JPH02228573A - Inspecting device of conductor joint in switching device of communication line - Google Patents

Abstract

PURPOSE:To accurately inspect in a short time the state of connection of a connector half, a conductor probe, etc. with a conductor in a switching device of a communication line by providing an operational amplifier, a voltage output means and first, second and third resistor. CONSTITUTION:In a conductor joint inspecting device 40, common terminals (c) and terminals (b) of change-over switches 41 and 42 operating in linkage are connected with each other when a conductor switching process is conducted, while the common terminals (c) and terminals (a) thereof are connected with each other when the inspection of a conductor joint is conducted. All resistor 44, 45 and 47 have the same high resistance value. In a feedback loop of an operational amplifier 46, a second resistor, a lead wire, a conductor joint, a conductor, a joint, a lead wire and a third resistor are interposed in series sequentially. As the result, a gain of the amplifier 46 changes sharply when there is any contact fault in the conductor joint, and accordingly, the contact fault in the conductor joint can be detected from an output of the amplifier 46.

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to a switching device for communication lines, and in particular, for inspecting the connection state of the connection between a connector half and a core wire, or the connection between a probe and a core wire, etc. The present invention relates to a core wire connection inspection device.

``Prior Art'' As a switching device for switching a metal multi-pair cable used in a communication line to a friendly line without disconnecting the line, the inventor of this invention first developed the invention in 1986-117935.
An application was filed for the title of the invention: ``Communication line switching device.'' Hereinafter, first, this switching device will be explained.

Figure 2 is a block diagram showing the schematic configuration of the switching device;
The figure is a circuit diagram of the device, and FIG. 4 is a time chart showing the open/close states of each switch contact when switching the core. First, the overall configuration of this switching device will be schematically explained. It is constructed by twisting two core wires L1 and L2. (Please note that
In this figure, only one pair of wires is shown. ) Core wire switching connectors Δa and A b are connected to both sides of a switching point P planned in the middle of this existing core wire IO, and electrical continuity is established to the outside. The cordless wire 20 is similarly composed of 10 pairs of wires, and a wire switching connector Ac is connected to the core wires Lla and L2a constituting each pair at the scheduled switching position. In addition, these connectors A a, A b, AC
The mechanism and connection switching method using these are disclosed in Japanese Patent Application No. 145087/1987. Connection lines are output from each of the above-mentioned connectors to the switching device 30.

The configuration of the switching device 30 includes a relay circuit section 31, a switching section 32, a wire number confirmation section 33, a transmission section 34, and a CPU section 3 upper 5
It is what it is. The relay circuit section 31 includes a plurality of contact relays, and the switching section 32 includes a photocoupler type variable resistance element, a static characteristic measurement unit for measuring the current-resistance characteristic of the variable resistance element, and a static characteristic measurement unit for measuring the current-resistance characteristic of the variable resistance element. Based on the discrete current-resistance characteristics obtained from the unit, a pair of It consists of an unbalance measuring unit for checking whether the variation in the reproduced resistance value of the variable resistance element is within the permissible range. The line number confirmation unit 33 is connected to the existing line 10, transmits and receives a minute signal that does not affect communication to and from the station at the other end, and performs line number comparison. The transmission section 34 communicates between the stations at the other end via the empty circuit 37 for line number comparison.

The 020 unit 35 is for overall control of the above-mentioned switching operation, and performs static characteristic measurement, unbalance measurement, and data processing necessary for these measurements, and also sequentially performs core wire switching connection by switching relay contacts. Has a function.

Next, this embodiment will be explained in more detail based on FIG. In this figure, the code l is the CPU (central processing unit)
, 2 is a program for control function calculations and a series of sequential operations. c! A memory consisting of a ROM and a RAM primarily for storing static characteristic data. 3 is a photocoupler unit, which has a D/A (D/A) for capturing voltage data corresponding to the resistance value of the variable resistance element.
A digital/analog) converter 4, a V/I (voltage/current) converter circuit 5 that outputs a current I corresponding to the output voltage of this D/A converter 4, and a It is composed of a photocoupler 6 (variable resistance element). In addition, the photocoupler 6 uses the above-mentioned current! It consists of an LED 6a through which light is emitted, and a CdS 6b that receives the light from the LED 6a. A photocoupler unit 7 has the same configuration and function as the photocoupler unit 3, and is composed of a D/A converter 8, a V/1 conversion circuit 9, and a photocoupler 10.

