JP2016038275A - Vibration detection device and vibration detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow for vibration detection with higher accuracy in a vibration detection device in which a sensor which detects vibration and a power generation mechanism which generates power by vibrating a movable part are integrally configured.SOLUTION: There is provided a vibration detection method for detecting vibration of a facility using a vibration detection device comprising a vibration sensor which detects vibration of the facility and a power generation unit which generates power by vibrating a movable part according to the vibration of the facility. The vibration detection method includes the steps of: performing frequency analysis processing for extracting a frequency component corresponding to vibration of the movable part on the basis of a waveform representing the voltage generated by the power generation unit; and performing filter processing for removing the extracted frequency component corresponding to vibration of the movable part from a vibration signal representing the vibration of the facility detected by the vibration sensor.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a vibration detection device and a vibration detection method.

  As part of equipment maintenance work in a factory such as a steelmaking plant, the state of the equipment is detected by various sensors, and an abnormality of the equipment is determined based on the detected values (hereinafter also referred to as equipment diagnosis work). Has been done. For example, in equipment diagnosis work, a vibration detection device including a vibration sensor capable of detecting vibration such as an acceleration sensor is attached to an operating equipment, and based on a vibration signal representing the vibration of the equipment, which is an output value of the vibration sensor. The abnormality of the equipment is judged.

  Here, when the vibration detection device is attached to the facility, a cable for supplying power to the vibration detection device, a cable for transmitting a vibration signal detected by the vibration detection device to an external device, or the like is not used. It is preferable. This is because the presence of these cables around the equipment may hinder the smooth operation of the equipment. In addition, when the vibration signal is transmitted by wire, there is a risk of the cable being disconnected due to the cable being used under vibration conditions, especially in locations where the equipment to be diagnosed and the external device are separated. In such a case, the distance for laying the cable becomes long, and there is a concern about an increase in cost. Therefore, the vibration detection device is integrally equipped with a vibration sensor, a power supply device such as a battery, and a transmission device for transmitting a vibration signal to an external device, and can be connected to a wired external device by a cable or the like. There is a need to do as little as possible.

  However, the more complicated the configuration of the vibration detection device is, the larger the power consumption becomes. Therefore, the battery is consumed rapidly, and it may be difficult to continuously drive for a long period of time. In the facility diagnosis work, depending on the diagnosis item, it may be required to acquire a vibration signal for a long period of time, so a situation in which the battery needs to be frequently replaced is not preferable.

  Therefore, a technique for incorporating a power generation mechanism into a vibration detection apparatus that wirelessly transmits a detected signal to an external device has been developed. For example, in Patent Document 1, the vibration detection device attached to the bearing detects the temperature and vibration of the bearing, wirelessly transmits the detected data to an external data monitoring device, and based on the rotational motion of the bearing. A technique for driving the vibration detection device itself by the generated power is disclosed. Further, for example, Patent Document 2 includes a vibration detection device that has a beam-like movable part, detects vibration by vibration of the movable part, and is driven by electric power generated based on the vibration of the movable part. It is disclosed. According to the techniques described in Patent Documents 1 and 2, since a power generation mechanism is incorporated in the vibration detection device, and the vibration detection device itself is driven by the power generated by the power generation mechanism, continuous data detection for a long period of time is possible. It becomes possible.

JP 2004-126852 A JP 2011-160612 A

  However, in the technique described in Patent Document 1, since power generation is performed based on the rotational motion in the bearing to which the vibration detection device is to be attached, power generation cannot be performed when mounted on a portion other than the bearing. . Further, as in the technique described in Patent Document 2, when the sensor that detects vibration and the power generation mechanism that generates power based on the vibration of the movable part are configured as an integrated device, the movable part in the power generation mechanism May affect the detected value of the sensor. If the influence of the vibration of the movable part in the power generation mechanism is large, for example, a signal representing a minute vibration that can be used as a judgment for equipment abnormality is mixed with a signal representing the vibration of the movable part, and the equipment diagnosis can be performed with high accuracy. There is no fear.

  In particular, in a steel plant, there may be equipment for which a relatively high frequency vibration of, for example, several kHz is detected (see, for example, FIG. 2 described later). When equipment diagnosis is performed at relatively short intervals (for example, intervals of about 10 minutes), high-density information is transmitted in a short time when such high-frequency vibration signals are transmitted to external devices wirelessly. It is necessary to use the highest possible frequency band. For this reason, in a transmission unit that performs radio transmission, there is a possibility that the power consumption increases in order to generate a high frequency (carrier frequency).

  In general, in an iron manufacturing plant, each facility can be dispersed over a wide area. Also, there are many facilities that cannot be approached from the viewpoint of safety. Therefore, the communication distance between the vibration detection device attached to the equipment to be diagnosed and the external device that receives the vibration signal wirelessly transmitted from the vibration detection device also tends to be longer than that of a general factory. . Therefore, a higher wireless output is required for the transmission unit of the vibration detection device, which may increase the power consumption.

  Thus, particularly in an iron manufacturing plant, there is a possibility that the power consumption of the vibration detection device may become larger. Therefore, it is desirable that the vibration detection device is equipped with a power generation mechanism with higher output. However, for example, when a high power generation amount is obtained by a power generation mechanism that generates power by vibrating the movable part as described in Patent Document 2, the influence of the vibration of the movable part on the detection value of the sensor is affected. It becomes larger and it will be more difficult to diagnose highly accurate equipment.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to integrate a sensor that detects vibration and a power generation mechanism that generates power by vibrating a movable part. It is an object of the present invention to provide a novel and improved vibration detection apparatus and vibration detection method capable of detecting vibration with higher accuracy.

  In order to solve the above-described problem, according to an aspect of the present invention, a vibration sensor that detects vibration of equipment and a power generation unit that generates power by vibrating a movable part according to the vibration of the equipment are provided. A vibration detection method for detecting vibration of equipment using a vibration detection device, wherein a frequency analysis process for extracting a frequency component corresponding to vibration of the movable part based on a waveform representing a voltage generated by the power generation part And a filtering process for removing a frequency component corresponding to the extracted vibration of the movable part from the vibration signal representing the vibration of the equipment detected by the vibration sensor. A vibration detection method is provided.

