JPH0718787A - Pc-steel stranded wire connector and connecting method - Google Patents

Abstract

PURPOSE: To abolish a spring for urging a wedge, to facilitate expansion of an inner wall, to facilitate insertion of a PC steel stranded wire, and to eliminate a need for the execution of a preliminary tension work to confirm whether a wedge normally nips the PC stranded wire by previously pressing a wedge in a fit-in part by a screw force. CONSTITUTION: This connection tool comprises a joint 2 for connection to threadedly fix male screw parts 7 and 7 at both sides; right and left chuck bodies 3 and 3 to internally situate a female screw part 11 threadedly engaged with the male screw part 7 and a tapered fit-in part 12; and a divided wedge 4 fitted in a fit-in part 12 and fastening a PC steel stranded wire 5 against an inner wall 13. A chuck body 3 is screwed in the joint 2 for connection as the end face 15 of the wedge 4 is brought into contact therewith.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PC steel stranded wire connecting tool and its connecting method in a prestressed concrete construction method.

[0002]

2. Description of the Related Art As a conventional PC steel stranded wire connector 34, as shown in FIG. 6, male screw portions 36, 36 are provided on both left and right sides.
A pair of left and right chuck bodies 37, 37 are screwed into the connection joint 35 in which is screwed from the left and right, and the wedge 24 divided by the tapered fitting portion 29 is tightened,
PC steel stranded wire 25 inserted from the left and right with its inner wall 30,
Tighten 25. In FIG. 6, the PC steel stranded wire 25 is simply illustrated as a contour line.

Further, the bottom wall 4 of the joint 35 for connection is also provided.
Circular holes 38, 38 are formed on both sides of 0, and springs 39, 39 are mounted in the holes so as to face each other.
4, 24 are urged in the direction of pushing into the tapered fitting portions 29, 29. Thus, the wedges 24, 24 receive the reaction force of the springs 39, 39, and the chuck body 37,
It is tightened by screwing in 37.

However, in the prestressed concrete construction method, the axis C is provided between the PC steel strands 25, 25.
Since tension is applied in the -C direction, the divided wedge 24 is aligned with the tapered fitting portion 29, and the PC steel twisted wire 25 is held in a straight posture to securely grip the wedge 24 as shown in the figure. Need to be done.

[0005]

However, in the PC steel stranded wire connector 34 of the conventional structure, the PC steel stranded wire connector 34 is connected to the PC through the opening 32.
When inserting the steel stranded wire 25, usually one side of the PC
The steel stranded wire 25 has a length of 20 m or more, and it is difficult to insert the steel stranded wire while controlling the steel stranded wire in a straight line. Further, since a large force is required, the spring 39 keeps expanding and contracting unevenly, and the wedge 24 It is possible that the case where the PC steel stranded wire is not urged straightly and the wedge is fastened to the PC steel stranded wire is not necessary.
Inserts the PC steel stranded wire into the taper portion 29 as a unit, and the surface pressure due to the wedge action of the taper portion 29 is not enough to cause slip between the PC steel stranded wire and the wedge inner wall 30. However, there is a problem that confirmation of the sandwiching action cannot be confirmed until a tensile load of about 5 to 15% of the tensile strength of the stranded wire is applied.

In order to detect the above-mentioned inconvenient state and confirm the sandwiching action, it is conventionally obliged to apply pre-tension of the arrow in the direction of the central axis C-C to the PC steel stranded wire 25 after the connection work. , Requires a special hydraulic system,
Since it takes time and labor, work delays and work cost rises.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and eliminates the wedge urging spring, which is a feature of the structure of a conventional connector, to facilitate the expansion of the inner wall. It is easy to insert, and the tightening action that depended on the biasing force of the conventional spring and the pre-tension after connection construction can be tightened directly by screwing in the chuck body, solving the conventional inconvenience factor However, the process of pre-tensioning, which is a factor of work delay and cost increase, becomes unnecessary.

That is, according to the structure of the present invention, (1) the gripping portion 6 for screwing is provided at the center of the outer periphery of the member, and the male screw portions 7, 7 are screwed on both right and left sides thereof, and the axis (C- A connecting joint 2 formed by forming circular holes 9 and 9 facing each other with the bottom wall 8 sandwiched in the C direction, and a screwing grip portion 1 at the rear end of the outer circumference of the cylindrical body.
A pair of left and right chuck bodies 3, 3 each having a female threaded portion 11 internally threaded with the male threaded portion 7 and a tapered fitting portion 12 formed at the rear end thereof.
And a split wedge 4 which is fitted into the fitting portion 12 and grips the PC steel stranded wire 5 by the inner wall 13 thereof, and a PC steel stranded wire connector 1 and (2)
In the PC steel twisted wire connector 1, first, the chuck body 3 is loosened to separate the joint 2 for connection and the wedge 4, the PC steel twisted wire 5 is inserted from the opening 17, and the wedge 4 is connected. 2 is abutted against the inner wall 13 to expand the crack 20 and is inserted through the inner wall 13 so that the tip 18 is attached to the bottom wall 8.
The PC steel stranded wire 5 is corrected to a straight posture by the bottom wall 8, then the chuck body 3 is tightened, the wedge 4 is pushed into the fitting portion 12, and the PC steel stranded wire 5 is tightened by the inner wall 13. This is a method of connecting the PC steel twisted wire 5 characterized in that

