Fastener element and fastener stringer

Abstract

A metal fastener element (10) according to the present invention has an engaging head (20) provided with a protrusion (22) and a recess (23), the ratio of the total width (Wo) to the total length (Lo) of the fastener element (10) is 40‒50%, and the ratio of the total width (Wo) to the total thickness (Do) of the fastener element (10) is 130‒145%. According to this fastener element (10), the manufacturing cost of a slide fastener (1) can be reduced. In addition, the weight of the slide fastener (1) can be reduced.

Description

Zipper elements and zipper stringers

[0001] The present invention relates to a metal fastener element and a fastener stringer having a plurality of metal fastener elements.

[0002] Copper-zinc alloys have excellent workability and have been widely used in various fields. Generally, zinc bullion is cheaper than copper bullion, so increasing the zinc content in the alloy can reduce material costs.

[0003] For example, International Publication No. 2012 / 004841 (Patent Document 1) discloses a metal fastener element made of a copper-zinc alloy having a two-phase structure of α and β phases. The fastener element of Patent Document 1 is formed from a copper-zinc alloy containing more than 35 mass% zinc and having a two-phase structure of α and β phases. In the copper-zinc alloy, the ratio of β phase is controlled to more than 10% and less than 40%. The α and β phase crystal grains are flattened and arranged in layers along the outer surface of the fastener element.

[0004] In the fastener element of Patent Document 1, the fastener element contains a large amount of zinc, which reduces material costs. Also, the flat, hard β-phase crystal grains arranged along the outer surface of the fastener element can effectively suppress the propagation of cracks from the outer surface of the fastener element. Therefore, it is possible to prevent the occurrence of season cracking and stress corrosion cracking in the fastener element.

[0005] International Publication No. 2012 / 004841

[0006] The fastener element of Patent Document 1 is formed of a copper-zinc alloy containing more than 35 mass% of zinc, which enables reduction in the manufacturing cost and weight of the slide fastener. However, there is a limit to the reduction in manufacturing cost and weight by simply changing the composition of the metal material of the fastener element as in Patent Document 1.

[0007] On the other hand, in a slide fastener having a plurality of metal fastener elements, an increase or decrease in the weight of the fastener elements significantly affects the transportation of the metal material forming the fastener elements and the transportation of a slide fastener product having a plurality of fastener elements. For this reason, there is a demand for a reduction in the weight of the fastener elements. In addition, in order to reduce the burden on the environment, there is a demand for a further reduction in the metal material used in the fastener elements.

[0008] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a fastener element that can reduce the manufacturing cost and weight of a slide fastener, apart from changing the composition of the metal material, and a fastener stringer having the fastener element.

[0009] In order to achieve the above object, the fastener element of the present invention is a metal fastener element attached to the fastener tape of a slide fastener, the fastener element having an engaging head with a convex portion and a concave portion, and when the dimensions of the entire fastener element in the element length direction and the element width direction are defined as the total length and total width of the fastener element, respectively, the ratio of the total width to the total length of the fastener element is 40% or more and 50% or less, and when the dimension of the fastener element in the element thickness direction at a part of the fastener element excluding the engaging head is defined as the total thickness, the ratio of the total width to the total thickness of the fastener element is 130% or more and 145% or less.

[0010] In the present invention, the fastener element has a body portion extending in the element length direction from the engaging head, a pair of legs branching off and extending from the body portion, and a pair of claw portions extending inward in the element width direction from the tip end of each of the legs, and the inner surface of each of the claw portions is inclined relative to the inner surface of the leg via a bend portion, and it is preferable that the dimension of each of the legs in the element width direction gradually decreases from the connecting portion connecting the leg to the body portion to the position of the bend portion.

[0011] In this case, when the dimension in the element width direction at the connecting portion of each of the legs is defined as a first width dimension and the dimension in the element width direction at the position of the bent portion of each of the legs is defined as a second width dimension, it is preferable that the ratio of the first width dimension to the total width of the fastener element is 35% or more and 45% or less, the ratio of the second width dimension to the total width of the fastener element is 10% or more and 35% or less, and the ratio of the second width dimension to the first width dimension is 55% or more and 70% or less.

[0012] Furthermore, when the difference between the total width of the fastener element and twice the size of the first width dimension is defined as the inner thigh width dimension, it is preferable that the ratio of the inner thigh width dimension to the total width of the fastener element is 0% or more and 46% or less.

[0013] In the fastener element of the present invention, when the dimension in the element length direction from the position of the connecting portion of the leg portion to the position of the bent portion is defined as a first length dimension, and the maximum value of the dimension in the element length direction from the position of the bent portion to the outer end surface of the claw portion facing the element length direction is defined as a second length dimension, it is preferable that the ratio of the first length dimension to the total length of the fastener element is 25% or more and 35% or less, the ratio of the second length dimension to the total length of the fastener element is 10% or more and 25% or less, and the ratio of the second length dimension to the first length dimension is 55% or more and 80% or less.

[0014] The interlocking head has a first surface facing the element thickness direction of the interlocking head and on which the recess is provided, and the recess has an opening that opens into the first surface. When the dimension of the opening in the element length direction at the center of the element width direction is defined as a central opening length and the dimension of the opening in the element width direction at the center of the element length direction is defined as a central opening width, the ratio of the central opening width to the central opening length is 100% or more and 130% or less. When the convex portion of the interlocking head is cut at the position of a second surface of the leg facing the element thickness direction, the dimension of the convex portion in the element length direction at the cut surface is defined as a head cutting length and the dimension of the convex portion in the element width direction at the cut surface is defined as a head cutting width, it is preferable that the ratio of the head cutting width to the head cutting length is 95% or more and 115% or less.

[0015] The recess of the coupling head has a recessed-side vertical inner peripheral surface having a portion inclined along the element length direction from the bottom surface of the recess toward the tip portion of the coupling head, and a recessed-side horizontal inner peripheral surface having a portion inclined along the element width direction from the bottom surface of the recess toward the side edge portion of the coupling head, the recessed-side vertical inner peripheral surface being inclined at an inclination angle of 70° or more and 85° or less with respect to the element length direction, and the recessed-side horizontal inner peripheral surface being inclined at an inclination angle of 65° or more and 85° or less with respect to the element width direction, The convex portion of the coupling head has a convex-side vertically inclined surface that is inclined from the top end surface of the convex portion toward the tip end of the coupling head in the element length direction, and a convex-side horizontally inclined surface that is inclined from the top end surface of the convex portion toward the side edge of the coupling head in the element width direction, the convex-side vertically inclined surface being inclined at an angle of 50° to 65° with respect to the element length direction, and the convex-side horizontally inclined surface being inclined at an angle of 60° to 75° with respect to the element width direction. In this case, the concave-side horizontal inner surface preferably has a first horizontal inner surface adjacent to the end surface of the side edge of the coupling head, and a second horizontal inner surface formed between the first horizontal inner surface and the bottom surface of the recess, the first horizontal inner surface being formed at a larger angle with respect to the element width direction than the second horizontal inner surface.

[0016] According to the present invention, there is provided a fastener stringer having the above-described plurality of fastener elements and the fastener tape to which the fastener elements are attached. In the fastener stringer of the present invention, when the average value of the overall width of the fastener elements is 1.3 mm or more and 1.5 mm or less, it is preferable that the attachment strength of each fastener element to the fastener tape is 60 N or more.

[0017] Next, the fastener stringer of the present invention is a fastener stringer having a plurality of metal fastener elements and a fastener tape to which the fastener elements are attached, in which, when the average value of the dimension in the element length direction of the entire fastener elements is 2.8 mm or more and 3.0 mm or less, the total weight of the plurality of fastener elements attached per 10 m of the fastener stringer in the tape length direction of the fastener tape is 93 g or less.

[0018] In the fastener stringer of the present invention, it is preferable that the metal is a copper-zinc alloy, the copper content in the copper-zinc alloy is 59 mass% or more and 71.5 mass% or less, and the zinc content in the copper-zinc alloy is 28.5 mass% or more and 41 mass% or less.

[0019] According to the fastener element and fastener stringer of the present invention, the manufacturing cost of the slide fastener can be reduced, and the weight of the slide fastener can also be reduced.

[0020] 2. It is a front view showing typically a slide fastener having a fastener element according to an embodiment of the present invention. It is an enlarged view showing typically an enlarged view of a main part of the slide fastener shown in FIG. 1. It is a front view of the fastener element when viewed from the front side of the slide fastener. It is a rear view of the fastener element when viewed from the rear side of the slide fastener. It is a plan view of the fastener element when viewed from above the slide fastener. It is a side view of the fastener element when viewed from the inside in the left-right direction of the slide fastener. It is an explanatory view showing a cross section of the fastener element taken along line VII-VII in FIG. 2 and also explaining typically the rotation of the fastener element. It is an explanatory view showing typically a method of measuring the attachment strength (pull-out strength) of the fastener element to the fastener tape.

[0021] In a slide fastener, the overall size of the fastener elements is generally changed depending on the application of the slide fastener, etc. On the other hand, when attempting to reduce the manufacturing cost and weight of a slide fastener by means other than changing the metal material forming the fastener elements, one possible means is, for example, to form each fastener element small.

[0022] However, when a slide fastener is formed by reducing the size of the fastener elements, although it is possible to reduce the weight of the fastener elements, this affects the application of the slide fastener, and also changes the attachment strength of the fastener elements to the fastener tape, the interlocking strength of the left and right fastener elements, and the sliding resistance and operability of the slider when the slide fastener is formed.

