JP2019070249A - Anchor bolt and fixing method using anchor bolt - Google Patents

Abstract

To fix two members with one anchor bolt.SOLUTION: At a bolt body 110 of an anchor bolt 100, a normal screw 112 is formed on one end and a reverse screw 111 is formed on the other end. At a hexagonal prism part 110D between the normal screw 112 and the reverse screw 111, a hexagonal flange 160 is mounted in a slidable manner. At both ends of the bolt body 110, expandable first, second cylindrical parts 120, 130 are inserted. On inside wall surfaces of first, second piece members 140, 150, female screws 111, 112 screwed with the normal screw 112, the reverse screw 111 are formed respectively. End parts 144, 154 of the first, second piece members 140, 150 are inserted in gaps between the bolt body 110 and the first, second cylindrical parts 120. According to the rotation of the bolt body 110, the first, second piece members 140, 150 are attracted to each other, and the first, second cylindrical members 120, 130 expand.SELECTED DRAWING: Figure 1

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an anchor bolt, and more particularly to a spread type anchor bolt used when installing a stone or the like.

Heretofore, various methods have been taken when installing a stone monument or the like on a pedestal.
FIGS. 15 and 16 show a typical conventional example in which the monument 2 is fixed to the pedestal 3 or the like.
As shown in these figures, when installing the monument 2 on the pedestal 3, the attachment hole (insertion hole) 2B, in advance, is formed in the junction surface (lower surface) 2A on the monument 2 side and the junction surface (pedestal top surface 3A) on the pedestal 3 side. 2B, mounting holes (insertion holes) 3B, 3B are formed, and in the state where the mounting holes (insertion holes) 2B, 2B, 3B, 3B are filled with the adhesive 5, the respective insertion holes 2B, 2B, insertion holes 3B , 3B, a method is proposed in which the bonding bolt 10 is inserted and the monument 2 and the base 3 are fixed by the adhesive 5 and the bonding bolt 10.
For example, in Japanese Patent Laid-Open No. 7-34431, when fixing a stone to a fixing member, an adhesive is filled in the anchor hole of the stone, and the upper end of the anchor bolt previously attached to the fixing member is inserted into the anchor hole. Thus, there is disclosed a technique for fixing the stone and the fixing member with an adhesive.

In this method, a plurality of joint rods 6, 6, 6, 6 are arranged in advance at predetermined positions on the pedestal upper surface 3A, and the adhesive 5 is applied to the pedestal upper surface 3A (FIG. 15). The adhesive 5 is also filled in the mounting holes 3B and 3B provided on the pedestal upper surface 3A.
The adhesive 5 is also filled in the mounting holes 2B and 2B of the lower surface 2A of one of the monuments 2.

  The adhesive 5 penetrates into the gap provided between the pedestal upper surface 3A and the lower surface 2A of the monument 2 by the joint bar 6, and the lower surface 2A of the monument 2 and the pedestal upper surface 3A It will be fixed more firmly.

In FIG. 17, the method of joining the monument 2 and the base 3 is shown using the cut anchor 20 (FIG. 17 (A)) instead of the said volt | bolt 10 for joining.
In this method, the cut anchor 20 is embedded in the mounting hole 3B on the base 3 side using the dedicated driving rod 21 (FIG. 17B), and a female screw 20C formed on the inner wall surface of the cut anchor 20 is screwed. Male screw 22C of rod 22 is screwed on and attached (Fig. 17 (C)), and screwed screw rod 22 is inserted into mounting hole 2B of monument 2 filled with adhesive 5 in advance. 2 is fixed to the pedestal upper surface 3A (FIG. 17D, FIG. 18).

Further, instead of the cut anchor 20, one end of the anchor bolt 30 (FIG. 19) or the anchor bolt 40 (FIG. 20) is fixed to the mounting hole 3B on the pedestal 3 side, and the other end (bolt body of the anchor bolt 30) A method of fixing the monument 2 to the pedestal 3 by inserting the screw portion 31A of 31 and the fitting 41 attached to the head 40A of the anchor bolt 40 into the mounting holes 2B and 2B filled with the adhesive 5 beforehand. Are known.
With regard to the anchor bolt 30, in Japanese Patent Application Laid-Open No. 7-26633, in a state in which the cylindrical screw portion is inserted into the mounting hole, the cylindrical screw portion is screwed onto the nut and the nut is rotated to obtain a cylindrical shape. There is disclosed an anchor bolt in which the screw portion is pulled up, and at this time, the widening portion provided outside the cylindrical screw portion is expanded. The anchor bolt is firmly fixed to the mounting hole by the expansion portion expanding in the circumferential direction with respect to the axial center.
With regard to the spread-type anchor bolt 40, Japanese Patent Laid-Open No. 2003-90173 inserts one end of a tapered nut screwed to the bolt between the bolt and the collar, and in this state, Discloses an anchor bolt that pulls up a nut by turning to expand the collar.

  In either case using these cut anchors 20 and anchor bolts 30 and 40, although they are firmly fixed by the anchor bolt on one installation surface (the base upper surface 3A side of FIGS. 15 and 16), the other installation In the case of the surface (the lower surface 2A side of the monument 2), in any case, the adhesive 5 filled in advance in the mounting holes, the pedestal upper surface 3A, and the adhesive 5 applied to the lower surface 2A of the monument 2 There is.

JP-A-7-34431

Japanese Patent Application Laid-Open No. 7-26633

Japanese Patent Application Laid-Open No. 2003-90173

However, even when any of the conventional joint bolt 10, the cut anchor 20, and the anchor bolts 30 and 40 is used, the adhesive 5 is always used on at least one joint surface, so the following problems occur. Will occur.
That is, although the strength of the joint necessary for installation is secured by any of the above-described methods, for example, when an unexpected shaking occurs, for example, if the vertical shaking due to a large earthquake or the like is larger than expected, FIG. As shown in the example fixed with the anchor 20), there is a possibility that the monument 2 moves up and down as indicated by the solid arrow and is detached from the pedestal 3.
This is because, in the structure in which the bonding bolt or the like is fixed by the adhesive 5, if the vibration (vertical movement) in the vertical direction exceeds the unexpected, the bonding bolt or the like may be detached from the solidified adhesive 5. As long as the adhesive 5 is used, it is difficult to improve the bonding strength in the longitudinal direction.

In addition, it is known that the adhesive 5 has a reduced bonding strength due to its deterioration over time. In the state in which the adhesive strength is lowered due to the aged deterioration, if a vertical shake exceeding the assumption occurs due to a large earthquake or the like, the monument 2 may be more easily detached.
In addition, if rolling occurs frequently in a state in which the solidified adhesive 5 has deteriorated over time, a gap is generated between the bonding bolt 10 or the like and the adhesive 5 and the rolling is gradually increased by continuing the rolling. Can be When this rolling is repeated, excessive stress is applied by the shear force applied to the bonding bolt 10 or the like, and the resistance of the bonding bolt 10 or the like is reduced.

The present invention has been made in view of such circumstances, and it is a joint strength that does not have a fear that the installation object such as a monument or the like may be deviated from the installation surface even in the case of longitudinal vibration far exceeding the assumption. The task is to provide an anchor bolt that secures the
Another object of the present invention is to provide an anchor bolt capable of sufficiently maintaining the bonding strength between the installation object and the installation surface even when long years have passed.

  In order to achieve the above object, in the anchor bolt according to the first aspect of the present invention, a positive screw is formed at one end, a reverse screw is formed at the other end, and a pivoting portion is provided between the positive screw and the reverse screw. A bolt main body, an expandable first cylindrical portion into which the one end of the bolt main body is inserted, and an expandable second cylindrical portion into which the other end of the bolt main body is inserted A first piece member having a cylindrical inner wall formed with a female screw to be engaged with the positive screw of the bolt body, and a cylindrical inner wall having a female screw to be engaged with the reverse screw of the bolt body The first and second piece members are formed of a second piece member, and the first and second piece members have end portions facing each other, the bolt body, the first cylindrical portion, and the second cylindrical portion. And the first piece member and the And bridge member of is configured to be attracted to each other in the axial direction of the bolt body.

Further, according to the second invention of the present application, both of the first piece member and the second piece member are formed in a tapered shape in which the outer peripheral surface is tapered toward the center from the outer side in the axial direction of the bolt main body There is.
Further, in the third invention of the present application, the cross-sectional shape in the circumferential direction of the rotating portion is a polygon, and a hollow flange portion in which the polygon and the inner wall surface engage is slid in the axial direction of the bolt main body It is freely fitted.
Further, according to a fourth invention of the present application, at least one notch is formed in at least one of the first and second piece members so that the outer peripheral surface of the piece member is expanded in the circumferential direction as the bolt main body rotates. Is formed.
In the fifth invention of the present application, at least one of the first and second piece members whose outer peripheral surface is tapered has a cross-sectional shape in the axial direction having a thickness gradually toward the axial direction outer side of the bolt main body An increasing first taper portion and an axial cross-sectional shape are constituted by a second taper portion in which the thickness sharply increases toward the axial outer side.

The sixth invention of the present application is a method of attracting and fixing two members to each other using an anchor bolt, wherein the two members are provided with insertion holes into which one end of the anchor bolt is inserted, respectively. In the inner wall surface of at least one of the insertion holes, an enlarged recess having a diameter larger than the diameter of the insertion hole is provided, and when the first piece member and the second piece member are attracted, the expandable cylindrical portion The outer peripheral surface and the enlarged diameter recess are in contact with each other.
Further, according to the seventh invention of the present application, there is provided a bolt body having an external thread formed at one end, a cylindrical portion into which the one end of the bolt body is inserted, and an internal wall surface having an internal thread screwed with the external thread. An anchor bolt having one end formed by a tapered piece member inserted into the gap between the bolt body and the cylindrical portion, the diameter of the anchor member corresponding to the turning of the bolt body being in the piece member. At least one notch is formed so as to expand in the circumferential direction, and the piece has a first tapered portion in which the axial cross-sectional shape gradually increases in thickness toward the axial direction outer side of the bolt body; The cross-sectional shape in the direction is composed of a second tapered portion whose thickness increases sharply toward the axial outer side.

According to the first aspect of the present invention, the end portions of the first and second piece members facing each other are disposed between the bolt body and the first and second cylindrical portions. Since the first piece and the second piece can be drawn together in the axial direction of the bolt body as the bolt body is inserted into the respective gaps and the pivoting portion of the bolt body pivots. The two members can be firmly fixed by one anchor bolt.
Further, according to the second invention of the present application, the first piece member and the second piece member are both formed in a tapered shape in which the outer peripheral surface is tapered from the axially outer side to the center of the bolt body. Therefore, if the first and second piece members are drawn to each other while being inserted into the gap between the bolt body and the first and second tubular portions, the first and second tubular members expand. The degree grows smoothly.

Further, according to the third invention of the present application, the cross-sectional shape of the rotating portion in the circumferential direction is a polygon, and the hollow flange portion in which the polygon and the inner wall are engaged slides in the axial direction of the bolt main body Since a gap is provided in advance by a joint bar or the like on the joint surface of the two members to be joined because the connector is freely fitted, the flange portion is obtained even when the center of the anchor bolt is deviated from the joint surface. Can be held in the gap and turned with a tool such as a spanner.
Further, according to the fourth invention of the present application, at least one of the first and second piece members has at least one outer peripheral surface of the piece members so as to expand in the circumferential direction as the bolt body rotates. Since one cut is formed, the piece member itself for expanding the first or second cylindrical portion is also expanded with the rotation of the bolt main body, and the degree of expansion of the cylindrical portion is further increased. be able to.

Further, according to the fifth invention of the present application, at least one of the first and second piece members whose outer peripheral surface is tapered, the axial cross-sectional shape has a thickness toward the axial direction outer side of the bolt body. Since the first tapered portion which gradually increases and the second tapered portion in which the thickness in the axial cross-sectional shape rapidly increases toward the axial outer side, the degree of expansion of the piece member is made stepwise In accordance with this, the degree of expansion of the cylindrical portion can also be increased stepwise.
Further, according to the sixth invention of the present application, when the two members are drawn and fixed to each other using the anchor bolt, the two members to be fixed are provided with insertion holes into which one end of the anchor bolt is inserted. In addition, an enlarged diameter recess having a diameter larger than the diameter of the insertion hole is provided on the inner wall surface of at least one of the insertion holes, and when the first piece and the second piece are attracted, the expansion can be performed. Since the outer peripheral surface of the cylindrical portion and the enlarged diameter concave portion can be brought into contact with each other, the grip of the inner wall surface of the insertion hole by the expansion of the cylindrical portion becomes strong.

