JPS58168364A - Ringing system - Google Patents

Abstract

PURPOSE:To prevent an interruption time from being included in the transmission time of a call signal transmitted to a telephone set, by compounding respective signal transmission times of plural kinds of call signal to make intervals of the interruption time unequal. CONSTITUTION:In a timing signal tm' supplied to a central controller CC, two periods T1 and 4T1 are compounded. As the result, a call signal CR' supplied from a ringing device SIG to each subscriber's circuit LC by a relay R, which is driven at a time T2 by the signal tm', includes an interruption time T2 at intervals of the signal transmission time 4T1 synchronously with the timing signal tm' and includes three interruption times T2 at intervals of the signal transmission time T1 within every third signal transmission time 4T1. The device CC to which the signal tm' is supplied transmits a call signal IR or a call signal CR to select a point of time when a relay RG of the circuit LC should be driven.

Description

Detailed description of the invention: ta) Technical field of the invention The present invention relates to a ringing signal system, in particular a ringing signal device for supplying a ringing signal with short periods of interruption at predetermined time intervals, and a ringing signal transmission path during said interruption period. The present invention relates to a ringing signal system in an automatic switching system in which each subscriber circuit is equipped with a ringing signal sending circuit which opens and closes a ring and sends a plurality of types of intermittent ringing signals to telephones.

(bl Background of technology) In recent years, when automatic switching equipment sends a ringing signal f to a called telephone, it selects and sends a ringing signal with a different intermittent format depending on the type of incoming call. , the called telephone is able to identify the type of incoming call before answering. Figure 1 is a diagram showing an example of this type of ringing signal format. For example, in an automatic private branch exchange, when a telephone receives a call from a central office line, sends a ringing signal IR that repeats sending for 1 second and pausing for 2 seconds, and for the telephone receiving a call from the extension, the signal sending period (1 second) of the ringing signal IR is further intermittent by repeating sending for 0625 seconds and pausing for 0.25 seconds. By sending out the ringing signal SR, the called telephone can distinguish between a central office line call and an extension call before answering.

(C1 Prior Art and Problems FIG. 2 is a diagram showing an example of an automatic switching system to which the present invention is applied, and FIG. 3 is a diagram showing an example of the conventional calling signal system in FIG. 2. In the figure, n telephone stations housed in an automatic exchange are connected to a network NW via a subscriber circuit LC provided for each telephone.Each subscriber circuit LC has a relay RG
are respectively provided, and the calling signal CR supplied from the commonly provided calling signal device SIG is intermittent in a predetermined intermittent format based on the control signal from the central control device CC, and the corresponding telephone is called. A ringing signal IR or SR corresponding to the incoming call is sent to the station. Furthermore, the call signal device SIG
Since the calling signal continuously generated by the traffic signal OSC provided at the terminal is at a high voltage of, for example, 75 to 100 volts, if it is directly switched on and off by the relay RG, there is a risk of damaging the contact rg. In order to prevent damage to the contacts, the ringing signal control within the ringing signal device SIG is performed using a timing signal tm of a predetermined period TI (for example, 0.25 seconds) as shown in FIG. 3, which is supplied from the timing generation circuit TM. The relay R in the circuit RCTL is operated for a period T2 every period T1.
(for example, for 20 milliseconds) and contact r” of the relay R.
An intermittent calling signal CR is supplied from K to each subscriber circuit LC. The central control unit CC also generates a call signal C in synchronization with the timing signal tm supplied from the timing generation circuit TM.
By sending the control signal to the subscriber circuit LC during the interruption period T2 of R to drive the relay RG, the contact rg
is prevented from directly intermittent ringing signals. For example, in order to send a calling signal IR from the subscriber circuit LC, a calling signal IR' is sent to the corresponding telephone station by driving the relay RG as shown in FIG. In order to send signal SR, relay RG
As shown in FIG. 3, the calling signal SRj
is sent to the corresponding telephone station j.

As is clear from the above description, in a conventional paging signal system, the paging signal CR supplied from the paging signal device SIG to each subscriber circuit LC has an interruption period T2 for each period Tl. Therefore, the calling signal IR' actually sent out from the subscriber circuit LC which should send out the calling signal IR has a period T
This results in an interruption period 'r2 being included for each call, which results in the loss of the tone of the telephone bell.