[0023] For example, in a conventional metal fastener element, when the fastener element is formed so that the dimension in the element length direction (total element length) of the fastener element is a certain size (for example, a size of 2.8 mm or more and 3.0 mm or less), in order to attach the fastener element to the fastener tape with appropriate attachment strength, the overall width and overall thickness of the fastener element also had to be at least a certain size. For this reason, in order to ensure appropriate attachment strength for each fastener element, it was extremely difficult to make at least one of the overall width and overall thickness smaller than the overall length of the fastener element.

[0024] In response to the above-mentioned problems, the inventors conducted various experiments and studies, and as a result, discovered a fastener element structure that allows the fastener element to have appropriate attachment strength to the fastener tape even when the overall width of the fastener element is reduced, and further, by clarifying the conditions under which appropriate attachment strength can be ensured, the present invention was completed.

[0025] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Fig. 1 is a front view schematically showing a slide fastener having a fastener element according to this embodiment. Fig. 2 is an enlarged view schematically showing a main part of the slide fastener. Figs. 3 to 6 are a front view, a rear view, a plan view, and a side view of the fastener element, respectively.

[0026] In the following description of the slide fastener, the front-rear direction refers to the direction along the tape length of the fastener tape, and is the direction along the sliding direction of the slider (see Figure 2). In this case, the direction in which the slider slides when closing the slide fastener is referred to as the front, and the direction in which the slider slides when opening the slide fastener is referred to as the rear.

[0027] The left-right direction refers to the tape width direction of the fastener tape, and is a direction parallel to the tape surface of the fastener tape and perpendicular to the tape length direction (see Figure 2). The inner side of the left-right direction is a direction that brings the left and right fastener stringers closer to each other. The outer side of the left-right direction is a direction that moves the left and right fastener stringers away from each other.

[0028] The vertical direction refers to the direction perpendicular to the tape surface of the fastener tape, and is the direction perpendicular to the tape length direction and tape width direction. In this case, the direction exposed to the outside when the slide fastener is used, or the direction in which the slider pull tab is arranged relative to the fastener tape, is referred to as the up direction. The direction opposite to the up direction is referred to as the down direction.

[0029] In describing fastener elements, the front-to-back direction (tape length direction), left-to-right direction (tape width direction), and up-to-down direction (tape front-to-back direction) of the slide fastener are sometimes referred to as the element thickness direction, element length direction, and element width direction of the fastener element, respectively (see Figures 3 to 6).

[0030] As shown in Figure 1, the slide fastener 1 of this embodiment has a pair of left and right fastener stringers 2 each having an element row 4 formed on opposing tape side edges of a fastener tape 3, a first fastening member 5 and a second fastening member 6 attached to the front end and rear end of the left and right fastener stringers 2, and a slider 7 slidably attached to the left and right element rows 4.

[0031] The element row 4 of each fastener stringer 2 is formed by attaching a plurality of metal fastener elements 10 to the fastener tape 3. The first stop member 5 and the second stop member 6 are also called an upper stop member and a lower stop member.

[0032] The slide fastener 1 of this embodiment is primarily characterized by the fastener stringer 2, and particularly the fastener elements 10. For example, the first fastening member 5 and the second fastening member 6 of this embodiment are formed substantially in the same manner as the first fastening member and the second fastening member used in a conventional slide fastener having a metal fastener element. Therefore, detailed description of the first fastening member 5 and the second fastening member 6 will be omitted.

[0033] The slider 7 of this embodiment has a slider body and a pull tab attached to the slider body. Note that in the present invention, the slider 7 is not particularly limited as long as it is formed so that the left and right element rows 4 can be engaged with and disengaged from each other by sliding the slider 7 along the element rows 4.

[0034] Each of the left and right fastener stringers 2 has a long, narrow fastener tape 3 formed in a strip shape and a plurality of metal fastener elements 10 attached to opposing tape side edges (tape inner side edges) of the fastener tape 3.

[0035] Each of the left and right fastener tapes 3 has a tape main body portion to be sewn to a fastener-retaining product such as clothing, and a tape side edge portion (sometimes referred to as an element attachment portion) that extends widthwise inward from one side edge of the tape main body portion and to which the fastener elements 10 are attached. The fastener tape 3 has a tape body 3a having a tape upper surface (first surface) and a tape lower surface (second surface), and a core cord portion 3b provided along the front-to-rear tape inner edge of the tape body 3a. The core cord portion 3b has a shape that bulges out in the vertical direction from the tape upper surface and tape lower surface of the tape body 3a.

[0036] Each fastener element 10 is formed of a copper-zinc alloy containing copper and zinc. The copper-zinc alloy of the fastener element 10 is a binary alloy containing copper and zinc as main components. The copper content in the copper-zinc alloy is preferably 59% by mass or more and 71.5% by mass or less. The zinc content is preferably 28.5% by mass or more and 41% by mass or less.

[0037] By setting the copper content in the copper-zinc alloy to 59% by mass or more and the zinc content to 41% by mass or less, the ductility and corrosion resistance of the copper-zinc alloy can be improved. By setting the copper content to 71.5% by mass or less and the zinc content to 28.5% by mass or more, it is possible to reduce material costs and the weight of the fastener element 10. For example, the fastener element 10 of this embodiment is formed from a copper-zinc alloy with a copper content of 65% by mass and a zinc content of 35% by mass.

[0038] The copper-zinc alloy of this embodiment is preferably, for example, a copper-zinc alloy (brass) specified in JIS as C2600, C2680, C2700, C2720, or C2800, or a copper-zinc alloy specified in ASTM as C26000, C26800, C27000, C27200, or C28000.

[0039] The copper-zinc alloy forming the fastener element may contain elements such as tin (Sn), manganese (Mn), aluminum (Al), silicon (Si), and unavoidable impurities, as long as the copper content or the copper and zinc contents are set within the ranges specified in JIS or ASTM.

[0040] By including a trace amount of at least one of Sn (e.g., 1.5 mass% or less), Mn (e.g., 3.0 mass% or less), Al (e.g., 2.0 mass% or less), and Si (e.g., 1.5 mass% or less) in the copper-zinc alloy, it is possible to obtain effects such as improving the strength and / or hardness of the copper-zinc alloy. Note that even if the above-mentioned elements and unavoidable impurities are included in the copper-zinc alloy, the respective contents and the total content are so small that they do not substantially affect the weight of the copper-zinc alloy.

[0041] Each fastener element 10 attached to the fastener tape 3 has a shape that is long in the element length direction (left and right direction of the slide fastener 1) and is substantially symmetrical in the element width direction (up and down direction of the slide fastener 1) as shown in Figures 3 and 4 when viewed from the element thickness direction (front and back direction of the slide fastener 1).

[0042] The fastener element 10 has an interlocking head 20 having an interlocking protrusion 22 and an interlocking recess 23, a body 30 extending from the interlocking head 20 toward one side of the element length direction (outside in the left-right direction), a pair of legs 40 branching off from the body 30 and extending toward one side of the element length direction, and a pair of claws 50 extending from the tip of each of the left and right legs 40 toward the inside in the element width direction.

[0043] As will be described later, the fastener element 10 of this embodiment is manufactured by carrying out a process including forming a wire rod called a Y-bar having an approximately Y-shaped cross section, slicing the wire rod (Y-bar) to a predetermined thickness to form an element material, and performing press processing or the like on the element material from the element thickness direction to form the interlocking head 20.

[0044] Here, for the fastener element 10 of this embodiment, the dimension in the element length direction of the entire fastener element 10 is defined as the overall length Lo of the fastener element 10. The dimension in the element width direction of the entire fastener element 10 is defined as the overall width Wo of the fastener element 10 (see FIG. 3). The dimension in the element thickness direction (front-rear direction) of the fastener element 10 in a portion excluding the coupling head 20 is defined as the overall thickness Do of the fastener element 10 (see FIG. 5).

[0045] When compared with conventional metal fastener elements such as those described in Patent Document 1, the fastener element 10 of this embodiment is formed such that, if the overall length Lo and overall thickness Do of the fastener element 10 are the same as those of conventional fastener elements, the overall width Wo of the fastener element 10 is smaller than that of conventional fastener elements.

[0046] Specifically, in the case of conventional metal fastener elements, in the shape of the fastener element when attached to the fastener tape, the ratio of the total width Wo to the total length Lo of the fastener element is usually 65% ​​or more, and the ratio of the total width Wo to the total thickness Do is 190% or more.

[0047] In contrast, the fastener element 10 of this embodiment is formed so that, when attached to the fastener tape 3, as shown in Figures 3 to 6, the ratio of the total width Wo to the total length Lo is 40% or more and 50% or less, and the ratio of the total width Wo to the total thickness Do is 130% or more and 145% or less.

[0048] In other words, the fastener element 10 of this embodiment can have an appearance that is substantially the same as that of a conventional fastener element when viewed from above in a plan view (see, for example, Figures 1 and 2) when the fastener element 10 is formed with an overall length Lo and an overall thickness Do that are the same as those of a conventional metal fastener element.

[0049] At the same time, in the fastener element 10 of this embodiment, the total thickness Do of the fastener element 10 is formed to have the above-mentioned ratio with respect to each of the total length Lo and the total thickness Do. As a result, the total width Wo of the fastener element 10 of this embodiment can be reduced by about 30% compared with that of a conventional metal fastener element.

