Mounting machine, substrate height measurement position determination device, and substrate height measurement position determination method

Abstract

A mounting machine according to the present invention has a function for automatically determining the positions of measurement points for measuring the substrate height of a substrate on which a component is mounted. The mounting machine comprises an imaging device, an inspection device, and a determination device. The imaging device images, on the basis of a preset imaging condition, temporary measurement points disposed at temporary positions on the substrate. The inspection device inspects the temporary measurement points and the surrounding situation thereof by using a captured image of each of the temporary measurement points, and determines the suitability of the positions of the temporary measurement points. The determination device determines the positions as measurement points when the inspection device has determined that the positions of the temporary measurement points are suitable, and does not determine the positions as the positions of the measurement points when the inspection device has determined that the positions of the temporary measurement points are not suitable.

Description

Mounting machine, board height measurement position determining device, and board height measurement position determining method

[0001] The technology disclosed in this specification relates to a mounting machine, and more particularly to a technology for measuring the height of a board on which components are mounted by the mounting machine.

[0002] Conventionally, when mounting components on a board using a mounting machine, component placement misalignment due to board warpage can occur, resulting in the production of defective boards. To address this issue, it has been proposed to equip mounting machines with a function for detecting the board height. Specifically, a board height sensor mounted on the mounting machine's head irradiates the board with a laser beam and measures the board height from the reflected light. This measurement is then performed at multiple locations on the board to calculate the amount of board warpage. Furthermore, mounting components while taking the measured amount of warpage into account reduces the impact during component mounting, even on warped boards, and optimizes the amount of solder paste crushing, thereby improving board quality. Furthermore, detecting board warpage exceeding a predetermined tolerance can prevent the production of defective boards. Related technologies, for example, are known from Patent Document 1 (International Publication No. 2018 / 216132).

[0003] When measuring the height of a substrate, a user needs to set multiple measurement points for measuring the height of the substrate. However, in conventional techniques, after setting the measurement points, the user must manually perform the following tasks for each measurement point: visually checking the condition of the measurement points and adjusting the coordinates of the measurement points if the condition is poor; and checking the robustness of the measurement points (variation in the measured substrate height values) and adjusting the coordinates of the measurement points if the variation is large. This process places a significant burden on the user. Furthermore, the adjustment of the measurement points is highly dependent on the individual user. Therefore, this specification provides a technique for efficiently adjusting the measurement points for measuring the height of a substrate.

[0004] This specification provides a mounting machine that has the function of automatically determining the position of a measurement point for measuring the board height of a board on which components are mounted. The mounting machine includes an imaging device, an inspection device, and a determination device. The imaging device captures an image of a tentative measurement point placed at a tentative position on the board based on preset imaging conditions. The inspection device uses the captured image of the tentative measurement point to inspect the tentative measurement point and its surrounding conditions and determine whether the position of the tentative measurement point is appropriate. If the inspection device determines that the position of the tentative measurement point is appropriate, the determination device determines that position as the measurement point. However, if the inspection device determines that the position of the tentative measurement point is not appropriate, the determination device does not determine that position as the measurement point. With the above-described configuration, the measurement point is automatically set, thereby reducing the man-hours required to adjust the measurement point and making the adjustment of the measurement point more efficient. Furthermore, user dependency is reduced.

[0005] This specification also provides a mounting machine having a function of automatically determining the position of a measurement point for measuring the board height of a board on which components are mounted. The mounting machine includes a board height sensor, an inspection device, and a determination device. The board height sensor measures the board height of a temporary measurement point placed in a temporary position on the board and its surroundings, and determines the variation in the measured board height values. The inspection device inspects the temporary measurement point and its surrounding conditions based on the magnitude of the variation in the measured board height values, and determines whether the position of the temporary measurement point is appropriate. If the inspection device determines that the position of the temporary measurement point is appropriate, the determination device determines that position as the measurement point. However, if the inspection device determines that the position of the temporary measurement point is not appropriate, the determination device does not determine that position as the measurement point. The above-mentioned configuration can also achieve similar effects.

[0006] Furthermore, this specification provides a board height measurement position determination device that automatically determines the position of a measurement point for measuring the board height of a board on which components are mounted. The board height measurement position determination device includes an imaging device, an inspection device, and a determination device. The imaging device captures an image of a tentative measurement point placed at a tentative position on the board based on preset imaging conditions. The inspection device uses the captured image of the tentative measurement point to inspect the tentative measurement point and its surrounding conditions and determine whether the position of the tentative measurement point is appropriate. If the inspection device determines that the position of the tentative measurement point is appropriate, the determination device determines that position as the measurement point. However, if the inspection device determines that the position of the tentative measurement point is not appropriate, the determination device does not determine that position as the measurement point.

