JP2003242567A - Anti-theft apparatus for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect a theft without providing an additional special apparatus in a vehicle in which an engine is started by operating an ignition key 2. <P>SOLUTION: The anti-theft apparatus according to this invention comprises a +B voltage detector circuit 5 for detecting a change in an output voltage of a battery 1 as the engine starts, an ACC power supply on/off detector circuit 4 for detecting an on/off state of the ACC power supply, and a control circuit 6. The control circuit 6 generates alarm of a large volume from a speaker 11 when the off state of the ACC power supply is detected after the change of the output voltage of the battery 1 has been detected. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing a vehicle such as an automobile from being stolen.

[0002]

2. Description of the Related Art Conventionally, as a vehicle anti-theft device,
For example, when the door is locked by the remote control key and the door is unlocked by a means other than the remote control key, it is determined that the door is stolen and a warning sound is generated. Has been adopted.

[0003]

However, each of the conventional anti-theft devices needs to be additionally equipped with a special device for detecting the occurrence of theft, which causes a problem that the structure becomes complicated. Therefore, an object of the present invention is to provide an antitheft device capable of detecting the occurrence of theft without additionally equipping a special device.

[0004]

SUMMARY OF THE INVENTION A vehicle antitheft device according to the present invention comprises a first detecting means for detecting a change in output voltage of a battery (1) due to engine start, and a power supply for accessory equipment including an audio equipment. The second detection means for detecting the on / off state of the supply and the battery by the first detection means
When the output voltage fluctuation of (1) is detected, and after the fluctuation ends, when the second detection means detects the off state of the power supply to the accessory device, a warning means for generating a loud alarm sound It is equipped with

In the vehicle equipped with the anti-theft device of the present invention, when the ignition key (2) is operated to start the engine, first, the ignition key (2) is operated to the accessory power-on position.
The supply of the power of the battery (1) to the accessory device including the audio device is started, and the voltage of the power rises to a predetermined value (for example, 12V). Furthermore, by operating the ignition key (2) to the engine start position,
Electric power of the battery (1) is supplied to the starter motor (14). As a result, the crankshaft of the engine is rotationally driven by the starter motor (14) to start the engine.

In a state where the crankshaft of the engine is rotationally driven by the starter motor (14), the load (1) of the battery (1) that supplies electric power to the starter motor (14) due to load fluctuations accompanying the rotational driving of the crankshaft. The output voltage fluctuates, and the fluctuation is detected by the first detection means. When the engine is started, the output voltage of the battery (1) is maintained at a substantially constant value (for example, 12V). Further, the voltage of the electric power supplied to the accessory device is maintained at a predetermined value (for example, 12V).

On the other hand, the battery (1) is connected to the starter motor (14) without operating the ignition key (2).
Or directly connect to the starter relay or solenoid connected to the starter motor, rotate the starter motor (14),
Even when the engine is started, the output voltage of the battery (1) varies with the rotation of the starter motor (14), and the variation of the output voltage is detected by the first detecting means. However, since the ignition key (2) has not been operated,
Even after the fluctuation of the output voltage of the battery (1) is completed, the accessory device is not supplied with power, and the second detection means detects the off state of the power supply. As a result, the warning means generates a loud alarm sound to notify the surroundings of the occurrence of theft.

In the warning means, an audio device equipped as an accessory device can be used to generate a warning sound, and when the occurrence of theft is detected, the audio device is provided with a battery (1). By supplying the electric power of the above, a loud alarm sound is generated from the audio device.

In a specific configuration, further, an input means for inputting a predetermined personal identification number, a judging means for determining whether the input personal identification number matches a pre-registered personal identification number, and a personal identification number And a warning stopping means for stopping the generation of the warning sound when the above conditions are met. According to the specific configuration, the alarm can be stopped by inputting the personal identification number recognized only by the owner of the vehicle.

[0010]

In the vehicle theft prevention device according to the present invention, the means for detecting the output voltage of the battery and the means for detecting ON / OFF of the power supply to the accessory device including the audio device are different from those of the conventional accessory device. Also, the warning sound can be generated by using an audio device, a speaker, or the like equipped in a conventional vehicle. Therefore, a function of detecting the change in the output voltage of the battery and determining the occurrence of the theft when the power supply to the accessory device is detected to be in the off state, for example, a function of controlling the operation of the accessory device is performed. The antitheft device of the present invention can be realized simply by adding it to the software of the computer. As described above, according to the present invention, it is possible to detect the occurrence of theft without additionally equipping a special device.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment in which the present invention is applied to an antitheft device for an automobile will be specifically described with reference to the drawings. FIG. 1 shows a main configuration of a vehicle embodying the present invention. An ignition key (2) to be operated when starting an engine is an OFF position of power off, an accessory.
(ACC) ACC position for turning on the power, IG position for turning on the ignition (IG) power, and START position for turning on the starter motor can be rotated to four positions. Therefore, by turning from the OFF position to the ACC position, the ACC power source is first turned on, turning from the ACC position to the IG position, and further turning from the IG position to the START position, the starter motor is started and the engine is started. After that, the ignition key (2) starts with the force of the spring.
Returning from the position to the IG position, the ACC power supply remains on.

