KR20230027306A - Ultrasonic inspection device, support inspection method, and support inspection program - Google Patents

Abstract

An ultrasonic inspection device (A) for inspecting a support at least partially formed of a metal member used for producing a film, wherein an ultrasonic probe (2) is used to transmit ultrasonic waves into the metal support through a contact medium, and When the inside of the support is ultrasonically scanned by the transmitting/receiving unit 11 for receiving an ultrasonic echo from the inside of the support and the ultrasonic probe 2, based on the ultrasonic echo detected at each scanning position, a tomographic image within the support is generated. The tomographic image generation unit 12 and the tomographic image are image-analyzed, and the layered image is expressed in the tomographic image due to multiple reflections between the upper and lower surfaces of the metal member of the support body of the ultrasonic wave transmitted from the ultrasonic probe 2 An ultrasonic inspection apparatus (A) provided with an evaluation unit (13) that evaluates the state of the inside of the support body based on the aspect of .

Description

Ultrasonic inspection device, support inspection method, and support inspection program

The present disclosure relates to an ultrasonic inspection device, a support inspection method, and a support inspection program.

When manufacturing a film, metal support bodies (henceforth a "metal support body"), such as a belt and a drum for supporting a film, are used. For example, when producing polymer films widely used in polarizing plates and electronic displays (eg, solution film forming method), belts and drums are used to support raw materials in the initial drying step of the film, and post-drying is performed. For the conveyance of films, etc., conveyance rolls are used.

Japanese Patent Publication No. 2016-517494 Japanese Unexamined Patent Publication No. 2007-083451 Japanese Unexamined Patent Publication No. 11-051910

However, it is known that the presence of defects (hereinafter referred to as “defects”) such as scratches, stains, or pinholes (i.e., holes) on the surface of a metal support will cause deterioration in the quality of the film produced (for example, For example, Patent Document 1 and Patent Document 2). In particular, in the solution film forming method of producing a film by casting a polymer solution from a slit die onto a support such as a drum, a belt, and a carrier film to form a sheet, and drying a solvent from the resulting sheet film, a metal support ( Here, pinhole defects tend to occur on the surface of the film due to defects existing on the surface of the drum and belt).

From this background, conventionally, in the manufacturing facilities of this type of film, the surface of the metal support is regularly inspected, and when a defect is detected on the surface of the metal support in the inspection, the metal support is repaired by polishing or the like. process is being carried out.

In this type of film production facility, the film production line is stopped during inspection and repair of the metal support, so from the viewpoint of productivity improvement, it is necessary to complete the inspection step to the repair step in a short time. In this respect, when voids (namely, voids) or foreign substances exist inside the metal support, it becomes a problem that new defects are generated on the surface of the metal support during repair. This is because when a new defect occurs on the surface of the metal support while the metal support is being repaired, the repair step is prolonged or a state in which the repair step is repeatedly performed occurs, leading to a decrease in productivity.

Therefore, in order to prevent deterioration in film quality and deterioration in productivity, it is necessary to introduce a metal support having low defect occurrence. In addition, it is indispensable to be able to predict the state after the repair step in advance. In particular, since this kind of metal support is placed in a state where a large pressure is applied along with the bending process at the time of manufacturing the metal support, its internal structure (for example, crystal structure) changes over time, Eventually, it will contain many voids and foreign matter. Therefore, it is preferable to be able to evaluate the internal state of the metal support with high accuracy to the extent that the lifetime of the metal support can be predicted at the time of inspection of the metal support or before mounting the metal support to the film production facility.

The present disclosure has been made in view of the above problems, and aims to provide an ultrasonic inspection device capable of highly accurately evaluating the state of the inside of a support used for film production, a support inspection method, and a support inspection program. to be

The main present disclosure to solve the above problems is,

An ultrasonic inspection device for inspecting a support at least partially formed of a metal member used to manufacture a film, comprising:

a transmission/reception unit that transmits ultrasonic waves into the support body through a contact medium using an ultrasonic probe and receives an ultrasonic echo from the inside of the support body;

a tomographic image generating unit that generates a tomographic image of the support based on the ultrasonic echo detected at each scanning position when the inside of the support is scanned by ultrasonic probe with the ultrasonic probe;

The tomographic image is image analyzed, and based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between the front and back surfaces of the metal part of the support of the ultrasonic wave transmitted from the ultrasonic probe, the support Evaluation unit that evaluates internal conditions

It is an ultrasonic inspection device having a.

