JP2003329652A - Ultrasonic flaw detector and ultrasonic flaw detecting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, in the case of inspecting a wide range, it is necessary to scan transmitting and receiving probes at the same time, and it takes much time for the probes to scan. <P>SOLUTION: This ultrasonic flaw detector includes a probe 1 transmitting an ultrasonic wave to the air according to a driving signal and propagating the ultrasonic wave through a body to be tested 5, a laser oscillator 2 for radiating a laser beam to the surface which is the opposite side to the back of the body to be tested where the ultrasonic wave enters, a scanning mechanism part 9 for scanning the probe extending over a designated range of the body to be tested, a scanning mechanism part for electrically scanning the laser beam extending over a designated range of the body to be tested, and a laser displacement gauge 4 for measuring the vibration of the surface of the body to be tested. Thus, scanning is simplified, and in the case of inspecting a large body to be tested, the inspection time can be remarkably reduced. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic flaw detector and an ultrasonic flaw detection method for nondestructively inspecting flaws in a solid. In particular, the present invention relates to an ultrasonic flaw detection apparatus and an ultrasonic flaw detection method for inspecting a probe and a test body in a non-contact manner by propagating ultrasonic waves in the air.

[0002]

2. Description of the Related Art Conventionally, this type of non-contact flaw detection method is described, for example, in "Inspection Technology", June 2000, No. 46.
Pages 50 to 50 (hereinafter, referred to as "Document A").

A conventional ultrasonic flaw detector will be described with reference to the drawings. FIG. 5: is a figure for demonstrating the conventional aerial ultrasonic flaw detection method quoted from the said literature A.

In FIG. 5, 1 is a transmitting probe, 5 is a test body, and 11 is a receiving probe.

Next, the operation of the conventional ultrasonic flaw detector will be described with reference to the drawings.

Although not shown in FIG. 5, a drive device for driving the probe is connected to the transmitting probe 1 via a probe cable. The transmitting probe 1 is driven by the signal, and ultrasonic waves are emitted into the air.

Most of the energy of this ultrasonic wave is reflected on the surface of the test body 5, but part of it is transmitted into the test body 5. This transmitted ultrasonic wave is transmitted through the test body 5 when there is no flaw in the test body 5, propagates to the air again, and then is received by the receiving probe 11.

On the other hand, when there is a flaw in the test body 5 and this flaw is on the propagation path of the ultrasonic wave, the ultrasonic wave is reflected by the flaw, so that the ultrasonic wave does not reach the receiving probe 11. Not received.

That is, the transmitting probe 1 and the receiving probe 11 are scanned within a predetermined range, and when ultrasonic waves are received, it is determined that there is no flaw, and if ultrasonic waves are not received, that portion is detected. It is judged that there is a scratch on the.

A flaw detection method in which transmission is performed by ultrasonic waves and reception is performed by a laser displacement meter is disclosed in, for example, Japanese Patent Laid-Open No. 61-1697.
It is also described in Japanese Patent Publication No. 59. However, the method described in this publication does not describe a method for flaw detection in a wide range, and does not describe a scanning method.

Further, Japanese Unexamined Patent Publication No. 64-26147 discloses a method in which ultrasonic waves are generated in a test body by using a pulse laser and reception is performed by using a laser. In this publication, too. There is no description about the flaw detection in a wide area, and no description about the scanning method.

[0012]

In the conventional ultrasonic flaw detector as described above, when inspecting a wide range, it is necessary to simultaneously scan the transmitting probe 1 and the receiving probe 11. However, there is a problem that it takes time to scan the probe.

The present invention has been made to solve the above-mentioned problems, and uses an ultrasonic probe for transmission and a laser displacement meter for reception to inspect a test body over a wide range. An object of the present invention is to provide an ultrasonic flaw detector and an ultrasonic flaw detection method that can reduce the time and effort required for scanning the receiving probe by scanning the probe and the laser beam.

