KR920006207Y1 - Telephone automatic stand-by switching circuit - Google Patents

Abstract

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Description

Automatic reception state switching circuit of telephone

1 is a schematic diagram of a telephone according to the prior art.

2 is an automatic receiving state switching circuit diagram of a telephone according to the present invention.

* Explanation of symbols for main parts of the drawings

1: Bell signal circuit HS1, HS2: Hook switch

3: handset 4: handset

12 amplifier 15 comparator

19: timer 21-23: silicon controlled rectifier

23, 30: inverter

The present invention relates to an automatic reception state switching circuit of a telephone for easily receiving a telephone ringing even when the telephone receiver and the receiver of the telephone are not mounted on the main body.

When a telephone handset (handset) of a conventional telephone is incorrectly placed on the main body of a telephone after a child's mischief or a late-night call, it cannot receive an external call. Referring to FIG. Explain.

1 is a schematic diagram of a conventional general telephone, in which the hook switches HS1 and HS2 remain off when the handset (not shown) is in the correct position (when it is placed on the telephone body). Therefore, when telephone signals (TIP, RING) are input from the outside, the bell signal circuit 1 operates to generate a predetermined bell signal. When the user picks up the handset, the hook switches HS1 and SH2 are both turned on. do. When the hook switches HS1 and HS2 are turned on, the ring tone is stopped, the telephone signal is transmitted to the user's handset 4 through the resistor 2, and the voice signal spoken by the user is hooked to the hook switch HS2 at the talker 3. Is sent to the other party via).

If the user completes a call with the other party and then puts the handset on the main body of the telephone, the hook switch (HS1, HS2) is off again to wait in the state that can receive the incoming call.

However, in the telephone circuit shown in FIG. 1, the hook switch is not placed on the telephone main body after talking with the other party, or when the handset is not correctly positioned on the telephone main body because a child touches the telephone and the receiver. (HS1, HS2) remained on, so they could not receive incoming calls.

Therefore, the present invention has been devised in view of the above circumstances, and automatically checks the state of the phone to allow all-weather reception regardless of the position of the handset, thereby providing an automatic reception state switching circuit of the phone to provide the user's convenience. The purpose is to.

The present invention for achieving this purpose is to detect the amplified voltage signal applied to the receiver in the telephone to selectively supply the telephone signal input through the telephone line to the transmission, receiver and ring signal circuit by the hook switch And the amplified signal is compared with the reference voltage signal, and the first signal is output when the amplified signal from the amplifier is lower than the reference voltage signal, and the second signal is output when the amplified signal is higher than the reference voltage signal. A comparator for input, a timer for generating a predetermined control signal by the first and second signals described above, and a handset when the handset is turned off (when the hook switch is in the on state). In order to generate a signal in the standby state, the electronic switch of the silicon controlled rectifier and inverter, It is composed of another silicon controlled rectifier for driving the signal circuit.

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

2 is an automatic receiving state switching circuit diagram of a telephone according to the present invention, in which the same reference numerals as those in FIG. 1 denote the same parts.

First, when the user picks up the handsets 3 and 4 and talks with the other party, the hook switch HS1 is maintained in an ON state.

In this state, after the user completes a call with the other party, the user does not place the call or sign language (3, 4) on the phone main body (not shown), or the child or the handset (3, 4) is turned off by the child's prank. When put down, there is no signal applied to the receiver 4, so that no signal is applied to the heavy amplifier 12 through the rectifying diode 10 and the resistor 11, so that the resistors 11, 13, 14 are not. And no signal is amplified by the amplifier 12. At this time, the comparator 15 compares the reference voltage of the zener diode 16 connected to the non-inverting input terminal with the output signal of the amplifier 12 input to the inverting input terminal thereof, and thus the signal output from the amplifier 12. Since the output of the comparator 15 is high.

The output of the comparator 15 generated in this way is applied to the input terminal IN of the timer 19 via the switch 18 which is rectified by the diode 17 and pulled by the hook switch HS1. At this time, since the voltage applied to the input terminal IN of the high state is high, the timer 19 outputs a high state control signal through the output terminal OUT for a predetermined period of time through the diode 20 through the electronic switch ( In addition to the gate terminal of the silicon control rectifier (21, 22) constituting the 200, it is applied to the gate terminal of another silicon control rectifier (23). Here, a signal via the inverter 30 is applied to the gate of the silicon controlled rectifier 22.

When the high state signal from the timer 19 is generated for a predetermined time (this time can be arbitrarily adjusted by the user), the silicon controlled rectifier 21 is turned on because the high signal is applied to its gate, while the silicon is turned on. Since the low-state signal passing through the inverter 30 is applied to the gate of the control rectifier 22, the silicon control rectifier 22 is turned off. Thus, as the silicon controlled rectifier 21 is turned on, the handset 4 is placed in the external telephone reception standby state.

In addition, the high state signal generated by the timer 19 is applied to the gate terminal of the silicon controlled rectifier 23 to turn on the silicon controlled rectifier 23. If the telephone signal is input from the other party through the telephone line while the transmitter / receiver is turned down from the main body for a long time (ie, while the output of the timer 19 remains high), the silicon controlled rectifier 23 Since is turned on, a signal is applied to the bell signal circuit 1 to generate a bell signal. At this time, since the hook switch HS1 remains on, the telephone signal is applied to the silicon controlled rectifier 21 through the hookwatch HS1, and the silicon controlled rectifier 21 is connected to the gate terminal of the timer 19 at the timer 19. The generated high state signal is turned on because it is applied. Therefore, the other party's voice can be heard through the handset 3 even if the handset is not picked up from the main body.

When the voice from the other party is transmitted to the outside through the receiver 3, an analog signal is detected at the point A, and the signal is applied to the amplifier 12 through the diode 10.

In this case, the amplifier 12 amplifies the input signal and applies it to the comparator 15. The comparator 15 then generates a low state signal because the signal applied to its inverting input terminal is greater than the reference voltage signal by the non-inverting input terminal. At this time, since the diode 17 is not operated, a low state signal is applied to the input terminal IN of the timer 19, and the inverter 24 inverts the low state signal to a high state to turn on the timer 19. The reset signal RESET for resetting is applied to its reset terminal RST to reset the timer 19 to an initial state.

When the timer 19 is reset, a low state signal is generated at the output terminal OUT of the timer 19 so that a low state is applied to the gate terminal of the silicon control rectifier 23 so that the silicon control rectifier 23 is turned off. . As the silicon control rectifier 23 is turned off, the operation of the bell signal circuit 1 is stopped so that the bell signal does not ring.

In addition, since the low-state signal is applied to the gate terminal of the silicon controlled rectifier 21, the silicon controlled rectifier 21 is turned off, while the gate terminal of the silicon controlled rectifier 22 is connected to the gate terminal of the high state via the inverter 30. Since the signal is applied, the silicon controlled rectifier 22 is turned on. As the silicon controlled rectifier 22 is turned on, the call between the counterpart and the user is not interrupted.

On the other hand, if the user returns the handset to the telephone body before the output of the timer 19 is automatically turned off, the hook switch HS1 is positioned at the contact point OFF to receive a ringing tone from the other party. Will be.

Then, since the switch 18 which is pulled by the hook switch HS1 is turned off, no signal is applied to the input terminal of the timer 19, and the output of the timer 19 is opened. Therefore, since the silicon control rectifiers 21-23 do not operate in this case, the silicon controlled rectifiers 21-23 operate in the same reception mode as the reception standby state of the ordinary telephone.

As a result, when the user puts down the handset from the main body of the telephone (HS1 is turned on), the high state signal generated by the timer 19 is applied to the silicon controlled rectifier 21 and simultaneously to the silicon controlled rectifier 23. In this state, if the telephone signal is input from the outside in this state, the silicon control rectifier 23 is turned on and the bell signal circuit 1 operates, thus having the same effect as pressing the mechanical hook switch HS1. . In addition, since the silicon controlled rectifier 21 is operated, the voice of the other party is transmitted to the receiver 3. At this time, since the comparator 15 generates a low state signal to reset the timer 19, the output of the timer 19 becomes low so that the silicon controlled rectifier 23 is turned off so that the ring tone no longer sounds, but the silicon controlled rectifier (22) is activated so that the call in the room is not affected.

Importantly, it is preferable to appropriately set a time period when the output of the timer 19 becomes high when the handset is not mounted on the telephone main body. For example, it is preferable to set such a time so that the reception standby state can be automatically performed for a sufficient time when the transmitter and the receiver are turned down.

This design works like this, because it is possible to receive all weather regardless of the position of the handset. If necessary, the handset can be left at home afterwards. If you say one voice, the timer is reset, so you can keep talking.

Claims (1)

In the automatic reception state switching circuit of a telephone, the telephone signal inputted through a telephone line (TIP, RING) is selectively supplied to a transmission / reception and a ring signal circuit (1) by a hook switch (HS1, HS2). The amplifier 12 for detecting and amplifying the voltage signal applied to the receiver, and the amplified signal is compared with the reference voltage signal, the first signal when the signal amplified from the amplifier 12 is lower than the reference voltage signal. And a comparator 15 for outputting a second signal when the amplified signal is higher than the reference voltage signal, and a timer 19 for generating a predetermined control signal by the first and second signals. And the electronic switch 200 composed of the silicon control rectifiers 21 and 22 and the inverter 30 in order to generate a signal for putting the telephone to the reception standby state by inputting the control signal when the transmitter and the receiver are turned off. ), And And a silicon controlled rectifier (23) for driving the bell signal (1) circuit in a reception standby state.