JPH10266464A - Connecting device for threaded reinforcing bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connecting device such that the engaged depth of a threaded reinforcing bar in a joint can be checked without marking the threaded reinforcing bar. SOLUTION: A pair of threaded reinforcing bars 1 to be connected have their ends engaged with a cylindrical joint 10. An inspection hole 12 and an injection hole are formed in the longitudinal center of the circumferential wall of the joint 10. The inspection hole 12 extends longitudinally. The injection hole separates circumferentially from the inspection hole 12. Therefore, prior to injection of a grout, engagement of the threaded reinforcing bar 1 by the required engagement depth is verified if the end 1a of the threaded reinforcing bar 1 can be seen from the inspection hole 12. Then, the grout is injected from the injection hole while a cap 20 made of a transparent, elastic resin material is fitted in the inspection hole 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting device for a screw rebar which secures connection strength by injecting a grout material into a joint.

[0002]

2. Description of the Related Art As shown in FIG. 8, in a threaded bar connecting device, ends of a pair of threaded bars 1 to be connected are screwed into a cylindrical joint 2 and then grout material ( (Not shown) is injected to secure the connection strength. More specifically, first, as shown in FIG. 8A, the joint 2 is screwed to one of the threaded rebars 1 and the other threaded rebar 1 is abutted or brought close to the same straight line. As shown in (B), the joint 2 is turned, and about half of the joint 2 is screwed into the threaded reinforcing bar 1 of the other party. In this state,
A grout material is injected from an injection hole 3 formed in the center of the joint 2. Then, the connection work of the screw reinforcing bar 1 is completed with the hardening of the grout material.

[0003] In order to obtain a sufficient connection strength between the screw rebars 1, it is necessary to set the screwing depth of each screw rebar 1 to the joint 2 to a predetermined amount or more. Therefore, conventionally, a marking 5 extending in the longitudinal direction with paint or the like is provided at a position away from the tip 1a of the screw reinforcing bar 1. Distance D ₁ of the between one end (the end closer to the leading end 1a of the screw rebar 1) and the tip 1a of the screw reinforcing bar 1 of the marking 5 is equivalent to the necessary screwing depth. Distance D ₂ between the other end and the threaded rebar 1 tip 1a of the marking 5 is equivalent to engagement depths prohibit any further screwing. This is for securing the necessary screwing depth of the screw reinforcing bar 1 of the other party. Therefore, a state where both ends of the joint 2 are at positions corresponding to the markings 5 of the double-threaded reinforcing bar 1,
That is, if the grout material is injected with a sufficient screwing depth secured, a sufficient connection strength can be secured. In addition, when the connection state is inspected at a later date, the marking 5
The screwing depth of the threaded rebar can be confirmed from the positional relationship between the screw and the two ends of the joint 2.

[0004]

As described above, conventionally, in order to confirm the screwing depth of the threaded rebar 1, the threaded rebar 1
However, the operation of applying the markings 5 has to be applied or sprayed with a paint using a jig or the like, and requires a lot of labor and is very troublesome.

[0005]

The invention of claim 1 has a joint, and grout material is injected into the joint in a state where ends of a pair of threaded steel bars are screwed to the joint. In the apparatus for connecting threaded reinforcing bars, an inspection hole formed of a long hole extending in the longitudinal direction is formed at the center in the longitudinal direction of the peripheral wall of the joint to confirm the tips of both threaded reinforcing bars. An injection hole for injecting the grout material at a distance in the direction is formed, and a cap for closing the inspection hole when the grout material is injected into the injection hole is provided.

According to a second aspect of the present invention, there is provided a joint, and in a state in which the ends of a pair of threaded rebars are screwed to the joint, grout is injected into the joint to connect the threaded rebars. In the apparatus, an inspection hole made of a long hole extending in the longitudinal direction is formed at the center in the longitudinal direction of the peripheral wall of the joint to confirm the tips of both screw rebars, and further, when the grout material is injected, the inspection hole is formed. A cap for closing the hole, and an inlet for injecting the grout material is formed in the cap.

According to a third aspect of the present invention, in the connecting device for a screw rebar according to the first or second aspect, the cap is formed of a transparent material. According to a fourth aspect of the present invention, in the connecting device for a screw rebar according to any one of the first to third aspects, the cap is formed of an elastic material.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a connecting device for a screw rebar according to an embodiment of the present invention. The joint 10 used in the present embodiment has a long nut shape (cylindrical shape) with a hexagonal cross section, and has a female screw 11 for screwing the screw reinforcing bar 1 on the inner periphery. In addition, an inspection hole 12 and an injection hole 13 are formed at a longitudinally central portion of the peripheral wall of the joint 10 so as to penetrate the peripheral wall.

The inspection hole 12 is for visually recognizing the distal ends of the two screw reinforcing bars 1 from the outside, and is formed by a long hole having a length L extending in the longitudinal direction. The distance D from both ends of the inspection hole 12 to both ends 10a of the joint 10 is equal. This distance D corresponds to the minimum required screwing depth of the screw reinforcing bar 1.

