JP2007198572A - Metal spreading anchor, and construction method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a technique capable of improving the shear rigidity of a metal spreading anchor by suppressing bending deformation of the anchor caused by shearing force acting on the anchor from an attachment fixed to a base material by using the anchor. <P>SOLUTION: In the metal spreading anchor 11, and its construction method, hole wall abutting parts 14e, 14f kept in direct contact with an inner wall surface 113 of a prepared hole 111 protrude from an outer circumference of an anchor body 14 having a spreading part 12 to be spread in the prepared hole 111 in a tip. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a metal expansion anchor and a metal expansion anchor construction method, and more particularly to a metal expansion anchor and a metal expansion anchor construction method capable of improving the shear rigidity of the anchor.

  Conventionally, metal expansion anchors are frequently used as anchors used for fixing attachments (including panels, sheets, etc.) to a base material such as a concrete frame, and for interlaminar bonding of base materials composed of multiple layers. . The metal expansion anchor is fixed to the base material by inserting the metal expansion anchor into a prepared hole drilled in a base material such as a concrete frame and expanding a tip end portion (expansion portion). As this metal expansion anchor, there are various types such as a core rod driving type metal expansion anchor (for example, Patent Document 1), a tightening type anchor represented by a taper bolt type, a cone nut type, a wedge type and the like (for example, Patent Document 2). There is something.

FIG. 8 shows an example of fixing an attachment to a base material using a metal expansion anchor.
In FIG. 8, reference numeral 110 denotes a concrete frame (base material), 120 denotes a metal expansion anchor (hereinafter, simply referred to as an expansion anchor or an anchor), and 130 denotes an attachment.
As shown in FIG. 8, the expansion anchor 120 widely employs a structure having an expansion portion 121 on the front end side and a screw shaft portion 122 on the rear end side. Then, the expansion part 121 is expanded to be fixed to the base material 110. In addition, fixing of the attachment 130 to the base material 110 using the expansion anchor 120 is performed by passing the expansion anchor 120 through a through hole 131 formed in the attachment 130 and via the attachment 130. In general, the attachment 130 is fixed to the base material 110 by tightening the nut 140 screwed to the screw shaft portion 122 that protrudes to the opposite side to the base 110.
Reference numeral 150 denotes a washer interposed between the nut 140 and the base material 110.
JP 2005-307637 A Japanese Patent Publication No.59-30925

By the way, in the fixing of the attachment using the expansion anchor as described above, for example, the displacement force (external force) in the direction along the surface of the base material (shear direction, sliding direction) acts on the attachment. A shearing force may act on the anchor.
Needless to say, the anchor needs to have sufficient shear rigidity.
However, it is common to form the anchor preparation pilot hole formed in the base material with a diameter slightly larger (for example, 0.3 to 0.5 mm) than the anchor outer diameter, which improves shear rigidity. As a result, in some cases, anchors with a large diameter had to be used to secure the required shear rigidity.

That is, in the conventional configuration, there is a gap (reference numeral 160 in FIG. 8) between the outer surface (outer peripheral surface) of the portion other than the extended portion of the anchor and the inner wall surface of the pilot hole drilled in the base material with a diameter larger than the anchor outer diameter. Exists). In such a configuration, the shearing force acting on the anchor is bent and deformed (flexed deformation in FIG. 8) in a portion (particularly, a portion accommodated in the pilot hole) located on the rear end side from the expanded portion of the anchor. , Refer to the anchor 120 indicated by the phantom line). The shear stiffness of the anchor is given by the bending strength of the anchor.
In view of this, if an anchor having a large diameter (outer diameter) is employed, bending deformation of the anchor can be suppressed against a shear load. However, the use of an anchor having a large diameter leads to an increase in the diameter of the prepared hole and an increase in cost. An increase in the diameter of the lower hole has many disadvantages such as an increase in the drilling effort of the lower hole.
For this reason, the actual situation is that no appropriate measures exist.

  In view of the above-described problems, an object of the present invention is to provide a metal expansion anchor that can improve shear rigidity without increasing the size of the pilot hole and a method for constructing the metal expansion anchor.

