JP5227824B2 - Electronic component mounting equipment - Google Patents

Description

  The present invention relates to an electronic component mounting apparatus, and more particularly to an electronic component mounting apparatus capable of improving the tact by performing component recognition with high accuracy even during movement including acceleration / deceleration of a head unit.

  As illustrated in FIG. 1 (overall view) and FIG. 2 (main part configuration diagram), the substrate 8 is transported by the substrate transport unit 12 for transporting the substrate 8 in the X-axis direction and fixed to a predetermined mounting position. On the other hand, for example, an electronic component mounting apparatus (also referred to as a surface mounter or a mounter) that picks up and mounts electronic components from a component supply device 16 such as a tape feeder of the component supply unit 14 provided on both sides of the substrate transport unit 12. 10 is known. In the figure, 20 is a head unit for transferring components from the component supply device 16 to the substrate 8, 22 is an X-direction moving device for moving and positioning the head unit 20 in the X-axis direction, and 24 is A Y-direction moving device 26 for moving and positioning the head unit 20 together with the X-direction moving device 22 in the Y-axis direction includes, for example, a plurality of units arranged on the head unit 20 for sucking and picking up electronic components, for example. The head provided with the nozzle 28 at the tip (lower end), 30 is a substrate recognition camera mounted on the head unit 20 for photographing the mark of the substrate 8 from above, and 32 is adsorbed by the nozzle 28 This is a component recognition camera for photographing the electronic components and the like taken from below.

  Here, the suction (holding) position of the component sucked (held) by the nozzle 28 (hereinafter, the shift amount of the component position with respect to the nozzle center is referred to as a suction shift amount) is performed every time suction / mounting is performed. A little different every time. This is because the direction and position of the components in the component supply container arranged at the pickup position are slightly different from each other. As described above, since the amount of suction deviation is slightly different each time, in order to properly mount the component at the mounting position, the amount of movement of the head unit 20 from when the component is suctioned to when it is mounted depends on the amount of suction displacement. Need to be adjusted.

  In order to perform such adjustment of the movement amount, conventionally, for example, as shown in FIG. 3A (cross-sectional view seen from the side) and (B) (bottom view seen from the bottom), A laser recognition unit 40 is provided below the head unit 20 to detect the presence or absence and width of the component 6 based on the shadow generated in the belt, and the amount of suction deviation is recognized. The movement amount (or the stop position at the time of mounting) is corrected, and the suction unit 6 is mounted by moving the head unit 20 by the movement amount obtained as a result of this correction.

  In FIG. 3, 27 is a head shaft, 42 is a laser emitting part, and 44 is a laser receiving part.

  Here, the measurement of the amount of suction displacement is performed in the process of picking up the component 6 by the nozzle 28 and moving it to the mounting position. This is for improving work efficiency. More specific conventional automatic component mounting methods are described in Patent Documents 1 to 3, for example.

  However, since the head shaft 27 is not a perfect rigid body, during the acceleration / deceleration accompanying the movement, a flexure as exaggeratedly illustrated in FIG. 4 occurs. On the other hand, when the component 6 is mounted at the mounting position, since the head unit 20 is in a stopped state, the bending that occurred during acceleration / deceleration is also eliminated at this point. Therefore, as in the prior art, when the amount of movement of the head unit 20 is calculated based on the amount of suction deviation recognized during acceleration / deceleration of the head unit, and the component 6 is mounted by moving the head unit 20 based on this calculated value, There is a problem that the mounting position of the component 6 is shifted. Therefore, Patent Document 4 proposes correcting an error in the recognition position of a component caused by acceleration / deceleration applied to the head unit 20.

JP-A-6-55417 JP-A-6-252598 JP-A-10-290097 JP 2002-261494 A

  However, with the conventional acceleration correction method, it has been difficult to accurately capture the movement acceleration and deceleration of the head unit along the XY axes during component recognition due to axial position deviation, speed deviation, control delay, and the like.

  The present invention has been made to solve the above-described conventional problems, and makes it possible to accurately detect the holding position and holding angle of a component held by a nozzle regardless of acceleration / deceleration during movement of the head unit. Is an issue.

