JPS59117696A - Crime preventor for vehicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical field] This invention relates to a military security device.

[Background technology]

In recent years, the number of thefts of cars themselves and thefts of various electrical components has been increasing, but no effective crime prevention device has been developed yet. This is because conventional devices are mainly mechanical, and no device has yet been developed that can warn of a criminal's intrusion (for example, the act of putting one's hand through a window). However, a car security system that used ultrasonic waves was previously developed, but it often malfunctioned, probably due to the effects of external vibrations and temperature.

[Purpose of the invention]

An object of the present invention is to provide a military security device that can issue an alarm to an intruder from the outside without causing malfunctions due to disturbance factors such as external vibrations, temperature, and humidity. : [Disclosure of the invention] The military security device of the first invention oscillates at the same wave number according to the capacitance between the sensor electrode installed in the vehicle body and electrically insulated from the vehicle body. The vehicle is characterized by detecting changes in the oscillation frequency of the oscillator, thereby detecting the intrusion of a human body into the vehicle body and issuing an alarm.

The vehicle security device of the second invention divides the output voltage of the oscillation circuit by the capacitance between the sensor electrode and the vehicle body and the voltage divider as in the first invention, and divides the output voltage of the oscillation circuit between the sensor electrode and the vehicle body. The system is characterized in that an intrusion of a human body into the vehicle body is detected by detecting a change in the divided voltage due to a change in capacitance between the two and an alarm is issued.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a block diagram of a military security device according to a first embodiment of the present invention. In FIG. 1, 1 is a metal car body, 2 is a sensor electrode installed inside the car body 1 in a state that is electrically insulated from the car body 1, and 3 is a sensor electrode 2 and the car body 1.
An oscillation circuit that oscillates at a frequency determined by the capacitance between the
4 is an FM detection circuit that performs FM detection on the oscillation output of the oscillation circuit 3 and generates a DC voltage that is different from the oscillation frequency;
6 is a comparator circuit that compares the output voltage of the FM detection circuit 4 with a reference voltage, and 6 is an alarm circuit that operates based on the output of the comparator circuit.

This military security device detects when a human body 7 enters the vehicle body.
The electric field inside the car body 1 changes, the capacitance between the car body 1 and the sensor electrode 2 changes, and as a result, the oscillation wave number of the oscillation circuit 3 changes, and the output voltage of the FM detection circuit 4 changes, The comparator circuit 5° detects this and activates the alarm circuit 6.

In this way, in this embodiment, a change in the capacitance between the sensor electrodes 2 between the vehicle body 1 and the vehicle body 1 due to the intrusion of the human body 7 into the vehicle body 1 is detected as a change in the oscillation frequency, and an alarm is issued. The capacitance between the vehicle body 1 and the sensor electrode 2 is not affected by sound or vibration from outside the vehicle body 1, nor is it affected by temperature or humidity, so that the capacitance between the vehicle body 1 and the sensor electrode 2 is not affected by the intrusion of the human body 7 into the vehicle body 1. can be detected and alarmed without contact without being affected by the above-mentioned disturbances, and theft etc. can be prevented.

FIG. 2 shows a block diagram of a military security device according to a second embodiment of the present invention. In FIG. 2, 8 is an excitation electrode installed inside the vehicle body 1 in a state where it is electrically insulated from the vehicle body 1 and the sensor electrode 2, and 9 is a high-frequency voltage of a constant frequency between the excitation electrode 8 and the vehicle body 1. This is an oscillation circuit that generates an electric field within the vehicle body 1 by adding 10 is the output voltage of the oscillation circuit 9, that is, the voltage applied to the capacitance between the excitation electrode 8 and the vehicle body 1, and the capacitance between the excitation electrode 8 and the sensor electrode 2, and the capacitance between the sensor electrode 2 and the sensor electrode 2. This is an amplifier circuit that amplifies the divided voltage of the capacitance between the senna electrode 2 and the vehicle body 1 when divided by the capacitance between the vehicle body 1. 11 is a detection circuit that detects the output of this amplifier circuit, and 12 is a detection circuit that integrates the output of the detection circuit 11 to detect the senna electrode 2 and the vehicle body 1.
This is an integrating circuit that converts the voltage into a DC voltage based on the capacitance between the two.

