Metal zipper fastener, and method for manufacturing metal zipper fastener

Abstract

The present invention aims to improve the appearance of the outer side of a metal zipper. The metal zipper for a zipper of the present invention has a meshing head (2) and left and right leg portions (3). The left and right leg portions have left and right leg portion bodies (31) extending from the meshing head, and left and right clamping portions (32) extending from the front end portions of the left and right leg portion bodies in a direction toward each other. The left and right leg portion bodies have a portion on the outer side thereof having only a shear surface (4) and no fracture surface (5) within a fixed width range. Since the outer side of the leg portion body has no fracture surface within the fixed width range, the appearance of the metal zipper is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to a metal fastener and a manufacturing method thereof. BACKGROUND

[0002] As one example of a manufacturing method of a metal fastener, there is known a manufacturing method which has: a concave-convex forming press working which plastically deforms a metal plate in a thickness direction thereof to form a meshing convex portion and a meshing concave portion of a meshing head portion of a metal fastener; and a blanking press working which blanks out the metal fastener as a product from the metal plate after the concave-convex forming press working (Patent Literature 1).

[0003] According to the manufacturing method disclosed in Patent Literature 1, in a hole of a female die used in the blanking press working, a chamfering process is applied to a curved surface having a radius of 0.01 mm to 1.0 mm at an entrance portion thereof, and is formed in parallel with a depth direction at an inner side of the chamfering with respect to the entrance portion. Further, a gap between a male die and the female die is set to 0.1 μm to 10 μm.

[0004] Further, according to the manufacturing method disclosed in Patent Literature 1, left and right leg portions of the blanked metal fastener are necessarily formed with a shear surface and a fracture surface. In detail, in the metal fastener, an entire outer side surface of the meshing head portion and the left and right leg portions is formed with the shear surface and the fracture surface, a proportion of the shear surface with respect to the total area is set to 80% or more, and a proportion of the fracture surface with respect to the total area is set to less than the remaining 20%. Further, since the fracture surface has a larger surface roughness than the shear surface, by increasing the proportion of the shear surface with respect to the total area, the appearance of the metal fastener is improved.

[0005] Figure 8 A metal fastener equivalent to that disclosed in Patent Literature 1 is shown. The figure is a copy of an image obtained by photographing a left side surface of a metal fastener la obliquely from an upper side to a lower side. In the figure, an outer side surface of a left leg portion 3a and a left side surface of a meshing head portion 2a are shown as the left side surface of the metal fastener la. Further, in the image, the side surface of the metal fastener is formed with a dark black portion and a white portion. The dark black portion is a shear surface, and the white portion is a fracture surface. In the figure, the dark black portion (shear surface 4a) is indicated with parallel, equally-spaced fine lines, and the white portion (fracture surface 5a) is indicated with white. (Note that this is a color distinction relating only to the side surface of the metal fastener la, and the white of a portion other than the outer side surface of the metal fastener la does not indicate the fracture surface 5a.) Further, according to the figure, the shear surface 4a occupies a large portion of the outer side surface of the left leg portion 3a (a portion other than a right edge portion), and the fracture surface 5a occupies a small portion of the outer side surface of the left leg portion 3a (the right edge portion).

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Laid-Open No. 2005-237532 SUMMARY

[0009] Problem to be solved by the invention

[0010] The present application has been made in view of the above-described actual situation, and aims to further improve the appearance of the outer side surface of the metal zipper tooth.

[0011] Means for solving the problem

[0012] The metal zipper tooth for a zipper according to the present application has engaging head portions and left and right leg portions. The left and right leg portions have left and right leg portion bodies extending from the engaging head portions in two branches, and left and right clamping portions extending from the front end portions of the left and right leg portion bodies in directions toward each other. On this basis, the left and right leg portion bodies have portions on the outer side surfaces thereof that have only a shearing surface and no breaking surface within a fixed width range.

[0013] The fixed width range means, for example, the following 1) and 2). 1) The fixed width range means a range corresponding to the core portion of the tape portion clamped by the left and right leg portion bodies. 2) The fixed width range means the entire outer side surface of the left and right leg portion bodies.

[0014] Further, the portions that have only a shearing surface and no breaking surface can be on the outer side surface of the leg portion body or not. Further, it is preferable that the outer side surface of the engaging head portion also have a portion that has only a shearing surface and no breaking surface.