[0007] This specification also provides a board height measurement position determination device that automatically determines the position of a measurement point for measuring the board height of a board on which components are mounted. The board height measurement position determination device includes a board height sensor, an inspection device, and a determination device. The board height sensor measures the board height of a temporary measurement point placed in a temporary position on the board and its surroundings, and determines the variation in the measured board height values. The inspection device inspects the temporary measurement point and its surrounding conditions based on the magnitude of the variation in the measured board height values, and determines whether the position of the temporary measurement point is appropriate. If the inspection device determines that the position of the temporary measurement point is appropriate, the determination device determines that position as the measurement point. However, if the inspection device determines that the position of the temporary measurement point is not appropriate, the determination device does not determine that position as the measurement point.

[0008] This specification also provides a board height measurement position determination method for determining the position of a measurement point for measuring the board height of a board on which components are mounted. The board height measurement position determination method includes an imaging step, an inspection step, and a position correction step. In the imaging step, an imaging device images a tentative measurement point placed at a tentative position on the board based on preset imaging conditions. In the inspection step, the captured image of the tentative measurement point is used to inspect the tentative measurement point and its surrounding conditions, and the appropriateness of the position of the tentative measurement point is determined. In the position correction step, if the position of the tentative measurement point is determined to be appropriate, the position is determined to be the measurement point. However, if the position of the tentative measurement point is determined to be unsuitable, the position is not determined to be the measurement point, and the position of the tentative measurement point is moved, and the imaging step and inspection step are then performed again.

[0009] This specification also provides a method for determining a position for measuring a board height of a board on which components are mounted. The method for determining a position for measuring a board height includes a height variation measurement step, an inspection step, and a position correction step. In the height variation measurement step, the board height of a temporary measurement point placed in a temporary position on the board and its surroundings is measured to determine the variation in the measured board height. In the inspection step, the temporary measurement point and its surrounding conditions are inspected based on the magnitude of the variation in the measured board height, and the appropriateness of the position of the temporary measurement point is determined. In the position correction step, if the position of the temporary measurement point is determined to be suitable, the position is determined to be the measurement point. However, if the position of the temporary measurement point is determined to be unsuitable, the position is not determined to be the position of the measurement point, and the position of the temporary measurement point is moved, and the height variation measurement step and inspection step are performed again.

[0010] 1 is a schematic plan view showing a component mounting system of an embodiment; FIG. 2 is a schematic cross-sectional view showing a mounting machine; FIG. 3 is a schematic view showing a board height sensor; FIG. 4 is a block diagram showing the electrical configuration of the component mounting system; FIG. 5 is a schematic view for explaining a method for determining a board height measurement position; FIG. 6 is a schematic plan view showing a board on which temporary measurement points are arranged; FIG. 7 is a schematic plan view showing a board on which temporary measurement points and component mounting points are arranged; FIG. 8 is a flowchart for explaining a method for determining a board height measurement position; FIG. 9 is an explanatory view showing a captured image; (a) and (b) are histograms showing the luminance distribution in a certain range centered on a temporary measurement point; (b) is a schematic plan view showing the destination of a temporary measurement point; (c) is an explanatory view showing a state when a temporary measurement point moves outside the board; (d) is an explanatory view showing a state when a temporary measurement point moves inside the circumscribing rectangle of a component; and (e) is an explanatory view showing a state when a temporary measurement point moves inside or outside the minimum circumscribing rectangle.

[0011] The mounting machine disclosed in this specification may further include a board height sensor that measures the board height at the temporary measurement point and its surroundings and determines the variation in the measured board height.The inspection device may inspect the temporary measurement point and its surroundings based on the magnitude of the variation in the measured board height and determine whether the position of the temporary measurement point is appropriate.With the above-mentioned configuration, the suitability of the position of the temporary measurement point is determined taking into account the variation in the measured values, so that the measurement point can be determined in an appropriate position.

[0012] The mounting machine disclosed in this specification may further include a notification device that notifies the user that the positions of the temporary measurement points are not suitable when the inspection device determines that the positions of the temporary measurement points are not suitable. With the above-mentioned configuration, the user can recognize that the positions of the temporary measurement points are not suitable.

[0013] The mounting machine disclosed in this specification may further include a repair device that, when the inspection device determines that the position of the tentative measurement point is not suitable, moves the position of the tentative measurement point and then performs imaging by the imaging device and inspection by the inspection device again, or measurement by the board height sensor and inspection by the inspection device again. With the above-mentioned configuration, the repair device corrects the position of the tentative measurement point, thereby reducing the burden on the user.

[0014] In the mounting machine disclosed in this specification, the inspection device may refer to the brightness value of a specified point on the resist surface of the substrate to determine whether the position of the tentative measurement point is appropriate. According to the above-mentioned configuration, since the suitability is determined by referring to the brightness value, it is possible to reduce user dependency and make an objective determination.

[0015] In the mounting machine disclosed in this specification, when the correction device moves the position of the temporary measurement point, the correction device may move the temporary measurement point in a spiral and stepwise manner, starting from the position where the temporary measurement point was initially placed. With the above-mentioned configuration, the correction (movement) of the position of the temporary measurement point can be performed efficiently.

