JP2023070805A - Bolt with engagement part - Google Patents

Abstract

To provide a fastening bolt that can be prevented from being loosened and can be fastened only from the side of one member to be fastened.SOLUTION: A bolt 1 with an engagement part comprises: a bolt head part 2 that can be gripped and tightened with a tool; a rod-shaped bolt body 3 continuous with the bolt head part 2; a male screw part 4 provided on the tip side of the bolt body 3; a first engagement part 5 having looseness prevention convex parts 5a provided at intervals in a circumferential direction at the tip of the male screw part 4; and a second engagement part 6 having a tool engagement convex 6a further at the tip of the first engagement part 5.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to a bolt with an engaging portion having an engaging portion at the tip of a male threaded portion.

Conventionally, as this type of bolt with an engaging portion, an engaging portion having a spiral vane-shaped spring extending axially on the outer peripheral surface is provided at the tip, and a female member corresponding to this engaging portion is engaged. , is known to prevent loosening of fastened bolts and nuts (see, for example, Patent Document 1).

In addition, when fastening the materials to be fastened with bolts and nuts, the bolts and nuts temporarily fixed between the materials to be fastened can be tightened only from one side of the materials to be fastened. "Bolt" is known (see Patent Document 2).

Furthermore, a fiber-reinforced resin walkway is known, which has a small number of main girder parts and can easily secure the strength of the main girder, as disclosed in Patent Document 3.

JP-A-7-197925 Japanese Patent No. 2723493 Japanese Patent No. 6915218

There is no conventional bolt with an engaging portion that has the functions of both the bolt and nut of Patent Document 1 and the one-side bolt of Patent Document 2. In addition, there is a demand for a one-side bolt suitable for a corridor made of fiber-reinforced resin as disclosed in Patent Document 3, which can be easily tightened and does not loosen.

The present invention has been made in view of this point, and its object is to provide a fastening bolt that can be prevented from loosening and that can be fastened only from one side of a member to be fastened. That's what it is.

In order to achieve the above object, in the present invention, the second engaging portion is provided further at the tip of the first engaging portion.

Specifically, in the first invention, a bolt head that can be gripped and tightened with a tool;
a rod-shaped bolt body continuous with the bolt head;
a male screw portion on the tip side of the bolt body;
a first engaging portion having locking protrusions provided at intervals in the circumferential direction at the distal end of the male screw;
A second engaging portion having a tool engaging convex portion which is provided at the tip of the first engaging portion and engages with a fastening tool is also provided.

According to the above configuration, the anti-loosening effect is exhibited by engaging the anti-loosening protrusion of the first engaging portion with the anti-loosening portion of the anti-loosening nut. Further, by engaging the fastening tool with the tool engagement projection from the tip side and rotating it, the male screw can be screwed and fastened.

In the second invention, in the first invention,
The circumferential pitch of the locking projections is smaller than the circumferential pitch of the tool engaging projections of the second engaging portion.

According to the above configuration, by reducing the circumferential pitch of the locking portion, the locking effect is improved, and by increasing the circumferential pitch of the tool engaging projections, it is possible to easily transmit the torque of the tool. can be done.

In a third invention, in the first or second invention,
The maximum outer diameter of the first engaging portion is larger than the maximum outer diameter of the second engaging portion,
A step is provided between the first engaging portion and the second engaging portion.

According to the above configuration, by providing a step between the two engaging portions, it is possible to prevent the first engaging portion from being damaged by a tool engaged with the second engaging portion.

In a fourth invention, the bolt with an engaging portion according to any one of the first to third inventions is an integrally molded article made of reinforcing fiber resin.

According to the above configuration, it is possible to easily form a bolt having a relatively high rigidity even if it has a complicated shape. Further, the bolt with an engaging portion made of reinforced fiber resin is suitable for fastening a resin structure such as a corridor made of reinforced resin made of the same material.