  Further, in the vibration detection method, the vibration detection device includes a power storage unit that stores electric power generated by the power generation unit, a processor that performs the frequency analysis process and the filter process, and a filter unit that performs the filter process. A transmission device that wirelessly transmits a vibration signal from which a frequency component corresponding to vibration has been removed to an external device, wherein the vibration sensor, the processor, and the transmission device are based on electric power supplied from the power storage unit. It may work.

  Moreover, in order to solve the said subject, according to another viewpoint of this invention, the vibration sensor which detects the vibration of an installation, and the electric power generation part which generates electric power by vibrating a movable part according to the vibration of the said installation, Based on the waveform representing the voltage generated by the power generation unit, the frequency analysis unit that extracts the frequency component corresponding to the vibration of the movable unit, and the vibration signal that represents the vibration of the equipment detected by the vibration sensor, And a filter processing unit that removes a frequency component corresponding to the vibration of the movable part extracted by the frequency analysis unit.

  The vibration detection device wirelessly transmits to the external device a power storage unit that stores the electric power generated by the power generation unit, and a vibration signal from which the frequency component corresponding to the vibration of the movable unit has been removed by the filter processing unit. A transmission device, and the vibration sensor, the frequency analysis unit, the filter processing unit, and the transmission device may operate based on electric power supplied from the power storage unit.

  As described above, according to the present invention, in the vibration detection apparatus in which the sensor that detects vibration and the power generation mechanism that generates power by vibrating the movable part are integrated, vibration can be generated with higher accuracy. It becomes possible to detect.

It is the schematic which shows one structural example of the vibration detection apparatus which concerns on this embodiment. It is a graph which shows an example of the detected value of the acceleration sensor of a vibration detection apparatus. It is a block diagram which shows the whole structure of the equipment diagnostic system which concerns on this embodiment. It is a block diagram which shows the example of 1 structure of the vibration detection apparatus which concerns on this embodiment. It is a block diagram which shows one structural example of the equipment diagnosis PC which concerns on this embodiment. It is a flowchart which shows an example of the process sequence of the vibration detection method which concerns on this embodiment. It is a figure which shows the waveform of the vibration signal before and after the filter process acquired by the vibration detection apparatus which concerns on this embodiment. It is a figure which shows the waveform of the vibration signal before and after the filter process acquired by the vibration detection apparatus which concerns on this embodiment.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

(1. Configuration of vibration detection device)
With reference to FIG. 1, the structure of the vibration detection apparatus which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a schematic diagram illustrating a configuration example of a vibration detection device according to the present embodiment.

  Referring to FIG. 1, the vibration detection device 60 according to the present embodiment is configured by mounting an acceleration sensor 620 and a power generation unit 630 in a housing 610. In FIG. 1, internal components are illustrated through the housing 610 for explanation. As shown in FIG. 1, the vibration detection device 60 is mounted and fixed on the surface (installation surface) of the equipment 700 to be diagnosed, and the acceleration sensor 620 can detect the vibration of the equipment 700. In the figure, an arrow on the installation surface of the facility 700 schematically indicates the main vibration direction of the facility 700.

  In the following description, for the sake of simplicity, it is assumed that the installation surface of the facility 700 is a substantially uniform plane, and two directions orthogonal to each other in the plane are defined as an x-axis direction and a y-axis direction. A direction perpendicular to the installation surface of the facility 700 is defined as a z-axis direction.

The acceleration sensor 620 is an example of a vibration sensor that detects vibration. The acceleration sensor 620 is a uniaxial acceleration sensor, for example, and is arranged so that its detection axis is perpendicular to the installation surface of the facility 700. The acceleration sensor 620 can detect a vibration signal representing the vibration of the facility 700 as acceleration (m / sec ² ) in the detection axis direction. However, the acceleration sensor 620 is not limited to this example, and may be a biaxial or triaxial acceleration sensor, for example. Further, the type of the acceleration sensor 620 is not uniquely limited, and various types of devices such as a capacitance type and a piezoresistive type may be applied as the acceleration sensor 620. Furthermore, instead of the acceleration sensor 620, a vibration sensor that detects vibration based on another physical quantity (for example, displacement or speed) may be used.

  The acceleration sensor 620 is disposed on the installation surface of the facility 700 through the partition wall of the housing 610. By disposing the acceleration sensor 620 on the installation surface of the facility 700, it is possible to suitably detect vibration with low directivity and high frequency vibration in the facility 700. Note that a partition wall may not be provided on a contact surface of the housing 610 with the facility 700, and the acceleration sensor 620 may be disposed so as to directly contact the facility 700. By directly bringing the acceleration sensor 620 into contact with the facility 700, vibrations with low directivity and high-frequency vibrations in the facility 700 described above can be detected with higher accuracy.

  The power generation unit 630 includes a coil 640, a weight 650, a spring 655, and a permanent magnet 670 mounted in a housing 680. The housing 680 and the housing 610 are connected to each other by a connecting member (not shown) such as a bolt, for example, and the power generation unit 630 is fixedly connected to the housing 610. In the example illustrated in FIG. 1, the housing 680 has a cylindrical shape, but the shape of the housing 680 is not limited to this example, and may be another shape.

  One end of the spring 655 is connected to one surface (upper surface) of the housing 680 and the weight 650 is connected to the other end. A coil 640 is wound around the weight 650 with a predetermined number of turns. Thus, the spring 655 is configured to be extendable in the extending direction in a state where the movable portion 660 including the weight 650 and the coil 640 is provided at the tip. Further, the permanent magnet 670 is disposed so as to face the movable portion 660 in the expansion / contraction direction of the spring 655.

  In the example shown in FIG. 1, vibration detection is performed so that the expansion / contraction direction of the spring 655 is substantially perpendicular to the installation surface of the facility 700 (that is, the expansion / contraction direction of the spring 655 is substantially parallel to the z-axis direction). A device 60 is installed. When the facility 700 vibrates, the movable part 660 composed of the weight 650 and the coil 640 vibrates in the z-axis direction, and the spring 655 expands and contracts in the z-axis direction. Due to the expansion and contraction of the spring 655, the magnetic field applied to the coil 640 by the permanent magnet 670 changes, and an induced current is generated in the coil 640. As described above, in the power generation unit 630, the coil 640 and the weight 650 (that is, the movable unit 660) vibrate according to the vibration of the facility 700, thereby generating electric power.

