JP2003268884A - Anchor bolt and anchor bolt fixing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anchor bolt which is rigidity fixed to an object without a fear of disengagement thereof even if a strong tensile force is applied thereto, and to provide an anchor bolt fixing method. <P>SOLUTION: The anchor bolt is formed of a bolt shaft body 1, an engaging member 2, a nut 3, and a thrusting member 4. The bolt shaft body 1 includes a downward- expanding head at its lower end, and a cylindrical neck portion extending upward from a smaller-diameter portion of the downward-expanding head, and having the same diameter. The bolt shaft body 1 is threaded from its upper end in order to screw the nut thereon. The engaging member 2 is mounted on the cylindrical neck portion of the bolt shaft body in an expandable manner. The nut 3 is screwed on a threaded portion of the bolt shaft body 1. The thrusting member 4 thrusts the engaging member 2 by fastening the nut. The anchor bolt fixing method is carried out by forming a hole in a hard support body such as a concrete floor slab. The hole consists of a straight hole and a downward-expanding hole at a bottom end of the straight hole. Then, the anchor bolt is inserted into the hole, and the engaging member 2 mounted on the anchor bolt is thrust and expanded as it moves toward the lower end, to thereby tightly engage the engaging member with the shaft body and fix the anchor bolt in the hole. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor bolt which can be firmly fixed so as not to come off and a method of fixing the anchor bolt.

[0002]

2. Description of the Related Art Anchor bolts for mounting and supporting structures and various articles by inserting holes into a rigid support such as a concrete floor and fixing it are conventionally used by inserting an anchor bolt through a straight hole. The mainstream method is to expand the lower end of the to firmly press it against the wall surface of the hole to prevent it from coming off.

For example, in Japanese Unexamined Patent Publication No. 7-26633, a hollow cylinder is formed, an annular thin portion is provided in the middle of the side wall thereof, and a taper that spreads outward from the thin portion toward the outer end. A screw having a surface formed therein and a taper portion that is inserted into the outer insertion cylinder and has one side portion with a taper portion whose inclination is substantially the same as that of the tapered surface, and the other side portion with which the mounting female screw body is screwed. An anchor bolt having a screw rod having a threaded portion is disclosed. The anchor bolt is inserted into an embedding hole formed in a hard support, and a taper portion of an insertion cylinder is tightened by tightening a mounting screw body. It is designed to be expanded by the taper part of the screw rod and pressed against the wall surface of the embedding hole to be fixed.

Further, in Japanese Unexamined Patent Publication No. 9-209457, a cone having two tapered surfaces with different inclination angles is formed at the tip of the anchor body, and the cone is attached around the cone to provide the above-mentioned 2 A post-construction anchor composed of a wedge portion that abuts a taper surface having a large inclination angle among the tapered surfaces of the step and an expansion plate that includes a shell portion that abuts a taper surface having a small inclination angle is disclosed. After inserting the construction anchor into the fixing hole opened in the concrete base material, the wedge part is locked to the wall surface of the fixing hole by exerting a pulling action on the anchor body, and the shell part is firmly pressed against the wall surface to fix it. A fixing method of doing so is disclosed.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The embedding hole for inserting and fixing an anchor bolt in Japanese Patent No. 33, and the fixing hole for inserting and fixing a post-installed anchor in Japanese Unexamined Patent Publication No. 9-209457 are straight straight lines that have not been penetrated. It is fixed with a large hole, and there is a risk that it will come off against a strong tensile force. In JP-A-9-209457,
The shell part is strongly pressed against the wall surface of the hole by the pulling action, and the wedge part bites into the wall surface of the hole.However, it is strong against earthquakes etc. when mounting large-scale structures such as bridges and plants. There is a problem that the durability is not sufficient when subjected to repeated tensile force.

When the anchor bolt is subjected to a strong repetitive tensile force, the wall surface of the hole of the support may be rubbed and damaged or deformed, and the hole cannot be reused. There is a problem that it itself is easily damaged. SUMMARY OF THE INVENTION An object of the present invention is to provide an anchor bolt and a method of fixing the anchor bolt made in view of these problems.

