JP2002356848A - Anchor pull-out instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anchor pull-out instrument which can easily and safely remove a post-driven anchor fixed in concrete. SOLUTION: The anchor pull-out instrument 11 functions to pull an anchor 7 formed of a main body portion 20 and a cone 21, out of the concrete 25. The main body portion 20 of the anchor is comprised of an expandable portion 19 which is cylindrically formed, and has a female screw portion 18 formed in an inner peripheral surface thereof and a slit 23 formed in a bottom portion thereof, whereby the expandable portion 19 is expandable. The cone 21 is inserted into the expandable portion 19. The anchor pull-out instrument 11 is formed of a polygonal head portion 12 which is rotatable by a wrench or the like, and a neck portion 13 extending from the head portion 12. The neck portion 13 has a male screw portion 14 at a base-side end thereof, for being screwed into the female screw portion 18. Further, the neck portion 13 has a truncated-conical or tapered shaft portion 15 at a proximal end thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor removal tool for removing a post-punched anchor which is inserted into concrete and fixed.

[0002]

2. Description of the Related Art Conventionally, for example, in the case of renovation work or temporary facility work, when a post-installed anchor that is inserted into a concrete structure and fixed is to be removed after the work is completed, a tool such as a sander is used. They are used to scrape off the anchors, or use crowbars to break the concrete and remove the anchors.

[0003]

In the conventional operation of removing an anchor, there is a problem in safety management because dust is scattered around when an anchor is scraped or concrete is hung. Furthermore, these operations not only generate vibrations and noises but disturb the surroundings, and also have a problem that the scraped concrete pieces and the like become industrial waste.

Accordingly, in the conventional operation of removing the anchor, it is necessary to avoid the problem of safety management due to the scattering of dust to the surroundings, to prevent the generation of vibration and noise, and to reduce unnecessary industrial waste. There is a problem that must be solved so that it does not occur.

[0005]

As a specific means for solving the problems of the prior art, the present invention is directed to a cylindrical type having a female screw portion formed on the inner peripheral surface and a slit provided on the bottom side so as to be expandable. An anchor puller for pulling out an anchor provided with a main body having a widened portion and a cone inserted into the expanded portion from concrete, wherein the anchor puller is formed in a polygonal shape using a wrench or the like. The head comprises a rotatable head and a neck connected to the head, and a male thread is formed at the base of the neck to be screwed with the female thread, and at the end of the neck. It is an object of the present invention to provide an anchor removal tool characterized in that a frustoconical or tapered shaft is provided.

The dimension of the shaft portion is longer than the dimension from the end of the internal thread portion to the upper end of the cone in the extension portion and shorter than the dimension of the extension portion. The size of the neck is longer than the sum of the size of the female thread and the dimension from the end of the female thread to the upper end of the cone in the extension.

In the anchor puller according to the present invention,
By screwing the male screw part into the female screw part of the anchor and making the tip of the shaft contact the upper end of the cone, further forcibly rotating the head and screwing the male screw part into the female screw part Since the anchor protrudes in the direction opposite to the screwing direction, that is, in the outward direction of the concrete, the anchor fixed in the concrete can be removed very easily. Further, unlike the conventional example, since no power tool or the like is used, it is safe, does not require a power source, and does not generate industrial waste such as concrete pieces. The anchor puller is a small part, easy to carry, and does not require a large space for storage.

[0008]

Next, embodiments of the present invention will be described with reference to the drawings. First, in FIG.
Reference numeral 11 denotes an anchor pull-out tool. The anchor pull-out tool 11 is formed in a bolt shape, and includes a head 12 and a neck 13 connected to the head 12.

The head 12 is formed, for example, in a hexagonal or quadrangular shape, and the anchor puller 11 can be screwed in by rotating the head 12 using a tool such as a wrench.

The neck portion 13 is formed with an external thread by cutting an external thread on the outer peripheral surface on the base side, and the external thread portion 14 can be screwed with the internal thread portion 18 of the anchor 17. The dimension of the male screw part 14 is about 36 mm as an example.
It is about. Note that the symbol d in FIG. 1 is a dimension for about three pitches of the male screw portion 14, and the d dimension is about 7 mm as an example. The size of the reference f is about 36 m.
The value obtained by subtracting the above-mentioned about 7 mm from m is about 29 mm.

