JPH09273960A - Seismoscope and seismic detector using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a higher detection accuracy of a seismoscope by precisely detecting characteristics of vibration. SOLUTION: This seismoscope 1 comprises a housing container 3, a weight 2 supported by at least three vibration detectors 4a, 4b and 4c fixed on the bottom surface of the housing container and can precisely detect the characteristics of vibration with a simple construction. This enables detection distinguishing vibration attributed to earthquake or the like from mere vibration by an impact.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic detector for detecting an earthquake and the like and an earthquake detector using the same.

[0002]

2. Description of the Related Art A conventional seismic sensor 100 of this type is shown in FIG.
As shown in FIG.
The configuration is composed of a spherical weight 103 held by No. 2 and a switch 104 whose electric contact is opened and closed by the load of this weight (Japanese Patent Laid-Open No. 61-160026). When vibration such as an earthquake is transmitted to the storage container 101, the spherical weight 103 moves vertically or horizontally from the mortar-shaped bottom portion 102. By this movement, the lever 105 of the switch 104
The load of the spherical weight 103 applied to the load transmission rod 106 that was pushing down is removed. As a result, the switch 104 operates, the terminals 107a and 107b are turned on and off, and it is detected that vibration is generated.

[0003]

However, although the conventional seismoscope can detect the presence or absence of vibration, it cannot accurately detect the characteristics of vibration such as the magnitude of vibration. In addition, there is a problem that it is impossible to detect the vibration in the vertical direction and the vibration in the horizontal direction separately. Since the characteristics of vibration cannot be accurately detected, there is a problem that it is not possible to determine whether the vibration is due to an earthquake or just due to a shock.

[0004]

In order to solve the above-mentioned problems, the present invention comprises a storage container and a weight supported by a plurality of vibration detection elements fixed to the storage container.

According to the above invention, since the weight that moves due to vibration is supported by the vibration detecting element from at least three directions, the magnitude of vibration and the vibration component in the horizontal or vertical direction are separated. Can be detected.
Further, the seismic detector using this seismic detector can detect the vibration component and the intensity, so that it becomes a higher-performance seismic detector.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention comprises a storage container and a weight fixed to the bottom surface of the storage container and supported by at least three vibration detecting elements.

Further, the storage container and the weight fixed to the ceiling surface of the storage container are suspended from at least three vibration detecting elements.

With this configuration, when the weight changes due to vibration, for example, in the case of vertical vibration, in-phase vibration components are generated in the three vibration detecting elements. Further, in the case of horizontal vibration, vibration components having different phases are generated in the three vibration detecting elements. Therefore, not only the magnitude of the vibration but also the horizontal and vertical components of the vibration can be detected separately.

Further, the storage container and the weight fixed to the bottom surface and the ceiling surface of the storage container are supported from above and below by at least two vibration detecting elements.

With this configuration, by detecting the magnitude and phase of the vibration detected by the two vibration detecting elements, not only the magnitude of the vibration but also the horizontal and vertical components of the vibration can be detected separately. You can

The storage container and the weight supported by a cylindrical piezoelectric vibration detecting element having at least three divided electrodes fixed to the bottom surface of the storage container are used.

Further, the storage container and the weight suspended from a cylindrical piezoelectric vibration sensing element having at least three divided electrodes fixed to the ceiling surface on the bottom surface of the storage container are used.

With this structure, when vibration occurs and the weight moves, a voltage is generated in the piezoelectric vibration detecting element along with the movement of the weight. Therefore, it becomes possible to control the strength / phase detecting means for detecting the vibration only when the vibration occurs and the signal judging means for judging the detected signal, and as a result, a seismoscope with low power consumption is configured. be able to.

Further, the storage container and the weight supported from above and below by a cylindrical piezoelectric vibration detecting element fixed to the bottom surface and the ceiling surface of the storage container and having at least three divided electrodes are adopted.

With this configuration, it is possible to accurately detect the vibration characteristic with a simpler structure in which the weight is supported by the upper and lower cylindrical piezoelectric type vibration detection elements. Therefore, the vibration detection performance is improved. Further, it is possible to configure a seismic sensor that consumes less power.

Further, the seismoscope according to any one of claims 1 to 6, and an intensity / phase detecting means for detecting intensity / phase components of respective signals of a vibration detector constituting the seismic detector, It is configured to include a signal discriminating means for discriminating the detected signal.

With this configuration, since the magnitude of an earthquake and the vertical and horizontal components of vibration can be detected, it is possible to distinguish between an earthquake and vibration due to a simple shock, and it is possible to detect an earthquake with few malfunctions.

