JPS60171894A - Decentralized key telephone controller - Google Patents

Abstract

PURPOSE:To attain ease of installation of a telephone set or extension of trunk line/extension line by connecting plural control units having the same function with a common control bus, common trunk line trunk and a common extension mutural trunk. CONSTITUTION:Trunk lines 1a, 1b, 1c, a trunk line common trunk 2, an extension mutual trunk 3, a control bus 4, an extension 6 and an extension telephone set 7 are connected to control units 5a, 5b, 5c. When a incoming comes from the trunk 1b, a telephone set 10 is hooked off by a call tone and the call is responded. In transferring the call to an extension telephone set connected to other extension telephone set, e.g., the control unit 5a, a transfer button 15 is depressed, a transfer request code signal is transmitted to the control unit 5b covered by the own set, then the control unit 5a is selected by four extension group selection button 11 of A-D and the call is transferred to a desired extension telephone set of the control unit 5a by depressing an extension number by a ten-key 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a control device for a key telephone system.

(Technical background) Conventionally, in the key telephone system, telephones are distributed, and no matter which telephone you use, you can make a call, receive an incoming call, or receive a call from any telephone.
There is a function to forward incoming calls to another phone.

Although this system is only for efficient use of a plurality of telephones, the control device is usually installed at one location, from which speech lines and control lines are connected to each telephone. For this reason, the wiring to each telephone was long, and construction work for installing and moving the telephones was very troublesome. In addition, since the maximum number of station lines and maximum extension lines are fixed for each type, there was a drawback that if the number of station lines or extensions increased, all the control equipment and telephones had to be replaced. .

(Object of the Invention) In view of the above-mentioned drawbacks, the object of the present invention is to distribute the control device of a key telephone system into several units and configure a key telephone system of any size by connecting these units. The purpose of this invention is to obtain a new key telephone control device, which will be explained in detail below using an embodiment.

(Structure of the Invention) The present invention uses a key telephone system that is composed of a plurality of control units having substantially the same functions, and each control unit is connected to a common control bus, a common office line trunk, and a common office line trunk. This distributed key telephone control device is characterized in that it is connected to mutual extension trunks, and will be described in detail below using an embodiment.

(Example) FIG. 1 shows a relatively small-scale embodiment of the invention.

In the figure, 1a, 1b, and IC are office lines, 2 is a trunk common to the office line, 3 is a mutual extension trunk, 4 is a control bus, and 5a, 5b.
, 5c is a control unit, 6 is an extension, and 7 is an extension telephone.

In this embodiment, three control units having two central office lines and four extension lines and having the same configuration are used, and between each control unit there is a pair of control buses, two mutual trunk trunk lines, It is connected by 8 common trunk lines.

The number of control units is installed as required depending on the scale of the extension line and the scale of the office line, but in this example, there are 8 common trunks for the office line.
Since one control unit is in charge of two lines, a maximum of 4 control units can be connected.

Next, the operation of the extension telephone according to this embodiment will be explained using the telephone shown in FIG. It is assumed that this telephone is connected to the control unit 5b in Fig. 1.O First, when there is an incoming call from the central office line, for example 1b, the ring tone will sound on all extension telephones at the same time, so the telephone shown in Fig. 2 The user then picks up the handset 10 and picks up the hook to form a telephone loop and respond.

If you want to transfer this call to another telephone extension, for example a telephone extension connected to the control unit 5a, press the transfer button 15.
Press to send a transfer request code signal, for example represented by 4 bits, to the control unit 5b in charge of itself, and
Next, by selecting the control unit 5a with the four extension group selection buttons 11 on A-D-t and then pressing the extension number with the numeric keypad 12, the call is transferred to the desired extension telephone connected to the control unit 5a. be able to.

Also, in the case of an extension call, as in the case of transfer, the extension button 14 is pressed to send an extension call request code signal represented by, for example, 4 bits to the control unit 5b, and then the extension group selection button 11 and the numeric keypad are pressed. By pressing the 12 button, the desired telephone extension can be called.

Furthermore, when making a call from the main extension telephone to another telephone via a central office line, the call button 13 is pressed to send a call request code signal expressed in 4 bits as described above to the control unit 5b, and then By pressing a dial number on the numeric keypad 12, it is possible to connect to a desired outside telephone.

Next, the mutual operation between each control unit to realize the operation of the extension telephone described above is shown in FIGS. 1, 3, and 4.
This will be explained using figures.

FIG. 3 is an explanatory diagram showing the inside of the control unit in detail in order to explain the operation of the control unit.
b is used. In the figure, 20 is a switching circuit, 21 is a circuit for receiving a central office line, 22 is a conversion circuit for outgoing dialing and a signal sending circuit for receiving a central office line, 23 is a central office line trunk incoming signal detection circuit, and 24 is an extension mutual trunk. 25 is a monitoring circuit, 25 is an extension control circuit, 26 is a central control unit including a μ processor, 27 is a serial conversion transmitting/receiving circuit for a control bus, and 28 is a communication path intersection transistor.

In this embodiment, in order to exchange information such as connection requests and line reservations between the control units, a common control bus 4 is provided between each control unit, and a high-speed asynchronous Perform data communication.

Therefore, when communicating with another control unit via the control bus 4, the central control unit 26 determines whether or not the control bus 4 is free by detecting the carrier, and determines whether or not the control bus 4 is free. Send data only if In addition, poor reception caused by collision with data from other control units, etc. is monitored by the central control unit 26, and if a poor reception occurs, the previously sent data is
Retransmit within a specified time such as 5m5.

First, the case where a call is made from an extension telephone to a central office line will be explained. As described above, when making a call from an extension telephone connected to the control unit 5b to a central office line, for example, a call request code signal is sent from the originating extension telephone via the extension 6 to the control unit 5b.

On the other hand, on the control unit 5b side, the extension control circuit 25 detects the call request code signal and notifies the central control section 26 of the call request code signal. The central control section 26 that received the notification sends the control unit 5
Check to see if there is a vacancy on either of the office lines 1b of ``b'', and if there is a vacancy, specify that office line, switch the switching circuit 2o to the conversion circuit 22 for outgoing dialing, and switch between the central office lines and Connect the extension telephone that requested the call.

If there is no vacancy, a 12-bit office line call request signal shown in FIG. 4 is sent to another control unit, for example 5a, via the control bus 4.

The control unit 5a has the same configuration as the control unit 5b, and the central control section corresponding to FIG. A 12-bit answer signal shown in FIG. 4 is sent back to the control unit 5b. The sixth bit of the answer signal is set to 1 if there is a vacant line on the central office line 1a, and is set to 0 if there is no vacant line.

When the control unit l-5b receives an answer signal with the sixth bit set to 0, it sends the central line call request signal again to another control unit, for example, the control unit 5c shown in FIG. do.

Then, if all the office lines of all the control units, for example, controls 22) 5a and 5e in FIG. 1, are not available, the control unit 5b sends an all-busy signal to the extension telephone that requested the call. On the extension telephone side, in addition to the all-busy signal, for example, a signal tone or a lamp is used to indicate that there is no vacancy on any central office line.

If the control unit requested to connect to the central office line, e.g.
If the office line 1a of a is vacant, the 6th bit is set to 1, the 7th bit specifies either the office line Ja, and a reply signal is sent back, and the control unit 5a, corresponding to Fig. 3 26, is sent back. The central control unit switches the switching circuit corresponding to FIG. 3 20 of the specified office line to the calling dial conversion circuit corresponding to FIG. 3 22.

Then, the control unit 5b that received the reply signal,
A connection is made to the control unit 5a via the central office line common trunk 2, and the connection between the own extension telephone and the central office line Ja is completed.

Next, a case where a call is received from the central office line 1b will be explained.

When the control unit 5b is waiting for an incoming call, the switching circuit 20 is connected to the office line receiving circuit 21, so that when an incoming call is received, it is detected by the office line receiving circuit 21 and the central control unit 26 is notified. The notified central control unit 26 switches the switching circuit 20
22, and sends out a 1700 Hz office line trunk arrival signal via the office line common trunk 2 to each control unit including itself.

Each control unit monitors the common trunk for each office line using the office line trunk incoming signal detection circuit equivalent to Fig. 3, 23, so when it detects the office line trunk incoming signal, each of the four control units assigned to it A ringing signal is sent to the telephone extension of the telephone, and a ringing tone is generated all at once. First, hang up the handset and connect to the extension telephone set on the hook. If the control unit that made the connection is 5a, for example, 5a
The internal central control unit corresponding to FIG. 326 selects the central office line common trunk through which the central office line trunk incoming signal is flowing by the central office line trunk incoming signal detection circuit equivalent to FIG. Make a connection with On the other hand, control unit 5
When the connection is made in b, the transmission of the office line trunk incoming signal is stopped, and the connection between the office line 1b where the call was received and the office line common trunk is completed.

Next, a case of transferring a call will be explained. As mentioned above, when transferring a call in an extension telephone connected to the control unit 5b, for example, a call request code signal is sent to the control unit 5b, so the extension control circuit 25 receives the call request code. The signal is detected and notified to the central control unit 26.

