JP7157430B2 - flaw detector - Google Patents

Description

The present invention relates to a flaw detector.

A discharge tube instantly heats the surface of the object to be inspected, and the movement of heat generated by the heating is visualized and observed with an infrared camera or the like to detect defects such as scratches and density unevenness inside the object. In recent years, non-destructive inspection by infrared thermography, which detects defects and measures defects, has been used.
In general, thermography refers to an image that analyzes infrared radiation emitted from an object and graphically represents the heat distribution.
The flaw detection method using infrared thermography does not require an ultrasonic medium liquid such as water or oil, unlike the ultrasonic flaw detection method. In the manufacturing process of , the use is spreading when you want to perform quick and easy flaw detection online. For example, a flaw detection method using infrared thermography is attracting attention as an effective means for detecting defects in CFRP (carbon fiber reinforced plastic) as well as metal materials.

Specifically, non-destructive inspection using infrared thermography applies heat to the surface of the object to be inspected using a xenon lamp, etc., and the heat diffuses into the interior, detecting changes over time in the temperature of the surface, which changes according to the internal conditions. Then, the situation inside the object to be inspected is analyzed.
If there is a defect inside the inspection object, the speed of the heat that propagates into the inspection object changes, resulting in a local temperature change on the inspection object surface. By detecting this temperature change, it is possible to detect defects occurring inside the inspection object.
Patent Literature 1 discloses an example of a flaw detection method and apparatus using infrared thermography.

The apparatus disclosed in Patent Document 1 measures the temperature of the heated test object 01 using a heating means 02 and a temperature measuring means 03 such as an infrared camera, and obtains data indicating the relationship between time and temperature. (Paragraph 0014 and FIG. 1). Then, by appropriately analyzing the acquired data using the computer in which the data analysis software 05 is installed and the display means 06 for displaying the result image, defect detection is reliably performed (paragraphs 0015 to 0029).

In the above non-destructive inspection by infrared thermography, lamp energy generated by irradiation with the above-mentioned xenon lamp applies heat energy to the object to be inspected. The thermal energy propagates within the material. In the above non-destructive inspection by infrared thermography, the inside of the inspection object is inspected by measuring the state of the propagation with an infrared camera, so the thermal energy heats the surface of the object as uniformly as possible. is required.
Based on the above requirements, the size, intensity, and type of the light source are selected according to the size and material of the object to be inspected, the time interval required for the inspection, and the like, in the non-destructive inspection using the infrared thermography.
In the non-destructive inspection by infrared thermography, one or more of the above-mentioned xenon lamps (xenon flash lamps) are used as a heating device, i.e. a discharge tube which is usually a light source for heating.

The discharge tube, which serves as a light source, generates heat by instantaneously emitting light, and can instantaneously heat an object to be inspected.
Specifically, for the discharge tube such as the xenon lamp, the heating energy required for non-destructive inspection by infrared thermography is secured by light emission in a short time. Furthermore, when the inspection is continuously performed for a long time, the generated heat consumes an extremely large amount of the lamp, and it is necessary to cool the lamp in order to maintain its performance and protect it.
Including the case where the discharge tube is used other than the heating device for non-destructive inspection by infrared thermography, the discharge tube is generally cooled by blowing air to the discharge tube with a fan or by using a heat sink.
However, in the non-destructive inspection by infrared thermography, as described above, a xenon lamp is used to instantaneously and repeatedly emit light accompanied by a large amount of heat generation.
In fields other than non-destructive inspection, it is well known that xenon lamps are used as excitation light sources for YAG lasers. That is, in YAG laser oscillation, a xenon lamp is used as an excitation source. In particular, YAG lasers used for ophthalmologic treatment and skin treatment require rapid repetition of light emission and output stability, so water cooling is generally adopted.
In the YAG laser, unlike the above-described non-destructive inspection in which the light from the light source is diffused and irradiated onto the object, the xenon lamp emits light in a closed space and the light is emitted through the optical fiber without diffusing to the outside. Energy is applied to the laser material which emits a guided laser. In the YAG laser, the lamp and the YAG rod of the laser are collectively submerged in a pool of cooling water for cooling. In the above YAG laser, the trigger voltage required for the lamp to emit light is applied using the housing of the transmitter as an electrode, and the entire inside of the housing is insulated from the outside of the housing.
Regarding the xenon lamp, the fundamental difference between the use for laser oscillation and the use for non-destructive inspection is that the purpose of the laser is to irradiate the laser oscillation material with light energy and concentrate the energy. On the other hand, in the case of non-destructive inspection, the purpose is to irradiate the surface of the object to be inspected with energy as uniformly as possible. This is different from the case of lasers in that they radiate at
As for the irradiation distance, the laser is close distance, but in the case of non-destructive inspection by infrared thermography, it is not always close distance depending on the size of the object to be inspected. Therefore, in the non-destructive inspection by infrared thermography, heat diffusion from the discharge tube is greater than in the case of the laser, and it is necessary to water-cool the discharge tube more effectively.
In view of the above, the inventor of the present invention, as a water cooling method suitable for non-destructive inspection by infrared thermography, performs cooling by passing water using a water cooling tube, like the water cooling unit in the high pressure discharge lamp shown in Patent Document 2. Focused on water cooling.

Japanese Patent No. 5574261 JP 2016-103413 A

A discharge tube such as the above-mentioned xenon lamp emits light by discharging the enclosed gas. In order to generate the discharge, a trigger that induces the discharge, i.e., a discharge that serves as a trigger, is first required, and a trigger wire for triggering the discharge must be arranged in the vicinity of the discharge tube.
Specifically, as shown in FIG. 1 of Patent Document 2, the water cooling unit 20 has a double structure including an inner tube 21 and an outer tube 22 which are cylindrically formed as water cooling tubes. A discharge tube (discharge tube lamp 10 ) is accommodated in the internal space, and cooling water is passed between the inner tube 21 and the outer tube 22 . A clearance (space) for passing the trigger wire is provided between the discharge tube and the inner tube 21 in order to arrange the trigger wire (wire 14) near the discharge tube.
Therefore, in the case of water cooling, a dedicated space for arranging the trigger line, which is the gap, is provided in the vicinity of the discharge tube, particularly outside the diameter (direction) of the discharge tube, so that the discharge from the inner tube 21, that is, the flow path of the cooling water. The tube lamp 10 is separated by an air layer that accommodates the trigger wire, reducing the cooling effect of water flow.
The present invention solves the above problems and makes it possible to effectively water-cool the discharge tube in non-destructive inspection by thermography.

