Vibrator

Abstract

To provide a vibrometer that has excellent portability and reduces troublesomeness of preparation work of measurement.SOLUTION: A vibrometer 1 includes: a case 2 having an internal space 20; a vibration sensor 3 housed in the internal space 20; a pedestal 41 supporting the vibration sensor 3; and a processing unit 7 that is housed in the internal space 20 and performs measurement processing on the basis of detection output outputted from the vibration sensor 3. The vibrometer 1 is mounted on a mounting surface 100. A second through hole 18 is formed at the bottom of the case 2. A second lower end 45a of the pedestal 41 abuts on the mounting surface 100 while passing through the second through hole 18. The pedestal 41 can support the vibration sensor 3 housed in the internal space 20 independently of the case 2.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a vibrometer. [Background technology]

[0002] Vibration meters that measure vibrations have been known for some time. The vibration meter described in Patent Document 1 includes an acceleration sensor as a vibration sensor and a recording device. The acceleration sensor is provided separately from the recording device. The acceleration sensor and the recording device are connected by a cable (wiring). The detection output from the acceleration sensor is provided to the recording device via the cable. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-202961 A Summary of the Invention [Problem to be solved by the invention]

[0004] Vibration measurements are performed at various measurement points. When measuring vibration with a vibration meter, the worker (measurer) needs to carry the vibration meter to the measurement point.

[0005] However, in the above-mentioned vibrometer, the vibration sensor (acceleration sensor) is provided separately from the storage device, so the vibration sensor and the storage device must be carried separately. Therefore, it is not suitable for carrying around. In other words, there is a problem that it lacks portability.

[0006] Furthermore, when vibration measurement is performed, the vibration sensor must be connected to the recording device in preparation for the measurement. That is, each time a vibration measurement is performed, the vibration sensor must be connected via a cable and the cable must be disconnected. This makes the preparation for vibration measurement cumbersome.

[0007] Furthermore, since the cable is routed outside the case, the following problems may occur. That is, if the measurement point is a factory or the like, there is a possibility that noise such as stray current may be received as a signal by running the cable on the ground or floor. Also, since the cable is routed outside the case, there is a possibility that a failure such as cable breakage may occur. Furthermore, when connecting the vibration sensor and the recording device with multiple types of cables, there is a risk that an operator may make a connection mistake.

[0008] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a vibrometer which is highly portable and reduces the hassle of preparation work for measurement. [Means for solving the problem]

[0009] An embodiment of the present invention provides a vibrometer having the following features.

[0010] 1. A vibration meter for measuring vibration, comprising: a case having an internal space; A vibration sensor accommodated in the internal space; a processing unit that is accommodated in the internal space and performs measurement processing based on a detection output output from the vibration sensor.

[0011] According to this configuration, the vibration sensor is accommodated in the internal space, so that the vibration sensor and the processing unit can be carried together, thereby improving the portability of the vibrometer.

[0012] In addition, there is no need to connect the vibration sensor to a case or a processing unit every time a vibration measurement is performed. This simplifies the preparation work for vibration measurement and reduces the hassle of the preparation work. Furthermore, since no cables are routed outside the case, problems caused by this can be avoided.

[0013] Therefore, it is possible to provide a vibrometer that is highly portable and reduces the hassle of preparation work for measurement.

[0014] 2. The vibration meter described in item 1, further comprising a base for supporting the vibration sensor, the base being capable of supporting the vibration sensor housed in the internal space independently from the case.

[0015] If the vibration sensor is housed in the internal space of the case, the following problems arise. That is, if the measurement point is outdoors, the case may vibrate slightly due to the influence of wind, etc. Also, the case may vibrate slightly due to the input of vibrations from other devices housed in the internal space. If these minute vibrations are transmitted to the vibration sensor through the case, the vibration sensor may detect these vibrations as well, which may cause an error in the detection output of the vibration sensor. This may result in a decrease in the accuracy of the vibration measurement.

[0016] According to the above configuration, the base supporting the vibration sensor can support the vibration sensor housed in the internal space independently from the case. When the base supports the vibration sensor independently from the case, not only is the vibration sensor not in contact with the case, but the vibration sensor and the case are not connected to each other. That is, the vibration sensor is physically separated from the case. Therefore, vibration is not transmitted from the case to the vibration sensor. This allows vibration to be measured with high accuracy. Therefore, a vibrometer that is highly portable and can achieve high-accuracy vibration measurement can be provided.

[0017] The base may have legs that contact the placement surface. The base may be capable of being raised and lowered together with the vibration sensor relative to the case and the processing unit. The base may be circular in a plan view. The base may include a plurality of legs. The plurality of legs may be arranged at intervals in a circumferential direction of the base at positions excluding a center of the base in a plan view. 3. The case has a through hole that passes through the bottom wall of the case from top to bottom. Item 3. The vibrometer according to item 2, wherein a lower end of the base is capable of protruding below the case through the through hole.

[0018] According to this configuration, the lower end of the base can abut against the mounting surface through the through hole formed in the bottom wall of the case, thereby enabling a simple configuration to be realized in which the vibration sensor housed in the internal space is supported by the base independently of the case.

[0019] 4. A first engagement portion formed on the case; a second engagement portion formed on the base and engageable with the first engagement portion; 4. The vibrometer according to item 2 or 3, wherein a first distance from a first bottom end of the case to the first engagement portion is shorter than a second distance from a second bottom end of the base to the second engagement portion.

[0020] According to this configuration, a first distance of the first engagement portion from a first lower end of the case is shorter than a second distance of the second engagement portion from a second lower end of the base. Therefore, in a placed state in which the case and the base are placed on the placement surface, the first engagement portion and the second engagement portion do not engage with each other. Therefore, in this placed state, the vibration sensor can be reliably physically separated from the case. Vibration measurement by the vibrometer is performed in the placed state of the vibrometer. Therefore, vibration measurement can be performed using the vibrometer in a state in which the vibration sensor is reliably physically separated from the case 2.