[0050] For example, in the fastener element 10 of this embodiment, when the average value of the total length Lo of the multiple fastener elements 10 is 2.8 mm or more and 3.0 mm or less, and / or when the average value of the total thickness Do of the multiple fastener elements 10 is 0.9 mm or more and 1.1 mm or less, the average value of the total width Wo of the multiple fastener elements 10 can be 1.3 mm or more and 1.5 mm or less. Note that the average values ​​of the total length Lo, total thickness Do, and total width Wo of the fastener element 10 may include an error of ±0.05 mm.

[0051] Therefore, compared with slide fasteners having conventional metal fastener elements, the slide fastener 1 having the fastener element 10 of this embodiment can have a similar appearance and can reduce the weight of the slide fastener 1. Furthermore, by reducing the overall width Wo of the fastener element 10, the basic unit of the fastener element 10 can be reduced, thereby reducing the manufacturing cost of the slide fastener 1. Furthermore, as the slide fastener is made lighter, costs for transporting the slide fastener and the slide fastener products (for example, clothing, etc.) can be reduced, and the environmental load caused by transportation, etc. can be reduced.

[0052] Specifically, in the fastener stringer 2 having the plurality of fastener elements 10 of this embodiment, for example, when the average value of the dimension of the total length Lo of the fastener elements 10 is 2.8 mm or more and 3.0 mm or less, the total weight of the plurality of fastener elements 10 attached per 10 m of length in the front-to-rear direction of the fastener stringer 2 (i.e., tape length) can be formed to be 93 g or less by reducing the weight by reducing the total width Wo of the fastener elements 10. In this case, the total weight of the plurality of fastener elements 10 in the fastener stringer 2 does not include the weight of the fastener tape 3.

[0053] In addition, the fastener element 10 of this embodiment has a unique shape and / or dimensions as described below in order to reduce the overall width Wo of the fastener element 10 as described above while ensuring the attachment strength when the fastener element 10 is attached to the fastener tape 3.

[0054] The interlocking head 20 of the fastener element 10 has a base portion 21, an engaging recess 23 recessed forward from the flat rear end surface (first surface) of the base portion 21, and an engaging protrusion 22 protruding forward from the front end portion of the base portion 21.

[0055] The base portion 21 of the interlocking head portion 20 has an element tip surface 21a facing inward in the left-right direction of the slide fastener 1, and a pair of head side surfaces 21b arranged on both sides in the element width direction. The base portion 21 has a curved surface that curves so as to smoothly connect the element tip surface 21a and the head side surfaces 21b of the base portion 21 in a front view (FIG. 3) or a rear view (FIG. 4) of the fastener element 10 when the fastener element 10 is viewed from the front-rear direction of the slide fastener 1.

[0056] The head side surface 21b of the base portion 21 has a gradually increasing portion 21c that gradually increases the dimension of the head side surface 21b in the element thickness direction toward the body portion 30, for example, in a plan view of the fastener element 10 (Figure 5) when the fastener element 10 is viewed from above the slide fastener 1.

[0057] In a rear view (FIG. 4) of the fastener element 10, for example, the engagement recess 23 has a bottom surface portion 23a provided in the center portion of the engagement recess 23, a concave-side inner circumferential surface 23b formed between the bottom surface portion 23a and the rear end surface of the base portion 21, and an opening 24 that opens into the rear end surface of the base portion 21. In addition, an edge portion 25 is formed between the concave-side inner circumferential surface 23b and the rear end surface of the base portion 21 so as to surround the opening 24.

[0058] The bottom surface portion 23a of the engagement recess 23 has an elliptical or oval shape that is long in the element width direction, or a shape similar thereto, when viewed from the back (FIG. 4) of the fastener element 10. This bottom surface portion 23a is formed perpendicular or approximately perpendicular to the element thickness direction.

[0059] The concave-side inner peripheral surface 23b has a concave-side vertical inner peripheral surface 23c having a portion that slopes in the element length direction from the bottom surface portion 23a of the engagement recess 23 toward the tip portion of the interlocking head 20, and a concave-side horizontal inner peripheral surface 23d having a portion that slopes in the element width direction from the bottom surface portion 23a toward the side edge portion of the interlocking head 20. The tip portion of the interlocking head 20 means the end portion of the fastener element 10 on the interlocking head 20 side in the element length direction. The side edge portion of the interlocking head 20 means one end or the other end portion of the interlocking head 20 in the element width direction.

[0060] In this case, the concave-side vertical inner peripheral surface 23c is inclined at an inclination angle θ1 of 70° to 85° with respect to the element length direction (see FIG. 5). Note that, when the inclined portion of the concave-side vertical inner peripheral surface 23c is formed into a curved surface, for example, a concave curve, the inclination angle θ1 can be expressed by the angle at which a virtual tangent that contacts the center of the inclined portion of the concave-side vertical inner peripheral surface 23c in the element height direction is inclined with respect to the element length direction in a vertical cross-sectional view of the fastener element 10 passing through the center of the opening 24 in the element width direction.

[0061] The concave-side lateral inner peripheral surface 23d has two surfaces that intersect at different angles with respect to the element width direction in a cross-sectional view of the fastener element 10 passing through the center of the element length direction of the opening 24, for example (see FIG. 6). Specifically, the concave-side lateral inner peripheral surface 23d has a first lateral inner peripheral surface 23e that is adjacent to the rear end surface of the side edge portion (base portion 21) of the coupling head portion 20, and a second lateral inner peripheral surface 23f that is formed between the first lateral inner peripheral surface 23e and the bottom surface portion 23a.

[0062] The first horizontal inner peripheral surface 23e is formed so as to intersect with the element width direction at a larger angle than the second horizontal inner peripheral surface 23f. A bent portion is provided between the first horizontal inner peripheral surface 23e and the second horizontal inner peripheral surface 23f. For example, in this embodiment, the first horizontal inner peripheral surface 23e is disposed at an angle perpendicular or substantially perpendicular to the element width direction. In other words, the first horizontal inner peripheral surface 23e is disposed parallel or substantially parallel to the element thickness direction. The second horizontal inner peripheral surface 23f is disposed at an angle inclined with respect to the element width direction, for example, between 55° and 85°.

[0063] That is, in this embodiment, the concave side vertical inner surface 23c along the element length direction of the engagement recess 23 is formed by a surface with one type of inclination angle, but the concave side horizontal inner surface 23d along the element width direction has two types of surfaces with different inclination angles via a bend.

[0064] In this way, the concave-side horizontal inner peripheral surface 23d has two surfaces (inner peripheral surfaces) at different angles from each other, which makes it easier to form the engaging recess 23 with a larger internal space. As a result, when performing press working to form the engaging protrusion 22 and the engaging recess 23 in the element material in the manufacturing process of the fastener element 10 described later, even if the element material is formed to be narrow overall so that the overall width Wo of the fastener element is small, an appropriate amount of metal material can be moved by forming the engaging recess 23. Therefore, the engaging protrusion 22 can be formed into a shape that stably protrudes forward by an appropriate protrusion amount relative to the positions of the front end surfaces of the body portion 30 and the leg portion 40, for example.

[0065] Here, for example, in a cross-sectional view of the fastener element 10 at the center of the opening 24 in the element length direction, when an imaginary straight line is extended to connect the portion where the rear end surface of the base portion 21 and the first horizontal inner circumferential surface 23 e intersect (a side edge portion 25 c described later) and the portion where the second horizontal inner circumferential surface 23 f and the bottom surface portion 23 a intersect, the inclination angle of the imaginary straight line with respect to the element width direction is defined as the inclination angle θ2 of the concave-side horizontal inner circumferential surface 23 d (see FIG. 6). In this case, the concave-side horizontal inner circumferential surface 23 d is formed so that the inclination angle θ2 is 65° or more and 85° or less.

[0066] As shown in Figure 4, the edge portion 25 of the engagement recess 23 has a tip edge portion 25a arranged at the tip portion of the interlocking head 20, a base edge portion 25b arranged at the base end portion close to the body portion 30 of the interlocking head 20, and a pair of side edge portions 25c arranged between both ends of the tip edge portion 25a and both ends of the base edge portion 25b.

[0067] The pair of side edge portions 25c of the engagement recess 23 are formed in a straight or substantially straight line along the element length direction. In the attachment process of attaching the fastener element 10 formed with a small overall width Wo to the fastener tape 3, the tip edge portion 25a and the base edge portion 25b of the engagement recess 23 are formed in a curved shape that is smoothly curved convexly toward the tip portion of the fastener element 10 by pressing the pair of leg portions 40 inward in the element width direction as described later to cause plastic deformation.

[0068] Because the tip edge portion 25a and the base edge portion 25b are formed in a curved shape in this manner, the engaging convex portion 22 of the mating fastener element 10 can be engaged with the engaging recess 23 at a portion closer to the tip of the engaging head 20, thereby making it easier to rotate the mutually interlocked left and right fastener stringers 2 around the engaging portion of the engaging convex portion 22 and the engaging recess 23, as will be described later (see Figure 7).

[0069] Furthermore, the tip edge portion 25a and the base edge portion 25b of the engagement recess 23 are formed in the shape of convex curved lines in the same direction, and a pair of side edge portions 25c are arranged parallel to each other, so that the opening 24 of the engagement recess 23 has a shape like a bent square when viewed from the back (FIG. 4) of the fastener element 10. As a result, when the left and right fastener elements 10 are interlocked, even if the fastener elements 10 are formed with a small element width, the engagement protrusion 22 of the mating fastener element 10 can be stably inserted to an appropriate depth into the engagement recess 23 of each fastener element 10, so that the interlocking strength of the left and right fastener elements 10 (or the lateral pull strength of the slide fastener 1) can be appropriately and stably ensured.

