JPS6257044B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method for manufacturing SZ stranded communication cables.

As a method for manufacturing an SZ twisted communication cable, there is a method in which a plurality of units are individually SZ twisted and then collectively twisted. In this case, in order to prevent the SZ twist of each unit from untwisting and to differentiate by color,
After SZ twisting, each unit is wrapped with colored tape or the like for restraint. However, if a restraining winding is wound between the SZ twisting head that performs SZ twisting and the collective twisting head, it is necessary to increase the distance between the two heads.
In addition, untwisting is likely to occur when the reversed part of the SZ twist passes, and the mechanism is complicated because a restraining winder is interposed in the part where the units are gathered in a tapered shape between the SZ twisting head and the collective twisting head. There was a drawback.

The object of the present invention is to shorten the distance between the SZ twisting head and the collective twisting head so that the distance between them can be reduced.
An object of the present invention is to provide a method for manufacturing an SZ twisted communication cable that can prevent untwisting of an SZ twisted unit and simplify the machine.

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows a method for manufacturing an SZ stranded communication cable according to the present invention, in which a plurality of parallel assembly units 10 each form a pair or a joint in parallel. This parallel gathering unit 10 is formed by wrapping a restraining winding using a colored tape in a restraining winding machine 12, and then winding it in a restraining winding machine 12, and then winding it in an SZ twisting head 14 of an SZ twisting machine.
The cables are SZ-twisted to form an SZ-twisting unit 10', and then collectively twisted by a collecting head 16 and wound onto a winding drum 20 as an SZ-twisted communication cable 18. If the restraining winder 12 is located upstream of the SZ twisting head 14 in this way, the distance between the SZ twisting head 14 and the collective twisting head 16 can be shortened, so that the inverted part of the SZ twist can be formed between them. Since the existence time is short and there is a restraining winding wound in advance, untwisting of the SZ twist is extremely reduced.

In the twisting head 14 of the SZ twisting machine, each unit 10
are twisted as shown in FIG. Each SZ twisting head 14 has two rotating supports 24, 24', each consisting of a pair of rollers, located inside two fixed supports each consisting of a pair of rollers. Each unit 10 is connected to these fulcrums 22, 24, 2
4' and 22' at a constant speed v ₀ , and the rotating fulcrum 2
Rotating fulcrum 2 for every distance 1 between 4 and 24'
4 and 24' are alternately rotated in forward and reverse directions about the axis of the unit 10 to perform SZ twisting. In this case, the rotational supports 24, 24' are initially set n ₁ in the same direction as the winding direction of the restraining winding on the unit 10, as shown in FIG. 2A.
_The unit 10 rotates at a rotational speed _of The rotation speed is _n1 . In this way, the unit 10 is moved between the rotation supports 24 and 24'.
They are twisted alternately with a twist pitch of P ₁ =v ₀ /n ₁ , P ₂ =v ₀ /n ₁ −n ₂ (>P ₁ ), that is, SZ twist. Therefore, since the twist in the loosening direction of the restraining winding is particularly small, the winding loosening of the restraining winding is also small, and since SZ twisting is performed, the effects of SZ twisting, such as preventing crosstalk between units, can be maintained. It is preferable that the twist pitch of the S twist and the Z twist be approximately 2:1. Furthermore, the second
In the figure, the rotational speed of the rotational supports 24, 24' is
n ₁ and n ₂ may be reversed. In addition, the fixed fulcrum 22,
Distances S ₁ , S ₂ between 22' and rotational supports 24, 24'
is set to be sufficiently shorter than distance 1.

According to the present invention, as described above, the restraining winding is
Since it is wrapped before SZ twisting, the distance between the SZ twisting head and the collective twisting head can be made as short as possible, which has the practical benefit of effectively preventing the SZ twisting of each unit from untwisting.

[Brief explanation of the drawing]

FIG. 1 is a schematic system diagram of the method for manufacturing SZ stranded wire according to the present invention, and FIG. 2 is an explanatory diagram illustrating the inside of the twisting head. 10...Parallel collecting unit, 12...Tight winding machine, 14...Twisting head of SZ twisting machine, 16...
Collective twisting head, 24, 24'...rotation fulcrum.

Claims (1)

[Claims] 1. An SZ-twisted communication cable characterized in that after each of a plurality of parallel set units is wound with a restraining winding, each parallel set unit is SZ-twisted, and then the plurality of SZ-twisted units are collectively twisted. manufacturing method. 2. According to claim 1, the twist pitch between the S twist and the Z twist of each SZ twist unit is changed so that the twist pitch becomes larger in the direction of loosening of the restraining winding on each of the units. SZ listed
Method for manufacturing twisted communication cables. 3. The method of manufacturing an SZ twisted communication cable according to claim 2, wherein the twist pitch is changed by changing the rotational speed of the rotational fulcrum of each unit in the forward direction and the reverse direction.