TWI481358B - Zipper - Google Patents

Description

zipper

The present invention relates to a zipper, and more particularly to a zipper in which a plurality of fastener elements are coupled by a joint portion.

As a zipper of the prior art, it is known that a side chain portion of the opposite side of the pair of chain fabrics is connected to a plurality of fastener elements by the embedded support strands (for example, refer to Patent Document 1). .

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. 56-89204

However, in the zipper described in Patent Document 1, for example, when the fastener element is sewn to the fastener by a sewing machine, the posture of the fastener element may be unstable, and it may be difficult to stitch the fastener element to the fastener fabric in a stable posture. Moreover, when the fastener element is sewn in an unstable posture, the mounting strength of the chain cloth and the fastener element is insufficient, so that the fastener element moves relative to the chain cloth, or the fastener elements cannot be properly engaged with each other.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a zipper in which a plurality of fastener elements connected by a joint portion can be sewn to a chain cloth in a stable posture, thereby improving the attachment strength of the chain cloth and the fastener elements.

The above object of the present invention is achieved by the following constitution.

(1) A zipper comprising: a pair of chain fabrics; and a chain of sprocket having a plurality of side-by-side portions spaced apart from each other at a fixed interval along a pair of chain fabrics a sprocket; and a sliding member slidably mounted along the sprocket row and engaging the sprocket to separate the sprocket; and the sprocket includes: a body portion mounted on the chain cloth; the tooth portion facing the chain cloth a neck portion extending outward in the width direction and contracting in the longitudinal direction of the chain cloth; and an engaging head extending from the front end portion of the neck portion and protruding from the neck portion in the longitudinal direction of the chain cloth, and the fastener element The fastener element rows are connected by the connecting portion, and are attached to the fastener fabric by two or more sutures in which the surfaces of the fastener elements are arranged in the width direction of the fastener fabric.

(2) The slide fastener according to (1), wherein the fastener element has a first surface in contact with the fastener fabric and a second surface on the opposite side thereof; and the first surface side has a tooth body portion and a neck extending from the tooth body portion a portion and an engaging head extending from the front end of the neck; the second surface side has a width extending outward from the tooth portion toward the width direction of the chain cloth, and the dimension of the chain fabric decreases in size as the front end The head.

(3) The zipper according to (1) or (2), wherein a receiving groove for accommodating the suture is formed on a surface of the fastener element.

(4) The zipper according to any one of (1) to (3), wherein the plurality of sprocket systems are connected by a pair of connecting portions to form a sprocket row, and are attached to the chain cloth by two stitches.

(5) The zipper according to (4), wherein the two sutures are disposed between the pair of connecting portions.

(6) The slide fastener according to (1), wherein the fastener element has a first surface that is in contact with the fastener fabric and a second surface that is opposite to the fastener fabric, and the first surface is formed with a curved shape that is concavely curved toward the second surface. unit.

According to the zipper of the present invention, the fastener elements are connected by the connecting portion to form the element rows, and are attached to the chain by the two or more stitches arranged on the surface of the fastener element along the width direction of the chain cloth. Therefore, the fastener element can be attached to the chain cloth in a stable posture, thereby improving the mounting strength of the chain cloth and the fastener element.

Hereinafter, each embodiment of the slide fastener of the present invention will be described in detail based on the drawings. In the following description, regarding the chain cloth, the front side refers to the near side of the paper surface of FIG. 1 (the side of the slider is provided on the upper side of the slider), and the back side refers to FIG. 1 The back side of the paper surface (the side of the lower side of the slider is not provided with the pull tab), the front side refers to the upper side with respect to the paper surface of Fig. 1 (the sliding member is engaged in such a manner that the following element rows are meshed) The direction of the side of the movement refers to the lower side of the paper surface of Fig. 1 (the side on which the slider moves in such a manner that the following element rows are separated), and the so-called left side refers to the paper surface of Fig. 1 On the left side, the right side refers to the right side with respect to the paper surface of FIG. 1. Regarding the slider, the upper side refers to the near side of the paper surface of FIG. 1, and the lower side refers to the paper surface of FIG. In the back side, the front side refers to the upper side with respect to the paper surface of FIG. 1, and the rear side refers to the lower side with respect to the paper surface of FIG. 1, and the left side refers to the left side with respect to the paper surface of FIG. Refers to the right side of the paper of Figure 1. Here, the front-back direction means a direction perpendicular to the chain surface, and the left-right direction means a direction that is horizontal to the chain surface and orthogonal to the front-rear direction. Further, the left and right directions of the chain cloth and the slider are also referred to as the width direction. Moreover, the front and rear directions of the chain cloth are also referred to as the length direction.