[0007]

In order to achieve the above object, the present invention has taken the following means. That is, (1) a taper-shaped head with a downward expansion is formed at the lower end, and a cylindrical neck is formed with the same outer diameter upward from the small-diameter portion of the tapered head, and screwing is performed to screw the nut from the upper end. The bolt shaft body, the engaging member which is mounted on the cylindrical neck portion of the bolt shaft body so as to be able to open and expand, and the nut is screwed into the threaded portion of the bolt shaft body, and the engaging member is tightened by the nut. And an engaging member extruded by the extruding member, which is configured to be expanded and expanded in a downwardly expanding taper shape. (2) A cylinder in which an engaging member mounted on the cylindrical neck portion of the bolt shaft body so as to be able to open and close is fitted into the cylindrical neck portion of the bolt shaft body and has an outer diameter larger than the screw outer diameter of the bolt shaft body. -Shaped, the groove is formed in the outer periphery of the upper end, and the circumference is equally divided into a plurality of parts, and an elastic ring is fitted into the groove so that it can be opened and expanded to surround the cylindrical neck portion of the bolt shaft body. The anchor bolt according to the above (1), which is mounted so that (3) By screwing the nut into the threaded portion of the bolt shaft,
An extruding member for extruding the engaging member by tightening the nut is provided at two positions with the concave groove in the circumferential longitudinal direction of the bolt shaft body at the relative positions, and the extruding plate is fitted into each of the concave grooves, and the nut is inserted. The anchor bolt according to the above (1) or (2), wherein the anchor bolt is configured to be pushed by pushing the extrusion plate by tightening. (4) Two positions are provided between the upper end surface of the extruding plate and the lower surface of the nut so as to have an inner diameter that allows the screw portion of the bolt shaft body to penetrate therethrough and be located at relative positions in the circumferential longitudinal direction of the bolt shaft body. With a spacer provided with a tongue that engages with the groove,
Between the lower end surface of the push-out plate and the upper surface of the engaging member, an inner diameter is fitted to the cylindrical neck portion of the bolt shaft body, and a spacer having an outer diameter substantially equal to the outer diameter of the engaging member is interposed. The anchor bolt according to item (3) above. (5) Screw the nut into the threaded portion of the bolt shaft,
Extruding member that pushes out the engaging member by tightening the nut is provided in two places with the groove in the longitudinal direction of the circumference of the bolt shaft relative to each other, and in the inner hole of the extrusion pipe through which the bolt shaft can penetrate. A rib that engages with the recessed groove is provided, the rib is fitted into the bolt shaft body, and the push-out pipe is pushed by tightening the nut to push out the engaging member. (1) or It is the anchor bolt according to the above item (2).

(6) Then, a taper-shaped head portion having a downward spread and a cylindrical neck portion having the same outer diameter are formed above the small diameter portion of the taper-shaped head portion at the lower end portion, and a nut is screwed from the upper end portion. A bolt shaft body that has been screwed appropriately, an engagement member that is mounted on the cylindrical neck portion of the bolt shaft body so that it can be opened and expanded, and a nut is screwed into the threaded portion of the bolt shaft body. Anchor bolts provided with an extruding member for extruding the engaging member by tightening, a straight hole in the hard support, and insert a taper hole of a downward spread at the lower end of the straight hole, A method for fixing an anchor bolt, in which the nut is tightened to push the pushing member to push the engaging member to open and expand the engaging member into a taper shape of the downward expansion, and to tightly engage and fix the tapered hole of the downward expansion. Got .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings showing an embodiment. As shown in FIG. A cylindrical neck portion 1b having the same outer diameter is formed upward from a small diameter portion, and a bolt shaft body 1 is threaded to screw a nut from above, and a cylindrical neck portion 1b of the bolt shaft body is openable and expandable. And a push-out member 4 in which a nut 3 is screwed into the threaded portion of the bolt shaft 1 and the engagement member 2 is pushed out by tightening the nut. .