Also, in another aspect,

As an inspection method for inspecting a support used to manufacture a film,

processing using an ultrasonic probe to transmit ultrasonic waves into the support body through a contact medium and receive ultrasonic echoes from inside the support body;

a process of generating a tomographic image of the support based on the ultrasonic echo detected at each scanning position when ultrasonic scanning of the inside of the support with the ultrasonic probe;

The tomographic image is image analyzed, and based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between the front and back surfaces of the metal part of the support of the ultrasonic wave transmitted from the ultrasonic probe, the support A process that evaluates the state of the internal

It is a test method with

Also, in another aspect,

As an inspection program for inspecting a support used to manufacture a film,

processing using an ultrasonic probe to transmit ultrasonic waves into the support body through a contact medium and receive ultrasonic echoes from inside the support body;

a process of generating a tomographic image of the support based on the ultrasonic echo detected at each scanning position when ultrasonic scanning of the inside of the support with the ultrasonic probe;

The tomographic image is image analyzed, and based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between the front and back surfaces of the metal part of the support of the ultrasonic wave transmitted from the ultrasonic probe, the support A process that evaluates the state of the internal

It is a test program with

According to the ultrasonic inspection apparatus according to the present disclosure, it is possible to accurately evaluate the state of the inside of the support used for film production.

1 is a diagram showing an example of the appearance of an ultrasonic inspection apparatus according to an embodiment.
2 is a diagram showing an example of the configuration of an ultrasonic inspection apparatus according to an embodiment.
Fig. 3 is a diagram showing an example of an arrangement formation state of ultrasonic probes included in an ultrasonic inspection apparatus according to an embodiment.
4 is a tomographic image observed when the uniformity of the internal structure of the metal support is high.
Fig. 5 is a tomographic image observed when the uniformity of the internal structure of the metal support is lowered due to the change over time of the metal support.
Fig. 6 is an enlarged view of the layered image area in Fig. 5;
Fig. 7 is a diagram explaining the principle of displaying a layered image in a tomographic image.
Fig. 8 is a diagram showing a change in luminance values in the depth direction of the layered images of Figs. 4 and 5;
Fig. 9 is a diagram showing a change in the luminance value in the transverse direction (ie, the in-plane direction of the metal support) of the layered image in each of Figs. 4 and 5;
10 is a flowchart showing an example of the operation of the ultrasonic inspection device.

EMBODIMENT OF THE INVENTION Preferred embodiment of this indication is described in detail, referring an accompanying drawing below. In this specification and drawings, components having substantially the same functions are denoted by the same reference numerals, and redundant explanations are omitted.

[Configuration of Ultrasonic Inspection Device for Metal Support]

Hereinafter, with reference to FIGS. 1-4, the structure of the ultrasonic inspection apparatus which concerns on one embodiment is demonstrated. In addition, the ultrasonic inspection device according to the present embodiment is used to inspect the internal state of a support used in a film manufacturing facility, particularly the uniformity of the internal structure of the support.

1 is a diagram showing an example of the external appearance of an ultrasonic inspection device (A). Fig. 2 is a diagram showing an example of the configuration of an ultrasonic inspection device (A). Fig. 3 is a diagram showing an example of an arrangement formation state of the ultrasonic probes 2 included in the ultrasonic inspection apparatus A.

The ultrasonic inspection device (A) according to the present embodiment is an inspection device that inspects, for example, a metal belt (hereinafter referred to as "metal support (C)") used in a film manufacturing facility by a solution film forming method. am. The metal support body C is formed of, for example, a stainless steel metal plate having a first surface Ca and a second surface Cb that are in a mutually front-back relationship. In addition, in FIG. 3, the 1st surface Ca of the metal support body C is the surface of the side facing the ultrasonic transmission/reception surface of the ultrasonic probe 2. Moreover, when the 2nd surface (Cb) of the metal support body (C) is attached to the manufacturing facility of the said metal support body (C) of a film, it is the surface of the side (the side which abuts against a film) which conveys a film.

However, the support object to be inspected by the ultrasonic inspection apparatus A is not limited to a support body entirely composed of a metal material, such as a metal plate, and may be one in which a metal member is formed on the surface of a support body composed of an insulating material by plating or the like. do. In that case, the object of inspection by the ultrasonic inspection device A is the internal structure of a metal member formed on the surface of a support made of an insulating material.

An ultrasonic inspection device (A) is configured by attaching an ultrasonic probe (2) to an ultrasonic inspection device main body (1). In addition, the main body 1 and the ultrasonic probe 2 are electrically connected via a cable. The ultrasonic inspection apparatus (A) uses ultrasonic waves to visualize the state inside the metal support body (C), thereby evaluating the state inside the metal support body (C).