(First embodiment)

First, a first embodiment of a slide fastener according to the present invention will be described with reference to Figs. 1 to 9 .

As shown in Fig. 1, the slide fastener 10 of the present embodiment includes a pair of left and right chain fabrics 20 which are knitted or woven, and fastener elements which are respectively provided on the opposite side fabric edge portions 20a of the pair of left and right chain fabrics 20 The row 30, the left and right element rows 30 are engaged, the separated slider 40, the sprocket 31 covering the front end portions of the left and right element rows 30 are formed to form the upper stop portion 11, and the two chain rows 30 are covered. Both of the sprocket 31 of the rear end portion 30 are formed to form the lower stopper portion 12. Further, the left and right element rows 30 are engaged and separated by moving the slider 40 in the front-rear direction. Furthermore, the lower stop portion 12 may also be an opening and closing insert including a pin, a pin, and a case. In addition, in FIG. 1 and FIG. 2, the following suture 38 is abbreviate|omitted and shows each part.

The pair of right and left sprocket rows 30 include a plurality of sprocket teeth 31 which are arranged in a row along the longitudinal direction of the chain side edge portion 20a of the chain fabric 20 and are independent of each other; and a pair of cross-sectional circular links The portion 22 is connected to the adjacent fastener elements 31 and arranged in parallel along the width direction of the chain cloth 20 in parallel with each other. Further, the plurality of fastener elements 31 and the connecting portion 22 are integrally molded by injection molding using a synthetic resin such as polyamine, polyacetal, polypropylene or polybutylene terephthalate. Further, the fastener element 31 is not limited to the above synthetic resin, and may be made of metal.

By arranging one pair of the connecting portions 22 in parallel in this manner, the plurality of sprocket teeth 31 are integrally coupled to each other, and the posture (positional relationship) of each of the sprocket teeth 31 is stably maintained. Thereby, the fastener element 31 can be sewn to the chain fabric 20 in a stable posture, thereby improving the mounting strength of the chain fabric 20 and the fastener element 31. Moreover, the sewing operation can be performed easily and surely. Further, the connecting portion 22 may be a member different from the sprocket 31, for example, a wire harness member such as a wire. In this case, the sprocket 31 is equally spaced along the longitudinal direction of the chain fabric 20 The wire harness member is injection molded, and the wire harness member is insert-molded into the fastener element 31.

As shown in FIG. 2 to FIG. 5, the fastener element 31 includes a back surface portion 32A which is a first surface which is in contact with the chain cloth 20, and a surface portion which is a second surface which is disposed on the side opposite to the back surface portion 32A and which is disposed on the front side. 32B.

As shown in FIG. 4, the back surface portion 32A side includes a tooth body portion 33 attached to the chain cloth 20, and a neck portion 34 which is outward from the tooth body portion 33 in the width direction (chain width direction) of the chain cloth 20. (in the right direction in the drawing, and extending in the direction of the opposite element rows 30 in the state of being attached to the chain fabric 20), and contracting along the longitudinal direction of the chain fabric 20 (the longitudinal direction of the chain fabric); and the engaging head The portion 35 extends outward from the front end portion of the neck portion 34 toward the width direction of the chain cloth 20, and is raised in the longitudinal direction of the chain cloth 20 from the neck portion 34. Further, the dimension of the neck portion 34 in the longitudinal direction of the chain is smaller than the tooth body portion 33 and the engaging head portion 35. Further, the dimension of the meshing head portion 35 in the longitudinal direction of the chain is larger than the tooth body portion 33.

