Offset value calculation system, offset value calculation method, and component mounting device

Abstract

To provide an offset value calculation system capable of precisely calculating an offset value of a mounting head, an offset value calculation method, and a component mounting device.SOLUTION: The offset value calculation method includes the steps of: acquiring first data regarding the state of a component mounted by multiple component mounting units based on a first offset value (ST2); calculating a second offset value based on the first data (ST3); acquiring second data based on the second offset value (ST4); calculating mounting accuracy based on the second data (ST5); when determined that the mounting accuracy is not proper (No in ST6); selecting an improper component mounting unit in which the second offset value is improper based on the second data (ST7); acquiring third data of the component mounted by the improper component mounting unit based on the second offset value(ST8); and calculating a third offset value of the improper component mounting unit based on at least the third data (ST9).SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to an offset value calculation system and method for calculating an offset value used in a component mounting device, and the component mounting device. [Background technology]

[0002] A component mounting device mounts components held by nozzles onto a board to produce a mounted board. In order to reduce misalignment of components to be mounted on the board and improve mounting accuracy, the component mounting device performs calibration to measure in advance offset values ​​that cancel out distortions in each part of the device, and controls each part based on the offset values ​​to mount the components on the board. The system of Patent Document 1 places calibration components held by a head having multiple nozzles on a component mounting accuracy measuring unit, and performs calibration to measure the amount of misalignment of the mounting position from an image captured by a camera from above. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-50335 A Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, after measuring an offset value, the accuracy of the mounting position for mounting a component on a board is verified based on this offset value, and if the accuracy is not achieved, the offset value to be used in production is determined by repeating the process of measuring the offset value and the process of verifying the accuracy until the predetermined accuracy is reached. However, measuring the offset value takes time, and there is room for further improvement in order to obtain an appropriate offset value in a short time.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide an offset value calculation system, an offset value calculation method, and a component mounting apparatus that are capable of properly calculating the offset value of a mounting head. [Means for solving the problem]

[0006] The offset value calculation system of the present invention comprises a data acquisition means for using a plurality of component mounting units, each having a component holder for holding the components, to remove components from a component supply unit and mount them on a board, and for acquiring data regarding the state of the components mounted on the board; a mounting accuracy calculation unit for calculating the mounting accuracy of the plurality of component mounting units based on the data acquired by the data acquisition means; a judgment unit for determining whether the calculated mounting accuracy is appropriate; an offset value calculation unit for calculating offset values ​​of the plurality of component mounting units based on the data acquired by the data acquisition means; and a selection unit for selecting an improper component mounting unit among the plurality of component mounting units, which is a component mounting unit whose offset value is not appropriate, based on the data acquired by the data acquisition means.When the judgment unit determines that the mounting accuracy is not appropriate, the data acquisition means re-acquires data for the improper component mounting unit, and the offset value calculation unit re-calculates the offset value of the improper component mounting unit based on the re-acquired data.

[0007] The offset value calculation method of the present invention is a method for calculating offset values ​​of component mounting units each having a component holder for holding components, and which takes components from a component supply unit and mounts them on a board, the method including a first data acquisition step of mounting components onto the board by a plurality of component mounting units based on a first offset value and acquiring first data relating to the states of the components mounted on the board, a second offset value calculation step of calculating second offset values ​​for each of the plurality of component mounting units based on the first data, and a second data acquisition step of mounting components onto the board by the plurality of component mounting units based on the second offset value and acquiring second data relating to the states of the components mounted on the board. a mounting accuracy calculation step of calculating the mounting accuracy of a plurality of the component mounting portions based on the second data; a judgment step of judging whether the calculated mounting accuracy is appropriate; a selection step of selecting, based on the second data, an improper component mounting portion which is a component mounting portion having an improper second offset value if it is judged in the judgment step that the mounting accuracy is not appropriate; a third data acquisition step of mounting components onto a board by the improper component mounting portion based on the second offset value, and acquiring third data relating to a state of the components mounted on the board; and a third offset value calculation step of calculating a third offset value of the improper component mounting portion based on at least the third data.

[0008] The component mounting device of the present invention includes a component supplying unit that supplies components, a plurality of component mounting units each having a component holder that holds components, and that removes components from the component supplying unit and mounts them on a board, a control unit that controls the component supplying unit and the plurality of component mounting units to mount components on the board based on offset values ​​of the plurality of component mounting units, an imaging unit that images the components mounted on the board, a data extraction unit that extracts data relating to the states of the components mounted on the board from the imaging results by the imaging unit, a mounting accuracy calculation unit that calculates the mounting accuracy of the plurality of component mounting units based on the data extracted by the data extraction unit, a determination unit that determines whether the calculated mounting accuracy is appropriate, and a data extraction unit that performs a data extraction on the data extracted by the data extraction unit. and a selection unit that selects, from the plurality of component mounting units, an improper component mounting unit which is a component mounting unit having an improper offset value based on the data extracted by the data extraction unit. When the determination unit determines that the mounting accuracy is improper, the control unit causes the improper component mounting unit to mount a component on the board, the data extraction unit re-extracts data relating to a state of the component mounted on the board by the improper component mounting unit from the imaging result by the imaging unit, and the offset value calculation unit recalculates the offset value of the improper component mounting unit based also on the re-extracted data. Effect of the Invention

