JP2008102160A - Ultrasonic measuring system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide ultrasonic measuring system which can measure with high accurately the thickness, phase change position and compositional variation states of a measuring object, even when the measuring object is small or is located in a narrow section, or is at a high temperature, such as, in a metal which is being welded. <P>SOLUTION: In this ultrasonic measuring system, ultrasonic waves are excited by an ultrasonic transmission means in a non-contact manner, in the area where the measuring object is located, then the ultrasonic waves that passed through the measuring object are detected by an ultrasonic receiving means. In addition, a propagation time measuring means measures the propagation time of the ultrasonic waves, from the time difference between the transmission time of the ultrasonic waves and the reception time of the ultrasonic waves. A velocity calibration means calibrates the propagation velocity of the ultrasonic waves in the measuring object from the temperature or the temperature distribution of the measuring object measured by temperature measuring means; while a propagation path length measuring means computes the propagation path length of the ultrasonic waves, from both the propagation time measured by the propagation time measuring means and the sound wave velocity obtained by the velocity calibration means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic measurement device that uses ultrasonic waves to measure the thickness of a medium to be measured, the boundary position of a phase change in the depth direction, and the composition state in the depth direction.

  In general, an ultrasonic echo method as shown in FIG. 15 is known as a measurement method for measuring information in the depth direction of a measurement target. In this ultrasonic echo method, information in the depth direction of the measurement target is measured as follows. For simplicity, the case where the measurement object 1 is a solid will be described here.

  First, the ultrasonic probe 3 is brought into contact with the measurement object 1 through the coplant 2. In this state, an electrical signal is applied from the transmitter 4 to the ultrasonic probe 3, and the ultrasonic wave 5 is transmitted from the ultrasonic probe 3 into the measurement object 1. The transmitted ultrasonic wave 5 propagates through the measurement object 1, is reflected on the back surface, and is reflected again in the vicinity of the ultrasonic probe 3. This reflected wave is received by the ultrasonic probe 3, converted into an electric signal by the reverse action of transmission, and input to the signal detector 6. The transmission signal from the transmitter 4 is also input to the signal detector 6, and the ultrasonic wave 5 passes through the time difference Δt between the reception time of the transmission signal and the reception time of the reception signal in the signal detector 6, that is, in the measurement object 1. Propagated time is measured.

  Here, the propagation velocity vs of the ultrasonic wave transmitted through the measurement object 1 is input to the signal detector 6 in advance, and the thickness d of the measurement object 1 is determined from the measured time difference Δt and the ultrasonic wave propagation speed vs. It is calculated from the relationship of equation (1).

d = vs · Δt / 2 (1)
In the example of FIG. 15, it is assumed that the measurement target 1 is a uniform solid phase. However, when a part of the measurement target 1 is melted and exhibits the liquid phase 7, as shown in FIG. Both the reflected wave 9 generated in the boundary region between the solid phase 8 and the liquid phase 7 and the reflected wave 10 generated on the liquid phase surface, that is, the back surface of the measurement object 1 are measured.

  On the other hand, as a non-contact ultrasonic transmission method, for example, there is a technique using laser light. This is because when a short pulse high energy laser beam is irradiated onto a certain control target 1, thermal stress or vaporization (ablation) compression force is generated near the irradiation point due to absorption of the laser energy, and distortion due to the action becomes ultrasonic waves. It is a technique of propagating through the subject. This method is theoretically and experimentally clarified by J. D. Aussel ("Generation Acoustic Waves by Laser: Theoretical and Experimental Study of the Emission Source," Ultrasonics, vol. 24 (1988), 246-255).

  As a method for controlling the propagation direction (directivity) of ultrasonic waves generated by laser light, for example, a method using an optical fiber is described in J. Jarzynski ("The Use of Optical Fibers to Enhance the Laser Generation of Ultrasonic Waves," Journalof The Acoustical Society of America, Vol. 85 (1989), 158-162) et al., and RFIng ("Focusing and Beamsteering of Laser Generated Ultrasound," IEEE-1989 Ultrasonics Symposium, 539-544) Et al.

  Further, as a non-contact ultrasonic receiving means, for example, there is a technique using laser light. This is to measure the minute vibration that occurs when the ultrasonic wave reaches the surface to be measured from the change (deflection) of the traveling direction of the laser light, the phase difference of the reflected light, the frequency transition amount, etc. "Laser ultrasonic and non-contact material evaluation," explained by Journal of the Japan Welding Society, Vol. 64 (1995), 104-108). In addition, the composition state inside the measurement object 1, for example, the distribution of grain boundary dimensions in a solid sample, is currently microscopically observed by destroying the sample and etching the cross section.

  However, the above-described measurement method using the ultrasonic probe 3 is a simple depth direction information measuring means and is effective for a normal measurement target, but the ultrasonic probe 3 is installed. In some cases, it is necessary to apply coplanar, which leads to an increase in the number of work processes. Moreover, when the measurement object 1 is small or in a narrow part, it is difficult to install the ultrasonic probe 3.

  Further, when the object 1 to be measured is a high temperature such as a metal being welded, a special mechanism for preventing damage due to evaporation of the coplanar 2 and the temperature of the ultrasonic probe 3 is required, and the temperature or temperature gradient of the medium is required. Changes the propagation speed of ultrasonic waves, making accurate measurement difficult. Moreover, the composition state measurement method inside the measurement target 1 by the above-described destruction method cannot be performed on the device in use due to the method.

  The object of the present invention is to accurately measure the thickness of the measurement object, the position of the phase change, and the state of the composition change even when the measurement object is small or in a narrow part or at a high temperature such as a metal being welded. It is to provide an ultrasonic measurement device capable of measuring.

  The ultrasonic measurement apparatus according to the invention of claim 1 is an ultrasonic transmission means for exciting an ultrasonic wave in a non-contact manner to a portion of the measurement object, and an ultrasonic wave for detecting the ultrasonic wave propagated in the measurement object in a non-contact manner. A sound wave receiving means, and a propagation time measuring means for measuring a propagation time of the ultrasonic wave from a time difference between a transmission time when the ultrasonic wave is transmitted by the ultrasonic wave transmitting means and a reception time when the ultrasonic wave receiving means receives the ultrasonic wave. Temperature measurement means for measuring the temperature or temperature distribution of the measurement object, and the temperature distribution inside the measurement object along the propagation direction of ultrasonic waves from the surface temperature or surface temperature distribution measured by the temperature measurement means. A temperature distribution estimator to be estimated, a speed calibration means for calibrating the propagation speed of the ultrasonic wave propagating through the measurement object from the temperature distribution estimated by the temperature distribution estimator, and a transmission measured by the propagation time measurement means. It is obtained by and a propagation path length measuring means for calculating a propagation path length of the ultrasonic wave from the propagation velocity obtained by time and the speed calibration means.

  In the ultrasonic measuring apparatus according to the first aspect of the present invention, ultrasonic waves are excited from the ultrasonic transmission means in a non-contact manner to a certain part of the measurement target, and the ultrasonic waves propagated in the measurement target are contactlessly transmitted by the ultrasonic reception means. To detect. Then, the propagation time measuring means measures the propagation time of the ultrasonic wave from the time difference between the transmission time when the ultrasonic wave is transmitted from the ultrasonic wave transmitting means and the reception time when the ultrasonic wave receiving means receives the ultrasonic wave. The velocity calibration means calibrates the ultrasonic propagation velocity in the measurement object from the temperature or temperature distribution of the measurement object measured by the temperature measurement means, and the propagation path length measurement means calibrates the propagation time and velocity measured by the propagation time measurement means. The propagation path length of the ultrasonic wave is calculated from the propagation speed obtained by the calibration means. Thereby, the thickness of the measuring object is detected.