[0016] In the mounting machine disclosed in this specification, the repair device may further try the next destination if the movement of the tentative measurement point to the next destination position involves movement from the inside to the outside of the board, movement from the outside to the inside of the circumscribing rectangle of the component, or movement that crosses the inside and outside of the minimum circumscribing rectangle that surrounds the component. With the above-mentioned configuration, it is possible to try the next destination when there is a possibility that an appropriate measurement point will be found.

[0017] In the mounting machine disclosed in this specification, the repair device may stop moving the position of the temporary measurement point and delete the temporary measurement point when the amount of movement of the position of the temporary measurement point exceeds an upper limit. With the above-mentioned configuration, it is possible to prevent the search for the measurement point from taking an unnecessarily long time.

[0018] (Example) Hereinafter, a board height measurement position determining device and a board height measurement position determining method of this example will be described with reference to the drawings. As shown in Fig. 1, a component mounting system 10 of this example is a system that mounts components 2 (see Fig. 2) on a board 1. The component mounting system 10 is configured by arranging multiple mounting machines 11 along the conveyance direction (X direction) of the board 1. Specific examples of the components 2 include semiconductor packages such as QFPs (Quad Flat Packages) and BGAs (Ball Grid Arrays), and chip components such as chip resistors and chip capacitors.

[0019] A solder printer and a print inspection machine (both not shown) are disposed upstream of each mounting machine 11. The solder printer prints a solder pattern on the lands 3 (see FIG. 9 ) of the board 1 and delivers the printed board 1 to the print inspection machine. The print inspection machine inspects the solder pattern printed on the board 1 and delivers the inspected board 1 to each mounting machine 11. A reflow oven and a board visual inspection machine (both not shown) are disposed downstream of each mounting machine 11. The reflow oven reflows the board 1 delivered from each mounting machine 11. That is, the reflow oven heats the board 1 delivered thereto to melt the solder and solder the components 2 to the board 1. The board visual inspection machine inspects the board 1 after component mounting that is delivered thereto from the reflow oven. The board visual inspection machine inspects whether the components 2 are properly mounted on the board 1. If the components 2 are properly mounted on the board 1 , the board appearance inspection machine carries the board 1 out of the component mounting system 10 .

[0020] 1 and 2, the mounting machine 11 includes a board height measurement position determination device that automatically determines the position of a measurement point for measuring the board height of the board 1. The mounting machine 11 includes a plurality of component feeders 12, an XY robot 13, a board transport device 14, a head unit 21, a parts camera 31, a board height sensor 40, etc.

[0021] Each component feeder 12 stores a plurality of components 2. The component feeders 12 are detachably attached to the feeder holder 15 and supply the components 2 to the head unit 21. The component feeders 12 in this embodiment are tape-type feeders that store a plurality of components 2 on a tape.

[0022] The XY robot 13 moves the head unit 21 in the X and Y directions to move the head unit 21 between above the component feeder 12 and above the substrate 1. The XY robot 13 is composed of guide rails that guide the head unit 21, a movement mechanism that moves the head unit 21 along the guide rails, a motor that drives the movement mechanism, etc. The XY robot 13 is housed inside the housing 16 and is disposed above the substrate 1.

[0023] The board transport device 14 is a device that performs the operations of transporting the board 1 to the work position A1 in the mounting machine 11, positioning the board 1 at the work position A1 before component mounting, and transporting the board 1 from the work position A1 after component mounting. The board transport device 14 in this embodiment can be configured, for example, with a pair of belt conveyors, a support device (not shown) that is attached to the belt conveyors and supports the board 1 from below, and a drive device (not shown) that drives the belt conveyors. The board 1 is transported from the upstream (left side in FIG. 1 ) to the downstream (right side in FIG. 1 ) of the component mounting system 10.

[0024] The head unit 21 is a movable unit that mounts components 2 on the board 1. The head unit 21 includes a component mounting head 22 and a mark camera 24 (image capture device). The component mounting head 22 is attached to the underside of the head unit 21 and includes a plurality of suction nozzles 23. Each suction nozzle 23 is raised and lowered in the vertical direction (Z direction) by an actuator (not shown) housed in the component mounting head 22 and is configured to be able to suck up components 2.

[0025] To mount the component 2 on the board 1 using the head unit 21, first, the suction nozzle 23 is moved downward until the suction surface of the suction nozzle 23 abuts against the component 2 stored in the component feeder 12. Next, the suction nozzle 23 picks up the component 2 and then moves the suction nozzle 23 upward. Once the process of picking up the component 2 onto the suction nozzle 23 is complete, the XY robot 13 is driven to position the head unit 21 relative to the board 1. Then, the suction nozzle 23 is lowered toward the board 1, thereby mounting the component 2 on the board 1.

