KR920009335B1 - Caller display system - Google Patents

Abstract

The device for displaying the call originating place comprises a means installed at the call originating telephone for displaying the receiving telephone number; a hookdetecting unit (10) detecting the hook state of receiving telephone by recognizing the dialing signal inputted from the call originating telephone; a dial pulse counter (16) counting the dialing signal outputted from the hook detecting unit (10); a circuit for recognizing the dial number by inputting the counted dial pulse signal; a tone encoder for converting the digital data signal of the recognized dial number into the analog signal; a means for displaying the telephone number of call originating place at the LCD (5) of receiving telephone.

Description

Caller ID display for phones

1 is a circuit diagram of a caller display device for a telephone according to the present invention.

2 is a block diagram of a receiver hook detection unit shown in FIG.

3 is a detail of the ring detector and the remote on-hook detector shown in FIG.

4 is a detailed view of a dial pulse counter.

5 is a detailed view of an acoustic signal generator.

6 is a schematic of a local off-hook detector.

* Explanation of symbols for the main parts of the drawings

3: transmission signal start detection circuit 4: liquid crystal display driver circuit

5 liquid crystal display 7, 11, 15 analog switch

8: tone decoder 9: transmission signal end detection circuit

10: Hook side detection unit 16: Dial pulse counter

17: Dial number recognition circuit 18: Tone encoder

The present invention relates to a source display apparatus for a telephone, which can be applied to an electronic or mechanical telephone to display a source, thereby enabling the recipient to make a call in a state in which the recipient is recognized.

Conventionally, it has been practical to install a liquid crystal display (LCD display unit) on one side of the telephone so that the telephone number of the destination can be displayed, so that the user can check the operation of the keypad by himself. Although it is possible to improve the convenience of using the phone because it can be sent out correctly, when receiving a call still can not know the calling party's phone number, like a normal phone, so the recipient selects the desired call Not only, but also the call proceeds in a state that can not know the origin at all, the situation is that the phone is being used for crime.

The present invention, in order to correct the closed end common to all conventional telephones as described above, by additionally installed in the foot and the receiving telephone, the destination telephone number is displayed when making a call, in particular, the telephone The purpose of the present invention is to provide a caller display device for a telephone so that the caller's phone number is displayed so that the desired call can be selected and the call can be comfortably received. .

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a circuit configuration diagram of a caller display device for a telephone according to the present invention. The present invention is provided in both the caller's telephone and the caller's telephone, whereby the caller and receiver telephone number display function is exhibited. That is, when the calling party picks up the handset 2 of the telephone 1 and dials the telephone number of the other party, the dual tone multi frequency signal (DTMF) is transmitted to the telephone lines RING and TIP. At this time, the transmission signal start detection circuit 3 applies a high state signal to the clear terminal CLR of the liquid crystal display driver circuit 4 so as to erase all numerals on the liquid crystal display 5 so as not to display any number. A high state signal is also applied to the set terminal S of the flop 6 so that a high state signal is output from the output terminal Q thereof.

Therefore, the analog switch 7 is turned on because the control terminal CTL ₁ is high. In this case, the DTMF signal transmitted to the ring line is input to the tone decoder 8 to be decoded, and this is a decoded digital signal. The same number as the DTMF signal applied to the liquid crystal display driver circuit 4 and eventually sent out can be displayed on the liquid crystal display 5.

Therefore, the caller can press the keypad continuously to confirm that the same number as the number pressed by his keypad is displayed on the liquid crystal display 5, and complete the transmission of the destination telephone number (for example, 547-7379).

In this way, after the telephone number transmission is completed, a ring tone signal or a busy signal is generated on the telephone lines RING and TIP. At this time, the transmission signal end detection circuit 9 generates a high state signal and the transmission signal is a start detection circuit. (3) is a low state after generating a high state signal during the initial operation of the keypad, the flip-flop (6) outputs a low state signal to its output terminal to disable the liquid crystal display driver circuit (4) In this state, the current state remains unchanged, and a low signal is also applied to the control terminal CTL ₁ of the analog switch 7 to turn off the switch 7 to turn off the telephone line RING and TIP. (8) is kept in isolation. Therefore, the caller checks if he / she has dialed the number correctly because the number corresponding to the number he / she has pressed is displayed on the liquid crystal display (5). Put it on top or press the hook switch (not shown) to resume the same operation as described above, and if you hear a ringing tone, wait for the handset to be picked up by the receiver.

In this way, the DTMF signal transmitted from the calling telephone is transmitted to the receiving hook detection unit 10 through the telephone office switchboard. In this case, the receiving hook detection unit 10 has a receiving difference between the handset 2 of the telephone 1. If you do not listen to each time the ringtone will output a high signal.

