JPS5928473Y2 - sound device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a sounding device using an electromagnetic buzzer.

Although electromagnetic buzzers are small and lightweight, they have a high sound pressure and have high notification capabilities. At the same time, they can emit arbitrary notification sounds by controlling the drive current waveform, so they are used in various electronic devices. It is being applied to

Naturally, the notification with this electromagnetic buzzer relies on sound, and to increase the notification power it relies on visual perception.

That is, it is conceivable to operate the light emitting elements at the same time.

As this light emitting element, it is preferable to use a light emitting diode (LED) such as GaP from the viewpoint of power consumption and miniaturization.

On the other hand, there are currently only LEDs that do not light up unless a voltage of 2.2 V or higher is supplied.

However, since sound generating devices based on electromagnetic buzzers are built into wristwatches, etc., the driving voltage depends on one silver oxide battery.
．． Approximately 5V is used.

Therefore, it was not possible to directly light the LED using the power source battery of the sound generating device.

This invention was made in view of these points,
The details are explained below.

FIG. 1 is an electrical circuit diagram of the sound generating device of the present invention, 1.2
is a directly connected drive transistor, and is provided with a positive feedback circuit 5 consisting of a series circuit of a resistor 3 and a capacitor 4.

6 is an electromagnetic laser connected to the collector circuits of the drive transistors 1 and 2, for example, 0.08771771Φ.
A coil of 330 turns is wound inside a pot-shaped core, and a magnetic plate with a diameter of 12M is placed opposite to this coil.

7 is an LED such as G a P%, which is connected in parallel to this electromagnetic buzzer 6 and in a direction to absorb the back electromotive force generated by energizing the buzzer 6, and it emits light only at 2.2V or more. The light is also ()).

8 is a bias resistor connected to the base of the drive transistor 1゜2, 9 is a power supply battery, such as a silver oxide battery or AA battery.
．． It consists of one battery of approximately 5V, and is configured to supply power to the sound generation circuit via the operation switch 10.

By turning on the operation switch 10, power is supplied to the drive transistors 1 and 20 through the bias resistor 8, so that the transistors 1 and 2 perform an oscillating operation in cooperation with the feedback circuit 5. When the oscillation signal starts, the electromagnetic buzzer 6
This buzzer 6 starts sounding operation.

At the same time, as current flows through the electromagnetic buzzer 6, a back electromotive force is generated due to its inductance component, and since the back electromotive force is in the forward direction with respect to the LED 7, this I, E
The signal flows to D7 and absorbs the influence on the drive transistors 1 and 2.

On the other hand, the back electromotive force generated across the electromagnetic buzzer 60 at this time is caused by the high frequency of the current flowing through the electromagnetic buzzer 6 of about 2 to 3 KH, the inductance value being small, and the flowing current being relatively large. Light emission voltage of 2.2V
As a result, the LED 7 lights up.

FIG. 2 shows another embodiment of the present invention. The one in FIG. 1 emits light continuously only while the operating switch 10 is ON, but this embodiment emits light only when the operating switch 10 is ON.
The light will emit light intermittently during the period.

The difference from FIG. 1 is that a charging/discharging circuit 13 is added to the base of the drive transistor 1.2, with a resistor 11 and a capacitor 12 connected in series. When the switch 10 is turned on, the transistors 1 and 2 perform an intermittent oscillation operation, and accordingly the electromagnetic buzzer 6 generates an intermittent sound, and at the same time, the LED
7 also emits light intermittently.

In order to notify the viewing room by lighting the LED at the same time as the electromagnetic buzzer sounds, as shown in FIG. As the battery 9, it was necessary to use a battery of 3 or more square meters, in which two or more silver oxide batteries were connected in series.

In contrast, the present invention uses an LED in a die hood that absorbs the back electromotive force generated by the electromagnetic buzzer, and uses the back electromotive force to light up the LED, so the power source battery is limited to the light emission voltage of the LED. It is possible to use a low-voltage device that does not generate electricity, making it possible to downsize the sounding device, and also eliminating the need for a diode to absorb back electromotive force, which was originally necessary, reducing the number of parts and contributing to cost reduction.
The rollers are also big.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of the sound generating device of the present invention, FIG. 2 is an electric circuit diagram showing another embodiment of the same device, and FIG. 3 is an electric circuit diagram showing a conventional example, in which 192 is a driving transistor; 5 is a positive feedback circuit, 6 is an electromagnetic buzzer, 7 is an LED, 9 is a power source battery, 10 is an operation switch, and 13 is a charging/discharging circuit.

Claims (1)

[Scope of utility model registration request] In a sounding device that drives an electromagnetic buzzer using an oscillation transistor equipped with a positive feedback circuit, a voltage lower than the light emitting voltage of a light emitting diode is supplied to the sounding device, and a voltage is applied to the buzzer in parallel to the electromagnetic buzzer. A light emitting device is characterized in that a light emitting diode is connected in a direction to absorb a back electromotive force generated by energization, and the light emitting diode is lit by the back electromotive force generated when the electromagnetic buzzer sounds.