JP2014202314A - Locking bolt, fastener using the same and manufacturing method of locking bolt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bolt or a fastener which can be manufactured at a low cost and can simplify the operation when fastening a plurality of members to be fastened at a work site.SOLUTION: A locking bolt B1 has a bolt main body 1 and an elastic member 11. The bolt main body 1 has a bolt shaft part 3 formed of a male screw part 4 on an outer circumferential surface of the bolt shaft part. A top end groove part 7 is formed on a top end surface of the bolt shaft part 3 and, meanwhile, outer circumferential surface groove parts 8, 9 of which the top end parts are connected to an end part of the top end groove part 7 are formed on an outer circumferential surface of the bolt shaft part 3. The elastic member 11 includes a base part 12 fit into the top end groove part 7 and leg parts 13, 14 which have such a shape as to be connected to an end part of the base part 12 and be housed in the outer circumferential surface groove parts 8, 9. The leg part 13 has such a shape as to be partially exposed to an external part from the outer circumferential surface groove parts 8, 9 in such a state that an external force is not operated to the leg part 13.

Description

  The present invention relates to a locking bolt including a bolt body and an elastic member for preventing the bolt body from loosening, a fastener including a locking bolt and a nut, and a method of manufacturing the locking bolt. is there.

  Generally, a bolt is widely used as a fastener for detachably coupling a plurality of members. Specifically, for example, after forming holes through which bolts can be inserted into a plurality of members (hereinafter referred to as “fastened members”), after inserting the bolts into these holes, A plurality of members to be fastened can be detachably coupled by screwing and tightening nuts to the bolts. Moreover, after forming a female thread part in the hole part of one to-be-fastened member (henceforth "the front end side to-be-fastened member") located in the most bolt front side among several to-be-fastened members, without using a nut. A plurality of members to be fastened can be detachably coupled by screwing the male screw portion of the bolt into the female screw portion of the tip side fastened member and tightening with the other fastened member sandwiched therebetween.

  However, in this type of bolt, when a plurality of members to be fastened are joined and vibration or other continuous external force is applied to the bolt for a long period of time, it is fastened between the bolt and the nut or the bolt and the tip. The fastening between the side fastened members may be loosened and the fastening force of the bolts may be reduced, or the fastening may be completely loosened and the bolts or nuts may fall off the fastened members.

  In view of this, various bolts or fasteners having a loosening prevention structure for preventing looseness from occurring in the fastening between the bolt and the nut or the fastening between the bolt and the front side fastening member have been proposed. Specifically, for example, a bolt having two types of male screw portions formed on the outer peripheral surface, a tightening nut that is screwed with one male screw portion of the bolt, and a locking nut that is screwed with the other male screw portion of the bolt There has been proposed a fastener that prevents loosening in the fastening between the bolt and the tightening nut with a locking nut (see, for example, Patent Document 1).

  Further, after forming a cone-shaped bottomed space portion and a slit at the tip of the bolt, the bolt and the nut are screwed together, or the bolt and the tip-side fastened member are screwed together. After fastening the member to be fastened, the auxiliary bolt is screwed into the tip of the bolt to push the diameter-expanding member into the bottomed space to increase the diameter of the bolt, or between the bolt and the nut, or the bolt and the tip There has been proposed a loosening prevention bolt that prevents loosening from occurring in the fastening with the side fastened member (see Patent Document 2).

JP 2003-184848 A JP 2012-137174 A

  However, for example, the conventional bolts or fasteners having the loosening prevention structure disclosed in Patent Documents 1 and 2 have a relatively complicated structure and require a relatively advanced processing technique for the production. There is a problem that the production cost is high. In addition, there is a problem that fastening work when fastening a plurality of members to be fastened at the work site is relatively complicated. The present invention has been made in order to solve the above-described conventional problems, and can be manufactured at low cost, and can be easily tightened when fastening a plurality of members to be fastened at a work site. An object to be solved is to provide a bolt or a fastener having a prevention structure.

  The locking bolt according to the present invention made to solve the above problems includes a bolt main body and an elastic member. Here, the bolt main body has a bolt shaft portion in which a male screw portion is formed on the outer peripheral surface. A front end groove portion is formed on the front end surface of the bolt shaft portion, and an outer peripheral surface groove portion is formed on the outer peripheral surface of the bolt shaft portion so that the front end portion is connected to the end portion of the front end groove portion. On the other hand, the elastic member has a base portion fitted in the tip groove portion and an elastically deformable leg portion having a shape that is connected to the end portion of the base portion and can be accommodated in the outer peripheral surface groove portion. The leg portion has a shape that is exposed (protruded) to the outside at least partially from the outer peripheral surface groove portion when no external force is applied to the leg portion.

