JP2000192552A - Embedded insert - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively provide an embedded insert having a female screw part for installing a hook bolt and an eye bolt used for suspending/reversing a PC plate. SOLUTION: A thick steel pipe is cut in the prescribed length to be formed as an insert member 11, and a female screw part 2 is carved toward the other end part from the one end part. In the other end part of the insert member, a boring part 4 becoming a part thinner in a thickness than the female screw part is formed by boring work. This boring part is pressed by a molding punch 12, and a peripheral part is push-expanded to form a flange part 3. Thus, an embedded insert S easy in machining since the total length is short and having large embedding strength to a concrete surface can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an embedding insert which is embedded in a concrete wall so that a hook bolt or an eye bolt used for moving or reversing a scaffold for construction of a building, a steel foundation or PC concrete can be detachably mounted.

[0002]

2. Description of the Related Art When constructing scaffolds, foundations, and the like, and constructing scaffolds, foundations, and the like, for example, inverting and suspending PC girders, and removing molds, it is necessary to attach hook bolts, eye bolts, and other members. Is often removed after it has fulfilled its predetermined purpose because it is no longer needed.

[0003] Accordingly, such hook bolts and the like are attached only when used for a specific application, and are detachable by screwing these members into a concrete wall surface so that they can be removed at other times. The threaded portion of these members is provided with a threaded portion, and an insert with a threaded portion is embedded in the concrete wall in advance, and can be detached by screwing and disengaging the threaded portion with the threaded portion. There is. Since a large pull-out force acts on the insert via a bolt that is screwed, various means are employed to withstand this. As described above, there are the following inserts to be embedded in the concrete wall surface.

(A) A pilot hole is drilled in a concrete wall surface, an insert member having a female thread at one end and a wedge inserted into a hollow portion at the other end is driven into the hole, and the other end is pushed and expanded by a wedge. By increasing the frictional resistance to increase the bonding force, it is difficult to remove.

(B) An insert member having a female thread at one end of a deformed reinforcing bar of a predetermined length is buried in advance so that one end thereof is flush with a concrete wall surface. What is raised.

(C) A transverse hole perpendicular to the axis is provided in the vicinity of the other end of an insert member made of a reinforcing bar having a predetermined length and having a female thread at one end, and a holding member of a predetermined length is penetrated therethrough. One that increases the bonding strength of the insert member and makes it difficult to remove.

(D) A plate material is welded to the other end of the insert member having a female thread to increase the bonding force of the insert member.

(E) Similarly, the other end of the insert member having a female thread is provided with a skirt by forging to increase the bonding force of the insert member.

[0009]

In the prior art (a), the construction work at the construction site is increased and the work is troublesome. In addition, since the work is held by frictional force, the connecting force of the insert member is increased. There are disadvantages that cannot be achieved.

[0010] (b) has a drawback that it cannot be applied to a thin wall surface because a large coupling force cannot be obtained unless the insert member is long.

[0011] (c), (d) and (e) provide a large coupling force, but have the disadvantage of increasing the processing cost of the insert member.

SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive insert which has a large bonding force to a concrete surface and is easy to construct.

[0013]

In order to achieve the above-mentioned object, an embedded insert according to the present invention has a female threaded portion formed in an arbitrary range from one end to the other end of a thick pipe having a predetermined length. The other end is formed with a flange part integral with the pipe, so that it is difficult to come off when buried in concrete or the like, thereby increasing the bonding force and reducing the manufacturing cost.

This embedded insert is desirably made of metal such as steel. In this case, a female thread is cut at one end of a thick steel pipe, and the other end is expanded by using a press or the like. The flange portion can be easily formed.

As described above, when the embedded insert is made of a metal such as a thick steel pipe, the processing of the flange portion is performed at least in a range where the internal thread portion is engraved in a range provided for the expanding process. The processing is facilitated by making the thickness thinner than the thickness.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the embedded insert S has a cylindrical body 1 in which an internal thread 2 is provided from one end to the other end, and a flange 3 is provided in the other end. Become.

The body 1 is formed by using a thick pipe without processing the outer periphery, and one end of the body (the upper part in FIG. 1).
An internal thread portion 2 is engraved on the inner diameter portion of the thick pipe by tapping or the like toward the other end of the thick pipe. At the entrance of the female screw part 2, a guide part 2a formed by burring a dish is formed to facilitate the screwing of the male screw.

The flange 3 formed at the other end (lower part of the drawing) of the body 1 is formed integrally with the body 1 by expanding the other end of the steel pipe as described later. A boring portion 4 having a large inner diameter formed by boring is formed in the inner diameter portion of the portion where the flange portion 3 is formed. The boring portion 4 serves as a space for a relief portion at the time of female thread cutting, and at the same time, has a function of facilitating the pipe expanding process for forming the flange portion 3.

FIG. 2 shows an example of a method for processing an embedded insert according to the present invention. As shown in FIG. 1A, a thick steel pipe whose inner diameter matches the inner diameter of the internal thread portion 2 is cut into a predetermined length to form an insert material 11, and a guide portion 2a is formed at one end (upper end) by dishing. Form. The other end is formed with a boring portion 4 by expanding the inner diameter to a predetermined length range by boring.

Next, one end is fixed by a die holder (not shown), and is pressed from the other end by a forming punch 12 so as to be sequentially spread from the other end of the boring portion 4 to substantially extend the body 1. The flange 3 is formed so as to be in a vertical state.

Next, when the punch 12 is retracted and the processed product is taken out from the holder, an embedded insert S as shown in FIG. 2B is completed. Although the shape of the embedded insert S is slightly different from that shown in FIG. 1A, various shapes should be prepared depending on the application.

In addition, as for the method of processing the insert member, in addition to the above example, various methods including a method of processing the whole by forging a round steel material can be selected. Further, the material, size, shape, and the like of the insert member can be selected according to the construction needs.

FIG. 3 shows an application example of the present invention, in which an embedding insert S is embedded to detachably attach a carrying eye bolt 14 to a PC board 13. Before the embedding, a blind plate 1
By fixing 5, foreign substances can be prevented from entering the female screw portion at the time of embedding. Instead of the above-mentioned blind plate, a resin cap may be put on the boring portion 4 at the opening end.

The eyebolt 14 is attached during transportation and construction, and is removed when it is not needed, so that it is not in the way. By installing various bolts to make hook bolts, anchor bolts, scaffolds, etc. in place of these eye bolts, it is possible to lift / reverse / remove PC boards and PC girders, to connect PC boards, and to connect PC girders. It can be applied to scaffolding, building construction scaffolding, building wall construction and a wide range of other uses.

[0025]

According to the present invention, an embedding insert having a high embedding strength in concrete can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing an example of an embodiment of the present invention.

FIGS. 2A and 2B show a processing method of the present invention, in which FIG. 2A is an explanatory view showing a state before processing, and FIG. 2B is a cross-sectional view showing a state after processing.

FIG. 3 is a sectional view showing an example of use of the present invention.

[Explanation of symbols]

 S Embedded insert 1 Body 2 Female thread 3 Flange

Claims (3)

[Claims] 1. A thick pipe having a predetermined length is provided with a female thread from one end to the other end, and a flange integral with the pipe is formed at the other end. Embedded insert characterized by the following. 2. A thick metal pipe cut to a predetermined length is provided with a female thread from one end to the other end, and a flange is formed at the other end by a pipe expanding process. An embedded insert formed integrally with a pipe. 3. The method according to claim 2, wherein the other end has a thickness at least in a range provided for the pipe expanding process is smaller than a thickness in a range in which the female screw portion is engraved. Embedded inserts to feature.