As shown in FIG. 2, the bolt shaft body 1 has a downwardly expanding tapered head portion 1a and a cylindrical neck portion 1b having the same outer diameter upward from the small diameter portion of the tapered head portion. , Screwing is performed to screw the nut from above, and the groove 1c is located at two relative positions in the circumferential longitudinal direction of the bolt shaft 1 (one position on the opposite back surface is not shown). ) It is provided. In the embodiment, screwing is performed from the upper side of the bolt shaft body 1 to the boundary region of the cylindrical neck portion 1b in the lower portion, but the screwing is sufficient to screw and fix the nut from above. It only needs to be applied to the area.

The engaging member 2 has an inner diameter hole 2 as shown in FIG.
a is fitted in the columnar neck portion 1b of the bolt shaft body 1, the outer diameter 2b is formed in a cylindrical shape larger than the screw outer diameter of the bolt shaft body 1, and a groove 2c is formed in the outer peripheral portion of the upper end and The circumference is divided into a plurality of parts (4 in the embodiment shown in FIG. 3), and the concave groove 2c is formed.
As shown in FIG. 1, a stretchable elastic ring 5 is fitted into the bolt shaft 1 so as to open and expand, and is mounted so as to surround the cylindrical neck portion 1b of the bolt shaft body 1. As the elastic ring 5, it is preferable to use a commercially available rubber O-ring.

The pushing member 4 is formed in two concave grooves 1c at relative positions in the circumferential direction of the circumference of the bolt shaft body 1 as shown in FIG.
The pushing member 4 is pushed by tightening the nut 3 to push out the engaging member 2 as shown in FIG. 3, and the spacer 6 is interposed between the upper end surface of the pushing plate 4A and the lower surface of the nut 3. Then, the spacer 6 is formed into an inner diameter hole 6a through which the screw portion of the bolt shaft body 1 can pass, as shown in FIG.
By providing the tongue pieces 6b, 6b in the inner diameter hole so as to engage with the concave grooves 1c provided at two positions at relative positions in the longitudinal direction of the circumference of the bolt shaft body 1, the extrusion plate 4A works well by tightening the nut 3. It is pushed. The outer diameter of the spacer 6 is larger than the outer diameter of the screw of the bolt shaft body 1, but is large enough to be inserted into a hole opened for fixing the anchor bolt.

Further, a spacer 7 is interposed between the lower end surface of the push-out plate and the upper surface of the engaging member 2, and the spacer 7 is fitted into the cylindrical neck portion 1b of the bolt shaft body 1 in inner diameter. The outer diameter is set to be substantially the same as the outer diameter of the engaging member 2, and the circumference of the engaging member 2 is evenly contacted with the upper surface of the engaging member 2 and is uniformly extruded.

The extruding member 4 is not the extruding plate 4A as described above, but ribs 4b and 4b are provided in the inner diameter hole 4a of the extruding pipe 4B as shown in FIG.
Concave groove 1c provided at two positions relative to each other in the circumferential longitudinal direction of
If the nut 3 and the engaging member 2 are fitted so as to engage with each other, the engaging member 2 can be pushed out by tightening the nut 3. The extruded pipe 4B is a thin extruded pipe that can be inserted into a gap between the screw outer diameter of the bolt shaft 1 and a hole formed for fixing the anchor bolt.

Then, by pushing the pushing member 4 by tightening the nut 3 and pushing the engaging member 2, the engaging member 2 is pushed from the cylindrical neck portion 1b of the bolt shaft body 1 to the tapered head portion 1a, The inner diameter 2a of the engaging member 2 is expanded by the tapered surface of the tapered head 1a, so that the engaging member 2 has a downwardly expanding taper shape.

Next, fixing the anchor bolts constructed as described above to a hard support such as a concrete floor will be described with reference to FIGS. 7 to 9. First, as shown in FIG. 7, a straight hole 9 is formed in a support 8 such as a concrete floor, and a downwardly expanding tapered hole 9a is formed in the lower end portion of the straight hole. The inner diameter of the straight hole 9 is made larger than the screw outer diameter of the bolt shaft body 1 by about 1.5 to 3 mm in accordance with the bolt shaft body 1 of the anchor bolt to be fixed. The conical hole 9b at the lower end is a hole trace due to the cone angle of the tip of the drill when the straight hole 9 is drilled, and is not particularly required for drilling according to the present invention.

