JPH0458126B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a cable having at least two helically wound tapes, such as a shielded control cable;
The present invention relates to improvements in cable twisting methods for manufacturing twisted wire cables such as compensation conductors.

When manufacturing this type of cable, multiple core wires are collected in a twisting die and twisted together through a rotary take-up machine and a rotary take-up machine.A taping machine is placed between the twist die and the take-up machine. The tape is then wrapped around the strands. However, if the cable is small in diameter, the stranded wire is subject to the tension of the tape during tape winding, so the twist in the rotary pulling machine is not properly transmitted to the twisting die, resulting in uneven twist pitch. There was a drawback that the wrapped tape could stretch or break.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cable twisting method that can properly maintain the twist pitch of the cable strands and prevent the tape from stretching and breaking.

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows the method of the present invention, in which a plurality of insulated core wires 1 are collected by a twisted rod die 10 and passed through a rotary take-off machine 12. The cables 3 are twisted together and wound up as a cable 3 by a rotary winder 14. A plurality of insulated core wires 1 are twisted by a twisting rod die 10 and a rotary pulling machine 1.
A plurality of taping machines 16, 18, 20 wrap tapes 4, 5, 6 onto the strands 2 formed by twisting the strands 2 and 2 together.

In this method, when the twisting direction of the stranded wire 2 is, for example, S twist as shown in FIG. 2, the winding direction of the tapes 4, 5, and 6 is generally as shown in FIG. That is, the winding direction of the tape 4 is to the left when viewed from the front side (supply side) in the traveling direction of the stranded wire 2, and the winding direction of the tapes 5 and 6 is to the right and left, respectively. If cable 3 is a shielded control cable, tapes 4 and 6 are each a non-woven tape, while tape 5 is a shielding tape, such as a copper tape. Due to the bending characteristics of the cable, a relatively small width tape is used for the shielding tape, so in order to eliminate gaps between the tapes, the pitch must be small, and the number of rotations of the taping machine is higher than with other tapes, which increases the tension of the tape. difficult to control. On the other hand, since the tape 5 is rotated in the opposite direction to the rotating direction of the rotary take-off machine 12, especially when the tension of the tape is excessive, the stranded wire 2 will be twisted in the same direction as its twisting direction. There is a tendency for there to be insufficient twisting between the taping machine 10 and the taping machine 18, and on the contrary, there is a tendency for excessive twisting between the taping machine 18 and the rotary take-off machine 12. On the other hand, taping machine 18
Since the tape 5 is wound to the right around the stranded wire 2 between the wire and the rotary take-off machine 12, if the twist is excessive in the right direction, the tape 5 may become tight, stretch, and even break. Meanwhile, tapes 4 and 6 will become loose.

The present invention has been made to solve the above-mentioned problems, and one embodiment of the present invention will be described with reference to the drawings. Rotation assisting means 22, 22', which rotate in synchronization with the rotary take-off machine 12, are arranged before and after the part to be wound on the stranded wire 2, so that the stranded wire 2 is connected to the rotary take-off machine 12 as shown by arrow a in FIG. Apply rotational force in the same direction. In this way, the twisted wires 2 are twisted in the same way before and after the taping machine 18, thereby preventing the twist pitch from being disordered, and also preventing the tape 5 from stretching or breaking. still,
This rotation assisting means 22, 22' is the rotary take-up machine 12
It only needs to rotate in synchronization with the motor, and no pulling force is required.
Further, it is preferable that the rotation assisting means 22, 22' be in the form of a belt or a capstan so that the portion in contact with the stranded wire 2 is not a point but a plane. Furthermore, one of the rotation assisting means 22 and 22' may be omitted.

According to the present invention, as described above, the twist pitch of the stranded wires is uniform over the entire length, and the tape is prevented from stretching and breaking when wound in the opposite direction to the rotational direction of the rotary take-up machine. Moreover, since it is only necessary to add a simple rotation assisting means, the equipment does not become complicated.

[Brief explanation of drawings]

FIG. 1 is a schematic system diagram for explaining the method of the present invention, and FIG. 2 is an explanatory diagram for explaining the state in which the twist pitch of the stranded wire is made uniform by the method of the present invention. 1...Insulated core wire, 2...Twisted wire, 3...Cable, 4, 5, 6...Tape, 10...Twisting rod dies, 12...Rotary winding machine, 14...Rotary winding machine.

Claims (1)

[Claims] 1 A plurality of core wires are collected through a twisting die, twisted together using a rotary take-up machine, and wound onto a rotary take-up machine, and between the twisting die and the rotary take-up machine, at least two In a cable twisting method in which two tapes are spirally wound in mutually opposite directions, the stranded wire is attached to the stranded wire at least either before or after a portion where the tape is spirally wound on the stranded wire in a direction opposite to the rotational direction of the rotary pulling machine. A method for twisting cables, characterized in that rotational force is applied by a rotational auxiliary means that rotates synchronously in the same direction as the rotary pulling machine.