JPH06128885A - Terminal fixing tool and terminal fixing method for cable - Google Patents

Abstract

PURPOSE:To obtain a fixing tool having short sleeve length and high fixing ratio by forming a cable-insertion hole at a cable-pressing part of a sleeve and forming a tapped hole at a joint part of a screw shaft to enable the threaded engagement of the screw of the screw shaft. CONSTITUTION:The main body 2 of the sleeve of the tool is composed of a cable-pressing part 5 having a cable-insertion hole 4 and a screw shaft joint part 7 having an outer diameter smaller than the outer diameter of the cable pressing part subjected to diameter-reducing processing. The screw 11 of the screw shaft 10 is threadedly engaged with the tapped hole 6 of the screw shaft joint part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable, particularly a composite cable made of a material having a high strength and a low elongation, for a concrete reinforcing bar (RC) or a prestressed concrete tension bar (P).
The present invention relates to a terminal fixing tool and a terminal fixing method when used as C).

[0002]

2. Description of the Related Art Conventionally, as a fixing device for fixing the end of a PC steel wire using a piano wire, particularly a PC steel stranded wire, there is known one disclosed in Japanese Utility Model Publication No. 52-47844. As shown in FIG. 6, the conventional fixing device 40 has a sleeve portion 41 in which a cable fitting hole 42 for crimping and joining a cable is formed on one side and a tension for engaging a pressure bearing plate on the other side. It has a long rod-like shape including a tension screw portion 43 in which a screw 44 with which a nut is screwed is formed.
For this reason, when the cable is extruded to the fixing tool by shrinking the diameter with a die and pressure bonding is performed, the distance between the die and the piston of the jack is inevitably lengthened and buckling occurs in the fixing tool, resulting in reliable crimping. It is difficult to process. Therefore, conventionally, it has been difficult to apply an extrusion die to the crimping and joining of the crimping tool and the cable, and the crimping and joining of the fixing tool and the cable are performed by using a split die exclusively in two or three times. This is done by successively reducing the diameter of the sleeve.

[0003]

The crimping with a split die is usually divided into a plurality of times in order to receive a shearing load from one direction and to sufficiently reduce the diameter of the sleeve to obtain a fixing efficiency of 100%. Since the wire needs to be pressed, a strong shear load acts on the wire itself. This shearing load is not so problematic in the case of PC steel wire, but a plurality of carbon fibers, aramid fibers, etc., which have been adopted as a tension material in recent years in place of PC steel wire, are gathered, stranded wire processing, and heat curing When applied to a treated composite cable, there is a problem that shearing causes a fold between the press positions and tension causes early rupture.
Further, in the diameter reduction processing by a press, there is a problem in that there is a limit to the crimping force and the sleeve portion must be lengthened in order to obtain a sufficient crimping force, which requires a large space for fixing. . The present invention is intended to solve the problems of the above-described conventional fixing device and fixing method, and even if it is a composite cable made of a high-strength and low-extension material, without applying a strong shear load to the cable itself. An object of the present invention is to provide a fixing device and a fixing method capable of fixing with high fixing efficiency, shortening a sleeve length, and effectively fixing even in a narrow space.

[0004]

In order to solve the above problems, a cable end fixing device according to the present invention has a cable crimping portion in which a cable fitting hole is formed and a diameter smaller than the outer diameter of the cable crimping portion after diameter reduction processing. A sleeve body having an outer diameter of a screw shaft joint portion having a screw hole formed therein; and a screw shaft having a screw screwed into the screw hole of the screw shaft joint portion. It was possible to solve the problem by adopting the configuration. It is desirable to form a protrusion for increasing friction such as spiral cutting on the inner peripheral surface of the cable fitting hole.

Further, in the method of fixing a terminal of a cable using the above-mentioned terminal fixing tool, the terminal fixing part of the cable is inserted into the cable fitting hole of the sleeve body of the terminal fixing tool, and in that state, the cable crimp portion is connected Reduce the diameter with an extrusion die that has a die hole with a minimum inner diameter smaller than the outer diameter, and crimp connect the cable end fixing portion to the cable crimping portion,
The above object is achieved by screwing and connecting a screw shaft to the joint and fixing the other end of the screw shaft to a fixed object. At this time, it is desirable that after the screw shaft is screwed into the joint portion of the terminal fixing tool and connected, a rotation preventing process for preventing relative rotation between the joint portion and the screw shaft is performed. The fixing method is a composite cable made of a high strength and low elongation material, and has a buffer layer integrally formed by impregnating a high strength and low elongation fiber with a thermosetting resin on the outer periphery of the terminal fixing portion. Especially effective for fixing cables.