In the present invention, a heating device equipped with a discharge tube that heats the surface of a test material by emitting light, and an image acquisition device that enables observation of changes in heat inside the test material caused by the heating, The observation is for examining defects in the test material, and the heating device includes a trigger conductive section connected to a trigger power supply, and the trigger conductive section applies a trigger voltage that induces discharge of the light from the discharge tube. As for the flaw detector to be supplied, we were able to provide the one that adopts the following configuration.
That is, the heating device includes a cooling section for cooling the discharge tube, and the cooling section water-cools the discharge tube by moving a cooling liquid outside the diameter of the discharge tube. The trigger conductive portion is arranged at a position that does not interfere with the water cooling with respect to the discharge tube.
Investigating defects in the material to be inspected means investigating whether or not the material to be inspected is in the intended state, or how the material to be inspected differs from the intended state. For defects or surface defects, this includes detecting the presence or absence of defects, the size of defects, the location of defects, the shape of defects, or the type of defects. The types of defects include scratches, voids, delamination, uneven density, etc., and include the presence of foreign matter and burrs. The above-mentioned detection includes measuring the position, size, etc. of the detected defect as well as simply detecting the defect by checking the temperature of the object to be inspected.
Further, in the present invention, the cooling section includes a hollow cylindrical section through which the light emitted from the discharge tube is transmitted, the discharge tube is arranged in the hollow portion of the cylindrical section, and the cooling section includes the cylindrical section. A space between the inner peripheral surface of the shaped portion and the outer peripheral surface of the discharge tube is used as a flow path for the cooling liquid, and the cooling liquid flows into the hollow portion, and the cooling liquid is insulated against the trigger voltage. It is possible to provide a flaw detection device having the above-described trigger conductive portion disposed within the above-described flow path.
Further, in the present invention, the cooling unit includes a hollow tubular portion that does not block the dielectric caused by the trigger voltage and transmits the light emitted from the discharge tube, and the discharge tube extends into the hollow portion of the tubular portion. The cooling part has a flow path for flowing the cooling liquid to the hollow part, and the trigger conductive part is arranged radially outside of the cylindrical part.
Furthermore, in the present invention, the heating device includes a reflecting member, and the reflecting member includes a sub-reflecting portion disposed on the opposite side of the test material with the cylindrical portion interposed therebetween, and a main reflecting portion disposed near the test material, and the sub-reflecting portion has a reflecting surface that reflects the light received from the discharge tube toward the test material and the main reflecting portion. wherein the main reflecting portion has a reflecting surface that reflects the light directly received from the discharge tube and the light reflected by the sub-reflecting portion toward the test material, and the main reflecting portion is , a first main reflection portion and a second main reflection portion, the reflection surfaces of the first main reflection portion and the second main reflection portion facing each other, and the first main reflection portion and the second main reflection portion facing each other. Light directed from the discharge tube to the material to be tested passes through between the portions, and the distance between the reflecting surface of the first main reflecting portion and the reflecting surface of the second main reflecting portion is set to the side of the sub-reflecting portion. It was possible to provide a flaw detector that gradually spreads from the side toward the side of the material to be tested.
Further, in the present invention, the sub-reflecting portion is formed separately from the main reflecting portion, and at least the reflecting surfaces of the first main reflecting portion and the second main reflecting portion have the longitudinal direction of the discharge tube. It was possible to provide a flaw detector in which the contour projected onto a plane (virtual plane) orthogonal to the direction exhibits a part of a parabola.
Further, in the present invention, the first main reflection portion extends from one end of the sub-reflection portion and is continuous with the sub-reflection portion, and the second main reflection portion extends from the other end of the sub-reflection portion. A plane that extends and is continuous with the sub-reflection section, and that is perpendicular to the longitudinal direction of the discharge tube with respect to the reflection surface of each of the first main reflection section and the second main reflection section and the reflection surface of the sub-reflection section. It was possible to provide a flaw detection apparatus in which the contour projected onto the (virtual plane) exhibits a continuous parabola.
Furthermore, in the present invention, the image acquisition device acquires an image by infrared thermography with an infrared camera, the trigger conductive part is a trigger wire formed of a metal wire, and the discharge tube is A xenon lamp, wherein the cylindrical portion is a quartz tube, the cooling portion includes a chiller for circulating the cooling liquid, and the heating device holds both ends of the discharge tube together with the cylindrical portion. the heating device includes a base on which the holding portion and the main reflecting portion are attached; the heating device includes a housing; the housing supports the main reflecting portion and the housing The base is detachably attached to the housing, and the housing accommodates at least the discharge tube, the cylindrical section, the trigger conductive section, the holding section, and the sub-reflecting section, and the housing By removing the base from the body, the main reflector remains in the housing, and the discharge tube, the cylindrical section, the trigger conductive section, the holding section, and the sub-reflector are integrated into the housing. We were able to provide a flaw detector that can be taken out from the

In the present invention, a heating device having a discharge tube that heats the surface of a test material and an image acquisition device that enables observation of heat transfer inside the test material are provided. In a flaw detection device for inspecting defects in which a discharge tube is water-cooled, a trigger conductive portion that induces discharge of the discharge tube is made so as not to interfere with the water-cooling, and cooling by water-cooling of the discharge tube is made effective. That is, the present invention eliminates the need to secure a dedicated space for arranging the trigger wire (trigger conductive portion) in the heating device, thereby realizing more effective cooling of the discharge tube by water cooling. The present invention does not provide an air layer that separates the cooling liquid from the discharge tube for the arrangement of the trigger conductive portion, particularly in the radial direction of the discharge tube, which is the direction of light emission.
In addition, the present invention prevents the structure of the heating device from becoming complicated by eliminating the space dedicated to the arrangement from the heating device.
In addition, by arranging the trigger conductive portion in the flow path of the cooling liquid and directly extending the trigger conductive portion along the surface of the discharge tube, the above-described arrangement space exclusively for the trigger conductive portion is not required, and the diameter of the discharge tube is reduced. , it is possible to dispose the trigger conductive portion at the position closest to the discharge tube, making it easier to discharge than when the trigger conductive portion is disposed at another position outside the discharge tube diameter.
Furthermore, in the present invention, the trigger conductive portion can be easily provided to the discharge tube by arranging the trigger conductive portion outside the flow path of the coolant, that is, outside the diameter of the cylindrical portion.
In particular, as in the above inventions of the present application, a) the trigger conductive portion is arranged in the flow path of the cooling liquid, and b) the trigger conductive portion is arranged outside the cylindrical portion positioned outside the flow path of the cooling liquid. As shown in Patent Document 2, an inner tube 21 containing a discharge tube (high-pressure discharge lamp 10) is provided, and a trigger conductive portion (conductive wire 14) is arranged in the space between the inner tube 21 and the discharge tube. As shown in paragraphs 0023, 0024 and FIG. 1, it is not necessary to adopt a configuration in which the inner pipe 21 is arranged between the flow path of the cooling liquid and separated by the above space. Therefore, in each of the above inventions of the present application, unlike Patent Document 2, in which the discharge tube is separated from the cooling liquid flow path to hinder water cooling, water cooling is not hindered by the configuration for arranging the trigger conductive portion. The coolant can be brought into direct contact with the discharge tube, and the discharge tube can be cooled more effectively.
In the case of b) above, there is no need to involve the holding portion in the arrangement of the trigger conductive portion, which facilitates handling of the trigger conductive portion.
Furthermore, the reflecting member that efficiently directs the light emitted by the discharge tube to the test material is composed of a main reflecting portion and a sub-reflecting portion formed separately from the main reflecting portion. It is easy to set the distance between each position of the reflective surface of the reflecting member and the cylindrical portion that is connected to the cooling liquid. Even so, it is easy to make a design that secures an appropriate interval that does not cause discharge to the reflecting member.
Further, by removing the substrate from the housing, the discharge tube, the cylindrical portion, the trigger conductive portion, the holding portion, and the sub-reflecting portion can be taken out from the housing as a unit integrated with the substrate. Maintenance and replacement of main parts are easy.