[0015] The method for manufacturing the metal zipper tooth for a zipper according to the present application is premised on the formation of a concave-convex forming press working in which a metal plate is plastically deformed in the thickness direction thereof to form engaging convex portions and engaging concave portions of the engaging head portions of the metal zipper tooth, and a blanking press working in which the metal zipper tooth as a product is blanked from the metal plate after the concave-convex forming press working. Further, in the blanking press working, the outer shape of the engaging head portions of the metal zipper tooth is formed and the outer shape of the left and right leg portions is formed. The left and right leg portions have left and right leg portion bodies extending from the engaging head portions in two branches, and left and right clamping portions extending from the front end portions of the left and right leg portion bodies in directions toward each other.

[0016] On this basis, the manufacturing method of the metal fastener chain for a slide fastener according to the present application is characterized in that the die used in the blanking press working has an inclined portion having an inclined surface in a fixed width range in a portion of the entrance of the hole of the die and corresponding to the outer side surface of the left and right leg portion bodies, the inclined surface being inclined with respect to the depth direction of the hole in a state in which the width of the hole is narrowed toward the inside of the hole.

[0017] The fixed width range means, for example, the following 3) and 4). 3) The fixed width range means a range corresponding to the core of the tape portion held by the left and right leg portion bodies. 4) The fixed width range means the entire outer side surface of the left and right leg portion bodies.

[0018] Further, the portion having only the shearing surface and not having the breaking surface can be formed on the outer side surface of the leg portion body or not. Also, it is preferable that the inclined portion be provided in the die used in the blanking press working in a portion of the entrance of the hole of the die and corresponding to the outer side surface of the engaging head portion.

[0019] Regardless of the details of the inclined surface, it is preferable that the inclined surface be inclined with respect to the depth direction of the hole at an angle θ satisfying the following relation 1: 0° < θ ≦ 30°. More preferably, the relation 1 is as follows. Relation 1: 10° ≦ θ ≦ 28°.

[0020] Effects of the invention

[0021] Since the metal fastener chain for a slide fastener according to the present application has only the shearing surface and not the breaking surface in the fixed width range of the outer side surface of the left and right leg portion bodies, the appearance of the metal fastener chain is improved compared to the metal fastener chain having the breaking surface in the outer side surface.

[0022] Further, the manufacturing method of the metal fastener chain for a slide fastener according to the present application forms the inclined portion having the inclined surface inclined with respect to the depth direction of the hole in a state in which the width of the hole is narrowed toward the inside of the hole in the entrance of the hole of the die, and thus, in the blanking press working, the fixed width range in the outer side surface of the left and right leg portion bodies is formed in a state in which the fixed width range is pressed by the inclined surface during the period in which the inclined surface is passed, as a result of which the fixed width range in the outer side surface of the left and right leg portion bodies is not broken (no trace of peeling is formed) but only the shearing surface is formed in the thickness range of the metal fastener chain, and the appearance of the outer side surface of the left and right leg portion bodies is improved compared to the manufacturing method using the press working in which the metal fastener chain is only punched out of the metal plate. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a perspective view showing the metal fastener chain for a slide fastener according to the first embodiment of the present application;

[0024] Figures 2(A) and 2(B) are accompanying figures showing a comparison of the metal zipper teeth in the open and closed states of the left and right feet;

[0025] Figure 3 This is a left-side view of the metal zipper teeth;

[0026] Figure 4 This is a top view showing a zipper that uses metal zipper teeth;

[0027] Figure 5 This is a top view showing a method for manufacturing metal zipper teeth for zippers according to the first embodiment of the present invention;

[0028] Figure 6 yes Figure 5 Sectional view of line VI-VI;

[0029] Figure 7 yes Figure 5 Sectional view along line VII-VII;

[0030] Figure 8 This is a left-side view showing an example of an existing zipper with metal zipper teeth. Detailed Implementation

[0031] like Figure 4 As shown, the zipper is fixed to the opposing side edges of a pair of strap portions 9 by metal zipper teeth 1 at intervals. As a result, multiple metal zipper teeth 1 are arranged in a row along the length of the opposing side edges of each strap portion 9. This row of metal zipper teeth 1 is called a tooth row. By moving a zipper head (not shown) in one direction along the opposing tooth rows, the metal zipper teeth 1 of the opposing tooth rows engage with each other, thereby closing the pair of strap portions 9. By moving the zipper head in the opposite direction, the engagement of the metal zipper teeth 1 of the opposing tooth rows disengages, thereby opening the pair of strap portions 9.