  In the present embodiment, the power generation unit 630 only needs to have a function of generating power based on the vibration of the movable unit 660, and the specific configuration is not limited to the example illustrated in FIG. For example, the power generation unit 630 may have a beam-shaped movable unit as described in Patent Document 2 and generate power based on vibration of the beam. In addition, the power generation unit 630 may be configured such that the movable part is configured by a magnet, and power is generated by the magnet vibrating in the coil.

  The coil 640 and the acceleration sensor 620 are electrically connected by, for example, a conductive wire (schematically shown in the drawing), and the acceleration sensor 620 can be driven by the electric power generated in the power generation unit 630. . Although not shown in FIG. 1 for simplicity, the vibration detection device 60 stores a rectifier that converts an alternating current generated in the power generation unit 630 into a direct current or power generated by the power generation unit 630. You may further provide an electrical storage part (battery etc.). The electric power generated by the power generation unit 630 may be supplied to the acceleration sensor 620 after being temporarily stored in the power storage unit via the processing circuit such as the rectifier. The functions of these rectifiers and power storage units will be described in detail below (2. Configuration of equipment diagnosis system).

  Furthermore, in this embodiment, the vibration detection device 60 transmits the vibration signal detected by the acceleration sensor 620 to an external device (for example, a facility diagnosis PC (Personal Computer) that performs various signal processing for facility diagnosis). The transmission device, the acceleration sensor 620, and a microcomputer that controls driving of the transmission device are further provided (both the transmission device and the microcomputer are not shown in FIG. 1). Since the transmission device is provided, it is not necessary to transmit vibration data to an external device by wired communication, so that a situation in which smooth operation of the facility 700 is hindered by a data transmission cable is prevented. In addition, it is possible to solve other problems that may occur due to the provision of a data transmission cable, that is, various problems such as cable disconnection due to vibration of the facility 700 and an increase in cost associated with cable laying. Become. Further, the acceleration detection frequency (that is, the sampling rate) by the acceleration sensor 620, the vibration data transmission frequency to the external device of the transmission device, and the like are appropriately controlled by the processor mounted on the microcomputer. The functions of these transmitters and microcomputers will also be described in detail in the following (2. Equipment configuration system configuration).

  Here, in order to increase the power generation amount in the power generation unit 630, it is preferable that the main vibration direction of the facility 700 and the vibration direction of the movable unit 660 are substantially parallel. For example, as shown in FIG. 1, when the main vibration direction of the facility 700 is substantially parallel to the z-axis direction, the vibration direction of the movable portion 660 of the power generation unit 630 of the vibration detection device 60 is also substantially parallel to the z-axis. Therefore, the movable part 660 vibrates with a larger acceleration, and the power generation amount also increases. Therefore, it is possible to generate power for driving the vibration detection device 60 more efficiently.

  However, when the vibration acceleration of the movable part 660 increases, the influence of the vibration of the movable part 660 on the detection value of the acceleration sensor 620 increases, and there is a concern that minute vibrations in the facility 700 may not be detected with high accuracy. Since some of the diagnostic items of the facility 700 determine that the facility 700 is abnormal based on such minute vibrations, the vibration component of the movable portion 660 becomes noise in the detection value of the acceleration sensor 620. there is a possibility.

  As an example, FIG. 2 shows the detection value of the acceleration sensor 620 when the vibration detection device 60 is attached to the bearing of the speed reducer output shaft of the transport roll in the steel plant. FIG. 2 is a graph illustrating an example of a detection value of the acceleration sensor 620 of the vibration detection device 60. In FIG. 2, the horizontal axis represents time, the vertical axis represents vibration acceleration, which is the output value of the acceleration sensor 620, and the relationship between the two is plotted.

  Referring to FIG. 2, it can be seen that a long wavelength (low frequency) sine wave is detected and a short wavelength (high frequency) waveform is superimposed on the sine wave. The low-frequency waveform mainly represents a vibration component by the movable part 660 of the power generation part 630, for example, the vibration of the movable part 660. On the other hand, the high-frequency waveform represents high-frequency vibration that can occur in the facility 700. In the diagnosis of the facility 700, there is a case in which an abnormality is determined based on such high-frequency vibration. Therefore, when performing the diagnosis of the facility 700, the vibration component of the movable unit 660 can be noise. Therefore, when the vibration acceleration of the movable portion 660 increases, the detection value of the acceleration sensor 620 becomes more dominant in the low-frequency waveform that can be noise during diagnosis, and the detection accuracy of the high-frequency vibration signal that is originally desired to be observed may be reduced. There is.

  Therefore, in the present embodiment, a frequency component corresponding to the vibration of the movable unit 660 is extracted from a waveform (for example, a current waveform of an induced current) representing a voltage generated by the power generation unit 630, and is a detection value of the acceleration sensor 620. A filtering process (filtering process) is performed to remove a frequency component corresponding to the extracted vibration of the movable part 660 from the waveform of the vibration signal indicating the vibration of the facility 700. By performing such a filtering process, a waveform that can be a noise when the equipment 700 is diagnosed is removed, and vibrations of the equipment 700 can be detected with higher accuracy. Therefore, the equipment 700 can be diagnosed more accurately. It becomes possible. Below, the structure of the equipment diagnosis system which concerns on this embodiment which implement | achieves the highly accurate diagnosis of the equipment 700 based on the said filter process is demonstrated.

(2. Configuration of equipment diagnosis system)
(2-1. Overall configuration of equipment diagnosis system)
With reference to FIG. 3, the outline | summary of the equipment diagnostic system which concerns on this embodiment is demonstrated. FIG. 3 is a block diagram showing the overall configuration of the equipment diagnosis system according to the present embodiment.

  Referring to FIG. 3, the facility diagnosis system 1 according to the present embodiment includes a vibration detection device 20 and a facility diagnosis PC 30. Note that, in FIG. 3, only the main components of the configuration of the vibration detection device 20 and the facility diagnosis PC 30 are illustrated in order to explain the outline of the facility diagnosis system 1. More specific configurations of the vibration detection device 20 and the equipment diagnosis PC 30 will be described in detail below (2-2. Configuration of the vibration detection device) and below (2-3. Configuration of the equipment diagnosis PC).