[0026] The mark camera 24 is mounted in the head unit 21 near the component mounting head 22 and is configured to be movable together with the component mounting head 22. The mark camera 24 moves above the board 1 that has been carried into the work position A1 by the board transport device 14, and captures an image of a mark (not shown) affixed to the board 1. The mark camera 24 is configured using an imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), for example.

[0027] The part camera 31 is provided between the component feeder 12 and the board transport device 14, below the movement path of the head unit 21. The part camera 31 captures images of the components 2 picked up by the head unit 21 from below. The part camera 31 is also configured using an imaging element such as a CCD or CMOS.

[0028] The substrate height sensor 40 is a sensor that measures the substrate height, which is the height (position in the Z direction) of the upper surface of the substrate 1. The substrate height sensor 40 is attached to the underside of the head unit 21 and moves in the X and Y directions as the head unit 21 moves. In this embodiment, the substrate height sensor 40 is a laser height sensor and includes an irradiation unit 41 and a detection unit 42 (see FIG. 3 ). The irradiation unit 41 irradiates the substrate 1 below the substrate height sensor 40 with laser light L1 obliquely downward. Reflected light L2 of the laser light L1 that reaches the substrate 1 is input to the detection unit 42. As shown in FIG. 3 , the optical path of the reflected light L2 changes depending on the height of the upper surface of the substrate 1 (substrate height), and the incident position of the reflected light L2 on the detection unit 42 also changes. The detection unit 42 detects the distance between the substrate height sensor 40 and the upper surface of the substrate 1 based on the incident position of the reflected light L2 and calculates the substrate height based on the detected distance.

[0029] As shown in FIG. 4 , the component mounting system 10 includes a control device 50 that controls the mounter 11. The control device 50 is a computer that includes a CPU 51, a ROM 52, a HDD 53, a RAM 54, an input / output interface 55, and the like. The control device 50 is also connected to the XY robot 13, the board transport device 14, the component mounting head 22, the mark camera 24, the parts camera 31, the board height sensor 40, and a display device 43. The display device 43 is a touch panel type display device that allows a user U1 (see FIG. 5 ) to input data and display the details of the work. The ROM 52 stores a basic program for supplying solder paste to the board 1.

[0030] Furthermore, a management device 60 that manages each mounting machine 11 is connected to the control device 50 via a bus so that they can communicate with each other. Each control device 50 controls the operation of each unit (component feeder 12, XY robot 13, board transport device 14, head unit 21, parts camera 31, ...) based on a production program stored in the management device 60. Through this control, each control device 50 executes a mounting process for mounting multiple components 2 on a board 1, etc.

[0031] The management device 60 is a device that manages the entire component mounting system 10. As shown in FIG. 4 , the management device 60 is a computer configured with a CPU 61, a ROM 62, a HDD 63, a RAM 64, an input / output interface 65, etc. The management device 60 is also connected to an input device 66 such as a keyboard or a mouse, and a display device 67 such as an LCD. Input signals are input to the management device 60 from the input device 66 via the input / output interface 65. The management device 60 also outputs image signals to the display device 67 via the input / output interface 65. The management device 60 transmits and receives information to and receives information from the control device 50 of the mounting machine 11 via the input / output interface 65. The HDD 63 of the management device 60 stores a production program for the board 1, etc. The production program for the board 1 includes information for each mounting machine 11 in the component mounting system 10, such as information instructing the mounting machine 11 on which board 1 each mounting machine 11 should mount which components 2, in which position on which board 1, and in what order, and information instructing the number of boards 1 each mounting components 2 on should be produced. The production program also includes information regarding the height (thickness) of the part 2 and the width and length of the part 2 in the horizontal direction (dimensions in the X and Y directions).

[0032] Next, a method for determining board height measurement positions will be described. As shown in FIG. 5 , user U1 creates a job (board height measurement job) to determine measurement points for measuring the board height, and transmits the created job to the CPU 61 of the management device 60. Next, the CPU 61 places temporary measurement points M1 (see FIG. 6 ) at temporary positions on the board 1 (see “1.” in FIG. 5 ). The CPU 61 arranges the temporary measurement points M1 at equal intervals based on the size of the board 1, without taking into account the components 2 to be mounted. As shown in FIG. 6 , the temporary measurement points M1 are arranged at equal intervals along both the length L and width W of the board 1, and are arranged in a grid pattern overall. Note that an image representing the board 1 on which the temporary measurement points M1 are arranged is displayed, for example, on the display device 67 of the management device 60. Furthermore, the CPU 61 may superimpose the temporary measurement points M1 arranged on the board 1 and the area where the components 2 to be mounted on the board 1 exist (e.g., the circumscribed rectangle of the components 2) on the image representing the board 1 displayed on the display device 67, based on information about the components 2 included in the production program. This allows the user U1 to easily determine whether the temporary measurement point M1 and the part 2 are at the same position.

