JPH0553329B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a communication line switching device for time-division multiplexing of a plurality of types of communication signals onto one communication line.

〔overview〕

The present invention provides a communication line switching device for time-division multiplexing of multiple types of communication signals on one communication line installed between two points, in which a communication line is connected to a first terminal, and a communication line is connected to a first terminal. A communication line for a communication signal with a high priority is connected to the second terminal, a communication line for a communication signal with a low priority is connected to the third terminal, and a communication signal arriving at the first and second terminals is detected. When there is an OR output of each output of the second signal detector, the first terminal and the second terminal are connected, and when there is no OR output of each output, the first terminal and the third terminal are connected. By doing so, switching is performed by detecting signals transmitted along with normal communication signals without the need for special switching signals, making it easy to interrupt high-priority communication signals. It is.

[Conventional technology]

Conventionally, multiplexing of communication lines has been performed using a frequency multiplexing method or a time division multiplexing method. In such a multiplexing method, the multiplexing equipment is complicated and expensive. In addition, since multiplexing is performed by assigning frequencies and time slots,
It is not possible to freely set the frequency band and dynamic range given to each communication line.

Recently, devices have come into use that read the values of meters installed in each home using telemetering signals using telephone lines and automatically calculate, for example, the amount of electricity used.

In addition, safety monitoring devices such as those provided by security companies and in-house safety monitoring devices in each home are similarly connected via telephone lines.
Methods of intensive safety monitoring are also being put into practical use.

[Problem that the invention seeks to solve]

However, with such conventional communication line multiplexing methods, when multiplexing telemetering signals, safety monitoring signals, etc., as in the example above, onto a telephone line, the signals are divided into frequency bands and dynamics as described above. There were other problems, such as the range being limited, and considering the frequency of use, it was not necessarily economical.

Therefore, in the prior art, in such a case, a method is used that includes a switching device that switches signals each time and multiplexes them in a time-division manner. That is, normally, the signal is connected to the main communication signal, and when a switching signal arrives, the signal is switched to the slave communication signal, thereby performing time-division multiplexing.

However, when the number of communication signals to be multiplexed increases, the switching signal detection by the switching device becomes complicated, and the switching control cannot be performed easily, resulting in a significant cost increase depending on the number of communication signals to be captured. This has the drawback of increasing the size of the switching device.

The present invention solves these conventional drawbacks by providing a switching device that is inexpensive, has few electrical limitations, can be easily switched to multiplex multiple communication signals, and is further compact. The purpose is to

[Means for solving problems]

The present invention relates to a state in which a communication signal passes between a first terminal and a second terminal through which one communication line connected between two points and through which a plurality of types of communication signals are transmitted in a time-sharing manner; In a communication line switching device comprising a switching circuit that switches and connects a state in which a communication signal passes between one terminal and a third terminal, and a control circuit that controls this switching circuit, the control circuit is a first terminal and a third terminal. a first signal detector that detects that a communication signal arrives at the terminal; a second signal detector that detects that a communication signal arrives at the second terminal; and the first and second signal detectors. and an OR circuit which receives each detection output as input, and when the OR circuit has an OR output, the switching circuit is set to a state where a communication signal passes between the first terminal and the second terminal. ,
The present invention is characterized in that, when the logical sum circuit does not have a logical sum output, the switching circuit is set to a state in which a communication signal passes between the first terminal and the third terminal.

[Effect]

The present invention prioritizes communication signals taken into each of two points, constantly connects lower priority communication signals to a communication line that is multiplexed via a switching device, and when a higher priority communication signal arrives. Furthermore, multiplexing of a large number of communication signals can be easily performed by detecting a signal transmitted along with the communication signal and switching to a communication signal with a higher priority.