[0009] According to the present invention, the offset value to be erased by the mounting head can be calculated appropriately. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a configuration explanatory diagram of a component mounting system according to an embodiment of the present invention; [Diagram 2] FIG. 1 is a configuration explanatory diagram of a component mounting device according to an embodiment of the present invention; [Diagram 3] FIG. 2A is a plan view of a mounting head provided in a component mounting device according to an embodiment of the present invention; [Figure 4]FIG. 2 is a block diagram showing the configuration of a control system of the component mounting apparatus according to the embodiment of the present invention. [Diagram 5] FIG. 2 is an explanatory diagram of a board on which components are mounted by a component mounting device according to an embodiment of the present invention; [Figure 6] FIG. 2 is an explanatory diagram of data relating to the state of a component acquired by a component mounting device according to an embodiment of the present invention; [Figure 7] (a) (b) (c) (d) are explanatory diagrams for determining whether an offset value based on a deviation in a component mounting device according to an embodiment of the present invention is appropriate. [Figure 8] (a) (b) (c) (d) are diagrams for explaining a judgment as to whether an offset value based on variation in a component mounting device according to an embodiment of the present invention is appropriate. [Figure 9] FIG. 1 is a flow diagram of an offset value calculation method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] An embodiment of the present invention will be described in detail below with reference to the drawings. The configurations, shapes, etc. described below are examples for explanation, and can be appropriately changed according to the specifications of the component mounting system, the component mounting device, the mounting head, the management computer, and the inspection device. In the following, the same reference numerals are used for corresponding elements in all the drawings, and duplicated explanations are omitted. In FIG. 2 and some parts described later, the X-axis (perpendicular to the paper surface in FIG. 2) in the board transport direction and the Y-axis (left-right direction in FIG. 2) perpendicular to the board transport direction are shown as two axes perpendicular to each other in the horizontal plane. In FIG. 2 and some parts described later, the Z-axis (up-down direction in FIG. 2) is shown as the height direction perpendicular to the horizontal plane. In FIG. 3(b) and some parts described later, the θ-direction is shown as the direction of rotation about the Z-axis as the rotation axis.

[0012] First, the configuration of component mounting system 1 will be described with reference to Fig. 1. Component mounting system 1 includes component mounting device M1 and inspection device M2, and has the function of mounting components on a board to produce a mounted board. These devices are connected to management computer 3 via communication network 2. Note that the number of component mounting devices M1 included in component mounting system 1 is not limited to one, and may be two or more.

[0013] The component mounting device M1 performs a component mounting operation in which a component taken out from a component supply unit is mounted at a mounting position on a board carried in from upstream by a component mounting unit equipped in the mounting head. The inspection device M2 uses an inspection camera to inspect the condition of the component, such as the mounting position of the component mounted on the board transported from the component mounting device M1. In addition to the line management function, the management computer 3 has a function to calculate an offset value that cancels out the distortion of the component mounting unit equipped in the component mounting device M1 based on data acquired by the component mounting device M1 or the inspection device M2.

[0014] Next, the configuration of the component mounting device M1 will be described with reference to FIG. 2. The component mounting device M1 has a function of mounting a component D on a board B. A board transport mechanism 5 provided on the upper surface of a base 4 transports, positions, and holds the board B along the X-axis. A head moving mechanism 6 provided above the base 4 moves a mounting head 7, which is detachably attached via a plate 6a, in horizontal directions (X-axis direction and Y-axis direction). The mounting head 7 has a plurality of component mounting units 8 that can lift and lower while suction-holding the component D. A nozzle 9 that suctions and holds the component D is detachably attached to the lower end of each of the component mounting units 8. In other words, the nozzle 9 is a component holder that holds the component D.

[0015] A plurality of tape feeders 10 are mounted in a line along the X-axis on feeder base 11a on the upper part of dolly 11, which is coupled to base 4 on the side of board transport mechanism 5. Carrier tape 12, which stores components D to be supplied to component mounting device M1, is wound and stored on reel 13 and held on dolly 11. Carrier tape 12 inserted into tape feeder 10 is pitch-fed, and components D stored on carrier tape 12 are sequentially supplied to component supply position 10a provided above tape feeder 10. In other words, tape feeder 10 is a component supply unit that supplies components D.

[0016] 2, in the component mounting operation, the multiple component mounting units 8 of the mounting head 7 are moved above the tape feeder 10 by the head moving mechanism 6, and pick up the component D supplied to the component supply position 10a of the tape feeder 10 by vacuum suction with the nozzle 9. The mounting head 7 holding the component D is moved above the board B held by the board transport mechanism 5 by the head moving mechanism 6, and mounts the component D at a predetermined mounting position on the board B. In this way, the multiple component mounting units 8 each have a component holder (nozzle 9) that holds the component D, and picks up the component D from the component supply unit (tape feeder 10) and mounts it on the board B.

[0017] 2, a head camera 14 with its optical axis facing in the negative direction (downward) of the Z axis is attached to plate 6a. Head camera 14 moves integrally with mounting head 7 in the positive and negative directions of the X axis and the positive and negative directions of the Y axis by head movement mechanism 6. As mounting head 7 moves, head camera 14 moves above board B positioned by board transport mechanism 5, and captures images of board marks (not shown) provided on board B and components D mounted on board B. In other words, head camera 14 is an imaging unit that captures images of components D mounted on board B.

[0018] A component recognition camera 15 with its optical axis facing in the positive direction (upward) of the Z axis is attached to the upper surface of the base 4 between the board transport mechanism 5 and the tape feeder 10. The component recognition camera 15 captures an image of the component D held by the nozzle 9 when the nozzle 9 that picked up the component D passes above. From the image captured by the component recognition camera 15, the position of the picked-up component D relative to the nozzle 9 is detected. When the mounting head 7 mounts the component on the board B, the mounting position is corrected taking into account the image captured by the component recognition camera 15 of the component D and the image captured by the head camera 14 of the board position.

[0019] Next, the configuration of the mounting head 7 will be described with reference to FIG. 3(a) and FIG. 3(b). The mounting head 7, which is detachable from the plate 6a, is provided with a plurality of component mounting sections 8(j). In this example, the mounting head 7 is provided with eight component mounting sections 8(j) aligned along the X-axis in two rows along the Y-axis. That is, the mounting head 7 is provided with 16 component mounting sections 8(1) to 8(16). Each component mounting section 8(j) is provided with a driving mechanism. By driving the driving mechanism, each component mounting section 8(j) raises and lowers the nozzle 9 attached to the lower end (arrow a), and rotates the nozzle 9 in the θ direction around the nozzle axis AN (axis core) as the rotation axis (arrow b). In this way, the plurality of component mounting sections 8(j) can rotate the component D around the axis (nozzle axis AN) to mount it on the board B.