[0033] Next, user U1 visually checks whether or not temporary measurement point M1 overlaps part 2, and if temporary measurement point M1 overlaps part 2, corrects it so that temporary measurement point M1 is positioned so that it does not overlap part 2 (see "2." in FIG. 5). Specifically, user U1 corrects (adjusts) the coordinates of temporary measurement point M1 by operating input device 66 of management apparatus 60.

[0034] Furthermore, the CPU 61 of the management device 60 also checks whether the temporary measurement point M1 overlaps the component 2 (see "3." in FIG. 5). Then, the CPU 61 determines whether multiple temporary measurement points M1 surround the mounting point M2 of the component 2 (see FIG. 7) (see "4." in FIG. 5). Thereafter, the user U1 transmits a job to the CPU 61 of the management device 60, and the CPU 61 transmits the job to the CPU 51 of the mounting machine 11.

[0035] Next, user U1 sets the inspection conditions in step S10 shown in FIG. 8 . Specifically, user U1 specifies (selects) the imaging conditions (such as shutter speed) for the inspection and the resist surface R1 (see FIG. 9 ) for placing the temporary measurement point M1. More specifically, user U1 first inputs the imaging conditions for the inspection by operating the display device 43. Next, the control device 50 (CPU 51) of the mounting machine 11 drives the mark camera 24 to capture an image of the board 1 and presents the captured image 71 (see FIG. 9 ) to user U1 (displays it on the display device 43). User U1 checks the captured image 71 on the display device 43. If the luminance difference between the measured resist surface R1 and other surfaces (specifically, the surface of the land 3, the surface of the silk-screened portion, etc.) is small, user U1 resets the imaging conditions to increase the luminance difference, and the CPU 51 re-images the board 1 based on the reset imaging conditions to check the luminance difference. After checking the brightness difference, the user U1 next specifies a point R2 (see FIG. 9 ) on the resist surface R1 to be measured on the captured image 71. The CPU 51 then stores (registers) in the RAM 54 the imaging conditions and the brightness value on the resist surface R1 specified by the user U1 (the correct brightness value).

[0036] Next, the CPU 51 determines the number of tentative measurement points M1 for judging the suitability of the positions. Then, the CPU 51 performs the process of step S20 (imaging step), and images the target tentative measurement point M1 from among the multiple tentative measurement points M1 (see FIGS. 6 and 7) arranged in tentative positions on the substrate 1 based on the imaging conditions stored (set) in the RAM 54 in step S10, with the mark camera 24.

[0037] Next, the CPU 51 (inspection device) performs the process of step S30 (inspection step), inspecting the temporary measurement point M1 and its surroundings using the captured image 72 (see FIG. 10) of the temporary measurement point M1 and determining whether the position of the temporary measurement point M1 is appropriate. Specifically, the CPU 51 first performs the process of step S40, determining whether the position of the temporary measurement point M1 is appropriate by referring to the brightness value of point R2 on the resist surface R1 stored in RAM 54. Specifically, the CPU 51 determines whether the variance of the brightness values ​​within a certain range H1 (see FIG. 10) centered on the temporary measurement point M1 is less than a threshold value. The certain range H1 is a square range in a plan view. FIG. 10 also shows a histogram showing the brightness distribution within the certain range H1 centered on the temporary measurement point M1. For example, if there is no land 3 or the like near the temporary measurement point M1 (see FIG. 10(a)), the brightness distribution will be a single group G1, and the variance of the brightness values ​​will be small. On the other hand, if a land 3 or the like is present around the temporary measurement point M1 (see FIG. 10B), the luminance distribution will be divided into multiple (two in this embodiment) groups G1, resulting in a large variance of the luminance values. If it is determined that the variance is less than the threshold, the CPU 51 proceeds to processing in step S50. On the other hand, if it is determined that the variance is equal to or greater than the threshold, the CPU 51 proceeds to processing in step S90.

[0038] The variance threshold in this embodiment is a default value (prescribed value) determined experimentally, but can be adjusted appropriately by the user U1 depending on the state and image of the substrate 1. Furthermore, the "certain range H1 centered on the tentative measurement point M1" is a range for checking "robustness (variation in the measured values ​​of the substrate height)" in step S60.

[0039] Next, the CPU 51 performs processing in step S50 to determine whether or not there are any lands 3 or the like at or around the temporary measurement point M1. Specifically, the CPU 51 determines whether or not the difference in brightness between the brightness value of the temporary measurement point M1 and the correct brightness value stored in the RAM 54 in step S10 is less than a threshold value. If it is determined that the brightness difference is less than the threshold value, the CPU 51 proceeds to processing in step S60. On the other hand, if it is determined that the brightness difference is equal to or greater than the threshold value, the CPU 51 proceeds to processing in step S90. Note that the brightness difference threshold value in this embodiment is a default value (prescribed value) determined experimentally, but can be adjusted as appropriate by the user U1 depending on the state of the board 1 and the image.

[0040] In step S60, the CPU 51 (inspection device) performs an inspection using the board height sensor 40. In this embodiment, the CPU 51 checks the "robustness (variation in board height measurements)" at the position of the target temporary measurement point M1. Specifically, the CPU 51 performs a height variation measurement step, measuring the board height at the temporary measurement point M1 and its surroundings using the board height sensor 40, and determining the variation in the board height measurements. The CPU 51 then performs an inspection step, inspecting the situation of the temporary measurement point M1 and its surroundings based on the magnitude of the variation in the board height measurements, and determining whether the position of the temporary measurement point M1 is appropriate. Specifically, the CPU 51 performs step S70, inspecting whether the variation in the board height measurements is less than a threshold value. If it is determined that the position of the temporary measurement point M1 is suitable (the warpage of the substrate 1 is small) because the variation in the measured values ​​of the substrate height is less than the threshold value, the CPU 51 (determining device) determines the position of the temporary measurement point M1 as the measurement point (step S80). Note that the CPU 51 repeats the process of step S20 until the determination for all of the temporary measurement points M1 is completed.

[0041] On the other hand, if it is determined that the position of the temporary measurement point M1 is not suitable (the warpage of the substrate 1 is large) because the variation in the measured values ​​of the substrate height is greater than the threshold value, the CPU 51 (determining device) does not determine the position of the temporary measurement point M1 as the position of the measurement point. In this case, the CPU 51 proceeds to the processing of step S90.

[0042] In step S90 (position correction step), the CPU 51 (correction device) moves the position (coordinates) of the temporary measurement point M1 to correct the temporary measurement point M1. For example, when moving the position of the temporary measurement point M1, the CPU 51 moves the temporary measurement point M1 in a spiral and stepwise manner, starting from the position of the initially placed temporary measurement point M1 as a starting point S1 (see "A" in FIG. 11). Note that the amount of movement of the temporary measurement point M1 (for example, the width from "A" to "B") is the same as the length of one side of a certain range H1 (see FIG. 10), which is a range for checking "robustness."

[0043] If the process returns to step S90 after the temporary measurement point M1 has been moved, the temporary measurement point M1 moves as follows. For example, if the temporary measurement point M1, whose starting point S1 is "A," has been moved to step S90 four times, the temporary measurement point M1 will move to "B," "C," "D," and "E" in this order. The movement of the temporary measurement point M1 is repeated until the process no longer returns to step S90. However, if the amount of movement of the temporary measurement point M1 exceeds an upper limit, the process to step S90 is terminated and the temporary measurement point M1 is deleted. Here, the upper limit of the amount of movement is equal to the distance between the temporary measurement points M1 when the temporary measurement points M1 are placed at their temporary positions (see "1." in FIG. 5) (see FIG. 6).

[0044] However, if any of the following conditions apply, the destination of the temporary measurement point M1 is changed to another destination. For example, if the movement of the temporary measurement point M1 is from the inside to the outside of the board 1 (see arrow F1 in FIG. 12 ) or from the outside to the inside of the circumscribing rectangle 2 a (see FIG. 13 ) of the component 2 (see arrow F2 in FIG. 13 ), the destination of the temporary measurement point M1 is changed. Furthermore, if the movement of the temporary measurement point M1 traverses the inside and outside of the minimum circumscribing rectangle 2 b (see FIG. 14 ) that surrounds all the components 2 on the board 1, specifically, if the movement is from the outside to the inside of the minimum circumscribing rectangle 2 b (see arrow F3 in FIG. 14 ) or from the inside to the outside of the minimum circumscribing rectangle 2 b (see arrow F4 in FIG. 14 ), the destination of the temporary measurement point M1 is also changed.

[0045] Thereafter, the CPU 51 proceeds to the processing of step S30 again. That is, if the CPU 51 determines that the position of the temporary measurement point M1 is not suitable, it moves the position of the temporary measurement point M1 and then causes the measurement by the board height sensor 40 and the inspection by the inspection device (CPU 51) to be performed again. Furthermore, the CPU 51 repeats the processing of steps S20 to S90 until the positions of all the temporary measurement points M1 are determined to be suitable and determined as measurement points. Then, when the positions of all the temporary measurement points M1 have been determined as measurement points, the CPU 51 ends this processing.

[0046] As described above, the mounting machine 11 of this embodiment uses the mark camera 24 to capture an image of the temporary measurement point M1 placed at a temporary position on the board 1 based on preset imaging conditions. The CPU 51 uses the captured image 72 of the temporary measurement point M1 to inspect the temporary measurement point M1 and its surrounding conditions and determine whether the position of the temporary measurement point M1 is appropriate. Therefore, the mounting machine 11 of this embodiment automatically determines whether the position of the temporary measurement point M1 is appropriate and automatically determines whether the position of the temporary measurement point M1 should be used as the measurement point. Furthermore, if the position of the temporary measurement point M1 is inappropriate, the CPU 51 automatically moves (corrects) the position of the temporary measurement point M1 to a suitable position. In other words, the measurement point for measuring the board height is automatically set. This reduces the labor required to adjust the measurement point and makes the adjustment of the measurement point more efficient. Furthermore, because the measurement point adjustment is performed by the mounting machine 11, the burden on the user U1 is reduced, and the user U1's personal preferences are alleviated, resulting in consistent quality of the board 1.