  In the locking bolt according to the present invention, it is preferable that two outer peripheral groove portions and two leg portions are provided. In this case, the tip groove portion is a groove extending linearly in the diameter direction of the bolt shaft portion, and the two outer peripheral surface groove portions are grooves extending linearly in the longitudinal direction of the bolt shaft portion, while each leg portion is 2 in length. It is preferable to have a shape that can be accommodated in a corresponding one of the outer peripheral surface groove portions. Each of the two leg portions has a shape that inclines and extends so as to be spaced apart from the connecting portion with the end portion of the base portion toward the tip end of the leg portion when no external force is applied to the leg portion. Is preferred. In the locking bolt according to the present invention, the lengths of the two leg portions may be different from each other.

  A fastener for releasably connecting a plurality of members to be fastened according to the present invention includes any one of the locking bolts according to the present invention, and a nut that is screwed into a male thread portion of the locking bolt. It is characterized by having.

  According to one aspect of the present invention, there is provided a method for assembling a locking bolt (an assembling method) in which a base is formed so that the widthwise dimension of the base is the same as or slightly larger than the width of the tip groove. The base portion is fitted to the tip groove portion in such a posture that the portion can be accommodated in the outer peripheral groove portion (the bolt main body and the elastic member are fixed). According to another aspect of the present invention, a locking bolt manufacturing method (assembling method) includes: a base portion formed so that a dimension in the width direction of the base portion is slightly larger than a width of a tip groove portion; The base groove is fitted into the tip groove in a posture capable of being accommodated in the outer peripheral groove, thereby fitting the tip groove and the base (fixing the bolt body and the elastic member). In addition, a method for manufacturing a locking bolt according to still another aspect of the present invention (an assembling method) includes the step of forming the base portion so that the dimension in the width direction of the base portion is smaller than the width of the tip groove portion. The base part is accommodated in the tip groove part in such a posture that the part can be accommodated in the outer peripheral groove part, and the tip groove part and the base part are fitted by caulking the tip part of the bolt shaft part so that the width of the tip groove part is narrowed. (The bolt body and the elastic member are fixed).

  The locking bolt according to the present invention includes a bolt body having a simple structure in which a tip groove portion is formed at a tip portion of a bolt shaft portion and a groove portion is formed on an outer peripheral surface of the bolt shaft portion, a tip groove portion and an outer peripheral surface groove portion. For example, it is constituted by an elastic member having a simple structure of a substantially “U” shape in which both end portions are slightly expanded from each other. Therefore, the locking bolt according to the present invention or the fastener according to the present invention including the locking bolt has a very simple structure compared to the conventional locking bolt or the fastener, and its manufacture is not much. Does not require advanced processing technology. For this reason, the locking bolt or fastener can be manufactured at low cost.

  In addition, the locking bolt according to the present invention can be assembled by a simple operation of fitting the elastic member to the tip groove portion of the bolt shaft portion of the locking bolt at the work site where the fastened member is fastened. Therefore, according to the locking bolt according to the invention or the fastener including the locking bolt, a plurality of fastened members can be fastened quickly and easily.

  According to the method of manufacturing the locking bolt according to the present invention, in the work site for fastening the member to be fastened, a simple operation of simply fitting the base portion of the elastic member to the tip groove portion of the bolt shaft portion of the bolt body, The bolt main body and the elastic member can be easily assembled by simply press-fitting into the tip groove, or by simply crimping the tip of the bolt shaft portion so that the width of the tip groove is reduced by accommodating the base in the tip groove. Can be fixed. For this reason, a to-be-fastened member can be fastened easily and easily at a work site.

(A) is the front view which looked at the volt | bolt main body which comprises the locking bolt concerning Embodiment 1 of this invention from the volt | bolt front end side, (b)-(d) is a volt | bolt main body shown to (a) from a different side. It is the side view seen, (e) is a perspective view of the volt | bolt main body shown to (a). (A) is a front view from the base part side which shows the elastic member which comprises the locking bolt which concerns on Embodiment 1 of this invention, (b) is a side view of the elastic member shown to (a). (A) is a front view of the nut screwed together with the locking bolt according to Embodiment 1 of the present invention, (b) is a side view of the nut shown in (a), and (c) is in (a). It is a perspective view of the nut shown. (A) is the front view which looked at the locking bolt which concerns on Embodiment 1 of this invention in the state which assembled | attached the elastic member to the volt | bolt main body from the bolt front end side, (b) is the side surface of the locking bolt shown to (a). It is a figure, (c) is the sectional view on the AA line of the locking bolt shown to (a), (d) is a perspective view of the locking bolt shown to (a). (A) is the front view which looked at the fastener which consists of the locking bolt which concerns on Embodiment 1 of this invention, and the nut screwed together with this locking bolt from the bolt front end side, (b) is (a). It is a side view of the fastener shown to (c), (c) is a BB sectional drawing of the fastener shown to (a), (d) is a perspective view of the fastener shown to (a). (A) is the front view which looked at the fastener which consists of the locking bolt which concerns on Embodiment 1 of this invention, and the nut screwed together with this locking bolt from the bolt front end side, (b) is (a). It is a side view of the fastener shown to (c), CC sectional view of the fastener shown to (a), (d) is a perspective view of the fastener shown to (a). (A) is the front view which looked at the volt | bolt main body which comprises the locking bolt concerning Embodiment 2 of this invention from the volt | bolt front end side, (b)-(d) is a volt | bolt main body shown to (a) from a different side surface. It is the side view seen, (e) is a perspective view of the volt | bolt main body shown to (a). (A) is a front view from the base part side of the elastic member which comprises the locking bolt which concerns on Embodiment 2 of this invention, (b) is a side view of the elastic member shown to (a). (A) is the front view which looked at the locking bolt which concerns on Embodiment 2 of this invention in the state which assembled | attached the elastic member to the volt | bolt main body from the bolt front end side, (b)-(d) is the looseness shown to (a). It is the side view which looked at a stop bolt from a different side. (A) is DD sectional drawing of the locking bolt shown to Fig.9 (a), (b) is a perspective view of the locking bolt shown to Fig.9 (a). (A) is the front view which looked at the fastener consisting of the locking bolt which concerns on Embodiment 2 of this invention, and the nut screwed together with this locking bolt from the bolt front end side, (b)-(d) FIG. 3 is a side view of the fastener shown in FIG. (A) is the EE sectional view taken on the line of the fastener shown to Fig.11 (a), (b) is a perspective view of the fastener shown to Fig.11 (a).

(Embodiment 1)
Hereinafter, with reference to FIGS. 1 to 6, the locking bolt according to the first embodiment of the present invention, the fastener provided with the locking bolt, and the method for manufacturing or assembling the locking bolt are specifically described. Explained. In the following, for convenience, with respect to the longitudinal direction of the bolt body, the end of the bolt body on which the bolt head portion is formed is referred to as a `` base end '', and the end on which the bolt head portion is not formed is referred to as `` The tip.

  As shown in FIGS. 1 (a) to 1 (e), a bolt main body 1 that is integrally formed of a metal, for example, an iron-based alloy, that constitutes the locking bolt B1 (see FIG. 4) according to Embodiment 1 of the present invention, A bolt head portion 2 and a bolt shaft portion 3 are provided. A male screw portion 4 is formed on the outer peripheral surface in the region on the tip side of the bolt shaft portion 3. In addition, a cylindrical non-threaded portion 5 in which no screw is formed is provided in a region on the proximal end side of the bolt shaft portion 3. In addition, a substantially tapered transition portion 6 or a connecting portion is provided at a boundary portion between the male screw portion 4 and the non-screw portion 5. Note that the male screw portion 4 may be formed on the entire outer peripheral surface of the bolt shaft portion 3 without providing the non-screw portion 5 and the transition portion 6.

  The front end surface of the bolt shaft portion 3 extends linearly in the diameter direction of the bolt shaft portion 3, and both ends thereof are opened to the outer peripheral surface of the bolt shaft portion 3 or outer peripheral surface groove portions 8 and 9 described later. A leading end groove portion 7 is formed. The tip groove portion 7 has a rounded concave bottom, for example, a concave bottom having a semicircular or semi-circular cross section. The bottom portion of the tip groove portion 7 is not limited to the concave shape having such a round shape, but has other shapes, for example, a flat bottom surface, or a triangular, square or other polygonal cross section. It may be.

  In the region where the male threaded portion 4 of the bolt shaft portion 3 is formed, the outer peripheral surface of the bolt shaft portion 3 is linear in the longitudinal direction of the bolt shaft portion 3, that is, in the direction parallel to the center line of the bolt shaft portion 3. A first outer peripheral surface groove portion 8 and a second outer peripheral surface groove portion 9 extending in a shape and having the same length are formed. The lengths of the first and second outer peripheral surface groove portions 8 and 9 are set to a length corresponding to 2 to 10 pitches of the male screw portion 4, for example, and preferably 4 to 6 pitches. In addition, the length of the 1st and 2nd outer peripheral surface groove parts 8 and 9 is not necessarily limited to such a range, It may be longer than this and may be short.

  The first and second outer peripheral surface groove portions 8 and 9 have a rounded concave bottom, for example, a concave bottom having a semicircular or semi-circular cross section. The bottom portions of the first and second outer peripheral groove portions 8 and 9 are not limited to the concave shape having such a roundness, but have other shapes, for example, those having a flat bottom surface or a cross section. May be triangular, square or other polygonal.