[0020] Next, referring to Fig. 4, the configuration of the control system of the component mounting device M1 will be described, focusing on the function of calculating offset values ​​of the multiple component mounting units 8(j) of the mounting head 7. The component mounting device M1 includes a control device 20, a board transport mechanism 5, a head moving mechanism 6, a mounting head 7, a tape feeder 10, a head camera 14, and a component recognition camera 15. The mounting head 7 includes a head memory unit 7a and multiple component mounting units 8(j). The head memory unit 7a is a non-volatile memory device, and stores offset values ​​that cancel distortions such as the inclination of the axis (nozzle axis AN) of the multiple component mounting units 8(j) of the mounting head 7. The offset values ​​of the head memory unit 7a are calculated and updated during shipping inspection of the mounting head 7 or during calibration after mounting on the component mounting device M1.

[0021] The control device 20 includes a storage unit 21, a placement control unit 22, a data acquisition processing unit 23, a data extraction unit 24, an offset value calculation unit 25, a placement accuracy calculation unit 26, a judgment unit 27, a first selection unit 28, a second selection unit 29, and an update unit 30. The storage unit 21 is a storage device, and stores placement data 31, acquisition data 32, offset value data 33, and the like. In the placement data 31, various information such as the type of component D to be mounted on the board B and the coordinates of the placement position on the board B is stored for each type of mounting board. The placement control unit 22 reads out the offset value (first offset value) stored in the head storage unit 7a of the placement head 7 and stores it in the offset value data 33 when the placement head 7 is mounted on the component placement device M1 or when the component placement device M1 is started.

[0022] 4, based on placement data 31 and offset value data 33 (first offset value), placement control unit 22 executes a component placement operation in which nozzle 9 (component holder) attached to component placement unit 8(j) of placement head 7 picks up component D supplied by tape feeder 10 (component supply unit) and places it at a placement position on board B. For example, when nozzle 9 attached to component placement unit 8(1) picks up component D from tape feeder 10 and places component D on board B, placement control unit 22 controls head movement mechanism 6 based on the offset value of component placement unit 8(1) included in offset value data 33 to correct the stop position and rotation angle of nozzle 9.

[0023] The data acquisition processing unit 23 controls the head moving mechanism 6, the component mounting unit 8(j) of the mounting head 7, the tape feeder 10, and the head camera 14 to mount the component D on the board B and execute a data acquisition process to acquire data relating to the state of the mounted component D. The data extraction unit 24 processes the captured image of the component D mounted on the board B by the head camera 14, and extracts the mounting position deviation amounts, which are deviations in the X-axis direction, Y-axis direction, and θ direction of the mounting position of the actually mounted component D from the position where it should be mounted on the board B. That is, the data extraction unit 24 extracts data (mounting position deviation amounts) relating to the state of the component D mounted on the board B from the imaging results by the head camera 14 (imaging unit).

[0024] In the data acquisition process, first, the data acquisition processor 23 rotates the nozzle 9 mounted on the component mounting unit 8(j) by a predetermined rotation angle based on the offset value in the θ direction. Next, the data acquisition processor 23 moves the component mounting unit 8(j) based on the offset value in the X-axis direction and the offset value in the Y-axis direction, and causes the component D to be taken out of the tape feeder 10 and mounted on the board B. Next, the data acquisition processor 23 causes the head camera 14 to capture an image of the component D mounted on the board B. Next, the data extraction unit 24 extracts the amount of mounting position deviation from the captured image.

[0025] That is, data acquisition processing unit 23, data extraction unit 24, head moving mechanism 6, component mounting unit 8(j), and head camera 14 (imaging unit) constitute data acquisition means 34 that extracts components D from tape feeder 10 (component supply unit) by multiple component mounting units 8(j), each having a nozzle 9 (component holder), and mounts them on board B, and acquires data (amount of mounting position deviation) regarding the state of components D mounted on board B. Data acquisition processing unit 23 is also a control unit that controls tape feeder 10 and multiple component mounting units 8(j), and mounts components D on board B based on the offset values ​​of the multiple component mounting units 8(j).

[0026] Here, referring to FIG. 5, an example of the board B on which the components D are mounted by the data acquisition means 34 including the mounting head 7 shown in FIG. 3 will be described. In this example, the nozzle 9 is rotated by each of the component mounting units 8(1)-8(16) at rotation angles of "0°", "90°", "180°", and "270°", and the components D are taken out of the tape feeder 10 three times each and mounted at mounting positions set at equal intervals on the board B. That is, the data acquisition process 23 (control unit) rotates the nozzle 9 (component holder) by the multiple component mounting units 8(1)-8(16) at multiple (four) different predetermined rotation angles, and the components D are taken out of the tape feeder 10 (component supply unit) and mounted on the board B. Note that the number of components D mounted under the same conditions is not limited to three, and may be changed according to the purpose.

[0027] Next, an example of the mounting position misalignment amount (Xd, Yd, θd) extracted by the data extraction unit 24 (data acquisition means 34) will be described with reference to Fig. 6. The captured image 40 shown in Fig. 6 is captured by the head camera 14 that has moved so that the center 40c of the imaging field of view is located at a mounting position on the board B that has been set in advance for the component D mounted on the board B. In other words, the center 40c of the imaging field of view is the mounting position on the board B where the component D is to be mounted.

[0028] The data extraction unit 24 recognizes and processes the captured image 40 to extract the mounting position misalignment amount Xd in the X-axis direction, the mounting position misalignment amount Yd in the Y-axis direction, and the mounting position misalignment amount θd in the θ direction of the component D of the center Cd of the component D. That is, the data extraction unit 24 extracts the mounting position misalignment amount Xd in the X-axis direction and the mounting position misalignment amount Yd in the Y-axis direction based on the position of the center Cd of the component D from the center 40c of the imaging field of view. The data extraction unit 24 also extracts the mounting position misalignment amount θd in the θ direction from the inclination of the outer shape of the component D. The extracted mounting position misalignment amount (Xd, Yd, θd) is stored in the storage unit 21 as the acquired data 32. In this way, the data extraction unit 24 extracts data (mounting position misalignment amount (Xd, Yd, θd)) related to the state of the component D mounted on the board B from the imaging result by the head camera 14 (imaging unit).

