JP2000170324A - Connection device for screw rebar - Google Patents

Abstract

(57) [Problem] To provide a connecting device capable of minimizing the distance between screw rebars. SOLUTION: A coupling device J1 includes a pair of joints 10, and a pair of half bodies 20 bridged between the joints 10, and a first locking projection 23 of the half body 20 is provided on the joint 10. By hitting the second locking projection 12, the pair of joints 10 is prohibited from moving in a direction away from each other. Fitting 1
In 0, a screw hole 11 for screwing the screw reinforcing bar 2 is formed over the entire length.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for connecting a pair of rebars arranged in a straight line.

[0002]

2. Description of the Related Art Generally, a tubular coupler nut is used to connect a pair of threaded reinforcing bars. With this coupler nut screwed onto one of the threaded rebars, and with the threaded rebars arranged in a straight line with the same pitch, turn the coupler nut and apply about half the length to the other threaded rebar. Just screw them together. However, for example, when a pair of screw reinforcing bars are used as main reinforcing bars of separate precast concrete structures, it is difficult to match the pitches of these screw reinforcing bars, so the above connection method cannot be adopted. .

[0003] Japanese Patent Application Laid-Open No. 10-26 discloses an example of a structure which can be connected even if the pitches of the screw reinforcing bars do not match.
There is a connecting device disclosed in Japanese Patent No. 6466. This coupling device includes a pair of joints facing each other in an axial direction and a pair of half bodies facing each other in a radial direction. A pair of first locking projections separated in the axial direction are formed on the inner periphery of each half. A second locking projection is formed on the outer periphery of one end of each joint, and a screw hole for screwing a screw rebar is formed on the other end.

[0004] A pair of joints are screwed to separate threaded bars. Then, the pair of joints is bridged between the pair of joints such that the second locking protrusions of the pair of joints are arranged between the pair of first locking protrusions of each half. . In this state, the screwing depth of the joint to the threaded rebar is adjusted so that the first locking projection and the second locking projection abut. This allows
The pair of threaded reinforcing bars are connected regardless of the pitch mismatch.

[0005]

The connecting device disclosed in the above publication has a problem that the distance between the pair of threaded reinforcing bars is too large. That is, in the joint, the second locking projection and the screw hole are disposed at one end and the other end along the axial direction, respectively, so that one end of the joint is projected from the end of the screw rebar. Become. Therefore, the ends of the pair of threaded rebars must be separated by at least the combined length of the protruding end of at least one joint and the protruding end of the other joint.

[0006] In the precast concrete structure, the screw rebar projects from the end face of the precast concrete. Therefore, when the distance between the pair of screw reinforcing bars increases, the distance between the precast concrete of the pair of structures also increases. For this reason, the amount of post-cast concrete in the space between these precast concretes after the connection of the screw rebar increases.

[0007]

In order to solve the above-mentioned problems, a first aspect of the present invention has a pair of joints having a screw hole, and having a threaded rebar screwed into the screw hole and facing in the axial direction in a state of being screwed. ,
A pair of half halves that are bridged between the pair of joints and that face each other in the radial direction, and a pair of arc-shaped first locking projections that are separated in the axial direction on the inner periphery of each half. Is formed, and an annular second locking projection is formed on the outer periphery of each joint, and the second locking projection of the pair of joints is disposed between the pair of first locking projections. A first locking projection and a second locking projection that prevent a pair of joints from moving in a direction away from each other in the axial direction; Is formed over the entire length of the screw hole, whereby the second locking projection is positioned radially outward of the screw hole.

According to a second aspect, in the first aspect, the first locking projections are formed at both axial ends of the half body, and the second locking projections are formed at opposite ends of the pair of joints. Is formed.

According to a third aspect of the present invention, in the first or second aspect, connecting portions projecting in the radial direction are formed at both circumferential ends of each half, and the connecting portions of the pair of half are opposed to each other. In this state, the halves are connected to each other by a bolt penetrating the facing connecting portion and a nut screwed to the bolt.

According to a fourth aspect of the present invention, in the first or the second aspect, the pair of first locking projections of each half body have radially inner ends protruding in a direction approaching each other in the axial direction. A first sub-projection is formed, and an annular second sub-projection is formed at a radially outer end of the second locking projection of the pair of joints so as to project in a direction away from each other in the axial direction. It is characterized in that the half-split bodies are connected via a joint by the engagement of the first sub-projection and the second sub-projection.

A fifth invention is characterized in that, in any one of the first to fourth inventions, a grout inlet is formed in one of the pair of half bodies.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, a connecting device J1 according to the first embodiment of the present invention is used for connecting the ends of a pair of screw rebars 2. The pair of threaded reinforcing bars 2 constitute main reinforcing bars of the precast concrete structure 1 that are separate from each other. The end of the screw reinforcing bar 2 protrudes from the end surface of the precast concrete 3 of the structure 1.

