JP2899706B2 - Vibration sensor for seismic sensor and gas meter using the sensor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION (a) Technical Field to which the Invention pertains This invention relates to a vibration sensor for a seismic device configured as a seismic device for detecting a seismic wave and directly detecting vibration, and a gas meter using the sensor.

(B) Conventional technology Japan is an earthquake country, and many felt and insensitive earthquakes occur every day.

Disasters caused by these earthquakes include primary disasters caused by the earthquake itself, and secondary disasters that accompany the earthquake.
Among them, secondary disasters are mostly man-made, and in the case of city gas in particular, necessary processing such as accurately determining earthquakes in real time and immediately shutting off gas supply when a dangerous state is predicted. By doing so, it is possible to prevent a considerable portion of disaster.

For this purpose, there is a vibration sensor for a seismic sensor shown in FIG. 4 for detecting a seismic wave.

In this vibration sensor, one end of a vibrator 3 is fixed to an upper surface of one side of a substrate 1 via a spacer 2, and a weight 4 is fixed to the upper surface of the other end of the vibrator 3. The vibrator 3 is formed so as to be vibrable, and the strain resistance element 5 is fixed to the fixed side base of the vibrator 3, and the vibration of the vibrator 3 is detected by the strain resistance element 5.

(C) Problems to be Solved by the Invention However, seismic waves have complicated waveforms and vibration directions vary widely, and in order to detect seismic waves, it is necessary to detect vibrations in all directions. .

Therefore, in the above-described configuration of the vibration sensor, since the detection direction is one direction in the surface thickness direction, it is necessary to detect at least three directions of the XYZ axes. However, as a result, the seismic device has a problem that the shape of the device becomes large and the device becomes expensive.

Therefore, an object of the present invention is to provide a vibration sensor for seismic detection capable of detecting vibrations in all directions with one vibrator and a gas meter using the sensor.

(D) Means for Solving the Problems The present invention relates to a vibration for a seismic sensor in which a vibration detecting element detects the vibration of a plate-shaped vibrator which is mounted in a cantilever manner on the upper surface of a substrate and has a weight portion formed on a free end side. In the sensor, the vibrator is formed with a thin portion that allows the weight portion side of the vibrator to vibrate in the plate thickness direction and a thin portion that allows the vibrator to vibrate in the plate surface direction. It is a vibration sensor for a seismic sensor corresponding to the vibration in the direction.

Furthermore, the present invention includes a shutoff valve disposed in a gas supply passage and a seismic sensor for detecting an earthquake, and operates the shutoff valve when the seismic sensor determines a dangerous earthquake to supply gas. A gas meter for blocking a passage, wherein the seismic sensor is a gas meter formed by the vibration sensor for a seismic sensor according to claim 1.

(E) Function In the vibration sensor for a seismic sensor according to the present invention and the gas meter using the sensor, the weight portion of the vibrator forms a thin portion that can vibrate in the plate thickness direction and the plate surface direction. The vibrator can vibrate in all directions of vibration, and the vibration detecting element can detect vibration in the XYZ axis directions.

(F) Effects of the Invention As described above, according to the present invention, it is not necessary to arrange a plurality of transducers three-dimensionally, so that the thickness of the device can be reduced, and the XYZ axes can be formed by one transducer. Since the vibrations in the directions and the combined directions thereof, that is, the vibrations in all the directions can be detected, the seismic sensor can be made compact, lightweight, and inexpensive.

Furthermore, when the above-described vibration sensor for a seismic sensor is used as a seismic sensor for a gas meter, the sensor is configured to be small, light, and inexpensive as described above. it can.

(G) Embodiment of the Invention One embodiment of the present invention will be described below in detail with reference to the drawings.

The drawing shows a vibration sensor for a seismic sensor, and in FIG.
A plate-shaped vibrator 12 is mounted on one upper surface of a plate-shaped substrate 10 via a spacer 11, and a weight 13 is fixed to the upper surface of the vibrator 12 on the loose fitting side, and the vibrator 12 vibrates. It is formed to be easy.

