JP7774236B2 - Component mounting system and component mounting method - Google Patents

Description

The present invention relates to a component mounting system and a component mounting method for mounting components on a substrate.

A known component mounting system for mounting components on a board is equipped with an inspection device that inspects the mounting condition, such as misalignment, of components mounted on the board by the component mounting device. The inspection device calculates a correction value for mounting the components on the board based on the inspection results, and the component mounting device then mounts the components on the board based on the correction value (see, for example, Patent Document 1). The system described in Patent Document 1 discloses that it is possible to grasp the effect of correction through feedback of inspection results by displaying a post-correction evaluation value based on the inspection results and correction values in a way that makes it possible to compare the post-correction evaluation value with the evaluation value that would be obtained if no correction were made.

Japanese Patent Application Laid-Open No. 2017-139364

However, due to variations in the component shape and external dimensions, there are known components for which the mounting state becomes unstable when correction values are fed back from inspection results and the components are mounted. For this reason, there is room for further improvement in order to achieve good mounting accuracy for the diverse components mounted on boards.

The present invention therefore aims to provide a component mounting system and component mounting method that can achieve good mounting accuracy for a variety of components mounted on a board.

The component mounting system of the present invention includes a nozzle that holds a component, an imaging unit that images the component held by the nozzle, an acquisition unit that acquires first positional deviation information of the component relative to the nozzle based on the captured image, a correction value calculation unit that calculates a correction value when mounting the component on a board based on board inspection information that includes at least second positional deviation information of the component mounted on the board, a component mounting unit that mounts the component held by the nozzle on the board based on the first positional deviation information and the correction value, and a judgment unit that judges whether or not to use the correction value during mounting based on the first positional deviation information, wherein the judgment unit judges that the correction value should be used if the distribution of data related to the first positional deviation information follows a normal distribution .
Furthermore, the component mounting system of the present invention includes a nozzle that holds a component, an imaging unit that images the component held by the nozzle, an acquisition unit that acquires first positional deviation information of the component relative to the nozzle based on the captured image, a correction value calculation unit that calculates a correction value for mounting the component on the board based on board inspection information that includes at least second positional deviation information of the component mounted on the board, a component mounting unit that mounts the component held by the nozzle on the board based on the first positional deviation information and the correction value, and a judgment unit that judges whether or not to use the correction value during mounting based on the first positional deviation information, and if the distribution of data related to the first positional deviation information does not follow a normal distribution, the judgment unit judges whether or not to use the correction value based on the kurtosis of the data.

The component mounting method of the present invention captures an image of a component held by a nozzle, obtains first positional deviation information of the component relative to the nozzle based on the captured image, mounts the component on a board based on the first positional deviation information, determines whether or not to use a correction value during mounting based on the first positional deviation information, and if it is determined that the correction value should be used, calculates the correction value based on second positional deviation information of the component mounted on the board, then mounts the component on the board based on the first positional deviation information and the correction value, and in determining whether or not to use the correction value, determines that the correction value should be used if the distribution of data related to the first positional deviation information follows a normal distribution .
Furthermore, the component mounting method of the present invention includes capturing an image of a component held by a nozzle, obtaining first positional deviation information of the component relative to the nozzle based on the captured image, mounting the component on a board based on the first positional deviation information, determining whether or not to use a correction value during mounting based on the first positional deviation information, and if it is determined that the correction value should be used, calculating the correction value based on second positional deviation information of the component mounted on the board, and then mounting the component on the board based on the first positional deviation information and the correction value. In determining whether or not to use the correction value, if the distribution of data related to the first positional deviation information does not follow a normal distribution, determining whether or not to use the correction value is based on the kurtosis of the data.

This invention makes it possible to achieve good mounting accuracy for a variety of components mounted on a board.

FIG. 1 is a diagram illustrating the configuration of a component mounting system according to an embodiment of the present invention. FIG. 1 is a plan view showing a configuration of a main part of a component mounting device provided in a component mounting system according to an embodiment of the present invention. FIG. 1 is a side view showing a configuration of a main part of a component mounting apparatus according to an embodiment of the present invention; FIG. 1 is a diagram illustrating the configuration of a mounting head and a component supply unit of a component mounting device according to an embodiment of the present invention; FIG. 1 is a block diagram showing the configuration of a control system of a component mounting system according to an embodiment of the present invention. FIG. 10 is an explanatory diagram of the amount of component mounting position deviation acquired by the inspection device according to the embodiment of the present invention. FIG. 10 is an explanatory diagram of the amount of component pickup position deviation acquired in the component mounting device according to the embodiment of the present invention; FIG. 10 is an explanatory diagram of the relationship between the pickup position deviation amount and the correction value during mounting in the component mounting device according to the embodiment of the present invention. FIG. 1A is an explanatory diagram of an example of a normal distribution of pickup position deviation amounts acquired in a component mounting system according to an embodiment of the present invention; FIG. 1B is an explanatory diagram of an example of a non-normal distribution with high kurtosis; and FIG. 1C is an explanatory diagram of an example of a non-normal distribution with low kurtosis. 1A and 1B are diagrams illustrating an example of a component that may be subject to significant positional deviation when a calculated correction value is used in a component mounting system according to an embodiment of the present invention; FIG. 1B is an explanatory diagram illustrating an image of a pickup position; FIG. 1C is a plan view illustrating a state where the component is mounted on a board; and FIG. 1C is a side view illustrating a state where the component is mounted on a board. 1 is a flow diagram of a component mounting method in a component mounting system according to an embodiment of the present invention;

