TW201706594A - Defect inspection method and defect inspection device aiming to inspect a defect of the workpiece having a linear pattern or ridge formed on its surface - Google Patents

Abstract

A defect inspection method and a defect inspection device are disclosed, which aim to inspect a defect of a linear pattern, or ridge (92), formed on a surface of a workpiece (9). The method includes the following steps: a photographing step for sequentially photographing the inspection images (P) along the ridge (92); and an inspecting step for sequentially performing a defect inspection on the inspection images (P). For the inspecting step, a contour at the front face of the ridge (92) contained in the inspection images (P) is used for defect determination based on its continuity and the image area. For photographing step, the camera (3) is moved according to the shape information of the ridge (92) obtained from a process program on the workpiece (9).

Description

Defect inspection method and defect inspection device

The present invention relates to a defect inspection method and a defect inspection apparatus for inspecting defects of a workpiece having a linear pattern formed on a surface thereof.

Conventionally, a workpiece having a linear pattern on its surface has been known.

For example, in the die-cutting die for the sticker to be used, a ridge having a closed loop shape is formed on the surface of the die body, and the tip end of the ridge is used as a blade edge (refer to Japanese Laid-Open Patent Publication No. 2014-193966). .

In the manufacture of the punching die, the flat surface of the die body is subjected to cutting or etching, thereby forming a ridge of a predetermined pattern corresponding to the punched contour of the sticker or the like. Further, a punching blade is obtained by subjecting the tip end of the formed ridge to a quenching treatment or the like.

In the punching blade, in order to perform the punching processing correctly, in particular, a half cut which requires precision in cutting depth is required, and the width and height of the blade are required to be constant throughout the pattern.

This type of blade inspection can utilize a pattern inspection device for image processing.

As a pattern inspection device, it is a table for photographing a workpiece, that is, a punching die. In the surface, the shape of the blade of the line pattern is compared with the reference pattern. If there is a difference, it is judged to be defective (Ref. 2: JP-A-8-184570, Document 3: JP-A-Japan) Bulletin No. 2006-184037).

When checking the shape of the blade, it is not only to check the contour shape of the two sides of the blade edge, but also to check the width of the blade edge, that is, the distance between the two sides.

In the above-described pattern inspection apparatus, only the area including the linear pattern of the surface of the workpiece is selected to define the inspection range, thereby suppressing the processing time and the amount of data of the image to be inspected.

For example, in the inspection apparatus of Document 2, the inspection surrounding area is drawn by the operation means such as a mouse, and the inspection range is specified on the screen. Further, in the inspection apparatus of Document 3, a pattern which is a square surrounding the inspection target is selected, and the inspection is performed by arranging the frame on the screen.

However, regardless of the device, the designation of the inspection range is performed by the operator, which causes a burden on the operator and hinders automation.

Further, in the above-described pattern inspection device, since the workpiece image and the reference image are compared in each search segment, it is necessary to prepare the reference image in advance.

In particular, when the linear pattern formed on the surface of the workpiece is a fine shape, it is necessary to perform high-resolution recognition, and there is a problem that the amount of data of the reference image is large.

Therefore, in the defect inspection of the workpiece having a linear pattern such as the blade edge of the aforementioned punching die, if an existing pattern inspection device is used, the aforementioned The problem of the operation of the inspection range and the problem of preparing the reference image are inevitable, and it is difficult to perform an efficient defect inspection.

Further, the same problem is not limited to the continuous linear pattern of the ridges as in the above-mentioned die-cutting mold, and the grooves have a continuous linear pattern and a linear pattern in which the optical characteristics are different on the surface of the workpiece. It will happen again.

An object of the present invention is to provide a defect inspection method and a defect inspection device which can efficiently perform defect inspection of a workpiece having a linear pattern on its surface.

The defect inspection method of the present invention is a defect inspection method for inspecting a defect of the linear pattern on a workpiece having a linear pattern formed on a surface thereof, characterized in that the inspection image is sequentially photographed along the linear pattern. The photographing step and the step of inspecting the defect inspection sequentially on the inspection image, wherein the inspection step determines the defect based on at least one of continuity and image area of the linear pattern included in the inspection image.

According to the present invention, since the defect is determined based on at least one of the continuity of the line pattern included in the inspection image and the image area, it is not necessary to prepare the reference image in advance. In addition, the inspection images are sequentially photographed along the line pattern, so that it is not necessary to perform the operation of designating the inspection section.

