JPH0583750A - Telephone exchange system - Google Patents

Abstract

PURPOSE:To prevent destruction of an IC due to voltage impression to an IC in the inside of a telephone set to which power supply from a battery is stopped or due to a system error by preventing the mixed existence of a telephone set to which power supply from a battery is stopped and a telephone set to which power supply from a battery continues. CONSTITUTION:When a power failure detection circuit 22b detects a power failure of a battery 10b at a power failure of an AC power supply, a control relay 23b is closed. Then since no DC current flows through a control line, contacts of battery feeding relays 21a, 21b, 21c are opened and power supply from batteries 10a, 10b, 10c is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a telephone exchange system, and more particularly to a telephone exchange system having a structure called, for example, a building block system, which is formed by connecting a plurality of telephone devices each having a battery as a backup power source. ..

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing an example of a conventional telephone exchange system of this type. The telephone exchange system shown in FIG. 2 is basically a key telephone device 1
(Hereinafter referred to as "basic rack 1") and button telephone devices 2 and 3 for expansion (hereinafter referred to as expansion rack 2 and expansion rack 3)
And 3 button telephone devices (hereinafter referred to as "the rack"). The internal structure of the basic rack 1 and the internal structures of the expansion racks 2 and 3 are the same as shown in the figure, and the expansion racks 2 and 3 are stacked on the basic rack 1. The control signal transmission line 5 and the PC are connected between the racks 1, 2 and 3.
They are connected to each other by the M signal transmission line 6.

As described above, since the internal configurations of the extension rack 2 and the extension rack 3 are the same as those of the basic rack 1, the respective parts of the extension rack 2 and the expansion rack 3 are the same as those of the basic rack 1. The same parts are denoted by the same reference numerals with different subscripts, and the explanation of the operation of each part in the extension racks 2 and 3 is omitted.

In FIG. 2, when the AC power source (not shown) is not out of power and a predetermined AC voltage is supplied, the AC power source (not shown) changes the AC power cord 9a of the basic rack 1 to the power transformer. The AC voltage supplied to the AC / DC regulator 12a via 11a is the AC / DC regulator 12a.
The DC voltage is converted by the regulator 12a. This D
The C voltage is supplied from the AC / DC regulator 12a to the power supply unit 7 together with the AC / DC regulator 12a.
It is applied to the DC / DC converter 14a and the battery control circuit 13a which constitute a. The DC voltage input to the DC / DC converter 14a is converted by the DC / DC converter 14a into a predetermined DC voltage necessary for operating the interface 8a, and then the control unit 17a that constitutes the interface unit 8a and It is output to the communication unit 15a, respectively.

As mentioned above, an AC power source (not shown)
Is in a normal state and is supplying a predetermined AC voltage, D output from the AC / DC regulator 12a
The C voltage should exceed the preset blackout threshold. Therefore, the battery control circuit 13a is
When the output DC voltage exceeds the power failure threshold value, the DC voltage from the external battery 10a is cut off. On the other hand, if the output DC voltage is less than the power failure threshold value, the battery control circuit 13a
Is the DC output from the external battery 10a.
The voltage is supplied to the DC / DC converter 14a. DC
The DC voltage input to the / DC converter 14a is converted into a predetermined DC voltage required for operating the interface unit 8a by the DC / DC converter 14a, as described above. This DC voltage is output to the control unit 17a and the call unit 15a, respectively. The battery control circuit 13a constantly monitors the output voltage of the external battery 10a described above, and when it detects that the output voltage of the battery 10a is less than a preset threshold voltage, ,
DC / DC converter 14a from the battery 10a
Supply of DC voltage to

The control unit 17a is driven by a predetermined DC voltage supplied from the DC / DC converter 14a, controls not only the communication unit 15a but also the control unit 17b of the extension rack 2 through the control signal transmission line 5. , Exchanges various control information with the control unit 17c of the extension rack 3.