The ultrasonic probe 2 controls a plurality of piezoelectric vibrators (here, 256 piezoelectric vibrators) 21 that mutually convert ultrasonic waves and electric signals, and turns on/off the driving state of each of the plurality of piezoelectric vibrators 21. It is configured to include a channel switching unit (not shown) for individually switching control. Then, the plurality of piezoelectric vibrators 21 individually convert the voltage pulses generated in the ultrasonic inspection apparatus body 1 (transmitter/receiver unit 11) into ultrasonic beams and transmit the ultrasonic beams into the metal support body. An ultrasonic echo generated by reflection of a beam within a metal support is received, converted into an electrical signal, and output to the main body 1 (transmitter/receiver 11) of the ultrasonic inspection device.

A plurality of piezoelectric vibrators 21 are arranged in an array form, for example, along the scanning direction. Further, switching control is performed to turn on/off the driving state of the plurality of piezoelectric vibrators 21 individually or in block units in order along the scanning direction. In this way, in the ultrasonic probe 2, transmission and reception of ultrasonic waves is performed so as to scan the inside of the metal support body C.

The ultrasonic probe 2 is arranged so that the ultrasonic transmitting/receiving surface is in contact with the first surface Ca of the metal support C through the contact medium B. The contact medium (B) enables transmission focus by forming a space between the ultrasonic transmission/reception surface of the ultrasonic probe 2 and the first surface (Ca) of the metal support (C), and further prevents an air layer from intervening. Here, as the contact medium (B), an echo gel pad (B1) mounted on the ultrasonic transmission/reception surface of the ultrasonic probe (2), an echo gel pad (B1) and a metal support (C) A gel (B2) interposed between the first surfaces (Ca) is disposed. In addition, the contact medium (B) may be omitted depending on the degree of influence of the disturbance when transmitting from the ultrasonic probe 2 to the metal support body (C).

The ultrasonic inspection device main body 1 includes a transmission/reception unit 11, a tomographic image generation unit 12, an evaluation unit 13, and a notification unit 14.

The transmission/reception unit 11 is a transmission/reception circuit that transmits/receives ultrasonic waves to the piezoelectric vibrator 21 of the ultrasonic probe 2.

The transmission/reception unit 11 includes a transmission unit 11a that generates a voltage pulse (hereinafter referred to as a "drive signal") and transmits it to the piezoelectric vibrator 21, and electricity related to the reception beam generated by the piezoelectric vibrator 21. It has a receiving section 11b that receives and processes a signal (hereinafter referred to as a "received signal").

The transmission unit 11a is configured to include, for example, a pulse oscillator and a pulse setting unit formed for each channel connected to the piezoelectric vibrator 21 . The transmitter 11a adjusts the voltage pulse generated by the pulse oscillator to the voltage amplitude, pulse width, and timing set in the pulse setting unit, and sends it to the piezoelectric vibrator 21 .

In addition, the transmitter 11a transmits a drive signal to the piezoelectric transducer 21 so that an ultrasonic beam is transmitted from the piezoelectric transducer 21 of the ultrasonic probe 2 . The ultrasonic beam transmitted by the transmitter 11a preferably includes a plurality of frequency components (eg, 1 MHz to 20 MHz). This makes it possible to transmit and receive wideband signals, and to generate high-definition images.

The receiver 11b is constituted by, for example, a preamplifier, an AD converter, and a receive beamformer. A preamplifier and an AD converter are formed for each channel connected to the piezoelectric transducer 21, amplify a weak received signal, and convert the amplified received signal (analog signal) into a digital signal. The reception beamformer gathers the received signals of a plurality of piezoelectric transducers 21 into one by adding the received signals (digital signals) of each piezoelectric transducer 21 into one, and outputs it to the tomographic image generating unit 12.

The tomographic image generation unit 12 acquires a received signal at each scanning position output from the transmission/reception unit 11, sequentially stores the received signal in a line memory, and generates two-dimensional data in units of frames. In addition, the two-dimensional data is constituted by signal strength information at each position in the cross section of the metal support along the scanning direction and the depth direction. Then, the tomographic image generation unit 12 generates image data related to the tomographic image based on the two-dimensional data. The tomographic image generation unit 12 converts, for example, sampling data (e.g., the signal intensity of a received signal) at each position in a cross section along the scanning direction and the depth direction into pixel values, so that one frame Create a tomographic image.

The evaluation unit 13 performs image analysis on the tomographic image generated by the tomographic image generating unit 12, and transmits ultrasonic waves sent from the ultrasonic probe 2 between the front and back surfaces of the metal support C (here, the first surface Based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between (Ca) and the second surface (Cb), the state of the inside of the metal support (C) is evaluated.