[0029] 4, the offset value calculation unit 25 calculates offset values ​​for each of the component mounting units 8(1)-8(16) based on the data (mounting position misalignment amount (Xd, Yd, θd)) extracted by the data extraction unit 24. The offset value calculation unit 25 calculates offset values ​​in the X-axis direction, the Y-axis direction, and the θ direction for each component mounting unit 8(1)-8(16) and for each rotation angle of the nozzle 9.

[0030] In the example of FIG. 5, the offset value calculation unit 25 calculates the average of the mounting position misalignment amounts Xd in the X-axis direction of three components D mounted on the board B by the component mounting unit 8(1) by rotating the nozzle 9 to a rotation angle of “0°” as the X-axis offset value Xs, the average of the mounting position misalignment amounts Yd in the Y-axis direction as the Y-axis offset value Ys, and the average of the mounting position misalignment amounts θd in the θ direction as the θ-direction offset value θs.

[0031] Hereinafter, the offset value at a rotation angle of "0°" of component mounting unit 8(1) will be indicated as offset value (1:0°). Similarly, based on the mounting position deviation amount (Xd, Yd, θd) (data) of component D mounted by component mounting unit 8(1) acquired by data acquisition means 34, offset value calculation unit 25 calculates offset value (1:90°), offset value (1:180°), and offset value (1:270°). The calculated offset values ​​are stored in memory unit 21 as offset value data 33.

[0032] 4, the placement accuracy calculation unit 26 calculates the placement accuracy of the placement head 7 having the multiple component placement units 8(1)-8(16) based on all placement position misalignment amounts (Xd, Yd, θd) (data) of the components D placed by the component placement units 8(1)-8(16) with their rotation angles changed, extracted by the data extraction unit 24 and stored in the acquired data 32. For example, the placement accuracy calculation unit 26 calculates, as the placement accuracy, a process capability index Cpk where the variation (standard deviation) of the placement position misalignment amounts (Xd, Yd, θd) falls within a range of +30 μm or -30 μm from the target placement position (a range from an estimated value of the population mean to an upper or lower standard limit). The placement accuracy may be the process capability index Cp or another index.

[0033] The determination unit 27 determines whether the mounting accuracy calculated by the mounting accuracy calculation unit 26 is appropriate. For example, the determination unit 27 determines that the mounting accuracy is appropriate when the calculated process capability index Cpk is equal to or greater than a predetermined judgment reference value. The first selection unit 28 and the second selection unit 29 each determine whether the offset values ​​of the component mounting units 8(1)-8(16) are appropriate based on the accuracy verification data for each rotation angle acquired by the data acquisition means 34 (data extracted by the data extraction unit 24), and select the component mounting units having inappropriate offset values ​​from among the multiple component mounting units 8(1)-8(16) as "inappropriate component mounting units."

[0034] Here, a method for selecting an inappropriate component mounting portion by the first selection unit 28 will be described with reference to Fig. 7. Fig. 7(a) shows mounting position deviation amounts (Xd, Yd, θd) extracted from the imaging results of five components D for accuracy verification mounted on the board B by the component mounting unit 8(1) with the nozzle 9 rotated by "0°" based on the offset value (1:0°) calculated by the offset value calculation unit 25 by the data acquisition means 34. The mounting position deviation amount Xd in the X-axis direction and the mounting position deviation amount Yd in the Y-axis direction are plotted as a scatter diagram of orthogonal coordinates. The mounting position deviation amount θd in the θ direction is plotted on a one-dimensional graph.

[0035] Similarly, Fig. 7(b) shows the mounting position misalignment amounts (Xd, Yd, θd) of five components D for accuracy verification when the rotation angle by component mounting unit 8(1) is "90°", Fig. 7(c) shows "180°", and Fig. 7(d) shows "270°". The first selection unit 28 determines that the calculated offset value is appropriate when the average value of the mounting position misalignment amounts Xd in the X-axis direction, the average value of the mounting position misalignment amounts Yd in the Y-axis direction, and the average value of the mounting position misalignment amounts θd in the θ direction are each within a predetermined range.

[0036] 7(a) to 7(d), the average value of the mounting position misalignment amount Xd in the X-axis direction and the average value of the mounting position misalignment amount Yd in the Y-axis direction are plotted with "x" in the scatter diagram on the left. The average value of the mounting position misalignment amount θd in the θ-direction is plotted with "x" in the one-dimensional graph on the right. The first selection unit 28 determines that the calculated offset value is appropriate when the deviation (√(Xd^2+Yd^2)) of the average mounting position misalignment amount (Xd, Yd) in the X-axis direction and the Y-axis direction from the origin is smaller than the judgment distance Ra and the deviation of the average mounting position misalignment amount θd in the θ-direction from the origin is within the range of -θa to +θa.

[0037] In the example of FIG. 7(a), the X-axis direction and the Y-axis direction are appropriate because the average value indicated by "x" is inside the circle whose radius is the judgment distance Ra. On the other hand, the θ direction is inappropriate because the average value indicated by "x" is outside (outside the range) of +θa. Therefore, the first selection unit 28 judges the calculated offset value (1:0°) to be inappropriate (x). In the example of FIG. 7(b), the θ direction is appropriate because the average value is within the range from -θa to +θa. On the other hand, the X-axis direction and the Y-axis direction are inappropriate because the average value is outside the circle whose radius is the judgment distance Ra. Therefore, the first selection unit 28 judges the calculated offset value (1:90°) to be inappropriate (x).