[0021] In addition, when the case of the vibrometer is raised, the vibration sensor and the base may be suspended and supported by the case through engagement between the first and second engagement parts. This allows the vibration sensor, the base and the case to be carried together, further improving the portability of the vibrometer.

[0022] The vibration meter may further include a grip for lifting the case, thereby further improving portability.

[0023] 5. The vibrometer according to item 4, wherein the first engagement portion and the second engagement portion include a first abutment surface and a second abutment surface that abut against each other vertically.

[0024] 6. The vibrometer according to item 5, wherein the first contact surface and the second contact surface are frustum-shaped.

[0025] According to this configuration, since the first and second contact surfaces are frustum-shaped, when the first and second contact surfaces are in contact with each other, the lateral movement of the base relative to the case is restricted. This makes it possible to suppress the movement of the vibration sensor and the base relative to the case when the vibrometer is in a lifted state. Therefore, the vibrometer can be carried while effectively restricting the movement of the vibration sensor and the base relative to the case.

[0026] The vibrometer may include a first engagement portion formed on the case and a second engagement portion formed on the base and engageable with the first engagement portion. The first engagement portion and the second engagement portion may have a case-side abutment surface and a base-side abutment surface that face each other vertically. The base-side abutment surface may be a base-side abutment surface that is formed on the base and tapered downward toward the inside of the base. The case-side abutment surface may be a case-side abutment surface that is formed on the case and tapered to match the base-side abutment surface. When the vibrometer is separated from the mounting surface, the base-side abutment surface and the case-side abutment surface may be in surface contact with each other. When the vibrometer is placed on the mounting surface, the vibration sensor and the base may not be supported by the case. 7. The vibrometer according to any one of items 4 to 6, further comprising a viscous sheet disposed between the vibration sensor and the base.

[0027] Acceleration sensors are sometimes used as vibration sensors. Acceleration sensors are sensitive to shocks. Therefore, it is desirable to minimize the transmission of shocks applied to the case during transportation of the vibration meter to the vibration sensor.

[0028] According to the above configuration, a viscous sheet is disposed between the vibration sensor and the base. The viscous sheet absorbs vibrations. Therefore, even if a large impact is applied to the case, the impact is absorbed by the viscous sheet. This makes it possible to reduce or eliminate the impact transmitted from the case to the vibration sensor. This makes it possible to protect the vibration sensor. Therefore, even if a large impact is applied to the case, the impact can be suppressed or prevented from being transmitted to the vibration sensor.

[0029] 8. The vibrometer according to any one of items 1 to 7, wherein the vibration sensor is a sensor for measuring minute vibrations (micro-movement acceleration).

[0030] Vibration meters for measuring minute vibrations are used at various measurement points, so they need to be highly portable.

[0031] According to the above configuration, the vibration sensor for measuring minute vibrations is housed in the internal space. Therefore, the vibration sensor and the processing unit can be carried together. This improves the portability of the vibrometer for measuring minute vibrations.

[0032] 9. The vibrometer according to any one of items 2 to 7, further comprising a protective cover that covers a bottom portion of the case and can be coupled to the base in a screw-fastened manner.

[0033] According to this configuration, the bottom of the case is covered with the protective cover, which makes it possible to protect the bottom of the case 2 and suppress or prevent the transmission of shock to the vibration sensor.

[0034] In addition, by fastening the protective cover to the base with screws, the base can be pressed against the case by the screwing, and the base can be positioned in the case. This makes it possible to suppress or prevent the vibration sensor from wobbling in the internal space. Therefore, the vibration meter can be easily transported. [Brief description of the drawings]

[0035] [Figure 1] 1 is a schematic cross-sectional view of a main part of a vibrometer according to a first embodiment of the present invention. [Diagram 2] 2 is a schematic cross-sectional view taken along the line II-II in FIG. 1. [Diagram 3] 3 is a cross-sectional view of the vibrometer in a lifted state, and corresponds to FIG. 2; FIG. [Figure 4] FIG. 2 is a schematic perspective view of the vibrometer with its cover open; [Diagram 5] 5 is a schematic perspective view of the vibrometer, showing a state in which a processing unit is removed from the state shown in FIG. 4. [Figure 6] 6 is a schematic perspective view of the vibrometer, showing a state where a sensor housing unit is removed from FIG. 5; FIG. [Figure 7] FIG. 2 is a perspective view of the sensor housing unit. [Figure 8] FIG. 2 is a block diagram showing an electrical configuration of the vibrometer. [Figure 9] 4 is a flowchart showing a flow of a vibration measurement process using the vibrometer. [Figure 10] FIG. [Figure 11] 5 is a schematic cross-sectional view of a main part of a vibrometer according to a second embodiment of the present invention, the view corresponding to FIG. 2. FIG. [Figure 12] 1 is a graph illustrating the characteristics of a viscous sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0037] Fig. 1 is a schematic cross-sectional view of a main part of a vibrometer 1 according to a first embodiment of the present invention. Fig. 2 is a schematic cross-sectional view taken along the cutting line II-II in Fig. 1. Fig. 3 is a cross-sectional view of the vibrometer 1 in a state where the vibrometer 1 is lifted up, and corresponds to Fig. 2. Figs. 4 to 6 are perspective views of the vibrometer 1. Fig. 7 is a perspective view of a sensor housing unit 8.

[0038] 1 coincides with the left-right direction X of the vibrometer 1, the direction substantially perpendicular to the plane of ...