An embodiment of the present invention will be described in detail below using the drawings. The configurations, shapes, etc. described below are examples for explanatory purposes and can be modified as appropriate depending on the specifications of the component mounting system, management computer, component mounting device, and inspection device. Corresponding elements in all drawings will be denoted by the same reference numerals, and duplicate explanations will be omitted. In Figure 2 and in some sections described below, two axes that intersect at right angles in the horizontal plane are shown: the X-axis (left-right direction in Figure 2) in the board transport direction, and the Y-axis (up-down direction in Figure 2) that is perpendicular to the board transport direction. In Figure 3 and in some sections described below, the Z-axis (up-down direction in Figure 3) is shown as the height direction that is perpendicular to the horizontal plane. In Figure 4 and in some sections described below, the θ direction, which is the direction of rotation around the Z-axis, is shown.

First, the configuration of component mounting system 1 will be described with reference to Figure 1. Component mounting system 1 has the function of mounting components on a board to produce a mounted board. Component mounting system 1 is equipped with solder printing device M1, component mounting devices M2 and M3, and inspection device M4. These devices are connected to management computer 3 via communication network 2. Note that the number of component mounting devices M2 and M3 equipped in component mounting system 1 is not limited to two, and may be one, three, or more.

The solder printing device M1 screen-prints cream solder for component bonding onto the target board. The component mounting devices M2 and M3 perform component mounting operations in which the component mounting unit 12 retrieves components from the component supply unit 7 and transfers and mounts them onto the board 6 on which the cream solder for component bonding has been printed (see Figure 2). The inspection device M4 uses an inspection camera 32 (see Figure 5) to inspect the component mounting status on the board 6 on which components have been mounted by the component mounting devices M2 and M3, obtaining information such as deviations in the mounting position from the correct position of the components, and judging the quality of the mounted board. In addition to its line management function, the management computer 3 has the function of judging the appropriateness of the use of correction values by the component mounting devices M2 and M3 based on the deviations in the component pickup position information obtained by the component mounting devices M2 and M3.

Next, the configuration of component mounting devices M2 and M3 will be described with reference to Figures 2 and 3. Figure 3 schematically shows a portion of component mounting devices M2 and M3 in Figure 2. Component mounting devices M2 and M3 have the function of performing mounting work, which involves mounting components supplied from a component supply unit 7 onto a board 6. In Figure 2, a board transport mechanism 5 is arranged along the X axis in the center of the base 4. The board transport mechanism 5 transports the board 6 transported from upstream to the mounting work position, positions it, and holds it. The board transport mechanism 5 also transports the board 6 downstream after the component mounting work has been completed.

Component supply units 7 are located on both sides (front and rear) of the board transport mechanism 5. Each component supply unit 7 has multiple tape feeders 8 arranged along the X axis. The tape feeders 8 feed a carrier tape, on which pockets for storing components are formed, at a pitch in a direction (tape feed direction) from the outside of the component supply unit 7 toward the board transport mechanism 5, thereby supplying components to the component suction position where the mounting head 11 of the component mounting unit 12 picks up the components.

In Figures 2 and 3, a Y-axis table 9 equipped with a linear drive mechanism is arranged along the Y-axis at both ends of the X-axis on the top surface of the base 4. Two beams 10 (on the front and rear sides), also equipped with linear drive mechanisms, are connected to the Y-axis table 9 so that they can move freely along the Y-axis. The beams 10 are arranged along the X-axis. A mounting head 11 is attached to each of the two beams 10 so that it can move freely along the X-axis. The mounting head 11 is equipped with multiple (eight in this example) suction units 11a that can lift and lower and pick up and hold components D. A nozzle 11b that picks up and holds a component D is attached to the lower end of each suction unit 11a.

In Figure 2, by driving the Y-axis table 9 and beam 10, the mounting head 11 moves horizontally (X-axis direction, Y-axis direction). As a result, the two mounting heads 11 use nozzles 11b to pick up and remove components D from the component suction positions of the tape feeders 8 arranged in the corresponding component supply units 7, and then mount them at the mounting points on the board 6 positioned by the board transport mechanism 5. In other words, the Y-axis table 9, beam 10, and mounting heads 11 constitute the component mounting unit 12 that mounts components D on the board 6.

In Figures 2 and 3, a component recognition camera 13 is disposed between the component supply unit 7 and the board transport mechanism 5. As the mounting head 11, which has picked up a component D from the component supply unit 7, moves above the component recognition camera 13, the component recognition camera 13 captures an image of the component D held by the nozzle 11b. In other words, the component recognition camera 13 is an imaging unit that captures an image of the component D held by the nozzle 11b. From the imaging results, information on the pickup position deviation of the component D relative to the nozzle 11b is obtained. A head camera 14 is attached to the plate 10a on which the mounting head 11 is attached. The head camera 14 moves integrally with the mounting head 11.