Therefore, according to the present invention, it is possible to efficiently form the surface Defect inspection of workpieces in a linear pattern.

In the defect inspection method of the present invention, in the inspection step, the inspection image is divided into a pattern region indicating the linear pattern and an outer region of the pattern region, and the pattern is calculated according to a difference in optical characteristics. The area and the area outside the pattern are compared with other inspection images, and it is determined that there is no defect as long as the area does not change.

In the present invention, as the area of the pattern area and the area outside the pattern, the area of each of the inspection images and the number of pixels can be used, and the occupancy ratio of either one can be used. Further, as another inspection image to be compared, for example, an adjacent previous inspection image can be used.

According to the present invention, the defect determination of the inspection step can be performed by a simple operation of calculating the area of the pattern area and the area outside the pattern in the inspection image. For example, as long as it is a continuous line pattern having a constant width, the area of the pattern area and the area outside the pattern in the inspection image photographed along the line pattern are constant regardless of the area.

Therefore, as in the present invention, the area of the pattern area and the area outside the pattern is calculated for each of the plurality of inspection images photographed along the line pattern, and the comparison is performed in order, whereby the defect determination in the inspection step can be efficiently performed.

In the defect inspection method of the present invention, in the inspection step, the inspection image is divided into: a pattern region indicating the linear pattern and a pattern outer region outside the pattern region, according to the difference in optical characteristics, in the pattern a boundary line between the region and the outer region of the pattern as the aforementioned line The contour of the pattern is detected, and as long as the aforementioned contour is continuous, it is determined that there is no defect.

In the present invention, whether or not the contour is continuous is determined, and in one inspection image, the displacement or inclination angle of the arbitrary portion of the contour and the portion adjacent thereto in the width direction can be detected. In addition, the same continuity can be determined by comparing with the contours of other adjacent inspection images.

The fact that the contour is continuous means that there is no expected discontinuity corresponding to the defect in the contour. The discontinuity corresponding to the defect includes a case where the contour has a significant curved portion or a bent portion, and a portion that is sharply larger than the curvature of the surrounding portion, and a corner portion such as a contour line intersects before and after the arbitrary point. The situation, etc. Even if it is the corner of the linear pattern, when the buckling is constituted by a curve, it is possible to determine that the contour is continuous. Further, in the present invention, the linear pattern is not limited to being constituted by a straight line portion, and a part or even a whole may be constituted by a curved line.

In the present invention, the degree of discontinuity can be appropriately set in accordance with the degree of the defect to be inspected.

According to the present invention, the defect determination of the inspection step can be performed by detecting the outline of the linear pattern of the inspection image and determining the continuity thereof. For example, as long as the continuous line pattern has a notch, the outline of the portion becomes discontinuous, and can be easily determined by comparison with the adjacent portion.

In the defect inspection method of the present invention, it is preferable that the inspection image is specified by an inspection frame having a predetermined shape, and after the first inspection frame is placed in an arbitrary portion of the linear pattern in the photographing step, The portion adjacent to the pattern is arranged in sequence with the next inspection frame, whereby a plurality of the inspection images along the linear pattern are imaged.

According to the present invention, a plurality of inspection images along the line pattern can be imaged for the entire or any section of the line pattern, and the defect is determined based on at least one of the continuity of the line pattern and the image area in the inspection step. , you can get a suitable inspection image.

In the defect inspection method of the present invention, it is preferable that the workpiece is a linear pattern formed on a surface by a processing device that operates in accordance with a processing program, and the image capturing step is based on the line pattern included in the processing program. The shape data allows the parts of the aforementioned inspection image to be moved in sequence.

According to the present invention, the movement path during the operation of sequentially inspecting the image can be set with reference to the machining program for machining the workpiece. Therefore, in order to set the movement path, it is not necessary to additionally photograph the workpiece, and it is not necessary to indicate by manual operation.

In the defect inspection method of the present invention, it is preferable that a camera is mounted on the processing device that processes the workpiece, and the inspection image is captured by the camera.

According to the present invention, after the workpiece is processed in a line pattern, the defect inspection of the line pattern can be performed immediately. Therefore, in order to perform inspection after processing, it is not necessary to perform an operation of transferring a workpiece or the like. Moreover, the processing device can also be used for defect inspection, which can reduce equipment cost and equipment space.

