TWI584753B - Buckle - Google Patents

Description

buckle

The present invention relates to a buckle including a plug and a socket that can be engaged and disengaged from each other, and can be used for belts or tapes and other components. The respective parts are linked and disconnected from each other.

In the past, a buckle that is detachably connected to the two connection objects is, for example, a buckle disclosed in Patent Document 1. The buckle includes a plug and a socket, and the plug has a pair of leg portions extending in parallel from both end portions in the width direction, and a pair of engaging protrusions protruding from the front end portions of the pair of leg portions toward the front and rear sides, respectively. unit. The socket has: an upper plate and a lower plate extending from the base; the upper side wall portion and the lower side wall portion are protruded so as to face each other along both sides of the width direction of the upper plate and the lower plate; the stepping portion can Each of the pair of leg portions inserted between the upper and lower plates is engaged with a pair of engaging projections; a slit is formed between the upper side wall portion and the lower side wall portion, and an end portion of the plug insertion side is opened to provide a slit a part of the leg portion is inserted; and the guide surface is formed by the inner side surfaces of the upper side wall portion and the lower side wall portion, and the pair of engaging protrusions of the pair of leg portions inserted between the upper and lower plates are guided to the engaged portion Engage the steps. Further, the thickness of the pair of engaging projections is set to be larger than the width of the slit.

Further, the buckle disclosed in Patent Document 2 includes the same basic configuration as that of Patent Document 1, and has a configuration in which the shape of the slit formed between the upper side wall portion and the lower side wall portion of the socket is from the upper plate. The plug insertion port between the lower plates and the center portion of the socket is formed so as to be wide enough for the leg portion of the plug to pass therethrough, and is formed to be narrow from the center portion to the vicinity of the engaged portion. Inside the leg portion of the plug, a rib is formed in the extending direction of the leg portion, and the width of the rib portion is thicker than the narrow slit and thinner than the wide slit. [Prior Art Document] [Patent Literature]

[Patent Document 1] International Publication No. WO2014/002235 (Patent Document 2) Japanese Patent Laid-Open No. Hei 7-289310

[Problems to be Solved by the Invention] In the buckle disclosed in Patent Document 1, the size of the pair of engaging projections is larger than the width of the slit, but between the engaging projection and the base end of the foot. The thickness of the leg portion is narrower than the width of the slit, and in the case where the plug is obliquely inserted into the plug insertion opening portion of the socket, a thin portion of the leg portion is inserted into the slit, and the base end portion of the plug is fitted to the slit When the slit is engaged, the engaging projection cannot be locked to the engaging step, or the leg is fitted into the slit and cannot be moved.

Further, in the case of the buckle disclosed in Patent Document 2, the slit is not located at a position apart from the plug insertion opening, and the rib is configured to guide the insertion of the plug. Therefore, in the same manner as described above, in the case where the leg portion of the plug is obliquely inserted into the socket via the portion of the wide slit, there is a case where the engaging projection portion and the engaged portion cannot be engaged, or the leg portion of the plug Or the base end portion of the leg is fitted to the slit portion and cannot be moved.

The present invention has been made in view of the problems of the background art, and an object of the invention is to provide a buckle which is excellent in operability and can be surely engaged even when a plug is inserted obliquely into a socket. [Means for solving the problem]

The present invention is a buckle including a plug and a socket that can be coupled to each other and disconnected and attached to a predetermined member, and the plug includes a pair of leg portions respectively formed at positions close to the front end portion of the pair of the leg portions The engagement protrusions include a guide portion at a position where the pair of the leg portions are symmetrical with respect to a center line between the pair of the leg portions, and each side edge portion on the side of the center line includes a guide portion. The guide portion has a thickness in the front and back directions and includes a rib extending continuously from the engaging projection, the socket including: an upper surface portion and a lower surface portion forming a receiving space into which the leg portion is inserted, and a pair of upper side wall portions and a pair of lower side wall portions that are disposed on both side edges of the upper surface portion and the lower surface portion and that face each other, and a pair of the upper side wall portions and a pair of The side wall portions are provided in a pair of slits, and the slits are formed in a direction from the insertion opening of the receiving space into the leg portion, the guiding portion and the upper side wall portion and / or the lower side wall portion abuts and cannot be inserted into The slit.

