JPS63237647A - Ringing tone sounding circuit for telephone set - Google Patents

Abstract

PURPOSE:To always automatically adjust the sound volume of a ringing tone to a proper level by changing the attenuation factor of an attenuating means in accordance with the level of an inputted noise signal. CONSTITUTION:A microphone 16 gathers ambient noises and a signal corresponding to the noise level is digitized by an A/D converting circuit 17 and is outputted to a control circuit 18. The control circuit 18 controls a resistance varying circuit 15 so that this circuit 15 has a resistance value corresponding to the inputted noise level. Since a ringing tone driving signal is attenuated by the resistance value of the resistance varying circuit 15 and is outputted to a speaker 14 in this case, the ringing tone whose level corresponds to the resistance value of the resistance varying circuit 15 is emitted from the speaker 14. Thus, the sounding level of the ringing tone corresponding to the ambient noise is automatically set by the control circuit 18 and the ringing tone which is always distinct and has a proper sound volume is emitted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to an incoming ringing circuit for a telephone that sounds a ringing tone when an incoming call is received.

(Prior Art) FIG. 4 is a block diagram showing an example of an incoming call ringing circuit of a conventional telephone. An incoming signal on the office line 10 is input to an incoming circuit 12 via a diode bridge 11. The incoming call circuit 12 generates an incoming driving signal in synchronization with (or based on) the incoming signal, and outputs this to the speaker 14 via the volume 13. Therefore, the level of the caller's ringing from the speaker 14 can be adjusted by manually operating the volume 13. Therefore, if the adjustment timing of the volume 13 is out of sync with the surrounding noise level,
There have been drawbacks such as the ringing tone being loud despite the low tone level and the ringing tone being too low to be heard even though the surrounding noise level is high.

(Problems to be Solved by the Invention) In conventional incoming call ringing circuits, the level of the incoming caller's ringing was adjusted by the user manually operating the volume, so the level of ambient noise and the level of the ringing tone were adjusted. The problem was that the ringtone was too loud or too soft. Also, adjusting the volume in such cases is troublesome and rare. SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks and provides a ringtone ringing circuit for a telephone that automatically adjusts the volume of the ringtone to an appropriate level depending on the level of ambient noise.

[Means for solving the problems of the invention] The present invention creates an incoming drive signal from an incoming signal input from a central office line, etc., and outputs it to a loudspeaker. The incoming call ringing circuit that makes the incoming call drive signal sound VJ includes attenuating means for attenuating the incoming call driving signal and outputting it to a loudspeaker, a sound collecting means for collecting ambient noise and inputting a noise blind signal, and a sound collecting means for collecting ambient noise and inputting a noise blind signal, and control means for changing the attenuation rate of the attenuation means according to the level.

(Function) In the incoming call ringing circuit for the telephone according to the present invention, the control means changes the attenuation rate of the attenuation means in accordance with the noise signal level input from the sound collection means. As a result, the level of the incoming call driving signal input to the loudspeaker is changed according to the ambient noise, and the level of the ringing tone sounded from the loudspeaker is controlled by the ambient noise.

(Example) An example of the present invention will be described below with reference to the drawings. 1st
FIG. 1 is a block diagram showing an embodiment of a ring tone ringing circuit for a telephone according to the present invention. 11 is a diode that keeps the polarity of the signal constant; 1? 1 is an incoming circuit that generates an incoming drive signal from an incoming signal; 14 is a speaker that plays a ringtone; 15 is a variable resistance circuit that changes the ringtone; 16 is a microphone that collects ambient noise; 17 is a microphone 18 is a control circuit that controls the resistance value of the variable resistance circuit 15 in accordance with the ambient noise level.