[0032] like Figure 1 As shown in Figure 2, the metal zipper tooth 1 of the first embodiment of the present invention is composed of an engaging head 2 and a pair of legs 3. The engaging head 2 is used to engage with other metal zipper teeth 1, and the pair of legs 3 are installed in the state of holding the side edge of the strap 9, and extend from the engaging head 2 into two branches. It should be noted that the metal zipper tooth 1 is, for example, made of aluminum alloy.

[0033] In the metal fastener 1, the directions required for explanation are defined as follows with reference to FIG. 2. The "left-right direction" is the direction in which the pair of leg portions 3 are separated from each other, and is the left-right direction in FIG. 2. Note that the left-right direction coincides with the thickness direction of the tape portion 9. The "up-down direction" is the direction of the engagement head portion 2 with respect to the pair of leg portions 3, and is the up-down direction in FIG. 2. Note that the up-down direction coincides with the width direction of the tape portion 9. The "front-rear direction" is the direction orthogonal to the left-right direction and the up-down direction, and is the direction orthogonal to the plane of FIG. 2. In addition, the "front-rear direction" also refers to the thickness direction of the metal fastener 1.

[0034] The engagement head portion 2 has a head body 21, engagement protrusions 22 that are concave and convex on opposite surfaces of the head body 21, and engagement recesses 23. That is, the engagement head portion 2 has (see FIG. 2) the engagement protrusions 22 that protrude on the opposite surfaces of the head body 21, and the engagement recesses 23 that are recessed on the opposite surfaces of the head body 21. Note that in the present embodiment, the metal fastener 1 having the engagement protrusions 22 and the engagement recesses 23 on the opposite surfaces of the head body 21 is described, but the present application can also be applied to a metal fastener having only the engagement recesses on one surface and only the engagement protrusions on the other surface of the head body 21. Figure 3 ) the engagement protrusions 22 that protrude on the opposite surfaces of the head body 21, and the engagement recesses 23 that are recessed on the opposite surfaces of the head body 21. Note that in the present embodiment, the metal fastener 1 having the engagement protrusions 22 and the engagement recesses 23 on the opposite surfaces of the head body 21 is described, but the present application can also be applied to a metal fastener having only the engagement recesses on one surface and only the engagement protrusions on the other surface of the head body 21.

[0035] In the head body 21, the lower portion thereof is provided as a joint portion 25 for joining the pair of leg portions 3, and the upper side of the joint portion 25 is provided as a flat plate portion 26 that extends upward more than the opposite surfaces of the joint portion 25 in a stepped recessed state. The joint portion 25 is formed in a U shape that is open toward the upper side on the opposite surfaces. On the joint portion 25 and the pair of leg portions 3, the front and rear surfaces of the metal fastener 1 (the two surfaces in the thickness direction of the metal fastener 1) are parallel planes. In more detail, the front surface of the joint portion 25 is a coplanar plane with the front surface of the pair of leg portions 3, that is, is on the same plane, and the rear surface of the joint portion 25 is also a coplanar plane with the rear surface of the pair of leg portions 3, and is parallel to the front surface of the joint portion 25 and the front surface of the pair of leg portions 3. In the flat plate portion 26, the central portions of the opposite surfaces are provided as portions from which the engagement protrusions 22 protrude. The lower side (the leg portion 3 side) of the opposite surfaces of the flat plate portion 26 than the engagement protrusions 22 is formed as a surface that is recessed in a stepped manner compared to the engagement protrusions 22 and the joint portion 25, and as a result, the opposite surfaces of the flat plate portion 26 (the head body 21) are formed with the engagement recesses 23 surrounded by the engagement protrusions 22 and the joint portion 25.

