JP2592917B2 - Method and apparatus for identifying core of communication cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to a case where a communication cable is connected to a connector or a connection terminal of various communication devices, or when communication cables are directly connected to each other. The present invention relates to a method and an apparatus for identifying a core of a communication cable, which can automatically and accurately identify a communication cable.

2. Description of the Related Art In general, a communication cable is formed by bundling a large number of core wires. Particularly, in a telephone communication cable, in order to prevent crosstalk, two core wires are twisted two by two to form a pair. When such a communication cable is connected to a connector or a connection terminal of various communication devices, or when communication cables are directly connected to each other, it is a matter of course that each core must be accurately selected at both ends of the cable. In other words, the communication quality cannot be maintained unless each pair line is selected and connected.

For this reason, conventionally, a worker identifies a color pattern or a mark of a core wire covering, arranges each core wire in a predetermined order, and performs a connection work, thereby executing a correct wiring while maintaining a pair wire relationship. Was.

"Problems to be Solved by the Invention" By the way, in the above-described conventional cord identification method,
It is necessary to visually read the color patterns and marks on the core covering with a diameter of 1 mm or less.This operation is extremely inefficient, and the working conditions become severe as the number of cores increases. There was a problem that fatigue increased.

In order to overcome such a situation, with the recent development of automation technology, technology development for automation of core identification has been promoted.

For example, an image input device such as a camera or an image sensor is used to recognize and process the color patterns and marks of the core wire, first identify the core wires one by one, and then compare the respective core wires with each other to form a pair. Some attempt to identify line relationships.
However, in this method, it is necessary to fix the target core within the range of the depth of the subject of the image input device and to keep the surrounding lighting conditions constant, and the color pattern or mark of the core is not required to be the target core. When hidden behind the line, the image input device or the target core must be moved to fit within the field of view, and at this time, the lighting conditions must not be changed. Has the drawback that requires advanced technology and complicated equipment configuration.

In addition, there is a simple method to identify each core by checking the energization between both ends of the cable.However, since this method cannot identify the pair, it is used for cable inspection after the connection is completed. There is only.

As described above, the technology for identifying a pair wire has not been put to practical use yet, and the development of a new technology has been desired.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a communication cable core identification method and device capable of automatically and accurately identifying a paired line such as a telephone communication cable with a simple configuration.

[Means for Solving the Problems] The invention described in claim 1 is a communication cable having a main structure in which two core wires are twisted two by two to form a pair, and these are bundled in a multi-pair form. In the core wire identification method, a single AC electric signal of a predetermined frequency or two or more types having different frequencies between one end of one arbitrarily specified one of the core wires and the earth bus. And applying an AC electric signal to each of the cores other than the designated core, and inducing an induced electric quantity between each of the cores other than the designated core and the ground bus in accordance with the degree of electromagnetic coupling with the designated core, excluding the designated core. Is detected at one end side of each of the cores, and the cores other than the designated core having the maximum amount of induced electricity are determined to be the cores paired with the designated core. . The invention described in claim 2 is a core identification device for a communication cable having a main configuration in which two cores are twisted two by two to form a pair, and these are bundled in multiple pairs. Switch means for sequentially selecting two core wires arbitrarily from a plurality of core wires of a communication cable; and one of the core wires selected by the switch means as a designated core wire, and AC signal driving means for applying a single AC electric signal of a predetermined frequency or two or more kinds of AC electric signals having different frequencies between one end and a ground bus, and the designated core selected by the switch means Of the induced electric quantities induced between each of the other cores and the ground bus, the induced electric quantity of the frequency component corresponding to the AC electric signal applied by the AC signal driving means is calculated for each of the other than the designated core. One end of the conductor Measuring means for measuring, while holding the measured values obtained from each core wire other than the designated core wire by the measuring means, and comparing the held measured values with each other, the induced electric quantity is the largest Determining means for determining a core wire other than the specified core wire as a core wire paired with the specified core wire;

According to the above-described method or apparatus, the electromagnetic wave between one arbitrarily designated core wire and the core wire twisted with the designated core wire among the respective core wires of the communication cable. Since the maximum coupling is maximum, an AC electric signal of a predetermined frequency is applied between one end of the designated core wire and the ground bus, and the induced electric quantity induced in each of the core wires other than the designated core wire is the largest. Can be determined as a paired core with the designated core.

