Slide fastener
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-02-10
- Publication Date
- 2026-08-13
Smart Images
Figure JP2025004435_13082026_PF_FP_ABST
Abstract
Description
Slide fastener
[0001] The present invention relates to a slide fastener.
[0002] Conventionally, there are slide fasteners with improved flexibility by devising the shape of elements. For example, in the slide fastener disclosed in Patent Document 1, elements form pairs (hereinafter referred to as element pairs) between a pair of left and right fastener strings, and adjacent element pairs in the front and rear contact each other without meshing. Thereby, each element pair has mobility and the flexibility of the slide fastener is improved.
[0003] U.S. Patent No. 8,448,304
[0004] However, in the slide fastener described in Patent Document 1, when bending occurs in the longitudinal direction of the slide fastener, there is a possibility of cracks occurring between the pair of fastener strings, and the flexibility of the slide fastener cannot be said to be sufficient. The present invention aims to provide a slide fastener with improved flexibility.
[0005] [1] A slide fastener according to one aspect of the present invention comprises a first fastener stringer and a second fastener stringer which are combined with each other, the first fastener stringer and the second fastener stringer each comprising a fastener tape and a plurality of elements arranged in the longitudinal direction of the fastener tape, the elements comprising an element body attached to the side edge of the fastener tape and an engaging portion which protrudes from the element body to one side in the width direction perpendicular to the longitudinal direction and engages with the other element in the combination partner, Each engaging portion comprises a convex portion projecting to one side in the longitudinal direction, a recess opening between the convex portion and the element body, and an engaging side facing the other side in the longitudinal direction. The engaging portions of the element of the first fastener stringer and the engaging portions of the element of the second fastener stringer are arranged alternately in opposite directions in the longitudinal direction such that the convex portion fits into the recess and the engaging side faces each other. The engaging side has a pair of inclined surfaces that are inclined with respect to the thickness direction, which is perpendicular to the longitudinal direction and the width direction, and that form a taper.
[0006] [2] In the above [1], the element body portion has a pair of first body sides that face the same direction as the engaging side in the length direction and are arranged on both sides in the thickness direction with respect to the fastener tape, and it is preferable that the inclination angle of the inclined surface with respect to the thickness direction is greater than the inclination angle of the first body sides with respect to the thickness direction.
[0007] [3] In the above [1] or [2], the element body portion has a pair of second body sides that face the same direction as the protruding direction of the convex portion in the length direction and are arranged on both sides in the thickness direction with respect to the fastener tape, and it is preferable that the inclination angle of the inclined surface with respect to the thickness direction is greater than the inclination angle of the second body sides with respect to the thickness direction.
[0008] [4] In any of the above [1] to [3], it is preferable that the engaging side surface extends along one direction inclined with respect to the width direction so as to face the opposite direction to the protruding direction of the engaging portion.
[0009] [5] In any of the above [1] to [4], it is preferable that the engaging surface of the element is in slidable contact with the engaging surface of the other element.
[0010] [6] In any of the above [1] to [5], it is preferable that the element further comprises a fin portion extending from the element body, the engaging portion further comprises an engaging groove for accommodating the fin portion of the other element that is the pairing partner, and when the element is viewed along the thickness direction, the engaging groove extends along the length direction, and the tip of the fin portion is formed in an acute angle.
[0011] [7] In any of the above [1] to [6], the fastener stringer further comprises a butterfly bar attached to the first fastener stringer and a box bar attached to the second fastener stringer and facing the butterfly bar, wherein the butterfly bar comprises a butterfly bar body portion that holds the side edge portion of the fastener tape and a butterfly bar projection portion that protrudes from the butterfly bar body portion toward the box bar and fits onto the box bar, wherein the butterfly bar projection portion has a butterfly bar projection side surface that faces toward the element side of the first fastener stringer and is inclined with respect to the width direction so as to face toward the opposite side of the box bar, and preferably the butterfly bar projection side surface faces toward the engaging side surface of the element adjacent to the box bar in the second fastener stringer.
[0012] [8] In the above [7], it is preferable that the side surface of the butterfly bar projection has a pair of butterfly bar inclined surfaces that are inclined with respect to the thickness direction and form a taper.
[0013] [9] In the above [8], the butterfly bar body is arranged on both sides in the thickness direction with respect to the side edge of the fastener tape and has a pair of butterfly bar body sides facing the element side of the first fastener stringer, and preferably the inclination angle of the butterfly bar inclined surface with respect to the thickness direction is greater than the inclination angle of the butterfly bar body sides with respect to the thickness direction.
[0014]
[10] In the above [7] to [9], it is preferable that the element has a symmetrical shape in the thickness direction, and the butterfly bar projection has an asymmetrical shape in the thickness direction.
[0015]
[11] In any of the above [7] to
[10] , it is preferable that the position of the protruding tip of the butterfly bar projection is located on the side edge side of the fastener tape of the first fastener stringer, rather than the position of the protruding tip of the engaging portion of the element of the first fastener stringer.
[0016] A front view showing a slide fastener according to one embodiment of the present invention. A side view showing the slider of the above embodiment. A front view showing the element of the above embodiment. A perspective view showing the element of the above embodiment. A perspective view showing the element of the above embodiment from a different direction than that shown in Figure 4. A front view showing an element pair in the slide fastener of the above embodiment. A cross-sectional view of the element corresponding to the A-A cutting line in Figure 6. A cross-sectional view of the element corresponding to the B-B cutting line in Figure 6. A front view showing the opening and element pair in the slide fastener of the above embodiment. A front view showing the opening in the slide fastener of the above embodiment in a separated state. A perspective view showing the butterfly rod of the above embodiment. A perspective view showing the box rod and box body of the above embodiment. A partial perspective view showing a part of the slide fastener when the slide fastener of the above embodiment is bent in the longitudinal direction. A diagram showing the arrangement of elements when the slide fastener of the above embodiment is bent in the longitudinal direction, and a cross-sectional view corresponding to Figure 7. A diagram showing the arrangement of elements when the slide fastener of the above embodiment is bent in the longitudinal direction, and a cross-sectional view corresponding to Figure 8. A diagram illustrating a slide core for injection molding the elements of the above embodiment. A diagram explaining the case of separating the slide fastener of the above embodiment. Front view showing an element pair relating to a modified version. Front view showing an element pair relating to another modified version.
[0017] One embodiment of the present invention will be described with reference to the drawings. As shown in Figure 1, the slide fastener 1 of this embodiment comprises a first fastener stringer 10A and a second fastener stringer 10B (hereinafter sometimes referred to as fastener stringers 10A and 10B) that are combined with each other, a slider 3 that is movable relative to the fastener stringers 10A and 10B, an upper stopper 4 provided at one end of each of the fastener stringers 10A and 10B, and an opener 5 provided at the other end of the fastener stringers 10A and 10B.
