JPH0571517A - Anchor - Google Patents

Abstract

PURPOSE:To eliminate a loss in the time of assembly of a plug in a job site, and to prevent the plug from coming off from an anchor nut during transportation, by lightly fitting a locking part formed in the rear end part of the plug, in the anchor nut. CONSTITUTION:The radius of the rear end part of a plug 4 is formed smaller than the thread radius of a thread hole 1, and the outer peripheral surface of the rear end part of the plug is knurled so as to form a concave and convex surface 5, and the radius measured from the top ends of ridges on the surface to the axis of the plug is set to be slightly larger than the thread radius. Further, the plug 4 is inserted into an anchor nut, and the top end of the plug 4 is lightly tapped in order to push the plug 4 into an opening in the anchor nut 7 for holding the plug therein. The front end edge of the concave and convex surface 5 is made into press-contact with the top part of the thread hole 1, and there is no such a risk that the plug 4 comes off from the anchor nut 7. Further, upon use, the end face of the plug 4 is lightly tapped in order to enlarge a split part 9 of the anchor nut 7, and accordingly, the plug 4 is wedged into a concrete wall or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal anchor for fixing in a hole formed in a base material such as concrete or rock, and particularly, the plug is inserted from the opening side of the screw hole of the anchor nut. Which has a locking portion at the rear end of the plug.

[0002]

2. Description of the Related Art The above-mentioned anchors are shipped with the plugs incorporated in the anchor body at the time of shipment in order to prevent time loss when the plug is incorporated into the anchor body at the enforcement site and for reasons such as loss of the plug. .. However, even if the plug is simply installed in the anchor body, if the outer shape of the plug is smaller than the inner diameter of the screw hole of the anchor nut,
The plug may slip out of the anchor nut due to vibration during transportation. In order to prevent this, the one described in Japanese Utility Model Publication No. 56-7692 in which a collar is provided at the rear end of the plug,
An anchor plug described in Japanese Utility Model Publication No. 62-24808 has been proposed.

[0003]

This plug is composed of a short cylindrical main body having a tapered tip and a flange portion projecting from the rear end thereof. The plug is formed by casting or forging. I have no choice. However, according to the experiments conducted by the present inventor, when such a collar portion is manufactured by casting and forging, it is extremely difficult to accurately maintain the roundness of the collar portion. Also, in order to improve the accuracy of the plug, if it is attempted to manufacture it by cutting, the number of manufacturing processes will increase and it will become an expensive anchor. Since anchors are generally used in large quantities in various concrete works, it is necessary to mass-produce them at low cost. However, the conventional flanged plug cannot increase the roundness of the flange portion when it is manufactured inexpensively, and as a result, the thread may be damaged when the plug is inserted into the anchor nut. There is.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an anchor in which the above problems are eliminated, and the following constitution is adopted to achieve the object. That is, in the anchor of the present invention, the anchor nut 7 is formed in a tubular shape,
A screw hole 1 is formed on one end side thereof, and a split cylinder part 3 having a tapered hole 2 is integrally provided on the other end side thereof. Then, the plug 4 formed in a short cylindrical shape with a tapered tip is press-fitted into the anchor nut 7. Here, the feature of the present invention is that the radius of the rear end portion of the plug 4 is formed smaller than the radius of the screw thread of the screw hole 1, and the outer periphery of the smaller rear end portion is knurled in the axial direction. Uneven surface 5 having a large number of ridges (6) parallel to
Is formed, and the radius between the tip of the ridge 6 and the axis of the plug is slightly larger than the radius of the thread.

[0005]

Since the outer peripheral surface of the rear end portion of the cylindrical portion 9 shown in FIG. 4 is knurled to form the uneven surface 5 as shown in FIGS. Can be formed more accurately and easily than that of the conventional collar. Further, since the pitch and height of the uneven surface 5 are formed remarkably smaller than those of the screw hole 1 of the anchor nut 7, and the ridge 6 is formed slightly larger than the inner diameter of the screw hole 1, By pushing the plug 4 from the opening of the anchor nut 7, the plug 4 can be held in the anchor nut 7 without damaging the inner screw. Then, at the time of use, the split cylindrical portion 3 of the anchor nut 7 can be expanded by further striking the end surface of the plug 4, and the split cylindrical portion 3 can be bite to concrete or the like.

[0006]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a partial vertical cross-sectional view of the anchor of the present invention, showing a step before inserting the plug 4 into the anchor nut 7. 2 is a partially enlarged view thereof, and FIG. 3 is a partial view taken along the line III-III of FIG. Also, FIG. 4 and FIG.
Shows the manufacturing process of the plug 4 in order, FIG. 6 is a partial view of the upper end face of the plug 4, and FIG. 7 is a vertical sectional view showing a state in which the plug 4 is inserted into the anchor nut 7. In the combination of the anchor nut 7 and the plug 4 of FIG. 1, the anchor nut 7 is the same as the conventional one, and the feature of the present invention is the plug 4. And the cylindrical portion 9 of the plug 4
The uneven surface 5 formed at the rear end is characteristic.

First, the plug 4 having a cylindrical portion 9 and a tapered surface 8 as shown in FIG. 4 is manufactured. this is,
A tip end of a round bar having a radius r is cut into a predetermined length, and then a tapered surface 8 is formed by forging, and then knurling is performed at an appropriate position of the columnar portion 9. In this embodiment, the knurled concavo-convex surface 5 comprises a large number of grooves parallel to the axis of the cylindrical portion 9. The distance R between the tip of the ridge 6 of the concave-convex surface 5 and the axis is slightly larger than the inner radius R ₀ of the threaded hole 1 of the anchor nut 7 as shown in FIGS. 2 and 3. or,
The radius r of the cylindrical portion 9 of the plug 4 is smaller than the inner radius R ₀ of the screw hole 1 of the anchor nut 7. That is,
By forming the concavo-convex surface 5 around r ₁ as shown in FIG. 6, the tip of the ridge 6 projects beyond the radius r. Further, the concave portion of the uneven surface 5 is formed on the center side by the amount of the protrusion.
Therefore, it is _{R-r = r-r 1} . This r ₁ is the distance between the valley of the uneven surface 5 and the axis. Incidentally, R-r is about 0.1 to 0.2 mm in this embodiment. The pitch of the ridges of the knurl is about 0.3 mm to 0.7 mm.

An example of each dimension of the plug 4 at this time is as follows. First, the outer diameter of the cylindrical portion 9 is 8.3 mm, the outer diameter of the tip of the tapered surface 8 is 7 mm, and the overall length is about 15 mm. Furthermore, the total length of the anchor nut 7 is 40 mm, and the inner diameter of the screw hole 1 is 8.4 mm. This screw hole 1 has an outer diameter of 10
It is formed so that a bolt defined by JIS of mm can be screwed and fastened. Further, the split cylinder portion 3 having four slits is provided on the other end side of the anchor nut 7. A taper hole 2 is formed on the inner surface thereof. The plug 4 is inserted into the anchor nut 7 thus formed. Then, only the uneven surface 5 is projected from the nut. In addition,
The upper end of the screw hole 1 may be formed in a tapered shape, and in that case, the uneven surface 5 is inserted into the taper. Therefore,
When the upper end of the plug 4 is tapped with an appropriate tool, the tip end of the ridge 6 of the uneven surface 5 is elastically or slightly plastically deformed, and is inserted into the screw hole 1.

FIG. 7 shows this state. Then, the tip edge of the uneven surface 5 is pressed against the top of the screw hole 1, and the plug 4 does not come out of the anchor nut 7. That is,
There is no risk that the plug 4 will come out of the anchor nut 7 due to vibration during transportation. In addition, there is no fear that the plug 4 will drop in the work of driving the anchor upward on the ceiling surface. In this way, the anchor in which the plug 4 and the anchor nut 7 are combined is inserted into a concrete drilling hole (not shown), and the upper surface of the plug 4 is strongly tapped again with an appropriate tool. Then, the columnar portion 9 enters the split cylinder portion 3, expands the split cylinder portion 3, and the outer surface of the split cylinder portion 3 and the concrete hole are bitten.

[0010]

The anchor of the present invention is constructed as described above, and after the radius of the rear end portion of the plug 4 is formed to be smaller than the thread radius of the screw hole 1, the outer periphery of the rear end portion is reduced. An uneven surface 5 is formed by knurling on the
The radius of the tip of the plug and the axis of the plug is slightly larger than the radius of the screw thread. Therefore, the manufacturing of the plug 4 is extremely easy, and the manufacturing accuracy thereof, in particular, the circularity of the uneven surface 5, that is, the circularity formed by the outer edges of the convex stripes 6 of the uneven surface 5 can be accurately maintained. .. Therefore, the screw hole 1 is not damaged when the plug 4 is press-fitted into the anchor nut 7, and the bolt can be smoothly screwed into the screw hole 1 after the anchor is installed. Thereby, an anchor with good workability can be provided. Also, the uneven surface 5 of the plug 4
By press-fitting the screw into the screw hole 1 to some extent, it is possible to provide an anchor in which the plug 4 and the anchor nut 7 are integrated, and it is not necessary to combine the two in the field, and from that point as well. It becomes an anchor with good workability.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view of an anchor of the present invention, showing a pre-stage of inserting a plug 4 into an anchor nut 7.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a partial view taken along the line III-III in FIG.

FIG. 4 shows a first manufacturing process of the plug 4.

FIG. 5 shows a second manufacturing process of the plug 4.

FIG. 6 is a partial view of an upper end surface of a plug 4.

FIG. 7 is a vertical cross-sectional partial view showing a state where the plug 4 is inserted into the anchor nut 7.

FIG. 8 is a partial vertical cross-sectional view of a conventional anchor.

FIG. 9 is a front view of the plug 4 of another conventional anchor.

[Explanation of symbols]

 1 Screw Hole 2 Tapered Hole 3 Split Cylinder 4 Plug 5 Convex Surface 6 Convex Strip 7 Anchor Nut 8 Tapered Surface 9 Cylindrical 10 Collar

Claims (1)

[Claims] 1. An anchor nut in which a screw hole (1) is formed at one end side of a tubular shape, and a split cylinder part (3) having a tapered hole (2) at the other end side is integrally provided. (7),
An anchor having a plug (4) press-fitted into the anchor nut (7) and formed in a short cylindrical shape with a tapered tip, wherein a radius of a rear end portion of the plug (4) is the screw hole (1). After being formed smaller than the radius of the thread of
An uneven surface (5) having a large number of ridges (6) parallel to the axial direction formed by knurling is formed on the outer periphery of the small rear end portion, and the radius between the tip of the ridge (6) and the axis of the plug is An anchor characterized in that it is formed slightly larger than the radius of the thread.