JPS6161746B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a central office line callback system that eliminates the troublesome redialing operation.

One of the services provided by PBX extensions is callback. This callback is sent when the caller dials the outgoing central office line access code.
If the PBX's central office line is busy, the PBX returns a busy tone to the caller. Upon detecting this, the caller stops dialing the central office line and instead operates an automatic callback key to make the central office line available. and PBX
As soon as the central office line becomes vacant, an automatic call-back signal is sent to the caller's telephone that has been registered as a call back, and when the calling party responds to this, the vacant central office line is seized. Therefore, the caller can check the dial tone from the PBX (office side) and dial as soon as the central office line becomes vacant.

Although this callback system has great effects, such as being able to reduce the waiting time on the caller side, it also has the following drawbacks. That is, when receiving an automatic call return, the caller must immediately dial the central office line in response. To do this, it is necessary to remember the dial number as soon as possible, or if you have forgotten it, it is necessary to check the dial number again by looking at the telephone directory or telephone memo. Moreover, in the worst case scenario, there is a risk that the user may forget where they dialed first. For this reason, it was often not possible to make full use of the callback function.

The present invention has been made in consideration of the above circumstances, and its purpose is to eliminate the troublesome operation of additional dialing when returning calls, and to provide a practical method for effectively utilizing the function. The purpose of the present invention is to provide a highly flexible central line callback system.

That is, the present invention memorizes all digits of the above-mentioned central office line dial when all central office lines are busy at the time of central office line dialing, and when an empty central office line occurs, calls back the calling party's telephone and By detecting a response and transmitting all the digits of the stored office line dial to the office line, the above object is effectively achieved.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 was constructed by applying the example method.
FIG. 2 is a schematic configuration diagram of EPABX.

Standard telephone (STT) 1 and electronic key telephone (EKT) 2 are connected to line circuits 3 and 4, respectively.
It is connected to the communication path network 5 via. Further, central office lines 7 ₁ -7n are connected to this communication path network 5 via central office line trunk circuits (COT) 6 ₁ -6n, respectively. The communication paths between these telephones 1 and 2 and between the telephones 1 and 2 and the office lines 7 ₁ to 7n are formed via the communication path network 5 under the control of a central processing unit (CC) 8. . Thus, the central processing unit CC8 transmits and receives control data to and from the storage device (MEM) 9, and also transmits and receives control data to and from the telephones 1 and 2 via the line circuits 3 and 4.
Also, control data is sent and received to and from the station via the trunk circuits 6 ₁ to 6n to control the communication path network 5 and control the operation of each line circuit 3, 4 and trunk circuits 6 ₁ to 6n. I do.

That is, basically, when the telephones 1 and 2 operate the hook-off or line selection key, the operation signal is detected by the central processing unit 8 via the line circuits 3 and 4. When the central processing unit 8 confirms this, it sends a dial tone to the telephones 1 and 2 that made the calling operation, and after the telephones 1 and 2 detect this dial tone, they perform the destination dial operation. . In this way, a series of dial signals given from the telephones 1 and 2 are input to the central processing unit 8. Then, if the dial signal indicates an extension, the central processing unit 8 checks the usage status of the extension destination from the registered contents of the storage device 9, and if the destination is vacant, sends a calling signal to the telephones 1 and 2. At the same time, a ring back tone is sent to the calling side telephones 1 and 2. Then, the response from the destination telephones 1 and 2 is detected, and the communication path network 5 is controlled to form a communication path between the extension lines.

Further, when the dial signal includes the access code of the office lines 7 ₁ to 7n, for example, when the "0" code is input first, such as when making a "0" call,
Empty trunk circuits 6 ₁ to 6 from the contents of the storage device 9
Find n. When an empty trunk circuit 6 ₁ to 6n is found, the trunk circuit is captured and a communication path is established between the calling side telephones 1 and 2 and the empty trunk circuits 6 ₁ to 6n via the communication path network 5.
A dial tone is then sent to the telephones 1 and 2. When you confirm this dial tone and dial from the above-mentioned telephones 1 and 2, the dial signal is transferred from the trunk circuits 6 ₁ to 6n to the central office line 7.
₁ to 7n, and the above-mentioned dial signal is sent to the station. As a result, a call between the above-mentioned extension telephones 1 and 2 and an outside line is established.