[0018] In the following explanation, for convenience, we will use the mutually orthogonal X, Y, and Z directions. In this embodiment, the X direction is the length direction of the slide fastener 1 and is equal to the direction of movement of the slider 3 relative to the fastener stringers 10A and 10B. The Y direction is the width direction of the slide fastener 1 and is equal to the parallel direction of the fastener stringers 10A and 10B. The Z direction is the front and back direction of the slide fastener 1 (or the thickness direction of the slide fastener 1). One side of the X direction (the direction in which the slider 3 moves toward the upper stopper 4) will be referred to as the +X direction, and the other side of the X direction (the direction in which the slider 3 moves toward the opener 5) will be referred to as the -X direction.
[0019] (Overall configuration of slide fastener 1) The fastener stringers 10A and 10B of this embodiment each have a fastener tape 11 and a plurality of elements 2A (or a plurality of elements 2B) attached to the side edge 110 of the fastener tape 11. The fastener tape 11 is a strip that extends along the X direction and has thickness in the Z direction. The fastener tape 11 may include a core cord that extends along the X direction as the side edge 110 of the fastener tape 11.
[0020] Multiple elements 2A and 2B in each fastener stringer 10A and 10B are arranged at a predetermined pitch along the X direction, forming an element row 12 arranged along the X direction. The elements 2A of the first fastener stringer 10A and the elements 2B of the second fastener stringer 10B are configured to be engageable with each other, as will be described later.
[0021] The slider 3 comprises a slider body 31 that is movable in the X direction relative to the fastener stringers 10A and 10B, and a pull handle 32 connected to the slider body 31. As shown in Figure 2, the slider body 31 comprises an upper wing plate 311 and a lower wing plate 312 facing each other, a guide column 313 connecting the upper wing plate 311 and the lower wing plate 312 to each other, a pair of flanges 314A and 314B provided at both ends of the upper wing plate 311 in the Y direction, and a pair of flanges 315A and 315B provided at both ends of the lower wing plate 312 in the Y direction.
[0022] The slider fuselage 31 has a space formed between the upper wing plate 311 and the lower wing plate 312. This space is divided by a guide post 313 into a first insertion passage C1 for the element row 12 of the first fastener stringer 10A to be inserted through, and a second insertion passage C2 for the element row 12 of the second fastener stringer 10B to be inserted through. The first insertion passage C1 and the second insertion passage C2 merge on the -X side of the guide post 313.
[0023] As shown in Figure 1, the upper stopper 4 is attached to the +X side end of each side edge 110 of the fastener stringers 10A and 10B and is positioned adjacent to the element row 12. The upper stopper 4 prevents the slider 3 from falling off the fastener stringers 10A and 10B.
[0024] The opening tool 5 comprises a butterfly pin 6 attached to the -X side end of the side edge 110 of the first fastener stringer 10A, and a box rod 7 and a box body 8 attached to the -X side end of the side edge 110 of the second fastener stringer 10B. The butterfly pin 6 is configured to be insertable and removable from the box body 8. When the butterfly pin 6 is inserted into the box body 8, the butterfly pin 6 and the box rod 7 face each other in the Y direction and interlock with each other as described later.
[0025] In this embodiment, elements 2A, 2B, the upper stopper 4, and the opening 5 can be injection molded onto the side edge 110 of the fastener tape 11 using any resin material. However, the materials of elements 2A, 2B, the upper stopper 4, and the opening 5 are not particularly limited and may be metal materials.
[0026] In this embodiment, when the hinge pin 6 is inserted into the box body 8 and the slider 3 moves in the +X direction, the elements 2A and 2B of the fastener stringers 10A and 10B interlock with each other by the slider 3, and the slide fastener 1 is closed. On the other hand, when the slider 3 moves in the -X direction, the interlocking of the elements 2A and 2B of the fastener stringers 10A and 10B is released by the slider 3, and the slide fastener 1 is opened. Then, when the hinge pin 6 is removed from the box body 8, the fastener stringers 10A and 10B separate from each other.
[0027] (Element Configuration) Next, the configuration of each element 2A, 2B of the fastener stringers 10A, 10B will be described with reference to Figures 3 to 8. Figures 3 to 5 show the element 2B individually, and Figure 6 is an enlarged view of a pair of elements 2A, 2B (element pair 20) that interlock with each other between the fastener stringers 10A, 10B. Figure 7 is a cross-sectional view corresponding to the line A-A in Figure 6, and the fastener tape 11 is not shown. Figure 8 is a cross-sectional view corresponding to the line B-B in Figure 6.
[0028] Furthermore, between the first fastener stringer 10A and the second fastener stringer 10B, the elements 2A and 2B are positioned in a configuration where they are rotated 180° relative to each other on the XY plane. In other words, element 2A of the first fastener stringer 10A has a posture where element 2B of the second fastener stringer 10B is inverted in the X and Y directions, respectively.
[0029] The elements 2A and 2B of the first fastener stringer 10A and the second fastener stringer 10B have similar configurations to each other, except for their arrangement in the slide fastener 1. In the following, we will mainly use the element 2B of the second fastener stringer 10B for explanation, and will use the X, Y, and Z directions based on the arrangement of the element 2B of the second fastener stringer 10B in the slide fastener 1. The following explanation of the element 2B of the second fastener stringer 10B can be applied to the element 2A of the first fastener stringer 10A by reversing the positive and negative signs of the X and Y directions.
[0030] As shown in Figures 3 to 5, element 2B comprises an element body portion 21, an engaging portion 22 protruding from the element body portion 21 to one side in the Y direction (hereinafter, the +Y direction), and a fin portion 23 adjacent to the engaging portion 22 in the X direction and extending from the element body portion 21. The element body portion 21 and the engaging portion 22 have equal thickness in the Z direction. On the other hand, the fin portion 23 has a thickness smaller than the respective thicknesses of the element body portion 21 and the engaging portion 22, and is provided in the center of the element body portion 21 in the Z direction.
[0031] The element body portion 21 has a roughly rectangular parallelepiped shape. A tape groove 21S is formed in this element body portion 21, on which the side edge portion 110 of the fastener tape 11 is placed. The tape groove 21S penetrates the center portion of the element body portion 21 in the Z direction in the X direction and opens to the other side in the Y direction (hereinafter, the -Y direction).