  An ultrasonic measurement apparatus according to a second aspect of the present invention includes an ultrasonic transmission unit that excites an ultrasonic wave in a non-contact manner on a portion of a measurement target, and an acoustic characteristic of the ultrasonic wave that has propagated through the measurement target on a propagation path. Ultrasonic wave receiving means for detecting a reflected wave generated by being reflected by a change area in a non-contact manner, a transmission time when the ultrasonic wave is transmitted by the ultrasonic wave transmitting means, and a reception time when the ultrasonic wave receiving means receives the reflected wave Propagation time measuring means for measuring the propagation time of the ultrasonic wave from the time difference with time, temperature measuring means for measuring the temperature or temperature distribution of the measurement object, and surface temperature or surface temperature distribution measured by the temperature measuring means A temperature distribution estimator for estimating the internal temperature distribution of the measurement target along the propagation direction of the ultrasonic wave from, and the propagation speed of the ultrasonic wave propagating in the measurement target from the temperature distribution estimated by the temperature distribution estimation unit Speed calibration means for calibrating, and propagation path length measurement means for calculating the propagation path length of the ultrasonic wave from the propagation time measured by the propagation time measurement means and the propagation speed obtained by the speed calibration means. is there.

  In the ultrasonic measuring apparatus according to the second aspect of the present invention, the ultrasonic wave is excited from the ultrasonic wave transmitting means in a non-contact manner on a portion of the measurement target, and the ultrasonic wave propagating through the measurement target is an acoustic characteristic changing region on the propagation path. The reflected wave generated by the reflection is detected by the ultrasonic wave receiving means in a non-contact manner. The propagation time measuring means measures the propagation time of the ultrasonic wave from the time difference between the transmission time when the ultrasonic wave is transmitted by the ultrasonic wave transmitting means and the reception time when the ultrasonic wave receiving means receives the reflected wave. The propagation speed of the ultrasonic wave in the measuring object is calibrated from the temperature or temperature distribution of the measuring object measured by the temperature measuring means. The propagation path length measurement means calculates the propagation path length of the ultrasonic wave from the propagation time measured by the propagation time measurement means and the propagation speed obtained by the speed calibration means. Thereby, the thickness of the acoustic characteristic changing region is detected.

  An ultrasonic measurement apparatus according to a third aspect of the invention is the ultrasonic measurement apparatus according to the first or second aspect, wherein the ultrasonic wave is excited with respect to the measurement object by the ultrasonic transmission means or the ultrasonic wave is advanced. Transmission position scanning means for arbitrarily driving the direction, reception position scanning means for arbitrarily driving the detection position of the ultrasonic wave or reflected wave ultrasonic wave propagation means through the measurement object, and transmission position scanning Recording means for inputting the position information from the receiving means and the receiving position scanning means and recording the output signal of the propagation path length measuring means in each positional relationship in association with the position information, and the number of information recorded in the recording means Alternatively, display means for displaying as a graph or an image is provided.

  In the ultrasonic measuring apparatus according to the third aspect of the invention, in addition to the operation of the ultrasonic measuring apparatus according to the first or second aspect, the transmission position scanning means is an ultrasonic transmission means for the measurement object. The reception position scanning unit arbitrarily drives the detection position of the ultrasonic wave or reflected wave that has propagated through the measurement object. Then, the recording means inputs the position information from the transmission position scanning means and the reception position scanning means, and records the output signal of the propagation path length measuring means in each positional relationship in association with the position information. The display means displays the information recorded in the recording means as a numerical table, a graph, or an image.

  An ultrasonic measurement apparatus according to a fourth aspect of the present invention is the ultrasonic measurement apparatus according to the first or second aspect, wherein the measurement object is for driving the position of the measurement object relative to the ultrasonic transmission means and the ultrasonic reception means. The position information is input from the position scanning means, the measurement target position scanning means, and the output signal of the propagation path length measuring means in each positional relationship is recorded in association with the position information, and recorded in the recording means And display means for displaying information as a numerical table, a graph, or an image.

  In the ultrasonic measurement apparatus according to the invention of claim 4, in addition to the operation of the ultrasonic measurement apparatus according to claim 1 or 2, the measurement target position scanning means includes an ultrasonic transmission means and an ultrasonic reception of the measurement object. The position with respect to the means is driven, and the recording means inputs the position information from the measurement target position scanning means, and records the output signal of the propagation path length measuring means in each positional relationship in association with the position information. The display means displays the information recorded in the recording means as a numerical table, a graph, or an image.

  An ultrasonic measurement apparatus according to a fifth aspect of the present invention includes an ultrasonic transmission unit that excites an ultrasonic wave in a non-contact manner on a portion of the measurement target, and an acoustic characteristic on the propagation path of the ultrasonic wave that has propagated through the measurement target. Ultrasonic wave receiving means for detecting non-contact ultrasonic waves reflected, scattered, diffracted or transmitted in the change region, temperature measuring means for measuring the temperature or temperature distribution of the measurement object, and the surface measured by the temperature measuring means A temperature distribution estimation unit that estimates the temperature distribution inside the measurement target along the propagation direction of the ultrasonic wave from the temperature or surface temperature distribution, and propagates through the measurement target from the temperature distribution estimated by the temperature distribution estimation unit. A speed calibration means for calibrating the propagation speed of ultrasonic waves and a signal received by the ultrasonic reception means in consideration of the propagation speed required by the speed calibration means are compared with a reference signal prepared in advance. A signal waveform evaluation unit that is obtained by including a propagation path diagnosing section for diagnosing the state of the ultrasonic wave propagation path from the evaluation results of the signal waveform evaluation unit.

  In the ultrasonic measurement apparatus according to the invention of claim 5, the ultrasonic wave is excited from the ultrasonic transmission means in a non-contact manner on a part of the measurement target, and the ultrasonic wave propagating through the measurement target is an acoustic characteristic changing region on the propagation path. The ultrasonic wave reflected, scattered, diffracted or transmitted by is detected in a non-contact manner by the ultrasonic wave receiving means. Then, the ultrasonic wave propagation speed in the measurement object is calibrated by the speed calibration means from the temperature or temperature distribution of the measurement object measured by the temperature measurement means, and the signal wave evaluation means considers the propagation speed required by the speed calibration means. Then, the signal received by the ultrasonic wave receiving means is compared with a reference signal prepared in advance, and the propagation path diagnosis means diagnoses the state of the ultrasonic wave propagation path from the evaluation result of the signal waveform evaluation means.

  The ultrasonic measurement apparatus according to a sixth aspect of the invention is the ultrasonic measurement apparatus according to the fifth aspect, wherein the physical quantity to be compared between the reference signal and the reception signal in the signal waveform evaluation means is a signal level or frequency. The spectrum or phase or pulse width or propagation time or decay rate, or a combination of these physical quantities.

  In the ultrasonic measurement apparatus according to the invention of claim 6, in addition to the action of the ultrasonic measurement apparatus of claim 5, the signal waveform evaluation means includes a signal level, frequency spectrum, phase, pulse width, propagation time, or attenuation. The rate or a plurality of combinations of these physical quantities are compared with the reference signal.

  An ultrasonic measurement apparatus according to a seventh aspect of the invention is the ultrasonic measurement apparatus according to the fifth or sixth aspect, wherein a position at which an ultrasonic wave is excited by an ultrasonic wave transmission means with respect to a measurement object or the progress of the ultrasonic wave Transmission position scanning means for arbitrarily driving the direction, reception position scanning means for arbitrarily driving the detection position of the ultrasonic wave propagating through the measurement object, transmission position scanning means and reception Recording means for inputting the position information from the position scanning means and recording the output information of the propagation path diagnosis means in each positional relationship in association with the position information, and the information recorded in the recording means as a numerical table, graph or image As a display means.

  In the ultrasonic measuring apparatus according to the seventh aspect of the invention, in addition to the operation of the ultrasonic measuring apparatus according to the fifth or sixth aspect, the transmission position scanning means is an ultrasonic transmission means for the measurement object. The receiving position scanning unit arbitrarily drives the detection position of the ultrasonic wave propagating through the measurement target by the ultrasonic wave receiving unit. The recording means inputs the position information from the transmission position scanning means and the reception position scanning means, records the output information of the propagation path diagnosis means in each positional relationship in association with the position information, and the display means records The information recorded in the means is displayed as a numerical table, a graph or an image.

  An ultrasonic measurement apparatus according to an eighth aspect of the present invention is the ultrasonic measurement apparatus according to the fifth or sixth aspect, wherein the measurement target is for driving the position of the measurement target relative to the ultrasonic transmission means and the ultrasonic reception means. The position scanning means, the recording means for inputting the position information from the measurement target position scanning means and recording the output information of the propagation path diagnosis means in each positional relationship in association with the position information, and the information recorded in the recording means And display means for displaying as a numerical table, a graph, or an image.

  In the ultrasonic measurement apparatus according to the invention of claim 8, in addition to the action of the ultrasonic measurement apparatus according to claim 5 or 6, the measurement position scanning means includes an ultrasonic transmission means and an ultrasonic reception means to be measured. The recording means inputs the position information from the measurement target position scanning means, records the output information of the propagation path diagnosis means in each positional relationship in association with the position information, and the display means records the recording means. The information recorded in is displayed as a number table, graph or image.

  An ultrasonic measuring apparatus according to a ninth aspect of the present invention is the ultrasonic measuring apparatus according to any one of the first to fourth aspects, wherein the ultrasonic transmitting means is laser light that is intermittent or modulated in time. A laser focused spatially in the form of dots, circles, ellipses, lines, concentric circles, dots, or grids up to the energy density necessary and sufficient to generate thermal strain or ablation on the surface to be measured It uses light.

  In the ultrasonic measuring apparatus according to the ninth aspect of the invention, in addition to the action of the ultrasonic measuring apparatus according to the first to fourth aspects, the ultrasonic transmitting means may be a temporally intermittent or modulated wave laser. Light is transmitted. In addition, this laser beam has an energy density necessary and sufficient to generate thermal strain or ablation on the surface to be measured, and is spatially dotted, circular, elliptical, linear, concentric, or dotted. Alternatively, the light is condensed and irradiated in a lattice shape.

  The ultrasonic measurement apparatus according to the invention of claim 10 is the ultrasonic measurement apparatus according to claim 9, wherein the laser beam used as the ultrasonic transmission means is guided from the light source to the vicinity of the irradiation position on the measurement object by the optical fiber. It is what I did.

  In the ultrasonic measurement apparatus according to the invention of claim 10, in addition to the action of the ultrasonic measurement apparatus according to claim 9, the laser light from the ultrasonic transmission means is transmitted from the light source to the vicinity of the irradiation position on the measurement object by an optical fiber. Led.

  The ultrasonic measurement apparatus according to the invention of claim 11 is the ultrasonic measurement apparatus according to any one of claims 1 to 4, wherein the ultrasonic reception means uses an interference phenomenon or a deflection phenomenon of laser light. It is what I did.

  In the ultrasonic measuring apparatus according to the invention of claim 11, in addition to the operation of the ultrasonic measuring apparatus according to claims 1 to 4, the ultrasonic receiving means uses an interference phenomenon or a deflection phenomenon of laser light. Sound wave detection is performed.

  An ultrasonic measurement apparatus according to a twelfth aspect of the present invention is the ultrasonic measurement apparatus according to the eleventh aspect, wherein the laser beam used as the ultrasonic wave receiving means is guided from the light source to the vicinity of the detection irradiation position on the measurement object by an optical fiber. In addition, the reflected light is guided to the interference mechanism or the deflection detection mechanism by the same or different optical fiber.

  In the ultrasonic measurement apparatus according to the invention of claim 12, in addition to the action of the ultrasonic measurement apparatus of claim 11, the laser light used in the ultrasonic reception means is detected from the light source to the detection irradiation position on the measurement object by the optical fiber. The light is guided to the vicinity, and the reflected light is guided to the interference mechanism or the deflection detection mechanism by the same or different optical fiber.

  An ultrasonic measurement apparatus according to a thirteenth aspect of the present invention is the ultrasonic measurement apparatus according to any one of the ninth to twelfth aspects, wherein the ultrasonic transmission point by the laser light of the ultrasonic transmission means and the laser light of the ultrasonic reception means. Is provided with a shielding plate between the ultrasonic wave receiving points.

  In the ultrasonic measuring apparatus according to the thirteenth aspect of the invention, in addition to the action of the ultrasonic measuring apparatus according to the ninth to twelfth aspects, disturbance due to reflected light or scattered light generated on the surface of the measurement object by the shielding plate is prevented. Can be prevented.

  As described above, according to the present invention, it is possible to simplify the work process of application of coplanar and contact installation of an ultrasonic probe, and the measurement target is small or in a narrow part or the measurement target. Even when the temperature is high, such as during welding, it is possible to correct changes in the propagation speed of the ultrasonic wave due to the temperature of the medium or temperature gradient, and accurately measure the thickness of the measurement target, the position of the phase change, and the state of the composition change. It becomes possible.

  In other words, when measuring the thickness of a medium or the boundary position of a phase change in the depth direction or the composition state in the depth direction using ultrasonic waves, calibration is performed using the temperature or temperature distribution information of the medium. The measurement accuracy can be improved. It is also possible to measure the thickness of objects to be measured that are difficult to contact or access, such as small or high temperature or narrow areas, or the three-dimensional penetration shape of the metal base material and filler metal during welding, or the heat inside the metal after welding. The distribution of the affected part can be detected with high accuracy without contact and without destruction.

  Embodiments of the present invention will be described below. FIG. 1 is a configuration diagram of an ultrasonic measurement apparatus according to the first embodiment of the present invention.

  The ultrasonic measurement apparatus according to the first embodiment includes an ultrasonic transmission unit 11 that excites an ultrasonic wave 5 in a non-contact manner on a surface of the measurement target 1, and a propagation path of the ultrasonic wave 5 that has propagated through the measurement target 1. Ultrasonic wave receiving means 12 for detecting the reflected waves 9 and 10 reflected by the upper acoustic characteristic changing region in a non-contact manner, a transmission time t0 at which the ultrasonic wave 5 is transmitted by the ultrasonic wave transmitting means 11, and ultrasonic wave reception The propagation time measuring means 13 for measuring the propagation time Δt of the ultrasonic wave 5 from the difference between the reception times tr when the means 12 receives the reflected waves 9 and 10, and the temperature of the ultrasonic excitation surface of the measurement object 1 or its back surface, or Temperature measuring means 14 for measuring both temperatures, speed calibration means 15 for calibrating the ultrasonic propagation velocity vs (T) in the measuring object 1 from the temperature T measured by the temperature measuring means 14, and propagation time measuring means 13 Propagation time measured at And a propagation path length measuring means 16 for calculating the propagation path length out1 of the ultrasonic wave 5 from the propagation speed vs (T) obtained by the speed calibration means 15.

  In FIG. 1, the ultrasonic wave 5 is transmitted to the measurement object 1 from the ultrasonic wave transmission means 11 without contact and with directivity in the depth direction of the measurement object 1. The transmitted ultrasonic wave 5 propagates through the measurement object 1 and is reflected by the boundary region between the solid phase 8 and the liquid phase 7 in the measurement object 1 and the liquid phase surface, that is, the back surface of the measurement object 1, and from each position. A reflected wave 9 and a reflected wave 10 are generated. These reflected waves 9 and 10 are detected by the ultrasonic detection means 12 in a non-contact manner.

  Here, the ultrasonic transmission means 11 outputs laser light that is irradiated intermittently or in a modulated wave with respect to time. Then, up to the energy density necessary and sufficient to generate thermal strain or ablation on the surface of the measuring object 1, it is spatially collected in the form of dots, circles, ellipses, lines, concentric circles, dots, or grids. The emitted laser beam is output. Further, the ultrasonic wave detection by the ultrasonic wave receiving means 12 is performed by using a laser beam interference phenomenon or a laser beam deflection phenomenon.

  An example of a detection waveform when laser light is used for the non-contact ultrasonic transmission unit 11 and the ultrasonic reception unit 12 is shown in FIG. In FIG. 2, the time t0 is the oscillation time of the laser beam for transmission, the time tr9 is the reception time of the ultrasonic wave 9 reflected from the boundary between the solid phase 8 and the liquid phase 7, and the time tr10 is reflected from the back surface of the measurement object. It is the reception time of the ultrasonic wave 10.

  When ultrasonic transmission / reception is performed using laser light, the propagation speed of the light is extremely high compared to the propagation speed of the ultrasonic wave. Therefore, the time t0 when the laser light oscillates in the ultrasonic transmission means 11 is the ultrasonic wave. The time when 5 is excited on the surface of the measurement object 1 and the time tr when the laser interferometer or laser deflectometer in the ultrasonic wave receiving means 12 detects the ultrasonic wave, that is, the reflected waves 9 and 10 reach the surface of the measurement object 1. Can be treated as time.

  The propagation time measuring means 13 measures a time difference Δt9 and a time Δt10 between the time t0, the time tr9, and the time tr10. Here, if the ultrasonic wave propagation velocity vs and the liquid phase 7 propagation velocity vL transmitted through the solid phase 8 are known, the thickness ds of the solid phase 8 and the liquid in the measurement object 1 using the relationship of the equation (1). Each thickness dL of phase 7 can be determined. Here, the propagation time measuring means 13 converts a reflected basic ultrasonic waveform prepared in advance into an arbitrary signal waveform that can specify the generation time for each of the reflected waves 9 and 10, and this signal. A reception time measuring function for measuring the reception time of each reflected wave from the converted signal obtained by converting the reception signal of the ultrasonic wave receiving means 12 into an arbitrary signal waveform capable of specifying the generation time corresponding to the number of reflected waves by the conversion function. And a time difference detection function for detecting a time difference between the transmission time t0 and the reception times tr9 and tr10. The propagation time is obtained by these functions.

  Next, it is known that the speed of ultrasonic waves in a medium depends on the temperature of the medium. As an example, a graph showing the temperature dependence of the propagation speed of ultrasonic waves in Armco iron is shown in FIG. As shown in FIG. 3, the sound velocity vs and the sound velocity vL of the ultrasonic wave greatly vary depending on the temperature of the medium. If this is not taken into account, the measurement accuracy is deteriorated due to an error in thickness measurement. Therefore, the thickness measurement accuracy is improved by measuring the temperature of the front and back surfaces of the measuring object 1 with the temperature measuring means 14 and calibrating the propagation speed based on the relationship between the temperature and the propagation speed previously obtained as shown in FIG.

  When the distance L between the ultrasonic transmission position pe by the ultrasonic transmission means 11 and the ultrasonic reception position pr by the ultrasonic reception means 12 is sufficiently smaller than the thickness d of the measurement target 1. The thickness d is obtained by the equation (1) considering the temperature dependence of the sound speed. However, when L is not negligible compared with d, the thickness is obtained by the following equation (2) as shown in FIG. d is obtained.

  In such a case, in the ultrasonic transmission means 11, as described in the prior art, a propagation directivity of a desired angle θ is given to the ultrasonic wave 5 transmitted using an optical fiber or the Bragg diffraction effect, If a function for searching for a measurement point where the ultrasonic level that can be detected is maximized is provided in the sound wave receiving means 12, signal detection becomes easier.

  As shown in FIG. 5, when there is no phase change such as the liquid phase 7 and the solid phase 8 (when measuring the thickness of the simple measurement object 1), the ultrasonic transmission means 11 and the ultrasonic reception means 12 are used. Are arranged on opposite surfaces, and the transmitted ultrasonic wave 5 is measured.

  As described above, according to the first embodiment, the non-contact ultrasonic transmission unit 11 and the ultrasonic reception unit 12 using laser light or the like are provided, so that the work process can be shortened and the measurement medium can be sized and arranged. In addition to enabling measurement independent of the temperature, the velocity calibration unit 15 calibrates the propagation speed of the ultrasonic wave in the medium from the temperature or temperature distribution information of the medium from the temperature measurement unit 14 to improve the accuracy of the measurement value. It becomes possible.

  Here, in the above description, the reflected waves 9 and 10 reflected at the boundary of the phase change between the ultrasonic wave 5 or the liquid phase 7 or the liquid phase 8 and the solid phase 8 propagated through the measurement object 1 are detected without contact. These thicknesses are detected, but the reflected wave generated by the ultrasonic wave propagating through the measurement target 1 being reflected by the acoustic characteristic change region on the propagation path is detected in a non-contact manner, and the measurement target 1 is detected. The thickness (acoustic characteristic change region) may be detected.

  That is, it is known that the metal characteristics during the welding or after the welding changes in the size of the metal crystal grains due to melting, and the acoustic characteristics such as acoustic impedance change. Are detected without contact and their thickness is detected. In this case, the same effect as that of the first embodiment can be obtained.

  Next, a second embodiment of the present invention will be described. FIG. 6 is a configuration diagram of an ultrasonic measurement apparatus according to the second embodiment of the present invention. This second embodiment differs from the first embodiment shown in FIG. 1 in a two-dimensional position that does not include the depth direction in which the ultrasonic wave transmission means 11 for the measurement target 1 excites the ultrasonic wave 5. Or the transmission position scanning means 17 for arbitrarily driving the traveling direction of the ultrasonic wave 5 and the depth direction of the ultrasonic wave 5 or reflected waves 9 and 10 propagated through the measurement object 1 by the ultrasonic wave receiving means 12 are included. The position information out2 is input from the receiving position scanning means 18, the transmission position scanning means 17 and the receiving position scanning means 18 for arbitrarily driving a non-two-dimensional detection position, and the propagation path length measurement in each positional relationship is performed. Recording means 19 for recording the output signal out1 of the means 16 in association with the position information out2, and display means 20 for displaying the information recorded in the recording means 19 as a numerical table, a graph or an image are added. It is those provided. Thereby, the distribution shape of the liquid phase 7 is measured.

  Further, a mechanism for two-dimensionally scanning the measurement target 1 not including its depth direction while the transmission position and reception position of the ultrasonic waves in the transmission position scanning unit 17 and the reception position scanning unit 18 are fixed, that is, the measurement target position Similarly, the distribution shape of the liquid phase 7 can be measured by providing scanning means.

  In FIG. 6, a transmission position scanning means 17 is provided to allow the ultrasonic transmission means 11 to arbitrarily determine the transmission position pe of the ultrasonic wave 5, and a reception position scanning means 18 is provided to receive the ultrasonic wave 5 by the ultrasonic wave reception / transmission means 12. The position pr can be arbitrarily determined. Thereby, thickness information ds and dL at each position is obtained. Therefore, the two-dimensional distribution of the boundary position between the solid phase 8 and the liquid phase 7 or the three-dimensional shape of each of the solid phase 8 and the liquid phase 7 can be measured. Thereby, when the thickness of the liquid phase 7 or the solid phase 8 is not uniform, the distribution shape of the thickness of the liquid phase 7 or the solid phase 8 can be measured.

  As described above, according to the second embodiment, the non-contact ultrasonic transmission unit 11 and the ultrasonic reception unit 12 are used, and the transmission position scanning unit 17 and the reception position scanning unit 18 are used. Since the ultrasonic transmission position or transmission direction relative to the medium of the measurement object 1 and the ultrasonic reception position are both scanned two-dimensionally, the shape of the medium or phase change region can be reconstructed three-dimensionally. .

  Next, a third embodiment of the present invention will be described. FIG. 7 is a configuration diagram of an ultrasonic measurement apparatus according to the third embodiment of the present invention. In the third embodiment, the state of the acoustic characteristic change region 21 on the ultrasonic wave propagation path, for example, the thickness and the extent of the part where melting or thermal influence occurs can be measured.