  The vibration detection device 20 corresponds to the vibration detection device 60 shown in FIG. The vibration detection device 20 is attached to a facility (not shown) that is a diagnosis target, detects a vibration signal that represents the vibration of the facility, and performs a filtering process as described above on the detected vibration signal. Signal processing. The vibration detection device 20 and the facility diagnosis PC 30 are configured to be communicable wirelessly, and a vibration signal subjected to various signal processing including filter processing (hereinafter also referred to as a filtered vibration signal). And transmitted from the vibration detection device 20 to the equipment diagnosis PC 30. The equipment diagnosis PC 30 diagnoses equipment by performing various types of analysis such as frequency analysis on the received vibration signal after filtering.

  A schematic configuration of the vibration detection device 20 and the facility diagnosis PC 30 will be described. The vibration detection device 20 includes a vibration signal detection unit 201, an amplifier 203, a filter processing unit 205, a power generation unit 207, a rectifier 209, a power storage unit 211, a frequency analysis unit 213, and a wireless transmission unit 215.

  The vibration signal detection unit 201 corresponds to the acceleration sensor 620 shown in FIG. 1 and detects a vibration signal representing the vibration of the equipment to be diagnosed. The vibration signal detected by the vibration signal detection unit 201 is appropriately amplified by the amplifier 203 and provided to the subsequent filter processing unit 205. In the filter processing unit 205, the above-described filter processing is performed to remove the frequency component corresponding to the vibration of the movable unit 660 shown in FIG. 1 from the waveform of the vibration signal.

  FIG. 3 schematically illustrates an example of the vibration signal detected by the vibration signal detection unit 201, the vibration signal amplified by the amplifier 203, and the waveform of the vibration signal subjected to the filter processing by the filter processing unit 205. ing. As shown in these waveforms, the vibration signal detected by the vibration signal detector 201 has a waveform in which a relatively high frequency waveform is superimposed on a relatively low frequency sine wave-like waveform. By performing the filtering process by the filter processing unit 205, the low frequency waveform is removed and the high frequency waveform is extracted.

  The power generation unit 207 corresponds to the power generation unit 630 illustrated in FIG. 1 and generates power by the vibration of the movable unit 660 according to the vibration of the facility. For example, in the power generation unit 207, an induced current is generated in the coil 640 by the vibration of the movable unit 660 shown in FIG. The waveform of the induced current (that is, the waveform representing the voltage generated by the power generation unit 207) can be a waveform having a period corresponding to the vibration of the movable unit 660, as schematically shown in FIG.

  The induced current generated in the power generation unit 207 is converted from an alternating current to a direct current by the rectifier 209 and stored in the power storage unit 211 made of, for example, a battery. The power stored in the power storage unit 211 is supplied to each unit of the vibration detection device 20, so that the vibration detection device 20 is driven.

  The induced current generated in the power generation unit 207 is also provided to the frequency analysis unit 213. Since the induced current is generated based on the vibration of the movable portion 660 of the power generation unit 207, the waveform of the induced current includes a waveform representing the vibration of the movable portion 660. The frequency analysis unit 213 extracts a frequency component corresponding to the vibration of the movable unit 660 of the power generation unit 207 based on the waveform of the induced current. Information about the extracted frequency component corresponding to the vibration of the movable unit 660 is provided to the filter processing unit 205, and the filter processing unit 205 performs filtering using the information about the frequency component corresponding to the vibration.

  The vibration signal filtered by the filter processing unit 205 is transmitted to the equipment diagnosis PC 30 by the wireless transmission unit 215. The wireless transmission unit 215 is configured by a communication device that can transmit various types of information using a predetermined communication method.

  The facility diagnosis PC 30 performs facility diagnosis based on the vibration signal detected by the vibration detection device 20 and subjected to the filter processing. The equipment diagnosis PC 30 includes a wireless reception unit 301 and a diagnosis unit 303.

  The wireless reception unit 301 is configured by a communication device that can receive various types of information using a predetermined communication method. The wireless reception unit 301 has the same communication method as the wireless transmission unit 215 of the vibration detection device 20 and is configured by a communication device that can receive various types of information transmitted from the wireless transmission unit 215. The wireless reception unit 301 provides the received filtered vibration signal to the diagnosis unit 303.

  The diagnosis unit 303 diagnoses the equipment based on the vibration signal after the filter processing. For example, the diagnosis unit 303 can diagnose the facility by performing various processes such as an envelope process and a frequency analysis process on the vibration signal according to the diagnosis item.

  The overview of the equipment diagnosis system 1 according to the present embodiment has been described above with reference to FIG. Next, the configuration of the vibration detection device 20 and the facility diagnosis PC 30 that configure the facility diagnosis system 1 will be described in more detail.

(2-2. Configuration of vibration detection device)
With reference to FIG. 4, the structure of the vibration detection apparatus 20 is demonstrated in detail. FIG. 4 is a block diagram illustrating a configuration example of the vibration detection apparatus 20 according to the present embodiment. FIG. 4 illustrates the configuration of the vibration detection apparatus 20 illustrated in FIG. 3 in more detail. In FIG. 4, the flow of current is represented by broken arrows, and the flow of signals and information is represented by solid arrows.

  Referring to FIG. 4, the vibration detection device 20 includes an acceleration sensor 620, an amplifier 203, a filter processing unit 205, a power generation unit 207, a rectifier 209, a power storage unit 211, a frequency analysis unit 213, a wireless transmission unit 215, and an A / D converter. 217, a vibration signal control unit 219, a vibration signal storage unit 221, a power storage control unit 223, an insulation amplifier 225, a post-processing signal control unit 227, and a post-processing signal storage unit 229. In the example illustrated in FIG. 4, among these configurations, the amplifier 203, the filter processing unit 205, the frequency analysis unit 213, the A / D converter 217, the vibration signal control unit 219, the vibration signal accumulation unit 221, and the post-processing signal control unit 227 and the post-processing signal storage unit 229 may be integrated into the microcomputer 231. The wireless transmission unit 215 can be implemented as one function of the transmission device 233 that is a device different from the microcomputer 231. However, the apparatus configuration shown in FIG. 1 is an example, and the present embodiment is not limited to such an example. The vibration detection device 20 only needs to be configured so that each process described below can be executed, and the specific configuration thereof may be arbitrary.