[0006]

Since the sleeve body and the screw shaft are separately formed, the compression load by the jack can be applied only to the sleeve body by separating the sleeve body and the screw shaft during the crimping process of the composite cable.
Therefore, the portion that receives the compressive load for extrusion can be shortened, and the terminal fixing tool does not buckle even when a strong compressive load is applied, and it is possible to perform diameter reduction processing with a high degree of processing. By activating the jack, the tip of the cable crimping part of the sleeve body is gradually pressed into the die hole by the piston, and while passing through the die hole, the sleeve body is forcibly subjected to plastic working to be reduced in diameter and fitted into the cable fitting hole. Hold the composite cable firmly. At that time, the sleeve body is subjected to uniform strong diameter reduction processing from the entire circumference of its outer circumference, so a much stronger crimping force can be obtained compared to the conventional split die press, and the crimping length can be shortened compared to the past. However, sufficient fixing efficiency can be obtained.

In the case of using an extrusion die, a strong shearing force from one direction is not applied to the outer peripheral portion of the cable, which causes the cable to break early, so it is composed of a stranded wire of high strength and low elongation fiber. Even in the case of a composite cable, sufficient fixing efficiency can be obtained for a long period without damaging the cable. In the case of a composite cable composed of a stranded wire of high strength and low elongation fiber, a cutting edge formed on the inner surface of the cable fitting hole does not directly contact the surface of the composite cable by providing a buffer layer in the fixing part,
There is less risk of damaging the composite cable and higher fixing efficiency is obtained. After screwing the connecting rod, if the connecting rod and part of the connecting rod joint are welded to prevent rotation,
It is possible to prevent the cable from rotating due to torque.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. The terminal fixing tool 1 of the present embodiment is composed of a sleeve body 2 and a screw shaft 10. As shown in FIG. 1, the sleeve main body 2 is provided for screwing a screw shaft with a cable crimping portion 5 in which a cable fitting hole 4 for crimping a sleeve by crimping the cable is fitted. And a screw shaft joint portion 7 in which a screw hole 6 is formed. On the inner surface of the cable fitting hole 4 of the cable crimping portion 5,
As will be described later, a spiral cutting process is performed in order to easily and securely fix the cable to the crimp. Further, the outer diameter of the screw shaft joint portion 7 has an outer diameter slightly smaller than the outer diameter of the cable crimping portion after the diameter reduction processing. Accordingly, when the cable crimping portion 5 is subjected to the diameter reduction processing by the extrusion die, it is possible to prevent the screw shaft joint portion 7 from being subjected to the diameter reduction processing by the extrusion die. In this embodiment, the sleeve main body 2 is manufactured by cutting out from one round bar and integrally forming a cable crimping portion having a different outer diameter and a screw shaft joint portion. The screw shaft 10 has an appropriate length, an external thread 11 is formed on the outer periphery thereof, the base end portion of which can be screwed into the screw hole of the screw shaft joint portion 7, and a tension nut can be attached to the other end portion. It can be screwed.

Next, a description will be given of an embodiment in which a composite cable made of high-strength and low-elongation fiber is fixed by the terminal fixing device of the present embodiment having the above-mentioned structure. In the composite cable 15 in which a plurality of carbon fibers, aramid fibers and the like are collected, twisted and then heat-cured, a buffer layer 16 may be formed in the terminal portion in advance in order to improve fixing efficiency. The buffer layer can be integrally formed by impregnating a high-strength, low-extension fiber with a thermosetting resin and press-molding it around the outer periphery of the terminal fixing portion of the composite cable. The pressure bonding of the composite cable and the terminal fixing device is performed by a pressure bonding device having an extrusion die as shown in FIG. Crimping device 20
Is an extrusion die 21 in which the inner diameter of the minimum portion of the die hole 22 is smaller than the outer diameter of the sleeve body 2 is fixed to the end of the frame 25, and the stroke of the extrusion die is at least the cable crimping portion of the sleeve body 2. A jack 24 having a piston 23 longer than 5 is fixed to the other end.

First, the sleeve body 2 is positioned between the piston 23 and the extrusion die 21 with the die axis and the axis aligned, and in that state, the end portion of the composite cable is inserted into the die hole 22 from the left side in FIG. Then, the terminal portion is fitted and set in the cable fitting hole 4 of the cable crimping portion. Then, when the jack 24 is operated, the sleeve body 2 is gradually pressed by the piston 23 into the die hole, and while passing through the die hole 22, the sleeve body 2 is forcibly subjected to plastic working to be reduced in diameter and fitted into the cable fitting hole. The composite cable 15 that is being held is firmly gripped.