In order to solve the above problems, the present invention provides the following configuration.
The invention according to claim 1 is provided with an anchor body having an extended portion at the tip which is expanded in a pilot hole drilled in a base material, and further, a position separated from the expanded portion of the anchor body toward the rear end side. A hole wall abutting portion that is accommodated in the lower hole in a state of being in direct contact with an inner wall surface of the lower hole that is provided on the outer periphery of the anchor body and has a diameter larger than that of the anchor body. A metal expansion anchor is provided.
The invention according to claim 2 provides the metal expansion anchor according to claim 1, wherein the hole wall contact portion is provided at a plurality of locations in the longitudinal direction of the anchor body.
The invention according to claim 3 is characterized in that at least one of the plurality of hole wall contact portions is formed by a protrusion protruding from the peripheral surface of the anchor body. A metal expansion anchor is provided.
According to a fourth aspect of the present invention, the hole wall contact portion is extrapolated to the rear end side of the extension portion of the anchor body and is in direct contact with the inner wall surface of the lower hole. 3. The metal expansion anchor according to claim 1, wherein the metal expansion anchor is a rigid sleeve to be accommodated.
The invention according to claim 5 further includes a nut screwed into a screw shaft portion extending from the expansion portion of the anchor body toward the rear end side, and a rear portion of the anchor body that is drilled in the anchor body. The metal expansion anchor according to any one of claims 1 to 4, further comprising: a core rod that is housed in a core rod insertion hole that opens at an end, and that expands the expansion portion by driving into the expansion portion. I will provide a.
The invention according to claim 6 is a sleeve driving type metal expansion anchor, which is a taper bolt and a tapered shape formed at the tip of the taper bolt in a pilot hole which is extrapolated to the taper bolt and drilled in the base material. The expansion sleeve is expanded by being driven into the enlarged diameter portion of the taper bolt from the rear end side thereof, and the expansion sleeve fixed to the base material is expanded. A rigid sleeve that is extrapolated from the end side and disposed on the rear end side of the expansion sleeve, and is accommodated in the lower hole in a state of being in direct contact with the inner wall surface of the lower hole; A metal expansion anchor, comprising: a nut that is screwed into a portion of the screw shaft portion on the rear end side of the taper bolt that protrudes from the opening portion of the lower hole after being housed inside. Subjected to.
The invention according to claim 7 is a tightening-type metal expansion anchor, and is a tapered shape provided at the tip of the bolt in a bolt and a pilot hole which is externally inserted into the bolt and drilled in the base material. A sleeve-like expansion portion that is expanded by being pressed into the cone portion and is fixed to the base material, and a rear end opposite to the distal end side that is inserted into the pilot hole of the bolt than the expansion portion A hole wall abutting portion which is provided integrally or separately on the outer periphery of the bolt and is accommodated in the lower hole in a state of being in direct contact with the inner wall surface of the lower hole; Provided is a metal expansion anchor comprising: a screw shaft portion provided on a rear end side; and a nut provided on a rear end side of the bolt with respect to the hole wall contact portion. .
According to an eighth aspect of the present invention, an anchor body having an expansion portion that is expanded in a pilot hole drilled in a base material is inserted into the pilot hole formed in the base material, and the expansion portion is After expanding and fixing to the base material, a rigid sleeve accommodated in the lower hole in direct contact with the inner wall surface of the lower hole formed to have a larger diameter than the anchor main body is attached to the anchor main body at the rear end. Provided is a method for constructing a metal expansion anchor that is extrapolated from the side and accommodated in the prepared hole.
The invention according to claim 9 is the construction method of the metal expansion anchor according to claim 6, wherein the anchor body formed by extrapolating the expansion sleeve to the taper bolt is inserted into a pilot hole drilled in a base material, In the state in which the enlarged diameter portion at the tip of the taper bolt is in contact with the innermost part of the lower hole, the expansion sleeve is expanded by driving into the enlarged diameter portion with a driving rod from the rear end side of the taper bolt. Is fixed to the base material, and a rigid sleeve accommodated in the lower hole in direct contact with the inner wall surface of the lower hole having a larger diameter than the anchor main body is extrapolated from the rear end side to the anchor main body. A metal expansion anchor construction method is provided, wherein the metal expansion anchor is housed in the pilot hole.

  According to the present invention, the hole wall abutting portion provided on the outer periphery of the anchor main body of the metal expansion anchor or the hole wall abutting portion (rigid sleeve) externally attached to the taper bolt of the sleeve driving type anchor is provided in the lower hole. By abutting against the wall surface, the displacement of the anchor body in the lower hole (oscillation in the lower hole; displacement in the cross-sectional direction of the lower hole) is suppressed (or prevented). As a result, even if a shearing force is applied, bending deformation of the anchor body in the prepared hole can be suppressed, and the shear rigidity of the anchor body is improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1, 2, 4, and 5, reference numeral 110 is a concrete frame (base material), 111 is a lower hole, 130 is an attachment, and 131 is a through hole formed in the attachment.

(First embodiment)
First, the construction method of the expansion anchor (metal expansion anchor) and expansion anchor of 1st Embodiment which concerns on this invention is demonstrated with reference to FIG. 1, FIG.
The expansion anchor 11 described here is a core expansion type metal expansion anchor.
FIG. 1 is a diagram showing a state in which the expansion anchor 11 is inserted into the prepared hole 111 (a state before the expansion portion 12 is expanded), and FIG. 2 is an expansion of the expansion portion 12 of the expansion anchor 11 in FIG. It is a figure which shows the state which adhered to the preform | base_material 110. FIG.
The expansion anchor 11 will be described with the lower side in FIGS. 1 and 2 as the front end side and the upper side as the rear end side.

As shown in FIGS. 1 and 2, the expansion anchor 11 includes an anchor main body 14 having a substantially round bar-like shape having an expansion portion 12 on the front end side and a screw shaft portion 13 on the rear end side, and a hole formed in the anchor main body 14. The core rod 15 is inserted into the core rod housing hole 14 a, the washer 16 is externally inserted into the anchor body 14, and the nut 17 is screwed onto the screw shaft portion 13. .
The washer 16 is interposed between a nut 17 and a hole wall contact portion 14 f (described later) that protrudes from the outer periphery of the center portion in the longitudinal direction of the anchor body 14. Since the washer 16 is formed in a ring shape having an inner diameter smaller than the outer diameter of the hole wall contact portion 14f, the washer 16 does not slip out from the hole wall contact portion 14f to the distal end side of the anchor main body 14.

  The core rod storage hole 14 a reaches the extension portion 12 through an opening portion 14 b that opens at the rear end of the anchor main body 14. The distal end portion of the core rod housing hole 14a on the side of the expansion portion 12 is formed in a tapered shape (taper portion 14c) having an inner diameter that decreases from the rear end side of the anchor body 14 toward the distal end side.

The core rod 15 is a rod-shaped body in which the driving length (the length of the rod-shaped main body 15a) stored in the anchor main body 14 is secured longer than the entire length of the core rod storage hole 14a. As shown in FIG. 1, before driving, the proximal end side where the flange-shaped head portion 15 b is formed protrudes from the core rod storage hole 14 a to the proximal end side of the anchor main body 14. As shown in FIG. 2, when the core rod 15 is driven into the anchor main body 14, the extended portion 12 divided into a plurality of parts by the split groove 12 a is a sharp portion that is a tip portion formed in a taper of the core rod 15. 16b is expanded by being pushed open.
1 illustrates the expansion anchor 11 in which the core rod 15 is inserted into the core rod storage hole 14a in advance. However, the present invention is not limited to this, and the expansion anchor 11 before the core rod 15 is inserted into the lower hole 111. It is also possible to insert and set.

Hole wall contact portions 14e and 14f, which are rib-like protrusions provided around the outer periphery of the anchor main body 14, are formed at two locations separated from the expanded portion 12 of the anchor main body 14 toward the rear end side. . The hole wall abutting portions 14 e and 14 f are projected at two locations separated from each other in the longitudinal direction of the anchor main body 14.
The hole wall abutting portions 14 e and 14 f are large-diameter portions in which the outer diameter of the anchor body 14 is increased and protruded from the peripheral surface of the anchor body 14. The outer diameters of the hole wall contact portions 14e and 14f are the same.
The anchor main body 14 is formed with an outer diameter smaller than that of the hole wall contact portions 14e and 14f except for the portion where the hole wall contact portions 14e and 14f are formed.

One of the two hole wall contact portions 14e and 14f (hole wall contact portion 14e) has a thread on the outer periphery formed between the expansion portion 12 and the screw shaft portion 13 of the anchor body 14. It is provided around the outer periphery of the intermediate sleeve portion 14d, which is a cylindrical portion that is not formed.
The other hole wall contact portion 14f is provided around the outer periphery of the anchor body 14 at a position spaced from the hole wall contact portion 14e toward the rear end side of the anchor body 14.
The screw shaft portion 13 of the anchor main body 14 is a portion extending from the hole wall contact portion 14f to the rear end side. The hole wall abutting portions 14 e and 14 f of the anchor main body 14 project between the expansion portion 12 and the screw shaft portion 13.

When the anchor body 14 is inserted into the lower hole 111, the hole wall contact portions 14 e and 14 f are accommodated in the lower hole 111 in a state of being in direct contact with the inner wall surface 113 of the lower hole 111. It plays a role of regulating the displacement of the anchor body 14 in the hole 111 (displacement in the cross-sectional direction perpendicular to the central axis of the lower hole 111).
When the hole wall contact portions 14e and 14f are accommodated in the lower hole 111, the anchor main body 14 is placed in the lower hole 111 in a state where the center axis of the anchor main body 14 is aligned with the center of the cross section of the lower hole 111. Placed in.

Next, an operation for fixing the attachment 130 to the base material 110 using the expansion anchor 11 will be described.
In the base material 110, as usual, the outer diameter D of the anchor body 14 (the outer diameter of the portion other than the hole wall contact portions 14e and 14f) is slightly larger (for example, 0.3 to 0.5 mm). The lower hole 111 is drilled with a hole diameter φ. The expansion anchor 11 employed here is one in which the outer diameters of the hole wall contact portions 14e and 14f are aligned with the drilling diameter φ.
The expansion anchor 11 is an attachment in which the anchor main body 14 passed through the attachment 130 through the through hole 131 of the attachment 130 is inserted into the lower hole 111 from the distal end side, and the washer 16 is brought into contact with the base material 110. The object 130 is sandwiched between the surface opposite to the base material 110 and the nut 17.