Preferably, in the defect inspection method of the present invention, the linear pattern is moved while the camera is moved along the linear pattern in the photographing step. The flash is intermittently illuminated, and the aforementioned inspection image is photographed by the aforementioned camera while being illuminated by the flash.

According to the present invention, it is not necessary to stop the camera moving along the line pattern, and a clear inspection image can be obtained by flash photography. Therefore, it is possible to perform photographing in a short time compared to the case where photographing is performed by moving or stopping repeatedly. Moreover, high-speed photography can be performed without using a special camera such as a high-speed camera, so that the equipment cost can be reduced.

The defect inspection device of the present invention is a defect inspection device for inspecting a defect of the linear pattern on a workpiece having a linear pattern on a surface thereof, characterized in that the inspection image is sequentially photographed along the linear pattern The photographing unit and the inspection unit that sequentially performs the defect inspection on the inspection image, wherein the inspection unit determines the defect based on at least one of continuity and image area of the linear pattern included in the inspection image.

In the present invention, as the photographing unit, for example, a camera mounted on a work machine for processing a workpiece can be used as the inspection unit, and a control device for controlling the work machine can be used. As the control device, an NC device (numerical control device) connected to the work machine, a computer system connected to the outside of the NC device, or the like can be used.

According to the defect inspection device of the present invention, the same operational effects as those of the defect inspection method of the present invention described above can be obtained.

According to the present invention, it is not necessary to prepare a reference image in advance, and it is not necessary to perform an operation of designating an inspection section when performing photography of an inspection image. Therefore, according to the present invention, the defect inspection of the workpiece in which the linear pattern is formed on the surface can be efficiently performed.

1‧‧‧ Defect inspection device

2‧‧‧Working machinery

3‧‧‧ camera

3A‧‧‧Flash

4‧‧‧ Tools

5‧‧‧Control device

6‧‧‧ computer system

9‧‧‧Workpiece

21‧‧‧ Machine tools

22‧‧‧

23‧‧‧ machine column

24‧‧‧ beams

25‧‧‧ saddle

26‧‧‧ spindle head

27‧‧‧ Spindle

51‧‧‧Processing program

61‧‧‧Processing program

62‧‧‧Checking program

90‧‧‧Substrate

91‧‧‧Upper surface

92‧‧‧

93‧‧‧ front end

94, 95‧‧‧ side

AC1, AC2, AC3‧‧ ‧ bright area

AL1, AL2, AL3, AR1, AR2, AR3‧‧‧ Dark areas

EL1, EL2, EL3, ER1, ER2, ER3‧‧‧ boundary line

Lf‧‧‧ area

P, P1, P2, P3‧‧‧ Check images

Pf‧‧‧ check box

Fig. 1 is a schematic view showing the structure of a device according to an embodiment of the present invention.

Fig. 2 is a perspective view showing the workpiece of the above embodiment.

Fig. 3 is a partially cutaway perspective view showing the workpiece of the above embodiment.

Fig. 4 is a perspective view showing the photographing step of the above embodiment.

Fig. 5(A) is a plan view showing (A) of the photographing step of the above embodiment, and Fig. 5(B) is a cross-sectional view.

Fig. 6 is a plan view showing a normal state of the inspection step of the above embodiment.

Fig. 7 is a plan view showing defect detection in the inspection step of the above embodiment.

Fig. 8 is a plan view showing another defect detection in the inspection step of the above embodiment.

Fig. 9 is a perspective view showing another line pattern which can be inspected in the above embodiment.

Fig. 10 is a perspective view showing a photographing step of another embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described based on the drawings.

[Defect inspection device 1]

In FIG. 1, the defect inspection device 1 is constructed by attaching a camera 3 to a spindle head 26 of the work machine 2.

The work machine 2 performs three-dimensional machining of the workpiece 9 by means of a tool 4 mounted on the spindle 27.

The work machine 2 is provided with a stage 22 and a door type frame 23 on the upper surface of the machine tool 21. The cross member 24 of the frame 23 supports the spindle head 26 via the saddle 25, and the spindle head 27 is supported by the spindle head 26.

