JPH0426256A - Cordless key telephone system - Google Patents

Abstract

PURPOSE:To discriminate an incoming sound from the other ones by using a buzzer with the peak of resonant sensitivity in two frequency positions as the sounding body of a mobile radio telephony equipment and generating more than two different frequency incoming sounds with the peak of sensitivity by the buzzer when doorphone incoming call is received. CONSTITUTION:When receiving the doorphone incoming call, signals with frequency f1 and f2 are alternately supplied to the base of a transistor 43 with duration T1 and T2 respectively from a terminal FQ of a control circuit 46. On the other hand, a terminal ENV of the control circuit 46 is in the state of 'low bell' during the ringing period of each duration of T1 and the first half of T2, and 'high-impedence' during the last half of envelope. In this way, the envelope whose frequency f1 and f2 becomes gradually getting smaller, is added in the envelope period, and the doorphone incoming sound, similar to a chaim sound as the intercom sound by the two sounds of frequency f1 and f2, is obtained. Thus, the doorphone incoming sound can be easily discriminated from the other incoming sound such as inner line incoming sound even when it is the buzzer.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a cordless button telephone device that also functions as a doorbell, and particularly relates to a method of emitting a ring tone when a call is received by the doorphone.

[Conventional technology]

2. Description of the Related Art Key telephone devices having a doorbell function have been known for some time. For example, a doorbell terminal equipped with a call button, a microphone as a transmitter, and a speaker as a receiver is installed at the front door of a residence, and the voice line and control line are connected between the doorphone terminal and the main device. It is possible to make a call between the doorbell terminal and a terminal telephone connected to the main device. In this type of button telephone device, when a call button on the doorphone terminal is pressed, a doorphone ringing tone is emitted by a sounding body in the terminal telephone. In this case, in order to distinguish the incoming call from the doorphone from other incoming calls, such as an incoming call from an extension (own call), it is necessary to make the ringtones distinguishable. FIG. 5 shows a ring tone generation circuit in a conventional terminal telephone. Conventionally, the terminal telephone is a wired telephone, and the wired telephone is equipped with a speaker 1 as a sounding body. and,
A self-ringing sound source 2 and a doorbell ringing sound source 3 are provided, respectively. The self-ringing sound source 2 generates a single-frequency intermittent audio signal. On the other hand, the intercom ring tone sound source 3 synthesizes sounds of two different frequencies by applying envelope control to generate an audio signal of a so-called "ping-dong" sound. Under the control from the control circuit (CPU) 5 of the terminal telephone, the self-ringing tone sound source 2 is driven when the internal call is on, and the doorbell ringing tone sound source 3 is driven when the doorphone is incoming, and the audio signal of each ringtone is driven. is supplied to the speaker 1 via the power amplifier 4,
Each ringtone is emitted.

[Invention or problem to be solved]

Incidentally, recently, cordless button telephone devices using mobile radio telephones as terminal telephones have been provided. When this cordless button telephone device is provided with a doorbell function, the doorphone ringing tone is emitted from the mobile radio telephone. Mobile radio telephones are generally small and thin, and it is difficult to use a speaker as a sounding device, so a buzzer is usually used. Therefore, the conventional ring tone generation circuit shown in Fig. 5 can be used as is in a ring tone generation circuit using a buzzer of a mobile radio telephone. It may be possible to generate the ringtone by changing the ringing cycle to distinguish it from other ringtones. However, simply changing the ringing cycle has the disadvantage that it is difficult to distinguish the ringtone from other ringtones. In addition, a speaker is used as a sounding body in a mobile radio telephone,
Even if the ringtone generation circuit shown in Fig. 5 is used, the conventional ringtone generation circuit
The ring tone generation circuit shown in the figure requires separate sound sources 2 and 3 for each of the self-ringing tone and the doorbell ringing tone, so it is expensive and requires a large circuit space. In view of the above points, the present invention provides a cordless button telephone device in which it is easy to distinguish the doorbell ringtone from other ringtones even if a buzzer is used as a sounding body of a mobile radio telephone as a terminal telephone. The purpose is to

[Means to solve the problem]

The present invention is a cordless button telephone device that uses a mobile radio telephone as a terminal telephone and is capable of answering an incoming call from a doorbell terminal using the mobile radio telephone, the mobile radio telephone having at least two frequency positions as a sounding body. , a buzzer having a resonance sensitivity peak is used, and when a doorbell call is received from the doorphone terminal, the buzzer generates a doorbell ring tone using two or more different frequencies having a sensitivity peak. The ringtone is different from other ringtones.