"Example" Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention. In this figure, reference numeral 1 denotes a cable to be identified, which is composed of a plurality of core wires 1a, 1b, 1c,. 2 is a switch circuit for arbitrarily selecting two core wires from a plurality of core wires 1a, 1b, 1c,... And connecting the other core wires to a ground bus. 2b,
2c,... Reference numeral 3 denotes one of the two core wires selected by the switch circuit 2, one of which is connected to an oscillator (AC signal driving means) 4 for outputting an AC electric signal of a predetermined frequency (fc), and the other is a narrow band amplifier 5. Is a switch circuit connected to. The narrow-band amplifier 5 selectively amplifies the oscillation frequency (fc) of the oscillator 4 in the AC electric signal supplied via the switch circuit 3. A circuit for measuring the amount of induced electricity is constituted by the smoother 6, the DC amplifier 7, and the A / D (analog / digital) converter 8. Reference numeral 9 denotes a comparison / determination circuit provided with means for holding the input measured values, and reference numeral 10 denotes a switch control circuit that switches between the switch circuits 2 and 3 based on a command from the comparison / determination circuit 9.

FIG. 1 shows a state in which the cores 1a and 1b are selected, wherein the core 1a is connected to the oscillator 4 and the core 1b is connected to the narrow band amplifier 5. Also, the comparison judgment circuit 9
Output the identification result to a display device (not shown) or another device.

Next, the operation of the first embodiment will be described.
First, a command is issued from the comparison / determination circuit 9 to the switch control circuit 10, and the switch circuits 2 and 3 are switched to form one core.
Command 1a and connect to oscillator 4. Next, in the switch circuits 2 and 3, the contacts other than the contacts connected to the core wire 1a and the oscillator 4 are switched, and one core wire 1b other than the core wire 1a is arbitrarily selected and connected to the narrow band amplifier 5. . At this time, all the cores except the cores 1a and 1b are disconnected from the oscillator 4 and the narrow band amplifier 5, and are connected to the ground bus. With this configuration, since the cores other than the two cores to be measured are grounded with low impedance, fluctuations in potential can be reduced, and measurement can be performed with high accuracy. On the other hand, since the frequency fraction characteristic of the narrow band amplifier 5 is set so as to selectively amplify the oscillation frequency (fc) of the oscillator 4, an extraneous component having various frequency components different from the frequency fc induced in the core wire 1a is provided. The noise is cut off, and only the frequency component of the oscillator 4 is amplified, and this is extracted by the rectifier / smoothing device 6 as a DC component substantially proportional to the magnitude of the output of the oscillator 4 induced on the core wire 1b. This is a DC amplifier 7
The signal amplified by the A / D converter 8 and digitized by the A / D converter 8 is input to the comparison / determination circuit 9 as a measured value. The comparison and judgment circuit 9 temporarily holds the measured value for each core, and sequentially gives a command to the switch control circuit 10 to sequentially perform the same switch operation and measurement for all cores other than the core 1b. The values are compared with each other to identify one core wire having the maximum measured value, and this is determined and identified as a core wire paired with the designated core wire 1a. In addition, the designation is changed to a core wire other than the core wire 1a whose pair has not yet been specified, and the same switching device and measurement are repeated. Identify.

As means for the comparison / determination circuit 9 to hold the measured value for each core, there may be a means for storing all the measured values of each unspecified core for one designated core. The temporary holding means is sufficient for this purpose, and the procedure of holding only one measured value, comparing it with a new measured value, and holding the larger value and discarding the smaller value is sequentially repeated. Can be identified.