The embedding depth to be inserted into the prepared hole 111 of the expansion anchor 11 (specifically, the anchor main body 14) can be adjusted by the screwing position of the nut 17 in the screw shaft portion 13.
Here, the embedding depth of the expansion anchor 11 is such that the hole wall abutment located on the rear end side of the anchor main body 14 out of the two hole wall abutting portions 14e and 14f projecting from the outer periphery of the anchor main body 14. It adjusts so that the part 14f may be accommodated in the opening part 112 of the lower hole 111 opened to the base material 110 surface.
However, the embedding depth is preferably such that the entire hole wall contact portion 14f is accommodated in the lower hole 111 and does not protrude from the lower hole 111 to the surface of the base material 110. Thereby, it is avoided that the shear force from the attachment 130 acts directly on the hole wall contact portion 14f, and the shear force acting on the screw shaft portion 13 from the attachment 130 is borne by the entire expansion anchor 11. .

When the insertion of the anchor body 14 into the lower hole 111 is completed, the core 15 is struck from the rear end side (head 16b side) using a hammer or the like and driven into the anchor body 14 to expand the expansion portion 12, The anchor body 14 is fixed to the base material 110.
Thereby, the attachment 130 is fixed to the base material 110.

  According to the expansion anchor 11, the hole wall contact portion 14 e that directly contacts the inner wall surface 113 of the lower hole 111, even if a shearing force is applied from the attachment 130 fixed to the base material 110 using the expansion anchor 11. The bending deformation of the anchor main body 14 is suppressed by 14f. For this reason, the shear rigidity of the expansion anchor 11 is improved.

In this embodiment, the configuration in which the hole wall abutting portions 14e and 14f are provided to project at two positions separated from each other in the longitudinal direction of the anchor main body 14 is illustrated, but the present invention is not limited to this, and the anchor main body is not limited thereto. It is also possible to adopt a configuration in which the hole wall abutting portion is protruded at one place in the longitudinal direction, or at three places or more. However, in the case where the hole wall contact portion is provided only at one position in the longitudinal direction of the anchor body, the opening 113 of the lower hole 111 or the position close to the opening 113 as much as possible is accommodated in the lower hole 111. Adjusting the installation position is advantageous in terms of improving shear rigidity.
1 and 2 exemplify rib-shaped protrusions (lateral ribs) provided around the entire outer periphery of the anchor main body 14 as the hole wall contact portion. For example, as shown in FIG. 3 (a), protrusions 14g (protrusions) projecting at a plurality of positions on the outer periphery of the anchor body 14 at intervals, as shown in FIG. Elongate longitudinal ribs along the direction). Further, as shown in FIG. 3 (b), a structure in which a sleeve 14h (for example, a metal sleeve, a rigid sleeve) is fixed to the outer periphery of the anchor main body 14 and functions as a hole wall contact portion can be adopted. It is.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
The expansion anchor 21 described here is a sleeve driving type metal expansion anchor.
4 is a view showing a state in which the expansion anchor 21 is inserted into the prepared hole 111 (a state before the expansion portion is expanded), and FIG. 5 is an expansion of the expansion portion of the expansion anchor 21 in FIG. It is a figure which shows the state adhering to the material 110. FIG.
The expansion anchor 21 will be described with the lower side in FIG. 4 and FIG. 5 as the front end side and the upper side as the rear end side.

As shown in FIGS. 4 and 5, the expansion anchor 21 includes a taper bolt 22 having a diameter-enlarged portion 221 having a shape obtained by enlarging the screw shaft portion 222 at the tip of a screw shaft 222 (hereinafter referred to as a screw shaft portion). The expansion sleeve 23 inserted on the taper bolt 22, the rigid sleeve 24, the washer 25 and the spring washer 26 inserted on the taper bolt 22 on the rear end side of the expansion sleeve 23, and the taper bolt 22 are screwed. The configuration includes a nut 27.
The taper bolt 22 in the illustrated example has a configuration in which the entire portion other than the enlarged diameter portion 221 is a screw shaft portion 222, but the screw shaft portion 222 may be configured only in the rear end portion of the taper bolt 22. good.