[0032] Furthermore, the element body portion 21 has a pair of first body side surfaces 211A, 211B that face the -X direction and are arranged on both sides in the Z direction with respect to the tape groove 21S, and a pair of second body side surfaces 212A, 212B that face the +X direction and are arranged on both sides in the Z direction with respect to the tape groove 21S.
[0033] The first main body sides 211A and 211B are inclined with respect to the Z direction so as to form a taper centered on a virtual line passing through the center of element 2B in the Z direction (for example, virtual line L in Figure 7). Similarly, the second main body sides 212A and 212B are inclined with respect to the Z direction so as to form a taper centered on a virtual line passing through the center of element 2B in the Z direction (for example, virtual line L in Figure 7).
[0034] The engaging portion 22 has a roughly triangular prism shape. Specifically, the engaging portion 22 has a neck portion 221 that extends from the element body portion 21 in the +Y direction and is constricted in the X direction, and a head portion 222 that extends from the neck portion 221 in the +Y direction and is wider in the X direction than the neck portion 221. The engaging portion 22 has an engaging groove 22S that penetrates the center of the head portion 222 in the Z direction in the X direction and opens in the +Y direction.
[0035] Furthermore, the engaging portion 22 has a recess 223 formed on the neck portion 221 and opening in the +X direction, and a protrusion 224 formed on the head portion 222 and projecting in the +X direction. That is, the engaging portion 22 has a concave and convex shape on the +X side for interlocking with the engaging portions 22 of other elements 2A. The recess 223 opens between the element body portion 21 and the protrusion 224, and the recess 223 and the protrusion 224 are formed by a curved surface 225 that extends along the Z direction and curves continuously along the Y direction.
[0036] Furthermore, the engaging portion 22 has an engaging side surface 227 formed so as to face the -X direction from the neck portion 221 to the head portion 222. This engaging side surface 227 extends along one direction that is inclined with respect to the Y direction so as to face the -Y direction. In other words, the engaging side surface 227 is inclined with respect to the Y direction so as it moves toward the +Y direction, it moves toward the -X direction. When the element 2B is viewed along the Z direction, the engaging side surface 227, together with the first body sides 211A and 211B of the element body portion 21, forms an obtuse-angled concave shape that opens toward the -X direction.
[0037] The engaging side surface 227 has a pair of inclined surfaces 227A and 227B that are inclined with respect to the Z direction and form a taper. That is, the inclined surfaces 227A and 227B are inclined with respect to the Z direction so as to form a taper together with respect to a virtual line (for example, virtual line L in Figure 8) passing through the center of the element 2B in the Z direction. In particular, in the engaging side surface 227 of this embodiment, the pair of inclined surfaces 227A and 227B form an obtuse-angled corner between them.
[0038] Here, the inclination angles θ3 of the inclined surfaces 227A and 227B with respect to the Z direction (see Figure 8) are greater than the inclination angles θ1 of the first main body sides 211A and 211B with respect to the Z direction (see Figure 7). Similarly, the inclination angles θ3 of the inclined surfaces 227A and 227B with respect to the Z direction (see Figure 8) are greater than the inclination angles θ2 of the second main body sides 212A and 212B with respect to the Z direction (see Figure 7). For example, the inclination angles θ1 of the first main body sides 211A and 211B and the inclination angles θ2 of the second main body sides 212A and 212B are 5° each, while the inclination angles θ3 of the inclined surfaces 227A and 227B are between 10° and 15°.
[0039] The fin portion 23 extends from the recess 223 of the element body portion 21 and the engaging portion 22, and is positioned on the +X side relative to the engaging portion 22. When the element 2B is viewed along the Z direction, the fin portion 23 has a substantially triangular shape. Specifically, the fin portion 23 has a first edge portion 231 facing the +Y direction, a second edge portion 232 facing the +X direction, and an acute-angled tip portion 233 formed between the first edge portion 231 and the second edge portion 232. The first edge portion 231 extends along a direction inclined with respect to the extending direction of the engaging groove 22S (the X direction in this embodiment), and the second edge portion 232 extends along the Y direction. The acute angle of the tip portion 233 has an R shape.
[0040] (Configuration of the fastener stringer) Element 2A of the first fastener stringer 10A and element 2B of the second fastener stringer 10B are arranged to be combined with each other. The arrangement of elements 2A and 2B in the slide fastener 1 will be described below.
[0041] As shown in Figure 6, in the first fastener stringer 10A, the multiple elements 2A are arranged at a predetermined pitch. Specifically, the first body side surface 211A (or 211B) of an element 2A and the second body side surface 212A (or 212B) of another adjacent element 2A in the X direction face each other with a predetermined gap in between. Similarly, in the second fastener stringer 10B, the multiple elements 2B are arranged at a predetermined pitch. Specifically, the first body side surfaces 211A, 211B of elements 2B and the second body side surfaces 212A, 212B of other adjacent elements 2B in the X direction face each other with a predetermined gap in between.
[0042] As described above, the element 2A of the first fastener stringer 10A and the element 2B of the second fastener stringer 10B are arranged in a configuration where they are rotated 180° relative to each other on the XY plane. The engaging portions 22 of elements 2A and 2B are arranged alternately in the X direction such that the convex portion 224 fits into the concave portion 223 and the engaging sides 227 face each other. Specifically, the convex portion 224 of the engaging portion 22 of element 2A fits into the concave portion 223 of the engaging portion 22 of element 2B, and the convex portion 224 of the engaging portion 22 of element 2B fits into the concave portion 223 of the engaging portion 22 of element 2A. In addition, the fin portion 23 of element 2A fits into the engaging groove 22S of element 2B, and the fin portion 23 of element 2B fits into the engaging groove 22S of element 2A. This constitutes an element pair 20 in which elements 2A and 2B are interlocked. In element pair 20, the movement of each element 2A, 2B in both the Y direction and the Z direction is restricted.
[0043] In the slide fastener 1, multiple pairs of elements 20 are arranged along the X direction, and between adjacent pairs of elements 20, the engaging side surfaces 227 of element 2A of the first fastener stringer 10A and the engaging side surfaces 227 of element 2B of the second fastener stringer 10B face each other and are in partial contact in the X and Y directions, respectively. In this embodiment, only the engaging side surfaces 227 are in contact between adjacent pairs of elements 20, and each pair of elements 20 is movable by the sliding of the engaging side surfaces 227.
[0044] A tapered gap in the Z direction is formed between the pairs of elements 20. Specifically, in each fastener stringer 10A, 10B, as shown in Figure 7, a tapered gap G1 is formed between the first body sides 211A, 211B and the second body sides 212A, 212B of elements 2A, 2B. In addition, between the fastener stringers 10A, 10B, as shown in Figure 8, a tapered gap G2 is formed between the inclined surfaces 227A, 227B of element 2A and the inclined surfaces 227A, 227B of element 2B.
