JP2009258069A - Inspection apparatus and inspection method of foreign matters within hole of spinneret - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and method for simultaneously inspecting a plurality of discharge holes provided and opened in a spinneret, detecting foreign matters within a plurality of the discharge holes at once without detecting the presence of the residual foreign matters within the holes one by one, and surely inspecting the foreign matters within the holes in a short period of time without requiring a long time. <P>SOLUTION: In the inspection apparatus and the inspection method of foreign matters within the holes of the spinneret, a plurality of image data groups are obtained at a high resolution by using a scan camera and scanning the spinneret, and are combined. The presence of the foreign matters within the holes is detected at once from the created combined image data in a plurality of the respective discharge hole groups provided and opened in the spinneret by using image processing. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an apparatus and a method for automatically inspecting the presence of foreign matter in a polymer discharge hole drilled in a spinneret for spinning synthetic fibers.

  In general, a synthetic fiber is produced by spinning a spinning solution from a discharge hole formed in a spinneret. However, if the discharge hole drilled in the spinneret is dirty or if impurities adhere to the hole, good discharge of the spinning solution is hindered, causing not only single yarn breakage but also spinning itself. A failure that can not be done occurs. For this reason, abnormalities in the discharge holes, which are the lifeline of the spinning technology, are inspected, and if there are abnormalities, the inside of the discharge holes is cleaned for each hole using a drill or air.

  However, although the number of discharge holes to be drilled in the base depends on the shape, it is usually large from several tens to several thousand and the hole diameter is as small as 1 mm or less. However, it is necessary to inspect the dirt carefully with the naked eye. When dirt or foreign matter is found in the hole, the dirt or foreign matter is removed using a needle-like jig or air.

  Needless to say, such a base inspection requires enormous manpower and time for inspection and hole cleaning, and since it is a visual inspection, a long-time inspection is difficult because the eyes are tired. Therefore, there has been a tendency that the cleaning of the hole is neglected, and a human error occurs in the hole inspection and the hole cleaning.

  Thus, Patent Document 1 and the like have proposed an attempt to carry out the cap inspection with an automatic inspection device without relying on human hands. In this prior art, in order to detect foreign matter remaining in the hole after the base is once cleaned with a cleaning solution, light is irradiated from below the base for each hole, and the area value of the light passing through the discharge hole is obtained. It is intended to determine the presence or absence of foreign matter in the hole. That is, if the foreign matter remains in the hole, the light projected by the remaining foreign matter is blocked, and therefore, the principle of reducing the area value of transmitted light to be detected is used.

  However, as described above, the number of discharge hole groups drilled in the spinneret is very large, from several tens to several thousand, so even if an automatic inspection using a computer is performed, a large amount of inspection is required for each hole. Therefore, a technique capable of inspecting in a short time is required.

  It is also important to inspect the scratches on the polymer discharge surface of the spinneret in addition to the foreign matter in the hole. This is because even a scratch on the polymer discharge surface causes a factor to hinder the stability of the polymer discharged from the discharge hole. Such a flaw inspection can also be performed by visual judgment of an inspector who performs a cap inspection. However, if inspection of a flaw on the polymer discharge surface can be performed at the same time as inspection of foreign matter in a hole without requiring manual labor, it is advantageous because labor required for the inspection can be omitted.

JP-A-7-243831 JP 2006-267000 A

  In view of the above-described problems of the prior art, the object of the present invention is to simultaneously inspect a plurality of discharge holes formed in the spinneret and detect the presence or absence of foreign matters remaining in the holes. Provided is an apparatus and a method capable of detecting foreign matter in a hole at a time for a large number of discharge holes, and thereby inspecting the foreign matter in a hole in a short time and without much time. There is to do. It is another object of the present invention to provide an apparatus and a method capable of inspecting scratches on a polymer discharge surface of a spinneret simultaneously with the inspection of foreign matter in a hole.

Here, as means for solving the above-mentioned problems, “a spinneret having a large number of discharge holes, illumination provided on one side of the spinneret, and the other side of the spinneret” A scanning camera provided opposite to the illumination, and a magnifying lens attached to the scanning camera and magnifying the image of the inspection light projected from the illumination and passed through the ejection hole to a predetermined magnification, A positioning driving means for accurately positioning control to a position where the scan camera scans the image data and an image data group including at least a perforation region of a discharge hole formed by a spinneret by the scan camera, A device for detecting foreign matter in a spinneret comprising an image processing device for detecting foreign matter in a hole present in a number of ejection holes at a time,
The image processing device generates at least one composite image data for a plurality of ejection holes by combining the image data groups, and presets the gradation of light and darkness of the pixel groups included in the composite image data Perform binarization processing that distributes each value to `` bright '' or `` dark '' based on the gradation, and recognizes it as a discharge hole when the pixel group determined as `` bright '' is a continuous aggregate The pixel number of the aggregate of pixels determined to be “bright” for each of the recognized ejection holes is calculated as an area value, and the area value is a pixel set in advance as a reference for determining that a foreign substance exists in the hole Provided is a device for detecting foreign matter in a spinneret, wherein the foreign matter is determined to be present in a corresponding discharge hole when it is determined that the area value is smaller than a numerical area value. .

  Further, as means for solving the above-mentioned problem, “an illumination and a scanning camera are arranged opposite to each other across a spinneret having a large number of discharge holes, and inspection light is emitted from the irradiation. The inspection light passing through a plurality of ejection holes is optically enlarged and images are captured by the scan camera to obtain a plurality of image data groups, and the image data groups are combined. Creating at least one composite image data for a large number of ejection holes, and using the gradations of light and darkness of the pixel groups included in the composite image data as a reference, a “bright” and a “dark” Binarization processing is performed for each of these values, and when the pixel group determined to be “bright” is a continuous aggregate, it is recognized as a discharge hole, and “bright” is recognized for each of the recognized discharge holes. The number of pixels in the pixel group Calculated as a value, and when it is determined that the area value is smaller than the area value consisting of the number of pixels set in advance as a reference for determining that a foreign substance exists in the hole, there is a foreign substance in the corresponding discharge hole. Then, there is provided a “method for detecting foreign matter in a hole of a spinneret” characterized in that it is discriminated.

