JPS61161477A - Sensor device for car - Google Patents

Abstract

PURPOSE:To use a glass crack sensor and a tire robbery sensor in common and to constitute a robbery alarm device for a car simply and inexpensively by forming an ultrasonic transmitting means, an ultrasonic receiving means, an ultrasonic reflecting means, etc. CONSTITUTION:An ultrasonic oscillator 1, an ultrasonic receiver 2, a fixed reflecting member 5, a movable reflecting member 6, etc. are arranged. An ultrasonic wave signal outputted from the oscillator 1 is distributed to right and left sides and reflected by respective reflecting members 5, 6, reflected by an window glass e.g. of the car, again reflected by the reflecting members 5, 6, and then received by the receiver 2. If the window glass is cracked during the stop of the car, the frequency of the ultrasonic wave is changed. Therefore, the glass crack state can be detected by detecting the change of the frequency or the like. On the other hand, when jack-up or the like is executed to remove a tire, the member 6 is simply oscillated around its shaft 4. Consequently, the Doppler phenomenon is generated in the signal inputted to the receiver 2 and the oscillation of the car can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sensor for a vehicle, and more particularly to a sensor device that uses an ultrasonic sensor to detect both glass breakage and tire theft.

(Prior Art) Conventionally, as an automobile theft alarm device, one that detects a glass breakage using an ultrasonic sensor is known. Also,
Regarding tire theft, there is a known system that uses a vibration sensor such as a piezoelectric element to detect a 71-tick when the tire is removed, determines that the tire has been stolen, and issues an alarm.

However, in such a conventional system, it is necessary to detect glass breakage and tire theft using separate devices, respectively, which makes the structure of the alarm device complicated and increases the price.

C) Problems to be Solved by the Invention) In view of the above-mentioned problems with the conventional type, the present invention makes it possible to share the glass breakage sensor and the tire theft sensor, simplifying the structure of the automobile theft alarm system and reducing the price. The purpose is to

Means for Solving Problem C) The vehicle sensor device according to the present invention includes an ultrasonic receiving means, an ultrasonic receiving means, and an ultrasonic wave inserted in a path from the ultrasonic transmitting means to the ultrasonic receiving means. Equipped with a sound wave reflecting plate or a hollow plate. The ultrasonic reflecting plate or shielding plate has a fixed part and a movable part that moves according to the operation of the vehicle.The fixed part mainly detects glass breakage, and the movable part detects tire theft. Detects vehicle tilt, sway, etc.

(Function) By using the above-mentioned means, when glass breakage occurs, the top 2 signal component is detected from the ultrasonic signal transmitted mainly through the fixed portion of the reflector or the root. An alarm is issued. Further, when the vehicle tilts or vibrates due to tire removal or the like, a Doppler signal component generated by the vibration or displacement of the movable portion of the reflector or shield plate is detected, and tire theft is detected.

(Example) Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 (&) and can) show the structure of a sensor portion of a vehicle sensor device according to an embodiment of the present invention. (same figure)
As shown in , the sensor device includes an ultrasonic oscillator 11, an ultrasonic receiver 2, and an ultrasonic reflector 3. The ultrasonic oscillator 1 and the ultrasonic receiver 2 are composed of, for example, a ceramic vibrator. The ultrasonic reflecting section 3 includes a triangular fixed reflecting member 5 fixed to the shaft 4 and a triangular movable reflecting member 6 that can be rotated around the shaft 4.

In the sensor device as described above, the ultrasonic signal output from the ultrasonic oscillator l is reflected by each of the reflecting members 5 and 6.
The light is distributed and reflected to the left and right, for example, by the window glass of an automobile, reflected again by each of the reflecting members 5 and 6, and received by the ultrasonic receiver 2. For example, if a window glass breaks while the car is stopped, it becomes possible to detect the cracked state of the ultrasonic receiver 22.

By the way, when the vehicle is stopped and a tire is removed, for example, or jumbled up, the above-mentioned movable reflective member 6 makes a simple vibration about the shaft 4, as shown by the dotted line in FIG. 1. Therefore, in this case, even if the glass is not broken, a drag phenomenon occurs in the ultrasonic signal input to the ultrasonic receiver 2, and it becomes possible to detect the vibration of the vehicle.

FIG. 2 shows a signal processing circuit connected to the device described above. The circuit in the figure includes an ultrasonic oscillation circuit 7, a mixing circuit 8, a low-pass filter 9, an amplifier 101M detector 31. Comparator 12, flip-flop] 3, and gate 14,
It is composed of a delay circuit 15, an alarm circuit 16, and the like. The ultrasonic oscillation circuit 7 is connected to the above-mentioned ultrasonic oscillator 1, and the above-mentioned ultrasonic receiver 2 is connected to the mixing circuit 8. Further, a system set signal for starting the system is applied to the terminal TI.

This system set signal is generated, for example, by a system set switch (not shown). Further, a door opening/closing signal indicating the opening/closing state VI4 of the door is inputted to the terminal 2.

Furthermore, an alarm prohibition signal generated by, for example, an alarm prohibition switch (not shown) is applied to the child T3.

In the circuit shown in FIG. 2, a signal from the ultrasonic oscillation circuit 7 is applied to the ultrasonic oscillator l, and an ultrasonic signal of a predetermined frequency is output. For example, this ultrasonic signal may be transmitted through a window glass, etc.
The received ultrasonic signal is reflected and input to the ultrasonic receiver 2 to generate a received ultrasonic signal and input to the mixing circuit 8. The mixing circuit 8 is
This received ultrasonic signal and the output signal of the ultrasonic oscillation circuit 7 are mixed to generate a signal having a frequency that is the difference between the two signals. Then, the signal components below a predetermined band are extracted by the low-pass filter 9 and the IIS! After being amplified by the detector circuit 11, the AM detection circuit 11 performs AM detection. A.M.
The detected signal is compared with the 'Jh quasi-voltage Vref in the comparator 12. If the Doppler effect occurs due to broken glass or vibration of a single unit as described above, the output of the detector 11 becomes higher than the reference voltage Vr@f and the output of the comparator 12 becomes high level. As a result, the flip-flop 13 is set and its output becomes high level. At this time, if the system set signal applied to the terminal TI is still at a level, and the door open/close signal applied to the terminal T2 remains at a high level for a while, that is, if the door open Mt is indicated, the output of the AND gate 14 is becomes high level, and the alarm circuit 16 generates an alarm sound, for example, by a buzzer. However, if the alarm prohibition signal is applied to the terminal T3, the flip-flop 13 is reset and the alarm circuit 16 is
Since the alarm is not activated, no alarm sound is output.

3-) and (bl) are a front view and a front view showing the specific structure of the sensor device shown in FIG. The seat #7 4 with attached is supported by a support plate 17, and the ultrasonic oscillator 1 and the ultrasonic receiver 2 are placed between these support plates 7 with anti-corrosion material 18 made of rubber or soft plastic material. Supported.

The sensor device 20 having the above-described structure is mounted on the ceiling 21 of an automobile, for example, as shown in FIG.

Although the above description has been made of the case where the Doppler effect of ultrasonic signals is used to detect glass breakage, tire theft, etc., the present invention is not limited to ultrasonic waves. - It is also possible to apply the present invention to cases where a similar detection is performed by using a shield plate and utilizing the fact that the detection signal of the original sensor changes due to, for example, a vehicle tilting trap.

C) Effects of the Invention As described above, according to the present invention, it is possible to detect glass, cracks, tire theft, etc. with a single sensor device with a simple structure, and a low-cost and highly reliable sensor is provided. A device is realized.

[Brief explanation of the drawing]

Fig. 1-) is a perspective view showing the structure of the seventh sensor part of a control device according to an actual example of the present invention;
FIG. 2 is a block circuit diagram showing the circuit configuration of the sensor device according to the 15A embodiment of the present invention, and FIG.
A front view and l showing the specific structure of the senna part in Figure (a).
11 side view, and FIG. 4 is an explanatory view showing the cause of the installation of the senna part shown in FIGS. 3 fa) and can).

Claims (1)

[Claims] An ultrasonic wave device having an ultrasonic transmitting means, an ultrasonic receiving means, a fixed part inserted into an ultrasonic propagation path from the ultrasonic transmitting means to the ultrasonic receiving means, and a movable part that moves according to the displacement of the vehicle. A sensor device for a vehicle, comprising a reflective means and capable of detecting at least glass breakage and tire theft.