  The ultrasonic measurement apparatus according to the third embodiment includes an ultrasonic transmission unit 11 that excites the ultrasonic wave 5 in a non-contact manner on a surface of the measurement object 1, an ultrasonic wave 5 that propagates through the measurement object 1, and an ultrasonic wave. 5 is an ultrasonic receiving means 12 for detecting the ultrasonic waves 22 and 23 reflected, scattered, diffracted and transmitted in the acoustic characteristic changing region 21 on the propagation path in a non-contact manner; and a temperature measuring means 14 for measuring the temperature of the measuring object 1. Then, the speed calibration means 15 for calibrating the ultrasonic propagation velocity vs (T) in the measurement object 1 from the temperature T measured by the temperature measurement means 14, and the speed calibration means 15 for receiving the signal received by the ultrasonic reception means 12. A signal waveform evaluation means 25 for comparing with a reference signal prepared in advance in the database 24 in consideration of the required propagation speed, and a propagation path for diagnosing the ultrasonic propagation path state out3 from the evaluation result of the signal waveform evaluation means 25 Composed of cross section 26.. Thereby, the state of the acoustic characteristic change region 21 on the propagation path is measured.

  In FIG. 7, ultrasonic waves are transmitted to the measurement target 1 from the ultrasonic transmission unit 11 in a non-contact manner and with directivity in the depth direction of the measurement target 1. The transmitted ultrasonic wave 5 propagates through the measurement object 1 and reaches the acoustic characteristic change region 21 in the measurement object 1. For example, it is known that in a metal during or after welding, a change in size of metal crystal grains accompanying melting occurs, and acoustic characteristics such as acoustic impedance change. The behavior of the ultrasonic wave 5 in this region is as follows.

  That is, when the crystal grain scale is sufficiently smaller than the wavelength of the ultrasonic wave 5 (such as a metal before welding) (acoustic characteristics are not changed), the ultrasonic wave 5 and the crystal grain do not interact with each other. Passes straight through. On the other hand, when the crystal grain scale is not negligible compared to the wavelength of the ultrasonic wave 5 (acoustic characteristics are changed), the ultrasonic wave 5 interacts with the crystal grain, and the ultrasonic wave 5 is reflected, scattered, diffracted, etc. A phenomenon occurs. In the former case, the transmitted ultrasonic wave propagates and is detected with almost the same waveform shape, whereas in the latter case, micro reflection at the grain interface at each point of the propagation path and small angle scattering by the metal grain boundary. Transmission ultrasonic waves are detected in different waveform shapes due to the influence of attenuation of level, increase of pulse width, phase delay, broadening of frequency spectrum, increase of propagation time, etc. .

  These ultrasonic waves 22 and 23 are detected by the ultrasonic detection means 12 as non-contact time-series signal changes. Further, the temperature of the front surface and the back surface of the sample is measured by the temperature measuring means 14, and the measurement waveform obtained by calibrating the propagation speed is input to the signal waveform evaluating means 25. The signal waveform evaluation means 25 compares the measured waveform with pre-recorded waveform data (reference signal), and outputs it from the propagation path diagnosis means 26 as information on the thickness and the extent of the site where melting or thermal influence occurs. .

  Here, the waveform data not passing through the acoustic characteristic change region 21 is recorded in the database 24 in advance. This waveform data can be collected by, for example, measuring the same sample before welding with the same apparatus in advance, and heat effects and melting due to welding do not occur during or after welding. The part may be collected using the same or different device. Alternatively, the transmission waveform itself may be recorded as waveform data by some method. That is, the database 24 stores reference signals of signal levels, frequency spectra, phases, pulse widths, propagation times, attenuation rates, or a plurality of combinations of these physical quantities.

  As described above, according to the third embodiment, the composition state in the depth direction of a certain medium is measured from the change in the time-series signal of the ultrasonic wave that has propagated through the region. The internal composition state can be evaluated.

  Next, a fourth embodiment of the present invention will be described. FIG. 8 is a block diagram of an ultrasonic measurement apparatus according to the fourth embodiment of the present invention. In the fourth embodiment, the distribution shape of the acoustic characteristic change region 21 is measured with respect to the third embodiment shown in FIG.

  That is, a transmission position scanning unit 17 for arbitrarily driving a two-dimensional position that does not include a depth direction in which the ultrasonic wave 5 is excited by the ultrasonic wave transmission unit 11 for the measurement target 1 or a traveling direction of the ultrasonic wave 5; A reception position scanning means 18 for arbitrarily driving a two-dimensional detection position not including the depth direction by the ultrasonic wave reception means 12 of the ultrasonic waves 5, 22, and 23 propagated through the measurement object 1; and a transmission position The position information out2 is input from the scanning means 17 and the reception position scanning means 18, and the output signal out3 of the propagation path diagnosis means 26 in each positional relationship is recorded in association with the position information out2. A display means 20 for displaying the recorded information as a numerical table, a graph, or an image is additionally provided. Thereby, the distribution shape of the acoustic characteristic change region 21 is measured. That is, when the thickness of the acoustic characteristic change region 21 is not uniform, the thickness distribution shape of the acoustic characteristic change region 21 can be measured.

  Further, a measurement target position scanning unit that scans the measurement target 1 two-dimensionally without including the depth direction while the transmission position and the reception position of the ultrasonic waves in the transmission position scanning unit 17 and the reception position scanning unit 18 are fixed. The distribution shape of the acoustic characteristic change region 21 can be similarly measured by providing the same.

  In FIG. 8, the transmission position scanning means 17 is provided to allow the ultrasonic transmission means 11 to arbitrarily determine the transmission position pe of the ultrasonic wave 5, and the reception position scanning means 18 is provided to receive the ultrasonic wave 5 by the ultrasonic wave reception / transmission means 12. The position pr can be arbitrarily determined. Thereby, the propagation path information at each position is obtained. Accordingly, it is possible to measure a two-dimensional distribution or a three-dimensional shape of the acoustic characteristic change region 21, and when the thickness of the acoustic characteristic change region 21 is not uniform, The thickness distribution shape can be measured.

  As described above, according to the fourth embodiment, by using the non-contact ultrasonic transmission unit 11 and the ultrasonic reception unit 12, and using the transmission position scanning unit 17 and the reception position scanning unit 18, Since both the ultrasonic transmission position or transmission direction relative to the medium of the measurement object 1 and the ultrasonic reception position are scanned two-dimensionally, the composition state inside the medium can be reconstructed three-dimensionally.

  Next, a fifth embodiment of the present invention will be described. FIG. 9 is an explanatory diagram of an ultrasonic measurement apparatus according to the ninth embodiment of the present invention. In the fifth embodiment, information in the thickness direction related to the phase change 7 (or acoustic characteristic change region 21) in the measurement target 1 is measured from the temperature distribution.

  In FIG. 9, the ultrasonic transmission means 11 that excites the ultrasonic wave 5 in a non-contact manner on a surface of the measurement target 1 and the liquid phase 7 (or change in acoustic characteristics) on the propagation path of the ultrasonic wave 5 that has propagated through the measurement target 1. The ultrasonic wave receiving means 12 for detecting the ultrasonic waves 9 and 10 reflected by the region 21) or the scattered, diffracted and transmitted ultrasonic waves 22 and 23 in a non-contact manner, and the ultrasonic wave transmitting means 11 transmit the ultrasonic waves 5 The propagation time measuring means 13 for measuring the propagation time Δt of the ultrasonic wave from the time difference between the transmitted time t0 and the reception time tr when the ultrasonic wave receiving means 12 received the reflected waves 9, 10 (or the ultrasonic waves 22, 23); From the temperature measuring means 14 for measuring the temperature of the measuring object 1, the temperature measured by the temperature measuring means 14, the propagation time Δt measured by the propagation time measuring means 13, and the thickness data of the measuring object 1 prepared in the database 27 in advance. Measurement target 1 includes temperature distribution estimation means 28 for estimating the temperature distribution state out4 along the propagation path of the ultrasonic wave 5 inside. Thereby, the information of the thickness direction regarding the phase change 7 (or acoustic characteristic change area | region 21) in the measuring object 1 is measured from the temperature distribution.

  When the ultrasonic wave transmission means 11 excites the ultrasonic wave 5 in a non-contact manner on the surface of the measurement object 1, the ultrasonic wave 5 propagates through the measurement object 1 and the liquid phase 7 (or acoustic characteristic change region 21) on the propagation path. Is reflected (or scattered, diffracted, transmitted). Here, for simplicity, it is assumed that the liquid phase 7 exists on the propagation path. The reflected ultrasonic waves 9 and 10 are detected by the ultrasonic receiving means 12 in a non-contact manner.

  Here, in the propagation time measuring unit 13, the ultrasonic wave is calculated from the difference between the transmission time t 0 when the ultrasonic wave transmission unit 11 transmits the ultrasonic wave 5 and the reception time tr when the ultrasonic wave reception unit 12 receives the reflected waves 9 and 10. Is measured. On the other hand, the temperature of the front surface and the back surface of the measuring object 1 is measured by the temperature measuring means 14.

  That is, the propagation time measuring unit 13 converts a reflected, scattered, diffracted, or transmitted basic ultrasonic waveform prepared in advance into an arbitrary signal waveform that can specify the generation time for each reflected wave; and Arbitrary signal waveform in which the reception time of the ultrasonic reception means can be specified by the number of the reflected, scattered, diffracted or transmitted ultrasonic waves included in the reception signal from the ultrasonic reception means 12 by the signal conversion function. In addition, a reception time measurement function that measures the reception time of each reflected wave from the converted signal converted by the signal conversion function, and a time difference detection that detects a time difference between the transmission time t0 and the reception times tr9 and tr10 (tr22, tr23). With functionality.

  As shown in FIG. 10 (a), the thickness of the solid phase 8 is ds, the thickness of the liquid phase 7 is dL, the temperature of the ultrasonic excitation detection surface is Ts, the temperature of the back surface is Tr, and the solid phase. The temperature of the interface between 8 and the liquid phase 7 is Tb. Here, the temperature Ts and the temperature Tr are quantities measured by the temperature measuring unit 14, and the temperature Tb is a melting point of the measurement target 1, and thus is known as a physical property value of the measurement target. Accordingly, if the temperatures at these three locations and the thermal conductivities in the solid phase 8 and the liquid phase 7 of the measurement object 1 are known, the ultrasonic wave 5 is obtained with the quantities ds and dL to be measured as unknowns as shown in FIG. A temperature distribution along the propagation path can be assumed.

  Here, if the thickness d of the measurement object 1 is measured in advance and the expansion due to the generation of the liquid phase 7 is sufficiently smaller than d, the thickness d is expressed by the following equation (3). Therefore, if the thickness d of the measurement object 1 is prepared in the database 27 in advance, the unknown can be reduced to either one of ds or dL.

d = ds + dL (3)
Next, the propagation time measuring means 13 is defined as a time required for the ultrasonic wave to propagate the temperature field of the temperature distribution T (x) including either the unknown ds or dL by the thickness d (2d in the case of reciprocation). Since Δt is obtained at, the unknown quantity ds or dL is obtained by the temperature distribution estimating means 28 from these quantities.

  Thus, in the fifth embodiment, the temperature distribution state inside the medium is estimated from the propagation information of the ultrasonic wave and the temperature or temperature distribution information of the medium, and the boundary position of the phase change in the thickness or depth direction of the medium. Alternatively, the composition state in the depth direction is measured.

  Next, a sixth embodiment of the present invention will be described. FIG. 11 is a configuration diagram of an ultrasonic measurement apparatus according to the sixth embodiment of the present invention. This sixth embodiment differs from the fifth embodiment shown in FIG. 9 in a two-dimensional position that does not include the depth direction in which the ultrasonic wave 5 is excited by the ultrasonic wave transmission means 11 for the measurement target 1. Alternatively, the transmission position scanning unit 17 for arbitrarily driving the traveling direction of the ultrasonic wave 5 and the ultrasonic wave receiving unit for the ultrasonic wave 5 or the reflected waves 9 and 10 (or the ultrasonic waves 21 and 22) propagated through the measurement object 1. The position information out2 is inputted from the reception position scanning means 18, the transmission position scanning means 17 and the reception position scanning means 18 for arbitrarily driving the two-dimensional detection position not including the depth direction by the reference numeral 12. The recording means 19 for recording the output signal out4 of the temperature distribution estimating means 28 in association with the positional information out2 and the information recorded in the recording means 19 is displayed as a numerical table, a graph or an image. Those provided by adding a display unit 20. Thereby, the distribution shape of the liquid phase 7 (or the acoustic characteristic changing region 21) is measured.

  Further, a measurement target position scanning unit that scans the measurement target 1 two-dimensionally without including the depth direction while the transmission position and the reception position of the ultrasonic waves in the transmission position scanning unit 17 and the reception position scanning unit 18 are fixed. The distribution shape of the liquid phase 7 (or the acoustic characteristic change region 21) can be similarly measured by providing the liquid phase 7 as well.

  A transmission position scanning unit 17 is provided to arbitrarily determine the transmission position pe of the ultrasonic wave 5 by the ultrasonic transmission unit 11, and a reception position scanning unit 18 is provided to arbitrarily set the reception position pr of the ultrasonic wave 5 by the ultrasonic wave reception / transmission unit 12. Can be determined. Thereby, the temperature distribution of the propagation path at each position is obtained. Accordingly, it is possible to measure a two-dimensional distribution or a three-dimensional shape of the phase change position or the acoustic characteristic change region.

  As described above, in the sixth embodiment, by using the non-contact ultrasonic transmission unit 11 and the ultrasonic reception unit 12, the ultrasonic transmission position or transmission direction relative to the medium of the measurement target 1, the super The sound wave reception position and both are scanned two-dimensionally, and the medium, phase change region, or composition state distribution is reconstructed three-dimensionally.

  Examples of the present invention will be described below. FIG. 12 is a block diagram of the first embodiment of the present invention, and is an embodiment relating to the first embodiment shown in FIG. The ultrasonic transmission unit 11 includes an Nd: YAG laser light source 31, an irradiation optical system 32, and an analog / digital converter 40b. The ultrasonic reception unit 12 includes a He-Ne laser light source 35, a Michelson interferometer 36, The signal averager 37, the signal amplifier 38, the band pass filter 39, and the analog / digital converter 40a are configured. The temperature measuring unit 14a includes the thermocouple 42a and the analog / digital converter 40c, and the temperature measuring unit 4b includes It is composed of a thermocouple 42b and an analog / digital converter 40d. The digital computer 41 has a function of achieving the propagation time measurement means 13, the speed calibration means 15, and the propagation path length measurement means 16.

  In FIG. 12, first, the measurement target 1 is a groove shape having a known dimension at an angle φ, and the inclined surface of the measurement target 1 is a system in which the additive 30 is melted by the torch 29. A point pe on the upper surface of the measurement object 1 is irradiated with short pulse high energy laser light from the Q switch Nd: YAG laser light source 31 through the irradiation optical system 32. If it does in this way, the ultrasonic wave 5 which made the irradiation point pe a sound source will propagate to the inside of the measuring object 1.

  Here, there are various methods for determining the directivity of the ultrasonic wave 5 at a certain angle θ, but this mechanism is included in the irradiation optical system 32, and the propagation directivity of the ultrasonic wave 5 is now in a relationship of φ <θ. Suppose that In addition to the laser light source using Nd: YAG as a medium, a CO2 laser that oscillates in the infrared region, an excimer laser that oscillates in the ultraviolet region, a small semiconductor laser, and the like can also be used.

  Further, the ultrasonic wave 5 incident at the directivity angle θ from the irradiation point pe appropriately selected from the dimension and shape of the measurement object 1 propagates through the measurement object 1 and the base metal 33 and the molten metal 34 on the slope of the measurement object 1. To reach the interface. The ultrasonic wave 5 that has reached the boundary surface is reflected in the direction determined by the law of reflection, and reaches a point pr having a geometrically determined upper surface of the measurement object. This point pr is irradiated with laser light from a He—Ne laser light source 35 via a Michelson interferometer 36. The irradiation laser light reflected at the point pr returns to the Michelson interferometer 36 again. At this time, if the point pr is minutely oscillated by the arrival of the ultrasonic wave, a time difference occurs in the phase of the return light, It appears as a time change in the output signal of the Michelson interferometer 36.

  Here, a semiconductor laser or a semiconductor-excited solid laser can be used as a laser light source for measurement, and a micro-vibration measurement includes a deflection direction detector (knife edge method), a time difference interferometer, a heterodyne interferometer, and a transmission type. Alternatively, a reflective Fabry-Perot interferometer can be used instead. The ultrasonic signal detected by the Michelson interferometer 36 is averaged by a signal averager 37 using the oscillation timing of the Nd: YAG laser light source 31 as a reference time, and a signal amplifier 38, a bandpass filter 39, and an analog / digital signal. The data is input to the digital computer 41 via the converter 40a.

  Similarly, an oscillation timing signal of the Nd: YAG laser light source 31 is also input to the digital computer 41 via the analog / digital converter 40b. In addition, thermocouples 42a and 42b are installed on the front and back surfaces of the measurement object 1, and the temperature of each installation point is measured. These measured values are also input to the digital computer 41 via the analog / digital converters 40c and 40d. A non-contact thermometer such as a radiation thermometer or an infrared camera can be used as the temperature measuring device of the measurement object 1.

  The digital computer 41 has three functions. That is, a propagation time measurement function (propagation time measurement means 13) for obtaining a time difference Δt between the input oscillation timing signal of the Nd: YAG laser light source 31 and the detected ultrasonic signal, and the input temperature measurement value are prepared in advance. A speed calibration function (speed calibration means 15) for estimating the temperature distribution from the data such as the thickness of the measurement object 1 and the thermal conductivity, and calibrating the sound speed from the data indicating the temperature-sound speed relationship prepared in advance; The propagation path length is calculated from the output signals of the propagation time measurement function and the speed calibration function, and compared with the dimension / shape data of the measurement object 1 prepared in advance, the boundary surface between the base metal 33 and the molten metal 34, that is, It is a propagation path length measurement function (propagation path length measurement means 16) which measures the penetration depth of a molten metal. Accordingly, it is possible to measure the penetration depth of the molten metal during welding, which has been difficult to measure due to high temperature and high electrical noise.

  Next, FIG. 13 is a block diagram of the second embodiment of the present invention, and is an embodiment relating to the second embodiment shown in FIG. In the second embodiment of the present invention, a two-dimensional galvanometer mirror 45, a sensor 47a, and an analog / digital converter 40e are added as transmission position scanning means 17 to the first embodiment shown in FIG. As the reception position scanning means 18, a two-dimensional galvanometer mirror 46, a sensor 47b, and an analog / digital converter 40f are additionally provided. Thereby, the penetration depth of the molten metal can be measured as a distribution.

  In FIG. 13, a two-dimensional galvanometer mirror 45 for scanning a point pe irradiated with a short-pulse high-energy laser beam from the Q-switch Nd: YAG laser light source 31 on the upper surface of the measurement object 1 via the irradiation optical system 32. Is installed. Along with this, a two-dimensional galvanometer mirror 46 for scanning a point pr irradiated with laser light from the He-Ne laser light source 35 via the Michelson interferometer 36 is installed.

  These two-dimensional galvanometer mirrors 45 and 46 can be replaced by a two-dimensional polygon mirror, a two-dimensional acoustooptic deflector, etc. Also, with respect to the two-dimensional galvanometer mirror 45, the irradiation point pe is not scanned, but the irradiation point is at the same position. It can also be replaced by scanning the directivity angle θ of the incident ultrasonic wave 5. These two-dimensional galvanometer mirrors 45 and 46 are provided with sensors 47a and 47b for detecting the irradiation point or angle, and these measurement results are sent to the digital computer 41 via the analog / digital converters 40e and 40f. Entered.

  The digital computer 41 has the three functions shown in the first embodiment, that is, a propagation time measurement function (propagation time measurement means 13), a speed calibration function (speed calibration means 15), and a propagation path length measurement function (propagation path length measurement means). 16), a memory function (recording means 19) for storing the measurement data measured by the propagation path length measurement function (propagation path length measurement means 16) in correspondence with the measurement data of the sensors 47a and 47b, and the results It has a display function (display means 20) for displaying on the display device 49 as a table, graph or image. Therefore, it is possible to three-dimensionally reconstruct the penetration depth of the molten metal during welding.

  Next, FIG. 14 is a block diagram of the third embodiment of the present invention, and is an embodiment relating to the second embodiment shown in FIG. This third embodiment of the present invention is different from the second embodiment shown in FIG. 13 in that an optical fiber 50, a drive mechanism 52, and a sensor 47c are provided in place of the two-dimensional galvanometer mirror 45 and the sensor 47a. Instead of the three-dimensional galvanometer mirror 46 and the sensor 47b, an optical fiber 51, a drive mechanism 53, and a sensor 47d are provided.

  In FIG. 14, short pulse high energy laser light oscillated from a Q-switched Nd: YAG laser light source 31 is incident on an irradiation optical system 32 via an optical fiber 50. Laser light emitted from the He—Ne laser light source 35 via the Michelson interferometer 36 is irradiated to the irradiation point pr via the optical fiber 51.

  The irradiation point pe and the irradiation point pr are scanned by driving mechanisms 52 and 53 including motors, rails, gears, and the like that mechanically drive and scan the optical fibers 50 and 51. Sensors 47c and 47d for knowing the irradiation points are attached to the drive mechanisms 52 and 53, respectively, and the penetration depth of the molten metal being welded is reconstructed three-dimensionally from these output signals. This is possible because of the same action as in the second embodiment. In this way, it is possible to measure even at a site where it is difficult to handle laser light, such as a measurement object in a narrow part.

  Here, in order to prevent disturbance due to reflected light or scattered light generated on the surface of the measurement object 1, an ultrasonic transmission point by the laser light of the ultrasonic transmission means 11 and an ultrasonic wave by the laser light of the ultrasonic reception means 12. A shielding plate may be provided between the reception points.

  When ultrasonic waves are transmitted using laser light, it is necessary to irradiate the measurement target 1 with relatively high energy laser light, and thus the reflected light or scattered light, or when the measurement target surface is vaporized, is emitted. Light emission, dense waves, dust, etc. may cause disturbance to the laser device (ultrasonic wave receiving means 12) on the ultrasonic wave receiving side. Therefore, by providing a shielding plate between the ultrasonic transmission point and the reception point, the influence can be avoided.

The lineblock diagram of the ultrasonic measuring device concerning a 1st embodiment of the present invention. Explanatory drawing of the signal waveform measured by the ultrasonic wave receiving means in the 1st Embodiment of this invention. The characteristic view which shows the relationship between the temperature calibrated with the speed calibration means in the 1st Embodiment of this invention, and propagation velocity (sound speed). Explanatory drawing in the case of correcting measurement data in consideration of the distance between the ultrasonic transmission position by the ultrasonic transmission means and the ultrasonic reception position by the ultrasonic reception means in the first embodiment of the present invention. . Explanatory drawing of the ultrasonic measuring device in case the measurement object in the 1st Embodiment of this invention does not have phase changes, such as a liquid phase and a solid phase. Explanatory drawing of the ultrasonic measuring device concerning the 2nd Embodiment of this invention. Explanatory drawing of the ultrasonic measuring device concerning the 3rd Embodiment of this invention. Explanatory drawing of the ultrasonic measuring device concerning the 4th Embodiment of this invention. Explanatory drawing of the ultrasonic measuring device concerning the 5th Embodiment of this invention. Explanatory drawing of the estimation method of temperature distribution in the 5th Embodiment of this invention. Explanatory drawing of the ultrasonic measuring device concerning the 6th Embodiment of this invention. The block diagram of the 1st Example of this invention. The block diagram of the 2nd Example of this invention. The block diagram of the 3rd Example of this invention. Explanatory drawing of the conventional ultrasonic measuring device in case a measurement object is a solid phase. Explanatory drawing of the conventional ultrasonic measuring device in case a measurement object contains a solid phase and a liquid phase.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measurement object 2 Kaplan 3 Ultrasonic probe 4 Transmitter 5 Ultrasonic wave 6 Signal detector 7 Liquid phase 8 Solid phase 9, 10 Reflected wave 11 Ultrasonic transmission means 12 Ultrasonic reception means 13 Propagation time measurement means 14 Temperature measurement Means 15 Speed calibration means 16 Propagation path length measurement means 17 Transmission position scanning means 18 Reception position scanning means 19 Recording means 20 Display means 21 Acoustic characteristic change regions 22, 23 Ultrasound 24 Database 25 Signal waveform evaluation means 26 Propagation path diagnosis means 27 Database 28 Temperature distribution estimation means 29 Torch 30 Additive material 31 Nd: YAG laser light source 32 Irradiation optical system 33 Base metal 34 Molten metal 35 He-Ne laser light source 36 Michelson interferometer 37 Signal averager 38 Signal amplifier 39 Band pass Filter 40 Analog to digital converter 41 Digital computer 42 Thermocouple 45, 4 2D galvanometer mirror 47 sensor 49 display device 50 and 51 optical fibers 52, 53 drive mechanism