[0038] In the example of Fig. 7(c), the average values ​​in the X-axis direction and the Y-axis direction are inside a circle with a radius equal to the judgment distance Ra, and the average value in the θ direction is also within the range of -θa to +θa. Therefore, the first selection unit 28 judges that the calculated offset value (1:180°) is appropriate (◯). Similarly, in the example of Fig. 7(d), the first selection unit 28 judges that the calculated offset value (1:270°) is appropriate (◯). Then, the first selection unit 28 determines that the offset values ​​of the rotation angles "0°" and "90°" of the component mounting unit 8(1) are not appropriate, and selects the component mounting unit 8(1) as an inappropriate component mounting unit.

[0039] In this way, first selection unit 28 determines whether the offset value for each rotation angle is appropriate based on the deviation (average value of mounting position deviation) of the mounting position of component D for accuracy verification mounted on board B from the position where component D should be mounted, and selects an improper component mounting portion. Note that first selection unit 28 may determine that the calculated offset value is appropriate when the average values ​​of mounting position deviation Xd in the X-axis direction and mounting position deviation Yd in the Y-axis direction are within the range from -Ra to +Ra.

[0040] Next, a method for selecting an improper component mounting portion by the second selection unit 29 will be described with reference to Fig. 8. The mounting position misalignment amounts (Xd, Yd, θd) plotted in the scatter diagrams and one-dimensional graphs shown in Fig. 8(a) to Fig. 8(d) are the same as those in Fig. 7(a) to Fig. 7(d). The second judgment processing unit 26b judges that the calculated offset value is proper when the ranges (differences between maximum and minimum values) of the five mounting position misalignment amounts Xd in the X-axis direction, the ranges of the five mounting position misalignment amounts Yd in the Y-axis direction, and the ranges of the five mounting position misalignment amounts θd in the θ direction are each within a predetermined range.

[0041] In the example of FIG. 8(a), the offset values ​​are appropriate in the X-axis and Y-axis directions because all of the five mounting position misalignment amounts (Xd, Yd) indicated by "o" are inside the square of the judgment range Rb (the range is smaller than the judgment range Rb). Also, the offset values ​​are appropriate in the θ direction because all of the five mounting position misalignment amounts θd are inside the width θb (the range is smaller than the width θb). Therefore, the second selection unit 29 judges that the calculated offset value (1:0°) is appropriate (o). Similarly, in the example of FIG. 8(b), the second judgment processing unit 26b judges that the calculated offset value (1:90°) is appropriate (o).

[0042] In the example of FIG. 8(c), all five mounting position misalignment amounts (Xd, Yd) are inside the square of the judgment range Rb in the X-axis direction and the Y-axis direction. On the other hand, all of the mounting position misalignment amounts θd in the θ direction do not fall within the width θb. Therefore, the second selection unit 29 judges that the calculated offset value (1:180°) is inappropriate (×). In the example of FIG. 8(d), all five mounting position misalignment amounts θd in the θ direction are inside the width θb. On the other hand, all of the five mounting position misalignment amounts (Xd, Yd) do not fall within the square of the judgment range Rb. Therefore, the second selection unit 29 judges that the calculated offset value (1:270°) is inappropriate (×).

[0043] Then, the second selection unit 29 determines that the offset values ​​of the rotation angles "180°" and "270°" of the component mounting unit 8(1) are not appropriate, and selects the component mounting unit 8(1) as an inappropriate component mounting unit. In this manner, the second selection unit 29 determines whether the offset value for each rotation angle is appropriate based on the variation (range) of the data (amount of mounting position misalignment), and selects the inappropriate component mounting unit. Note that, as an embodiment, the component mounting units 8(1)-8(16) whose offset values ​​are determined to be inappropriate by either the first selection unit 28 or the second selection unit 29 may be selected as the inappropriate component mounting unit.

[0044] In Fig. 4, when the determination unit 27 determines that the mounting accuracy of the mounting head 7 is inappropriate, the data acquisition means 34 reacquires data (amount of mounting position misalignment) only at the rotation angle for which the offset value is determined to be inappropriate by the inappropriate component mounting unit selected by the first selection unit 28 or the second selection unit 29. Then, the offset value calculation unit 25 recalculates the offset value for the rotation angle for the inappropriate component mounting unit that is determined to be inappropriate based on the reacquired data. In the example of Fig. 7, the offset value (1:0°) and the offset value (1:90°) are recalculated.

[0045] When recalculating the offset value of the improper component mounting portion, offset value calculation unit 25 may recalculate the offset value by adding at least one of the initially acquired data and the data acquired for accuracy verification to the reacquired data. That is, the offset value may be recalculated as the average value of converted data obtained by subtracting the offset value used by data acquisition means 34 when mounting on board B from the acquired data (amount of mounting position misalignment). By increasing the number of data used for calculation, it is possible to remove (reduce) random components such as the variation in the position where tape feeder 10 supplies components D.

[0046] 4, when the determination unit 27 determines that the mounting accuracy of the mounting head 7 is appropriate, the update unit 30 updates the offset value (first offset value) stored in the head memory unit 7a to the offset value calculated by the offset value calculation unit 25. Note that, as long as the mounting accuracy of the mounting head 7 is appropriate, it does not matter if the variation in the mounting position of the component D by at least one component mounting unit 8(j) among the component mounting units 8(1) to 8(16) is larger than the variation in the mounting position of the component D by the other component mounting units 8(j).

[0047] 9, a method for calculating an offset value for a component mounting unit 8(j) that takes out a component D from a tape feeder 10 (component supply unit) in component mounting device M1 and mounts it on board B will be described. First, mounting control unit 22 reads out the offset value (first offset value) stored in head memory unit 7a, and stores it in memory unit 21 as offset value data 33 (ST1: first offset value reading step).

[0048] Next, based on the first offset value stored in memory unit 21, data acquisition means 34 rotates nozzle 9 (component holder) by multiple component mounting units 8(j) at multiple different rotation angles, removes component D from tape feeder 10 and mounts it on board B (see Figure 5), and acquires first data (amount of mounting position deviation) regarding the state of component D mounted on board B (ST2: first data acquisition step).

[0049] 9, offset value calculation unit 25 then calculates second offset values ​​for each of the component mounting units 8(j) for each rotation angle based on the first data (ST3: second offset value calculation step). Next, data acquisition means 34 rotates nozzle 9 to multiple different rotation angles by the component mounting units 8(j) based on the second offset values, removes components D from tape feeder 10, and mounts them on board B, and acquires second data (amount of mounting position misalignment) for verifying accuracy regarding the state of components D mounted on board B (ST4: second data acquisition step).

[0050] Next, mounting accuracy calculation unit 26 calculates the mounting accuracy (such as process capability index Cpk) of mounting head 7 (as a whole of multiple component mounting units 8(j)) based on the second data (ST5: mounting accuracy calculation step). Next, judgment unit 27 judges whether the calculated mounting accuracy is appropriate (ST6: judgment step). For example, in the judgment step (ST6), it is judged whether the process capability index Cpk is equal to or greater than a predetermined judgment reference value. If it is judged that the mounting accuracy is not appropriate (No in ST6), first selection unit 28 or second selection unit 29 selects an inappropriate component mounting unit having an inappropriate second offset value based on the second data (ST7: selection step).

[0051] In the selection step (ST7), first selection unit 28 determines whether the second offset value is appropriate for each rotation angle based on the deviation of the mounting position of component D mounted on board B from the position where component D should be mounted (average value of mounting position deviation amount), and selects an improper component mounting portion (see FIG. 7). Alternatively, in the selection step (ST7), second selection unit 29 determines whether the second offset value is appropriate for each rotation angle based on the variation in the second data (range of mounting position deviation amount), and selects an improper component mounting portion (see FIG. 8).

[0052] 9, when an improper component mounting unit is selected in the selection step (ST7), the data acquisition means 34 mounts the component D on the board B at the rotation angle at which the improper component mounting unit judges the second offset value to be improper, based on the second offset value, and acquires third data (amount of mounting position deviation) relating to the state of the component D mounted on the board B (ST8: third data acquisition step). That is, in the selection step (ST7), the improper component mounting unit is selected by judging whether the second offset value is appropriate based on the second data for each rotation angle, and in the third data acquisition step (ST8), third data for the rotation angle at which the improper component mounting unit judges the second offset value to be improper is acquired.

[0053] Next, based on the third data, offset value calculation unit 25 calculates a third offset value of the rotation angle at which the second offset value of the improper component mounting unit is determined to be improper (ST9: third offset value calculation step). Note that offset value calculation unit 25 may calculate the third offset value by adding the first data or the second data to the third data. Next, based on the third offset value, data acquisition means 34 removes component D from tape feeder 10 and mounts it on board B at the rotation angle at which the second offset value is determined to be improper by the improper component mounting unit, and acquires fourth data (amount of mounting position deviation) for verifying accuracy regarding the state of component D mounted on board B (ST10: fourth data acquisition step).

[0054] In FIG. 9, the process returns to the placement accuracy calculation step (ST5), where the placement accuracy of the multiple component mounting units 8(j) (mounting heads 7) is calculated based on the second data and the fourth data. In addition, in the calculation of the placement accuracy, data (placement position deviation amount) of the rotation angle for which the second offset value of the improper component mounting unit is determined to be improper from the second data may be excluded. This makes it possible to exclude accidental outliers contained in the second data acquired in the second data acquisition step (ST4). In this case, the placement accuracy is calculated from the placement position deviation amount of the proper rotation angle of the component mounting unit 8(j) already acquired with the second offset value and the placement position deviation amount of the improper rotation angle of the improper component mounting unit reacquired with the third offset value.

[0055] Next, a determination step (ST6) is performed to determine whether the mounting accuracy based on the third offset value is appropriate. If it is determined that the mounting accuracy of the mounting head 7 is not appropriate (No in ST6), the selection step (ST7), the third data acquisition step (ST8), the third offset value calculation step (ST9), the fourth data acquisition step (ST10), the mounting accuracy calculation step (ST5), and the judgment step (ST6) are repeatedly performed. That is, even if data is acquired at an inappropriate rotation angle of the inappropriate component mounting portion using the third offset value, if the predetermined mounting accuracy cannot be achieved with this third offset value, a new third offset value is acquired.

[0056] When the mounting accuracy of the mounting head 7 is judged to be appropriate (Yes in ST6), the update unit 30 updates the offset value (first offset value) stored in the head memory unit 7a to the second offset value or third offset value that is judged to be appropriate (ST11: offset value update process).

[0057] In this way, by executing the third data acquisition process (ST8), the third offset value calculation process (ST9), and the fourth data acquisition process (ST10) only for the conditions (combinations of component mounting sections 8(j) and rotation angles) that are determined to be inappropriate in the selection process (ST7), the time required to calculate the third offset value can be shortened, and the offset value can be calculated appropriately.

[0058] It is desirable that the number of times (e.g., 5 times) that the inappropriate component mounting unit places components D on board B at a rotation angle determined to be inappropriate in the third data acquisition process (ST8) is greater than the number of times (e.g., 3 times) that each of the multiple component mounting units 8(j) places components D on board B at a different rotation angle in the first data acquisition process (ST2). This makes it possible to remove the random component of the amount of misalignment in the mounting position and calculate an appropriate offset value.

[0059] As described above, component mounting apparatus M1 of the present embodiment is an offset value calculation system that includes: a data acquisition means 34 that uses a plurality of component mounting units 8(j), each having a nozzle 9 (component holder), to pick up components D from a tape feeder 10 (component supply unit) and mount them on a board B, and acquires data (amount of mounting position misalignment) related to the state of the components D mounted on the board B; a mounting accuracy calculation unit 26 that calculates the mounting accuracy of the plurality of component mounting units 8(j) based on the data acquired by the data acquisition means 34; a judgment unit 27 that judges whether the calculated mounting accuracy is appropriate; an offset value calculation unit 25 that calculates an offset value of the component mounting unit 8(j) based on the data acquired by the data acquisition means 34; and a selection unit (first selection unit 28 or second selection unit 29) that selects an inappropriate component mounting unit having an inappropriate offset value based on the data acquired by the data acquisition means 34.