A shaft 15 is provided at the end of the neck 13. The shaft portion 15 is formed in a truncated cone shape with a tapered portion 16 provided on the outer peripheral surface. The shape of the shaft portion 15 is not necessarily limited to the truncated cone shape, and may be formed in a tapered shape so as to be shorter than the diameter of the male screw portion 14. That is, the male screw portion 14 is screwed into the female screw portion 18, and the tip 15 a of the shaft portion 15 is connected to the upper end 2 of the cone 21.
What is necessary is that there is a gap between the shaft portion 15 and the inner peripheral surface of the expansion portion 19 when the shaft portion 15 is brought into contact with the shaft 1a. The dimension c of the shaft 15 is, for example, about 22 mm.

Next, a post-stroke anchor 17 that is pulled out using the anchor pull-out tool 11 will be described. As shown in FIG. 2, the anchor 17 has a main body 20 having a female threaded portion 18 formed on the inner peripheral surface thereof and having an extended portion 19 on the bottom side, and a cone 21 inserted into the extended portion 19. Consists of

The female screw portion 18 is formed by cutting a female screw on the inner peripheral surface of the main body portion 20, and the dimension e of the female screw portion 18 is about 29 mm as an example.

The extension portion 19 has a slit 23 formed on the bottom side and is provided so as to be able to expand outward. Incidentally, the dimension b of the extension 19 is about 25 mm as an example.

The cone 21 is formed in a truncated cone shape with a tapered surface 24 formed on the outer peripheral surface. In addition, cone 2
The dimension of 1 is, for example, about 25 mm. Further, from the end portion 18a of the female screw portion 18 to the upper end portion 21a of the cone 21
The dimension a up to about 18 mm is, for example, about 18 mm.

When the anchor 17 having such a structure is inserted into the concrete 25, the expansion portion 19 expands outward due to the presence of the cone 21, and the anchor 17 enters the hole wall of the concrete 25 and is fixed (FIG. 3). reference).

Next, c of the shaft portion 15 of the anchor removal tool 11
The dimensions and the like will be described in detail. In order to reliably pull out the anchor 17 from the concrete 25, it is necessary to form the c-dimension and the like of the shaft portion 15 in an optimum size corresponding to the size (each dimension) of the anchor 17. In other words, the dimension c of the shaft portion 15 is the same as that of the end portion 18 a
The length (f + d + c) of the neck 13 is set to be longer than the dimension a from the to the upper end 21a of the cone 21 and shorter than the dimension b of the expanded portion 19. It is desirable that the length be longer than the sum of the dimension and the dimension a from the end 18 a of the female screw portion 18 to the upper end 21 a of the cone 21 in the extension 19. An equation for determining the c dimension and the like of the shaft portion 15 is shown as follows.

"A <c <b" and "(f + d + c)>
(E + a) "c = dimension of the shaft portion 15 a = dimension from the end 18a of the female screw portion 18 in the extension portion 19 to the upper end portion 21a of the cone 21 b = dimension of the extension portion 19 f + d + c = dimension of the neck portion e = Dimension of female thread 18

Thus, the dimension c of the shaft 15 and the neck 13
By determining the (f + d + c) dimensions of
4 can be screwed into the female screw portion 18 so that the tip 15a of the shaft portion 15 can be reliably brought into contact with the upper end portion 21a of the cone 21. In this state, the head 12 of the anchor puller 11 is removed.
Are located at a required interval from the anchor 17. Therefore, since the head 12 of the anchor removal tool 11 is securely rotated and screwed in, the anchor 17 can be protruded in the direction opposite to the screwing direction.

Next, a method of using the anchor puller 11 will be described. First, the male screw portion 1 of the anchor puller 11
4 is screwed into the female thread 18 of the anchor 17 to
Then, the head 12 is forcibly rotated to screw the male screw portion 14 into the female screw portion 18 (in the direction of arrow A in FIG. 3). The rotation of the male screw portion 14 causes the anchor 17 to protrude in the direction opposite to the screwing direction (the direction of arrow B in FIG. 3), that is, in the outward direction of the concrete 25. At this point, since the frictional force between the outer peripheral surface of the expansion portion 19 and the hole wall is cut off, the anchor 17 may be pulled out. In this way, the anchor 17 fixed in the concrete 25 can be removed very easily.

