JP2006084185A - Imaging method of mounting substrate, inspection method, inspection device, and mounting line - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging method of a mounting substrate capable of connecting accurately images imaged dividedly. <P>SOLUTION: This imaging method includes an imaging step for dividing the mounting substrate P where electronic components E are mounted into a plurality of imaging domains Pg, and imaging by moving successively an imaging means 3 to each imaging domain Pg, to acquire a plurality of divided image data; a synthesizing step for acquiring synthesized image data by connecting the plurality of divided image data; and a correction step for correcting an imaging position to the imaging domain Pg of the imaging means 3 based on a position deviation of each imaging domain in the synthesized image data. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mounting board imaging method, an inspection method and an inspection apparatus, and a mounting line, which are applied when, for example, a mounting board on which an electronic component is mounted by a mounting machine is inspected.

When inspecting a mounting board on which electronic components are mounted by image processing, as shown in Patent Documents 1 to 3, the inspection target part of the mounting board is divided and imaged, and the captured images are joined together to form a composite image. What is created is well known.
JP-A-3-240372 (1 page) Japanese Patent Laid-Open No. 5-1878826 (2 pages, FIGS. 6 and 8) JP-A-9-35047 (2 pages, FIGS. 4 and 8)

  However, the conventional inspection apparatus has a problem in that it is difficult to join captured images with high positional accuracy, and for example, the positional accuracy of the jointed portion decreases in time series.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a mounting board imaging method, a mounting board inspection method, and an inspection apparatus capable of joining divided images with high positional accuracy. And

  The present invention provides the following means.

[1] A method of imaging a mounting board on which electronic components are mounted by an imaging means,
An imaging step of dividing the mounting substrate into a plurality of imaging areas and sequentially moving the imaging means to each imaging area to obtain a plurality of divided imaging data;
A combining step of connecting the plurality of divided imaging data to obtain combined imaging data;
A mounting board imaging method, comprising: a correction step of correcting an imaging position of the imaging means with respect to the imaging area based on a positional deviation amount for each imaging area in the composite imaging data.

  [2] The mounting substrate imaging method according to [1], wherein in the combining step, the plurality of divided imaging data are connected without overlapping.

[3] In the imaging step, the imaging region including the position reference mark given to the mounting substrate is imaged,
In the correction step, position data of a plurality of electronic components in the composite imaging data is obtained with reference to the position reference mark, and the position data is compared with position data of a reference electronic component prepared in advance. 3. The positional deviation amount of each electronic component is calculated, the positional deviation amount of each electronic component is totaled for each imaging region, and the positional deviation amount for each imaging region is calculated. Imaging method for mounting board.

  [4] In the correction step, the correction value for correcting the mounting position by the mounting machine is calculated based on the positional deviation amount in each imaging area in the composite imaging data. The mounting substrate imaging method according to any one of the above.

[5] A mounting board inspection method for inspecting a mounting board on which electronic components are mounted,
Inspection component data is partially extracted from the combined imaging data obtained by the mounting board imaging method described in any one of 1 to 4 above, and an electronic component corresponding to the inspection component data is extracted based on the inspection component data. A method for inspecting a mounting board, wherein the quality is judged.

[6] A mounting board inspection apparatus for inspecting a mounting board on which electronic components are mounted,
Moving means for moving the imaging means relative to the mounting substrate in the X-axis direction and the Y-axis direction parallel to the imaging surface;
6. A mounting board inspection apparatus comprising: control means for controlling driving of the imaging means and the moving means, and executing the inspection method according to item 5.

[7] A mounting line comprising a mounting machine for mounting an electronic component on a substrate, and an inspection device for inspecting the substrate on which the electronic component is mounted by the mounting machine,
7. A mounting line, wherein the inspection device is configured by the mounting substrate inspection device according to item 6.

  [8] The mounting line according to [7], wherein in the correction step, a mounting position by a mounting machine is corrected based on a positional deviation amount in each imaging area in the composite imaging data.

  According to the mounting board imaging method of the above invention [1], the imaging position is corrected based on the positional deviation amount for each imaging area in the composite imaging data, so that the divided images can be connected with high positional accuracy. it can.

  According to the mounting substrate imaging method according to the above invention [2], the imaging efficiency can be improved, the data processing of the overlap portion is not required, and the imaging efficiency can be further improved.

  According to the mounting board imaging method of the above invention [3], the position data of each electronic component is obtained with reference to the position reference mark. Therefore, the position data can be obtained with high accuracy and the divided images are joined together. The position accuracy of the portion can be further improved.

  According to the mounting board imaging method of the invention [4], the mounting position by the mounting machine can also be accurately corrected.

  According to the invention [5], it is possible to provide a mounting board inspection method that exhibits the same effect as described above.

  According to the invention [6], it is possible to provide a mounting board inspection apparatus that exhibits the same effect as described above.