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a sectional view of a seismoscope 1 according to a first embodiment of the present invention. Reference numeral 2 denotes a weight installed in the storage container 3 which can be displaced by vibration. Reference numerals 4a, 4b, and 4c denote three coil-shaped vibration detecting elements installed substantially vertically on the bottom surface of the storage container 3. In this vibration detecting element, a strain resistance wire or the like is formed into a coil shape so that the elastic change easily occurs. The weight 2 is a conductive metal ball, and 5 is a flexible lead wire whose weight is negligibly small. 6
And 7a, 7b, and 7c indicate connection terminals. With such a configuration, when the storage container 3 is vibrated, the elastically supported weight 2 is displaced vertically and horizontally according to the vibration. For example, when vibration is applied up and down,
Since the weight 2 vibrates in the vertical direction, the coil-shaped vibration detection elements 4a, 4b, and 4c respectively expand and contract vertically in the same cycle. Therefore, the coil-shaped vibration detecting elements 4a, 4b, and 4c exhibit the same phase resistance change in synchronization with the vibration. By detecting this resistance change from the connection terminal, the displacement of the weight 2 can be detected, and the vibration can be detected.
When left and right vibrations are applied to the storage container 3, the weight 2
Will vibrate left and right. In this case, the coil-shaped vibration sensing element in the vibration direction bears most of the weight of the weight 2 and is compressed. On the contrary, the coil-shaped vibration sensing element in the opposite direction is stretched because the load of the weight 2 is reduced. Therefore, the resistance changes of the coil-shaped vibration sensing elements 4a, 4b, and 4c show resistance changes of different phases and magnitudes. As described above, the coil-shaped vibration detecting element 4
By detecting the magnitude of resistance change and the phase relationship of a, 4b, and 4c, it is possible to detect not only the magnitude of vibration but also the vibration in the horizontal direction and the vibration in the vertical direction.

(Embodiment 2) FIG. 2 is a sectional view of a seismoscope 8 according to a second embodiment of the present invention. Reference numeral 9 denotes a weight that is placed in the storage container 10 and can be displaced by vibration. 11a, 11
Reference numerals b and 11c denote three coil-shaped vibration detection elements installed substantially vertically on the ceiling of the storage container 10. In this vibration detecting element, a strain resistance wire or the like is formed in a coil shape similarly to the first embodiment so that the elastic change can be easily caused. The weight 9 is a conductive metal ball, and the reference numeral 12 is a flexible lead wire whose weight is negligible. Reference numerals 13 and 14a, 14b and 14c denote connection terminals. With such a configuration, when vibration is applied to the storage container 10, the same operation as that of the first embodiment is obtained, and the same effect is obtained.

However, in this case, since the weight is hung from the ceiling portion, it is not necessary to support the weight, and it is possible to achieve higher sensitivity to horizontal vibration. Also, the weight 9 can be easily installed.

In the first and second embodiments, the vibration detecting elements are arranged substantially in parallel, but the same action and effect can be obtained by arranging them in a triangular pyramid shape like a tripod of a camera.

(Embodiment 3) FIG. 3 is a sectional view of a seismoscope 15 according to a third embodiment of the present invention. Reference numeral 16 denotes a weight that is placed in the storage container 17 and can be displaced by vibration. 18 and 19 are upper and lower 2 fixed to the ceiling and bottom of the storage container 17.
2 illustrates a coiled vibration sensing element. In this vibration detecting element, a strain resistance wire or the like is formed in a coil shape in the same manner as in Examples 1 and 2, so that elastic change easily occurs. It should be noted that the weight 16 is a conductive metal ball, and 20 indicates a flexible lead wire whose weight is so small that it can be ignored. 21, 2
Reference numerals 2 and 23 denote connection terminals for the vibration detecting elements 18 and 19 and the lead wire 20, respectively. A seismoscope 1 with such a configuration
When vibration is applied to 5, the weight 16 vibrates up and down, for example, in the case of vertical vibration. Therefore, when the upper vibration detecting element 18 is compressed by the weight 16, the lower vibration detecting element 19 is expanded. For this reason, the upper and lower vibration detecting elements change in resistance in opposite directions. That is, one increases the resistance and the other decreases. In the case of horizontal vibration, the upper and lower vibration sensing elements are simultaneously stretched together with the lateral displacement of the weight 16. At this time, the resistance changes generated in the vibration detecting elements 18 and 19 are the same. That is, in both cases, the resistance increases or decreases. By separately detecting the resistance change of the upper and lower vibration detecting elements in this manner, not only the magnitude of the vibration but also the horizontal and vertical components of the vibration can be separately detected. Since the configuration is simpler than that of the first and second embodiments and not only the magnitude of vibration but also the horizontal component and the vertical component can be detected separately, it is possible to easily determine whether it is an earthquake or a simple impact. .

(Embodiment 4) FIG. 4 is a sectional view of a seismoscope 24 according to a fourth embodiment of the present invention. Reference numeral 25 denotes a weight that is placed inside the storage container 26 and can be displaced by vibration. Reference numeral 27 denotes a cylindrical piezoelectric vibration detecting element that supports the weight 25, and is fixed to the bottom surface of the storage container 26. This piezoelectric vibration sensing element has a structure in which fine particles made of a piezoelectric material are dispersed in synthetic rubber to have excellent flexibility. Reference numeral 28 is an internal electrode of the piezoelectric vibration sensing element 27, and 29a, 29b, 29c (2
Reference numeral 9c indicates an external electrode divided into three in the axial direction (not shown). Reference numerals 30, 31a and 31b denote respective lead wires, which are connected to the connection terminals 32, 33a and 33b. Reference numeral 34 designates a synthetic rubber portion containing a piezoelectric material between the internal electrode and the external electrode, and 35 designates a hollow cylindrical portion. FIG. 5 shows a partially enlarged view of the cylindrical piezoelectric vibration detecting element 27. 28 is an internal electrode which is common.
Further, 29a and 29b are external electrodes divided into three in the axial direction. When the synthetic rubber portion 34 is strained, the inner electrode 28 and the outer electrode 29a or 29a are generated due to the piezoelectric property.
A voltage is generated at b. The tip of the cylindrical piezoelectric vibration sensing element 27 was shaped like a mortar and the weight 25 was fixed. With such a configuration, when vibration is applied to the storage container 26, the weight 25 is displaced while being constrained by the cylindrical piezoelectric vibration detection element 27. Due to the displacement of the weight 25, the cylindrical piezoelectric vibration detecting element 27 is distorted, and a voltage is generated between the internal electrode and the external electrode. For example, when the weight 25 is vertically displaced, the cylindrical piezoelectric vibration sensing element 27 is vertically expanded and contracted and compressed. Therefore, 27 will be radially compressed and expanded. That is, the thickness increases or decreases. Therefore, in synchronization with this operation, the inner electrode 28 and the outer electrodes 29a, 29b, 29
A positive voltage or a negative voltage will be generated between c.
The voltages generated at this time are synchronously generated in the same phase.
The generated voltage depends on the magnitude of the applied strain, that is, the magnitude of the vibration. When the weight 25 is displaced left and right, the cylindrical piezoelectric vibration sensing element 27 is displaced left and right. Therefore, the part in the displacement direction is compressed by the weight 25, and the part in the opposite direction is expanded. In synchronization with this operation, positive voltage and negative voltage are generated between the inner electrode 28 and the outer electrodes 29a, 29b, 29c. In this case, since the generated voltage depends on the displacement direction, it may have the same phase or an opposite phase.
Thus, the inner electrode 28 and the outer electrodes 29a, 29b, 2
By separately detecting the positive voltage and the negative voltage between 9c, the magnitude of vibration and the vertical component and the horizontal component can be detected separately.

(Embodiment 5) FIG. 6 is a sectional view of a seismoscope 35 according to a fifth embodiment of the present invention. Reference numeral 36 denotes a weight that is placed in the storage container 37 and can be displaced by vibration. Reference numeral 38 denotes a cylindrical piezoelectric vibration detecting element for suspending the weight 36, which is fixed to the ceiling surface of the storage container 37 almost vertically. With this configuration, when vibration is applied to the storage container 37, the internal electrode 39 and the external electrode 40 are generated as in the fourth embodiment.
A voltage is generated at a and 40b. The generated voltage is supplied to the connecting terminals 43, 44 via the lead wires 41, 42a, 42b.
It is detected from a and 44b. Similar to the fourth embodiment, by detecting the magnitude of the voltage generated in each electrode and the phase relationship between them, not only the magnitude of the vibration but also the vertical component and the horizontal component thereof can be detected separately.

(Embodiment 6) FIG. 7 is a sectional view of a seismoscope 45 according to a sixth embodiment of the present invention. Reference numeral 46 denotes a weight installed in the storage container 47 and capable of being displaced by vibration. Reference numerals 48 and 49 denote upper and lower cylindrical piezoelectric vibration detecting elements that support the weight 46 from above and below, and are fixed substantially vertically to the ceiling surface portion and the bottom surface portion of the storage container 47. With this configuration, when vibration is applied to the storage container 47, the fourth and fifth embodiments are performed.
Similarly, the upper and lower cylindrical piezoelectric vibration sensing elements 48, 4
A voltage is generated between the inner electrode and the outer electrode of No. 9. These voltages are taken out and detected from the connection terminals installed on the ceiling surface or the bottom surface of the storage container 47. Therefore, not only the magnitude of the vibration but also the vertical component and the horizontal component thereof can be distinguished and detected from the magnitude and phase relationship of the voltages.

In Examples 4 to 6, the piezoelectric vibration detecting element was used in the form of a cylinder, but this is for the purpose of simplifying the structure, and if it is composed of at least three columns, the present invention will be obtained. The same effect can be obtained.

(Seventh Embodiment) FIG. 8 is a block diagram of an earthquake detector according to a seventh embodiment of the present invention. The signal from any one of the seismic sensors 45 in the above-described first to sixth embodiments is input to the intensity / phase detector 46 as the intensity / phase detector. When the vibration detecting element of the seismic sensor 45 is composed of the strain resistance wire shown in Examples 1 to 3, the input portion of the intensity / phase detector 46 has the structure shown in FIG. Further, when the vibration detecting element of the seismic sensor 45 is composed of the cylindrical piezoelectric vibration detector shown in Examples 4 to 6, the input portion of the intensity / phase detector 46 has the configuration shown in FIG. Become. The signal output from the intensity / phase detector 46 is transmitted to the signal discriminator 47 in order to discriminate whether it is vibration such as an earthquake or vibration due to a simple impact.

In FIG. 9, for example, when the seismoscope 15 shown in the third embodiment is used, 48 is a power supply voltage (voltage Vb),
49 is a fixed resistor (resistor Rc), 21 is a connection terminal,
Reference numerals 8 (resistors Ru) and 19 (resistors Rd) denote upper and lower vibration detectors, and 23 denotes a connection terminal connected to the conductive weight 16. Reference numeral 50 indicates a grounding portion. The resistance changes when the characteristics of 18 and 19 are extended are dRu and dRd, for example. This time,
If the weight 16 vibrates up, the resistance of 18 is Ru
The resistance of + dRu, 19 becomes Rd-dRd. At this time, if the characteristics of 18 and 19 are the same, the resistance changes of 18 and 19 cancel each other out, so that the voltage generated at the connection terminal 21 does not change. On the other hand, in the voltage generated at the connection terminal 18, the resistance of 18 increases and the resistance of 19 decreases,
The sensitivity will be doubled and lowered. Also, the weight 16
When 18 moves in the horizontal direction, 18 and 19 are stretched at the same time, so that the respective resistances are Ru-dRu and Rd.
-DRd. In this case, the voltage generated at the connection terminal 21 decreases with double the sensitivity.
By discriminating the change of the generated voltage by the signal discriminator 47, the variation of the weight 16 can be detected by distinguishing the size and the horizontal direction or the vertical direction.
Since the vibration characteristics can be detected in detail in this way, it is possible to determine whether the vibration is due to an earthquake or just due to a shock.

Next, referring to FIG. 10, for example, when the seismoscope 24 shown in the fourth embodiment is used, 51 is a power supply voltage (voltage Vb), 52 is a fixed resistor (resistor Rc), and 53 is an output terminal. Reference numeral 54 is a signal converter such as a high impedance FET, and input 55 is connected to one of the external electrodes of the cylindrical piezoelectric vibration sensing element 27. Reference numeral 56 is a grounding portion. As a result of the vibration, a voltage is generated in the cylindrical piezoelectric vibration detecting element 27, and 54 is rendered conductive for the first time, so that a current flows through the fixed resistor 52. Therefore, a large voltage change appears at the output terminal 53. By detecting the magnitude or the phase of this voltage with the following signal discriminator, the vibration characteristic can be detected in detail.

In this case, the current flowing through the resistor 52 is negligibly small until vibration occurs and a voltage is applied to 55. For this reason, the configuration is optimal for a battery-powered earthquake detector. That is, it suffices to consume electric power only when vibration occurs to detect the characteristics of the vibration in detail, and hardly consume electric power when there is no vibration.