[0014]

An ultrasonic flaw detector according to claim 1 of the present invention is a probe for transmitting an ultrasonic wave into the air based on a drive signal and propagating the ultrasonic wave into a test body. And a laser oscillator for irradiating a laser beam to the surface opposite to the back surface of the test body on which the ultrasonic wave is incident, and a probe scanning mechanism for scanning the probe over a predetermined range of the test body. A means, a laser beam scanning mechanism section for electrically scanning the laser beam over a predetermined range of the test body, and a laser displacement meter for measuring the vibration of the surface of the test body.

In the ultrasonic flaw detector according to claim 2 of the present invention, the probe scanning mechanism means includes a scanning mechanism section for mechanically moving the probe in a direction along the back surface of the test body. It was done.

In the ultrasonic flaw detector according to claim 3 of the present invention, the probe scanning mechanism means mechanically swings and scans the probe to propagate ultrasonic waves in the test body. This is a scanning mechanism that changes the direction.

An ultrasonic flaw detector according to a fourth aspect of the present invention electrically connects the probes having an array structure capable of driving the probe scanning mechanism means for each channel over a predetermined range of the test body. This is a control device for scanning.

In the ultrasonic flaw detector according to claim 5 of the present invention, the probe is a focusing probe for focusing ultrasonic waves.

In the ultrasonic flaw detector according to claim 6 of the present invention, the controller controls the timing of driving each channel of the probe to focus and scan the ultrasonic waves. .

In the ultrasonic flaw detector according to claim 7 of the present invention, the laser oscillator outputs a laser beam of visible light.

An ultrasonic flaw detection method according to an eighth aspect of the present invention includes a transmitting step of transmitting an ultrasonic wave into the air based on a drive signal by a probe and propagating the ultrasonic wave into a test body. An irradiation step of irradiating a laser beam onto a surface opposite to the back surface of the test body on which the ultrasonic wave is incident by a laser oscillator; Probe scanning step for scanning over the range, a laser beam scanning step for electrically scanning the laser beam over a predetermined range of the test body by the laser beam scanning mechanism section, and the test body by the laser displacement meter. Measuring step for measuring the vibration of the surface of the.

According to a ninth aspect of the ultrasonic flaw detection method of the present invention, the probe scanning mechanism means comprises a scanning mechanism section for mechanically moving the probe in a direction along the back surface of the test body. It was done.

In the ultrasonic flaw detection method according to a tenth aspect of the present invention, the probe scanning mechanism means mechanically swings and scans the probe to propagate ultrasonic waves in the test body. This is a scanning mechanism that changes the direction.

In the ultrasonic flaw detection method according to an eleventh aspect of the present invention, the probes having an array structure capable of driving the probe scanning mechanism means for each channel are electrically connected over a predetermined range of the test body. This is a control device for scanning.

According to the twelfth aspect of the ultrasonic flaw detection method of the present invention, the probe is a focusing probe for focusing the ultrasonic waves.

In the ultrasonic flaw detection method according to a thirteenth aspect of the present invention, the control device controls the timing of driving each channel of the probe to focus and scan the ultrasonic waves. .

In the ultrasonic flaw detection method according to a fourteenth aspect of the present invention, the laser oscillator outputs a laser beam of visible light.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. An ultrasonic flaw detector according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the configuration of an ultrasonic flaw detector according to Embodiment 1 of the present invention. In each figure, the same reference numerals indicate the same or corresponding parts.

In FIG. 1, 1 is a transmitting probe, 2 is a laser oscillator, 3 is a laser beam, 4 is a laser displacement meter, 5 is a test object, 6 is a test object 5 on the transmitting probe 1 side. The surface (hereinafter referred to as the back surface of the test body 5), 7 is the test body 5
Of the laser oscillator 2 side (hereinafter referred to as the surface of the test body 5), 8 is a scratch in the test body 5, and 9 is the transmitting probe 1.
Is a scanning mechanism unit for scanning. The laser oscillator 2 includes a scanning mechanism unit (not shown) that electrically scans the laser beam 3.

Next, the operation of the ultrasonic flaw detector according to the first embodiment will be described with reference to the drawings.