(dl) Purpose of the Invention The purpose of the present invention is to eliminate the drawbacks of the conventional calling signal system as described above, and to realize a calling signal system that does not include an interruption period in the sending period of the calling signal sent to the telephone. exist.

te+ Structure of the Invention The object of the present invention is to provide a ringing signal device that supplies a ringing signal that is open for a short period of time at predetermined time intervals; In an automatic switching system in which each subscriber circuit is provided with a calling signal sending circuit that sends out different types of calling signals, the time intervals of the interruption period are set unequally by combining each signal sending period of the plurality of types of calling signals. This is achieved by

(fl　Embodiments of the invention An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a diagram showing a calling signal system according to an embodiment of the present invention in FIG. 2. It should be noted that throughout the plan, the same reference numerals indicate the same objects. In FIG.
As shown in FIG. 4, the timing signal t m ' supplied to
1 (according to the previous example, 1 second). As a result, the relay R driven for the period T2 by the timing signal t m ′ causes the call signal device SIG
However, the paging signal CR' supplied to each subscriber circuit LC is synchronized with the timing signal tm as shown in FIG. 4i transmission period T within signal transmission period ATl
1 includes three interruption periods T2.

Also, a timing signal Lm' is sent from the timing generation circuit TM.
The central control unit CC supplied with
Select the time point at which relay RG of C should be driven. For example, when sending out a paging signal IR from the subscriber circuit LC, the call signal IR in the subscriber circuit LC is
By operating relay RG during the signal interruption period T2 at the end of the signal sending period 4T1, the signal interruption period T2 is not included during the signal sending period 4Tl as shown in FIG. A calling signal IR can be sent. On the other hand, when sending out the paging signal SR from the subscriber circuit LC, the even numbered or odd numbered signal sending period T1 of the four signal sending periods TI divided by the three signal interruption periods T2. By operating the relay RG during the signal interruption period T2 at the start point and restoring the relay RG during the signal interruption period T2 at the end point of the signal transmission period TI, the call signal CR is directly interrupted by the contact rg. The calling signal SR as shown in FIG. 3 can be sent out without any trouble.

As is clear from the above description, according to this embodiment, the paging signal CR' supplied from the paging signal device SIG to each subscriber circuit LC has two signal transmission periods 4Tl and four signal transmission periods T1. The central control unit CC
When sending the calling signal IR to the subscriber circuit LC, a continuous signal sending period 4T1 is realized by using the signal sending period 4T1, and when sending the calling signal SR, the signal sending period TI is used. By using , the purpose of contact protection of relay RG is also achieved.

Note that FIGS. 2 and 4 are merely practical examples of the present invention, and, for example, the operating period of relay RG is not limited to that illustrated, and other signal sending periods 4T1 and TI may be used. Although it is also possible to use such a method, the effects of the present invention will not change in either case. Further, the intermittent format of the calling signal IR and the calling signal SR is not limited to that shown in the drawings, and many other modifications may be considered, but the effects of the present invention will not change in any case. Furthermore, it goes without saying that the automatic exchange to which the present invention is applied is not limited to that shown in the drawings.

fgl Effects of the Invention According to the present invention, in the automatic exchange, it is possible to prevent the interruption period from being included in the sending period of the ringing signal sent to the telephone, and to maintain the normal tone of the bell of the telephone. It becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a calling signal format, FIG. 2 is a diagram showing an example of an automatic switching system to which the present invention is applied, and FIG.
FIG. 4 shows an example of a conventional calling signal system in FIG.
The figure is a diagram showing a calling signal system according to an embodiment of the present invention. In the figure, LC is a telephone, LC is a subscriber circuit, NW is a network, CC is a central control unit, SIG is a call signal device, OSC is a traffic signal, RCTL is a call signal control circuit, and T
M is a timing generation circuit, RG and R are relays, rg
and r are contacts, IR, IR', SR, CR and CR
' indicates a calling signal, Lm and t m ' indicate timing signals, and T1 and T2 indicate periods. v, 1 Figure 3

Claims (1)

[Claims] A ring signal device that supplies a ring signal having a short interruption period at predetermined time intervals; and a ring signal device that opens and closes a ring signal transmission path during the interruption period to send a plurality of types of ring signals in different intermittent formats to a telephone set. In an automatic switching system having a sending circuit for each subscriber circuit, a calling signal system characterized in that the time intervals of the interruption period are provided unevenly by combining each signal sending period of the plurality of types of calling signals.