The generated high state signal turns on the analog switch 11 by turning the control signal CLT ₂ high so that the output of the transistor 12 is connected to the telephone lines RING and TIP.

On the other hand, since the low signal is applied to the control terminal CTL ₃ of the analog switch 15 via the oA gate 13 and the inverter 14, the telephone 1 is still blocked from the telephone lines RING and TIP. Will be.

Then, the dial pulse counted by the dial pulse counter 16 is applied to the tone encoder 18 via the dial number recognition circuit 17, and the encoded telephone number is amplified by the transistors 19 and 12. do. The amplified diode signal is carried on the telephone lines RING and TIP via the analog switch 11, in which case (CLT ₁ ) is high when the receiver does not lift the handset 2 of the telephone as described above. When the analog switch 7 is turned on, the telephone number of the call destination can be displayed on the liquid crystal display 5.

FIG. 2 is a detailed block diagram of the receiver hook detection unit 10 shown in FIG. 1. The relay 101 rings the subscriber telephone line in an inactive state in which ring signals RING and TIP are not input from the caller. To the detector 102. When excited by the output of the ring detector 102, subscriber telephone lines RING and TIP switch to the relay 103.

The ring signal is rectified by the capacitor C ₁ and the diode D ₁ shown in FIG. 3 and applied to the light emitting diode constituting the photocoupler PC ₁ through the resistor R ₁ . As the diode operates to generate light, the phototransistor inside it is activated. Therefore, since the power supply (+ Vcc) is grounded through the resistor R ₂ and the phototransistor, a low signal is applied to one terminal of the AND gate AND ₁ .

On the other hand, since the relay 103 shown in FIG. ₂ does not operate, the photocoupler PC ₂ constituting a part of the remote on-hook detector 104 shown in FIG. 3 does not operate and thus the power supply (+ Vcc). Is applied to the other input terminal of the AND gate AND ₁ through the resistor R ₃ . At this time, the AND gate (AND ₁₎ is to combine the logic of the input two signals to generate a signal of a low level counter (IC ₁₎ bar to be applied to the clock terminal (CLK) of the counter (IC ₁₎ is a ring pulse Increases the counter by 1 each time. After enough rings are pressed, the signal RE generated at the output terminal Q ₁₀ of the counter IC ₁ goes high. At this time, the output of the counter IC ₁ is applied to the base of the transistor Q ₁ via the resistor R ₄ to turn on the transistor Q ₁ . When the transistor Q ₁ is turned on, a current flows in the relay coil REL ₁ to operate the relay 101. Then, the relay 101 switches the subscriber telephone line to the relay 103. The output signal RE of the counter IC ₁ which turns on the relay 101 also resets the dial pulse counter 104 shown in FIG. 2 to prepare for counting the dialed pulses.

In the dial pulse counter 16 shown in FIG. 4, if the caller dials a predetermined number of telephone numbers, the received pulse is rectified by the diode D ₂ via the matching transformer TRNS. After low pass filtering by resistors R ₅ , R ₆ and condenser C ₂ , it is amplified in amplifier OP ₁ . The amplified signal is maintained at a predetermined level by the electrolytic capacitor C ₃ and the resistor R ₇ , and is sequentially inverted by the inverters I ₁ and I ₂ and counted by being input to the counter IC ₂ . The binary signal counted by the counter IC ₂ is used to drive the multiplexer IC ₃ , which switches one of the outputs C ₁ to C ₁₀ to a high state, and the output of the multiplexer IC ₃ is It is input to the dial number recognition circuit 17 shown in FIG.

5 is an internal circuit configuration diagram of the dial number recognition circuit 17, and generates a pulse train of 10 KHZ input to the NE555 counter IC ₄ and the SMS counter IC ₅ . The output of the counter IC ₅ outputs a signal for the corresponding telephone number, respectively. One of these signals is logically combined by the AND gates AND ₂ to AND ₆ when the output of the multiplexer IC ₃ is high and then applied to the tone encoder 18. Therefore, the tone encoder 18 generates a signal for a received telephone number. Whenever the outputs of the AND gates AND ₂ to AND ₆ are high, the OR gates OR ₁ to OR ₅ logic these signals. In combination, it is applied to transistor Q ₂ through resistor R ₈ to turn transistor Q ₂ on. When the transistor Q ₂ is turned on, a current flows in the relay coil REL ₂ to excite the relay 103 shown in FIG. 2.

When the relay 103 is excited, the photocoupler PC ₂ shown in FIG. 3 is connected to a telephone line.

Since the receiver did not lift the handset 2 of the telephone 1, the telephone line is connected with a resistor R ₉ connected in series with the photodiode. The DC voltage supplied from the telephone exchange switch turns on the photo transistor of the photo coupler PC ₂ to apply a low signal to the input terminal CLK of the counter IC ₁ .

If the caller stops the call operation for dialing the telephone, the port transistor in the photocoupler PC ₂ is not operated, and the output of the AND gate AND ₁ becomes high, so the counter IC ₁ is inputted. Goes low.

Accordingly, the output Q ₁₀ of the counter IC ₁ goes low so that the relay 101 of FIG. 1 does not operate, and the telephone line is connected to the ring detector 102 to maintain a standby state for subsequent calls. At this time, the pulse counter 16 shown in FIG. 4 receives the output signal RE of the inverter I ₃ and is reset to prohibit the generation of the signals C ₁ to C ₁₀ necessary for the generation of the dial pulse. .

If the handset 2 is received from the telephone 1 on the receiver side shown in FIG. 6, a low impedance path exists in the circuit via the photocoupler PC ₃ . In other words, when the handset 2 of the telephone 1 is lifted up, it is turned on by the power supply (+ Vcc) via the light emitting diode resistor R _{9 in the} photocoupler PC ₃ to generate a light beam, and thus the port transistor Since it is turned on, a low state signal is applied to the input terminal of the inverter I ₄ . At this time, the inverter I ₄ inverts the signal in the low state to the high state and turns on the transistor Q ₃ via the resistor R ₁₃ . When the transistor Q ₃ is turned on, the relay coil REL ₃ is activated to turn on the relay 105 shown in FIG. 1 and connect it to the handset telephone line so that a call with the caller can be made. In this case, the high state signal generated by the inverter I ₄ is inverted low through the inverter I ₅ to provide the dial detection switching signal DS-OFF to the dial number recognition circuit 17 so as to provide a liquid crystal display 5. Delete the phone number displayed in). In other words, when the receiver picks up the handset 2 of the telephone 1, the numeric display displayed on the liquid crystal display 5 by the dial detection switching signal DS-OFF disappears. You can do it.

When the receiver puts the handset 2 on the telephone 1, the relay 105 will return to its initial state as it is opened by the local off-hook detector 106 of the telephone line from the telephone exchange. As described above, the relay 105 serves to connect the handset 2 to the telephone line after passing through.

Therefore, if the handset is put down after the call is completed, the power supply from the telephone line L ₁ (L ₂ ) supplied to the entire circuit is cut off, and the calling party number and the destination telephone number displayed on the liquid crystal display are discarded. And since the transmission of the calling party number in the present invention is made in a very short time, it is received and displayed quickly, it can be used without any disruption to the call like a normal telephone, the overall configuration in the present invention The connection to the existing telephone is easier to use, and the manufacturing cost can be greatly reduced.

As described above, the present invention enables the user to receive a call while accurately knowing the originator, and the recipient can select and call the desired phone, thereby further enhancing the convenience of using the phone. It can be prevented from being misused in crime, and by installing the present invention 112 or 119 in a government office where the source needs to be identified quickly, the accident report can be made quickly and accurately. It is a new useful thing that has a great effect such as being able to prevent.

Claims (1)

A transmission signal start detection circuit 3 for detecting a tone transmission start signal when making a call, a transmission signal end detection circuit P for detecting a tone transmission end signal, and a liquid crystal display at the time of detecting the tone transmission start signal. The flip-flop 6 and the flip-flop 6 are operated to enable the driving circuit 4 and to keep the liquid crystal display driving circuit 4 in a current state when the tone transmission end signal is detected. Caller telephone to display the telephone number of the destination at the time of dialing on the liquid crystal display 5 including an analog switch 7 which is turned on and a tone decoder 8 which decodes the tone transmission signal during dialing and generates a digital data signal. Destination telephone number display means installed in the receiver; A dialing signal input from the caller's telephone is applied to count the dialing signal output from the receiving hook detection unit 10 for detecting the hook state of the receiver's telephone and the receiving hook detecting unit 10. A dial pulse counter 16, a dial number recognition circuit 17 for receiving the counted dial pulse signal to recognize a dial number, and a digital data signal for the recognized dial number converted into an analog signal; Under the control of the tone encoder 18 and the reception hook detection unit 10, the receiver includes an analog switch 11 for displaying the converted signal on the liquid crystal display 5. If not, the telephone number of the calling party is displayed on the liquid crystal display (5), and the calling party number is configured to display the telephone number so as to selectively receive the call. The source telephone display apparatus characterized by.

Images