FIG. 2 is a diagram showing an operating state of the ultrasonic flaw detector according to the first embodiment of the present invention.

Although not shown, a probe driving device is connected to the transmitting probe 1 through a probe cable,
An electric drive signal is applied to the transmitting probe 1 from this probe driving device. In the transmitting probe 1, ultrasonic waves are generated in the air by this drive signal, and the ultrasonic waves propagate toward the back surface 6 of the test body 5.

Most of the energy of the ultrasonic waves propagating in the air and reaching the back surface 6 of the test body 5 is reflected, but part of the energy is transmitted through the test body 5. The transmitted ultrasonic waves propagate through the test body 5. As shown in FIG.
Is on the propagation path of the ultrasonic wave and the size of the scratch 8 is larger than the beam width of the ultrasonic wave propagating in the test body 5, the ultrasonic wave is reflected by the scratch 8.

On the other hand, from the laser oscillator 2, a laser beam 3 is applied to a portion opposite to the portion where the ultrasonic wave generated by the transmitting probe 1 is incident on the test body 5. When the ultrasonic wave is reflected by the scratch 8, the ultrasonic wave has no effect on the surface 7 of the test body 5, so that nothing is measured by the laser displacement meter 4.

Subsequently, as shown in FIG. 2, the scanning mechanism unit 9
Thus, the transmitting probe 1 is scanned in the direction along the back surface 6 of the test body 5. When the transmitting probe 1 reaches a place where there is no scratch 8, the ultrasonic waves propagating in the test body 5 are transmitted to the surface 7 of the test body 5.
Reach up to. Then, the surface 7 of the test body 5 is vibrated.

On the other hand, the electric scanning mechanism provided in the laser oscillator 2 changes the propagation direction of the laser beam 3, and the ultrasonic waves generated by the transmitting probe 1 are transmitted to the test body 5.
The laser beam 3 is applied to the surface on the opposite side of the place where the laser beam 3 is incident. In this case, since the surface 7 of the test body 5 is vibrating, the vibration of the surface 7 of the test body 5 can be measured by the laser displacement meter 4.

When the transmitting probe 1 is scanned by the scanning mechanism section 9 and the laser beam 3 is scanned by the scanning mechanism section provided in the laser oscillator 2, the vibration distribution on the surface 7 of the test body 5 is measured. Since the vibration is not measured at the place where the scratch 8 is present, the scratch 8 can be detected. Further, if the transmitting probe 1 and the laser beam 3 are scanned over a wide range, the location of the scratch 8 can be specified. In this way, the test body 5 can be inspected.

When the test body 5 is inspected with the configuration and operation described above, the following effects are obtained. That is, since the mechanical scanning is performed only by the transmitting probe 1 that generates ultrasonic waves, the scanning becomes simpler than that of the conventional device having a configuration in which the transmitting and receiving are performed by the probe, and a large test object is obtained. When inspecting, the inspection time can be shortened significantly.

If a focusing type probe is used as the transmitting probe 1 and a large ultrasonic wave is generated in the test body 5,
This has the effect of improving the SN ratio.

Further, when the laser beam 3 is made visible, it is possible to see where on the surface 7 of the test body 5 is being inspected, so that the setting of the device can be performed quickly. As a result, there is an effect that the inspection time can be further shortened.

Embodiment 2. An ultrasonic flaw detector according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 3 is a diagram showing the configuration of the ultrasonic flaw detector according to Embodiment 2 of the present invention.

In FIG. 3, the basic structure is the same as that of the first embodiment, but the operation of the scanning mechanism section 9 of the transmitting probe 1 is different.

Next, the operation of the ultrasonic flaw detector according to the second embodiment will be described with reference to the drawings.

Unlike the first embodiment, the scanning mechanism section 9
Is used to scan the transmitting probe 1 by swinging.

By this scanning, the ultrasonic waves emitted from the transmitting probe 1 are obliquely incident on the back surface 6 of the test body 5, but if the incident angle is less than the critical angle, part of the ultrasonic waves will It is refracted and transmitted through the test body 5, and propagates in the test body 5.

