JPH08240477A - Seismoscope - Google Patents

Abstract

PURPOSE: To provide a seismoscope which can perform a highly reliable earthquake sensing operation even in an inclined installation in any direction and at any angle by detecting change in magnetic flux distribution generated by rolling of a spherical magnet housed inside the cavity of a spherical surface cavity body to be freely rollable. CONSTITUTION: A spherical magnet 14 is housed inside a spherical surface-shaped cavity 12 of a spherical shell 13, and the axis is set so as to pass through almost the center of the cavity 12, and a bar-shaped coil winding member 15 is formed outside the spherical shell 13 integrally with this, and a conductor coil 16 is wound round the periphery of the member 15. Since the magnet 14 rolls on a spherical surface 11 by a quantity according to the magnitude of a seismic movement, the magnetic flux distribution by the magnet 14 inside and outside the spherical shell 13 changes, and density of a line of magnetic force penetrating the coil 16 also changes. Therefore, an electromagnetic induction current flows in the coil 16, and electromotive force is generated in an electromotive force detecting part 17. According to the electromotive force detecting result of the detecting part 17, a judging part 19 judges the propriety of output of an earthquake sensing signal 18 to show that an earthquake shock is felt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic sensor for detecting a vibration such as an earthquake, and more particularly to a seismic sensor which is built in a gas meter and outputs a seismic signal for shutting off gas.

[0002]

2. Description of the Related Art In recent years, many gas meters installed in consumers' houses such as city gas have a built-in seismoscope which detects a vibration such as an earthquake and outputs a gas cutoff signal. An example of such a seismic sensor is, for example, Shokai 61-48634.
Some are described in Japanese Patent Publication. In this seismic sensor, the lower surface of a vertically slidable disk is brought into contact with the upper surface of a sphere that is rotatably housed in a box having a concave conical inner bottom surface,
The plunger provided on the upper surface of the disk is brought into contact with the switch mechanism, and the disk mechanism moves upward due to the vibration of the ball, so that the switch mechanism operates. In this seismoscope, there is no protrusion in the center of the inner bottom surface of the concave cone, and the structure is such that the sphere is pushed back to the center by the weight of the disc itself, so the device itself is installed with some inclination (within the bottom slope). However, the return to the center of the sphere is good.

[0003]

As described above, in the conventional seismoscope, the bottom of the box for accommodating the sphere has a concave conical shape, and the vibration of the sphere mechanically actuates the switch mechanism. It was supposed to output a seismic signal. Therefore, in normal times (when there is no vibration), the sphere needs to be positioned at the center of the bottom surface of the box so as not to output a seismic signal. For this reason, it is necessary to mount the entire seismoscope with an inclination within the bottom slope, and the installation work still requires caution. In addition, even if the installation work is proper, if the seismic sensor inclines more than the bottom slope for some reason (such as impact), the ball will not return to the center of the bottom surface, It will no longer be used as a seismic device. In addition, even if the bottom slope is less than or equal to the bottom slope, the sphere may not return due to some cause (for example, friction between the sphere and the disc surface), which may be a false alarm for earthquake detection. This is the same when the bottom surface of the box is formed in another shape, for example, a curved surface such as a concave spherical surface.

Therefore, as a means for solving this problem, for example, a structure in which the entire seismoscope is suspended is adopted, and the seismoscope is made horizontal even if the attitude of mounting the seismoscope is slightly inclined. Can be considered. However, since some kind of support structure member is always required in the hanging structure, even if it is possible to support installation at a large inclination angle with respect to a certain specific direction, installation with a large inclination in another direction, In particular, there may be a case in which it cannot be installed in an extremely inclined position (for example, upside down). Further, since there are mechanical movable parts at two locations inside the seismic sensor and the suspension structure, the structure becomes complicated, and there are problems in downsizing of the device, reliability and price.

The present invention has been made in view of the above problems, and an object thereof is to make it possible to perform a highly reliable seismic motion even in a tilted installation in any direction and at any angle, and at the same time, it is extremely possible. An object is to provide a compact seismic sensor having a simple structure.

[0006]

According to a first aspect of the present invention, there is provided a seismoscope in which a spherical hollow body having a spherical cavity surrounded by a spherical surface is provided, and the spherical hollow body rolls inside the spherical cavity. It is provided with a spherical magnet housed freely and magnetic flux change detecting means for detecting a change in magnetic flux distribution caused by rolling of the spherical magnet. In this seismoscope, when a vibration such as an earthquake occurs, the spherical magnet housed inside the spherical cavity rolls to change the magnetic flux distribution. By detecting this, it is possible to make a shock. Since the inner wall of the spherical cavity is a spherical surface, the spherical magnet moves in the same way by the vibration even when the entire seismoscope is installed in any direction, and the seismic shock is possible in the mounting state in all directions.

According to a second aspect of the present invention, there is provided a seismic sensor according to the first aspect, wherein the magnetic flux change detecting means is wound around at least the outside of the spherical cavity to detect a change in magnetic flux penetrating itself. It is configured to include a conductive wire coil portion that generates a corresponding electromagnetic induction electromotive force, and an electromotive force detection unit that detects the electromagnetic induction electromotive force generated by the conductive wire coil portion. In this seismoscope, an electromagnetic induction current flows through the wire coil portion due to a change in the magnetic flux distribution caused by the rolling of the spherical magnet due to the vibration, and this is detected as an electromagnetic induction electromotive force.

According to a third aspect of the invention, in the second aspect, the conductor coil portion has at least an axis passing through substantially the center of the spherical cavity of the spherical cavity. A wound first coil, and a coil wound on the opposite side of the spherical hollow body sandwiching the spherical cavity so as to have the same axis as the first coil and in phase with the first coil. The second coil is connected to the second coil. In this seismic sensor, when the spherical magnet rolls in the axial direction of both coils, the change in the magnetic flux density penetrating both coils becomes larger than that in the case of only one coil, so the detected electromagnetic induction electromotive force also becomes large. , The seismic sensitivity in the axial direction of the coil becomes larger. On the other hand, when the spherical magnet rolls in the other axial direction, the direction of the change in the magnetic flux penetrating both coils is opposite to each other, and electromagnetic induction electromotive force in the opposite direction is generated in each coil, so that the two cancel each other. It Therefore, it has a sharp seismic sensitivity in the axial direction of the coil.

According to a fourth aspect of the present invention, there is provided a seismic sensor according to the second aspect, wherein the conductor coil portion is provided at least near a central portion of the spherical cavity body so as to surround the spherical cavity itself. It is configured to include a coil wound around the periphery. In this seismic sensor, the spherical magnet is always located very close to the conductor coil regardless of the installation direction. For this reason, the density of the magnetic flux penetrating the conductor coil greatly changes regardless of the position of the spherical magnet (that is, regardless of the installation direction of the seismic sensor), and the sensitivity becomes good. In particular,
The sensitivity of the conductor coil in the axial direction is large and it has directivity.

According to a fifth aspect of the present invention, there is provided the second aspect of the seismic response device according to the second aspect, further comprising outputting a seismic response signal indicating that an earthquake has been detected in accordance with the detection result of the electromotive force detecting means. The determination means for determining is provided. In this seismic sensor, based on the detected electromagnetic induction electromotive force, etc.,
It is determined whether to output a seismic signal.

According to a sixth aspect of the present invention, in the seismic detector according to the fifth aspect, the electromagnetic induction electromotive force detected by the electromotive force detecting means by the determining means exceeds a predetermined threshold value. It is configured to sometimes determine that the seismic signal is output. This seismic sensor outputs a seismic signal only when the electromagnetic induction electromotive force exceeds a predetermined threshold value, that is, when the seismic intensity is equal to or higher than a certain level.

According to a seventh aspect of the present invention, there is provided a seismic detector according to the fifth aspect, wherein the determination means causes the electromagnetic induction electromotive force detected by the electromotive force detection means to have a predetermined threshold value for a predetermined time. It is configured to determine that the seismic signal is to be output when the above-mentioned continuation is exceeded. This seismic sensor outputs a seismic signal only when the electromagnetically induced electromotive force continuously exceeds a predetermined threshold value for a certain time or more, that is, when the amplitude and period of the shaking are more than a certain value.

According to an eighth aspect of the present invention, there is provided the seismic detector according to the fifth aspect, wherein the determining means determines that the electromagnetic induction electromotive force detected by the electromotive force detecting means has a predetermined threshold within a predetermined time. The number of times exceeding the value is counted, and when the count value exceeds a certain value, it is configured to determine that the seismic signal is output. With this seismic sensor, only when the number of times the electromagnetic induction electromotive force exceeds a predetermined threshold value within a predetermined time exceeds a certain value, that is, when the shaking of a certain magnitude or more continues for a certain time or more. A seismic signal is output. Therefore, in the case of a tremor due to a mere temporary impact, the seismic signal is not output, and the malfunction is prevented.

According to a ninth aspect of the present invention, there is provided the seismic transducer according to the fifth aspect, wherein the conductive wire coil portions are wound so as to have at least axial directions orthogonal to each other, and generate electromagnetic induction electromotive force. The electromotive force detection unit includes a plurality of individually generated coils and is configured to individually detect each electromagnetic induction electromotive force generated by each coil. In this seismic sensor, each electromagnetic induction electromotive force generated in each of the plurality of coils is individually detected, and based on this, it is determined whether or not a seismic sensor signal should be output. Therefore, the seismic sensitivity is substantially equal in the axial direction of each coil.

According to a tenth aspect of the present invention, there is provided the nineteenth aspect of the present invention, wherein the determining means determines whether any one of the electromagnetic induction electromotive forces detected by the electromotive force detecting means for each coil. It is configured to determine that the seismic signal is to be output when a predetermined threshold value is exceeded. In addition to the action of the seismoscope according to claim 9, when the electromagnetic induction electromotive force exceeds a predetermined threshold value, that is, The seismic signal is output only when the seismic intensity is above a certain level.

According to an eleventh aspect of the present invention, there is provided the seismic absorber according to the ninth aspect, wherein the determination means is any one of the electromagnetic induction electromotive forces detected for each coil by the electromotive force detection means. It is configured to determine that the seismic signal is output when the predetermined threshold value is continuously exceeded for a certain period of time or longer. In addition to the function of the seismoscope according to claim 9, the seismoscope outputs a seismic signal only when the amplitude and the period of the shaking are equal to or more than a certain level, in addition to the function of the seismoscope according to claim 9. To be done.

According to a twelfth aspect of the present invention, in the seismic sensor according to the ninth aspect, the electromagnetic induction electromotive force detected by the electromotive force detecting means for each coil by the determining means is within a predetermined time. The number of times exceeding a predetermined threshold value is counted, and when any one of the count values exceeds a certain value, it is determined to output the seismic signal. In addition to the action of the seismoscope according to claim 9, the seismoscope further senses only when a vibration of a certain magnitude or more continues for a certain time or more, like the seismoscope according to claim 8. Since a seismic signal is output, malfunctions due to a simple temporary shock are prevented.

According to a thirteenth aspect of the present invention, in the seismic instrument according to the ninth aspect, the determining means and the determining means include:
A vector sum of electromagnetic induction electromotive forces detected for each coil by the electromotive force detection means is obtained, and when the vector sum exceeds a predetermined threshold value, it is determined to output the seismic signal. It is configured in. In this seismoscope, since the vibration components in each axial direction are combined and used as a determination target, in addition to the effect of the seismic shock absorber of claim 6 and the operation of claim 9, a direction other than the axial direction of each coil The magnitude of the quake is also correctly evaluated.

According to a fourteenth aspect of the present invention, in the seismic detector according to the ninth aspect, the determining means obtains a vector sum of electromagnetic induction electromotive forces detected for each coil by the electromotive force detecting means. It is configured to determine that the seismic signal is output when the vector sum continuously exceeds a predetermined threshold value for a certain period of time or longer. In addition to the action of the seismoscope according to claim 9, in this seismoscope, the magnitude of vibration of each coil in a direction other than the axial direction is correctly evaluated, and further, according to claim 7, Similar to a seismic instrument, a seismic signal is output only when the amplitude and period of shaking are above a certain level.

According to a fifteenth aspect of the present invention, in the seismic sensor according to the ninth aspect, the determining means obtains a vector sum of electromagnetic induction electromotive forces detected for each coil by the electromotive force detecting means. Along with this, the number of times that this vector sum exceeds a predetermined threshold value within a predetermined time is counted, and when the count value exceeds a certain value, it is configured to determine that the seismic signal is output. Is. In addition to the function of the seismoscope according to claim 9, the seismoscope is capable of correctly evaluating the magnitude of vibration of each coil in a direction other than the axial direction, and further, according to claim 8. As with the seismic device, malfunctions due to simple temporary shocks are prevented.

According to a sixteenth aspect of the present invention, in the seismic detector according to any one of the first to fifteenth aspects, the spherical hollow body is a spherical shell having a spherical outer peripheral surface.

According to a seventeenth aspect of the present invention, there is provided the seismic sensor according to any one of the first to sixteenth aspects, wherein a viscous fluid is sealed in the spherical cavity of the spherical hollow body. In this seismic sensor, in addition to the function of the seismic sensor described in the above claims, the movement of the spherical magnet is suppressed to some extent by the function of the viscous fluid as a damper, which contributes to the prevention of malfunction.

[0023]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a partial cross section of the essential part of a seismoscope according to an embodiment of the present invention. This shock absorber 10
A spherical shell 13 having a spherical cavity 12 formed by a spherical surface 11 therein, a spherical magnet 14 housed inside the spherical cavity 12 of the spherical shell 13, and an axis passing through substantially the center of the spherical cavity 12. A rod-shaped coil winding member 15 integrally formed with the spherical shell 13 in this manner, and a conductive wire coil 16 wound around (wound around) the coil winding member 15; An electromotive force detection unit 17 that detects the magnitude of an electromagnetic induction electromotive force (hereinafter referred to as an electromotive force) generated at both ends of the conductor coil 16 due to the rolling (moving by rolling) of the spherical magnet 14, and an electromotive force detection unit. A determination unit 19 for determining whether to output a seismic signal 18 indicating that an earthquake has been sensed according to the detection result of 17 is provided, and can be installed in an arbitrary posture by a mounting tool (not shown). The seismic sensor 10 is installed inside (or outside) a gas meter (not shown), and is controlled so that the gas cutoff valve of the gas meter is closed according to the seismic signal 18.

A gas such as air is usually enclosed in the spherical cavity 12, but a minute vent hole may be provided in the spherical shell 13 in consideration of expansion or contraction due to temperature change. It should be noted that a viscous fluid such as silicon oil may be enclosed in the spherical cavity 12 as a damper for suppressing rolling of the spherical magnet 14 and preventing malfunction.

The spherical shell 13 is a spherical hollow body having a spherical outer peripheral surface, but the outer shape is not limited to a spherical shape as long as it contains a spherical hollow, and for example, a rectangular parallelepiped, a cube, a cylinder, or an ellipse. It may be the body or the like. The spherical shell 13 is made of a non-magnetic material such as synthetic resin, and can be integrally formed with the coil winding member 15 by injection molding, for example. However, since it is necessary to house the spherical magnet 14 inside the spherical shell 13, in practice, the hemispherical shell integrally molded with the coil winding member 15 and another hemispherical shell molded separately from this are joined together. It is preferable to form the spherical shell 13.

In this embodiment, the coil winding member 15
Although it is formed integrally with the spherical shell 13, they may be formed separately. In this case, the coil winding member 15 may be made of a material other than synthetic resin, and for example, a dust core or the like having a large magnetic permeability and no current flowing (small eddy current loss) can be used.

The spherical magnet 14 is a spherical permanent magnet and forms a magnetic field around it by the magnetic flux lines (or magnetic force lines) as shown in FIG. In this figure, the S / N poles are shown to match the vertical direction of the spherical magnet 14, but in reality the S / N pole direction is undefined, and due to the rolling of the spherical magnet 14, The direction is changing.

The coil winding member 15 is made of a non-magnetic material as described above and is formed integrally with the spherical shell 13,
The shape is not limited to the cylindrical shape as shown in the figure, and may be a prismatic shape or the like. When the spherical hollow body is replaced by the spherical hollow body and the outer shape is a cylinder or the like, the coil winding member 15 is not particularly required, and for example, inside the material (thickness portion) at the time of molding, as shown in the drawing. Wire coil 16 in posture
May be contained.

The electromotive force detecting section 17 is provided with a resistor (not shown) for generating a voltage across the resistor according to the induced current generated in the conductor coil 16, and detects the voltage across the resistor as an electromotive force. It is like this.

Next, the operation of the seismoscope 10 having the above-mentioned configuration will be described with reference to FIG. Note that the vertical direction in FIG. 1 represents the vertical direction, and the seismoscope 10 is assumed to be attached in such a posture that the axis of the coil winding member 15 faces the horizontal direction.

In normal times (that is, when there is no vibration such as an earthquake), the spherical magnet 14 is placed at the lowest point on the spherical surface 11 of the spherical cavity 12, and the magnetic flux lines shown in the figure are generated. It penetrates the conductor coil 16. Here, when a vibration due to an earthquake or the like occurs, the spherical magnet 14 rolls back and forth, left and right on the spherical surface 11 by an amount according to the magnitude of the vibration, so that the magnetic flux distribution by the spherical magnet 14 inside and outside the spherical shell 13 is reduced. The density of the magnetic flux lines passing through the conductor coil 16 also changes. As a result, an electromagnetic induction current (hereinafter referred to as an induction current) flows through the conductor wire coil 16 in a direction in which a magnetic flux line that cancels the change in the magnetic flux density is generated. This induced current flows through a resistor (not shown) of the electromotive force detection unit 17 and generates an electromotive force V at both ends thereof. In this case, the electromotive force V changes in the +/- direction as the spherical magnet 14 rolls, as shown in FIG. 3, for example. This electromotive force V is input to the determination unit 19, and whether or not to output the seismic signal 18 is determined according to the value thereof.

Specifically, as shown in FIG.
9 samples the electromotive force V at regular intervals (step S101), and compares the absolute value of the sampled value (V) with a preset threshold value (V _TH ) (step S101).
102). When the absolute value of the sampling value (V) does not exceed the threshold value (V _TH ) (step S102;
Y), the next sampling is performed again, and the threshold value (V _TH )
If it exceeds (step S102; N), the level signal "1" is output as the seismic signal 18. It is assumed that the output level of the determination unit 19 in normal times is held at "0".

As described above, in this embodiment, the spherical cavity 1
While accommodating the spherical magnet 14 in the inside of 2 in a rollable manner,
The change of the magnetic flux distribution due to the spherical magnet 14
Since the detection is performed by the sensor 6, the spherical magnet 14 is installed regardless of the posture of the entire seismoscope 10 (for example, when the axis of the wire coil 16 faces the vertical direction as shown in FIG. 6). It is possible to detect the rolling motion of the, and it is possible to obtain the omnidirectional seismic performance.

The determination of whether the seismic signal 18 is output by the determination unit 19 may be performed as follows to prevent malfunction. That is, in FIG. 3, the time t at which the absolute value of the electromotive force exceeds the threshold value (V _TH ) is longer as the fluctuation is larger and the cycle is longer. Therefore, the absolute value of the electromotive force V is increased as in the above embodiment (FIG. 2). The value is not used to immediately judge whether or not the seismic signal 18 is output, but only when the time t during which the absolute value of the electromotive force V continuously exceeds the threshold value (V _TH ) becomes a certain time or more. The seismic signal 18 is output (that is, only when the amplitude and period of the shaking are above a certain level). As a result, it is possible to prevent the gas cutoff valve of the gas meter from operating due to the output of the seismic signal 18 due to a small earthquake or a small vibration caused by the passage of a vehicle. A seismic signal is output.

The determination operation of the determination unit 19 may be performed as follows in order to distinguish a true earthquake from other simple impacts. That is, for example, when a ball or the like collides with the seismic sensor 10, as shown in FIG. 4, the amplitude of the electromotive force is initially large, but the vibration does not continue,
It decays in a very short time. Therefore, the number of times that the absolute value of the electromotive force exceeds the threshold value (V _TH ) within a predetermined time (T ₀ ) is counted, and the seismic signal 18 is output only when the count value exceeds a certain value. To do so.

Specifically, as shown in FIG. 5, the setting unit 19
Detects the peak value (V _P ) of electromotive force by sampling at regular intervals (step S201). If the absolute value of the peak value (V _P) does not exceed the threshold value (V _TH) (step S201; N), it is performed again for the next peak value detection (step S201). On the other hand, if the threshold value (V _TH ) is exceeded (step S202; Y), "1" is set in a counter (not shown) and step S20 is performed.
3) Start a timer (not shown) (step S2
04), the next peak value is detected (step S20).
5).

[0038] Thus if the absolute value of the detected peak value (V _P) does not exceed the threshold value (V _TH) is (step S2
06; N), the next peak value is detected again (step S).
205). On the other hand, when the threshold value (V _TH ) is exceeded (step S206; Y), the counter is incremented by 1 (step S207). Then, until the timer times out (step S208; Y), step S
The processing from 205 to S207 is repeated.

When the timer times out (step S
108; Y), the determination unit 19 compares the count value at that time with a predetermined value (C _TH ). And the count value is C _TH
If it exceeds (step S209; Y), it is determined to be an earthquake and the level "1" is output as the seismic signal 18 (step S210). On the other hand, when the count value does not exceed C _TH (step S209; N), it is determined to be a simple impact and the output is held at "0" (step S21).
1). In this way, a malfunction can be prevented by distinguishing a vibration caused by a simple impact such as a ball collision from an earthquake.

FIG. 6 shows a state in which the seismic sensor 10 is installed with the axis of the conductor coil 16 oriented vertically. In this state, the spherical magnet 14 is located farthest from the wire coil 16, so that the wire coil 16 is originally
There is little magnetic flux penetrating the. Therefore, the spherical magnet 1 due to the earthquake
Even if 4 rolls to the position 14 'or 14''to change the magnetic flux density distribution, the density change of the magnetic flux penetrating the conductive wire coil 16 is extremely small and the electromotive force becomes minute, so that the sensitivity is extremely lowered. That is, the detection sensitivity varies depending on the mounting posture of the seismic sensor 10, and the seismic sensitivity becomes directional. Therefore, in order to eliminate such seismic sensitivity directionality, as shown in FIG. Then, a plurality of conductor coils are arranged.

FIG. 7 shows a partial cross section of the essential part of a seismoscope according to another embodiment of the present invention, which is intended to eliminate the above-mentioned directionality of seismic sensitivity. In this figure, the same components as those of the above-mentioned embodiment (FIG. 1) are designated by the same reference numerals and the description thereof will be omitted as appropriate.

The seismoscope 30 has a spherical shell 13 having a spherical cavity 12 formed by a spherical surface 11 therein, a spherical magnet 14 housed in the spherical cavity 12 of the spherical shell 13, and a spherical surface. The spherical shell 13 has axes in the directions of x, y, and z axes which pass through substantially the center of the hollow cavity 12 and are orthogonal to each other.
Rod-shaped coil winding members 15 _x , 15 _y and 15 _z integrally formed with the outside of the coil, and conductor coils wound around these coil winding members 15 _x , 15 _y and 15 _z , respectively. 16 _x , 16 _y, and 16 _z, and an electromotive force detection unit 17 _x that detects the magnitude of electromagnetic induction electromotive force generated at each end of the wire coils 16 _x , 16 _y, and 16 _{z due to} rolling of the spherical magnet 14. 17 _y and 17 _z
And a determination unit 39 that determines whether to output the seismic signal 18 based on the electromotive force signals V _x , V _y, and V _z output from the electromotive force detection units 17 _x , 17 _y, and 17 _z , respectively. It can be installed in any posture by a mounting tool (not shown).

FIG. 8 shows the configuration of the judging section 39 shown in FIG. This determination unit 39 includes electromotive force detection units 17 _x , 17
Determination circuit 3 to which electromotive force signals V _x , V _y and V _z output from _y and 17 _z (FIG. 7) are input
2 _x , 32 _y and 32 _z , and these decision circuits 3
The OR gate 33 outputs the seismic signal 18 by ORing the outputs of 2 _x , 32 _y and 32 _z . Other configurations are the same as those in FIG. Note that, in FIG. 7, the seismoscope 30 is installed so that the z axis coincides with the vertical direction, but the present invention is not limited to this, and the seismoscope 30 can be installed in any direction (posture).

The operation of the seismoscope 30 having the above configuration will be described. In normal times, the spherical magnet 14 is placed at the lowest point on the spherical surface 11 of the spherical cavity 12, and the magnetic flux lines pass through the respective wire coils 16 _x , 16 _y and 16 _z .
Here, when a vibration due to an earthquake or the like occurs, the spherical magnet 14 rolls back and forth, left and right, etc. on the spherical surface 11 by an amount according to the magnitude of the vibration, so that the magnetic flux distribution inside and outside the spherical shell 13 changes. The density of the magnetic flux lines passing through the conductor coils 16 _x , 16 _y and 16 _z also changes. Thereby, each conductor coil 1
Induced currents flow in 6 _x , 16 _y and 16 _z , and these are detected as electromotive forces V _x , V _y and V _z by electromotive force detection units 17 _x , 17 _y and 17 _z , respectively.
Also in this case, the electromotive forces V _x , V _y and V _z change in the +/− direction as the spherical magnet 14 rolls, as shown in FIG. The electromotive forces V _x , V _y and V _z are determined by the determination unit 39.
_Are input to the decision circuits 32 _x , 32 _y and 32 _z , respectively. For each decision circuit 32 _x , 32 _y and 32 _z ,
A determination operation similar to that shown in FIG. 2 is performed, and the level signal "1" (sensing) or "0" is output according to the determination result.
(Non-sensing) is output. Then, the decision circuits 32 _x , 3
When one of the judgment outputs of 2 _y and 32 _z is “1”, the level signal “1” is output from the OR gate 33 as the seismic signal 18.

In this way, in the present embodiment, any one of the electromotive forces V _x , V _y and V _z detected from the conductor coils 16 _x , 16 _y and 16 _{z is the} threshold value (V _TH ), The seismic signal 18 will be output. Therefore, the rolling of the spherical magnet 14 can be detected with the same sensitivity regardless of the posture of the entire seismoscope 30, and seismic performance without directionality can be obtained.

FIG. 9 shows another example of the configuration of the judging section shown in FIG. As shown in this figure, the determination unit 39 ', calculates the vector sum of the electromotive force detecting portion 17 _x, 17 _y, and 17 _z electromotive force signal V _x output respectively (FIG. 7), V _y and V _z And a determination circuit 35 for determining whether the seismic signal 18 should be output based on the vector sum calculated by the vector sum calculation unit 34.

The operation of this judging section 39 'is as follows. That is, the vector sum calculation unit 34 determines that the electromotive force signal V
_{Based on x} , V _y and V _z , the vector sum V _SUM is calculated by the following equation (1). V _SUM = (V _x ² + V _y ² + V _z ² ) ^1/2 (1)

The decision circuit 35 outputs a level signal "1" as the seismic signal 18 when the vector sum V _SUM exceeds a predetermined threshold value (V _TH ), and otherwise. Holds at level "0".

Therefore, in the case where the judgment section is constructed as shown in FIG. 9, the vibration components in the respective axial directions are combined to be a judgment target, so that vibrations in directions other than the (x, y, z) axes are However, the size is evaluated correctly and the reliability of seismic shock is improved.

FIG. 10 shows a partial cross section of a main part of a seismoscope according to another embodiment of the present invention. This shock absorber 50
In the seismoscope 10 of FIG. 1, another coil winding member 15 ′ having an axis in the same direction as the axis of the coil winding member 15 (this is referred to as the x axis) is wound with the spherical shell 13 in between. The conductor wire coil 16 ′ is disposed on the opposite side of the attaching member 15 and is wound around the coil winding member 15 ′ in the same winding direction as the conductor wire coil 16, and the one end 41 of the conductor wire coil 16 and the conductor wire coil 1 are arranged.
6'is connected in phase with one end 42. Other configurations are the same as in the case of FIG. 1, and the installation direction (posture) is not limited to the illustrated direction, and the device can be installed in any direction.

Next, the operation of the seismoscope 50 having the above-described structure will be described. In this seismic sensor 50, the conductor coil 16 and the conductor coil 16 'are connected in phase, so that, for example, when the spherical magnet 14 rolls in the x-axis direction, only one conductor coil 16 ( Compared with FIG. 1), the change in the magnetic flux density penetrating these conductor coils 16, 16 'becomes large, and the detected electromotive force also becomes large. That is, the seismic sensitivity in the x-axis direction becomes larger. On the other hand, considering the case where the spherical magnet 14 rolls in the y-axis or z-axis direction, the direction of the change in the magnetic flux penetrating the conductive wire coil 16 and the direction of the change in the magnetic flux penetrating the conductive wire coil 16 'are opposite. Therefore, electromotive force in the opposite direction is generated in each of the conductive wire coils 16 and 16 ', and the two are canceled. That is, the configuration of FIG. 10 has seismic sensitivity with higher directivity. Therefore, the seismoscope of the present embodiment is particularly effective in specifying the direction of vibration. In addition,
By arranging such in-phase connected pair coils with respect to the x, y, and z axes, sharp sensitivity can be obtained in each axial direction. Also in this case, the electromotive force obtained from the wire coil pair for each axis is determined by the determination unit having the configuration shown in FIG. 8 or 9, so that seismic performance with extremely high sensitivity is obtained in all directions. be able to.

FIG. 11 shows a partial cross section of the essential part of a seismoscope according to another embodiment of the present invention. This shock absorber 60
In the seismoscope 10 of FIG. 1, instead of the coil winding member 15 and the conductor coil 16, a conductor coil 43 is wound around the center of the spherical shell 13 so as to surround the spherical shell 13 itself as a spherical hollow body. It was done. The axis of the coil is the x direction. Other configurations are the same as in the case of FIG. 1, and the installation direction (posture) of the seismic sensor 50 is not limited to the illustrated direction, and the seismic sensor 50 can be installed in any direction.

In this seismic sensor 50, the spherical magnet 14 is always located extremely close to the conductor coil 43 regardless of the installation direction. Therefore, for example, considering the case where the spherical magnet 14 rolls in the x-axis direction, the magnetic flux density penetrating the conductor coil 43 does not depend on the position of the spherical magnet 14 (that is, in the installation direction of the seismic sensor 50). Big change) Further, when the spherical magnet 14 rolls in a direction other than the x-axis direction, the magnitude of the change in magnetic flux does not much depend on the installation direction, but the magnitude is generally larger than that in the case of rolling in the x-axis direction. It will be smaller. That is, also in this case, as in the example of FIG. 10, the sensitivity is high in the x-axis direction,
It has directivity. Therefore, in the same manner as the conductor coil 43, the conductor coil is used for the y-axis and the z-axis as well.
If it is wound around itself (not shown), sharp sensitivity can be obtained in each axial direction. Therefore, in this case as well, by determining the electromotive force obtained from the conductor coil of each axis by the determination unit having the configuration shown in FIG. 8 or 9, it is possible to eventually obtain a highly sensitive seismic performance in all directions. it can.

Although the seismoscope of each of the above embodiments is described as being used to output a seismic signal, which is an operating condition of a gas cutoff valve of a gas meter, for example, the present invention is not limited to this. Of course, it can be applied to other uses (for example, for stoves and fan heaters).

[0055]

As described above, according to the seismoscope of the present invention, the spherical magnet is rotatably housed in the spherical cavity surrounded by the spherical surface, and the spherical magnet rolls. Since the change in the magnetic flux distribution that occurs is detected, the spherical magnet will move in the same way due to the vibration even if the entire seismoscope is installed in any direction, and it is possible to perform seismic shock in the mounting state in all directions. For example, flip upside down and attach,
Even when installed in an extreme posture, it is possible to receive a shock. That is, there is an effect that it is possible to reduce the mounting direction dependency of the seismic sensitivity.

Particularly, according to the seismoscope according to claim 3 or claims 16 or 17, which cite it, the first coil and the second coil are arranged so that the axis passes through substantially the center of the spherical cavity. Since both and are wound with a spherical cavity in between, and both coils are connected in phase, the movement of the spherical magnet in the axial direction of the coil is always detected with sufficient sensitivity by either coil. The axial seismic sensitivity is higher. On the other hand, the movement of the spherical magnet in the other axial direction causes electromagnetic induction electromotive force in the opposite direction in each coil to cancel each other. Therefore, this seismic sensor has a sharp seismic sensitivity in the axial direction of the coil, and is particularly effective in specifying the direction of vibration.

Claim 4 or Claim 1 quoting this
According to the seismoscope of 6 or 17, since the conductive wire coil is wound around the central portion so as to surround the spherical cavity itself, the density of the magnetic flux penetrating the conductive wire coil accompanying the rolling of the spherical magnet. The change is large regardless of the position of the spherical magnet (that is, regardless of the installation direction of the seismic sensor), and the sensitivity is good. That is, like the seismoscope according to claim 3,
In particular, it has high seismic sensitivity in the axial direction of the conductor coil and has directivity.

According to claim 6, 10, 13 or the seismoscope according to claim 16 or 17, which cites this, when the electromagnetic induction electromotive force (or vector sum thereof) exceeds a predetermined threshold value. Since the seismic-sensing signal is output only when the seismic intensity is equal to or higher than a certain level, it is possible to prevent malfunction due to slight vibration.

According to the seismoscope according to claim 7, 11, 14 or claim 16 or 17, which cites this, the electromagnetic induction electromotive force (or vector sum thereof) exceeds a predetermined threshold value for a certain time or more. Since the seismic-sensing signal is output only when the amplitude and period of the shaking are continuously above a certain level, the malfunction prevention effect is further enhanced.

According to the seismoscope of claims 8, 12, 15 or claim 16 or 17, which is cited therein, the electromagnetic induction electromotive force (or vector sum thereof) has a predetermined threshold value within a predetermined time. Since the seismic signal is output only when the number of times exceeds a certain value, that is, when the shaking of a certain magnitude or more continues for a certain period of time, malfunction due to temporary shock, etc. Can be effectively prevented.

According to any one of claims 9 to 15 or the claim 16 or 17 cited therein, the plurality of coils are wound so as to have mutually orthogonal axial directions. At the same time, since each electromagnetic induction electromotive force generated in each coil is individually detected, there is an effect that mounting direction dependency of seismic sensitivity is further reduced.

In particular, any one of claims 13 to 15
According to the seismoscope described in (1), a plurality of coils are wound so as to have mutually orthogonal axial directions, and each electromagnetic induction electromotive force generated in each coil is individually detected, and each electromagnetic induction electromotive force is detected. Since the vector sum of is calculated and whether or not the output of the seismic signal is determined based on the vector sum, the vibration components in each axial direction are combined to be the determination target. Therefore, there is an effect that the magnitude of the vibration of each coil other than the axial direction is correctly evaluated, and the reliability of the vibration is improved.

According to the vibration-sensing device of the seventeenth aspect, since the viscous fluid is enclosed in the spherical cavity, the viscous fluid acts as a damper and the movement of the spherical magnet is suppressed to some extent.
Therefore, it is particularly effective in preventing malfunction.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing a configuration of a main part of a seismoscope according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining an operation example of a determiner in the seismoscope of FIG.

FIG. 3 is a diagram showing an example of changes in electromagnetically induced electromotive force caused by an earthquake.

FIG. 4 is a diagram showing an example of a change in electromagnetic induction electromotive force caused by a temporary impact.

5 is a flowchart for explaining another operation example of the determiner in the seismoscope of FIG.

FIG. 6 is a partial cross-sectional view showing an internal state of the seismoscope when the installation direction of the seismoscope of FIG. 1 is changed.

FIG. 7 is a partial cross-sectional view showing the configuration of a main part of a seismoscope according to another embodiment of the present invention.

8 is a block diagram illustrating a configuration example of a determination unit in the seismoscope of FIG. 7.

9 is a block diagram illustrating another configuration example of the determination unit in the seismoscope of FIG. 7.

FIG. 10 is a partial cross-sectional view showing the configuration of a main part of a seismoscope according to another embodiment of the present invention.

FIG. 11 is a partial cross-sectional view showing the configuration of a main part of a seismoscope according to another embodiment of the present invention.

[Explanation of symbols]

10, 30, 50, 60 Sensor 11 Spherical 12 Spherical cavity 13 Spherical shell 14 Spherical magnet 15, 15 'Coil winding member 16, 16', 16 _x , 16 _y , 16 _z , 43 Conductor coil 17, 17 _x , 17 _y , 17 _z electromotive force detection unit 18 seismic signal 19, 39, 39 ′ determination unit 32 _x , 32 _y , 32 _z , 35 determination circuit 33 OR gate 34 vector sum operation unit

Claims (17)

[Claims] 1. A spherical cavity body having a spherical cavity surrounded by a spherical surface therein, a spherical magnet rotatably housed in the spherical cavity of the spherical cavity body, and a rolling magnet of the spherical magnet. And a magnetic flux change detecting means for detecting a change in magnetic flux distribution caused by movement. 2. The magnetic flux change detecting means is at least wound around the outer surface of the spherical cavity, and a conductive wire coil portion for generating an electromagnetic induction electromotive force according to a change in magnetic flux penetrating the self, and the conductive wire coil portion. And an electromotive force detecting means for detecting an electromagnetic induction electromotive force generated by the electromotive force.
The seismic device described. 3. The first coil wound around the conductive wire coil so as to have at least an axis passing through substantially the center of the spherical cavity of the spherical cavity, and the same coil as the first coil. 3. A second coil, which is wound on opposite sides of the spherical cavity body so as to sandwich the spherical cavity so as to have, and includes a second coil connected in phase with the first coil. The seismic device described. 4. The conductive wire coil portion includes at least a coil wound around the central portion so as to surround the spherical cavity itself of the spherical cavity body. Seismic device. 5. The determining means according to claim 2, further comprising: determining means for determining whether or not to output a seismic signal indicating that an earthquake has been detected, according to the detection result of the electromotive force detecting means. Seismic device. 6. The determination means makes a determination to output the seismic signal when the electromagnetic induction electromotive force detected by the electromotive force detection means exceeds a predetermined threshold value. The seismoscope according to claim 5. 7. The determining means determines that the seismic signal is output when the electromagnetic induction electromotive force detected by the electromotive force detecting means exceeds a predetermined threshold value for a certain time or more continuously. The seismoscope according to claim 5, wherein 8. The determining means counts the number of times the electromagnetic induction electromotive force detected by the electromotive force detecting means exceeds a predetermined threshold value within a predetermined time, and when the count value exceeds a certain value. The seismoscope according to claim 5, wherein the seismic sensor is determined to output the seismic signal. 9. The conductive wire coil portion includes at least a plurality of coils wound so as to have mutually orthogonal axial directions and individually generating electromagnetic induction electromotive force, and the electromotive force detection means includes respective coils. The seismoscope according to claim 5, wherein each electromagnetic induction electromotive force generated by the electromagnetic wave is individually detected. 10. The determination means outputs the seismic signal when any one of the electromagnetic induction electromotive forces detected for each coil by the electromotive force detection means exceeds a predetermined threshold value. 10. The determination according to claim 9 is performed.
The seismic device described. 11. The determination unit is configured to detect the sensitivity when any one of the electromagnetic induction electromotive forces detected for each coil by the electromotive force detection unit continuously exceeds a predetermined threshold value for a predetermined time or more. The seismoscope according to claim 9, wherein it is determined that a seismic signal is to be output. 12. The determination means counts the number of times that the electromagnetic induction electromotive force detected for each coil by the electromotive force detection means exceeds a predetermined threshold value within a predetermined time. The seismoscope according to claim 9, wherein it is determined that the seismic signal is output when one of the seismic signals exceeds a certain value. 13. The seismic-sensing unit determines the vector sum of electromagnetic induction electromotive forces detected for each coil by the electromotive force detection unit, and the vector sum exceeds a predetermined threshold value. The seismoscope according to claim 9, wherein a determination is made to output a signal. 14. The determination means obtains a vector sum of electromagnetic induction electromotive forces detected for each coil by the electromotive force detection means, and the vector sum continuously exceeds a predetermined threshold value for a predetermined time or more. 10. The seismic sensitive device according to claim 9, wherein the seismic sensitive signal is determined to be output when the seismic sensitive signal is output. 15. The determination means obtains a vector sum of electromagnetic induction electromotive forces detected for each coil by the electromotive force detection means, and the number of times the vector sum exceeds a predetermined threshold value within a predetermined time. 10. The seismic sensitive device according to claim 9, wherein the seismic sensitive signal is determined to be output when the count value exceeds a certain value. 16. The spherical hollow body is a spherical shell body having a spherical outer peripheral surface.
The seismoscope according to any one of 1. 17. The seismoscope according to claim 1, wherein a viscous fluid is enclosed in the spherical cavity of the spherical cavity body.