In a fifth invention, in any one of the first to fourth inventions,
The maximum diameter of the first engaging portion is smaller than the maximum diameter of the male screw portion and larger than the maximum diameter of the second engaging portion.

According to the above configuration, the locking nut or the like is inserted from the second engaging portion on the tip side, and the second engaging portion is used to tighten the bolt with the engaging portion with a tool to prevent the first engaging portion from loosening. By engaging an anti-loosening part such as a nut, the anti-loosening effect can be obtained by tightening from one direction.

In a sixth invention, in any one of the first to fifth inventions,
the locking convex portion of the first engaging portion forms a projection extending in the longitudinal direction of the bolt body and arranged at regular intervals in the circumferential direction;
The second engaging portion is configured to have a polygonal cross section.

According to the above configuration, the locking effect is exhibited by the first engaging portion formed with the ridge, and the second engaging portion having a polygonal cross section facilitates tightening with a tool such as a wrench or pliers. .

In the seventh invention, in the sixth invention,
The locking convex portion of the first engaging portion is configured to be an external ratchet.

According to the above configuration, an optimum loosening prevention projection that allows rotation in the tightening direction and prevents rotation in the loosening direction can be obtained.

As described above, according to the present invention, since the second engaging portion for engaging a tool is provided further ahead of the first engaging portion for preventing loosening, it is possible to prevent loosening of the tightening bolt. Moreover, it is possible to make it possible to fasten only from one side of the fastened member.

FIG. 4 is a front view showing the power tool to which the tightening tool for the bolt with engaging portion is fixed; Fig. 10 is a side view showing the power tool to which the tightening tool for the bolt with engaging portion is fixed; The bolt with an engaging part is shown, (a) is a left side view, (b) is a front view, and (c) is a right side view. FIG. 5 is a front view showing a state in which the locking nut is fastened to the bolt with the engaging portion to prevent loosening. FIG. 5 is a front view showing a state in which the locking nut is temporarily fixed to the bolt with the engaging portion; The locking nut is shown, (a) is a left side view, (b) is a front view, and (c) is a right side view. FIG. 4 is a plan view showing a state in which a bolt with an engaging portion and a locking nut are attached to a fastening tool for a bolt with an engaging portion;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

-Configuration of bolt with engaging portion-
FIG. 3 shows a bolt 1 with an engaging portion according to an embodiment of the present invention, and the bolt 1 with an engaging portion is made of reinforcing fiber resin such as reinforcing fiber synthetic resin containing glass fiber, carbon fiber, etc. consists of an integrally molded product. Examples of synthetic resins include thermoplastic resins such as polyamide resin (PA), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), and ABS resin, and thermosetting resins such as epoxy resin and vinyl ester resin. be done. As described above, since the bolt 1 with the engaging portion is made of a reinforcing fiber resin integrally molded product, it is possible to easily mold a bolt having a relatively high rigidity even in a complicated shape.

The engaging portion-equipped bolt 1 has, for example, a hexagonal bolt head 2 that can be gripped and tightened with a tool such as a torque wrench. This may be a hexagonal head.

A bolt 1 with an engaging portion has a rod-shaped bolt body 3 that is continuous with a bolt head 2. In this embodiment, the bolt body 3 includes a cylindrical portion without unevenness and a male screw portion 4 on the tip side. and

At the tip of the male threaded portion 4, there is provided a first engaging portion 5 having locking projections 5a provided at intervals in the circumferential direction. The locking projections 5a extend in the longitudinal direction of the bolt body 3 and constitute projections arranged at regular intervals in the circumferential direction.

As shown in a partially enlarged view in FIG. 3(c), the locking protrusion 5a is composed of an external toothed ratchet wheel having a substantially triangular cross section of the same shape and size. Specifically, this external toothed ratchet has an outer meshing surface 5b included in the same imaginary plane as the axis of the bolt body 3, and an outer meshing surface 5b extending in the tightening direction of the lock nut 10 from the tip of the outer meshing surface 5b. and an outer tapered surface 5c inclined toward the outer meshing surface 5b. The external toothed ratchet provides an optimum locking protrusion 5a that allows rotation in the tightening direction and prevents rotation in the loosening direction. The locking portion 11 of the locking nut 10 fitted to the outer meshing surface 5b will be described later.

