JPH06313413A - Screw fixing auxiliary tool to concrete or the like - Google Patents

Abstract

PURPOSE:To provide a screw fixing auxiliary tool by which coupling by means of a tapping screw can be conducted simply and firmly. CONSTITUTION:An underhole (d) into which a tapping screw 5 is screwed, is formed at concrete (a), and a screw fixing auxiliary tool 1 that does not fill the whole periphery of the inner periphery surface of the underhole (d) is arranged along the inner periphery surface, and by making the screw thread of the taping screw 5 screwed into the underhole (d) bite into the concrete (a) and a body portion 2, coupling that is firm and does not run idle is made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw fixing auxiliary tool for fixing various members to concrete or the like by using tapping screws.

[0002]

2. Description of the Related Art For fixing various members to, for example, concrete, ALC (cellular concrete), gypsum board, etc., fastening means depending on the material have been proposed, but fastening with tapping screws is recommended. It's easy and inexpensive.

Conventionally, in order to fix various members to concrete, a tapping screw is screwed into a pilot hole provided in the concrete for fastening, or a plug and an anchor are embedded in the concrete, and screws are screwed into this for fastening. Also,
To fix various members to the ALC, plugs and anchors dedicated to the ALC are embedded, and screws are screwed into the ALC to fasten them, or special nails of an open leg type or the like are driven and fastened.

Further, a dedicated plug and anchor are embedded in the gypsum board, and a screw is screwed into this and fastened.

[0005]

By the way, the method of directly screwing the tapping screws into the concrete and fastening them is as follows.
If the inner diameter of the prepared hole formed by the drill is too large with respect to the screw thread diameter of the tapping screw, it may idle during fastening, and if it is too small, screwing of the tapping screw becomes difficult.

Further, since the materials of ALC and gypsum board are fragile, when the tapping screw is directly screwed in, the portion where the screw thread bites is immediately broken, and the screw often does not work.

Further, in the method of fastening by using the plug and the anchor, as illustrated in FIG. 3, the plug 22 or the anchor is inserted into the pilot hole 21 provided in the member 31 to be screwed, and the tap 22 or the anchor is tapped. Screw in and fasten.

The plug 22 has a step portion 23 on its outer peripheral surface for preventing the plug from coming off.
By forming a tapping screw screw hole 24 from one end side to the middle along the axial center, dividing the other end side into a plurality of slits 25 from the middle, and screwing the tapping screw into the screw hole 24, the slit is formed. The portion divided by 25 is expanded to obtain a stopper for the plug 22 and the tapping screw fastened thereto, and the anchor has a substantially similar structure.

In such a fastening method using the plug 22 and the anchor, the tapping screw is screwed into the plug 22 and the anchor inserted into the prepared hole 21 of the member 31 to be screwed, so that the tapping screw is directly attached to the member 31 to be screwed. There is no occurrence of a screw-in portion. Therefore, in the initial stage of screwing in the tapping screw, the plug 22 and the anchor may rotate together, which may make fastening impossible. Occurs in.

Further, the use of the plug 22 and the anchor is not only costly but also troublesome in construction.

[0011] Therefore, an object of the present invention is to provide a screw fixing auxiliary tool to concrete or the like that can be firmly fastened using tapping screws regardless of the material of the member to be screwed.

[0012]

In order to solve the above-mentioned problems, the first invention comprises a substantially semi-cylindrical body having a semicircular cross section or less, and the outer periphery of the body on the head side. A collar-shaped enlarged diameter portion is provided, and the body portion adopts a configuration in which the content gradually increases from the head side to the tip side.

The second aspect of the present invention employs a configuration in which a body is formed with a cylindrical cross section and an eccentric inner hole, and a head is provided on the outer circumference of one end of the body. The internal hole may be formed as a tapered hole.

[0014]

[Action]

1st invention Put an attachment object on the wall surface of concrete, after making a pilot hole in the concrete from the attachment hole provided in the attachment object, insert a screw fixing aid into the pilot hole, and then Screw a tapping screw from the mounting hole into the pilot hole with a screwdriver.

