JPH0556163A - Re-dial system - Google Patents

Abstract

PURPOSE:To supply a re-dial system which can use a re-dial function even after a reset shift call concerning a busy line recall system (re-dial system) in an automatic private exchange. CONSTITUTION:A busy tone (BT tone) supervisory circuit SV is provided for the private line trunk TRK of the automatic private exchange PBX, and the called telephone set of an opposite station is busy-supervised. When the called telephone set which is called from a calling telephone set at first is busy, only a called party number before additionally dialled by the reset shift call is stored in the exchange or the calling telephone set. At the time of recall, the stored telephone number is dial-transmitted. Thus, re-dialling can be received without being denied by the restriction of the number of digits even after the multiple number of the digits is dialled with the reset shift call.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a busy line recalling system (redial system) in an automatic private branch exchange (hereinafter referred to as PBX), and more particularly to a system capable of realizing a redial function after making a reset shift call. Regarding

[0002]

2. Description of the Related Art Conventionally, in a PBX service, a telephone number of a called telephone is dialed to call the called telephone from a calling telephone, and when the called telephone is busy,
If you dial one digit after the called number you dialed,
The last digit of the called number is replaced by the number dialed in succession, and is called a reset shift call that can be called by a telephone within the called party's group (a group of telephones with the same high-order digit but differing only in the last digit) There is a service.
Even if this reset shift call is performed, if the called group is all busy, the PBX sends BT to the calling party.
Since the sound (busy tone) is returned, the caller gives up the call, goes on hook once, and after a while, dials the called number again to call.

In general, when the called party is busy, the calling party dials several times until the called party hangs up the busy call and is able to talk to himself. Is normal. On the other hand, recent telephone systems have a service function called redial. This is because the telephone or exchange stores the dialed number called to call a certain called party, and when calling the same called party again, by pressing a specific push button (redial button) or by pressing a specific number, This is a service in which the calling party does not have to dial the entire number of digits by automatically transmitting the stored dialed number of the called party.

[0004]

By the way, if the above-mentioned redial is subsequently performed after the reset shift call is made, the reset shift call will remember the number sent out after the called number. Sometimes when sending a lot of one-digit numbers, the dial number with an abnormal digit limit is stored in the telephone number, and all digits are sent at the time of redialing. The BT sound may be sent from the PBX and the connection may not be established. That is, there is a problem that the redial function cannot be used after the reset shift call.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a redial system in which the redial function can be used even after a reset shift call.

[0006]

In order to solve the above-mentioned problems, the redial system of the present invention, when all called telephones called by a reset shift call are busy,
In the method of calling the first called telephone again by redialing, a BT tone monitoring circuit is provided in the leased line trunk of the automatic private branch exchange to monitor the busy telephone of the called telephone of the other station, and to be called first from the calling telephone. When the called telephone is busy, only the called party number before the additional dialing by the reset shift call is stored in the exchange or the calling telephone, and the stored telephone number is dialed out when the call is recalled. It has the same structure as
In a system where multiple telephones in the own station are called by a reset shift call and the first called telephone is called again by redialing when all called telephones are busy, the called in-house called first by the automatic private branch exchange When the telephone is busy, only the called party number before the additional dialing by the reset shift call is stored in the automatic private branch exchange or the calling telephone set, and when the call is recalled, the stored first called telephone number is stored. The configuration is such that dial transmission is performed.

[0007]

[Effect] Even if a reset shift call is made, only the number of the called party who is first called is stored in the exchange or telephone, and when the call is reissued, only that number is dialed out, so that the number of digits is limited. Since the automatic private branch exchange normally accepts calls, it is possible to redial correctly.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram showing an embodiment of a redial system of the present invention (No. 1; when dial number is stored), FIG. 2 is a diagram showing an embodiment of the redial system of the present invention (No. 2; at redial), and FIG. FIG. 4 is a diagram showing a storage state of calling party information and a called number in a storage device, and FIG. 4 is a diagram showing an embodiment applied to a telephone of the present invention.

The same reference numerals denote the same objects throughout the drawings. In FIGS. 1 and 2, PBX is an automatic private branch exchange, CC is a central control unit, MM is a main storage unit, TRK is a dedicated line or an office line trunk, LPR and SV are local processors provided in the trunks, respectively. apparatus,
LC is an extension subscriber circuit, MDF is a main wiring board, and SUB is an extension subscriber.