The connecting device J1 is provided with a pair of joints 10 opposing each other in the axial direction of the screw reinforcing bar 2 and a pair of half bodies 20 opposing each other in the radial direction. The joint 10 has a screw hole 11 for screwing the screw reinforcing bar 2 and has a cylindrical shape. The screw hole 11 extends over the entire length of the joint 10. Annular second locking projections 12 are formed at opposite ends of the outer periphery of the pair of joints 10, respectively. That is, the second locking projection 12 is provided radially outward of the screw hole 11.
Is located.

As shown in FIG. 2, the half body 20 is composed of a main body 21 having a semi-cylindrical shape (circular arc shape in cross section), and a pair of radially projecting and provided at both circumferential ends of the main body 21. And the connecting portion 22 of As shown in FIG. 1, a pair of arc-shaped first locking projections 23 are formed at both axial ends of the inner periphery of the main body 21. A grout inlet 21 a is formed in the center of the main body 21 in one half 20. Each connecting part 22 has a through hole 2
2a is formed.

A procedure for connecting the pair of screw rebars 2 by the connecting device J1 configured as described above will be described. A pair of joints 10 are previously screwed to the ends of the separate screw rebars 2. At this time, it is preferable to screw the joint 10 until the threaded reinforcing bar 2 penetrates the joint 10. Then, a pair of precast concrete structures 1
The screw rebars 2 are made to face each other so that they are aligned. Thereby, the pair of joints 10 oppose each other in the axial direction of the screw reinforcing bar 2. Note that it is not necessary to match the pitch between the screw rebars 2.

Then, the joints 10 are turned in a direction approaching each other, and the distance between the opposite surfaces of the second locking projections 12 of the pair of joints 10 opposite to the opposing surfaces is equal to the pair of first
It is made smaller than the distance between the opposing surfaces of the locking projections 23. Next, a pair of first locking projections 2 of one half body 20 are formed.
The half body 20 is bridged between the pair of joints 10 so as to accommodate the second locking projections 12 of the pair of joints 10 between the three joints 10. Also, the other half body 20 is replaced with the one half body 20.
While being radially opposed to each other. Thereafter, the joints 10 are turned in a direction away from each other. Eventually, the second locking projection 12 becomes the first locking projection 2.
In the case of 3, it is forbidden that the pair of joints 10 move further in the axial direction. Therefore, the connecting device J1 can bear the tensile stress. The distance between the second locking projections 12 of the pair of joints 10 is adjusted to the distance between the pair of first locking projections 23 of the half body 20, and then the half body 2
0 may be bridged between the joints 10.

The connecting portions 22 abut against each other in a state in which the pair of half bodies 20 face each other in the radial direction, and the through holes 22a of the connecting portions 22 are aligned with each other. This matched through hole 22a
Then, a nut 31 is screwed into the bolt 30 and tightened to connect and fix the halves 20 together. Thereby, the connection state of the pair of joints 10 is ensured.

Thereafter, grout is injected from the grout injection port 21a. The grout is filled in the gap between the pair of joints 10 and also in the gap between the inner circumference of the screw hole 11 and the outer circumference of the screw reinforcing bar 2. by this,
The connection strength between the joint 10 and the screw reinforcing bar 2 can be maintained.

In the connecting device J1 having the above structure, the screw holes 11
Are formed over the entire length of the joint 10, whereby the second
Since the locking projection 12 is located radially outward of the screw hole 11, the length of the joint 10 protruding from the end of the screw rebar 2 is extremely short, or the joint 10 has
The threaded reinforcing bars 2 can be connected to each other in a state where the threaded steel bars 2 are penetrated. Therefore, the distance between the ends of the pair of threaded reinforcing bars 2 can be minimized, and thus the distance between the end faces of the pair of precast concretes 3 can be minimized. As a result, it is possible to minimize the amount of post-cast concrete between the precast concretes 3 after the connection of the screw reinforcing bars 2.

Next, a second embodiment of the present invention will be described with reference to FIGS. In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description is simplified. The half body 10 of the connecting device J2 according to this embodiment is different from the connecting portion 22 in the device J1.
Do not have. Instead, a pair of first locking projections 2
An arc-shaped first sub-projection 24 that protrudes in a direction approaching the axial direction is formed at the radially inner end of No. 3. Further, in the pair of joints 10, radially outer ends of the second locking projections 12 are provided with annular second projections projecting in a direction away from each other in the axial direction.
The sub convex portion 13 is formed.