By forming a groove 14 in the width direction at the center of the back surface side of the above-described vibrator 12 and forming a thin portion 15 on the upper surface side, the weight 13 side is formed so that it can vibrate in the plate thickness direction, and further, a spacer A cut 16 is formed in the width direction from one side in the vicinity of 11, and a thin portion 17 is formed on the other side, so that it can be vibrated in the plate surface direction. And the thin portion 17 enables vibration in the XY axis direction.

Then, strain resistance elements 18, 18, 19 are fixed to the thin portions 15, 17, and when these vibration resistance elements 18, 18, 19 generate vibration, an analog signal reflecting the waveform of the vibration wave is generated. Output,
The strain resistance elements 18, 18 detect vibration in the Z-axis direction, and the strain resistance element 19 detects vibration in the XY-axis direction.

Therefore, when an earthquake occurs, the vibrator 12 can vibrate in all directions in the XYZ axis directions, and these vibrations are detected by the strain resistance elements 18, 18, 19.

FIG. 2 shows a control circuit block diagram of a seismic sensor formed using the vibration sensor 20 configured as described above. The power supply circuit 21 uses a battery power supply, and includes the strain resistance elements 18 and 19 and signal processing. Power is supplied to the unit 22.

The signal processing unit 22 measures and analyzes the signals from the distortion resistance elements 18 and 19 in the preceding stage, such as amplitude and frequency spectrum,
It is determined whether or not it is an earthquake, and when it is determined that the danger is predicted, the actuator, for example, the shutoff valve 23 is driven to close.

FIG. 3 shows an example in which the seismic sensor 24 constructed as described above is attached to a gas meter 25 for city gas. The shut-off valve 23 is located at the inlet port 26, and When it has determined a dangerous earthquake, it operates this shutoff valve 23,
Shut off the passage and stop gas supply.

According to the vibration sensor 20 for the seismic sensor shown in this embodiment, the thickness of the vibration sensor 20 can be reduced.
The XYZ axis directions and their combined directions by the transducers 12,
In other words, vibrations in all directions can be detected.
24 can be formed small, lightweight and inexpensive.

Further, when the vibrator 12 is formed of a semiconductor such as silicon, a large cost reduction can be achieved by mass production, and a power supply circuit and a signal processing unit can be integrated on the same substrate. It is possible to reduce the size and increase the reliability.

In the correspondence between the configuration of the present invention and the above-described embodiment, the weight portion of the present invention corresponds to the weight 13 of the embodiment, and similarly, the vibration detecting element corresponds to the strain resistance elements 18 and 19. However, the present invention is not limited only to the configuration of the above-described embodiment.

For example, the vibration detecting element is the strain resistance element 18, 19 of the embodiment.
Alternatively, it may be constituted by a piezoelectric element, a capacitance sensor, or the like.

[Brief description of the drawings]

 BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment of the present invention. FIG. 1 is a perspective view of a vibration sensor for a seismic sensor, FIG. 2 is a block diagram of a control circuit of the seismic sensor, FIG. FIG. 4 is a perspective view of a conventional vibration sensor. 10 ... substrate, 12 ... vibrator 13 ... weight, 14 ... groove 16 ... cut, 15, 17 ... thin section 18, 19 ... strain resistance element, 20 ... vibration sensor 24 ... feeling Tremor

Claims (2)

(57) [Claims] 1. A vibration sensor for a seismic sensor wherein a vibration detecting element detects the vibration of a flat vibrator having a cantilever mounted on the upper surface of a substrate and having a weight portion formed on a free end side, the vibration sensor comprising: The vibrator is formed with a thin part that allows the weight side of the vibrator to vibrate in the plate thickness direction and a thin part that allows the vibrator to vibrate in the plate surface direction. Dexterous vibration sensor. 2. A gas supply passage provided with a shut-off valve in a gas supply passage and detecting an earthquake, wherein the seismic sensor operates the shut-off valve when a dangerous earthquake is determined. A gas meter, wherein the vibration sensor is formed by the vibration sensor for a vibration sensor according to claim 1.