Next, the anchor bolt according to the present invention is
When inserted into the straight holes 9 and the tapered holes 9a formed in the support 8 as described above, the state shown in FIG. 8 is obtained. When the nut 3 is tightened in this state, the pushing members 4 and 4 are pushed downward via the spacer 6 and the engaging member 2 is pushed downward via the spacer 7.

The engaging member 2 has a complicatedly divided circumference,
Bolt shaft 1 that can be opened and expanded by elastic ring 5
Since it is attached to the columnar neck portion 1b of the above, when it is extruded downward by the pushing member 4 through the spacer 7, the taper surface of the tapered head portion 1a at the lower end portion opens and expands in a downwardly expanding taper shape. As shown in FIG. 9, the engaging member 2 is completely and tightly engaged with the tapered hole 9a, the anchor bolt is firmly fixed to the support 8, and the durability is maintained against a strong tensile force. Note that, in FIG. 9 of the present embodiment, the nut 3 is brought into contact with the support surface of the support body 8 and tightened, but when supporting and fixing an object to be supported, the support surface of the support body 8 and the nut 3 are It is assumed that the nut 3 is tightened with a supported object interposed therebetween.

The outer diameter of the screw of the bolt shaft body 1 of the anchor bolt and the inner diameter of the straight hole 9 of the support 8 are 1.5 to 10.
Since a gap of about 3 mm is provided, a tapered head 1a at the lower end of the bolt shaft body 1 is tapped into a tapered hole 9a in which the hole 9 and the small-diameter portion are formed to expand downward with the same diameter. In order to tightly engage the outer diameter of the engaging member 2, the outer diameter of the engaging member 2 in a state in which it is attached to the cylindrical neck portion 1b of the bolt shaft 1 and is not expanded is determined by using the screw of the bolt shaft 1. By making the inside diameter of the engaging member 2 larger than the outside diameter within the range of the gap, the inside diameter portion of the engaging member 2 can be appropriately closely engaged without being displaced from the tapered surface of the tapered head 1a.

[0020]

As described above, according to the present invention, a rigid support such as a concrete floor is provided with a straight hole and a downwardly-extending tapered hole at the lower end of the straight hole. The anchor bolt is fixed in the taper hole by opening the engaging member attached to the lower end of the anchor bolt in a taper shape that spreads downward and tightly engaging it, so a strong tensile force acts. Even if it is, it can be firmly fixed without coming off due to the taper tight engagement, and it is effective in maintaining durability against strong repeated tensile forces such as earthquakes when mounting and supporting large-scale structures such as bridges and plants. Play.

Further, the taper hole provided at the lower end portion of the straight hole and the engaging member provided at the lower end portion of the anchor bolt are expanded in a taper shape to be completely in close contact with each other, whereby the wall surface of the hole is It is possible to prevent it from being scratched and scratched or deformed, and it is also possible to prevent the anchor bolt itself from being damaged.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an anchor bolt according to the present invention.

FIG. 2 is a perspective view of a bolt shaft body.

FIG. 3 is a perspective view of an engaging member.

FIG. 4 is a perspective view when the extruding member is an extruding plate.

FIG. 5 is a perspective view of a spacer interposed between the nut and the upper end surface of the extrusion plate when the extrusion member is the extrusion plate.

FIG. 6 is a perspective view when the extruding member is an extruding pipe.

FIG. 7 is a vertical cross-sectional view showing an embodiment of holes for fixing anchor bolts to a support.

8 is a vertical cross-sectional view showing a state in which an anchor bolt is inserted into the hole shown in FIG.

FIG. 9 is a vertical cross-sectional view showing a state where anchor bolts are fixed.