[0045] Here, the opening angle α2 (see FIG. 8) of the tapered gap G2 formed between the inclined surfaces 227A (or between the inclined surfaces 227B) is larger than the opening angle α1 (see FIG. 7) of the tapered gap G1 formed between the first main body side surface 211A and the second main body side surface 212A (or between the first main body side surface 211B and the second main body side surface 212B).
[0046] (Configuration of the opener) Next, referring to FIGS. 9 to 12, the configuration of the opener 5 of the present embodiment will be described. FIGS. 9 and 10 are enlarged views showing the opener 5 and the adjacent element pair 20 in the slide fastener 1. Note that FIG. 9 shows the case where the slide fastener 1 is in the closed state, and FIG. 10 shows the case where the slide fastener 1 is in the open state. FIG. 11 is a perspective view showing the wing bar 6, and FIG. 12 is a perspective view showing the box bar 7 and the box body 8.
[0047] Hereinafter, with reference to the arrangement of the opener 5 in the slide fastener 1, the X direction, Y direction, and Z direction are used. Also, hereinafter, basically, the arrangement of the opener 5 when the slide fastener 1 is in the closed state will be described.
[0048] As described above, the opener 5 includes a wing bar 6 attached to the -X side end portion of the side edge portion 110 of the first fastener stringer 10A, and a box bar 7 and a box body 8 attached to the -X side end portion of the side edge portion 110 of the second fastener stringer 10B.
[0049] The wing bar 6 includes a wing bar main body portion 61 that holds the side edge portion 110 of the fastener tape 11, and a wing bar protrusion portion 62 that protrudes from the wing bar main body portion 61 toward the box bar 7 side (that is, in the -Y direction) and fits into the box bar 7.
[0050] The wing bar main body portion 61 is a rod body inserted into the box body 8. As shown in FIG. 11, the wing bar main body portion 61 has a predetermined length in the X direction and substantially constant thicknesses in the Y direction and the Z direction respectively. The wing bar main body portion 61 has a tape groove 61S in which the side edge portion 110 of the fastener tape 11 is arranged. The tape groove 61S penetrates the central portion of the wing bar main body portion 61 in the Z direction in the X direction and opens in the +Y direction.
[0051] Furthermore, the butterfly bar body portion 61 has a pair of butterfly bar body sides 611A and 611B that face the +X direction and are positioned on both sides in the Z direction relative to the fastener tape 11 (i.e., tape groove 61S). The butterfly bar body sides 611A and 611B are inclined with respect to the Z direction so as to form a taper together with respect to an imaginary line passing through the center of the butterfly bar 6 in the Z direction.
[0052] The butterfly bar projection 62 has an engagement groove 62S that penetrates the center of the butterfly bar projection 62 in the Z direction in the X direction and opens in the -Y direction. The butterfly bar projection 62 also has a recess 621 that opens in the -X direction and a protrusion 622 that is located on the -Y side of the recess 621 and protrudes in the -X direction.
[0053] In this embodiment, the butterfly bar projection 62 has an asymmetric shape in the Z direction. Specifically, the butterfly bar projection 62 includes a pair of divided projections 62A and 62B that are divided in the Z direction by the engagement groove 62S. Of the pair of divided projections 62A and 62B, the divided projection 62B on the -Z side has the aforementioned recess 621 and convex portion 622 formed thereon, but the divided projection 62A on the +Z side does not have the aforementioned recess 621 and convex portion 622 formed thereon, and has a shape as if the recess 621 is filled in.
[0054] Furthermore, the butterfly bar projection 62 has a butterfly bar projection side surface 623 facing the element 2A side (i.e., the +X direction) of the first fastener stringer 10A. The butterfly bar projection side surface 623 is inclined with respect to the Y direction so as to face the +X direction and the opposite side from the box bar 7 side (i.e., the +Y direction). In other words, the butterfly bar projection side surface 623 is inclined with respect to the Y direction so as it moves toward the protruding direction of the butterfly bar projection 62 (i.e., the -Y direction), it moves toward the +X direction. When the butterfly bar 6 is viewed along the Z direction, the butterfly bar projection side surface 623, together with the butterfly bar body sides 611A and 611B of the butterfly bar body portion 61, forms an obtuse-angled concave shape that opens in the +X direction.
[0055] The side surface 623 of the butterfly bar projection has a pair of butterfly bar inclined surfaces 623A and 623B that taper to be inclined with respect to the Z direction, similar to the engaging side surfaces 227 of elements 2A and 2B. That is, the butterfly bar inclined surfaces 623A and 623B are inclined with respect to the Z direction so as to form a taper together with respect to a virtual line passing through the center of the butterfly bar 6 in the Z direction. In particular, in the side surface 623 of the butterfly bar projection of this embodiment, the butterfly bar inclined surfaces 623A and 623B form an obtuse-angled corner between them.
[0056] Here, the inclination angles of the butterfly bar body sides 611A and 611B with respect to the Z direction are equal to the inclination angles θ1 of the first body sides 211A and 211B of elements 2A and 2B. Also, the inclination angles of the butterfly bar inclined surfaces 623A and 623B with respect to the Z direction are equal to the respective inclination angles θ3 of the inclined surfaces 227A and 227B with respect to the Z direction. Therefore, the inclination angles of the butterfly bar inclined surfaces 623A and 623B with respect to the Z direction (=θ3) are greater than the inclination angles of the butterfly bar body sides 611A and 611B with respect to the Z direction (=θ1).
[0057] The protruding length of the butterfly bar projection 62 is shorter than the protruding length of the engaging portion 22 of the element 2A of the first fastener stringer 10A. In other words, in the first fastener stringer 10A, the protruding tip position P1 of the butterfly bar projection 62 is located closer to the side edge 110 of the fastener tape 11 than the protruding tip position P2 of the engaging portion 22 of the element 2A (see Figure 9). There exists an arbitrary difference Δd in the Y direction between the protruding tip position P1 of the butterfly bar projection 62 and the protruding tip position P2 of the engaging portion 22 of the element 2A.
[0058] The box bar 7 comprises a box bar body portion 71 that holds the side edge portion 110 of the fastener tape 11, a box bar projection portion 72 that protrudes from the box bar body portion 71 toward the butterfly bar 6 (i.e., in the +Y direction), and a fin portion 73 that protrudes from the box bar body portion 71 in the +Y direction on the +X side of the engaging portion 22. The box bar body portion 71 and the box bar projection portion 72 have equal thickness to each other in the Z direction. On the other hand, the fin portion 73 has a thickness smaller than the respective thicknesses of the box bar body portion 71 and the box bar projection portion 72, and is provided in the center of the box bar body portion 71 in the Z direction.