As the mounting head 11 moves, the head camera 14 moves above the board 6 positioned by the board transport mechanism 5 and captures an image of a board mark (not shown) provided on the board 6. The position of the board 6 is recognized from the image capture results. The head camera 14 also moves above the component suction position of the tape feeder 8 and captures an image of the component D housed on the carrier tape near the component suction position. The image capture results indicate the state of the supplied component D. When the mounting head 11 mounts components on the board 6, the mounting position is corrected taking into account the image capture results of the component D taken by the component recognition camera 13 and the image capture results of the board position taken by the head camera 14.

In Figure 2, touch panels 15 operated by the workers are installed at the front and rear of component mounting devices M2 and M3, respectively, at positions where workers work. The touch panels 15 display various information on their display units, and workers input data and operate component mounting devices M2 and M3 using operation buttons and other controls displayed on the display units.

In Figure 3, a carriage 16 with multiple tape feeders 8 pre-installed on the feeder base 16a is set in the component supply unit 7. The feeder base 16a has multiple slots for installing the tape feeders 8. The tape feeders 8 installed on the carriage 16 are managed based on the position of the installed slot and the position (front or rear) of the carriage 16 installed on the component mounting devices M2 and M3. The carriage 16 holds a tape reel 18 that stores a wound carrier tape 17 holding components D. The carrier tape 17 pulled out from the tape reel 18 is pitch-fed to the component suction position by a tape feed mechanism (not shown) built into the tape feeder 8.

Next, the configuration of the mounting head 11 will be described with reference to Figure 4. The mounting head 11 is equipped with multiple suction units 11a, each equipped with a drive mechanism (not shown). By driving the drive mechanism, a shaft 11c with a nozzle 11b attached to its lower end moves up and down (arrow a), and the shaft 11c rotates, causing the nozzle 11b to rotate in the θ direction around the nozzle axis AN (arrow b).

Next, the configuration of the control system of component mounting system 1 will be described with reference to Figure 5. Among the functions possessed by component mounting system 1, the following will focus on the function of determining whether or not to use correction values in component mounting devices M2 and M3 based on pickup position deviation information (first position deviation information) of component D held by nozzle 11b. Management computer 3, component mounting devices M2 and M3, and inspection device M4 are interconnected via communication network 2. Component mounting devices M2 and M3 each include a mounting control device 20, a board transport mechanism 5, a tape feeder 8, a component mounting unit 12, a component recognition camera 13, a head camera 14, and a touch panel 15. Mounting control device 20 includes a mounting memory unit 21, an acquisition unit 22, a mounting control unit 23, and a mounting communication unit 24.

The mounting communication unit 24 transmits and receives data between the inspection device M4 and the management computer 3 via the communication network 2. The mounting memory unit 21 is a storage device that stores mounting data 21a, correction value information 21b, correction suitability information 21c, suction deviation information 21d, etc. The mounting data 21a includes information such as the production model name of the mounting board (board name), the type of component D (component name) to be mounted on the board 6, the mounting position (XY coordinates), the mounting direction (θ direction), the installation position of the tape feeder 8 that supplies the component D, and the installation position of the nozzle 11b.

Correction value information 21b stores correction values calculated by inspection device M4 when mounting component D on board 6, based on an image of component D mounted on board 6. Correction suitability information 21c stores, for each type of component D, information on whether or not to use a correction value when mounting component D on board 6. The acquisition unit 22 acquires pickup position deviation information (pickup position deviation amounts Xb, Yb) of component D relative to nozzle 11b based on an image of component D held by nozzle 11b captured by component recognition camera 13 (imaging unit) during mounting by the component mounting unit 12. The acquired pickup position deviation information (first position deviation information) is stored in the mounting memory unit 21 as pickup deviation information 21d. The acquired pickup position deviation information is also sent to management computer 3 and stored in management memory unit 41 as pickup deviation information 41c.

Now, with reference to Figure 7, we will explain the pickup position deviation information (first position deviation information) of component D relative to nozzle 11b acquired by acquisition unit 22 based on captured image 13a of component D held by nozzle 11b captured by component recognition camera 13 (imaging unit). The captured image 13a displays a center line 13x in the X-axis direction and a center line 13y in the Y-axis direction superimposed on each other. The intersection of center line 13x in the X-axis direction and center line 13y in the Y-axis direction is the center 13c of captured image 13a. During imaging, control is performed so that center 13c of captured image 13a coincides with center Q of nozzle 11b. In other words, center 13c of captured image 13a (center Q of nozzle 11b) is the original pickup target position.

The acquisition unit 22 detects the center Cb of component D from the outline of component D in the captured image 13a. Furthermore, the acquisition unit 22 calculates the pickup position deviation amount Xb in the X-axis direction and the pickup position deviation amount Yb in the Y-axis direction from the positions of the center 13c of the captured image 13a and the center Cb of component D. Hereinafter, the pickup position deviation amount Xb in the X-axis direction and the pickup position deviation amount Yb in the Y-axis direction are referred to as the "pickup position deviation amounts Xb, Yb." The bottom surface Db of component D is captured in the captured image 13a (see FIG. 10(a)). Therefore, the center Cb of component D in the captured image 13a is the center Cb of the bottom surface Db of component D.

In FIG. 5, the mounting control unit 23 controls the tape feeder 8, component mounting unit 12, component recognition camera 13, and head camera 14 to mount component D on the board 6 based on the mounting position and mounting direction included in the mounting data 21a, the correction value included in the correction value information 21b, the correction value suitability information included in the correction suitability information 21c, and the suction position deviation information (first position deviation information) included in the suction deviation information 21d. That is, the component mounting unit 12 corrects the position of the mounting head 11 based on the position of the board 6 imaged by the head camera 14, the suction position deviation information, and the correction value included in the correction value information 21b, and mounts component D on the board 6. In this case, the component mounting unit 12 uses the correction value for component D designated as "suitable" in the suitability information included in the correction suitability information 21c, and does not use the correction value for component D designated as "unsuitable," before mounting component D on the board 6.

In FIG. 5, inspection device M4 includes an inspection control device 30, a board transport mechanism 31, an inspection camera 32, and an inspection camera movement mechanism 33. Inspection control device 30 includes an inspection memory unit 34, an inspection control unit 35, a recognition processing unit 36, a correction value calculation unit 37, and an inspection communication unit 38. The inspection communication unit 38 sends and receives data between component mounting devices M2 and M3 and management computer 3 via communication network 2. Inspection memory unit 34 is a storage device that stores inspection data 34a and the like. Inspection data 34a includes the production model name of the mounted board (board name), the type of component mounted on board 6 (component name), mounting position (XY coordinates), mounting direction (θ direction), defect judgment value, and the like.

The inspection control unit 35 controls the board transport mechanism 31 to transport, position, and hold the mounted board 6 transported from the upstream component mounting device M3 at the inspection position, and then transports the board 6 downstream after the inspection work has been completed. Based on the inspection data 34a, the inspection control unit 35 also controls the inspection camera movement mechanism 33 to move the inspection camera 32 sequentially above the mounting position of the board 6 held at the inspection work position, and causes the inspection camera 32 to capture images of the components D mounted on the board 6.

In FIG. 5, the recognition processing unit 36 recognizes and processes the image captured by the inspection camera 32 to calculate the mounting position deviation amounts ΔX, ΔY, and Δθ (see FIG. 6) of component D mounted on the board 6 from the correct mounting position N. Furthermore, the recognition processing unit 36 determines that the component D is defective when the calculated mounting position deviation amounts ΔX, ΔY, and Δθ exceed the defective judgment value included in the inspection data 34a. Furthermore, the recognition processing unit 36 creates board inspection information 41b for each board 6, including second position deviation information (mounting position deviation amounts ΔX, ΔY, and Δθ) of component D mounted on the board 6 and the pass/fail judgment result for the mounted board, and transmits this to the management computer 3. The management processing device 40 of the management computer 3 stores the received board inspection information 41b in the management memory unit 41.

Now, referring to Figure 6, an example of a method by which the recognition processing unit 36 calculates the mounting position deviation amounts ΔX, ΔY, and Δθ (second position deviation information) of component D mounted on the board 6 from the normal mounting position N will be described. The inspection control unit 35 causes the inspection camera 32 to capture an image of component D mounted on the board 6 at a position where the center of the image capture coincides with the normal mounting position N of component D. The recognition processing unit 36 detects the center C of the mounted component D by performing recognition processing on the captured image.

Then, the recognition processing unit 36 calculates the positional deviation ΔX in the X-axis direction and the positional deviation ΔY in the Y-axis direction from the difference between the center C (ΔX, ΔY) and the mounting position N (0, 0). Furthermore, the recognition processing unit 36 calculates the tilt of the component D in the θ direction as the positional deviation Δθ. The top surface Da of the component D appears in the image captured by the inspection camera 32 (see Figures 10(b) and 10(c)). Therefore, the center C (ΔX, ΔY) recognized by the recognition processing unit 36 is the center C of the top surface Da of the component D.

In FIG. 5, the correction value calculation unit 37 calculates the correction value used by the component mounting devices M2 and M3 when mounting the component D on the board 6, based on the mounting position deviation amounts ΔX, ΔY, and Δθ (second position deviation information) of the component D calculated by the recognition processing unit 36. The correction value calculation unit 37 also creates correction value information including the calculated correction value and transmits it to the component mounting devices M2 and M3. The mounting control device 20 of the component mounting devices M2 and M3 stores the received correction value information in the mounting memory unit 21 as correction value information 21b.