  The first and second outer peripheral groove portions 8 and 9 are formed around the center line of the bolt shaft portion 3 at positions separated from each other by a central angle of 180 °. The first outer peripheral groove 8 is formed so that the tip thereof is connected (opened) to one end of the tip groove 7. That is, the distal end portion of the first outer peripheral groove portion 8 is open to the distal end groove portion 7 or the distal end surface of the bolt shaft portion 3. Further, the second outer peripheral surface groove portion 9 is formed such that the tip end portion thereof is connected (opened) to the other end portion of the tip groove portion 7. That is, the distal end portion of the second outer peripheral surface groove portion 9 is opened to the distal end groove portion 7 or the distal end surface of the bolt shaft portion 3.

  As shown in FIGS. 2A and 2B, the elastically deformable elastic member 11 that is integrally formed of a metal, for example, an iron-based alloy, that constitutes the locking bolt B1 (see FIG. 4) according to the first embodiment, A linear base 12, a linear first leg 13 connected to one end of the base 12, and a linear second leg 14 connected to the other end. Have. The elastic member 11 is curved at the transition portions 15 and 16 or the connection portion between the base portion 12 and the first or second leg portions 13 and 14.

  The first and second leg portions 13 and 14 are connected to the corresponding end portions of the base portion 12 in a state where no external force is applied to the leg portions 13 and 14, that is, in a state where the leg portions 13 and 14 are not elastically deformed. And extending toward the distal end (the end opposite to the base 12) so as to be spaced apart from each other. That is, in the state where the external force is not acting on the first and second legs 13 and 14, the elastic member 11 is spaced from each other toward the distal ends of the first and second legs 13 and 14. Is formed so as to have a substantially “U” -shaped shape.

  The base portion 12 of the elastic member 11 is formed so as to have a shape or size that can be fitted into the tip groove portion 7 of the bolt body 1. For example, when the operator fixes the elastic member 11 to the bolt body 1 by manually fitting the base portion 12 into the tip groove portion 7, the width of the base portion 12, that is, the thickness of the base portion 12 is the width of the tip groove portion 7. It is formed to be the same or slightly larger.

  When the base 12 is fitted into the tip groove 7 by press-fitting the base 12 into the tip groove 7 using an appropriate tool and the elastic member 11 is fixed to the bolt body 1, the base 12 is The size, that is, the thickness is formed to be slightly larger than the width of the tip groove portion 7. Specifically, the base portion 12 is appropriately plastically deformed when pressed into the tip groove portion 7, and is held in the tip groove portion 7 while maintaining an appropriate pressing force or contact force between the base portion 12 and the tip groove portion 7. Shaped or dimensioned to be accommodated.

  Further, for example, by using a jig or the like to crimp the distal end portion of the bolt shaft portion 3 so that the width of the distal end groove portion 7 is narrowed, the base portion 12 is fitted into the distal end groove portion 7 and the elastic member 11 is attached to the bolt body 1. In the case of fixing, the base portion 12 is formed so that the dimension in the width direction, that is, the thickness is slightly smaller than the width of the tip groove portion 7. Specifically, the base portion 12 has an appropriate pressing force or abutting force between the base portion 12 and the tip groove portion 7 because the bolt shaft portion 3 is appropriately plastically deformed when the tip portion of the bolt shaft portion 3 is caulked. Is formed in a shape or dimension so as to be accommodated in the distal end groove portion 7 while holding.

  On the other hand, the first and second leg portions 13 and 14 of the elastic member 11 have shapes or dimensions that can be accommodated in the first and second outer peripheral groove portions 8 and 9 of the bolt body 1, respectively. Is formed. Thus, the first and second leg portions 13 and 14 are at least far from each other when no external force is applied to the leg portions 13 and 14 in a state where the base portion 12 is fitted to the tip groove portion 7. A portion on the distal end side has a shape or dimension that is exposed (protruded) to the outside from the first and second outer peripheral groove portions 8 and 9.

  When the diametrically inward force of the bolt shaft portion 3 acts on the first and second legs 13 and 14, the first and second legs 13 and 14 have their distal ends connected to each other. The first and second leg portions 13 and 14 are elastically deformed so as to approach each other, that is, the first and second outer peripheral surface groove portions 8 and 9 are respectively accommodated. The elastic member 11 returns to its original shape due to its elasticity when no force acts on the first and second leg portions 13 and 14.

  Cross section of the base 12 or the first and second legs 13 and 14 of the elastic member 11, that is, a section cut along a plane perpendicular to the longitudinal axis of the base 12 or the first or second legs 13 and 14. The shape of is according to the shape of the cross-section cut along the plane perpendicular to the longitudinal axis of the longitudinal groove of the tip groove 7 or the first or second outer peripheral groove 8, 9, that is, the groove 7, 8, 9, It is preferably set to engage with or correspond to this. The cross section of the base 12 or the first and second legs 13 and 14 may be a circle, an ellipse (elliptical) triangle, a quadrangle, other polygons, or other shapes. Also good.