[0047] In the mounting machine 11 of this embodiment, if the variance of the brightness values ​​within a certain range H1 (see FIG. 10 ) centered on a temporary measurement point M1 is less than a threshold value, the temporary measurement point M1 is determined as the measurement point, and the board height is measured by the board height sensor 40. Note that if the variance of the brightness values ​​is small, the brightness distribution will be a single group G1, and there is a high possibility that lands 3 and the like are not present around the temporary measurement point M1 (see FIG. 10( a)). Therefore, by measuring the board height at a position where the variance of the brightness values ​​is less than the threshold value, it is possible to prevent the thickness of the solder present on the lands 3 from being added to the board height. This allows for more accurate measurement of the board height.

[0048] In the component mounting system 10 of this embodiment, the process of placing a temporary measurement point M1 at a temporary position on the board 1 (see "1." in FIG. 5) and the process of determining whether the position of the temporary measurement point M1 is appropriate (see "3." and "4." in FIG. 5) are performed by a management device 60 outside the mounter 11, rather than by the control device 50 of the mounter 11. This reduces the burden on the control device 50.

[0049] Although the above describes an embodiment, the specific aspects are not limited to the above embodiment. In the above embodiment, the inspection steps (steps S30 to S50) using the mark camera 24 are performed after the inspection steps (steps S60 and S70) using the board height sensor 40. However, the present invention is not limited to this configuration. For example, in other embodiments, the inspection steps (steps S30 to S50) using the mark camera 24 may be performed after the inspection steps (steps S60 and S70) using the board height sensor 40. Furthermore, either the inspection step using the mark camera 24 or the inspection step using the board height sensor 40 may be omitted. Furthermore, among the inspection steps using the mark camera 24, either the process of determining whether the variance of the brightness values ​​in a certain range H1 centered on the temporary measurement point M1 is less than a threshold value (step S40) or the process of determining whether the brightness difference between the brightness value of the temporary measurement point M1 and the correct brightness value is less than a threshold value (step S50) may be omitted.

[0050] 5, the CPU 61 of the management device 60 places the temporary measurement point M1 at a temporary position on the board 1, but this is not limiting. For example, in another embodiment, the CPU 51 of the mounting machine 11 may place the temporary measurement point M1 at a temporary position on the board 1.

[0051] In the above embodiment, the substrate height sensor 40 is a laser height sensor that uses the laser light L1, but the present invention is not limited to this configuration. For example, in other embodiments, the sensor that measures the substrate height may be a contact-type height sensor or an ultrasonic-type height sensor.

[0052] In the above embodiment, a notification device may be further provided that notifies the user that the position of the temporary measurement point M1 is not suitable when the CPU 51 determines that the position of the temporary measurement point M1 is not suitable. Examples of the notification device include the display device 43 of the mounting machine 11 and the display device 67 of the management device 60. Alternatively, an audio output means such as a speaker that notifies the user that the position of the temporary measurement point M1 is not suitable may be used as the notification device.

[0053] In the above embodiment, the temporary measurement point M1 is automatically corrected (step S90), but the present invention is not limited to this configuration. For example, in another embodiment, the user U1 may correct the temporary measurement point M1, and the CPU 51 may only notify the user of the temporary measurement point M1 that needs to be corrected or suggest a destination for the temporary measurement point M1.

[0054] In the above embodiment, the mounting machine 11 includes the board height measurement position determining device, but this is not limited to this configuration. For example, in other embodiments, a device other than the mounting machine 11 (such as a printing machine) may include the board height measurement position determining device.

[0055] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The claimed technology includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives alone is technically useful.

[0056] 1: Board 2: Component 2a: Circumscribed rectangle 2b: Minimum circumscribed rectangle 11: Mounting machine 24: Mark camera as an imaging device 40: Board height sensor 43, 67: Display device as a notification device 51: CPU as an inspection device, a determination device, and a correction device 72: Captured image of a tentative measurement point M1: Tentative measurement point R1: Resist surface R2: Point specified on the resist surface S1: Starting point

Claims

1. A mounting machine having a function of automatically determining the position of a measurement point for measuring the board height of a board on which a component is to be mounted, comprising: an imaging device which images a tentative measurement point placed at a tentative position on the board based on preset imaging conditions; an inspection device which uses the image of the tentative measurement point to inspect the tentative measurement point and its surrounding conditions and judges whether the position of the tentative measurement point is appropriate; and a determination device which, if the inspection device determines that the position of the tentative measurement point is appropriate, determines that position as the measurement point, but, if the inspection device determines that the position of the tentative measurement point is not appropriate, does not determine that position as the measurement point.

