with each other are moved into the element guide passage from the rear mouth of the sider 30, the leg portions 23 of the fastener elements 20 are hardly caught on and damage the right and left flange portions 36 of the slider 30.
Further, in the slide fastener 1 of the present embodiment 1, because the leg portions 23 of the fastener element 20 is curved in the front direction, for example, as shown in Fig. 7, a distance between leg portions 23 of fastener elements 20 arranged at the most rear ends of the element rows 12 and the separable pin 7 or retainer pin 8 arranged adjacent to the rear end potions of the element rows 12 can be gradually increased toward the distal end portions of the leg portions 23.
Accordingly, a partial flexibility of the fastener stringer 10 between the fastener elements 20 and the separable pin 7 or retainer pin 8 can be enhanced, and thus for example, a direction of the separable pin 7 or retainer pin 8 can be easily inclined in the tape width direction relative to the element rows 12.
In this way, because the direction of the separable pin 7 or retainer pin 8 can be easily inclined, an operation of inserting the separable pin 7 into the retainer box 9 through the element guide passage of the slider 30 or an operation of removing the separable pin 7 from the retainer box 9 through the element guide passage of the slider 30 can be more smoothly performed. Thus, operability of the separable end stop 6 can be enhanced.
Alternatively, although in the present embodiment 1, the separable end stop 6 is constituted of the separable pin 7, the retainer pin 8 and the retainer box 9 as described above, the present invention is not limited to that. For example, the present invention can be also similarly applied to a case where a separable end stop is provided on a so-called double open-type slide fastener in which right and left fastener stringers can be separated in both front and rear directions.
For example, the separable end stop for the double open-type slide fastener is configured so that two sliders are slidably attached on element rows of right and left fastener stringers with rear mouths thereof facing each other, a separable pin is fixed on a rear end portion of one fastener stringer and another separable pin is fixed on a rear end portion of the other fastener stringer. Thus, a retainer box equipped in a typical separable end stop is eliminated.
Also, when the fastener element 20 of the embodiment 1 as described above is manufactured, the engaging protrusion portion 24 and the engaging recess portion 25 are formed on the rectangular wire material 40, and then as shown in Fig. 7, blanking is performed by colliding the cutting punch 42 with a surface (first main surface) of the rectangular wire material 40 on which the engaging protrusion portion 24 is formed, thereby manufacturing the fastener element 20.
Alternatively, according to the present invention, the fastener element 20 may be manufactured by forming the engaging protrusion portion 24 and the engaging recess portion 25 on the rectangular wire material 40 and then as shown in Fig. 10, performing blanking using a cutting die 48 and a cutting punch 47 in such a manner that the cutting punch 47 is collided with a surface (second main surface) of the rectangular wire material 40 in which the engaging recess portion 25 is formed.
In this case, the cutting die 48 has a though-hole 48a formed to have a cross-sectional shape corresponding to the outer peripheral shape of the fastener element 20. Also, the cutting punch 47 is provided, on a distal end portion thereof, with a head-side flat portion 47a having a flat surface to be abutted against portions of the rectangular wire material 40 corresponding to the head body 21a and the body portion 22, an inserting protrusion portion 47b provided to protrude from the head-side flat portion 47a and thus to be inserted in the engaging recess portion 25 and a leg portion-forming portion 47c having a curved surface concavely curved in an obliquely descending direction relative to the flat surface of the head-side flat portion 47a.
Using the cutting punch 47 and the cutting die 48, blanking is performed on the rectangular wire material 40 having the engaging protrusion portions 24 and the engaging recess portions 25 formed thereon, in such a manner that the cutting punch 47 is collided with a surface of the rectangular wire material 40 to become the rear surface of the fastener element 20. Therefore, the fastener element 20 having a predetermined outer peripheral shape is blanked and also the leg portions 23 of the blanked fastener element 20 can be plastically deformed in a curved shape obliquely curved in the protruding direction of the engaging protrusion portion 24 relative to the front and rear surfaces of the head body 21a.