The rigid sleeve 24, washer 25, and spring washer 26 are expanded by striking the expansion sleeve 23 into the tapered diameter-enlarged portion 221 at the tip of the taper bolt 22 within the lower hole 111 (specifically, the distal end side of the expansion sleeve 23. After the expansion portion 231 is expanded) and fixed to the base material 110, the taper bolt 22 is extrapolated from the rear end side.
The rigid sleeve 24 is extrapolated to the taper bolt 22 and accommodated in the opening 113 of the lower hole 111.
The washer 25 and the spring washer 26 are extrapolated to the taper bolt 22 and arranged on the side opposite to the base material 110 of the attachment 130.
The nut 27 is screwed onto the screw shaft portion 222 from the rear end side of the taper bolt 22 after the rigid sleeve 24, the washer 25, and the spring washer 26 are extrapolated to the taper bolt 22 after the expansion of the expansion sleeve 23 is completed. By tightening the nut 27, the attachment 130 is fixed so as to be pressed against the base material 110 by the pressing force from the nut 27 transmitted through the washer 25 and the spring washer 26.

The distal end portion of the expansion sleeve 23 is divided into a plurality of parts by the split groove 232, and constitutes an expanded portion 231 that is expanded by being driven into the enlarged diameter portion 221 at the distal end of the taper bolt 22.
The enlarged diameter portion 221 is formed in a tapered shape whose diameter increases from the rear end side to the front end side of the taper bolt 22, and the expansion sleeve 23 is driven into the enlarged diameter portion 221 from the rear end side of the taper bolt 22. Thus, the extended portion 231 at the tip is expanded.
Further, the expansion sleeve 23 has an appropriate length in consideration of the embedding length accommodated in the lower hole 111 of the taper bolt 22 and securing the space for accommodating the rigid sleeve 24 in the lower hole 111. Use one. When the driving of the expansion sleeve 23 into the expanded diameter portion 221 is completed (see FIG. 5), the entire rigid sleeve 24 that is extrapolated to the taper bolt 22 and is disposed at a position separated from the expansion sleeve 23 toward the rear end side of the expansion anchor 21. Is stored in the lower hole 111.

The rigid sleeve 24 is formed of a highly rigid material such as metal.
The rigid sleeve 24 functions as a hole wall contact portion according to the present invention.
The inner diameter of the rigid sleeve 24 is aligned with the outer diameter of the screw shaft portion 222, and the outer diameter of the rigid sleeve 24 is slightly larger than the outer diameter of the expansion sleeve 23 (for example, 0.2 to 2.0 mm). Are aligned with the diameter (inner diameter) of the prepared lower hole 111. For this reason, the rigid sleeve 24 is accommodated in the lower hole 111, thereby controlling the displacement of the taper bolt 22 in the lower hole 111 (displacement in the cross-sectional direction perpendicular to the central axis of the lower hole 111). Fulfill.

Next, an operation for fixing the attachment 130 to the base material 110 using the expansion anchor 21 (a method for constructing the metal expansion anchor) will be described.
A lower hole 111 is drilled in the base material 110 with a drilling diameter φ2 slightly larger than the outer diameter D2 of the outer diameter of the expansion sleeve 23 (for example, 0.2 to 2.0 mm).
Next, after cleaning the inside of the lower hole 111, an anchor main body 21 </ b> A formed by extrapolating the expansion sleeve 23 to the taper bolt 22 is inserted into the lower hole 111 from the distal end side.
At this time, the anchor main body 21A inserted into the prepared hole 111 is not provided with the rigid sleeve 24, the washer 25, the spring washer 26, and the nut 27.

Next, a taper bolt in which the expansion sleeve 23 of the anchor main body 21A inserted into the lower hole 111 is abutted against the innermost part of the lower hole 111 which is a non-through hole using a sleeve-shaped driving rod 28 (see FIG. 4). 22 is expanded by driving into the enlarged diameter portion 221 at the tip. Thereby, the anchor main body 21 </ b> A is fixed to the base material 110.
The driving rod 28 is inserted into a gap between the inner wall surface 113 of the lower hole 111 and the screw shaft portion 222 of the taper bolt 22 extending from the rear end of the expansion sleeve 23.

When the anchor main body 21 </ b> A is fixed to the base material 110, the rigid sleeve 24 is extrapolated from the rear end to the taper bolt 22 and pushed into the lower hole 111.
The rigid sleeve 24 is preferably housed in the opening 112 of the lower hole 111 (or in a position as close as possible to the opening 112 in the lower hole 111) from the viewpoint of improving the shear rigidity of the expansion anchor 21.
The rigid sleeve 24 accommodated in the lower hole 111 is press-fitted into a gap between the inner wall surface 113 of the hole 111 and the threaded shaft portion 222 of the taper bolt 22 extending from the rear end of the expansion sleeve 23. Although the storage position in the lower hole 111 is not easily removed, a shift in the storage position may be prevented by fixing the taper bolt 22 with an adhesive or the like.

  When the rigid sleeve 24 is accommodated in the lower hole 111, the attachment 130, the washer 25, and the spring washer 26 are extrapolated to the screw shaft portion 222 of the taper bolt 22 protruding from the lower hole 111 to the outside of the base material 110. The nut 27 is screwed onto the shaft portion 222 and tightened. Thereby, the attachment 130 is fixed so as to be pressed against the base material 110 by the pressing force from the nut 27 acting via the washer 25 and the spring washer 26.

