JPS6033765A - Tone ringer circuit - Google Patents

Abstract

PURPOSE:To identify easily incoming display not only by the difference in ring tone period but the change in tone color by discriminating each length of transmission intervals of a call signal transmitted from an exchange station, thereby changing the frequency of an audible signal. CONSTITUTION:When a call signal is supplied between telephone set terminals 1a and 1b, the signal is converted into a DC voltage corresponding to the intermission of the call signal by a DC block capacitor 2, rectifier bridge 3 and a smoothing capacitor 4. The level of a terminal voltage of the capacitor 4 is changed intermittently in response to the intermittent period of the call signal, and the speed of the period is discriminated, either state is outputted to an oscillating frequency selecting circuit 7 from a terminal 5a and also a gate circuit 6 is driven from a terminal 5b to decide and hold the oscillating frequency, and the result is outputted from a speaker 9 via an amplifier circuit 8 as an audible tone.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tone ringer circuit used in telephones and the like.

Conventionally, this type of tone ringer circuit simply intermittents a single audible wave number corresponding to the sending interval of the incoming and outgoing signals sent from the switching center, and generates an audible sound using an electroacoustic transducer such as a speaker. It was intended to be generated. For this reason, switching stations, especially PBXs, etc., change the sending interval of the paging signal for the incoming call type service, for example, depending on whether an external call is received or an extension call is received.
The system allows the user to identify whether an incoming call is coming from an outside line or an internal line, but this is inconvenient because it is difficult to distinguish because the interval between the ringtones simply changes. be.

The purpose of the present invention is to solve the above-mentioned inconvenience, and to make it possible to easily determine the type of incoming call by determining the length of the sending interval of call No. 16 sent from the switching center, and changing the frequency of the audible signal based on this. The purpose of the present invention is to provide a tone ringer circuit that provides a tone ringer circuit that provides a tone ringer circuit that provides a tone ringer circuit that provides a tone ringer circuit that provides a tone ringer circuit that provides a tone ringer circuit that can be used as a tone ringer.

The tone ringer circuit of the present invention converts the audible frequency (fi) obtained by rectifying and smoothing the ringing signal sent from the switching station into an audible tone "C" to an electroacoustic transducer and displays the incoming call. an oscillation frequency circuit that selects from different oscillation frequencies according to the output of the interval discrimination circuit and outputs it to the electroacoustic transducer; The present invention is characterized by comprising a gate circuit that operates on the output and disables the operation of the oscillation frequency selection circuit until the interval discrimination circuit completes discrimination.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, and FIG. 2 shows signal waveforms at various parts thereof.

Referring to FIG. 1, this embodiment has telephone terminals la, 1b.
+ DC blocking condenser ridge 3. Smoothing capacitor 4. An oscillation frequency selection circuit 7 including an interval discrimination circuit 5, a gate circuit 69 and an oscillation circuit. It is composed of an amplifier circuit 8 and a speaker 9.

When a ringing signal is applied between telephone terminals 1a-lb,
DC blocking capacitor 2. The rectifier bridge 3° smoothing capacitor 4 converts the signal into a DC voltage corresponding to the intermittent calling signal. That is, normally, the calling signal from the exchange is 16
A Hz signal is sent for 1 second and the sending is stopped for 2 seconds.Also, in the case of special incoming call identification, the cycle is set to 1/4 without changing this ratio.
A common method is to change the Therefore, the level of the terminal voltage of the smoothing capacitor 4 changes intermittently in accordance with the intermittent cycle of the calling signal as shown in FIG. , distinguish between fast and slow cycles,
One of these states is held in a latch circuit, the output is outputted to the oscillation frequency selection circuit 7 from the terminal 5a, and the gate circuit 6 is driven and turned ON via the output terminal 5b at the second time of the level change period. Through the operation of the discrimination circuit 5, the oscillation frequency is determined and held, and the oscillation frequency selection circuit 7 is driven to oscillate, which is converted into an audible sound by the speaker 9 via the amplifier circuit 8, and incoming call display identification is performed. In FIG. 2, the output voltage of the interval discrimination circuit 5 is output in the second cycle of the calling signal, but the voltage is output at the terminal 5a only when the cycle is fast or short. . Further, the output voltage of the oscillation frequency selection circuit 7 starts to oscillate at the selected frequency from the second period of the calling signal, and thereafter the oscillation is intermittent according to the period of the calling signal.

Next, when the calling signal disappears and a certain period of time has elapsed, the interval determining circuit is reset to the initial state. Note that it is also conceivable that this reset be performed when the first paging signal arrives. Moreover, the oscillation frequency selection circuit 7 includes a C-oscillator circuit, a multivibrator circuit,
This can be easily realized by using an LC oscillation circuit or the like, and using an analog switch or the like to select the 08 time constant for C in the former two cases, and to select the capacitor in the latter case.

According to the present invention, as explained above, incoming call display identification is facilitated by changing the tone of the ringing cycle.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a waveform diagram showing signal waveforms at various parts in FIG. la, lb...telephone terminal, 2...DC blocking capacitor, 3...rectifier bridge, 4...
... Smoothing capacitor, 5 ... Interval discrimination circuit, 6° mark gate circuit, 7 ... Oscillation frequency selection circuit, 8 ... Amplification circuit ,9...
...Speaker.

Claims (1)

[Claims] In a tone ringer circuit that displays an incoming call as an audible sound using an electric sound transducer using an audible frequency signal obtained by rectifying and smoothing a calling signal sent from a conversion station, the sending interval of the calling signal sent from the switching station is determined. and an interval discrimination circuit to determine the temperature according to the output of this interval discrimination circuit
a frequency selection circuit that selects from mutually different oscillation frequencies and outputs it to the electroacoustic transducer; and a frequency selection circuit that operates on the output of the interval discrimination circuit, and disables the operation of the oscillation frequency selection circuit until the interval discrimination circuit completes discrimination. A tone ringer circuit characterized by comprising a gate circuit that performs the following steps.