The notification unit 14 is, for example, a monitor, and outputs the evaluation result by the evaluation unit 13. The notification unit 14 notifies the user, for example, when the evaluation result of the evaluation unit 13 indicates that the internal structure of the metal support C is defective.

[Detailed composition of evaluation department]

Here, details of the configuration of the evaluation unit 13 will be described.

4 and 5 are tomographic images observed when ultrasonic scanning is performed on the same metal support (C). 4 is a tomographic image observed when the uniformity of the internal structure of the metal support (C) is high, and FIG. ) is a tomographic image observed when the uniformity of the internal structure of . FIG. 6 is an enlarged view of the layered image region R1 in FIG. 5 .

Areas with high luminance in FIGS. 4 and 5 indicate areas with high ultrasonic echo signal strength. P1 in FIGS. 4 and 5 is a layered image expressed in a tomographic image due to multiple reflections between the first surface (Ca) and the second surface (Cb) of the metal support (C), here, about 15 layers A layered image drawn to be layered is being displayed.

In addition, in the linear high luminance regions P2a and P2b in FIGS. 4 and 5 , the ultrasonic wave transmitted from the ultrasonic probe 2 is reflected on the first surface Ca of the metal support C, respectively, and the ultrasonic probe It is the luminance component resulting from the surface reflected wave returning to the ultrasonic transmission/reception surface of (2). Here, the high luminance region P2a is a luminance component derived from the surface reflected wave observed for the first time (hereinafter referred to as "the first surface reflected wave"), and the high luminance region P2b is the first surface reflected wave detected by the ultrasonic probe ( 2) After being reflected on the ultrasonic transmission/reception surface of the ultrasonic probe 2, it is reflected again on the first surface Ca of the metal support C and returns to the ultrasonic transmission/reception surface of the ultrasonic probe 2 (hereinafter referred to as “second surface reflected wave”) ) is a luminance component originating from

Fig. 7 is a diagram explaining the principle of displaying a layered image in a tomographic image.

Ultrasound transmitted from the ultrasonic probe 2 and penetrating into the metal support C travels from the first surface Ca of the metal support C to the second surface Cb. And the said ultrasonic wave is reflected by the 2nd surface (Cb) of the metal support body (C), and goes to the 1st surface (Ca) of the metal support body (C) again. Then, when the ultrasonic wave reaches the first surface (Ca) of the metal support (C), a part of it proceeds into the contact medium (B) and returns to the ultrasonic probe (2), and the other part is transmitted to the metal support (C). is reflected again on the first surface (Ca) of the metal support (C) and proceeds from the first surface (Ca) toward the second surface (Cb).

Since the ultrasonic wave penetrating into the metal support body (C) is reflected multiple times between the first surface (Ca) and the second surface (Cb) of the metal support body (C), the ultrasonic wave penetrates the first surface of the metal support body (C). In the process of multiple reflection between the surface Ca and the second surface Cb, whenever it reaches the first surface Ca of the metal support C, a part thereof is detected by the ultrasonic probe 2. At this time, the repeatedly detected ultrasonic echoes become a layered image drawn so as to be stacked along the depth direction, and are expressed in a tomographic image (Rall in the lower drawing of FIG. 7). In addition, the thickness of each layer in this layered image (d1 in the lower drawing of FIG. 7 ) corresponds to the propagation time of the ultrasonic wave between the first surface Ca and the second surface Cb of the metal support C That is, it corresponds to the distance (d1 in the upper drawing of Fig. 7) between the first surface Ca and the second surface Cb of the metal support body C.

In addition, the image of the layer appearing on the lower layer side of the layered image P1 in the tomographic image is an ultrasonic echo after repeated multiple reflection between the first surface Ca and the second surface Cb of the metal support C ( That is, since the ultrasonic echo attenuated in the metal support (C) was detected in the process of multiple reflection, the luminance is reduced compared to the image of the layer appearing on the upper layer side of the layered image (P1) in the tomographic image. there is. In addition, multiple reflections in the metal support body (C) of the ultrasonic waves penetrating into the inside of the metal support body (C) occur, in many cases, on the order of hundreds of times.

Here, the layered image in the tomographic image which the evaluation part 13 makes into an analysis object is demonstrated.