The stage 22 is movable in the X-axis direction with respect to the machine tool 21, and the saddle 25 is movable in the Y-axis direction along the beam 24, and the spindle head 26 is movable in the Z-axis direction with respect to the saddle 25.

By the above-described three-axis movement, the camera 3 and the tool 4 can be three-dimensionally moved with respect to the workpiece 9 placed on the stage 22.

In order to control the three-dimensional operation of the work machine 2, the work machine 2 is connected to the control device 5, and the control device 5 is connected to the computer system 6 for control.

The control device 5 is an existing numerical control device that controls the operation of the work machine 2 based on a control command from the computer system 6. The machining program 51 is stored in the control device 5, and the operation of the work machine 2 for machining the workpiece 9 is described in the machining program 51.

The processing program 51 is executed by the operation control device 5 or by instructing the control device 5 via the computer system 6, thereby controlling the operation of the work machine 2. As described above, in the work machine 2, the workpiece 9 can be processed by the tool 4, and the workpiece 9 can be formed into a predetermined shape.

The computer system 6 stores an inspection program 62 for causing the work machine 2 to perform the operation of the defect inspection method according to the present invention.

Further, in order to refer to the inspection program 62, the computer system 6 stores the same processing program 61 as the processing program 51 stored in the control device 5.

In the defect inspection device 1 of the present embodiment, the camera 3 installed in the work machine 2 is an imaging unit, and the computer system 6 that operates in accordance with the inspection program 62 is an inspection unit.

[Workpiece 9]

In Fig. 2, the workpiece 9 of the present embodiment is a punching die for use as a sticker, and a ridge 92 as a punching blade is formed on the flat upper surface 91.

The ridge 92 is a linear pattern having a continuous annular shape, and is formed by cutting the surface of the base material 90 of the workpiece 9 by a tool 4 such as an end mill.

As shown in FIG. 3, the front end surface 93 of the ridge 92 is flat, and the front end surface 93 is processed to have the same height throughout the entire length of the ridge 92.

The ridge 92 is used as a punching blade, and is formed in a mountain shape having a triangular cross section and a side surface 94 on both sides of the ridge 92 so that the width of the front end surface 93 is small and the width of the root portion, that is, the side of the base material 90 is increased. 95 becomes an inclined surface, respectively.

[Defect inspection order]

In the present embodiment, the tool 4 is assembled in the working machine 2 In the state, the machining program 51 is executed by the control device 5, and the workpiece 9 having the aforementioned ridge 92 (linear pattern) is formed.

Further, after the processing, the inspection program 62 is executed by the computer system 6 using the camera 3 mounted on the work machine 2, and the linear pattern, that is, the shape of the end surface 93 before the action of the punching blade in the ridge 92 is performed. Defect inspection.

The defect inspection according to the inspection program 62 is performed by the photographing step and the inspection step described below.

[Photography step]

In the photographing step, the ridges 92 of the workpiece 9 are photographed by the camera 3 mounted on the work machine 2.

In Fig. 4, the photographing of the camera 3 is performed on a region surrounded by the inspection frame Pf on the surface of the workpiece 9. Further, the image captured by the camera 3 is transmitted from the control device 5 to the computer system 6, and sequentially stored as the inspection image P.

The resolution of the inspection image P is set so as to check a sufficiently high resolution required for the front end surface 93 of the fine protrusion 92 with respect to the entire workpiece 9. Therefore, the size of the image P is checked, and it cannot be expanded until the entire ridges 92 can be photographed together.

Then, the computer system 6 for executing the inspection program 62 operates the work machine 2, moves the camera 3 along the ridges 92, and sequentially moves the inspection frame Pf of the camera 3 to perform photography.

In this way, a plurality of inspection images P taken along the ridge 92 are taken. The order is continuous, whereby the entire ridge 92 can be photographed.

In the photographing step, in order to move the camera 3 along the ridge 92, the computer system 6 for executing the inspection program 62 refers to the processing program 61 stored in the computer system 6, and obtains the ridge according to the contents of the processing instruction. Information on the location and shape of 92. Further, the movement path of the camera 3 is set in accordance with the shape data of the obtained ridges 92 so as to track the ridges 92.

Specifically, the first inspection frame Pf is placed in an arbitrary portion of the ridge 92, and after the inspection frame Pf is photographed to obtain the inspection image P, the amount corresponding to one inspection frame Pf is moved along the ridge 92, and The next inspection frame Pf is placed in a portion adjacent to the inspection frame Pf where the photographing is completed, and the inspection image P is photographed. Hereinafter, the tracking ridges 92 are sequentially moved and photographed in order, and a plurality of inspection images P covering the entire ridges 92 are obtained.

As shown in FIG. 5, the inspection frame Pf and the region of the inspection image P sequentially photographed are rectangular shapes extending in the width direction of the ridges 92.

As shown in FIGS. 5(A) and (B), the inspection frame Pf is set so as to reach the upper surface 91 of the workpiece 9 beyond the front side faces 93 of the ridges 92, beyond the inclined side faces 94, 95.

Further, the plurality of inspection images P are arranged along the ridges 92 in a state in which the respective long sides are adjacent to each other. The movement of the inspection frame Pf is performed by arranging a plurality of inspection images P in such a manner.

[checking step]

The inspection step is started before the entire photographing step is completed for all the ridges 92. In other words, the defect inspection is performed on the inspection image P that has already been photographed while performing the photographing step at another portion.

In the inspection step, the area inspection relating to the area of the inspection image P and the continuity inspection relating to the continuity of the contour of the inspection image P are performed in total.

In the inspection step, the inspection image P is divided into a pattern area indicating a line pattern and a pattern area outside the pattern area in accordance with the difference in optical characteristics.

In FIG. 6, the adjacent inspection images P1, P2, and P3 are divided into: bright areas AC1, AC2, AC3 extending longitudinally in the center in the width direction, and dark areas AL1, AL2, AL3 on both sides thereof. Dark areas AR1, AR2, AR3.

The bright areas AC1, AC2, and AC3 are areas (pattern areas) in which the line pattern, that is, the front end surface 93 of the ridge 92 is imaged. Since the front end surface 93 is flat and faces the camera 3, most of the illumination light is reflected and incident on the camera 3, so that the inspection images P1, P2, and P3 become bright regions.

The dark areas AL1, AL2, AL3 and the dark areas AR1, AR2, AR3 are areas (out-of-pattern areas) where a line pattern, that is, the side faces 94, 95 of the ridges 92 are captured. The side faces 94, 95 are faces that are inclined with respect to the camera 3, and the reflected light of the illumination light incident on the camera 3 is reduced. Therefore, the inspection images P1, P2, and P3 become dark regions.

[area inspection]

In the area inspection, the number of pixels in the bright areas AC1 to AC3 and the dark areas AL1 to AR3 is integrated in each of the inspection images P1 to P3, and the defect is determined based on the change.

Specifically, it is assumed that in the inspection image P1, the bright area AC1 is 20 pixels, the dark area AL1 is 40 pixels, and the dark area AR1 is 40 pixels.

In FIG. 6, in the next inspection image P2 and the next inspection image P3, the bright areas AC2 and AC3 are 20 pixels, the dark areas AL2 and AL3 are 40 pixels, and the dark areas AR2 and AR3 are 40 pixels, respectively.

That is, in the inspection images P1 to P3, the number of pixels in the bright areas AC1 to AC3 and the dark areas AL1 to AR3 does not change.

Therefore, it can be determined that there is no defect in the front end surface 93 of the ridge 92 at the portion where the images P1 to P3 are inspected.

In FIG. 7, the inspection images P1 and P2 are the same as those in FIG. 6, but in the inspection image P3, the dark area AL3 on the left side protrudes and invades a part of the bright area AC3.

In this state, the dark area AL3 exceeds 40 pixels, and the bright area AC3 is lower than 20 pixels. In other words, the areas of the bright region (pattern region) and the dark region (out-of-pattern region) in the inspection image P3 are changed with respect to the inspection images P1 and P2, and it is determined that there is a defect.

Like this defect of Fig. 7, when a notch is formed at the edge of the front end face 93, it is detected.

Further, when the current end surface 93 is deformed in the width direction like the inspection image P3 shown in FIG. 8, the number of pixels in the bright area AC3 does not change with respect to the other inspection images P1 and P2, but the dark areas on both sides The number of pixels in AL3 and AR3 changes, and defects can be detected.

[Continuity check]

In FIG. 8, as described above, when the current end surface 93 is deformed in the width direction as in the inspection image P3, the continuity of the outline of the bright region (pattern region), that is, the dark region (out-of-pattern region) is checked. The continuity of the shape of the boundary line can determine the defect.

In the continuity check, in each of the inspection images P1 to P3, the boundary line EL1 to EL3 of the bright area AC1 to AC3 and the dark area AL1 to AL3 and the boundary line ER1 of the bright area AC1 to AC3 and the dark area AR1 to AR3 are ER1~ The ER3 is detected as a line pattern, that is, the contour of the front end face 93 of the ridge 92.

The boundary lines EL1 to EL3 and the boundary lines ER1 to ER3 can be detected based on the brightness difference between the bright areas AC1 to AC3 and the dark areas AL1 to AL3, and the brightness difference between the bright areas AC1 to AC3 and the dark areas AR1 to AR3. Measure its position.

Here, in the inspection images P1, P2, the boundary lines EL1, EL2 extend linearly. However, in the inspection image P3, the dark area AL3 invades the bright area AC3, and the boundary line EL3 is curved in an arc shape. As a result, with respect to the extension line of the boundary line EL1, EL2 (indicated by the chain line in the inspection image P3), the boundary line EL3 is largely shifted, and this is judged to be a defect.

Similarly, the boundary line ER3 is curved in an arc shape with respect to the boundary line ER1, ER2, and the extension line of the ER2, ER2 (indicated by the chain line in the inspection image P3), and the boundary line ER3 is largely offset, and It is judged to be a defect.

[End of inspection]

When the above-described photographing step and inspection step are performed in sequence, if no defects are found in the area inspection and the continuity inspection, and the linear pattern, that is, the entire projection 92 is inspected once, the workpiece 9 to be inspected is judged as "None." The defect is checked and the defect check is ended.

On the other hand, if a defect is found in any of the area inspection and the continuity inspection, the photographing step and the inspection step are sequentially executed at this point in time, and a defect is recorded in the workpiece 9.

[Effect of the embodiment]

In the present embodiment, in the inspection step, the defect can be determined based on at least one of the linear pattern of the inspection image P, that is, the continuity of the ridge 92 and the image area. Therefore, it is not necessary to prepare the ridge in advance during the defect inspection. The reference image of 92.

Further, in the photographing step, the inspection image P is sequentially photographed along the line pattern, that is, the ridges 92, so that the operator does not need to perform the operation of designating the inspection section.

Therefore, the defect inspection of the workpiece 9 in which the linear pattern, that is, the ridge 92 is formed on the surface can be efficiently performed.

In the present embodiment, since the area inspection is used in the inspection step, by calculating the area of the pattern area (light areas AC1 to AC3) and the pattern area (dark areas AL1 to AR3) in the inspection image P, it is as simple as the operation. The defect determination of the inspection step can be performed.

In particular, in the present embodiment, the number of pixels in each of the inspection images P1 to P3 is integrated and compared with the number of pixels of other inspection images, so that the defect determination in the inspection step can be performed more efficiently.

In the present embodiment, since the continuity inspection is also performed in the inspection step, the defect inspection can be performed more surely.

In the continuity check, the defect determination of the inspection step can be performed by detecting the outline of the line pattern of the inspection image P (detecting the boundary line between the bright area and the dark area) and determining the continuity thereof.

In the present embodiment, in the photographing step, the inspection frame Pf is sequentially arranged along the line pattern, that is, the ridges 92, and a plurality of inspection images P are imaged, so that the aforementioned area inspection suitable for the inspection step can be obtained. And inspection images for continuity inspection.

In particular, in the present embodiment, the movement path during the operation of sequentially inspecting the image P can be set with reference to the same machining program 61 as the machining program 51 for machining the workpiece 9. Therefore, in order to set the movement path, it is not necessary to additionally photograph the workpiece 9, and it is not necessary to indicate it by manual operation.

Further, in the present embodiment, the camera 3 is attached to the work machine 2 for processing the workpiece 9, and the inspection image P is sequentially photographed by the camera 3. Therefore, the workpiece 9 is linearly patterned, that is, the ridge 92 is formed. After processing, defect inspection can be performed immediately.

Therefore, after the processing, it is not necessary to perform an operation of transferring the workpiece 9 or the like for the purpose of inspection. Moreover, the work machine 2 can be used as the defect inspection device 1, which can reduce equipment cost and equipment space.

[Other Embodiments]

The present invention is not limited to the above-described embodiments, and modifications and the like within the scope of the object of the invention are also included in the invention.

In the above embodiment, both the area inspection and the continuity inspection are performed in the inspection step, but only one of them may be performed.

The area inspection is not limited to the above embodiment, that is, the pattern area (light areas AC1 to AC3) and the two pattern outer areas (the dark areas AL1 to AL3 and the dark areas AR1 to AR3) in the inspection image P are not limited. ) the area of each.

For example, two outer regions (the dark regions AL1 to AL3 and the dark regions AR1 to AR3) are combined, and two bright pattern regions and a dark outer region may be calculated.

In particular, in the case of processing in two areas, since the inspection image P is divided into two areas, it is necessary to calculate the area (the number of pixels) of either the bright pattern area and the dark pattern area, using the check box Pf. The area of the other area (the total number of pixels) of the known inspection image P is subtracted from the area of the one, and the other area can be calculated.

Like this area inspection, it is also possible to detect the defect of the contour of one side of the area AC3 as shown in Fig. 7.

The continuity check is not limited to the above-described embodiment, that is, it is not limited to the pattern areas (light areas AC1 to AC3) in the inspection image P and the pattern outer areas on both sides (the dark areas AL1 to AL3 and the dark areas). The boundary line of AR1~AR3), enter it with the adjacent inspection image P Line comparison.

For example, in the same inspection image P, the continuity of the boundary line presented therein is checked, and the detection is equivalent to the discontinuity of the defect.

In the above embodiment, the linear pattern to be inspected is a rectangular protrusion 92 as shown in Fig. 2 . The object to be inspected in the above-described embodiment is not limited to a rectangle each having a straight line, and a part of the whole may be a linear pattern composed of a curved line. For example, a circular protrusion as shown in FIG. 9 may be used. 92A.

In the above-described embodiment, in the photographing step, photographing is performed using the inspection frame Pf of a predetermined shape, and a plurality of inspection images P of a certain size are obtained.

On the other hand, in the case of photographing, the inspection frame Pf is not used, and an image having a shape and a size corresponding to the linear pattern such as the ridge 92 is obtained, and the inspection may be performed in the inspection step.

However, as in the present embodiment, a plurality of inspection images P are set to a constant shape size, and the inspection of the inspection step can be efficiently processed.

In the above-described embodiment, the imaging step is performed on a part of the line 92, that is, the portion of the protrusion 92, and the inspection step is performed on the portion of the inspection image P that has been photographed, and the photographing step and the inspection step are performed in parallel to obtain the processing time. Efficiency.

However, the linear pattern, that is, the ridges 92 are sequentially subjected to the photographing step, and after the inspection image P is obtained for all of the ridges 92, the inspection step may be performed together.

In the foregoing embodiment, during the photographing step, the camera 3 is placed along When the ridge 92 (linear pattern) is moved, a plurality of inspection images P are acquired while photographing is performed by the inspection frame Pf. In order to obtain a clear image, the general camera 3 must be stopped at the shooting position. That is to say, the camera 3 has to repeatedly perform the operations of moving to stop-photographing-moving, and there is a possibility that the processing time becomes redundant.

On the other hand, as another embodiment of the present invention, flash photography can be employed.

In Fig. 10, this embodiment basically has the same structure as the embodiment of Figs. 1 to 9 described above. However, the flash unit 3A is provided adjacent to the camera 3, and the strong light can be intermittently irradiated to the area Lf covering the inspection frame Pf of the camera 3.

In the present embodiment, the camera 3 is continuously moved along the ridges 92. During this period, the ridges 92 are intermittently illuminated by the flasher 3A, and the camera 3 is photographed during the illumination.

Thus, the ridge 92 is illuminated by the strong light of the flash 3A, and the image captured by the camera 3 is made clear. Furthermore, the processing time of the photographing can be shortened without stopping the camera 3. As a result, clear images can be obtained at high speed without using a high-speed camera, which can reduce equipment costs.

In the above-described embodiment, in the work machine 2 for processing the workpiece 9, the tool 4 is attached to the main shaft 27, and the camera 3 is attached to the spindle head 26, whereby the defect inspection device 1 is used.

However, instead of setting the camera 3 and the tool 4 at the same time as the work machine 2, a replacement type may be employed. For example, after the tool 27 is mounted on the spindle 27 to process the workpiece 9, the tool 4 is removed, instead of the spindle 27 It is also possible to mount the camera 3 to perform photographing of the workpiece 9.

When the camera 3 is mounted on the spindle 27 in this manner, the camera 3 is not required to be attached to the spindle head 26, and the camera 3 can be easily mounted using the automatic tool changing device.

However, frequent replacement of the tool 4 and the camera 3 becomes inefficient, and therefore it is limited to sequentially perform the following sequence: after the processing of the workpiece 9 by the tool 4 is completed, the ridge 92 is performed by the camera 3 (linear Photography) photography.

On the other hand, as in the above-described embodiment, as long as the camera 3 and the tool 4 are provided in the work machine 2, the following procedure can be employed: a part of the workpiece 9 is processed, the processed portion is photographed, and the next portion is processed. photography.

In the above-described embodiment, the work machine 2 is provided with the camera 3 and also serves as the defect inspection device 1. However, the work tool 2 for processing the workpiece 9 may be used independently, and the dedicated defect inspection device 1 may be used.

In this case, it is preferable that the machining program 51 executed by the control device 5 of the machine tool 2 or the shape of the ridge 92 (linear pattern) designated by the machine tool 2 is taken out and input into the dedicated defect inspection device 1 to be used for photography. step.

In the above embodiment, the same machining program 61 as the machining program 51 is also stored in the computer system 6. The machining program 51 is a program stored in the control device 5 for processing the workpiece 9, and is photographed by referring to the machining program 61. The step performs a linear pattern, that is, tracking of the ridges 92. However, if there are other shape information of the line pattern other than the processing programs 51, 61 for processing the workpiece 9, the data may be used.

3‧‧‧ camera

9‧‧‧Workpiece

90‧‧‧Substrate

91‧‧‧Upper surface

92‧‧‧

P‧‧‧Check images

Pf‧‧‧ check box

Claims (8)

A defect inspection method for detecting a defect of the linear pattern on a workpiece having a linear pattern on a surface thereof, characterized in that the method includes: photographing the inspection image sequentially along the linear pattern And a step of performing a defect inspection on the inspection image sequentially, wherein the inspection step determines the defect based on at least one of continuity of the linear pattern included in the inspection image and an image area. The defect inspection method according to claim 1, wherein in the inspection step, the inspection image is divided into: a pattern region indicating the linear pattern and an outer pattern of the pattern region, according to a difference in optical characteristics. In the outer region, the area of the pattern region and the outer region of the pattern is calculated, and compared with the other inspection images, it is determined that there is no defect as long as the area does not change. The defect inspection method according to claim 1, wherein in the inspection step, the inspection image is divided into: a pattern region indicating the linear pattern and a pattern outside the pattern region, according to a difference in optical characteristics. The outer region is detected by using a boundary line between the pattern region and the outer region of the pattern as a contour of the linear pattern. As long as the aforementioned contour is continuous, it is determined that there is no defect. The defect inspection method according to the first aspect of the invention, wherein the inspection image is specified by an inspection frame having a predetermined shape, and after the first inspection frame is placed in an arbitrary portion of the linear pattern in the photographing step The next inspection frame is sequentially disposed at a portion adjacent to the linear pattern, thereby capturing a plurality of the inspection images along the linear pattern. The defect inspection method according to claim 4, wherein the workpiece is a linear pattern formed on a surface by a processing device that operates according to a processing program, and the photographing step is based on the processing program The shape data of the aforementioned linear pattern is included to sequentially move the portion of the inspection image. The defect inspection method according to claim 5, wherein a camera is mounted on the processing device that processes the workpiece, and the inspection image is imaged by the camera. The defect inspection method according to any one of claims 1 to 6, wherein the linear pattern is intermittently illuminated by a flash while moving the camera along the linear pattern in the photographing step. The aforementioned inspection image is performed by the aforementioned camera during illumination by the aforementioned flash lamp photography. A defect inspection device for inspecting a defect of the linear pattern on a workpiece having a linear pattern on a surface thereof, characterized in that the defect inspection device sequentially photographs the inspection image along the linear pattern And an inspection unit that sequentially performs defect inspection on the inspection image, wherein the inspection unit determines the defect based on at least one of continuity of the linear pattern included in the inspection image and an image area.