In the first embodiment described above, by connecting all the cores except the cores 1a and 1b to the earth bus by the switch 2, the measured value between the core paired with the core 1a and the earth bus is reduced. Although an example of a configuration in which a significant difference in signal-to-noise ratio is obtained with respect to the measured value between the core wire other than the target and the ground bus has been described, depending on the conditions such as the cable length and equipment usage environment, Not only the configuration but also a configuration in which the cores other than the two cores to be measured are in the open state is possible.
In addition, as the narrow band amplifier 5, an ordinary means for selectively amplifying only a single frequency, for example, a tunable amplifier can be used. Further, as shown in FIG. 2, a band is provided on one or both of the input side and the output side of the amplifier 51, for example, by using a normal amplifier 51 and a bandpass filter 52 instead of the narrow band amplifier 5 to constitute a device. By arranging the filter 52, it is possible to take out only the frequency component of the oscillator.

FIG. 3 is a diagram showing that the effective frequency depends on the length of the target cable in the embodiment shown in FIGS. 1 and 2 described above. Area A ₂ is an illustration the range of desired relationship of the AC signal frequency and cable length, favorably detects the signal, which is a region that can identify the core wire. Region A ₁ is the signal level is small S / N ratio is bad area, the area A ₃ is an unstable region signal level resonance point appears. Area A ₂ when the cable length is short has high frequency, although a tendency to be low when the cable length is long, the first view this relationship, a plurality of cores 1a, 1b, 1c, ... line This is a frequency characteristic that can be understood also by considering it as a distributed constant circuit of the inter-floating point C and the internal inductance L. Based on such characteristics, by using two or more oscillation frequencies, it is possible to realize a device capable of identifying a core wire over a wide range of cable lengths. Namely, first frequency, for example, when only by f ₂ is the cable length that can be identified remains in the range from l ₂ to L _2, the use of the second frequency, for example, f ₁ and f _3, cable length discernible l from the l ₁ to L ₃ from ₃ L ₁
Consisting l ₃ is the sum of the range up to a wide range of up to L _1.

FIG. 4 is a diagram showing the configuration of the second embodiment utilizing this relationship. In this figure, instead of one oscillator 4,
An oscillating unit 40 including oscillators 40a and 40b oscillating at different frequencies from each other is provided. Instead of one narrow-band amplifier 5, a narrow-band amplifier 50 including narrow-band amplifiers 50a and 50b having different bands is provided. Further, switches 41 and 53 for switching the transmission frequency of the transmission unit 40 and the band of the narrow band amplifier 50 according to the cable length are provided.

In this second embodiment, instead of using a plurality of oscillators 40a, 40b, one oscillator oscillating at a plurality of different frequencies is used.
A configuration using multiple multi-frequency oscillators is also possible. In this case, the narrow-band amplifier 50
You only need to switch between them. If necessary, the frequency response characteristics of the rectifier / smoothing device 6 can be switched in accordance with the measurement frequency. Similarly, if necessary, the gain of the DC amplifier 7 can be switched according to the measurement frequency. Further, it is also possible to adopt a configuration in which a plurality of rectifying / smoothing devices 6 and DC amplifiers 7 are provided corresponding to a plurality of frequencies, and a switch 53 is arranged between the DC amplifier 7 and the A / D converter 8. Also, the narrow band amplifier 50a,
Various concrete means of 50b can be conceived, not only by a tuned amplifier, but also by a series connection of an amplifier and a bandpass filter as already shown in FIG.

In each of the above-described embodiments, the voltage measurement has been described as an example of the method of detecting the amount of electricity induced by the electromagnetic coupling between the two core wires. The basic configuration of the device of the present invention does not change at all only in the details of the present invention. In addition, comparison of measured values is performed by a digital circuit, but comparison of measured values is performed using an analog arithmetic circuit that performs voltage value accumulation, magnitude comparison, etc., without using an A / D converter, using analog signals as they are. Can be easily realized by ordinary circuit technology.
The scale of the device of the present invention is not only as simple as that of the device based on the energization check cited as an example of the above-mentioned prior art, but also in using the device of the present invention, only one end of the communication cable is connected to the device of the present invention. There is an advantage that workability is good because it is only necessary to connect and the pair wire can be specified while the other end is open.