[Function] When a doorbell call is received, the buzzer, which is the sounding body of the mobile terminal phone, is driven so that it generates a doorbell ringing tone, for example, "pin bone", which uses two frequencies with peak resonance sensitivity. do. This makes it easy to distinguish between a buzzer or other ring tones that use a sound of one frequency having a resonance sensitivity peak, such as a self-ringing tone, and a doorbell ring tone. Embodiment An embodiment of the cordless button telephone device according to the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram of an embodiment of the cordless button telephone device according to the second example. A mobile radio telephone that is wirelessly connected to the device is provided corresponding to each fixed radio device, and data transmission between the main device and the main device to realize the functions of the key telephone device such as inter-extension calls is carried out by the fixed wireless device. Communication between the mobile radio telephone and the fixed radio equipment is carried out between the mobile radio telephone and the fixed radio equipment: call signals and outgoing calls. Simple state transition information such as end of call, lamp flashing information, push button operation information, etc. are transmitted and received. In FIG. 2, 10 is a main device, which includes a voice switch circuit 11, a central office line interface circuit 12, a door phone interface circuit 13, extension line interface circuits 14a and 14b, and a microcomputer to control these. It consists of a circuit 15. Two or more extension interface circuits may be provided. A telephone line 16 is connected to the office line interface circuit 12 . Although this example accommodates one telephone line, it goes without saying that the main device 10 can accommodate multiple lines. Reference numeral 20 denotes a door phone terminal, which includes a door phone call button 21, a microphone 22 and a speaker 23, a microphone amplifier 24 and a speaker amplifier 25, a telephone interface circuit 26, and a control circuit 27 equipped with, for example, a microcomputer. The telephone interface circuit 26 and the doorphone interface circuit 13 of the main device 10 are connected by an audio line 28, and the control circuit 27 and the control circuit 15 of the main device 10 are connected by a doorphone control line 29. Ru. Fixed wireless devices 30a and 30b are connected to the main device 1o by a communication line 31a and a data line 32, a communication line 31b and a data line 32, and the fixed wireless device 30a
and 30b and the main device ] 0, it is configured to transmit data and send and receive call signals. That is, although each of the fixed wireless devices 30a and 30b is not equipped with a handset, a dial button, a hook switch, or other operation parts, it is equipped with the same data transmission circuit as a so-called conventional button telephone, and furthermore, a wireless color transmitting/receiving circuit. This is provided. Mobile radio telephones 40a and 40b are configured to form a radio line in correspondence with the fixed radio devices 30a and 30b, respectively, and are provided with a radio transmitting/receiving circuit, an operation section, and the like. The mobile radio telephones 40a and 40b are equipped with a buzzer as a sounding body, and the buzzer emits each ring tone such as an incoming call from an extension or an incoming call from an intercom. The fixed wireless devices 30a and 30b can mutually form a communication path by transmitting data with the main device 1°. That is, the call signals and state transition signals such as call origination and call termination are sent and received from the fixed wireless devices 30a and 30b to the mobile radio telephones 40a and 40b, respectively, through the radio lines, and the extension intercommunication between the mobile radio telephones 40g and 40b, Since complex data processing with the main device 10 for selective calls to outside lines is not performed via the wireless line, it is possible to realize a highly functional cordless button telephone device. In the cordless button telephone device configured as described above, when there is a calling operation from the doorphone terminal 20, the following occurs. That is, when the call button 21 is pressed on the doorphone terminal 20, a double signal is also output to the doorphone control line 29 via the control circuit 27. The control circuit 15 of the main device 10 receives this incoming signal and
It is determined that there is a doorbell call from the doorphone terminal 20, and the fixed wireless devices 30a and 30 are connected via the data line 32.
Sends a doorbell incoming request to b. The fixed wireless devices 30a and 30b send a doorbell (3 request) to the mobile wireless telephones 40a and 4(]b. The mobile wireless telephones 40a and 40b emit a doorbell ringing tone, which will be described later, using their buzzers. When the telephone is answered, the main device 1o operates the doorphone interface circuit 21 and connects the doorphone control line 2.
9, a response signal is sent to the doorphone terminal 20. The door phone terminal 20 causes the telephone interface circuit 26 to function the microphone amplifier 24, the microphone 22, the speaker amplifier 25, and the speaker 23 under the control of the control circuit 27, and sends an audio signal to the audio line 28. Also, main device] 0
A voice signal from the mobile radio telephone that responded is sent to the voice line 28, and a mutual conversation is established. In this example, the above-mentioned doorbell ringtone uses two types of sounds so that it can be distinguished from an extension call, which is a single intermittent tone. FIG. 1 shows an embodiment of a ring tone generation circuit provided in mobile radio telephones 40a and 40b. In the figure, 41 is a buzzer, which has a frequency f
The resonance sensitivity has peaks at two frequency positions: 1 and a higher frequency f2. In this case, the buzzer 41 is connected to the mobile radio telephones 40a, 40b.
For example, f, -2kH when installed in the housing of
z, f2-2.6kHz. A power supply terminal from which a positive DC voltage +V is obtained is connected to the emitter of the transistor 42, and its collector is connected to one end of the buzzer 4. Further, the other end of the buzzer 41 is connected to the collector of a transistor 43, and its emitter is grounded. Then, the base of the transistor 42 and C
Enherobe control terminal E of the control circuit 46 with PU
A time constant circuit consisting of a resistor 44 and a capacitor 45 for envelope control is connected between the NV and NV. Further, the oscillation frequency control terminal FQ of the control circuit 46 is connected to the base of the transistor 43. The operation of this ringtone generation circuit will be explained below. When the buzzer 41 emits an extension tone, the enherobe control terminal ENV of the control circuit 46 is always at a low level, a constant base current flows through the transistor 44, and the transistor 44 becomes conductive. Then, from the oscillation frequency control terminal FQ of the control circuit 46, a signal of frequency f is intermittent at a predetermined period and supplied to the base of the transistor 43, and the buzzer 41 emits the sound of frequency f1 according to the intermittent period. A sound is emitted periodically. In addition, when a doorbell call is received, each terminal EN of the control circuit 46
V and FQ are controlled as shown in FIG. That is, from the terminal FQ of the control circuit 46, the frequencies f,
and the signal with frequency f2, respectively, have a duration T1
and T2 are alternately supplied to the base of transistor 43. On the other hand, the terminal E N V of the control circuit 46 is
The ringing periods a and a2 in the first half of T1 and T2 are at low level, and the second half envelope periods b1 and a2 are in a high impedance state. Therefore, during the ringing periods a1 and a2, the transistor 4
Since the base current of No. 2 is constant, the buzzer 41 rings with a sound corresponding to each frequency and with a predetermined loudness. In addition, the envelope period S and b2 have the same impedance as the terminal ENV, so the resistor 44
The base current of the transistor 42 flows into the capacitor 44 through the capacitor 44 . As this capacitor 45 is charged, the base current becomes smaller, and the current flowing through the buzzer 41 also becomes smaller. Therefore, the sound of the buzzer 41 becomes smaller as the current decreases. Thus, during the envelope period and b2, the frequency f
1 and f2 are applied with an envelope that gradually becomes smaller, and the two tones of frequencies f1 and f2 produce a doorbell ringing tone resembling a chime sound. FIG. 4 is an example of a flowchart of the control operation of the control circuit 46 of this ring tone generation circuit. In addition, in the above example, a buzzer having resonance sensitivity peaks at two frequencies f and f2 is used, or if a buzzer having resonance sensitivity peaks at two or more frequency positions is used, the buzzer having resonance sensitivity peaks at two or more frequency positions is used. Sound may also be used to form a doorbell ringtone.