(A) is an explanatory diagram of an overview of a flaw detection apparatus using infrared thermography according to the present invention, and (B) is an explanatory diagram of an overview of a flaw detection apparatus using infrared thermography according to another embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall explanatory diagram showing one embodiment of a flaw detector according to the present invention; 1A is a schematic longitudinal sectional view showing an embodiment of a heating device provided in a flaw detector according to the present invention, and FIG. 1B is an enlarged sectional view of a main portion of FIG. (A) is a schematic vertical cross-sectional view showing still another embodiment of a heating device provided in the flaw detector according to the present invention, and (B) is an enlarged cross-sectional view of a main part of (A). The top view of the reflecting member shown to FIG. 2, (B) is a front view of the reflecting member of (A). XX sectional view of FIG. 5(B). (A) is a cross-sectional view showing a state in which a discharge tube unit is removed from the main reflector in FIG. 6, and (B) is a plan view of the main reflector in (A). FIG. 5 is a cross-sectional view of a reflecting member of the flaw detector shown in FIG. 4; FIG. 5 is a cross-sectional view showing still another embodiment of the reflecting member of the flaw detector according to the present invention;

(Overview of flaw detector)
The present invention uses a metal material or plastic, a composite material including CFRP (carbon fiber reinforced plastic), a ceramic, or another material as an inspection object, that is, a test material, and heats the test material by irradiating light. Defects in the material to be tested are investigated by observing changes in the heat conducted through the material to be tested caused by the Here, a preferred embodiment of the present invention will be described with reference to drawings, taking CFRP as an example of a material to be tested.
As shown in FIG. 1A, this example analyzes the thermography of the radiant heat from the test material m caused by the light irradiated to the test material m.
As shown in FIGS. 1A and 2, this flaw detector includes an image acquisition device 1 and a heating device 3. As shown in FIG.

(Image acquisition device 1)
The image acquisition device 1 includes an infrared camera 10 and an image processing device 11 .
The infrared camera 10 is directed toward the material to be inspected m and takes a thermographic image of the material to be inspected m. In FIG. 2 , the white arrow indicates the light irradiated toward the material to be inspected m, and the thick solid arrow indicates the infrared rays emitted from the material to be inspected m toward the infrared camera 10 .
When the material to be inspected m is fixed to a predetermined place such as the wall surface of a building, or when the material to be inspected m is heavy and difficult to move, the image acquisition device 1 and the heating device 3 are used for the inspection. The positions of the image acquisition device 1 and the heating device 3 are adjusted so that they are arranged at a place where the material m is present and a necessary distance and direction are taken with respect to the material m to be inspected.
On the other hand, if the material to be inspected m is portable, the position of the material to be inspected m may be adjusted with respect to the image acquisition device 1 and the heating device 3 set at a predetermined location (FIG. 2). The positions of the acquiring device 1, the heating device 3, and the test material m may be adjusted.
If the test material m is lightweight, the position of the test material m is fixed by an appropriate fixing means so that the position of the test material m does not change with respect to the infrared camera 10 and the heating device 3 (discharge tube 4). For example, the material to be tested m may be fixed to the table by holding it with a holder fixed to the table so that the material to be tested m is not damaged (not shown). However, it is not limited to the one in which the test material m is placed at a fixed position and the flaw detection is performed. For example, the present invention also includes testing the test material m on the production line. When performing flaw detection on the test material m on the production line, the discharge tube 4 of the heating device 3 emits light to the test material m moving on the production line, and the test material m is captured by the infrared camera 10. When reaching the front, the line should be stopped and the material to be tested m should be kept still while it is photographed in front of the infrared camera 10 . Further, the infrared camera 10 may be moved in synchronization with the movement of the line, and flaw detection may be performed without stopping the production line. Furthermore, it is also possible to fix the infrared camera 10 and take pictures only when the line passes without stopping the line.

The image processing device 11 visualizes the image captured by the infrared camera 10 and displays it on the monitor so that the operator can analyze it. The display on the monitor may either display the thermal image captured by the infrared camera 10 as it is, or record the thermal image captured by the infrared camera 10 as data, and reproduce and display the recorded data. good.
In this example, the flaw detection apparatus includes an analysis device 2 constructed by a computer (hereinafter referred to as a PC) installed with analysis software. The existence or non-existence of defects and the size of the defects in the inspection are determined, or the PC assists the above determination by the operator.

Further, the image processing device 11 can also be constructed by the PC. Specifically, in this example, the infrared camera 10 is connected to a PC via an image capture board or other well-known interface so that the thermography can be displayed on the monitor 12 of the PC. Further, the image processing device 11 can store captured image data in a storage device provided in the PC, display the stored image data on the monitor 12 , and further display the analysis results on the monitor 12 . For the analysis software, software that also supports importing of the image data may be used.

To briefly touch on the principle of determining the presence or absence of defects, if the test material m has defects F1, F2, F3 such as scratches, peelings, and voids (voids), the heating device 1 gives the test material m The heat generated (a1, a2, a3 in FIG. 1A) is hindered by the air in the defects F1, F2, F3 and the movement of the heat is slowed down. Therefore, the temperature change and temperature change time at the position with defects F1, F2, and F3 (the surface of the test material m irradiated with light) and the temperature at the position without defects (the surface of the test material m irradiated with light) Comparing the change and the temperature change time, the temperature change and the temperature change time are different. By analyzing the temperature change and the temperature change time, it is possible to detect defects in the material to be inspected m and the sizes and positions of the defects. In the PC monitor of FIG. 1A, g1 is the thermal image of the shallowest defect F1, g2 is the thermal image of the defect F2 deeper than the defect F1, and g3 is deeper than the defect F2. 3 shows a thermal image of defect F3 in position.

(Heating device 3)
A first embodiment of the heating device 3 will be described.
As shown in FIG. 2, the heating device 3 includes a discharge tube 4, a holding portion 30, a power source (hereinafter referred to as a power source 5 for light emission), a trigger conductive portion 6, a trigger power source 7, a cooling portion 8, and a reflecting member 9. , and a housing 13 .

The discharge tube 4 is a sealed tube containing a luminous gas that emits light by discharge. Both ends of the discharge tube 4, that is, the positive and negative electrodes 40 of the discharge tube 4 are connected to the electrodes of the power source 5 for light emission of the discharge. The enclosing tube is a transparent quartz tube. In this example, the discharge tube 4 is a xenon lamp filled with xenon gas. A xenon flash lamp is particularly suitable for the discharge tube 4 because it has a short light emission time and can repeat light emission at short time intervals.
The positive and negative electrodes 40 of the discharge tube 4 have an exposed portion 40 a exposed from the discharge tube 4 (quartz tube) and an enclosed portion 40 b enclosed within the discharge tube 4 .

A pair of holding portions 30 are arranged at both ends of the cylindrical discharge tube 4 to hold both ends of the discharge tube 4 . The holding portion 30 is made of a material having insulating properties and heat resistance. Specifically, it is desirable to form the holding portion 30 from a material that insulates the current that flows when the discharge tube 4 discharges and emits light, and has heat resistance that can withstand the high heat instantaneously generated during the discharge and emits light.
The entire retainer 30 can be made of an insulating material such as Teflon, acrylic, or other thermoplastic engineering plastics.
For example, the portion of the holding portion 30 that is affected by heat is preferably made of heat-resistant ceramic. Alternatively, the entire holding portion 30 may be made of heat-resistant ceramic. Alumina ceramic is preferable as the ceramic used for the holding portion 30 . However, it is also possible to use ceramics other than alumina ceramics or materials other than ceramics as long as they have appropriate heat resistance against the heat radiation of the discharge tube 4 .
Materials that can be used for the holding part 30 include, for example, zirconia, silicon carbide, and quartz, in addition to alumina, in the case of heat-resistant fine ceramics.
As shown in FIG. 3A, the interior of the holding portion 30 includes an insertion space 30a into which the end portion of the discharge tube 4 is inserted, and a water communication portion 30b. The end of the discharge tube 4 is fitted into the insertion space 30a.
In this example, a packing 34 made of a silicon-based material, specifically a heat-resistant material such as silicon, is attached to the portion where the discharge tube 4 is inserted into the insertion space 30a. The discharge tube 4 is fitted into the insertion space 30a.
Incidentally, in FIG. 3A, the reflecting member 9 and the housing 13 of the heating device 3 are omitted in order to avoid complication of the drawing.
The exposed portions 40a of the electrodes 40 of the discharge tube 4 pass through the insertion spaces 30a of the holding portions 30, respectively. Wires 51 and 52 connected to the power source 5 for light emission, that is, an input cable for discharge for light emission (input wire ) is connected.
Specifically, sockets 51a and 52a are detachably attached to the exposed portions 40a of the electrodes 40 on the left and right sides of the discharge tube 4 (Fig. 3(A)). One socket 51 a is provided at the end of the one electric wire 51 . The other end of the electric wire 51 is connected to one of the positive and negative poles of the power source 5 for light emission.
The other one socket 52 a is provided at the end of the other one electric wire 52 . The other end of the electric wire 52 is connected to one of the positive and negative poles of the power source 5 for light emission.
By attaching the discharge tube 4 to both sockets 51a and 52a as described above, it becomes electrically connectable to the power source 5 for light emission.
The power source 5 for light emission has a capacitor. The power source 5 for light emission is connected to a commercial power source and stores electricity required for light emission of the discharge tube 4 .