Also, in this case, the inserting protrusion portion 47b provided to protrude on the distal end portion of the cutting punch 47 in inserted in the engaging recess portion 25 previously formed on the rectangular wire material 40. Thus, a portion of the rectangular wire materiel 40, which is to be blanked, can be easily and stably positioned relative to the cutting punch 47 and the cutting die 48, and also the engaging recess portion 25 can be prevented from being deformed upon blanking of the fastener element 20, so that the shape of the engaging recess portion 25 can be stably maintained.
By performing blanking as described above, the fastener element 20 with the pair of leg portions 23 spread can be obtained. In this case, when the fastener element 20 is blanked, front surfaces of the distal end portions of the leg portions 23 of the fastener element 20 are likely to be cut out so that the chamfered portions 23b are formed. Also, on the obtained fastener element 20, a processing for forming the chamfered portions 23b on the distal end portions of the leg portions 23 is performed as necessary, and then a polishing process, a painting process and the like are performed, thereby manufacturing the single-side fastener element of the present invention.

Embodiment 2

Fig 11 is a front view of a fastener element according to the present embodiment 2, as viewed in a tape length direction, and Fig. 12 is a sectional view of the fastener element.
The present embodiment 2 is only different in shape of each fastener element from the foregoing embodiment 1, but the other configurations are the same as those of the slide fastener of the foregoing embodiment 1. Thus, the present embodiment 2 will be mainly described with respect to the fastener element.
The slide fastener of the present embodiment 2 includes a pair of right and left fastener stringers having element rows, in which a plurality of fastener elements 50 are provided in a row, respectively formed on tape side edge portions of right and left fastener tapes, a slider arranged to be slidable along the element rows, top stops arranged adjacent to front ends of the element rows and a separable end stop arranged adjacent to rear ends of the element rows.
The fastener element 50 of the present embodiment 2 is constructed of a metal, such as copper, copper alloy or aluminum alloy. As shown in Figs. 11 and 12, the fastener element 50 includes an engaging head portion 51 having engaging protrusion portions 54 and fitting space portions 55, a body portion 52 extending from one end of the engaging head portion 51, and a pair of leg portions 53 extending to be bifurcated from one end of the body portion 52.
Also, the fastener element 50 is configured as a double side element in which the engage protrusion 54 and the fitting space portion 55 are arranged as one set on each of a front surface (first main surface) and a rear surface (second main surface) of the engaging head portion 51, and also is symmetrically formed with respect to the center position thereof in an element width direction (tape front-and-back direction).
The engaging head portion 51 of the present embodiment 2 includes a head body 51a having a constant size in element thickness dimension (dimension in the tape length direction) between the front surface and the rear surface thereof, engaging protrusion portions 54 provided to protrude from front and rear surfaces of the head body 51a, and right and left extension portions 57 extending toward a tape outward side (a head distal end side) from a body portion 52 on the front and rear surfaces of the head body 51a.
The head body 51a of the engaging head portion 51 is arranged to have a predetermined thickness set so that an element thickness dimension thereof is smaller than that of the body portion 52 by interposing a step therebetween. Also, the front and rear surfaces of the head body 51a are formed as flat surfaces perpendicular to the tape length direction (flat surfaces parallel to the tape width direction), and a dimension of the head body 51 in the tape length direction has a constant size.
When viewing the engaging head portion 51 from the front side as shown in Fig. 1, a distal end edge of the head body 51a is arranged to be parallel to the element width direction, and side edges of the head body 51a are arranged to be curved relative to the element length direction so that a dimension of the head body 51a in the element width direction is gradually reduced toward the front end edge thereof.
The engaging protrusion portions 54 arranged on the front and rear surfaces of the head body 51a are provided to protrude in a mountain shape from the front and rear surfaces of the head body 51a in the middle portion thereof in the element width direction and are formed at a predetermined distance from the body portion 52.
The right and left extension portions 57 are arranged at locations spaced from each other to have a predetermined element thickness dimension raised from the head body 51a and also to extend from the body portion 52 toward right and left sides of the engaging protrusion portions 54. In this case, predetermined gaps are provided between the engaging protrusion portions 54 and the right and left extension portions 57. Also, front and rear surfaces of right and left extension portions 57 are arranged on the same planes as those of front and rear surfaces of the body portion 52.