As shown in FIG. 1, the battery (1) is connected to a solenoid (13) through an ignition key (2) and a starter relay (12), and the ignition key (2) is set to the START position as described above. By operating up to, the solenoid (13) is turned on, which activates the starter motor (14).

Further, the battery (1) is connected to a car audio device (3) as an ACC device, and the ACC power supply is turned on by operating the ignition key (2) as described above, so that the car audio device ( Required power is supplied to 3). Car audio system (3) is ACC
ACC power ON / O to detect power ON / OFF
The FF detection circuit (4), the + B voltage detection circuit (5) for detecting the output voltage (+ B voltage) of the battery (1), the control circuit (6) including a microcomputer, the numeric keypad, etc. An operation section (7) provided with, an audio section (8) provided with a CD player, a radio receiver, etc., and an audio section (8)
Electronic volume (9) for adjusting the output level of
The audio signal output from the audio section (8) comprises a power amplifier (10) that amplifies according to the adjustment amount of the electronic volume (9), and the audio signal output from the power amplifier (10) is a speaker. It is supplied to (11) and output as sound.

FIG. 2 shows ON / O of + B power supply, ACC power supply and IG power supply according to the position of the ignition key (2).
The switching state of FF is shown. Also, FIG. 3 (a) shows
ACC generated by operating the ignition key (2)
The change in voltage and the change in + B voltage are shown. As shown in the figure, by operating the ignition key (2) to the ACC position, the ACC voltage rises from 0V to 12V,
Then press the ignition key (2) from the IG position to START
By manipulating to the position, the ACC voltage drops to near 0V. When the starter motor (14) is started by operating the ignition key (2), the + B voltage temporarily drops due to the generation of load. Then, when the crankshaft of the engine is rotationally driven, the + B voltage gradually rises while fluctuating as shown by the load fluctuation at that time. When the engine starts, the ignition key (2) is I
Although it is returned to the G position, the ACC voltage returns to 12V as the engine starts as shown in FIG. 3A, and the + B voltage is maintained at approximately 12V after the above-mentioned fluctuation is subsided.

On the other hand, without operating the ignition key (2), the power supply line from the battery (1) is directly connected to the starter relay (12), the solenoid (13) or the starter motor (14) to start the starter. When the motor (14) is rotated and the engine is started, the + B voltage fluctuates and gradually rises as in the operation of the ignition key (2) as shown in FIG. 3 (b). On the other hand, the ACC voltage remains 0V as shown because the ignition key (2) is not operated.

Therefore, according to the present invention, as shown in FIGS.
Is the ACC voltage after + B voltage fluctuation is 0V as shown in 12
Whether or not the ignition key (2) is operated when the engine is started, that is, whether or not theft has occurred is determined depending on whether or not it is V.

FIG. 4 shows a procedure executed by the control circuit (6) of the car audio device (3) to determine whether or not a theft has occurred and to issue an alarm when the theft has occurred. First, in step S1, the ACC power ON / OFF detection circuit (4) determines whether or not the ACC power is ON. If the answer is YES, it means that the ignition key (2) has been operated. As a result, the process shifts to the normal reproduction mode of step S2, and the normal reproduction operation of the audio unit (8) according to the operation of the operation unit (7) and the electronic volume control (9) is executed.

On the other hand, if it is determined NO in step S1, the process proceeds to step S3, and the + B voltage detection circuit (5)
It is determined whether the + B voltage fluctuates or not. Here, when it is determined that the + B voltage has changed, it is determined in step S4 whether the + B voltage is changing. The fluctuation of the + B voltage can be easily detected by setting a threshold value in the range of 0 V to 12 V (for example, 6 V) and determining whether or not the + B voltage has passed the threshold value one or more times.