13 is a resistance. The comparator circuit 5 is similar to that of FIG. 1, and compares the output voltage of the integrating circuit 12 with a reference voltage. The rest of the configuration is the same as that in FIG. 1.

In this vehicle security device, when a human body 7 enters the vehicle body 1, the capacitance between the vehicle body 1 and the sensor electrode 2 changes, and the divided voltage between them changes. The output voltage of the integrating circuit 12 changes, which is detected by the comparator circuit 5 and activates the alarm circuit 6.

As described above, in this embodiment, a change in the capacitance between the sensor electrodes 2 between the vehicle body 1 and the vehicle body 1 due to the intrusion of the human body 7 into the vehicle body 1 is detected as a change in the partial voltage, and an alarm is issued. Therefore, the same effects as in the first embodiment can be obtained. Note that a partial voltage between the excitation electrode 8 and the sensor electrode 2 may be detected.

FIG. 3 shows a block diagram of a vehicle security device according to a third embodiment of the present invention. In FIG. 3, 14 is a coupling capacitor length (coupling element) used in place of the excitation electrode 8;
The voltage output from the oscillation circuit 9 is divided by a coupling capacitor 14 and added to the capacitance between the sensor electrode 2 and the vehicle body 1. Other configurations and operations are similar to those in FIG. 2.

The effects of this embodiment are similar to those of the first embodiment.

〔Effect of the invention〕

According to the military security device of the present invention, it is possible to issue an alarm to an intruder from the outside without causing malfunction due to external noise, vibration, temperature, humidity, or other disturbance factors.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a first embodiment of the invention, FIG. 2 is a block diagram of a second embodiment of the invention, and FIG. 3 is a block diagram of a third embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Vehicle body, 2... Sensor electrode, 3... Oscillation circuit, 4... FM detection circuit, 5... Controller circuit, 6... Alarm circuit, 7... Human body , 8... Excitation electrode, 9... Oscillation circuit, 10... Amplification circuit, 11...
Detection circuit, 12... Integrating circuit, 14... Coupling capacitor r ゛! .

Claims (4)

[Claims] (1) A sensor electrode installed in a vehicle body in a state where it is electrically insulated from the vehicle body; an oscillation circuit that oscillates at 8 wave numbers according to the capacitance between the sensor electrode and the vehicle body; A frequency change detection section that detects a change in the oscillation frequency of the circuit, a comparison circuit that generates an output when the frequency change detected by the frequency change detection section exceeds a predetermined value, and a comparison circuit that responds to the output of this comparison circuit. A car security device equipped with an alarm circuit. (2) A sensor electrode installed in the vehicle body in a state where it is electrically insulated from the bundle, an oscillation circuit that oscillates at a constant number of revolutions, and an output voltage of this oscillation circuit that is connected to the sensor electrode 8 and the A voltage divider that divides by the capacitance between the vehicle bodies, and a voltage change detection that detects a change in the divided voltage of either one of the sensor electrode and the capacitance between the vehicle bodies and the voltage divider. a comparator circuit that generates an output when the voltage change detected by the voltage change detection section exceeds a predetermined value;
A car security device includes an alarm circuit that responds to the output of this comparison circuit. (3) Claim (2), wherein the voltage divider is an excitation electrode installed in the vehicle body in a state electrically insulated from the vehicle body and the sensor electrode, and connected to the oscillation circuit. The car security device listed. (4) The vehicle security device according to claim (2), wherein the voltage divider is a capacitor connected between the oscillation circuit and the sensor electrode.