In the above-mentioned connecting tool, it is preferable that the screwing gripping portion 10 on the outer periphery of the cylindrical body has a polygonal shape such as a quadrangle, a hexagon, an octagon, and the like. It is also preferable that the end surface 15 of the wedge 4 is brought into contact with the chuck body 3 so that the chuck body 3 can be screwed. Further, it is also preferable to form a saw-toothed groove 16 that serves as a resistance in the drawing direction D with respect to the PC steel strand 5 on the inner wall 13 of the wedge 4.

[0010]

EXAMPLES Examples of the present invention will be described in detail below. FIG. 1 is a front sectional view of a PC steel twisted wire connector of the present invention showing a state where PC steel twisted wires are connected, and FIG. 2 is AA of FIG.
FIG. 3 is a central sectional view taken along the line, and FIG. 3 is a side sectional view taken along the line BB in FIG.

The PC steel twisted wire connector 1 of the present invention comprises a connecting joint 2 in the center, chuck bodies 3 and 3 screwed to the left and right sides thereof, and a pair of left and right tightened by opposed tapered fitting portions 12 and 12. And the divided wedges 4, 4, and the left and right PC steel stranded wires 5, 5 are fastened and connected by the inner walls 13, 13.

The connecting joint 2 is provided with a quadrangular or hexagonal gripping portion 6 at the center of the outer periphery of the member so that it can be easily screwed with a spanner or the like. The circular grip portion 6 may be knurled and screwed with a pipe wrench. Further, male screw portions 7 and 7 are screwed on the right and left sides of the grip portion 6, and the male screw portions 7 and 7 are machined so as to face each other left and right. Further, circular holes 9, 9 are formed on the left and right sides of the bottom wall 8 in the axial direction CC of the member center. Further, since the end face 14 of the connecting joint 2 is brought into contact with the end face 15 of the wedge 4 and tightened, it is desirable that both end faces are flat and the inner diameter of the circular hole 9 is smaller than the outer diameter of the end face 14, while the PC steel stranded wire is used. Since 5 is inserted, it is desirable that it is larger than its outer diameter. A small-diameter air hole is formed in the bottom wall 8.

The chuck body 3 is provided with a quadrangular or hexagonal gripping portion 6 at the rear end of the outer periphery of its cylindrical body so that it can be easily screwed with a spanner or the like. The circular portion may be knurled and screwed with a pipe wrench. Further, a female screw portion 11 which is screwed with the male screw portion 7 of the connecting joint 2 is internally provided at the tip of the inner periphery in the center direction, and can be screwed to the left and right of the connecting joint 2. At the rear end of the inner circumference thereof, a fitting portion 12 is formed which is expanded in a tapered shape from the opening 17 of the rear end surface. The inner diameter of the opening 17 is slightly larger than the outer diameter of the PC steel strand 5.

FIG. 4 is an exploded development view of the wedge 4, in which 4-1 is divided into three parts and 4-2 is divided into two parts. Three divisions are preferable to two divisions. Further, FIG. 5 is a partial cross-sectional view for explaining the saw-tooth groove 16 of the inner wall 13. The tapered wedge 4 divided into three or two at the split 20 is fitted into the fitting portion 12 of the chuck body 3. A circular hole smaller than the PC steel twisted wire 5 is penetrated through the center of the wedge 4, and the PC steel twisted wire 5 is fastened by the inner wall 13 divided into three or two when fitting. Further, the inner wall 13 is formed with saw-tooth grooves 16 so as to resist the PC steel strand 5 in the drawing direction D. A rectangular circumferential groove 19 is provided on the outer circumference of the wedge 4, and the circumferential groove 19 is
A wire 33 is wound around the wire to help integrate the wedge 4.

Next, a method of connecting the PC steel twisted wire 5 by the PC steel twisted wire connector 1 constructed as described above will be described. First, the left and right chuck bodies 3, 3 screwed to the connecting joint 2 are loosened, and the end surface 1 of the connecting joint 2 is loosened.
4 and the end surface 15 of the wedge 4 are separated from each other.

Insert the PC steel stranded wire 5 through the opening 17,
The end surface 15 of the wedge 4 is the end surface 14 of the connecting joint 2.
The wedge 4 is pushed in by its tip 18 until it abuts against.
The divided wedges 4 are integrally moved by the wires 33, released from the fitted state in the fitting portion 12, and the inner wall 13 can be expanded at the crack 20.

