JP2582893Y2 - Siren drive circuit - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a siren driving circuit, and more particularly to a siren driving circuit suitable for a car security system.

[0002]

2. Description of the Related Art FIG. 2 shows an example of a driving circuit for a siren of a conventional car security system. As shown in the figure, +
The B terminal is connected to the + terminal of the battery 8 via the series circuit of the diode 10 and the resistor 9 and the diode 11, and the GND terminal is connected to the − terminal of the battery 8.

One terminal of a speaker 4 is connected to a + B terminal, and the other terminal is connected to a GND terminal via a transistor 3 and a transistor 2. Oscillator 1 +
The −side power supply terminal is connected to the + B terminal, and the −side power supply terminal is connected to the GND terminal via the transistor 2.

[0004] The output signal terminal of the oscillator 1 is connected to the base of the transistor 3. Further, the base of the transistor 2 is connected to a ring control terminal.

In the above configuration, the + B terminal and the GND terminal are connected to the vehicle battery, and the current supplied from the vehicle battery is charged to the battery 8 through the series circuit of the diode 10 and the resistor 9.

The sound control terminal is connected to a siren control terminal of a car security system. When the siren control terminal goes high with respect to the GND terminal, the transistor 2
Is turned on, power is supplied to the oscillator 1, the output of the oscillator 1 is amplified by the transistor 3, and the speaker 4 is sounded.

When the siren control terminal goes low with respect to the GND terminal, the transistor 2 is turned off and the oscillator 1
No current is supplied to the speaker 4 and the speaker 4 does not sound.

[0008]

Problems to be Solved by the Invention In the above-mentioned conventional siren drive circuit, a ring for sound control is required in addition to two power supply lines for charging, and a total of three wirings are required. Become. When used as a car security system,
This has increased the cost of the body harness and increased the wiring man-hour.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide a siren drive circuit capable of controlling charging and sounding of a battery with a total of two wires. It is in.

[0010]

According to the present invention, there is provided a siren driving circuit for charging a battery by a power supply line and turning on / off a current supplied from the battery to a speaker and an oscillator by a transistor. One of the supply lines is connected to one terminal of the battery via a diode, and further connected to the base of the transistor via a diode.

[0011]

According to the siren drive circuit of the present invention, when the potential of the power supply line connected to the base of the transistor via the diode is raised, the transistor is turned on, and the speaker and the oscillator are supplied with current from the battery, and the speaker is turned on. Sounds.

When the potential of the power supply line connected to the base of the transistor via the diode is lowered, the transistor is turned off, the current of the speaker and the oscillator is stopped, and the power supply line is connected to the battery via the diode. The battery is charged by drawing the charging current.

As described above, the battery can be charged and the sound of the siren drive circuit can be controlled by the two wires.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A driving circuit for a siren, which is an embodiment of the present invention, will be described with reference to the drawings. FIG. 1 shows a driving circuit of a siren according to an embodiment of the present invention. As shown in the figure, + B
The terminal is connected to the + terminal of the battery 8 via a series circuit of the diode 10 and the resistor 9 and the diode 11;
The ringing control terminal is connected to the
Connected to terminal.

One terminal of the speaker 4 is connected to the + B terminal, and the other terminal is connected to the negative terminal of the battery 8 via the transistor 3 and the transistor 2.

The + power supply terminal of the oscillator 1 is connected to the + B terminal, and the − power supply terminal is connected to the − terminal of the battery 8 via the transistor 2. The output signal terminal of the oscillator 1 is connected to the base of the transistor 3.

The + B terminal and the emitter of the transistor 2 are connected via a series circuit of a resistor 7, a resistor 6 and a resistor 5, and a connection point between the resistor 7 and the resistor 6 sounds via a diode 13. It is connected to the control terminal, and the connection point between the resistor 6 and the resistor 5 is connected to the base of the transistor 2.

In the above configuration, the + B terminal is connected to the + terminal of the car battery, and the sound control terminal is connected to the siren control terminal of the car security system.

When the siren control terminal goes to the GND level, the battery 8 is charged through the series circuit of the diode 10 and the resistor 9 and the diode 12.

At this time, a current flows from the connection point between the resistor 7 and the resistor 6 to the siren control terminal through the diode 13 and the potential at the connection point becomes low. Therefore, no current is supplied to the base of the transistor 2, the transistor 2 is turned off, and the speaker 4 does not sound.

When the siren control terminal is cut off from the GND terminal, the potential at the connection point between the resistor 7 and the resistor 6 increases,
A current is supplied to the base of the transistor 2, and the transistor 2 is turned on. Therefore, power is supplied to the oscillator 1, the output of the oscillator 1 is amplified by the transistor 3, and the speaker 4 is sounded.

As described above, the charging and the sound control of the battery are performed by the two wires. Also, if the wiring is cut in order to remove the siren, the speaker will beep, so that it will work very effectively as a car theft prevention device.

[0023]

According to the siren drive circuit of the present invention, the battery charging and ringing control are performed by two wires, and the number of wires is reduced as compared with the conventional one, so that the cost of the body harness is reduced and the wiring man-hour is reduced. Reduction is achieved. Further, since the number of wirings is small, the failure rate of the wiring system is also reduced.

Furthermore, since the speaker sounds when the wiring is cut in order to remove the siren, it works very effectively as a vehicle anti-theft device.

[Brief description of the drawings]

FIG. 1 is a wiring diagram showing a driving circuit of a siren according to an embodiment of the present invention.

FIG. 2 is a wiring diagram showing an example of a conventional siren drive circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Oscillator 2 Transistor 3 Transistor 4 Speaker 5 Resistor 6 Resistor 7 Resistor 8 Battery 9 Resistor 10 Diode 11 Diode 12 Diode 13 Diode

Claims (1)

(57) [Scope of request for utility model registration] 1. A siren drive circuit for charging a battery by a power supply line and turning on / off a current supplied from the battery to a speaker and an oscillator by a transistor, wherein one of the power supply lines is connected to one of the batteries via a diode. And a siren driving circuit connected to the base of the transistor via a diode.