SW l ~SW7. S L l, S L 2. Sai
, Sbi, Sei, S Ni, and S ci (where i is the switching core logarithm) are switches that are sequentially turned on and off by the CPUI, and the connection state shown by the solid line indicates the case of non-excitation. Reference numeral 12 denotes a static characteristic measuring unit, which is composed of a resistor 12a and an A/D (analog/digital) converter 12b that converts the voltage across the resistor 12a into digital data. Also,
In this unit 12, the terminal T l l + 'I''
l* are terminals to which voltages +V and -V are applied, respectively. 13 is an unbalance measurement unit, and amplifier 1
3a and a comparator 13b. In this case, the comparison 113b compares the output of the amplifier 13a with the constant voltage Vk.
Compare and amplify “”? -"+ 13a outputs an "O" signal when the absolute value of the output is smaller than the voltage Vk, and outputs a "1" signal when the absolute value is greater than the voltage Vk. It is output to the pass line la of the CPU 1. Note that Vk is a value determined experimentally.The unit 13 has +V and -V power supplies, and the connection lines are connected from terminals T13 and T14, respectively. , voltages +V and -V are applied.

Next, the operation of the switching device having the above configuration will be explained. Prior to cable switching, wire number comparison is performed.

This is SW8. SW 1,5ai (1≦i≦1<))
is turned ON, the wire number comparison unit is connected to the existing core wire via the connector Aa, and minute signals are transmitted and received between the stations at the other end to perform wire number comparison.

When the wire number comparison is completed, the SW8. SW1, Sa
i is turned off, and the characteristics of the photocoupler type variable resistance element are measured.

That is, before actual switching, this switching device goes through two modes: (1) static characteristic measurement mode and (2) dynamic characteristic measurement mode, and then shifts to cable switching mode. Each mode will be explained in turn below.

■ Static characteristic measurement mode This mode is a mode for measuring each static characteristic of the photocoupler 6.10. In this mode, the CPUI first turns on each of the switches 5W2-1 and 5W2-2 (dotted line state). As a result, one end of the CdS.6b is connected to the terminal T of the static characteristic unit 12 via the switches 5w2-1, 5w5-1.degree. 3W7-2 to one end of the resistor 12a in the static characteristic unit 12. That is, the CdS 6b and the resistor 12a are connected in a series circuit, and voltages V and -V are applied to both ends thereof, respectively.

Next, the CPUI sequentially outputs specific discrete data to the D/A converter 4, thereby causing a current of, for example, 0.05Δ, 0.1Δ, 0.15A, etc. to flow through the LED 6a. The output data of A/D conversion ¥312b at this time is taken into the memory 2. Here, each data taken into the memory 2 indicates the resistance value of the CdS 6b when each of the above-mentioned currents is passed through the LED 6a. The above is the process of measuring the static characteristics of the photocoupler 6.

Next, the CPU turns off the switches 5w2-1 and 5w2-2, and then turns off the switches swa-t and 5W3-2.3W.
7-1. ．． 5W7-2 are each turned on (dashed line state).

This connects the CdS 10b to the static characteristic unit 12. Next, the CPUI measures the static characteristics of the photocoupler 10 in the same manner as described above.

■Dynamic characteristic measurement mode In this mode, the CPU first selects the switch 5W2-
1.2-2.8W3-1.3-2.3W5-1.5-2
, 5W6-1, 6-2 are each turned on, and the other switches are turned off. This results in CdS・6b.

tab are connected in series, and one end of CdS 6b is connected to terminal T1° of the unbalance measurement unit 13.
The connection point of S.6b and 10b is connected to the input end of the amplifier 13a in the same unit 13, and the other end of CdS.10b is connected to the terminal TI4 of the unbalance measurement unit 13, respectively. With this connection, voltage +■ is applied to both ends of the CdS 6b, 10b series circuit.

(2) is applied, and the voltage at the connection point between CdS 6b and 10b is applied to the comparator 13b via the amplifier 13a. Next, the CPU changes the resistance values of CdS 6b and 10b with the speed and smoothness required when switching cables. This resistance value change is performed while calculating a control function based on static characteristic data. That is, first, Cd
Set the resistance value of S・6b and job to the maximum value. Specifically, C(Is・6b.