Further, in the buckle according to claim 2, the dimension of the guide portion in the front and back directions is formed larger than the dimension of the slit in the front and back directions. In the buckle according to claim 3, a belt insertion portion is provided at a base end portion of the leg portion, and the belt insertion portion includes a first bar and a second bar, and the leg portion is from the Both ends of the second rod extend. The pair of the leg portions of the buckle according to claim 4 are connected to the base end portion by a U-shaped bridge.

In the rib of the buckle according to claim 5, one end is located at the engaging projection and extends toward the proximal end side of the leg, and a stopper is provided at the other end of the rib (stopper) And the stopper portion abuts against the upper side wall portion and/or the lower side wall portion in a state in which the plug is inserted into the socket.

Further, in the buckle according to the sixth aspect of the invention, the pair of the upper side wall portions in the accommodating space and the inner wall surface of the pair of the lower side wall portions are provided as a guide surface that abuts when the leg portion is inserted. The shape of the guide portion formed in the pair of leg portions is formed to coincide with the guide surface. Further, in the buckle according to claim 7, the pair of the upper side wall portions and the pair of the inner wall surfaces of the pair of the lower side wall portions in the accommodating space are mutually in the insertion direction of the pair of the leg portions The interval is formed in a narrower manner. [Effects of the Invention]

The buckle of the present invention is excellent in operability, and even when the plug is inserted obliquely with respect to the socket, the plug and the socket can be easily and surely engaged, and the operability at the time of the engagement operation can be provided. Buckle.

Moreover, according to the buckle of the third aspect, the structure of the plug in which the leg portion is easily bent can be formed in a compact size, and the overall shape of the buckle can be reduced. Further, according to the buckle of the fourth aspect of the invention, it is possible to form a structure in which the leg portion is easily bent and has high strength, and it is possible to form a buckle having excellent operability and high durability.

According to the buckle of the fifth aspect, the insertion position of the plug to the socket is restricted, and stable insertion and engagement can be performed.

According to the buckle of the sixth aspect, the plug is prevented from being loosened during the engagement, and the engagement is stably maintained during use in the connected state. In particular, according to the buckle of the seventh aspect, the insertion of the plug to the socket is facilitated, and the operability is improved.

Hereinafter, a buckle 10 according to an embodiment of the present invention will be described based on FIGS. 1 to 13(a) and 13(b). The buckle 10 includes a plug 12 and a socket 14 into which the plug 12 is fitted and locked, and are attached to members such as a belt or a belt that are arbitrarily coupled and disconnected from each other. In the following description, the direction in which the engagement protrusions 22 of the pair of leg portions 20, which will be described later, of the plug 12 are opposed to each other is referred to as the left-right direction, and the direction perpendicular to the left-right direction and the protruding direction of the leg portion 20 are referred to as front and rear directions. The direction, which is orthogonal to the left-right direction and the front-back direction, is called the front-back direction or the thickness direction.

The plug 12 is formed by, for example, a synthetic resin such as polyacetal, polyamide, or polypropylene. The plug 12 includes a leg portion 20 that is inserted into the socket 14, an engaging projection 22 that is integrally provided at a position of the leg portion 20 near the front end portion 20a, and an opposite side of the engaging projection 22 and integrally provided at the leg portion 20 The tape insertion portion 24 of the proximal end portion 20b. The engaging projections 22 are respectively provided to protrude in the front-back direction of the position of the leg portion 20 near the distal end portion 20a, and the locking step portion 22a is provided facing the proximal end portion 20b side of the leg portion 20. The locking step portion 22a is formed to be engageable with the engaged portion 56 of the socket 14 to be described later.

The pair of leg portions 20 protrude from the band insertion portion 24 symmetrically with each other, and are oriented slightly closer to the base end portion than the center portion between the base end portion 20b as the tape insertion portion 24 side and the front end portion 20a where the engagement projection 22 is provided. An operation portion 26 having a shape that gradually protrudes outward in the left-right direction from the distal end portion 20a and the proximal end portion 20b is provided at a position on the side of the 20b side. The dimension of the operation portion 26 in the front and back directions is substantially equal to the thickness direction of the tape insertion portion 24 of the plug 12, and is formed to have a thickness D as shown in FIG.

