JPH11166910A - Infrared image inspecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infrared image inspecting device capable of inspecting defect parts such as cavities, cracks, present in an object even in a complicated shape and easily obtaining satisfactory detectability. SOLUTION: An infrared image inspecting device is constituted of a placing platform of an object to be inspected, a plurality of sensors 15 to measure distances to the object to be inspected, a heater 54 to heat the object to be inspected, an infrared camera 51, an infrared image signal processing displaying device 52, and a controller 10 to control these instrument. The location of placement and the angle of placement of the object to be inspected are adjustable in the placing platform, and the sensors 15 are movable vertically with respect to the direction of observation of the infrared camera 51. From measured values by the distance sensors 15, etc., the location and the inclination of the object are indicated by a controller 10, and an inclining and rotating table, etc. are operated by the controller 10 to control the movement and the inclination of the object on the placing platform. Therefore, it is possible to inspect an object even in a distorted shape properly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Cavities inherent in various structures,
The present invention relates to an infrared image inspection device for inspecting a defect such as a crack.

[0002]

2. Description of the Related Art An outline of a conventional infrared image inspection apparatus will be described with reference to FIG.

An infrared camera 51 senses infrared rays emitted from various positions of an object and outputs a voltage (or current) corresponding to the intensity of the infrared rays as a video signal. Reference numeral 172 denotes an inspection target, which indicates a part of a structure to be inspected, and reference numeral 73 denotes a cavity existing in the inspection target 172.

[0004] Reference numeral 54 denotes a heater, which is provided in a pair on the left and right front toward the object 172, and heats the object 172.

Reference numeral 52 denotes an infrared video signal processor, which communicates with the infrared camera 51 via a cable 61, receives a signal from the infrared camera 51 which outputs infrared intensity as a video signal, and displays it on a display unit 53.

A controller 110 communicates with the infrared video signal processor 52 via a cable 62 and the controller 110 via a cable 63 to control the operation of these devices.

Reference numeral 20 denotes a start button attached to the panel surface of the controller 110, and reference numeral 111 denotes a table on which the object 172 is installed.

If the cavity 73 is present inside the object 172 which is a component of the structure, there is a problem in the strength of the structure. Therefore, it is desired to inspect the presence or absence of this by some method. .

In the apparatus shown in FIG.
Numeral 4 is configured to heat the outer surface of the object 172 for a predetermined fixed time width only when the operator presses the start button 20 of the controller 110.

[0010] The controller 110 supplies electric power for heating to the heater 54 at a predetermined fixed time width when the operator presses the start button 20, and also controls the infrared video signal processor 52 at appropriate timing. Is configured to transmit an actuation signal to the controller.

The infrared video signal processor 52 receives a signal from the controller 110, fetches an infrared video signal from the infrared camera 51, and displays it on the display unit 53 as a predetermined video.

The infrared camera 51 is arranged so as to face a portion of the object 172 to be inspected, and the portion to be inspected is displayed as an appropriate image on the display unit 53. And outputs a video signal of a voltage (or current) corresponding to the intensity of infrared rays radiated from the camera.

According to Stefan-Boltzmann's law,
An object always emits infrared light having an intensity corresponding to the temperature of the object from its surface, and the intensity of the emitted infrared light increases as the temperature of the object increases.

Now, when the outer surface of the object 172 is uniformly heated, each point near the surface of the object 172 attempts to uniformly increase the temperature and transfers heat toward the center of the object 172. Then, the temperature of each point near the surface starts to decrease.

In addition, since solids and gases have a higher thermal conductivity and a hollow portion has a lower thermal conductivity, the temperature of each point in the vicinity of the surface adjacent to the cavity is lower than the temperature per unit time. The degree of decline is slow.

Therefore, when the periphery of the cavity 73 of the object 172 is to be inspected, if the outer surface of this portion is uniformly heated, at the moment of heating and within a short time range after heating, The temperature of the outer surface of the adjacent portion of the cavity 73 is higher than the other portions.

When the temperature of the outer surface rises, the temperature of the infrared rays radiated from each point rises, and the infrared camera 51 senses the infrared rays with high intensity from the outer surface of the high temperature portion. Since the processing is performed and displayed on the display unit 53, the operator observes the high-temperature portion on the outer surface of the object 172 based on the processing and displays the internal cavity 7.
3 can be identified and confirmed.