[0031]

As is clear from the above description, the seismoscope of the present invention has the following effects.

(1) A structure comprising a storage container and a weight fixed to the bottom of the storage container and supported by at least three vibration detecting elements, and the storage container, and at least 3 fixed to the ceiling surface of the storage container. Since the weight is suspended from the vibration detecting element of the book, the magnitude of vibration and its horizontal and vertical components can be detected separately.

(2) Since the storage container and the weight fixed to the bottom surface and the ceiling surface of the storage container are supported by at least two vibration detecting elements from above and below, the vibration is simple and sensitive. Can be detected. Further, since the weight is supported from above and below, the installation becomes easy.

(3) A storage container and a storage container, and a storage container and a weight supported by a cylindrical piezoelectric vibration sensing element having at least three-divided electrodes fixed to the bottom surface of the storage container. And a storage container fixed to the ceiling surface on the bottom surface of the storage container, and a storage container including a weight suspended from a cylindrical piezoelectric vibration sensing element having at least three-divided electrodes and fixed to the bottom surface and the ceiling surface of the storage container. Since it is composed of a weight supported from above and below by a cylindrical piezoelectric type vibration detection element having at least three divided electrodes, the magnitude of vibration and its horizontal and vertical components are detected separately. it can. In addition, it is possible to construct a seismoscope that has a simple configuration, is easy to install, and consumes less power.

Further, the earthquake detector of the present invention has the following effects. (4) The intensity of each signal of the seismoscope according to any one of claims 1 to 6 and the vibration detection element that constitutes the seismoscope.
Since it consists of an intensity / phase detector that detects the phase component and a signal discriminator that discriminates the detected signal, not only the magnitude of the vibration but also the horizontal component and the vertical component are detected with high sensitivity. Therefore, it is possible to distinguish between an earthquake and a vibration caused by a simple impact. Further, when the seismoscope according to any one of claims 4 to 6 is used, an earthquake detector excellent in power saving can be configured. Therefore,
It is possible to realize a long-life earthquake detector driven by batteries.

[Brief description of drawings]

FIG. 1 is a sectional view of a seismoscope according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a seismoscope according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a seismoscope according to a third embodiment of the present invention.

FIG. 4 is a sectional view of a seismoscope according to a fourth embodiment of the present invention.

[Figure 5] Partial enlarged view of the same seismic device

FIG. 6 is a sectional view of a seismoscope according to a fifth embodiment of the present invention.

FIG. 7 is a sectional view of a seismoscope according to a sixth embodiment of the present invention.

FIG. 8 is a block diagram of an earthquake detector according to a seventh embodiment of the present invention.

FIG. 9 is a configuration diagram of an input unit of an intensity / phase detector of an earthquake detector according to a seventh embodiment of the present invention.

FIG. 10 is a block diagram of another input unit of the same intensity / phase detector.

FIG. 11 is a sectional view of a conventional seismic sensor.

[Explanation of symbols]

1,8,15,24,35,45 Seismic sensor 2,9,16,25,36,46 Weight 3,10,17,26,37,47 Storage container 4a, 4b, 4c, 11a, 11b, 11c , 18, 1
9 Vibration detection element 27, 38, 48, 49 Piezoelectric vibration detection element 46 Strength / phase detector 47 Signal discriminator

Claims (7)

[Claims] 1. A seismoscope comprising a storage container and a weight fixed to the bottom surface of the storage container and supported by at least three vibration detecting elements. 2. A seismic sensor comprising a storage container and a weight suspended from at least three vibration detecting elements fixed to the ceiling surface of the storage container. 3. A seismic sensor comprising a storage container and a weight fixed to the bottom surface and the ceiling surface of the storage container and supported from above and below by at least two vibration detecting elements. 4. A seismoscope comprising a storage container and a weight supported by a cylindrical piezoelectric vibration sensing element having at least three divided electrodes fixed to the bottom surface of the storage container. 5. A seismoscope comprising a storage container and a weight suspended from a cylindrical piezoelectric vibration detecting element having at least three divided electrodes fixed to the ceiling surface on the bottom surface of the storage container. 6. A seismoscope comprising a storage container, and a weight supported from above and below by a cylindrical piezoelectric vibration detecting element having at least three divided electrodes fixed to the bottom surface and ceiling surface of the storage container. 7. A seismic detector according to claim 1, and an intensity / phase detector for detecting intensity / phase components of respective signals of a vibration detecting element constituting the seismic detector, An earthquake detector consisting of a signal discriminator that discriminates the detected signal.