The tooth body portion 33 is a substantially rectangular cube having a long width in the width direction of the lower chain fabric 20, and a pair of coupling portions 22 are formed on both side surfaces in the longitudinal direction of the chain cloth 20. The pair of connecting portions 22 connect the tooth portions 33 of the adjacent sprocket 31 to each other, and include a connecting portion that connects the engaging head portion 35 side of each of the tooth portions 33, and is separated from the connecting portion. The other connecting portion that connects the tooth body portion 33 opposite to the meshing head portion 35 is spaced apart. Further, on the end surface of the tooth body portion 33 opposite to the meshing head portion 35, a convex curved surface 33a whose central portion in the longitudinal direction of the chain cloth 20 is convex toward the opposite side of the meshing head portion 35 is formed. Further, a curved portion 33b (see FIG. 5) that is concavely curved in the direction of the surface portion 32B is formed between the pair of connecting portions 22 on one of the back surface (the surface in contact with the chain cloth 20) of the tooth body portion 33. Further, the engaging head portion 35 is engaged with the neck portion 34 of the adjacent sprocket 31 when the left and right element rows 30 are engaged. As shown in FIG. 5, the convex curved surface 33a side of the tooth body portion 33 is formed such that the dimension of the chain cloth 20 in the width direction increases from the back surface portion 32A side toward the surface portion 32B, and decreases toward the position of the connecting portion 22. The connecting portion 22 connecting the adjacent sprocket 31 is thinner than the thickness of the sprocket 31 in the front and back directions, and is located from the side of the tooth portion 33 of the sprocket 31 along the longitudinal direction of the chain 20 (with the chain cloth 20) The direction in which the width direction is orthogonal is extended. The cross-sectional shape of the connecting portion 22 is not limited to a circular shape, and may be a quadrangular shape or a circular shape.

As shown in FIG. 2 and FIG. 3, the front surface portion 32B side has a front side head portion 36 which is approximately triangular in plan view, and the front side head portion 36 extends outward from the tooth body portion 33 in the width direction of the chain cloth 20, and The length of the chain fabric 20 is decreased toward the front end. The front side head portion 36 is formed on the neck portion 34 on the side of the back surface portion 32A and the front side of the engaging head portion 35. That is, the neck portion 34 and the engaging head portion 35 are extended from the side of the back surface portion 32A of the tooth body portion 33, and the front side head portion 36 is extended from the surface portion 32B side of the tooth body portion 33.

Further, in the surface and the side surface of the tooth portion 33 between the pair of connecting portions 22, two concave receiving grooves 37 for respectively accommodating the following two stitches 38 are provided on both sides of the tooth portion 33. The surface is continuously formed and formed in parallel with the joint portion 22. Thereby, the two sutures 38 are disposed between the pair of coupling portions 22.

As shown in FIG. 1, FIG. 5, and FIG. 6, the slider 40 is provided with the upper wing 41 and the lower blade 42 in parallel in the up-and-down direction, and the upper blade 41 and the lower blade 42 are connected to the front end. a guide post 43, a side guide 44 formed along the left and right side edges of the upper blade 41 and the lower blade 42, a tab mounting post 45 formed on the upper surface of the upper blade 41, and a swingable mounting The pull tab 46 of the post 45 is mounted on the pull tab. Thereby, the left and right introduction ports 47 separated by the guide post 43 are formed in the front portion of the slider 40, and the engagement opening 48 is formed in the rear portion of the slider 40. Further, between the upper blade 41 and the lower blade 42, a substantially Y-shaped sprocket guiding passage 49 that connects the left and right introduction ports 47 and the engaging opening 48 is formed, and the sprocket guiding passage 49 is configured. A pair of left and right chain rows 30 are inserted through the passage. Furthermore, the side guide 44 may be included only on one side of the upper wing 41 and the lower wing 42, and the pull tab mounting post 45 and the pull tab 46 may be included in the lower wing 42.

Further, in the present embodiment, when the operation slider 40 is moved, the convex curved surface 33a of the fastener element 31 is slidably attached to the side guide 44, so that the contact area between the side guide 44 and the convex curved surface 33a becomes smaller than that of the flat surface. . Thereby, the sliding resistance when the slider 40 is moved can be reduced, so that the slider 40 can be operated with a small force.

Further, as shown in FIG. 5, the element row 30 is chained along one side (for example, the surface side) of the chain cloth 20 by using two stitches 38 arranged in the width direction of the chain cloth 20. The cloth side edge portion 20a is sewn to each of the fastener elements 31, and is attached to the chain fabric 20. Two stitching lines 38 are disposed across the surface of the tooth body portion 33 of the adjacent fastener element 31 along the longitudinal direction of the chain fabric 20. Between the sprocket 31, the fastener element 38 is sewn to the chain fabric 20 by sewing the suture 38 to the chain fabric 20. The two sutures 38 include the engaging head portion disposed on the tooth body portion 33. One of the stitches 38 on the 35 side and another stitch 38 disposed on the side of the engaging head portion 35 of the tooth body portion 33 are spaced apart from the one stitch 38. Further, the number of the sutures 38 may be three.