[0039] 1 to 3, the vibrometer 1 is placed at a predetermined measurement point and used to measure vibrations at the measurement point. Specifically, the vibrometer 1 may be used to measure at least one of microtremors and earthquake motions at the measurement point. The vibrometer 1 is placed on a support surface 100 (see FIGS. 1 to 3) such as the ground, a floor, a desk, etc. at the measurement point and measures vibrations of the support surface 100 (i.e., the ground or a floor). The support surface 100 is preferably a flat surface.

[0040] 1 to 6, the vibration meter 1 includes a case 2, a vibration sensor 3, a battery 4, a display unit 5, a handle (grip) 6, a processing unit 7, and a sensor housing unit 8. The vibration meter 1 includes sensors such as a geomagnetic sensor, a GPS sensor, a temperature sensor, and a humidity sensor in addition to the vibration sensor 3 (see FIG. 8). FIG. 4 shows a state in which the lid 11 of the case 2 is opened and the battery 4 is removed, that is, a state in which the vibration sensor 3, the processing unit 7, and the sensor housing unit 8 are housed in the case body 10. FIG. 5 shows a state in which the vibration sensor 3 and the processing unit 7 have been removed from the state shown in FIG. 4, and FIG. 6 shows a state in which the sensor housing unit 8 has been removed from the state shown in FIG. 5.

[0041] 1 to 6, the case 2 includes a case body 10, a lid 11 attached to the case body 10, a locking portion 12 (see FIG. 4, etc.), and a bottom ring 13 (see FIG. 1 to FIG. 3) attached to a bottom 10a (bottom wall 14) of the case body 10. The lid 11 is coupled to the case body 10 via a hinge H (see FIG. 2, etc.). The lid 11 closes the top surface of the case body 10 so as to be able to open and close. The locking portion 12 fixes the lid 11 to the case body 10 so as to be able to open and close. When the lid 11 is fixed to the case body 10 by the locking portion 12, the lid 11 cannot rotate relative to the case body 10. The display unit 5 is built in the lid 11. The battery 4 may be arranged on the lid 11 side (for example, in a space between the top surface of the lid 11 and the display unit 5) instead of the case body 10.

[0042] 1 to 6 (particularly FIG. 6), the case body 10 is formed in a hollow box shape. The case body 10 has an internal space 20. The case body 10 is box-shaped and has a bottom 10a and four side walls 10b. The bottom 10a includes a bottom wall 14 and a plurality of (for example, four) first leg portions 15. The bottom wall 14 is flat. A circular first through hole 16 (particularly see FIG. 6) is formed in the center of the bottom wall 14. The plurality of first leg portions 15 are arranged at the four corners of the bottom wall 14 on the lower surface of the bottom wall 14. The bottom surface of each of the first leg portions 15 is defined as a first lower end 15a.

[0043] 1 to 3, the bottom ring 13 is a circular ring in plan view. The bottom ring 13 is formed using a non-magnetic metal or synthetic resin material. The bottom ring 13 is fitted into the first through hole 16 from below. The bottom ring 13 has a second through hole 18. The inner peripheral wall of the second through hole 18 is the inner peripheral surface of the bottom ring 13. A first abutment surface (first engagement portion) 19 is formed on the inner peripheral wall of the second through hole 18. The first abutment surface 19 faces a second abutment surface (second engagement portion) 47 of the base 41 described below in the vertical direction. The first abutment surface 19 is a tapered surface that becomes lower toward the inside. The first abutment surface 19 is inclined with respect to a horizontal plane at an inclination angle of, for example, 30° to 60° (for example, 45° in the example of FIG. 1, etc.). The first abutment surface 19 is a smooth surface. The first contact surface 19 is shaped like a truncated cone. The bottom ring 13 is attached to an outer frame plate 51 of an outer frame 48 (described later) of the sensor housing unit 8. The bottom ring 13 may be fixed to the outer frame plate 51 using fastening members (not shown) such as screws.

[0044] 1 to 3 and 6, the case body 10 has a hollow rectangular parallelepiped internal space 20. The internal space 20 accommodates the vibration sensor 3, the processing unit 7, and the sensor housing unit 8.

[0045] 1 to 3, the vibration sensor 3 is, for example, an acceleration sensor, for example, a triaxial acceleration sensor that detects the magnitude of acceleration in three directions of the sensor axis. More specifically, the vibration sensor 3 is, for example, an acceleration sensor using a piezoelectric element or a quartz crystal. The vibration sensor 3 measures micro-acceleration (fine vibration). The magnitude of acceleration from the vibration sensor 3 may be output as a digital value. The vibration sensor 3 is connected to the processing unit 7 via a cable 21 (see FIG. 1). The detection output of the vibration sensor 3 is provided via the cable 21 to a control device 70 (see FIG. 8) of the processing unit 7, which will be described next.

[0046] The battery 4 is, for example, a lithium ion battery. The battery 4 may be a primary battery or a secondary battery. The battery 4 is disposed in the uppermost part of the internal space 20. The battery 4 may be disposed in another position, but is disposed in a position where the weight of the battery does not affect the position of the center of gravity of the vibration meter 1 (where the vibration meter 1 is not off-centered).

[0047] The display unit 5 has, for example, a liquid crystal display panel. This liquid crystal display panel has a liquid crystal display section 17a on the bottom surface (front surface). The liquid crystal display section 17a is, for example, an 8-inch liquid crystal display section. The display unit 5 is formed over the entire inner surface of the lid 11. Therefore, as shown in Figures 4 to 6, when the lid 11 is open, the liquid crystal display section 17a of the display unit 5 is exposed.

[0048] The handle 6 is, for example, a grip, and is attached to the upper surface of the lid 11. The vibrometer 1 can be carried by grasping the handle 6 when the lid 11 is closed. The handle 6 is a tiltable grip as shown in Figs. 1 to 3. By hanging the vibrometer 1 by the handle 6, the bottom surface of the vibrometer 1 becomes horizontal, and the vibrometer 1 can be placed (installed) as is on the placement surface 100.