[0059] As shown in Figure 12, the box bar body portion 71 has a predetermined length in the X direction and a substantially constant thickness in both the Y and Z directions. The box bar body portion 71 has a tape groove 71S in which the side edge portion 110 of the fastener tape 11 is arranged. The tape groove 71S penetrates the center of the box bar body portion 71 in the Z direction in the X direction and opens in the -Y direction.
[0060] Furthermore, the box bar body portion 71 has a pair of box bar body sides 711A and 711B that face the +X direction and are positioned on both sides in the Z direction relative to the fastener tape 11 (i.e., tape groove 71S). The box bar body sides 711A and 711B are inclined with respect to the Z direction so as to form a taper together with respect to an imaginary line passing through the center of the butterfly bar 6 in the Z direction.
[0061] Here, the inclination angles of the box bar body sides 711A and 711B with respect to the Z direction are equal to the inclination angles θ2 of the second body sides 212A and 212B of elements 2A and 2B. Therefore, the inclination angles of the butterfly bar inclined surfaces 623A and 623B with respect to the Z direction (=θ3) are greater than the inclination angles of the box bar body sides 711A and 711B with respect to the Z direction (=θ2).
[0062] The box bar projection 72 forms a recess 721 that opens in the +X direction and a convex portion 722 that is positioned on the +Y side of the recess 721 and protrudes in the +X direction. In this embodiment, the box bar projection 72 has an asymmetric shape in the Z direction on the box bar 7. Specifically, the box bar 7 has the box bar projection 72 in the region on the -Z side of the fin portion 73, but does not have the box bar projection 72 in the region on the +Z side of the fin portion 73, and instead has a notch 74.
[0063] The box body 8 has a rectangular parallelepiped shape. The box body 8 has a base portion 81 integrally molded to the -X side end of the box rod 7, and a box wall portion 82 that forms the housing space RS on the +Y side relative to the base portion 81. The specific shape of the box body 8 is the same as in the conventional design.
[0064] As shown in Figure 9, in the opening mechanism 5 described above, the butterfly rod 6 is inserted into the storage space RS of the box body 8 and fitted into the box rod 7. At this time, the protrusion 622 of the butterfly rod 6 fits into the recess 721 of the box rod 7, and the protrusion 722 of the box rod 7 fits into the recess 621 of the butterfly rod 6. In addition, the fin portion 73 of the box rod 7 fits into the engagement groove 62S of the butterfly rod 6. Furthermore, the divided projection 62A of the butterfly rod 6 is housed in the notch 74 of the box rod 7.
[0065] Furthermore, when the butterfly rod 6 is inserted into the box body 8, the opening tool 5 of this embodiment has an arrangement relationship with respect to elements 2A and 2B adjacent to the opening tool 5 that is similar to the arrangement relationship between the element pairs 20 described above. Specifically, the side surfaces 611A and 611B of the butterfly rod body have an arrangement relationship corresponding to the first side surfaces 211A and 211B of element 2A, and the side surfaces 611A and 611B of the butterfly rod body and the second side surfaces 212A and 212B of element 2A adjacent to the butterfly rod 6 in the X direction face each other with a predetermined gap in between. The side surfaces 711A and 711B of the box rod body have an arrangement relationship corresponding to the second side surfaces 212A and 212B of element 2B, and the side surfaces 711A and 711B of the box rod body and the first side surfaces 211A and 211B of element 2B adjacent to the box rod 7 in the X direction face each other with a predetermined gap in between. The butterfly bar projection side surface 623 is positioned opposite the engaging side surface 227 of element 2A, and the butterfly bar projection side surface 623 and the engaging side surface 227 of element 2B are positioned opposite each other. Furthermore, the butterfly bar projection side surface 623 partially contacts the engaging side surface 227 of element 2B in both the X and Y directions.
[0066] Furthermore, the opening angle of the tapered gap formed between the side surfaces 611A, 611B of the butterfly rod body 6 and the second side surfaces 212A, 212B of element 2A (or between the side surfaces 711A, 711B of the box rod body and the first side surfaces 211A, 211B of element 2B) is equal to the opening angle α1 (see Figure 7) of the tapered gap G1 formed between the first side surface 211A and the second side surface 212A of elements 2A, 2B (or between the first side surface 211B and the second side surface 212B). Similarly, the opening angle of the tapered gap formed between the side surface 623 of the butterfly rod projection and the engaging side surface 227 of element 2B is equal to the opening angle α2 (see Figure 8) of the tapered gap G2 formed between the inclined surfaces 227A of elements 2A, 2B (or between the inclined surfaces 227B of elements 2A, 2B). Therefore, the opening angle (=α2) of the tapered gap formed between the butterfly rod projection side surface 623 and the engaging side surface 227 of element 2B is greater than the opening angle (=α1) of the tapered gap formed between the butterfly rod body side surfaces 611A, 611B of the butterfly rod 6 and the second body side surfaces 212A, 212B of element 2A (or between the box rod body side surfaces 711A, 711B and the first body side surfaces 211A, 211B of element 2B).
[0067] (Effects of this embodiment) As described above, the slide fastener 1 according to this embodiment comprises a first fastener stringer 10A and a second fastener stringer 10B that are combined with each other, and each of the first fastener stringer 10A and the second fastener stringer 10B comprises a fastener tape 11 and a plurality of elements 2A, 2B arranged in the longitudinal direction (X direction) of the fastener tape 11, and elements 2A, 2B comprises an element body portion 21 attached to the side edge portion 110 of the fastener tape 11 and an engaging portion 22 that protrudes from the element body portion 21 to one side (+Y side or -Y side) in the width direction perpendicular to the longitudinal direction and engages with the other element 2A, 2B in the combined pair, and the engaging portion 22 comprises a convex portion 224 projecting to one side in the longitudinal direction (+X side or -X side), a recess 223 opening between the convex portion 224 and the element body portion 21, and an engaging side surface 227 facing the other side in the longitudinal direction (-X side or +X side). The engaging portion 22 of element 2A of the first fastener stringer 10A and the engaging portion 22 of element 2B of the second fastener stringer 10B are arranged alternately in opposite directions in the longitudinal direction (X direction) such that the convex portion 224 fits into the recess 223 and the engaging side surfaces 227 face each other. The engaging side surfaces 227 have a pair of inclined surfaces 227A and 227B that are inclined with respect to the thickness direction (Z direction) which is perpendicular to the longitudinal direction and width direction, respectively, and form a taper.