  At this time, as the “method for detecting foreign matter in the hole of the spinneret”, the “passing through a pair of positioning holes drilled in a step portion provided at a position one step lower than the polymer discharge surface of the spinneret” Inspection light is imaged by the scan camera, image position information is uniquely acquired from the image data derived from the positioning hole included in the composite image data, and obtained from the composite image data based on the image position information uniquely. The position information of each discharge hole thus corrected is corrected, the corrected position information of each discharge hole and the position information of each discharge hole stored as the spinneret design data are associated one-to-one and obtained from the composite image data. It is preferable in order to solve the problem according to the present invention that the specified discharge holes are identified with the discharge holes on the spinneret design data.

  Further, as the “method for detecting foreign matter in the spinneret hole”, “bright” is used to identify each discharge hole from the composite image data with the center coordinates of each discharge hole included in the spinneret design data as the center. A circular “region of interest” is set so that each set of pixels identified as “inside” is included therein, and “dark” is determined from a plurality of locations on the outer periphery of each region of interest toward the center of the region of interest. Each of the detected pixels is continuously searched, the pixels determined to be “dark” are exhausted, pixels that are determined to be “bright” are detected, and when pixels that are determined to be “bright” are detected, the corresponding pixels are detected. The position from the boundary position and the distance from each boundary position to the center of the region of interest is calculated as a radius value, and the average radius value is calculated by averaging all the radius values. If the value is smaller than the value, There to exist recognize "it is more preferable in order to solve the problems according to the present invention.

  According to the present invention described above, it is not necessary to inspect a large number of discharge hole groups perforated in the base for each hole, and foreign matter in a hole is detected for a large number of discharge hole groups at a time by image data processing. Therefore, the inspection of foreign matter in the discharge holes can be performed quickly and in a short time. Of course, there is a remarkable effect that the inspection of the foreign matter in the hole can be automatically performed without depending on the naked eye of the inspector.

  In the present invention, the foreign matter adhering in the circular discharge hole formed in the base is inspected using the inspection device for foreign matter in the hole. Therefore, an inspection apparatus for foreign matter in a hole that can be suitably used in the present invention will be described with reference to FIG.

  In FIG. 1, the symbol Ca is a spinneret, and a number of circular discharge holes H are formed in the spinneret Ca as shown. In the inspection apparatus 1 for foreign matter in a hole according to the present invention, illumination 11 is irradiated from below to each discharge hole H drilled in the spinneret Ca (hereinafter also simply referred to as “base Ca”). However, as illustrated in FIG. 1, the illumination 11 is opposed to a line scan camera 3 (described later) in the vertical direction with a spinneret Ca having a discharge hole H as an inspection target interposed therebetween. Is provided.

  Therefore, the light emitted from the illumination 11 provided below becomes the passing light that has passed through each discharge hole H of the base Ca, and this passing light is optically magnified by the magnifying lens 4, and the magnified image is directed upward. The image is taken from the front by the line scan camera 3 provided. In this way, if the base Ca is moved in conjunction with the line scan camera 3, the passing light from each discharge hole H is imaged, and the obtained imaging data is subjected to image processing, the residual in the discharge hole H Can be automatically inspected for foreign matter.

  However, normally, a large number of discharge holes H are formed in the base Ca, and it is necessary to inspect the foreign matter in the holes for all of the formed discharge holes H. However, the in-hole foreign matter in all the discharge holes H cannot be inspected only by the combination of the line scan camera 3 and the illumination 11 provided opposite thereto. This is because the line scan camera 3 provided with the magnifying lens 4 can only capture images of a limited perforated area because the range of capturing images is limited. As a matter of course, the magnification of the image of the magnifying lens 4 should be a value that can identify foreign matter adhering to the ejection hole H.

  Therefore, the inspection apparatus 1 for foreign matter in a hole according to the present invention (in the following description, it may be simply abbreviated as “inspection apparatus 1”) can cover imaging of all perforated areas of the base Ca. And a mechanism for moving the base Ca. That is, the inspection apparatus 1 of the present invention includes a base mounting base 12 on which the base Ca is placed, and irradiates the inspection light toward the base Ca from the illumination 11 disposed below the base mounting base 12. ing.

  In addition, slide members 5 and 6 that can slide independently in the two axial directions of the X axis and the Y axis that are three-dimensionally crossed with each other are attached to the base mounting base 12. Accordingly, the base mounting base 12 on which the base Ca is placed is driven to be slidable (slidable) in the X-axis direction and the Y-axis direction by the two linear servo motors that drive the slide members 5 and 6, respectively. It is the composition which becomes. That is, the base Ca can be moved two-dimensionally along the scanning direction of the line scan camera 3 by the slide members 5 and 6 that can slide independently of each other in the two axial directions of the X axis and the Y axis. Yes.

  In the embodiment of the present invention, a line scan camera is employed. However, it is not essential that the scan camera is a line scan camera. As long as the gist of the present invention is satisfied, other embodiments are used. It goes without saying that can be adopted. However, in this embodiment, a large number of pixels included in the line scan camera are arranged in a linear direction (for example, the X-axis direction), that is, in a one-dimensional direction, and a direction orthogonal to the arrangement direction of the pixels ( For example, image processing is performed by moving the base Ca at a constant speed in the Y-axis direction with respect to the X-axis direction, continuously capturing images at a predetermined cycle, and synthesizing the captured images into a planar image. To obtain composite image data for

  Here, the drive control of the slide members 5 and 6 is performed by a servo controller 9 connected to each servo motor for driving them. That is, the servo controller 9 applies the number of drive pulses corresponding to the required slide amount to the servo motors that drive the slide members 5 and 6, and slides the slide members 5 and 6 by the required amount. To be controlled. Accordingly, control is performed to move the base Ca to a target position at an arbitrary control speed in accordance with the scanning cycle of the line scan camera 3.

  The line scan camera 3, the slide members 5 and 6, the illumination 11, the base mounting base 12 and the like are attached to the support base 2 as illustrated in FIG. At this time, the illumination 11 attached to the support base 2 will be further described. The illumination 11 has a long life, hardly generates heat, and needs to irradiate the entire imaging range of the line scan camera 3. In view of the above, it is preferable to use LED flat illumination (planar LED illumination) using a plurality of light emitting diodes (LEDs) capable of uniformly irradiating a wide area with high luminance.

  This is because, by using the flat LED illumination 11, for example, even if it is a discharge hole H group having a hole diameter of 1 mm or less drilled in the spinneret Ca having a thickness of about several centimeters, it is irradiated in a planar shape. This is because the inspection light easily passes through all the ejection holes H group located in the formed region. In addition, as a line scan camera 3 that captures the passing light from such a flat LED illumination 11, in the example of the present invention, a single-focus optical magnifying lens 4 is mounted, and noise reduction can be expected. A so-called “megapixel” line scan camera 3 composed of many pixels was used.

  In this way, in the embodiment according to the inspection apparatus 1 of the present invention illustrated in FIG. 1, the base Ca placed on the base mounting base 12 installed on the slide members 5, 6 is replaced with the line scan camera 3. It is possible to move in the scanning direction by a necessary distance at a speed according to the imaging cycle of the line scan camera 3. And by this, the inspection light emitted from the illumination 11 is received by the line scan camera 3 through the discharge hole H group drilled in the base Ca, and is obtained in the perforated region of the base Ca by obtaining composite image data Inspection of foreign matter in the discharge hole H becomes possible.

  Of course, the inspection light imaged to obtain composite image data in this way does not limit the imaging range to the individual ejection holes H, but passes through a plurality of target ejection holes H. is there. Therefore, by performing image processing at once on the composite image data composed of the image obtained by capturing the inspection light imaged in this way, a group of ejection holes is used instead of inspection by sequential image processing for each hole as in the prior art. It is possible to inspect for the presence or absence of foreign matter in the hole.

  As described above, in the present invention, the perforated region of the base Ca is divided into a plurality of regions, and the line scan camera 3 is scanned and moved at least once or a plurality of times with respect to these regions. By taking an image in (1), it is a great feature that synthetic image data required for simultaneously inspecting a plurality of discharge holes H is obtained for a plurality of discharge holes H.

  Therefore, in order to achieve the goal of obtaining such composite image data that can be processed, it can be moved along the X and Y axes by two servo motors optimally controlled by the servo controller 9. Therefore, it is required to accurately position and move the slide members 5 and 6 set to the predetermined positions. Therefore, the movement amount (slide amount) of the slide members 5 and 6 is calculated in advance based on the design dimension of the drilling area of the base Ca, and is stored in the computer 10 as a program. It is necessary to keep.

  In this way, based on information stored in the computer 10 (such as the amount of movement of the slide members 5 and 6), each servo motor is driven via the servo controller 9 to accurately move the slide members 5 and 6. Positioning control can be performed, and a predetermined number of image data can be obtained at a predetermined position.

  At the same time, the appropriate slide speeds of the slide members 5 and 6 are calculated according to the scanning cycle of the line scan camera 3 and stored in the computer 10, and based on this stored information (slide speed, etc.) The servo controller 9 also controls the moving speed of the slide members 5 and 6. Therefore, the computer 10, the servo controller 9, the slide members 5 and 6 and the like constitute “positioning driving means” that accurately controls the position at which the scan camera 3 is scanned and the image data is captured.

  That is, the number of pulses input to the X-axis and Y-axis servomotors that drive the slide members 5 and 6 is calculated as described above and stored in the computer 10. Then, based on the information stored in the computer 10, the number of pulses is input to each servo motor as a command value at a necessary timing, and the base Ca is set at a target speed in accordance with the scanning cycle of the line scan camera 3. After moving to a target position and obtaining necessary image data groups, these image data groups can be combined to obtain combined image data.

  In this way, when an image data group consisting of inspection light that has passed through a large number of circular discharge holes H as inspection targets is obtained by scanning with the line scan camera 3, these image data groups are stored in the image processing device 8. By executing the capturing process and performing the composite image creation process, composite image data can be obtained. Then, the presence determination of the foreign matter adhering to the inner wall surfaces of the numerous discharge holes H formed in the base Ca can be performed from the composite image data by one image processing.

  Therefore, compared to the method of inspecting the discharge holes H one by one and detecting foreign matter in the holes corresponding to the individual image data obtained for each discharge hole H as in the prior art, this Since the inspection apparatus 1 of the invention can inspect the foreign matter in a large number of discharge holes H at a time from a small amount of composite image data, the detection processing of the foreign matter in the hole can be performed in a shorter time and efficiently.

  However, the foreign matter in the hole adheres to any position along the length direction (depth direction) of the discharge hole H. That is, foreign matter may adhere to a position immediately after the polymer flows into the discharge hole H, or may adhere to a position immediately before the polymer flows out of the discharge hole H. In consideration of such points, the image data captured by the line scan camera 3 is composed of a plurality of image data groups that are focused along the length direction (depth direction) of the discharge hole H, respectively, as composite image data. It is preferable to use one. For this purpose, it is desirable to provide a function that allows the focal length of the line scan camera 3 to be adjusted at a plurality of locations. The operation of the line scan camera 3 on the entire surface of the base Ca is performed whenever the focal length of the line scan camera 3 is changed. It is desirable to do.

  Hereinafter, the detection processing of the foreign matter existing inside each of the large number of discharge holes H will be described in more detail with reference to FIG. FIG. 2 is a flowchart schematically showing a processing procedure for detecting foreign matter adhering to the inside of a large number of discharge holes H having a circular cross section formed in the base Ca by image processing.

  As can be seen from this flowchart, the first process is performed by the slide members 5 and 6 described above in order to capture the light projected from the illumination 11 and simultaneously passing through the plurality of ejection hole groups H as image data. The cap Ca is moved to a necessary position and, for example, a megapixel line scan camera 3 is scanned to capture an image data group (step S1). Next, the image data group photographed by the line scan camera 3 in this way is read into the image processing device 8 and synthesized as synthesized image data, and the synthesized synthesized image data is processed (step S2).

  Next, when all the pixels included in the synthesized image data synthesized in this way are assigned to a threshold value (for example, 256 gradations) corresponding to a predetermined gradation number (for example, 256 gradations), With reference to the intermediate gradation value as a threshold value, a light / dark process, that is, a binarization process is performed to separate the brightness of each pixel into “bright” and “dark” (step S3).

  In the composite image data after binarization obtained by this binarization processing (brightness / darkness processing), the pixel group recognized as “bright” passes through the ejection holes H that are through holes without blocking. Can be regarded as the detected area. Therefore, an accurate existence region of the discharge hole H can be determined by image processing from the aggregate of all pixels recognized as “bright”. Based on such a principle, first, an accurate presence region of the discharge hole H is determined, and the presence confirmation process of the foreign matter in the hole is performed in the determined discharge hole existence region.

  Specifically, in the embodiment of the confirmation of the discharge hole position by the light / dark process, for example, “1” is assigned to all pixels determined to be “bright”, and for example, all pixels determined to be “dark” The binarization is performed by assigning “0”. At this time, the pixel portion determined to be “dark” is a portion where the discharge hole H does not exist.

  However, with respect to the individual discharge holes H to be subjected to image processing in this way, unless the operator accurately positions and places the specific base Ca to be inspected on the base mounting base 12, the base Ca In such a polymer discharge surface, there is a situation in which it is not possible to specify specifically at which position the discharge hole H is drilled.

  However, if the work of accurately positioning and mounting the base Ca on the base 12 is imposed on the worker, it is extremely difficult to avoid the occurrence of human error due to human factors. Attempting to eliminate these factors places excessive pressure and burden on the workers.

  Therefore, the operator can perform basic operations such as the vertical direction or the horizontal direction of the base Ca without imposing on the inspector the work of positioning and mounting the base Ca on the base mounting base 12 very accurately. It is necessary to ensure that the inspection can be performed satisfactorily even if the base Ca is placed on the base 12 in a vague manner without making a mistake in the direction. Hereinafter, such processing will be described with reference to FIG.

  FIG. 3 is a schematic plan view of the base Ca as viewed from the polymer discharge side. FIG. 3A shows a case where the base Ca is placed on the base mounting base 12 without error and image data is collected. (That is, this is the standard for data processing), and FIG. 3B illustrates the case where the base Ca is appropriately placed on the base mounting base 12 and image data is collected. It is.

In the embodiment of the base Ca of FIGS. 3A and 3B, on the one hand, as shown in the drawing, a large number of discharge holes H drilled in the base Ca are opened on the polymer discharge surface, and on the other hand, A pair of positioning holes P ₁ and P ₂ that are completely different from the discharge hole H penetrate the base Ca in a step part provided with a step that is one step lower than the polymer discharge surface (see the shape of the base Ca in FIG. 1). It is drilled at. Note that these pair of positioning holes P ₁ and P ₂ are not involved in the discharge of the polymer, but are used for in-hole foreign matter inspection of the discharge hole H formed in the base Ca.

Here, in the embodiment shown in FIG. 3A, the pair of positioning holes P ₁ and P ₂ has two central coordinates O _o1 (X _oo1 , Y _oo1 ) and O of the positioning holes P ₁ and P _2. A reference straight line L that connects _o2 (X _oo2 , Y _oo2 ) includes a base center point O, and the base center point O is point-symmetrically formed so as to face each other.

The reason for drilling a pair of positioning holes P ₁ and P ₂ are, by synthesized from the image data of the pair positioning holes P ₁ and P ₂ described above, and uniquely the reference straight line L from the composite image data This is because the center point O of the base can be determined. In this way, even in the case of composite image data obtained when the base Ca is placed on the base mounting base 12 in a vague manner and appropriately, individual discharge holes H existing in the composite image data are specifically identified. Because it can.

  The processing for specifically specifying the individual ejection holes H described above corresponds to “image processing region correction processing” in step S4 in the flowchart of FIG. This process will be described below.

As already described, the composite image data includes image data relating to the pair of positioning holes P ₁ and P ₂ . That is, the image data is related to the inspection light that has passed through the positioning holes P ₁ and P ₂ when the illumination 11 is applied from below the base Ca. Moreover, since this image data is completely different from the image data related to the discharge hole H group drilled on the polymer discharge surface of the base Ca, it is data existing in the stepped portion of the base Ca, and therefore from the composite image data. These data can be easily separated and extracted.

For example, since there is nothing to block the inspection light in the area outside the outer shape (contour) of the base Ca, the inspection light always passes through these outer areas, so the line scan camera 3 can detect the inspection light. I can do it. However, in a portion where there are cap Ca, except where the discharge hole H and the positioning holes P ₁ and P ₂ are present, the inspection light by mouth Ca becomes being blocked completely. Therefore, the inspection light is not detected by the line scan camera 3 in such a portion.

Therefore, it will be easily understood by those skilled in the art that the outer shape (contour) C of the base Ca can be easily determined from the composite image data by image processing without needing to explain the detailed image processing method here. . Then, it can be seen that the image data relating to the pair of positioning holes P ₁ and P ₂ drilled at a predetermined distance from the outer shape (contour) C of the base Ca can be easily specified at the step portion of the base Ca.

As described above, when the image data relating to the pair of positioning holes P ₁ and P ₂ is specified, the detailed description is omitted here, and as will be described later, how to determine the center coordinates of each discharge hole H By the same method, two center coordinates O _o1 (X _oo1 , Y _oo1 ) and O _o2 (X _oo2 , Y _oo2 ) of the pair of positioning holes P ₁ and P ₂ can be obtained. Then, the reference straight line L connecting the two central coordinates O _o1 (X _oo1 , Y _oo1 ) and O _o2 (X _oo2 , Y _oo2 ) can also be obtained. Furthermore, the base center point O ′ can be obtained by calculating the midpoint coordinates of the two central coordinates O _o1 (X _oo1 , Y _oo1 ) and O _o2 (X _oo2 , Y _oo2 ).

  However, the base center point O ′ obtained in this way is different from the case where the base Ca is accurately positioned on the base mounting base 12 as illustrated in FIG. That is, as illustrated in FIG. 3B, the base Ca is mounted on the base mounting base 12 while being rotated by a rotation angle θ °, and the base Ca is also precisely connected to the base mounting point 12. It is mounted at a position shifted compared to the base center point O (which is also the base base point O used as a reference) when positioned and mounted above.

  Therefore, since it is possible to calculate by calculation that the base center point O serving as a reference is shifted to the base center point O ′ by the processing as described above, with respect to the composite image data that is first captured and combined in the image processing device 8. The composite image data is translated so that the base center point O ′ coincides with the base center point O serving as a reference.

  Also, regarding the deviation angle θ °, the reference straight line L and the reference straight line L ′ between the reference straight line L when mounted at an accurate position and the reference straight line L ′ when mounted at a shifted position are It can be determined as the angle of intersection between. Therefore, even in such a case, if the entire obtained image data is corrected by rotating by an angle θ °, it can be handled in the same manner as the entire image data when the base Ca is attached at an accurate position. Yes (step S4).

That is, if the image processing performed in step S4 is specifically illustrated, first, two center coordinates O _o1 (X _oo1 , Y _oo1 ) and O _o2 (X _oo2 , Y) for the pair of positioning holes P ₁ and P ₂ are _used . _{Using oo2} ), the coordinate value (X _o , Y _o ) of the base center point O ′ is obtained from the following equation (1) for _obtaining the midpoint.

Then, when the positional deviation between the coordinate values in relation to the standard cap center point O which had been stored as the database is going on, the coordinate values of the position shift amount of the (t _X, t _Y) translated To the reference center point O. Then, by performing coordinate rotation (θ °) around the base center point O serving as a reference, it can be stored in advance in the database and can be associated with the reference coordinates of each discharge hole H. That is, the image processing in step S4 performs affine transformation defined by the following equation (2). However, in the following formula (2), a, b, c, and d are a = cos θ, b = −sin θ, c = sin θ, d = cos θ, and t _X and t _Y are when the coordinates are moved in parallel. An x-coordinate component and a y-coordinate component are respectively represented.

  By the way, before performing the image processing (step S4) as described above, the above-described binarization processing (step S3) is performed on the composite image data captured by the line scan camera 3. Therefore, a method for inspecting foreign matter in the discharge hole H formed in the base Ca will be described in detail by returning to the binarization process (step S3).

In the binarization process in step S3, the above-described binarization process is performed on all the pixel data included in the outer shape (contour) C of the base Ca, whereby the pixel group determined to be “bright” It can be regarded as a region where the individual discharge holes H or the positioning holes P ₁ and P ₂ exist. Note that pixel data relating to the positioning holes P ₁ and P ₂ in the pixel group determined to be “bright” exists in the stepped portion of the base Ca as described above, and the “image processing area” in step S4. This process is related only to the “correction process”. Therefore, the image data processing related to the pixel data related to each discharge hole H can be clearly distinguished from the processing, and therefore, in the following description, only the image processing for the pixel data related to each discharge hole H will be described. To do.

  As described above, the pixel data relating to each ejection hole H determined as “bright” in the binarization process in step S3 is mixed with noise and is not an area where the ejection hole H exists. In some cases, the discharge hole H may be regarded as an existing region. Therefore, by this binarization process (step S3), ““ bright ”:“ 1 ”” is continuously converted into a plurality of chunks from all the pixel data groups distributed to ““ bright ”:“ 1 ””. And detect the existing location. Such a lump is referred to as “particle” in the present specification.

  Then, since the “particle” is a continuous aggregate composed of a plurality of ““ bright ”:“ 1 ”” clusters, if such “aggregate” is detected, the “particle” happens to be “ “Bright”: Not determined as “1”, but can be regarded as a pixel group that has detected light that has passed through the ejection holes H reliably. Therefore, since the individual “particles” recognized in this way can be recognized as “particles” derived from the light that has passed through the respective discharge holes H, the respective positions where the “particles” exist are recognized. By detecting this, the position of each discharge hole H can be detected.

  In this way, when the position of each discharge hole H is recognized by image processing, the second processing is then performed. This process is a process for detecting foreign substances included in the plurality of image data captured in the image processing apparatus 8 and attached to the wall surfaces of the plurality of discharge holes H whose existence areas are specified. In this process, in order to accurately detect the presence of foreign matter in the hole, two processes of “a hole area determination process” according to step S5 and a “circular hole shape detection process” according to step S6 described below are performed. It is made up of.

[Pore area discrimination processing]
First, as described above, a process of calculating the area value of each discharge hole H from each “particle” data detected as a ““ bright ”:“ 1 ”” lump is performed. This calculation process is a process of calculating an area value of each “particle” portion, that is, a spread of ““ bright ”:“ 1 ””, that is, a spread of an aggregate (the number of pixels constituting each “particle”). . The number of pixels of each “particle” obtained by this process corresponds to the area value of each discharge hole H on a one-to-one basis. Therefore, the number of pixels of each “particle” is regarded as the area value of each discharge hole H. Processing to determine the presence of foreign matter in the hole is performed.

  That is, if there is a foreign substance in the discharge hole H, the inspection light passing through the discharge hole H is blocked by this foreign substance, so that the pixel portion of the line scan camera 3 provided in the portion that receives the blocked inspection light Since the light does not reach, the number of pixels judged as ““ bright ”:“ 1 ”” decreases accordingly. That is, since the area value is small, it is possible to easily detect the foreign matter in the hole as compared with a reference area value (a value that is determined in advance through experiments or the like) that can be determined to be normal. In addition, such processing can be performed at once for all the ejection holes H existing in the perforated region covered by the image data. Therefore, it is not necessary to inspect the foreign matter in each hole as in the prior art.

At this time, it is important to simultaneously perform processing for obtaining the center coordinates of the respective discharge holes H. Note that this process assumes that there are n total pixels allocated to ““ bright ”:“ 1 ”” constituting each particle, and the X coordinate of an arbitrary pixel in each “particle”. When the X and Y coordinates are represented by (X _i , Y _i ), the coordinates (X _oi , Y _oi ) of the center position O _i of any “particle (discharge hole H)” are as shown in the following equation (3) The center coordinates O _i (X _oi , Y _oi ) of the discharge hole H are obtained by using what can be expressed as follows.

In the following description of the embodiment, the center coordinates O _i (X _oi , Y _oi ) of the discharge holes H are obtained in this way, and the center coordinates O of all the discharge holes H obtained at this time are obtained. _i (X _oi , Y _oi ) is stored in a storage means (not shown) of the computer 10 and is used again when the in-hole foreign matter inspection of each discharge hole H is performed. Further, as already described, the center coordinates of the positioning holes P ₁ and P ₂ are also obtained in this way.

  Next, in the present invention, the “circular hole shape detection process” according to step S6 is performed together with the “inside hole area determination process” according to step S5 in each discharge hole H described above. Therefore, the “circular hole shape detection process” according to step S6 will be described below.

[Circular shape detection processing]
In the “circular hole shape detection process” according to step S6, all the discharge holes H obtained by performing the affine transformation defined by the equation (2) and obtaining the existence region of each discharge hole H as “particles” from the composite image data. The center position coordinates of each discharge hole H calculated from the design data of the base Ca previously stored as a database in the image processing apparatus 8 in combination with the position confirmation of the center coordinates O _i (X _oi , Y _oi ) This is to check the positional deviation between O _ri (X _roi , Y _roi ). However, the data related to the center position coordinates O _ri (X _roi , Y _roi ) of each discharge hole H determined from the design data of the base Ca is obtained by drilling each discharge hole H in the base Ca at the designed position. In addition, as long as the `` image processing area correction process '' based on the affine transformation defined in the above equation (2) is accurately performed, the existence positions of all the discharge holes H are expressed very accurately. I can say that.

However, if the interval between the discharge holes H group formed in the base Ca is short, the number of the discharge holes H group is extremely large, or the perforation area of the discharge hole H group is too large, the design data of the base Ca can be used. After the data related to the center position coordinates O _ri (X _roi , Y _roi ) of each ejection hole H and the “image processing area correction process” based on the affine transformation defined in equation (2) There is a case where a slight positional deviation occurs between the center position coordinates O _ri (X _roi , Y _roi ) of each discharge hole H, and the two cannot be associated with each other.

  Further, it is necessary to check whether or not the “in-hole area determination process” according to step S5 is normally performed on the “particles” obtained as described above. For example, when the discharge hole H is completely blocked by foreign matter, there is a pixel that should be determined to be “bright” in the binarization process according to step S2 at a place where “particles” should exist. Will not. Therefore, even in such a case, it is necessary to process normally as a foreign substance existing in the hole.

Therefore, as illustrated in FIG. 4, “particles relating to each discharge hole H obtained as image data with the center position coordinates O _ri (X _roi , Y _roi ) determined from the design data of the base Ca as the center. The circular “region of interest R _Oi ” is set so as to include “ However, in the interior of the "region of interest R _Oi", to contain the recognized pixel group as "an area where the discharge hole H is present", "region of interest R _Oi" is sufficiently with some margin It is set large. Then, even if there is a slight shift in the image data relating to each of the above-described ejection holes H that has been taken in, the “region of interest R _Oi ” can be overlaid so as to reliably include each.

As described above, when the setting of the “region of interest R _Oi ” is completed, the outer periphery side of the “region of interest R _Oi ” in the direction of the arrow indicated by the directed line segment in FIG. The distance from the circle) to the exhaustion of the pixels determined as “not in the region where the discharge holes H exist” is obtained. In other words, from the “multiple azimuths (12 azimuths in the example of FIG. 4)” set on the outer periphery of the “region of interest R _Oi ” toward the center position coordinates O _i (X _oi , Y _oi ) radially, “discharge” A search is made for a boundary position (black circle) where pixels ("dark part" in FIG. 4) determined as "not an area where the hole H exists" are exhausted.

Specifically, as shown in FIG. 4, it is located on the outer periphery of the region of interest R _Oi that is equally divided into m azimuths (12 azimuths in the example of FIG. 4) obtained by equally dividing 360 ° that is all directions. Positions indicated by black circles where pixels that have been identified as “not in the area where the discharge holes H are present” (pixels indicated by “dark”) are exhausted from the twelve white circles to the center O _i (Boundary coordinates) is detected. Then, a distance from the center position coordinate O _i (X _oi , Y _oi ) to a position (boundary coordinate) indicated by a black circle (this “distance” is referred to as “radius value” in the present invention) is obtained. That is, as shown, the radius value R _1, R _2, ..., respectively obtained the R _m, further, these radius value R _1, R _2, ..., by the R _m the following equation (4), the mean radius _Rave is obtained (step S6).

Even if a slight misalignment occurs when the base Ca is inspected by the image processing according to step S6, if there is a discharge hole H in the region of interest R _Oi , the average radius value R calculated by the equation (4) _{Using ave} , the presence of foreign matter in the discharge hole H can be reconfirmed. That is, when there is a foreign substance in a hole in a certain discharge hole H, the average radius value R _ave is smaller than the reference radial value R _{ref as} compared with the “reference radius value R _ref when no foreign substance exists in the hole”. Become. Therefore, it is possible to reconfirm the foreign matter in the hole by performing such processing. However, the reference radius value R _ref used for comparison differs depending on how large the foreign substance in the hole is detected, so that the value should be set appropriately according to the purpose. Needless to say.

Even if a slight misalignment occurs when the base Ca is inspected by the image processing according to step S6, since the discharge hole H exists in the region of interest R _Oi , the discharge is performed using the average radius value R _ave. Presence of the hole H and foreign matter in the hole can be confirmed reliably. When the discharge hole H is completely closed, there is no “pixel assigned to“ bright ”:“ 1 ”indicating the region where the discharge hole H is present” in the region of interest R _Oi ” The radius value R _ave is 0.0. Therefore, in such a case, the particular discharge hole H is initially are guaranteed to be contained in the interior of the region of interest R _Oi, thereon, "" Akira ":" 1 "" It is self-evident that no pixel exists. Therefore, in this case, the specific discharge hole H can be determined as a defective hole that is completely blocked by foreign matter. At that time, the center position coordinates of the defective hole are stored in a storage area of a computer.

However, it is not intended to detect the presence of foreign matter in the holes by these processes, and it may be dedicated to simply obtaining the average radius value _Rave and the presence or absence of a circular object (that is, the discharge hole H). Then, based on the obtained average radius value R _ave , the image data shift is added to the coordinate conversion processing according to the equation (4), and the discharge holes on the database and the target of the image processing are taken into account. The position of the discharge hole obtained from the image data can be further corrected. In this case, it goes without saying that it is preferable to select the discharge hole H located as far as possible from the base center point O ′ as the discharge hole to be used for correcting the image data position.

  In this way, when a foreign substance in the hole is found in the discharge hole H that is the inspection target of the foreign substance in the hole, the position of the discharge hole H is stored in the computer 10. Then, the discharge hole H in which the foreign matter in the hole is detected corresponds exactly one-to-one with the position of the discharge hole H at the initial design as described above. Therefore, the operator can easily take out information related to the specific discharge hole H in which the foreign matter in the hole stored in the computer 10 is detected. Then, based on the information extracted from the computer 10, it is possible to easily remove the foreign matter from the specific discharge hole where the foreign matter in the hole exists.

  As described above, when the residual inspection for foreign matter in a hole is completed for a large number of ejection holes H included in one composite image data, the residual inspection for the foreign matter in the hole is performed from the next composite image data. In addition, the image processing apparatus 8 reads out the next necessary image data (for example, image data having a different focal depth of the magnifying lens as described above), and performs image processing. Then, the in-hole foreign matter inspection in all the discharge holes H of all the image data of the spinneret Ca is finished.

  In the above description, in order to inspect the foreign matter in the hole, the image data group obtained by scanning the scan camera 3 over the entire perforated area of the base Ca is combined into one composite image data. Explained. However, in the present invention, there is no reason to limit to one composite image data. Instead of using only one composite image data, composite image data obtained by dividing the composite image data into a plurality of pieces may be used. good. In this case, it is extremely effective to use the divided composite image data particularly when the amount of data of one composite image data is enormous.

  As described in detail above, in the present invention, the foreign substance determination process is performed in two stages. If a foreign substance is detected in the first stage, the subsequent second stage is performed. It is also possible to skip the process. Of course, these two processes may all be performed regardless of the presence or absence of detection of foreign matter in the hole. Furthermore, according to conditions such as the shape of the foreign matter in the hole to be detected, these two processes may be performed independently without being related to each other.

In the present invention, by using the positioning holes P ₁ and P _2, the image processing apparatus 8 is described embodiment for performing image processing as in step S4 by software, rather than in the process according to this software Or by hardware. In this case, for the pair of positioning holes P ₁ and P ₂ , a pair of positioning pins (not shown) that engage with them are accurately positioned and fixed on the base mounting base 12, The positioning holes P ₁ and P ₂ may be engaged with the pair of positioning pins (not shown). By doing so, the base Ca is always set at a predetermined accurate position.

At this time, the size of the hole and the thickness of the positioning pin may be different from each other between the pair of positioning holes P ₁ and P ₂ and the pair of positioning pins (not shown) that are engaged with each other. preferable. Because, by doing so, it is possible to each of the positioning holes P ₁ and P ₂ are engaged only with each particular positioning pins, when mounting the cap Ca to the base mount 12, top and bottom of the mouthpiece Ca This is because it is possible to avoid a situation in which the situation is reversed.

  Next, detection of scratches on the polymer discharge surface of the spinneret Ca will be described. First, the detection method is area discrimination processing. In this process, first, a CCD camera 3 having a very large number of pixels (pixel data) is used to image light projected from the upper illumination 11 and reflected from the polymer discharge surface of the spinneret Ca.

  At this time, as in the case of inspecting the foreign matter in each discharge hole H, because it does not detect the very small residual foreign matter in each discharge hole H, because it detects a scratch generated on the polymer discharge surface, The entire polymer discharge surface of the spinneret Ca may be taken as one image and this image may be used for data processing. However, if smaller scratches are a problem, it is of course possible to divide the polymer discharge surface of the spinneret Ca into several sections and take enlarged images for each divided section. Images may be combined and handled as a single image.

  Next, the threshold value (for example, for example, the brightness gradation is classified into 256 gradations) is read out for each pixel by reading the image data obtained as described above and captured for each pixel. When the image is divided into 256 gradations, the intermediate gradation value is taken as the standard), and the “bright” of the image data obtained by the process of separating the contrast into “bright” and “dark” parts The recognized pixel group is a region where light that has been reflected differently from the normal on the polymer discharge surface of the spinneret Ca is detected.

  In addition, unlike the light reflected from the part finished with good flatness, the reflected light different from the normal is light that is irregularly reflected at the slightly depressed part with scratches, and the binarization described above. In the processing, a pixel group recognized as “dark” is formed. However, in a specific embodiment of the binarization process, for example, “1” is assigned to all pixels determined to be “bright” and “0” is assigned to all pixels determined to be “dark”. Binarization is performed. Therefore, from the aggregate of all pixels recognized as such “dark”, an accurate existence region of a flaw on the polymer discharge surface of the spinneret Ca can be determined by image processing. Note that the pixel portion determined to be “dark” is a portion where there is no scratch on the polymer discharge surface of the spinneret Ca.

  However, even in the “dark” part, the spinneret Ca is not scratched on the spinneret Ca discharge surface, and the spinneret Ca is partially discolored in the use process, and the reflected light in that part may be judged as “dark”. . Therefore, in order to avoid such a misunderstanding, the spinneret Ca is further tilted by about 5 ° from the horizontal direction using the rotation mechanism 7 of the spinneret mounting base 12, and the illumination 11 is irradiated and reflected from above the spinneret Ca. The image processing is also performed on the image obtained by imaging the light, and the computer 10 calculates whether an aggregate of all pixels determined to be “dark” exists at the same position as the binarized image. As a result, if the presence of a flaw is confirmed at the same position, the presence of the flaw is verified and confirmed by projection light having a different projection angle and irradiation light from above, and the polymer discharge of the spinneret Ca is performed. It is also a clearer ground for the fact that there is indeed a scratch on the face.

  However, the pixel data obtained from the reflected light is also determined to be “dark” by the binarization process for a large number of discharge holes H formed in the spinneret Ca. However, as already described, the position where the discharge hole H is present can be clearly recognized in advance when performing image processing. Accordingly, it is needless to say that the pixel data at the position where the ejection hole H exists can be excluded from the object of image processing, and thus can be clearly distinguished from the scratch present on the polymer ejection surface.

  In addition, as a criterion for determining a scratch, for example, when the number of adjacent pixels consecutively connected to a pixel group determined to be “dark” is counted and this number exceeds a “predetermined threshold number”, It can be considered that a scratch has occurred. Alternatively, if a group of pixels recognized as “dark” is counted, the number of pixels is counted, and if the number exceeds a “predetermined threshold number”, it is determined as “scratch”. good. In any case, if the binarized image data can be obtained as described above, it is possible to recognize the scratches generated on the polymer discharge surface by using a data processing means having a known pattern recognition process. Needless to say.

  According to the method for detecting foreign matter in a hole according to the present invention described above, it is possible to determine the scratches generated in the spinneret Ca together with the inspection of the foreign matter in the hole, and by using it together with the foreign matter inspection in the discharge hole. Many operations for inspecting the abnormality of the spinneret Ca can be released from a person (inspection worker).

  As described above, the data after the image processing and the presence / absence of foreign matter in the hole is inspected is stored in the storage device based on the position information of each discharge hole, and the inspection is related after the inspection. It is also possible for the operator to check visually. At that time, as a matter of course, the operator should remove the foreign matter neatly from the discharge hole by using a needle-shaped jig etc. while using a magnifying glass etc. while visually checking. You can also. In addition, according to the present invention, it is possible to easily perform a foreign matter residual inspection in the discharge hole formed in the spinneret used at the time of synthetic fiber production, leading to labor saving or labor cost reduction.

It is a perspective view showing the embodiment of the inspection apparatus of the foreign material in a hole which can be used for this invention. It is the flowchart which showed the execution procedure of the foreign material detection program which can be performed with the computer for detecting the foreign material adhering in the discharge hole by image processing. 1 is a schematic plan view illustrating an embodiment of a spinneret according to the present invention. It is explanatory drawing of the "circular hole shape detection process" in this invention.

Explanation of symbols

S1 to S6: Each processing step for detecting foreign matter adhering in the ejection hole by image processing.

Claims (5)

A spinneret provided with a number of discharge holes, illumination provided on one side of the spinneret, and a scan camera provided opposite to the illumination on the other side of the spinneret, A magnifying lens that is attached to the scan camera and that is projected from the illumination and passes through the ejection hole and that magnifies an image of the inspection light to a predetermined magnification, and a position for scanning the scan camera to capture image data Processing of image data including at least the positioning drive means for accurate positioning control and the perforation area of the ejection hole drilled by the spinneret by the scan camera to detect in-hole foreign matter existing in the numerous ejection holes at a time A device for detecting foreign matter in a hole of a spinneret comprising an image processing device for
Further, the image processing device generates at least one composite image data for a plurality of ejection holes by compositing the image data group, and preliminarily adjusts the brightness gradation of the pixel group included in the composite image data. Perform binarization processing that distributes each value to `` bright '' and `` dark '' based on the set gradation, and if the pixel group determined as `` bright '' is a continuous aggregate, Recognize and calculate the number of pixels of the aggregate of pixels determined to be “bright” for each of the recognized discharge holes as an area value, and the area value is preliminarily used as a reference for determining the presence of foreign matter in the hole. An apparatus for detecting foreign matter in a spinneret, wherein the foreign matter is determined to be present in a corresponding discharge hole when it is determined that the area value is smaller than a set area value.   An illumination and a scan camera are arranged opposite to each other across a spinneret having a large number of discharge holes, and inspection light is projected from the irradiation toward the scan camera and passes through a plurality of discharge holes. The inspection light is optically enlarged and an image is captured by the scan camera to obtain a plurality of image data groups, and the image data groups are combined to form at least one composite for a plurality of ejection holes. A binarization process that creates image data and distributes the brightness gradation of the pixel group included in the composite image data to either “bright” or “dark” values based on a preset gradation When the pixel group determined to be “bright” is a continuous aggregate, it is recognized as a discharge hole, and the number of pixels of the aggregate of pixels determined to be “bright” for each recognized discharge hole is an area value. And the area value is The hole of the spinneret is characterized in that it is determined that there is foreign matter in the corresponding discharge hole when it is determined that the area value is smaller than the area value consisting of a preset number of pixels as a reference for determining that Detection method for foreign matter inside.   The inspection light that has passed through a pair of positioning holes drilled in a step portion provided at a position one step lower than the polymer discharge surface of the spinneret is imaged by the scan camera and is included in the composite image data The image position information is uniquely acquired from the image data derived from the positioning hole, the position information of each discharge hole obtained from the composite image data is corrected based on the image position information uniquely, and each corrected discharge hole is corrected. The position information and the position information of each discharge hole stored as the spinneret design data are in one-to-one correspondence, and the discharge holes obtained from the composite image data are matched with the discharge holes on the spinneret design data. The method for detecting foreign matter in a hole of a spinneret according to claim 2, wherein the foreign matter is specified by being performed.   A circle is formed so that each set of pixels determined to be “bright” for identifying each discharge hole from the composite image data is included in the center with the center coordinates of each discharge hole included in the spinneret design data as the center. Each “region of interest” is set, and pixels that are determined to be “dark” are continuously searched from a plurality of locations on the outer periphery of each region of interest toward the center of the region of interest, and are determined to be “dark”. Pixels that are determined to be “bright” are exhausted, and when a pixel that is determined to be “bright” is detected, the position of the pixel is set as a boundary position, and the center of the region of interest is determined from each boundary position. And calculating the average radius value by averaging all the radius values, and recognizing that foreign matter is present in the hole when the average radius value is smaller than a reference value. Claim 2 or Detection methods hole foreign matter spinneret according to Motomeko 3.   Illuminating the polymer discharge surface of the spinneret, illuminating the polymer discharge surface with the scan camera, imaging the entire polymer discharge surface with the scan camera, and taking at least one of the entire polymer discharge surface Image data is acquired, all pixels included in the image data are binarized on the basis of a preset light / dark gradation that is the center of the acquired image data, and pattern recognition is performed from the binarized pixel group. The method for detecting foreign matter in a hole of a spinneret according to any one of claims 2 to 4, wherein a flaw generated on the polymer discharge surface is detected.

Images