[0060] In the offset value calculation system (component mounting device M1), when the judgment unit 27 judges that the mounting accuracy is not appropriate, the data acquisition means 34 reacquires the data of the improper component mounting part, and the offset value calculation unit 25 recalculates the offset value of the improper component mounting part based on the reacquired data. This makes it possible to properly calculate the offset value of the mounting head 7 (component mounting unit 8(j)).

[0061] The offset value calculation system is not limited to being composed of only component mounting device M1, and may be composed of component mounting system 1 in combination with management computer 3 and inspection device M2. For example, management computer 3 may include data extraction unit 24, offset value calculation unit 25, mounting accuracy calculation unit 26, judgment unit 27, first selection unit 28 or second selection unit 29 of data acquisition means 34, and the image of component D mounted on board B captured by head camera 14 of component mounting device M1 may be transmitted to management computer 3, and management computer 3 may calculate the offset value.

[0062] In addition, the inspection device M2 may be equipped with the data extraction unit 24, offset value calculation unit 25, mounting accuracy calculation unit 26, judgment unit 27, first selection unit 28 or second selection unit 29 of the data acquisition means 34, and the board B on which the component D has been mounted by the component mounting device M1 may be carried into the inspection device M2, and the component D mounted on the board B may be imaged by the inspection camera (imaging unit) of the inspection device M2, and the offset value may be calculated.

[0063] Also, only when the data acquisition means 34 of the component mounting device M1 acquires data for accuracy verification (second data, fourth data), the components D mounted on the board B may be conveyed to the inspection device M2 and the data (mounting position misalignment amount) may be acquired by the inspection device M2. Since the inspection camera of the inspection device M2 has higher detection accuracy than the head camera 14 of the component mounting device M1, it is possible to extract the mounting position misalignment amount with high accuracy and calculate a more appropriate offset value.

[0064] In the above embodiment, the mounting head 7 is provided with 16 component mounting units 8(1)-8(16), but the mounting head 7 is not limited to this. For example, the mounting head may be provided with 20, 12, 8, 4, 2, etc. component mounting units 8(j) other than 16. The present invention is also applicable to a rotary type mounting head provided with component mounting units 8. [Industrial Applicability]

[0065] The offset value calculation system, offset value calculation method, and component mounting apparatus of the present invention have the effect of being able to properly calculate the offset value of a mounting head, and are useful in the field of mounting components on a board. [Explanation of symbols]

[0066] 1. Component mounting system (offset value calculation system) 3. Management computer (offset value calculation system) 8, 8(j) Parts mounting section 9 Nozzle (part holder) 10 Tape feeder (parts supply section) 14 Head camera (imaging unit) 34 Data Acquisition Methods AN Nozzle shaft (shaft core) B Substrate D parts M1 Component placement device (offset value calculation system) M2 Inspection device (offset value calculation system) Xd Mounting position deviation in the X-axis direction (data) Yd: Displacement of mounting position in the Y-axis direction (data) θd θ direction mounting position deviation amount (data)

Claims

1. a data acquisition means for acquiring data relating to the states of the components mounted on the board by a plurality of component mounting units each having a component holder for holding the components, the components being picked up from the component supply unit and mounted on the board; a mounting accuracy calculation unit that calculates mounting accuracy of the component mounting units based on the data acquired by the data acquisition unit; A determination unit that determines whether the calculated mounting accuracy is appropriate; an offset value calculation unit that calculates offset values ​​of the component mounting units based on the data acquired by the data acquisition unit; a selection unit that selects an inappropriate component mounting unit, which is a component mounting unit having an inappropriate offset value, from among the plurality of component mounting units based on the data acquired by the data acquisition unit, When the determination unit determines that the fitting accuracy is not appropriate, The data acquisition means reacquires data on the improper part mounting portion, The offset value calculation system, wherein the offset value calculation unit recalculates the offset value of the improper component mounting portion based on the reacquired data.

2. the data acquiring means acquires first data of the plurality of component mounting units based on a first offset value; the offset value calculation unit calculates second offset values ​​for each of the component mounting units based on the first data; the data acquiring means acquires second data of the plurality of component mounting units based on the second offset value; The mounting accuracy calculation unit calculates the mounting accuracy based on the second data, When the determination unit determines that the fitting accuracy is not appropriate, The selection unit selects an inappropriate component mounting unit having an inappropriate second offset value based on the second data, The data acquisition means acquires third data of the improper component mounting portion based on the second offset value, 2. The offset value calculation system according to claim 1, wherein the offset value calculation unit calculates a third offset value of the improper component mounting portion based on at least the third data.

3. 3. The offset value calculation system according to claim 1, wherein the number of times that the improper component mounting unit mounts components on the board when the data acquisition means reacquires data is greater than the number of times that each of the plurality of component mounting units mounts components on the board when the data acquisition means acquires data from all of the plurality of component mounting units.

4. The component mounting units are capable of mounting components on a board by rotating the components around an axis, 4. The offset value calculation system according to claim 1, wherein the data acquisition means acquires the data by rotating the component holder through a plurality of different predetermined rotation angles using a plurality of the component mounting units, removing components from the component supply unit, and mounting the components on the board.

5. the selection unit determines whether the offset value is appropriate based on the data for each rotation angle, and selects the inappropriate component mounting unit; 5. The offset value calculation system according to claim 4, wherein the data acquisition means reacquires data on the rotation angle for which the offset value has been determined to be inappropriate by the inappropriate component mounting unit.

6. 6. The offset value calculation system according to claim 1, wherein the selection unit selects the improper component mounting unit based on a deviation of a mounting position of the component mounted on the board from a position where the component should be mounted.

