JP4122443B2 - Elastic modulus measuring device and composite sensor - Google Patents

Description

The present invention relates to an elastic modulus measuring apparatus and a composite sensor , and more particularly to an elastic modulus measuring apparatus that measures an elastic modulus by applying a vibration wave to a sample that is a measurement object whose elastic modulus is measured.

  The elastic modulus is a ratio between stress and strain within an elastic range when an external force is applied to the material to deform it. One of the elastic moduli is Young's modulus, which is a ratio of tensile stress when a material is stretched to elongation of a substance per unit length. As a method for measuring the Young's modulus, there is a technique shown in Non-Patent Document 1. FIG. 9 is a block diagram illustrating a configuration of an apparatus related to the technique of Non-Patent Document 1.

In FIG. 9, a sample 6 as a measurement object is suspended by an exciter 5 and a vibration detector 8. In order to excite the sample 6, the vibration frequency from the low-frequency transmitter 3 is continuously changed, and a frequency that matches the fundamental vibration (natural frequency) of the sample 6 is measured. The Young's modulus can be obtained from the frequency . Further, by covering the sample 6 with the electric furnace 7, it is possible to measure the elastic modulus at a high temperature.

  Japanese Patent Application Laid-Open No. H10-228688 shows a technique for giving a white noise signal to concrete as a sample and determining deterioration of the concrete. In Patent Literature 2, a white noise signal is given from a speaker that is kept at a certain distance to concrete as a sample, and a sound reflected by the concrete is received by a microphone. The received sound is displayed as a waveform, and the waveform is analyzed and compared with a reference value measured in advance to determine whether or not the concrete has deteriorated.

  Patent Document 3 shows a technique for hitting a sample with a hammer and measuring a defective portion of the sample with the sound. In Patent Document 3, a sample that is an object to be measured is hit with a hammer, and a hitting sound generated at that time is received by a microphone attached to the same hammer. The received sound is divided into frequency bands and is a technique for outputting sound and images from a speaker attached to a hammer.

  Patent Document 4 shows a technique for measuring a cracked portion of concrete. In Patent Document 4, a transmitter and a receiver are arranged at a fixed distance, ultrasonic waves are sent from the transmitter to the concrete, and sound waves reflected by the opposite surface of the concrete are received by the receiver. This is a technique for identifying cracks in concrete.

Yuzo Nishikawa, Akio Ikeda, “Abrasion of Ferrite Sintered Body and Temperature Change of Internal Friction”, Journal of Ceramic Industry Association, Japan, Japan Ceramic Society, October 2, 1970, Vol. 78, No. 900, p256 263 Japanese Patent No. 3510835 JP 2003-66014 A Japanese Patent Laid-Open No. 64-65407

However, since the elastic modulus is the ratio of stress and strain when the material is deformed, the concept of stress cannot be ignored when measuring the elastic modulus. Therefore, as shown in Non-Patent Document 1, it is necessary to actually apply stress to the material to deform it. Therefore, in the technique of Non-Patent Document 1, vibration is actually applied to the sample, and the frequency that matches the fundamental vibration (natural frequency) of the sample is measured while scanning the frequency by gradually changing the frequency . It was necessary, and processing took time and effort.

  In addition, depending on the material of the wire on which the sample is suspended, vibrations are difficult to be transmitted. In particular, when measuring at a high temperature, the suspended wires need to have heat resistance, and vibrations may be difficult to be transmitted. Furthermore, when measuring at a high temperature, as shown in FIG. 9, it is necessary to cover the measurement space with an electric furnace 7. However, since the sample 6 is suspended from two places, the sample 6 is suspended. It is necessary to make two holes in the electric furnace 7 for passing the existing wire. If it does so, it will become easy to escape heat and thermal efficiency will worsen. Furthermore, since the sample 6 is suspended from two places, there is a possibility that a failure may occur due to an incorrect connection line between the exciter 5 and the vibration detector 8.

  The technique of Patent Document 2 is a device that measures deterioration by giving a white noise signal, and is not a device that measures elastic modulus. In addition, a distance sensor and a moving means are provided in order to stably apply a vibration wave to the sample, and the work is troublesome because the apparatus is upsized.

  In the technique of Patent Document 3, since the sample is hit with a hammer, the sample may be damaged. In addition, since the place where the hammer and the sample make a sound and the place where the microphone for receiving the sound is provided are separated, there is a possibility that the measurement cannot be performed strictly.