  According to the above inventions [7] and [8], it is possible to provide a mounting line that exhibits the same effects as described above.

  FIG. 1 is a schematic plan view showing a mounting line (mounting system) according to an embodiment of the present invention. As shown in the figure, this mounting line has a mounting machine 6 and an inspection device 10 arranged side by side along the transport line XL of the printed circuit board P.

  The mounting machine 6 is disposed along the transport line XL on the base 61, and conveys the printed circuit board P, and the component supply unit 8 disposed on one side (front side) of both sides of the conveyor 7. And a mounting head unit 9 provided above the base 61.

  The component supply unit 8 includes a plurality of tape feeders 81... Suitable for supplying relatively small chip components.

  Each tape feeder 81 is detachably mounted with a reel on which a tape storing and holding electronic components E such as ICs, transistors, capacitors, and the like at predetermined intervals is detachably attached, and the tape is attached to the tip of the tape feeder 81 from the reel. The chip unit that is intermittently drawn to the side and stored on the tape can be picked up by the head unit 9.

  The head unit 9 is movable in an area including the component supply unit 8 and the mounting position on the printed circuit board P so that components can be picked up from the component supply unit 8 and mounted on the printed circuit board P. Specifically, the head unit 9 is configured to be movable in the X-axis direction (a direction parallel to the transport line XL) and the Y-axis direction (a direction perpendicular to the X-axis direction in a horizontal plane) by a moving unit. .

  The head unit 9 is mounted with a plurality of heads 91 for adsorbing and mounting the electronic component E on the substrate P side by side in the X-axis direction. Each head 91 is driven in the vertical direction (Z-axis direction) by a Z-axis drive means (not shown), and is driven in the rotation direction (R-axis direction) by a rotation drive mechanism as an R-axis drive means. It has become.

  FIG. 2 is a front view of the inspection apparatus 10. FIG. 3 is a side sectional view of the apparatus, and FIGS. 4 to 6 are block diagrams showing the internal structure of the inspection apparatus 10. As shown in these drawings, the inspection apparatus 10 inspects the mounting state of the electronic component E on the mounting board P on which the electronic component E is mounted by the mounting machine 6.

  The inspection apparatus 10 includes a frame that is a base (not shown) supported by a leg member, and a housing 1 is formed on the frame by a plurality of panels that are detachably attached by bolts. An internal conveyor 2 is provided on the frame along the substrate transfer line XL in the housing 1. As shown in FIGS. 4 to 6, the internal conveyor 2 is configured to be movable along the Y-axis direction (front-rear direction) orthogonal to the transport line XL in the horizontal plane by the Y-axis moving means 20. That is, the inner conveyor 2 is attached to a pair of rails 22 arranged along the Y-axis direction so as to be slidable along the rail length direction. Further, the inner conveyor 2 is screwed to a ball screw 23 arranged along the Y-axis direction. When the ball screw 23 is driven to rotate by driving of the motor 24, the inner conveyor 2 moves in the Y-axis direction. It is configured to be. Thus, the internal conveyor 2 is configured to be moved along the Y-axis direction by the Y-axis moving means 20 between the conveyance line XL and the rear part (back part) in the housing 1.

  In addition, on the transfer line XL on both sides of the internal conveyor 2, a carry-in conveyor and a carry-out conveyor (not shown) respectively covered with conveyor covers 11 and 12 are provided. The housing 1 is provided with openings (not shown) through which the carry-in conveyor and the carry-out conveyor pass, respectively. In a state where the internal conveyor 2 is disposed on the transfer line XL, the mounting board P is transferred from the outside of the housing 1 to the internal conveyor 2 by the carry-in conveyor, and the board P on the internal conveyor 2 is transferred to the internal conveyor 2. And it is comprised so that it may carry out to the exterior of the housing 1 with the carrying-out conveyor.

  A camera 3 as an image pickup unit is disposed behind (inner part of) the inner conveyor 2 in the housing 1. The camera 3 is configured to be movable along the X-axis direction parallel to the transport line XL by the X-axis moving means 30. That is, the support member 31 that supports the camera 3 is attached to a pair of rails 32 arranged along the X-axis direction so as to be slidable along the rail length direction. Further, the camera support member 31 is screwed to a ball screw 33 arranged along the X-axis direction. When the ball screw 33 is driven to rotate by driving of the motor 34, the camera 3 is moved in the X-axis direction. It is configured to be moved.

  The camera support member 31 is provided with an illuminating device 35 for illuminating an area imaged by the camera 3.

  FIG. 7 is a block diagram showing a main control system of the inspection apparatus 10. As shown in the figure, in this apparatus, the CPU 5 controls the driving of each driving unit and the like, and the operation described in detail later is automatically executed. In the figure, an input device 41 such as a keyboard is for inputting various information related to the inspection to the inspection device 10, and a display device 42 such as a CRT display is for displaying various information. is there. Furthermore, the storage device 43 stores various data necessary for inspection.

  The image frame memory 51 is divided image data (divided image) obtained via the image input port 52, wide area image data (wide area image) as composite image data (composite image) obtained by processing the image, and Image data such as electronic component data (inspection component data) to be inspected is stored. The memory 53 temporarily stores various data necessary for inspection. Further, the illumination controller 54 controls the driving of the illumination device 35 during imaging by the camera 3, and the motor controller 55 and the motor amplifier 56 control the driving of the X-axis moving unit 30 and the Y-axis moving unit 20 to control the camera. 3 is moved relative to the mounting substrate P in the XY-axis direction. Further, the CPU 5 is configured to transmit / receive data to / from peripheral devices such as the mounting machine 6 via various I / O ports 57.

  The CPU 5 as the control means operates in response to an operation start command obtained via the input device 41, controls the driving of each drive unit of the inspection device 10, and performs operations detailed later. .

  In the mounting line of this embodiment, the electronic component E is mounted on the board P by the mounting machine 6 as described above, and the mounting board P is conveyed by the conveyor 7 to the carry-in conveyor on the inspection apparatus 10 side.

  On the other hand, as shown in FIG. 8, the inspection apparatus 10 first takes an image necessary for divided imaging from the size of the mounting board P to be inspected and the camera field of view (imaging range) based on data prepared in advance. The number of times, the imaging position, etc. are calculated (step S11). For example, as shown in FIG. 9, when the camera visual field 3A has a size of Lx × Ly, the inspection target area of the mounting board P has a plurality of imaging areas in a grid pattern in the vertical and horizontal directions (XY axis directions) based on the camera visual field 3A Is divided into Pg..., And the number of times of imaging (number of divisions), the imaging position of the camera 3 with respect to the substrate P when imaging each imaging area Pg, and the imaging sequence described in detail later are calculated. At this time, the inspection target area is divided so that the entire inspection target area can be imaged with the smallest number of imaging times, and each imaging position at that time is calculated as an optimal imaging position.

  In the present embodiment, the left-right direction in FIG. 9 is the X-axis direction (row direction), and the up-down direction is the Y-axis direction (column direction). In the example of FIG. The imaging area Pg is divided into 5 rows (y1 to y5) × 6 columns (x1 to x6).

  After the number of times of imaging and the like is calculated, the mounting board P is transported to a predetermined position on the internal conveyor 2 by the carry-in conveyor and the internal conveyor 2, and then the position is fixed (step S12).

  Next, as shown in FIG. 10, the camera 3 is moved relative to the mounting substrate P, and the imaging region Pg including the fiducial mark (position reference mark) Ps on the mounting substrate P is imaged in advance (step). S13). For example, the camera 3 moves to the imaging position corresponding to the imaging region Pg of the first row and first column (x1, y1), and that region is imaged. Similarly, the imaging region of the first row and sixth column (x6, y1) Pg, imaging region Pg of fifth row and first column (x1, y5), imaging region Pg of fifth row and sixth column (x6, y5) are sequentially imaged, and imaging region Pg including fiducial marks Ps at the four corners of the substrate Is imaged. The divided imaging data thus obtained is pasted on the predetermined position memory.

  Subsequently, the camera 3 moves to the next imaging region Pg and is imaged (steps S14 and 15), and the divided imaging data is pasted on the predetermined position memory (step S16). Further, these processes (steps S14, S15, S16) are repeated (step S17: No), and all the divided imaging data are sequentially pasted together without overlapping, and wide area imaging of the entire inspection target area including the substrate P is performed. Data (wide area image) is obtained. When the imaging of all the image areas Pg is completed in this way (step S17: Yes), the imaging / compositing process ends. In this embodiment, component inspection is performed in parallel with the imaging / combination processing. This inspection determination processing will be described in detail later.

  Here, the imaging order will be described. In the present embodiment, as indicated by an arrow 3L in FIG. 11, the imaging region Pg in the first row is imaged in order from the front row (left side) except for the imaging regions Pg at the four corners captured in advance. The imaging region Pg in the second row is imaged sequentially from the rear row (right side). Similarly, the imaging areas in the third and subsequent rows are sequentially imaged for each row. Thus, since the camera 3 meanders with respect to the substrate P and is mainly moved in the X-axis direction, movement in the Y-axis direction, that is, movement on the substrate P side (conveyor 2 side) can be reduced, and the camera 3 side has priority. Can be moved. Therefore, the moving speed can be increased, the inspection efficiency can be improved, the vibration during movement can be reduced, and the inspection accuracy can be improved.