In the engaging head portion 51 of the present embodiment 2, the fitting space portions 55 surrounded by the engaging protrusion portions 54, right and left extension portions 57 and body portion 52 are respectively formed in the front and rear surfaces of the head body 51a. Each fitting space portion 55 has a bottom surface 55a set at the same height location in the element thickness direction (tape length direction) as those of the front and rear surfaces of the head body 51a.
The body portion 52 of the present embodiment 2 is formed to be raised from the bottom surfaces 55a of the fitting space portions 55 in the element thickness direction and thus to have an element thickness dimension larger than that of the head body 51a of the engaging head portion 51. The body portion 52 is arranged to extend in the element length direction (tape width direction) from positions of end edges of the bottom surfaces 55a of the fitting space portions 55 to a position of a tape sandwiching surface 56 on a crotch portion from which the pair of leg portions 53 are branched.
Namely, in the present embodiment 2, the body portion 52 refers to a portion arranged to extend in the element length direction from the positions of the end edges of the bottom surfaces 55a of the fitting space portions 55 to the position of the tape sandwiching surface 56 on the crotch portion, and thus a portion located more toward the tape outward side than the body portion 52 is referred to as the engaging head portion 51 and a portion located more toward the tape inward side than the body portion 52 is referred to as leg portions 53.
The leg portions 53 of the present embodiment 2 extend from the body portion 52 toward the tape inward side, and hook-shaped bent portions 53a bent in a direction (inward direction) of approaching each other are respectively arranged on distal regions of the pair of leg portions 53 (end regions thereof on the tape inward side). Also, an inner peripheral surface defined by the body portion 52 and the pair of leg portions 53 is arranged to be parallel to the tape length direction, and the inner peripheral surface becomes the tape sandwiching surface 56 coming in close contact with the fastener tape.
Also, in the fastener element 50 of the present embodiment 2, the pair of leg portions 53 extend to be curved in a direction oblique to the front and rear surfaces of the head body 5 1 a (or relative to the tape width direction), so that distal end portions of the leg portions 53 are located more forward than base end portions thereof (end portions located toward the body portion 52).
In this case, front surfaces of portions of the leg portions 53, except the distal end portions, are formed as curved surfaces concavely curved to be located more forward as going toward distal ends (tape inward sides) of the leg portions 53. Also, rear surfaces of the leg portions 53 are formed as curved surfaces convexly curved to be located more forward as going toward distal ends (tape inward sides) of the leg portions 53. Further, thickness dimensions (dimensions in the tape length directions) of the portions of the leg portions 53, except the distal end portions, have generally substantially constant sizes.
Alternatively, in the present invention the pair of leg portions 53 may extend to be linearly inclined in a direction oblique to the tape width direction so that the distal end portions of the leg portions 53 are located more forward than the base end portions.
Also, the front surfaces of the distal end portions of the leg portions 53 of the present embodiment 2 are respectively provided with chamfered portions 53b for the purpose of providing a good hand feeling or skin feeling to the fastener element 50 or causing the fastener element 50 to be hardly caught on the slider upon sliding of the slider. The chamfered portions 53b are constructed by surfaces parallel to the front and rear surfaces of the head body 51a.
In this case, the curved shape of the leg portions 53 is formed so that positions of front surfaces of the distal end portions of the leg portions 23, i.e., positions of flat surfaces of the chamfered portions 53b are arranged in a formation region of the head body 51a of the mating fastener element 50 to be engaged therewith in the tape length direction.
Further, in the present embodiment 2, a ratio of a size of an insertion depth, in the tape length direction, of the engaging protrusion portion 54, which is inserted in the respective engaging recess portion 55 of the mating fastener element 50 to be engaged therewith, to a size of a protruding dimension, in the tape length direction, of the engaging protrusion portion 54, which protrudes from the front surface of the head body 51a is set to 65% or more and 85% or less.
Because the ratio of the insertion depth to the protruding dimension of the engaging protrusion portion 54 is set to 65% or more, an engaging strength of the slide fastener 1 can be enhanced and thus a desired lateral pulling strength or thrust strength can be stably achieved. Also, because the ratio is set to 85% or less, it is possible to prevent engagement of the right and left element rows 12 from becoming excessively strong. Accordingly, an appropriate flexibility of the slide fastener or a good slidability of the slider can be stably achieved.