At this time, since the two sutures 38 are respectively accommodated in the two accommodation grooves 37 of the fastener elements 31, the two sutures 38 do not fall off from the fastener elements 31. Further, since the chain fabric 20 is sewn so as to be in close contact with the curved portion 33b on the back surface of the tooth body portion 33, the attachment strength of the chain cloth 20 and the fastener element 31 is improved.

The zipper 10 constructed in this manner is attached to the upper surface of the engaging head portion 35 of one of the sprocket teeth 31 and the lower surface of the front side head portion 36 of the adjacent other sprocket 31 as shown in FIGS. 6 and 7. In the connected state, the engaging heads 35 of the left and right sprocket teeth 31 mesh with each other. Further, as shown in FIG. 7, the neck portion 34 and the engaging head portion 35 are formed in a substantially trapezoidal shape in a cross section from the center in the front-back direction toward the back side, and the front side head portion 36 is formed in the front-back direction. The cross section in which the center is tapered toward the front side is approximately trapezoidal. Thereby, the left and right sprocket teeth 31 in the meshed state are engaged with each other with a gap therebetween. Therefore, as shown in Fig. 8, even if the slide fastener 10 is bent in the surface direction, the fastener elements 31 are hard to contact each other, and therefore, it is easy to maintain the good meshing state for bending. Further, even if the zipper 10 is bent in the direction opposite to the back surface of FIG. 8, it is formed into a shape that is tapered from the center in the front-back direction toward the back side, and is easily bent.

As described above, according to the slide fastener 10 of the present embodiment, the fastener elements 31 are connected by the pair of coupling portions 22 to constitute the element row 30, and the surfaces of the fastener elements 31 are arranged along the width direction of the chain cloth 20. Since the two stitches 38 are disposed and attached to the chain cloth 20, the fastener elements 31 can be attached to the chain cloth 20 in a stable posture, so that the attachment strength of the chain cloth 20 and the fastener elements 31 can be improved.

Further, according to the slide fastener 10 of the present embodiment, since the two storage grooves 37 that accommodate the two sutures 38 are formed in the tooth body portion 33, the two sutures 38 do not fall off from the fastener elements 31. Thereby, the fastener element 31 can be reliably attached to the chain cloth 20.

Further, according to the slide fastener 10 of the present embodiment, since the two stitches 38 are disposed between the pair of coupling portions 22, the pair of coupling portions 22 can prevent the suture 38 from coming into contact with the external member. Thereby, the abrasion of the suture 38 due to the contact can be prevented, so that the durability of the zipper 10 can be improved.

Further, according to the slide fastener 10 of the present embodiment, the curved portion 33b that is concavely curved toward the surface portion 32B is formed on the back surface portion 32A of the fastener element 31. Therefore, when the fastener element 31 is sewn to the fastener fabric 20, the fastener fabric is attached. Since the 20 is in close contact with the curved portion 33b, the attachment strength of the chain cloth 20 and the fastener element 31 can be improved.

Further, as a modification of the embodiment, the element row 30 may be applied to the concealed slide 50 shown in Fig. 9 . The concealed zipper 50 includes a pair of left and right chain fabrics 51, and a bent edge portion 51b formed by bending a chain side edge portion 51a opposite to the pair of right and left chain cloths 51 in a substantially U-shape, respectively. The sprocket row 30 and the slider 60 that engages the left and right sprocket rows 30 are engaged, and the zipper 50 is brought into close proximity to the left and right bent edge portions 51b by the meshing of the sprocket rows 30. Preferably, the contact is made, and it is difficult to see the element row 30 from the surface side.

The slider 60 includes a lower wing plate 61; a pair of right and left side guide plates 62 having an inverted L-shaped cross section, and the like, and the side wall portions 62a which are respectively erected along the left and right side edges of the lower wing plate 61, and the left and right sides A pair of right and left upper plate portions 62b extending from the upper end of the side wall portion 62a in a direction in which they approach each other; a guide post (not shown) is erected from the front end portion of the lower blade 61 toward the pair of right and left upper plate portions 62b And a pull tab (not shown) that is swingably attached to the guide post.