[0049] The case 2 is small, and the battery 4 and the display unit 5 are also small in size. This allows the vibration meter 1 to be made small and lightweight. This makes the vibration meter 1 highly portable and easy to carry. Moreover, the handle 6 is provided, further improving portability.

[0050] 1 to 4, the processing unit 7 (see also FIG. 8) includes a vibration meter control board 22 (see also FIG. 8) and a sheet metal member 23 at the bottom and top, respectively. The vibration meter control board 22 includes a wiring board 24 and components 25 mounted on the wiring board 24. The components 25 include electric components, a terminal block, and the like. The electric components include a control device 70 (see FIG. 8), a memory unit 72 (see FIG. 8), a geomagnetic sensor, a GPS sensor, a temperature sensor, a humidity sensor, a start button 74 (see FIG. 8), an end button 75 (see FIG. 8), and the like, which will be described later. The sheet metal member 23 covers the entire area above the vibration meter control board 22 (above the wiring board 24). The sheet metal member 23 is a sheet metal member mainly for suppressing heat generation from the electric components. The vibration meter control board 22 and the sheet metal member 23 are integrally joined together using a fixing means.

[0051] 1 to 3, 5 and 6, the sensor housing unit 8 includes a base 41 that supports the vibration sensor 3 (acceleration sensor) from below, and a housing frame 42 that houses the vibration sensor 3 and the base 41. The sensor housing unit 8 houses the vibration sensor 3. The sensor housing unit 8 is housed in approximately the lower half of the internal space 20.

[0052] 1 to 3, 5 and 7, the base 41 is circular in plan view. The base 41 is attached to the bottom wall 14 of the case body 10 so as to be vertically movable. The base 41 abuts against an inner frame 49 of a housing frame 42, which will be described later, thereby restricting an upper limit position relative to the case 2. The base 41 abuts against the bottom ring 13, thereby restricting a lower limit position relative to the case 2. That is, the base 41 is vertically movable between its upper limit position and lower limit position relative to the case 2. The base 41 includes a base body 43 on which the vibration sensor 3 is placed, a case facing portion 44 that contacts the bottom ring 13, and, for example, three second legs 45.

[0053] The base body 43 is circular in a plan view. The upper surface of the base body 43 is a sensor arrangement surface 46 on which the vibration sensor 3 is arranged. The vibration sensor 3 is fixed to the sensor arrangement surface 46 using a fastening member (not shown) such as a screw. The base body 43 is formed using a non-magnetic metal or synthetic resin material.

[0054] The case facing portion 44 is circular in plan view. A ring-shaped second abutment surface (second engagement portion) 47 is formed on the peripheral portion of the lower surface of the case facing portion 44. The second abutment surface 47 is a tapered surface that becomes lower toward the inside. The second abutment surface 47 is inclined with respect to the horizontal plane at an inclination angle of, for example, 30° to 60° (for example, 45° in the example of FIG. 1, etc.). The second abutment surface 47 is a smooth surface. The second abutment surface 47 is frustum-shaped. The second abutment surface 47 is parallel to the first abutment surface 19. The case facing portion 44 is formed using a non-magnetic metal or synthetic resin material.

[0055] In this embodiment, the case facing portion 44 and the base body 43 are integrally formed. The base body 43 and the case facing portion 44 may be formed of separate members and joined to the base body 43 using a fastening member (not shown) such as a screw.

[0056] The three second leg portions 45 are disposed on the lower surface of the case facing portion 44 at equal intervals in the circumferential direction of the base 41. The three second leg portions 45 have the same height. The lower ends of the second leg portions 45 are defined as second lower ends 45a. The three second leg portions 45 are fixed to the case facing portion 44 from below by screws, pins, or the like. The base 41 is movable up and down between a lower limit position relative to the case 2 and an upper limit position relative to the case 2. The second lower ends 45a of the second leg portions 45, i.e., the second lower end 45a of the base 41, can protrude downward from the bottom surface of the bottom wall 14 of the case 2 through the second through hole 18.

[0057] 5 and 7, the housing frame 42 includes an outer frame 48 and an inner frame 49. The outer frame 48 and the inner frame 49 are formed of different sheet metals. The housing frame 48 may be fixed to the case 2 by a fastening member (not shown) such as a screw. The outer frame 48 and the inner frame 49 may be joined together by using a fastening member (not shown) such as a screw.

[0058] 7, the outer frame 48 is a box-like shape with an open top and a bottom, and includes an outer frame plate 51 having a rectangular shape in a plan view, four support columns 52 rising from the four corners of the outer frame plate 51, a left side plate 53, and a right side plate 54. Each support column 52 is L-shaped in a cross section. The left side plate 53 is connected to the two support columns 52 on the left side. The right side plate 54 is connected to the two support columns 52 on the right side. The outer frame plate 51, the four support columns 52, the left side plate 53, and the right side plate 54 are integrally formed by sheet metal. The outer frame 48 is made of aluminum, for example. In this embodiment, the upper ends of the four support columns 52 and the upper end of the right side plate 54 are all at the same height. The upper ends of the four support columns 52 and the upper end of the right side plate 54 constitute the upper end of the storage frame 42. Although not shown, the outer frame 48 may further include a connecting plate that connects the upper ends of the four support posts 52 together.

[0059] 5 and 7, the processing unit 7 is accommodated above the accommodating frame 42 in the internal space 20. The accommodating frame 42 supports the processing unit 7 from below. When the accommodating frame 42 and the processing unit 7 are accommodated in the internal space 20, the upper end of the accommodating frame 42 abuts against the lower end (lower surface) of the processing unit 7. The abutment of the upper end of the accommodating frame 42 against the processing unit 7 ensures a sufficient space above the base 41 for disposing the vibration sensor 3. In other words, the abutment of the upper ends of the four supports 52 against the processing unit 7 prevents the processing unit 7 from abutting against the vibration sensor 3.