Further, the water communicating portion 30b is a space that communicates with the insertion space 30a at one end and communicates with the outside of the holding portion 30 at the other end.
In this example, the holding portion 30 further includes a lead wire insertion portion 30c having one end communicating with the water communication portion 30b and the other end communicating with the outside of the holding portion 30 .
A pair of holding portions 30 arranged on the left and right sides of the discharge tube 4 shown in FIG. Reference numeral 33 in FIG. 2 denotes a positioning member that fastens the left and right holding parts 30 and determines the position of the holding part 30 with respect to the discharge tube 4 . The pair of positioning members 33 arranged on the outside of the left and right holding portions 30 are plate-like members and have holes h through which the exposed portions 40a of the electrodes 40 pass (FIG. 3). The diameter of the hole h is smaller than the portion of the electrode 40 of the discharge tube 4 other than the exposed portion 40 .
A fastening member 33a is passed through each positioning member 33 at a position other than the hole h (FIG. 2). The fastening member 33a is a bolt having a head that provides a seating surface, and a male thread is formed on the outer peripheral surface of the shaft of the fastening member 33a.
In FIG. 2, only the head portions of the left and right fastening members 33a are shown. The positioning portion 33 is provided with a hole through which the fastening member 33a passes, and the distal end side of the fastening member 33a passing through the hole is screwed into a screw hole provided in the holding portion 30 . A female screw is formed in the screw hole, and the male screw of the fastening member 33a is screwed therein.
The head seat surface of the fastening member 33 a clamps the holding portion 30 and the positioning member 33 by sandwiching the positioning member 33 between itself and the holding portion 30 . A positioning portion 33 fixed to the holding portion 30 positions the discharge tube 4 with respect to the holding portion 30 .
Further, the base 31 is a plate material which is detachably fixed to the housing 13 directly or indirectly by well-known mounting means such as screwing and bolting. The base 31 constitutes a part of the housing 13 by being attached to the housing 13 . For example, in the example shown in FIG. 2, the housing 13 has an opening at the bottom, and the mounting of the base 31 closes the opening.
The discharge tube 4, the cylindrical portion 81, the trigger conductive portion 6, and the holding portion 30 are provided on the upper surface of the base 31, that is, the surface facing the housing 13. By attaching the base 31 to the housing 13, the discharge tube 4 and the cylinder The shaped portion 81 , the trigger conductive portion 6 , the holding portion 30 and the base 31 can be housed together in the housing 13 .
When replacing the discharge tube 4 , the discharge tube 4 , the cylindrical portion 81 , the trigger conductive portion 6 and the holding portion 30 can be removed together with the base 31 by removing the base 31 from the housing 13 . That is, the discharge tube 4, the cylindrical portion 81, the trigger conductive portion 6, the holding portion 30, the jig 32, the positioning member 33, and the base 31 can be integrally attached to and detached from the housing 13 as one unit.
In the example shown in FIG. 2, the trigger power supply 7 is accommodated in the housing 13 separately from the above unit. However, the trigger power supply 7 may be arranged outside the housing 13 .

The trigger conductive portion 6 is, in this example, a lead wire that applies a trigger voltage (hereinafter referred to as trigger wire 6 as necessary).
The proximal end of the trigger line 6 is connected to the output electrode of the trigger power source 7 . A trigger line 6 receives a voltage from a trigger power supply 7 to induce discharge when the discharge tube 4 emits light.
The trigger wire 6 is a bare metal wire that is not covered with an insulating material, and the proximal end of the trigger wire 6 is connected to the trigger power supply 7 via an electric wire 61 covered with an insulating material (hereinafter referred to as a conductive wire 61). It is connected. Specifically, the trigger line 6 (trigger conductive portion 6 ) is connected to the conductive line 61 via the lead line 60 . The trigger wire 6 and the lead wire 60 are integrally formed metal wires. That is, the trigger wire 6 and the lead wire 60 are one wire rod, and here, in the wire rod, the section arranged in the discharge tube 4 and involved in the discharge is called the trigger wire 6, and the section apart from the discharge tube 4 and involved in the discharge is referred to as the trigger wire 6. A section that is not involved is called a leader line 60 .
In the example shown in FIG. 2, the lead wire 60 is passed through the lead wire insertion portion 30c.
A trigger power supply 7 capable of supplying a necessary trigger voltage is employed. Specifically, the trigger power supply 7 employs one capable of supplying a trigger voltage of 20-30 KV.
The trigger power supply 7 is a transformer (trigger transformer), and the primary side of the transformer is connected to the power supply 5 for light emission.
In this example, the trigger wire 6 is a nickel wire. However, as long as the trigger wire 6 is a conductive wire capable of triggering discharge, it is also possible to use a metal wire other than nickel.
The trigger wire 6 may be located at a position that induces a stable discharge toward the discharge tube 4 . The trigger line 6 avoids the exposed portions 40a of the electrodes 40 of the discharge tube 4 and is arranged only between the exposed portions 40a of the positive and negative electrodes of the discharge tube 4 in the longitudinal direction of the discharge tube 4 . In other words, if the trigger wire 6 is arranged only in the section sandwiched between the exposed portions 40a of the positive and negative electrodes 40 in the longitudinal direction of the discharge tube 4, the inner portions 40b of the positive and negative electrodes 40 of the discharge tube 4 and the longitudinal There may be some overlap in terms of orientation position. In the wire rod that provides the trigger wire 6, the lead wire 60 is separated from the outer peripheral surface of the exposed portion 40a to the radially outer side of the exposed portion 40a so as not to discharge.
The light emission power source 5 is connected to the PC via a signal line. The power source 5 for light emission receives a command from the PC when the image acquisition device 1 acquires an image, and discharges the stored charge to the discharge tube 4 . A trigger power supply 7 connected to the light emission power supply 5 supplies a necessary voltage to the trigger line 6 as the light emission power supply 5 discharges the charge.