2. A mounting machine having a function of automatically determining the position of a measurement point for measuring the board height of a board on which a component is mounted, comprising: a board height sensor that measures the board height of a tentative measurement point placed in a tentative position on the board and its surroundings, and determines the variation in the measured values ​​of the board height; an inspection device that inspects the tentative measurement point and its surrounding conditions based on the magnitude of the variation in the measured values ​​of the board height, and determines whether the position of the tentative measurement point is appropriate; and a determination device that, if the inspection device determines that the position of the tentative measurement point is appropriate, determines that position as the measurement point, but, if the inspection device determines that the position of the tentative measurement point is not appropriate, does not determine that position as the position of the measurement point.

3. The mounting machine of claim 1, further comprising a board height sensor that measures the board height of the tentative measurement point and its surroundings and determines the variation in the measured board height values, and wherein the inspection device inspects the tentative measurement point and its surrounding conditions based on the magnitude of the variation in the measured board height values ​​and determines whether the position of the tentative measurement point is appropriate.

4. A mounting machine as described in any one of claims 1 to 3, further comprising a notification device that notifies the user that the position of the tentative measurement point is not suitable when the inspection device determines that the position of the tentative measurement point is not suitable.

5. A mounting machine as described in any one of claims 1 to 3, further comprising a correction device which, when the inspection device determines that the position of the tentative measurement point is not suitable, moves the position of the tentative measurement point and then performs imaging by the imaging device and inspection by the inspection device, or measurement by the board height sensor and inspection by the inspection device again.

6. A mounting machine according to any one of claims 1 to 3, wherein the inspection device judges whether the position of the tentative measurement point is appropriate by referring to the brightness value of a specified point on the resist surface on the board.

7. The mounting machine according to claim 5, wherein, when the correction device moves the position of the tentative measurement point, the correction device moves the tentative measurement point in a spiral manner and in stages, starting from the position where the tentative measurement point was initially placed.

8. The mounting machine according to claim 5, wherein the repair device further attempts to move the tentative measurement point to a next destination position if the movement to that next destination position involves movement from the inside to the outside of the board, movement from the outside to the inside of the circumscribing rectangle of the component, or movement that crosses between the inside and outside of a minimum circumscribing rectangle that surrounds the component.

9. The mounting machine according to claim 5, wherein the correction device stops moving the position of the tentative measurement point and deletes the tentative measurement point when the amount of movement of the position of the tentative measurement point exceeds an upper limit.

10. A device for automatically determining the position of a measurement point for measuring the height of a board on which components are mounted, comprising: an imaging device for imaging a tentative measurement point placed at a tentative position on the board based on preset imaging conditions; an inspection device for inspecting the tentative measurement point and its surrounding conditions using the captured image of the tentative measurement point and determining whether the position of the tentative measurement point is appropriate; and a determination device for determining the position of the tentative measurement point as the measurement point if the inspection device determines that the position of the tentative measurement point is appropriate, but not determining that position as the measurement point if the inspection device determines that the position of the tentative measurement point is not appropriate.

11. A board height measurement position determination device that automatically determines the position of a measurement point for measuring the board height of a board on which components are mounted, comprising: a board height sensor that measures the board height of a tentative measurement point placed in a tentative position on the board and its surroundings, and determines the variation in the measured board height values; an inspection device that inspects the tentative measurement point and its surrounding conditions based on the magnitude of the variation in the measured board height values, and determines whether the position of the tentative measurement point is appropriate; and a determination device that determines the position of the tentative measurement point as the measurement point if the inspection device determines that the position is appropriate, but does not determine the position of the tentative measurement point as the position of the measurement point if the inspection device determines that the position is not appropriate.

12. A method for determining a position of a measurement point for measuring the height of a board on which components are mounted, comprising: an imaging step of imaging a tentative measurement point placed at a tentative position on the board with an imaging device based on preset imaging conditions; an inspection step of inspecting the tentative measurement point and its surrounding conditions using the captured image of the tentative measurement point to determine whether the position of the tentative measurement point is appropriate; and a position correction step of not determining the position of the tentative measurement point as the measurement point if it is determined that the position is appropriate, but moving the position of the tentative measurement point and then executing the imaging step and the inspection step again if it is determined that the position of the tentative measurement point is not appropriate.

13. A method for determining a position of a measurement point for measuring the board height of a board on which components are mounted, comprising: a height variation measurement step of measuring the board height of a tentative measurement point placed in a tentative position on the board and its surroundings, and determining the variation in the measured board height values; an inspection step of inspecting the tentative measurement point and its surrounding conditions based on the magnitude of the variation in the measured board height values, and judging whether the position of the tentative measurement point is appropriate; and a position correction step of not determining the position of the tentative measurement point as the measurement point if it is determined that the position is appropriate, but not determining that the position of the tentative measurement point as the measurement point if it is determined that the position is not appropriate, and moving the position of the tentative measurement point, and then executing the height variation measurement step and the inspection step again.

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