  In this embodiment, even if shear force acts on the expansion anchor 21 from the attachment 130 fixed to the base material 110, the rigid sleeve 24 that functions as a hole wall contact portion that directly contacts the inner wall surface 113 of the lower hole 111, Since the bending deformation of the anchor main body 21A (specifically, the taper bolt 22) is suppressed, the shear rigidity of the expansion anchor 21 is improved.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG.
Here, a wedge-type metal expansion anchor (hereinafter also referred to as an expansion anchor) will be described as an example in which the present invention is applied to a tightening-type metal expansion anchor.
FIG. 6 shows a state in which the expansion anchor 31 inserted into the prepared hole 111 is fixed to the base material 110 by a solid line. In FIG. 6, the phantom line indicates a state before the expansion portion of the expansion anchor 31 inserted into the prepared hole 111 is expanded.
The expansion anchor 31 will be described with the lower side in FIG. 6 as the front end side and the upper side as the rear end side.

  The expansion anchor 31 includes a bolt 32, a sleeve-like expansion portion 33 that is externally inserted into the bolt 32, and a screw shaft that is formed on the rear end side opposite to the front end side that is inserted into the lower hole 111 of the bolt 32. A nut 34 screwed to the portion 321, and a washer 35 and a spring washer 36 that are externally attached to the screw shaft portion 321 and are provided closer to the distal end side of the bolt 32 than the nut 34 are configured. .

The bolt 32 has a rod-like bolt main body 322 having a screw shaft portion 321 formed on the rear end side, and is thinner than the bolt main body 322 (less than the outer diameter of a portion excluding a hole wall contact portion 326 described later). The neck portion 323 is formed in a thin (shaft) shaft shape and protrudes from the tip of the bolt main body portion 322, and the tapered cone portion 324 is formed at the tip of the neck portion 323.
The tip of the bolt main body 322 has a step with the neck 323.
The cone portion 324 is a portion in which the tip of the neck portion 323 is formed thick, and is formed in a tapered shape having a smaller diameter on the side closer to the bolt main body portion 322 and a larger diameter on the portion farther from the bolt main body portion 322.
The extension portion 33 is externally attached to the neck portion 323. The expanded portion 33 has the same outer diameter as the outer diameter of the bolt main body portion 322 (the outer diameter D3 of a portion excluding a hole wall contact portion 326 described later. The same applies hereinafter). In addition, the inner diameter of the expansion portion 33 is smaller than the maximum outer diameter of the cone portion 324. For this reason, the extension part 33 is prevented from coming off from the bolt 32 by the tip part (stopper part 325) and the cone part 324 of the bolt main body part 322.

When the nut 34 of the expansion anchor 31 inserted and set in the pilot hole 111 is tightened as shown in FIG. 6, the cone portion 324 is pushed into the expansion portion 33 to expand the expansion portion 33.
The expansion anchor 31 is inserted into the through hole 131 of the attachment 130, the distal end side is inserted into the lower hole 111, and the nut 34 is tightened with the washer 35 in contact with the attachment 130. The expanded portion 33 is expanded and fixed to the base material 110. The spring washer 36 is interposed between the washer 35 and the nut 34.

The hole wall abutting portion 326 is a projecting portion (projected) on the outer peripheral surface of the bolt main body portion 322 at a position spaced from the neck portion 323 toward the rear end side of the bolt 32.
As is conventional, the pilot hole 111 formed in the base material 110 when the expansion anchor 31 is constructed is formed with an inner diameter φ3 that is slightly larger than the outer diameter D3 of the bolt main body 322.
The hole wall contact portion 326 is accommodated in the lower hole 111 in a state of being in direct contact with the inner wall surface 113 of the lower hole 111.
The hole wall contact portion 326 may be, for example, a plurality of protrusions as illustrated in FIG. 3 in addition to a rib shape (FIG. 6) extending over the entire outer periphery of the bolt main body portion 322. .
Further, the hole wall contact portion 326 may be a rigid sleeve (hole wall contact portion separate from the bolt) that is externally attached to the bolt main body portion 322 and fixed to the bolt main body portion 322.

  Also in this embodiment, even if a shearing force is applied to the extension anchor 31 from the attachment 130 fixed to the base material 110, the anchor (specifically, the anchor (specifically, the inner wall 113) is in contact with the inner wall 113 of the lower hole 111. Since the bending deformation of the bolt 32) is suppressed, the shear rigidity of the expansion anchor 31 is improved.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG.
In the fourth embodiment, an example in which a rigid sleeve is applied as a hole wall contact portion to a core rod driving type metal expansion anchor (hereinafter also referred to as an expansion anchor) will be described.
In the expansion anchor 41 shown in FIG. 7, the hole wall contact portion 14 f of the anchor body 11 of the expansion anchor 11 of the first embodiment is omitted, and the hole located between the hole wall contact portion 14 f and the expansion portion 12. An anchor main body 42 having a structure in which the entire rear end side from the wall contact portion 14e is a screw shaft portion 43 is employed. Further, as the hole wall contact portion, a rigid sleeve 44 that is externally inserted into the screw shaft portion 43 of the anchor main body 42 is employed.
The configuration of the expansion anchor 41 other than the anchor main body 42 is the same as that of the expansion anchor 11 of the first embodiment, and common portions are denoted by common reference numerals and description thereof is omitted.
Further, in the anchor main body 42, the same reference numerals are given to the portions common to the anchor main body 11 of the expansion anchor 11 of the first embodiment, and description thereof is omitted.