The call unit 15a, under the control of the control unit 17a described above, has the DC / DC converter 14a.
It is driven by a predetermined DC voltage supplied from a. For example, a time division exchange connection between the office line 18a and the telephone 16a, a telephone 16b connected to the call unit 15b of the extension rack 2, and the telephone 16a. Perform time-division exchange connection, etc. Then, a communication path between the office line 18a and the telephone 16a and a communication path between the telephone 16b and the telephone 18a are formed through the PCM signal transmission line 6. In FIG. 2, only one telephone is connected to each call unit of each rack, but in reality, a plurality of telephones are connected to each rack.

[0008]

By the way, in the conventional telephone exchange system having the above structure, the batteries 10a, 1
If the amount of charge accumulated in each of the batteries 10a, 10b, 10c is different at the time of backup power supply by 0b, 10c, the output voltage of each of the batteries 10a, 10b, 10c may fall below the threshold value. There is a difference.
Therefore, the battery control circuit of each rack also has different time for stopping the power supply from the corresponding battery.

As described above, if the time during which the power supply from the battery is stopped differs depending on each rack, various problems will occur as described below.

For example, between the telephone set 16a connected to the basic rack 1 and the telephone set 16b connected to the extension rack 2 via the respective communication units 15a and 15b and the PCM signal transmission line 6, If the power supply from the battery 10a in the basic rack 1 is stopped first while the speakers of the two telephones are making an extension call, the telephone 16a is disconnected from the driving power source.
Since the person a is completely inoperable, the speaker of the telephone 16a can recognize that the driving power supply is cut off. However, on the other hand, in the extension rack 2, since the power supply from the battery 10b is still continued, both the control unit 17b and the call unit 15b are in the driving state. That is, the control unit 17b is in a state where it can exchange various control information with the control unit 17a of the basic rack 1, and the call unit 15b exchanges PCM data with the call unit 15a of the basic rack 1. Therefore, the speaker of the telephone 16b may erroneously think that the cause of the sudden disconnection of the extension call is a malfunction or an erroneous operation of the other party. Not only that, even if one rack is not driven, the telephone exchange system as a whole is in a driving state. Therefore, for example, when an incoming call signal is received from the station line 18b to the telephone 16a, control is performed. The unit 17b is
In order to connect the station line 18b and the communication device 16a, the control unit 17 is operated even though the basic rack 1 is stopped.
There is also a problem that the exchange operation is executed between the a and the call unit 15a.

That is, the software contained in the control unit of each rack is constructed on the assumption that all the racks constituting the telephone exchange system are operating normally. If such a situation occurs, an unexpected situation will occur in software, and an unexpected error will occur, possibly leading to a system down.

Further, each of the above-mentioned interface units 8
When the ICs are used for a, 8b, and 8c, for example, as described above, when the power supply from only the basic rack 1 is stopped from the battery 10a, the interface units 8b and 8c of the extension racks 2 and 3 where the power supply is continued. Since the signal voltage is applied to the interface unit 8a to which the power supply voltage is not applied from the control signal transmission line 5 or the PCM signal transmission line 6, there is a risk that the IC configuring the interface unit 8a is damaged. There was also.

Therefore, the present invention has been made in consideration of the above circumstances, and an object thereof is to prevent a telephone device in which power supply from a battery is stopped and a telephone device in which power supply from a battery is continued from being mixed. As a result, it is possible to provide a telephone exchange system in which there is no possibility that an error will occur in the system or the IC will be damaged by the voltage application to the IC provided inside the telephone device whose power supply from the battery is stopped. is there.

[0014]

In order to achieve the above-mentioned object, the present invention is to connect a plurality of telephone devices each of which keeps its own driving state by the power supply from a built-in battery when the commercial power source fails. In the telephone exchange system formed as described above, a battery power failure detection unit that detects that each of the batteries has a power failure, and a battery power failure detection unit that remains when the battery power failure detection unit detects that one of the batteries has a power failure Power supply stopping means for stopping power supply from the battery to the corresponding telephone device.