  In the present embodiment, when the first imaging area Pg in each row is imaged, the first imaging area Pg is imaged after the camera 3 is moved in the X-axis direction. For example, when imaging starts from the imaging region Pg of the second column (x2, y1) in the first row, the camera 3 is moved by one imaging region (reverse movement) from the imaging region Pg of the first row, second column (x2, y1). (Position), that is, a position corresponding to the imaging region Pg of the first row and first column (x1, y1). Then, from this state, the camera 3 is moved by one imaging area in the X-axis direction and arranged in the imaging area Pg of the first row and second column (x2, y1), and the imaging area Pg at the position (x2, y1) is set. Take an image. Similarly, when imaging the imaging area Pg of the first image (x6, y2) in the second row, the camera 3 is moved by one imaging area outside the imaging area Pg of the last row (x6, y2) in the second row. It arrange | positions in position T2, and it image | photographs, after moving to the imaging area Pg of the 2nd row last column (x6, y2) from there. Similarly, when imaging the first imaging area Pg in the third row and thereafter, the first imaging area Pg is arranged at positions T3 and T4 moved outward by one imaging area with respect to the first imaging area Pg. In this state, the camera 3 is moved in the X-axis direction and then moved to the first imaging region Pg in each row, and then imaging is performed.

  In this way, when imaging the first imaging region Pg in each row, the first image capturing start condition is adjusted to the same condition as the second and subsequent image capturing start conditions by moving in the X-axis direction in advance. be able to. For this reason, for example, even if the camera 3 is picked up immediately after the movement is stopped, all the image pickup areas Pg can be picked up under the same conditions, and high inspection accuracy can be obtained. Furthermore, since the shooting start conditions are adjusted to be the same, it is advantageous from the viewpoint of backlash of the ball screw 33 that occurs immediately after the camera 3 is moved by the ball screw 33.

  When the first imaging area Pg in each row is imaged by moving in the X-axis direction, the movement amount is at least better than that of one imaging area, and the first imaging is performed after moving a small amount in the X-axis direction. A similar effect can be obtained by imaging the region Pg.

  Further, in the present embodiment, imaging by the camera 3 may be set as an interrupt process, and imaging may be performed with priority when the camera 3 arrives at a predetermined imaging position.

  On the other hand, in this inspection apparatus 10, after photographing the fiducial mark Ps, the electronic component E is inspected in parallel with the above-described imaging / synthesis process.

  That is, as shown in FIG. 13, when the fiducial mark Ps is recognized (step S21: Yes), the substrate position is accurately specified from the position of the fiducial mark Ps. When the substrate position is specified, an ideal center position Eo of each electronic component E on the substrate is calculated based on reference electronic component data (reference component data) prepared in advance as shown in FIG. Based on the center position Eo and the ideal mounting position and angle of each electronic component E, the inspection component region (cutout region) Ea of each component E where each electronic component E exists is calculated (step S22). The inspection part area Ea includes a margin (tolerance and mounting error). Adjacent inspection component areas Ea may overlap each other.

  When the inspection part area Ea is calculated, the imaging / synthesizing process waits until one of the inspection part areas Ea is included in the captured image (a wide-area image being created) (step S23: No). Then, if any of the inspection component areas Ea is included in the captured image as shown in FIG. 15 (step S23: Yes), the inspection component area Ea is the electronic component data to be inspected from the captured image. It is cut out as (inspection part data).

  In the present embodiment, since the cut-out order of the inspection part area Ea is obtained based on the procedure to be imaged, the inspection part areas Ea are sorted in advance from the earliest cut-out order. In step S23, the cut-out order is cut out. Judgment is made in order from the inspection part region Ea with the earlier order.

  Subsequently, the cut-out inspection part data is compared with the reference electronic part data (reference part data) prepared in advance, and the electronic part corresponding to the inspection part data is inspected for missing parts, erroneous part inspection, and misalignment. The mounting state such as inspection and soldering state inspection is inspected (step S24), and the inspection result is output to the display device 42 and the like and stored in the storage device 43.

Thus, the inspection part data is sequentially extracted from the wide area image (wide area imaging data) and sequentially inspected (step S25: No), and when the inspection of all the inspection part data is completed, the inspection of the mounting board P is completed. (Step S25: Yes)
When the inspection part data is cut out from the wide area image, the cut out data is left without being erased. That is, the inspection part data is captured as copy and paste, not so-called cut and paste.

  When all the inspections are completed, the internal conveyor 2 moves forward along the Y-axis direction and is disposed at a position corresponding to the transport line XL. Thereafter, the substrate P is carried out of the housing 1 by the internal conveyor 2 and the carry-out conveyor.

  In this way, the board P on which the electronic component E is mounted by the mounting machine 6 is sequentially conveyed to the inspection apparatus 10 and sequentially inspected.

  On the other hand, in the inspection apparatus 10 of the present embodiment, as will be described in detail below, the position data of the electronic component E is accumulated, and based on this position data, the imaging position by the camera 3 of the inspection apparatus 10 and the mounting machine The mounting position by the six heads 91 is corrected.

  Here, the factors causing the positional shift in the electronic component E of the wide area image are classified into the first to third patterns. The first classification is when the mounting position is shifted due to the axial movement shift of the head 91 of the mounting machine 6, the second classification is when the imaging position is shifted due to the axial movement shift of the camera 3 of the inspection apparatus 10, and the third classification is This is a case where there is a displacement in both the mounting position and the imaging position.

  In the present embodiment, whether or not the image is included in the first classification is determined based on whether or not the component positional deviation amount in each imaging region Pg in the composite image changes at a constant increase / decrease rate with respect to the distance from the reference position. It is done on the basis of. That is, when there is a deviation in the axial movement of the mounting head 91, the positional deviation amount δl of each electronic component E increases or decreases in proportion to the ideal distance from the fiducial mark Ps. Specifically, as shown in FIG. 17, the ideal distance (mm) from the fiducial mark Ps to each of the electronic components E1 to E8 is set to “1.000”, “2.000”, “8.00”. If there is a deviation in the mounting position and there is no deviation in the imaging position, for example, as shown in FIG. 18, the positional deviation amount δl of the first electronic component E1 is “0.003 (= measured distance” 1.003 ”−ideal distance“ 1.000 ”), the positional deviation amount δl of the second electronic component E2 is“ 0.006 ”, the third is“ 0.009 ”,. 024 ". When the relationship between the displacement δl and the ideal distance is shown in a graph, the displacement δl of each component is proportional to the ideal distance from the fiducial mark Ps as shown in FIG. It can be seen that the rate of expansion / contraction changes. Therefore, in this embodiment, as will be described later, it is determined whether there is a deviation in the mounting position based on the increase / decrease rate of the positional deviation amount δl in each imaging region Pg. This is fed back to the machine 6. FIG. 19 is created based on actual measurement values when a specified number of substrates P are inspected, and a line segment la in the graph indicates a least square line passing through each point (hereinafter, FIGS. 24 and 25). The same applies to

  18 and 19 show a case where there is no deviation in the imaging position. However, even if there is a deviation in the imaging position as described later, if there is a deviation in the mounting position, The displacement amount δl of the component changes at a constant increase / decrease rate.

  The determination as to whether or not the image is included in the second category is made based on whether or not the positional deviation amount δl changes for each imaging region Pg. That is, when there is a shift in the axial movement of the camera 3 in the inspection apparatus 10, the edges (tangent sides) of the adjacent imaging regions Pg do not match each other, and for example, as shown in FIG. A fixed gap is formed, and divided images are taken in that state. When the captured images are combined in this state, as shown in FIG. 21, the positional deviation amount δl of the electronic components E1 and E2 in the first (leftmost) imaging region Pg is “0” and the second (middle). The positional deviation amount δl of the electronic components E3 to E5 in the imaging region Pg is “−0.008”, and the positional deviation amount δl of the electronic components E6 to E8 in the third (right end) imaging region Pg is “−0.016. " When the relationship between the positional deviation amount δl and the ideal distance from the fiducial mark Ps is shown in a graph, as shown in FIG. 22, there is a certain amount of step (offset) in the positional deviation amount δl for each imaging region Pg. You can see that it has occurred. Therefore, in this embodiment, as will be described later, it is determined whether there is a deviation in the imaging position based on the positional deviation amount δl for each imaging region Pg, and if there is a deviation, the correction value is set to the inspection apparatus 10 itself. It is something to be fed back to.

  20 to 22 show the case where there is no deviation in the mounting position. However, even if there is a deviation in the mounting position as will be described later, if there is a deviation in the imaging position, the position for each imaging region Pg. The deviation amount δl changes by a predetermined amount.

  The third classification is a case where both of the first and second classifications are included, and the component positional deviation amount δl in each imaging region Pg changes at a constant increase / decrease rate, and the component positional deviation for each imaging region Pg. Judgment is made based on whether or not the amount δl has a predetermined amount of offset. That is, when included in the third classification, for example, as shown in FIG. 23, the positional displacement amount δl of the electronic components E1, E2 in the first (leftmost) imaging region Pg is “0.003”, “0.006”, The positional deviation amount δl of the electronic components E3 to E5 in the second (middle) imaging region Pg is “0.001”, “0.004”, “0.007”, and the electrons in the third (right end) imaging region Pg. The positional deviation amount δl of the parts E6 to E8 is “0.002”, “0.005”, and “0.008”. When the relationship between the positional deviation amount δl and the ideal distance from the fiducial mark Ps is shown in a graph, as shown in FIG. 24, the component positional deviation amount δl in each imaging region Pg changes at a constant increase / decrease rate. In addition, it can be seen that the amount of positional deviation changes by a predetermined amount for each imaging region Pg. Therefore, in this embodiment, when included in this third classification, the correction value is fed back to both the mounting machine 6 and the inspection apparatus 10.

  Next, the operation of the correction process in the inspection apparatus 10 of this embodiment will be described. In the following description, correction in the X-axis direction will be described as an example, but in the present embodiment, correction in the Y-axis direction is performed in the same manner as in the X-axis direction.

  First, as shown in FIG. 16, the inspection apparatus 10 inspects the position of each electronic component E on the substrate P in the wide area image (composite image) and stores it as position data (step S31).

  When the position data on a predetermined number (for example, six) of substrates is accumulated (step S32: Yes), the distance from the fiducial mark Ps of each electronic component E is calculated based on the accumulated position data. The actually measured distance is compared with an ideal distance programmed in advance, and a positional deviation amount δl of each electronic component E is calculated (step S33).

  When the amount of positional deviation δl is very small and correction of the mounting position and the imaging position is not necessary, the correction process ends (No at Step S34).

  If correction is necessary (step S34: Yes), the component displacement amount δl is totalized for each imaging region Pg, and the displacement amount δl is plotted on the vertical axis as shown in FIG. 19, FIG. 22, and FIG. A graph is created with the horizontal axis representing the ideal distance from the char mark Ps to the part. Further, a least square line la passing through each point is created for each imaging region Pg from the graph, and the slope (increase / decrease rate) of the line segment la is obtained (step S35).

  Subsequently, it is determined whether or not the positional deviation amount δl changes in each imaging region Pg at a constant increase / decrease rate, that is, whether or not the line segment la in each imaging region Pg has an inclination (step S36). ). For example, as shown in FIGS. 19 and 24, when the line segment la in each imaging region Pg has an inclination, it is determined to be included in the first classification, and a correction value is calculated from the increase / decrease rate of the positional deviation amount δl. The correction value is fed back to the mounting machine 6, and the movement amount (mounting position) of the head 41 is corrected (step S37). Note that the rate of increase / decrease of the positional deviation amount δl of each imaging region Pg (the slope of the line segment la of each imaging region Pg) is equal.

  Next, after the correction value is fed back to the mounting machine 6 or when the positional deviation amount δl in each imaging area Pg has not changed (step S36: No), the positional deviation at the boundary between the adjacent imaging areas Pg. A step amount (offset amount) of the amount δl is obtained (step S38).

  Subsequently, it is determined whether or not the amount of positional deviation for each imaging region Pg changes stepwise, that is, whether or not there is an offset (step S39). For example, as shown in FIGS. 22 and 24, when there is an offset, it is determined to be included in the second classification. Then, a correction value is calculated from the offset amount, and the correction value is fed back to the inspection apparatus 10 itself, so that the movement amount (imaging position) of the camera 3 is corrected (step S40). The offset amount for each imaging region Pg is equal.

  Subsequently, after the feedback of the correction value is completed or when there is no offset (step S39: No), the correction process in the inspection apparatus is completed.

  As described above, in the present embodiment, the amount of positional deviation in the X-axis and Y-axis directions is obtained, and bidirectional correction is performed.

  As described above, in the present embodiment, the positional deviation amount δl of each electronic component is calculated from the composite image obtained by synthesizing the divided imaging data, and the positional deviation amount δl is totalized for each imaging region Pg. Since the image pickup position of the camera 3 is corrected based on the positional deviation amount δl for each image pickup region Pg, the high-precision wide-area image is obtained by connecting the divided image pickup data with good position accuracy without overlapping. be able to. Therefore, it is possible to inspect with high accuracy based on this high-accuracy wide-area image. Furthermore, the part inspection range can be narrowed down easily and accurately based on this high-accuracy wide-area image, the inspection time can be shortened, and the inspection efficiency can be improved.

  Further, since the mounting position by the mounting machine 6 is corrected based on the positional deviation amount δl in each imaging region Pg, the positional accuracy of the mounting machine 3 can be maintained at a high level.

  In the present embodiment, correction data (position data) is acquired from the mounting board P under inspection and the imaging position and the mounting position are corrected. Therefore, the effective correction data immediately before is used. Can be corrected accurately. For example, conditions such as indoor temperature and humidity vary depending on the time and day, and the correction value also changes depending on the conditions. In this embodiment, however, the correction is based on the data acquired immediately before, so in time series Even if the condition changes, it can be accurately corrected according to each condition.

  In particular, in the present embodiment, it is possible to effectively cope with expansion and contraction due to a temperature change of a ball screw as a moving means of the camera 3 and the mounting head 91. That is, in order to cope with the temperature expansion and contraction of the ball screw, for example, the expansion rate of the ball screw is measured in advance every operating time, the method of correcting the movement amount according to the operating time, the temperature of the ball screw portion is measured, There is a method of obtaining and correcting the expansion ratio of the ball screw from the temperature change. However, these methods lack accuracy and cannot obtain a particularly accurate correction value when conditions are different. On the other hand, in the present embodiment, the correction value is obtained using the immediately measured data, so that it is possible to effectively cope with the temperature expansion and contraction of the ball screw.

  As described above, the correction method according to the present embodiment may be used in combination with a method for determining and correcting the expansion ratio of the ball screw from the temperature change. In this case, when the correction values derived from the two correction methods coincide with each other, a highly reliable correction value can be obtained. Therefore, a method of correcting with this highly reliable correction value is also employed. can do.

  In this embodiment, every time a predetermined number of substrates P are processed, the imaging position and the mounting position are corrected. Therefore, the imaging position deviation and the mounting position deviation are corrected one by one within a tolerance range. It is possible to prevent the occurrence of harmful shifts due to the accumulation of slight shifts.

  Further, in the inspection apparatus 10 of the present embodiment, inspection part data is cut out from the wide-area imaging data and inspected, so the number of times of imaging for the substrate P is specified regardless of the number of electronic parts E to be mounted. For this reason, even if the number of electronic parts E increases, the number of times of imaging can be reduced, inspection time can be greatly shortened, and inspection efficiency can be improved.

  In particular, in the present embodiment, when a large number of electronic components E are mounted on the substrate P with high density, inspection can be performed more efficiently. For example, when a divided image is taken for each electronic component and the inspection component data is captured from the divided image data as in the conventional inspection method, a lot of unnecessary data other than the inspection component data is included in the divided image data. Unnecessary data needs to be deleted. In addition, in the conventional inspection method, when adjacent inspection component areas on the substrate overlap, the overlapping portions are imaged redundantly, and the imaging efficiency is also reduced.

  On the other hand, in the present embodiment, when the electronic components E are mounted at a high density, since the electronic components E exist without any gap in the wide area imaging data, almost all of the wide area imaging data can be used without waste and unnecessary data. Can be reduced and inspection can be performed efficiently. Further, in this embodiment, since the inspection part area is extracted from the wide-area imaging data obtained by joining the divided imaging data, the overlapping part of the adjacent inspection part areas is only used by duplicating the imaging data of that part. Therefore, it is not necessary to perform overlapping imaging, and the imaging efficiency can be significantly improved.

  In the present embodiment, the divided parts that have been picked up separately are pasted together, and the inspection part data that can be cut out is cut out and inspected from the wide area image being created. Therefore, in parallel with the image pickup / combination process. In addition, component inspection can be performed as background processing, and inspection efficiency can be further improved. Further, in extracting inspection part data from a wide area image, positioning using fiducial marks Ps can improve the cutout accuracy, and as a result, the mounting state inspection accuracy can be improved.

  Further, in the present embodiment, adjacent imaging regions Pg are imaged without overlapping, and adjacent divided imaging data are connected without overlapping to create wide-area imaging data. In addition to being able to improve, the data processing of the overlap portion is not necessary, and the inspection efficiency can be further improved.

  In the present embodiment, when the fiducial mark Ps is imaged in advance, only the imaging region including the fiducial mark Ps is imaged. However, the present invention is not limited to this, As shown in FIG. 25, all of the imaging regions Pg in each row (the first row and the fifth row in FIG. 25) including the fiducial mark Ps may be imaged in advance. In this case, movement of the camera 3 in the Y-axis direction (movement by the conveyor 2) during imaging can be reduced, and imaging processing can be performed more efficiently.

  When the fiducial mark Ps is located at the boundary between the two imaging regions Pg and is located across the two imaging regions Pg, the two imaging regions Pg and the imaging regions Pg of each row including the region are included. May be taken in advance.

  Further, when imaging the fiducial mark Ps in advance, one or more of the fiducial marks Ps among the plurality of fiducial marks Ps is imaged in advance, and the remaining fiducial marks Ps are captured. May be taken later.

  However, in the present invention, it is not always necessary to image the fiducial mark first, and the present invention can also be applied to a substrate to which a position reference mark such as a fiducial mark is not provided.

  Further, in the above-described embodiment, the case where the entire area of the mounting substrate P is imaged has been described. However, the present invention is not limited to this. In the present invention, an image that does not require inspection may be skipped and imaged. . For example, as shown in FIG. 26, only the area Pg including the electronic component E and the fiducial mark Ps on the mounting board P may be divided and the remaining areas may not be imaged. At this time, as many electronic components as possible are included in each imaging region Pg, and the imaging position, the imaging frequency, and the imaging order are calculated so that imaging can be performed with the smallest imaging frequency.

  In the above-described embodiment, when the divided imaging is performed, the adjacent imaging regions Pg are imaged without overlapping. However, the present invention is not limited to this, and in the present invention, the adjacent imaging regions Pg are overlapped. You may make it image.

  In the above embodiment, the camera is configured to move only in the X-axis direction. However, the present invention is not limited to this, and in the present invention, the camera is configured to move together in the X-axis and Y-axis directions. The substrate may be fixed at the time of the imaging process, and the camera may be moved in the XY axis direction, and the substrate side may be moved together in the X and Y axis directions. May be fixed and the substrate side may be moved in the XY-axis direction.