[0036] The left and right leg portions 3 have: left and right leg portion bodies 31 extending from the engagement head portion 2; and left and right clamping portions 32 extending from the front end portions (lower end portions) of the left and right leg portion bodies 31 toward each other. FIG. 2(A) shows a state before the metal fastener 1 is attached to the tape portion 9. In this state, the left and right leg portion bodies 31 are formed in a shape in which the interval between the left and right thereof widens as it goes downward. FIG. 2(B) shows a state in which the metal fastener 1 is attached to the tape portion 9. In the tape portion 9, the side edge portion on the side opposite to the other tape portion 9 not shown is formed to be thicker than the opposite side. This thick portion is referred to as a core portion 9a. On the other hand, the portion adjacent to the core portion 9a that is thinner in thickness is referred to as a tape body portion 9b. That is, the tape portion 9 has the tape body portion 9b and the core portion 9a that is adjacent to one end in the width direction of the tape body portion 9b. Also, in the state of being attached to the tape portion 9, the left and right leg portion bodies 31 are formed in a shape in which most of the outer side surface thereof is substantially parallel in the vertical direction, and the core portion 9a is housed inside thereof. The left and right clamping portions 32 support the tape body portion 9b in a manner that the core portion 9a does not fall off. Further, in the state shown in FIG. 2(B), in the metal fastener 1, the faces (upper surface and lower surface) provided opposite to the vertical direction are set to be substantially parallel to the thickness direction of the tape portion 9, and the faces (outer side surfaces) provided opposite to the left and right directions are set to be substantially parallel to the width direction of the tape portion 9. On this basis, in the metal fastener 1, the corner portion C1 where the upper surface intersects with the left and right outer side surfaces is set to be a curved surface C1 that is smoothly continuous in a shape bulging in a circular arc shape, and the corner portion C2 where the lower surface intersects with the left and right outer side surfaces is also set to be a curved surface C2 that is smoothly continuous in a shape bulging in a circular arc shape.

[0037] The metal fastener 1 described above has, on the outer side surface of the left and right leg portion bodies 31, a fixed width range formed only by the shear faces 4 (hereinafter, referred to as "total shear face range" in the present specification). Further, the portion of the outer side surface of the metal fastener 1 other than the total shear face range has the shear faces 4 and the fracture faces 5. Among them, the following describes multiple examples in which the total shear face range is provided on the outer side surface of the metal fastener 1 using FIG. 2(B). The premise is that the state in which the metal fastener 1 is attached to the tape portion 9, that is, the state of FIG. 2(B) is the basis.

[0038] In the reference state, since the first example of the total shearing surface range of the metal zipper 1 is targeted at the outer side surface of the left and right leg portion bodies 31, it is as follows. In the reference state, the left and right clamping portions 32 of the metal zipper 1 are formed with a pair of clamping surfaces 32a that clamp the belt portion body portion 9b of the belt portion 9 in the thickness direction of the belt portion body portion 9b of the belt portion 9 and are parallel planar surfaces. From the end point of the clamping surface 32a on the core portion 9a side, a virtual line Ll is drawn in the thickness direction of the belt portion 9. The virtual line Ll is the first boundary line Ll that divides the total shearing surface range of the left and right leg portion bodies 31 and the portion other than the total shearing surface range.

[0039] In the reference state shown in Fig. 2(B), from the width direction end of the belt portion 9 in the space formed between the left and right leg portions 3, a virtual line L2 is drawn in the thickness direction of the belt portion 9. Also, the virtual line L2 is the second boundary line L2 that divides the total shearing surface range of the left and right leg portion bodies 31 and the portion other than the total shearing surface range.

[0040] Therefore, the total shearing surface range of the left leg portion body 31 refers to the range SI between the left side surface of the left leg portion body 31 and the left first boundary line Ll and the left second boundary line L2. Similarly, the total shearing surface range of the right leg portion body 31 refers to the range S2 between the right side surface of the right leg portion body 31 and the right first boundary line Ll and the right second boundary line L2. As such, the first example of the total shearing surface range of the metal zipper 1 is targeted at the leg portion body 31, and thus, is the range SI and S2 between the left and right first boundary lines Ll and the left and right second boundary lines L2, in other words, the range SI and S2 corresponding to the core portion 9a of the belt portion 9 clamped by the left and right leg portion bodies 31.