As shown in FIG. 4, the inner side portion of the pair of operation portions 26 facing each other is provided with a rib portion 28 having a width H smaller than the thickness D of the operation portion 26 in the thickness direction. The rib portion 28 is located at a central portion of the operation portion 26 along the extending direction of the leg portion 20, and the other end portion is continuously formed inside the locking step portion 22a of the engaging projection 22. One end portion of the rib 28 connected to the central portion of the operation portion 26 serves as a stopper portion 31 for abutting the socket 14 when the plug 12 is inserted into the socket 14. In the stopper portion 31, the end edges of the upper side wall portion 47 and the lower side wall portion 48 on the insertion port 40a side of the socket 14 which are described later are abutted. The portion of the rib 28 that is connected to the engagement projection 22 from the stopper portion 31 serves as a guide portion 32 that guides the insertion operation of the plug 12. The guide portion 32 is provided at a position where the pair of leg portions 20 are symmetrical with respect to the center line between the pair of leg portions 20 and each side edge portion on the side of the center line. The outer edge of each of the pair of leg portions 20 and each of the guide portions 32 are obliquely provided so as to approach each other toward the distal end portion 20a. Further, in the front end portion 20a of the leg portion 20, the opposing faces are formed to be slightly spaced apart from each other, and the interval between the pair of leg portions 20 is such that the interval at the position of the tip end portion 20a is formed larger than the locking step. The interval at the position of the portion 22a.

A thin portion 30 located at a central portion in the thickness direction of the operation portion 26 and the rib portion 28 is provided between the operation portion 26 located outside each of the pair of leg portions 20 and the rib portion 28 located inside. The thin portion 30 is formed to have a thickness t which is surrounded by the rib portion 28 and the wall surface of the operation portion 26 from the engagement projection 22, and the portion between the front end portion 26a of the operation portion 26 and the engagement projection 22 is on both sides of the thin portion 30. The side is formed by opening to the left and right and the front and rear directions. Thereby, the thin portion 30 is provided to be engageable with the slit 50 between the upper side wall portion 47 and the lower side wall portion 48 of the socket 14 which will be described later.

In the insertion portion 24, the first rod 34 at the proximal end portion of the plug 12 and the second rod 35 connecting the proximal end portions 20b of the pair of leg portions 20 are arranged in parallel in the left-right direction, and a band insertion is formed therebetween. Hole 24a. Further, a space surrounded by the second rod 35 and the pair of leg portions 20 is also provided with a space for forming the insertion hole 24b. The second rod 35 is located on the surface side of the belt insertion portion 24 in the front and back directions.

A U-shaped bridge portion that connects the vicinity of the distal end portion 20a of the leg portion 20 is integrally provided at a position slightly adjacent to the proximal end portion 20b of the opposing surfaces of the engaging projections 22 of the pair of leg portions 20 Both ends of 36. The bridge portion 36 extends from the inner side surface of the pair of rib portions 28 facing each other with a slight gap therebetween, and is formed in a U-shape in the vicinity of the center portion between the pair of operation portions 26 .

The socket 14 is also formed by, for example, a synthetic resin such as polyacetal, polyamide or polypropylene. The socket 14 includes a fitting portion 40 into which the leg portion 20 of the plug 12 is inserted, and a tape insertion portion 42 on the opposite side of the insertion port 40a of the fitting portion 40. In the tape insertion portion 42, a tape insertion hole 42a through which a tape member or the like is inserted is formed, and a connecting rod 44 that connects the tape member or the like is provided.

In the fitting portion 40 of the socket 14, the upper surface portion 45 and the lower surface portion 46 face each other with a predetermined interval therebetween, thereby forming an insertion space of the plug 12. The end portion of the upper surface portion 45 and the insertion opening 40a side of the lower surface portion 46 is formed such that the central portion thereof protrudes toward the insertion opening 40a side in the front-rear direction from the other portion. On the side edges of the upper surface portion 45, the upper side wall portions 47 projecting toward the lower surface portion 46 side are provided to face each other on both sides in the left-right direction. On the side edges of the lower surface portion 46, the lower side wall portions 48 projecting toward the upper surface portion 45 side on both sides in the left-right direction are also disposed to face each other. The upper side wall portion 47 and the lower side wall portion 48 on both sides in the left-right direction of the fitting portion 40 face each other at a constant interval in the front and rear directions, and a gap therebetween is formed as the slit 50. The width h of the slit 50 is larger than the thickness t of the thin portion 30 of the plug 12, and smaller than the width H of the rib 28. That is, the width H of the rib 28 > the width h of the slit 50 > the thickness t of the thin portion 30.

