JP2500921Y2 - Deployment sleeve for anchor bolt - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deploying sleeve used for an anchor bolt which is planted in a drill hole having an expanded hole portion called an undercut inside.

[0002]

2. Description of the Related Art In the case of mounting various structures on a surface to be planted, for example, a solidified concrete surface, a method is widely practiced in which anchor bolts are planted on the concrete surface and used.

As this anchor bolt, a bolt having a diameter-expanded portion having a taper surface which is downwardly expanded,
Corresponding to the expanded diameter part of this bolt, it is combined with a cylindrical deployment sleeve in which a deployment piece is formed by a slit at the bottom,
Expanded hole (undercut) in the inner part of the planted surface
The present applicant has proposed an anchor bolt that is inserted into a drill hole having a hole, expands a deployment piece on the expanded diameter portion, and presses the expanded piece against the expanded diameter portion wall to exert a strong fixing force.

The thicker the expansion sleeve used for this anchor bolt is, the more the expansion sleeve expands on the expanded diameter portion of the bolt to increase the amount of expansion so that the fixing force can be improved. If the slits are simply cut from the lower part of the sleeve in the axial direction, even if the distance between adjacent slits is reduced and the number of deployable pieces is increased, the deployable piece base that is bent when the deployable pieces are deployed bends in the circumferential direction. Therefore, not only a strong force is required for bending, but the deformation that occurs at the base of the expansion piece also extends to the expansion piece that expands on the expanded diameter part, and the state in which it touches the tapered surface Different for each
The pressure-bonding relationship with the wall of the enlarged diameter hole is not uniform, which greatly affects the pull-out strength.

Therefore, in the thick sleeve, the base of each deploying piece is easily bent, and a groove is circumferentially formed in the base of the deploying piece so as not to deform the deploying piece. There is also a structure in which the thickness of one base portion is thin.

[0006]

As described above, a slit formed in the lower portion of the developing sleeve in the axial direction from the lower end surface of the sleeve, and a groove hole formed in the circumferential direction at the developing piece base portion to form a wall thickness of the developing piece base portion. According to the thinned configuration, the slit cut in the axial direction from the lower end surface of the sleeve is a cutting process using a cutter, while the groove hole that is cut in the circumferential direction at the base of the developed piece is a cutting process using a lathe. Processing man-hours increase, leading to higher costs.

In the conventional method of forming a developed piece by mechanical cutting as described above, there is a limit to the width of the slit and the minimum width of the slot due to the relationship of the cutting tool, and the area of the developed piece becomes small and the diameter of the expanded piece increases. The force transmission area to the hole wall is reduced and the load per unit area is increased.

Further, in the cutting work of the groove hole in the developed piece base portion, a thin portion is formed between the groove hole bottom and the sleeve inner surface by cutting from the outer surface side of the sleeve by a lathe. When the deployment piece is bent outward from the thin part of the base part, it is limited by the groove hole width, and when the groove width is increased to increase the expansion amount of the deployment piece, the expansion piece area is further increased. Decrease.

The present invention has been made in view of the above points, and simplifies the process of forming the deploying piece of the deploying sleeve,
The purpose of the present invention is to provide a reliable deployment sleeve for anchor bolts that deploys the deployment piece comfortably at the time of planting to increase the force transmission area to the wall of the expanded hole and maintains stable planting strength. To do.

[0010]

The gist of the present invention for achieving the above object is to provide a bolt having an enlarged diameter portion having a downwardly widening tapered surface on the lower portion and a slit on the lower portion. An anchor bolt which is composed of a tubular expansion sleeve formed by forming a plurality of expansion pieces divided in the direction, and in which the expansion piece is expanded on the expanded diameter portion, the expansion piece of the expansion sleeve is a slit cut from the lower end surface of the sleeve. And a deployment sleeve for an anchor bolt, which is formed by a slit cut in a discontinuous manner in the circumferential direction, and the deployment piece base is connected to the sleeve main body through a thin connection portion whose thickness in the circumferential direction is thin. .

[0011]

[Action] multiple deployments pieces were Katachi設in the lower sleeve, circumferential direction
Since it is connected to the sleeve body through a thin connecting part with a thin thickness , the anchor bolt can be planted to insert it into a drill hole that has a diameter expansion hole (undercut) inside, The expansion piece on each part is bent by deformation of only the thin wall connecting part formed on the base part of each expansion piece, and each expansion piece is expanded while maintaining its original shape and attached to the taper surface of the expanded diameter part, and the drill hole Uniformly crimps to the wall of the expanded hole of to demonstrate a strong fixing force.

[0012]

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

FIG. 1 is an exploded perspective view of an anchor bolt using this invention.

In the figure, A indicates an anchor bolt,
The main part is composed of a bolt 1 and a tubular expansion sleeve 2 fitted to the bolt 1.