D/A data such that the resistance value of 10t1 is the maximum value
Output to converters 4 and 8, respectively. Next, CdS・6b, lo
The value of the drive current that makes the resistance value of b slightly lower than the maximum value is calculated, and the resistance value is set based on this value. Similarly, the resistance values of GdS 6b and job are sequentially decreased.

Next, the resistance values of CdS・6b and lOb are increased in sequence.

In the above process, the respective resistance values of CdS·6b and fob will become inconsistent unless they sequentially decrease/increase while taking the same value. When the values are sequentially decreased/increased while maintaining the same value, the output of the amplifier 13a is always 0 because the balance is maintained, and therefore the output of the comparison Wl 13b is always a "0" signal. However, due to reasons such as the fact that the current-resistance characteristic of the photocoupler is actually nonlinear, the static characteristic is obtained using linear interpolation, and the response speed of the photocoupler 6 and IO are different. CdS・6b, lOb
A difference (imbalance) occurs in the resistance values of the two. If this unbalance becomes thicker than a certain level, it disturbs the transmission characteristics of the core wire when switching cables, causing negative effects such as bit errors.

Therefore, in the switching devices shown in FIGS. 2 and 3, Comparison 1
13b, the absolute value of the output of the amplifier Pi 113a and the constant voltage VK are constantly compared, and if the absolute value of the amplifier 13a is greater than the voltage VK, that is, the comparator 1
When the output of 3b becomes the "l" signal, the CPU displays this on the display section (path shown in the figure) and at the same time stops the measurement, or returns to measuring the static characteristics again.

As a result of the above measurements, if the resistance unbalance amount does not fall within a predetermined value, measures such as replacing the photocoupler 6.10 are finally taken. Note that the resistance unbalance amount is determined by data on the communication line, and is more likely to be determined experimentally.

The above is the process of measuring dynamic characteristics. Note that, although a detailed explanation will be omitted, a function may be added to verify the resistance value itself achieved by the control function during this mode.

■Cable switching mode This mode is an operation mode for actually performing cable switching, and is performed after the above-mentioned static characteristic measurement and dynamic characteristic measurement are completed.

The actual switching operation will be explained with reference to the time chart in FIG.

First, switches SW l and SW2 are OF F r S
a r + S bi, S ci, S Ni are OFF
In this state, at time t1 in FIG. 4, the switch 5ei (i=
1 to 1 O) are simultaneously turned ON. As a result, a switch Sei is inserted in parallel at each switching point of each existing core wire. In this state, at time t, the switching points P of all the core wires are cut at the same time. And No, l to No
, 1 The pairs of wires up to lO are sequentially switched to the newly installed core wires.

Note that since the connection is normally switched for each IO pair, 1=IO.

Note that these operations are performed under the control of the CPU section 35 while being synchronized on the A side and B side in FIG. That is, a switching device similar to that on the A side is prepared on the B side so that the same resistance change can be made.

(1) At time t, switch Sal and switches Scl, S L l, and S L2 of pair lines No. 1 and 1 are turned on. As a result, each core wire Ll, L2 of pair wire No. 1
, between the connectors Aa and Ac, that is, the existing core wire lO
CdS 6b and 10b, which are variable resistance elements, are inserted between the remaining side of the cable and one end of the newly installed core wire 20, respectively.

The values of these variable resistors should be set to the maximum value in advance (.

(2) From time [, to t4, the resistance value of each variable resistance element is decreased. If the realized resistance values are not always equal, line balance will be disturbed.

(3) Time t when the resistance value of each variable resistance element becomes low resistance
4, turn on switch SNI to short-circuit between connector Aa and AC. As a result, the existing core 10 and the new core 20
are connected.

(4) Switch Scl is turned off at time t, while switches Sbl, ON, S L l, S L2 are turned on at time t.
Turn off. As a result, the switch SLI is switched from the newly installed side to the existing side. Connectors Aa and Ab
CdS・6b and lOb are inserted between the two.

(5) In this state, turn off the switch Sel at time t7.
In this case, CdS 6b and lOb are inserted in series between the remaining side and the discarded side of the existing core wire lO.

(6) Increase the resistance value of the variable resistance element from time (, to t).

(7) At the time when the resistance value of the variable resistance element becomes high,
Turn off switches Sat and sbt. As a result, the CdS 6b and fob are separated from the existing core 10 and the new core 20, and the remaining side and the discarded side of the existing core 10 are separated. On the other hand, the connectors Aa and 8c1, that is, the remaining side of the existing core wire 10 and one end of the new core wire 20 are maintained in a connected state by the switch SN.