The tapping screw has a screw thread that penetrates into both the body and the concrete, and the body is strongly pushed against the inner circumference of the pilot hole by the penetration of the screw to prevent the occurrence of idle rotation. It prevents the formation of a gap in the inner circumference, which ensures that the screw threads bite into both the concrete and the body, and a strong fastening can be obtained even with concrete, ALC or gypsum board.

Second invention: As in the first invention, a screw fixing aid is inserted into the prepared hole of the concrete, and the tapping screw is screwed into the inside hole by a screwdriver or the like. Since it is eccentric with respect to the outer circumference of the part, the screw thread penetrates the thin wall part of the body peripheral wall and forms a female screw even to the inner wall of the concrete, and at the thick part, the body part is screwed. Is strongly pressed against the concrete inner wall by the intrusion of
In this way, the screws are difficult to insert into both the body and concrete.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. 1 and 2 of the accompanying drawings.

The screw fixing auxiliary tool 1 of the first embodiment shown in FIG. 1 is composed of a substantially semi-cylindrical body portion 2 having a semi-circular cross section or less, and a collar-shaped outer periphery of the body portion 2 on the head side. The enlarged diameter portion 3 is provided, and the body portion 2 has a thickness that gradually increases from the head side to the tip side.

The body 2 has a substantially semi-cylindrical cross section,
The arcuate concave portion 4 formed on the flat surface side gradually becomes shallower from the head side toward the tip, whereby the peripheral wall of the body portion 2 becomes thinner at the head side and gradually becomes thicker toward the tip side. Has become.

The outer diameter, inner diameter and length of the body 2 may be set according to the tapping screw 5 to be used, and the screw fixing aid 1 is made of various synthetic resins or metals such as lead. Can be formed.

The screw fixing aid of the first embodiment has the above-mentioned structure, and the object b to be mounted is put on the wall surface of the concrete a, and the concrete a is drilled through the mounting hole c of the object b. Then, a pilot hole d having a diameter slightly larger than the root diameter of the shaft portion 6 of the tapping screw 5 is bored, and the body portion 2 of the screw fixing auxiliary tool 1 is inserted into the pilot hole d.

At this time, the screw fixing aid 1 is prevented from entirely falling into the prepared hole d by the contact of the expanded diameter portion 3 provided on the head side with the concrete wall surface.

Next, when the tapping screw 5 is screwed into the lower hole d with a screwdriver or the like, as shown in FIGS. 1 (D) and 1 (E),
The male screw 7 formed on the shaft portion 6 of the screw 5 is difficult to be inserted into both the inner peripheral surface of the body portion 2 and the inner peripheral surface of the prepared hole d of the concrete a.

Since the body portion 2 has a substantially semi-cylindrical shape whose cross section is semicircular or less, and the wall thickness gradually increases toward the tip side, the body portion 2 is made of concrete a due to the tapping screw 5 entering. The screw fixing aid 1 is prevented from idling even when the screw 5 is screwed in by being strongly pressed by the inner surface of the pilot hole.

The male screw 7 of the tapping screw 5 bites into both the body 2 and the concrete a, and the male screw 7 in which the body 2 is difficult to fit is flexibly clamped, so that the idling of the tapping screw 5 is prevented. When a pulling force is applied after fixing, the male screw 7 in which the concrete a is difficult to stick is firmly fixed and exhibits momentary strength, and at the same time, the male screw 7 in which the body 2 is hard to receive flexibly receives the pulling force to cause vibration or long-term It can withstand the strength. By the way, compared with the case where only tapping screws are fixed, the total pull-out strength is about double when the same hole diameter is used.

Next, the screw fixing aid 11 of the second embodiment shown in FIG. 2 comprises a body portion 13 having a cylindrical cross section and an eccentric inner hole 12, and one end portion of the body portion 13 is formed. A head portion 14 is provided on the outer periphery of the body portion 13, and the thin wall portion 15 and the thick wall portion 16 are opposed to each other on the peripheral wall of the body portion 13 with the eccentricity of the hole 12 sandwiching the axial center.