【Effect of the invention】

As explained above, the present invention provides a cordless hotane telephone device that uses a mobile radio telephone as a terminal telephone, which uses a buzzer as a sounding body, and generates a doorbell ring tone using a sound at the peak frequency of two or more resonance sensitivities of the buzzer. Therefore, even if it is a buzzer, it can be easily distinguished from other ring tones such as an extension ring tone. Therefore, it is possible to obtain a doorbell ringtone that is easily distinguishable from other ringtones without using a speaker as a sounding body, contributing to miniaturization and thinning of mobile radio telephones. In addition, it is possible to obtain a doorbell ringtone that can be distinguished from other ringtones without having to separately provide a sound source for the doorbell ringtone and a sound source for other incoming calls, as in the past, so it can be manufactured at low cost. At the same time, the circuit space is also reduced.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an example of the main part of this invention, and FIG.
A block diagram of an example of the cordless button telephone device of the present invention, FIG. 3 is a timing chart for explaining the example in FIG. 1, FIG. 4 is a flow chart for detailed explanation of the present invention, and FIG. 5 is a conventional FIG. 2 is a block diagram of an example of a ringtone generation circuit of FIG. 10; Main device 13; Door phone interface circuit 14a, 14b; Extension interface circuit 15; Control circuit 20: Door phone terminal device 40a, 40b; Mobile radio telephone section 46: Control circuit for forming ring tone

Claims (1)

[Scope of Claims] A cordless button telephone device that uses a mobile radio telephone as a terminal telephone and is capable of responding to incoming calls from a door intercom terminal using the mobile radio telephone, the mobile radio telephone having at least two speakers as sounding bodies. A buzzer having a resonance sensitivity peak is used at a frequency position, and when a doorphone call is received from the doorphone terminal, the buzzer generates a doorphone ringing tone using two or more different frequencies having a sensitivity peak. A cordless button telephone device that is driven in such a way that it can be distinguished from other ringtones.