JPH10224503A - Communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication equipment capable of promptly stopping the transmission of calling signals in the case that a telephone set is off-hooked while transmitting the calling signals. SOLUTION: The power supply part of this equipment is provided with a calling signal generation part 21 and an off-hook detection circuit 42 by overcurrent detection for detecting current change on the transmission line of pseudo calling signals generated by the calling signal generation part 21 and they are constituted so as to be operated when the telephone set is off- hooked and the line is terminated by DC resistance 50Ω-300Ω. The output of the pseudo calling signals is controlled by a CPU through a photocoupler 40 and off-hook detection signals are transmitted through the photocoupler 41 to the CPU. In the case that off-hook is detected, the CPU immediately stops the output of the pseudo calling signals through the photocoupler 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to off-hook detection during transmission of a call signal in a communication device such as a facsimile apparatus provided with a call signal generating means and an off-hook detecting means inside a DC power supply.

[0002]

2. Description of the Related Art Conventionally, there has been a facsimile apparatus which can activate an external (or built-in) answering machine mainly for recording a message or can sound a ringing tone of a telephone.

In such a facsimile machine,
There is a type in which a calling signal circuit is formed on a printed circuit board of an NCU or an independent printed circuit board, and a calling signal is transmitted from this circuit to activate an answering machine or ring a telephone.

Conventionally, in a call signal generation circuit,
In order to obtain a ringing signal of a high voltage (+24 V to -150 V), a DC-DC converter system is adopted, and a ringing signal (pseudo ringing signal) is output by intermittently stepping up a boosted voltage obtained on the secondary side. It has become.

On the other hand, it is necessary to guarantee the above-mentioned manual operation of the telephone. In order to detect the off-hook of the telephone, the line current detection means mounted on the NUC board detects the off-hook of the telephone.

[0006]

However, conventionally, in off-hook detection while a facsimile apparatus transmits a false call signal to ring a telephone,
A signal from the line current detecting means on the NCU is detected through a time constant circuit of C and R.

That is, from a timing point of view, off-hook detection during ringing of the telephone by the pseudo-call signal is activated when the pseudo-call signal is interrupted, so it takes time to detect the off-hook, and the off-hook of the actual telephone is off-hook. There was a problem that detection was delayed.

[0008] In addition, due to this delay, a pseudo ringing signal is input to the telephone from the time when the telephone goes off-hook until the transmission of the pseudo ringing signal is stopped. There was a problem giving.

FIG. 5 shows a conventional pseudo call (Ci) signal and the timing of its control signal. The control signal at the top of the figure shows the lower (-150 to + 24v) pseudo call (Ci).
i) A signal is generated. In this case, as shown in FIG.
Even if the telephone goes off-hook at the timing during the generation of the pseudo call (Ci) signal, the above problem occurs because the CPU can detect this off-hook only after the pseudo call (Ci) signal has been turned off.

[0010] This problem is not limited to the facsimile machine, but is common to communication devices connected to the line together with other terminals.

SUMMARY OF THE INVENTION An object of the present invention is to provide a configuration of a communication apparatus capable of promptly stopping transmission of a call signal when a telephone is off-hook during transmission of the call signal.

[0012]

According to the present invention, there is provided a communication apparatus for outputting a pseudo call signal to a connected communication terminal, wherein the pseudo call signal is output to the connected communication terminal. A pseudo-call signal generating means, an off-hook detecting means provided inside the pseudo-call signal generating means for detecting an off-hook of the communication terminal through a current change of the pseudo-call signal being output, and the off-hook detecting means. When the off-hook of the communication terminal is detected, a configuration having a control unit for stopping transmission of the pseudo call signal is adopted.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a facsimile apparatus employing the present invention.

The CPU 1 controls the entire facsimile apparatus according to a program stored in the ROM 2. The non-volatile memory 4 stores data to be stored even when the power supply 5 of the facsimile apparatus is cut off, for example, a registered telephone number.

The recording section 6 controls the RA under the control of the CPU 1.
The recording data stored in M3 is taken out and printed out as a hard copy, and is configured by a predetermined recording method, for example, a known recording method such as an electrophotographic method or a thermal method. The reading unit 7 binarizes data optically read using a CS (contact sensor) under the control of the CPU 1 and sequentially sends the binarized data to the RAM 3. The RAM 3 is used as an image memory or a work area for various processes described below.

The modem unit 8 comprises a G3 modem and a clock generation circuit connected to the modem.
Modulates the image data to be transmitted stored in the RAM 3 based on the control of the telephone line 1 via the NCU 9.
Output to 0. Further, the modem unit 8 is connected to the telephone line 1
0 is received and demodulated through the NCU unit 9,
The binarized data is stored in the RAM 3.

The NCU unit 9 controls the telephone line under the control of the CPU 1 to connect the modem unit 8 or the main telephone unit 11 and the answering machine 1
6 for connection. Regarding the main telephone unit 11 and the answering machine 16, either an external connection or a built-in connection can be considered.

In the present embodiment, it is assumed that the answering machine 16 is connected to the outside in an optional manner, is driven by the pseudo phone number generated by the calling signal generating section 21, and sounds a ringing tone.

The power supply section 5 generates a main power supply of the facsimile apparatus, and is configured to obtain a DC output from an AC input (primarily a commercial AC power supply on the primary side). In addition, a power source for a calling signal for activating the answering machine 16 and ringing the main telephone unit 11 is generated.

The call signal generating section 21 outputs a pseudo call signal (Ci signal) to the answering machine 16, and is built in the power supply section 5 as shown in this embodiment.
The Ci detector 22 detects a call signal from the line 10.

FIG. 2 is a block diagram showing the configuration of the NCU 9. The NCU unit 9 connects the line 10 to the telephones 11, 1
6, a CML relay 17 for selectively switching connection to the modem unit 8 for image communication, an off-hook detection circuit 18 for detecting a response from the main telephone unit 11, and an off-hook detection for detecting a response from the answering machine 16. Circuit 19 and answering machine 1
6 is provided with a K relay 20 for selectively switching connection between the line 10 side and the call signal generation section 21 side.

FIG. 3 is a flowchart showing the operation at the time of an incoming call in this embodiment. The fact that the answering machine 16 is connected is registered in the nonvolatile memory 4 in advance by a software switch or the like.

When there is an incoming call from the line 10 (step S1), the CPU 1 switches the K relay 20 to the A side (the side of the call signal generating section 21) before the answering machine 16 answers (step S2). , Ci detection is performed by the Ci detection unit 22 (step S3). Where Ci
If not (call signal), switch K relay 20 to B side (line 10 side) and return (step S).
13).

If the answer is Ci in step S3, the CML relay 17 is switched to the B side (modem 8 side) to capture the line 10 (step S4), and the call is received from a facsimile or received from a telephone. It is determined whether it is an incoming call (step S14).

On the other hand, when it is determined that an incoming call is received from the telephone, the software switch in the nonvolatile memory 4 is checked to determine whether or not the answering machine 16 is connected (or whether or not the answering machine is to ring when an incoming call is received). (Step S6). Here, if the answering machine 16 is set to be not connected, the operation shifts to a call operation by the actual telephone 11 (step S15). In this embodiment, the facsimile communication and the telephone call by the telephone unit 11 are omitted.
The activation operation of the answering machine 16 will be described.

That is, if it is determined in step S6 that the answering machine 16 is connected, the answering machine 1
6 is activated, pseudo call signal generating section 21 outputs a pseudo call signal of a frequency registered in advance in nonvolatile memory 4 a predetermined number of times or for a predetermined time (step S).
7).

Then, the response of the answering machine 16 is monitored by monitoring an off-hook response signal 41 from an off-hook detection circuit 42 (to be described in detail later) by detecting an overcurrent of the calling signal generation unit 21 in the DC power supply (step S8). If there is no time response, the process proceeds to the next processing (steps S9 and S10). If there is a response, the CML relay 17 is switched to the A side (the answering machine 16 side) (step S11), and a response process of the answering machine 16 is performed (step S12).

FIG. 4 is a circuit diagram showing a configuration of the power supply unit 5 having the calling signal generation unit 21 (including the off-hook detection circuit 42) which is a feature of the present embodiment.