In this example, the trigger wire 6 is directly wound around the outer peripheral surface of the discharge tube 4 as shown in FIGS. 3(A) and 3(B). That is, the trigger wire 6 is spirally wound around the discharge tube 4 .
The trigger wire 6 is loosely wound around the outer periphery of the discharge tube 4 so as not to hinder the emission of light from the discharge tube 4, and is not tightly wound so as to block the light. The length of the trigger wire 6 can be appropriately changed according to the diameter, length, type, amount of heat generated, and other matters of the discharge tube 4 .
As described above, the trigger wire 6 is not limited to being wound around the discharge tube 4, and may simply run along the outer peripheral surface of the discharge tube 4 without being wound. For example, it may extend straight along the longitudinal direction of the discharge tube 4 . Further, the trigger wire 6 is not limited to contact with the discharge tube 4 , and the trigger wire 6 may be disposed only in the flow path r of the cooling liquid b described later and may not contact the discharge tube 4 .
In addition to the above-described trigger wire 6 in which the entire section contacts the discharge tube 4, or in which the entire section of the trigger line 6 does not contact the discharge tube 4, a part of the trigger line 6 contacts the surface of the discharge tube 4 and the trigger line Other parts of 6 can also be implemented without contact with the discharge tube 4 . For example, the trigger wire 6 wound around the surface of the discharge tube 4 may be partially lifted from the surface of the discharge tube 4 and separated from the discharge tube 4 .
In this example, the tip of the trigger wire 6 is looped 6a and fastened to the outer periphery of the discharge tube 4. As shown in FIG.

In the case of inspecting a wide area of the material to be inspected m by the infrared thermography, a discharge tube 4 having the ability to heat a wide surface by radiating light is employed. Although there is no particular limitation on the power consumption, it is conceivable to adopt a discharge tube 4 that consumes 500 J to 20000 J of power per light emission depending on the test material m and flaw detection conditions. It is conceivable to employ a discharge tube 4 that consumes 1000 J to 12000 J of electric power per light emission.
It has been confirmed that the power consumption of 2000J to 4000J is feasible when detecting peeling on the surface layer of CFRP.
However, it is not excluded that the discharge tube 4 having a capacity outside the above numerical range may be used depending on the material m to be tested. In other words, it does not exclude the use of the discharge tube 4 that consumes less than 500 J or more than 20000 J per light emission.
As the cooling part 8, one having the ability to cool the discharge tube 4 heated by the light emission is used.
The cooling unit 8 will be specifically described.
The cooling unit 8 includes a tubular portion 81 that forms the flow path r for the cooling liquid b, a tank T that supplies the cooling liquid b, and a pump P that circulates the cooling liquid b. Specifically, the tubular portion 81 is a hollow and transparent quartz tube, and the inner diameter of the tubular portion 81 is larger than the outer diameter of the discharge tube 4 . The cylindrical portion 81 is arranged outside the discharge tube 4 . That is, the discharge tube 4 is arranged in the hollow portion of the tubular portion 81 . A gap between the outer peripheral surface of the discharge tube 4 and the inner peripheral surface of the cylindrical portion 81 constitutes the flow path r for the coolant b. The cooling liquid b flows through the gap which is the flow path r, and the cooling liquid b comes into direct contact with the surface of the discharge tube 4 during movement. As described above, the cylindrical portion 81 is a water-cooled tube that forms a flow path for the coolant b outside the diameter of the discharge tube 4 .
The tubular portion 81 is fitted into the insertion space 30 a of the holding portion 30 together with the discharge tube 4 . As shown in FIG. 3A, the cylindrical portion 81 is shorter than the discharge tube 4, and both ends of the discharge tube 4 (exposed portions 40a and 40b of the electrode 40) are cylindrical in the insertion space 30a of the holding portion 30. It protrudes from both ends of the shaped portion 81 . Regarding the diameter of the insertion space 30a, the section into which the tubular portion 81 is inserted is a large-diameter section that is larger than the small-diameter sections that accommodate the exposed portions 40a and 40b. The small-diameter section and the large-diameter section are concentric, and by fitting the tubular portion 81 into the large-diameter section and fitting the discharge tube 4 into the small-diameter section, each circumferential position of the discharge tube 4 and the tubular section 81 can be adjusted. , a gap that becomes the flow path r can be provided evenly.
Also, the packing 34 for preventing water leakage is attached to the exposed portions 40a and 40b of the discharge tube 4 which are fitted in the small-diameter section. A packing 35 made of the same material as the packing 34 for preventing water leakage of the discharge tube 4 is also attached to a portion of the tubular portion 81 that is fitted into the insertion space 30a.
Regarding the cooling liquid b, the packings 34 and 35 prevent it from leaking out of the holding portion 30, so that the heat from the discharge tube 4 can be reliably removed by the cooling liquid b.
In this example, the gap around the lead wire 60 in the lead wire insertion portion 30c is closed with a well-known adhesive or putty having heat resistance to withstand the heat dissipation of the discharge tube 4. As shown in FIG.
The tubular portion 81, that is, the water-cooled tube, emits the light emitted from the discharge tube 4 to the outside and heats the material m to be tested.

A hose 83 for introduction is connected to the water communication portion 30b of the holding portion 30 on one side (left side in FIGS. 2 and 3A), and the hose 83 for introduction is connected to the tank T through the pump P. It is connected. A discharge hose 84 is connected to the water communicating portion 30b of the holding portion 30 on the other side (the right side in FIGS. 2 and 3A), and the collected coolant b is stored in the tank T again.
The cooling liquid b introduced into the water-cooled pipe from the water communication portion 30b of one holding portion 30 flows along the longitudinal direction of the discharge tube 4 and the water-cooled pipe (white arrow in FIG. 3B). It is discharged from the water communicating portion 30b of the portion 30, passes through the tank T, and is introduced again from the water communicating portion 30b of the one holding portion 30 into the water cooling pipe.
Also, the cooling liquid b must be a liquid with insulating properties. Pure water may be used as the cooling liquid b as a liquid having insulating properties.
Although not shown, the tank T or the hoses 83 and 84 are equipped with a temperature sensor and a conductivity meter. The temperature sensor and the conductivity meter are connected to a PC, and if the temperature rises above a predetermined level or the purity of the cooling liquid b changes above a predetermined level, the PC issues an alarm. The operator can confirm by looking at the monitor 12 whether or not the cooling liquid b has a temperature necessary for cooling, and furthermore, whether or not the purity is maintained to provide insulation.
If the insulating property of the cooling liquid b deteriorates, the cooling liquid b in the tank T can be replaced with one having a high insulating property. Even if the temperature of the cooling liquid b rises, it can be dealt with by replacing the cooling liquid b. It is assumed that the temperature of the cooling liquid b is adjusted by operating the cooling device. Therefore, it is sufficient to issue the above alarm only when the purity of the cooling liquid b changes, and it is also possible to connect only the conductivity meter to the PC.
Specifically, the tank T is provided with the cooling device such as a heat exchanger for cooling the contained cooling liquid. The cooling device may be provided in the hoses 83 and 84 separately from the tank T so as to be arranged in the circulation path of the cooling liquid b .
As described above, the cooling liquid b can be maintained at a constant water temperature and maintained as pure water in terms of water quality.
The flow rate and flow velocity of the cooling liquid b are selected according to the characteristics of the lamp and the heating energy. That is, the pump p having the capacity corresponding to the selection of the value is adopted. However, the cooling liquid b may be circulated by a pump provided in the chiller instead of providing the separate pump p.
Further, an ion exchanger may be provided in the middle of the circulation path of the cooling liquid b to automatically restore the insulation of the cooling liquid b when the insulation of the cooling liquid b is lowered.
Although the temperature sensor and the conductivity meter are connected to a PC in the above description, the temperature sensor and the conductivity meter may be connected to a PLC (programmable logic controller) for sequence control.

Examples of the reflecting member 9 are shown in FIGS. 5 to 7. FIG.
The reflecting member 9 efficiently directs the light emitted by the discharge tube 4 toward the test material m.
The reflecting member 9 is a curved plate-like body. The reflecting member 9 is arranged outside the tubular portion 81 with a gap therebetween and surrounds the tubular portion 81 . The inner surface of the curved reflecting member 9 is a reflecting surface 90 that reflects the light from the discharge tube 4 .
Specifically, the reflecting member 9 includes a main reflecting portion 92 and a sub-reflecting portion 91 (FIG. 6).
The secondary reflecting portion 91 is arranged on the opposite side of the test material m with the cylindrical portion 81 interposed therebetween, and the main reflecting portion 92 is arranged closer to the test material m than the secondary reflecting portion 91 is.
The inner surfaces of the main reflecting portion 92 and the sub-reflecting portion 91 form the reflecting surface 90 .
The reflecting surface 90 of the sub-reflecting portion 91 reflects the light received from the discharge tube toward the test material m and the main reflecting portion 92, and the reflecting surface 90 of the main reflecting portion 92 reflects the light received directly from the discharge tube 4 and the sub-reflecting portion. The light reflected by the reflecting portion 91 is reflected toward the test material m.
Further, the main reflection portion 92 includes a first main reflection portion 92a and a second main reflection portion 92b. The reflection surfaces 90 of the first main reflection portion 92a and the second main reflection portion 92b face each other. The first main reflection portion 92a and the second main reflection portion 92b extend from the discharge tube 4 (cylindrical portion 81) side to the test material m side, and are between the first main reflection portion 92a and the second main reflection portion 92b. , the light from the discharge tube 4 to the test material m passes through. In a side view of the reflecting member 9, the distance between the reflecting surfaces 90 of the first main reflecting portion 92a and the second main reflecting portion 92b is gradually widened from the side of the sub-reflecting portion 91 toward the side of the test material m.

As shown in FIGS. 5A and 6, the sub-reflection portion 91 is formed in a gutter shape.
The side surface of the main reflecting portion 92 is covered with a side plate 95 . The inner surface of the side plate 95 has a lower reflectance than the reflecting surface 90 of the main reflecting portion 92 in this example. However, the inner surface of the side plate 95 is not limited to a surface having a lower reflectance than the reflecting surface 90 of the main reflecting portion 92 . It may be the same as the reflectance or greater than the reflectance of the reflecting surface 90 of the main reflecting portion 92 .
In addition, in the main reflection portion 92 consisting of the first main reflection portion 92a and the second main reflection portion 92b, the side plate 95 provides a connection surface for connecting the first main reflection portion 92a and the second main reflection portion 92b ( 5(B) and 6).
For example, the test material m is placed above the discharge tube 4, and light is emitted from below toward the test material m. Assuming that the side plates 95 are arranged in front of the reflecting portion 92b, the side plates 95 are arranged on the left and right sides of the main reflecting portion 92, and are arranged on the left and right sides of the first main reflecting portion 92a and the left and right sides of the second main reflecting portion 92b. connect each of the However, the side plate 95 may not be connected to the first main reflection portion 92a and the second main reflection portion 92b as long as it covers the left and right sides of the main reflection portion 92. As shown in FIG. The side plate 95 does not have to be integrated with the main reflecting portion 92 .
The sub-reflecting portion 91 covers the bottom of the main reflecting portion 92 . In this example, the subreflector 91 is formed separately from the main reflector 92 and can be separated from the main reflector 92 (FIGS. 6 and 7). The upper end of the main reflector 92 is open as a light emission port 93 .
Although not shown, the main reflector 92 is secured to the casing 13 by well-known securing means such as screws, bolts, pins, or welding.

In the example shown in FIGS. 5 to 7, the sub-reflection portion 91 is provided on the base 31 together with the discharge tube 4, the cylindrical portion 81, the trigger conductive portion 6, the holding portion 30, the jig 32, and the positioning member 33. It can be removed from the housing 13 as part of the unit (FIGS. 2, 5-7). By removing the unit from the housing 13 , the sub-reflection section 91 can be separated from the main reflection section 92 fixed to the housing 13 and removed from the housing 13 .
As shown in FIGS. 7A and 7B, the bottom of the main reflector 92 from which the sub-reflector 91 is removed opens as an opening 94 .

As shown in FIG. 6, in this example, the reflecting surfaces 90 of the sub-reflecting portion 91 and the main reflecting portion 92 are projected onto a plane (virtual plane) perpendicular to the longitudinal direction of the discharge tube 4 (cylindrical portion 81). The contour exhibits a parabola.
It is preferable to dispose the discharge tube 4 and the cylindrical portion 81 with respect to the reflecting member 9 so that the focus of the parabola and the central axis (imaginary line) of the discharge tube 4 are aligned. However, even if the central axis of the discharge tube 4 is slightly deviated from the focal point, it is acceptable as long as the reflection is not hindered.
By placing the xenon lamp, which is the discharge tube 4, on the focal point of the paraboloid formed by the reflecting surface of the reflecting member 9, the light emitted by the discharge tube 4 is diffusely reflected, and the heating device 3 emits light from the radiation port 93 to the test object. Emit light towards material m.

At least the reflecting surface 90 of the reflecting member 9 can employ a metal plate having a high reflectance. In this example, aluminum is adopted as the reflecting member 9 . In addition, by distributing a plurality of irregularities on the reflecting surface of the reflecting member 9, the received light can be diffusely reflected to make the light uniform.
In addition to the examples shown in FIGS. 6 and 7, it is assumed that the outline of the main reflection portion 92, that is, the outline of the first main reflection portion 92a and the second main reflection portion 92b exhibits a part of a parabola, and the sub-reflection portion 91 is It may have a contour different from the part of the parabola, and the sub-reflection part 91 may be formed in a shape other than the gutter shape shown in FIGS. Also, the outline of the sub-reflecting portion 91 is not limited to a strict parabola, and may have a shape slightly different from the parabola as long as appropriate reflection can be performed.

Next, a second embodiment of the heating device 3 will be described with reference to FIGS. 4(A) and 4(B).
In this second embodiment, the trigger wire 6 is arranged on the outer peripheral surface of the tubular portion 81 that constitutes the cooling portion 4 .
In this example, the trigger wire 6 is spirally wound around the outer peripheral surface of the tubular portion 81 . However, the trigger wire 6 may simply run along the outer peripheral surface of the tubular portion 81 without being wound.
In the second embodiment shown in FIG. 4, the trigger wire 6 is arranged on the outer peripheral surface of the cylindrical portion 81 that constitutes the cooling portion 4. Can be installed without affecting
Also in the second embodiment, it is preferable that the coolant b has insulating properties. In the second embodiment, the trigger line 6 is not in direct contact with the cooling liquid b, but when a voltage is applied to the trigger line 6, the cooling liquid b is energized and the discharge of light emission is properly induced. This is to avoid a situation in which it cannot be broken.

In the second embodiment, since there is a danger that the trigger wire 6 will discharge to the reflecting member 9 made of aluminum, the distance between the trigger wire 6 and each part of the reflecting member 9 is not caused to cause the discharge. It is necessary to make it a size. It is suitable that the size is 3 mm or more when applying a voltage of 10 to 30 kv to the trigger line 6 . The magnitude may be changed according to the voltage supplied from the trigger line 6 .

Moreover, in the example shown in FIG. 4A, the trigger power supply 7 is attached to the housing 13 with a bracket 14 . The bracket 14 is a plate member formed like a shelf.
The brackets 14 are arranged on the right and left sides of the discharge tube 4 extending left and right and fixed to the housing 13 . An insulator 62 is provided on each of the left and right brackets 14 . The insulators 62 are arranged on the right and left sides above the discharge tube 4 by being provided on each of the shelf portions above the bracket 14 .
The other end of the conductive wire 61 , one end of which is connected to the trigger power supply 7 , is screwed to the insulator 62 of one bracket 14 . The other end of the lead wire 60 extending from one end of the trigger wire 6 wound around the outer peripheral surface of the cylindrical portion 81 is fixed to the insulator 62 together with the conductive wire 61, so that the lead wire 60 and the conductive wire 61 are connected. electrically connected. The side plate 95 is provided with a through portion 96 (FIG. 8). The lead wire 60 passes through the through portion 96 and connects one end of the trigger wire 6 and the conductive wire 61 stopped by the insulator 62 .

As shown in FIG. 4A, the other end of the trigger wire 6 wound around the outer peripheral surface of the cylindrical portion 81 is also connected to the bracket 14 of the trigger power source 7 and the discharge tube 4 (cylindrical portion 81). It is screwed to the insulator 62 of the bracket 14 located on the opposite side. The through portions 96 are formed in the left and right side plates 95 of the main reflection portion 92, respectively. The other lead wire 60 screwed to the insulator 62 of the opposite bracket 14 is also passed through the through portion 96 of the other side plate 95 (FIGS. 4A and 8). In this example, both through portions 96 are cutout portions provided in the side plate 95 , but the through portions 96 may be formed by providing holes in the side plate 95 .
The left and right lead wires 60 are stretched between the trigger wire 6 and the insulator 62 so as to pull both ends of the trigger wire 6 wound around the cylindrical portion 81 . The lead wire 60 is desirably stretched without slack.
In order to ensure insulation between the lead wire 60 and the reflective member 9, the lead wire 60 stretched between the trigger wire 6 and the insulator 62 is in contact with the reflective member 9 (main reflective member 92). shall be large enough not to The penetrating portion 96 is not limited to having the spindle-shaped profile shown in FIG. 8, but may have other shapes. Also, the arrangement of the lead wire 60, the conductive wire 61, the insulator 62, the trigger power source 7, and the bracket 14 is not limited to the one shown in the drawings, and can be changed as appropriate. Furthermore, the shape of the bracket 14 is not limited to the one shown in the drawings, and can be changed as appropriate.

FIG. 9 shows a modified example suitable for securing the distance between the trigger wire 6 and each part of the reflecting member 9 so as not to cause the discharge.
The example shown in FIG. 9 is the same as the examples shown in FIGS. The sub-reflector 91 is spaced apart from the opening 94 of the main reflector 92 instead of aligning the edge of the sub-reflector 94 with the top edge of the sub-reflector 91 . That is, in the state where the base 31 is attached to the housing 13, as shown in FIG. do. Due to this arrangement, the outlines of the sub-reflecting portion 91 and the main reflecting portion 92 each exhibit a part of a parabola, but the parabola as a whole is slightly interrupted. However, it is easy to design to secure a space between the trigger line 6 outside the cylindrical portion 81 and the main reflecting portion 92 .
Matters not particularly mentioned in the second embodiment and the modification shown in FIG. 9 are the same as in the first embodiment.

(Another modification of the device)
In each embodiment shown in FIGS. 3 and 4, the trigger conductive portion 6 is a wire material, that is, the trigger wire 6. However, in each of the embodiments shown in FIGS. 3 and 4, the trigger conductive portion 6 is a plate-like member. (metal plate), or a metal plating layer formed by plating on the surface of the discharge tube 4, the inner peripheral surface of the cylindrical portion 81, or the outer peripheral surface of the cylindrical portion 81.
The cooling unit 8 may have an air-cooling configuration such as a cooling fan in addition to the water-cooling configuration described above.

In addition, the above-described unit is detachable from the housing 13 when replacing the discharge tube 4. Alternatively, the discharge tube 4 may be directly removed from the base 31 together with the cylindrical portion 81. FIG. Specifically, the cylindrical portion 81 containing the discharge tube 4 may be taken out from the emission port 93 of the main reflection portion 92 of the housing 13 shown in FIG. When the tubular portion 81 is taken out from the radiation port 93, the reflecting member 9 and the holding portion 30 are arranged so that the vicinity of both ends of the discharge tube 4 (the exposed portion 40a of the electrode 40) is not obstructed by the side surface portion 95 of the reflecting member 9. It is enough to determine the size and shape.
Further, when the tubular portion 81 is taken out from the radiation port 93 , not only the tubular portion 81 but also the sub-reflecting portion 91 together with the tubular portion 81 may be formed so as to be taken out from the radiation port 93 .
Furthermore, the main reflector 92 may be removed together with the sub-reflector 91 from the housing 13 shown in FIG. When the main reflection portion 92 is removed from the housing 13 together with the sub-reflection portion 91, the main reflection portion 92 is included in the above unit, and the main reflection portion 92 is removed together with the other constituent members of the unit by removing the base 31 from the housing 13. The portion 92 may be removable.
In the example shown in FIG. 2, the base 31 closes the opening at the bottom of the housing 13, but it is also possible to provide an opening for inserting and removing the unit from a portion other than the bottom of the housing 31. FIG. When the unit is taken in and out through an opening other than the bottom of the housing 31, the opening may be closed with a separate cover instead of the base 31 closing the opening.

The sub-reflecting portion 91 may be formed integrally with the main reflecting portion 92 and may be inseparable from the main reflecting portion 92 (not shown). That is, the first main reflection portion 92 a extends from one upper end of the sub-reflection portion 91 and is continuous with the sub-reflection portion 91 , and the second main reflection portion 92 b extends from the other upper end of the sub-reflection portion 91 . It may be extended to be continuous with the sub-reflection portion 91 .
Whether the sub-reflection portion 91 is integrated with the main reflection portion 92 or is separable from the main reflection portion 92, the outline projected onto the plane perpendicular to the longitudinal direction of the discharge tube 4 forms the parabola. is preferred. However, it is not excluded that the contour is another curve that approximates a parabola.
In each of the above descriptions of the reflecting member 9, the material to be tested m is arranged above the discharge tube 4. It is not limited to arranging the material to be tested m.

(Example of change in flaw detection method)
In each of the above-described embodiments, the infrared camera 10 is arranged on the same side as the heating device 3 (discharge tube 4) with respect to the material to be tested m to obtain an image.
In addition, as shown in FIG. 1(B), an infrared camera may be placed on the opposite side of the heating device 3 (discharge tube 4) across the test material m to obtain an image.
In the example shown in FIG. 1B, unlike the example shown in FIG. The heat conducted through the material to be inspected m is observed from the side opposite to the heating device 3 with the material to be inspected m interposed therebetween. In the example shown in FIG. 1B, the test material m is placed on the top c1 of the casing c that covers the infrared camera 10. In the example shown in FIG. The top portion c1 of the casing c on which the test material m is placed has a through portion c2 that penetrates vertically. The material to be tested m is placed on the top of the casing c so as to block the through portion c1. An infrared camera 10 directed toward the through portion c within the casing c can take thermographic images of the heat conducted through the test material m through the through portion c2.
In the example shown in FIG. 1(B) as well, matters not specifically mentioned are the same as in the above-described embodiments.
Moreover, the heating device 3 is not limited to the one used for the above flaw detection device, and may be used for applications other than the above flaw detection device.

(Summary)
A discharge tube 4 such as a xenon lamp used in non-destructive inspection by infrared thermography differs from that for a laser in that a part of the discharge tube 4 is external in order to irradiate the light of the discharge tube 4 toward the test material. must be open to That is, light is projected from the radiation port 93 provided in the reflecting member 9 toward the test material m. Moreover, in the non-destructive inspection, the lamp (discharge tube), the laser rod, and the entire reflecting surface cannot be structurally submerged in water unlike the laser application.
In the non-destructive inspection by infrared thermography, (1) cooling and (2) light irradiation are performed simultaneously. Furthermore, the lamp (discharge tube) is required to (3) emit a high-voltage trigger pulse of 10 to 30 kV from the outside at a required timing in order to discharge.
In the present invention, the cooling unit 8 moves the cooling liquid b on the radially outer side of the discharge tube 4, and the discharge tube 4 is water-cooled. By arranging it in a position where it does not interfere, it is possible to provide a flaw detection apparatus using infrared thermography that satisfies the above requirements (1) to (3).

