JPS6321200B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sound generation circuit for a sound clock that electrically generates an alarm sound and a time signal sound.

Traditionally, the sound of a bell is often used as an alarm sound or time signal sound in clocks, and in the sound circuit of a clock that emits a bell sound electrically, the convoluted line of the acoustic waveform has an index having a single time constant. Functions are used.

On the other hand, the clasp of an actual bell sound has a shape that oscillates and attenuates, and the clasp line differs depending on the frequency components contained in the bell sound. Therefore, the sound of the bell emitted by the conventional sound signal circuit is extremely lacking in richness and resonance. The present invention includes a discharge circuit including a first transistor that controls charging of a capacitor and a second transistor that controls discharging of the capacitor, and applies a charging pulse to the input terminal of the second transistor, and By applying a modulation pulse to the transistor, the discharge current flowing through the discharge circuit is controlled, and as a result, an attenuated waveform containing an alternating current component based on the modulation pulse is generated at the terminal of the capacitor, and the waveform is By using the sound waveform as a convoluted line of the sound waveform of the sound signal, a sound generation circuit which emits a tone closer to the actual sound of a bell is provided.

This will be explained below based on the drawings. FIG. 1 shows a conventional circuit. A is a conventional entangled line generation circuit diagram, B is an input/output waveform diagram, and charging pulse 7 is applied to input terminal 1.
is applied, the transistor 3 becomes conductive by the inverter 2, and the capacitor 4 is charged. When the charging pulse 7 stops, the capacitor 4 becomes the resistor 5.
As a result of discharging through the output terminal 6, an exponentially decaying sawtooth wave 8 appears at the output terminal 6.

Figure 2 shows an embodiment of the present invention in which a capacitor is discharged intermittently to create an attenuated entanglement line containing an alternating current component. is the input/output waveform diagram, and Figure 2A is the first waveform diagram.
A transistor 9 is added in series with the resistor 5 of the circuit shown in FIG. In this circuit, the transistor 9 controls the discharge current flowing from the capacitor 4 to the resistor 5 in accordance with the modulation pulse shown in 11 in FIG. As a result, the output terminal 12 has an attenuated waveform 2 containing an AC component.
1 appears. FIG. 2B shows an example of the configuration of a circuit having the same effect as the circuit shown in FIG. When the battery is charged and the charging pulse stops, it is intermittently discharged via the transistor 16 and the resistor 17 in accordance with the entanglement line modulation pulse 11 shown in FIG.

Figure 3 shows an embodiment of the present invention that creates an attenuating entangled line containing an alternating current component by changing the discharge resistance of a capacitor, and Figure 3 A, B, and C are circuit configuration diagrams of the present invention. , Figure 3D is a waveform diagram, and Figure 3A is the capacitor 4 in the circuit example shown in Figure 2A.
A resistor 22 is connected in parallel with the capacitor 4, and the capacitor 4 is connected in parallel with the resistor 22, and the capacitor 4 is connected in parallel with the resistor 22 and via the resistors 22 and 5. As a result of the alternating discharge, a waveform shown in FIG. 3D appears at the output terminal 12, which oscillates and attenuates. In FIG. 3B, the capacitor 4 is switched by the transistor 9 between discharging via the resistors 23 and 5 in series and discharging via the resistor 21.
The output 24 has an attenuating waveform 24 containing an AC component.
appears. FIG. 3C shows the circuit shown in FIG.
resistor 2 by the entanglement modulation pulse applied to 8
As a result of the alternating discharge through resistor 5 and resistor 25 and resistor 17 in parallel, an attenuating waveform containing an alternating current component appears at output terminal 26 as shown in FIG. As described above, the circuit diagrams A, B, and C shown in FIG. 3 have exactly the same effect.

FIG. 4A shows an embodiment of a circuit that uses two capacitors and periodically shorts the terminals of the capacitors to generate an attenuating entangled line containing an alternating current component. The operation of this circuit will now be explained step by step. The charging pulse 7 applied to the input terminal 30 causes the transistors 31 and 32 to become conductive, and the capacitors 33 and 34 to be charged. When the trigger pulse 7 stops, the capacitor 34 is discharged via the resistor 35, and the capacitor 33 is discharged from the transistor 3.
6 intermittently charges and discharges the capacitor 34 via the resistor 37 in accordance with the modulation pulse 11, and as a result, an attenuating waveform 39 containing an alternating current component appears at the output terminal 38. (Figure 4B shows input and output waveforms.) Even if a resistor 40 is added in parallel with the capacitor 33, the effects of the present invention do not change. Even if the resistor 41 is added between the terminals of the capacitors 33 and 34, the effects of the present invention do not change.