[0060] 7, the inner frame 49 is disposed so as to cover a portion of the upper surface of the base 41. The inner frame 49 has a pair of left and right inner frame plates 56. The inner frame plates 56 are disposed so as to face each other in the front-rear direction Y. Each inner frame plate 56 has a protruding portion that protrudes upward in the middle part in the front-rear direction Y.

[0061] 7, the sensor housing unit 8 further has a restricting portion 57 for restricting the lateral movement and rotation of the base 41 relative to the housing frame 42. The restricting portion 57 includes an engagement protrusion 58 coupled to the upper surface of the base 41 and an engagement recess 59 formed in each inner frame plate 56. The engagement recess 59 is an engagement hole in the example of FIG. 7, but may be an engagement groove. The engagement protrusion 58 and the engagement recess 59 engage with each other to restrict the lateral movement and rotation of the base 41 relative to the housing frame 42 within a predetermined range. The engagement protrusion 58 and the engagement recess 59 are kept engaged with each other regardless of the vertical position of the base 41 (whether the base 41 is in the position shown in FIG. 1 and FIG. 2 or in the position shown in FIG. 3). Although not shown, the engagement recess 59 may be formed in the outer frame 48 instead of the inner frame 49. Although not shown, the engagement protrusion 58 may be formed on the housing frame 42 side, and the engagement recess 59 may be formed on the base 41 side.

[0062] 1 to 3 (particularly FIG. 3), a first distance H1 between the first contact surface 19 and the first lower end 15a is shorter by several mm to several tens of mm (for example, about 5 mm) than a second distance H2 between the second contact surface 47 and the second lower end 45a. Specifically, the first distance H1 between a predetermined position on the first contact surface 19 and a position on the second contact surface 47 where the first contact surface 19 can contact the predetermined position is shorter than the second distance H2 between the second contact surface 47 and the second lower end 45a.

[0063] The state of the vibrometer 1 placed on the mounting surface 100 (the state shown in FIG. 1 and FIG. 2) is referred to as a mounting state. The base 41 is movable up and down between its upper limit position and its lower limit position relative to the case 2. In this mounting state, the second lower end 45a of the base 41 abuts against the mounting surface 100 via the second through hole 18. In this mounting state, the first lower end 15a of the case 2 and the second lower end 45a of the base 41 are at the same height. As described above, the first distance H1 between the first abutment surface 19 and the first lower end 15a is shorter than the second distance H2 between the second abutment surface 47 and the second lower end 45a. Therefore, in a mounted state in which the case 2 and the base 41 are mounted on the mounting surface 100 (the state shown in FIGS. 1 and 2), the first contact surface 19 and the second contact surface 47 do not contact (engage) with each other, and a gap S (see FIG. 3) is formed between the first contact surface 19 and the second contact surface 47. This gap S may be several millimeters to several tens of millimeters (a distance in the vertical direction Z). In the mounted state of the vibrometer 1, the base 41 is not in contact with the case facing portion 44, and therefore the base 41 is not supported by the case facing portion 44.

[0064] In this placed state, the sensor placement surface 46 of the base 41 does not abut against the inner frame 49 (inner frame plate 56). The size of the inner frame plate 56 is adjusted so that the sensor placement surface 46 does not abut against the inner frame 49 (inner frame plate 56) in the placed state.

[0065] In this placed state (the state shown in FIGS. 1 and 2), the base 41 supports the vibration sensor 3 housed in the internal space 20 independently from the case 2. In this placed state, not only is the vibration sensor 3 not in contact with the case 2, but the vibration sensor 3 and the case 2 are not connected to each other. In other words, the vibration sensor 3 is physically separated from the case 2.

[0066] When transporting the vibrometer 1, the worker lifts the vibrometer 1. In this case, the worker lifts the vibrometer 1 by gripping the handle 6. As the case 2 is lifted upward, the bottom ring 13 of the case 2 moves upward relative to the base 41. Then, the first abutment surface 19 of the bottom ring 13 of the case 2 abuts against the second abutment surface 47 of the base 41, so that the bottom ring 13 comes into contact with the base 41 as shown in FIG. 3. Then, the case 2 is lifted further upward. That is, as the worker lifts the vibrometer 1 by holding the handle 6, the base 41 can be placed in the bottom ring 13 without shifting.

[0067] The state of the vibrometer 1 in which the case 2 is lifted upward (the state shown in FIG. 3) is referred to as the lifted state. In this lifted state, the first abutment surface 19 and the second abutment surface 47 are in contact with each other. In the lifted state of the vibrometer 1 (the state shown in FIG. 3), the base 41 is supported in contact with the bottom ring 13 of the case 2. That is, in the lifted state of the vibrometer 1 (the state shown in FIG. 3), the vibration sensor 3 and the base 41 are supported by the case 2. In other words, the vibration sensor 3 and the base 41 are supported in a suspended manner by the case 2.

[0068] As described above, pedestal 41 is vertically movable relative to case 2. The height position of pedestal 41 relative to case 2 differs between the placed state of vibrometer 1 (the state shown in FIGS. 1 and 2) and the raised state of vibrometer 1 (the state shown in FIG. 3). When vibrometer 1 is placed (the state shown in FIGS. 1 and 2), pedestal 41 is in a lower position. When vibrometer 1 is raised (the state shown in FIG. 3), pedestal 41 is in an upper position.

[0069] FIG. 8 is a block diagram showing an electrical configuration of the vibration meter 1. The vibration meter 1 includes a control device 70. The control device 70 includes a microcomputer. More specifically, the control device 70 includes an arithmetic unit 71, a storage unit, a timer, and the like. The arithmetic unit 71 includes a processor. The processor includes a GPU (Graphic Processing Unit), a CPU (Central Processing Unit), and the like. The storage unit includes a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The control device 70 is connected to a storage unit 72. The storage unit 72 is composed of a storage device such as a non-volatile memory or a hard disk drive. The storage unit 72 stores various information. The storage unit 72 stores a program that can be executed by the arithmetic unit 71 of the control device 70.

[0070] The control device 70 is connected to the vibration sensor 3. The control device 70 stores the detection output of the vibration sensor 3 in a storage unit 72 as recorded data 73. The detection output of the vibration sensor 3 is stored in the recorded data 73 in a form linked to the detection time and other measurement conditions. In addition, a geomagnetic sensor, a GPS sensor, a temperature sensor, a humidity sensor, etc. are connected to the control device 70.

[0071] In this embodiment, the control device 70 converts the three-direction output values ​​of the vibration sensor 3 (acceleration sensor) from the coordinate system of the three sensor axes into a predetermined orthogonal coordinate system (second orthogonal coordinate system) so that the direction of gravitational acceleration coincides with the Z axis. The control device 70 also converts the converted acceleration values ​​into a predetermined orthogonal coordinate system (first orthogonal coordinate system) different from the above orthogonal coordinate system so that the sensor axis (y axis) of the vibration sensor 3 (acceleration sensor) faces north (magnetic north).

[0072] A start button 74 and an end button 75 are connected to the control device 70. The control device 70 starts measurement by the vibration sensor 3 based on an input of an operation signal of the start button 74. The control device 70 ends measurement by the vibration sensor 3 based on an input of an operation signal of the end button 75.

[0073] In this embodiment, the acceleration sensor 13 is configured by a three-axis acceleration sensor. The acceleration sensor 13 measures the acceleration including the gravitational acceleration. Therefore, the vibration meter 1 can grasp the inclination of the acceleration sensor 3 based on the acceleration values ​​in the three directions of the sensor axis output by the acceleration sensor 3. The vibration meter 1 also includes a geomagnetic sensor. Therefore, the vibration meter 1 can grasp the horizontal direction of the vibration meter 1. Then, the control device 70 converts the acceleration values ​​of the coordinate system of the three directions of the sensor axis output from the acceleration sensor 3 into a predetermined orthogonal coordinate system. This coordinate conversion of the acceleration is performed using the method disclosed in JP 2022-171245 A. As a result, regardless of the inclination or orientation of the vibration meter 1, the acceleration magnitude in the three directions of the north-south direction, the east-west direction, and the vertical direction acting on the vibration meter 1 can be measured well.

[0074] 9 is a flow chart showing the flow of a vibration measurement process using the vibration meter 1. The flow of a vibration measurement process using the vibration meter 1 will be described with reference to FIGS.

[0075] An operator installs (places) the vibrometer 1 on a mounting surface 100 such as the ground, a floor, or a desk at a predetermined measurement point. The cable 21 connected to the vibration sensor 3 is already accommodated in the internal space 20. Therefore, it is not necessary to insert or remove the cable 21 every time the vibrometer 1 is installed. Since the direction of acceleration is converted to horizontal / vertical, it is not necessary to perform level adjustment to make the vibrometer 1 horizontal, and it is also not necessary to adjust the direction of the vibrometer 1 to match magnetic north. Therefore, the preparation work for installing the vibrometer 1 is simplified and the troublesomeness of the preparation work is reduced. Moreover, since the cable 21 is not routed outside the case 2, problems resulting from this can be avoided.

[0076] In the placed state of the vibration meter 1 (the state shown in FIGS. 1 and 2), the base 41 supports the vibration sensor 3 housed in the internal space 20 independently from the case 2. In the placed state of the vibration meter 1, the vibration sensor 3 is physically separated from the case 2, and therefore vibration is not transmitted from the case 2 to the vibration sensor 3. This allows the vibration meter 1 to measure vibration with high accuracy. Therefore, it is possible to provide a vibration meter 1 that has excellent portability and can achieve high-accuracy vibration measurement.

[0077] During vibration measurement, it is possible that the case 2 may vibrate slightly due to the influence of wind or other devices. However, even in such a case, the minute vibrations are not transmitted from the case 2 to the vibration sensor 3, so no error occurs in the detection output of the vibration sensor 3. This makes it possible to maintain high accuracy in vibration measurement by the vibration meter 1.

[0078] Also, the first distance H1 between the first contact surface 19 and the first lower end 15a is shorter than the second distance H2 between the second contact surface 47 and the second lower end 45a. Therefore, in a mounted state (the state shown in FIG. 1 and FIG. 2) in which the case 2 and the base 41 are mounted on the mounting surface 100 consisting of a horizontal plane, a gap S is formed between the first contact surface 19 and the second contact surface 47. Therefore, in a mounted state in which the case 2 and the base 41 are mounted on the mounting surface 100, the vibration sensor 3 can be reliably physically separated from the case 2. The vibration measurement by the vibration meter 1 is performed in the mounted state of the vibration meter 1. Therefore, the vibration measurement can be performed in a state in which the vibration sensor 3 is reliably physically separated from the case 2.

[0079] After placing the vibration meter 1, the worker operates the start button 74. When the start button 74 is operated (YES in step S1 in FIG. 9), the control device starts outputting the detection output of the vibration sensor 3 (step S2 in FIG. 9). The control device 70 does not immediately start recording the detection output even when the start button 74 is operated. Then, when 30 seconds have elapsed since the operation of the start button 74 (YES in step S3 in FIG. 9), the control device 70 starts recording the detection output of the vibration sensor 3 (step S4 in FIG. 9). The detection output is recorded in the record data 73. At this time, the control device 70 starts recording not only the detection output of the vibration sensor 3 but also the detection outputs of other sensors (geomagnetic sensor, GPS sensor, temperature sensor, humidity sensor, etc.) in the record data 73.

[0080] Furthermore, after a predetermined period (e.g., 30 seconds) has elapsed since the start button 74 was operated, recording of the detection output is started. As described above, in the placed state of the vibration meter 1 (the state shown in Figs. 1 and 2), the vibration sensor 3 is physically separated from the case 2. However, there is a possibility that the impact caused by the operation of the start button 74 by the operator or the vibration caused by the operator's walking may be transmitted from the case 2 through the placement surface 100 to the base 41, and then from the base 41 to the vibration sensor 3. In this case, the vibration sensor 3 may detect this vibration, and an error may occur in the detection output of the vibration sensor 3. Therefore, if recording of the detection output is started immediately after the start button 74 is operated, the detection output with an error may be recorded in the recorded data 73.

[0081] In this embodiment, a predetermined period of time is waited until recording of the detection output starts after the start button 74 is operated. Then, recording of the detection output starts after the impact caused by operating the start button 74 subsides. This makes it possible to obtain recorded data 73 that is free from the influence caused by operating the start button 74.

[0082] When it is time to end the measurement process, the operator operates the end button 75. When the end button 75 is operated (YES in step S5 in FIG. 9), the control device 70 ends the detection output of the vibration sensor 3 and ends storage of the detection output (step S6 in FIG. 9).

[0083] Thereafter, the worker grasps the handle 6, lifts the vibrometer 1, and carries it to the next measurement position.

[0084] In this lifted state of the vibration meter 1 (the state shown in FIG. 3), the first contact surface 19 and the second contact surface 47 come into contact (engage). Since the first contact surface 19 and the second contact surface 47 are frustum-shaped, the movement of the base 41 in the lateral direction (the left-right direction X and the front-back direction Y) relative to the case 2 is restricted in the state in which the first contact surface 19 and the second contact surface 47 are in contact. This makes it possible to restrict the movement of the vibration sensor 3 and the base 41 relative to the case 2 in the lifted state of the vibration meter 1 (see FIG. 7). Therefore, the vibration meter 1 can be carried while effectively restricting the movement of the vibration sensor 3 and the base 41 relative to the case 2. This makes it possible to further improve the portability of the vibration meter 1.

[0085] However, since the vibration sensor 3 of the vibrometer 1 is housed in the case 2, the following problem occurs when the vibrometer 1 is transported. That is, due to vibrations during transportation of the vibrometer 1, the vibration sensor 3 may wobble in the case 2 and collide with other members in the case 2. If the impact is large, the vibration sensor 3 may be damaged. This problem becomes apparent especially in the case of a crystal type (quartz type) acceleration sensor or a piezoelectric element type sensor used as the vibration sensor 3, which is vulnerable to impacts. In order to prevent such problems from occurring, the vibrometer 1 is provided with a protective cover 80 that is attached during transportation. FIG. 10 is a perspective view of the protective cover 80.

[0086] 3 and 10, when the vibration meter 1 is transported, a protective cover 80 is attached to the bottom 10a of the vibration meter 1. The protective cover 80 includes a rectangular frame 81 having a rectangular shape in a plan view, four spacer ribs 82, four third legs 83, and fastening bolts 84 (see FIG. 3). In FIG. 3, the protective cover 80 is indicated by a two-dot chain line. The protective cover 80 has two functions: a function of positioning (fixing) the base 41 (i.e., the base 41 and the vibration sensor 3) to the bottom ring 13, and a function of protecting the bottom 10a of the vibration meter 1.

[0087] 1 to 3, bottom ring 13 has a circular ring shape in a plan view. Bottom ring 13 is formed using a non-magnetic metal or synthetic resin material. Bottom ring 13 is fitted into first through hole 16 from below. Bottom ring 13 has a second through hole 18. The inner peripheral wall of second through hole 18 is the inner peripheral surface of bottom ring 13. The inner peripheral wall of second through hole 18 is provided with a first abutment surface ( Case side contact surface, The first contact surface 19 is formed with a second contact surface ( Base side contact surface, The bottom ring 13 faces the second engagement portion 47 vertically. The first abutment surface 19 is a tapered surface that becomes lower toward the inside. The first abutment surface 19 is inclined at an inclination angle of, for example, 30° to 60° (for example, 45° in the example of FIG. 1 etc.) with respect to the horizontal plane. The first abutment surface 19 is a smooth surface. The first abutment surface 19 is frustum shaped. The bottom ring 13 is attached to an outer frame plate 51 of an outer frame 48 of the sensor accommodating unit 8, which will be described later. The bottom ring 13 may be fixed to the outer frame plate 51 using a fastening member (not shown) such as a screw.

[0088] 3, a protective cover 80 is attached to cover the entire bottom 10a of the vibrometer 1. By protecting the bottom 10a of the vibrometer 1 with the protective cover 80, it is possible to suppress or prevent the transmission of shock to the vibration sensor 3.

[0089] With the protective cover 80 attached, the four 1 leg 15 are accommodated in the corresponding leg accommodating recesses 88. In addition, when the protective cover 80 is attached, the bolt holes 89 of the base 41 face the bolt insertion holes 87 of the metal plate 85 in the vertical direction. Then, the bolts 84 are screwed into the bolt holes 89 through the bolt insertion holes 87. As a result, the bolts 84 are fastened to the bolt holes 89. When the amount of screwing of the bolts 84 increases, the heads of the bolts 84 and the base 41 approach each other while the distance between the metal plate 85 and the bolt holes 89 is kept constant by the spacer ribs 82. Therefore, the base 41 is pressed against the bottom ring 13, and the base 41 can be positioned (fixed) to the bottom of the case 2. Therefore, the vibration sensor 3 can be suppressed or prevented from wobbling in the internal space 20. Therefore, the vibration meter 1 can be easily transported.