As shown in FIG. 3, when connecting the threaded reinforcing bar 2 with the connecting device J2, the distance between the tips of the second sub-projections 13 of the pair of joints 10 screwed to the threaded reinforcing bar 2 is reduced. The distance between the tips of the pair of first sub-projections 24 of the half body 20 is made smaller. Then, the second locking projection 12 and the second sub-projection 13 of the joint 10 are inserted between the first locking projection 23 and the first sub-projection 24 of the half body 20 so that the half The body 20 is bridged between the joints 10.

Then, the joint 10 is turned in a direction away from each other, and the second sub-projection 13 of the joint 10 abuts against the first locking projection 23 of the half body 20 as shown in FIG. The stop projection 12 is brought into contact with the first sub-projection 24. In this state, the second sub-projection 13 of the joint 10 is located radially outside of the first sub-projection 24 of the half body 20 and prevents the half body 20 from moving in the radially outward direction. Thereby, a pair of half bodies 2
0 is connected via the joint 10.

The present invention is not limited to the above-described embodiment, but can adopt various forms. For example, instead of or in addition to grouting, a lock nut is screwed onto the precast concrete 3 side from the joint 10 in the threaded reinforcing bar 2, and the lock nut is abutted against the joint 10, so that the joint 10 is connected to the joint 10. The connection strength of the screw reinforcement 2 may be maintained. The connection device of the present invention can also be applied to connection of a screw rebar incorporated as a main rebar in a rebar cage.

[0024]

As described above, in the first invention,
Since the threaded hole is formed over the entire length of the joint, the length of the joint protruding from the end of the threaded bar can be minimized, and the distance between the ends of the pair of threaded bars can be minimized. . Therefore, when used for connecting precast concrete structures, the distance between the end faces of the pair of precast concrete can be minimized, and the amount of post-cast concrete between the precast concrete can be minimized.

According to the second aspect, the axial length of the connecting device can be reduced. According to the third invention, the pair of halves can be easily fixed with the bolts and the nuts while keeping the distance between the screw rebars short. According to the fourth aspect, the pair of halves can be connected via the joint without using special fixing means such as bolts and nuts. In the fifth invention, grout is filled into the gap between the pair of joints from the grout inlet,
Further, the gap between the inner periphery of the screw hole and the outer periphery of the screw reinforcing bar can be filled. Thereby, the connection strength between the joint and the screw rebar can be maintained.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line XX of FIG.

FIG. 3 is a side cross-sectional view showing a second embodiment of the present invention in a state before a pair of half bodies are connected via a joint.

FIG. 4 is a side sectional view showing a state after connection of the half bodies in FIG. 3;

[Explanation of symbols]

 J1, J2 Connecting device 2 Screw bar 10 Joint 11 Screw hole 12 Second locking convex portion 13 Second sub convex portion 20 Half body 22 Connecting portion 21a Grout inlet 23 First locking convex portion 24 First sub convex portion 30 bolt 31 nut

Claims (5)

[Claims] 1. A pair of joints having a screw hole and having a threaded rebar screwed into the screw hole and facing in the axial direction, and being spanned between the pair of joints and radially facing each other. A pair of halves, and a pair of arc-shaped first halves separated in the axial direction are provided on the inner periphery of each half.
A locking projection is formed, and an annular second locking projection is formed on the outer periphery of each joint. The second locking projection of the pair of joints is disposed between the pair of first locking projections. In the connecting device for a screw rebar, in which the pair of joints is prevented from moving in a direction away from the axial direction by the first locking projection and the second locking projection abutting on each other, A coupling device for a screw reinforcing bar, characterized in that a hole is formed over the entire length of the joint, whereby the second locking projection is located radially outward of the screw hole. 2. A method according to claim 1, wherein the first locking projections are formed at both ends in the axial direction of the half body, and the second locking projections are formed at opposite ends of the pair of joints. The connecting device for a screw reinforcing bar according to claim 1. 3. A connecting portion projecting in the radial direction at both ends in the circumferential direction of each half body, and a bolt penetrating the opposed connecting part with the connecting parts of the pair of half bodies facing each other. The connecting device for a screw reinforcing bar according to claim 1 or 2, wherein the halves are connected to each other by a nut screwed to the bolt. 4. An arc-shaped first sub-projection projecting in a direction approaching the axial direction is formed at a radially inner end of a pair of first locking projections of each half body. At the radially outer ends of the second locking projections, there are formed annular second sub-projections projecting in directions away from each other in the axial direction, and the engagement between the first sub-projections and the second sub-projections. The connecting device for a screw reinforcing bar according to claim 1 or 2, wherein the halves are connected to each other via a joint. 5. The connection device according to claim 1, wherein a grout inlet is formed in one of the pair of half bodies.