  The vibration detection device 20 is mounted on the facility 700 so that the acceleration sensor 620 is placed on the surface of the facility 700. The acceleration sensor 620 corresponds to the vibration signal detection unit 201 illustrated in FIG. 3 and detects a vibration signal representing the vibration of the equipment 700 that is a diagnosis target as an acceleration value. The vibration signal detected by the acceleration sensor 620 is provided to the amplifier 203.

  The amplifier 203 includes a signal amplification circuit such as an amplifier, and amplifies the vibration signal detected by the acceleration sensor 620 at a predetermined magnification. In the present embodiment, the specific configuration of the amplifier 203 is not limited, and various known amplifiers that are generally used in electric circuits can be applied as the amplifier 203. The amplification performance of the amplifier 203 may be appropriately designed according to the performance of the acceleration sensor 620, the diagnosis item of the facility 700, and the like. The vibration signal amplified by the amplifier 203 is provided to the A / D converter 217.

  The A / D converter 217 converts the vibration signal amplified by the amplifier 203 into a digital signal. In the present embodiment, the specific configuration of the A / D converter 217 is not limited. As the A / D converter 217, various known A / D converters that are generally used in electric circuits are used. Can be applied. The vibration signal converted into a digital signal by the A / D converter 217 is provided to the vibration signal control unit 219.

  The vibration signal control unit 219 is configured by a processor such as a CPU (Central Processing Unit), for example, and controls various processes related to the vibration signal before the filter process is performed. For example, the vibration signal control unit 219 controls driving of the acceleration sensor 620 and controls the sampling rate and detection time (sampling time) of the vibration signal by the acceleration sensor 620. The vibration signal control unit 219 controls driving of the vibration signal storage unit 221 and the filter processing unit 205, and stores the vibration signal converted into a digital signal by the A / D converter 217 in the vibration signal storage unit 221. The filter processing unit 205 performs processing.

  The vibration signal accumulation unit 221 is configured by a storage device that stores various types of information, and temporarily stores the vibration signal converted into a digital signal by the A / D converter 217 under the control of the vibration signal control unit 219. . The data storage method in the vibration signal storage unit 221 may be arbitrary, and the vibration signal storage unit 221 is, for example, a magnetic storage device such as an HDD (Hard Disk Drive), a semiconductor storage device, an optical storage device, or a magneto-optical storage. It can be constituted by various known storage devices such as devices. The vibration signal temporarily stored in the vibration signal storage unit 221 is transmitted to the subsequent filter processing unit 205 at an appropriate timing under the control of the vibration signal control unit 219, and the filter processing unit 205 performs filter processing on the vibration signal. Executed.

  The power generation unit 207 corresponds to the power generation unit 630 illustrated in FIG. 1, and generates power by vibrating the movable unit 660 according to the vibration of the facility 700 to which the vibration detection device 20 is attached. Specifically, in the power generation unit 207, an induced current is generated in the coil 640 by the vibration of the movable unit 660 shown in FIG. The induced current is an alternating current having a period (frequency) corresponding to the vibration of the movable part 660. The induced current generated in the coil 640 of the power generation unit 207 is provided to the rectifier 209 and the insulation amplifier 225.

  The rectifier 209 converts the induced current generated in the power generation unit 207 from an alternating current to a direct current. In the present embodiment, the specific configuration of the rectifier 209 is not limited, and various known rectifiers that are generally used in an electric circuit can be applied as the rectifier 209. The induced current converted into a direct current by the rectifier 209 is provided to the power storage control unit 223.

  The power storage control unit 223 is configured by a processor such as a CPU, for example, and adjusts the amount of current supplied to the power storage unit 211 according to the state of the power storage unit 211 (for example, the amount of power storage). For example, the power storage control unit 223 monitors the power storage amount in the power storage unit 211, and the power generation unit 207 generates the power storage unit 211 when the power storage amount of the power storage unit 211 becomes smaller than a predetermined threshold value. Supply current. By controlling the amount of current supplied to the power storage unit 211 by the power storage control unit 223, overcharge in the power storage unit 211 is prevented.

  The power storage unit 211 is configured by a battery, for example, and stores power generated by the power generation unit 207. The power storage unit 211 supplies power to each component of the vibration detection device 20 such as the acceleration sensor 620, the microcomputer 231, and the transmission device 233. In this way, the vibration detection device 20 can drive itself with the power generated by the power generation unit 207. Note that a specific configuration of the power storage unit 211 is not limited, and various known secondary batteries may be used as the power storage unit 211.

  The insulation amplifier 225 limits the voltage value of the induced current generated by the power generation unit 207 to a predetermined value or less. As the insulation amplifier 225, a voltage drop element such as a resistor may be used, or a filter circuit that allows only a current having a voltage value equal to or lower than a predetermined threshold may be used. The induced current that has passed through the insulation amplifier 225 is transmitted to the frequency analysis unit 213 of the microcomputer 231. In general, since the drive current of the microcomputer 231 is often about several (mA), an excessive voltage is applied to the microcomputer 231 by transmitting the induced current to the microcomputer 231 via the insulation amplifier 225. It is prevented.

  The frequency analysis unit 213 is configured by a processor such as a CPU, for example, performs frequency analysis on the waveform of the induced current generated by the power generation unit 207, and extracts a frequency component corresponding to the vibration of the movable unit 660 of the power generation unit 207. . The frequency analysis unit 213 is provided with an induced current before being converted into a direct current by the rectifier 209. Since the waveform of the induced current includes a waveform representing the vibration of the movable portion 660 of the power generation unit 207, the frequency analysis is performed by the frequency analysis unit 213, so that the frequency component corresponding to the vibration of the movable portion 660 is obtained. Can be extracted. For example, the frequency analysis unit 213 extracts a frequency component corresponding to the primary vibration of the movable unit 660 from the waveform of the induced current. Various known techniques may be used for frequency analysis by the frequency analysis unit 213. The frequency analysis unit 213 provides the filter processing unit 205 with information about the frequency component corresponding to the extracted vibration of the movable unit 660.

