JP3796387B2 - Method for forming post-installation anchor mounting hole and pilot hole diameter expanding tool - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a method of forming a hole for attaching a post-construction anchor, and in particular, forming a mounting hole that increases the pull-out resistance of the post-construction anchor by expanding the diameter of a prepared hole drilled in a base material such as concrete, stone, or rock. And a device for expanding the pilot hole.
[0002]
[Prior art]
Conventionally, in order to increase the pulling resistance of an adhesive anchor, it has been known to cut a plurality of expanded portions on a wall surface of a pilot hole with a uniform diameter drilled in a base material such as concrete, stone, or rock.
[0003]
In addition, as a pilot hole expanding tool for cutting the plurality of expanded portions, Japanese Patent Publication No. 2-33323 discloses that a cutter 30 is formed at the tip of the shaft 50 as shown in FIG. 51, and the shaft 50 is attached to the flange 51 so as to be movable in the axial direction, and Japanese Patent Laid-Open No. 52-86902 discloses the tip peripheral surface of the shaft 50 as shown in FIG. A cutter having a cutter 31 formed on one side and an increased weight on the cutter 31 side is disclosed.
[0004]
In the former case, the shaft 50 is inserted into the pilot hole 40 having a uniform diameter, the shaft 50 is turned while being supported by the stopper 52 via the flange 51, and the wall surface 41 is cut by the cutter 30 applied to the wall surface 41. Then, the first diameter-expanded portion 42a is cut, and then the shaft 50 is set up vertically, the shaft 50 is moved up and down while passing through the flange 51, and the above operation by the cutter 30 is performed again to perform the second expansion. The diameter portion 42b is cut, and the above steps are repeated to cut the desired number of diameter-expanded portions 42a, 42b, 42c.
[0005]
In the latter case, the shaft 50 is inserted into the pilot hole 40 having a uniform diameter, the cutter 50 is bent outward by centrifugal force by rotating the shaft 50, and the wall surface 41 is cut by the bent cutter 31. It is disclosed that the first diameter-expanded portion 42a is cut. From this, in order to cut a plurality of diameter-expanded portions, the shaft 50 is turned after the first diameter-expanded portion 42a is cut. The shaft 50 is stopped, the shaft 50 is moved in the vertical direction, the operation by the cutter 31 is performed again to cut the second enlarged diameter portion 42b, and the above steps are repeated to obtain a desired number of enlarged diameter portions 42a, 42b,.・ It is inferred that Note that the terms in the conventional examples and the expressions on the drawings are substantially the same, although they are partially different from the expressions in the publication for the convenience of the description of the present specification.
[0006]
In this way, in order to form the mounting hole for the post-construction anchor using the pilot hole diameter increasing tool in both conventional examples, the cutter is moved to the corresponding position each time a plurality of diameter enlarged parts are respectively cut. It must be repeated and the diameter cannot be expanded easily and quickly.
[0007]
[Problems to be solved by the invention]
It is an object of the present invention to form a mounting hole having a large pulling resistance easily and quickly by simultaneously cutting a plurality of enlarged diameter portions in a pilot hole.
[0008]
[Means for Solving the Problems]
In the present invention, the invention according to claim 1 is provided with a base-hole expanding tool having a plurality of pin-shaped cutters that are normally immersed in a cylinder and spaced apart in the axial direction of the cylinder. The plurality of pin-shaped cutters are simultaneously rotated around the center of the cylindrical body and protruded radially from the cylindrical body and moved forward so that the pilot holes are inserted into the prepared uniform-diameter prepared holes. A wall surface is cut and a plurality of enlarged diameter portions are simultaneously cut on the wall surface.
[0009]
According to the above means, since the pin-shaped cutter is always submerged in the cylinder, the cylinder is smoothly and easily inserted into the pilot hole, and then the plurality of pin-shaped cutters project simultaneously to cut the wall surface. Therefore, a plurality of enlarged diameter portions are simultaneously cut on the wall surface of the prepared hole by a single cutting operation.
[0010]
In the invention of claim 2, a cylindrical body is extrapolated on the shaft so as to be movable in the axial direction, a plurality of through holes are provided at intervals in the axial direction of the cylindrical body, and a plurality of diameters gradually increase toward the tip. The taper portion is continuously provided, the pin-shaped cutter that slides in and out of each through-hole by sliding on each taper portion is normally urged in the sinking direction by the first elastic body, and the rod is attached to the cylindrical body. A second elastic body that connects and urges the shaft in the protruding direction is interposed between the rod and the shaft.
[0011]
According to this means, since the pin-shaped cutter is always biased by the first elastic body in the sunk direction, the pin-shaped cutter is surely sunk and the cylindrical body can be easily and quickly and reliably placed in the pilot hole. If the cylindrical body is inserted into the pilot hole, the cylindrical body is rotated through the rod while the shaft is applied to the bottom of the pilot hole, and the cylindrical body is advanced Each pin-shaped cutter simultaneously rotates around the center of the cylindrical body and gradually advances along each tapered portion while projecting from the through hole against the first elastic body to cut the wall surface. A plurality of enlarged diameter portions are cut. The second elastic body contracts as the rod advances.
[0012]
Even after starting to pull out the cylindrical body through the rod after the diameter-enlarged portion has been cut, the shaft maintains the support state by the elastic pressure of the second elastic body, and if the cylindrical body is further pulled out, the first elasticity Each pin-shaped cutter is gradually retreated while being pressed by each taper portion due to the elastic pressure of the body and then submerged in the cylinder, and after that, if the cylinder is pulled out from the mounting hole, the shaft is integrated with the cylinder from the mounting hole. Extracted.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The pilot hole expanding tool 1 according to the present invention will be described. A plurality of, for example, four through holes 20 are arranged in the radial direction from the center hole 21 of the cylindrical body 2 made of a metal cylinder as shown in FIG. Further, a plurality of sets of the plurality of equally arranged through holes 20, 20... Are provided at a constant interval L in the axial direction of the cylindrical body 2 as shown in FIG. Specifically, four sets of four through holes 20, 20, 20, 20 are provided with a constant interval L. As shown in FIG. 2, a threaded ring 20 ″ is screwed into the threaded portion 20 ′ so as to be screwed at the open end of each through hole 20, thereby forming each through hole 20 into a stepped hole. 1, the front surface of the cylindrical body 2 is formed as a conical surface 22, and a screw hole 23 communicating with the central hole 21 and having a diameter larger than that of the central hole 21 is screwed to the rear end of the cylindrical body 2. As shown in Fig. 3 and 5, a plurality of spiral grooves 24, 24 ··· are recessed on the surface of the body 2. In this embodiment, four spiral grooves 24, 24 ··· are provided. It is intended to be recessed.
[0014]
The tip of the shaft 5 made of a metal round bar is conically formed to form a sharp portion 53, and a plurality of, for example, five taper portions 5a, 5a,... To be installed.
[0015]
As shown in FIG. 2, a pin that is inserted into the large-diameter portion 20 a of the stepped through-hole 20 and that has a bottom portion that is in contact with the tapered portion 5 a and a tip portion that is conical and that forms a cutter portion 33. The portion 34 is integrally formed or integrated by means such as fixing to form a metal pin-shaped cutter 3, and the pin portion 34 is formed so as to be fitted into the small diameter portion 20 b of the through hole 20, that is, the hole of the ring 20 ″. The coil spring 60 is wound around the pin portion 34 of each pin-shaped cutter 3 as the first elastic body 6.
[0016]
A male screw 71 is screwed on the outer periphery of the tip of the metal rod 7 (shown in FIG. 1), and a receiving hole 72 is formed from the tip surface. A coil spring 80 is inserted into the receiving hole 72 as the second elastic body 8.
