JPS6355729B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method of manufacturing a communication cable, and more particularly, to a method of manufacturing a tandem assembly type communication cable for improving crosstalk characteristics. Conventionally, when manufacturing a communication cable called a so-called local cable, for example, as shown in Fig. 1, a plurality of twisted wire cores Q (in the case of cut wires, there are usually five wires) are used.
are sent out from the delivery bobbins 11, 12, . The tape is twisted by applying a twisting force, and the tape is loosely wound 3. Then, a plurality of these subunits S are gathered together in a collection cap 5 to form a unit U, and the tape is roughly wound 6 and collectively twisted by a take-up device 7, and then the tape is twisted by a take-up device 7. It is wrapped around 8. This is a so-called tandem manufacturing method in which the steps from feeding out the stranded wire core to winding the wire into units are carried out in a series. Although this tandem manufacturing method is an efficient manufacturing method in that each process is performed in series, the direction of this twist in the oscillating twist when twisting the subunit S is the twist of the stranded wire core such as a cut. When the direction is reversed, there is a disadvantage that the twisted wire core is untwisted and the cup arrangement is disrupted.Also, in unit collective twisting, either the S or Z twist of each subunit S is untwisted (as shown in Figure 1). In the example, since the unit aggregate twist is Z twist, the S twist portion of the subunit S is untwisted.) There is a drawback that the aggregate pitch of the subunit S becomes irregular. These drawbacks, however, reduce the effectiveness of the measure to make the twist pitches of each couple slightly different from each other when the subunits S are assembled, and create a new drawback of degrading the crosstalk characteristics in the unit cable. The present invention has been made to eliminate such drawbacks, and provides a novel communication cable manufacturing method that provides SZ twists with different pitches to each subunit to be assembled into a unit. , and as shown in Figures 2 and 3 below.
An embodiment of the invention will be described with reference to the drawings. In Fig. 2, reference numerals 11, 12, . The subunits S are grouped together in the cap 4 and directed to the unit collection cap 5. The present invention is characterized in that an SZ twisting device 9 is provided for each subunit S immediately upstream of the unit collecting cap 5, thereby imparting SZ twist to each subunit S. As shown in FIG. 3, this SZ twisting device 9 has sheave groups 92 and 93 arranged opposite each other in which a plurality of sheaves are rotatably arranged in parallel on a frame 91, and has a hollow inlet shaft. By rotating frame 91 about 94 and exit axis 95, torsion can be imparted to subunit S. Now, let the accumulation length of this sheave group be l, the traveling speed of the subunit S be v, the number of rotations of the frame 91 be N times per hour, and the rotating direction of the frame 91 is such that the subunit S is The time T to pass through the accumulation length l, that is,
It is assumed that forward and reverse inversion is performed every T=l/v. In this way, the subunit S passing through the SZ twisting device 9 becomes an SZ twisted wire in which the S twist and the Z twist of the twist pitch v/2N appear alternately for every length l, and in this twisted state, the collective nozzle is The tape is wound by a rough tape winding device 3 disposed immediately in front of the tape assembly 4, and then directed to the unit collection cap 5. Now, for each subunit, use the SZ twisting device 9.
If the number of rotations N of the frames or the accumulation length l are made different, the phase and pitch of twisting will be different between the multiple subunits joined at the unit assembly cap 5, and therefore the capacitive coupling value between the subunits will be different. As a result, the crosstalk characteristics of the product unit cable, which is collected and twisted by the pulling device 7 and then wound by the winding device 8, is improved. However, in this case each subunit is
Since the strands are completely SZ-twisted instead of using wobbling, which gives a reciprocating oscillation twist of 360 degrees or less, there is no twisting or misalignment of each stranded wire core as in the conventional method. Even during collective twisting, there is no risk that the twists of the subunits S will break. FIG. 4 shows that by imparting a twist to each of the stranded wire cores forming the subunit S, the twist pitch of each stranded wire core is changed to make the pitches different from each other, and as a result, the electrical characteristics of the subunit, FIG. 4 is a diagram illustrating a method for improving the crosstalk characteristics of the unit. In this figure, various twisting devices 21, 22, 23 are shown to omit the number of drawings.
and 24 are drawn for each stranded wire core, but this is of course for illustrative purposes only, and any one type of twisting device will suffice. Now, the twisting device 21 has rollers arranged in a staggered manner on a frame, and the rollers are gripped so as to allow the filament to run but prevent rotation, and the frame is moved around the axis of the filament. Rotate forward and backward to
This imparts SZ torsion to the striatum. The twisting device 22 has a similar construction, but the frame rotates in one direction about the axis of the filament. The twisting device 23 includes a twisting roll 23 rotatably disposed with its central axis forming an angle α with respect to the running direction of the filament. Now, referring to FIGS. 5a and 5b, it is assumed that the filamentous body begins to come into contact with the twisting roll 23 at point A and separates at point B. The distance between AB is AB=γθ/sinα. The striatum starts contacting the twisting roll 23 at this point A and then moves to B.
It receives a force that causes it to roll in the direction of AM until it reaches a point. Due to the tension in the striatum, the part of the striatum that begins to make contact at point A actually arrives at point B without going to point M, but during this time, that part
If it were to roll sideways, it would receive a rotational force equivalent to rolling across a distance. In other words, if the outer diameter of the striatum is D,

[Formula] undergoes twisting at an angle of . However, 0<α<
When π/2, it is an S twist, and when π/2<α<π, it is a Z twist.If the twist roll 23 is periodically swung as shown by the solid and broken lines in FIG. α periodically fluctuates within the above range, and the stranded wire core Q sent out from the delivery bobbin 14 undergoes an alternating twist of SZ before entering the segment plate 2. The twisting roll 24 in FIG. 4 is a device that does not swing periodically, and the diameter of the twisting roll or the set inclination angle of each stranded wire core is slightly changed, so that the pitch of each stranded wire core is adjusted relative to each other. It makes a difference. As detailed above, according to the present invention, each subunit to be assembled into a unit is given an SZ twist with a different pitch, thereby eliminating the twisting and misalignment of the stranded core due to wotting, which was conventionally seen. Furthermore, the untwisting of subunits during unit collective twisting is eliminated, and a communication cable with excellent crosstalk characteristics can be obtained.

[Brief explanation of drawings]

Fig. 1 is a simplified plan view showing a conventional tandem type communication cable manufacturing method, Fig. 2 is a similar view showing an embodiment of the present invention, and Fig. 3 is a diagram used in the present invention.
FIG. 4 is a plan view showing an example of the SZ twisting device, FIG. 4 is a simplified plan view showing a modified embodiment of the present invention, and FIGS. Q...Twisted wire core, S...Subunit, 4,5
...Collective cap, 3...Rough roll, 9...SZ twisting device.

Claims (1)

[Claims] 1. A method for manufacturing a tandem assembly type communication cable, in which a plurality of twisted stranded wires or twisted pair wires are twisted together into a subunit, and a plurality of the subunits are collectively twisted by take-up rotation to form a unit. After rough winding of each of the sub-units, different pitches are applied to each sub-unit before assembly.
A method for manufacturing a communication cable, characterized by providing SZ collective twist.