As shown in FIG. 4, a power supply unit 5 includes an AC plug 30 for inputting an AC voltage to a primary side of a transformer 37 for transforming a commercial AC, a power switch 31, a fuse 3, and the like.
2, noise filter 33, rectifier circuit 34, smoothing circuit 3
5, and a power supply control unit 36 including overvoltage detection, overcurrent protection, PWM control of a switching power supply, and a shutdown circuit.

On the secondary side of the transformer 37, DC is connected to each circuit.
In addition to the regulator 38 that outputs voltage, the transformer 3
A paging signal generator 21 for switching the voltage obtained from 7 to generate the pseudo paging signal is provided.

An off-hook detection circuit 42 is inserted in the output circuit of the call signal generation section 21. The off-hook detection circuit 42 detects an off-hook of the answering machine 16 by detecting an increase in current of the line when the answering machine 16 is off-hook.

The detection signal, ie, the off-hook signal,
The signal is transmitted to the main circuit (CPU1) of the facsimile apparatus by the photocoupler 41. Further, a control signal for controlling the output of the pseudo call signal of the call signal generation unit 21 from the main body of the facsimile apparatus is also input via the photocoupler 40. That is, the main body circuit side and the call signal generation unit 21
It is electrically separated by a photocoupler 40.

FIG. 7 is a timing chart showing the timing of the pseudo call signal. This pseudo call signal is
It is a sine wave with an effective value of 75 VRMS, on which a DC voltage is superimposed. When the CPU 1 controls the output port of the control signal of the pseudo call signal in the parallel input unit (PIO) 12, the photocoupler 40 is on / off controlled,
When the photocoupler 40 is on, a sine wave of 75 VRMS is output to the output terminal of the calling signal generator 21, and when the photocoupler 40 is off, a DC voltage of +24 V is output. In this way, a pseudo call signal is generated.

Incidentally, the detection of a call signal of a normal answering machine is controlled so as to catch the line at a break of the call signal.

However, as described above, the conventional off-hook detection (FIGS. 5 and 6) during the transmission of the pseudo call signal is performed while the pseudo call signal is OFF (stopped). If the handset is picked up while the pseudo-call signal is off, the off-hook detection delay of several hundred ms causes the pseudo-call signal of the next cycle to be heard from the handset, which is unpleasant, and the response of the off-hook detection is accelerated. It is desirable to do.

In the present embodiment, in order to solve this problem, an off-hook detection circuit 42 for detecting an overcurrent of the call signal generation unit 21 is provided to speed up the response to the off-hook detection during the transmission of the pseudo call signal, By controlling the control signal of the call signal, the transmission of the pseudo call signal is immediately stopped.

The operation of this embodiment will be described in detail. FIG.
Indicates off-hook detection during pseudo call signal transmission.

If the answering machine of the answering machine 16 (FIG. 2) is picked up while the false answering signal is being transmitted, the false alerting signal generating circuit is terminated by the DC resistance of the answering machine 16 and a DC loop is formed. The DC resistance of the telephone set at this time is defined by technical standards, and is 50Ω to 300Ω.

That is, the off-hook detecting circuit 42 based on the overcurrent detection of the calling signal generating unit is capable of reducing the DC resistance from 50Ω to 3
It is configured to operate when terminated with 00Ω.
The overcurrent detection circuit 42 changes the DC resistance from 50Ω to 30Ω.
When terminated at 0Ω, the photocoupler 41 is turned on and an off-hook signal is output (second and fourth steps in FIG. 8).

When the CPU 1 detects this off-hook signal, it can immediately cut off the pseudo call control signal via the photocoupler 40 and stop outputting the pseudo call signal (third stage in FIG. 8). Here, of course, the hardware circuit is replaced with the photocouplers 41 to 40 without using the CPU 1.
Needless to say, the output of the pseudo-call signal may be stopped by providing the intermediary between them.

First, the overcurrent detection circuit 4
2, the off-hook can be detected immediately and the pseudo-call signal can be stopped, so that an unpleasant pseudo-call signal is not output from the handset regardless of the timing of lifting the handset.

On the other hand, a configuration for detecting off-hook of the answering machine 16 during facsimile (or data) communication in the above configuration will be described. Here, the configuration of each unit will be described in more detail.

Normally, when the pseudo call signal is not being transmitted, the pseudo call signal generation unit 21 outputs a predetermined DC voltage (+2
4V) (see FIG. 7), but during facsimile (or data) communication, the answering machine 16
Switch 0 to A side. In other words, the answering machine 16
A voltage of +24 V is applied.