  The filter processing unit 205 is configured by a processor such as a CPU, for example, and a frequency component corresponding to the vibration of the movable unit 660 of the power generation unit 207 from the vibration signal detected by the acceleration sensor 620 under the control of the vibration signal control unit 219. A filtering process is performed to remove. Specifically, the vibration signal stored in the vibration signal storage unit 221 is provided from the vibration signal control unit 219 to the filter processing unit 205. Further, the filter processing unit 205 is provided with information about frequency components corresponding to the vibration (for example, primary vibration) of the movable unit 660 extracted by the frequency analysis unit 213. Therefore, the filter processing unit 205 corresponds to the vibration of the movable unit 660 that may cause noise, for example, by causing an inverse bandpass filter that removes only the waveform of the frequency band corresponding to the primary vibration of the movable unit 660 to act on the vibration signal. The frequency component can be removed. The driving of the filter processing unit 205 may be controlled by the vibration signal control unit 219. The vibration signal control unit 219 may be, for example, a frequency analysis unit 213 for an induced current generated in the power generation unit 207 while the vibration signal is acquired. The filter processing unit 205 can perform filter processing on the vibration signal at the timing when the frequency analysis processing by is completed. The filter processing unit 205 provides the processed vibration signal to the post-processing signal control unit 227.

  The post-processing signal control unit 227 is configured by a processor such as a CPU, for example, and controls various processes related to the vibration signal after the filtering process is performed. For example, the post-processing signal control unit 227 controls the driving of the post-processing signal accumulation unit 229 and the wireless transmission unit 215, and stores the filtered vibration signal in the post-processing signal storage unit 229 or the wireless transmission unit 215. It is transmitted to the equipment diagnosis PC 30 which is an external device.

  The post-processing signal accumulation unit 229 is configured by a storage device that stores various types of information, and temporarily stores the vibration signal subjected to the filter processing by the filter processing unit 205 under the control of the post-processing signal control unit 227. . The storage method of data in the post-processing signal storage unit 229 may be arbitrary, and the post-processing signal storage unit 229 includes, for example, a magnetic storage unit device such as an HDD, a semiconductor storage device, an optical storage device, a magneto-optical storage device, etc. It can be constituted by various known storage devices. The vibration signal temporarily stored in the post-processing signal accumulation unit 229 can be provided to the subsequent wireless transmission unit 215 at an appropriate timing under the control of the post-processing signal control unit 227.

  The wireless transmission unit 215 is configured by a communication device capable of transmitting various types of information by a predetermined communication method. Under the control from the post-processing signal control unit 227, the filtered vibration signal is transmitted to the equipment diagnosis PC 30 that is an external device. Send. For example, the wireless transmission unit 215 may transmit the vibration signal after filter processing using radio waves in a predetermined frequency band. However, the communication method of the wireless transmission unit 215 is not limited to such an example, and the wireless transmission unit 215 may perform wireless communication using electromagnetic waves in a frequency band other than radio waves such as ultrasonic waves and infrared rays. The timing at which the wireless transmission unit 215 transmits the filtered vibration signal may be appropriately determined according to the type of equipment 700, diagnostic items, and the like. For example, if it is desired to make a diagnosis based on vibration signals acquired over a long period of time such as several days, vibration data for several days is temporarily stored in the post-processing signal storage unit 229. The vibration data may be transmitted to the equipment diagnosis PC 30 by the wireless transmission unit 215 at the timing of performing the diagnosis.

  The configuration of the vibration detection device 20 has been described above with reference to FIG.

(2-3. Configuration of equipment diagnosis PC)
With reference to FIG. 5, the configuration of the facility diagnosis PC 30 will be described in more detail. FIG. 5 is a block diagram illustrating a configuration example of the equipment diagnosis PC 30 according to the present embodiment. FIG. 5 illustrates the configuration of the facility diagnosis PC 30 illustrated in FIG. 3 in more detail.

  Referring to FIG. 5, the facility diagnosis PC 30 includes a wireless reception unit 301 and a diagnosis unit 303. The wireless reception unit 301 is configured by a communication device that can receive various types of information using a predetermined communication method, and receives the filtered vibration signal transmitted from the wireless transmission unit 215 of the vibration detection device 20. As a communication method of the wireless reception unit 301, for example, the same communication method as that of the wireless transmission unit 215 can be set as appropriate so as to be able to communicate with the wireless transmission unit 215 of the vibration detection device 20. The wireless reception unit 301 provides the received filtered vibration signal to the diagnosis unit 303.

  The diagnosis unit 303 is configured by a processor such as a CPU, for example, and diagnoses the facility 700 based on the vibration signal after the filter process. The diagnosis unit 303 can diagnose the facility 700 by performing various known processes related to vibration analysis such as envelope processing and frequency analysis processing on the vibration signal after the filter processing. For example, the diagnosis unit 303 may analyze the characteristics of the vibration signal in the middle-range and high-range frequency bands from the result of frequency analysis according to the diagnosis item. In addition, a history of vibration signals acquired for each facility 700 may be stored in a storage unit (not shown) included in the facility diagnosis PC 30, and the diagnosis unit 303 stores vibration signals stored in the storage unit. The tendency of the vibration signal acquired during operation may be managed on the basis of the history.

  In the above, with reference to FIGS. 3-5, the vibration detection apparatus 20 and equipment diagnosis PC30 which comprise the equipment diagnosis system 1 were demonstrated in detail. As described above, the vibration detection device 20 according to the present embodiment includes the acceleration sensor 620 that detects a vibration signal according to the vibration of the facility, and the power generation unit that generates power by the vibration of the movable unit 660 according to the vibration of the facility. 207, and the detected vibration signal is subjected to filter processing for removing a frequency component corresponding to the vibration of the movable unit 660 extracted from the waveform representing the voltage generated by the power generation unit 207. Then, on the basis of the vibration signal after the filtering process, the facility diagnosis PC 30 performs a diagnosis process on the facility 700. When the equipment is diagnosed using the vibration signal, the vibration component of the movable portion 660 can become noise. Therefore, the above-described filter processing removes the component that can be noise, so that the vibration with higher accuracy can be obtained. A signal can be obtained and more accurate diagnosis of the facility 700 is realized. In particular, when a high power generation amount is required in the power generation unit 207 and there is a possibility that the vibration acceleration of the movable unit 660 of the power generation unit 207 may increase, as in an iron manufacturing plant, for example, the vibration detection device 20 according to the present embodiment. Can be suitably applied. According to this embodiment, even when the power generation amount in the power generation unit 207 is large and the vibration acceleration of the movable unit 660 is large, the influence of the vibration component of the movable unit 660 can be effectively removed from the vibration signal. It becomes possible.

