JP2015118065A - Seismometer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seismometer capable of easily determining whether or not equipment failure occurs.SOLUTION: A seismometer includes: an acceleration sensor 11 for measuring acceleration due to a tremor, and for outputting the measured acceleration data; and a vibrator 14 for vibrating the acceleration sensor 11. The acceleration sensor 11 is configured to measure acceleration following three measurement axes perpendicular to each other, and the vibrator 14 is arranged to vibrate the accelerator sensor 11 in any direction of those three measurement axes. Also, the seismometer also includes a determination part for acquiring the acceleration data to be output from the acceleration sensor 11 when the vibrator 14 vibrates. The determination part is configured to determine equipment failure on the basis of the waveform of a vibration wave to be obtained from the acceleration data.

Description

  The present invention relates to a seismometer capable of detecting an earthquake shake by an acceleration sensor, and more particularly to a seismometer capable of performing a failure test by including a vibrator.

  Conventionally, seismometers are used in limited fields such as earthquake research, and many are large and expensive. On the other hand, in recent years, the MEMS acceleration sensor has been greatly developed, and it has become possible to make the seismometer small and inexpensive. In addition to this, structural damage detection (SHM) is attracting attention, and it is expected that there will be an increase in demand for installing relatively small and inexpensive seismometers in general buildings and buildings. As a small seismometer using such an acceleration sensor, there exists a thing as described in patent document 1, for example.

JP 2011-202961 A

  Conventional seismometers are often used by researchers and other people familiar with earthquakes and other vibrations. Seismometers may obtain vibration waveforms due to factors other than earthquakes, but whether each vibration waveform is due to seismometer faults or other factors is determined by the experience of each user. It was. However, when seismometers are widely used in general, users are not always familiar with vibration. For this reason, it may be difficult to determine what causes the vibration waveform obtained by the seismometer.

  Factors other than earthquakes that cause seismometers to obtain vibration waveforms include faults in seismometers, improper installation of seismometers, problems specific to measurement points, natural vibrations of buildings, or mechanical vibrations elsewhere This may be due to noise sources. If the seismometer is out of order, repair or replacement by the manufacturer is necessary. If the seismometer is due to other factors, the user needs to respond according to the factor. Therefore, it is necessary to easily determine whether the cause of the vibration waveform is at least due to a failure or other reason.

  The present invention has been made in view of the above problems, and an object thereof is to provide a seismometer that can easily determine whether or not a device failure has occurred.

In order to solve the above-mentioned problem, the seismometer according to the invention of claim 1 is a seismometer having an acceleration sensor that measures acceleration due to shaking and outputs the measured acceleration data.
A vibrator that vibrates the acceleration sensor is provided.

  According to the invention which concerns on Claim 1, it can test about the operation | movement of a seismometer when there is a vibration with a vibrator, and can determine the presence or absence of an equipment failure with the obtained waveform.

  The seismometer according to the invention of claim 2 is configured such that the acceleration sensor can measure acceleration along three measurement axes orthogonal to each other, and the vibrator is in any direction of the three measurement axes. Is also arranged to vibrate the acceleration sensor.

  According to the invention which concerns on Claim 2, it becomes possible to test about all the sensors which comprise an acceleration sensor.

  Furthermore, in the seismometer according to the invention of claim 3, the vibrator is mounted on a substrate on which the acceleration sensor is arranged, and vibrates in at least two orthogonal directions, and one of the vibrating directions is One of the measurement axes of the acceleration sensor is inclined in the same direction as the one measurement axis or with respect to the one measurement axis, and the other of the vibrating directions is perpendicular to the one measurement axis among the measurement axes of the acceleration sensor. It is configured so as to be inclined with respect to one measurement axis.

  According to the invention which concerns on Claim 3, the vibration which contains all the three axial directions for measuring a vibration wave as a vibration component can be given with a vibrator.

  Furthermore, the seismometer according to the invention of claim 4 further includes a determination unit that acquires acceleration data output from the acceleration sensor when the vibrator vibrates, and the determination unit is obtained from the acceleration data. The device failure is determined based on the waveform of the vibration wave generated.

  According to the invention which concerns on Claim 4, it becomes possible to determine and display the presence or absence of an apparatus failure within a seismometer.

  The seismometer according to the invention of claim 5 further includes a transmission unit that transmits acceleration data output from the acceleration sensor to an external determination unit when the vibrator vibrates, and the determination unit Is configured to determine a device failure based on a waveform of a vibration wave obtained from the acceleration data.