If there are no scratches 8 on the propagation path, the ultrasonic waves reach the surface 7 of the test body 5 and vibrate the surface 7 of the test body 5. If this vibration is measured by the laser displacement meter 4 as in the first embodiment, the presence or absence of the scratch 8 and the position of the scratch 8 can be obtained.

When the ultrasonic wave is obliquely incident on the back surface 6 of the test body 5, longitudinal waves and transverse waves propagate in the test body 5, and either wave may be used for the inspection. Absent.

In this way, if the scanning of the transmitting probe 1 is a swing scan, the size of the scanning mechanism 9 can be made small as shown in FIG. 3, and in addition to the effect shown in the first embodiment. There is an effect that inspection can be performed even in a narrow place.

Further, as in the first embodiment, if the focusing probe is used as the transmitting probe 1 and a large ultrasonic wave is generated in the test body 5, the SN ratio is improved. There is.

Further, when the laser beam 3 is made visible, it is possible to see where on the surface 7 of the test body 5 is being inspected, so that the setting of the device can be performed quickly. As a result, there is an effect that the inspection time can be further shortened.

Embodiment 3. An ultrasonic flaw detector according to Embodiment 3 of the present invention will be described with reference to the drawings. FIG. 4 is a diagram showing the configuration of an ultrasonic flaw detector according to Embodiment 3 of the present invention.

In FIG. 4, the structure is almost the same as in the first and second embodiments, but the structures and operations of the transmitting probe 1 and the scanning mechanism section 9 are different. The transmission probe 1 is an array, and can be driven for each channel. Further, a control device 10 for individually driving each channel is connected to the transmitting probe 1.

Next, the operation of the ultrasonic flaw detector according to the third embodiment will be described with reference to the drawings.

From the control device 10, a signal for individually driving each channel of the transmitting probe 1 is applied. By controlling the timing of driving each channel by the control device 10, the propagation direction of the ultrasonic wave emitted from the transmitting probe 1 is changed. That is, the transmitting probe 1 is electrically scanned like a phased array.

The ultrasonic wave emitted from the transmitting probe 1 is obliquely incident on the back surface 6 of the test body 5, but if the incident angle is less than the critical angle, a part of the ultrasonic wave is in the test body 5. The light is refracted and transmitted through and propagates in the test body 5.

If there is no scratch 8 on the propagation path, the ultrasonic wave reaches the surface 7 of the test body 5 and vibrates the surface 7 of the test body 5. If this vibration is measured by the laser displacement meter 4 as in the first embodiment, the presence or absence of the scratch 8 and the position of the scratch 8 can be obtained.

When ultrasonic waves are obliquely incident on the back surface 6 of the test body 5, longitudinal waves and transverse waves propagate in the test body 5. Either wave may be used for the inspection. Absent.

By electrically scanning the transmitting probe 1 in this manner, it is possible to further shorten the inspection time as compared with mechanical scanning. Further, since the scanning mechanism section 9 is not required, in addition to the effects shown in the first embodiment,
The effect is that inspection can be performed even in a narrow space.

By controlling the timing of driving each channel of the transmitting probe 1 by the control device 10, not only changing the propagation direction of the ultrasonic wave but also focusing the ultrasonic wave, the test body 5 Large ultrasonic waves can be generated inside. As a result, there is an effect that the SN ratio is improved.

Further, if the laser beam 3 is made visible, it is possible to see where on the surface 7 of the test body 5 is being inspected, so that the setting of the device can be performed quickly. As a result, there is an effect that the inspection time can be further shortened.

[0061]

As described above, the ultrasonic flaw detector according to claim 1 of the present invention is a probe for transmitting an ultrasonic wave into the air based on a drive signal and propagating the ultrasonic wave into a test body. A probe, a laser oscillator for irradiating a laser beam to a surface opposite to the back surface of the test body on which the ultrasonic wave is incident, and a probe scanning for scanning the probe over a predetermined range of the test body. Since the mechanical means, the laser beam scanning mechanism section for electrically scanning the laser beam over a predetermined range of the test body, and the laser displacement meter for measuring the vibration of the surface of the test body are provided, the scanning is easy. Therefore, in the case of inspecting a large test body, it is possible to significantly reduce the inspection time.