The expansion anchor 41 includes a rigid sleeve 44 that is externally inserted into the screw shaft portion 43 from the rear end side of the anchor main body 42, between the outer peripheral surface of the anchor main body 42 (specifically, the screw shaft portion 43) and the inner surface of the lower hole 111. By interposing in the gap, the rigid sleeve 44 can function as a hole wall contact portion, and the shear rigidity of the anchor can be increased.
The operation of extrapolating the rigid sleeve 44 to the screw shaft portion 43 may be performed before the expansion anchor 41 is inserted into the lower hole 111 or after it is inserted into the lower hole 111.

The rigid sleeve 44 is accommodated so as to be fitted into the lower hole 111, so that no positional deviation occurs in the lower hole 111.
According to the expansion anchor 41, the hole sleeve contact portion has a large degree of freedom in setting the position of the anchor main body 42 in the longitudinal direction of the rigid sleeve 44 that is extrapolated to the anchor main body 42 (specifically, the screw shaft portion 43). There is an advantage that the position can be set according to the embedding depth of the expansion anchor 41 with respect to the base material 110 at the construction site.
It should be noted that the storage position in the lower hole 111 of the rigid sleeve 44 is preferably such that a large distance from the expansion portion 12 can be secured (however, the whole is stored in the lower hole 111 and does not protrude from the lower hole 111). For example, the opening 112 of the pilot hole 111 or the vicinity thereof is preferable.

In this expansion anchor 41 as well, the hole wall contact portion 14e is fixed to, for example, a protrusion 14g as illustrated in FIGS. 3A and 3B, or an anchor body, in addition to the rib-shaped protrusion. The fact that the sleeve 14h and the like can be adopted is the same as in the first embodiment.
Further, in the expansion anchor 41, the hole wall contact portion 14e can be omitted.

A configuration in which a rigid sleeve that is separate from the anchor is extrapolated to the expansion anchor and interposed in the gap between the inner surface of the lower hole and the outer surface of the expansion anchor, and functions as a hole wall contact portion. The present invention is not limited to a drive-in anchor, and can be applied to, for example, a tightening-type metal expansion anchor.
For example, instead of the hole wall contact portion 326 of the expansion anchor 31 of the above-described fourth embodiment, a rigid sleeve extrapolated to the bolt main body portion 322 may function as the hole wall contact portion.

The metal expansion anchor of the tightening method to which the present invention is applied is not limited to the wedge type, and may be a taper bolt type, for example.
The present invention can be applied to various types of metal expansion anchors other than the above-described driving type metal expansion anchors, such as the core rod driving type and sleeve driving type, and the tightening type metal expansion anchors.

It is a figure which shows the expansion anchor of 1st Embodiment of this invention, Comprising: It is sectional drawing which shows the state which inserted the anchor main body into the pilot hole drilled in the base material. It is sectional drawing which shows the state which expanded the expansion part of the expansion anchor of FIG. 1, and fixed the anchor main body to the base material. (A), (b) is a figure which shows another aspect of the hole wall contact part applicable to the expansion anchor of 1st Embodiment of this invention. It is a figure which shows the expansion anchor of 2nd Embodiment of this invention, Comprising: It is sectional drawing which shows the state which inserted the anchor main body into the pilot hole drilled in the base material. FIG. 5 is a cross-sectional view illustrating a state in which an expansion portion of the expansion anchor of FIG. 4 is expanded and the anchor body is fixed to a base material. It is a figure which shows the expansion anchor of 3rd Embodiment of this invention, Comprising: It is sectional drawing which shows the state which expanded the expansion part and was fixed to the base material. It is a figure which shows the expansion anchor of 4th Embodiment of this invention, Comprising: It is sectional drawing which shows the state which expanded the expansion part and was fixed to the preform | base_material. It is sectional drawing which shows the state which fixed the attachment to the base material using the expansion anchor of the prior art example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Metal expansion anchor, 12 ... Expansion part, 13 ... Screw shaft part, 14 ... Anchor main body, 14a ... Core-rod accommodation hole, 14b ... Opening part, 14e, 14f ... Hole wall contact part, 14g ... Hole wall contact Part (protrusion), 14h ... hole wall contact part (sleeve), 15 ... core rod, 16 ... washer, 17 ... nut, 21 ... metal expansion anchor, 21A ... anchor body, 22 ... taper bolt, 221 ... expanded diameter part, 222 ... Screw shaft portion, 23 ... Expansion sleeve, 231 ... Expansion portion, 24 ... Hole wall contact portion (rigid sleeve), 25 ... Washer, 26 ... Spring washer, 27 ... Nut, 28 ... Driving rod, 31 ... Metal expansion Anchor, 32 ... bolt, 321 ... screw shaft part, 324 ... cone part, 326 ... hole wall contact part, 33 ... expansion part, 34 ... nut, 35 ... washer, 41 ... metal expansion anchor, 42 ... anchor body, 3 ... screw shaft, 44 ... rigid sleeve, 110 ... base material, 111 ... lower hole, 112 ... opening, 113 ... inner wall surface, 130 ... fittings, 131 ... through hole.