The size of the fitting portion 40 in the left-right direction is smaller than that of the belt insertion portion 42. As shown in Fig. 1, in a state in which the plug 12 is engaged with the socket 14, the operation portion 26 of the plug 12 is exposed and is located at each of the upper side wall portions 47 and below. One side of the side wall portion 48. The accommodating space 22 into which the engaging projection 22 of the leg portion 20 of the plug 12, the rib portion 28, and the thin portion 30 are inserted is formed inside the fitting portion 40, and the accommodating space 52 is inserted along the insertion opening 40a toward the belt. The side of the portion 42 is formed to have a narrow width in the left-right direction, and the two side walls in the left-right direction are guide surfaces 54 that guide the leg portion 20 of the plug 12 . In other words, the upper wall portion 47 and the inner wall surface of the lower side wall portion 48 facing the accommodating space 52 side form the guide surface 54 so as to conform to the wall surface shape of the outer surface of the guide portion 32 of the leg portion 20, and with the insertion opening 40a. Formed close to each other.

The center of the accommodating space 52 of the fitting portion 40 includes a coupling portion 55 that extends in the front-rear direction from the insertion opening 40a to the belt insertion portion 42, and separates the accommodating space 52 and can withstand the front and back directions. The load is integrally provided between the upper surface portion 45 and the lower surface portion 46. At the opening-side end portion of the connecting portion 55, a groove portion 55a into which the center portion of the bridge portion 36 is fitted and brought into contact is formed. Further, on the surface of the upper surface portion 45, a slightly smooth concave surface is formed along the joint portion 55. An engaged portion 56 to which the locking step portion 22a of the engaging projection 22 of the plug 12 is engaged is provided at an end portion of the fitting portion 40 on the side of the tape insertion portion 42. Further, a surface of the upper surface portion 45 on the side of the insertion hole 42a is provided with a covering portion 45a which extends toward the tape insertion portion 42 and covers the engaging projection 22 in the engaged state of the plug 12, thereby preventing The engaging projection 22 is exposed from the surface side to be conspicuous or touched to an external member.

Next, the engagement operation and the use method of the buckle 10 of the present embodiment will be described below. First, the mounting method of the belt member or the like will be briefly described for the plug 12 of the buckle 10. The first rod 34 and the second rod 35 are provided in the tape insertion portion 24 of the plug 12, and the belt member (not shown) for connection is inserted into the tape insertion hole 24b from the back side of the plug 12, and passes through the second rod 35. The outer circumference is inserted from the surface side of the insertion hole 24a to the back side, and is superposed on the belt member of the belt to be freely adjusted in length. On the other hand, a belt member or the like (not shown) attached to the socket 14 is unadjustably coupled to one of the connecting rods 44.

As shown in FIGS. 2 to 4, the engaging operation of the plug 12 and the socket 14 is such that the leg portion 20 of the plug 12 faces the insertion opening 40a of the socket 14, and the plug 12 is pushed into the socket 14. When the leg portion 20 is inserted into the fitting portion 40, the thin portion 30 is inserted into the slit 50 of the fitting portion 40, and the engaging projections 22 of the leg portion 20 abut against the tape insertion portion 42 of the receiving space 52, respectively. Guide surface 54 of the position. When the plug 12 is further pressed into the socket 14 in a state where the outer sides of the engaging projections 22 are respectively brought into contact with each other, the inclination of the guiding surface 54 is performed with the insertion of the plug 12, and the leg portions 20 are brought closer to each other. Elastic deformation. Then, when the engaging projection 22 of the leg portion 20 passes the end portion of the guiding surface 54, the leg portion 20 is engaged with the engaging portion portion 22a of the engaging projection 22 and the engaged portion 56 of the socket 14 face-to-face. The elastic deformation is restored. Thereby, the engagement protrusions 22 formed on the front and back of each leg portion 20 of the plug 12 are engaged with the engaged portion 56 of the socket 14 so as to face the plug 14 and the socket 14 reliably. Then, the plug 12 is stopped by the end edges of the upper side wall portion 47 and the lower side wall portion 48 forming the insertion opening 40a of the socket 14 coming into contact with the stopper portion 31 of the rib portion 28.

In order to release the connection between the plug 12 and the socket 14, the pair of operation portions 26 are pressed from the outside to elastically deform the engagement projection 22 of the plug 12 to a position that does not face the engaged portion 56 of the socket 14. If the plug 12 and the socket 14 are slightly moved in the direction away from each other in this state, the face-to-face position of the engaging projection 22 and the engaged portion 56 is separated. Thereby, the engagement is easily released.

Further, as shown in FIGS. 12(a) and 12(b), the buckle 10 of the present embodiment can also be used to insert the plug 12 into the socket 14 obliquely with respect to the front-rear direction. The wall portion 30 is inserted into a slit 50, and the corner portion of the engaging projection 22 is guided by the guiding surface 54 of the socket 14, and when further pressed in, the guiding portion 32 of the rib 28 of the plug 12 and the upper side wall portion of the socket 14 47 is in contact with the end of the lower side wall portion 48 and cannot be inserted into the slit 50, and guides the insertion direction of the plug 12 toward the socket 14. Further, at this time, the relationship between the width h of the slit 50 and the thickness t of the thin portion 30 of the plug 12 and the width H of the rib 28 is prevented, and the portion other than the thin portion 30 of the leg portion 20 is prevented from being fitted. In the slit 50 of the socket 14.

Then, when the plug 12 is further pressed into the socket 14, as shown in FIGS. 13(a) and 13(b), the front end portion 20a of the other leg portion 20 and the engaging projection 22 and the guiding surface of the socket 14 are formed. 54 contacts, and the plug 12 is guided in the insertion direction. Thereby, the plug 12 is smoothly guided into the accommodating space 52 of the socket 14. By further pressing the plug 12 into the socket 14, the engagement projection 22 is engaged with the engaged portion 56 as described above, thereby connecting the plug 12 to the socket 14.

According to the buckle 10 of the present embodiment, since the size of each portion of the slit 50 formed in the socket 14 and the leg portion 20 of the plug 12 is in the above relationship, even when the plug 12 is obliquely inserted with respect to the socket 14 Further, there is no case where a part of the plug 12 abuts against the socket 14, and the insertion operation cannot be further performed, or a part of the leg portion 20 is further fitted to the slit 50 to be fixed and cannot be operated. The plug 12 is guided by the guide surface 54 of the socket 14 by the insertion operation, and a part of the socket 14 abuts against the guide portion 32 of the plug 12, and guides the movement of the plug 12 while being appropriately inserted into the positional relationship. The stopper portion 31 of the plug 12 abuts against the end portion of the socket 14 at the insertion port 40a side, and the engagement is completed, and the engagement is completed.

Further, since the pair of leg portions 20 of the plug 12 are connected by the U-shaped bridge portion 36 in the vicinity of the distal end portion 20a, elastic deformation at the time of insertion into the socket 14 is easy, and a constant strength can be maintained. Further, the connecting rod for connecting the proximal end portions 20b of the pair of leg portions 20 is not provided, and only the two rods of the first rod 34 and the second rod 35 are formed in the belt insertion portion 24, so that the plug can be formed. A structure in which the front and rear direction of the 12 is small and the leg portion 20 is easily bent.

Further, the buckle of the present invention is not limited to the above embodiments, and the engaging projection 22 may be provided to protrude from one of the front and back of the leg portion 20. Further, the ribs 28 may extend only from one of the engaging projections 22 of the front and back. In the case where the rib 28 extends only from the engaging protrusion 22 on the surface side in the front and rear directions, when the plug 12 is obliquely inserted into the socket 14 with respect to the front-rear direction, the guide portion 32 of the rib 28 and the upper side wall of the socket 14 The end of the portion 47 is in contact so that it cannot be inserted into the slit 50. Further, the shape of the leg portion 20 or the accommodating space 52 can be appropriately set as long as the relationship between the thin portion 30 of the leg portion 20 and the rib portion 28 and the slit 50 satisfies the above conditions. Further, the shape of the plug 12 or the socket 14 can be appropriately set, and the bridge portion 36 can be provided as needed, and the shape of the tape insertion portion 24 and the tape insertion portion 42 can be appropriately set.

10: buckle 12: plug 14: socket 20: leg portion 20a: front end portion 20b: base end portion 22: engaging projection 22a: locking step portion 24, 42: belt insertion portion 24a, 24b, 42a: with insertion Hole 26: operation portion 26a: front end portion 28 of operation portion: rib portion 30: thin portion 31: stopper portion 32: guide portion 34: first rod 35: second rod 36: bridge portion 40: fitting portion 40a : insertion port 44 : connecting rod 45 : upper surface portion 45 a : covering portion 46 : lower surface portion 47 : upper side wall portion 48 : lower side wall portion 50 : slit 52 : receiving space 54 : guiding surface 55 : connecting portion 55 a : groove Portion 56: engaged portion D: thickness of the operating portion H: width of the rib h: width of the slit t: thickness of the thin portion

Fig. 1 is a perspective view showing an engaged state of a buckle according to an embodiment of the present invention. Fig. 2 is a perspective view showing a non-engaged state of the buckle of the embodiment. Fig. 3 is a front elevational view showing the non-engaged state of the buckle of the embodiment. 4 is a right side view showing a non-engaged state of the buckle of the embodiment. Fig. 5 is a bottom view of the plug of the buckle of the embodiment. Fig. 6 is a longitudinal sectional view of the socket of the buckle of the embodiment. Fig. 7 is a plan view showing the socket of the buckle of the embodiment. Fig. 8 is a partially broken front view showing the engaged state of the buckle of the embodiment. Fig. 9 is a cross-sectional view taken along line A-A of Fig. 8; Fig. 10 is a cross-sectional view taken along line B-B of Fig. 8; Figure 11 is a cross-sectional view taken along line C-C of Figure 8; Fig. 12 (a) is a front view showing a state in which the buckle of the present embodiment is obliquely inserted, and Fig. 12 (b) is a front view showing a partial break of the socket. Fig. 13 (a) is a front view showing a state in which the buckle of the present embodiment is obliquely inserted, and Fig. 13 (b) is a front view showing a partial break of the socket.

10: buckle 12: plug 14: socket 20: leg portion 20a: front end portion 20b: base end portion 22: engaging projection 22a: locking step portion 24, 42: belt insertion portion 24a, 24b, 42a: with insertion Hole 26: operation portion 26a: front end portion 28 of operation portion: rib portion 30: thin portion 31: stopper portion 32: guide portion 34: first rod 35: second rod 36: bridge portion 40: fitting portion 40a : insertion port 44 : connecting rod 45 : upper surface portion 45 a : covering portion 46 : lower surface portion 47 : upper side wall portion 48 : lower side wall portion 50 : slit 55 : connecting portion 56 : engaged portion

Claims (7)

A buckle comprising: a plug (12) and a socket (14) that can be coupled to each other and disconnected and attached to a predetermined member, wherein the plug (12) includes a pair of legs (20), A pair of the leg portions (20) are respectively formed with engaging projections (22) at positions close to the front end portion (20a), and a pair of the center portions of the pair of the leg portions (20) are centered The mutually symmetrical positions of the feet (20) and the side edges of the sides of the center line respectively include a guiding portion (32) having a thickness in the front and back directions and including from the a rib (28) in which the engaging projection (22) continuously extends, the socket (14) comprising: an upper surface portion (45) and a lower surface forming a receiving space (52) into which the leg portion (20) is inserted a portion (46) and a pair of upper side wall portions (47) and a pair of lower portions which are disposed on both side edges of the upper surface portion (45) and the lower surface portion (46) and which face each other a side wall portion (48) between a pair of the upper side wall portions (47) and a pair of the lower side wall portions (48) Provided in a pair of slits (50) formed in a direction from which the insertion opening (40a) of the accommodating space (52) is inserted into the leg portion (20), the guiding The portion (32) abuts against the upper side wall portion (47) and/or the lower side wall portion (48) and cannot be inserted into the slit (50). The buckle according to claim 1, wherein the guide portion (32) has a dimension in the front and back directions that is larger than a dimension in the front and back directions of the slit (50). The buckle according to claim 1, wherein a belt insertion portion (24) is provided at a base end portion (20b) of the leg portion (20), and the belt insertion portion (24) includes a first portion. A rod (34) and a second rod (35) extending from both ends of the second rod (35). The buckle according to claim 3, wherein the pair of the leg portions (20) are connected to the base end portion (20b) by a U-shaped bridge portion (36). The buckle according to claim 1, wherein one end of the rib (28) is located at the engaging projection (22) and extends toward a base end portion (20b) side of the leg portion (20). a stopper portion (31) is provided at the other end of the rib (28), and the stopper portion (31) is in a state where the plug (12) is inserted into the socket (14). The upper side wall portion (47) and/or the lower side wall portion (48) are in contact with each other. The buckle according to claim 1, wherein a pair of the upper side wall portion (47) and the inner wall surface of the pair of the lower side wall portions (48) in the accommodating space (52) serve as an insertion chamber The guiding surface (54) abutting against the leg portion (20) is provided, and the shape of the guiding portion (32) formed on the pair of the leg portions (20) is identical to the guiding surface (54). The way is formed. The buckle according to claim 5, wherein a pair of the upper side wall portions (47) in the receiving space (52) and an inner wall surface of the pair of the lower side wall portions (48) are along A pair of the leg portions (20) are formed in such a manner that the interval between them is narrowed.