REFERENCE SIGNS LIST 1 image acquisition device 2 analysis device 3 heating device 4 discharge tube 5 (light emission) power source 6 trigger wire (trigger conductive portion)
6a (of the trigger wire 6) ring 7 trigger power source 8 cooling unit 9 reflecting member 10 infrared camera 11 image processing device 12 monitor 13 housing 14 bracket 30 holding portion 30a insertion space 30b water communication portion 30c lead wire insertion portion 31 base 32 Jig 33 Positioning member 33a Fastening member 34 Packing 35 Packing 40 Electrode (of discharge tube 4) 40a (of electrode 40) Exposed portion 40b (of electrode 40) Inner portion 51 Electric wire 51a (of electric wire 51) socket 52 Electric wire 52a (electric wire 52) ) socket 60 lead wire 61 conductive wire 62 insulator 81 cylindrical portion 83 introduction hose 84 discharge hose 90 reflecting surface 91 sub-reflecting portion 92 main reflecting portion 92a first main reflecting portion 92b second main reflecting portion 93 radiation Port 94 Opening 95 Side plate 96 Penetrating part a1 Heat a2 Heat a3 Heat b Coolant c Casing m Test material r Channel F1 Defect F2 Defect F3 Defect g1 Thermal image of defect F1 g2 Thermal image of defect F2 g3 Heat of defect F3 Image h Hole (of positioning member 33) P Pump T Tank

Claims (6)

A heating device having a discharge tube that heats the surface of a material to be inspected by emitting light, and an image acquisition device that enables observation of changes in heat inside the material to be inspected caused by the heating. A flaw detection apparatus for inspecting defects in the material to be inspected, wherein the heating device includes a trigger conductive section connected to a trigger power source, and the trigger conductive section supplies a trigger voltage for inducing the discharge of the light emitted from the discharge tube. in
The heating device includes a cooling unit that cools the discharge tube, a reflecting member made of aluminum, and a housing,
The cooling part includes a hollow tubular part that does not shield the dielectric due to the trigger voltage and transmits light emitted from the discharge tube, the discharge tube being disposed in the hollow part of the tubular part,
The cooling part water-cools the discharge tube by moving the cooling liquid in a space between the inner peripheral surface of the cylindrical part and the outer peripheral surface of the discharge tube, which is used as a flow path for the cooling liquid. without an air layer separating the liquid from the discharge tube;
The cooling liquid has insulating properties,
The heating device includes a pair of holding portions that hold the both ends of the discharge tube, and the inside of the holding portion has an insertion space into which the end portion of the discharge tube is inserted,
The tubular portion is shorter than the discharge tube, and both ends of the discharge tube extending leftward and rightward protrude from both ends of the tubular portion in the insertion spaces of the respective holding portions,
The holding part is accommodated in the housing together with the cylindrical part,
The reflecting member is a curved plate-like body, is arranged outside the cylindrical portion with a gap from the cylindrical portion, surrounds the cylindrical portion, and is curved on the inner surface of the reflecting member. is a reflecting surface that reflects the light of the discharge tube,
Brackets are fixed to the left and right sides of the discharge tube extending in the left and right direction in the housing,
Each of the brackets is provided with an insulator, and the insulators are arranged on the right and left sides above the discharge tube,
The trigger conductive part is a trigger wire formed of a metal wire,
The trigger conductive portion is wound around the outer peripheral surface of the cylindrical portion and is arranged radially outward of the cylindrical portion,
Left and right lead wires provided at both ends of the trigger wire are stretched between the trigger wire and the insulator so as to pull both ends of the trigger wire wound around the cylindrical portion. flaw detector.
The interior of each of the holding parts includes a water communication part that communicates with the insertion space,
The water communicating portion has one end communicating with the insertion space and the other end communicating with the outside of the holding portion,
The cooling liquid is introduced into the channel from the water communicating portion of one of the holding portions, and the cooling liquid is discharged from the channel through the water communicating portion of the other holding portion. ,
The cooling unit includes a tank that supplies the cooling liquid, a pump that circulates the cooling liquid, a chiller, and a temperature sensor connected to a computer,
A hose for introduction is connected to the water communication portion of one of the holding portions, and the hose for introduction is connected to the tank,
A discharge hose is connected to the water communication part of the other holding part, the discharge hose is also connected to the tank, and the recovered cooling liquid is stored in the tank again,
The pump has a capacity according to the flow rate of the cooling liquid and the flow rate of the cooling liquid, corresponding to the characteristics and heating energy of the discharge tube,
the pump is separate from the chiller or provided with the chiller;
The temperature sensor is provided in at least one of the tank, the introduction hose, and the discharge hose, and warns the computer when the temperature rises above a predetermined level, or automatically activates the cooling device of the chiller. 2. The flaw detector according to claim 1, wherein the temperature of the cooling liquid is adjusted by rotating the cooling liquid.
The reflecting member includes a sub-reflecting portion disposed on the opposite side of the test material across the tubular portion, and a main reflecting portion disposed closer to the test material than the sub-reflecting portion,
The sub-reflecting part has a reflecting surface that reflects the light received from the discharge tube toward the test material and the main reflecting part,
The main reflecting portion has a reflecting surface that reflects the light directly received from the discharge tube and the light reflected by the sub-reflecting portion toward the test material,
The main reflection portion includes a first main reflection portion and a second main reflection portion,
The first main reflection portion and the second main reflection portion have their reflection surfaces facing each other, and the light traveling from the discharge tube to the test material is between the first main reflection portion and the second main reflection portion. through
3. The flaw detection according to claim 1, wherein the distance between the reflecting surface of the first main reflecting portion and the reflecting surface of the second main reflecting portion is gradually widened from the side of the sub-reflecting portion toward the side of the material to be tested. Device.
The sub-reflection portion is formed separately from the main reflection portion,
4. A contour projected onto a plane perpendicular to the longitudinal direction of the discharge tube, for at least the reflecting surfaces of the first main reflecting portion and the second main reflecting portion, is a part of a parabola. flaw detector.
The first main reflection portion extends from one end of the sub-reflection portion and is continuous with the sub-reflection portion,
the second main reflection portion extends from the other end of the sub-reflection portion and is continuous with the sub-reflection portion;
The reflecting surface of each of the first main reflecting portion and the second main reflecting portion and the reflecting surface of the sub-reflecting portion are projected onto a plane perpendicular to the longitudinal direction of the discharge tube, and the contours of the reflecting surfaces project a continuous parabola. The flaw detector according to claim 3.
The image acquisition device acquires an image by infrared thermography with an infrared camera,
The discharge tube is a xenon lamp,
The tubular portion is a quartz tube,
The cooling unit includes a chiller that circulates the cooling liquid,
The heating device includes a holding portion that holds both ends of the discharge tube together with the cylindrical portion,
The heating device comprises a base on which the holding part and the main reflecting part are attached,
the housing supports the main reflecting portion and the base is detachably attached to the housing;
The housing accommodates at least the discharge tube, the cylindrical portion, the trigger conductive portion, the holding portion, and the sub-reflection portion,
By removing the base from the housing, the main reflecting portion remains in the housing, and the discharge tube, the cylindrical portion, the trigger conductive portion, the holding portion, and the sub-reflecting portion are integrated to form the 5. The flaw detector according to claim 4, which can be removed from the housing.

Images