Now, with reference to FIG. 8, we will explain how the correction value calculation unit 37 calculates the correction value ΔCn. First, the correction value calculation unit 37 calculates the average center position Cn (Xn, Yn) of component D from the mounting position deviations ΔX, ΔY, and Δθ of a predetermined number of boards 6 (e.g., 30 boards) included in the board inspection information 41b for the boards 6 on which component D is mounted, without using the correction value ΔCn. The average center position Cn (Xn, Yn) corresponds to the amount of positional deviation caused by factors that cannot be eliminated by correcting the mounting position by taking into account the pickup position deviations Xb, Yb of component D held by nozzle 11b during component mounting and the board position deviation. Therefore, the correction value calculation unit 37 calculates the correction value ΔCn (Xc (Xc = -Xn), Yc (Yc = -Yn)) from the average center position Cn (Xn, Yn) so that the center of component D is aligned with the mounting position N (0, 0) (arrow c).

When calculating the latest correction value ΔCn(Xc, Yc) from the board inspection information 41b for the board 6 using the correction value ΔCn1(Xc1, Yc1), the correction value calculation unit 37 calculates the latest correction value ΔCn(Xc(Xc=Xc1-Xn), Yc(Yc=Yc1-Yn)) from the used correction value ΔCn1(Xc1, Yc1) and the average center position Cn(Xn, Yn) calculated from the board inspection information 41b. In this way, the correction value calculation unit 37 calculates the correction value ΔCn(Xc, Yc) when mounting component D on the board 6 based on the board inspection information 41b that includes at least the second positional deviation information (mounting position deviation amounts ΔX, ΔY, Δθ) of component D mounted on the board 6.

Next, referring to Figure 8, we will explain how the component mounting unit 12 corrects various positional misalignments during mounting. Note that in Figure 8, for simplicity, the positional misalignment of the board position is assumed to be zero. The center Cb of component D held by nozzle 11b during mounting is (Xb, Yb). If the correction value ΔCn is not used, the component mounting unit 12 corrects the position of nozzle 11b by the first correction amount ΔCb1 (-Xb, -Yb) (arrow d) based on the pickup positional misalignment amount Xb, Yb (first positional misalignment information) and mounts component D on the board 6. However, due to factors that cannot be resolved even by correcting the pickup positional misalignment amount Xb, Yb (first positional misalignment information), the center C of component D will be mounted at the average center position Cn (arrow e).

Therefore, to ensure that component D is mounted at the correct mounting position N (0,0), the mounting target position P is set to Xc (-Xn), Yc (-Yn) by moving it (arrow f) from the mounting position N (0,0) by the correction value ΔCn. That is, when the correction value ΔCn is used, the component mounting unit 12 corrects (arrow g) the position of the nozzle 11b by the second correction amount ΔCb2 (-Xb + Xc, -Yb + Yc) based on the pickup position deviation amounts Xb, Yb (first position deviation information) and the correction value ΔCn (Xc, Yc), and mounts component D on the board 6. This ensures that the center C of component D mounted on the board 6 coincides with the correct mounting position N (0,0). In this way, the component mounting unit 12 mounts component D on the board 6 based on the correction value ΔCn.

In FIG. 5, the management processing device 40 of the management computer 3 comprises a management memory unit 41, a judgment unit 42, a setting unit 43, an input unit 44, a display unit 45, and a management communication unit 46. The input unit 44 is an input device such as a keyboard, touch panel, or mouse, and is used to input operation commands and data. The display unit 45 is a display device such as an LCD panel, and displays various information on various screens, such as an operation screen for operation using the input unit 44. The management communication unit 46 is a communication interface, and sends and receives signals and data between the component mounting devices M2 and M3 and the inspection device M4 via the communication network 2.

The management memory unit 41 is a storage device that stores production data 41a, board inspection information 41b, suction deviation information 41c, etc. The production data 41a includes information such as the production model name of the mounted board (board name), the type of component D (component name) to be mounted on the board 6, the size of the component D, the mounting position (XY coordinates), the mounting direction (θ direction), information identifying the component mounting devices M2 and M3 (component mounting unit 12) that mount the component D, the installation position of the tape feeder 8 that supplies the component D, and the installation position of the nozzle 11b.

In FIG. 5, the determination unit 42 determines whether or not to use the correction value ΔCn during mounting based on the adsorption position deviation amounts Xb and Yb in the X-axis direction, which are the adsorption position deviation amounts Xb and Yb (first position deviation information) included in the adsorption position deviation information 41c. Specifically, the determination unit 42 determines whether or not to use the correction value ΔCn based on the degree of deviation of the distribution of data related to the adsorption position deviation amounts Xb and Yb (first position deviation information) from a normal distribution.

Here, with reference to Figures 9(a) to (c), an example of data distribution and the judgment unit 42's judgment on the appropriateness of using the correction value ΔCn will be described. The graphs shown in Figures 9(a) to (c) are examples of histograms representing data related to the amount of adsorption position deviation Xb in the X-axis direction or the amount of adsorption position deviation Yb in the Y-axis direction. The judgment unit 42 judges the appropriateness of using the correction value ΔCn for each of the amount of adsorption position deviation Xb in the X-axis direction and the amount of adsorption position deviation Yb in the Y-axis direction. If both are "appropriate," it is judged that the correction value ΔCn should be used, and if either is "inappropriate," it is judged that the correction value ΔCn should not be used.