Claims (13)

  Ultrasonic transmission means for exciting ultrasonic waves in a part of the measurement object without contact, ultrasonic reception means for detecting the ultrasonic waves propagated through the measurement object in non-contact, and the ultrasonic transmission means for the ultrasonic transmission A propagation time measuring means for measuring a propagation time of the ultrasonic wave from a time difference between a transmission time at which the sound wave is transmitted and a reception time at which the ultrasonic wave receiving means receives the ultrasonic wave; and a temperature or a temperature distribution of the measurement object is measured. A temperature measurement unit; a temperature distribution estimation unit that estimates a temperature distribution inside the measurement object along a propagation direction of ultrasonic waves from a surface temperature or a surface temperature distribution measured by the temperature measurement unit; and the temperature distribution estimation unit Speed calibration means for calibrating the propagation speed of the ultrasonic wave propagating in the measurement object from the temperature distribution estimated in (1), the propagation time measured by the propagation time measurement means, and the propagation obtained by the speed calibration means. Degrees from the ultrasonic measuring apparatus characterized by comprising a propagation path length measuring means for calculating a propagation path length of the ultrasonic wave.   Non-contact ultrasonic transmission means for exciting ultrasonic waves to a part of the measurement target, and non-contact reflected waves generated by reflection of the ultrasonic wave propagating through the measurement target in the acoustic characteristic change region on the propagation path And measuring the ultrasonic wave propagation time from the time difference between the transmission time at which the ultrasonic wave was transmitted by the ultrasonic wave transmission unit and the reception time at which the ultrasonic wave reception unit received the reflected wave. A propagation time measuring means, a temperature measuring means for measuring the temperature or temperature distribution of the measurement object, a surface temperature measured by the temperature measurement means or a temperature distribution of the surface of the measurement object along the ultrasonic wave propagation direction. A temperature distribution estimating unit that estimates an internal temperature distribution, a speed calibration unit that calibrates a propagation speed of an ultrasonic wave propagating through the measurement object from the temperature distribution estimated by the temperature distribution estimating unit, and the propagation time meter Ultrasonic measuring apparatus characterized by comprising a propagation path length measuring means for calculating a propagation path length of the ultrasonic wave from the propagation time and the propagation velocity obtained with at the speed calibration means measured by means.   The ultrasonic measurement apparatus according to claim 1 or 2, wherein a transmission position scan for arbitrarily driving a position at which the ultrasonic wave is excited by the ultrasonic wave transmission means or a traveling direction of the ultrasonic wave with respect to the measurement object. Means, reception position scanning means for arbitrarily driving the detection position of the ultrasonic wave or reflected wave propagated through the measurement object by the ultrasonic wave reception means, the transmission position scanning means, and the reception position scanning means And recording means for recording the output signal of the propagation path length measuring means in each positional relationship in association with the position information, and the information recorded in the recording means as a numerical table or graph or An ultrasonic measurement apparatus comprising: display means for displaying as an image.   3. The ultrasonic measurement apparatus according to claim 1, wherein a measurement target position scanning unit for driving a position of the measurement target with respect to the ultrasonic transmission unit and the ultrasonic reception unit, and the measurement target position scan. The position information is inputted from the means, and the recording means for recording the output signal of the propagation path length measuring means in each positional relationship in association with the position information, and the information recorded in the recording means is a numerical table or graph Alternatively, an ultrasonic measurement apparatus comprising display means for displaying as an image.   Ultrasonic transmission means for exciting ultrasonic waves in a non-contact manner on a part to be measured, and an ultrasonic wave that is reflected, scattered, diffracted or transmitted in an acoustic characteristic changing region on the propagation path. Ultrasonic wave receiving means for detecting sound waves in a non-contact manner, temperature measuring means for measuring the temperature or temperature distribution of the measurement object, and in the propagation direction of ultrasonic waves from the surface temperature or surface temperature distribution measured by the temperature measuring means A temperature distribution estimator for estimating the temperature distribution inside the measurement object along, and a speed calibration means for calibrating the propagation speed of the ultrasonic wave propagating through the measurement object from the temperature distribution estimated by the temperature distribution estimator; A signal waveform evaluation unit that compares a signal received by the ultrasonic wave reception unit with a reference signal prepared in advance in consideration of a propagation velocity obtained by the velocity calibration unit; Stage evaluation results from characterized by comprising a propagation path diagnosing section for diagnosing the state of the ultrasonic wave propagation path ultrasonic measuring system.   6. The ultrasonic measurement apparatus according to claim 5, wherein the physical quantity to be compared between the reference signal and the received signal in the signal waveform evaluation means is a signal level, frequency spectrum, phase, pulse width, propagation time, or attenuation rate. Or an ultrasonic measurement apparatus characterized by being a combination of a plurality of these physical quantities.   The ultrasonic measurement apparatus according to claim 5 or 6, wherein a transmission position scan for arbitrarily driving a position where ultrasonic waves are excited by the ultrasonic transmission unit or a traveling direction of the ultrasonic waves with respect to the measurement object. A receiving position scanning means for arbitrarily driving the detection position of the ultrasonic wave propagating through the measurement object by the ultrasonic receiving means, the transmission position scanning means, and the receiving position scanning means. Recording means for inputting positional information and recording the output information of the propagation path diagnosis means in each positional relationship in association with the positional information, and displaying the information recorded in the recording means as a numerical table, a graph or an image An ultrasonic measurement apparatus comprising: a display unit.   The ultrasonic measurement apparatus according to claim 5 or 6, wherein a measurement target position scanning unit for driving a position of the measurement target with respect to the ultrasonic transmission unit and the ultrasonic reception unit, and the measurement target position scan Recording means for inputting the position information from the means and recording the output information of the propagation path diagnosis means in each positional relationship in association with the position information, and the information recorded in the recording means as a numerical table, graph or image An ultrasonic measurement apparatus comprising: a display unit configured to display as:   5. The ultrasonic measurement apparatus according to claim 1, wherein the ultrasonic transmission means is a laser light that is intermittently or modulated in terms of time and generates thermal distortion or ablation on the measurement target surface. It is characterized in that a laser beam focused spatially in the form of dots, circles, ellipses, lines, concentric circles, dots, or lattices is used up to an energy density necessary and sufficient Ultrasonic measuring device.   10. The ultrasonic measurement apparatus according to claim 9, wherein the laser light used as the ultrasonic transmission means is guided from the light source to the vicinity of the irradiation position on the measurement target by an optical fiber.   5. The ultrasonic measurement apparatus according to claim 1, wherein the ultrasonic wave detection means uses an interference phenomenon or a deflection phenomenon of laser light for detection of ultrasonic waves. .   12. The ultrasonic measurement apparatus according to claim 11, wherein the laser beam used as the ultrasonic wave receiving means is guided from the light source to the vicinity of the detection irradiation position on the measurement object by an optical fiber, and the reflected light is the same or different. An ultrasonic measurement apparatus characterized in that an interference mechanism or a deflection detection mechanism is guided by an optical fiber.   13. The ultrasonic measurement apparatus according to claim 9, wherein a shielding plate is disposed between an ultrasonic transmission point by the laser beam of the ultrasonic transmission unit and an ultrasonic reception point by the laser beam of the ultrasonic reception unit. An ultrasonic measurement apparatus characterized by comprising:

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