In this way, once the switching of the pair wire No. 1 is completed, the switching of the pair wire No. 2 and subsequent ones is performed by the same operation. And the time shown in Figure 4. At time t, the multi-core wires on the existing side and the new side are connected (this connection is made by connecting the connector halves shown in the figure all at once), and at time t,
switches SN, ~SN, which connected the above-mentioned core wires to. Turn off. When the switching is completed in this way, the CPU section 35 and the like return to the initial state at time tll, and the operation ends.

The above are the details of this switching device. Needless to say, in the cable switching process, it is desirable to change the resistance values of CdS 6b and job as minutely (smoothly) as possible.

"Problems to be Solved by the Invention" In the switching device described above, the connector Aa is composed of a connector half Ca and a connector probe Cp, as shown in the upper part of FIG. In addition, in this figure, only those corresponding to the l core wire are shown.

The connector half Ca is provided with a pressure contact that is pressed into contact with the core wire, a joint contact J that is coupled to another connector half, and a conductor that connects these contacts. Further, the connector probe Cp is configured to be detachably attached to the connector half Ca, and when the connector half Ca is coupled, the lead wire RD is connected to the conductor. Further, the connector Ab is constituted by a core wire probe Sp (FIG. 1). The contact portion S8 of the core wire probe Sp is brought into contact with the core wire, and the lead wire RD and the core wire are electrically connected.

By the way, when line switching is performed by the above-mentioned switching device, the pressure contact of the connector half C island and the contact portion Ss of the core wire probe Sp must each be reliably electrically connected to the core wire.

Therefore, the present invention provides a pressure contact and a contact portion Ss.
It is an object of the present invention to provide a core wire connection inspection device in a communication line switching device that can inspect the contact state of the connection between the wire and the core wire prior to switching connection.

"Means for Solving the Problem" The present invention includes an operational amplifier, voltage output means for supplying a constant voltage to a first input terminal of the operational amplifier, one end of which is grounded, and the other end of which is connected to a second input terminal of the operational amplifier. the first connected to the input end
a second resistor having one end connected to the second input terminal of the operational amplifier, and a third resistor having one end connected to the output terminal of the operational amplifier; 2. Third
The other end of each of the resistors is connected to the end of a lead wire connected to one core wire of the existing line via a switching means and a switching element.

"Operation" According to the present invention, the feedback loop of the operational amplifier includes the second resistor, the lead wire, and the core wire connection section.

A core wire, a core wire connection portion, a lead wire, and a third resistor are sequentially inserted in series. As a result, if there is a contact failure in the fiber connection part, the gain of the operational amplifier increases (changes), and therefore, a contact failure in the fiber connection part can be detected from the output of the operational amplifier.

"Embodiment" Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram showing a communication line switching device equipped with a fiber connection inspection device 40 according to an embodiment of the present invention. Note that the switching device shown in this figure has the same configuration as the switching device shown in FIGS. 2 and 3, except that the fiber connection inspection device 40 is provided. The same reference numerals are given to the parts corresponding to each part in Fig. 3.In addition, in this figure, only the switch corresponding to one of the wire pairs, L1, is shown for the wire changeover switch. and the switch S a corresponding to the i-th pair
i, S l) Only the i and switch SLI are described. Although this figure only shows the fiber connection inspection device 40 that processes one fiber Ll side, in reality, an inspection device 40 that processes the fiber L2 side is provided. That is, two sets of inspection devices 40 are provided within one switching device.

In the fiber connection inspection device 40, reference numerals 41 and 42 are changeover switches that operate in conjunction with each other, and the common terminal C and the terminal C are connected when performing the fiber switching process, and the common terminal C and the terminal C are connected when performing the fiber connection inspection. Terminal C and terminal a are connected. 44 and 45 are resistors connected in series, one end of the resistor 44 is connected to the terminal a of the changeover switch 41, the connection point of the resistors 44 and 45 is connected to the inverting input terminal of the operational amplifier 46, and the other end of the resistor 44 is connected to the terminal a of the changeover switch 41. The end is grounded. 47 is a resistor, one end is connected to the other end a of the changeover switch 42, and the other end is connected to the operational amplifier 4.
It is connected to the output terminal of 6. Each of the above resistors 44, 45
．． All 47 have the same high resistance value (for example, 100KΩ)
resistance. 48 is a capacitor inserted between the input and output terminals of the operational amplifier 46. 49.50 is a voltage dividing resistor that divides the constant DC voltage +V, and the voltage 8 (for example, 100 mV) obtained by this voltage division is the operational amplifier 2i1.
46 non-inverting input. Further, 51 and 52 are power supplies for the operational amplifier '1s46.