  Further, according to the seventh invention of the present application, in the anchor bolt consisting of the bolt main body, the cylindrical portion, and the tapered piece member, the diameter of the piece member is circumferential along with rotation of the bolt main body. Forming at least one cut so as to expand in the direction, and the cross section of the piece in the axial direction is a first tapered portion whose thickness gradually increases toward the axial direction outside of the bolt body; Since the shape is constituted by the second tapered portion in which the thickness sharply increases outward in the axial direction, the degree of expansion of the cylindrical portion can be further increased according to the rotation of the bolt main body.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a perspective view showing an anchor bolt 100 according to the present invention.
As shown in FIG. 1, the anchor bolt 100 includes a bolt body 110, first and second cylindrical portions (cylindrical portions) 120 and 130, and a tapered first outer peripheral surface tapered inward. , Second piece members 140 and 150, and a hexagonal flange 160 (hexagonal flange).

  The anchor bolt 100 configured in this way has mounting holes (insertion holes) provided on both sides (the first cylindrical portion 120 and the second cylindrical portion 130) at the installation target (monument), and the mounting surface The first frame member 140 and the second frame member 150 are attracted to each other by rotating the bolt main body 110 inserted into the mounting holes (insertion holes) provided in the base) and in the inserted state. The outer end portions 120A and 130A of the first cylindrical portion 120 and the second cylindrical portion 130 are expanded by the piece members 140 and 150 in the circumferential direction.

Therefore, the outer wall 120A, 130A of the first and second cylindrical portions 120, 130 is the inner wall surface of the mounting hole formed in the installation target (monument) or the mounting hole formed in the installation surface (the pedestal upper surface) Will grip you.
When the bolt body 110 is further rotated while the outer end portions 120A and 130A grip the inner wall surface of the mounting hole, the gripping force is enhanced, and the first piece 140 and the second piece 150 are further drawn. It becomes fit, and while strengthening grip power, it attracts while the installation object (monument) and the installation surface (the pedestal upper surface) are fixed.

FIG. 2 is an exploded perspective view for explaining the details of each part of anchor bolt 100. As shown in FIG.
As shown in this figure, the bolt body 110 of the anchor bolt 100 is provided with a first screw portion 110A having a reverse screw (male thread) 111 formed thereon and a second screw portion having a positive screw (male thread) 112 formed thereon. A threaded portion 110B is provided, and a section (a hexagonal column) 110D having a hexagonal (polygonal) cross section is formed between them (a portion where no thread is formed). The hexagonal column portion 110D is a pivoting portion of the bolt body 110.
Further, a tip end of the bolt main body 110 on the side of the first screw portion 110A is a tapered cylindrical portion 110C for expanding the first piece member 140.

The hexagonal flange 160 is inserted so as to be able to move freely in the hexagonal column portion 110D at the center of the bolt body 110, and is slidable in the axial direction of the bolt body 110.
When the hexagonal flange 160 is rotated, the hexagonal column portion 110D is also rotated in the circumferential direction (rotation of the bolt main body 110).
Positioning projections 121, 121, 131, 131 are provided at the end (inner end) 120B, 130B from the center of the first and second cylindrical portions 120, 130, respectively.
The positioning projections 121, 121, 131, 131 are formed in the first and second cylindrical portions 120, 130 by bending.

Among them, as described later (see FIG. 11), the positioning projections 131 and 131 are used to place one end of the anchor bolt 100 on the pedestal upper surface (installation surface) 3A, and positioning grooves 3C and 3C on the pedestal upper surface 3A side. The anchor bolt 100 and the mounting holes 3B and 3B are aligned. On the other hand, the positioning projections 121, 121 are fitted in alignment grooves 2C, 2C provided on the lower surface 2A of the monument 2, and alignment between the anchor bolt 100 and the mounting holes 2B, 2B is performed.
In the positioning projections 121, 121, 131, 131, even when the bolt body 110 is rotated when the anchor bolt 100 is tightened, the first and second cylindrical portions 120, 130 are in contact with the monument 2 or the pedestal 3. It also functions as a stopper to prevent relative rotation.

Further, guide grooves 122, 122, 132, 132 are also formed in the first and second cylindrical portions 120, 130, respectively.
The projections 142, 142, 152, 152 on the side of the first and second piece members 140, 150 are engaged with the guide grooves 122, 122, 132, 132, respectively.
As a result, even when the bolt body 110 is pivoted and the first and second piece members 140 and 150 are attracted to each other, the first and second cylindrical portions 120 and 130 and the first and second piece members 140 are produced. , 150 do not rotate relative to each other.
As a result, even when the bolt body 110 is rotated, the first piece member 140 and the second piece member 150 attract each other in the first and second cylindrical portions 120 and 130. .

Spreading slits 123, 123, 133, 133 are formed in the first and second cylindrical portions 120, 130, respectively.
By providing the expanding slits 123, 123, 133, 133, as described in detail later, when the first piece 140 and the second piece 150 are axially attracted to each other, the first, The outer end portions 120A, 130A of the second cylindrical portions 120, 130 are expanded in the circumferential direction.
Furthermore, expanding slits 143, 143, 143, 143 are formed in the first piece member 140, and the inner wall surface of the first piece member 140 is a taper of the bolt main body 110, as described in detail later. It is spread by the insertion of the cylindrical portion 110C (see FIGS. 4 and 5 described later).

Although the size of the anchor bolt 100 is not particularly limited, in this embodiment, the axial length 102 mm of the bolt body 110, the first and second screw portions 110A and 110B both have a length of 33 mm, and a hexagon The length of the column 110D is 36 mm, and the opposite side is 8 mm.
The first and second cylindrical portions 120 and 130 have a length of 32 mm, an outer diameter of 13.5 mm, an inner diameter of 10.5 mm, a width of 2 mm for the positioning projections 121, 121, 131, 131, and the projections 121, 121, 131 131 protrudes from the outer peripheral surface, the length is 5 mm, the width of the guide grooves 122, 122, 132, 132 is 2.2 mm, the length is 23 mm, the width of the expansion slits 123, 123, 133, 133 is 1 mm, the length is 23 mm It has become.

The first and second piece members 140, 150 have an outer diameter of 13.5 mm on the outer side, an outer diameter of 10 mm on the center side, and a length of 1.5 mm protruding from the outer peripheral surface of the protrusions 142, 142, 152, 152. , Thickness is 1 mm.
In addition, the hexagonal flange 160 has an inner diameter of 8 mm, an outer diameter of 17 mm, and a thickness of 5 mm.