Further, in the present embodiment 2, boundaries between the front and rear flat surfaces of the body portion 52 arranged to be perpendicular to the tape length direction and the curved surfaces of the leg portions 53 curved in a direction oblique to the flat surfaces are positioned at a location of a boundary between the body portion 52 and the leg portions 53. Alternatively, in the present invention, the boundary positions between the flat surface of the body portion 52 and the curved surfaces curved relative to the flat surfaces may be set in a formation region of the body portion 52 in the element length direction (tape width direction).
When the fastener element 50 of the present embodiment 2 as described above is manufactured, a rectangular wire material made of metal, such as copper, copper alloy or aluminum alloy is first pressed using a pair of upper and lower molds so that the rectangular wire material is partially plastically deformed and thus engaging protrusion portions 54 and fitting space portions 55 are formed at a predetermined pitch on both surfaces of the rectangular wire material.
Subsequently, the rectangular wire material 40 having the engaging protrusion portions 54 and the fitting space portions 55 formed thereon is blanked to correspond to an outer peripheral shape of the fastener element 50 using a cutting punch and a cutting die.
In this case, the cutting die has a though-hole formed to have a cross-sectional shape corresponding to the outer peripheral shape of the fastener element 50. Also, a distal end portion of the cutting punch is provided at least with a head-side flat portion having a flat surface to be abutted against a portion of the rectangular wire material corresponding to the head body 51a, a receiving recess portion provided to be recessed in the head-side flat portion and thus to receive the engaging protrusion portion 54, and a leg portion-forming portion 42c having a curved surface curved in a direction oblique to the flat surface of the head-side flat portion.
By performing blanking with the cutting punch and the cutting die, the fastener element 50 having a predetermined outer peripheral shape is blanked and also the leg portions 53 of the blanked fastener element 50 can be plastically deformed in a curved shape obliquely curved relative to the front and rear surfaces of the head body 51a and the body portion 52. Then, a polishing process, a painting process and the like are performed on the obtained fastener element 50, thereby manufacturing the fastener element 50 of the present embodiment 2.
The fastener element 50 of the present embodiment 2 manufactured in this way has a form in which the pair of leg portions 53 are spread. Accordingly, the tape side edge portion of the fastener tape is inserted between the pair of leg portions 53, and then the pair of leg portions 53 are crimped in an inward direction of approaching each other, thereby manufacturing a fastener stringer with fastener elements 50 attached on the fastener tape. Also, two fastener stringers manufactured in this way are combined as one set and then fastener rows of the fastener stringers are engaged with each other, thereby obtaining the fastener chain.
The slide fastener of the present embodiment 2 constructed using the fastener chain obtained in this way has an exterior appearance quality completely different from those of conventional slide fasteners having typical fastener elements. Also, because the leg portions 53 are formed in the curved shape and then are fixed on the fastener tape, a posture of the fastener element 50 on the fastener tape can be stably maintained.
Further, in the slide fastener of the present embodiment 2, even if the leg portions 53 are formed in the curved shape, the front and rear surfaces of the head body 51a are arranged to be parallel to each other in the tape width direction and also the engaging head portion 51 of each fastener element 50 is formed to be generally identical to engaging head portions of conventional typical fastener elements.
Accordingly, in the slide fastener of the present embodiment 2, the right and left element rows can be smoothly engaged with each other by sliding the slider, and also a good slidability of the slider can be stably achieved. Further, a lateral pulling strength and thrust strength equal to or higher than those of conventional slide fastener having typical fastener elements can be stably achieved.