[0090] Fig. 11 is a schematic cross-sectional view of a main part of a vibrometer 201 according to a second embodiment of the present invention, and corresponds to Fig. 2. Fig. 12 is a graph for explaining the characteristics of a viscous sheet 211. In the second embodiment, parts corresponding to those shown in the first embodiment are denoted by the same reference symbols as in Figs. 1 to 10, and their explanations will be omitted. The vibrometer 201 differs from the vibrometer 1 in that a viscous sheet 211 is disposed between each of the vibration sensors 3 and the base 41.

[0091] A first viscous sheet 211 is disposed between the vibration sensor 3 and the base 41. The first viscous sheet 211 is disposed over the entire area between the vibration sensor 3 and the base 41.

[0092] The viscous sheet 211 is a sheet having high viscosity. The viscous sheet 211 is a sheet that absorbs vibrations and is a shock absorbing sheet. The viscous sheet 211 is formed using, for example, urethane gel.

[0093] According to the second embodiment, even if a large impact is applied to the case 2, the impact is absorbed by the viscous sheet 211. This makes it possible to reduce or eliminate the impact transmitted from the case 2 to the vibration sensor 3. This makes it possible to protect the vibration sensor 3. Therefore, even if a large impact is applied to the case 2, it is possible to suppress or prevent the impact from being transmitted to the vibration sensor 3, thereby making it possible to prevent damage to the vibration sensor 3.

[0094] The viscous sheet 211 is, for example, a Hypergel sheet (manufactured by Exseal Co., Ltd.). Any one of Sample 1, Sample 2, and Sample 3 in FIG. 12 is used as the viscous sheet 211. Sample 1, Sample 2, and Sample 3 may be "Hypergel 30" (product name), "Hypergel 50" (product name), and "Hypergel 70" (product name) of Hypergel sheets (manufactured by Exseal Co., Ltd.), respectively. As shown in FIG. 12, in all of Samples 1 to 3, the vibration transmissibility is high at 30 Hz or less and low at 50 Hz or more. The frequency range to be measured using the vibrometer 201 is 10 Hz or less. On the other hand, the frequency range due to impact is 50 Hz or more. That is, by using the viscous sheet 211 having a low vibration transmissibility in the frequency range due to impact (50 Hz or more) and a high vibration transmissibility in the frequency range to be measured (10 Hz or less), the vibration sensor 3 can be prevented from being damaged while maintaining a high accuracy of the vibration measurement by the vibrometer 201.

[0095] Although a number of embodiments of the present invention have been described above, the present invention can be embodied in other forms.

[0096] For example, the first contact surface 19 and the second contact surface 47 have been described as having a truncated cone shape, but as long as both are annular tapered surfaces, they do not have to have a truncated cone shape.

[0097] In addition, the first contact surface 19 and the second contact surface 47 have been described as being tapered surfaces, but the first contact surface 19 and the second contact surface 47 may have horizontal surfaces instead of tapered surfaces. In this case, the first contact surface 19 and the second contact surface 47 may be circular or other annular in plan view.

[0098] The present invention is not limited to the contents of the above-described embodiment, and various modifications are possible within the scope of the claims. [Explanation of symbols]

[0099] 1: Vibration meter 2: Case 3: Vibration sensor 6: Handle (grip) 7: Processing unit 10a: bottom 15a: 1st bottom end 19: First contact surface (first engagement part) 20: Interior space 41: Pedestal 45a: 2nd bottom end 47: Second contact surface (second engagement part) 80: Protective cover 201: Vibration meter 211: Viscous sheet H1: 1st distance H2: 2nd distance

Claims

1. A vibrometer for measuring vibrations while being placed on a mounting surface, comprising: a case having an internal space; A vibration sensor accommodated in the internal space; a processing unit that is accommodated in the internal space and performs measurement processing based on a detection output output from the vibration sensor; a base for supporting the vibration sensor, the base having legs that come into contact with a mounting surface, the base being movable up and down together with the vibration sensor accommodated in the internal space relative to the case and the processing unit; a base-side contact surface formed on the base and tapered downward toward the inside of the base; a tapered case-side abutment surface formed on the case, facing the base-side abutment surface from above and below, and aligned with the base-side abutment surface; When the vibrometer is separated from the mounting surface, the base contact surface and the case contact surface are in surface contact with each other, A vibrometer, wherein the vibration sensor and the base are not supported by the case when the vibrometer is placed on the placement surface.

2. A through hole is formed in the case, the through hole vertically penetrating a bottom wall of the case, The vibrometer according to claim 1 , wherein a lower end of the base is capable of protruding below the case through the through hole.

3. A vibration meter as described in claim 1, wherein a first distance from a first lower end of the case side abutment surface is shorter than a second distance from a second lower end of the base side abutment surface.

4. The vibrometer according to claim 1 , wherein the case-side contact surface and the base-side contact surface are frustum-shaped.

5. The vibrometer of claim 1 or 4, further comprising a viscous sheet disposed between the vibration sensor and the base.

6. The base is circular in plan view, The legs are multiple; The vibrometer according to claim 1 , wherein the legs are arranged at intervals in a circumferential direction of the base in a plan view except for a center of the base.

7. A vibrometer for measuring vibrations, comprising: a case having an internal space; A vibration sensor accommodated in the internal space; a processing unit that is accommodated in the internal space and performs measurement processing based on a detection output output from the vibration sensor; a base for supporting the vibration sensor, the base being capable of supporting the vibration sensor housed in the internal space independently from the case; The vibration meter further includes a protective cover that covers a bottom of the case and is connectable to the base in a screw-tight manner.

Images