The detection sensitivity is determined by the magnitude of the heating energy,
Depending on the timing of heating and observation, the object 17
The distance between the heater 2 and the heater 54 is kept constant, and the time relationship between heating and observation (data acquisition) is also carefully considered.

The controller 110 functions to keep the time relationship between heating and observation constant. When the operator presses the start button, the controller 110 activates the heater 54 and sends a signal to the infrared image signal processor 52. , And also process and display the data.

When the object 172 has a cylindrical shape or the like as shown in FIG. 4, it is difficult to inspect the entire surface by one observation, and the operator rotates the object 172 slightly by hand. Heating and observation are performed, and heating and observation are repeated with a slight rotation to inspect the entire surface. And object 1
Each time the 72 is rotated, the operator checks the distance between the heater 54 and the object 172 by using a measure or the like.

In order to improve the detection accuracy of the cavity 73,
The outer surface of the object 172 needs to be heated as uniformly as possible. For this reason, a plurality of heaters 54 are used as in the example shown in FIG.

FIG. 5 shows an image of the display unit 53 of the infrared image signal processor 52 obtained around the cavity 73 of the object 172 and the horizontal direction of the display unit 53 at that time in the example shown in FIG. And the temperature distribution in the vertical direction.

In FIG. 5, (a) shows the shape 134 of the object 172 obtained as an infrared image, and the portion 33 where the temperature is displayed high within the displayed object shape 134 is shown. Is shown. Reference numeral 53 is the same display unit as the display unit 53 shown in FIG.

(B) shows the vertical temperature distribution that can be read from the object 172 by the infrared image at the position Xb, and (c) also shows the horizontal temperature distribution at the position Ya.

As shown in this figure, when heating, data acquisition, etc. are performed satisfactorily, the cavity 73 appears as a portion where the temperature is displayed high in the shape 134 of the object of the display unit 53, and other portions appear. The display temperature of the portion is uniform, and the cavity 73
Can be clearly detected.

As described above, the inspection method using infrared rays shown in FIGS. 4 and 5 can detect a defective portion such as a harmful cavity in the material of the inspection object which cannot be visually identified, and is practically effective. , Is widely applied in industrial field.

[0027]

However, the above-mentioned conventional inspection apparatus using infrared rays has the following problems.

That is, if the object is not a simple cylindrical one as shown in FIG. 4, but has a complicated shape, uniform heating cannot be obtained. Even if this is a sound object, At the time of heating, a difference occurs in the temperature of each part of the outer surface, and it becomes difficult to clearly detect a cavity or the like.

In addition, in order to obtain a uniform heating state and enhance the detectability, the operator adjusts the installation angle of the object, performs heating and observation, and repeats the above to obtain an optimum state, and then inspects the object. This adjustment requires a great deal of time.

An object of the present invention is to provide an inspection apparatus which solves the above-mentioned disadvantages of the prior art, and which can easily obtain good detectability even for an object having a complicated shape. It is.

[0031]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has an installation table for an inspection object, a plurality of sensors for measuring a distance from the inspection object, and heating of the inspection object. A heater, an infrared camera, an infrared image signal processing display, and a controller for controlling these devices, the installation table is configured to be able to adjust an installation position and an installation angle of the inspection object, and the sensor is It is an object of the present invention to provide an infrared image inspection apparatus configured to be movable in a direction perpendicular to the observation direction of the infrared camera.

That is, since the infrared image inspection apparatus of the present invention is configured as described above, each point of the object at the moving position and each sensor are moved while the plurality of distance sensors move perpendicularly to the observation direction of the infrared camera. The distance between the objects is measured, and the position and inclination of the object are obtained by the controller from the measured values.
By operating the direction rail and the tilt / rotation table, etc., the movement and tilt of the installation table of the object are controlled, and the position and inclination of the object on the installation table are made appropriate, so that trial and error by the operator is not required. Thus, workability is improved.

[0033]

FIG. 1 shows an embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 shows a conceptual configuration of the infrared image inspection apparatus according to the present embodiment, FIG. 2 shows an operation flow of a controller which controls the apparatus of FIG. 1, and FIG.
Indicates inspection data of the object.