Claims (9)

An anchor body having an extended portion at the tip that is expanded in a pilot hole drilled in the base material;
Further, the pilot hole is provided on the outer periphery of the anchor main body at a position separated from the extended portion toward the rear end, and is in direct contact with the inner wall surface of the pilot hole having a larger diameter than the anchor main body. A metal expansion anchor having a hole wall contact portion housed therein.   The metal expansion anchor according to claim 1, wherein the hole wall contact portion is provided at a plurality of locations in the longitudinal direction of the anchor main body.   3. The metal expansion anchor according to claim 2, wherein at least one of the plurality of hole wall contact portions is formed by a protrusion protruding from a peripheral surface of the anchor main body.   The hole wall abutting portion is a rigid sleeve that is extrapolated to the rear end side of the extension portion of the anchor body and is accommodated in the lower hole in a state of being in direct contact with the inner wall surface of the lower hole. The metal expansion anchor according to claim 1 or 2.   Furthermore, a nut screwed into a screw shaft portion extending from the extension portion of the anchor body toward the rear end side, and a core rod insertion hole that is formed in the anchor body and opens at the rear end of the anchor body. The metal expansion anchor according to any one of claims 1 to 4, further comprising: a core rod that is housed in the expansion portion and expands the expansion portion by driving into the expansion portion. It is a sleeve driving type metal expansion anchor,
A taper bolt,
In the pilot hole that is extrapolated to the taper bolt and drilled in the base material, it is expanded by being driven from the rear end side of the taper bolt into the taper-shaped enlarged portion formed at the tip of the taper bolt. An expansion sleeve fixed to the material,
After the expansion sleeve is driven into the expanded diameter portion and expanded, the taper bolt is externally inserted from the rear end side and disposed on the rear end side of the expansion sleeve, and in a state of being in direct contact with the inner wall surface of the lower hole. A rigid sleeve housed in the pilot hole;
And a nut that is screwed into a portion of the threaded shaft portion on the rear end side of the taper bolt that protrudes from the opening of the lower hole after the rigid sleeve is received in the lower hole. Metal expansion anchor. It is a metal expansion anchor of a tightening method,
Bolts,
In a pilot hole that is extrapolated to this bolt and drilled in the base material, a sleeve-like shape that is expanded by pressing a tapered cone portion provided at the tip of the bolt and fixed to the base material An extension of
On the rear end side opposite to the front end side to be inserted into the lower hole of the bolt rather than the extension portion, the outer periphery of the bolt is provided integrally or separately with the bolt, and the inner wall surface of the lower hole A hole wall abutting portion housed in the lower hole in a state of being in direct contact with
A metal expansion anchor comprising: a screw shaft portion provided on a rear end side of the bolt; and a nut provided on a rear end side of the bolt with respect to the hole wall contact portion. . An anchor body having an extended portion that extends in the lower hole drilled in the base material is inserted into the lower hole formed in the base material, and the extended portion is expanded and fixed to the base material. After
A rigid sleeve received in the lower hole in direct contact with the inner wall surface of the lower hole formed to have a larger diameter than the anchor main body is extrapolated from the rear end side to the anchor main body and stored in the lower hole. The construction method of the metal expansion anchor characterized by the above-mentioned. It is a construction method of the metal expansion anchor according to claim 6,
Inserting the anchor body formed by extrapolating the expansion sleeve into the taper bolt into a prepared hole drilled in a base material, with the expanded diameter portion at the tip of the taper bolt in contact with the innermost part of the lower hole, After the expansion sleeve is driven into the expanded diameter portion by a driving rod from the rear end side of the taper bolt and expanded to fix the anchor body to the base material,
A rigid sleeve that is in direct contact with the inner wall surface of the lower hole that has a larger diameter than the anchor main body and is accommodated in the lower hole is extrapolated from the rear end side to the anchor main body and is accommodated in the lower hole. The construction method of the feature metal expansion anchor.

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