  Further, in the present embodiment, the vibration detection device 20 includes a microcomputer 231 that controls driving of the vibration detection device 20 and a transmission device 233 that wirelessly transmits a vibration signal to the equipment diagnosis PC 30. The Accordingly, the vibration detection device 20 automatically performs various processes such as detection of vibration signals, filter processing for the detected vibration signals, and transmission of the vibration signals after the filter processing to the equipment diagnosis PC 30 according to a predetermined program. Is called. Moreover, since the vibration detection apparatus 20 is driven by the electric power generated by the power generation unit 207, frequent replacement work such as a battery as a power storage unit is not necessary. Therefore, after attaching the vibration detection device 20 to the facility 700, the operator can diagnose the facility 700 based on the vibration signal transmitted from time to time to the facility diagnosis PC 30, so that the diagnosis work can be performed more efficiently. Can be done.

  In the configuration of the equipment diagnosis system 1 described above, the filter processing unit 205, the frequency analysis unit 213, the vibration signal control unit 219, the power storage control unit 223, the post-processing signal control unit 227, and the diagnosis unit 303 include a CPU or the like. It may be a function realized by the processor. These functions can be realized by the processor operating according to a predetermined program. Moreover, it is possible to produce a computer program for realizing each function of the facility diagnosis system 1 according to the present embodiment, and to implement it in various information processing apparatuses. In addition, a computer-readable recording medium storing such a computer program can be provided. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, or the like. Further, the above computer program may be distributed via a network, for example, without using a recording medium.

  In the example illustrated in FIG. 3, the equipment diagnosis system 1 is configured by the vibration detection device 20 and the equipment diagnosis PC 30, but the present embodiment is not limited to such an example. The facility diagnosis system 1 only needs to be configured to realize the functions described above, and the specific configuration thereof may be arbitrary. For example, the frequency analysis processing by the frequency analysis unit 213 and the filter processing by the filter processing unit 205 may not be performed by the vibration detection device 20, and may be performed by the equipment diagnosis PC 30 (or other various information processing devices). Good. In this case, the vibration detection device 20 transmits the vibration signal detected by the acceleration sensor 620 and a signal representing the waveform of the voltage generated by the power generation unit 207 to the equipment diagnosis PC 30, and subsequent processing is performed by the equipment diagnosis PC 30. Can be broken. By reducing the processing performed by the vibration detection device 20, the power consumption of the vibration detection device 20 can be reduced. Further, for example, by performing frequency analysis processing and filter processing in an information processing device such as a server specialized in numerical computation, it becomes possible to perform these signal processing in a shorter time, thereby improving work efficiency. it can.

(3. Vibration detection method)
With reference to FIG. 6, the processing procedure of the vibration detection method according to the present embodiment will be described. FIG. 6 is a flowchart illustrating an example of a processing procedure of the vibration detection method according to the present embodiment. Each process shown in FIG. 6 can be executed by each component of the equipment diagnosis system 1 shown in FIGS.

  Referring to FIG. 6, in the vibration detection method according to the present embodiment, first, a vibration signal representing the vibration of the facility 700 is detected by the acceleration sensor 620 of the vibration detection device 20 attached to the facility 700 to be diagnosed ( Step S101). The detected vibration signal is amplified by the amplifier 203 and converted into a digital signal by the A / D converter 217 (step S103).

  On the other hand, a frequency component corresponding to the primary vibration representing the vibration of the movable portion 660 of the power generation unit 207 is extracted from the induced current (alternating current) generated in the power generation unit 207 of the vibration detection device 20 (step S105). The process shown in step S105 can be performed by, for example, the frequency analysis unit 213 shown in FIGS. In FIG. 6, for convenience, it is described that the process shown in step S105 is performed after the process shown in steps S101 and S103. However, the process shown in steps S101 and S103 and the process shown in step S105 are described. May be performed in parallel.

  Next, a filtering process is performed to remove a frequency component corresponding to the vibration of the movable unit 660 of the power generation unit 207 from the detected vibration signal (step S107). Specifically, in step S107, the reverse of passing the signal of the frequency other than the frequency band corresponding to the primary vibration acquired in the process shown in step S105 with respect to the vibration signal acquired in the process shown in step S103. Band pass filter processing is performed. The process shown in step S107 can be performed by, for example, the filter processing unit 205 shown in FIGS. In FIG. 6, as an example, the frequency component corresponding to the primary vibration is extracted in step S105, and the filtering process based on the frequency component corresponding to the primary vibration is performed in step S107. In step S105, The frequency component corresponding to the vibration of the other order mode may be extracted, and in step S107, the filtering process using the frequency component corresponding to the extracted vibration of the other order mode may be performed.

  Next, the vibration signal after the filter processing is transmitted from the vibration detection device 20 to the equipment diagnosis PC 30 (step S109). In the process shown in step S109, the vibration signal can be transmitted and received at a predetermined timing by, for example, the wireless transmission unit 215 and the wireless reception unit 301 illustrated in FIGS.

  Subsequent processing corresponds to diagnostic processing performed in the equipment diagnosis PC 30. In the equipment diagnosis PC 30, first, a filter band for extracting only a frequency band to be diagnosed is selected for the received vibration signal after the filter process according to the diagnosis item (step S111). Then, envelope processing is performed on the extracted vibration signal in the frequency band (step S113), and frequency analysis processing is performed (step S115). The processing shown in steps S111 to S115 can be performed by the diagnosis unit 303 shown in FIGS. 3 and 5, for example. In addition, the process shown to step S111-step S115 is an example of the diagnostic process which can be performed by equipment diagnosis PC30 in this embodiment. In the present embodiment, as the diagnosis process, various other known processes that are generally performed when analyzing vibration may be performed.

  The processing procedure of the vibration detection method according to the present embodiment has been described above with reference to FIG. In the vibration detection method according to the present embodiment, after the vibration detection device 20 is attached to the facility 700 in step S103, the processing shown in steps S105 and S107 is performed by, for example, a microprocessor processor provided in the vibration detection device 20, It can be automatically executed according to a predetermined program by the processor of the equipment diagnosis PC. Therefore, after attaching the vibration detection apparatus 20 to the facility 700, the operator can diagnose the facility 700 by referring to the diagnosis result by the facility diagnosis PC 30. Therefore, the diagnosis work of the facility 700 can be performed more efficiently.