[0021]

As described above, the anchor puller according to the present invention is a tubular body having a female screw portion formed on the inner peripheral surface and a slit provided on the bottom side and having an expandable expansion portion. An anchor puller for pulling out an anchor provided with a portion and a cone inserted into the expansion portion from concrete, wherein the anchor puller is formed in a polygonal shape and is rotatable with a wrench or the like. A neck portion connected to the head portion, a male thread portion to be screwed with the female thread portion is formed on a base side of the neck portion, and a truncated cone or tapered shape is formed on an end side of the neck portion. The shaft part is provided, so that the male screw part of the anchor removal tool is screwed into the female screw part of the anchor, and the tip of the shaft part is brought into contact with the upper end of the cone, further forcibly rotating the head Screwing the male thread into the female thread The car and screwing direction in the opposite direction, i.e., so that the protruding outward of the concrete, it is possible to remove the fixed anchor in the concrete very easily. Further, unlike the conventional example, since no power tool or the like is used, it is safe, does not require a power source, and does not generate industrial waste such as concrete pieces. The anchor puller is a small part, is easy to carry, and has various excellent effects such that a large space is not required for storage.

Also, the dimension of the shaft portion is longer than the dimension from the end of the female screw portion to the upper end of the cone in the extension portion and shorter than the dimension of the extension portion.
Further, the size of the neck portion is longer than a size obtained by adding the size of the female screw portion and the size from the end portion of the female screw portion to the upper end portion of the cone in the expansion portion. The tip of the shaft can be securely contacted with the upper end of the cone by screwing the part into the female screw part, and in this state, the head of the anchor extractor is positioned at a required distance from the anchor Will be done. Therefore, since the head of the anchor puller is securely rotated and screwed in, an excellent effect that the anchor can be protruded in the direction opposite to the screwing direction is achieved.

[Brief description of the drawings]

FIG. 1 is a side view of an anchor puller according to the present invention.

FIG. 2 is a sectional view of an anchor.

FIG. 3 is a cross-sectional view illustrating a state where an anchor puller is screwed into an anchor fixed to concrete.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Anchor extraction tool 12 Head 13 Neck 14 Male screw part 15 Shaft part 15a tip 16 Tapered part 17 Anchor 18 Female screw part 18a end part 19 Expansion part 20 Body part 21 Cone 21a Upper end part 23 Slit 24 Tapered surface 25 Concrete

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kei Otsuka 3-11-3 Akasaka, Minato-ku, Tokyo Toda Construction Co., Ltd. Kanto Branch (72) Inventor Yuta Makino 3-11-3 Akasaka, Minato-ku, Tokyo Toda Construction Inside Kanto Branch (72) Inventor Masashi Koganezawa 3-11-3 Akasaka, Minato-ku, Tokyo Toda Construction Co., Ltd. Inside Kanto Branch (72) Koji Kumagai 3-11-3 Akasaka, Minato-ku, Tokyo Toda Construction Co., Ltd. Inside Kanto Branch (72) Inventor Yasuyuki Ueki 3-11-3 Akasaka, Minato-ku, Tokyo Toda Construction Co., Ltd. Kanto Branch F-term (reference) 2D041 GB02 2D050 AA16 AA18 DB01 2E176 AA01 DD61 3J025 AA08 BA34 CA03 EA01

Claims (2)

[Claims] 1. A cylindrical body having a female screw portion formed on an inner peripheral surface and a slit provided on a bottom portion, a main body having an expandable portion, and a cone inserted into the expandable portion. An anchor puller for pulling out the anchor from the concrete, the anchor puller comprising a head formed in a polygonal shape and rotatable with a wrench or the like, and a neck connected to the head, An anchor puller, wherein a male screw portion to be screwed with the female screw portion is formed on a base side of the neck portion, and a frustoconical or tapered shaft portion is provided on an end side of the neck portion. . 2. The dimension of the shaft is longer than the dimension from the end of the female screw to the upper end of the cone in the extension,
Further, provided that the dimension is shorter than the dimension of the extension, the dimension of the neck is the sum of the dimension of the female thread and the dimension from the end of the female thread in the extension to the upper end of the cone. The anchor puller according to claim 1, wherein the anchor puller is longer than a dimension.