The central control unit 26 that has received the notification sends a 12-bit timing signal shown in FIG. 4 to the destination control unit, for example 5C, via the control bus 4. The control unit 5C that received the timing signal receives the sixth . It determines whether or not its own extension designated by the 7th bit is vacant, and returns the 12-bit answer signal described above.

The 6th bit of the answer signal is set to 1 if the aforementioned extension is free, and O is set if it is not.The control unit 5b that received the answer signal determines the 6th bit, and if the extension is 0, then O is set. A busy signal is sent to the transfer source extension telephone to notify that the call is in progress, and if it is 1, a transfer request signal shown in FIG. 4 is returned.

6th of the transfer request signal. 7th. The 8th bit specifies the central office line common trunk to be used for transfer, and the control unit 5b connects the call to the central office line common trunk immediately after sending the transfer request signal, so that the control unit 5b of the transfer destination 5C receives the transfer request signal and simply connects the specified office line common trunk to the specified extension, and the call is transferred to its own extension telephone.

Furthermore, a case where mutual extension calls are made will be explained.

As mentioned above, for example, when a call is made from an extension telephone connected to the control unit 5b and an extension telephone is connected to the control unit 5C, the extension call request code signal is first sent from the extension telephone of the originator. Since it is sent,
The extension control circuit 25 of the control unit 5b detects the extension call request code signal, and the control section 26 sends a 12-bit timing signal shown in FIG. 4 to the control unit 5c via the control bus 4.

The control unit 5c that received the nuclear alignment signal receives the sixth. It checks whether or not its own extension designated by the seventh bit is vacant, and returns the answer signal shown in FIG. 4.

The sixth bit of the answer signal is set to 1 if there is a vacancy in the designated extension, and is set to O if there is no vacancy. Furthermore, when the sixth bit is set to 1, the eighth bit specifies which of the mutual extension trunks 3 should be used for the call.

Therefore, the control unit 5b that received the reply signal,
The 6th bit of the response signal is determined, and if it is 0, a busy signal is sent to the extension telephone that requested the inter-extension call, and if it is 1, the 6th bit is sent after connecting the extension telephone and the specified inter-extension trunk. A 12-bit extension mutual request signal shown in FIG. 4 is sent to the control unit 5c. Then, the control unit 5C that received the extension mutual request signal connects its own extension telephone specified by the above-mentioned delay signal and the extension mutual trunk specified by itself by the above-mentioned answer signal, and establishes an extension mutual communication path. It forms.

As described above, in this embodiment, each control unit has the same function and operates by communicating with each other. Therefore, when adding telephones, or increasing the number of office lines or extension lines, it is necessary to add each control unit individually or The advantage is that all you have to do is change the internal program, and there is no need to replace all telephones and control devices as in the past.

(Effects of the Invention) According to the present invention, the control device of a key telephone system is distributed into a plurality of control units having substantially the same functions, and a common control bus, a common office line trunk, and a common By connecting the extension lines with mutual trunks, it is easy to install telephones or add office lines and extension lines.

In the above embodiment, a space-division type key telephone system was used, but the present invention can also be applied to a time-division type key telephone system. It is also possible to implement a telephone system.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing a small-scale embodiment of the present invention, Fig. 2 is an explanatory diagram for explaining the functions of an extension telephone used in the embodiment of the present invention, and Fig. 3 is an embodiment of the present invention. FIG. 4 is an explanatory diagram for explaining the configuration of the control unit used in the embodiment of the present invention. FIG. 4 is an explanatory diagram for explaining the signals exchanged between the control units used in the embodiment of the present invention. 1a, 1b, IC...office line, 2...office line common trunk, 3...extension mutual trunk, 4...control bus,
5a, 5b, 5Q...control unit, 6...extension line,
7,... extension telephone, 20... switching circuit, 21...
Office line incoming circuit, 22... call dialing conversion circuit,
and signal sending circuit at the time of incoming office line, 23... office line trunk incoming signal detection circuit, 24... extension mutual trunk monitoring circuit, 25... extension control circuit, 26... central control unit,
27...Serial conversion transmitting/receiving circuit, 28...Transistor for communication path intersection. Patent Applicant Oki Electric Industry Co., Ltd. Figure 1 Figure 2 Procedural Amendment (Mutsu) 1. Indication of the case 1982 Patent Application No. 025970 2 Name of the invention Distributed key telephone control device 3 Person making the amendment Relationship to the case Patent applicant's office (105) 1-7-12 Toranomon, Minato-ku, Tokyo
No. 4 agent

Claims (1)

[Claims] In the key telephone system, it consists of a plurality of control units having substantially the same functions, and each control unit is connected by a common control bus, a common central office line trunk, and a common mutual extension trunk. A distributed key telephone control device characterized by: