JP2628005B2 - Construction method of concrete driving anchor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for installing a concrete driving anchor which is press-fitted into a pilot hole provided in a concrete frame and fixed.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 21217/1990 discloses a plurality of driving shafts connected to the end of a screw shaft, and a plurality of shafts each having a mountain-shaped cross section formed on the outer peripheral surface of the driving shaft. A method is described in which an anchor bolt is provided, which has a ridge and is provided with a tapered pilot portion at a tip portion, and the driving shaft portion of the anchor bolt is driven into a pilot hole provided in a concrete body to press-fit and fix the anchor bolt. ing.

[0003]

However, in the above-mentioned conventional method of installing an anchor bolt, since the driving shaft is directly driven into the opening of the pilot hole, the press-fitting resistance is large, and the anchor bolt is inclined and escaped. It occurred and was difficult to press fit.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and does not tilt or escape into the anchor body at the time of driving. It is an object of the present invention to provide a method of constructing a concrete driving anchor capable of obtaining force.

[0005]

In order to achieve the above object, a construction method according to the present invention is characterized in that a driving anchor is provided on the other end of an anchor body having a coupling means such as a male thread or a female thread at one end. A driving shaft portion having a diameter d smaller than the diameter D of the anchor body is continuously provided, and the driving shaft portion has an outer peripheral surface having a chevron-shaped cross section and an outer diameter substantially equal to the diameter D of the anchor body. A plurality of protrusions extending in the axial direction are provided, and a tip portion having a diameter d and a tapered pilot portion is formed. A first pilot hole having a diameter slightly larger than the diameter D of the first pilot hole;
Into a two-stage hole consisting of a second pilot hole that is continuous with the pilot hole and has a hole diameter slightly larger than the diameter d of the pilot portion,
In a state where the pilot portion of the driving anchor is inserted into the second pilot hole and guided for positioning, the driving shaft portion is driven into the second pilot hole while being guided along the first pilot hole, The ridge is press-fitted into the wall surface of the second pilot hole and fixed.

[0006]

According to the above construction, when the driving anchor is inserted into the pilot hole and the anchor body is driven with a hammer or the like while the pilot portion of the driving shaft is positioned and guided in the second pilot hole, the projecting ridge is formed. Is pressed into the wall surface of the second pilot hole so as to bite it, and is firmly fixed to the concrete skeleton. At this time, if a plurality of retaining projections are provided on the top of the ridge, a greater pull-out strength (holding force) can be obtained.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a concrete driving anchor according to the present invention, and FIGS. 2 and 3 show details of a driving shaft which forms the main part.

The driving anchor 1 is a single body formed by processing a metal wire rod by cold forging, and has a male screw part 3 and a frusto-conical head part 4 for driving at one end of a cylindrical anchor body 2. A driving shaft portion 5 having a diameter d smaller than the diameter D of the anchor main body 2 is provided continuously at the other end portion. A plurality of ridges 6 extending in the axial direction are protruded from the outer peripheral surface of the driving shaft portion 5, and a tapered pilot portion 7 having a diameter d is provided at a tip portion. The outer diameter of the ridge 6 is substantially the same as the diameter D of the anchor body 2. As shown in FIGS. 2 and 3, the ridge 6 is preferably a spiral ridge or an inclined ridge having a mountain-shaped cross-section and inclined at about 15 degrees with respect to the axis, but is preferably substantially parallel to the axis. It may be a ridge extending in the axial direction. The tip of each ridge 6 is formed in a tapered shape converging on the pilot portion 7 in order to reduce the press-in resistance at the time of driving. A large number of retaining projections 8 are provided on the top of each ridge 6. As shown in FIG. 4, the projection 8 is formed in a saw blade shape by an inclined surface 8a inclined at about 45 degrees with respect to the axis and a horizontal surface 8b extending in a direction perpendicular to the axis.
The penetration resistance is reduced by the inclined surface 8a in the driving direction of the driving shaft portion 5, and the horizontal surface 8b in the drawing direction.
The shape is such that a large resistance can be obtained.

The driving anchor having the above-mentioned structure is entirely subjected to a surface hardening treatment by a heat treatment or a surface coating treatment, so that not only the driving shaft portion 5 but also the male screw portion 3 for connection is increased in strength. .

Further, as shown by a virtual line in FIG. 1, it is possible to protrude a flange portion 9 on the outer peripheral surface of the anchor body 2. When such a flange 9 is provided, not only is it easy to automatically form the thread of the male screw portion 3 and the ridge 6 of the driving shaft portion 5 when it is rolled, but also, the driving amount of the driving anchor 1 can be reduced. 9 can be regulated, which is convenient in use and handling. In addition, it is more effective if the detents 10 project from the lower surface of the flange 9.

On the other hand, as shown in FIG. 5, a prepared pilot hole 12 provided in the concrete frame 11 has a first pilot hole 12a having a hole diameter slightly larger than the diameter D of the anchor body 2.
And a second pilot hole 12b which is continuous with the bottom of the first pilot hole 12a and has a hole diameter slightly larger than the diameter d of the pilot portion 7 of the driving shaft portion 5. The pilot hole 12 of such a two-step hole is used for the concrete 2 as shown in the figure.
It can be easily processed in one step using the step drill 13.

As shown in FIG. 6, the driving anchor 1 is inserted into the prepared hole 12 of the two-step hole, and the pilot portion 7 of the driving shaft 5 is positioned and guided in the second prepared hole 12b. When the head 4 of the anchor main body 2 is driven by using a hammer or the like, the driving shaft 5 is guided by the first pilot hole 12a, and does not generate inclination or escape.
While maintaining the coaxial attitude with respect to the pilot hole 12a, the protrusion 6 is press-fitted into the wall surface of the second pilot hole 12b,
As shown in FIG. 7, it is firmly fixed to the concrete skeleton 11. At this time, since the ridge 6 is spiral,
The rod 1 enters the inside of the pilot hole 12b while rotating slightly, and the pull-out resistance in the axial direction increases, and the pull-out resistance also increases due to the horizontal surface 8b of the retaining projection 8, so that the driving anchor 1 has a large pull-out strength as a whole. It is fixed to the concrete skeleton 11 with (holding force).

FIG. 8 shows an example in which a female thread 15 is provided on the anchor body 2 as a connecting means provided on the driving anchor 1. Also in this case, the outer peripheral surface of the anchor body 2 has a flange 9
Is preferably provided. Further, the connecting means provided on the driving anchor 1 is not limited to the male screw part 3 and the female screw part 15 shown in the above embodiment, and a hook or other mounting hardware can be provided.

[0014]

As described above, according to the construction method of the present invention, a two-stage hole of a first pilot hole and a second pilot hole is machined in a concrete body, and the hole is formed at the tip of the driving shaft of the anchor body. The driving shaft is driven while guiding the driving shaft along the first prepared hole in a state where the provided pilot portion is inserted into the second prepared hole and guided for positioning, so that the driving shaft is inclined or escaped. The protrusions provided on the outer peripheral surface of the driving shaft portion are firmly and reliably press-fitted so as to bite into the wall surface of the second pilot hole, and a large pull-out strength (holding force) is generated. can get.

[Brief description of the drawings]

FIG. 1 is a front view of a concrete driving anchor according to the present invention.

FIG. 2 is an enlarged front view of a driving shaft portion which is the main portion.

FIG. 3 is an enlarged end view of a driving shaft portion, which is the main portion.

FIG. 4 is an enlarged sectional view of a main part of the ridge.

FIG. 5 is a cross-sectional view showing a prepared state of a prepared hole provided in a concrete skeleton.

FIG. 6 is a sectional view of a main part showing a driving preparation state of the driving anchor inserted into the pilot hole.

FIG. 7 is a cross-sectional view of a main part showing the driving completed state.

FIG. 8 is a front view showing a driving anchor according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Driving anchor 2 Anchor main body 3 Male screw part 4 Head 5 Driving head 6 Ridge 7 Pilot part 8 Retaining projection 9 Flange part 11 Concrete frame 12 Preparatory hole 12a First prepared hole 12b Second prepared hole 15 Female screw part

Claims (4)

(57) [Claims] The driving anchor has a diameter d smaller than a diameter D of the anchor body at the other end of the anchor body having a coupling means such as a male thread or a female thread at one end.
A driving shaft portion is continuously provided, and the driving shaft portion is cut on the outer peripheral surface.
The surface shape is chevron, and the outer diameter is approximately the same as the diameter D of the anchor body.
A plurality of ridges having the same diameter and extending in the axial direction are provided.
With a diameter d at the tip and a taper
While the pilot is formed, the pilot hole drilled in the concrete body is
A first pilot hole having a diameter slightly larger than the diameter D;
1 pilot hole and slightly larger than the pilot section diameter d
Machining into a two-stage hole consisting of a second pilot hole with a critical hole diameter
And the pilot portion of the driving anchor is connected to the second
With the positioning guide inserted into the pilot hole,
The second shaft while guiding the shaft portion along the first pilot hole.
2 into the lower hole, and insert the ridge into the wall surface of the second lower hole.
For concrete, characterized by being pressed into
Construction method of embedded anchor. 2. A plurality of retaining projections are provided at the top of the ridge.
2. The concrete driving according to claim 1, which is provided.
Anchor construction method. 3. A collar portion is connected to said anchor body.
The concrete anchoring anchor according to claim 1 or 2,
Car construction method. 4. A collar is provided continuously with said anchor body.
And a detent is provided on the lower surface of the flange.
The concrete driving according to claim 1, 2 or 3, wherein
Construction method of only anchor.