[0015]

In the above structure, when the commercial power supply fails, each battery starts supplying power to the corresponding telephone device in order to back up the corresponding telephone device.
At this time, if any one of the batteries has a power failure, this power failure is detected by the battery power failure detection means. When the battery power failure detection means notifies the power failure detection, the power supply stopping means immediately stops the power supply from the other battery to the corresponding telephone device based on the notification. As a result, it is possible to prevent the telephone device in which the power supply from the battery is stopped and the telephone device in which the power supply from the battery is continued from being mixed, and an error occurs in the system or the telephone device in which the power supply from the battery is stopped. It is possible to solve the problem that the IC is damaged due to the voltage application to the IC provided inside the IC.

[0016]

DETAILED 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 an overall configuration of a telephone exchange system according to an embodiment of the present invention. The telephone exchange system shown in FIG. 1 is similar to the above-described conventional telephone exchange system, but includes a basic rack 101 and extension racks 102, 1
It is equipped with three racks with 03. Explaining the telephone exchange system again, the extension rack 1 is mounted on the base rack 101.
02, 103 are stacked, and the control signal transmission line 5 is provided between the racks 101, 102, 103.
The PCM signal transmission line 6 and the control line 25 are connected to each other.

As is apparent from FIG. 1, the basic rack 101 and the expansion racks 102 and 103 have substantially the same internal structure. That is, the basic rack 101 and the expansion racks 102 and 103
Includes power supply units 107a, 107b, 107c and interface units 8a, 8b, 8c, respectively. Each power supply unit 107a, 107b, 107c
Starting with the power transformers 11a, 11b and 11c,
C / DC regulators 12a, 12b, 12c, battery power supply relays 21a, 21b, 21c, mainly these battery power supply relays 21a, 21b, 21c
Battery control circuits 13a, 13b, 13 for controlling the
c, DC / DC converters 14a, 14b, 14c, and power failure detection circuits 22a, 22b, 22c. However, while control relays 23b and 23c (both are normally closed contacts) are provided on the extension racks 102 and 103, respectively, the basic rack 101 has a current limiting resistor 24 instead of the control relay. In terms of being provided, the basic rack 101
And the extension racks 102 and 103 are different.

As described above, the internal configurations of the extension rack 102 and the extension rack 103 and the internal configuration of the basic rack 101 are substantially the same, and moreover, these internal configurations and the basic rack shown in FIG. 1. Since the internal configurations of the extension racks 2 and 3 are substantially the same, the same parts as those shown in FIG. 2 are the same as those used in FIG. 2 for each part shown in FIG. It is decided to attach a reference numeral.

In FIG. 1, when the AC power supply (not shown) is not out of power and a predetermined AC voltage is supplied, the AC voltage supplied from the AC power supply (not shown) is the basic rack 101. Is supplied to the AC / DC regulator 12a through the AC power cord 9a and the power transformer 11a. The AC voltage is the AC / DC regulator 1
It is converted into a DC voltage at 2a. This DC voltage is applied not only from the AC / DC regulator 12a to the DC / DC converter 14a and the power failure detection circuit 22a but also to both ends of the control line 25 described above. That is, the DC current generated by applying the DC voltage is AC / D
C regulator 12a to control relay 23b (normally closed contact), control relay 23c (normally closed contact), coil of battery power supply relay 21c, battery power supply relay 21
It is supplied to the circuit formed via the coil b, the coil of the battery power supply relay 21a, and the current limiting resistor 24. When a DC current flows through the circuit, the coils of the battery power supply relays 21a, 21b, 21c are excited, and the battery power supply relays 21a, 2c are respectively excited.
The normally open contacts 1b and 21c are closed.

The DC voltage input to the DC / DC converter 14a is converted into a predetermined DC voltage required for operating the interface unit 8a by the DC / DC converter 14a, and then the interface unit 8 is operated.
control unit 17a and call unit 15 that compose a
It is output to a respectively.