Further at the tip of the first engaging portion 5, a second engaging portion 6 having a tool engaging convex portion 6a with which the tip of an inner member 25 of a fastening tool 20 (to be described later) engages is provided. The second engaging portion 6 is, for example, a regular hexagonal column whose corners form tool engaging projections 6a. However, a triangular prism, a square prism, or the like may be used as long as the tool can be engaged. The second engaging portion 6 having a polygonal cross section can be easily tightened with a tool such as a wrench or pliers.

As shown in FIG. 3(c), the circumferential pitch P1 of the locking projections 5a corresponds to the circumferential pitch P2 of the tool engaging projections 6a of the second engaging portion 6 (that is, the distance between the vertices of the hexagonal prism). ) (P1<P2). In this way, by reducing the circumferential pitch P1 of the locking portion 11, the locking effect is improved, and by increasing the circumferential pitch P2 of the tool engaging convex portion 6a, the torque of the tool can be easily transmitted. You can do it.

As shown enlarged in FIG. 3B, the maximum outer diameter D1 of the first engaging portion 5 is larger than the maximum outer diameter D2 of the second engaging portion 6 (D1>D2). A stepped portion 7 is provided between the first engaging portion 5 and the second engaging portion 6 . Thus, by providing the stepped portion 7 between the two engaging portions 5 and 6, it is possible to prevent the first engaging portion 5 from being scratched by a tool engaged with the second engaging portion 6. It's like The size of the stepped portion 7 is not particularly limited, but if it is too small, the effect will be reduced. Further, as shown in the figure, the maximum diameter D1 of the first engaging portion is smaller than the maximum diameter D3 of the male screw portion and larger than the maximum diameter D2 of the second engaging portion (D2<D1<D3 ).

- Configuration of fastening tool for bolt with engaging portion -
As shown in FIGS. 1 and 2, in this embodiment, a dedicated fastening tool 20 is used to fasten the bolt 1 with the engaging portion described above. The fastening tool 20 of the present invention is fixed to the power tool 21 on the base end side, is arranged with a distance in the radial direction of the rotating shaft 21a of the power tool 21, and is temporarily fixed to the bolt 1 with the engaging portion on the tip end side. A cylindrical outer member 24 is provided to prevent the locking nut 10 from rotating. Specifically, the outer member 24 is fixed to the main body of the power tool 21 on the base end side and fixed to the leg mounting holes 23c of the disk-shaped flange portion 23 on the distal end side. I have. The leg portions 22 are arranged at an interval of 90° in the circumferential direction, and are sufficiently spaced from the rotating shaft 21 a of the power tool 21 in the radial direction. By attaching to the power tool 21 using the leg portion 22, even if the shape of the power tool 21 is different, relatively easy and reliable attachment becomes possible.

As shown in a partially enlarged view in FIG. 2, the outer member 24 has a regular hexagonal cross-sectional tubular shape, the base end of which is inserted into the through hole 23a of the flange portion 23, and the chamfered portion 24c of which is inserted into the through hole. It abuts on a flat surface 23b formed in 23a, and is fixed on the flat surface 23b by a fastening member or the like (not shown).

A nut through-hole 24b having a regular hexagonal cross section is provided on the distal end side of the outer member 24, and a locking nut 10, which will be described later, can be fitted into the nut through-hole 24b.

As shown in FIG. 7, an opening 24a is provided on, for example, the upper surface side of the outer member 24 to expose the tip side of the locking nut 10 and the bolt 1 with the engaging portion, which are locked by the outer member 24. . Note that such an opening may be provided on the lower surface side as well. Workability is improved by providing it also on the lower surface side.