The same parts as those of the prior art described above are denoted by the same reference numerals in the drawings, and overlapping descriptions are omitted as much as possible to simplify the whole description.

Reference numeral 11 denotes a tilt / rotation table, and 12 denotes a tilt / rotation table.
A rotating rail, 13 is an X-direction moving rail, 14 is a Y-direction moving rail, and the X-direction moving rail 13 is installed on the Y-direction moving rail 14.
It is installed on the direction moving rail.

Since the tilting / rotating table 11 is set on the tilting / rotating rail 12, the tilting / rotating table 11 includes a Y-direction moving rail 14, an X-direction moving rail 13, and a tilting / rotating rail. By actuating 12, it is possible to move, rotate and tilt to any position within a certain range.

Reference numeral 15 denotes a pair of distance measuring sensors vertically separated from each other, 17 denotes a moving arm on which the distance measuring sensor 15 is mounted, and 18 denotes an X-direction moving rail on which the moving arm 17 is mounted. The actuation of 18 causes the movement arm 17 to move in the X direction.

An angle setting dial 30 and a start button 2 are provided on the outer surface of the controller as input means.
0 and the like are arranged. The angle dial 30 of the controller 10 is for setting an angle at which the inspection of the object is desired.

Cables 21 and 22 are cables 21
Is a cable 2 between the controller 10 and the moving arm 17.
Numeral 2 communicates between the controller 10 and the X-direction moving rail 18, the Y-direction moving rail 14, the X-direction moving rail 13, and the tilt / rotation rail 12.

The infrared camera 51, the infrared video signal processor 52, the display unit 53, the heater 54, the cable 61,
Since 62, 63, etc. are the same as the above-mentioned conventional ones, further description is omitted.

Reference numeral 72 denotes an irregularly shaped inspection object, which is placed on the tilt / rotation table 11 so as to face the distance measuring sensor 15. 73 is the object 72
Is an internal cavity.

As described above, in order to obtain good detectability, it is necessary to uniformly heat the portion of the outer surface of the object to be inspected. It is desired that the surface to be inspected of the object be as perpendicular to the infrared rays from the heater as possible. Further, in order to inspect the entirety of the object 72, it is necessary to rotate the object 72 little by little, perform heating each time, and observe an infrared image.

In the present embodiment configured as described above, first, in the initial state, the moving arm 17 to which the distance sensor 15 is attached is disposed at the left end of the X-direction moving rail 18 (outside the observation range of the infrared camera). .

The operator sets the angle setting dial 30
Is operated to set the angle at which the inspection is desired, and then the start button 20 is pressed. Then, the controller 10 operates the tilt / rotation rail 12 and the tilt / rotation table 11
Is rotated by the designated angle, and then the X-direction moving rail 18 is rotated.
Operates, the two distance sensors 15, 15 operate while the moving arm 17 moves in the X direction.
The position in the direction and data measured by the two distance sensors 15 are taken into the controller 10.

The distance measuring sensor 15 has a function of instantaneously measuring the distance between a relatively small target point and the sensor, and the two distance measuring sensors 15 and 15 measure while moving in the X direction. The distance data is a value determined by the shape of the object 72, the installed position, the inclination, and the like. That is, the distance between the object 72 and the heater 54, the inclination of the surface to be inspected of the object 72, and the like are obtained from the measurement data.

In order to obtain good detectability, the object 72
The position and inclination of the surface to be inspected are important, and the controller 10 internally sets the X-direction to obtain an appropriate position and inclination from the distance measurement data obtained by the two distance measurement sensors 15 at each X-direction position. , The correction values of the Y direction and the inclination are calculated, the inclination / rotation rail 12, the X direction movement rail 13 and the Y
The direction moving rail 14 is operated to make the position and inclination of the inspection surface of the object 72 appropriate. The moving arm 17
Moves rightward while measuring the distance, then immediately moves leftward and stops at the initial position (left end).

After the position and the inclination of the surface to be inspected of the object 72 are properly adjusted, the controller 10
As in the case of 10, the heater 54 is operated, and at the same time, a signal is sent to the infrared image signal processor 52 to take in data and to perform processing and display.