Next, with reference to FIG. 3, an operation (operation of attracting) of the first and second piece members 140 and 150 accompanied by the rotation of the bolt main body 110 will be described.
As described above, the first and second piece members 140 and 150 do not rotate in the circumferential direction with respect to the first and second cylindrical portions 120 and 130.
Further, the first and second cylindrical portions 120 and 130 do not rotate with respect to the installation object (the monument 2) and the installation surface (the pedestal upper surface 3A) by the action of the positioning protrusions 121, 121, 131 and 131 . As a result, the first and second piece members 140 and 150 also do not rotate with respect to the installation target (the monument 2) and the installation surface (the pedestal upper surface 3A).

In this state, when the bolt body 110 is rotated in the arrow direction in FIG. 3A, the first piece 140 and the second piece 150 are in the direction indicated by the white arrow in FIG. 3A. Move to (attract).
When the first piece 140 and the second piece 150 attract each other (FIG. 3B), the first and second cylindrical portions 120 and 130 expand (not shown).
As the attraction progresses and the axial movement of one of the piece members (in the illustrated example, the second piece member 150) becomes impossible (the second cylindrical portion 130 grips the inner wall of the mounting hole), a further bolt body By the rotation of 110, the bolt body 110 starts to move rightward in FIG. 3C (black arrow).
At this time, as long as the first piece member 140 is movable, the first piece member 140 is drawn toward the second piece member 150 by the rotation of the bolt body 110 (FIG. 3 (C White arrow)).

Next, the configuration and operation of the spread type first frame member 140 according to the present invention will be described with reference to FIGS. 4 and 5.
As described above, the spreading slits 143, 143, 143, 143 are formed in the first piece member 140 (FIG. 1, FIG. 2).
The first piece 140 is functionally divided into a first area 140A and a second 140B, as shown in FIG.
Among them, the inside of the first region 140A is cylindrical with a constant diameter, but the inside of the second region 140B is tapered such that the diameter becomes smaller toward the axial direction outer side of the bolt main body 110 (Fig. 4 (A)).
The first piece member 140 has a tapered shape in which the outer peripheral surface spreads outward, and a tapered shape in which the inner wall narrows outward, so that the degree to which the thickness of the second region 140B increases is the first region The thickness of 140A becomes larger than the degree of increase.

  Since the degree of increase of the thickness of the first piece member 140 is two steps which are different in the first region 140A and the second region 140B, the first piece member 140 is formed as shown in FIG. 4 (B). When the wall surface 140a of the area 140A of 1 and the wall surface 140b of the second 140B are flush with each other, the degree to which the thickness of the first piece member 140 increases is steeper on the outside from the substantially central portion thereof.

FIG. 5 is a cross-sectional view showing a state in which the bolt main body 110 is actually screwed to the first piece member 140 of the above configuration.
Before tightening of the anchor bolt 100, the male screw 111 of the bolt main body 110 and the female screw 141 of the first piece member 140 are kept in a screwed state about two to three turns (FIG. 5 (A) ).
When the anchor bolt 100 is inserted into the mounting hole (not shown) and the bolt body 110 is rotated, the male screw 111 of the bolt body 110 is further screwed with the female screw 141 of the first piece member 140. The threaded portion 110A of 1 moves to the end on the left side in the drawing of the first area 140A of the first piece member 140 (FIG. 5 (B)).
When the bolt body 110 is further rotated from this state, the tapered cylindrical portion 110C of the bolt body 110 spreads the tapered surface of the second 140B in the circumferential direction, and the inner wall 140a of the first region 140A and the second The inner wall 140b of the frame 140B becomes flush, and the outer periphery of the first piece member 140 spreads extremely at the approximate center (FIG. 5 (C)).

Next, the expansion operation of the anchor bolt 100 accompanying the rotation of the bolt main body 110 will be described using FIGS.
As described above, the first and second piece members 140 and 150 and the first and second cylindrical portions 120 and 130 do not rotate relative to each other, and the first and second cylindrical portions 120 and 130 do not rotate. 130 do not rotate with respect to the installation target (2) and the installation surface (base 3).
The anchor bolt 100 is inserted into the first and second cylindrical portions 120 and 130 at both ends of the bolt body 110 before tightening (FIG. 6), and in this state, the male screw 111 of the bolt body 110 and the first The female screw 141 of the bridge member 140 is lightly screwed on the female screw 112 and the female screw 151 of the second bridge member 150, so that a state in which tightening can be performed is maintained (FIG. 7).

When the bolt body 110 is turned from this state (rotation in the arrow direction in FIG. 7), the male screw (reverse screw) 111 on the bolt body 110 side and the female screw 141 of the first piece member 140 are screwed together at one end. Since the male screw (positive screw) 112 on the bolt body 110 side and the female screw 151 of the second piece member 150 are screwed together at the other end side, the first and second piece members 140, 150 are It moves in the axial direction so as to attract each other (from the state of FIG. 7 to the state of FIG. 8).
When the first and second piece members 140 and 150 attract each other, the end portions 144 and 154 of the piece members enter the gap between the bolt body 110 and the first and second cylindrical portions 120 and 130, and the first and first pieces The two cylindrical portions 120 and 130 both start to open.

When the bolt body 110 is further rotated in the direction of the arrow in the drawing from the state shown in FIG. 8, the first and second piece members 140 and 150 are further drawn, and the ends 144 and 154 thereof The gap between the first cylindrical portion 120 and the gap between the bolt body 110 and the second cylindrical portion 130 are further pushed apart (FIG. 9).
Then, when at least one of the cylindrical portions (the second cylindrical portion 130 in FIG. 9) grips the inner wall surface of the mounting hole (not shown) and becomes locked, the axial direction of the piece member (the second piece member 150) Movement is restricted (they can not move freely).

When the bolt body 110 is further rotated from the state shown in FIG. 9, the movement of one of the piece members (the second piece member 150) is prohibited (in fact, it bites into the gap by further tightening) Then, the bolt body 110 starts moving rightward in FIG. 9 inside the anchor bolt 100 (from the state of FIG. 9 to the state of FIG. 10).
At this time, the first piece member 140 moves to the right in the axial direction with respect to the bolt body 110 by screwing of the female screw 141 and the male screw 111, but the bolt body 110 itself also moves to the right in the axial direction. The degree of movement of the piece member 140 of 1 in the axial direction (right direction in the drawing) inside the anchor bolt 100 is increased.
As a result, the degree of penetration of the end 144 of the first piece 140 into the gap is increased, and the degree of expansion of the first cylindrical portion 120 is also increased.