The control unit 17a is driven by a predetermined DC voltage supplied from the DC / DC converter 14a, not only controls the communication unit 15a but also controls the extension unit 102 through the control signal transmission line 5. , And exchanges various control information with the control unit 17c of the extension rack 103.

The call unit 15a is controlled by the control unit 17a described above, and the DC / DC converter 14 is operated.
It is driven by a predetermined DC voltage supplied from a. For example, a time-division exchange connection between the office line 18a and the telephone 16a, a telephone 16b connected to the call unit 15b of the extension 102, and the telephone 16a. Perform time-division exchange connection, etc. Then, a communication path between the office line 18a and the telephone 16a and a communication path between the telephone 16b and the telephone 18a are formed through the PCM signal transmission line 6. In FIG. 1, only one telephone is connected to each call unit of each rack, but in reality, a plurality of telephones are connected to each rack.

As mentioned above, an AC power source (not shown)
Is in a normal state and is supplying a predetermined AC voltage, D output from the AC / DC regulator 12a
The C voltage should exceed the preset blackout threshold. Therefore, D by the power failure detection circuit 22a
The value of the voltage signal output from the power failure detection circuit 22a to the battery control circuit 13a based on the detection of the C current is a value exceeding the power failure threshold value. Therefore, the battery control circuit 13a forcibly opens the normally open contact of the battery feeding relay 21a which has been closed so as to cut off the DC voltage feeding from the external battery 10a.

On the other hand, when the value of the voltage signal output from the power failure detection circuit 22a is less than the power failure threshold value, the battery control circuit 13a closes the normally opened contact that has been forced to perform the opening operation. Thus, the DC voltage output from the external battery 10a is supplied to the DC / DC converter 14a. The DC voltage input to the DC / DC converter 14a is converted into a predetermined DC voltage necessary for operating the interface unit 8a by the DC / DC converter 14a, as described above. This DC voltage is applied to the control unit 17a and the call unit 1
5a, respectively.

At the time of power failure of the AC power source (not shown),
When recognizing that the voltage signal output from the power failure detection circuit 22a has fallen below a preset battery power failure threshold value, the battery control circuit 13a causes the battery power supply relay 21a in the closed state to have a normally open contact. Is forcibly opened, and D from the external battery 10a is
Cut off the C voltage supply. As a result, the DC current is prevented from flowing into the control line 25, the coils of the battery power supply relays 21b and 21c are demagnetized, and the corresponding normally open contacts are opened. Therefore, the power supply from the external battery 10b of the extension rack 102 and the power supply from the external battery 10c of the extension rack 103 are performed by the battery control circuit 1 described above.
The power is cut off substantially in synchronism with the power cutoff by 3a.

Next, the operation of the extension rack 102 will be described. As described above, when the AC power supply (not shown) is in the normal state and the predetermined AC voltage is supplied, A
The DC voltage output from the C / DC regulator 12b should exceed the preset power failure threshold value as described above. Therefore, the power failure detection circuit 22
Based on the detection of the DC current by b, the power failure detection circuit 22
The value of the voltage signal output from b to the battery control circuit 13b is a value exceeding the power failure threshold value. Therefore, the battery control circuit 13b forces the normally open contact of the battery power supply relay 21b being closed by exciting the corresponding coil as described above in order to cut off the power supply of the DC voltage from the external battery 10b. Open it up.

On the other hand, if the value of the voltage signal output from the power failure detection circuit 22b is less than the power failure threshold value, the battery control circuit 13b closes the normally open contact that has been forced to perform the opening operation. Thus, the DC voltage output from the external battery 10b is supplied to the DC / DC converter 14b. The DC voltage input to the DC / DC converter 14b is converted into a predetermined DC voltage required for operating the interface unit 8b by the DC / DC converter 14b, as described above. This DC voltage is applied to the control unit 17b and the communication unit 1
5b will be output respectively.