[0041] Further, in the reference state shown in Fig. 2(B), the second example of the total shearing surface range of the metal zipper 1 is targeted at the joint portion 25 of the engaging head portion 2 and the left and right leg portion bodies 31, and it is as follows. As described above, the front and rear surfaces of the U-shaped joint portion 25 that opens upward are formed on the same plane as the front and rear surfaces of the left and right leg portions 3. Also, from the end of the front and rear surfaces of the joint portion 25 farthest from the leg portions 3, a virtual line L3 is drawn in the thickness direction of the belt portion 9. The virtual line L3 is the third boundary line L3 that divides the total shearing surface range of the metal zipper 1 and the portion other than the total shearing surface range. Also, the second example of the total shearing surface range of the metal zipper 1 is the range S3 and S4 between the left and right first boundary lines Ll and the left and right third boundary lines L3, in other words, the shape in which the outer side surface of the engaging head portion 2 and the outer side surface of the left and right leg portion bodies 31 are continuous.

[0042] Furthermore, in the reference state shown in Figure 2(B), the third example of the total shear surface range of the metal zipper tooth 1 is based on the entire outer surface of the metal zipper tooth 1, therefore, as described below. As previously mentioned, in the metal zipper tooth 1, the upper surface is set to be approximately parallel to the thickness direction of the strip portion 9, and the upper left and right corner portions C1 are set as curved surfaces C1 with an arc-shaped bulge. A virtual line L4 is drawn from the uppermost point of this curved surface C1 in the thickness direction of the strip portion 9. This virtual line L4 is the upper limit boundary line L4 dividing the total shear surface range of the metal zipper tooth 1 and the portion other than the total shear surface range. Furthermore, as previously mentioned, in the metal zipper tooth 1, the lower surface is set to be approximately parallel to the thickness direction of the strip portion 9, and the lower left and right corner portions C2 are set as curved surfaces C2 with an arc-shaped bulge. A virtual line L0 is drawn from the lowermost point of this curved surface C2 in the thickness direction of the strip portion 9. The virtual line L0 is the lower boundary line L0 that divides the total shear surface area of ​​the metal zipper tooth 1 into the portion excluding the total shear surface area. Furthermore, the third example of the total shear surface area of ​​the metal zipper tooth 1 is the ranges S5 and S6 between the upper left and right boundary line L4 and the lower left and right boundary line L0, which in general refers to the entire left and right outer surfaces of the metal zipper tooth 1. More specifically, it is the shape where the entire outer surface of the left and right foot bodies 31 is continuous with the entire left and right outer surface of the engaging head 2. Additionally, the entire outer surface of the left and right foot bodies 31 refers to the ranges S7 and S8 between the lower left and right boundary line L0 and the second left and right boundary line L2.

[0043] The first to third examples of the total shear surface range indicated in the reference state shown in Figure 2(B) above are examples of setting the total shear surface range. The total shear surface range only needs to be set to cover a fixed width at least on the outer side of the foot body 31 and to cover the entire surface in the thickness direction of the metal zipper tooth 1. Preferably, the total shear surface range is set on the entire outer side of the zipper product (clothing, bag, etc.) that can be seen by the user when the zipper is installed.

[0044] in addition, Figure 1 , Figure 3 In China, it is also used with Figure 8 Similarly, the shear plane 4 is shown using parallel and equally spaced thin lines. It should be noted that... Figure 1 In this context, the entire outer surface of the left and right foot main bodies 31 and the entire outer surface of the joint 25 are defined as the total shear plane range. Figure 3 In this context, the entire left and right outer surfaces of the metal zipper teeth 1 are defined as the total shearing surface range. Furthermore, the outer surfaces of the left and right foot bodies 31 are formed only by shearing surfaces 4 that are sheared along the penetrating direction (front-back direction) of the space formed between the left and right foot bodies 3.

[0045] The surface roughness (arithmetical mean roughness) Ra of the shear face 4 is 1.0 a or less. Further, the surface roughness (arithmetical mean roughness) Ra of the fracture face 5 is greater than 1.0 a. This value is a value obtained by rounding off the second digit after the decimal point to the nearest whole number with respect to the unit a.