  3 (a) to 3 (c) show a nut 18 that can be screwed with the male thread portion 4 of the bolt body 1 shown in FIGS. 1 (a) to 1 (e). A nut body 19 having a hexagonal outer shape of the nut 18 is formed with a female screw portion 20. The nut 18 constitutes the fastener according to the first embodiment with the locking bolt B1.

  As shown in FIGS. 4A to 4D, the locking bolt B1 according to the first embodiment is the same as the elastic member 11 shown in FIGS. 2A and 2B in FIGS. It is manufactured by assembling to the bolt body 1 shown. In this case, the base portion 12 of the elastic member 11 is formed in the tip groove portion 7 in such a posture that the first and second leg portions 13 and 14 can be accommodated in the first and second outer peripheral surface groove portions 8 and 9, respectively. The elastic member 11 is fixed to the bolt body 1 by fitting.

  When manufacturing or assembling the locking bolt B1, the base portion 12 is arranged so that there is almost no backlash in the circumferential direction of the bolt shaft portion 3 between the elastic member 11 and the bolt body 1, that is, the elastic member 11. It is necessary to firmly fit the tip groove portion 7 so that relative rotation (rotation) around the center line of the bolt shaft portion 3 hardly occurs between the bolt body 1 and the bolt body 1. If such rattling or relative rotation is large, after fastening a plurality of members to be fastened using the locking bolt B1, the locking bolt B1 rotates in the loosening direction, and the locking bolt B1 is tightened. There is a risk of loosening due to reduced force.

  Hereinafter, a specific example of a method for assembling or manufacturing the locking bolt B1 will be described. When the operator manually attaches the elastic member 11 to the bolt main body 1 without using a special tool, the elastic member 11 having a width direction dimension of the base portion 12 that is the same as or slightly larger than the width of the tip groove portion 7 is used. . Then, the worker holds the elastic member 11 in a posture in which the first and second leg portions 13 and 14 can be accommodated in the first and second outer peripheral groove portions 8 and 9, respectively, at the work site. However, if the base portion 12 of the elastic member 11 is manually inserted into the tip groove portion 7 of the bolt body 1, the locking bolt B1 is completed. According to this method, the locking bolt B1 can be assembled by a very simple operation.

  In the locking bolt B1 assembled in this way, as is apparent from FIGS. 4B and 4C, the distal end portions of the first and second legs 13 and 14 are respectively the first end. Further, the second outer peripheral surface groove portions 8 and 9 are exposed or protruded radially outward of the bolt shaft portion 3. The distance a between the distal ends of the first and second legs 13 and 14 (see FIG. 2B) is preferably at least larger than the inner diameter (valley diameter) of the female thread 20 of the nut 18. Is set.

  If the operator needs a stronger coupling force between the base portion 12 of the elastic member 11 and the tip groove portion 7 of the bolt body 1 than if the operator inserts the base portion 12 into the tip groove portion 7 by hand, an appropriate tool is used. By using the base 12 to press fit into the tip groove 7, the base 12 is fitted into the tip groove 7 and the elastic member 11 is fixed to the bolt body 1. In this case, the dimension of the base portion 12 in the width direction is set to be slightly larger than the width of the tip groove portion 7. According to the assembling method or the manufacturing method of the locking bolt B1, the base portion 12 is appropriately plastically deformed when pressed into the tip groove portion 7, and a strong coupling force is generated between the base portion 12 and the tip groove portion 7, The elastic member 11 can be firmly fixed to the bolt body 1.

  When a stronger coupling force is required between the base 12 of the elastic member 11 and the tip groove 7 of the bolt body 1 than when the base 12 is press-fitted into the tip groove 7, the base 12 is accommodated in the tip groove 7. Then, by using an appropriate jig or the like, the base portion 12 is fitted to the tip groove portion 7 by caulking the tip portion of the bolt shaft portion 3 so that the width of the tip groove portion 7 is narrowed, and the elastic member 11 is attached to the bolt body. Fix to 1. In this case, the dimension in the width direction of the base portion 12 is set to be slightly smaller than the width of the tip groove portion 7. According to the assembling method or the manufacturing method of the locking bolt B1, the bolt shaft portion 3 is plastically deformed when the tip portion of the bolt shaft portion 3 is caulked, and is very strong between the base portion 12 and the tip groove portion 7. A coupling force is generated, and the elastic member 11 can be fixed to the bolt body 1 more firmly.