As described above, the end portion of the composite cable is crimp-connected to the sleeve body, and then the screw shaft is screwed into the screw shaft joint portion of the sleeve body.
The fixing process of the cable end is completed by a rotation prevention process for preventing the cable from rotating due to the torque, for example, by partially welding the screw shaft and the screw shaft joint end of the sleeve body. In order to tension and fix the cable thus obtained, as shown in FIG. 5, the screw shaft end is passed through the hole formed in the bearing plate 30 as in the conventional case, and the tension nut after tension is applied. It can be fixed by tightening 26 and bringing it into contact with the bearing plate.

[0012]

The present invention has the following special effects. Since the screw shaft for tension fixing with the sleeve body is formed separately, the part that receives the compressive load for extrusion can be shortened, and the terminal fixing tool will not buckle even under a strong compressive load. It is possible to perform diameter reduction processing with a high degree of processing without causing it. Further, since the screw shaft may be screwed after the sleeve body and the cable end are pressure-bonded to each other, the fixing tool can be easily pressure-bonded by a small extrusion pressure bonding machine even if the screw shaft is long. Since the diameter of the sleeve is reduced by an extrusion die, the sleeve body receives a uniform strong diameter reduction from the entire circumference of its outer circumference, and a much stronger crimping force can be obtained compared to the conventional press with a split die, which makes Even if the pressure bonding length is shortened, sufficient fixing efficiency can be obtained. Further, even in the case of a composite cable composed of a stranded wire of high strength and low elongation fiber, sufficient fixing efficiency can be obtained for a long period without damaging the cable. According to the structure of claim 3, even if a torque is applied to the cable, the screw between the cable and the screw shaft does not loosen, and high tension can be maintained. In the case of a composite cable composed of a stranded wire of high strength and low elongation fiber, a cutting edge formed on the inner surface of the cable fitting hole does not directly contact the surface of the composite cable, especially by providing a buffer layer in the fixing part. There is less risk of damaging the cable and higher fixing efficiency is obtained.

[Brief description of drawings]

FIG. 1 is an exploded front sectional view of a fixing device according to an exemplary embodiment of the present invention.

FIG. 2 is a partial cross-sectional front view showing a crimp connection processing state.

FIG. 3 is a cross-sectional view showing a state in which a fixing tool is pressure-bonded to a cable.

4 is a cross-sectional view taken along the line AA of FIG.

FIG. 5 is a partial cross-sectional front view of the composite cable in a tension-fixed state.

FIG. 6 is a partially sectional front view of a conventional fixing device.

[Explanation of symbols]

1 Terminal Fixing Tool 2 Sleeve Main Body 4 Cable Fitting Hole 5 Cable Crimping Part 6 Screw Hole 7 Screw Shaft Joint 10 Screw Shaft 15 Composite Cable 16 Buffer Layer 20 Crimping Device 21 Piston 22 Extrusion Die

Front page continued (72) Inventor Yoshihiro Abe 7-5-1, Higashi Narashino, Narashino City, Chiba Suzuki Metal Industry Co., Ltd.

Claims (5)

[Claims] 1. A cable crimping portion having a cable fitting hole formed therein, and a screw shaft joint portion having an outer diameter smaller than the outer diameter of the cable crimping portion after the diameter reduction processing and having a screw hole formed therein. A sleeve main body consisting of; and a screw shaft formed with a screw thread that is screwed into the screw hole of the screw shaft joint portion, in combination with the screw terminal fixing device. 2. The cable end fixing device according to claim 1, wherein a protrusion for increasing friction is formed on an inner peripheral surface of the cable fitting hole. 3. The terminal fixing portion of the cable is inserted into the cable fitting hole of the sleeve body of the terminal fixing tool according to claim 1, and in that state, the cable crimping portion of the sleeve body has a minimum inner diameter than an outer diameter of the cable crimping portion. Reduce the diameter with an extrusion die having a small die hole, crimp the cable end fixing part to the cable crimping part, screw the screw shaft to the joint part, and connect the other end of the screw shaft to the fixed object. A method for fixing a terminal of a cable characterized by fixing. 4. The screw shaft is screwed into the joint portion of the terminal fixing device to be connected, and a rotation preventing process is performed to prevent relative rotation between the joint portion and the screw shaft. The cable terminal fixing method according to claim 3. 5. The cable is a composite cable made of a high strength and low elongation material, and has a buffer layer integrally formed on the outer periphery of the terminal fixing portion by impregnating a high strength and low elongation fiber with a thermosetting resin. The method of fixing a terminal of a cable according to claim 3 or 4, wherein: