JPH02168009A - Expansion anchor driving pin - Google Patents

Abstract

PURPOSE:To decrease inserting resistance, ensure a leg open portion to open extensively and secure drawing strength by having a recessed groove which is extended from a sharpened portion toward a shaft provided on the outer periphery of a driving pin and a protruded portion which is formed in the space of the recessed groove engage with a slit groove in an anchor structure. CONSTITUTION:A driving pin 11 has the tip portion provided with a conically sharpened portion 12 and the outer periphery provided with a protruded portion 14 in the space thereof to a recessed groove 13 which is extended from the sharpened portion 12 toward a shaft. This sharpened portion 14 is extended from the tip portion of an anchor structure 21 toward the shaft, provided in correspondance to a slit groove 25 which reaches the narrowed portion 24 of a pin hole 23 and formed so that a side wall face 15 is ended with the tip of a pin. It is thus possible to decrease inserting resistance against the anchor structure 21, extend a leg open portion easily and set drawing strength as a preset value.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a driving pin for use in a pin-driving type expansion anchor used for attaching and fixing various objects and equipment to concrete walls.

A conventional pin driving type amplification anchor, as shown in FIG. 6, for example, consists of a cylindrical anchor body 1 and a driving pin 2 inserted into a pin hole 3 of the anchor body 1. , an open leg part that can be expanded by having a narrowed part 4 at the innermost tip part of the pin hole 3 and provided with a plurality of split grooves 5 that extend in the axial direction from the tip surface and reach the narrowed part 4 of the pin hole 3. 6 is formed, and a tightening nut 8 is screwed into a threaded portion 7 provided on the outer periphery of the rear end. On the other hand, the driving pin 2 has a bullet-shaped sharp portion 9 at its tip and a head 10 at its rear end.

Problems to be Solved by the Invention In this type of expansion anchor, the opening leg portion 6 is moved by the tip portion 9 of the driving pin 2 inserted into the pin hole 3 of the anchor body 1 by the impact force in the axial direction. However, the insertion resistance of the driving pin 2 when expanding the leg part 6 is very large, and the leg part 6 cannot be expanded sufficiently, and the required handling strength (holding force) is ) was difficult to obtain.

Particularly, when the anchor body 1 has a large diameter, the opening of the legs 6 is insufficient.

In addition, in order to prevent the driving pin 2 inserted into the pin hole 3 of the anchor body 1 and assembled from falling off due to accidental handling during transportation, the driving pin 2 is attached to the anchor body 1 with adhesive.
However, this method of using pins with adhesive has the problem that the fixing means is troublesome and costly.

The present invention has been made in view of the above circumstances, and by changing the shape of the sharp portion of the driving pin, the insertion resistance is significantly reduced and the leg portion of the anchor body is easily and reliably expanded. It is an object of the present invention to provide a driving pin for an expansion anchor in which the pin itself has a later locking function.

Means for Solving the Problems In order to achieve the above object, the driving pin of the present invention is provided with a plurality of grooves extending in the axial direction from the sharp portion on the outer periphery thereof, and a plurality of grooves are formed between the grooves. It is characterized in that the protruding portion is configured to engage with the dividing groove.

It is effective to form the protruding portion gradually narrower toward the tip of the pin.

Further, it is preferable that the opening angle of the groove is about 100 degrees, and the thickness between the side wall surfaces of the protrusion gradually becomes thinner toward the outside in the radial direction.

Function When the driving pin having the above structure is inserted into the pin hole of the anchor body and a striking force is applied, the protrusion portion engaged with the split groove of the anchor body acts to spread the split groove, so that the protrusion The wedge action of the striations and the imitation action of the sharp end of the pin combine to easily and reliably expand the leg portion of the anchor body.

Moreover, since the protruding portion is press-fitted and engaged with the split groove of the anchor body, the driving pin is firmly held against the anchor body and will not fall off unexpectedly.

Example Embodiments of the present invention will be described below based on the drawings.

1 and 2 show the main parts of a driving pin according to the present invention, in which a conical sharp part 12 is provided at the tip of an elongated cylindrical pin body 11, and a head (not shown) is provided at the rear end. However, according to the present invention, the tip end portion of the pin is formed in the shape of a Phillips screwdriver bit. That is, a plurality of concave grooves 13 (four in the illustrated example) are provided on the outer periphery of the pin body 11 extending in the axial direction from the sharp portion 12, and a plurality of protrusions 14 (in the illustrated example) are provided between the concave grooves 13. 4) are formed. As shown in FIG. 3, each protrusion 14 has four split grooves 25 that extend in the axial direction from the distal end surface of the anchor body 21 and reach the narrowed portion 24 of the pin hole 23.
The phase is set to differ by 90 degrees to correspond to the
Further, both side wall surfaces 15.15 are formed to become narrower in width so as to converge toward the tip of the pin. Furthermore, as shown in FIG. 2, the side wall surfaces 15.15 are inclined so as to converge outward in the radial direction by forming the groove 13 into a V-shaped cross section with an opening angle α of about 100 degrees. However, the thickness between the side wall surfaces 15 and 15 gradually becomes thinner toward the radial direction outward.

When the driving pin configured as described above is inserted into the pin hole 23 of the anchor body 21 as shown in FIG.
At the inner narrowed part 24, each protrusion 14 is press-fitted into the corresponding split groove 25 and engaged, and both side wall surfaces 15.1
Opposing surfaces 26a, 26a of the open leg parts 26.26 where 5 is adjacent
It is held in place by pressing into contact with. By this locking and holding, the pin body 11 is reliably held on the anchor body 21, and accidental falling off is effectively prevented. In other words, the driving pin itself has a v;LG locking function.

Next, with the anchor body 21 inserted into a pilot hole (not shown) made in a concrete wall or the like, an impact force is applied to the pin body 1 in the axial direction and the pin body 2 is press-fitted into the anchor body 2, as shown in FIG. As shown in , the spread legs 26 are expanded. At this time, the protruding portion 14 engaged with the split groove 25 of the anchor body 21 acts to spread the split groove 25, and the sharp portion 12 pushes the open leg portion 26 apart via the narrowed portion 24. The both side wall surfaces 15°15 of the protrusion 14
The wedge action by the sharp portion 12 and the wedge action by the sharp portion 12 combine to reduce the insertion resistance of the pin body 11 and allow the leg portion 26 to be easily and reliably expanded.

FIG. 5 shows an example in which the present invention is applied to a female screw anchor in which a female screw hole 22 is provided in an anchor body 21. In this case, the only difference from the above embodiment is that the driving pin 11 is formed short and accommodated in the pin hole 23, and a cross groove 16 for engaging a driving tool is provided at the top of the driving pin 11. The operation and effect are the same as those of the previous embodiment.

The pin main body 11 and the anchor main body 21 described above are usually made of a metal material such as mild steel, but if heat insulation is required, they may be made of a plastic material with high tensile strength, such as polyamide resin and glass. It is also possible to manufacture it from a composite material mixed with fibers.

Effects of the Invention Since the present invention is configured as described above, the insertion resistance to the anchor body is significantly reduced, the legs of the anchor body can be easily and reliably expanded, and the predetermined length can be expanded. Strength (holding power) can be easily obtained.

Furthermore, since the driving pin itself has a locking function for handling the anchor body, there is no need for temporary locking means using adhesive as in the past, and the number of man-hours and costs can be reduced accordingly.

[Brief explanation of the drawing]

Fig. 1 is an enlarged front view of the main parts of the driving pin according to the present invention, Fig. 2 is a sectional view taken along line 2-2 in Fig. 1, and Fig. 3 is a vertical sectional front view showing the state in which it is assembled to the anchor body. , Fig. 4 is a front view of the main part showing the same usage state, Fig. 5 is a partially longitudinal front view showing another embodiment, and Fig. 6 is a partially longitudinal front view showing an example of the conventional expansion anchor. It is a diagram. 11...Pin body 12...Sharp part 13...
・Concave groove 14...Protrusion 15...Side wall surface 21 of protrusion 14...Anchor body 23...Pin hole 24...
・Narrowed part 25...Split groove 26...Open leg part 26a...Opposing surface of the open leg part 26 FIG.

Claims (3)

[Claims] (1) In addition to providing a narrowing part at the inner tip of the pin hole,
A cylindrical anchor body having a plurality of split grooves extending in the axial direction from the distal end surface and reaching the narrowed part to form a plurality of open leg parts, and a cylindrical anchor body that is inserted into the pin hole of the anchor body and has a sharp part at the tip. An expansion anchor consisting of a driving pin, wherein a plurality of grooves are provided on the outer periphery of the driving pin extending in the axial direction from the sharp portion, and a protrusion formed between the grooves is connected to the split groove. A driving pin for an expansion anchor, the driving pin being configured to engage with the expansion anchor. (2) The driving pin for an expansion anchor according to claim (1), wherein the protrusion portion is formed to become gradually narrower toward the tip of the pin. (3) Claim (1) characterized in that the opening angle of the groove is approximately 100 degrees, and the thickness between both side wall surfaces of the protrusion gradually becomes thinner toward the outside in the radial direction. Or (
2) Driving pin for the expansion anchor described.