An inner member 25 is arranged inside the outer member 24 with a space therebetween in the radial direction. As shown in a partially enlarged view in FIG. 2, the inner member 25 has, for example, a tubular shape with a regular hexagonal cross section, and a hexagonal engaged hole 25a is formed therethrough. The base end side of the engaged hole 25a is integrally fixed to the rotating shaft 21a, and the distal end side thereof engages with the second engaging portion 6 at the distal end of the bolt 1 with an engaging portion.

The outer member 24 and the inner member 25 may be coated, plated, or the like for corrosion protection.

As shown in FIG. 6, the locking nut 10 has a female threaded portion 12 on the inner peripheral surface on the proximal end side to be screwed into the male threaded portion 4 of the bolt with an engaging portion 1, and an engaging threaded portion on the distal end side. A divided portion 13 having an anti-loosening portion 11 that engages with the anti-loosening convex portion 5a of the first engaging portion 5 of the joint bolt 1 is formed integrally. In this embodiment, the anti-loosening portion 11 is composed of an inner ratchet that fits into the anti-loosening convex portion 5 a (outer ratchet) of the first engaging portion 5 . The locking nut 10 is, for example, the same reinforced fiber resin integrally molded product as the bolt with engaging portion 1 .

As shown in a partially enlarged view in FIG. 6(c), the locking portion 11 includes an inner meshing surface 11a included in the same imaginary plane as the axial center of the locking nut 10, and a front end of the inner meshing surface 11a. It has an inner tapered surface 11b that is inclined with respect to the inner meshing surface 11a toward the tightening direction side of the female screw portion 12 from the bottom.

Between the locking portion 11 and the female screw portion 12, a smooth buffer portion 14 is provided. is formed.

The inner member 25 has an engaged hole 25a that supports the second engaging portion 6 of the bolt 1 with an engaging portion so that it can move back and forth in the axial direction. In the present embodiment, the engaged hole 25 a is a regular hexagonal through-hole that matches the regular hexagonal prism shape of the second engaging portion 6 . As a result, when the bolt 1 with the engaging portion is screwed by the power tool 21, the second engaging portion 6 advances through the engaged hole 25a while the locking nut 10 is fixed by the outer member 24. It is arranged so as not to prevent the screwing of the bolt 1 with the engaging portion.

-Method of tightening bolts with engaging parts-
First, in a preparation step, the fastening tool 20 described above is prepared and fixed to the power tool 21 . Necessary numbers of bolts 1 with engaging portions and locking nuts 10 are prepared. Although not shown, a washer made of fiber-reinforced resin may also be prepared if necessary.

Next, in a temporary fixing step, the bolt 1 with an engaging portion is inserted through the through holes of the first member to be fixed 31 and the second member to be fixed 32 from the side of the first member to be fixed 31, and as shown in FIG. A locking nut 10 is temporarily fixed to the tip of the bolt 1 with an engaging portion from the side of the second fixed member 32 . Temporary fixing may be performed within a range where the bolt can be easily rotated by hand, but it is desirable that the male threaded portion 4 of the bolt with engaging portion 1 and the female threaded portion 12 of the locking nut 10 engage with each other.

Next, in the bolt engaging step, the tip of the outer member 24 is inserted from the locking nut 10 side, and the engaged hole 25a at the tip of the inner member 25 is engaged with the second engaging portion 6 of the bolt 1 with an engaging portion. match.

Next, in the fastening process, the rotating shaft 21a of the power tool 21 is rotated to screw the bolt 1 with the engaging portion, and as shown in FIG. While tightening, the locking portion 11 of the nut 10 is engaged with the first engaging portion 5 of the bolt 1 with an engaging portion to prevent loosening. At this time, as shown in FIG. 7, the locking nut 10 and the tip of the bolt with engaging portion 1 are exposed from the opening 24a of the outer member 24, so it is necessary to perform the tightening operation securely while watching these. can be done.