Conventionally, when the answering machine is off-hook, +24 V used for a false call signal is applied to the line of the telephone, and the current flowing when off-hook is set to N.
The off-hook of the answering machine is detected by detecting with a current detection IC using a photocoupler on the CU, a current detection reed relay, and a Hall element.

For example, as shown in FIG. 11, a DC loop closure of a line is detected by a varistor VZ, light emitting diodes PC1 and PC2 of a photocoupler connected in parallel with a capacitor C, and a resistor R5. Get the signal. In this embodiment, this circuit is provided as an off-hook detection circuit 18 for detecting a response from the main telephone unit 11 and an off-hook detection circuit 19 for detecting a response from the answering machine 16.

Further, as described above, in this embodiment, the off-hook detection circuit 42 for detecting an overcurrent is provided, but this is configured as shown in FIG. In FIG. 9, the call signal generation unit 21 includes an ON / OFF unit 21a, a frequency variable unit 21b, and an output drive unit 21c. The overcurrent detection circuit 42 shown in FIG.
And an operational amplifier 42 a and a photocoupler 41.

In the conventional off-hook detection, all of the off-hooks during pseudo call transmission, communication, communication and standby are detected only by the off-hook detection circuit 19 shown in FIG. For this reason, in the off-hook detection during pseudo call transmission (while the telephone is ringing), a delay occurs due to the CR time constant circuit, and a pseudo CI tone leaks from the handset, which is uncomfortable.

Therefore, in this embodiment, as described above, the off-hook detection during pseudo call transmission is performed by the call signal generation circuit 2.
1 by the current detection circuit 42 (FIG. 10).

During communication, off-hook is detected by the off-hook detection circuit 18 or 19 (FIG. 11). That is, during communication, the answering machine 16 switches the K relay 20 to the A side, and when +24 V voltage is applied to the answering machine 16, when the phone is off-hook, the impedance (DC resistance) of the phone increases. 50-30
The current increases to 0Ω, and the current increases. This current is detected by the off-hook detection circuit 19 (FIG. 11), and an off-hook response signal is output.

This off-hook signal is monitored by the CPU 1,
When an off-hook is detected, the output of the pseudo-call control signal is prohibited for the off-hook response signal, thereby stopping the transmission of the pseudo-call.

As described above, the off-hook detection is performed by the overcurrent detection circuit 42 during the pseudo call and by the off-hook detection circuit 19 (18) similar to the conventional one during the communication, so that the off-hook during the pseudo call is immediately performed. In response, the false call is stopped, and an unpleasant false call signal is not output from the handset.

Also, off-hook detection during communication can be performed only by the overcurrent detection circuit 42 (FIG. 10) provided in the call signal generation circuit 21 without using the off-hook detection circuit 19 (18). In this case, +24 V is output to the line when no pseudo call signal is generated.
The off-hook of the communication terminal can be detected by detecting a change in current corresponding to the connection of the DC resistance to 50 to 300Ω due to the off-hook of the telephone.

FIG. 12 is a block diagram showing the configuration of a key telephone system in which an off-hook detection circuit is provided inside dedicated telephone 105.

In FIG. 12, a dedicated telephone 105 connects a main unit 101 with a telephone line 103 and a control line 104.
Is a four-wire button telephone connected via a telephone. Main device 101 has a function of exchanging a plurality of dedicated telephones. Also,
The main device interface 122 of the dedicated telephone 105 is
A control code such as a call code is received from the main device 101,
Further, a control code such as an off-hook code is transmitted to main device 101.

On the other hand, the dedicated telephone 105 is
6 is connected to a two-wire facsimile 107, and the dedicated telephone 105 is connected to the facsimile machine 107.
To the main device 101. The relays 117a and 117b connect the main device 101 and the facsimile device 107.

The DC voltage circuit 1 of the dedicated telephone 105
23 has a built-in pseudo call signal generation circuit 119 and an off-hook detection circuit 132 during pseudo call signal transmission. Furthermore, the dedicated telephone 105 has a control circuit 121, a nonvolatile memory 124, a hook switch 126, an amplifier 127,
A speaker 128, a communication circuit 129, a handset 130, a DC loop detection circuit 131, and the like are provided.