  5A to 5D, the nut 18 is screwed into the locking bolt B1, the female screw portion 20 of the nut 18 and the male screw portion 4 of the locking bolt B1 are screwed, and the nut 18 is an elastic member. 11 is engaged. In this state, the fastening of the locking bolt B1 and the nut 18 is completed. In this case, as shown in FIGS. 5A to 5D, the distal end portions (generally half portions) of the first and second leg portions 13 and 14 of the elastic member 11 are respectively nuts 18. The female screw portion 20 (thread) is in contact with the female screw portion 20 and is elastically deformed inward in the radial direction of the bolt shaft portion 3 by the female screw portion 20. For this reason, the elastic force of the first and second leg portions 13 and 14 causes the first and second leg portions 13 and 14 and the female screw portion 20 (threads) to interfere with each other. Frictional force acts. This frictional force prevents the fastening between the nut 18 and the locking bolt B1 from being loosened.

  The loosening prevention action between the nut 18 and the locking bolt B1 occurs regardless of whether a fastened member exists between the bolt head portion 2 and the nut 18. Therefore, although not shown, when a plurality of fastened members are detachably coupled with the locking bolts B1 and the nuts 18, the bolt shaft portion 3 passes through the hole formed in the fastened member. If a plurality of members to be fastened are sandwiched between the bolt bolt head portion 2 and the nut 18 and the nut 18 is screwed into the locking bolt B1 and tightened, loosening will occur between the nut 18 and the locking bolt B1. It is prevented from occurring.

  6 (a) to 6 (d), after the nut 18 is screwed into the locking bolt B1, and the female threaded portion 20 of the nut 18 and the male threaded portion 4 of the locking bolt B1 are screwed together, FIG. The nut 18 is further tightened and moved to the proximal end side from the state shown in FIG. 4D, and the nut 18 is stopped from being tightened when the nut 18 is not engaged with the elastic member 11. In this state, as shown in FIGS. 6A to 6D, the first and second leg portions 13 and 14 of the elastic member 11 do not engage with the female screw portion 20 of the nut 18. Accordingly, the distal end side portions of the first and second leg portions 13 and 14 are respectively in the radial direction of the bolt shaft portion 3 from the first and second outer peripheral groove portions 8 and 9. It is exposed or protrudes outside.

  Thereafter, for example, a continuous force such as vibration is applied to the nut 18 and the locking bolt B1 over a long period of time, and the nut 18 or the locking bolt B1 rotates to the loose side, causing a looseness between them, and the nut 18 is at the tip. May try to move to the side. However, in this case, the end face on the tip side of the nut 18 interferes with the distal ends of the first and second legs 13, 14, and the movement of the nut 18 toward the tip side is the first and second legs 13. , 14. For this reason, the nut 18 cannot rotate to the loose side, thereby preventing the nut 18 from falling off the loosening prevention bolt B1.

  At this time, a force in a direction for separating the elastic member 11 from the bolt body 1 is applied from the nut 18 to the elastic member 11. 6A to 6D, when the locking bolt B1 according to the first embodiment is used, the elastic member 11 and the locking bolt B1 are used, and the base 12 is connected to the tip groove portion 7. It is preferable that the bolt shaft 3 is joined by press-fitting, and it is more preferred that the bolt shaft portion 3 is joined by caulking the tip groove portion 7 in the direction of narrowing the tip groove portion 7.

  The fastener constituted by the locking bolt B1 or the locking bolt B1 and the nut 18 according to the first embodiment has a very simple structure as compared with the conventional locking bolt or fastener, and its manufacture. It does not require very advanced processing technology. For this reason, the locking bolt B1 or the fastener can be manufactured at a low cost. Further, according to the manufacturing method or the assembling method of the locking bolt B1 according to the first embodiment, the base portion 12 of the elastic member 11 is fitted to the tip groove portion 7 of the locking bolt B1 at the work site where the fastened member is fastened. Since it can assemble | attach by only a simple operation | work, the fastening of several to-be-fastened members can be performed quickly and easily.

  By the way, generally, when a plurality of members to be fastened are fastened to each other using bolts, after some or all of the members to be fastened are coated, these members to be fastened may be fastened using bolts. For example, in the assembly process of a car body of an automobile, first, a nut is welded to a plate-like member that is a component of the car body, then coating is applied to the plate-like member, and then the nut and bolt are screwed together. is there. In this case, when the plate-like member is coated, the paint may adhere to the valleys between the threads of the female threaded portion of the nut or the flanks of the thread.

  In this way, when the nut and bolt on which the paint adheres to the female screw part and the coating film is formed are screwed together, the paint adhering to the female screw part causes a gap between the female screw part of the nut and the male screw part of the bolt. There is a possibility that the clearance becomes abnormally small, the frictional force between the female screw portion and the male screw portion increases, and a tightening abnormality may occur. When such a tightening abnormality occurs, a sufficient tightening axial force cannot be obtained between the bolt and the nut, and the bolt and the nut cannot be securely or securely fastened. In addition, without using a nut, after forming a female screw part in the hole of the tip side fastened member, the female screw part of the tip side fastened member and the male screw part of the bolt are screwed together and tightened. Similar problems arise when fastening members.