The inner hole 12 is open on the head side of the body portion 13 and closed on the tip side. The hole 12 may be straight, but as shown in the drawing, it is a tapered hole whose diameter gradually decreases on the tip side. In this case, both the thin wall portion 15 and the thick wall portion 16 gradually increase in thickness toward the tip side.

The outer diameter and length of the body portion 13 and the inner diameter of the hole 12 may be set according to the tapping screw 5, and the material for forming the screw fixing aid 11 is synthetic resin or metal such as lead. You can use it.

The screw fixing assisting tool 11 of the second embodiment has the above-mentioned structure, and like the first embodiment, the inner hole pilot hole d for fitting the body portion 13 into the concrete a is formed. Then
The body 13 of the screw fixing aid 11 is inserted into the lower hole d, and then the tapping screw 5 is screwed into the hole 12 of the body 13 with a screwdriver or the like.

The shaft portion 6 of the tapping screw 5 rotationally enters the inner peripheral surface of the hole 12 while forming a female screw with the male screw 7, and the thin screw portion 15 of the body 13 has the male screw 7 cut through and protrude to form the male screw. 7 advances while forming an internal thread by fitting into the inner peripheral surface of the pilot hole d of concrete a.

In the thick-walled portion 16 of the body 13, the male screw 7 is pushed into the inner surface of the prepared hole d of the concrete a by the male screw 7, and thus the male screw 7 of the tapping screw 5 is Both the part 13 and the concrete "a" are hard to be inserted, and strong fixation with strong pull-out resistance can be obtained as in the case of the first embodiment described above.

[0032]

As described above, according to the present invention, by inserting the screw fixing aid into the prepared hole of the concrete and screwing the screw, the male screw of the screw is inserted into the body of the concrete and the assist tool, and the prepared hole On the other hand, the shaft portion of the screw can be screwed in without any play, so that the object to be attached can be firmly and firmly fastened to concrete or the like, and fixation with strong pull-out strength can be obtained.

Further, since the body of the screw fixing aid is made to lie along a part of the inner peripheral surface of the lower hole or the hole of the body is eccentric, the screw thread of the screw bites into both the body and the concrete. Also, there is no co-rotation of the body, and even if the member to be screwed is a fragile material, the screw can be securely fastened, and it is cheaper than conventional plugs and anchors, and the construction cost is low. At the same time, the construction work can be significantly shortened.

[Brief description of drawings]

1A is a perspective view showing a first example of a screw fixing aid, FIG. 1B is a plan view, FIG. 1C is a longitudinal sectional view, and FIG. 1D is a longitudinal sectional view of a fastening state using the same. Figure, (E) is a cross-sectional view of the fastening state

2A is a perspective view showing a second example of a screw fixing aid, FIG. 2B is a vertical front view of the same, FIG. 2C is a cross-sectional plan view thereof, and FIG. Longitudinal sectional view of the state, (E)
Is a cross-sectional view of the tightened state

FIG. 3 is a vertical sectional view showing an example of using a plug which is a conventional fastening method.

[Explanation of Codes] 1, 11 Screw fixing aid 2, 13 Body part 3 Expanded part 4 Recessed part 5 Tapping screw 6 Shaft part 7 Male screw 12 hole 14 Head part 15 Thin wall part 16 Thick wall part a Concrete d lower hole

Claims (3)

[Claims] 1. A substantially semi-cylindrical body having a semi-circular shape or less in cross section, and a collar-shaped expanded portion is provided on the outer circumference of the body on the head side.
The body fixing portion has a gradually increasing content from the head side to the tip side, and the screw fixing aid to concrete or the like is characterized in that. 2. A screw fixing aid for concrete or the like, which comprises a body having a cylindrical cross section and an eccentric inner hole, and a head is provided on the outer periphery of one end of the body. . 3. A screw fixing aid for concrete or the like according to claim 2, wherein the internal hole is formed as a tapered hole.