[Effects of the Invention] As described above, according to the method and apparatus of the present invention, automatic identification of a paired line such as a telephone communication cable, which has been impossible in the past, by a machine using a simple circuit configuration is performed. For example, while the other end of the cable wound on the drum is open, it can be easily carried out only by catching one end of the cable. As a result, the pair of core wires at one end of a telephone communication cable or the like can be formed. Connection is possible only by grasping, and it is not necessary to identify core wires one by one as in the related art, and the effect that the connection work can be sped up can be obtained. Also, at the other end of the cable, it is necessary to check one end of the already connected cable and one core at a time, but this is done by checking the energization (a common line, A method of confirming the energization one by one may be combined. Furthermore, if the method and apparatus of the present invention are used in combination with a mechanical automation technique such as core wire gripping / manipulation, a telephone communication cable or the like is connected to a connection terminal of a communication device, or a connector is connected to a terminal of the communication cable. This makes it possible to completely automate a cable connection operation performed for the purpose of connecting cables or connecting communication cables directly to each other.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of a modification using an amplifier 51 and a bandpass filter 52 instead of the narrow band amplifier 5 of the embodiment. FIG. 3 is a graph showing the tendency that the effective frequency is dependent on the length of the target cable in the embodiment. FIG. 4 is a diagram showing the configuration of the second embodiment of the present invention applicable to cables of a wide range of lengths. FIG. 1 ... Cable, 1a, 1b, 1c, ... Core wire, 2,3 ... Switch circuit (switch means), 4 ... Oscillator (AC signal drive means), 5 ... Narrow band amplifier, 6 ... Rectification・ Smoothing device, 7 ... DC amplifier, 8 ... A / D converter (5 to 8 are measurement means), 9 ... Comparison judgment circuit (judgment means), 10 ... Switch control circuit, 40 ... Oscillator , 40a, 40b ... oscillator, 50 ... narrow band amplifier, 50a, 50b ... narrow band amplifier, 41, 53 ... changeover switch.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hirokazu Yokota 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (56) References JP-A-51-127392 (JP, A)

Claims (2)

(57) [Claims] 1. A twisted pair of two core wires to form a pair wire,
In a method for identifying a core of a communication cable in which these are bundled in a multi-pair form, a single unit of a predetermined frequency is connected between one end of one specified core and an earth bus, among the cores. One AC electric signal or two or more types of AC electric signals having different frequencies from each other are applied, and the degree of the electromagnetic coupling between the specified core and the specified core between the core other than the specified core and the ground bus. An induced electric amount induced in response to the detected core is detected at one end of each of the cores other than the specified core, and the core other than the specified core having the largest induced electric is paired with the specified core. A method for identifying a core of a communication cable, wherein the core is determined to be a core. 2. A twisted pair of two core wires to form a pair wire,
In a core identification device for a communication cable having a main configuration obtained by converging a plurality of the cores, a switch means for sequentially selecting two arbitrary cores from a plurality of cores of the communication cable, and the switch means One of the core wires selected by the above is designated as a designated core wire, and a single AC electric signal of a predetermined frequency or two or more types of AC electricity having different frequencies between one end of the designated core wire and the earth bus. AC signal driving means for applying a signal, of the induced electric quantity induced between each core wire other than the designated core wire selected by the switch means and a ground bus, applied by the AC signal driving means. Measuring means for measuring the induced electric quantity of the frequency component corresponding to the AC electric signal at one end of each of the cores other than the designated core; and Holding the measured values, and comparing the held measured values with each other to determine that a core wire other than the designated core wire having the largest induced electric quantity is a core wire paired with the designated core wire. And a means for identifying a core of a communication cable.