[0046] As shown in Figure 5 , in the manufacturing method of the metal fastener 1 of the first embodiment, the metal plate 7 is continuously manufactured into the metal fastener 1 of the first embodiment by intermittently stopping the metal plate 7 twice while conveying the metal plate 7 and applying press working during each of the two stopping periods. Figure 5 The respective letters A and B shown in Figure 5 indicate the positions of the respective press workings in the conveying path. Further, The hatched area in

[0047] is a working area in which press working is performed. The metal plate 7 is in a band shape, and its thickness corresponds to the thickness of the engaging head portion 2 and the joint portion 25 of the left and right leg portions 3. Figure 5 In the first press working indicated by A in

[0048] , a die not shown is used to plastically deform the metal plate 7 in the thickness direction thereof, thereby forming the engaging convex portion 22 and the engaging concave portion 23 of the engaging head portion 2 of the metal fastener 1. That is, the first press working is press working for forming the concave-convex of the engaging head portion 2. Figure 5 Next, Figure 5 the second press working indicated by B in Figure 1 is blanking press working for blanking the metal fastener 1 as a product from the metal plate 7 after the concave-convex forming press working. In more detail, in the second press working, the hatched area portion inside the single-dot chain line indicated in the drawing (the inside portion of the outer shape of the metal fastener 1) is blanked from the metal plate 7, thereby forming the outer shape of the metal fastener 1, that is, the outer shapes of the engaging head portion 2 and the left and right leg portions 3, as shown in

[0049] The cross-sectional view of the punch 11 and the die 12 used in the second press working (cross-sectional view of VI-VI line and VII-VII line of Figure 5 ) is as shown in Figure 6 and Figure 7The punch 11 forms the portion for blanking the metal plate 7 (pressing in) to a shape slightly smaller than the shape corresponding to both the engagement portions 25 of the left and right leg portions 3 and the engagement head portion 2 (to be described later, the shape of the inner side portion h2 of the hole h of the die 12). The portion of the die 12 for placing the metal plate 7 is formed with a width sufficient for stably placing the metal plate 7.

[0050] In the present specification, the side into which the metal fastener 1 enters at the time of blanking is described as an entrance portion hi and the inner side of the hole h with respect to the entrance portion hi is described as an inner side portion h2 throughout the circumference of the hole h of the die 12.

[0051] The inner side portion h2 is formed in a shape corresponding to the shape of the metal fastener 1 and is formed as a face parallel to the depth direction.

[0052] The entrance portion hi is formed to a shape slightly larger than the shape of the metal fastener 1. Also, in the entrance portion hi of the hole h, the portion corresponding to the total shearing surface range of the left and right leg portion bodies 31 is provided as an inclined portion "provided with an inclined face for forming only a shearing surface" (hereinafter, simply referred to as an "inclined portion"). Further, the depth of the inclined face of the entrance portion hi is set to, for example, 0.20 mm to 0.30 mm. This value is a value obtained by rounding off the third digit after the decimal point with respect to unit mm. On the other hand, for the portion of the entrance portion hi of the hole h on which the inclined portion is not formed, only a chamfering process with a radius of 0.01 mm to 1.0 mm (this value is a value obtained by rounding off the third digit after the decimal point with respect to unit mm) or a chamfering process smaller than this is applied, and a curved face smoothly continuously formed in a shape bulging in a circular arc shape is formed by this chamfering process. Further, the portion of the entrance portion hi of the hole h on which the inclined portion is not formed is formed as a face parallel to the depth direction on the inner side with respect to the curved face to which this chamfering is applied.

[0053] In Figure 6 , Figure 7In the embodiment, in order to make the description easy to understand, an example in which the entire inclined portion is taken as the inclined surface is described, but in fact, the entire inclined portion does not necessarily have to be taken as the inclined surface, and in addition to the inclined surface, a curved surface that is smoothly continuous in a shape bulging in a circular arc shape with respect to the inclined surface is preferably provided by chamfer processing. For example, substantially the entire surface of the depth direction of the inlet portion h1 can be taken as the inclined surface, and the corner portion between the inlet portion h1 and the inside portion h2 can be taken as a curved surface that is smoothly continuous in a shape bulging in a circular arc shape with respect to the inclined surface (for example, the curved surface is a curved surface formed by chamfer processing with a radius of 0.01 mm to 1.0 mm, in which the value is a value obtained by rounding off the third digit after the decimal point to the nearest whole number with respect to 1 mm), and in addition, the corner portion between the inlet portion h1 and the upper surface of the female die 12 can also be taken as a curved surface that is smoothly continuous in a shape bulging in a circular arc shape with respect to the inclined surface.

[0054] The entire inclined surface is linearly inclined with respect to the depth direction of the hole h. In addition, the inclined state is a state in which the width of the hole h narrows toward the inside of the hole h. That is, in the state in which the width of the hole narrows toward the inside of the hole h, the inclined surface is inclined with respect to the depth direction of the hole h. In addition, the inclined surface is inclined with respect to the depth direction of the hole h at an angle θ that satisfies the following relationship 1. Note that the depth direction refers to the linear direction of the reciprocating movement of the male die 11. The relationship 1 is 0° < θ ≦ 30°. Note that preferably, the relationship 1 is in the range of 10° ≦ θ ≦ 28°, and more preferably, the relationship 1 is in the range of 15° ≦ θ ≦ 25° (10°, 20°, 25°, 28°, 30° are values obtained by rounding off the first digit after the decimal point to the nearest whole number).

[0055] Here, the meaning of the inclined surface is further described. In the second stamping processing described above, the metal zipper tooth 1 is punched out from the metal plate 7 in a stripping manner, and the portion that is stripped is considered to be a fracture surface. In the present application, by providing the inclined surface, the timing at which the metal zipper tooth 1 is stripped from the metal plate 7 is delayed, and the stripping can be performed over the upper surface in the thickness direction of the metal zipper tooth 1. Thus, in the range in the thickness direction, no trace of the stripping of the metal zipper tooth 1 from the metal plate 7 is left, that is, a surface without a fracture surface can be formed. On the other hand, as described in the prior example, in the case where the inlet portion h1 of the hole h of the female die 12 is subjected to chamfer processing with a radius of 0.01 mm to 1.0 mm, and the inside of the hole h with respect to the portion subjected to the chamfer processing is formed to be parallel to the depth direction, even if most of the surface can be made into a shearing surface, in the range in the thickness direction of the metal zipper tooth 1, a trace of the stripping of the metal zipper tooth 1 from the metal plate 7 is left. Therefore, the inclined surface in the present application needs a certain length so that no trace of the stripping of the metal zipper tooth 1 from the metal plate 7 is left in the range in the thickness direction of the metal zipper tooth 1.

[0056] Further, the gap T in the gap between the punch 11 and the die 12 with respect to the inclined portion at the inner side portion h2 of the hole h satisfies the following relational expression 2. Relational expression 2: 0.1 μm < T < 10 μm.

[0057] Note that, it is preferable to apply barrel polishing or chemical polishing to the metal zipper tape 1 after the second press working process. The metal zipper tape 1 of the first embodiment described above is the zipper tape after the finishing process.

[0058] Since the metal zipper tape 1 of the first embodiment manufactured by the manufacturing method of the metal zipper tape 1 for a zipper of the first embodiment described above does not have the fracture surface 5 in the total shearing surface range of the outer side surface of the left and right leg portion main bodies 31 or the outer side surface of the engagement head portion 2, the appearance of the metal zipper tape 1 is improved compared to the metal zipper tape 1 having the fracture surface 5 in the outer side surface. The larger the total shearing surface range, the more the appearance of the metal zipper tape 1 is improved.

[0059] Further, in the manufacturing method of the metal zipper tape 1 for a zipper of the first embodiment described above, the inclined portion having the inclined surface is formed at the entrance portion hi of the hole h of the die 12, and the inclined surface is inclined in a state where the width of the hole h narrows toward the inner side of the hole, so that in the blanking press working, the outer side surface of the left and right leg portion main bodies 31 is formed in a state of being pressed by the inclined surface during the passage through the inclined surface, and as a result, the total shearing surface range of the outer side surface of the left and right leg portion main bodies 31 is formed only with the shearing surface 4 without a fracture (without formation of a peeling trace) in the thickness range of the metal zipper tape compared to the manufacturing method using the press working which only punches out the metal zipper tape from the metal plate. Further, the inclined surface satisfies the relational expression 1, and on this basis, the gap T in the gap between the punch 11 and the die 12 with respect to the inclined surface at the inner side portion h2 of the hole h is made to satisfy the relational expression 2, so that the surface roughness of the shearing surface 4 is as desired.

[0060] The present application is not limited to the above-described embodiments, and can be appropriately changed within the scope of the gist thereof.