Figure 9(a) shows an example in which the data distribution follows a normal distribution G. For example, if the determination unit 42 determines that the data distribution follows a normal distribution G using a method such as a kurtosis test, a skewness test, a Shapiro-Wickle test, or a Kolmogorov-Smirnov test, it determines to use the correction value ΔCn. Furthermore, if the data distribution does not follow a normal distribution, the determination unit 42 determines whether or not to use the correction value ΔCn based on the kurtosis of the data distribution. For example, the determination unit 42 determines to use the correction value ΔCn if the kurtosis of the data distribution is equal to or greater than a predetermined value (e.g., 5). Furthermore, the determination unit 42 may determine whether or not to use the correction value ΔCn based on a combination of the skewness and kurtosis of the data distribution. For example, the determination unit 42 determines to use the correction value ΔCn if the absolute value of the skewness is equal to or less than 1 and the kurtosis is equal to or greater than -0.2.

Figure 9(b) shows an example where kurtosis is equal to or greater than a predetermined value, and Figure 9(c) shows an example where kurtosis is less than the predetermined value. Kurtosis is a numerical value that indicates the degree of peaking of the data distribution or the extent to which the base of the data spreads. In other words, a high kurtosis indicates that the data distribution is peaked (narrow base), while a low kurtosis indicates that the data distribution is not peaked (wide base). Therefore, even if the data distribution does not follow a normal distribution, the judgment unit 42 judges that the correction value ΔCn should be used if the kurtosis of the data distribution is high and the base of the data distribution is narrow.

Now, referring to Figure 10, we will explain an example of component D1 in which the distribution of data related to pickup position deviation amounts Xb, Yb (first position deviation information) may deviate from normal distribution G. Figure 10(a) is a schematic side view of component D1 held by nozzle 11b being imaged by component recognition camera 13. Figure 10(b) is a schematic top view of component D1 mounted on board 6. Figure 10(c) is a schematic side view of component D1 mounted on board 6. Component D1 is a chip component in which the center C of its upper surface Da is misaligned from the center Cb of its lower surface Db. That is, component D1 has a cross-sectional shape of a parallelogram, and the center C of its upper surface Da and the center Cb of its lower surface Db are misaligned in the horizontal direction by an error E.

The pickup position deviation amounts Xb, Yb (first position deviation information) obtained from the image captured by the component recognition camera 13 are obtained from the center Cb of the bottom surface Db of component D1. Furthermore, the mounting position deviation amounts ΔX, ΔY (second position deviation information) obtained from the image captured by the inspection camera 32 are obtained from the center C of the top surface Da of component D1. If component D1, which has a parallelogram cross-sectional shape, is accommodated in the pocket of carrier tape 17 with the sides Dd and Dd oriented irregularly, component D1 will be held by nozzle 11b with the sides Dd and Dd oriented irregularly.

For such components D1, the amount and direction of error E differ for each component D1, resulting in low repeatability of the position of the center Cb of component D1 held by nozzle 11b, and the correction value ΔCn calculated by the correction value calculation unit 37 does not necessarily correct the misalignment during mounting in the correct direction. Therefore, using the correction value ΔCn during mounting may not result in the mounting position misalignment amounts ΔX and ΔY of component D1 converging. Because the error E caused by the shape of component D differs depending on the type of component D and the manufacturer that manufactures component D, the judgment unit 42 judges the appropriateness of using the correction value ΔCn for each type of component D and each manufacturer of component D.

In FIG. 5, the setting unit 43 sets the component mounting unit 12 to use the correction value ΔCn when the judgment unit 42 judges that the use of the correction value ΔCn is appropriate. Furthermore, the setting unit 43 sets the component mounting unit 12 not to use the correction value ΔCn when the judgment unit 42 judges that the use of the correction value ΔCn is inappropriate (inappropriate). Specifically, the setting unit 43 changes (sets) the "appropriate" or "inappropriate" information in the correction appropriateness information 21c stored in the component mounting devices M2 and M3 that mount the component D for which the appropriateness of the correction value ΔCn is to be changed.

As a result, the component mounting units 12 of the component mounting devices M2 and M3 mount the component D on the board 6 using the second correction amount ΔCb2 that uses the correction value ΔCn, or the first correction amount ΔCb1 that does not use the correction value ΔCn, in accordance with the settings of the changed correction suitability information 21c. In other words, the setting unit 43 sets whether or not the correction value ΔCn will be used during mounting by the component mounting units 12.

Next, following the flow chart in Figure 11, we will explain a component mounting method in which component mounting system 1 determines whether or not to use the correction value ΔCn in component mounting devices M2 and M3 based on pickup positional deviation information (first positional deviation information) of component D held by nozzle 11b. First, when production of mounted boards begins in component mounting system 1 (ST1), component mounting devices M2 and M3 perform component mounting work to mount components D on board 6 without using the correction value ΔCn (ST3) until first positional deviation information (pickup positional deviation amounts Xb, Yb) and second positional deviation information (mounting positional deviation amounts ΔX, ΔY) for a predetermined number of boards (e.g., 30 boards) are acquired (No in ST4).