  In order to confirm the effect of the present invention, an embodiment in which the present invention is applied to an actual apparatus in an iron manufacturing plant will be described. As an example, the vibration detection device 60 according to the present embodiment was attached to the bearing of the speed reducer output shaft of the transport roll, and vibration signals before and after the filter processing were acquired.

  7 and 8 show the waveforms of the vibration signals obtained before and after the filter processing acquired by the vibration detection device 60 according to the present embodiment. 7 and 8 are diagrams illustrating the waveforms of the vibration signals before and after the filter processing acquired by the vibration detection device 60 according to the present embodiment. In FIGS. 7 and 8, time is plotted on the horizontal axis, vibration acceleration is plotted on the vertical axis, and the relationship between the two is plotted.

  FIG. 7 shows an example of a vibration signal when the bearing is operating in a relatively good state. Referring to FIG. 7, the vibration signal before the filter processing has a waveform in which a high-frequency waveform is superimposed on a low-frequency waveform (sine wave) ((a) in the figure). Note that FIG. 7A shows the same waveform as that shown in FIG. As a result of performing frequency analysis on the current waveform generated in the power generation unit 207 while the vibration signal illustrated in FIG. 7A is acquired by the frequency analysis unit 213 illustrated in FIGS. It was found that the frequency corresponding to the primary frequency of 660 was 11 ± α (Hz) (α was 10 (%)). Therefore, 11 ± α (Hz) (ie, 9.9 (Hz) to 12.1 (Hz) is applied to the vibration signal shown in FIG. 7A by the filter processing unit 205 shown in FIGS. The inverse band pass filter processing which removes the waveform of the frequency band of) was performed. As a result, the low frequency component was removed from the vibration signal, and the waveform of the vibration signal from which only the high frequency component was extracted could be obtained ((b) in the figure). The vibration signal waveform shown in FIG. 7B is obtained by removing the frequency component corresponding to the vibration of the movable portion 660 from the vibration signal detected by the acceleration sensor 620, and may be a noise that can be a noise when diagnosing the bearing. It can be said that the component has been removed. As shown in FIG. 7, by applying the vibration detection device 60 according to the present embodiment, it was confirmed that a component that could be noise was removed, and a vibration signal indicating the state of the equipment was obtained with higher accuracy. .

  On the other hand, FIG. 8 shows an example of a vibration signal when a part of the outer ring rolling surface of the bearing is damaged. Referring to FIG. 8, the vibration signal before the filter processing is dominant in the high frequency component as compared with the waveform shown in FIG. 7, but again the waveform in which the high frequency waveform is superimposed on the low frequency waveform (sine wave). ((A) in the figure). Similarly, with respect to the vibration signal shown in FIG. 8A, the frequency analysis unit 213 similarly performs frequency analysis on the current waveform generated by the power generation unit 630, and as a result, corresponds to the primary frequency of the movable unit 660. It was found that the frequency to perform was 9 ± α (Hz) (α was 10 (%)). Therefore, 9 ± α (Hz) (that is, 8.1 (Hz) to 9.9 (Hz) is applied to the vibration signal illustrated in FIG. 8A by the filter processing unit 205 illustrated in FIGS. 3 and 4. The inverse band pass filter processing which removes the waveform of the frequency band of) was performed.

  FIG. 8B illustrates a waveform of the vibration signal after the filter process is performed on the vibration signal illustrated in FIG. As shown in FIG. 8B, it can be seen that by performing the filter processing according to the present embodiment, the low frequency component is removed from the vibration signal shown in FIG. . The bearing abnormality can be determined with higher accuracy by performing the diagnosis of the bearing using the vibration signal from which the component that can be noise is removed as shown in FIG.

  In the above, the Example which applied this invention to the actual installation was described with reference to FIG.7 and FIG.8.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

1 Equipment diagnosis system 20, 60 Vibration detection device 30 Equipment diagnosis PC
DESCRIPTION OF SYMBOLS 201 Vibration signal detection part 203 Amplifier 205 Filter process part 207 Electric power generation part 209 Rectifier 211 Power storage part 213 Frequency analysis part 215 Wireless transmission part 217 A / D converter 219 Vibration signal control part 221 Vibration signal storage part 223 Power storage control part 225 Insulation amplifier 227 Post-processing signal control unit 229 Post-processing signal accumulation unit 231 Microcomputer 233 Transmitting device 301 Wireless reception unit 303 Diagnosis unit 610, 680 Case 620 Acceleration sensor 630 Power generation unit 640 Coil 650 Weight 655 Spring 660 Movable unit 670 Permanent magnet 700 Equipment

Claims (4)

A vibration detection method for detecting vibration of equipment using a vibration detection device comprising: a vibration sensor that detects vibration of the equipment; and a power generation unit that generates power by vibrating a movable part according to the vibration of the equipment. And
Performing a frequency analysis process for extracting a frequency component corresponding to the vibration of the movable part based on a waveform representing a voltage generated by the power generation part;
Performing a filtering process to remove a frequency component corresponding to the vibration of the movable part extracted from the vibration signal representing the vibration of the equipment detected by the vibration sensor;
A vibration detection method comprising: The vibration detection device includes a power storage unit that stores power generated by the power generation unit, a processor that performs the frequency analysis process and the filter process, and a frequency component corresponding to the vibration of the movable part is removed by the filter process. A transmission device that wirelessly transmits the vibration signal to an external device,
The vibration sensor, the processor, and the transmission device operate based on power supplied from the power storage unit.
The vibration detection method according to claim 1, wherein: A vibration sensor for detecting the vibration of the facility;
A power generation unit that generates power by vibrating the movable part according to the vibration of the facility;
Based on the waveform representing the voltage generated by the power generation unit, a frequency analysis unit that extracts a frequency component corresponding to the vibration of the movable unit,
A filter processing unit for removing a frequency component corresponding to the vibration of the movable part extracted by the frequency analysis unit from a vibration signal representing the vibration of the equipment detected by the vibration sensor;
A vibration detection apparatus comprising: A power storage unit that stores electric power generated by the power generation unit, and a transmission device that wirelessly transmits to the external device a vibration signal from which a frequency component corresponding to vibration of the movable unit has been removed by the filter processing unit,
The vibration sensor, the frequency analysis unit, the filter processing unit, and the transmission device operate based on power supplied from the power storage unit.
The vibration detection device according to claim 3, wherein

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