As described above, the ultrasonic flaw detector according to claim 2 of the present invention comprises the probe scanning mechanism means,
Since the scanning mechanism unit that mechanically moves the probe in the direction along the back surface of the test body, the scanning becomes simple,
When inspecting a large test body, it is possible to significantly reduce the inspection time.

In the ultrasonic flaw detector according to claim 3 of the present invention, as described above, the probe scanning mechanism means is
Since the scanning mechanism unit is configured to mechanically swing and scan the probe to change the direction of propagation of ultrasonic waves in the test body, it is possible to perform an inspection even in a narrow place.

In the ultrasonic flaw detector according to claim 4 of the present invention, as described above, the probe scanning mechanism means is
Since the control device electrically scans the probe in the array configuration that can be driven for each channel over a predetermined range of the test body, the inspection time can be further shortened compared to mechanical scanning, and the inspection can be performed even in a narrow place. There is an effect that can be.

As described above, in the ultrasonic flaw detector according to the fifth aspect of the present invention, since the probe is a focusing probe for focusing ultrasonic waves, the SN ratio can be improved. Has the effect.

In the ultrasonic flaw detector according to claim 6 of the present invention, as described above, the controller controls the timing of driving each channel of the probe to focus the ultrasonic waves. Since scanning is performed, there is an effect that the SN ratio can be improved.

As described above, in the ultrasonic flaw detector according to claim 7 of the present invention, since the laser oscillator outputs a laser beam of visible light, the device can be set quickly and the inspection time can be shortened. The effect of being able to further shorten is obtained.

As described above, in the ultrasonic flaw detection method according to the eighth aspect of the present invention, the ultrasonic wave is transmitted to the air based on the drive signal by the probe and the ultrasonic wave is propagated into the test body. By the transmitting step and the laser oscillator,
An irradiation step of irradiating a laser beam to the surface opposite to the back surface of the test body on which the ultrasonic waves are incident,
A probe scanning step of scanning the probe over a predetermined range of the test body by a probe scanning mechanism means;
The laser beam scanning mechanism section includes a laser beam scanning step of electrically scanning the laser beam over a predetermined range of the test body, and a measuring step of measuring the vibration of the surface of the test body with a laser displacement meter. Therefore, the scanning is simplified, and when inspecting a large test body, the inspection time can be greatly shortened.

In the ultrasonic flaw detection method according to the ninth aspect of the present invention, as described above, the probe scanning mechanism means is
Since the scanning mechanism unit that mechanically moves the probe in the direction along the back surface of the test body, the scanning becomes simple,
When inspecting a large test body, it is possible to significantly reduce the inspection time.

In the ultrasonic flaw detection method according to the tenth aspect of the present invention, as described above, the probe scanning mechanism means mechanically swings and scans the probe to cause ultra-ultrasonic inspection in the test body. Since the scanning mechanism unit changes the propagation direction of the sound wave, it is possible to perform an inspection even in a narrow place.

In the ultrasonic flaw detection method according to the eleventh aspect of the present invention, as described above, the probe having the array structure capable of driving the probe scanning mechanism means for each channel is provided in a predetermined position on the test body. Since the control device electrically scans over the range, the inspection time can be further shortened as compared with the mechanical scanning, and the inspection can be performed even in a narrow place.

As described above, in the ultrasonic flaw detection method according to the twelfth aspect of the present invention, since the probe is a focusing type probe for focusing ultrasonic waves, the SN ratio can be improved. Has the effect.

In the ultrasonic flaw detection method according to the thirteenth aspect of the present invention, as described above, the control device controls the timing of driving each channel of the probe to focus the ultrasonic waves. Since scanning is performed, there is an effect that the SN ratio can be improved.

As described above, in the ultrasonic flaw detection method according to the fourteenth aspect of the present invention, since the laser oscillator outputs a laser beam of visible light, the setting of the apparatus can be performed quickly and the inspection time can be shortened. The effect of being able to further shorten is obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an ultrasonic flaw detector according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing an operating state of the ultrasonic flaw detector according to Embodiment 1 of the present invention.