(Second embodiment)

Next, a second embodiment of the slide fastener of the present invention will be described with reference to Figs. 10 and 11 . In the drawings, the same or equivalent portions as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted or simplified.

In the present embodiment, as shown in FIGS. 10 and 11, a wide receiving groove 71 for accommodating the suture 38 is formed on the surface of the tooth portion 33 of the fastener element 31. Moreover, the connection portion 22 on the convex curved surface 33a side of the tooth body portion 33 is disposed substantially at the center portion in the width direction of the accommodation groove 71. Further, the sprocket 31 is a total of three stitches 38 that pass through the two stitches 38 between the pair of connecting portions 22 and one connecting portion 22 on the side of the convex curved surface 33a through the outer side of the width direction. The stitch 38 is stitched to the chain cloth 20.

Further, on the surface of the chain fabric 20, a film containing a thermoplastic synthetic resin (thermoplastic elastomer) is adhered by an adhesive, or a molten resin is applied thinly to form a water-repellent layer 72. Further, since the waterproof layer 72 is formed on the chain fabric 20, the sprocket 31 can be used as the back side, and a zipper having waterproof performance can be obtained by preventing rainwater or the like from entering.

Other configurations and operational effects are the same as those of the first embodiment described above.

(Third embodiment)

Next, a third embodiment of the slide fastener of the present invention will be described with reference to Figs. 12 and 13 . In the drawings, the same or equivalent portions as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted or simplified.

In the present embodiment, as shown in FIGS. 12 and 13, the sprocket 31 is coupled by a flat connecting portion 81. The connecting portion 81 is integrally formed with the fastener element 31 in the same manner as the connecting portion 22 described above. Further, the two stitches 38 are passed through the connecting portion 81, and the fastener elements 31 are sewn to the chain cloth 20. Further, the width of the connecting portion 81 is preferably between the vicinity of the neck portion 34 of the sprocket 31 and the vicinity of the convex curved surface 33a, and at least one suture 38 can be inserted (stitched) into the width of the connecting portion 81.

As described above, according to the slide fastener 10 of the present embodiment, since the fastener elements 31 are coupled by one flat connecting portion 81, the posture of the fastener elements 31 can be made more stable. Since the two stitches 38 penetrate the flat connecting portion 81, the attachment strength of the chain cloth 20 and the fastener elements 31 can be further improved.

Other configurations and operational effects are the same as those of the first embodiment described above.

(Fourth embodiment)

Next, a fourth embodiment of the slide fastener of the present invention will be described with reference to Fig. 14 . In the drawings, the same or equivalent portions as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted or simplified.

In the present embodiment, the sprocket 91 shown in Fig. 14 is used instead of the sprocket 31. The sprocket 91 has the same shape as the front and back, and is identical to the sprocket 31, and includes a tooth body portion 92 in which two storage grooves 93 are formed, and the tooth body portion 92 is outward in the width direction of the chain cloth 20 (in the drawing) The neck portion 94 extending in the right direction and contracting in the longitudinal direction of the chain cloth 20 extends outward from the front end portion of the neck portion 94 toward the width direction of the chain cloth 20 and is opposite to the neck portion 94 in the chain cloth 20 The engagement head portion 95 extending in the longitudinal direction, the introduction portion 96 extending from the side surface of the neck portion 94, and the introduction portion 96 formed at the end portion of the engagement head portion 95 and the fastener element 91 on the other side are fitted. Part storage groove 97. Further, the fastener element 91 is the same as the fastener element 31 described above, and is sewn to the chain fabric 20 by two stitches 38.

Other configurations and operational effects are the same as those of the first embodiment described above.

The present invention is not limited to the embodiments described above, and may be appropriately modified without departing from the spirit of the invention.

For example, in the above embodiment, the back surface portion 32A of the fastener element 31 can be formed into a flat surface without forming the curved portion 33b.

