JPH043146B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] Even if the handset is hung up while a hold request signal is being automatically sent from the telephone to the exchange, the line is prevented from being disconnected by preventing the telephone switch from outputting an off state. .

[Industrial application field]

The present invention relates to telephone systems, and more particularly to a line control system for preventing erroneous line disconnections that occur when the handset is hung up early when a hold request is made.

[Prior art and problems to be solved by the present invention]

In conventional telephones, the telephone line is disconnected when the handset is hung up (switch off) in any state during dialing.

By the way, in some PBX exchange systems, after a line is established, if it becomes necessary to transfer to another PBX phone, the line is temporarily disconnected for about 0.5 seconds to 1 second, as shown in Figure 3. Approximately 1 second after performing the operation, by sending a dial code pulse to "19" for approximately 1 second,
The transfer process is made possible by sending a hold request signal with a total length of approximately 3 seconds to the PBX exchange and causing the line control unit of the PBX exchange to hold the line.

However, at this time, if you transmit a hold request signal consisting of a hook and a dial code pulse of "19" with a single touch of the hold button, and then immediately hang up the handset after pressing the hold button, the hook switch will turn off. , there was a problem in which the above-mentioned ``chucking + 19 dial'' could not be correctly identified by the exchange, resulting in a failure in which the line was disconnected and transfer processing was impossible.

[Means for solving problems]

In order to solve the above-mentioned problems with the conventional system, the present invention prohibits the status output of the switch for a certain period of time when a hold request is made, so that the hold request signal is
It provides a means to ensure that it is identified by the PBX switch.

FIG. 1 shows the basic configuration of the present invention.

In FIG. 1, 10 is an electronic control circuit in the telephone, 11 is a switch, 12 is a pull-up resistor, 13 is an AND circuit, 14 is a hold button, and 15 is a pull-up resistor.
16 represents a pending request detection circuit, 16 a timer circuit, and 17 a pending request signal generation circuit.

The switch 11 is a handset (not shown)
is in the off state when it is placed, and a 1-level voltage is applied to one input of the AND circuit 13 via the pull-up resistor 12. When the handset is lifted up, the switch 11 is turned on.
A 0 level voltage is applied to the AND circuit 13.

The AND circuit 13 functions as a gate for inhibiting or permitting the status output of the switch 11.

The hold button 14 is pressed when a hold request is made.

The hold request detection circuit 15 detects that the hold button 14 has been pressed and starts the timer circuit 16.

The timer circuit 16 is set to operate with a timer time longer than the length of the pending request signal, and the output is a 1 level voltage when stopped, and becomes a 0 level voltage when activated by the pending request detection circuit 15. , when the timer time is reached, the 1-level voltage is output again. This output is applied to the other input of the AND circuit 13.

When the hold request detection circuit 15 detects that the hold button 14 is pressed, the hold request signal generation circuit 17
When activated, the hooking signal and dial code pulse as shown in FIG. 3 are automatically generated and output.

[Effect]

According to the configuration of the present invention shown in FIG.
After pressing the hold button 14, the control switch 11 is pressed until the sending of a series of hold request signals is completed.
Since output of the status is prohibited, even if you press the hold button and immediately hang up the handset, no effect such as disconnection of the line will occur.

Therefore, the PBX exchange will reliably execute the hold control.

〔Example〕

FIG. 2 shows the configuration of one embodiment of the present invention.

FIG. 2 specifically shows the details of the elements in the principle configuration of the present invention shown in FIG.
Reference numbers 10 to 17 are commonly used in FIGS. 1 and 2 to refer to the same elements, respectively.

The elements added in FIG. 2 are as follows.

21 is a key matrix for a plurality of button switches of the telephone; 22 is a key matrix 21
23 is a sense circuit that reads and scans the sense lines (vertical lines) of the key matrix 21; 24 is a sense circuit that drives and scans the drive lines (horizontal lines) of the key matrix 21; An AND circuit detects the simultaneous presence of pulses on a line, 25 is a flip-flop for timing correction, 26 is a counter that functions as a timer of approximately 3 seconds, and 27 is an AND circuit for timing control.

When the hold button 14 is pressed, key matrix 2
Multiple drive lines that make up 1 (horizontal lines in the diagram)
It is detected by scanning the sense line (vertical line in the figure).

When the AND circuit 24 detects that the hold button 14 is pressed, a count 26 is activated. counter 26
outputs level 1 when stopped, outputs level 0 while the timer is operating, performs a count-up (or count-down) of a clock (not shown), and returns the output to level 1 when a predetermined value is reached.

In the flip-flop 25, the sense circuit 23
It is turned on every time a pulse is detected on the sense line connected to the hold button 14, and remains on while the output of the AND circuit 27 is at 1 level (therefore, the output of the counter 26 is also at 1 level). However, when the counter 26 is activated and outputs 0 level, and the output of the AND circuit 27 becomes 0 level,
It is reset and maintains the off state (0 level output). At this time, the AND circuit 13 prohibits the status output of the switch 11.

Next, the counter 26 is activated for a predetermined timer period (approximately 3
When the count value corresponding to (seconds) is reached, a 1 level output is generated.If the flip-flop 25 is also turned on at this time, the AND circuit 27 outputs a 1 level, and the AND circuit 13 outputs the 1 level.
Allow status output of 1.

In the above embodiment, the hold request signal is automatically sent, but it is also possible to send it manually.

〔Effect of the invention〕

According to the present invention, even if the handset is put down early when a hold request is made, malfunctions such as disconnection of the line do not occur, and operability for the user is improved and efficiency can be improved.

[Brief explanation of drawings]

FIG. 1 is a basic configuration diagram of the present invention, FIG. 2 is a configuration diagram of an embodiment of the present invention, and FIG. 3 is a waveform diagram of an example of a hold request signal. In Figure 1, 11: Hook switch, 13:
AND circuit, 14: hold button, 15: hold request detection circuit, 16: timer circuit.

Claims (1)

[Claims] 1. An electronic control circuit is built-in, and line control is performed via this electronic control circuit. When a call is placed on hold, pressing a hold button causes a holding pulse and a predetermined dial code to be sent. In a telephone set that is required to transmit a hold request signal including a pulse, the electronic control circuit includes a timer circuit 16 having a predetermined timer time longer than the hold request signal;
Detecting the press of the hold button, the timer circuit 16
and a hold request detection circuit 15 for activating a hold request, and the line control method at the time of a hold request is characterized in that, after the timer circuit 16 is activated, the off-state output of the switch is prohibited until the predetermined timer time is reached. .