FIG. 3 is a diagram showing a configuration of an ultrasonic flaw detector according to Embodiment 2 of the present invention.

FIG. 4 is a diagram showing a configuration of an ultrasonic flaw detector according to Embodiment 3 of the present invention.

FIG. 5 is a diagram showing a configuration of a conventional ultrasonic flaw detector.

[Explanation of symbols]

1 transmitting probe, 2 laser oscillator, 3 laser beam, 4 laser displacement meter, 5 test body, 6 back surface,
7 surface, 8 scratches, 9 scanning mechanism section, 10 control device.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shuzo Waka             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F term (reference) 2G047 BA04 BC07 BC18 DB03 EA04                       EA09 GA18 GB02 GB24 GD00                       GF18 GF25

Claims (14)

[Claims] 1. A probe for transmitting an ultrasonic wave into the air based on a drive signal and propagating the ultrasonic wave in a test body, and an opposite side of a back surface of the test body on which the ultrasonic wave is incident. A laser oscillator that irradiates a surface with a laser beam, a probe scanning mechanism unit that scans the probe over a predetermined range of the test object, and a laser beam electrically over the predetermined range of the test object. An ultrasonic flaw detector, comprising: a laser beam scanning mechanism for scanning; and a laser displacement meter for measuring the vibration of the surface of the test body. 2. The probe scanning mechanism means is a scanning mechanism section for mechanically moving the probe in a direction along the back surface of the test body. Sonic flaw detector. 3. The probe scanning mechanism means is a scanning mechanism section that mechanically swings and scans the probe to change the propagation direction of ultrasonic waves in the test body. The ultrasonic flaw detector according to claim 1. 4. The probe scanning mechanism means is a control device that electrically scans the arrayed probes that can be driven for each channel over a predetermined range of the test body. Item 1. The ultrasonic flaw detector according to Item 1. 5. The ultrasonic flaw detector according to claim 1, wherein the probe is a focusing probe that focuses ultrasonic waves. 6. The ultrasonic flaw detector according to claim 4, wherein the control unit controls the timing of driving each channel of the probe to focus and scan the ultrasonic waves. 7. The ultrasonic flaw detector according to any one of claims 1 to 6, wherein the laser oscillator outputs a laser beam of visible light. 8. A transmitting step of transmitting an ultrasonic wave into the air on the basis of a drive signal by a probe and propagating the ultrasonic wave in a test body, and a test in which the ultrasonic wave is incident by a laser oscillator. An irradiation step of irradiating a surface opposite to the back surface of the body with a laser beam, and a probe scanning step of scanning the probe over a predetermined range of the test body by a probe scanning mechanism means, The laser beam scanning mechanism section includes a laser beam scanning step of electrically scanning the laser beam over a predetermined range of the test body, and a measuring step of measuring the vibration of the surface of the test body with a laser displacement meter. An ultrasonic flaw detection method characterized by the above. 9. The probe scanning mechanism means is a scanning mechanism unit for mechanically moving the probe in a direction along a back surface of the test body. Sonic flaw detection method. 10. The probe scanning mechanism means is a scanning mechanism unit that mechanically swings and scans the probe to change the propagation direction of ultrasonic waves in the test body. The ultrasonic flaw detection method according to claim 8. 11. The probe scanning mechanism means is a control device that electrically scans the probes of an array configuration that can be driven for each channel over a predetermined range of the test body. Item 9. The ultrasonic flaw detection method according to Item 8. 12. The probe according to claim 8, wherein the probe is a focusing probe for focusing ultrasonic waves.
The ultrasonic flaw detection method described in 0. 13. The control device controls timing of driving each channel of the probe,
The ultrasonic wave is focused and scanned for scanning.
1. The ultrasonic flaw detection method described in 1. 14. The ultrasonic flaw detection method according to claim 8, wherein the laser oscillator outputs a laser beam of visible light.