It is a block diagram which shows the mounting line concerning one Embodiment of this invention. It is a front view of the inspection device applied to one embodiment of this invention. It is side surface sectional drawing which shows the inspection apparatus of embodiment. It is a top view which shows roughly the internal structure in the inspection apparatus of embodiment. It is a front view which shows roughly the internal structure in the inspection apparatus of embodiment. It is a side view which shows roughly the internal structure in the inspection apparatus of embodiment. It is a block diagram which shows the main control system of the inspection apparatus of embodiment. It is a flowchart which shows the imaging / combination process in the test | inspection apparatus of embodiment. It is a top view which divides | segments and shows a mounting board | substrate in an imaging area in embodiment. It is a top view which shows the prior | preceding imaging area | region of a mounting board in embodiment. It is a top view which shows the imaging sequence of a mounting board in embodiment. It is a flowchart which shows the inspection judgment process in the inspection apparatus of embodiment. It is a top view which shows the electronic component center position of the mounting substrate in embodiment. It is a top view which shows the test | inspection components area | region of a mounting board in embodiment. It is a top view which shows the wide area image in preparation of the mounting board | substrate in embodiment. It is a flowchart which shows the correction | amendment process in the mounting board | substrate of embodiment. It is a top view which shows the ideal synthesized image in embodiment. It is a top view which shows the synthesized image contained in a 1st classification | category in embodiment. It is a graph which shows the relationship between the amount of components position shift and an ideal distance in the 1st classification synthetic image. It is a top view which shows the image contained in a 2nd classification in the embodiment in the state before a synthesis | combination. It is a top view which shows the state after a synthesis | combination in the image contained in the 2nd classification | category in embodiment. It is a graph which shows the relationship between the amount of component position shifts and an ideal distance in the synthetic image of the 2nd classification. It is a top view which shows the synthesized image contained in a 3rd classification | category in embodiment. It is a graph which shows the relationship between the amount of components position shift and an ideal distance in the 3rd classification synthetic image. It is a top view which shows the prior | preceding imaging area | region of the mounting board | substrate in one modification of this invention. It is a top view which shows the imaging area of a mounting board in the other modification of this invention.

Explanation of symbols

3 Camera (imaging means)
6 Mounting Machine 10 Inspection Device 20 Y Axis Moving Means 30 X Axis Moving Means E, E1 to E8 Electronic Component P Mounting Board Pg Imaging Area Ps Fiducial Mark (Position Reference Mark)

Claims (8)

A method of imaging a mounting board on which electronic components are mounted by an imaging means,
An imaging step of dividing the mounting substrate into a plurality of imaging areas and sequentially moving the imaging means to each imaging area to obtain a plurality of divided imaging data;
A combining step of connecting the plurality of divided imaging data to obtain combined imaging data;
A mounting board imaging method, comprising: a correction step of correcting an imaging position of the imaging means with respect to the imaging area based on a positional deviation amount for each imaging area in the composite imaging data.   2. The mounting substrate imaging method according to claim 1, wherein in the combining step, the plurality of divided imaging data are connected without overlapping. In the imaging step, an imaging region including a position reference mark given to the mounting substrate is imaged,
In the correction step, position data of a plurality of electronic components in the composite imaging data is obtained with reference to the position reference mark, and the position data is compared with position data of a reference electronic component prepared in advance. 3. The positional deviation amount of each electronic component is calculated, the positional deviation amount of each electronic component is totaled for each imaging region, and the positional deviation amount for each imaging region is calculated. The mounting substrate imaging method described.   The correction value for correcting the mounting position by the mounting machine is calculated in the correction step based on a positional deviation amount in each imaging area in the composite imaging data. The mounting board imaging method described in 1. A mounting board inspection method for inspecting a mounting board on which electronic components are mounted,
An electronic component corresponding to the inspection component data based on the inspection component data, partially extracted from the combined imaging data obtained by the mounting substrate imaging method according to claim 1. A method for inspecting a mounting board, characterized by determining whether the product is good or bad. A mounting board inspection apparatus for inspecting a mounting board on which electronic components are mounted,
Moving means for moving the imaging means relative to the mounting substrate in the X-axis direction and the Y-axis direction parallel to the imaging surface;
6. A mounting board inspection apparatus comprising: control means for controlling driving of the imaging means and the moving means to execute the inspection method according to claim 5. A mounting line comprising a mounting machine for mounting electronic components on a board, and an inspection device for inspecting a board on which the electronic parts are mounted by the mounting machine,
A mounting line, wherein the inspection device is configured by the mounting substrate inspection device according to claim 6.   The mounting line according to claim 7, wherein, in the correction step, a mounting position by a mounting machine is corrected based on a positional deviation amount in each imaging region in the composite imaging data.