The PC steel stranded wire 5 can be inserted through the inner wall 13, and the tip 18 thereof passes through the inner wall 13 and abuts on the bottom wall 8. The PC steel strand 5 is corrected to a straight posture by the bottom wall 8.

Next, the chuck body 3 is screwed into the connecting joint 2 and tightened by using the grip portion 6 and the grip portion 10. The wedge 4 is fitted into the fitting portion 12 again, the divided inner wall 13 is contracted and closed, the PC steel stranded wire 5 is fastened, and the connection is completed. In the tightened state, a slight tightening margin is left between the male screw portion 7 and the female screw portion 11. The left and right sides may be connected separately, or the left and right sides may be connected simultaneously.

[0019]

Since the present invention has the above-mentioned constitution and operation, it can exert the following various effects. First, since direct screw-in tightening is sufficient, connection work is simple and the tightened state can be easily confirmed. Further, since the conventional construction of preliminary tension is unnecessary, inconveniences such as work delay and cost increase can be eliminated. And this PC steel stranded wire connector is
Since there is no spring bias, it is easy to insert PC steel strands.

[Brief description of drawings]

FIG. 1 is a front sectional view of a PC steel twisted wire connector according to an embodiment of the present invention.

FIG. 2 is a central sectional view taken along the line AA of FIG.

FIG. 3 is a side sectional view taken along line BB of FIG.

FIG. 4 is an exploded development view of the divided wedge,
4-1 is divided into 3 parts, 4-2 is divided into 2 parts

FIG. 5 is a partial cross-sectional view of an inner wall of a wedge in which a saw tooth groove is formed.

FIG. 6 is a front sectional view of a conventional PC steel stranded wire connector.

[Explanation of Codes] 1 PC steel twisted wire connector 2 Joint for connection 3 Chuck body 4 Wedge 5 PC steel twisted wire 6 Gripping part 7 Male screw part 8 Bottom wall 9 Circular hole 10 Gripping part 11 Female screw part 12 Fitting part 13 Inner wall 14 End surface 15 End surface 17 Opening 18 Tip 19 Circumferential groove 33 Wire 34 Conventional PC steel stranded wire connector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 000183325 Sumitomo Construction Co., Ltd. 13-13 Araki-cho, Shinjuku-ku, Tokyo (72) Inventor Keiji Yamagata 10-1 1 Hiraoka, Toyohira-ku, Sapporo Housing No. 134 (72) Inventor Isoji Kojima, Sumikawa Minami-ku, Sapporo-shi 2-2-2-16 Road Public Corporation Housing No. 101 (72) Inventor Yoshitaka Nishida 4-12 Takaha-cho, Nada-ku, Kobe

Claims (6)

[Claims] 1. A gripping portion (6) for screwing is provided at the center of the outer periphery of the member, and male screw portions (7, 7) are screwed on both left and right sides of the gripping portion (6), and a bottom wall (8) is formed in the central axis (CC) direction. The connecting joint 2 is formed by forming circular holes 9 and 9 facing each other, and a screwing gripping portion 10 is provided at the rear end of the outer circumference of the cylindrical body. A pair of left and right chuck bodies 3, 3 each having a female thread portion 11 to be fitted therein and a tapered fitting portion 12 formed at the rear end thereof, and fitted into the fitting portion 12;
A PC steel stranded wire connector 1 comprising a divided wedge 4 which grips a PC steel stranded wire 5 on its inner wall 13. 2. The PC steel twisted-wire connector 1 according to claim 1, wherein the threaded gripping portion 10 on the outer circumference of the cylindrical body has a polygonal shape. 3. The PC according to claim 1, wherein the chuck body 3 can be screwed by bringing the end surface 15 of the wedge 4 into contact with the end surface 14 of the connecting joint 2.
Steel stranded wire connector 1. 4. The inner wall 13 of the wedge 4 is provided with a saw-toothed groove 16 that acts as a resistance against the PC steel strand 5 in the drawing direction D, according to any one of claims 1 to 3. PC steel stranded wire connector 1. 5. A rectangular circumferential groove 19 is provided on the outer periphery of the divided wedge 4, and a wire 33 is wound around the circumferential groove 19 so that the cracks 20 do not shift. The PC steel stranded wire connector 1 according to any one of claims 1 to 4. 6. P according to any one of claims 1 to 5.
In the C steel stranded wire connection tool 1, first, the chuck body 3 is loosened to separate the connection joint 2 and the wedge 4,
The PC steel stranded wire 5 is inserted through the opening 17, the wedge 4 is brought into contact with the connecting joint 2, and the crack 20 in the inner wall 13 is inserted.
The inner wall 13 and the tip 18 abuts against the bottom wall 8. The bottom wall 8 corrects the PC steel stranded wire 5 to a straight posture, and then the chuck body 3 is tightened to close the wedge 4. The method for connecting the PC steel twisted wire 5 is characterized in that the PC steel twisted wire 5 is pressed into the fitting portion 12 and the PC steel twisted wire 5 is fastened by the inner wall 13.