That is, the signal detector of the switching device only needs to detect a specific signal of the communication signal, which simplifies the structure and makes the control method extremely easy.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a communication line multiplexing device in which the switching device of the present invention is used.
Point A is telephone office A, and point B is subscriber premises B.
It is. A subscriber line SL is connected to the terminal α of the switching device TSWa of the telephone office A via a signal detector DETb', and an exchange SW is connected to the terminal β via a signal detector DETa. A telemetering device TMRa is connected to the terminal γ. A signal detector is connected to terminal α of switching device TSWb in subscriber premises B.
A subscriber line SL is connected via DETa′, a telephone TE is connected to terminal β via a signal detector DETb, and a telemetering device is connected to terminal γ.
TMRb is connected. telemetering equipment
TMRb takes in data from electricity meter M and sends it to the communication line.

Here, telephone call signals are given higher priority than telemetering signals.

The feature of this multiplexing device is that when no communication is being performed, the switching devices TSWa and TSWb switch to the lower priority telemetering device TMR.
and is configured such that a telephone call signal is transmitted only when a telephone call is to be made. This is fundamentally different from the conventional method, which connects to the higher priority side when no communication occurs.

Signal detector of this switching device TSWa and TSWb
DETa and DETa′ are 16Hz ringing signals (TR)
is detected and the connection is switched to terminal α and terminal β. In addition, the signal detectors DETb and DETb' of the switching devices TSWa and TSWb detect the direct current loop (DCL) of the line closed by the telephone TE and
and terminal β. Therefore, a ringing signal (TR) arrives from the exchange SW, and the telephone
When the TE answers, the exchange SW and the telephone TE remain connected until the call ends and the DC loop (DCL) runs out.
is connected. When the call ends, the switching device automatically activates and switches to the telemetering side.

This configuration greatly simplifies the switching device TSW. That is, in order to perform telemetering, there is no need for any signal and control circuit to switch the communication line to the telemetering side in advance. When making a telephone call, the conventionally used ringing signal (TR) and closure of a direct current loop (DCL) can be utilized to preferentially and automatically utilize the communication line for the telephone call. The switching device for this purpose is simple and inexpensive.

FIG. 2 is a block diagram showing an embodiment of the switching device of the present invention. In FIG. 2, the switching device TSWa corresponds to the switching device TSWa shown in FIG. Lines L1, L2, and L3 are each paired, and one of the lines L1 is connected to terminals α ₁ and α ₂ ,
The other is connected to the subscriber line SL. One side of line L2 is connected to terminals β ₁ and β ₂ , and the other side is connected to switch SW
connected to. One side of the line L3 is connected to the terminals γ ₁ and γ ₂ , and the other side is connected to the telemetering device TMR. Signal detector DETa is connected to line L2, and signal detector DETb' is connected to line L1.
When the signal detector DET does not detect a switching signal, the terminals α and γ are connected. The switching output of each signal detector DET is input to an OR circuit OR, and when a switching signal is detected in any of the signal detectors DET, the connection is switched between terminal α and terminal β.

The example shown here is a configuration that detects the 16Hz ringing signal (TR) and direct current loop (DCL) of a telephone call, but the signals to be detected are not limited to these, and the carrier frequency of the data communication signal, Specific dial signals such as button dial signals and various other signals generated in conjunction with communication signals can be targeted.

Next, an embodiment of the communication line switching device of the present invention will be described.

Figure 3 shows the subscriber line SL at the telephone office
FIG. 3 is a diagram showing an example of the configuration of a main distribution board MDF connected to SW.

The subscriber line SL is connected to one terminal pair 1 of the terminal board 10.
1 ₁ , 11 ₂ , and the terminal pair 11 ₁ , 11 ₂ is connected to the other terminal pair 15 via the disconnection contact pair 13 ₁ , 13 ₂ .
₁ , 15 ₂ , and the terminal pair 15 ₁ , 15 ₂ is connected to one terminal pair 21 of the terminal board 20 via jumper wire J.
The terminal pair _{21 1} , 21 ₂ is connected to the other terminal pair 25 ₁ , 25 _{2 ,} and the terminal pair 25 ₁ , 21 _{2 is connected to the other terminal pair 25 1 , 25 2 .}
25 Switch SW is connected to ₂ . A trunk line TL is connected to the exchange SW.

The disconnection contact pair 13 ₁ , 13 ₂ is used to disconnect the subscriber line SL from the exchange SW for _the purpose of testing and inspection.
3 Insert the switching device TSW of the present invention into ₂ .

FIG. 4 is a diagram showing an overview of the main parts of the pair of disconnecting contacts and the switching device. 4a is a pair of disconnecting contacts, FIG. 4b is a switching device, and FIG. 4c is a partial sectional view of the pair of disconnecting contacts and the switching device.

In FIG. 4, reference number 10 is a terminal board, reference numbers 11 ₁ and 11 ₂ are contact pieces of one pair of terminals, reference numbers 15 ₁ and 15 ₂ are contact pieces of the other pair of terminals, Reference numbers 13 ₁ and 13 ₂ indicate insertion holes for a pair of disconnecting contacts. Reference numbers 31 ₁ and 31 ₂ are contact pieces connected to terminals α ₁ and α ₂ of the switching device TSW, and reference numbers 32 ₁ and 32 ₂ are contact pieces connected to terminal β. Reference numbers 33 ₁ and 33 ₂ are protrusions for insulating the contact pieces 31 and 32 and inserting them into the separation contact pair 13. Reference numbers 34 ₁ and 34 ₂ are contact pieces connected to the terminals γ ₁ and γ ₂ .

In this way, the switching device TSW is disconnected from the contact pair 13.
It can be easily implemented by creating a structure that can be inserted into the system. That is, by inserting the protrusion 33 into the pair of disconnecting contacts 13, electrical continuity is established between the contact piece 11 and the contact piece 31, and between the contact piece 15 and the contact piece 32, and the connection between the subscriber line SL and the exchange SW is established. The switching device of the present invention can be electrically inserted between the two and mechanically fixed at the same time. Subscriber line SL and contact piece 1 soldered to contact pieces 11 and 12
Mounting can be easily performed without any modification to the jumper wires J soldered to 5 and 16.

FIG. 5 is a diagram showing an arrangement row of switching devices of the present invention mounted on a distribution board of a private branch exchange, FIG. 5a shows an example of the configuration of the distribution board, and FIG. show.

In FIG. 5, reference number 40 is a drop-in line, reference number 50 is a premises line, and reference number 6
0 is a terminal board to which the drop-in line 40 is connected through a terminal pair 61 ₁ , 61 ₂ , and reference numeral 70 is a terminal board to which the local line 50 is connected through a terminal pair 71 ₁ , 71 ₂ . A terminal pair 62 ₁ , 62 ₂ connected to the terminal pair 61 ₁ , 61 ₂ of the terminal board 60 and a terminal pair 72 ₁ , _{7 connected to the terminal pair 71 1 , 71 2 of} the terminal board 70
2 and ₂ are connected by a jumper wire J. Switching device TSW of the present invention arranged in this private branch exchange
are terminal pieces 81 ₁ and 82 ₂ connected to terminals β ₁ and β ₂
are connected to the terminal pair 62 ₁ , 62 ₂ of the terminal board 60, and the terminal pieces 82 ₁ , 82 ₂ are connected to the terminals α ₁ , α ₂
The configuration is such that jumper wire J is connected to. Reference numbers 83 ₁ and 83 ₂ are branched terminal pieces connected to the terminals γ ₁ and γ ₂ .

In this way, the terminal pieces 81 ₁ and 81 ₂ of the switching device TSW are screwed to the terminal pair 62 ₁ and 62 ₂ to which the jumper wire J is screwed, and the jumper wire J is screwed to the terminal pieces 82 ₁ and 82 _2. By fastening, the switching device TSW can be electrically inserted between the jumper wire J and the terminal board 60 and mechanically fixed at the same time. That is, the switching device TSW can be easily mounted without removing the lead-in line 40 that is normally soldered to the terminal board 60.

Here, the driver insertion hole 84 is a hole for turning the screw of the terminal 62 ₂ of the terminal board 60, and if necessary, the inside of the hole is insulated so that the terminal pieces 81 ₁ and 81 ₂ do not conduct when inserting the metal driver. may be applied.

In this embodiment, the switching device TSW is connected to the terminal board 6.
0 and the jumper wire J, but the same effect can be obtained by inserting the wire between the jumper wire J and the terminal board 70.

〔Effect of the invention〕

As explained above, the present invention is a method in which a communication signal with the lowest priority is normally transmitted between two points, and when a communication signal with a higher priority arrives, it can be automatically interrupted. Therefore, the signal detection means only needs to detect the signal transmitted along with the communication signal, which simplifies the structure of the switching device and greatly simplifies the control method.

Therefore, it is possible to multiplex communication lines easily and at low cost, and it is easy to use the idle time of transmission of the main communication signal to use the slave communication signal. This has the advantage of being able to provide additional services (telemetry, safety monitoring, data communications, etc.) at low cost.

Furthermore, the switching device can be easily installed by having a structure that allows it to be inserted into a pair of disconnecting contacts on a terminal board in a telephone office, and a structure that allows it to be inserted between a jumper wire and a terminal board in a private branch exchange.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a communication line multiplexing device in which the switching device of the present invention is used. FIG. 2 is a block diagram showing an embodiment of the switching device of the present invention. Figure 3 shows the subscriber line SL at the telephone office
A diagram showing an example of the configuration of the main distribution board MDF connected to SW.
FIG. 4 is a diagram showing an overview of the main parts of the pair of disconnecting contacts and the switching device. FIG. 5 is a diagram showing an example of the arrangement of the switching device of the present invention mounted on a distribution board of a private branch exchange. A...Telephone office, B...Subscriber's premises, TSWa,
TSWb...Switching device of the present invention, TMRa, TMRb
... Telemetering device, SW ... Switching machine, SL
...Subscriber line, TE...Telephone, DETa, DETb
...Signal detector.

Claims (1)

[Claims] 1. A state in which a communication signal passes between a first terminal and a second terminal through which one communication line is connected between two points and multiple types of communication signals are transmitted in a time-sharing manner. and a switching circuit that switches and connects a state in which a communication signal passes between the first terminal and the third terminal, and a control circuit that controls the switching circuit. a first signal detector that detects that a communication signal arrives at a first terminal; a second signal detector that detects that a communication signal arrives at a second terminal; an OR circuit that receives each detection output of the signal detector as input, and when the OR circuit has an OR output, a communication signal passes through the switching circuit between the first terminal and the second terminal. The communication line switching device is configured to set the switching circuit to a state in which a communication signal passes between a first terminal and a third terminal when the logic sum circuit does not have a logic sum output. 2. Either the first signal detector or the second signal detector includes a circuit that detects the arrival of a telephone call signal at the first terminal, and the first signal detector or the second signal detector The communication line switching device according to claim 1, wherein the other of the terminals includes a circuit that detects that the DC loop of the second terminal is closed. 3. The communication line switching device according to claim 1, wherein the first and second signal detectors include a circuit that detects a carrier wave of a data transmission signal. 4 The first terminal and the second terminal are formed by metal plates on both sides of one terminal board separated by an insulating material, and this terminal board is installed in the main distribution frame (MDF) of the subscriber line.
The communication line switching device according to claim 1, which has a structure that can be inserted into a test terminal. 5. The communication line switching device according to claim 1, wherein the first terminal and the second terminal have a structure that can be connected to a main distribution frame (MDF) of the subscriber line by screwing.