[0070] Here, for the opening 24 of the engagement recess 23 that opens onto the rear end surface of the base portion 21, the dimension in the element length direction at the center of the opening 24 in the element width direction (or the center of the bottom surface portion 23a in the element width direction) is defined as the central opening length Lc, and the dimension in the element length direction at the center of the opening 24 in the element length direction (or the center of the bottom surface portion 23a in the element length direction) is defined as the central opening width Wc (see Figure 4).

[0071] In this case, the ratio of the central opening width Wc to the central opening length Lc of the opening 24 is set to 100% or more and 130% or less. When the ratio of the central opening width Wc to the central opening length Lc is 100% or more, the mutually interlocked left and right fastener elements 10 can be rotated up to a large rotation angle θ7 around the engagement portion of the engaging protrusion 22 and the engaging recess 23 toward each of the front and back sides in the tape front-back direction, as shown in FIG.

[0072] For example, in the slide fastener 1 of this embodiment, the left and right fastener elements 10 can be rotated smoothly and largely toward the tape front surface side and the tape back surface side, respectively, up to a range in which the rotation angle θ7 of the fastener elements 10 is ±45° or more, preferably ±90° or more. In this case, for example, in Figure 7, the rotation angle θ7 when the right fastener element 10 rotates upward relative to the left fastener element 10 is represented by a positive angle, and the rotation angle θ7 when the right fastener element 10 rotates downward relative to the left fastener element 10 is represented by a negative angle.

[0073] Furthermore, the rotation angle θ7 of the fastener element 10 is preferably ±125° or less. That is, if the left and right fastener elements 10 rotate until the rotation angle θ7 becomes larger than ±125°, each fastener element 10 may come into contact with the other fastener tape 3 and may not be able to rotate any further. For this reason, the left and right fastener elements 10 can rotate smoothly as long as the rotation angle θ7 is within the range of ±125° or less.

[0074] By setting the ratio of the central opening width Wc to the central opening length Lc to be 130% or less, the pair of side edges of the interlocking head 20 can stably have appropriate strength. In the present invention, appropriate strength means a strength that allows the slide fastener 1 to be used stably over a long period of time.

[0075] The engaging protrusion 22 has a top end surface (top end) 22a that is arranged furthest from the rear end surface of the base portion 21 in the element thickness direction, and a convex side inclined surface (convex side outer peripheral surface) 22b formed between the top end surface 22a and the base portion 21.

[0076] The top end surface 22a of the engaging protrusion 22 has an oval or rounded rectangular shape, or a shape similar thereto, in a front view of the fastener element 10 (FIG. 3) when the fastener element 10 is viewed from the front side of the slide fastener 1. This top end surface 22a is formed perpendicular or approximately perpendicular to the element thickness direction. The top end surface 22a is formed with an area smaller than that of the bottom surface 23a of the engaging recess 23. The top end surface 22a of the engaging protrusion 22 is arranged forward of the positions of the front end surfaces (second surfaces) of the body 30 and leg portions 40 of the fastener element 10 in the element thickness direction (see FIG. 5).

[0077] The convex-side inclined surface 22b has a convex-side vertical inclined surface 22c that slopes in the element length direction from the top end surface 22a of the engaging protrusion 22 toward the tip of the interlocking head 20, and a convex-side horizontal inclined surface 22d that slopes in the element width direction from the top end surface 22a toward the side edge of the interlocking head 20. In this case, the convex-side vertical inclined surface 22c is inclined at an inclination angle θ3 of 50° to 65° with respect to the element length direction (see FIG. 5). The convex-side horizontal inclined surface 22d is inclined at an inclination angle θ4 of 60° to 75° with respect to the element width direction (see FIG. 6). The inclination angle θ4 of the convex-side horizontal inclined surface 22d is set larger than the inclination angle θ3 of the convex-side vertical inclined surface 22c.

[0078] In addition, when the convex side vertical inclined surface 22c or the convex side horizontal inclined surface 22d is formed in a curved shape, for example, such as being convexly curved, the inclination angle θ3 or the inclination angle θ4 can be expressed, for example, in a vertical cross-sectional view or a horizontal cross-sectional view of the fastener element 10, by the angle at which a virtual tangent line that contacts the convex side vertical inclined surface 22c or the convex side horizontal inclined surface 22d at the center in the element height direction is inclined with respect to the element length direction or the element width direction.

[0079] In the fastener element 10 of this embodiment, as described above, the inclination angle θ1 of the concave-side vertical inner circumferential surface 23c of the engaging recess 23 is 70° or more and 85° or less, and the inclination angle θ3 of the convex-side vertical inclined surface 22c of the engaging protrusion 22 is 50° or more and 65° or less (see FIG. 5). This makes it possible to stably form the engaging recess 23 and the engaging protrusion 22 having appropriate sizes in the element length direction in the fastener element 10. In addition, the strength of the tip portion of the interlocking head 20 can be stably ensured.

[0080] The inclination angle θ2 of the concave-side lateral inner peripheral surface 23d of the engaging recess 23 is 65° or more and 85° or less, and the inclination angle θ4 of the convex-side lateral inclined surface 22d of the engaging protrusion 22 is 60° or more and 75° or less. This makes it possible to stably form the engaging recess 23 and the engaging protrusion 22 having an appropriate size in the element width direction in the fastener element 10 formed with a small overall width Wo. Also, the strength of the pair of side edge portions of the interlocking head 20 can be stably ensured.

[0081] Furthermore, by setting the inclination angle θ1 to 70° or more, the inclination angle θ2 to 65° or more, the inclination angle θ3 to 50° or more, and the inclination angle θ4 to 60° or more, the engaging protrusion 22 of the mating fastener element 10 can be smoothly inserted to an appropriate depth into the engaging recess 23 of the fastener element 10. Therefore, the left and right fastener elements 10 can be firmly engaged with each other. In addition, the engaged state of the left and right fastener elements 10 can be stably maintained.

[0082] The inclination angle θ1 is larger than the inclination angle θ3, and the difference between the inclination angle θ1 and the inclination angle θ3 is 20° or more. The inclination angle θ2 is larger than the inclination angle θ4, and the difference between the inclination angle θ2 and the inclination angle θ4 is 5° or more. This makes it easier to provide an appropriate clearance between the inner circumferential surfaces of the engaging recesses 23 and the outer surfaces of the engaging protrusions 22 that engage with each other when the left and right fastener elements 10 are interlocked. In particular, the clearance can be gradually increased from the edge portion 25 toward the bottom portion 23a of the engaging recesses 23. This makes it easier to rotate the left and right fastener elements 10 that are interlocked with each other more smoothly, as shown in FIG.

[0083] In this embodiment, for example, when the engaging protrusion 22 of the interlocking head 20 is cut at the position of the front end surface of the leg 40 in the element thickness direction, the maximum value of the dimension in the element length direction at the cut surface of the engaging protrusion 22 is defined as the head cutting length Lh, and the maximum value of the dimension in the element width direction at the cut surface of the engaging protrusion 22 is defined as the head cutting width Wh (see Figures 5 and 6).

[0084] In this case, the ratio of the head cut width Wh to the head cut length Lh of the engaging protrusion 22 is set to 95% or more and 115% or less, preferably 98% or more and 110% or less. When the ratio of the head cut width Wh to the head cut length Lh is 95% or more, it is possible to stably ensure appropriate interlocking strength of the fastener elements 10 when the left and right fastener elements 10 are engaged with each other. When the ratio of the head cut width Wh to the head cut length Lh is 115% or less, it is possible to rotate the mutually interlocked left and right fastener stringers 2 so that the rotation angle θ7 is 45° or more.

[0085] In the interlocking head 20 of this embodiment, when the fastener element 10 is viewed from above or below the slide fastener 1 in a plan view (Figure 5) or a bottom view, an upwardly sloping portion 26 is provided between the convex side inclined surface 22b and the body portion 30, sloping upward from the convex side inclined surface 22b toward the body portion 30.

[0086] The upwardly inclined portion 26 of the interlocking head 20 is formed together with the engaging convex portion 22 and the engaging concave portion 23 by performing press working on the element material in the manufacturing process of the fastener element 10. By forming this upwardly inclined portion 26, it is possible to make it difficult for the metal material forming the interlocking head 20 to move toward the body portion 30 when press working is performed. Therefore, the interlocking head 20 can be stably formed with the engaging convex portion 22 and the engaging concave portion 23 in a predetermined shape.

[0087] The body 30 of the fastener element 10 is provided between the interlocking head 20 and a pair of legs 40. The body 30 has flat front and rear end faces facing the front-to-rear direction of the slide fastener 1, and a pair of body side faces facing the up-down direction of the slide fastener 1.

[0088] Each body side surface of the body 30 forms a continuous single plane with the head side surface 21b of the interlocking head 20 and the later-described leg outer side surfaces of the leg 40. In this case, the head side surface 21b, body side surface, and leg outer side surface arranged on one side in the vertical direction of the slide fastener 1, and the head side surface 21b, body side surface, and leg outer side surface arranged on the other side in the vertical direction are arranged along the element length direction and parallel to each other.