Furthermore, as described above, the first piece member 140 is provided with the spreading slits 143, 143, 143, 143, and the taper in which the inner wall 140a of the first region 140A is tapered toward the outside. Since the first piece member 140 itself is expanded in the circumferential direction by the shape (see FIGS. 4 and 5), the degree of the expansion of the first cylindrical portion 120 is further increased.
Thus, by setting the degree of expansion on the side of the first cylindrical portion 120 to be larger than the degree of expansion on the side of the second cylindrical portion 130, one end portion of the anchor bolt 100 (the first cylindrical portion 120 Side) is inserted into the large diameter mounting hole (insertion hole), and the other end (the second cylindrical portion 130 side) is inserted into the small diameter mounting hole (insertion hole). It can be secured.

Next, using the anchor bolt 100 according to the present invention, the monument (installation target) 2 is actually fixed to the pedestal upper surface (installation surface) 3A, and the pedestal (installation target) 3 is further concrete top surface (concrete installation surface) 4A The method of fixing to is described with reference to FIG. 11 and FIG.
In fixing the monument 2 to the pedestal upper surface 3A, first, the joint rod 6 (thickness 6 mm, larger than the thickness 5 mm of the hexagonal flange 160) is disposed at a predetermined position of the pedestal upper surface 3A (4 in the illustrated example) Location).
Next, the anchor bolt 100 is inserted into the mounting holes 3B and 3B provided in advance on the pedestal upper surface 3A. In this example, the second cylindrical portion 130 side of the anchor bolt 100 is inserted (FIG. 12 (A)). At this time, the positioning projections 131, 131 and the positioning grooves 3C, 3C are fitted.
In this state, the monument 2 is lowered while aligning the pedestal 3 and the monument 2 (FIG. 11, FIG. 12 (B)), and the first cylindrical portion 120 side of the anchor bolt 100 is attached to the mounting hole of the monument 2 (Insertion hole) 2B, insert into 2B. At this time, the positioning projections 121, 121 are fitted in the alignment grooves 2C, 2C.

When lowering of the monument 2 to the pedestal upper surface 3A is completed, a gap for tightening operation is formed between the pedestal upper surface 3A and the lower surface 2A of the monument 2 by the joint rods 6, 6, 6, 6 arranged on the pedestal upper surface 3A. (About 6 mm) is secured (FIG. 12 (C)).
By thus providing a clearance for tightening work, the hexagonal flange 160 (5 mm in thickness) of the anchor bolt 100 comes to be positioned in the clearance, and is rotated by a tool such as a spanner. be able to.
In addition, since the hexagonal flange 160 is slidable in the axial direction of the bolt body 110, even if the center of the anchor bolt 100 is out of the gap secured by the joint rod 6, the hexagonal flange 160 is always It can be positioned inside, allowing pivoting of the bolt body 110.

When the hexagonal flange 160 is rotated clockwise in FIG. 11 using a tool (not shown) such as a spanner, the male screw (positive screw) 112 of the bolt body 110 and the female screw 151 of the second piece member 150 The second piece member 150 is pulled upward in the figure by screwing.
On the other hand, since the male screw (reverse screw) 111 of the bolt main body 110 is screwed with the female screw 141 of the first piece member 140, the first piece member 140 is pulled down in the figure.
As a result, the first piece member 140 and the second piece member 150 attract each other in the vertical direction in FIGS. 11 and 12.
When the first piece 140 and the second piece 150 attract each other, the ends 144 and 154 of the first piece 140 and the second 150 form the bolt body 110 and the first and second cylinders. It enters the gap between the portions 120 and 130, and pushes the outer end portions 120A and 130A of the first and second cylindrical portions 120 and 130 in the circumferential direction (FIG. 12D).

When the hexagonal flange 160 is further turned clockwise, the expansion of the second cylindrical portion 130 inserted to the mounting holes 3B and 3B side is maximized, and the outer end 130A of the second cylindrical portion 130 is the mounting hole 3B. , And grip the inner wall surface of 3B (Fig. 12 (E)).
Here, in the center of the inner wall of the mounting holes 3B, 3B, an enlarged diameter recess 3F is provided to enhance the gripping effect of the second cylindrical portion 130, whereby the outer end 130A of the second cylindrical portion 130 is provided. Is fitted into the enlarged diameter recess 3F to increase its coupling force.
At this time, movement of the second piece member 150 inside the anchor bolt 100 is restricted (substantially prohibited).

When the movement of the second piece member 150 (the upward movement in FIG. 12) is restricted, when the hexagonal flange 160 is further rotated, the elevation of the second piece member 150 remains stopped. The bolt body 110 moves downward in the anchor bolt 100 by screwing the female screw 151 of the second piece member 150 and the male screw 112 of the bolt body 110.
Further, since the female screw 141 of the first piece member 140 is screwed with the male screw 111 of the pivoting bolt main body 110 (FIG. 9), the first piece member 140 descends in the anchor bolt 100. Keep doing.
Thus, since the bolt body 110 itself is lowered and the first piece member 140 is further lowered with respect to the bolt body 110, the first piece member 140 is a gap between the bolt body 110 and the first cylindrical portion 120. The degree of penetration of the first cylindrical portion 120 is increased.

As a result, even if the opening diameter of the mounting hole 2B into which the first cylindrical portion 120 is inserted is larger than the other mounting hole 3B, one anchor bolt 100 can be used to install the installation target (monument 2) and the installation surface (pedestal top) 3A) can be firmly fixed.
Here, an enlarged diameter recess 2F for enhancing the gripping effect of the outer end 120A of the first cylindrical portion 120 is also provided in the central portion of the inner wall of the mounting holes (insertion holes) 2B and 2B, thereby the outer end 120A. Is fitted to the enlarged diameter recess 2F to increase its coupling force.
In particular, in the anchor bolt 100, the first piece member 140 itself is also expanded by the rotation of the bolt body 110, and further, in the first region 140A of the first piece member 140. In contrast, since the taper of the cross-sectional shape of the second 140B is made steep, the first part of the expanding type is started from the time when the first screw portion 110 abuts on the tapered inner wall 140b of the second 140B. As the degree of expansion of the member 140 increases (FIGS. 5B to 5C), the degree of expansion of the first cylindrical portion 120 also increases.