When the evaluation unit 13 evaluates the internal state of the metal support body C, for example, the ultrasonic waves transmitted from the ultrasonic probe determine the first surface Ca and the second surface Cb of the metal support body C. ) Among the signal components detected in the process of multiple reflection between, only the signal components detected after the first surface reflected wave is detected and until the second surface reflected wave is detected (in FIGS. 4 and 5, P2a and A layered image (P1) of about 15 layers exposed between P2b is set as an analysis target. In this way, a situation in which the signal component derived from the surface reflected wave overlaps with the signal component of the ultrasonic echo from the inside of the metal support C is suppressed.

The speed of sound of ultrasonic waves is generally based on the propagation medium (speed of sound = √(modulus of elasticity/density)). For example, the speed of sound of ultrasonic waves propagating in stainless steel is about 4 times the speed of sound of ultrasonic waves propagating in water. do. Therefore, after the first surface reflected wave (ie, P2a in FIGS. 4 and 5 ) is detected, until the second surface reflected wave (ie, P2b in FIGS. 4 and 5 ) is detected, the metal support Ultrasonic echoes from the inside of the metal support (C) resulting from multiple reflected waves generated between the first surface (Ca) and the second surface (Cb) of (C) are detected multiple times.

At this time, in the tomographic image, between the high luminance region P2a expressed due to the first surface reflected wave and the high luminance region 9P2b expressed due to the second surface reflected wave, by the following formula (1) A layered image P1 of the calculated number of layers (here, a layered image of about 15 layers) is observed. Equation (1) represents the number of multiple reflections occurring between the first surface (Ca) and the second surface (Cb) of the metal support (C) while the surface reflection wave reciprocates through the contact medium (B) once. there is.

(However, d1: thickness of metal support (C), d2: thickness of contact medium (B), v1: sound speed in metal support (C), v2: sound speed in contact medium (B))

From this point of view, the evaluation unit 13 determines, for example, in the tomographic image, from the high luminance region P2a that is expressed due to the surface reflection wave, in the depth direction, a layer number less than or equal to the number of layers calculated by the above formula (1). An image is extracted as an analysis target. The number of layers of the layered image that the evaluation unit 13 makes an analysis object is, for example, 3 or more and less than 200.

In addition, the thickness of the contact medium (B) is determined by the first surface (Ca) of the metal support (C) and the second The number of multiple reflections occurring between the surfaces Cb is set to be 5 or more and less than 200.

Next, the evaluation method of the internal state of the metal support body C by the evaluation part 13 is demonstrated.

The evaluation part 13 concerning this embodiment is comprised so that the uniformity of the internal structure of the metal support body C can be evaluated from the layered image in a tomographic image. Here, the uniformity of the internal structure of the metal support (C) evaluated by the evaluation unit 13 is not only the absence of voids and foreign matter inside the metal support (C), but also the crystal structure of the metal support (C) ( For example, chemical composition and grain size) uniformity is also included. This is because, as described above, when voids or foreign matter exist inside the metal support body (C), new defects are generated on the surface of the metal support body (C) when the metal support body (C) is being repaired. Further, the remaining life of the metal support (C) can be evaluated by evaluating the uniformity of the crystal structure (for example, chemical composition and crystal grain size) of the metal support (C).

As a result of intensive examination, the inventors of the present application have found that the change in the crystal structure inside the metal support (C) is a direct ultrasonic echo from the inside of the metal support (C), unlike the voids present inside the metal support (C). Although it is difficult to detect it as a change in attenuation degree when the ultrasonic wave is reflected multiple times on the inside of the metal support body (C), it has been found that it can be detected as a change in attenuation degree. In short, when there is a region where the crystal structure has changed inside the metal support (C), since the acoustic impedance is different from that of the surrounding region, scattering or reflection of ultrasonic waves occurs between the changed region and the surrounding region. It happens. As a result, when there is a region where the crystal structure has changed inside the metal support (C), the ultrasonic waves that are multiplely reflected into the inside of the metal support (C) are greatly attenuated during the multiple reflection process.

Also, conventionally, as an ultrasonic flaw detector for inspecting the internal state of metal, as in Patent Document 3, it is also known to use the mode of multiple reflection of ultrasonic waves. However, ultrasonic flaw detectors related to the prior art only inspect the presence or absence of cracks and voids, and cannot evaluate the uniformity of the internal structure of the metal support. Therefore, the remaining life of the metal support C cannot be appropriately judged by the ultrasonic flaw detector related to the prior art.

Fig. 8 is a diagram showing a change in the luminance value of the layered image P1 in the depth direction. 8 shows the changing mode of the luminance value in the depth direction at the same position (T1-T1') of the layered image P1 of each of FIGS. 4 and 5 .

FIG. 9 is a diagram showing a change in the luminance value in the transverse direction of the layered image P1 (ie, in the in-plane direction of the metal support C). 9 is a change in the luminance value in the transverse direction (ie, the in-plane direction of the metal support C) at the same position (T2-T2') of the layered image P1 in each of FIGS. 4 and 5 represents

8 and 9, the solid line graph shows the change in luminance value in the depth direction of the layered image P1 in FIG. , and the dotted line graph shows the changing mode of the luminance value in the depth direction of the layered image P1 in FIG. 5 (that is, the state in which the uniformity of the internal structure of the metal support body C is low).

As can be seen by referring to FIG. 8 , the attenuation of the luminance value in the depth direction of the layered image P1 in FIG. 5 is greater than that of the layered image P1 in FIG. 4 . Further, as can be seen by referring to FIG. 9 , the unevenness of the luminance values in the horizontal direction of the layered image P1 in FIG. 5 is larger than that of the layered image P1 in FIG. 4 .

This is because the internal structure of the metal support body (C) became non-uniform with deterioration of the metal support body (C). If the internal structure of the metal support (C) becomes non-uniform, as described above, the ultrasonic waves are scattered or reflected inside the metal support (C), and the degree of attenuation in the course of the ultrasonic waves traveling inside the metal support (C) gets bigger In other words, by analyzing the attenuation of the luminance value in the depth direction of the layered image P1 and the degree of deviation of the luminance value in the lateral direction of the layered image P1, the internal state of the metal support C can be evaluated. do.

The evaluation unit 13 evaluates the uniformity of the internal structure of the metal support body C in the thickness direction based on the change in the luminance value in the depth direction of the layered image P1 to be analyzed determined as described above. .

Specifically, the evaluation unit 13 determines the peak value of the luminance value of the first layer P1a on the upper layer side in the layered image P1 (for example, the uppermost layer in the layered image P1) and the second layer on the lower layer side. The degree of attenuation of the luminance values when comparing the peak values of the luminance values of the second layer P1b (eg, the lowermost layer in the layered image P1) (eg, the luminance value of the first layer P1a - the second layer) Based on the luminance value of the second layer (P1b)), the uniformity of the thickness direction of the internal structure of the metal support (C) is evaluated. For example, in the layered image P1 of FIG. 4, the degree of attenuation L1 of the luminance value between the first layer P1a and the second layer P1b is 100, whereas in the layered image P1 of FIG. 5 , the degree of attenuation (L2) of the luminance value between the first layer (P1a) and the second layer (P1b) is 180. The evaluation unit 13 compares the degree of change in the degree of attenuation detected in this way with a predefined reference value, thereby determining whether or not the metal support body C has deteriorated in that portion.

And the evaluation part 13 evaluates the uniformity of the thickness direction of the internal structure of the metal support body C in each scanning position of a tomographic image, for example. Thereby, at each position of the metal support body (C), the uniformity of the thickness direction of the internal structure of the metal support body (C) is evaluated.

In addition, here, although the peak value of the luminance value of the first layer P1a on the upper layer side in the layered image P1 is compared with the peak value of the luminance value of the second layer P1b on the lower layer side, the peak It is good also as an aspect which compares the luminance value of a part other than a value.

In addition, the evaluation unit 13 determines the uniformity of the internal structure of the metal support body C in the in-plane direction based on the change in the luminance value in the horizontal direction of the layered image P1 to be analyzed, determined as described above. Evaluate.

Specifically, the evaluation unit 13 determines the third layer P1c in the layered image P1 (for example, the uppermost layer in the layered image P1) at each position in the horizontal direction of the layered image P1. ) is obtained, and the degree of deviation (for example, standard deviation) is calculated. Then, the evaluation unit 13 evaluates the uniformity of the internal structure of the metal support body C in the in-plane direction based on the degree of variation. The evaluation unit 13 compares the degree of change in the standard deviation of the luminance value of the third layer P1c with a predefined reference value, for example, to determine whether the metal support C has deteriorated in that portion. decide whether

In addition, when evaluating the uniformity of the internal structure of the metal support body C in the in-plane direction, the evaluation unit 13 may refer only to the change in the luminance value of one layer of the layered image P1 in the transverse direction, and You may refer to the change manner of the luminance value in the horizontal direction in each of the plurality of layers of the image P1.

In addition, the evaluation unit 13 calculates the standard deviation of the luminance values in the thickness direction at any two or more points in the horizontal direction of the layered image P1, and uses the standard deviation to determine the metal support ( The uniformity of the in-plane direction of the internal structure of C) may be evaluated. In this case, the uniformity of the internal structure of the metal support body (C) in the in-plane direction is evaluated by, for example, calculating the difference between the standard deviations at adjacent points and calculating the standard deviation or average of the calculated differences. You can do it.

Further, when referring to the luminance values in the horizontal direction of one layer of the layered image P1, the evaluation unit 13 may also refer to the luminance values in the horizontal direction of portions other than the peak value of the luminance values within the layer concerned. . In addition, the evaluation unit 13 may refer only to the luminance value of only a part of the horizontal direction of the layered image P1 according to the area to be evaluated for the uniformity of the in-plane direction of the internal structure of the metal support body C.

In addition, when evaluation of the same metal support body (C) is performed regularly, the evaluation unit 13 preferably shows the change over time of the evaluation value of the internal structure of the metal support body (C). This makes it possible for the user to grasp the remaining life of the metal support body C more simply.

[Operation of ultrasonic inspection device]

Next, an example of the operation of the ultrasonic inspection device A will be described.

10 is a flow chart showing an example of the operation of the ultrasonic inspection device (A). In addition, the flow chart shown in FIG. 10 is a process which the ultrasonic inspection apparatus A sequentially executes according to the computer program, for example.

In step S1, the ultrasonic inspection device A uses the ultrasonic probe 2 to ultrasonically scan the inside of the metal support C, and captures an image of the inside of the metal support C. Thereby, a tomographic image of the inside of the metal support body (C) is created.

In step S2, the ultrasonic inspection device A extracts a layered image from within the tomographic image. In addition, at this time, the ultrasonic inspection device A detects, for example, the high luminance region of the first surface reflection wave from within the tomographic image, and calculates from the high luminance region in the depth direction by the above formula (1). A layered image of the number of layers is extracted.

In step S3, the ultrasonic inspection device A calculates an evaluation value of the internal structure of the metal support C in the thickness direction based on the change in the luminance value in the depth direction of the extracted layered image. In addition, at this time, the ultrasonic inspection apparatus A calculates the evaluation value of the thickness direction of the internal structure of the metal support body C in each scanning position of the tomographic image, for example.

In step S4, the ultrasonic inspection apparatus A calculates the evaluation value of the internal structure of the metal support C in the in-plane direction based on the change in the luminance value in the transverse direction of the extracted layered image. In addition, at this time, the ultrasonic inspection device A calculates, for example, an evaluation value of the internal structure of the metal support C in the horizontal direction at each depth position of the tomographic image.

[effect]

As described above, according to the ultrasonic inspection device A according to the present embodiment, it is possible to evaluate the state inside the metal support body C in a short time by a simple method. In particular, the ultrasonic inspection device (A) according to the present embodiment is based on multiple reflected waves between the first surface (Ca) and the second surface (Cb) of the metal support (C), resulting in a layered image expressed in a tomographic image. Based on this, since the internal state of the metal support (C) is evaluated, not only can voids or foreign substances present inside the metal support (C) be detected, but also the internal structure of the metal support (C) (eg For example, it is useful in that it can evaluate the uniformity of a crystal structure).

Thereby, it becomes possible to grasp|ascertain the state of the inside of the metal support body C more accurately, and, for example, the life of the metal support body C can be judged suitably.

(Other embodiments)

The present invention is not limited to the above embodiment, and various modifications are conceivable.

For example, in the said embodiment, a belt was shown as an example of the support body (metal support body (C)) which is the object of inspection by the ultrasonic inspection apparatus (A). However, a drum or a roll may be used as the support object to be inspected by the ultrasonic inspection apparatus A, in addition to the belt.

In addition, the support object to be inspected by the ultrasonic inspection device A is not limited to one entirely composed of a metal material, such as a metal plate, and the surface of the support composed of an insulating material is coated with a metal member by plating or the like. It may be formed and constituted. In addition, in that case, the metal member of a support body becomes the object of inspection by the ultrasonic inspection apparatus (A).

In the above embodiment, as an example of the evaluation unit 13, an aspect of directly extracting the layered image P1 to be analyzed from the ultrasonic image generated by the tomographic image generating unit 12 was shown. However, the evaluation unit 13 may use an image obtained by performing filter processing such as a smoothing filter or a feature extraction filter on the ultrasonic image generated by the tomographic image generation unit 12 as an analysis target.

Moreover, in the said embodiment, as an example of the evaluation part 13, although the aspect which shows only whether the metal support body C is good or bad was shown, the aspect of the evaluation output of the evaluation part 13 is arbitrary. The aspect of the evaluation output of the evaluation unit 13 may indicate the internal state of the metal support body C by a level, or for each index (for example, the uniformity of the internal structure of the metal support body C in the thickness direction) , the uniformity of the internal structure of the metal support body (C) in the in-plane direction, and the distribution state of voids inside the metal support body (C), etc.) may be evaluation values. In addition, it may indicate the remaining life of the metal support body (C).

As mentioned above, although the specific example of this invention was demonstrated in detail, these are only examples and do not limit the claim. The technology described in the claims includes various modifications and changes of the specific examples exemplified above.

The content of the disclosure of the specification, drawings, and abstract included in the Japanese application of Japanese Patent Application No. 2020-148156 filed on September 3, 2020 is incorporated herein by reference.

According to the ultrasonic inspection device for a metal support body according to the present disclosure, it is possible to evaluate the state inside the metal support body with high accuracy.

A: Ultrasonic Inspection Device
1: body of ultrasonic inspection device
11: transceiver
12: tomographic image generating unit
13: evaluation unit
14: notification unit
2: ultrasonic probe
21: piezoelectric vibrator
B: contact medium
B1: Eco Gel Pad
B2: gel
C: metal support
Ca: the first side of the metal support
Cb: the second side of the metal support

Claims (10)

An ultrasonic inspection device for inspecting a support at least partially formed of a metal member used to manufacture a film, comprising:
a transmission/reception unit that transmits ultrasonic waves into the support body through a contact medium using an ultrasonic probe and receives an ultrasonic echo from the inside of the support body;
a tomographic image generating unit that generates a tomographic image of the support based on the ultrasonic echo detected at each scanning position when the inside of the support is scanned by ultrasonic probe with the ultrasonic probe;
The tomographic image is image analyzed, and based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between the front and back surfaces of the metal part of the support of the ultrasonic wave transmitted from the ultrasonic probe, the support Evaluation unit that evaluates internal conditions
Ultrasonic inspection device having a. According to claim 1,
The evaluation unit, in the tomographic image, so that the signal component of the surface reflected wave from the surface of the support on the side facing the transmitting and receiving surface of the ultrasonic probe does not overlap with the signal component of the ultrasonic echo from within the support, Extracting the layered image below the number of layers calculated by the following formula (1) as an analysis target,
Ultrasonic inspection device.

(However, d1: the thickness of the support, d2: the thickness of the contact medium, v1: the speed of sound in the support, v2: the speed of sound in the contact medium) According to claim 1 or 2,
The evaluation unit evaluates the uniformity of the internal structure of the support in the thickness direction based on the change in the luminance value in the depth direction of the layered image.
Ultrasonic inspection device. According to claim 3,
The evaluation unit determines the uniformity of the internal structure of the support in the thickness direction based on the attenuation rate of the luminance value when comparing the first layer image on the upper layer and the second layer image on the lower layer in the layered image. to evaluate,
Ultrasonic inspection device. According to any one of claims 1 to 4,
The evaluation unit evaluates the uniformity of the internal structure of the support in the in-plane direction based on the change in the luminance value in the transverse direction of the layered image,
Ultrasonic inspection device. According to claim 5,
The evaluation unit evaluates the uniformity of the internal structure of the support in the in-plane direction based on the degree of deviation of the luminance value in the transverse direction of the layered image,
Ultrasonic inspection device. According to any one of claims 1 to 6,
The support is a belt, drum, or roll,
Ultrasonic inspection device. According to any one of claims 1 to 7,
The support is a support used in the film manufacturing process by the solution film forming method,
Ultrasonic inspection device. As an inspection method for inspecting a support used to manufacture a film,
processing using an ultrasonic probe to transmit ultrasonic waves into the support body through a contact medium and receive ultrasonic echoes from inside the support body;
a process of generating a tomographic image of the support based on the ultrasonic echo detected at each scanning position when ultrasonic scanning of the inside of the support with the ultrasonic probe;
The tomographic image is image analyzed, and based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between the front and back surfaces of the metal part of the support of the ultrasonic wave transmitted from the ultrasonic probe, the support A process that evaluates the state of the internal
A test method with As an inspection program for inspecting a support used to manufacture a film,
processing using an ultrasonic probe to transmit ultrasonic waves into the support body through a contact medium and receive ultrasonic echoes from inside the support body;
a process of generating a tomographic image of the support based on the ultrasonic echo detected at each scanning position when ultrasonic scanning of the inside of the support with the ultrasonic probe;
The tomographic image is image analyzed, and based on the aspect of the layered image expressed in the tomographic image due to multiple reflections between the front and back surfaces of the metal part of the support of the ultrasonic wave transmitted from the ultrasonic probe, the support A process that evaluates the state of the internal
Inspection program having.

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