In this fastening process, as indicated by the arrow in FIG. It is made to enter into the engaged hole 25a. As described above, when the bolt 1 with the engaging portion is screwed by the power tool 21, the engaging portion advances through the engaged hole 25a while the nut 10 is fixed by the outer member 24. It does not prevent the bolt 1 from spiraling.

In this embodiment, the locking effect is exhibited by fastening the first engaging portion 5 to the locking portion 11 of the locking nut 10 . Further, by engaging and rotating the fastening tool 20 using the tool engaging convex portion 6a from the distal end side, the male screw portion 4 can be screwed for fastening.

In the present embodiment, the rotary shaft 21a of the power tool 21 is rotated while the bolt 1 with the engaging portion and the locking nut 10, which are temporarily fixed, are fixed at the distal ends of the outer member 24 and the inner member 25, respectively. Thus, the first member to be fixed 31 and the second member to be fixed 32 are reliably fixed by causing the male threaded portion 4 of the bolt 1 with the engaging portion to thread the female threaded portion of the locking nut 10, and A locking effect between the first engaging portion 5 and the locking portion 11 can be obtained.

As described above, according to the present invention, since the second engaging portion 6 for engaging a tool is provided further ahead of the first engaging portion 5 for preventing loosening, the bolt 1 with engaging portion can be prevented from loosening. It is possible to make it possible to stop and fasten only from one side of the fastened member.

Further, according to the bolt 1 with an engaging portion according to the present embodiment, the second engaging portion 6 for engaging a tool is provided further ahead of the first engaging portion 5 for preventing loosening. , it is possible to prevent loosening and to be able to fasten only from one side of the fastened member.

The above embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its applications, or uses.

1 volt
1 bolt with engaging part
2 bolt head
3 bolt body
4 male thread
5 first engaging portion
5a Anti-loosening protrusion
5b outer meshing surface
5c outer tapered surface
6 second engaging portion
6a Tool engaging protrusion
7 steps
10 locking nut
11 locking part
11a inner meshing surface
11b inner tapered surface
12 female thread
14 buffer
15 Notch
20 fastening tool
21 power tools
21a rotating shaft
22 legs
23 flange
23a through hole
23b flat surface
23c leg attachment hole
24 outer member
24a opening
24b through hole for nut
24c chamfer
25 inner member
25a engaged hole
31 first fixed member
32 second fixed member

Claims (7)

a bolt head that can be gripped and tightened with a tool;
a rod-shaped bolt body continuous with the bolt head;
a male screw portion on the tip side of the bolt body;
a first engaging portion having locking protrusions provided at intervals in the circumferential direction at the distal end of the male screw;
A bolt with an engaging portion, characterized by comprising a second engaging portion having a projection for engaging a tool, the second engaging portion being provided further at the tip of the first engaging portion. 2. The bolt with an engaging portion according to claim 1, wherein the circumferential pitch of the locking projections is smaller than the circumferential pitch of the tool engaging projections of the second engaging portion. The maximum outer diameter of the first engaging portion is larger than the maximum outer diameter of the second engaging portion,
3. The bolt with an engaging portion according to claim 1, wherein a step is provided between the first engaging portion and the second engaging portion. 4. The bolt with an engaging portion according to any one of claims 1 to 3, wherein the bolt is an integrally molded product made of reinforcing fiber resin. 5. The method according to any one of claims 1 to 4, wherein the maximum diameter of the first engaging portion is smaller than the maximum diameter of the male screw portion and larger than the maximum diameter of the second engaging portion. A bolt with an engaging portion described. the locking convex portion of the first engaging portion forms a projection extending in the longitudinal direction of the bolt body and arranged at regular intervals in the circumferential direction;
The bolt with an engaging portion according to any one of claims 1 to 5, wherein the second engaging portion has a polygonal cross section. 7. The bolt with an engaging portion according to claim 6, wherein the locking convex portion of the first engaging portion is an external ratchet.

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