[0068] In this configuration, the element 2A of the first fastener stringer 10A and the element 2B of the second fastener stringer 10B form an element pair 20 by the interlocking of the concave and convex shapes of the engaging portion 22. Since the engaging sides 227 of the element pair 20 face each other with respect to other adjacent element pairs 20 in the X direction, movement of the element pairs 20 in the width direction is suppressed while allowing the element pairs 20 to move apart in the width direction. Furthermore, since the engaging sides 227 of each element 2A, 2B have inclined surfaces 227A, 227B that are inclined with respect to the Z direction, a tapered gap G2 in the Z direction is formed between the element pairs 20. Therefore, when bending occurs in the length direction of the slide fastener 1, interference between the element pairs 20 is suppressed, and as a result, cracking between the first fastener stringer 10A and the second fastener stringer 10B can be suppressed. Accordingly, according to this embodiment, the flexibility of the slide fastener 1 can be improved.
[0069] The element body portion 21 of this embodiment has a pair of first body side surfaces 211A and 211B that face the same orientation as the engaging side surface 227 in the longitudinal direction and are arranged on both sides (±Z sides) in the thickness direction relative to the fastener tape 11, and the inclination angle θ3 of the inclined surfaces 227A and 227B with respect to the thickness direction (Z direction) is greater than the inclination angle θ1 of the first body side surfaces 211A and 211B with respect to the thickness direction (Z direction). Furthermore, the element body portion 21 of this embodiment has a pair of second body side surfaces 212A and 212B that face the same orientation as the protruding direction of the convex portion 224 in the longitudinal direction and are arranged on both sides (±Z sides) in the thickness direction relative to the fastener tape 11, and the inclination angle θ3 of the inclined surfaces 227A and 227B with respect to the thickness direction (Z direction) is greater than the inclination angle θ2 of the second body side surfaces 212A and 212B with respect to the thickness direction (Z direction). In this configuration, the opening angle α2 of the tapered gap G2 between two inclined surfaces 227A (or two inclined surfaces 227B) in adjacent element pairs 20 in the X direction is larger than the opening angle α1 of the tapered gap G1 between the first main body side surface 211A and the second main body side surface 212A (or between the first main body side surface 211B and the second main body side surface 212B) in adjacent elements 2A and 2B in the X direction. This provides the following effects.
[0070] Here, Figures 13 to 15 illustrate the arrangement of elements 2A and 2B when bending occurs in the slide fastener 1 of this embodiment. Figures 13 to 15 show examples of the arrangement of elements 2A and 2B when bending occurs in the longitudinal direction of the slide fastener 1. Figure 14 shows a cross-sectional view corresponding to Figure 7, and Figure 15 shows a cross-sectional view corresponding to Figure 8.
[0071] When the slide fastener 1 is bent as shown in Figure 13, adjacent pairs of elements 20 in the X direction move apart from each other on one side in the Z direction (e.g., the -Z side) while moving closer to each other on the other side in the Z direction (e.g., the +Z side). At this time, as illustrated in Figure 14, the first main body side surface 211B of element 2B and the second main body side surface 212B of another adjacent element 2B in the X direction interfere with each other. As a result, the element body portions 21 of adjacent elements 2B in the X direction support each other, and a force is generated that counteracts the bending force of the slide fastener 1. Note that although element 2B is illustrated in Figure 14, a similar force counteracting the bending force of the slide fastener 1 is generated for element 2A as well.
[0072] Furthermore, if bending occurs in the slide fastener 1 as shown in Figure 13, the inclined surfaces 227B of one pair of elements 20 and the inclined surfaces 227B of other adjacent pairs of elements 20 in the X direction will be arranged in a substantially parallel relationship, as illustrated in Figure 15. At this time, since the element bodies 21 of elements 2A and 2B support each other, strong contact between the inclined surfaces 227B is suppressed.
[0073] Therefore, when the slide fastener 1 is bent, the force with which the engaging portions 22 press against each other between pairs of elements 20 is smaller than the force with which the element bodies 21 press against each other in the fastener stringers 10A and 10B. In other words, the force applied to the engaging portions 22 is suppressed, which prevents the engaging portions 22 from disengaging. As a result, cracking between the fastener stringers 10A and 10B is suppressed, and the flexibility of the slide fastener 1 can be further improved.
[0074] In this embodiment, the engaging side surface 227 extends along one direction inclined with respect to the width direction (X direction) so as to face the opposite direction from the protruding direction of the engaging portion 22. Furthermore, the engaging side surface 227 of element 2A in this embodiment slidably contacts the engaging side surface 227 of other elements 2B. With this configuration, the interference between the engaging side surfaces 227 of elements 2A and 2B suppresses cracking of the slide fastener 1 while improving its flexibility.
[0075] In this embodiment, elements 2A and 2B further include fin portions 23 extending from the element body portion 21, and the engaging portion 22 further has an engaging groove 22S that accommodates the fin portions 23 of the other element 2A or 2B that it combines with. When elements 2A and 2B are viewed along the thickness direction, the engaging groove 22S extends along the length direction (X direction), and the tip portion 233 of the fin portion 23 is formed in an acute angle. With this shape of the fin portion 23, the strength of the mold for injection molding elements 2A and 2B can be improved.
[0076] For example, Figure 16 is a schematic diagram showing a part of the mold for element 2B. In Figure 16, the shape of a typical fin portion in a conventional element is shown by a dotted line as a comparative example. The mold for forming element 2B in this embodiment includes a slide core 91 for forming an engagement groove 22S (see, for example, Figure 4) in the engagement portion 22, a fixed core 92 having a cavity corresponding to the -Z side shape of element 2B, and a movable core (not shown) having a cavity corresponding to the +Z side shape of element 2B. The slide core 91 has a side edge portion 911 arranged along the extension direction (X direction) of the engagement groove 22S. In this embodiment, since the fin portion 23 has an acute-angled tip portion 233, the dimensions around the fin portion 23 in the fixed core 92 or movable core can be made larger than in the conventional design. In particular, since the first edge 231 of the fin portion 23 extends along a direction inclined with respect to the extension direction of the side edge 911 of the slide core 91 (i.e., the extension direction of the engagement groove 22S), a large dimension in the Y direction of the fixed core 92 or movable core can be secured between the slide core 91 and the first edge 231 of the fin portion 23. This improves the strength of the mold for injection molding the element 2B.