  The present invention relates to an electronic component mounting apparatus that holds a component at a pickup position by a nozzle provided in a head unit, moves the component to a mounting position as the head unit moves, and separates and mounts the component at the mounting position. , When detecting the holding position and holding angle of the component held by the nozzle while capturing the change in the shadow length of the component in the direction perpendicular to the head shaft while rotating the nozzle during the movement of the head unit. In addition, the problem is solved by detecting the holding angle while the head unit is moving, and detecting the holding position after the head unit is stopped.

  Here, when the component mounting operation for each board is the same for the same lot of boards, the positional deviation due to the head shaft moving during the head unit movement detected by the first board at the start of production is detected for the second and subsequent boards. By using the substrate and correcting the holding position detected while the head unit is moving, it is possible to omit the holding position detection after the head unit of the second and subsequent substrates is stopped.

  According to the present invention, time-consuming component recognition can be performed even during movement including acceleration / deceleration in the X and Y directions of the head unit, so that tact can be improved with high accuracy.

  In particular, when the parts mounting operation for each board is the same for the same lot of boards, the positional deviation due to the head shaft moving during the head unit movement detected by the first board at the start of production is corrected for the second and subsequent boards. By using the substrate and correcting the holding position detected while the head unit is moving, it is possible to omit the holding position detection after the head unit of the second and subsequent substrates is stopped.

Perspective view showing a general configuration of an electronic component mounting apparatus, with a part cut away The perspective view which shows the principal part structure of an electronic component mounting apparatus Similarly, the laser recognition unit on the head unit is (A) a sectional view seen from the side and (B) a bottom view seen from below. Side view showing misalignment due to bending during acceleration / deceleration The perspective view and block diagram which show the principal part structure of embodiment of this invention The figure which shows the example of the relationship between the rotation angle of the head shaft similarly detected by a laser recognition part, and the length of a shadow The top view which shows the displacement of the part due to acceleration / deceleration while moving Similarly, a flowchart showing the operation procedure of the adsorption operation control unit A plan view of a laser recognition unit for explaining another method of measuring the center position of a component when stopped

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 5 shows a main part of an embodiment of the electronic component mounting apparatus according to the present invention. Here, 50 is a main part of the main control apparatus that controls the entire apparatus, 52 is the operation of the entire apparatus, creation of a head recognition management table (hereinafter also simply referred to as a management table) 60, and the management table. The pick and place control unit that corrects and controls the position of the component using the data of 60, 54 is a management pointer indicating the current time point, 56 is an acceleration correction calculation unit that performs acceleration correction from the data of the management table 60, and 60 Is an operation history of XY (XY movement coordinates and stop are arranged in time order), a management pointer 56 at the current time point, a head for managing the recording of the deviation amount at that time, where the recognition started and ended. The recognition management table 70 is an X-axis driver for driving the X-direction moving device 22, 72 is a Y-axis driver for driving the Y-direction moving device 24, and 74 is for each axis. It provided the Z-axis driver 76, also provided on Jikugoto the θ axis driver 78, a laser recognition driver for laser recognition unit 40.

  In the above configuration, the component 6 sucked by the nozzle 28 of the head unit 20 is accelerated and decelerated by the X-direction moving device 22 and the Y-direction moving device 24 from the component supply device 16 to the substrate 8.

  Further, in order to mount the component 6 sucked from the component supply device 16 at high speed, the laser recognition unit 40 performs laser recognition during the XY operation by the X direction moving device 22 and the Y direction moving device 24. However, at that time, the component 6 on the head unit 20 during the acceleration / deceleration operation is subjected to a force on the head shaft 27 supporting the nozzle 28 by the acceleration / deceleration, and as shown in an exaggerated manner in FIG. The position of 6 is displaced.

  In the laser recognition unit 40, the component 6 is rotated by a θ-axis motor (not shown) for rotating the head shaft 27, the position and width of the shadow of the component 6 by the laser beam 43, and the rotation angle of the θ-axis motor. The center position of the part, the angle, the long side, and the short side size are obtained by the rotation angle of the head shaft 27 from the encoder indicating the above. When the part is displaced due to acceleration / deceleration of the part 6, the part illustrated in FIG. Although the relationship between the minimum width indicating the long side and the short side and the rotation angle of the head shaft 27 does not change, the center coordinates of the component 6 are deviated as illustrated in FIG. In addition, since the displacement of the component 6 is caused by acceleration / deceleration by the X-direction moving device 22 and the Y-direction moving device 24, the component 6 is displaced along the extension line of the XY motion locus (backward when accelerating and forward when decelerating). .