The technique of patent document 4 measures the deterioration location of concrete, and is not the technique which measures the frequency which matched the fundamental vibration (natural frequency) of the sample by the vibration . In addition, since the receiver and the transmitter are installed at locations apart from each other, work is troublesome.

Thus, the present invention provides elasticity modulus of the sample that is the measuring object, it can with stress can be measured instantaneously without using the measured reliably modulus regardless is troublesome work rate measuring apparatus, and aims to provide a composite sensor.

According to a first aspect of the present invention, there is provided a vibrating means that vibrates the sample by applying a vibration wave to a sample that is a measurement object of an elastic modulus, and the sample generated by the vibration wave provided by the vibrating means . and a receiving means for receiving waves of the natural vibration, an elastic modulus measuring device for calculating the modulus of elasticity of the sample on the basis of the wave of the signal of the natural frequency of the sample received by the receiving means, the vibrating The vibration wave given to the sample by the means is a noise signal, the excitation means includes a first member extending in a direction in which the vibration wave given to the sample propagates, and the reception means A second member extending in a direction in which a wave of the natural vibration of the sample generated by the vibration of the sample propagates, wherein the first member and the second member are arranged side by side with a cushioning material interposed therebetween, and the first member End point of the direction of propagation of the vibration wave propagating through Contact portions where one end of the first member of the first member and one end of the second member on the starting point side in the direction of propagation of the natural vibration wave of the sample propagating through the second member are in contact with the sample. It is an elasticity-modulation measuring device characterized by having .

Conventionally, since it is necessary to apply stress to deform the sample in order to measure the elastic modulus, the sample was actually deformed by applying vibration to the sample. The measuring device ignores the concept of stress and calculates the elastic modulus by accurately measuring the frequency that matches the natural frequency of the sample with sound (noise signal) without any variation, thereby obtaining accurate elasticity instantaneously. The rate can be obtained.

According to a second aspect of the present invention, there is provided a vibrating means that vibrates the sample by applying a vibration wave to a sample that is a measurement object of the elastic modulus, and the sample generated by the vibration wave provided by the vibrating means . In a composite sensor comprising a receiving means for receiving a natural vibration wave , the excitation means comprises a first member extending in a direction in which a vibration wave applied to the sample propagates, and the receiving means A second member extending in a direction in which the wave of the natural vibration of the sample generated by the vibration of the sample propagates, wherein the first member and the second member are arranged side by side with a cushioning material interposed therebetween; Each member has a cross-section when the cross-sectional area on the start point side in the direction in which the vibration wave propagates is equal to or larger than the cross-sectional area on the end point side, and projection is performed from the start point side toward the end point side. Having a shape included in the area of the cross section on the start point side, 2 members, in the following the magnitude of the cross-sectional area size of the end point of the start point side cross-sectional area of the direction in which the waves of the natural vibration is propagated in said sample, and the projection is performed toward the end point to the starting point side Each of the cross sections has a shape included in a region of the cross section on the end point side, and one end portion of the first member on the end point side in the direction in which the vibration wave propagating through the first member propagates and the second Each of the one end portions of the second member on the starting point side in the direction in which the wave of the natural vibration of the sample propagating through the member propagates has a contact portion in contact with the sample.

By using the composite sensor according to claim 2 described above, the wave of the natural vibration of the sample generated by the vibration wave directly applied to the sample can be directly received at the given site, so that In addition, it is possible to accurately capture the natural vibration wave .

According to the present invention, since the elastic modulus is measured by giving a noise signal to the sample of the measurement object, it is not necessary to scan the frequency by gradually changing the frequency as in the conventional technique. , it can be determined frequency that matches the natural frequency of the sample instantly. Therefore, it is possible to shorten the time without taking time and effort. Moreover, since there is no need to actually hit the sample with a hammer or the like, the sample is not damaged. Further, by using a noise signal, a change in waveform can be measured in real time.

  In addition, according to the present invention, since a vibration sensor and a receiving unit are used as an integral structure, it is necessary to make only one hole in the heat insulating material at the time of measurement at a high temperature. Thermal efficiency is improved compared to the case where a hole is made in a location.

  Furthermore, since the composite sensor in which the excitation unit and the reception unit are integrated is used, it is possible to reduce the possibility that the apparatus breaks down due to wrong connection destinations.

  Furthermore, by using a composite sensor in which the excitation unit and the reception unit are integrated, the elastic modulus can be measured even for a sample of a minute size that could not be measured conventionally.

Furthermore, by measuring the composite sensor in contact with the sample, the vibration wave can be reliably propagated, and the natural vibration wave of the sample can be reliably received to measure the frequency that matches the natural frequency of the sample. Can do.

  Further, by measuring the composite sensor in contact with the sample, a distance sensor and moving means are not required, and the work can be saved by making the apparatus compact.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a block diagram showing an example of the configuration of the elastic modulus measuring apparatus according to the first embodiment of the present invention.

The elastic modulus measuring apparatus 100 includes a white noise generator 102, a first filter 104, a power amplifier 106, an excitation sensor 108, a reception sensor 110, an amplifier 112, a second filter 114, an FFT analyzer 116, and an elastic modulus calculator 118. Is provided. The vibration sensor 108 gives a white noise signal to the sample 101, and the reception sensor 110 receives the natural vibration of the sample generated by the given white noise signal. Further, as a result of analysis by the FFT analyzer 116, a graph 122 and a frequency 124 are displayed, and the elastic modulus calculation unit 118 calculates the elastic modulus based on the displayed results. As a result, elastic modulus data 120 is output.

  Next, processing of the elastic modulus measuring apparatus 100 in FIG. 1 will be described. First, a white noise signal is generated by the white noise generator 102 which is a noise circuit. The generated white noise signal is filtered by the first filter 104. At this time, the frequency width of the driving range of the vibration sensor 108 is set. For example, if it is a low-pass filter, it is set to 10000 Hz to remove high-frequency noise, and if it is a high-pass filter, it is set to 100 Hz to remove low-frequency noise.

  When the white noise signal is filtered by the first filter, the power amplifier 106 amplifies the white noise signal and supplies the vibration sensor 108 with power necessary for driving the vibration sensor 108. Then, the vibration sensor is driven to give a white noise signal to the sample 101.

The sample 101 is vibrated by the white noise signal provided from the vibration sensor 108, and thus a natural vibration wave is generated. The reception sensor 110 receives the generated natural vibration wave and detects it as a voltage proportional to the received wave. The detected voltage is amplified by the amplifier 112. The signal of the received wave as a voltage amplified by the amplifier 112 is analyzed by the FFT analyzer 116 through the second filter 114 set to a bandwidth necessary for analysis.

  The FFT analyzer 116 performs fast Fourier transform processing. As a result, a graph 122 with the horizontal axis representing frequency and the vertical axis representing signal intensity is displayed on the screen, and the frequency 124 at the maximum signal intensity is also displayed. The graph of FIG. 8 is a graph analyzed by the FFT analyzer 116. The details of the graph of FIG. 8 will be described later together with the description of the measurement results obtained by the elastic modulus measuring apparatus of the present invention. Based on the result displayed by the FFT analyzer 116, the elastic modulus calculator 118 calculates the elastic modulus. The calculation of the elastic modulus will be described later together with the description of the measurement result by the elastic modulus measuring device of the present invention. Then, the elastic modulus data 120 of the calculation result is output, and the elastic modulus measurement process is terminated.

  As an excitation method and a reception method in the present invention, as shown in FIG. 9, the sample is suspended by the excitation sensor 108 and the reception sensor 110 in FIG. May be measured.

  In addition, as an excitation method and a reception method in the present invention, the sample is supported by two fulcrums from below, and is excited from the center of the sample and received at the end of the sample to measure the elastic modulus. May be.

  Further, in the above method, the vibration sensor may be a speaker and the reception sensor may be a microphone.

  Furthermore, in the present invention, the sample may be an indeterminate material such as cement or a shaped material such as metal.

  Further, in the first embodiment of the present invention, the white noise signal is used as the noise signal, but a noise signal other than the white noise signal such as a pink noise signal, a flat random noise signal, or a burst noise signal may be used. Absent.

  The second embodiment of the present invention will be described below. FIG. 2 is a block diagram showing an example of the configuration of the elastic modulus measuring apparatus according to the second embodiment of the present invention.

The elastic modulus measuring apparatus 200 includes a white noise generator 202, a first filter 204, a power amplifier 206, a composite sensor 208, an amplifier 210, a second filter 212, an FFT analyzer 214, and an elastic modulus calculator 216. The composite sensor 208 is in contact with the sample 201, gives a white noise signal to the sample from the vibration unit, and receives the natural vibration of the sample generated by the given white noise signal. Similarly to the first embodiment, the graph 220 and the frequency 222 are displayed by the FFT analyzer 214, and the elastic modulus calculation unit 216 calculates the elastic modulus. Then, elastic modulus data 218 is output.

  Since the processing of the elastic modulus measuring apparatus 200 is the same as that of the first embodiment, the description thereof is omitted.

  Next, the configuration of the composite sensor 208 in FIG. 2 will be described. 3 and 4 are diagrams showing an example of the configuration of the composite sensor 208 of FIG. FIG. 3 is a cross-sectional view of the composite sensor 208 of FIG. 2 cut in the vertical direction. 4 is a cross-sectional view taken along the line IV-IV for the composite sensor 208 of FIG.

  In FIG. 3, the upper portion 302a of the vibration sensor probe 302 has a semi-elliptical column shape, and the lower portion 302b of the vibration sensor probe 302 has a shape of an inverted semi-elliptical frustum. Similarly, in the reception sensor probe 304, the upper portion 304a has a semi-elliptical column shape, and the lower portion 304b of the reception sensor probe 304 has a reverse semi-elliptical frustum shape. The vibration sensor probe 302 and the reception sensor probe 304 are arranged in close contact with each other with a flat plate-like buffering prevention material 306 sandwiched between flat portions 302e and 304e on the side surfaces. The vibration sensor probe 302 and the reception sensor probe 304 are made of stainless steel, and the anti-buffer material 306 is a material that can prevent vibrations such as urethane rubber.

  The vibration sensor probe 302 extends in the direction in which the vibration wave propagates as shown in the figure. Here, when the cross-sectional area of the end point 302c in the direction in which the vibration wave propagates when projected from the direction in which the vibration wave propagates is S2, the start point in the direction in which the vibration wave propagates compared to the size of the cross-sectional area S2 The size of the cross-sectional area S1 of the portion 302d is large. In addition, the cross-sectional area of the end point 302c is included in the cross-sectional area of the start point 302d. In addition, about the relationship between the said cross-sectional areas S1 and S2, both may be equal.

  On the other hand, the reception sensor probe 304 extends in the direction in which the reception wave propagates as shown in the figure. Here, when the cross-sectional area of the end point 304d in the direction in which the received wave propagates when projected from the direction in which the received wave propagates is S3, the start point in the direction in which the received wave propagates compared to the size of the cross-sectional area S3. The size of the cross-sectional area S4 of the portion 304c is small. In addition, the cross-sectional area of the start point part 304c is included in the cross-sectional area of the end point part 304d. In addition, about the relationship between sectional area S3 and S4, both may be equal.

The end point portion 302c of the vibration sensor probe 302 and the start point portion 304c of the reception sensor probe 304 are respectively brought into contact with the sample 322 as contact portions, and measurement is performed in the contact state. By doing so, the vibration wave from the vibration sensor probe 302 is reliably transmitted to the sample 322, and the reception sensor probe 304 reliably receives the wave of the natural vibration of the sample 322 generated by the vibration wave. Can do.

  An excitation vibrator (piezoelectric element) 312 having a cylindrical shape for generating a vibration wave is provided at the starting point portion 302 d of the vibration sensor probe 302. The vibration vibrator 312 is electrically connected to the power amplifier 206 of FIG. A stable oscillation frequency can be obtained by the vibration vibrator 312. In addition, a receiving vibrator (piezoelectric element) 310 having a cylindrical shape is provided at the end point portion 304d of the receiving sensor probe 304 to electrically detect the received vibration by the piezoelectric effect. Similarly to the vibrating vibrator 312, the receiving vibrator 310 is electrically connected to the amplifier 210 of FIG. The exciting conductor 314 and the receiving conductor 316 are housed in an insulated state in the cable 327 and are electrically connected to external devices.

  The sensor unit 324 formed by the vibration sensor probe 302, the reception sensor probe 304, the vibration transducer 312, the reception transducer 310, and the buffering prevention material 306 has a substantially elliptical shape at the top. The lower part has a substantially inverted elliptic frustum shape. A sensor fixing case 308 is covered on the upper part of the sensor unit 324 from above. The sensor fixing case 308 has a cylindrical shape, and in the covered state, the upper side is closed and a cable outlet 326 for taking out the cable 327 is formed, and the lower side accommodates the upper part of the sensor part 324. Is open for. In FIG. 4, the cross-sectional area S5 of the sensor fixing case 308 is larger than the cross-sectional area S6 of the sensor portion 324, and the case fixing rubber filling portion 402 is filled with rubber 318 for fixing the sensor fixing case 308. The other portions are filled with vibration preventing rubber 404 made of a material such as urethane rubber.

  In the description of the buffering agent 306, the rubber 318, and the vibration preventing rubber 404 with reference to FIGS. 3 and 4, the expressions have been changed to clarify the role of each other. Of course, as can be understood from the above description, for example, the buffering agent 306 and the vibration preventing rubber 404 may be made of the same material called urethane.

  In FIG. 3, the surface of the sample 322 is linearly described, but strictly speaking, the surface of the sample 322 may be rough. Even in such a case, measurement can be performed by bringing the sample 322 into contact.

In this way, the vibration sensor probe 302 and the reception sensor probe 304 are arranged in close proximity with the buffering prevention material 306 interposed therebetween, so that the composite sensor of the present invention has the vibration unit and the reception unit. The sensor becomes an integrated part. By using such a sensor, what was conventionally performed at two locations for excitation and reception can be completed at one location. Further , since the wave of the natural vibration of the sample can be received as it is at the place where it is vibrated , accurate measurement is possible.

  FIG. 5 is a diagram illustrating the appearance of the composite sensor 208 in FIG. Hereinafter, FIGS. 5A to 5D will be described.

  FIG. 5A is a plan view of the composite sensor 208 of FIG. As shown in FIG. 3, the cable 327 is passed through the cable outlet 326, which is a circular hole in the center, and electrical connection with other devices is made. FIG. 5B is a bottom view of the composite sensor 208 of FIG. As shown in FIG. 3, the contact portion 502 is a portion that contacts the sample when the end point portion 302 c of the excitation sensor probe 302 and the start point portion 304 c of the reception sensor probe 304 are measured. FIG. 5C is a right side view and a left side view (the reference numerals in parentheses indicate the reference numerals in the left side view). FIG. 5D is a front view and a rear view (the reference numerals in parentheses indicate the reference numerals in the rear view).

  Note that a method as shown in FIG. 6 may be used as the elastic modulus measurement method using the composite sensor in the second embodiment of the present invention. FIG. 6A shows a method of supporting a sample at two fulcrums, FIG. 6B shows a method of using one of the fulcrums supporting the sample as a composite sensor, and FIG. 6C shows a sample. This is a method of hanging one side with a composite sensor. In this case, the other line may be suspended only to fix the sample in the air.

  Further, the shape of the vibration sensor probe 302 and the reception sensor probe 304 of the composite sensor in the second embodiment of the present invention may be as shown in FIG. FIG. 7 illustrates another shape of the vibration sensor probe and the reception sensor probe of the composite sensor of the present invention. In FIG. 7A, in the vibration sensor probe 302, the cross-sectional area S71 of the start point portion 302d of the vibration sensor probe 302 is larger than the cross-sectional area S72 of the end point portion 302c, but the cross-sectional area S73 of the intermediate portion is It is larger than S71 and S72. The cross-sectional area increases from the start point 302d toward the intermediate part, and the cross-sectional seat decreases from the intermediate part toward the end point 302c. The reception sensor probe 304 has a similar shape. Thus, the intermediate shape may be unquestioned.

  Furthermore, the shape of the vibration sensor probe 302 and the reception sensor probe 304 as shown in FIG.

  Furthermore, the area relationship between the end point 302d and the start point 302c in FIG. 3 may be reversed.

  Furthermore, in the second embodiment of the present invention, a white noise signal is used as a noise signal, but a noise signal other than a white noise signal such as a pink noise signal, a flat random noise signal, or a burst noise signal may be used. Absent.

  Furthermore, the shape of the sample is not limited to a sphere or a cone.

  Next, description will be given of measurement results obtained by actually measuring the elastic modulus using the composite sensor and the elastic modulus measuring apparatus of the present invention. The sample to be measured is an amorphous amorphous material having a length of 16 cm, a thickness of 4 cm, a width of 4 cm, and a weight of 0.7 kg. The measurement method was measured using the method shown in FIG.

First, to generate a white noise signal by the white noise generator, white noise signal is given for a sample from the first filter and the composite sensor via a power amplifier which is set to 15kHz from 1 kHz. The natural vibration wave generated by the vibration of the sample is received by the composite sensor. The received wave is converted into a voltage and applied to an FFT analyzer through an amplifier and a second filter set to 1 kHz to 15 kHz.

FIG. 8 shows the output of the FFT analyzer when the sample is measured. FIG. 8A shows the frequency spectrum of white noise, and FIG. 8B shows the frequency spectrum when the sample is measured. When the sample was measured as shown in FIG. 8B, a peak of spectral intensity clearly appeared at a frequency that coincided with the natural frequency of the sample . Here, the frequency value at the peak of the spectrum intensity was 5304 Hz. When the elastic modulus was calculated by applying this frequency to the following equation, a value of 41.76 GPa could be obtained.

  Strictly speaking, the spectrum of the white noise signal is intensely vibrated up and down, but for the sake of easy understanding, it is schematically shown by a dotted line in FIG.

  In the conventional scanning method, the measurement takes 10 seconds or more. However, according to the elastic modulus measuring apparatus of the present invention, only 0.01 seconds to 0.1 seconds are required, and the measurement time is considerably shortened. I can say that.

It is the block diagram which showed an example of the structure of the elasticity measuring device in the 1st Embodiment of this invention. It is the block diagram which showed an example of the structure of the elasticity measuring device in the 2nd Embodiment of this invention. It is sectional drawing at the time of cut | disconnecting the composite sensor 208 of FIG. 2 to an up-down direction. It is sectional drawing in the IV-IV line with respect to the composite sensor 208 of FIG. It is a figure showing the state seen from the 6th surface about the external appearance of the composite sensor 208 of FIG. It is the figure which showed the other measuring method of the elasticity modulus using the composite sensor of this invention. It is the figure which illustrated the shape of the vibration sensor probe and receiving sensor probe of other compound sensors of the present invention. It is an example of the output result of the FFT analyzer 214 of FIG. It is the block which showed the structure of the apparatus regarding the technique of a nonpatent literature 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Elastic modulus measuring apparatus 101 Sample 108 Excitation sensor 110 Reception sensor

Claims (2)

A vibration means that vibrates the sample by applying a vibration wave to a sample that is a measurement object of the elastic modulus, and a reception that receives a wave of the natural vibration of the sample generated by the vibration wave provided by the vibration means. and means, an elastic modulus measuring device for calculating the modulus of elasticity of the sample on the basis of the wave of the signal of the natural frequency of the sample received by the receiving means,
The vibration wave given to the sample by the vibration means is a noise signal ,
The exciting means includes a first member extending in a direction in which a vibration wave applied to the sample propagates, and the receiving means is a direction in which a wave of the natural vibration of the sample generated by the vibration of the sample propagates. A second member extending to
The first member and the second member are arranged side by side with a cushioning material interposed therebetween,
The one end of the first member on the end side in the direction of propagation of the vibration wave propagating through the first member and the start point in the direction of propagation of the natural vibration wave of the sample propagating through the second member Each of the one end parts of the 2nd member has a contact part which contacts the said sample, The elastic modulus measuring apparatus characterized by the above-mentioned . A vibration means that vibrates the sample by applying a vibration wave to a sample that is a measurement object of the elastic modulus, and a reception that receives a wave of the natural vibration of the sample generated by the vibration wave provided by the vibration means. A compound sensor comprising:
The exciting means includes a first member extending in a direction in which a vibration wave applied to the sample propagates, and the receiving means is a direction in which a wave of the natural vibration of the sample generated by the vibration of the sample propagates. A second member extending to
The first member and the second member are arranged side by side with a cushioning material interposed therebetween,
The first member is when the size of the cross-sectional area on the start point side in the direction in which the vibration wave propagates is equal to or larger than the cross-sectional area on the end point side and the projection is performed from the start point side toward the end point side. Each cross section has a shape included in the area of the cross section on the starting point side,
The second member is projected from the end point side toward the start point side, and the cross-sectional area on the start point side in the direction in which the wave of the natural vibration of the sample propagates is equal to or less than the end point side cross-sectional area. When performed, each cross-section has a shape that falls within the area of the cross-section on the end point side,
The one end of the first member on the end side in the direction of propagation of the vibration wave propagating through the first member and the start point in the direction of propagation of the natural vibration wave of the sample propagating through the second member Each of the one end parts of the 2nd member has a contact part which contacts the said sample, The composite sensor characterized by the above-mentioned.

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