[0017]
Then, the shaft 5 is inserted into the center hole 21 of the cylindrical body 2, and the pin-shaped cutter 3 around which the coil spring 60 as the first elastic body 6 is wound is inserted into each through hole 20. A ring 20 ″ is screwed into the screw portion 20 ′, and is normally urged by the spring pressure of the coil spring 60, which is the first elastic body 6, so that each pin-shaped cutter 3 is immersed in the cylindrical body 2. The bottom of the portion 32 is pressed against the smallest diameter portion of each taper portion 5a, and the side surface of the base portion 32 is locked to the step portion 5b with the subsequent taper portion 5a or the step portion 5b 'with the rear end portion 5a'. The male screw 71 of the rod 7 is screwed into the screw hole 23 and connected, and the coil spring 80, which is the second elastic body 8, is brought into contact with the rear end of the shaft 5. An insertion groove 20c is formed in the ring 20 ″. And inserts the tip of the screwdriver into the insertion groove 20c to perform the screw operation work. That.
[0018]
As described above, it is preferable that a plurality of stepped through holes 20, 20... Are arranged in the radial direction from the center hole 21 of the cylindrical body 2, and the pin-shaped cutter 3 is inserted into each through hole 20. In this case, the cutting efficiency is better than providing a single pin-shaped cutter in the radial direction from the center hole 21, and it is preferable to screw a ring 20 ″ into the open end of each through-hole 20. The pin-shaped cutter 3 worn by attaching and detaching the ring 20 ″ can be easily replaced, and it is preferable to form a sharp portion 53 at the tip of the shaft 5, and in this way, the pilot hole diameter increasing tool When 1 is inserted into the pilot hole 1, the stationary state of the shaft 5 can be reliably maintained as will be described later. Further, as described above, the spiral groove 24 is preferably provided on the surface of the cylindrical body 2, and in this way, chips generated by cutting can be sent outward as described later. Rotates smoothly without hindrance. By making the spiral groove 24 into a plurality of strips, the above effect can be achieved more efficiently.
[0019]
Next, a method for forming the post-installation anchor mounting hole in the present invention will be described. First, a hammer drill, a vibration drill, a tire mond, etc. are applied to various base materials 4 to which the post-construction anchor is to be fixed, such as stone, concrete, block, bedrock. A pilot hole 40 having a uniform diameter is drilled with a commonly used drilling machine tool (not shown) such as a core drill or a rock breaker (shown in the uppermost part of FIG. 5). Next, the rod 7 is connected to a rotary tool (not shown), and the pilot hole expanding tool 1 is inserted into the pilot hole 40 as shown in the second stage of FIG. Press. Here, the sharpened portion 53 is stuck to the hole bottom 44, and the stationary state of the shaft 5 is reliably maintained. At this time, as shown by the solid line in FIG. 1, each pin-shaped cutter 3 is urged in the sunk direction by the coil spring 60 which is the first elastic body 6 at the position of the minimum diameter portion of each tapered portion 5a. I am immersed in the body 2. After that, the rod 7 and the cylindrical body 20 integrated with the rod 7 are rotated and pushed by a rotating tool, and the cylindrical body is rotated while simultaneously rotating all the pin-shaped cutters 3, 3, 3 around the center 0 of the cylindrical body 2. 2 is gradually projected, and the wall surface 41 of the prepared hole 40 is simultaneously cut by all the pin-shaped cutters 3, 3, 3,. When the cylinder 2 is pushed in, as shown in FIGS. 1 and 2, all the pin-shaped cutters 3, 3, 3,... Slide the taper portions 5a of the stationary shaft 5 toward the maximum diameter portion. Thus, the coil spring 60 as the first elastic body 6 is contracted and protrudes from each through hole 20. In this way, the wall surface 41 of the pilot hole 40 is simultaneously cut by all the pin-shaped cutters 3, 3, 3..., And a plurality of enlarged diameter portions 42, 42, 42. At the same time, the mounting holes are formed. Further, the chips entering the spiral grooves 24, 24,... By the cutting are sent outward by the rotation of the cylindrical body 2 in the direction of the arrow in FIG. 5, and the rotation of the cylindrical body 2 is obstructed by the chips. There is no, and the cylinder 2 rotates smoothly. Note that the coil spring 80 as the second elastic body 8 contracts when the rod 7 is pushed.
[0020]
After the cutting of the enlarged diameter portions 42, 42, 42,..., The rod 7 and the cylindrical body 2 integrated with the rod 7 are pulled out from the mounting hole. At this time, the shaft 5 receives the spring pressure of the coil spring 80 which is the second elastic body 8 and keeps the stationary state, and each pin-shaped cutter 3 is the first elastic body 6 by pulling out the cylindrical body 2. While being pressed against each taper portion 5a by the spring pressure of a certain coil spring 60, the taper portion 5a slides toward the minimum diameter portion and dies in the cylindrical body 2. Further, when the cylindrical body 2 is pulled out together with the rod 7, the side surface of the base portion 32 of each pin-shaped cutter 3 is locked to the step portions 5b and 5b ', so that the shaft 5 is also pulled out integrally. Thereafter, the inside of the mounting hole a shown in the third stage of FIG. 5 is cleaned by a cleaner (not shown) such as a brush, blower, dust collector, etc., and the chips in the hole are completely removed.
[0021]
A method of attaching a post-construction anchor in the mounting hole a in which the expanded diameter portion has been cut is known. For example, as shown in the fourth stage of FIG. 5, a capsule containing an adhesive in the mounting hole a After inserting b, rotating and hitting the construction anchor c such as bolts and reinforcing bars, the capsule b is broken, and as shown in the lowermost part of FIG. 5, all the enlarged diameter portions 42, 42, 42. The mounting holes a are filled, the adhesive is cured, and the construction anchor c is fixed to the base material 4. Compared with the case where the adhesive anchor is fixed to the uniform-diameter mounting hole, a plurality of enlarged diameter portions 42, 42, 42,... The pulling resistance is much higher.
[0022]
【The invention's effect】
According to the present invention, it is not necessary to repeatedly cut each enlarged diameter portion, and a mounting hole having a plurality of enlarged diameter portions and having a large pulling resistance can be easily and quickly formed by a single cutting operation.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a use state of a pilot hole diameter increasing tool of the present invention.
FIG. 2 is a partial enlarged cross-sectional view showing the main part of the above.
FIG. 3 is a plan view in which a part of the above is cut away.
FIG. 4 is a cross-sectional view taken along line AA.
FIG. 5 is an explanatory diagram showing a method of the present invention.
FIG. 6 is a cross-sectional view of a conventional example.
FIG. 7 is a cross-sectional view of another conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pilot hole diameter increasing tool 2 Cylindrical body 3 Pin-shaped cutter 4 Base material 5 Shaft 5a Tapered part 6 1st elastic body 7 Rod 8 2nd elastic body 20 Through-hole 40 Pilot hole 41 Wall surface 42 Expanding part

Claims (2)

Insert a pilot hole expansion tool that has a plurality of pin-shaped cutters that are always immersed in the cylinder and spaced in the axial direction of the cylinder into a pilot hole of uniform diameter drilled in the base material. The plurality of pin-shaped cutters are simultaneously rotated around the center of the cylindrical body, protruded radially from the cylindrical body and advanced to cut the wall surface of the pilot hole, and a plurality of A method of forming a mounting hole for a post-construction anchor, wherein the enlarged diameter portion is simultaneously cut. A cylindrical body is extrapolated to the shaft so that it can move in the axial direction, a plurality of through holes are provided at intervals in the axial direction of the cylindrical body, and a plurality of taper portions that gradually increase in diameter toward the tip are connected to the shaft. And a pin-shaped cutter that slides on each tapered portion and protrudes and retracts from each through hole is normally urged by the first elastic body in the sinking direction, and a rod is connected to the cylindrical body, A pilot hole diameter increasing tool, wherein a second elastic body for biasing the shaft in the protruding direction is interposed between the shaft and the shaft.

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