7. 6. The offset value calculation system according to claim 1, wherein the selection unit selects the inappropriate component mounting unit based on a variation in the data.

8. 8. The offset value calculation system according to claim 1, wherein the selection unit selects the improper component mounting unit based on data acquired by the data acquisition means by having the component mounting unit mount a component based on the offset value.

9. 1. An offset value calculation method for calculating an offset value of a component mounting unit that has a component holder that holds components and that picks up components from a component supply unit and mounts them on a board, comprising the steps of: a first data acquisition step of mounting components on a board by a plurality of component mounting units based on a first offset value, and acquiring first data relating to states of the components mounted on the board; a second offset value calculation step of calculating second offset values ​​of the component mounting units based on the first data; a second data acquisition step of acquiring second data relating to states of the components mounted on the board by the component mounting units based on the second offset value; a mounting accuracy calculation step of calculating mounting accuracy of the component mounting portions based on the second data; a determination step of determining whether the calculated mounting accuracy is appropriate; a selection step of selecting an inappropriate component mounting unit, which is a component mounting unit having an inappropriate second offset value, based on the second data when the determination step determines that the mounting accuracy is inappropriate. a third data acquisition step of mounting a component on a board by the improper component mounting unit based on the second offset value, and acquiring third data relating to a state of the component mounted on the board; and a third offset value calculation step of calculating a third offset value of the improper component mounting portion based on at least the third data.

10. 10. The offset value calculation method according to claim 9, wherein the number of times that the improper component mounting unit mounts components onto the board in the third data acquisition step is greater than the number of times that each of the plurality of component mounting units mounts components onto the board in the first data acquisition step.

11. The component mounting units are capable of mounting components on a board by rotating the components around an axis, 11. The offset value calculation method according to claim 9 or 10, wherein in the first data acquisition step, the second data acquisition step, and the third data acquisition step, the component mounting unit rotates the component holder at a plurality of different predetermined rotation angles, and picks up components from the component supply unit and mounts them on a board, thereby acquiring the first data, the second data, and the third data.

12. In the selection step, the inappropriate component mounting portion is selected by determining whether the second offset value is appropriate based on the second data for each rotation angle, 12. The offset value calculation method according to claim 11, wherein in the third data acquisition step, third data of a rotation angle at which the second offset value is determined to be inappropriate by the inappropriate component mounting unit is acquired.

13. 13. The offset value calculation method according to claim 9, wherein in the selection step, the improper component mounting portion is selected based on a deviation of a mounting position of the component mounted on the board from a position where the component should be mounted.

14. 13. The offset value calculation method according to claim 9, wherein in the selecting step, the improper component mounting portion is selected based on a variation in the second data.

15. a fourth data acquisition step of mounting a component on a board by the improper component mounting unit based on the third offset value, and acquiring fourth data relating to a state of the component mounted on the board; 15. The offset value calculation method according to claim 9, wherein in the mounting accuracy calculation step, mounting accuracy of the plurality of component mounting portions is calculated based on the second data and the fourth data.

16. a parts supply unit that supplies parts; a plurality of component mounting units each having a component holder for holding a component, the component mounting units removing the components from the component supply unit and mounting the components on a board; a control unit that controls the component supply unit and the plurality of component mounting units to mount components on a board based on offset values ​​of the plurality of component mounting units; an imaging unit that images the component mounted on the board; a data extraction unit that extracts data related to a state of the component mounted on the board from an imaging result by the imaging unit; a mounting accuracy calculation unit that calculates mounting accuracy of the component mounting portions based on the data extracted by the data extraction unit; A determination unit that determines whether the calculated mounting accuracy is appropriate; an offset value calculation unit that calculates offset values ​​of the component mounting units based on the data extracted by the data extraction unit; a selection unit that selects an inappropriate component mounting unit, which is a component mounting unit having an inappropriate offset value, from among the plurality of component mounting units based on the data extracted by the data extraction unit, When the determination unit determines that the fitting accuracy is not appropriate, the control unit causes the improper component mounting unit to mount a component on a board; the data extraction unit re-extracts data on a state of the component mounted on the board by the improper component mounting unit from an imaging result by the imaging unit; The offset value calculation unit recalculates the offset value of the improper component mounting portion based on the re-extracted data.

17. the control unit causes the component mounting units to mount components on a board based on a first offset value; the data extraction unit extracts first data relating to a state of the component mounted on the board from an imaging result by the imaging unit; the offset value calculation unit calculates second offset values ​​for each of the component mounting units based on the first data; the control unit causes the component mounting units to mount components on a board based on the second offset value; the data extraction unit extracts second data relating to a state of the component mounted on the board from an imaging result by the imaging unit; The mounting accuracy calculation unit calculates the mounting accuracy based on the second data, When the determination unit determines that the fitting accuracy is not appropriate, The control unit determines whether the second offset value is appropriate based on the second offset value. The component is mounted on the board by the component mounting unit selected as the defective component. the data extraction unit extracts third data relating to a state of the component mounted on the board by the improper component mounting unit from an imaging result by the imaging unit; 17. The component mounting device according to claim 16, wherein the offset value calculation unit calculates a third offset value for the inappropriate component mounting portion based on at least the third data.

18. The component mounting units are capable of mounting components on a board by rotating the components around an axis, the control unit rotates the component holder through a plurality of different predetermined rotation angles using the plurality of component mounting units, and causes the component holder to pick up components from the component supply unit and mount them on the board; 18. The component mounting device according to claim 16, wherein the data extraction unit extracts data relating to a state of the component mounted on the board by the rotated component holder from an image captured by the imaging unit.

19. the selection unit determines whether the offset value is appropriate based on the data for each rotation angle, and selects the inappropriate component mounting unit; the control unit rotates the component to a rotation angle at which the offset value is determined to be inappropriate by the inappropriate component mounting unit, and mounts the component on the board; 20. The component mounting device according to claim 18, wherein the data extraction unit extracts data relating to a state of the component mounted on the board by the inappropriate component mounting unit from an imaging result by the imaging unit.

Images