Description of Reference Numerals

1: Slide Fastener
5: Top Stop
6: Separable End Stop
7: Separable Pin
8: Retainer Pin
9: Retainer Box
10: Fastener Stringer
11: Fastener Tape
12: Element Row
20: Fastener Element
21: Engaging Head Portion
21a: Head Body
22: Body Portion
23: Leg Portion
23a: Bent Portion
23b: Chamfered Portion
24: Engaging Protrusion Portion
25: Engaging Recess Portion
26: Tape Sandwiching Surface
30: Slider
31: Slider Body
32: Pull Tab
33: Upper Blade
34: Lower Blade
35: Guide Post
36: Flange Portion
37: Pull Tab Attaching Portion
40: Rectangular Wire Material
41a, 41b: Mold
42: Cutting Punch
42a: Head-Side Flat Portion
42b: Receiving Recess Portion
42c: Leg Portion-Forming Portion
42d: Chamfered Portion-Forming Portion
43: Cutting Die
43a: Through-Hole
47: Cutting Punch
47a: Head-Side Flat Portion
47b: Inserting Protrusion Portion
47c: Led Portion-Forming Portion
48: Cutting Die
48a: Through-Hole
50: Fastener Element
51: Engaging Head Portion
51a: Head Body
52: Body Portion
53: Leg Portion
53a: Bent Portion
53b: Chamfered Portion
54: Engaging Protrusion Portion
55: Fitting Space Portion
55a: Bottom Surface
56: Tape Sandwiching Surface
57: Extension Portion
a: Size of Distance between Head Bodies of Adjacent Fastener Elements
b: Size of Insertion Depth of Engaging Protrusion Portion
c: Size of Protruding Dimension of Engaging Protrusion Portion
D: Formation Region of Head Body

Claims

A fastener chain, comprising a pair of right and left fastener tapes (11) and a pair of fastener stringers (10) having a plurality of metal fastener elements (20) crimped and attached on opposing tape side edge portions of the fastener tapes (11) along a tape length direction, wherein each fastener element (20) comprises an engaging head portion (21), a body portion (22) arranged on one end side of the engaging head portion (21) and a pair of leg portions (23) extending to be bifurcated from one end of the body portion (22), wherein the engaging head portion (21) comprises a head body (21a) having a first main surface and a second main surface opposite to the first main surface, an engaging protrusion portion (24) provided to protrude from the first main surface of the head body (21a) and an engaging recess portion (25) provided to be recessed in the second main surface of the head body (21a),
wherein the first and second main surfaces of the head body (21a) are flat surfaces perpendicular to the tape length direction;
characterized in that the pair of leg portions (23) extend to be curved in a direction oblique to the first and second main surfaces of the head body (21a).
The fastener chain according to claim 1, wherein the pair of leg portions (23) are formed to be curved relative to the first and second main surfaces of the head body (21a) in a protruding direction of the engaging protrusion portion (24).
A fastener chain, comprising a pair of right and left fastener tapes and a pair of fastener stringers having a plurality of metal fastener elements (50) crimped and attached on opposing tape side edge portions of the fastener tapes along a tape length direction, wherein each fastener element (50) comprises an engaging head portion (51), a body portion (52) arranged on one end side of the engaging head portion (51) and a pair of leg portions (53) extending to be bifurcated from one end of the body portion (52), wherein the engaging head portion (51) comprises a head body (51a) having a first main surface and a second main surface opposite to the first main surface, engaging protrusion portions (54) provided to protrude from the first and second main surfaces of the head body (51a) and fitting space portions (55) arranged between the engaging protrusion portions (54) and the body portion (22) on the first and second main surfaces and configured to allow the mating engaging protrusion portion (54) to be fitted therein,
wherein the first and second main surfaces of the head body (51a) are flat surfaces perpendicular to the tape length direction
characterized in that the pair of leg portions (23) extend to be curved in a direction oblique to the first and second main surfaces of the head body (51a).
The fastener chain according to any one of claims 1 to 3, wherein first main surfaces of distal end portions of the leg portions (23, 53), which are surfaces facing the same side as that in the first main surface of the engaging head portion (21, 51), are arranged in a formation region (D) of the head body (21a, 51a) of the engaging head portion (21, 51) of the mating fastener element (20, 50) in the tape length direction.