FIG. 5 is a block diagram of a circuit according to the present invention which uses the present invention shown in FIGS. 2 to 4 to synthesize the waveform of a bell tone by adding sounds of different frequencies having different entangling lines. Show diagram. In FIG. 5, 51, 52, 53, 54 are generating circuits for attenuating entangled lines containing alternating current components according to the present invention, 50 is a charging pulse input terminal, 61, 62, 6
3 and 64 are tangle modulation input terminals. 56,5
Acoustic signal modulators 7, 58, and 59 amplitude-modulate the acoustic signals applied to input terminals 66, 67, 67, and 68 using the output signals of 51, 52, 53, and 54. 60 is a mixer and modulator 5
It has a function of adding inputs from 6, 57, 58, and 59. 61 is an amplifier, and mixer 60
The sounding body 62 is driven by the output waveform.

As described above, according to the present invention, it is possible to generate tone waveforms of different frequencies having different attenuation states, and to produce a clock that emits a warning sound that does not feel strange compared to the actual sound of a bell. Can be done.

FIG. 6 shows an embodiment of a circuit for generation, amplitude modulation, and mixing of entangled lines. Transistors 75, 76,
77, 95, 96, 97, and resistors 120 and 121 control charging and discharging of capacitors 74 and 94, and resistor 8
0, 81, 100, 101 are transistors 72, 73 of the acoustic signal amplitude modulation circuit that also serve as discharge resistors;
92 and 93 are load resistances. 82,8
3, 102, and 103 constitute a mixer, and 110 is an output terminal. A charging pulse is applied to input terminals 70 and 90, an entangling line modulation pulse is inputted to input terminals 71 and 91, and acoustic frequency input terminals 72, 73 and 9 are input.
When, for example, two-phase pulses are applied to the output terminals 2 and 93, an acoustic waveform of a bell accompanied by a beat is outputted to the output terminal 110. Acoustic frequency input terminals 72, 7
Even if pulses input to 3, 92, and 93 have different frequencies and duties, a bell acoustic waveform is output to 110. The resistor 105 short-circuits the capacitors 74 and 94, and converts the frequency components input to the input terminals 72, 73, 92, and 93 into the output waveform appearing at 110 even when the charging pulses input to the input terminals 70 and 90 have different timings. For example, when charging pulses are input alternately to input terminals 70 and 90, 72, 73, 92, 9
As a result of the superimposition of the frequencies input into 3, the sound becomes richer than that containing a single frequency component. According to this configuration circuit, a bell sound with a beautiful tone can be easily synthesized using a small number of circuit elements.

In addition, the input terminals 72, 73, 92, 93 have terminals 7
Although an entanglement modulation signal different from the input of 1.91 may be input, the acoustic signal frequency is in the audio frequency range, and the entanglement modulation frequency can be 2 to 50 Hz.

[Brief explanation of the drawing]

Figures 1A and 1B are a circuit diagram of a tangled line generation circuit and a waveform diagram showing the tangled line of a sound signal in a conventional sound signal circuit;
Figures 2A and 2B are circuit diagrams for generation of signal tone entanglement lines in the present invention, Figure 2C is input and output waveform diagrams, and Figure 3A, B, and C are respective entanglement lines of the signal tone in the present invention. Figure 3 D is an input and output waveform diagram, Figure 4 A is a signal generation circuit diagram of the present invention, Figure 4 B is an input and output waveform diagram, and Figure 5 is the present invention. FIG. 6 is a block diagram of the alarm tone generating circuit of the present invention, which performs tangential line generation, amplitude modulation, and mixing. 3, 14...first transistor, 9, 15...
...Second transistor, 16...Third transistor, 4,12...Capacitor.

Claims (1)

[Claims] 1. In an alarm clock that electrically emits an alarm sound or a time signal sound, a first transistor and a first capacitor are connected in series from the power supply side to the ground side.
a second charging circuit consisting of a second transistor and a second capacitor in series from the power supply side to the ground side, and a third transistor and a resistor between the first and second capacitors. 1. A sound generating circuit comprising: a short circuit control circuit; and a discharge circuit comprising a resistor connected in parallel with the second capacitor.