The bolt 1 is provided with a diameter-expanded portion 4 having a taper surface 3 which extends downward at the lower portion thereof, and a mounting screw 5 at the upper portion thereof. The deploying sleeve 2 has a plurality of deploying pieces 7 formed by cutting a slit 6 in a T-shape from the lower end surface of the deploying sleeve 2, and each deploying piece is formed by a slit 6'which is discontinuous in the circumferential direction at the base of the deploying piece 7. 7 is connected to the sleeve body 2'through a thin connecting portion 8 having a reduced thickness in the circumferential direction .

In the above embodiment, the developing sleeve 2
Each development piece 7 is connected to the sleeve body 2'by one thin connecting portion 8 by the T-shaped slit 6,
As shown in FIGS. 3 (a) and 3 (b), the shape of the slit is such that each developing piece 7 is connected to the sleeve main body portion 2'by two thin connecting portions 8.
May be connected.

The expanding piece 8 is formed by laser processing or water jetting in the case of the expanding sleeve 2 which is a cylindrical body. As shown in FIG. 4, the flat piece is pressed. After forming the slit 6 by punching, the developing sleeve 2 may be finished by bending it into a cylindrical shape.

Further, the curvature of the inner peripheral surface of each deploying piece 7 of the deploying sleeve 2 in the transverse direction of each part is small at the base of the deploying piece 7 so as to match the taper surface 3 of the expanded diameter portion 4 in advance. The curvature is gradually increased toward the tip (lower end).

In the above construction, in order to plant the anchor bolt A on the planted surface B such as the concrete floor surface, the following work procedure is used.

(A) The expansion sleeve 2 is fitted on the bolt 1, and the expansion sleeve 2 is previously inserted into the drill hole C having the enlarged diameter hole portion C'in the inner side of the planted surface B.

(B) When a hammering rod is used at the lower end, the bolt 1 is loosely inserted, and this is hit against the sleeve 2 and hammered,
The expanded portion 4 is press-fitted into the lower portion of the sleeve 2 so that each deployment piece 7
In the enlarged diameter portion C ′, the base portion is bent from the thin connecting portion 8 having a reduced thickness in the circumferential direction and is expanded on the enlarged diameter portion 4.

(C) When the upper end of the bolt 1 is inserted into the mounting hole D'drilled in the structure D mounted on the planted surface B, the nut 9 is screwed into the mounting screw 5, and the nut 9 is screwed in. The bolt 1 is pulled up in the drill hole C and expanded on the expanded diameter portion 4, and each expanded piece 7 is pressed against the hole wall of the expanded diameter portion C'and the inner surface of each expanded piece 7 is a tapered surface of the expanded diameter portion 4. Exactly attach to 3.

[0023]

According to the present invention constructed as described above,
The following effects are obtained.

(I) Since the slits for forming the expansion pieces on the lower part of the expansion sleeve can be formed at the same time by laser processing, press punching, etc., it is possible to reduce the processing man-hours and simplify the processing cost.

[0025] (ii) each expansion piece, circumference have you at its base
Since it is connected to the sleeve body with a thin connecting part with a thin thickness in the direction, it does not require a strong force to bend this thin connecting part when the deployment piece is deployed, and the bending amount is also limited. Without deploying the deployment piece, the anchor bolt can be easily planted.

(Iii) Since the width of the slit formed by laser processing or press punching can be made smaller than that formed by mechanical cutting, the area of the developed piece can be increased and the diameter of the drill hole can be increased. It is crimped to the wall to reduce the weight per unit area.

(Iv) Since the bending of the thin-walled connecting portion at the base of the developing piece does not affect the shape of the developing piece when the developing piece is expanded, each developing piece maintains its original shape regardless of the wall thickness of the sleeve. The taper surface of the diametrically expanded portion is closely contacted and uniformly pressed to the wall of the diametrically expanded portion of the drill hole to exert a strong fixing force.

[Brief description of drawings]

1 is an exploded perspective view of an anchor bolt using the present invention. 2 is a cross-sectional view of the thin connecting portion of the deployment sleeve. 3 (a) and 3 (b) are front views of a developing sleeve showing a modified embodiment. 4 is a development view of a deployment sleeve showing another modified embodiment. 5 is a vertical sectional view showing a mode of use of the present invention.

[Description of sign]

 1 ... Bolt 2 ... Expansion sleeve 3 ... Tapered surface 4 ... Expanded part 6 ... Slit 7 ... Expansion piece 8 ... Thin-walled connection part A ... Anchor bolt B ... Plant surface C ... Drill hole

Claims (1)

(57) [Scope of utility model registration request] 1. A bolt having a diameter-expanded portion having a taper surface that extends downward at a lower portion, and a tubular expansion sleeve having a plurality of expansion pieces circumferentially divided by slits at the bottom, In the anchor bolt for deploying the deployable piece on the expanded diameter portion, the deployable piece of the deployable sleeve is formed by a slit cut from the lower end surface of the sleeve and a slit cut discontinuously in the circumferential direction, and the deployable piece base is circumferentially formed.
A deployment sleeve for an anchor bolt, characterized in that it is connected to the sleeve body through a thin connecting portion whose thickness is reduced in the horizontal direction .