10. . . zipper

11. . . Upper stop

12. . . Lower stop

20. . . Chain cloth

20a. . . Chain side edge

twenty two. . . Linkage

30. . . Chain row

31. . . Chain teeth

32A. . . Back part (first side)

32B. . . Surface part (second side)

33. . . Tooth body

33a. . . Convex surface

33b. . . Bending

34. . . neck

35. . . Meshing head

36. . . Head side head (head)

37. . . Storage slot

38. . . Suture

40. . . Slider

41. . . Upper wing

42. . . Lower wing

43. . . Guide column

44, 62. . . Side guide

45. . . Pull tab mounting post

46. . . Pull tab

47. . . Guide

48. . . Mating port

49. . . Chain guide channel

50. . . Invisible zipper

51. . . Chain cloth

51a. . . Chain side edge

51b. . . Bent edge

60. . . Slider

61. . . Lower wing

62a. . . Side wall

62b. . . Upper plate

71. . . Storage slot

72. . . Waterproof layer

81. . . Linkage

91. . . Chain teeth

92. . . Tooth body

93. . . Storage slot

94. . . neck

95. . . Meshing head

96. . . Import department

97. . . Inlet storage slot

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a front view showing a first embodiment of a slide fastener according to the present invention;

Figure 2 is an enlarged perspective view of the chain of teeth in an unmated state;

Figure 3 is a surface view of the element row shown in Figure 2;

Figure 4 is a rear view of the chain of teeth shown in Figure 2;

Figure 5 is a cross-sectional view taken along line A-A of Figure 1;

Figure 6 is a magnified surface view showing the main part of the state in which the fastener elements are engaged or disengaged in the slider;

Figure 7 is a cross-sectional view taken along line B-B of Figure 1;

Figure 8 is a cross-sectional view for explaining a state in which the slide fastener shown in Figure 7 is bent in the front and back directions;

Fig. 9 is an enlarged cross-sectional view showing a modification of the slide fastener of the first embodiment;

Figure 10 is a cross-sectional view showing a second embodiment of the slide fastener of the present invention;

Figure 11 is a surface view of the element row shown in Figure 10;

Figure 12 is a cross-sectional view showing a third embodiment of the slide fastener of the present invention;

Figure 13 is a surface view of the element row shown in Figure 12;

Fig. 14 is a view showing the surface of the element row of the fourth embodiment of the slide fastener of the present invention.

20. . . Chain cloth

20a. . . Chain side edge

twenty two. . . Linkage

30. . . Chain row

31. . . Chain teeth

32A. . . Back part (first side)

32B. . . Surface part (second side)

33. . . Tooth body

33a. . . Convex surface

34. . . neck

35. . . Meshing head

36. . . Head side head (head)

37. . . Storage slot

Claims (2)

A zipper, characterized in that it is a zipper (10), comprising: a pair of chain cloths (20); a chain of teeth (30) having a side edge portion along the opposite side of the pair of chain cloths (20a) a plurality of sprocket teeth (31) arranged in parallel at a fixed interval; and a slider (40) slidably mounted along the sprocket row, and the meshing teeth can be engaged and disengaged; Further, the fastener element includes: a tooth body portion (33) attached to the chain cloth; and a neck portion extending outward from a width direction of the chain cloth from the tooth body portion and contracting in a longitudinal direction of the chain cloth (34) And an engaging head portion (35) extending from the front end portion of the neck portion and protruding from the neck portion in the longitudinal direction of the chain cloth, and the fastener element is coupled by a pair of connecting portions (22) The chain element row is configured to be attached to the chain cloth by two sutures (38) arranged on the surface of the fastener element along the width direction of the chain cloth, and the two sutures (38) are arranged Between the pair of connecting portions (22), two storage grooves (37, 93) of the two sutures (38) are respectively accommodated on both sides of the tooth portion (33). The surface is continuously formed and formed in parallel with the connecting portion (22), and the element (31) has a first surface (32A) in contact with the chain cloth (20) and a second surface (32B on the opposite side) The first surface side has the tooth body portion (33), the neck portion (34) extending from the tooth body portion, and the engaging head portion (35) extending from the front end portion of the neck portion. The second surface side has a width from the tooth body portion toward the chain cloth a front side head portion (36) which is extended outward in the direction and which is reduced in size in the longitudinal direction of the chain cloth toward the front end, on the upper surface of the engaging head portion (35) of the fastener element (31), and The engaging heads (35) of the left and right sprocket teeth (31) are engaged with each other in a state in which the lower surface of the front side head (36) of the adjacent sprocket (31) abuts. The zipper of claim 1, wherein the first surface is formed with a curved portion (33b) that is concavely curved toward the second surface (32B).