[0061] Explanation of symbols:

[0062] 1 metal zipper tape

[0063] 2 engagement head portion

[0064] 21 head portion main body

[0065] 22 engagement protrusion

[0066] 23 engagement recess

[0067] 25 joint portion

[0068] 26 flat plate portion

[0069] 3 leg portion

[0070] 31 leg portion main body

[0071] 32 clamping portion

[0072] 32a clamping surface

[0073] 4 shear surface

[0074] 5 fracture surface

[0075] 7 metal plate

[0076] 9 band portion

[0077] 9a core portion

[0078] 9b band portion main body portion

[0079] 11 punch

[0080] 12 die

[0081] C1, C2 corner portion (curved surface)

[0082] h hole

[0083] h1 entry portion

[0084] h2 inner side portion

[0085] L0 virtual line (lower limit boundary line)

[0086] L1 virtual line (first boundary line)

[0087] L2 virtual line (second boundary line)

[0088] L3 virtual line (third boundary line)

[0089] L4 virtual line (upper limit boundary line)

[0090] T gap

[0091] S1, S2, S3, S4, S5, S6, S7, S8 range

[0092] θ angle

Claims

1. A metal zipper tooth (1) for zippers, characterized in that, The zipper has metal zipper teeth (1) with engaging heads (2) and left and right feet (3). The left and right feet (3) include: left and right foot bodies (31) extending from the engaging head (2) into two branches; and left and right clamping portions (32) extending from the front ends of the left and right foot bodies (31) in a direction toward each other. The left and right foot bodies (31) have a portion on their outer side surface that has only a shear surface (4) and no fracture surface (5) within a fixed width range, the fixed width range referring to the entire outer side surface (S7, S8) of the left and right foot bodies (31).

2. The metal zipper teeth (1) for zippers according to claim 1, characterized in that, The fixed width range refers to the range (S1, S2) corresponding to the core (91) of the strap (9) held by the left and right foot bodies (31).

3. The metal zipper tooth (1) for zippers according to claim 1 or 2, characterized in that, The outer surface of the meshing head (2) also has a portion that has only a shearing surface (4) but no fracture surface (5).

4. A method for manufacturing a metal zipper tooth (1) for zippers, characterized in that, It possesses: The metal sheet (7) is plastically deformed in its thickness direction by stamping to form the engaging protrusion (22) and engaging recess (23) of the engaging head (2) of the metal zipper tooth (1); and The stamping process is used to cut out the metal zipper teeth (1) as the finished product from the metal plate (7) after the forming process. In the stamping process for blanking, the shape of the engaging head (2) of the metal zipper tooth (1) is formed, and the shape of the left and right feet (3) is formed. The left and right feet (3) include: left and right foot bodies (31) that extend from the engaging head (2) into two branches; and left and right clamping portions (32) that extend from the front ends of the left and right foot bodies (31) in a direction that approaches each other. The die (12) used in the stamping process has an inclined portion, which has an inclined surface within a fixed width range in the inlet (h1) of the hole (h) of the die (12) and in the portion corresponding to the outer surfaces of the left and right foot bodies (31). The inclined surface is linearly inclined relative to the depth direction of the hole (h) while facing inwards towards the hole (h), thus narrowing the width of the hole (h), and is inclined at an angle θ satisfying the following relationship 1. Relationship 1: 0°<θ≦30°.

5. The method for manufacturing the metal zipper tooth (1) for zippers according to claim 4, characterized in that, The fixed width range refers to the range corresponding to the core (91) of the strap (9) held by the left and right foot bodies (31).

6. The method for manufacturing the metal zipper tooth (1) for zippers according to claim 4, characterized in that, The fixed width range refers to the entire outer side of the left and right foot body (31).

7. The method for manufacturing the metal zipper teeth (1) for zippers according to any one of claims 4 to 6, characterized in that, The die (12) used in the stamping process is also provided with an inclined portion at the entrance (h1) of the hole (h) of the die (12) and at the portion corresponding to the outer side of the meshing head (2).

8. The method for manufacturing the metal zipper tooth (1) for zippers according to any one of claims 4 to 6, characterized in that, The inclined surface is inclined at an angle θ relative to the depth direction of the hole (h) to satisfy the following relationship 1. Relationship 1: 10°≦θ≦28°.

Images