At the time of power failure of the AC power source (not shown),
When recognizing that the voltage signal output from the power failure detection circuit 22b has fallen below a preset battery power failure threshold value, the battery control circuit 13b causes the control relay 23b (normally closed contact) in the closed state to operate. It is opened to prevent the DC current supplied from the basic rack 101 side from flowing into the control line 25. This allows the battery power supply relay 2
The coils 1a, 21b and 21c are demagnetized and the corresponding normally open contacts are opened. Therefore, the power supply from the external battery 10a of the basic rack 101 and the power supply from the external battery 10c of the extension rack 103 are cut off substantially in synchronization with the cutoff of the power supply by the battery control circuit 13b. The operation of the extension rack 103 is the same as the operation of the extension rack 102 described above, and a description thereof will be omitted.

As described above, according to the embodiment of the present invention, the batteries 10a, 10b and 10c externally attached to the base rack 101 and the extension racks 102 and 103, respectively.
When the corresponding power failure detection circuit (22a, 22b, 22c) detects that the power supply is stopped from any of the
Since it is possible to stop the power supply from the batteries of other racks almost in synchronism with the stop of the above power supply, it is possible to prevent the rack from which the power supply from the battery is stopped and the rack from which the power supply from the battery is continuing to be mixed. This makes it possible to prevent a system error and IC damage due to voltage application to the IC inside the rack where power supply from the battery is stopped.

It should be noted that the above content is merely an example according to the present invention, and does not mean that the present invention is limited to the above content. For example, in the above embodiment, the DC current flowing through the control line 25 is applied to the basic rack 10
1 is supplied, but the control line 25 is supplied from the extension racks 102 and 103 instead of the basic rack 101.
The connection of may be changed. In addition, power failure detection circuits 22a-2
Although the circuit for detecting the DC current flowing between the AC / DC regulator and the DC / DC converter is used for 2c, the circuit for detecting the DC voltage applied to the input side of the DC / DC converter is used. Does not matter. Furthermore, a semiconductor switching element such as a transistor or a photo coupler may be used instead of the battery power supply relay or the control relay. Further, in the above embodiment, the telephone exchange system having two extension racks has been described, but the present invention can be naturally applied to a telephone exchange system having three or more extension racks.

[0032]

As described above, according to the present invention,
Battery power failure detection means for detecting a power failure of the battery built in each telephone device, and from the remaining batteries when the battery power failure detection means detects that one of the batteries has a power failure. Since the power supply stopping means for stopping power supply to the corresponding telephone device of No. 1 is provided, it is possible to prevent the telephone device in which the power supply from the battery is stopped and the telephone device in which the power supply from the battery is continued from being mixed. As a result, it is possible to provide a telephone exchange system in which there is no possibility that an error will occur in the system or the IC will be damaged by the voltage application to the IC provided inside the telephone device in which the power supply from the battery is stopped. ..

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a telephone exchange system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an overall configuration of a telephone exchange system according to a conventional technique.

[Explanation of symbols]

 9a, 9b, 9c AC power cord 10a, 10b, 10c Battery 13a, 13b, 13c Battery control circuit 21a, 21b, 21c Battery power supply relay 22a, 22b, 22c Power failure detection circuit 25 Control line 101, 102, 103 Telephone device

Claims (2)

[Claims] 1. A telephone exchange system in which a plurality of telephone devices, each of which keeps its own driving state, is connected to each other by a power supply from a built-in battery when a commercial power source is cut off. A battery power failure detecting means for detecting that a power failure is detected, and when the battery power failure detecting means detects that one of the batteries has a power failure, a power stopping means for stopping power supply from the remaining battery to the corresponding telephone device. And a telephone exchange system. 2. The telephone exchange system according to claim 1, wherein the battery power failure detection means is provided corresponding to each of the telephone devices, and each battery power failure detection means operates in response to a power failure of a commercial power source. A telephone exchange system characterized by detecting the power outage of each battery by detecting the output of the battery.