JP6674705B2 - Image recognition device - Google Patents

Description

  The present invention relates to an image recognition apparatus that captures a side image of a component sucked by a suction nozzle of a component mounting machine with a camera, processes the side image, and measures a height dimension (thickness dimension) of the component. .

  As described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2008-124293), a side image of a component sucked at the lower end of a suction nozzle is captured by a camera and image processing is performed to determine whether the suction attitude of the component is good or bad. In some cases, the presence or absence of a suction component is determined. Specifically, in a state where the reference jig is held by the nozzle holder holding the suction nozzle instead of the suction nozzle, a side image of the reference jig is taken as a “reference image” and image processing is performed. Then, after determining the height position of the reference jig as the reference height position, the reference jig is removed from the nozzle holder and replaced with a suction nozzle, and a side image of the component suctioned by the suction nozzle is captured and imaged. By processing, the height position of the lower end (lowest point) of the part is obtained, the height difference (difference) between the reference height position and the height position of the lower end of the part is calculated, and based on the height difference To measure the height of the part.

JP 2008-124293 A JP 2013-251398 A

  By the way, as shown in FIGS. 3B and 3C, the suction nozzle (13) may be inclined due to the inclination of the mounting head (nozzle holder) or the like. Since the component is also inclined, the height position of the lower end (lowest point) of the component is lowered, and the measured value of the height dimension of the component becomes larger than the actual dimension. As a result, as shown in FIG. 3A, even if the component is determined to be normal (OK) if the suction nozzle is not tilted, as shown in FIG. There is a possibility that it may be out of the acceptable range and erroneously determined as abnormal (NG). Also, if the suction nozzle is inclined, as shown in FIG. 3C, the height position of the lower end (lowest point) of the component also changes due to the shift of the component suction position. Measured values also vary depending on the shift of the component suction position. Therefore, the measured value of the height dimension of the component measured from the side surface image of the component suctioned by the suction nozzle fluctuates due to both the inclination of the suction nozzle 13 and the shift of the component suction position, which is a cause of erroneously determining normal / abnormal. Become.

  Japanese Patent Application Laid-Open No. 2013-251398 discloses a suction nozzle in which a nozzle tip is imaged from below with a camera in order to measure the displacement of the nozzle tip (component mounting displacement). A technique for measuring the inclination angle of a component is described, but a method for measuring a height dimension of the component from a side image of the component sucked by the suction nozzle is not described.

  Therefore, the problem to be solved by the present invention is to accurately measure the height dimension of a component suctioned from a suction nozzle from a side image of the component without being affected by the inclination of the suction nozzle or a shift of the component suction position. An object of the present invention is to provide an image recognition device.

In order to solve the above problem, the invention according to claim 1 captures a side image of a component sucked by a suction nozzle of a component mounting machine with a camera, processes the side image, and measures a height dimension of the component. an image recognition apparatus for a camera installation angle adjusting an inclination angle measuring means for measuring the inclination-out angle of the suction nozzle, the installation angle of the camera in accordance with the tilt angle of the suction nozzle measured by the inclination angle measuring means This is a configuration including an adjusting unit . In this arrangement, for adjusting the installation angle of the camera in accordance with the inclination-out angle of the suction nozzle measured by the inclination angle measuring means, without being affected by the deviation of the inclination and the component suction position of the suction nozzle, the suction in the suction nozzle The height dimension of the component can be accurately measured from the side image of the component.

FIG. 1 is a front view showing a configuration of a mounting head of a component mounting machine and a peripheral portion thereof according to a first embodiment which is a reference example related to the present invention. FIG. 2 is a block diagram showing a configuration of a control system of the component mounter. FIG. 3A is a diagram showing a relationship between the side image of the component when the suction nozzle is not inclined and the acceptable range, and FIG. 3B is a diagram showing the side image of the component and the acceptable range when the suction nozzle is inclined. FIG. 3C is a diagram showing the relationship between the side image of the component and the acceptable range when both the inclination of the suction nozzle and the deviation of the component suction position are present. FIGS. 4A to 4C are diagrams illustrating a method for measuring the height of a component according to the first embodiment. FIG. 5 is a flowchart showing the flow of processing in the first half of the part height measurement program according to the first embodiment. FIG. 6 is a flowchart illustrating the flow of processing in the second half of the part height measurement program according to the first embodiment. FIG. 7 is a view for explaining a component height measurement method according to a second embodiment which is a reference example related to the present invention . FIG. 8 is a flowchart showing the flow of processing in the second half of the part height measurement program according to the second embodiment.

  Hereinafter, three embodiments 1 to 3 that embody the embodiments for carrying out the present invention will be described.

First Embodiment A reference example related to the present invention will be described with reference to FIGS. 1 to 5.
First, the configuration of the rotary mounting head 11 of the component mounting machine will be described with reference to FIG.
A plurality of nozzle holders 12 are supported on the rotary mounting head 11 at predetermined intervals in the circumferential direction so as to be able to move up and down. It is movably engaged and held. In FIG. 1, only two nozzle holders 12 (suction nozzles 13) are shown, and illustration of other nozzle holders 12 (suction nozzles 13) is omitted.

  A head moving mechanism 15 that moves the mounting head 11 in the XY directions includes an X-axis slide 17 that slides in the X-axis direction (a direction perpendicular to the plane of FIG. 1), which is the substrate transfer direction, with an X-axis ball screw 16. The XY robot includes a Y-axis slide 18 that moves in a Y-axis direction orthogonal to the X-axis direction by a ball screw (not shown). The X-axis slide 17 is supported so as to be slidable in the X-axis direction along an X-axis guide rail 19 provided on the Y-axis slide 18, and the Y-axis slide 18 is a Y-axis guide provided on the component mounter body side. It is slidably supported in the Y-axis direction along a rail (not shown).

  The support frame 21 of the mounting head 11 is detachably attached to the X-axis slide 17. The mounting head 11 is fitted to the lower end of an R-axis 22 (also referred to as an index axis) extending in the vertical direction, and the upper side of the R-axis 22 is rotatably supported by the support frame 21. The R-axis 22 is driven to rotate by an R-axis motor 23 fixed to the support frame 21 side. The rotation of the R-axis 22 rotates the mounting head 11 about the R-axis 22, so that the plurality of nozzle holders 12 supported by the mounting head 11 are integrally formed with the plurality of suction nozzles 13. The mounting head 11 is turned in the circumferential direction. An R-axis drive mechanism 24 includes the R-axis motor 23, the R-axis 22, and the like.

  Upper and lower two-stage Q-axis gears 28 and 29 of a Q-axis drive mechanism 27 are rotatably inserted through the R-axis 22, and the lower Q-axis gear 29 has a gear fitted to the upper end of each nozzle holder 12. 30 are engaged. A gear 33 connected to a Q-axis motor 31 fixed to the support frame 21 meshes with the upper Q-axis gear 28, and the rotation of the gear 33 of the Q-axis motor 31 integrally forms the Q-axis gears 28 and 29. By rotating, each gear 30 meshing with the lower Q-axis gear 29 rotates, and each nozzle holder 12 rotates around the axis of each nozzle holder 12 (Q-axis). The direction (angle) of each component sucked by each suction nozzle 13 held at the position is corrected. Note that the Q axis is sometimes called the θ axis.

  Further, on the side of the R-axis drive mechanism 24, a Z-axis drive mechanism 37 for individually lowering the nozzle holder 12 is provided. The holders 12 are individually lowered, and the suction nozzles 13 held by the nozzle holders 12 are lowered. The Z-axis drive mechanism 37 may be arranged at only one place around the mounting head 11, or may be arranged at two or more places.

  The Z-axis drive mechanism 37 rotates the Z-axis ball screw 38 rotatably supported on the support frame 21 side by the Z-axis motor 39 to move the Z-axis slide 40 in the up and down direction. The engagement piece 42 of the Z-axis slide 40 is engaged (contacts) with the flange 41 from above to move the nozzle holder 12 up and down. In this case, each nozzle holder 12 is urged upward by a spring 43 attached to each nozzle holder 12 so that the upper end flange 41 of each nozzle holder 12 engages with the engagement piece 42 of the Z-axis slide 40 from below. The nozzle holder 12 is held in such a state that the nozzle holder 12 is raised by the pushing force of the spring 43 as the engagement piece 42 of the Z-axis slide 40 is raised.

  On the other hand, on the side of the mounting head 11, an image pickup device 46 for picking up an image of the component sucked by the suction nozzle 13 from the side is arranged. The imaging device 46 includes a camera 48 fixed to the support frame 21 via a holder 47, an illumination light source 49, and the like. The height position of the camera 48 is such that the tip (lower end) of the suction nozzle 13 is within the visual field of the camera 48 when the suction nozzle 13 rises to the upper limit position (standby position) of the elevating range after the component suction operation and stands by. The setting is made so that a side image around the tip of the suction nozzle 13 including the component sucked in (1) can be captured.

  Correspondingly, a cylindrical light which reflects illumination light from an illumination light source 49 when a component adsorbed by the adsorption nozzle 13 is imaged by a camera 48 from a side thereof is provided at a central portion on a lower surface side of the mounting head 11. A reflection plate 51 is provided. The height position of the lower end of the light reflection plate 51 is set to a height position at which the light reflection plate 51 does not interfere with components and the like when the suction nozzle 13 is lowered to suck the components.

  The control device 55 (see FIG. 2) of the component mounter controls the operations of the R-axis drive mechanism 24, the Q-axis drive mechanism 27, the Z-axis drive mechanism 37, and the head moving mechanism 15, and the component supply device 56 (see FIG. 2). (See FIG. 1) is sucked by the suction nozzle 13 and mounted on the circuit board.

  Further, the control device 55 of the component mounter also functions as an image recognition device that processes a side image around the tip of the suction nozzle 13 captured by the camera 48 and measures the height dimension of the component. The height of the component sucked by the suction nozzle 13 is determined to be normal / abnormal (for example, the component suction attitude is abnormal, the component type is wrong, etc.), and when it is determined that the component is abnormal, the component is returned to a predetermined disposal place. They are discarded or collected on a collection conveyor (not shown).

  By the way, the suction nozzle 13 may be inclined due to the inclination of the mounting head 11 (nozzle holder 12) or the like. However, as shown in FIG. Due to the inclination, the height position of the lower end (lowest point) of the part is lowered, and the measured value of the height dimension of the part becomes larger than the actual dimension. As a result, as shown in FIG. 3A, even if the component is determined to be normal (OK) if the suction nozzle 13 is not tilted, as shown in FIG. May be out of the acceptable range and erroneously determined as abnormal (NG). Further, if the suction nozzle 13 is inclined, as shown in FIG. 3C, the height position of the lower end (lowest point) of the component also changes due to the shift of the component suction position. The measured value of the dimension also fluctuates due to a shift in the component suction position. Accordingly, the measured value of the height dimension of the component measured from the side image of the component suctioned by the suction nozzle 13 fluctuates due to both the inclination of the suction nozzle 13 and the shift of the component suction position, and causes the erroneous determination of normal / abnormal. Becomes

Therefore, in the first embodiment, the control device 55 of the component mounter executes the component height measurement program in FIGS. 5 and 6 to measure the tilt angle of the tip surface of the suction nozzle 13. In addition to functioning as a means, it also functions as a tilt correction unit that corrects the tilt angle of the side image of the component according to the measured tilt angle of the tip surface of the suction nozzle 13, and further, based on the side image of the component whose tilt has been corrected. It also functions as a component height measurement unit that measures the height of the component. Hereinafter, the processing content of the component height measurement program of FIG. 5 will be described. In the following description, “the inclination angle of the tip surface of the suction nozzle 13” is simply described as “the inclination angle of the suction nozzle 13”.

  5 and 6 are repeatedly executed at predetermined intervals by the control device 55 of the component mounter. When the program is started, first, in step 101, the process waits until the tip of the suction nozzle 13 before picking up the component to be imaged reaches the imaging position in the field of view of the camera 48, and When the portion reaches the imaging position in the field of view of the camera 48, the process proceeds to step 102, where the camera 48 captures a side image including the tip portion of the suction nozzle 13.

Thereafter, the process proceeds to step 103, where the side surface image including the tip of the suction nozzle 13 is subjected to image processing to recognize the lowest point (X1, Z1) and the highest point (X2, Z2) of the tip of the suction nozzle 13. I do. Then, in the next step 104, the inclination angle θ of the suction nozzle 13 is calculated from the following relation from the positional relationship between the lowermost point (X1, Z1) and the uppermost point (X2, Z2) of the tip surface of the suction nozzle 13.
θ = tan ^-1 {(Z2-Z1) / (X2-X1)}

  Thereafter, the process proceeds to step 105, where the component is sucked to the tip of the suction nozzle 13. Thereafter, the process proceeds to step 106 and waits until the tip of the suction nozzle 13 after picking up the component to be imaged reaches the imaging position in the field of view of the camera 48. At the point of time when the imaging position is reached, the process proceeds to step 107, and the camera 48 captures a side image of the component sucked at the tip of the suction nozzle 13. At this time, as shown in FIGS. 4A and 4B, the positions of the lowermost point (X1, Z1) and the uppermost point (X2, Z2) of the tip surface of the suction nozzle 13 are determined by the above-described step 102. The lowermost point (X1, Z1) and the uppermost point (X2, Z2) of the tip surface of the suction nozzle 13 imaged before the suction are at the same position.

  Thereafter, the process proceeds to step 108 in FIG. 6, in which the side image of the component is rotated by the inclination angle θ of the suction nozzle 13 around the lowermost point (X1, Z1) of the suction nozzle 13 so as to rotate the side image of the component. Correct the tilt. By this inclination correction, as shown in FIG. 4C, the inclination of the suction nozzle 13 and the inclination of the components in the side image are eliminated.

  Thereafter, the process proceeds to step 109, where the lowest point (X1, Z1) of the suction nozzle 13 is set as a reference height position with respect to the side image of the component whose inclination has been corrected, and the lowest point of the component suctioned by the suction nozzle 13 is set. A pass range corresponding to the allowable error range of the (lower) height position is set. Thereafter, the process proceeds to step 110, where the lowest point (lower end) of the component is recognized, and in the next step 111, it is determined whether or not the height position of the lowest point of the component is within the acceptable range. As a result, if it is determined that the height position of the lowest point of the component falls within the acceptable range, the process proceeds to step 112, where it is determined that the component is normal, and the program is terminated. On the other hand, if it is determined in step 111 that the height position of the lowest point of the component is not within the acceptable range, it is determined that the component is abnormal (for example, an abnormal component suction attitude, an incorrect component type, etc.). To end this program.

  Note that the measurement of the inclination angle θ of the suction nozzle 13 may be performed each time before the inclination correction of the side image of the component, but after the inclination angle θ of the suction nozzle 13 is measured first, Instead of measuring the inclination angle θ of the suction nozzle 13 before correcting the inclination of the side image of the component, the inclination of the side image of the component is corrected using the inclination angle θ of the suction nozzle 13 measured first. You may do it.

  According to the first embodiment described above, the inclination angle of the suction nozzle 13 is measured by processing the side image including the distal end portion of the suction nozzle 13 captured by the camera 48, and the inclination angle of the suction nozzle 13 is measured according to the inclination angle. Since the inclination angle of the side image of the component is corrected by the adjustment, the height of the component is determined from the side image of the component sucked by the suction nozzle 13 without being affected by the inclination of the suction nozzle 13 or the shift of the component suction position. The dimension can be measured with high accuracy.

  Further, in the first embodiment, a side image including the tip portion of the suction nozzle 13 is captured by the camera 48, and the side image is processed to measure the inclination angle of the suction nozzle 13. There is an advantage that the inclination angle of the suction nozzle 13 can be measured by image processing using a camera 48 that captures a side image of the component that has been sucked.

  Moreover, in the first embodiment, the lowest point and the highest point of the tip surface of the suction nozzle 13 are recognized from the side image including the tip portion of the suction nozzle 13, and the positional relationship between the lowest point and the highest point is determined. Since the inclination angle of the suction nozzle is calculated based on the suction nozzle 13, even if only the vicinity of the tip of the suction nozzle 13 is within the field of view of the camera 48 that captures a side image of the component suctioned by the suction nozzle 13, The inclination angle of the suction nozzle 13 can be calculated from the side image including the tip portion of the suction nozzle 13 captured at 48.

  Furthermore, in the first embodiment, when a side image captured in a state where a component is sucked to the suction nozzle 13 is used, it is difficult to distinguish the lowest point and the highest point of the tip surface of the suction nozzle 13 from the component. Considering that there is a case, the lowermost point and the uppermost point of the tip surface of the suction nozzle 13 are recognized using the side image captured in a state where the component is not sucked. The lowest point and the highest point can be easily and accurately recognized, and the inclination angle of the suction nozzle 13 can be accurately measured. However, if the imaging environment allows the lowermost point and the uppermost point of the distal end surface of the suction nozzle 13 to be distinguished from the component from the side image captured while the component is being sucked by the suction nozzle 13, the component is attached to the suction nozzle 13. The inclination angle of the suction nozzle 13 may be measured by using a side image captured in the suction state.

  In the first embodiment, the tilt of the side image of the component is corrected by rotating the side image of the component by the tilt angle of the suction nozzle 13 around the lowermost point of the tip end surface of the suction nozzle 13. Therefore, the position of the lowest point on the tip surface of the suction nozzle 13 does not change before and after the inclination correction. For this reason, as in the first embodiment, when measuring the height dimension of the component with the lowest point of the tip end surface of the suction nozzle 13 as the reference height position, the lowermost point of the component suctioned by the suction nozzle 13 is measured. By simply recognizing the height position, the height dimension of the component can be easily measured.

  However, the rotation center of the inclination correction is not limited to the lowermost point of the tip end surface of the suction nozzle 13, and may be, for example, the origin of the coordinate system of the side image or the center point of the side image (the center point of the visual field of the camera 48). The rotation may be adjusted to correct the tilt.

  In the first embodiment, a pass range corresponding to the allowable error range of the height position of the lowest point (lower end) of the component is set for the side image of the component whose inclination has been corrected, and the lower limit of the lower end of the component is set. Since it is determined whether or not the height position falls within the acceptable range, the height dimension of the component suctioned by the suction nozzle 13 is normal / abnormal (for example, the component suction attitude is abnormal, the component type is incorrect, etc.). ) Can be easily determined.

However, in the present invention, the height dimension of the component may be calculated by the following equation using the height position of the lowest point (lower end) of the component recognized from the side image of the component whose inclination has been corrected.
[Part height dimensions]
= [Height position of lowest point of suction nozzle 13]-[height position of lowest point of component]

  Further, the present invention is not limited to a configuration in which the side surface image captured by the camera 48 is processed to measure the inclination angle of the suction nozzle 13. For example, the suction nozzle 13 may be determined based on measurement data at the time of calibration before the start of production. May be calculated. When measuring the inclination angle of the nozzle holder 12 (mounting head 11) holding the suction nozzle 13 and the amount of positional deviation of the tip of the suction nozzle 13 during calibration before the start of production, the inclination of the suction nozzle 13 is determined from the measurement data. The angle may be calculated. Alternatively, using a camera that captures the component sucked by the suction nozzle 13 from below, the tip of the suction nozzle 13 is imaged by the camera at the ascending position and the descending position of the suction nozzle 13, and the tip of the suction nozzle 13 is Recognizing the position, measuring the amount of displacement of the tip of the suction nozzle 13 between the rising position and the lowering position of the suction nozzle 13, and detecting the height difference between the rising position and the lowering position of the suction nozzle 13 and the suction. The inclination angle of the suction nozzle 13 (the inclination angle of the nozzle holder 12) may be calculated from the positional deviation amount of the tip of the nozzle 13.

Next, a second embodiment, which is a reference example related to the present invention , will be described with reference to FIGS. However, portions that are substantially the same as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified, and different portions are mainly described.

  In the first embodiment, the inclination angle of the side image of the component is corrected in accordance with the measured inclination angle of the suction nozzle 13. In the second embodiment of the present invention, as illustrated in FIG. Instead of correcting the inclination, the horizontal and vertical coordinate axes of the side surface image are corrected, and the height of the component is measured along the corrected vertical coordinate axis.

  In the second embodiment, the control device 55 of the component mounter measures the inclination angle θ of the suction nozzle 13 by the same process as that of the first half of the component height measurement program of FIG. 5 described in the first embodiment. After the component is sucked to the tip of the suction nozzle 13 and a side image of the component is captured by the camera 48, the measurement is performed by executing the latter half of the component height measurement program shown in FIG. In addition to functioning as tilt correction means for correcting the horizontal and vertical coordinate axes of the side surface image of the component in accordance with the tilt angle θ of the suction nozzle 13, along the vertical coordinate axis whose tilt has been corrected based on the side image of the component. Also functions as a component height dimension measuring means for measuring the height dimension of the component.

  Hereinafter, the processing content of the component height measurement program of FIG. 8 will be described. After performing the same processing as that of the first half of the component height measurement program of FIG. 5 described in the first embodiment, the process proceeds to step 201, where the horizontal and vertical coordinate axes of the side image of the component are set by the suction nozzle 13. The tilt is corrected by the tilt angle θ, and the vertical coordinate axis is set parallel to the central axis of the suction nozzle 13.

Thereafter, the process proceeds to step 202, in which a line in an acceptable range corresponding to an allowable error range of the height position of the lowermost point (lower end) of the component with respect to the side surface image of the component is tilt-corrected in the horizontal coordinate axis. The angle is set in accordance with the angle θ. Thereafter, the process proceeds to step 203, where the lowest point (lower end) of the component is recognized, and in the next step 204, it is determined whether or not the height position of the lowest point of the component is within the acceptable range. As a result, if it is determined that the height position of the lowest point of the component falls within the acceptable range, the process proceeds to step 205, where it is determined that the component is normal, and the program ends. On the other hand, if it is determined in step 204 that the height position of the lowest point of the component is not within the acceptable range, it is determined that the component is abnormal (for example, an abnormal component suction attitude, an incorrect component type, etc.). To end this program.
Also in the second embodiment described above, the same effect as in the first embodiment can be obtained.

  In the first and second embodiments, the inclination of the side image or the coordinate axis of the component is corrected. However, in the third embodiment of the present invention, the camera 48 is adjusted in accordance with the inclination angle of the suction nozzle 13 measured by the inclination angle measuring means. And a camera installation angle adjusting means for adjusting the installation angle of the camera. In this case, the camera installation angle adjusting means may be configured to adjust the installation angle of the camera 48 by an operator's operation, or may be provided with a drive source such as a motor and adjust the camera 48 in accordance with the inclination angle of the suction nozzle 13. May be configured to automatically adjust the installation angle of. Note that the inclination angle of the suction nozzle 13 may be measured by the same method as that in the first embodiment.

  If the installation angle of the camera 48 is adjusted in accordance with the inclination angle of the suction nozzle 13 as in the third embodiment, the same effect can be obtained as in the case of correcting the inclination of the side image of the component or the coordinate axis. .

  The present invention is not limited to the first to third embodiments. For example, the configuration of the component mounter or the mounting head 11 may be changed, or the method of measuring the inclination angle of the suction nozzle 13 may be changed. It goes without saying that various changes can be made without departing from the scope of the invention.

  DESCRIPTION OF SYMBOLS 11 ... Mounting head, 12 ... Nozzle holder, 13 ... Suction nozzle, 15 ... Head moving mechanism, 37 ... Z-axis drive mechanism, 48 ... Camera, 49 ... Illumination light source, 55 ... Control device (tilt angle measuring means, tilt correcting means) , Means for measuring the height of parts)

Claims (1)

In an image recognition device that captures a side image of a component sucked by a suction nozzle of a component mounter with a camera and processes the side image to measure a height dimension of the component,
Tilt angle measuring means for measuring the tilt angle of the suction nozzle,
An image recognition device, comprising: a camera installation angle adjustment unit that adjusts an installation angle of the camera in accordance with the inclination angle of the suction nozzle measured by the inclination angle measurement unit.

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