JPS6310630B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ringing signal control system for a time-division telephone exchange, particularly to a ringing signal control system suitable for a distributed control system having a main controller and a sub-controller. In order to operate the ringer relay that controls sending ringing signals to subscribers in the corresponding section during the dry period (window) of the ringing signal, a ringing signal interface is created in advance and the ringing signal with the interface is transmitted to each line. The present invention relates to a calling signal control method in a system having a ringing control device distributed to corresponding parts.

Conventional devices of this type employ a method in which a ringing control device directly controls interrelays, etc. to create a ringing window, so there is no guarantee that the interrelay will be turned off when the ringing voltage is low. However, when the ringing voltage is high, noise is generated when the relay is turned on and off, and this noise has the disadvantage that it can adversely affect the control and characteristics of the time-division telephone exchange.

The purpose of the present invention is to eliminate the drawbacks of the above-mentioned conventional method, and for this purpose, the zero crossing point of the ringing is monitored and the ringing waveform is set to the zero point according to the intertiming control signal from the main controller. The present invention provides a ringing signal control method that controls on/off of relays when crossing a ringing signal and creates a ringing signal window.

In order to achieve this objective, the present invention provides an interface for ringing signals that is notified to the sub-control device that controls the ringer relay of the line corresponding section.
timing (window dry period information),
The notification is made taking into account the inter time delay due to zero crossing in the ringing control device.

The ringing signal control method according to the present invention is a ringing signal control method for a distributed control time-division exchange having a main controller and a sub-controller, and detects a zero crossing point of ringing in a signal waveform from a ringing signal source. A ringing control device having a detection device is provided in common, and the device inter-controls the ringing signal at the zero crossing point of the ringing according to the intertiming control signal from the main control device and the signal from the zero crossing point detection device. and distributes the ringing with the inter to each line corresponding section, and notifies the sub-control device of the inter-timing that takes into account the inter-delay time of the ringing due to the zero crossing, and performs the sub-control based on the timing. The system is characterized in that under the control of the device, ringer relay control is performed on the line response section during the dry period of the ringing signal to send a calling signal to the subscriber.

Next, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 shows an embodiment of a system implementing the paging signal control method of the present invention, and FIG. 2 shows a timing diagram illustrating the operation of the system of FIG.

In FIG. 1, _1-1 is a switch module, which includes a ringer switch _S1 , a ring trip detector 2 for detecting on-hook and off-hook operations of _the handset, a relay drive device 3, and a maintenance unit. It is composed of a signal scanning device 4, a sub-control device 5, and the like. Here, the signal distribution device 6 is
The subscriber's status is sequentially scanned to monitor their on-hook and off-hook status. There are many other switches having the same structure as switch module _1-1 , and these are designated as switch module 1-k. 7 is a main control device, 14 is a control timing delay circuit, and 8 is a ringing control device, which includes a timing generation circuit 9, a zero crossing detection device 10, a flip-flop 11, a ringing interrelay drive device 12, and a ringing control device 8. Consists of Switch S ₂ . 13 indicates a ringing signal source. Although the line input to switch module _1-1 is not shown in Figure 1, it is 1200
As many subscribers as lines can be connected.

The operation of the calling signal control system according to the present invention configured as described above will be explained with reference to the timing shown in FIG.