[0089] The body 30 of the fastener element 10 has a pair of connecting portions 31 to which a pair of leg portions 40 are respectively connected, and an inner thigh portion 32 disposed between the pair of connecting portions 31 (see FIG. 3). Here, the dimension of the inner thigh portion 32 of the body 30 in the element width direction is defined as the inner thigh width dimension Wi (see FIG. 4). In this case, the inner thigh width dimension Wi can be expressed as the difference between the overall width Wo of the fastener element 10 and twice the dimension of the connecting portion 31 in the element width direction (a first width dimension W1 described later). In other words, the inner thigh width dimension Wi can also be expressed as the minimum value of the dimension in the element width direction of the space between the pair of leg portions 40.

[0090] In the fastener element 10 of this embodiment, the inner crotch width dimension Wi of the body portion 30 is set to 0% or more and 46% or less, preferably more than 0% and 46% or less, and more preferably 5% or more and 30% or less of the total width Wo of the fastener element 10. In addition, the inner crotch width dimension Wi of the body portion 30 is set to be smaller than the maximum value of the dimension in the element width direction at the top end surface 22a of the engaging convex portion 22.

[0091] Since the inner crotch width dimension Wi is larger than 0% of the overall width Wo, the body portion 30 can be stably provided between the interlocking head portion 20 and the leg portion 40. In addition, the strength of the body portion 30 can be appropriately ensured. Therefore, the pair of leg portions 40 can be stably supported by the body portion 30, and the fastener element 10 with a small overall width Wo can be firmly fixed to the fastener tape 3. Furthermore, since the interlocking head portion 20 can be stably supported by the body portion 30, an appropriate interlocking strength (lateral pull strength) can be stably ensured when the left and right fastener elements 10 are interlocked. Note that the fastener element of the present invention may have a pair of legs 40 formed adjacent to each other without providing the inner crotch portion 32.

[0092] By making the inner thigh width dimension Wi 46% or less of the overall width Wo or smaller than the maximum value of the dimension in the element width direction at the top end surface 22a of the engaging protrusion 22, even if the overall width Wo of the fastener element 10 is reduced, the pair of legs 40 can be formed so that the dimension in the element width direction (first width dimension W1) at the connecting portion 31 is an appropriate size. Therefore, the fastener element 10 can be firmly attached to the fastener tape 3 with appropriate attachment strength (pull-out strength).

[0093] The pair of legs 40 extend from positions spaced apart in the element width direction of the body 30 toward one side in the element length direction (outside in the left-right direction). The core cord portion 3b of the fastener tape 3 is sandwiched and held between the pair of legs 40. Each leg 40 has a rear end surface (first surface) and a front end surface (second surface) facing the element thickness direction, a leg outer surface disposed on the outside in the element width direction, and a leg inner peripheral surface disposed on the inside in the element width direction.

[0094] The front and rear end surfaces of the legs 40 are perpendicular to the element thickness direction and parallel to each other, and form a single flat plane with the front and rear end surfaces of the body 30, respectively.

[0095] The inner peripheral surfaces of the legs 40 are in contact with the core cord portion 3b of the fastener tape 3, and are arranged to face each other with the core cord portion 3b sandwiched therebetween. In a front view (FIG. 3) or a rear view (FIG. 4) of the fastener element 10 seen from the front-rear direction of the slide fastener 1, a bent portion 41 is provided between the inner peripheral surfaces of the legs and the inner peripheral surfaces of the claws, which will be described later, of the claw portions 50. Due to this bent portion 41, the inner peripheral surfaces of the legs and the inner peripheral surfaces of the claws are arranged at different inclination angles relative to the element length direction.

[0096] Here, the dimension in the element width direction at the position of the connecting portion 31 of the leg portion 40 is defined as the first width dimension W1, and the dimension in the element width direction at the position of the bent portion 41 of the leg portion 40 is defined as the second width dimension W2. In this case, the ratio of the first width dimension W1 of the leg portion 40 to the total width Wo of the fastener element 10 is 35% or more and 45% or less, preferably 39% or more and 44% or less.

[0097] By making the ratio of the first width dimension W1 of the leg portion 40 to the total width Wo 35% or more, the strength of the leg portion 40 can be stably ensured and the core cord portion 3b of the fastener tape 3 can be tightly sandwiched between the leg portions 40. Therefore, the fastener element 10 can be firmly fixed to the fastener tape 3 with appropriate attachment strength.

[0098] Furthermore, when the pair of legs 40 are pressed inward in the element width direction to attach the fastener element 10 to the fastener tape 3, the connecting portion 31 of the leg portions 40 and its vicinity can be formed to be less likely to bend than the portion close to the claw portion 50 of the leg portions 40 (or the position of the bending portion 41 of the leg portions 40 and its vicinity). This makes it possible to reduce the load applied to the interlocking head portion 20 and the body portion 30 of the fastener element 10 by pressing. Furthermore, as a result, a plurality of fastener elements 10 (particularly the interlocking head portions 20 of the fastener elements 10) can stably have the same shape as one another. By setting the ratio of the first width dimension W1 of the leg portions 40 to the overall width Wo to 45% or less, fastener elements 10 having a small overall width Wo can be stably formed.

[0099] The ratio of the second width dimension W2 of the leg portion 40 to the overall width Wo of the fastener element 10 is 10% or more and 35% or less, preferably 20% or more and 30% or less. When the ratio of the second width dimension W2 of the leg portion 40 to the overall width Wo is 10% or more, the leg portion 40 can stably have appropriate strength.

[0100] Since the ratio of the second width dimension W2 of the leg portions 40 to the overall width Wo is 35% or less, the leg portions 40 can be formed thin, thereby reducing the cost and weight of the fastener element 10. Furthermore, when the pair of legs 40 are pressed inward in the element width direction to attach the fastener element 10 to the fastener tape 3, the portions of the legs 40 near the claw portions 50 can be made easier to bend than the connecting portion 31 of the leg portions 40 and its vicinity.

[0101] Therefore, the fastener element 10 can be stably attached to the fastener tape 3. In addition, by pressing the leg portion 40, the portion of the leg portion 40 close to the claw portion 50 can be actively bent, so that the load applied to the interlocking head portion 20 and the body portion 30 of the fastener element 10 by pressing can be reduced.

[0102] In the leg portion 40 of this embodiment, the ratio of the second width dimension W2 to the first width dimension W1 is 55% or more and 70% or less, preferably 60% or more and 67% or less. When the ratio of the second width dimension W2 to the first width dimension W1 is 55% or more, the strength of the leg portion 40 and the attachment strength of the fastener element 10 to the fastener tape 3 can be improved.

[0103] By making the ratio of the second width dimension W2 to the first width dimension W1 70% or less, the portions of the legs 40 close to the claw portions 50 can be stably formed thin, thereby more effectively realizing cost reduction and weight reduction of the fastener element 10. In addition, when a pressing force is applied to the pair of legs 40, the legs 40 can be appropriately plastically deformed. In particular, the portions of the legs 40 close to the claw portions 50 can be made easier to bend than the connecting portion 31 of the legs 40 and its vicinity. Therefore, the fastener element 10 can be firmly and stably fixed to the fastener tape 3.

[0104] The maximum value of the dimension in the element width direction of the space formed between the pair of leg portions 40 is 20% or more and 60% or less of the total width Wo of the fastener element 10. When the maximum value of the dimension in the element width direction of the space is 20% or more, it is possible to easily form each leg portion 40 narrow in the element width direction. In addition, the core cord portion 3b of the fastener tape 3 can be stably accommodated and held between the pair of leg portions 40. When the maximum value of the dimension in the element width direction of the space is 60% or less, it is possible to stably ensure the second width dimension W2 of the fastener element 10 and improve the strength of the leg portions 40.

[0105] 4, each leg 40 has a tapered portion 42 in the range in the element length direction from the connecting portion 31 of the leg 40 to the position where the bent portion 41 is provided, which gradually reduces the dimension of the leg 40 in the element width direction toward the position of the bent portion 41. By providing such a tapered portion 42 in the leg 40, the strength of the connecting portion 31 of the leg 40 and the portion in the vicinity thereof can be appropriately ensured, and the portion of the leg 40 near the claw portion 50 can be formed so as to be easily bent by pressure.

[0106] In particular, in the present embodiment, the gradually tapering portion 42 of the leg portion 40 is provided continuously over the entire length from the connecting portion 31 of the leg portion 40 to the position where the bent portion 41 is provided. In other words, each leg portion 40 is formed such that the dimension of the leg portion 40 in the element width direction decreases continuously from the connecting portion 31 of the leg portion 40 to the position where the bent portion 41 is provided.

[0107] In this case, the gradually tapering portion 42 of the leg portion 40 has a first gradually tapering portion 42a extending from the connecting portion 31 of the leg portion 40 and a second gradually tapering portion 42b extending from the first gradually tapering portion 42a to the bent portion 41 and gradually reducing the dimension of the leg portion 40 in the element width direction more gradually than the first gradually tapering portion 42a. In this case, the first gradually tapering portion 42a is formed so that the inner peripheral surface of the leg is arranged in a straight line or a curved line when viewed from the front (FIG. 3) or the back (FIG. 4) of the fastener element 10. The second gradually tapering portion 42b is formed so that the inner peripheral surface of the leg is arranged in a straight line when viewed from the front (FIG. 3) or the back (FIG. 4) of the fastener element 10.

[0108] By providing such gradually tapered portions 42 on the legs 40, the strength of the legs 40 can be more appropriately ensured, and when the legs 40 are pressed from the outside in the width direction, the portions of the legs 40 near the claw portions 50 can be easily and stably bent. As a result, the attachment strength of the fastener elements 10 to the fastener tape 3 can be improved.

[0109] In the present invention, each leg 40 of the fastener element 10 may be formed by partially providing a portion where the dimension of the leg 40 in the element width direction is gradually reduced. That is, each leg 40 may have a portion where the dimension of the leg 40 in the element width direction is constant in the range from the connecting portion 31 of the leg 40 to the position where the bent portion 41 is provided. Also, the gradually reduced portion 42 may be formed so that the inner peripheral surface of the leg 40 is arranged in a continuous straight line from the connecting portion 31 of the leg 40 to the position of the bent portion 41, or in a curved line curved at a constant curvature.

[0110] In the fastener element 10 of this embodiment, the leg forming angle θ5 formed between the inner peripheral surface of the inner crotch portion 32 of the body portion 30 and the inner peripheral surface of the leg portion 40 is 105° or more and 125° or less. By making the leg forming angle θ5 105° or more, it is possible to easily form the leg portion 40 thin in the element width direction. Therefore, it is possible to easily reduce the weight of the fastener element 10.

[0111] By setting the leg formation angle θ5 to 125° or less, the leg 40 is prevented from becoming too thin, and the strength of the leg 40 can be stably ensured. In addition, the dimension in the element length direction from the connecting portion 31 of the leg 40 to the position of the bent portion 41 (first length dimension L1 described later) can be appropriately ensured. Therefore, when the pair of legs 40 are pressed toward the inside in the element width direction to attach the fastener element 10 to the fastener tape 3, the leg 40 can be smoothly and stably plastically deformed. As a result, the attachment strength of the fastener element 10 to the fastener tape 3 can be improved.

[0112] The pair of claws 50 extend inward in the element width direction from the tip of each leg 40. Each claw 50 is formed to have the same dimension in the element thickness direction as the leg 40. The fastener tape 3 (tape body 3 a) is sandwiched between the pair of claws 50.

[0113] Each claw portion 50 has a rear end surface (first surface) and a front end surface (second surface) perpendicular to the element thickness direction, an inner claw surface that contacts the core string portion 3b of the fastener tape 3, a claw tip surface facing inward in the element width direction, and an outer element end surface facing in the direction away from the interlocking head 20 in the element length direction (outward in the left-right direction of the slide fastener 1).

[0114] The inner peripheral surface of the claw portion 50 is disposed between the inner peripheral surface of the leg portion 40 and the tip surface of the claw when viewed from the front (FIG. 3) or the rear (FIG. 4) of the fastener element 10. The inner peripheral surface of the claw is inclined with respect to the inner peripheral surface of the leg portion 40 via the bent portion 41.

[0115] The inner peripheral surface of the claw is inclined at an inclination angle θ6 of 50° or more and 70° or less, preferably 55° or more and 65° or less, with respect to the element length direction. When the inclination angle θ6 is 50° or more, and particularly when the inclination angle θ6 becomes larger, the claw portion 50 of the fastener element 10 can strongly press down on the core cord. Therefore, the fastener element 10 can be firmly fixed to the fastener tape 3, and the attachment strength of the fastener element 10 to the fastener tape 3 can be increased.

[0116] By setting the inclination angle θ6 to 70° or less, it is possible to easily process the substantially Y-shaped wire rod (Y bar) used in manufacturing the fastener element 10. In addition, since the cross section of the wire rod can be stably formed into a constant substantially Y-shaped shape, it is possible to stably manufacture a plurality of fastener elements having predetermined shapes. Specifically, the claw portion 50 of the fastener element 10 of this embodiment has a claw inner peripheral surface formed with an inclination angle θ6 of 60°.

[0117] The claw tip surfaces of the claw portions 50 are formed along the element length direction. The fastener tape 3 is sandwiched and held between the claw tip surfaces of the pair of claw portions 50. In this case, the distance between the claw tip surfaces is formed so that the dimension in the element width direction is smaller than the inner thigh width dimension Wi of the body portion 30.

[0118] The element outer end surfaces of the claw portions 50 are arranged along the element width direction (vertical direction) in a front view (FIG. 3) or a rear view (FIG. 4) of the fastener element 10, and are perpendicular to the claw tip surfaces of the claw portions 50. The element outer end surfaces are continuous with the outer leg surfaces of the leg portions 40 via a curved surface.

[0119] In the fastener element 10 of this embodiment, the dimension in the element length direction from the position of the connecting portion 31 of the leg portion 40 to the position of the bent portion 41 is defined as a first length dimension L1. The maximum value of the dimension in the element length direction from the position of the bent portion 41 to the element outer end surface of the claw portion 50 is defined as a second length dimension L2 (see FIG. 4).

[0120] In this case, the ratio of the first length dimension L1 to the total length Lo of the fastener element 10 is 25% or more and 35% or less. By making the ratio of the first length dimension L1 to the total length Lo 25% or more and the ratio of the second width dimension W2 to the first width dimension W1 of the leg portions 40 70% or less, it is possible to easily form each leg portion 40 elongated in the element length direction. Furthermore, when the pair of legs 40 are pressed toward the inside in the element width direction to attach the fastener element 10 to the fastener tape 3, it is possible to easily plastically deform the leg portions 40.

[0121] By setting the ratio of the first length dimension L1 to the total length Lo to be 35% or less, the dimension of the coupling head 20 in the element length direction of the fastener element 10 and the second length dimension L2 can be appropriately secured.

[0122] The ratio of the second length dimension L2 to the total length Lo of the fastener element 10 is 10% or more and 25% or less, preferably 15% or more and 20% or less. When the ratio of the second length dimension L2 to the total length Lo is 10% or more, the strength of the claw portion 50 can be appropriately ensured. As a result, the fastener element 10 can be firmly fixed to the fastener tape 3, and the attachment strength of the fastener element 10 to the fastener tape 3 can be increased.

[0123] By having the ratio of the second length dimension L2 to the total length Lo be 25% or less, the first length dimension L1 of the fastener element 10 can be appropriately secured, making it easier to plastically deform the leg portion 40 when attaching the fastener element 10 to the fastener tape 3.

[0124] In the fastener element 10 of this embodiment, the ratio of the second length dimension L2 to the first length dimension L1 is 55% or more and 80% or less, preferably 60% or more and 75% or less. When the ratio of the second length dimension L2 to the first length dimension L1 is 55% or more, the strength of the claw portion 50 can be appropriately ensured, and the attachment strength of the fastener element 10 to the fastener tape 3 can be increased. When the ratio of the second length dimension L2 to the first length dimension L1 is 80% or less, the first length dimension L1 can be appropriately ensured, and the leg portions 40 of the fastener element 10 can be stably plastically deformed.

[0125] In the fastener element 10 of this embodiment, in order to ensure the attachment strength of the fastener element 10 to the fastener tape 3, as described above, the shape of the body 30, the shape of the leg 40, the shape of the claw 50, the ratio of the inner thigh width dimension Wi of the body 30, the ratios of the first width dimension W1 and the second width dimension W2 of the leg 40, the size of the spacing between the legs 40, the leg formation angle θ5, the inclination angle θ6, and the ratios of the first length dimension L1 and the second length dimension L2 of the fastener element 10 are controlled.

[0126] However, in the present invention, by controlling at least one item, preferably two or more items, related to the leg portions 40 and claw portions 50 of the fastener element 10 among the multiple items described above, it is possible to appropriately ensure the attachment strength of the fastener element 10 to the fastener tape 3. For example, in the fastener element 10 of this embodiment, by appropriately setting at least one of the dimensions of the leg portions 40 in the element width direction and the element length direction and the inclination angle θ6, the fastener element 10 can have an appropriate attachment strength (for example, an attachment strength of 60 N or more).

[0127] A method for manufacturing the fastener element 10 according to the present embodiment as described above will be described. First, a long metal wire containing copper and zinc in the above-described predetermined contents is prepared. In this embodiment, a wire having a circular cross section is prepared as the metal wire. In the present invention, the cross-sectional shape of the prepared metal wire is not particularly limited.

[0128] Next, the prepared metal wire is rolled multiple times to form a metal wire (Y bar) having a substantially Y-shaped cross section. Subsequently, the obtained metal wire is sliced ​​to a predetermined thickness, as described in Patent Document 1, for example. Thereafter, the element material is pressed using an element forming device equipped with a forming punch and a forming die, to produce the fastener element 10.

[0129] Then, the manufactured multiple fastener elements 10 are sent to a tape attachment process and attached to the fastener tape 3. In this tape attachment process, with the tape side edge portion including the core string portion 3b of the fastener tape 3 inserted between the pair of leg portions 40 of the fastener element 10, the pair of leg portions 40 are pressed inward in the element width direction so as to approach each other.

[0130] As a result, the leg portions 40 of the fastener element 10 are plastically deformed, the fastener element 10 has the shape shown in Figures 3 to 6, and a part of the fastener tape 3 is sandwiched and held between the pair of leg portions 40 of the fastener element 10. As a result, the fastener element 10 can be attached to the fastener tape 3.

[0131] In this tape attachment process, by attaching a plurality of fastener elements 10 to the tape side edge of the fastener tape 3 at regular intervals, a fastener stringer 2 can be manufactured in which an element row 4 is formed on the tape side edge of the fastener tape 3.

[0132] Thereafter, the manufactured fastener stringers 2 are combined in pairs, and the first fastening member 5, the second fastening member 6, and the slider 7 are attached to the combined fastener stringer 2, thereby manufacturing the slide fastener 1 of this embodiment shown in Figure 1.

[0133] In the present invention, there are no particular limitations on the manufacturing methods of the fastener element 10, the fastener stringer 2, and the slide fastener 1. The fastener element 10, the fastener stringer 2, and the slide fastener 1 of this embodiment may be manufactured using a method other than the above-described method.

[0134] In the slide fastener 1 of this embodiment manufactured by the method described above, each fastener element 10 is formed in the shape and size described above, and is therefore firmly and securely attached to the fastener tape 3. Therefore, the attachment strength of the fastener elements 10 to the fastener tape 3 can be stably ensured at a size appropriate for use of the slide fastener 1.

[0135] For example, even if the fastener element 10 has an elongated shape such that the average value of the total length Lo is 2.8 mm or more and 3.0 mm or less and the average value of the total width Wo is 1.3 mm or more and 1.5 mm or less (see Figures 3 and 4), each fastener element 10 can stably have an appropriate attachment strength of 60 N or more to the fastener tape 3.

[0136] Furthermore, the fastener element 10 of this embodiment is formed with a smaller ratio of the total width Wo to the total length Lo of the fastener element 10 and a smaller ratio of the total width Wo to the total thickness Do of the fastener element 10 compared to conventional general metal fastener elements.

[0137] This allows the weight of the slide fastener 1 to be reduced. For example, the fastener element 10 of this embodiment can be made 15% or more, preferably 19% or more, lighter per fastener element 10 than a conventional fastener element having the same overall length Lo and overall thickness Do and formed from the same copper-zinc alloy. As a result, the costs required for transporting metal materials and transporting slide fastener products can be reduced. Furthermore, the basic unit of the fastener element 10 can be reduced, thereby reducing the manufacturing cost of the slide fastener 1. Furthermore, the environmental burden caused by transportation, etc. can be reduced, which can contribute to the SDGs (Sustainable Development Goals).

[0138] Furthermore, clothing such as jeans has a front opening called a fly, and the slide fastener 1 is sometimes used in the front opening. Also, the slide fastener 1 is sometimes used in the opening of a pocket of the clothing, and a flap is sometimes attached to cover the opening.

[0139] In such clothing, by attaching the slide fastener 1 of this embodiment to the front opening portion, the opening of a pocket, etc., the fastener element 10 of this embodiment is formed with a small overall width Wo of the fastener element 10 as described above, so that the thickness of the front opening portion and the thickness of the portion to which the flap is attached can be reduced. In addition, as will be described later, the slide fastener 1 of this embodiment has excellent flexibility. Therefore, by using the slide fastener 1 of this embodiment, it is possible to provide clothing that is more comfortable to wear and easier to wear than conventional clothing.

[0140] In the slide fastener 1 of this embodiment, the overall width Wo of the fastener elements 10 is small, and the engaging recesses 23 and the engaging protrusions 22 of the fastener elements 10 are formed in the above-mentioned shapes and dimensions. As a result, when the left and right fastener elements 10 are interlocked, one of the left and right fastener elements 10 can be rotated relative to the other around the engaging portion between the engaging protrusions 22 and the engaging recesses 23 of the fastener elements 10 in the front and back directions of the fastener tape 3 within a wide angle range, as shown in FIG.

[0141] Specifically, in the fastener element 10 of this embodiment, as described above, the engagement recess 23 is formed so that the ratio of the central opening width Wc to the central opening length Lc at the opening 24 of the engagement recess 23 is 100% or more and 130% or less. Also, the engagement protrusion 22 is formed so that the ratio of the head cut width Wh to the head cut length Lh of the engagement protrusion 22 is 95% or more and 115% or less.

[0142] In this way, the engaging recesses 23 and the engaging protrusions 22 are formed in the interlocking head 20 of each fastener element 10, so that when the left and right fastener elements 10 are interlocked, the engaging protrusions 22 of the mating fastener element can be easily rotated in the engaging recesses 23 of the fastener element 10. Therefore, the left and right fastener elements 10 can be smoothly rotated with a light force around the engaging portions of the engaging protrusions 22 and the engaging recesses 23.

[0143] Furthermore, in this embodiment, by reducing the overall width Wo of the fastener element 10, when the fastener element 10 is rotated as described above, the angle at which the fastener element 10 can rotate before interfering with the mating fastener tape 3 can be expanded.

[0144] For example, in the slide fastener 1 of this embodiment, one of the left and right fastener elements 10 can be rotated significantly relative to the other fastener element 10 toward both the tape surface side and the tape back side, to a range in which the rotation angle θ7 of the fastener element 10 is 45° or more, preferably 90° or more.

[0145] In this way, in the slide fastener 1 of this embodiment, even when the left and right element rows 4 are firmly interlocked with each other, each fastener element 10 can easily rotate relative to the mating fastener element 10. As a result, for example, when twisting the slide fastener 1 with the left and right element rows 4 interlocked with each other, the above-mentioned rotation of the fastener elements 10 can be utilized, making it easier to twist the slide fastener 1.

[0146] Furthermore, in this embodiment, since the overall width Wo of the fastener element 10 is smaller than that of a slide fastener having, for example, conventional metal fastener elements, when the slide fastener 1 is bent in the tape front-to-back direction with the left and right element rows 4 interlocked, it is possible to make it difficult for the fastener element 10 to interfere with the fastener elements 10 interlocked in front and behind the fastener element 10. As a result, it is possible to make the slide fastener 1 easier to bend in the tape front-to-back direction.

[0147] In this way, the slide fastener 1 of this embodiment is formed so that it can be easily twisted because each fastener element 10 is rotatable, and is also formed so that it can be easily bent in the tape front-to-back direction, thereby exhibiting excellent flexibility. In addition, the suppleness of the slide fastener 1 can be improved.

[0148] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0149] (Examples and Comparative Examples) As the slide fastener 1 of the example and the slide fastener of the comparative example, slide fasteners 1 each having a pair of left and right fastener stringers 2 in which a plurality of fastener elements 10 having the total length Lo, total width Wo, and total thickness Do shown in Table 1 below are attached to the fastener tape 3 were manufactured. In this case, the fastener elements 10 of both the example and the comparative example are formed from a copper-zinc alloy having a copper content of 59.0% by mass or more and 71.5% by mass or less and a zinc content of 28.5% by mass or more and 41.0% by mass or less (specifically, a copper-zinc alloy having a copper content of 65% by mass and a zinc content of 35% by mass).

[0150] (Attachment strength test of fastener element 10) Next, the left and right fastener stringers 2 were separated from each other for the slide fastener 1 of the example and the slide fastener of the comparative example. Furthermore, the attachment strength of the fastener element 10 to the fastener tape 3 was measured for one of the separated fastener stringers 2 using a tensile tester 70 shown in Figure 8 as follows.

[0151] First, the fastener tape 3 is fixed by the clamper 71 of the tensile tester 70. This allows the fastener stringer 2 to be held in the tensile tester 70. At this time, the fastener stringer 2 is held so that the tape length direction of the fastener tape 3 is aligned horizontally and the tape width direction is aligned vertically.

[0152] Next, the interlocking head 20 of one fastener element 10 is gripped and fixed by the jig 72 of the tensile tester 70. At this time, fastener elements 10 other than the fastener element 10 to be measured may be removed from the fastener tape 3.

[0153] Thereafter, the jig 72 to which the fastener element 10 was fixed was pulled vertically upward at a constant pulling speed, and the resistance value applied to the jig 72 was measured until the fastener element 10 was pulled out from the fastener tape 3. Furthermore, the maximum value of the measured resistance value was taken as the attachment strength (pull-out strength) of the fastener element 10.

[0154] For each fastener stringer 2 of the example and comparative example, the above-described attachment strength test was performed on six fastener elements 10, and the average value of the attachment strength of the six measured fastener elements 10 was calculated.

[0155] Generally, if the attachment strength of the fastener element in a slide fastener is 55 N or more, the fastener element is firmly fixed to the fastener tape and the slide fastener can properly perform its functions, so the slide fastener can be distributed in the market as a good product that meets the quality standard for attachment strength.

[0156] Therefore, for each fastener stringer 2 of the examples and comparative examples, if the average value of the attachment strength calculated by the above-mentioned method was 55 N or more, it was evaluated as a good product "◯", and if it was less than 55 N, it was evaluated as a defective product "X". The evaluation results are shown in Table 1 below.

[0157] (Total weight of fastener elements 10 per 10 m) Each fastener stringer 2 of the examples and comparative examples was cut so that the tape length of the fastener tape 3 was 10 m. Next, all fastener elements 10 were pulled out from the fastener tape 3 of the cut fastener stringer 2. Thereafter, the total weight of all the pulled out fastener elements 10 was measured. The measured total weight of the fastener elements 10 is shown in Table 1 below.

[0158]

[0159] As shown in Table 1 above, the ratio of the total width Wo to the total length Lo and the ratio of the total width Wo to the total thickness Do in the fastener element 10 of the example were 48.8% and 140.0%, respectively, which were within the range of the present invention. Furthermore, as a result of calculating the average value of the attachment strength of the fastener elements 10 to the fastener tape 3 in the fastener stringer 2 of the example, it was confirmed that the fastener stringer 2 of the example was a good product with an average attachment strength of 55 N or more.

[0160] Furthermore, it was confirmed that in the fastener stringer 2 of the example, the total weight of the multiple fastener elements 10 attached per 10 m of the fastener stringer 2 was 93 g.