The above-described series of operations proceeds according to a command from the controller 10, and the operation flow of the controller 10 is shown in FIG. That is, the controller 10 controls the flow of the work described above, and the object 72 is rotated little by little, heated each time, and observed by displaying an infrared image.

FIG. 3 shows an example of inspection data according to the present embodiment obtained through the above process. 3, (a) is an image of the display unit 53 of the object 72 obtained as an infrared image, (b) is a vertical temperature distribution at the position Xb, and (c) is a horizontal direction at the position Ya. 3 shows the temperature distribution.

As shown in FIG.
Even if the shape is irregular, in order to make the position and inclination of the surface to be inspected appropriate by the operation of the controller 10 and each mechanism, the target object 72 based on the displayed infrared image is
As shown in each graph, the temperature fluctuation is small in both the vertical and horizontal directions, and the portion corresponding to the cavity 73 is clearly identified as the portion 33 where the temperature is displayed higher.

Although the present invention has been described with reference to the illustrated embodiments, the present invention is not limited to such embodiments.
It goes without saying that various changes may be made to the specific structure within the scope of the present invention.

[0052]

As described above, according to the present invention, the infrared image inspection apparatus comprises a mounting table for the inspection object, a plurality of sensors for measuring the distance to the inspection object, and a heater for heating the inspection object. , Infrared camera, infrared video signal processing display,
And a controller that controls these devices, and the installation table is configured to be able to adjust an installation position and an installation angle of the inspection object, and the sensor can be moved perpendicularly to an observation direction of the infrared camera. Because the distance sensors move perpendicular to the observation direction of the infrared camera, the distance sensors measure the distance between each point of the object and each sensor at the movement position, and the controller uses the measured values to calculate the distance between the sensors. Position and tilt are obtained.
For example, by operating the X-direction rail, the Y-direction rail, the tilt / rotary table, and the like to control the movement and tilt of the mounting table of the object, and to make the position and tilt of the object on the mounting table appropriate, Since the position and inclination of the surface to be inspected can be properly maintained even for shaped objects, inspection with excellent discrimination can be performed in a short time, and workability is improved, such as eliminating the need for trial and error by the operator. As a result, a device having excellent practicality was obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of an inspection device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an operation flow of a controller in the embodiment of FIG. 1;

FIG. 3 shows an example of inspection data according to the embodiment of FIG. 1,
(A) is an image on a display unit, (b) is a vertical temperature distribution at a position Xb, and (c) is a horizontal temperature distribution at a position Ya.

FIG. 4 is an explanatory diagram showing a configuration of a conventional inspection device.

FIG. 5 shows an example of inspection data by a conventional inspection device,
(A) is an image on a display unit, (b) is a vertical temperature distribution at a position Xb, and (c) is a horizontal temperature distribution at a position Ya.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Controller 11 Inclination / rotation table 12 Inclination / rotation rail 13 X-direction moving rail 14 Y-direction moving rail 15 Distance measuring sensor 17 Moving arm 18 X-direction moving rail 20 Start button 21 Cable 22 Cable 30 Angle setting dial 33 High temperature display Part to be displayed 34 shape of the displayed object 51 infrared camera 52 infrared video signal processor 53 display unit 54 heater 61 cable 62 cable 63 cable 72 target 73 cavity

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuo Araki 2-1-1, Shinhama, Arai-machi, Takasago-shi, Hyogo Prefecture Inside the Takasago Research Laboratory, Mitsubishi Heavy Industries, Ltd. No. 1 Inside Mitsubishi Heavy Industries, Ltd. Takasago Works (72) Inventor Yoshiyuki Nishiguchi 2-1-1, Shinhama, Araimachi, Takasago City, Hyogo Prefecture Inside Takasago Works, Mitsubishi Heavy Industries, Ltd.

Claims (1)

[Claims] 1. An installation table for an object to be inspected, a plurality of sensors for measuring the distance to the object to be inspected, a heater for heating the object to be inspected, an infrared camera, an infrared image signal processing display, and control of these devices The installation table is configured to be able to adjust the installation position and the installation angle of the inspection object, and the sensor is configured to be movable vertically to the observation direction of the infrared camera. Infrared image inspection device.