That is, in component mounting devices M2 and M3, the component recognition camera 13 (imaging unit) images the component D held by the nozzle 11b, and first positional deviation information (suction positional deviation amounts Xb and Yb) for a predetermined number of boards is acquired based on the captured image (ST2). Then, the component mounting unit 12 starts mounting components onto the first board and mounts the components D onto the first board using the first correction amount ΔCb1, which does not use the correction value ΔCn, for the predetermined number of boards (ST3).

When the first positional deviation information (adsorption positional deviation amounts Xb, Yb) for a predetermined number of sheets has been acquired (Yes in ST4), the judgment unit 42 analyzes the distribution of data related to the first positional deviation information (ST5: data analysis step). If the analysis result in the data analysis step (ST5) indicates that the data distribution follows a normal distribution (Yes in ST6), or if the data distribution does not follow a normal distribution (No in ST6) but the kurtosis of the data distribution is equal to or greater than a predetermined value (Yes in ST7), the judgment unit 42 determines that the correction value ΔCn should be used (appropriate).

In FIG. 11, the correction value calculation unit 37 then calculates the correction value ΔCn based on the second positional deviation information (mounting positional deviation amounts ΔX, ΔY) for the predetermined number of components acquired in (ST3) (ST8: correction value calculation step). Next, the setting unit 43 sets (changes) the suitability information for component D, which has been judged to be "suitable," to "suitable" in the correction suitability information 21c for component mounting devices M2 and M3 that mount the component D (ST9).

If the analysis results in the data analysis step (ST5) show that the data distribution does not follow a normal distribution (No in ST6) and the kurtosis of the data distribution is less than a predetermined value (No in ST7), the judgment unit 42 judges that the correction value ΔCn should not be used (inappropriate). In this case, the setting unit 43 does not change the suitability information for component D judged to be "inappropriate" in the correction suitability information 21c of component mounting devices M2 and M3 that mount the component D (sets it to "inappropriate"). In this way, the judgment unit 42 judges the suitability of using the correction value ΔCn based on the first positional deviation information (chuck positional deviation amounts Xb and Yb) of a predetermined number of first boards (ST6, ST7).

In FIG. 11, component mounting devices M2 and M3 then perform component mounting work to mount component D on board 6 based on the updated correction suitability information 21c (ST10). That is, for components D judged to be "unsuitable" in (ST6, ST7), component mounting work continues with the first correction amount ΔCb1, which does not use the correction value ΔCn, and for components D judged to be "suitable," component mounting work is performed with the second correction amount ΔCb2, which does use the correction value ΔCn. In this way, the suitability of the correction value ΔCn is judged for each component D according to the degree of repeatability, and an appropriate component mounting method is applied. This makes it possible to achieve good mounting accuracy for a variety of components D mounted on board 6.

If, during component mounting work (ST10), the component D to be mounted on the board 6 is changed to a component D made by another manufacturer, steps (ST2) through (ST9) are executed for that component D. That is, when component D is changed during component mounting on the first board, the determination unit 42 determines whether or not to use the correction value ΔCn based on the first positional deviation information (suction position deviation amounts Xb and Yb) for a predetermined number of changed components D acquired in steps (ST2) through (ST4) for the second time (ST6 and ST7 for the second time). If the determination is "appropriate," the setting unit 43 then sets the appropriateness information for that component D in the correction appropriateness information 21c for the component mounting device M2 or M3 that will mount that component D to "appropriate" (ST9 for the second time).

In this way, the component mounting method of this embodiment captures an image of component D held by nozzle 11b, obtains first positional deviation information (suction positional deviation amounts Xb, Yb) of component D relative to nozzle 11b based on the captured image (ST2), and mounts component D on board 6 based on the first positional deviation information (ST3). Then, based on the first positional deviation information, it is determined whether or not to use correction value ΔCn during mounting (ST6, ST7). If it is determined that correction value ΔCn should be used (Yes in ST6, or No in ST6 and Yes in ST7), correction value ΔCn is calculated based on second positional deviation information of component D mounted on board 6 (ST8). Then, component D is mounted on board 6 based on the first positional deviation information and correction value ΔCn (ST10).

As described above, the component mounting system 1 of this embodiment includes a nozzle 11b that holds a component D, an imaging unit (component recognition camera 13) that images the component D held by the nozzle 11b, an acquisition unit 22 that acquires first positional deviation information (pickup positional deviation amounts Xb, Yb) of the component D relative to the nozzle 11b based on the captured image, a correction value calculation unit 37 that calculates a correction value ΔCn when mounting the component D on the board 6 based on board inspection information 41b that includes at least second positional deviation information (mounting positional deviation amounts ΔX, ΔY) of the component D mounted on the board 6, a component mounting unit 12 that mounts the component D held by the nozzle 11b on the board 6 based on the first positional deviation information and the correction value ΔCn, and a determination unit 42 that determines whether or not to use the correction value ΔCn during mounting based on the first positional deviation information.

This allows the appropriateness of the correction value ΔCn to be determined for each component D according to the degree of repeatability, thereby achieving good mounting accuracy for a variety of components D mounted on the board 6.

In the above embodiment, the inspection device M4 is configured to calculate the correction value ΔCn, but the component mounting system 1 of this embodiment is not limited to this configuration. For example, the management computer 3 may be equipped with a correction value calculation unit 37, which calculates a correction value based on the board inspection information 41b and transmits it to the component mounting devices M2 and M3. Furthermore, the component mounting devices M2 and M3 may each be equipped with a correction value calculation unit 37, which acquires the board inspection information 41b from the inspection device M4 and calculates the correction value ΔCn.

In addition, in the above embodiment, information regarding the appropriateness of using the correction value ΔCn is stored in the mounting memory unit 21 as correction appropriateness information 21c separate from the mounting data 21a, but the storage destination of the information regarding the appropriateness of using the correction value ΔCn is not limited to this configuration. For example, information regarding the appropriateness of using the correction value ΔCn may be stored as information regarding component D in the mounting data 21a, or it may be stored as component data regarding component D separate from the mounting data 21a. Furthermore, the acquired information regarding the appropriateness of using the correction value ΔCn for each component D may be used in component mounting operations on different mounting boards.

The component mounting system and component mounting method of the present invention have the effect of achieving good mounting accuracy for a variety of components mounted on a substrate, and are useful in fields where components are mounted on substrates.

1 Component mounting system 6 Substrate 11b Nozzle 12 Component mounting unit 13 Component recognition camera (imaging unit)
D, D1: Component G: Normal distribution M2, M3: Component mounting device Xb, Yb: Pickup position deviation amount (first position deviation information)
ΔCn: correction value ΔX, ΔY: substrate positional deviation amount (second positional deviation information)

Claims (9)

a nozzle for holding the part;
an imaging unit that images the component held by the nozzle;
an acquisition unit that acquires first positional deviation information of the component with respect to the nozzle based on the captured image;
a correction value calculation unit that calculates a correction value when mounting the component on the board based on board inspection information that includes at least second positional deviation information of the component mounted on the board;
a component mounting unit that mounts the component held by the nozzle onto a board based on the first positional deviation information and the correction value;
a determination unit that determines whether or not to use the correction value during mounting based on the first positional deviation information ,
The determination unit determines that the correction value should be used if the distribution of data related to the first positional deviation information follows a normal distribution . a nozzle for holding the part;
an imaging unit that images the component held by the nozzle;
an acquisition unit that acquires first positional deviation information of the component with respect to the nozzle based on the captured image;
a correction value calculation unit that calculates a correction value when mounting the component on the board based on board inspection information that includes at least second positional deviation information of the component mounted on the board;
a component mounting unit that mounts the component held by the nozzle onto a board based on the first positional deviation information and the correction value;
a determination unit that determines whether or not to use the correction value during mounting based on the first positional deviation information,
When the distribution of data relating to the first positional deviation information does not follow a normal distribution, the determination unit determines whether or not to use the correction value based on the kurtosis of the data. The component mounting system according to claim 2 , wherein the determining unit determines that the correction value should be used when the kurtosis of the distribution of the data is equal to or greater than a predetermined value. The component mounting system according to claim 1 , wherein the determining unit determines whether or not use of the correction value is appropriate for each type of component. The component mounting system according to claim 1 , wherein the determining unit determines whether or not use of the correction value is appropriate for each type of component and each manufacturer of the component. the component mounting unit starts mounting components onto a first board and mounts the components onto the first board without using the correction value up to a predetermined number of boards;
The component mounting system according to claim 1 , wherein the determining unit determines whether or not use of the correction value is appropriate based on the first misalignment information for the predetermined number of sheets. If a component is changed during component mounting on the first board,
The component mounting system according to claim 1 , wherein the determining unit determines whether or not to use the correction value based on the first positional deviation information for a predetermined number of the components after the component is changed. An image of the part held by the nozzle is taken.
acquiring first positional deviation information of the component relative to the nozzle based on the captured image;
Mounting the component on a board based on the first positional deviation information;
determining whether or not to use a correction value during mounting based on the first positional deviation information;
If it is determined that the correction value is to be used, the correction value is calculated based on second positional deviation information of the component mounted on the board;
Then, the component is mounted on the board based on the first positional deviation information and the correction value ;
In determining whether or not to use the correction value, if the distribution of data related to the first positional deviation information follows a normal distribution, it is determined that the correction value should be used . An image of the part held by the nozzle is taken.
acquiring first positional deviation information of the component relative to the nozzle based on the captured image;
Mounting the component on a board based on the first positional deviation information;
determining whether or not to use a correction value during mounting based on the first positional deviation information;
If it is determined that the correction value is to be used, the correction value is calculated based on second positional deviation information of the component mounted on the board;
Then, the component is mounted on the board based on the first positional deviation information and the correction value;
A component mounting method in which, in determining whether or not to use the correction value, if the distribution of data related to the first positional deviation information does not follow a normal distribution, the appropriateness of using the correction value is determined based on the kurtosis of the data.