Next, the operation of the circuit described above will be explained. When inspecting the core wire connection portion, first, each common terminal C of the switch switches 41 and 42 is connected to the terminal a. Then switch Sal
, Sbl are turned on, and the output of the operational amplifier 46 is checked. Now, when the core wire connection part, that is, the connection part between the insulation displacement contact of the connector half Ca and the core wire, and the contact part between the contact part SII of the core wire probe Sp and the core wire are both maintaining a good connection state. In this case, a series circuit of resistors 44 and 47 is inserted into the feedback loop of operational amplifier 46. As a result, the output Vo of the operational amplifier 46
However, Vo=Vg(1+""R4') R4° (However, R44+R411+R4? are the values of resistors 44 and 45.47, respectively). Here, as mentioned above,
R44= R4s= R4? Therefore, Vo=3Vs. On the other hand, if there is a contact failure in the core wire connection part, the gain of the operational amplifier 46 becomes ■, and its output Vo becomes positive?
1 source voltage. That is, by checking the output Vo of the operational amplifier 46, it is possible to detect a contact failure at the core wire connection portion. Incidentally, by the above-mentioned check, a connection failure between the connector half Ca and the connector probe Cp can of course be discovered.

Next, switch Sa2. Only Sb2 is turned on, the output (2) of the operational amplifier 46 is checked, and the same process is repeated to inspect the state of contact between each core wire, the connector half, and the core wire probe.

In the embodiment described above, when the contact condition is normal, the current i flowing through the core wire is as follows: i=Vs/R4°=100V/100KΩ=lμA, which is an extremely small current. Further, when a contact failure occurs, the current i becomes 0. Furthermore, since the inspection device 40 is provided corresponding to each of the two core wires that make up the pair, no voltage is applied between the two core wires that make up the pair. As a result of the above, even if the above-mentioned inspection device 40 inspects the fiber connection portion while the data transmission line is in use, there will be no adverse effects such as occurrence of bit errors on the data transmission line.

In addition, the data transmission line (MODEM: 300-9600
゜DSU: 3.2K ~ 64Kbit/5ea)
We conducted a test at , and no bit errors occurred (we were able to inspect the connections).

In the above embodiment, the core wire probe Sp is used, but when switching again, this core wire probe S
A connector probe is used instead of p.

"Effects of the Invention" As explained above, according to the present invention, the connection state between the connector half, core wire probe, etc. and the core wire in a communication line switching device can be accurately inspected in a short time.
As a result, the effect of improving the reliability of switching processing can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing the configuration of an embodiment of the present invention, and FIG.
FIG. 3 is a block diagram showing a schematic configuration of a conventional switching device for communication lines, FIG. 3 is a circuit diagram showing details of the switching device, and FIG. 4 is a timing chart for explaining the operation of the switching device. 6b. 0b... Cd5 (variable resistance element), 4 l, 4... Changeover switch, 44.45, 47.4 9.50... Resistance, 6... ...Operation amplifier, S Bi, S bi...Switch.

Claims (1)

[Claims] Connect the lead wires to each core wire of the remaining side of the existing line, the removed side of the existing line, and the new line through pressure welding connection means,
Switching elements are connected to the other ends of these lead wires, and the core wires to be switched are selected using these switching elements, and the core wires on the remaining side of the selected existing line and the core wires of the new line are connected. , a communication line switching device in which a variable resistance element is interposed between the remaining core wire and the removed core wire of the existing line, and the line is switched while changing the resistance value of the variable resistance element, which includes an operational amplifier; a voltage output means for supplying a constant voltage to a first input terminal of the operational amplifier; a first resistor having one end installed and the other end connected to the second input terminal of the operational amplifier; a second resistor connected to two input terminals; and a third resistor, one end of which is connected to the output terminal of the operational amplifier, and switches the other ends of the second and third resistors. A wire connection inspection device in a communication line switching device, characterized in that the wire connection portion inspection device is connected to an end of a lead wire connected to one wire of the existing line via the means and the switching element.