First, the operation of storing the called party number during a reset shift call will be described with reference to FIG. Extension subscriber SUB
Dials the called party number to call the called party at the other station. The dialed number is notified to the central controller CC via. The central control device CC temporarily holds the received number, determines the trunk TRK to be connected based on this number, and notifies the trunk TRK of the dialed number via the route. In TRK, the received number is transmitted to the partner station as dial information. When the called party is busy when the dial information is sent, the other station sends back a busy tone (BT tone).
The BT sound returned is the BT sound monitoring device (S
V), the monitoring device SV notifies the local processor LPR via the detection of the BT sound. The local processor LPR notifies the central control device CC via this BT sound detection, and the central control device CC stores the dial number until the BT sound is held in the main storage device MM together with the caller information. Notify and the main memory MM stores them.

After that, the caller who hears the BT tone makes a reset shift call by continuously dialing the number of the telephone near the called party who called first. This dial number is also dialed to the partner station through the above-mentioned route.
When all the telephones called by the reset shift call are busy, the caller once lowers the handset to restore the line.

Next, the operation during redial will be described with reference to FIG. The calling party dials a special number for the redial service to call the called party again. This special number dialed number is notified to the central control device CC via the central control device CC so that the central storage device MM reads the numbers stored up to the BT tone detection corresponding to the caller. Notify via. The main memory MM reads the called number of the called party corresponding to the calling party information, and notifies it to the central processing unit CC via the same. The central processing unit CC notifies the notified number to the trunk TRK via the trunk TRK, and the trunk TRK sends the dialed number of the same called party as the previous call to the other station.

FIG. 3 shows the called party number stored in the main storage device in the PBX corresponding to the calling party information. The calling party information and the calling party number when the calling party makes a reset shift call. The dialed digits until the first BT sound is detected are stored.

In the above description, the case where the called party is accommodated in another station has been described as an example. However, when the called party is connected (extension call), the busy monitoring of the called party is not performed in the exchange. TRK for BT tone detection, which can be performed by loop monitoring of the calling subscriber line
The monitoring device SV provided inside becomes unnecessary. It is also possible to have the above functions in the telephone, not in the exchange, and in this case, the exchange does not need to add any functions,
As shown in FIG. 4, a monitor which is added to the control device CC and the main memory device MM that each telephone has in advance and detects the BT returned from the station side when the first called telephone is busy. The device SV may be provided in the telephone and the same operation as described above may be performed.

[0015]

As is apparent from the above description, according to the present invention, it becomes unnecessary to redial the called party number from the beginning when re-calling after the reset shift call.
In particular, when the number of the other party's number is large, the operability is greatly improved, and the connection time is shortened and erroneous dialing is prevented.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a redial system of the present invention (No. 1; when dial number is stored)

FIG. 2 is a diagram showing an embodiment of a redial system of the present invention (part 2; at the time of redial)

FIG. 3 is a diagram showing a storage state of calling party information and called number in a main storage device.

FIG. 4 is a diagram showing an embodiment in which the present invention is applied to a telephone.

[Explanation of symbols]

PBX ... Private branch exchange, CC ... Central control unit, MM ... Main memory unit, TRK ... Private line or office line trunk, LPR ...
Local processor, SV ... BT sound monitoring device, LC ... Extension subscriber circuit, MDF ... Main wiring board, SUB ... Extension subscriber

Claims (2)

[Claims] 1. A BT tone monitor circuit is provided in a private line trunk of an automatic private branch exchange in a method of redialing the first called telephone when all called telephones called by a reset shift call are busy. The called telephone of the other station, and if the called telephone first called from the calling telephone is busy, the called party before the additional dialing by the reset shift call is performed. A redial method characterized in that only the number is stored in the exchange or calling telephone, and the stored telephone number is dialed out when the call is recalled. 2. A method of calling a plurality of telephones in the own station by a reset shift call and calling the first called telephone again by redialing when all called telephones are busy, and is called first by an automatic private branch exchange. If the called telephone in the local station is busy, only the called party number before the additional dialing by the reset shift call is stored in the automatic private branch exchange or the calling telephone, and when the call is recalled, it is stored first. A redial method characterized by sending out the called telephone number of.