  According to the invention which concerns on Claim 5, it becomes possible to determine and display the presence or absence of an equipment failure from the outside of a seismometer.

  Further, the seismometer according to the invention of claim 6 is characterized in that the determination unit determines a device failure based on an amplitude and a frequency of a vibration wave obtained from the acceleration data.

  According to the invention which concerns on Claim 6, it becomes possible to determine the presence or absence of an apparatus failure, and the cause of problem occurrence.

  Furthermore, the seismometer according to the invention of claim 7 is characterized in that the vibrator is configured such that the frequency is variable.

  According to the seventh aspect of the present invention, it is possible to detect the presence or absence of a device failure from the response frequency characteristics by testing the sensor while changing the vibration frequency of the vibrator.

  According to the seismometer according to the present invention, it is possible to easily determine whether the cause of malfunction of the seismometer is due to equipment failure or not, regardless of the user's experience, etc. It is possible to make a determination, and even a user who is not familiar with seismometers can determine what kind of countermeasure is necessary.

It is a perspective view of the seismometer in this embodiment. It is a top view of the board | substrate provided in the main body. It is a perspective view of a vibrator. It is a front view of a vibrator. It is a block diagram of the seismometer of this embodiment. It is a figure showing the time change of the frequency of the vibration which a vibrator generates.

  Embodiments of the present invention will be described in detail with reference to the drawings. In FIG. 1, the perspective view of the seismometer in this embodiment is shown. This seismometer is installed and fixed at an arbitrary location of a building such as a building, and is configured to acquire and output vibration data due to an earthquake.

  As shown in FIG. 1, the seismometer has a main body 1 formed in a box shape and a plate-like fixed surface portion 2 on which the main body 1 is placed. A fixing portion 3 is provided for fixing. On the side surface of the main body 1, an input / output port 4 is formed for inputting a command to a device housed therein or outputting vibration data. In the present embodiment, the input / output port 4 is configured as a LAN port. In order to reliably detect vibration caused by an earthquake, the fixed surface portion 2 needs to abut against the wall surface or floor surface of the building and be firmly attached.

  In FIG. 2, the top view of the board | substrate 10 provided in the main body 1 is shown. Various components constituting the seismometer are mounted on the substrate 10, but only representative components are shown in FIG. 2. The acceleration sensor 11, the reference voltage source 12, and the AD converter 13 are arranged on the substrate 10 as components that constitute the seismometer. Although the acceleration sensor 11 and the AD converter 13 are separated in the present embodiment, a digital output sensor in which these are integrated may be used.

  The acceleration sensor 11 includes an X-axis sensor 11a that detects acceleration in the X-axis direction shown in FIG. 2, a Y-axis sensor 11b that detects acceleration in the Y-axis direction, and a Z-axis sensor 11c that detects acceleration in the Z-axis direction. And have. The X axis, Y axis, and Z axis in FIG. 2 are orthogonal to each other. That is, the acceleration sensor 11 can acquire acceleration data in three axial directions orthogonal to each other.

  A vibrator 14 that can vibrate the entire substrate 10 including the acceleration sensor 11 is disposed on the substrate 10. The vibrator 14 is composed of a vibration motor, and can provide vibration in a plane direction orthogonal to the axial direction of the rotation shaft 14b with rotation. The vibrator 14 is disposed on the substrate 10 so that the rotation axis direction of each of the three measurement axes of the acceleration sensor 11 forms an angle of 45 degrees with respect to the X axis and the Y axis. Is used for testing whether or not acceleration data can be acquired normally.

  FIG. 3 shows a perspective view of the vibrator 14, and FIG. 4 shows a front view of the vibrator 14. As shown in these drawings, the vibrator 14 is integrally provided so as to decenter the base portion 14a placed and fixed on the substrate 10, the rotating shaft 14b rotating with respect to the base portion 14a, and the rotating shaft 14b. And a weight portion 14c. The center of gravity of the rotating shaft 14b is eccentric from the center of rotation by the weight portion 14c, and the vibrator 14 vibrates in a plane direction orthogonal to the axial direction of the rotating shaft 14b as the rotating shaft 14b rotates. That is, the vibrator 14 vibrates in two axial directions orthogonal to the axial direction of the rotating shaft 14b.

  As shown in FIG. 2, the vibrator 14 is inclined so that the rotation axis direction forms an angle of 45 degrees with respect to the X axis and the Y axis among the measurement axes of the acceleration sensor 11. If one of the two axial directions that are the vibration directions of the vibrator 14 is the Z-axis direction, the other is inclined with respect to the X-axis and the Y-axis, so the vibration component in the X-axis direction and the vibration in the Y-axis direction. Any of the components can be generated. That is, a vibration component can be generated by the vibrator 14 in any of the three axial directions measured by the acceleration sensor 11. Accordingly, any of the X-axis sensor 11a, the Y-axis sensor 11b, and the Z-axis sensor 11c can be vibrated by the vibrator 14, and acceleration data can be acquired.

  FIG. 5 shows a block diagram of the seismometer of the present embodiment. As shown in this figure, a dummy sensor 11 d is provided in parallel with each sensor constituting the acceleration sensor 11. The output from the dummy sensor 11d is used for offset correction and noise removal.

  The X-axis sensor 11a, the Y-axis sensor 11b, the Z-axis sensor 11c, and the dummy sensor 11d are each connected to the preamplifier 26. Since each sensor has a high output impedance, impedance conversion is necessary, and the preamplifier 26 performs the impedance conversion and constitutes an antialiasing filter. Each preamplifier 26 is connected to the AD converter 13 and the output from the acceleration sensor 11 is output as digital data. A highly accurate reference voltage source 12 is connected to the AD converter 13.

  The output from the acceleration sensor 11 is input to the CPU 20. A nonvolatile memory 21 is connected to the CPU 20. The memory 21 stores sensitivity correction values of the sensors constituting the acceleration sensor 11 and the like. The sensitivity correction value is measured in advance before shipment from the factory, and is applied to the output from each sensor. The CPU 20 incorporates a LAN network controller and is connected to the LAN network 23 via the input / output unit 22 which is a LAN physical layer device. Thereby, the seismometer can transmit the acquired acceleration data to the outside, and can perform a test or the like by the vibrator 14 according to a command from the outside. Note that a wireless LAN or the like may be used for connection to the LAN network 23.

  The seismometer is provided with a power source or current source 24 for driving the vibrator 14. As the power source or current source 24, a power source or a current source 24 that is insulated from a device power source that operates the entire seismometer is used. The power source or current source 24 is connected to the vibrator 14 via a relay 25 controlled by the CPU 20. That is, the drive of the vibrator 14 is controlled by the CPU 20. The test by driving the vibrator 14 may be performed by operating a switch (not shown) provided in the seismometer itself, or may be performed by giving an external command via the LAN network 23. . Instead of the relay 25, another type of component may be employed as long as the electrical connection state can be switched, such as a semiconductor relay, a transistor, an FET, or an analog switch.

  As described above, since the vibrator 14 is arranged so that any of the X-axis sensor 11a, the Y-axis sensor 11b, and the Z-axis sensor 11c can vibrate, the vibrator 14 is driven by the control of the CPU 20. Then, acceleration data is output from each sensor, and the CPU 20 obtains vibration wave data from the acceleration data in the three-axis directions. Based on the waveform of the vibration wave data, specifically, the amplitude and frequency of the vibration wave, the presence / absence of a device failure is determined. The determination unit that performs the determination may be provided as a function of the CPU 20 or may be provided in an external device connected via the LAN network 23.

  In the determination unit, the original vibration wave data obtained by the acceleration sensor 11 by the vibrator 14 is compared with the actually obtained vibration wave data to detect the presence or absence of a device failure. For example, when the amplitude of the actually obtained vibration wave data is less than or equal to the original amplitude, it is determined that a device failure has occurred due to sensor sensitivity degradation. If there is an abnormality such as a random waveform pattern of vibration wave data, it is determined that a device failure has occurred due to a circuit failure. When a harmonic such as double and a subharmonic such as ½ are detected by vibration frequency peak transition of vibration wave data, the seismometer is loosely fixed to the building, It is determined that there is no equipment failure. On the other hand, if the actually obtained vibration wave data matches the original vibration wave data pattern within a predetermined range, it is determined that no device failure has occurred. Further, the vibrator 14 is configured to be able to change the vibration frequency, and by testing the acceleration sensor 11 by changing the vibration frequency of the vibrator 14, the presence / absence of equipment failure is determined from the response frequency characteristics. Can also be determined.