  As described above, since the anchor bolt 100 according to the present invention has different degrees of circumferential expansion (spreading) of the first cylindrical portion 120 and the second cylindrical portion 130 (in the case of the first cylindrical portion 120 Suddenly, as in this embodiment, when the mounting holes (insertion holes) 2B and 2B of the monument 2 and the mounting holes (insertion holes) 3B and 3B of the pedestal 3 have different diameters, Even if the cylindrical part is expanded and gripped in the mounting hole, the other cylindrical part continues to be expanded, so that mounting holes with different diameters are formed between the installation object and the installation surface However, strong connection by the anchor bolt 100 becomes possible.

The anchor bolt 100 is also used when fixing the pedestal 3 to the concrete installation surface 4A (FIG. 11).
In this case, four mounting holes 3E, 3E, 3E, 3E are provided in the lower installation surface 3D of the pedestal 3, and mounting holes 4E, 4E, 4E, 4E are also provided in the concrete installation surface 4A.
Further, joint rods 6, 6, 6, 6 are provided between the installation surface 3D and the concrete installation surface 4A, and a clearance (work clearance 6 mm) is secured between the installation surface 3D and the concrete installation surface 4A. Be done.
Even when the pedestal 3 is installed on the concrete installation surface 4A, the pedestals are aligned while the one end (the first cylindrical portion 120 side) of the anchor bolt 100 is inserted into the mounting holes 4E, 4E, 4E, 4E. 3 may be lowered from above (FIG. 11).
Thereafter, the hexagonal flange 160 can be rotated clockwise and the pedestal 3 can be firmly installed on the concrete installation surface 4A by the anchor bolt 100 in the same procedure as in the case of installing the monument 2.

As described above, in this embodiment, when installing the monument 2 on the pedestal 3, both can be firmly fixed by the anchor bolt 100. Even if a force is applied, the anchor bolt 100 firmly grips the wall surface of the mounting hole 2B of the monument 20 and locks it, so even if an unexpected large vertical vibration occurs, the anchor bolt 100 does not There is no risk of coming off in the vertical direction with respect to the pedestal 3.
Also, since no adhesive is used, it is not necessary to consider aging.
In addition, since the monument 20 is firmly fixed not only in the vertical direction but also in the horizontal direction, "shifting" does not occur even if slight movement (vibration) in the horizontal direction occurs continuously, and the anchor bolt The resistance to 100 shear forces is also improved.

In the anchor bolt 100 of this embodiment, only the first piece member 140 can be expanded. However, as shown in FIG. 153 and 153 may be formed to be able to be expanded.
Further, in this embodiment, the hexagonal flange 160 is inserted into the hexagonal column portion 110D of the bolt main body 110, and the bolt main body 110 is pivoted by pivoting the hexagonal flange 160. As shown in 14, without providing a hexagonal flange, the hexagonal column portion 110D may be directly rotated by the spanner 8.

Moreover, in the above-mentioned embodiment, although the bolt main body 110 was made into the cylinder, as long as an external thread can be formed, another cross-sectional shape (for example, polygon) may be sufficient.
Further, in the embodiment described above, the drive portion (hexagonal column portion 110D) of the bolt main body 110 and the flange (hexagonal flange 160) attached thereto are made hexagonal, but the bolt main body 110 can be rotated. If it is, it may be another shape (other polygon).

In the embodiment described above, an example is shown in which the first screw portion 110A has a reverse screw and the second screw portion has a positive screw, but the first screw portion 110A has a positive screw, a second screw Of course, a reverse screw may be formed on the screw portion. In this case, as a matter of course, the positive and reverse of the female screw 141 of the first piece member 140 and the female screw 151 of the second piece member 150 are reversed.
In the embodiment described above, the cylindrical portion to be expanded is a cylinder, but if it can be expanded to grip the mounting hole (insertion hole) to be installed, a hollow polygonal column or the like may be used. It may be configured.

It can be used not only for fixing stone materials such as monuments, but also for joining concrete with stone materials and concrete.
Furthermore, it is a matter of course that the anchor bolt of the present invention can be used for bonding of any other material, for example, wood or plastic, provided that mounting holes (insertion holes) can be formed in the two joint surfaces.

It is a perspective view showing the whole composition of anchor bolt 100 concerning the present invention. FIG. 7 is an exploded perspective view of the anchor bolt 100. It is explanatory drawing which shows the axial direction movement of the bolt main body 110 of the anchor bolt 100, and the piece members 140 and 150. As shown in FIG. FIG. 14 is a cross-sectional view showing an inner shape of a piece member 140. It is sectional drawing which shows the effect | action of the piece member 140 when the volt | bolt main body 110 rotates. It is a perspective view which shows how to assemble the anchor bolt 100. As shown in FIG. It is a perspective view and a sectional view showing the state of anchor bolt 100 before fastening. It is a perspective view and a sectional view showing the state of anchor bolt 100 in the middle of tightening. It is a perspective view and sectional drawing which show the state of the anchor bolt 100 when the expansion | deployment operation | movement of the 2nd cylindrical part 130 by the piece member 150 is complete | finished. It is a perspective view and a sectional view showing a state of anchor bolt 100 at the time of expansion operation of the 1st cylindrical part 120 by piece member 140 also ending. It is a perspective view showing an example which fixes monument 2 and pedestal 3, pedestal 3 and concrete installation side 4A using anchor bolt 100 concerning the present invention. FIG. 10 is a cross-sectional view for explaining the action of the anchor bolt 100 when fixing the monument 2 to the pedestal 3; It is a perspective view which shows the anchor bolt which provided the slit for expansion and was made to expand also to a 2nd piece member. It is a perspective view which shows the method of rotating an anchor bolt with the spanner 8 without providing the hexagonal flange 160. FIG. It is a perspective view which shows the method of fixing the monument 2 to the base 3 using the adhesive agent 5 and the volt | bolt 10 for joining conventionally performed. It is sectional drawing which shows a mode that the monument 2 is fixed to the base 3 by the adhesive agent 5 and the volt | bolt 10 for joining. It is a figure which shows a mode that the monument 2 is fixed to the base 3 using the conventional cut anchor 20. FIG. It is sectional drawing which shows a mode that the monument 2 is fixed to the base 3 using the conventional cut anchor 20. As shown in FIG. FIG. 6 is a view showing an anchor bolt 30 that can be used when fixing the monument 2 to the pedestal 3; FIG. 6 is a view showing an anchor bolt 40 that can be used when fixing the monument 2 to the pedestal 3; It is sectional drawing which shows a mode that the monument 2 fixed to the base 3 remove | deviates from the base 3 by pitching.