While the starter motor (14) is rotating, the determination in step S4 is repeated, and when the rotation of the starter motor (14) is stopped by starting the engine, step S4 is performed.
Is determined to be no, and the process proceeds to step S5. In step S5, the ACC power ON / OFF detection circuit (4) determines whether the ACC power is off. When the engine is started by the operation of the ignition key (2), the ACC power source is turned on as described above, so it is determined as NO in step S5, and the process proceeds to step S2. As a result, the operation unit (7) and the electronic volume (9)
The normal reproduction operation of the audio section (8) is executed according to the operation of.

On the other hand, when the engine is started without using the ignition key (2), AC is applied as described above.
Since the C power is still off, the determination in step S5 is YES, and the process proceeds to step S6. Step S6
Then, it is determined that the engine is started without using the ignition key (2), and then in step S7, the operation unit
The key operation of (7) is invalidated, and the personal identification number input mode is set. Then, in step S8, the electronic volume (9)
Is set to the maximum volume, and a predetermined warning sound is generated in step S9. The warning sound is generated, for example, by reproducing the warning sound previously recorded in a recording medium such as a CD or the memory of the control circuit (6) and outputting it from the speaker (11) through the power amplifier (10). You can When the owner of the automobile stops the generation of the warning sound, he / she operates the operation unit (7) to input the personal identification number.

Next, in step S10, it is determined whether or not a personal identification number has been input. If the determination is yes, the process proceeds to step S11, and the input personal identification number is registered in advance. Determine if it matches the number. Here, if the personal identification numbers do not match, the process returns to step S9 to continue the generation of the warning sound. When the personal identification numbers match, the process proceeds to step S12, the generation of the warning sound is stopped, and then the process returns to step S1.

According to the above procedure, the ignition key
When the engine is started without using (2) and there is a risk of theft, the electronic volume (9) will reach the maximum volume and a warning sound will be generated, so the situation will be notified to the surroundings,
Theft is prevented. Here, if the owner of the car inputs the personal identification number, the warning sound can be stopped. or,
According to the structure of the antitheft device shown in FIG. 1, the ACC power source O
Since the N / OFF detection circuit (4) and the + B voltage detection circuit (5) are also installed in the conventional car audio device, simply add the procedure of FIG. 4 to the software of the control circuit (6). It is possible to detect the occurrence of theft without equipping new equipment. In addition, the audio part (8) of the car audio device, the electronic volume
Since (9) and the power amplifier (10) are used, it is possible to inform the surroundings of the occurrence of theft without additionally equipping new equipment.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an anti-theft device according to the present invention.

FIG. 2 is a chart showing switching on / off of each power source according to the position of an ignition key.

FIG. 3 is a waveform diagram comparing changes in the power supply voltage when the ignition key is used to start the engine and when the ignition key is not used.

FIG. 4 is a flowchart showing a procedure of detecting the occurrence of theft and generating a warning sound.

[Explanation of symbols]

(1) Battery (2) Ignition key (3) Car audio equipment (4) ACC power ON / OFF detection circuit (5) + B voltage detection circuit (6) Control circuit (8) Audio section (9) Electronic volume (10) Power amplifier (11) Speaker (14) Starter motor

Continued front page    (72) Inventor Akira Imanaga             1-1-1, Sakata, Oizumi-cho, Ora-gun, Gunma Prefecture             FM MS Audio Sendy             Inside Lian Bahad (72) Inventor Takayuki Tanaka             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. F term (reference) 5C084 AA04 AA09 BB21 CC23 DD01                       DD02 EE06 FF03 GG03 HH01                       HH12

Claims (3)

[Claims] 1. An audio system comprising an ignition key (2) that can be operated to an engine start position via an accessory power-on position, the ignition key (2) being operated to an accessory power-on position. Supplying the battery (1) power to the starter motor (14) by starting the supply of the battery (1) power to the accessory device including the device and operating the ignition key (2) to the engine start position. A vehicle anti-theft device for detecting a change in output voltage of the battery (1) due to engine start, and a second detecting unit for detecting ON / OFF state of power supply to the accessory device; A change in the output voltage of the battery (1) is detected by the first detecting means, and after the change is finished, the second detecting means accesses the accessor. A vehicle theft prevention device, comprising: a warning means for generating a high-volume warning sound when an off state of power supply to the equipment is detected. 2. The input means for inputting a predetermined personal identification number, the judgment means for determining whether the input personal identification number matches a pre-registered personal identification number, and the personal identification number match. The vehicle anti-theft device according to claim 1, further comprising warning stopping means for stopping the generation of the warning sound. 3. The alarm device according to claim 1 or 2, wherein the warning means supplies a large amount of warning sound from the audio device by supplying electric power of a battery (1) to the audio device. Vehicle anti-theft device.