  In FIG. 6, the figure showing the time change of the frequency of the vibration which the vibrator | oscillator 14 generate | occur | produces is shown. FIG. 6A shows a case where the frequency does not change with time and is constant. FIG. 6B shows a case where the frequency is continuously changed so that the frequency gradually increases with time. In this case, a more detailed cause of the failure can be determined based on the response frequency characteristic. FIG. 6C illustrates a case where the power supply to the vibrator 14 is pulsed and vibration is performed intermittently. In this case, power saving can be achieved. FIG. 6D illustrates a case where the electrode supply to the vibrator 14 is changed to a pulse shape and the frequency is gradually increased. In this case, it is possible to determine the cause of the failure in more detail based on the response frequency characteristic while saving power.

  When the determination unit is provided in the seismometer, the display unit (not shown) for displaying the determination result is provided in the main body, so that the user can easily know the determination result. In addition, when the determination unit is provided outside the seismometer, the determination result can be appropriately displayed on the device having the determination unit.

  Thus, by providing the vibrator 14, it is possible to easily perform a test by actually oscillating the acceleration sensor 11, and based on the vibration wave data obtained thereby, the determination unit determines whether there is a device failure. And the cause of the malfunction can be determined. As a result, when there is a malfunction in the seismometer, it is possible to easily determine whether the cause is due to equipment failure or not, regardless of the user's experience, etc. It is possible to judge even a user who is not familiar with seismometers.

  Further, by arranging the rotation axis of the vibrator 14 so as to be inclined with respect to the measurement axis direction of two sensors of the acceleration sensor 11, vibration components are generated in any of the three axis directions measured by the acceleration sensor 11. And all sensors can be tested. In this embodiment, the rotational axis direction of the vibrator 14 is arranged so as to be inclined by 45 degrees with respect to the X axis and the Y axis, respectively, but other inclination angles may be used. You may arrange | position so that it may incline with respect.

  Although the embodiment of the present invention has been described above, the application of the present invention is not limited to this embodiment, and can be applied in various ways within the scope of its technical idea. For example, although a vibration motor is used as the vibrator 14 in the present embodiment, any other device that generates vibration may be used as long as it can apply vibration to the acceleration sensor 11.

DESCRIPTION OF SYMBOLS 1 Main body 2 Fixed surface part 3 Fixed part 4 Input / output port 10 Board | substrate 11 Acceleration sensor 11a X-axis sensor 11b Y-axis sensor 11c Z-axis sensor 12 Reference voltage source 13 AD converter 14 Vibrator 14a Base 14b Rotating shaft 14c Weight part 20 CPU
21 Memory 22 Input / Output Unit 23 LAN Network 24 Power Supply or Current Source 25 Relay 26 Preamplifier

Claims (7)

In a seismometer having an acceleration sensor that measures acceleration due to shaking and outputs the measured acceleration data,
A seismometer comprising a vibrator for vibrating the acceleration sensor.   The acceleration sensor is configured to measure acceleration along three measurement axes orthogonal to each other, and the vibrator is arranged to vibrate the acceleration sensor in any direction of the three measurement axes. The seismometer according to claim 1.   The vibrator is mounted on a substrate on which the acceleration sensor is arranged, and vibrates in at least two orthogonal directions. One of the vibrating directions is one of the measurement axes of the acceleration sensor. In the same direction or inclined with respect to the one measuring axis, the other of the vibrating directions is arranged so as to be inclined with respect to two measuring axes orthogonal to the one measuring axis among the measuring axes of the acceleration sensor. The seismometer according to claim 2.   A determination unit that acquires acceleration data output from the acceleration sensor when the vibrator vibrates; and the determination unit determines a device failure based on a waveform of a vibration wave obtained from the acceleration data; The seismometer according to any one of claims 1 to 3.   The apparatus further includes a transmission unit that transmits acceleration data output from the acceleration sensor when the vibrator vibrates to a determination unit provided outside, and the determination unit converts the vibration wave waveform obtained from the acceleration data into a waveform. The seismometer according to any one of claims 1 to 3, wherein an equipment failure is determined based on the seismometer.   The seismometer according to claim 4, wherein the determination unit determines a device failure based on an amplitude and a frequency of a vibration wave obtained from the acceleration data. The seismometer according to claim 1, wherein the vibrator is configured to have a variable frequency.

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