2 monuments (target for installation)
2A lower surface 3 pedestal 3A pedestal upper surface (installation surface)
4A concrete installation surface 5 adhesive 6 joint rod 100 anchor bolt 110 bolt main body 110A first threaded portion 110B second threaded portion 111, 112 male thread 120 first cylindrical portion (first cylindrical portion)
120A, 130A outer end 130 second cylindrical portion (second cylindrical portion)
140 first piece member 141 female screw 144 end 150 second piece member 151 female screw 154 end 160 hexagonal flange (flange part)

The present invention has been made in view of such circumstances, and it is a joint strength that does not have a fear that the installation object such as a monument or the like may be deviated from the installation surface even in the case of longitudinal vibration far exceeding the assumption. The task is to provide an anchor bolt that secures the
Another object of the present invention is to provide an anchor bolt capable of sufficiently maintaining the bonding strength between the installation object and the installation surface even when long years have passed.
Also, when the diameter of the mounting hole for installation such as a monument is larger than the diameter of the mounting hole formed on the mounting surface, mounting holes with different diameters are formed for the mounting surface and the mounting object It is an object of the present invention to provide an anchor bolt capable of firmly fixing an installation object to an installation surface even in the case.

In order to achieve the above object, in the anchor bolt of the first invention of the present application, a positive screw or a reverse screw is formed at one end, a reverse screw or a positive screw is formed at the other end, and between the positive screw and the reverse screw A bolt body provided with a pivoting portion, an expandable first cylindrical portion into which the one end of the bolt body is inserted, and an expandable portion into which the other end of the bolt body is inserted A second tubular portion, a first piece member having a cylindrical inner wall formed with a female screw which is screwed with a positive screw or a reverse screw of the bolt main body, and a cylindrical inner wall having the bolt main body The second and third members are provided with a female screw in which a reverse screw or a positive screw is screwed, and the first and second pieces have end portions facing each other, the bolt main body and the first bolt Inserted into respective gaps generated between the first cylinder portion and the second cylinder portion, and the pivot portion of the bolt main body With the rotation, in the first frame member and the second frame member and an anchor bolt which is attractable configured to each other in the axial direction of the bolt body, the rotating unit includes a circumferential cross-section Is formed into a polygonal shape, and a hollow flange portion in which the polygonal surface and the inner wall surface engage is slidably fitted in the axial direction of the bolt main body, and the first piece member Is configured such that the degree of expansion of the first tubular portion is larger than the degree of expansion of the second tubular portion by the second piece member .

In the second invention of the present application, the first piece member is formed in a tapered shape in which the outer peripheral surface is tapered from the outside in the axial direction of the bolt main body toward the center, and the axial direction of the first piece A first tapered portion is formed whose thickness increases in the axial direction outward of the bolt main body in the cross-sectional shape, and the axial cross-sectional shape increases in thickness sharply in the axial direction outside the first tapered portion. A tapered portion of 2 is formed .
In the third invention of the present application , at least one notch is formed in the first piece member, and the notch is opened as the bolt body rotates, so that the outer peripheral surface of the piece member is circumferentially It is spreading.

Also, a fourth aspect of the present invention is the normal threaded at one end, hand thread is formed at the other end, the bolt body rotating unit is provided between the positive screw and the hand thread, the bolt An expandable first cylindrical portion into which the one end of the main body is inserted, an expandable second cylindrical portion into which the other end of the bolt body is inserted, and a cylindrical inner wall surface A first piece member formed with a female screw to be engaged with the positive screw of the bolt body, and a second piece formed to a cylindrical inner wall surface with a female screw to be engaged with the reverse screw of the bolt body Consisting of members, the first and second piece members have their respective opposite ends formed between the bolt body and the first and second cylindrical portions. And the first piece member and the second piece member are axially inserted in the axial direction of the bolt body as the turning portion of the bolt body is turned. In the anchor bolt which is configured to be mutually attractable, the pivoting portion has a hollow in cross-sectional shape in the circumferential direction and is formed into a polygon, and the polygon and the inner wall surface engage with the pivoting portion. The flange portion is slidably fitted in the axial direction of the bolt body, and the outer peripheral surface of both the first piece member and the second piece member is directed from the axially outer side of the bolt body toward the center A tapered shape is formed, and at least one of the first and second piece members has an axial cross-sectional shape toward the center side, and a thickness gradually decreases toward the axial outer side of the bolt main body A first tapered portion is formed, and a second tapered portion is formed on the axially outer side, with an axial cross-sectional shape having a thickness sharply increasing toward the axially outer side.
Further, according to the fifth invention of the present application, at least one notch extending in the axial direction is formed in at least one of the first piece member or the second piece member, and the notch is formed along with the rotation of the bolt main body By opening, the outer peripheral surface of the piece member is configured to spread in the circumferential direction.
The sixth invention of the present application is a method of attracting and fixing two members to each other using an anchor bolt, wherein the two members are provided with insertion holes into which one end of the anchor bolt is inserted, respectively. In the inner wall surface of at least one of the insertion holes, an enlarged recess having a diameter larger than the diameter of the insertion hole is provided, and when the first piece member and the second piece member are attracted, the expandable cylindrical portion the outer peripheral surface and said radially enlarged recess you are into contact.

According to the first aspect of the present invention, the end portions of the first and second piece members facing each other are disposed between the bolt body and the first and second cylindrical portions. Since the first piece and the second piece can be drawn together in the axial direction of the bolt body as the bolt body is inserted into the respective gaps and the pivoting portion of the bolt body pivots. The two members can be firmly fixed by one anchor bolt.
Further, even in the case where the diameter of one of the two mounting holes of the two members is larger than the diameter of the mounting hole formed in the other member, one anchor bolt secures these two members. It can be fixed to
Further, according to the second invention of the present application, since the first piece member is formed in a tapered shape in which the outer peripheral surface is tapered from the outside in the axial direction of the bolt main body toward the center, the first piece member However, if they are mutually drawn while being inserted into the gap between the bolt body and the first cylindrical portion, the degree of expansion of the first cylindrical portion smoothly increases.

According to the third aspect of the present invention, the the first frame member, the outer peripheral surface of this該駒member, so as to spread in the circumferential direction with the rotation of the bolt body to form at least one notch Therefore, the piece member itself for expanding the twelfth cylindrical portion is also expanded with the rotation of the bolt main body, and the degree of the expansion of the cylindrical portion can be further increased.
Further, according to the fourth invention, the end portions of the first and second piece members facing each other are between the bolt body and the first and second cylindrical portions. Since the first piece and the second piece can be drawn together in the axial direction of the bolt body as the bolt body is inserted into the respective gaps and the pivoting portion of the bolt body pivots. The two members can be firmly fixed by one anchor bolt.
Further, even in the case where the diameter of one of the two mounting holes of the two members is larger than the diameter of the mounting hole formed in the other member, one anchor bolt secures these two members. It can be fixed to ,

Further, according to the fifth invention of the present application, at least one of the first and second piece members has at least one outer peripheral surface of the piece members so as to expand in the circumferential direction as the bolt body rotates. Since one cut is formed, the piece member itself for expanding the first or second cylindrical portion is also expanded with the rotation of the bolt main body, and the degree of expansion of the cylindrical portion is further increased. be able to.

Further, according to the sixth invention of the present application, when the two members are drawn and fixed to each other using the anchor bolt, the two members to be fixed are provided with insertion holes into which one end of the anchor bolt is inserted. In addition, an enlarged diameter recess having a diameter larger than the diameter of the insertion hole is provided on the inner wall surface of at least one of the insertion holes, and when the first piece and the second piece are attracted, the expansion can be performed. Since the outer peripheral surface of the cylindrical portion and the enlarged diameter concave portion can be brought into contact with each other, the grip of the inner wall surface of the insertion hole by the expansion of the cylindrical portion becomes strong.

In the second invention of the present application, the first piece member is formed in a tapered shape in which the outer peripheral surface is tapered from the outside in the axial direction of the bolt main body toward the center, and the axial direction of the first piece A first tapered portion is formed whose thickness increases in the axial direction outward of the bolt main body in the cross-sectional shape, and the axial cross-sectional shape increases in thickness sharply in the axial direction outside the first tapered portion. 2 of the tapered portion that are formed.

In the third invention of the present application , at least one notch is formed in the first piece member, and the notch is opened as the bolt body rotates, so that the outer peripheral surface of the piece member is circumferentially It is spreading.

According to the first aspect of the present invention, the end portions of the first and second piece members facing each other are disposed between the bolt body and the first and second cylindrical portions. Since the first piece and the second piece can be drawn together in the axial direction of the bolt body as the bolt body is inserted into the respective gaps and the pivoting portion of the bolt body pivots. , Ru can firmly fix the two members with one of the anchor bolt.

Further, even in the case where the diameter of one of the two mounting holes of the two members is larger than the diameter of the mounting hole formed in the other member, one anchor bolt secures these two members. It can be fixed to

Further , according to the second invention of the present application, since the first piece member is formed in a tapered shape in which the outer peripheral surface is tapered from the outside in the axial direction of the bolt main body toward the center, the first piece member However, if they are mutually drawn while being inserted into the gap between the bolt body and the first cylindrical portion, the degree of expansion of the first cylindrical portion smoothly increases.

Further , according to the third invention of the present application , at least one notch is formed in the first piece member such that the outer peripheral surface of the piece member is expanded in the circumferential direction as the bolt main body rotates. The piece member itself for expanding the twelfth cylindrical portion is also expanded with the rotation of the bolt main body, and the degree of expansion of the cylindrical portion can be further increased.

Claims (7)

A bolt body having a positive screw formed at one end and a reverse screw at the other end, and a pivoting portion provided between the positive screw and the reverse screw;
An expandable first cylindrical portion into which the one end of the bolt body is inserted;
An expandable second cylindrical portion into which the other end of the bolt body is inserted;
A first piece member having a cylindrical inner wall surface and a female screw formed on the positive screw of the bolt main body;
It consists of the 2nd piece member in which the female screw which screwed with the reverse screw of the above-mentioned bolt main part was formed in the cylindrical inner wall surface,
The ends of the first and second piece members facing each other are inserted into respective gaps generated between the bolt body and the first cylindrical portion and the second cylindrical portion.
The anchor characterized in that the first piece member and the second piece member can be drawn together in the axial direction of the bolt body in accordance with the rotation of the turning portion of the bolt body. bolt. The first piece member and the second piece member are both formed in a tapered shape in which the outer peripheral surface is tapered from the axially outer side to the center of the bolt main body. Anchor bolt as described in. The sectional shape in the circumferential direction of the rotating portion is a polygon, and a hollow flange portion engaged with the polygon and the inner wall surface is slidably fitted in the axial direction of the bolt body. The anchor bolt according to claim 1 or 2. At least one notch is formed in at least one of the first and second piece members so that the outer peripheral surface of the piece member is expanded in the circumferential direction as the bolt body rotates. The anchor bolt according to any one of claims 1 to 3. At least one of the first and second piece members whose outer peripheral surface is tapered is
A first tapered portion in which the axial sectional shape gradually increases in thickness toward the axial outer side of the bolt body, and a second tapered portion in which the axial sectional shape rapidly increases in thickness toward the axial outer side The anchor bolt according to any one of claims 2 to 4, characterized in that it comprises: A method of attracting and fixing two members to each other using the anchor bolt according to any one of claims 1 to 5,
Each of the two members is provided with an insertion hole into which one end of the anchor bolt is inserted,
Providing an enlarged recess on the inner wall surface of at least one of the insertion holes with a diameter larger than the diameter of the insertion hole;
Fixing using an anchor bolt characterized in that when the first piece member and the second piece member are attracted, the outer peripheral surface of the expandable cylindrical portion abuts on the enlarged diameter recess portion Method. A bolt body with an external thread formed at one end,
A cylindrical portion into which the one end of the bolt body is inserted;
It is an anchor bolt which comprises a female screw screwing with the male screw and is formed on an inner wall surface, and a tapered piece member having one end inserted into a gap between the bolt body and the cylindrical portion,
At least one notch is formed in the piece member such that the diameter thereof expands in the circumferential direction as the bolt body rotates.
In the piece member, the first tapered portion in which the axial sectional shape gradually increases in thickness toward the axial outer side of the bolt main body, and the axial sectional shape rapidly in the axial outward direction. An anchor bolt characterized by comprising an increasing second taper portion.