The injection hole 13 is for injecting a grout material, and is a circular hole. The nozzle tip of a grout injection jig (not shown) is inserted into the injection hole 13. This injection hole 13 is used for the inspection hole 12.
The joint 10 is formed at a position away from the joint 10 in the circumferential direction.
In the present embodiment, these inspection holes 12 and injection holes 13 are
The outer peripheral surface of the joint 10 is provided on an adjacent flat surface 10b.

The connecting device for a screw rebar further includes a cap 20 for closing the inspection hole 12. In the present embodiment, the cap 20 is made of an elastic material such as a transparent elastic resin or rubber, and has a slightly larger cross-sectional shape similar to the cross-sectional shape of the inspection hole 12.

In the above configuration, when connecting a pair of threaded reinforcing bars 1, first, the joint 10 is screwed to one threaded reinforcing bar 1 over the entire length, and the other threaded reinforcing bar 1 is arranged on the same straight line. At the same time, the end faces of the screw rebars 1 are brought into contact with each other or brought close to each other. In this state, the joint 10 is turned, and about half of the joint 10 is screwed into the other threaded reinforcing bar 1. Note that the joint 10 may be screwed to the joint 10 by turning the other screw reinforcing bar 1 in a state where the joint 10 is half screwed to the one screw reinforcing bar 1.

Next, looking through the inspection hole 12 of the joint 10,
Check whether the tips of both threaded rebars 1 are visible.
If it can be seen, it is determined that both threaded rebars 1 are screwed to the joint 10 with the required screwing depth secured, and the process proceeds to the next grout injection step. Both from inspection hole 12, or
If one of the threaded rebars 1 is not visible, it is determined that the required threading depth is not attained.
Advance until the tip is visible from the inspection hole 12.

When the screwing is completed, the cap 20 is pressed into the inspection hole 12 of the joint 10 as shown in FIG. Then, the inner end of the cap 20 is deformed corresponding to the screw thread of the screw reinforcing bar 1, and the inner end surface is in close contact with the outer peripheral surface of the screw reinforcing bar 1. Next, a grout material (not shown) such as cement milk or filler-filled epoxy resin is injected through the injection hole 13.
To complete the connection work. In this embodiment, it is assumed that such an opaque grout material is used.

In the present embodiment, the cap 20 is left as it is fitted in the inspection hole 12. Since the outer periphery of the screw reinforcing bar 1 and the inner end surface of the cap 20 are in close contact with each other, the grout material does not enter between them, and the positions of the tips of both the screw reinforcing bars 1 can be confirmed from outside through the transparent cap 20 later. . Therefore, even in the inspection after the construction, the screwing depth of the screw rebar can be confirmed.

FIG. 5 shows another embodiment of the present invention.
This will be described with reference to FIGS. In these embodiments, it is assumed that the grout material is opaque, that the cap 20 is left in the inspection hole 12 after the grout material is injected, and that the screw depth is inspected later.

The cap 20A shown in FIG. 5A is composed of a transparent hard resin 21 and a transparent elastic resin 22. This elastic resin 22 hits the outer periphery of the screw rebar and deforms and adheres. The cap 20B shown in FIG. 5 (B) is formed of a transparent elastic resin, and has a concave portion 23 which is opened on an outer surface (a surface remote from the screw rebar). Make it thinner to ensure more transparency. The cap 20C shown in FIG. 5C is made of a transparent hard resin, and has an inner surface (a surface facing the screw reinforcing bar 1) formed with a groove 24 that is continuous with the female screw 11 of the joint 10. With the cap 20C fitted in the inspection hole 12 of the joint 10, the groove 24 fits into the thread of the threaded rebar 1 and the two closely adhere. Note that an elastic resin layer may be provided on the inner end surface of the cap 20 </ b> C to enhance the adhesion to the outer peripheral surface of the screw reinforcing bar 1.

FIGS. 6 and 7 show that the joint 10 has an inspection hole 12.
FIG. 4 shows a cap that is used in the case of having only a grout and not having a grout injection hole. Describing a specific example, the cap 20D shown in FIG. 6 is made of a transparent elastic resin, and an injection hole 25 is formed in the center thereof. Also, this cap 20
A groove 26 extending in the longitudinal direction is formed on the surface facing the screw reinforcing bar 1 of D. When the grout material is injected from the injection hole 25 in a state where the cap 20D is fitted into the inspection hole 12 of the joint 10 and is in close contact with the screw reinforcing bar 1, the grout material passes through the groove 26 and smoothly connects with the screw reinforcing bar 1. Filled in 10 gaps. The cap 20E shown in FIG.
Is made of a transparent hard resin like the cap 20C shown in FIG.
A spiral groove 24 is formed on a surface facing the screw reinforcing bar 1. Further, a grout material injection hole 27 is formed at the center, and a grout material passage groove 28 extending in the longitudinal direction is formed on a surface facing the screw reinforcing bar 1.

The cap 20D of FIG. 6 may be modified in the same manner as the caps 20A and 20B of FIG. 5, or a thin elastic resin layer may be provided on the inner end surface of the cap 20E of FIG. When the screw rebar 1 is screwed into the joint 10 in a state where the tips of the threaded rebars 1 are separated from each other, the caps 20D, 2
The grout material can be injected smoothly without the grout material passage grooves 26 and 28 of 0E.

The caps 20, 20A to 20E may be removed from the inspection hole 12 of the joint 10 after filling the grout material. In this case, it is possible to directly inspect the threaded state of the threaded rebar 1 through the inspection hole 12 after the connection operation is completed. In order to remove these caps, a handle portion protruding from the outer periphery of the joint may be formed on the cap, or a flange that contacts the outer peripheral surface of the joint may be formed. When the cap is removed in this manner, the cap may be formed of an opaque material.

The present invention is not limited to the above embodiment, and various forms are possible. For example, if it is not necessary to inspect the threaded state of the screw reinforcing bar after the grouting material is injected and the connection operation is completed, the cap is formed of an opaque material,
It may be left in the inspection hole of the joint. Further, since the grout material may cover the vicinity of the distal end of the screw reinforcing bar, the cap may be separated from the outer periphery of the screw reinforcing bar. Also, therefore, a hard cap may be used that does not have a groove on the inner end surface that matches the thread of the threaded rebar.

In the case where the grout material is a transparent resin, even if the grout material enters between the cap and the outer periphery of the screw rebar, the position of the tip of the screw rebar can be inspected after the grout material is injected. Therefore, in this case,
The cap may be separated from the screw rebar in the state where the inspection hole is fitted, and may be rigid. If the joint has an injection hole, the cap may be formed by filling the inspection hole with a liquid material and solidifying it before the grout material injection. In this case, if the material is transparent, the screwing depth can be inspected even after the connecting operation. In the case of a cap with an injection hole, this cap may be used as a nozzle of an injection jig. In this case, the cap is removed from the inspection hole after grout filling is completed. A soft (plastic) material may be used instead of the elastic material used for the cap. Lock nuts may be used at both ends of the joint 10.

[0023]

As described above, according to the first and second aspects of the present invention, the tip position of the screw rebar can be externally confirmed through the inspection hole provided in the joint before the grout material is injected. It is possible to easily confirm whether or not the screw rebar is screwed at the required screwing depth. Therefore,
Sufficient connection strength can be ensured despite the tedious work of marking threaded reinforcing bars. According to the first aspect of the present invention, since the injection hole is formed at the joint away from the inspection hole, the shape of the cap fitted into the inspection hole can be simplified. According to the second aspect of the present invention, since the grout injection hole is provided in the cap, the injection hole does not need to be provided in the joint, and the number of processing steps of the joint can be reduced. According to the invention of claim 3, since the cap is made of a transparent material, the position of the tip of the screw rebar can be visually checked from the outside after the grout material is injected while the cap is left in the inspection hole, Inspection of screw depth after construction is possible. According to the fourth aspect of the present invention, since the rubber material is made of an elastic material, the grout material can be prevented from invading between the two by being closely attached to the outer peripheral surface of the screw reinforcing bar. The position of the tip can be confirmed, and the screw depth after construction can be inspected.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a connection device for a screw reinforcing bar according to an embodiment of the present invention.

FIG. 2 is a side view of a joint used in the connection device.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a perspective view of a cap used in the connection device.

FIGS. 5A to 5C are cross-sectional views showing another embodiment of a cap that can be in close contact with a screw rebar.

6A is a cross-sectional view showing a cap with an injection hole, and FIG. 6B is a cross-sectional view taken along line VI-VI in FIG.

FIG. 7 is a cross-sectional view showing another embodiment of a cap with an injection hole.

8 (A) and 8 (B) are explanatory views of a work procedure for connecting a conventional threaded reinforcing bar.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 screw reinforcing bar 1a tip 10 joint 12 inspection hole 13 injection hole 20, 20A to 20E cap 25, 27 injection hole

Claims (4)

[Claims] An apparatus for connecting threaded steel bars by injecting a grout material into the joints in a state where ends of a pair of threaded steel bars are screwed to the joints, wherein the joints are connected to each other. In the central part in the longitudinal direction of the peripheral wall of the peripheral wall, an inspection hole made of a long hole extending in the longitudinal direction is formed for confirming the tips of both the screw rebars, and a grout material is injected away from the inspection hole in the circumferential direction. A coupling device for a screw rebar, comprising an injection hole, and a cap for closing the inspection hole when the grout material is injected into the injection hole. 2. A device for connecting threaded steel bars by injecting a grout material into the joints in a state where ends of a pair of threaded steel bars are screwed to the joints, In the central part in the longitudinal direction of the peripheral wall of the peripheral wall, an inspection hole formed of a long hole extending in the longitudinal direction is formed for confirming the tips of both screw rebars, and a cap for closing the inspection hole when the grout material is injected. And an inlet for injecting a grout material into the cap. 3. The connecting device according to claim 1, wherein the cap is formed of a transparent material. 4. The connecting device according to claim 1, wherein the cap is formed of an elastic material.