The fastener chain according to any one of claims 1 to 4, wherein a ratio of an insertion depth, in the tape length direction, of the engaging protrusion portion (24, 54), which is inserted in the engaging recess portion (25) or fitting space portion (55) of the mating fastener element (20, 50), to a protruding dimension, in the tape length direction, of the engaging protrusion portion (24, 54), which protrudes from the front main surface of the head body (21a, 51a), is set to 65% or more and 85% or less.
The fastener chain according to any one of claims 1 to 5, wherein, where a size of a distance between head bodies (21a, 51a) of adjacent fastener elements (20, 50) in one fastener stringer (10) is a and a size of an insertion depth, in the tape length direction, of the engaging protrusion portion (24, 54) which is inserted in the engaging recess portion (25) or fitting space portion (55) of the mating fastener element (20, 50) is b, a value of b/a is set to 0.25 or more and 0.30 or less.
The fastener chain according to any one of claims 1 to 6, wherein first main surfaces of the leg portions (23, 53) have, on distal end portions of the leg portions (23, 53), chamfered surfaces parallel to the first and second surfaces of the head body (21a, 51a).
A slide fastener constructed by attaching a slider (30) on the element rows (12) formed by the plurality of fastener elements (20, 50) of the fastener chain according to any one claims 1 to 7,
wherein the pair of leg portions (23, 53) are formed to be curved relative to the first and second main surfaces of the head body (21a, 51a) in a direction along which the slider (30) is slid to engage the pair of fastener stringers (10) with each other.
The slide fastener according to claim 8, further comprising a separable end stop (6) having a separable pin (7) fixed on a rear end portion of one fastener stringer (10) and a retainer pin (8) fixed on a rear end portion of the other fastener stringer (10),
wherein a distance between leg portions (23, 53) of fastener elements (20, 50) arranged at the most rear ends of the element rows (12) and the separable pin (7) or retainer pin (8) is gradually increased toward the distal end portions of the leg portions (23, 53).
A method of manufacturing a metal fastener element (20) comprising an engaging head portion (21), a body portion (22) arranged on one end side of the engaging head portion (21) and a pair of engaging protrusion portions (24) extending to be bifurcated from one end of the body portion (22), wherein the engaging head portion (21) comprises a head body (21a) having a first main surface and a second main surface opposite to the first main surface, an engaging protrusion portion (24) provided to protrude from the first main surface of the head body (21a) and an engaging recess portion (25) provided to be recessed in a bottomed shape in the second main surface of the head body (21a), the method comprising:
forming the engaging protrusion portion (24) and the engaging recess portion (24) on a metal rectangular wire material (40) by pressing;

blanking a portion of the rectangular wire material (40) having the engaging protrusion portion (24) and the engaging recess portion (25) formed thereon using a cutting die (43, 48) and a cutting punch (42, 47) to form the fastener element (20), wherein the cutting punch (42, 47) has, on a distal end thereof, a head-side flat portion (42a, 47a) having a flat surface to be abutted against the head body (21a) and a leg portion-forming portion (42c, 47c) curved in a direction oblique to the flat surface of the head-side flat portion (42a, 47a); and

curving the pair of leg portions (23) in a direction oblique to the first and second main surfaces of the head body (21a) upon blanking of the fastener element (20).
The method according to claim 10, wherein the cutting punch (42, 47) further comprises a receiving recess portion (42b) provided to be recessed in the head-side flat portion (42a) and thus to receive the engaging protrusion portion (24) or an inserting protrusion portion (47b) provided to protrude from the head-side flat portion (47a) and thus to be inserted in the engaging recess portion (25).
The method according to claim 10 or 11, wherein upon blacking of the fastener element (20), after blanking is initiated by bringing the head-side flat portion (42a) in contact with the rectangular wire material (40), the leg portion-forming portion (42c) is brought in contact with the rectangular wire material (40) so that the pair of leg portions (23) are curved.
The method according to any one of claims 10 to 12, further comprising:
providing a surface, which is curved relative to the flat surface of the head-side flat portion (42a) in a direction opposite to a blanking direction, on the leg portion-forming portion (42c); and

providing a chamfered portion-forming portion (42d), which has a surface parallel to the flat surface of the head-side flat portion (42a), at a location on the cutting die (43) corresponding to the distal end portions of the leg portions (23) of the fastener element (20).