First, the subscriber picks up the handset (off-hook).
When calling the other party, it is necessary to issue a ringing signal, which is done as follows. At first,
The main controller 7 generates a ringing intertiming signal and sends the signal to the ringing controller 8 (the signal is constantly being sent).
In this ringing control device 8, upon receiving the intertiming signal, a timing generation circuit 9 therein operates a flip-flop 11 which will be described later.
A control timing having a specific window period is generated by the operation of . That is, since the ringing signal source 13 generates, for example, a 20-cycle ringing signal as shown in FIG. 2a, the zero crossing detector 10 generates a waveform of the ringing signal as shown in FIG. The point where the zero point passes (intersects) is monitored, and a pulse as shown in c in the figure is generated each time the zero point occurs. At this time, according to the intertiming signal sent from the main controller 7, the timing generation circuit 9 generates a timing having a high level part (window) of, for example, 1.8 seconds and a low level part (window) of 0.2 seconds, as shown in FIG. 2b. A signal is generated and applied to the D input of flip-flop 11. As a result, when the pulse output c from the zero crossing detection device 10 is applied to the CP input of the flip-flop 11, a drive signal as shown at a low level in FIG. 4D is generated from the output side of the flip-flop 11. Since the drive signal is applied to the ringing interrelay drive device 12, the ringing switch _S2 is controlled based on the result. Therefore, the mutual timing of ringing in the ringing switch _S2 is determined by the output of the flip-flop 11 determined by the output of the timing generation circuit 9 and the output waveform c of the zero crossing detection device 10. Therefore, inter-ringing control is performed.

On the other hand, the control signal from the main controller 7 is processed by the control timing delay circuit 14 for the delay time necessary for generating the drive signal in the flip-flop 11.
The signal output delayed through the control timing _delay circuit 14 is outputted via the maintenance signal scanning device. Since the sub-control device 5 periodically scans the maintenance signal scanning device 4, the sub-control device 5 learns the window information of the ringing signal, that is, the dry period of the ringing signal, and identifies the ringing signal. During the dry period, that is, the period D in FIG. Period ringing can be performed.

In other words, as can be seen from the above, in the present invention, a delay equal to the predetermined maximum delay time of zero crossing is added to the timing at which the sub-control device 5 is notified.

Thereby, synchronization between the main control device and the sub-control device can be easily achieved in the distributed control system.
Moreover, since the ringing relay is turned on and off when the signal from the ringing signal source crosses zero, it is possible to reduce noise at the contact point and also send a ringing signal that is on for 1 second and off for 2 seconds to the subscriber. When supplied, three patterns (three phases) are possible in one cycle, and it is also effective in controlling multiphase ringing for these phases.

Furthermore, in a distributed control system using a main controller and a large number of sub-control devices, the cost of ringing trunks or subscriber circuits can be reduced by providing a common ringing control device in the sub-control devices and performing ringing window control in common. becomes possible.

In the above embodiment, a case is shown in which the control timing delay circuit 14 is provided, but the timing of the drive signal of the ringing interswitch _S2 is not delayed and is sent directly to the maintenance signal scanning device 4. Good too.

In addition, the ringing zero crossing detection and relay section is
A solid state relay with a zero crossing detection circuit or the like may also be used.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of a system implementing the paging signal control method of the present invention, and FIG. 2 is a timing diagram illustrating the operation of the system of FIG. 1. In the figure, _1-1 , 1-k are switch module, 2
is a ring trip detector, 3 is a relay drive device, 4 is a maintenance signal scanning device, 5 is a sub-control device,
6 is a signal distribution device, 7 is a main control device, 8 is a ringing control device, 9 is a timing generation circuit, 10 is a zero crossing detection device, 11 is a flip-flop, 12
13 shows a ringing interrelay drive device, 13 shows a ringing signal source, and 14 shows a control timing delay circuit, respectively.

Claims (1)

[Claims] 1. A ringing control device having a detection device for detecting a zero crossing point of ringing in a signal waveform from a ringing signal source in a call signal control system for a distributed control time-division exchange having a main control device and a sub-control device. is provided in common, and in accordance with the intertiming control signal from the main control device and the signal from the zero intersection detection device, inter control of the ringing signal is performed at the zero intersection of the ringing, and distributes the generated ringing to each line corresponding unit, and notifies the sub-control device of an inter-timing that takes into account the inter-delay time of the ringing due to the zero crossing, and based on the timing, under the control of the sub-control device, A ringing signal control method characterized by performing ringer relay control of a line corresponding part during a dry period of a ringing signal and sending a ringing signal to a subscriber.