  However, when a plurality of members to be fastened are fastened by using the fastener constituted by the locking bolt B1 and the nut 18 according to the present invention, the nut 18 in which the paint is attached to the female screw portion 20 and a coating film is formed. And the locking bolt B1 are screwed together, the coating film is peeled off by the distal ends of the first and second legs 13 and 14 of the elastic member 11, and the peeled paint or coating film is removed to the outside. The In this way, the paint or the coating film can be removed from the internal thread portion of the nut 18, so that the nut 18 and the locking bolt B <b> 1 can be screwed together and tightened firmly with an appropriate tightening force. In addition, without using the nut 18, after forming a female thread part in the hole of a front side fastening member, the female thread part of the front side fastening member and the male thread part 4 of the locking bolt B1 are screwed together and tightened. This is the same when fastening the fastened member.

(Embodiment 2)
Hereinafter, with reference to FIGS. 7 to 12, the locking bolt according to the second embodiment of the present invention, the fastener using the locking bolt, and the method for manufacturing or assembling the locking bolt are specifically described. Explained. However, the method for manufacturing the locking bolt, the fastener, and the locking bolt according to the second embodiment has many common points with the method for manufacturing the locking bolt, the fastener, and the locking bolt according to the first embodiment. Therefore, in order to avoid duplication of explanation, points different from the first embodiment will be mainly described below. In addition, in the component of the locking bolt B2 or the fastener according to Embodiment 2 shown in FIGS. 7 to 12, the component is substantially the same as the component of the locking bolt B1 or the fastener according to Embodiment 1 shown in FIGS. Those having the same configuration and function are denoted by the same reference numerals as in the first embodiment.

  As shown in FIGS. 7A to 7E, in the bolt body 21 according to the second embodiment, the length of the first outer peripheral groove portion 24 and the length of the second outer peripheral groove portion 25 are different from each other. Specifically, the length of the first outer peripheral groove 24 is substantially the same as that of the bolt body 1 according to the first embodiment, but the length of the second outer peripheral groove 25 is the first outer peripheral groove. The length is longer than 24 (for example, a length corresponding to 2 to 4 pitches of the male screw portion 4). Of course, the length of the first outer peripheral groove 24 may not be the same as that of the bolt body 1 according to the first embodiment. Other configurations or functions of the bolt body 21 according to the second embodiment are substantially the same as those of the bolt body 1 according to the first embodiment.

  As shown in FIGS. 8A and 8B, in the elastic member 31 according to the second embodiment, the length of the first leg portion 33 and the length of the second leg portion 34 are different from each other. Specifically, the length of the first leg portion 33 is set to correspond to the length of the first outer peripheral surface groove portion 24, and the length of the second leg portion 34 is set to the second outer peripheral surface groove portion 25. It is set to correspond to the length of. Note that the lengths of the first and second leg portions 33 and 34 are accommodated in the first and second outer peripheral surface groove portions 24 and 25, respectively, so that the first and second outer peripheral surface groove portions 24 and 25 are accommodated in the first and second outer peripheral surface groove portions 24 and 25, respectively. It is set to be slightly shorter than the length of. Other configurations or functions of the elastic member 31 according to the second embodiment are substantially the same as those of the elastic member 11 according to the first embodiment.

  FIGS. 9A to 9D and FIGS. 10A and 10B show a locking bolt B2 according to the second embodiment. The method for manufacturing or assembling the locking bolt B2 according to the second embodiment is substantially the same as the method for manufacturing or mounting the locking bolt B1 according to the first embodiment.

  11 (a) to 11 (d) and FIGS. 12 (a) and 12 (b), the nut 18 is screwed into the locking bolt B2 according to the second embodiment, and the female screw portion 20 of the nut 18 and the locking bolt B2 are connected. The state where the male screw portion 4 is screwed is shown. Here, the nut 18 is tightened with respect to the locking bolt B2 and once engaged with the first leg 33, and then further tightened and moved to the proximal end side, so that the nut 18 is moved to the first leg 33. Is in a state where it is no longer engaged. In this state, since the first leg portion 33 of the elastic member 31 is not engaged with the female screw portion 20 of the nut 18, the first leg portion 33 returns to its original state due to its elasticity, and the first leg A portion on the distal end side of the portion 33 is exposed or protruded from the first outer peripheral groove portion 24 to the outside in the radial direction of the bolt shaft portion 3. Accordingly, the nut 18 is prevented from falling off the locking bolt B2 as in the case where the fastener is in the state shown in FIGS. 6A to 6D in the first embodiment.

  Further, the nut 18 is in a state of being fastened to the locking bolt B2 and being engaged with the second leg 34. In this case, the distal end side portion (generally half portion) of the second leg portion 34 abuts on the female threaded portion 20 (thread) of the nut 18, and the bolted shaft portion 3 faces inward in the radial direction by the female threaded portion 20. The state is elastically deformed. For this reason, the elastic force of the second leg portion 34 causes the second leg portion 34 and the female screw portion 20 (thread) to interfere with each other, and a frictional force acts between them. This frictional force prevents loosening between the nut 18 and the locking bolt B2.

  In short, according to the locking bolt B2 or the fastener including the locking bolt according to the second embodiment, the nut 18 is moved from the locking bolt B2 to FIGS. 11 (a) to 11 (d) and FIGS. 12 (a) and 12 (b). ), The looseness prevention function and the dropout prevention function can be exhibited at the same time. Further, the locking bolt B2 according to the second embodiment or the fastener constituted by the locking bolt B2 and the nut 18 can also provide substantially the same effect as in the first embodiment.

  In the first and second embodiments, a plurality of members to be fastened are detachably coupled by screwing the nut 18 to the locking bolts B1 and B2 and tightening. However, the locking bolts B <b> 1 and B <b> 2 according to the present invention can also be used to removably couple a plurality of members to be fastened without using the nut 18. In this case, after forming the female screw portion in the hole portion of the distal-side fastened member among the plurality of fastened members, the other screwed portion is sandwiched and the female screw portion of the distal-side fastened member is loosened. A plurality of members to be fastened can be detachably coupled by screwing and tightening the male screw portions 4 of the set bolts B1 and B2.

  B1 Locking bolt according to Embodiment 1, B2 Locking bolt according to Embodiment 2, 1 Bolt body, 2 Bolt head part, 3 Bolt shaft part, 4 Male screw part, 5 Non-screw part, 6 Transition part, 7 Tip groove part , 8 First outer peripheral groove portion, 9 Second outer peripheral surface groove portion, 11 Elastic member, 12 Base portion, 13 First leg portion, 14 Second leg portion, 15 Bending portion, 16 Bending portion, 18 Nut, 19 Nut main body, 20 female thread portion, 21 bolt main body, 24 first outer peripheral surface groove portion, 25 second outer peripheral surface groove portion, 31 elastic member, 33 first leg portion, 34 second leg portion.

Claims (8)

A bolt shaft portion having a male screw portion formed on an outer peripheral surface, and a tip groove portion is formed on a tip surface of the bolt shaft portion, and a tip portion of the tip shaft groove is formed on the outer peripheral surface of the bolt shaft portion; A bolt body in which an outer peripheral surface groove portion connected to the end portion is formed;
A slack comprising an elastic member having a base inserted into the tip groove and an elastically deformable leg connected to the end of the base and capable of being accommodated in the outer peripheral groove. A set bolt,
The locking bolt according to claim 1, wherein the leg portion has a shape that is at least partially exposed to the outside from the outer peripheral groove portion when no external force is applied to the leg portion. Two outer peripheral groove portions are provided, the tip groove portion is a groove extending linearly in the diameter direction of the bolt shaft portion, and the two outer peripheral groove portions are linear in the longitudinal direction of the bolt shaft portion, respectively. While the groove extends to
The two leg portions are provided, and each leg portion has a shape that can be accommodated in one corresponding outer peripheral surface groove portion of the two outer peripheral surface groove portions. Item 2. A locking bolt according to item 1.   Each of the two leg portions has a shape extending in an inclined manner so that a distance from each other is increased from a connection portion with the end portion of the base portion toward the tip of the leg portion in a state where no external force is applied to the leg portions. The locking bolt according to claim 2, wherein the locking bolt is provided.   4. The locking bolt according to claim 2, wherein the lengths of the two legs are different from each other.   A plurality of members to be fastened are provided, comprising: the locking bolt according to any one of claims 1 to 4; and a nut that is screwed with the male screw portion of the locking bolt. Fasteners for joining together. It is a manufacturing method of the locking bolt according to any one of claims 1 to 4,
After forming the base so that the widthwise dimension of the base is the same as the width of the tip groove,
A method of manufacturing a locking bolt, wherein the base portion is fitted to the tip groove portion in such a posture that the leg portion can be accommodated in the outer peripheral surface groove portion. It is a manufacturing method of the locking bolt according to any one of claims 1 to 4,
After forming the base so that the dimension in the width direction of the base is larger than the width of the tip groove,
A locking bolt according to claim 1, wherein the tip groove portion and the base portion are fitted together by press-fitting the base portion into the tip groove portion in a posture in which the leg portion can be accommodated in the outer peripheral surface groove portion. Production method. It is a manufacturing method of the locking bolt according to any one of claims 1 to 4,
After forming the base so that the dimension in the width direction of the base is smaller than the width of the tip groove,
By accommodating the base portion in the tip groove portion in a posture in which the leg portion can be accommodated in the outer peripheral surface groove portion, and caulking the tip portion of the bolt shaft portion so that the width of the tip groove portion is narrowed, A method of manufacturing a locking bolt comprising fitting the tip groove and the base.

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