Next, the operation of this embodiment will be explained. The microphone 16 collects ambient noise, and outputs a signal corresponding to the noise level to the control circuit 18 after being digitized by the A/D conversion circuit 17 . The control circuit 18 controls the variable resistance circuit 15 to take a resistance value corresponding to the input noise level. The method of control at this time is, for example, by setting level 1 and level 2 in the control circuit 18 as shown in FIG. Accordingly, a resistance value (R1 or R2 or R3) is selected, and the variable resistance circuit 15 is controlled to take the selected resistance value. On the other hand, an incoming signal input from the office line 10 via the diode bridge 11 becomes an incoming drive signal in the incoming circuit 12, and is output to the speaker 14 via the variable resistance circuit 15. At this time, the incoming drive signal is transmitted to the variable resistance circuit 15.
Since the ring tone is attenuated by the resistance value of the variable resistance circuit 15 and output to the speaker 14, the ring tone is outputted from the speaker 14 at a level corresponding to the resistance value of the variable resistance circuit 15. 2. According to this embodiment, the control circuit 18 automatically sets the ringing level of the ringtone corresponding to the surrounding noise, so that the ringtone can always be sounded clearly and at an appropriate volume.

FIG. 3 is a block diagram showing another embodiment of the present invention. This example applies the present invention to a button telephone.
Reference numeral 21 indicates a key telephone main device, and 22 indicates a key telephone. Button phone main unit @21 is Crosspoint 211,
It consists of an incoming call detection circuit 212, a tone linker circuit 213, and a control circuit 214.

The button telephone 22 includes a ringtone ringing circuit 221, a variable resistance circuit 222, a terminal control circuit 223, and an A/D conversion circuit 2.
24 and a microphone 225.

Next, the operation of this embodiment will be explained. button phone 2
2, the ambient noise collected by the microphone 225 is input to the A/D
It is digitized by the conversion circuit 224 and input to the terminal control circuit 223. The terminal control circuit 223 changes the resistance value of the variable resistance circuit 222 according to the input noise level. On the other hand, when an incoming signal is input from the office line 23,
The incoming call detection circuit 212 detects this and notifies the control circuit 214. As a result, the control circuit 214 controls the cross point 211 to connect the office line 23 and the key telephone 22. The incoming call signal is sent from the ring tone ringing circuit 22 of the button telephone 22.
1 and becomes an incoming drive signal, and this incoming drive signal is amplified by a loudspeaker (not shown) such as a sounder or a speaker via a variable resistance circuit 222. At this time, the level of the ringtone amplified by the loudspeaker is determined by the resistance value of the variable resistance circuit 222. Similarly, when a call is received from another telephone of the button telephone device, the control circuit 214 controls the cross point 211 to connect the button telephone 22 and the tone ringer circuit 213.

The ring tone from the tone ringer circuit 213 is sent to the ring tone sounding circuit 221 via the cross point 211, where it becomes an incoming call drive signal and is output to the loudspeaker via the variable resistance circuit 222. In this case as well, the level of the ringing sound from the loudspeaker is determined by the resistance value of the variable resistance circuit 222.

As described above, in this embodiment, the ringing level of the ringtone is automatically adjusted by the terminal control circuit 223 according to the surrounding noise, and the same effect as in the previous embodiment is achieved.

[Effects of the Invention] As described above, the telephone ringing circuit of the present invention has the advantage that the volume of the ringing tone can always be automatically adjusted to an appropriate level according to the level of ambient noise.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the ringtone ringing circuit for a telephone according to the present invention, FIG. 2 is an explanatory diagram of the operation of the control circuit shown in FIG. 1, and FIG. 3 is a diagram showing another embodiment of the present invention. FIG. 4 is a block diagram showing an example of a conventional telephone ringing circuit. 12... Incoming circuit, 14... Speaker 15.222
...variable resistance circuit, 16,225 microphones 17, 22
4... A/D conversion circuit, 18... Control circuit 21...
・Key telephone main device, 22...Key telephone 221・
...Ring tone circuit? 23...Terminal control circuit agent Patent attorney Nori Ken Chika Kanshu Sanno - ○ R1 Level 1- 〇 R2 Fig. 2 21 22 Bofun 1 Via Kotoki X Fig. 3

Claims (1)

[Claims] In an incoming ringing circuit that generates an incoming drive signal from an incoming signal input from a central office line, etc. and outputs it to a loudspeaker to sound a ringtone, an attenuation device that attenuates the incoming drive signal and outputs it to the loudspeaker. A sound collecting means for collecting ambient noise and inputting a noise signal, and a control means for changing the attenuation rate of the attenuation means according to the level of the input noise signal. Telephone incoming ringing circuit.