[0077] The slide fastener 1 of this embodiment further comprises a butterfly bar 6 attached to a first fastener stringer 10A, and a box bar 7 attached to a second fastener stringer 10B and facing the butterfly bar 6. The butterfly bar 6 comprises a butterfly bar body portion 61 that holds the side edge portion 110 of the fastener tape 11, and a butterfly bar projection portion 62 that protrudes from the butterfly bar body portion 61 toward the box bar 7 and fits onto the box bar 7. The butterfly bar projection portion 62 has a butterfly bar projection side surface 623 that faces the element 2A side of the first fastener stringer 10A and is inclined with respect to the width direction (Y direction) so as to face the opposite side from the box bar 7. The butterfly bar projection side surface 623 faces the engaging side surface 227 of the element 2B adjacent to the box bar 7 on the second fastener stringer 10B. In this configuration, the butterfly bar projection side surface 623 of the butterfly bar projection portion 62 faces the engaging side surface 227 of element 2B, similar to the engaging side surface 227 of element 2A. This allows for the mobility of the opening mechanism 5 within the slide fastener 1 while suppressing movement that would cause the butterfly bar projection 62 and the element pair 20 to separate in the width direction. As a result, the flexibility of the slide fastener 1 can be further improved. Furthermore, since the opening mechanism 5 of this embodiment has a design that fits the element pair 20 described above, the aesthetic appearance of the slide fastener 1 can be improved.
[0078] The side surface 623 of the butterfly bar projection in this embodiment has a pair of butterfly bar inclined surfaces 623A and 623B that are inclined with respect to the thickness direction (Z direction) and form a taper. The butterfly bar body portion 61 of this embodiment is arranged on both sides (±Z sides) in the thickness direction with respect to the side edge portion 110 of the fastener tape 11 and has a pair of butterfly bar body side surfaces 611A and 611B that face the element 2A side of the first fastener stringer 10A, and the inclination angle of the butterfly bar inclined surfaces 623A and 623B with respect to the thickness direction (Z direction) is greater than the inclination angle of the butterfly bar body side surfaces 611A and 611B with respect to the thickness direction (Z direction). In this configuration, the opening angle of the tapered gap between the butterfly bar inclined surface 623A and the inclined surface 227A of element 2B (or between the butterfly bar inclined surface 623B and the inclined surface 227B) is larger than the opening angle of the tapered gap between the butterfly bar body side surface 611A and the second body side surface 212A of element 2A (or between the butterfly bar body side surface 611B and the second body side surface 212B of element 2A). Therefore, when bending occurs in the longitudinal direction of the slide fastener 1, the interference between the opener 5 and the element pair 20 is the same as the interference between the element pairs 20 themselves as described above. That is, strong pressure between the butterfly bar projection 62 and the engaging portion 22 of element 2B is suppressed, and as a result, cracking between the fastener stringers 10A and 10B is suppressed, and the flexibility of the slide fastener 1 can be further improved.
[0079] In this embodiment, elements 2A and 2B have a symmetrical shape in the thickness direction (Z direction), while the butterfly bar projection 62 has an asymmetrical shape in the thickness direction (Z direction). With this configuration, when the butterfly bar 6 is combined with the box bar 7, it is possible to prevent the butterfly bar projection 62 from improperly engaging with the engagement portion 22 of element 2B.
[0080] In this embodiment, the protruding tip position P1 of the butterfly bar projection 62 is located on the side edge 110 side (+Y side) of the fastener tape 11 of the first fastener stringer 10A, rather than the protruding tip position P2 of the engaging portion 22 of the element 2A of the first fastener stringer 10A. With this configuration, when separating the first fastener stringer 10A and the second fastener stringer 10B, it is possible to prevent unintended erroneous movement of the slider 3 by the butterfly bar 6 and prevent the elements 2A and 2B from improperly engaging.
[0081] For example, Figure 17 is a schematic diagram showing how the first fastener stringer 10A and the second fastener stringer 10B are separated. As shown in Figure 17, when the butterfly rod 6 is pulled out from the box body 8 and the slider 3, the element 2A and the butterfly rod projection 62 pass through the inside of the slider 3. At this time, if the butterfly rod projection 62 were to interfere with the guide column 313 of the slider 3, the slider 3 would unintentionally move in the +X direction, and elements 2A and 2B might become improperly engaged. On the other hand, in this embodiment, the protruding tip position P1 of the butterfly rod projection 62 is located on the -Y side than the protruding tip position P2 of element 2A. Therefore, when the butterfly rod 6 is pulled out from the box body 8 and the slider 3, interference between the butterfly rod projection 62 and the guide column 313 of the slider 3 is suppressed. This prevents elements 2A and 2B from becoming improperly engaged.
[0082] (Modifications) In the elements 2A and 2B of the above embodiment, the shape of the element body portion 21 may be modified. For example, Figures 18 and 19 are diagrams illustrating elements 2A and 2B according to modifications. As shown in Figure 18, the first body side surface 211A and the second body side surface 212A of the element body portion 21 may extend along the X direction. Alternatively, as shown in Figure 19, when the elements 2A and 2B are viewed along the Z direction, the first body side surface 211A and the second body side surface 212A of the element body portion 21 may extend along the engaging side surface 227 of the engaging portion 22. The first body side surface 211B and the second body side surface 212B, which are not shown in Figures 18 and 19, may also be modified in the same way.
[0083] Furthermore, in the element body portion 21 of the above embodiment, the inclination angles θ1 and θ2 of the first body side surfaces 211A and 211B and the second body side surfaces 212A and 212B with respect to the Z direction are not particularly limited. For example, the first body side surfaces 211A and 211B and the second body side surfaces 212A and 212B may extend along the Z direction. Alternatively, the inclination angles θ1 and θ2 of the first body side surfaces 211A and 211B and the second body side surfaces 212A and 212B with respect to the Z direction may be greater than the inclination angle θ1 of the inclined surfaces 227A and 227B with respect to the Z direction.
[0084] In the elements 2A and 2B of the above embodiment, the shape of the fin portion 23 may be modified, or the fin portion 23 may be omitted.
[0085] In the above embodiment, the opening tool 5 is exemplified as an opening tool 5 for right-hand insertion, but the present invention is not limited thereto. For example, in the above embodiment, by providing the pull tab 32 of the slider 3 on the -Z side, the front and back of the slide fastener 1 are reversed compared to the above embodiment, and the opening tool 5 may be configured as an opening tool for left-hand insertion. Also, the opening tool 5 in the above embodiment may not have a box body 8 and may be configured as an opening tool for both sides. In this case, the slide fastener 1 may have multiple sliders 3. Furthermore, the slide fastener 1 in the above embodiment may not have an opening tool 5 and may instead have a bottom stopper.
[0086] 1...Slide fastener, 10A...First fastener stringer, 10B...Second fastener stringer, 11...Fastener tape, 110...Side edge, 12...Element row, 2A, 2B...Element, 20...Element pair, 21...Element body, 211A, 211B...First body side, 212A, 212B...Second body side, 21S...Tape groove, 22 ...engaging part, 221...neck part, 222...head part, 223...recess, 224...protrusion, 225...curved surface, 227...engaging side surface, 227A, 227B...inclined surface, 22S...engaging groove, 23...fin part, 231...first edge, 232...second edge, 233...tip, 3...slider, 31...slider body, 311...upper wing plate, 312...lower wing plate, 313...guide post, 314A, 314B 315A, 315B...flange, 32...pull handle, 4...upper stopper, 5...opening mechanism, 6...butterfly rod, 61...butterfly rod body, 611A, 611B...butterfly rod body side, 61S...tape groove, 62...butterfly rod projection, 621...recess, 622...protrusion, 623...butterfly rod projection side, 623A, 623B...butterfly rod inclined surface, 62A, 62B...divided projection, 62S...engagement groove, 7...box rod, 71...box rod body Part, 711A, 711B... Side of the box bar body, 71S... Tape groove, 72... Box bar projection, 721... Recess, 722... Protrusion, 73... Fin, 74... Notch, 8... Box body, 81... Base, 82... Box wall, 91... Slide core, 911... Side edge, 92... Fixing core, C1... First insertion passage, C2... Second insertion passage, G1, G2... Gap, P1, P2... Protruding tip position, RS... Accommodation space.
Claims
1. A first fastener stringer (10A) and a second fastener stringer (10B) are combined with each other, and each of the first fastener stringer (10A) and the second fastener stringer (10B) comprises a fastener tape (11) and a plurality of elements (2A, 2B) arranged in the longitudinal direction of the fastener tape (11), and each element (2A, 2B) comprises an element body portion (21) attached to the side edge portion (110) of the fastener tape (11) and an engaging portion (22) that protrudes from the element body portion (21) to one side in the width direction perpendicular to the longitudinal direction and engages with the other element (2A, 2B) in the combined pair, and the engaging portion (22) comprises a convex portion (224) protruding to one side in the longitudinal direction and a concave portion (223) opening between the convex portion (224) and the element body portion (21), A slide fastener comprising an engaging side surface (227) facing the other side in the longitudinal direction, wherein the engaging portion (22) of the element (2A) of the first fastener stringer (10A) and the engaging portion (22) of the element (2B) of the second fastener stringer (10B) are alternately arranged in the longitudinal direction in opposite directions to each other such that the convex portion (224) fits into the concave portion (223) and the engaging side surfaces (227) face each other, and the engaging side surfaces (227) have a pair of inclined surfaces (227A, 227B) that are inclined with respect to the thickness direction which is perpendicular to the longitudinal direction and the width direction, respectively, and form a taper.
2. The slide fastener according to claim 1, wherein the element body portion (21) faces in the same direction as the engaging side surface (227) in the longitudinal direction and has a pair of first body side surfaces (211A, 211B) arranged on both sides in the thickness direction relative to the fastener tape (11), and the inclination angle (θ3) of the inclined surfaces (227A, 227B) with respect to the thickness direction is greater than the inclination angle (θ1) of the first body side surfaces (211A, 211B) with respect to the thickness direction.
3. The slide fastener according to claim 1 or 2, wherein the element body portion (21) faces in the same direction as the protruding direction of the convex portion (224) in the longitudinal direction and has a pair of second body side surfaces (212A, 212B) arranged on both sides in the thickness direction relative to the fastener tape (11), and the inclination angle (θ3) of the inclined surfaces (227A, 227B) with respect to the thickness direction is greater than the inclination angle (θ2) of the second body side surfaces (212A, 212B) with respect to the thickness direction.
4. The slide fastener according to any one of claims 1 to 3, wherein the engaging side surface (227) extends along one direction inclined with respect to the width direction so as to face the opposite direction from the protruding direction of the engaging portion (22).
5. The slide fastener according to any one of claims 1 to 4, wherein the engaging side surface (227) of the element (2A) is in slidable contact with the engaging side surface (227) of the other element (2B).
6. The slide fastener according to any one of claims 1 to 5, wherein the elements (2A, 2B) further comprises fin portions (23) extending from the element body portion (21), the engaging portion (22) further comprises an engaging groove (22S) for accommodating the fin portion (23) of the other element (2A, 2B) that is the pairing partner, and when the elements (2A, 2B) are viewed along the thickness direction, the engaging groove (22S) extends along the length direction, and the tip portion (233) of the fin portion (23) is formed in an acute angle.
7. The fastener stringer further comprises a butterfly bar (6) attached to the first fastener stringer (10A), and a box bar (7) attached to the second fastener stringer (10B) and facing the butterfly bar (6), wherein the butterfly bar (6) comprises a butterfly bar body portion (61) that holds the side edge portion (110) of the fastener tape (11), and a butterfly bar projection portion (62) that protrudes from the butterfly bar body portion (61) toward the box bar (7) and fits into the box bar (7), and the butterfly bar projection portion (62) has a butterfly bar projection side surface (623) that faces toward the element (2A) side of the first fastener stringer (10A) and is inclined with respect to the width direction so as to face away from the box bar (7) side. The side surface of the butterfly bar projection (623) faces the engaging side surface (227) of the element (2B) adjacent to the box bar (7) in the second fastener stringer (10B), according to any one of claims 1 to 6.
8. The slide fastener according to claim 7, wherein the side surface of the butterfly bar projection (623) has a pair of butterfly bar inclined surfaces (623A, 623B) that are inclined with respect to the thickness direction and form a taper.
9. The slide fastener according to claim 8, wherein the butterfly bar body portion (61) is arranged on both sides in the thickness direction with respect to the side edge portion (110) of the fastener tape (11), and has a pair of butterfly bar body side surfaces (611A, 611B) facing the element (2A, 2B) side of the first fastener stringer (10A), and the inclination angle of the butterfly bar inclined surfaces (623A, 623B) with respect to the thickness direction is greater than the inclination angle of the butterfly bar body side surfaces (611A, 611B) with respect to the thickness direction.
10. The slide fastener according to any one of claims 7 to 9, wherein the elements (2A, 2B) have a symmetrical shape in the thickness direction, and the butterfly bar projection (62) has an asymmetrical shape in the thickness direction.
11. The slide fastener according to any one of claims 7 to 10, wherein the protruding tip position (P1) of the butterfly bar projection (62) is located on the side edge portion (110) of the fastener tape (11) of the first fastener stringer (10A) than the protruding tip position (P2) of the engaging portion (22) of the element (2A) of the first fastener stringer (10A).