FIG. 13 shows the operation of the dedicated telephone 105. When the main unit interface 122 detects the calling code (step S61), the control circuit 121 uses the square wave of the frequency registered in advance in the nonvolatile memory 124 as a control signal as a pseudo calling signal generator 119 built in the DC power supply 123. To generate a calling signal and send it to the facsimile apparatus 107 via the communication line 106 (step S62).

The response of the facsimile apparatus 107 to the pseudo call, that is, whether or not the facsimile apparatus 107 has started up by the pseudo call is determined by the DC power supply 1.
The monitoring is performed by monitoring the off-hook response signal from the off-hook detecting means 132 using the overcurrent detection of the 23 pseudo call generating section.

If it is detected that the facsimile apparatus 107 has responded to the off-hook response signal within the predetermined time (steps S63 and S64), the transmission of the pseudo call signal is immediately stopped, and the relay 117 is switched. The communication line 103 is connected to the facsimile machine 107 (step S66), and the process proceeds to facsimile communication (step S67). If there is no response, the process moves to the next process.

In such a configuration using the dedicated telephone 105, an off-hook detection circuit is provided inside the dedicated telephone 105, so that not only the telephone but also the facsimile apparatus can detect the response.

Needless to say, the present invention can be applied to various data communication apparatuses other than the facsimile apparatus and the key telephone system, and other communication apparatuses.

[0063]

As is apparent from the above description, according to the present invention, the off-hook detecting means for detecting the off-hook of the communication terminal through the current change of the pseudo call signal being output is provided inside the pseudo call signal generating means. Since the configuration provided in (1) is adopted, the response time of the off-hook detection of the telephone can be shortened, and the transmission of the pseudo-call signal can be stopped immediately according to the off-hook even while the call signal is being transmitted.
An excellent effect is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a facsimile apparatus employing the present invention.

FIG. 2 is a block diagram showing a configuration of an NCU unit of the device shown in FIG.

FIG. 3 is a flowchart showing the operation of the device of FIG. 1 at the time of an incoming call;

FIG. 4 is a circuit diagram showing a configuration of a power supply unit of the device of FIG.

FIG. 5 is a timing chart showing the timing of a conventional pseudo call signal.

FIG. 6 is a timing chart showing off-hook detection during transmission of a conventional pseudo call signal.

FIG. 7 is a timing chart showing a timing of a pseudo call signal of the apparatus of FIG. 1;

FIG. 8 is a timing chart showing off-hook detection of a pseudo call signal of the apparatus of FIG. 1;

FIG. 9 is a block diagram showing a configuration of a peripheral portion of the off-hook detection circuit of FIG. 4;

FIG. 10 is a circuit diagram showing an internal configuration of the off-hook detection circuit of FIG.

FIG. 11 is a circuit diagram showing an example of an internal configuration of the off-hook detection circuit of FIG. 2;

FIG. 12 is a block diagram showing a configuration of a key telephone system employing the present invention.

FIG. 13 is a flowchart showing the operation of the dedicated telephone shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CPU 2 ROM 3 RAM 4 Non-volatile memory 5 Power supply part 6 Recording part 7 Reading part 8 Modem part 9 NCU part 10 Line 11 This telephone 12 PIO 16 Answering machine 21 Call signal generation part 42 Overcurrent detection circuit

Claims (2)

[Claims] 1. A communication device for outputting a pseudo call signal to a connected communication terminal, comprising: a pseudo call signal generating means for outputting a pseudo call signal to the connected communication terminal; and a pseudo call signal generating means provided inside the pseudo call signal generating means. An off-hook detecting means for detecting an off-hook of the communication terminal based on a current change of the pseudo-call signal being output, and stopping the transmission of the pseudo-call signal when the off-hook detection means detects the off-hook of the communication terminal. A communication device, comprising: a control unit that performs the control. 2. The signal level of the false call signal is configured to swing between a predetermined positive voltage value and a predetermined negative voltage value and to cross 0 volts. Pseudo call signal generating means is configured to output a signal, and in a state where the call signal is not generated, an off-hook of the communication terminal is detected by detecting a current change in a state where the predetermined DC voltage is applied. The communication device according to claim 1, wherein: