JPS61195058A - Telephone set - Google Patents

Abstract

PURPOSE:To listen easily with an appropriate tone volume of a receiving tone by increasing/decreasing the amplification factor of a cariable amplifier circuit between a telephone receiver and a receiving part according to the sizes of noise that is detected by a sound receiving element. CONSTITUTION:A noise detecting part 7 detects an electrical signal which a sound receiving element 8 generates due to peripheral noise and sets the amplification factor of a variable amplifier circuit 15 that is provided between a telephone receiver and a receiving part 4 to lower when the peripheral noise is less. On the other hand, when the peripheral noise is greater, the detecting part 7 raises the amplification factor of the circuit 15. Thus, it is made possible to listen easily the receiving tone by the generation of the appropriate receiving tone corresponding to the peripheral noise.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a telephone device having a function of receiving signals from a telephone line and driving a receiver.

(Prior Art) An example of a conventional receiving circuit for a telephone device is shown in FIG. In the figure, 1 and 2 are external terminals that are connected to the telephone line via an overvoltage protection circuit and a rectifier circuit, and 3 is a power supply unit that operates the internal circuit using a ringing signal from the telephone line or circuit current during a call. , 4 is a receiving section that receives the audio signal received by the terminal 1.2, and 5 is an amplifier circuit that drives the receiver 6.

! FIG. 4 is an operational waveform diagram of the telephone device of FIG. 3.

The operation of the telephone device shown in FIG. 3 will be explained using FIG. 4.

The calling signal from the telephone line is output at time tl by the power supply unit 3.
is detected, and the power supply section operates the internal circuit. t2 is the time when the receiver picks up the receiver, and the call starts from this time. In this example, the receiving amplification unit 5 receives a calling signal and
When the power is supplied from the line current during a call, the receiving signal is amplified during the call, and the handset 6t is driven. Conventionally, in such a telephone device, the amplification factor of the amplifying section is constant, or is simply companded depending on the line voltage, etc., or a part has a function of manually adjusting the amplification factor.

(Problems to be Solved by the Invention) A major disadvantage of such telephone devices is that, in general, the receiving sound is difficult to hear when the surrounding noise is large, and is too loud when the surrounding noise is small. Yes, there is. To solve this problem, in conventional telephone devices, the user covers the area around the transmitter or receiver with his or her hand depending on the ambient noise at the location where the telephone device is installed.

Alternatively, users had to perform operations such as removing the handset from their ears, resulting in the hassle of adjusting the receiving sound.

In order to eliminate the above-mentioned drawbacks, it is an object of the present invention to detect ambient noise with a separately provided sound receiving element, correct the received voice output using the electrical signal, and adjust the received voice to an appropriate level according to the magnitude of the ambient noise. The objective is to provide a telephone device that can transmit

(Tth Means for Solving the Problems) The telephone device of the present invention includes a receiving section that receives a signal from a telephone line and transmits the signal to a receiver, and inputs sounds surrounding the receiver and converts it into an electrical signal. a sound receiving element for detecting noise; a noise detection unit for detecting the level of noise by inputting the output of the sound receiving element;
The device includes a power supply unit connected between the receiver and the receiving unit, inputting the output signal of the noise detection unit, increasing the amplification factor when the noise becomes large, and supplying the noise.

(Example) Next, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a circuit diagram showing a main part of an embodiment of the present invention.

This embodiment includes a receiving section 4 that receives a signal from a telephone line and transmits the signal to a handset 6, a sound receiving element 8 that inputs sounds around the handset 6 and converts them into electrical signals, and this sound receiving element. 8
Noise detection unit 7 that detects the noise level by inputting the output of
and a variable amplification factor that is connected between the receiver 6 and the receiving section 4, inputs the output signal of the noise detection section 7, and increases the amplification factor when the noise is large and lowers the amplification factor when the noise is small. The power supply unit 3 is configured to include a power supply unit 3 that supplies power to the power supply unit.

The noise detection unit 7 is for the sound receiving element 8 to detect an electric signal generated by ambient noise and to set the amplification factor of the variable amplification circuit 15, and the circuit is a well-known amplification circuit or a variable gain circuit. Next, the operation of this embodiment will be explained using the fourth part (B).

Figure 2 is an operation waveform diagram of the embodiment shown in Figure 1.
Figure 4 shows the case when the ambient noise is small, and figure (B) shows the case when the ambient noise is large. The horizontal axis represents time t2I+-1, and the vertical axis represents compression imaging width V. In addition, a is connected to the power supply unit 3 for incoming call signals.
is detected and represents nine hours, from time t'1 to t2 and t3
The period from time t2 to t4 is the time when the calling signal is received.
t4 is the time when the receiver picks up the receiver and the conversation begins. b represents the electric signal t-i generated by the sound receiving element 80 which is input to the noise detection section 7. Output terminal 9 of channel receiving section 4
The output signal t-represents. d is an output signal of the output terminal IO of the variable amplification circuit 15, and the amplification factor is controlled by the noise detection section 7 via the signal path 11. In the fourth operation that simulates the case where the ambient noise is small, the noise detection unit 7 lowers the amplification factor of the variable amplification circuit 15, and the receiving signal supplied to the receiver 6 is as shown after t2 in d. , the amplitude becomes small. On the other hand, in the operation shown in Fig. β), which represents a case where the ambient noise is large, the noise detection section 7 is supplied to the telephone receiver 6 which increases the amplification factor of the variable amplification circuit 15. The amplitude of the reception signal remains large as shown at the time after t4 in d, and an appropriate reception sound can be generated according to the surrounding noise.

(Effects of the Invention) As described above in detail, the telephone device of the present invention lowers the volume of the receiver when the surrounding noise is large, making it easier to hear the receiver, and conversely, when the surrounding noise is low, It is possible to lower the receiving volume and generate a receiving sound at an appropriate volume according to the surrounding noise, and it has the effect that there is no need to operate the receiving sound that is difficult to hear or is too loud as in the past. ing.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an embodiment of the present invention, the second layout. (Bl is an operating waveform diagram of the embodiment shown in FIG. 1, FIG. 3 is a circuit diagram of the main part of an example of a conventional telephone device, and FIG. 4(a). It is an operation waveform diagram. 1. 2... terminal, 3... power supply section, 4...
...Receiving section, 5...Amplification circuit, 6...
...Telephone receiver, 7...Noise detection unit, 8...
... Sound receiving element, 9.10 ... Output terminal, 15.
...Variable amplification circuit. 5! , - Susumu Uchihara, Patent Attorney, Attorney 1. I'm... I Ni (1 9Fr lock (t) - War 41

Claims (1)

[Claims] a receiving section that receives signals from a telephone line and transmits the signals to the handset; a sound receiving element that inputs sounds around the handset and converts them into electrical signals; a noise detection unit that detects a noise level, and is connected between the receiver and the reception unit, and inputs an output signal of the noise detection unit;
A variable amplification circuit with a variable amplification factor that increases the amplification factor when the noise is large and decreases the amplification factor when the noise becomes small, and a power supply section that supplies power to the variable amplification circuit and the reception section. Telephone device featuring features.