[Explanation of symbols]

1 bolt shaft 1a Tapered head 1b cylindrical neck 1c, 2c concave groove 2 Engagement member 2a, 4a, 6a Inner hole 2b outer diameter 3 nuts 4 Extruded member 4A extrusion plate 4B extruded pipe 4b rib 5 elastic ring 6,7 Geza 6b tongue 8 support 9 holes 9a Taper hole 9b conical hole

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2D046 AA03                 2E125 AA76 AF01 AF07 AG10 AG13                       BA12 BA18 BA22 BA33 BB08                       BB28 BC09 BD01 BE07 BE08                       BF01 CA05 CA14 EA01                 3J025 AA07 BA06 CA03 CA06 EA01

Claims (6)

[Claims] 1. A downwardly expanding tapered head portion and a columnar neck portion having the same outer diameter are formed upward from a small diameter portion of the tapered head portion at a lower end portion, and screwing is performed to screw a nut from an upper end portion. A bolt shaft body that has been applied, an engagement member that is attached to the cylindrical neck portion of the bolt shaft body so as to open and expand, and a nut is screwed into the threaded portion of the bolt shaft body, and is engaged by tightening the nut. An anchor bolt, comprising: an extruding member adapted to extrude the member, wherein the engaging member extruded by the extruding member is expanded and expanded in a downwardly expanding taper shape. 2. An engagement member, which is attached to a cylindrical neck portion of a bolt shaft body so as to open and expand, has an inner diameter fitted to the cylindrical neck portion of the bolt shaft body, and an outer diameter of the screw shaft outer diameter of the bolt shaft body. It is formed in a large cylindrical shape, and a groove is provided on the outer periphery of the upper end, and the circumference is equally divided into a plurality of parts, and a stretchable elastic ring is fitted into the groove to open and expand the bolt shaft body. The anchor bolt according to claim 1, wherein the anchor bolt is mounted so as to surround the columnar neck portion. 3. An extruding member in which a nut is screwed into a threaded portion of a bolt shaft body to extrude an engaging member by tightening the nut, and a recess groove is formed in the circumferential direction of the bolt shaft body. 2. Positions are provided at two locations, and push-out plates are fitted into the recessed grooves, respectively, and the push-out plates are pushed by tightening the nuts to push out the engaging members. The anchor bolt described in 2. 4. An internal diameter that allows the screw portion of the bolt shaft body to penetrate therethrough between the upper end surface of the extrusion plate and the lower surface of the nut, and two positions are provided at relative positions in the circumferential longitudinal direction of the bolt shaft body. With a spacer provided with a tongue that engages with the recessed groove, the inner diameter is fitted to the cylindrical neck of the bolt shaft between the lower end surface of the extrusion plate and the upper surface of the engaging member. The anchor bolt according to claim 3, wherein a spacer having an outer diameter substantially the same as the outer diameter of the engaging member is interposed. 5. An extruding member in which a nut is screwed into a threaded portion of a bolt shaft body to extrude an engaging member by tightening the nut, and a recessed groove is formed in the circumferential direction of the bolt shaft body. Positioned in two places, a rib that engages the concave groove is provided in the inner diameter hole of the extrusion pipe through which the bolt shaft can penetrate, and it is inserted into the bolt shaft, and the nut is tightened to push the extrusion pipe to engage. The anchor bolt according to claim 1 or 2, wherein the anchor bolt is configured to extrude the member. 6. A downwardly expanding tapered head portion and a cylindrical neck portion having the same outer diameter are formed above a small diameter portion of the tapered head portion at a lower end portion, and screwing is performed to screw a nut from an upper end portion. A bolt shaft body that has been applied, an engagement member that is attached to the cylindrical neck portion of the bolt shaft body so as to open and expand, and a nut is screwed into the threaded portion of the bolt shaft body, and is engaged by tightening the nut. An anchor bolt having an extruding member adapted to extrude a member is inserted into a hard support by forming a straight hole and a taper hole of a downward expansion at the lower end of the straight hole, and tightening the nut. A method for fixing an anchor bolt, characterized in that the pushing member pushes the engaging member to push the engaging member, the engaging member is opened and expanded into a tapered shape with a downward expansion, and the engaging hole is closely engaged with and fixed to the tapered hole with a downward expansion. .