[0161] On the other hand, it was confirmed that in the fastener element of the comparative example, the ratio of the total width Wo to the total length Lo was greater than 50%, and the ratio of the total width Wo to the total thickness Do was greater than 145%. Also, in the fastener stringer of the comparative example, since the total width Wo of the fastener elements was large, although the average value of the fastener element attachment strength showed a value that was acceptable, the total weight of the multiple fastener elements attached per 10 m of the fastener stringer exceeded 100 g.

[0162] From the results of the above examples and comparative examples, it was confirmed that in the slide fastener 1 of the example, the fastener element 10 is firmly fixed to the fastener tape 3, and by reducing the overall width Wo of the fastener element 10, it is lighter than the slide fastener of the comparative example.

[0163] The present invention is not limited to the above-described embodiment, and various modifications are possible as long as they have substantially the same configuration as the present invention and provide similar effects.

[0164] For example, the fastener element 10 in the above-described embodiment is formed of a copper-zinc alloy. However, in the present invention, the material of the fastener element is not particularly limited as long as it is a metal, and the fastener element may be formed of a metal other than a copper-zinc alloy, such as an aluminum alloy.

[0165] REFERENCE SIGNS LIST 1 Slide fastener 2 Fastener stringer 3 Fastener tape 3a Tape body 3b Core cord portion 4 Element row 5 First fastening member 6 Second fastening member 7 Slider 10 Fastener element 20 Interlocking head portion 21 Base portion 21a Element tip surface 21b Head side surface 21c Gradually increasing portion 22 Engaging convex portion 22a Top end surface (top end portion) 22b Convex side inclined surface 22c Convex side vertical inclined surface 22d Convex side horizontal inclined surface 23 Engaging recess 23a Bottom surface portion 23b Concave side inner peripheral surface 23c Concave side vertical inner peripheral surface 23d Concave side horizontal inner peripheral surface 23e First horizontal inner peripheral surface 23f Second horizontal inner peripheral surface 24 Opening 25 Edge portion 25a Tip edge portion 25b Base end edge portion 25c Side edge portion 26 Upward inclined portion 30 Body portion 31 Connecting portion 32 Crotch portion 40 Leg portion 41 Bending portion 42 Gradually tapering portion 42a First gradually tapering portion 42b Second gradually tapering portion 50 Claw portion 70 Tensile testing machine 71 Clamp 72 Jig Do Overall thickness L1 First length dimension L2 Second length dimension Lc Center opening length Lh Head cutting length Lo Overall length W1 First width dimension W2 Second width dimension Wc Center opening width Wh Head cutting width Wi Crotch width dimension Wo Overall width θ1 to θ4 Inclination angle θ5 Forming angle θ6 Inclination angle θ7 Rotation angle

Claims

A metal fastener element attached to the fastener tape (3) of the slide fastener (1), The fastener element (10) has an engaging head (20) having a protrusion (22) and a recess (23), When the dimensions of the entire fastener element (10) in the element length direction and element width direction are defined as the entire length (Lo) and the entire width (Wo) of the fastener element (10), respectively, the ratio of the entire width (Wo) to the entire length (Lo) of the fastener element (10) is 40% or more and 50% or less, When the dimension in the element thickness direction of the part of the fastener element (10) excluding the engaging head (20) is defined as the total thickness (Do), the ratio of the total width (Wo) to the total thickness (Do) of the fastener element (10) is 130% or more and 145% or less. A fastener element characterized by: 　 The fastener element (10) has a body portion (30) extending from the engaging head portion (20) in the element length direction, a pair of leg portions (40) branching off and extending from the body portion (30), and a pair of claw portions (50) extending inward in the element width direction from the tip end of each of the leg portions (40), The inner peripheral surface of each of the claw portions (50) is inclined with respect to the inner peripheral surface of the leg portion (40) via a bent portion (41), The dimension of each leg portion (40) in the element width direction gradually decreases from the connecting portion (31) where the leg portion (40) is connected to the body portion (30) to the position of the bent portion (41). The fastener element according to claim 1. 　 When the dimension in the element width direction at the connecting portion (31) of each of the leg portions (40) is defined as a first width dimension (W1), and the dimension in the element width direction at the position of the bent portion (41) of each of the leg portions (40) is defined as a second width dimension (W2), the ratio of the first width dimension (W1) to the total width (Wo) of the fastener element (10) is 35% or more and 45% or less, The ratio of the second width dimension (W2) to the total width (Wo) of the fastener element (10) is 10% or more and 35% or less, The ratio of the second width dimension (W2) to the first width dimension (W1) is 55% or more and 70% or less. The fastener element according to claim 2. 　 When the difference between the overall width (Wo) of the fastener element (10) and twice the first width dimension (W1) is defined as an inner crotch width dimension (Wi), the ratio of the inner crotch width dimension (Wi) to the overall width (Wo) of the fastener element (10) is 0% or more and 46% or less. The fastener element according to claim 3. 　 When the dimension in the element length direction from the position of the connecting portion (31) of the leg portion (40) to the position of the bent portion (41) is defined as a first length dimension (L1), and the maximum value of the dimension in the element length direction from the position of the bent portion (41) to the outer end surface of the claw portion (50) facing the element length direction is defined as a second length dimension (L2), the ratio of the first length dimension (L1) to the total length (Lo) of the fastener element (10) is 25% or more and 35% or less, The ratio of the second length dimension (L2) to the total length (Lo) of the fastener element (10) is 10% or more and 25% or less, The ratio of the second length dimension (L2) to the first length dimension (L1) is 55% or more and 80% or less. The fastener element according to any one of claims 2 to 4. 　 The coupling head (20) has a first surface facing the element thickness direction of the coupling head (20) and on which the recess (23) is provided, The recess (23) has an opening (24) that opens to the first surface, When the dimension of the opening (24) in the element length direction at the center in the element width direction is defined as a central opening length (Lc), and the dimension of the opening (24) in the element width direction at the center in the element length direction is defined as a central opening width (Wc), the ratio of the central opening width (Wc) to the central opening length (Lc) is 100% or more and 130% or less, When the convex portion (22) of the coupling head (20) is cut at the position of a second surface of the leg portion (40) facing the element thickness direction, the dimension of the cut surface of the convex portion (22) in the element length direction is defined as a head cutting length (Lh) and the dimension of the cut surface of the convex portion (22) in the element width direction is defined as a head cutting width (Wh), the ratio of the head cutting width (Wh) to the head cutting length (Lh) is 95% or more and 115% or less. The fastener element according to any one of claims 2 to 5. 　 The recess (23) of the interlocking head (20) has a recessed-side vertical inner peripheral surface (23c) having a portion inclined along the element length direction from a bottom surface portion (23a) of the recess (23) toward a tip end portion of the interlocking head (20), and a recessed-side horizontal inner peripheral surface (23d) having a portion inclined along the element width direction from the bottom surface portion (23a) of the recess (23) toward a side edge portion of the interlocking head (20), The concave-side vertical inner peripheral surface (23c) is inclined at an inclination angle (θ1) of 70° to 85° with respect to the element length direction, The concave-side horizontal inner peripheral surface (23d) is inclined at an inclination angle (θ2) of 65° or more and 85° or less with respect to the element width direction, The convex portion (22) of the interlocking head portion (20) has a convex-side vertical inclined surface (22c) that is inclined from the top end surface of the convex portion (22) toward the tip end portion of the interlocking head portion (20) along the element length direction, and a convex-side horizontal inclined surface (22d) that is inclined from the top end surface of the convex portion (22) toward the side edge portion of the interlocking head portion (20) along the element width direction, The convex-side vertically inclined surface (22c) is inclined at an inclination angle (θ3) of 50° or more and 65° or less with respect to the element length direction, The convex side inclined surface (22d) is inclined at an inclination angle (θ4) of 60° to 75° with respect to the element width direction. The fastener element according to any one of claims 2 to 6. 　 The concave-side lateral inner peripheral surface (23d) has a first lateral inner peripheral surface (23e) adjacent to the end surface of the side edge portion of the coupling head portion (20), and a second lateral inner peripheral surface (23f) formed between the first lateral inner peripheral surface (23e) and the bottom surface portion (23a) of the recess (23), The first inner lateral surface (23e) is formed so as to have a larger angle intersecting with the element width direction than the second inner lateral surface (23f). The fastener element according to claim 7. 　 A fastener stringer comprising a plurality of fastener elements (10) according to any one of claims 1 to 8, and the fastener tape (3) to which the fastener elements (10) are attached. 　 When the average value of the total width (Wo) of the fastener elements (10) is 1.3 mm or more and 1.5 mm or less, the attachment strength of each fastener element (10) to the fastener tape (3) is 60 N or more. The fastener stringer according to claim 9. 　 A fastener stringer having a plurality of metal fastener elements (10) and a fastener tape (3) to which the fastener elements (10) are attached, When the average value of the dimension in the element length direction of the entire fastener element (10) is 2.8 mm or more and 3.0 mm or less, the total weight of the multiple fastener elements (10) attached per 10 m of the fastener stringer in the tape length direction of the fastener tape (3) is 93 g or less. A fastener stringer characterized by the above. 　 the metal is a copper-zinc alloy, The copper content in the copper-zinc alloy is 59% by mass or more and 71.5% by mass or less, The zinc content in the copper-zinc alloy is 28.5% by mass or more and 41% by mass or less. The fastener stringer according to claim 11.

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