By the way, the EPABX according to this method has the following callback function. That is, when the central processing unit 8 detects the central office line access codes from the telephones 1 and 2 and searches for vacant trunk circuits 6 ₁ to 6n, if all central central processing units 7 ₁ to 7n are busy, the A busy tone is sent to the calling telephones 1 and 2. Even when the telephones 1 and 2 confirm this busy tone, they dial the central office line as if there was an empty trunk as usual, and then operate the callback command key. At this time, the central processing unit 8 stores all digits of the above-mentioned office line dial, and also stores the callback information together with the codes specifying the telephones 1 and 2. Incidentally, conventionally, after confirming the busy tone, the central office line dialing is stopped, a callback command is processed, the central processing unit 8 waits for the callback, and the central office line dialing is performed again. In this regard, in this system, as described above, the central office line dialing operation is performed at that point upon confirmation of the busy tone. When the vacant trunk circuits ₆₁ to 6n are detected, a callback signal is sent to the registered telephones 1 and 2, and upon receiving the response, the previously memorized office line dial is transferred to the vacant trunk circuit. 6 ₁ to 6n to central office lines 7 ₁ to 7n. Therefore, when making a callback, it is not necessary to perform dialing again.

FIG. 2 shows an example of the control flow of the central processing unit 8 equipped with such a callback function.

Therefore, when the trunk circuits ₆₁ to 6n are all busy, a busy tone is emitted to the telephones 1 and 2, and the busy tone is stopped when the first digit of the central office dial from the telephones 1 and 2 is detected. . Then, the first digit of the dial signal is stored in the storage device 9 along with the access code of the central office line, and the subsequent dial signal is received and all digits thereof are stored. Data storage in the storage device 9 involves, for example, registering a central office line access flag B, a central office line access code C, and a dial code D in the extension corresponding storage area A, as shown in FIGS. 3a and 3b. It is done by folding. The access flag B is also used as a flag for instructing automatic callback. Thereafter, the central processing unit 8 sequentially reads out the CO access code from the flag-set terminal memory to detect empty trunk circuits 6 ₁ to 6n, and if any trunk circuit 6 ₁ to 6n becomes empty, it Make a reservation. Then, it sends a callback signal to telephones 1 and 2 and waits for a response. If this response is not obtained after a predetermined period of time has elapsed, the callback is stopped, and the reservation of the vacant trunk circuits 6 ₁ to 6n is canceled;
It also resets the stored data in the extension correspondence storage area. On the other hand, if there is a response to the callback within the predetermined time, the reserved vacant trunk circuits 6 ₁ to 6n are connected to the terminal line circuits 3 and 4, and the stored dial signal is sent to the central office line. Send all digits of . Thus, the registered call back is completed and the central office line dial is automatically sent.

Note that when dialing a central office line using an automatic dial key, all digits of the dial number can be given to the central processing unit 8 by the first dial key operation, so when a busy tone is detected, the callback designation operation is simply performed. It is also possible to perform only the following. It is also possible, of course, to obtain a dial signal input while the busy tone is being sent and recognize this as a callback designation.

Thus, according to this system, by simply registering a callback in advance, when a free office line becomes available, the line can be quickly connected and the dial signal for that office line can be automatically sent. Therefore, there is no need for the trouble of dialing again in the conventional system, and there are no inconveniences such as forgetting the dial number. In addition, if you are called back and forget who the other party is, you can connect to the line and check who the other party is and remember the details, and if you are unsure, you can cancel the call. , and its effective use can be achieved. It also eliminates the need for redialing.
EPABX also has the advantage of smoother processing control.

Note that the present invention is not limited to the above embodiments. For example, the setting of the callback response waiting time, the callback format, the response format, etc. may be determined according to the specifications. Further, the control flow can be modified as appropriate, and in short, the present invention can be implemented with various modifications without departing from the gist thereof.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an EPABX configured by applying an embodiment of the present invention, FIG. 2 is a diagram showing an example of its control flow, and FIGS. 3a and 3b are diagrams showing the memory configuration and its data format. It is a figure showing a mat. 1...Standard telephone, 2...Key telephone, 3,
4... line circuit, 5... call path network,
6 ₁ to 6n...Trunk circuit, ₇₁ to 7n...Station line, 8...Central processing unit, 9...Storage device.

Claims (1)

[Claims] 1. A means for storing all digits of the dial signal that is input when the outgoing station line in the PBX is busy, and a means for storing all digits of the dial signal that is input when the outgoing station line is busy, and when the above outgoing station line becomes vacant, the vacant station line is secured and the above dial signal is transmitted. means for transmitting a call back signal to the input calling telephone; means for detecting a response from the calling telephone to the call return signal and transmitting all digits of the stored dial signal to the secured office line; A central office line callback system characterized by the following: