JP2014073628A - Solder printer, and stain inspection method for mask of solder printer - Google Patents

Abstract

An object of the present invention is to provide a solder printing machine and a mask dirt inspection method for a solder printer capable of performing a highly accurate mask stain inspection even when there is a scratch on the surface of the mask.
An area including a pattern hole 5a of a mask 5 is set as an inspection part S, and the inspection part S is imaged in a state where the inspection part S is illuminated from a first direction with respect to the mask 5, thereby surrounding the pattern hole 5a. The first image GZ1 capable of distinguishing the solder Hd adhering to the solder and the region inside the solder Hd from other regions is acquired, and from a second direction different from the first direction with respect to the mask 5 By imaging the examination site S in an illuminated state, a second image GZ2 that can distinguish the solder Hd region in the examination site S from other regions is acquired. Then, the state of the solder Hd in the mask 5 is detected by obtaining a superimposed image GZ3 obtained by superimposing the two images GZ1 and GZ2.
[Selection] Figure 7

Description

  The present invention relates to a solder printer that prints solder on a substrate through a pattern hole of a mask, and a method for inspecting a smudge of a mask of a solder printer.

  The solder printing machine contacts the mask with the pattern hole to the substrate, slides the squeegee on the mask and scrapes the solder on the mask, transfers the solder to the substrate through the pattern hole, and then the mask The board is separated from the board and solder is printed on the board.

  In such a solder printer, the solder adheres to the pattern hole of the mask every time the solder is printed on the substrate. When the solder adheres to the pattern hole, the pattern hole opens. As the area gradually decreases, the printing accuracy of the solder on the board deteriorates. For this reason, conventionally, the mask after the solder is printed on the substrate is imaged by the imaging means, and the state of the solder is inspected based on the obtained image to detect the state of the solder. It is known that the mask cleaning is performed when it exceeds the threshold (for example, Patent Document 1).

JP-A-8-99401

  However, in the conventional mask stain inspection method, if there is a scratch on the surface of the mask, the scratch may be erroneously recognized as solder in the obtained image. There was a problem that it was difficult to do.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a solder printing machine and a mask dirt inspection method for a mask of a solder printer capable of performing highly accurate mask dirt inspection even when the surface of the mask has scratches. To do.

  The solder printer according to claim 1, wherein the mask having a pattern hole is brought into contact with the substrate, and a squeegee is slid on the mask to scrape the solder on the mask. A solder printing machine for printing solder on the substrate by separating the substrate from the mask after transferring the solder to the substrate, and including the pattern hole of the mask after printing the solder on the substrate A first illumination means for illuminating the examination site from a first direction with respect to the mask, and a second illumination for illuminating the examination site from a second direction different from the first direction with respect to the mask. When the inspection part is imaged in a state in which the inspection part is illuminated by the first illumination means, the illumination means is attached to the pattern hole in the inspection part. And a first image capable of distinguishing the area inside the solder from the other areas, and imaging the examination site while the examination site is illuminated by the second illumination means Accordingly, an imaging unit that acquires a second image capable of distinguishing a solder region in the examination region from other regions, the first image acquired by imaging by the imaging unit, and the first image And a solder state detecting means for detecting a solder state in the mask by acquiring a superimposed image obtained by superimposing the two images.

  A solder printer according to a second aspect is the solder printer according to the first aspect, wherein the imaging means is constituted by a monochrome imaging type imaging means.

  A solder printer according to a third aspect is the solder printer according to the first or second aspect, wherein each of the first illumination means and the second illumination means comprises an LED.

  A solder printer according to a fourth aspect is the solder printer according to any one of the first to third aspects, wherein the first direction with respect to the mask is a direction perpendicular to the mask.

  The method for inspecting a smudge of a mask of a solder printing machine according to claim 5, wherein the mask having a pattern hole is brought into contact with a substrate, and a squeegee is slid on the mask to scrape the solder on the mask. A method for inspecting smudges on a mask of a solder printing machine, wherein solder is transferred to the substrate through a pattern hole, and then the solder is printed on the substrate by separating the substrate from the mask and printing the solder on the substrate An area including the pattern hole of the mask after the inspection is used as an inspection part, and the inspection part is imaged in a state where the inspection part is illuminated from a first direction with respect to the mask, whereby the pattern hole in the inspection part is obtained. A first image acquisition step of acquiring a first image capable of distinguishing the solder adhered around and the region inside the solder from other regions; and A second region that can distinguish the solder region in the inspection region from other regions by imaging the inspection region in a state illuminated from a second direction different from the first direction with respect to the disc. A second image acquisition step for acquiring an image, and a superimposed image obtained by superimposing the first image acquired in the first image acquisition step and the second image acquired in the second image acquisition step A solder state detecting step of detecting the state of solder in the mask by acquiring.

  In the present invention, a first image obtained by imaging the inspection site illuminated from the first direction with respect to the mask (the solder adhered around the pattern hole in the inspection site and the area inside the solder is added to the other images. An image that can be distinguished from the region) and a second image (image of solder in the inspection region) obtained by imaging the inspection region in a second direction different from the first direction with respect to the mask. The state of solder in the mask is detected by obtaining a superimposed image obtained by superimposing the region with an image that can be distinguished from other regions). Even if there is a scratch on the surface of the mask and a scratch appears in one of the first and second images, the scratch will not appear in the other image. Since it is possible to remove scratches from the superimposed image, there is no risk that the scratches may be mistakenly recognized as solder even if there are scratches on the mask surface. Dirt inspection can be performed.

1 is an overall configuration diagram of a solder printing machine according to an embodiment of the present invention. 1 is a side view of a solder printer according to an embodiment of the present invention. The front view of the solder printer in one embodiment of the present invention The fragmentary top view of the solder printer in one embodiment of this invention The block diagram of the upper image pick-up part with which the camera unit with which the solder printer in one embodiment of the present invention is provided is provided The flowchart which shows the execution procedure of the solder printing operation | work which the solder printer in one embodiment of this invention performs The flowchart which shows the execution procedure of the dirt inspection work of the mask which the solder printer in one embodiment of this invention performs (A) (b) The figure which shows the state which is imaging the test | inspection site | part on a mask with the camera unit with which the solder printer in one embodiment of this invention is provided. (A) (b) The figure which shows the example of the image which the solder printer in one embodiment of this invention image-processes (A) (b) The figure which shows the example of the image which the solder printer in one embodiment of this invention image-processes (A) (b) (c) The figure which shows the example of the image which the solder printer in one embodiment of this invention image-processes

  Embodiments of the present invention will be described below with reference to the drawings. 1, 2, and 3, the solder printer 1 includes a series of operations for carrying in and holding the substrate 2, transferring the solder Hd to the held substrate 2, and carrying out the substrate 2 to which the solder Hd is transferred. An apparatus that repeatedly executes a process.

  1, 2, and 3, the solder printing machine 1 is provided on a base 3 as a substrate holding unit that conveys, positions, and holds the substrate 2 and a substrate moving unit that moves the held substrate 2. The substrate holding and moving unit 4, the mask 5 that is in contact with the substrate 2 held by the substrate holding and moving unit 4, and the solder Hd that is slid on the mask 5 that is in contact with the upper surface of the substrate 2 and is supplied onto the mask 5 A squeegee unit 6 for transferring the solder Hd to the substrate 2 by scraping, a camera unit 7 provided so as to be movable in the horizontal direction above the mask 5, and a control device 8 for controlling the operation of each part are provided.

  Hereinafter, for convenience of explanation, the horizontal plane direction in which the board 2 is transported in the solder printer 1 is defined as the X-axis direction, the horizontal plane direction orthogonal to the X-axis direction is defined as the Y-axis direction, and the vertical direction is defined as the Z-axis. Further, the Y-axis direction is the front-rear direction of the solder printer 1, and the X-axis direction is the lateral (left-right) direction, and the operator OP (FIG. 4) performs the operation on the solder printer 1 in the front-rear direction (FIG. 4). 1 and the right side of FIG. 2 are the front side of the solder printer 1 and the opposite side is the rear side.

  2 and 3, the substrate holding / moving unit 4 can be moved in a horizontal plane by the relative movement of the Y table 11, the X table 12, and the θ table 13 and can be moved up and down with respect to the θ table 13. The base portion 14, the pair of support columns 15 provided on the upper surface of the base portion 14 and facing each other in the Y-axis direction, the pair of transport conveyors 16 supported by the pair of support columns 15, and the upper portions of the pair of support columns 15 in the Y-axis direction A pair of clamp members 17 (see also FIG. 4) provided so as to be openable and closable and a lower receiving member 18 provided so that the central portion of the base portion 14 can be raised and lowered with respect to the base portion 14.

  The operation of the pair of conveyors 16 supporting both ends of the substrate 2 from below and transporting and positioning in the X-axis direction is the operation control of the substrate holding / moving unit drive mechanism 4M (FIG. 1) including the actuator or the like that is not illustrated by the control device 8. The operation of clamping the both ends of the substrate 2 positioned on the conveyor 16 by opening and closing the pair of clamp members 17 in the Y-axis direction is performed by the control device 8 of the substrate holding and moving unit driving mechanism 4M. This is done by performing operation control (FIG. 1). The operation of the substrate holding and moving unit drive mechanism 4M is controlled by the control device 8 when the lower support member 18 moves up and down with respect to the base portion 14 and supports the central portion of the substrate 2 clamped by the clamp member 17 from below. This is done by performing control (FIG. 1).

  In FIG. 4, the mask 5 has four sides supported by a mask frame 5W made of a rectangular frame member in plan view, and an electrode 2a provided on the substrate 2 in a rectangular area surrounded by the mask frame 5W. The pattern hole 5a corresponding to is provided.

  In FIG. 4, a pair of substrate-side marks 2m are provided at diagonal positions of the substrate 2, and a pair of mask-side marks arranged in correspondence with the substrate-side mark 2m is provided on the mask 5. 5m is provided. When the substrate 2 is brought into contact with the mask 5 in a state in which the substrate side mark 2m and the mask side mark 5m coincide with each other in plan view, the electrode 2a of the substrate 2 and the pattern hole 5a of the mask 5 coincide with each other.

  2 and 3, the squeegee unit 6 includes a squeegee base 21 that is moved in the Y-axis direction by a squeegee unit moving mechanism 6M (FIG. 1) including an actuator (not shown), and a pair of squeegee bases 21 that are attached to the upper surface of the squeegee base 21. The squeegee lifting cylinder 22 includes a pair of front and rear squeegees 23 that can be raised and lowered below the squeegee base 21.

  2 and 3, the camera unit 7 is moved in a horizontal plane by a camera unit moving mechanism 7M (FIG. 1) including an actuator (not shown). The camera unit 7 includes an upper imaging unit 31 with an imaging field of view facing upward and a lower imaging unit 32 with an imaging field of view facing downward. The upper imaging unit 31 and the lower imaging unit 32 have the same configuration. Yes.

  In FIG. 5, the upper imaging unit 31 (the same applies to the lower imaging unit 32) includes a camera unit 7a that images the examination site S and an illumination unit 7b that illuminates the examination site S in the housing 7c. The camera unit 7a is composed of, for example, a CCD image pickup device, and an inexpensive monochrome image pickup type is adopted in addition to a color image pickup type. The inspection site S here is an area including the pattern hole 5a of the mask 5 or the mask side mark 5m after the solder Hd is printed on the substrate 2 for the upper imaging unit 31, and for the lower imaging unit 32. The substrate-side mark 2m provided on the substrate 2.

  In FIG. 5, the illumination unit 7b is configured to illuminate the examination site S from the first direction (perpendicular to the examination site S) by coaxial illumination via a half mirror 7d provided in the housing 7c. First illumination means) and a plurality of light sources 42L arranged on a concentric circle centered on the imaging optical axis 7J of the camera unit 7a in plan view, and the examination site S is different from the first direction. It comprises a second illumination 42 (second illumination means) that illuminates in two directions (a direction in which oblique illumination is performed from a direction surrounding the imaging optical axis 7J of the camera unit 7a). The camera unit 7 can selectively use the first illumination 41 and the second illumination 42 as illumination means for illuminating the examination site S.

  As described above, in the present embodiment, the first illumination 41 of the upper imaging unit 31 uses the region including the pattern hole 5a of the mask 5 after the solder Hd is printed on the substrate 2 as the inspection region S, and the inspection region S is used as the inspection region S. The second illumination 42 illuminates the inspection site S from a second direction different from the first direction with respect to the mask 5.

  Here, the type of the light source 41L of the first illumination 41 and the type of the plurality of light sources 42L of the second illumination 42 are not limited, but the illumination intensity of these light sources 41L and 42L is stable from the start of lighting. It is preferable to use an LED that has a short time to complete and a very small calorific value.

  The movement operation of the base portion 14 provided in the substrate holding and moving unit 4 in the horizontal plane and the raising and lowering operation of the base portion 14 with respect to the θ table 13 are performed by the control device 8 performing operation control of the substrate holding and moving unit driving mechanism 4M. (Fig. 1).

  The movement of the squeegee base 21 provided in the squeegee unit 6 in the Y-axis direction is performed by the control device 8 controlling the operation of the squeegee unit moving mechanism 6M. 8 is performed by controlling the operation of the squeegee lifting cylinder 22 corresponding to each squeegee 23 (FIG. 1).

  The moving operation of the camera unit 7 is performed when the control device 8 controls the operation of the camera unit moving mechanism 7M (FIG. 1), and the first illumination 41 and the second illumination 42 provided in the camera unit 7 are turned on / off. The imaging operation of the camera unit 7a is controlled by the control device 8. Image data obtained by the imaging operation of the camera unit 7a is input to the control device 8 (FIG. 1).

  Next, the execution procedure of the solder printing operation performed by the solder printer 1 will be described using the flowchart of FIG. In the solder printing operation, the control device 8 first loads the board 2 loaded from the outside of the solder printer 1 by the transfer conveyor 16 and positions it at a predetermined work position (step ST1). And while clamping on both sides of the board | substrate 2 with a pair of clamp member 17, the lower receiving member 18 is raised and the board | substrate 2 is hold | maintained (step ST2).

  When the control device 8 holds the substrate 2, the camera unit 7 is moved into the lower region of the mask 5, and the substrate-side mark 2 m provided on the substrate 2 is imaged from above by the lower imaging unit 32, and the substrate-side mark 2 m is captured. Image data is acquired, and then the mask side mark 5m provided on the mask 5 is imaged from below by the upper imaging unit 31 to acquire image data of the mask side mark 5m. Then, image recognition based on the obtained image data of the substrate side mark 2m is performed to calculate the position of the substrate 2, and image recognition based on the image data of the mask side mark 5m is performed to calculate the position of the mask 5.

  After calculating the position of the substrate 2 and the position of the mask 5, the control device 8 moves the camera unit 7 to a position outside the area below the mask 5. Then, based on the calculated position of the substrate 2 and the position of the mask 5, the substrate holding and moving unit 4 is moved so that the substrate side mark 2m is positioned immediately below the mask side mark 5m. As a result, the substrate 2 is aligned with the mask 5 (step ST3).

  The control device 8 raises the base portion 14 of the substrate holding and moving unit 4 after positioning the substrate with respect to the mask 5, and brings the upper surface of the substrate 2 into contact with the lower surface of the mask 5. As a result, the electrode 2a of the substrate 2 and the pattern hole 5a of the mask 5 are matched (step ST4).

  When the substrate 8 is brought into contact with the mask 5, the control device 8 operates the squeegee unit 6 to transfer the solder Hd supplied in advance onto the mask 5 to the electrode 2a of the substrate 2 (step ST5).

  In this solder Hd transfer operation, one squeegee 23 is lowered with respect to the squeegee base 21 and the lower end thereof is brought into contact with the mask 5, and the squeegee base 21 is moved in the horizontal direction (Y-axis direction). 23 is slid on the mask 5.

  Here, when the squeegee base 21 is moved from the front to the rear of the solder printer 1 (from right to left in FIG. 1 and FIG. 2), the squeegee 23 located in front is brought into contact with the mask 5. When squeegeeing is performed and the squeegee base 21 is moved from the rear to the front of the solder printer 1 (from the left to the right in FIG. 1 and FIG. 2), the squeegee 23 located at the rear contacts the mask 5. And squeezing.

  When the transfer operation of the solder Hd is completed, the control device 8 lowers the base portion 14 and separates the substrate 2 from the mask 5 to release the plate (step ST6). As a result, the solder Hd is printed on the electrode 2 a on the substrate 2.

  When the control device 8 releases the plate, the control device 8 releases the holding (clamping) of the substrate 2 by the pair of clamp members 17 (step ST7). And the conveyance conveyor 16 is operated and the board | substrate 2 is carried out to the exterior of the solder printer 1 (step ST8). As a result, the solder printing operation for one board 2 is completed.

  The control device 8 performs a stain inspection of the mask 5 every time the solder printing operation is performed on one to several sheets of the substrate 2 in the manner described above. Hereinafter, the execution procedure of the mask 5 stain inspection work (mask 5 stain inspection method) in the solder printer 1 will be described with reference to the flowchart of FIG.

  First, the control device 8 moves the camera unit 7 to a lower area on the mask 5 after solder printing so that the imaging optical axis 7J of the upper imaging unit 31 passes through the inspection site S on the mask 5 (FIG. 8). (A)). Then, the first illumination 41 is turned on (the second illumination 42 is turned off), and the examination site S is illuminated by the camera unit 7a in a state where the examination site S is illuminated from the first direction with respect to the mask 5 (the vertical direction with respect to the mask 5). The first image GZ1 (FIG. 9A) is acquired by imaging (first image acquisition step of step ST11 shown in FIG. 7).

  In this first image acquisition step, the examination site S is illuminated from the direction perpendicular to the mask 5 and imaged, so that the surface of the mask 5 that is a flat portion in the examination site S appears white in the first image GZ1. The solder Hd, which is the edge and the curved surface, and the area inside the solder Hd (the area surrounded by the solder Hd and the solder Hd) are black images.

  That is, the first image GZ1 obtained in the first image acquisition process of step ST11 is the solder Hd adhering around the pattern hole 5a in the inspection site S and the area inside the solder Hd (solder Hd and the solder thereof). The image can be distinguished from the other regions (the region surrounded by Hd).

  When the control device 8 acquires the first image GZ1 in the first image acquisition step, the image processing unit 8a (FIG. 1) binarizes the first image GZ1 and then reverses the black and white. To obtain a black-and-white inverted image HGZ1 (FIG. 9B).

  After obtaining the black-and-white inverted image HGZ1 as described above, the control device 8 turns off the first illumination 41 and then turns on the second illumination 42, so that the inspection site S is the first direction with respect to the mask 5 In a state where illumination is performed from a different second direction (a direction inclined from a direction perpendicular to the mask 5) (FIG. 8B), the second image GZ2 ( FIG. 10A is acquired (second image acquisition step of step ST12).

  In this second image acquisition step, the inspection site S is illuminated with oblique illumination and imaging is performed, so that the second image GZ2 has the edge portion in the inspection site S and the solder Hd that is a curved surface thereof appear white. The surface of the mask 5, which is a flat portion, and the inner region of the solder Hd are black.

  That is, the second image is an image that can distinguish the area of the solder Hd in the inspection region S from other areas.

  As described above, in the present embodiment, the camera unit 7a of the camera unit 7 images the examination site S in a state where the examination site S is illuminated by the first illumination 41, whereby the pattern hole 5a in the examination site S is obtained. A first image GZ1 that can distinguish the solder Hd attached around the solder Hd and the area inside the solder Hd (the solder Hd and the area surrounded by the solder Hd) from the other areas is obtained and inspected. By capturing an image of the examination site S in a state where the site S is illuminated by the second illumination 42, a second image GZ2 capable of distinguishing the solder Hd region in the examination site S from other regions is obtained. Imaging means.

  When the first image GZ1 (monochrome inverted image HGZ1) and the second image GZ2 are obtained as described above, the control device 8 uses the image processing unit 8a to obtain the first image GZ1 (monochrome inverted image HGZ1). The second image GZ2 is overlaid to obtain a superimposed image GZ3 (superposed image acquisition step of step ST13). Here, as the superimposed image GZ3, only the solder Hd obtained in the first image GZ1 and the area inside the solder Hd (the area surrounded by the solder Hd and the solder Hd) are extracted from the second image GZ2. An image obtained by performing image processing to extract an area inside the solder Hd attached around the pattern hole 5a in the inspection site S as an opening area R of the pattern hole 5a (opening area extraction image; FIG. 10B). Get. Note that the superimposed image GZ3 (opening area extraction image) shown in FIG. 10B is obtained by binarizing the obtained image and then inverting black and white.

  Here, when there is a scratch flaw SC (FIG. 10A) on the surface of the mask 5, the scratch flaw SC appears in white in the second image GZ2 and black in its interior. The scratch flaw SC may appear black in the first image GZ1 (in the black-and-white inverted image HGZ1 the inside is white), but by increasing the intensity of light emitted from the light source 41L, the first scratch G It is possible to prevent scratches from appearing in the image GZ1, and to remove the scratches SC in the superimposed image GZ3 in which the first image GZ1 (black and white inverted image HGZ1) and the second image GZ2 are superimposed. Is possible.

  When the superimposed image GZ3 is obtained as described above, the control device 8 calculates the area of the opening area R of the pattern hole 5a in the superimposed image GZ3 as the target area in the area calculating unit 8b (FIG. 1) ( Step ST14 target area calculation process). Here, the calculation of the area of the target region is performed, for example, by obtaining the product of the number of pixels constituting the target region and the area per pixel.

  After calculating the area of the target region (here, the opening region of each pattern hole 5a in the examination site S) in the target region area calculating step, the control device 8 uses the determination unit 8c (FIG. 1) to calculate the calculated target region area. Is compared with a predetermined reference area to determine the state of the solder Hd around each pattern hole 5a in the inspection site S (solder state determination step of step ST15).

  Here, the size of the area of the target region (the area of the opening region R of the pattern hole 5a) compared with the reference area in the solder state determination step represents the degree of clogging due to the solder Hd of the pattern hole 5a. When the area of the target region calculated in the target region area calculation step (the area of the opening region R of the pattern hole 5a) is less than the reference area, it is determined that the state of the solder Hd is good, and the pattern hole 5a is opened. When the area of the region R exceeds the reference area, it is determined that the state of the solder Hd is defective.

  As described above, in the present embodiment, the control device 8 obtains the superimposed image GZ3 obtained by superimposing the first image GZ1 and the second image GZ2 obtained by imaging by the camera unit 7a, whereby the mask 5 This is a solder state detecting means for detecting the state of the solder Hd.

  After determining the state of the solder Hd around each pattern hole 5a in the inspection site S, the control device 8 determines whether or not the mask 5 is dirty in the stain determination unit 8d (FIG. 1) ( (Step ST16 for mask dirt determination). Specifically, when it is determined that the state of the solder Hd is good in the solder state determination step of step ST15, it is determined that the mask 5 is not dirty, and the state of the solder Hd is determined to be defective. Therefore, it is determined that the mask 5 is dirty. When the control device 8 determines that the mask 5 is dirty, the notification control unit 8e (FIG. 1) uses the notification device 50 (FIG. 1) such as a display device connected to the control device 8 to A notification that the cleaning of the mask 5 is necessary is performed (notifying step of step ST17), and if it is determined that the mask 5 is not dirty, the contamination inspection operation of the mask 5 is terminated.

  When the operator OP receives a notification from the alarm device 50 that the mask 5 needs to be cleaned, the operator OP operates a mask cleaning device (not shown) provided in the solder printer 1 to pattern the lower surface of the mask 5. A mask cleaning operation is performed to remove the solder Hd attached around the hole 5a.

  In the above-described example, the control device 8 obtains an image (opening region extraction image) obtained by extracting the opening region R of the pattern hole 5a as the overlapping image GZ3 in the overlapping image acquisition step of step ST13. The surface of the mask 5 that is a flat part in S is white, and the edge and curved surface part of the solder Hd and the area inside the solder Hd (the area surrounded by the solder Hd and the solder Hd, and the pattern hole 5a The first image GZ1 (FIG. 11 (a)), which is an image in which the opening region R) appears black, and the edge 5 in the inspection site S and the solder Hd, which is a curved surface thereof, appear white, and the mask 5 is a flat portion. And the black and white reversal image HGZ2 (FIG. 11B) of the second image, which is an image in which the surface of the solder Hd and the internal area of the solder Hd appear black, are superimposed. By performing image processing for extracting only the solder Hd obtained in the first image GZ1 and the area inside the solder Hd, an image obtained by extracting the area of the solder Hd attached around the pattern hole 5a in the inspection site S (solder) The region extraction image) may be acquired as a superimposed image GZ3 (FIG. 11C).

  When the solder region extraction image is acquired as the overlay image GZ3 in this way, the control device 8 performs the pattern hole 5a in the overlay image GZ3 (solder region extraction image) in the target region area calculation step of step ST14 described above. The area of the solder Hd around the target area is calculated as the target area. Then, in the solder state determination step of step ST15, the area of the target region (the region of the solder Hd around the pattern hole 5a) calculated in the target region area calculation step is compared with a predetermined reference area, and the inspection region S The state of the solder Hd around each pattern hole 5a is determined.

  Thus, even when an image (solder region extraction image) obtained by extracting the area of the solder Hd attached around the pattern hole 5a in the inspection site S is obtained as the superimposed image GZ3, the superimposed image GZ3 is obtained. As in the case of obtaining an image (opening area extraction image) obtained by extracting an area (opening area R of the pattern hole 5a) of the solder Hd attached around the pattern hole 5a in the inspection site S, at an appropriate time. Mask cleaning work can be performed.

  If there is a scratch flaw SC (FIG. 11B) on the surface of the mask 5, the scratch flaw SC appears white in the second image GZ2 and black in the inside (in the black-and-white inverted image HGZ2). Although the inside may appear black in the first image GZ1, the scratch may not appear in the first image GZ1 by increasing the intensity of light emitted from the light source 41L. In the superimposed image GZ3 obtained by superimposing the first image GZ1 and the second image (black and white inverted image HGZ2), the scratches SC can be removed.

  As described above, according to the solder printer 1 and the method for inspecting the smudges of the mask 5 by the solder printer 1 in the present embodiment, the inspection site S can be obtained by illuminating the mask 5 from the first direction. The first image GZ1 (image that can distinguish the solder Hd attached around the pattern hole 5a in the inspection region S and the region inside the solder Hd from other regions), and the inspection region S as a mask 5 The second image GZ2 obtained by imaging in a state illuminated from a second direction different from the first direction with respect to (the solder Hd region in the examination site S can be distinguished from other regions) ) Is obtained, the state of the solder Hd in the mask 5 is detected. Even if there is a scratch flaw SC on the surface of the mask 5 and the scratch flaw SC appears in one image (first image GZ1) of the first image GZ1 and the second image GZ2, the other This image (second image GZ2) can prevent the scratches SC from appearing, and the scratches SC can be removed from the superimposed image GZ3. Even if there is a case, there is no possibility that this is mistakenly recognized as the solder Hd, and a highly accurate inspection of the mask 5 can be performed.

  Provided are a solder printing machine and a mask dirt inspection method for a mask of a solder printer capable of performing a highly accurate mask dirt inspection even when there is a scratch on the surface of the mask.

DESCRIPTION OF SYMBOLS 1 Solder printer 2 Board | substrate 5 Mask 5a Pattern hole 7a Camera part (imaging means)
8 Control device (solder state detection means)
23 Squeegee 41 First illumination (first illumination means)
42 2nd illumination (2nd illumination means)
S inspection site Hd solder GZ1 first image GZ2 second image GZ3 superimposed image

Claims (5)

A mask having a pattern hole is brought into contact with the substrate, and a squeegee is slid on the mask to scrape the solder on the mask, thereby transferring the solder to the substrate through the pattern hole. A solder printer that prints solder on the board by separating the board from the board,
A region including the pattern hole of the mask after the solder is printed on the substrate as an inspection region, and a first illuminating unit that illuminates the inspection region from a first direction with respect to the mask;
Second illumination means for illuminating the inspection site from a second direction different from the first direction with respect to the mask;
By imaging the inspection part in a state where the inspection part is illuminated by the first illuminating means, the solder adhered around the pattern hole in the inspection part and the region inside the solder are added to the other parts. A first image that can be distinguished from a region is acquired, and the inspection part is imaged in a state where the inspection part is illuminated by the second illuminating means. Imaging means for acquiring a second image capable of distinguishing the region from other regions;
Solder state detecting means for detecting a solder state in the mask by acquiring a superimposed image obtained by superimposing the first image and the second image acquired by imaging by the imaging means. A solder printer characterized by that.   2. The solder printing machine according to claim 1, wherein the image pickup unit comprises a monochrome image pickup type image pickup unit.   The solder printing machine according to claim 1 or 2, wherein each of the first illumination means and the second illumination means has an LED as a light source.   4. The solder printing machine according to claim 1, wherein the first direction with respect to the mask is a direction perpendicular to the mask. A mask having a pattern hole is brought into contact with the substrate, and a squeegee is slid on the mask to scrape the solder on the mask, thereby transferring the solder to the substrate through the pattern hole. A method for inspecting a smudge of a mask of a solder printer that prints solder on the substrate by separating the substrate from the substrate,
The inspection portion is imaged in a state where the region including the pattern hole of the mask after printing the solder on the substrate is an inspection portion and the inspection portion is illuminated from a first direction with respect to the mask. A first image acquisition step of acquiring a first image capable of distinguishing the solder attached around the pattern hole in the part and the region inside the solder from other regions;
The region of solder in the inspection region may be distinguished from other regions by imaging the inspection region in a state where the inspection region is illuminated from a second direction different from the first direction with respect to the mask. A second image acquisition step of acquiring a possible second image;
The state of solder in the mask by acquiring a superimposed image obtained by superimposing the first image acquired in the first image acquisition step and the second image acquired in the second image acquisition step A method for inspecting smudges on a mask of a solder printing machine, comprising: a solder state detecting step of detecting a solder.