  Therefore, the laser beam 43 has an X-axis direction component in the acceleration / deceleration direction at the time of component measurement (in the case where the scanning direction of the laser beam 43 is the X-axis direction as shown in FIG. 3) regardless of the vertical and horizontal measurements of the component. It can be read with the amount of displacement of the component and the displacement of the component from the nozzle center added. Since the suction angle of the component does not change during acceleration / deceleration, the suction angle of the component acquired during acceleration / deceleration can be used as it is. Therefore, the headshaft 27 is bent by rotating the component after laser recognition so that it is in the 0 degree direction with no deviation of the suction angle, and reading the position of the component with a single (instantaneous) laser beam after stopping XY. Thus, it is possible to read the accurate amount of suction displacement in the X direction from the center of the nozzle 28 of the component 6 in a non-distorted state. Further, the component 6 is rotated 90 degrees, and the deviation in the Y-axis direction from the nozzle center is measured by the laser beam 43.

  In this way, after the XY movement and laser recognition by the X-direction moving device 22 and the Y-direction moving device 24 are performed on the picked-up component, the current displacement amount of each component is read, so From the XY deviation, it can be seen how much the XY coordinate deviation has occurred due to acceleration / deceleration.

  Furthermore, in the case of substrates of the same lot, they are mounted on the first substrate at the start of production, and this management table 60 has an XY operation history for one substrate, so that it can be mounted on the second and subsequent substrates. Usually, since the operation is exactly the same, the management table 60 for the second and subsequent substrates can be omitted.

  A specific processing procedure of the suction mounting control unit 52 is shown in FIG.

  First, in step S1, it is determined whether or not production is started. If the production has started, the process proceeds to step S2, and all the contents of the management table 60 are cleared. Next, in step S3, it is determined whether or not it is the first board. If it is the first board, the process proceeds to step S4, and the management pointer 54 is set to the head of the management table 60.

  Next, in the case of the simultaneous suction illustrated in FIG. 8, the following operations are started simultaneously for all the heads. That is, for example, in step S5 shown for the head 1, the XY coordinates of the head 1 at this time are compared with the head 1 of the corresponding stage of the management table 60. Next, in step S6, it is determined whether or not the coordinates are the same. When the coordinates are not the same, that is, when it is determined that the coordinates are the first (first substrate), the process proceeds to step S7, and it is set that the corresponding stage is changed. In step S8, the corresponding XY coordinates in the management table 60 are updated. After step S8 is completed, or when the determination result in step S6 is positive and the same coordinates as before, the process proceeds to step S9, the part is sucked, and the part is recognized in step S10.

  Next, after synchronizing with the completion of the suction of all the instruction heads, it is determined in step S11 whether or not it is a mounting position. When the determination result is positive and it is determined that the coordinates are mounted, the process proceeds to step S12 to determine whether or not the coordinates are the same. If the determination result is NO and it is determined that the coordinates are the first (first substrate), the process proceeds to step S13, and it is set that the corresponding stage is changed. In step S14, the corresponding XY coordinates in the management table 60 are updated. After step S14 is completed, or when the determination result in step S12 is positive and the same coordinates as before are determined, the process proceeds to step S15 to determine whether or not there is a change. If the determination result is positive, the process proceeds to step S16, where the component is rotated to 0 degrees with no deviation of the suction angle by the angle recognized during the XY movement, and the component position size is measured once. Next, in step S17, the component position size is measured once by rotating 90 degrees. Next, the process proceeds to step S18, and the difference between the recognition results at the time of stop and movement (head shaft distortion) represented by the following equation is recorded in the management table 60.

Here, the distortion of the head shaft 27 due to acceleration / deceleration is expressed by the following equation as shown in FIG.
Head shaft distortion due to acceleration / deceleration (ΔXhm, ΔYhm)
= H Deviations during movement of nozzle parts (ΔX ′, ΔY ′)
-H Displacement when nozzle parts are stopped (ΔX, ΔY) (1)

  After step S18 or when the determination result of step S15 is NO and it is determined that the result is the same as before, the process proceeds to step S19, where the recognition result at the time of movement is corrected by the difference of the recognition result of the management table 60, and the mounting position To correct. Next, the process proceeds to step S20, and components are mounted.

  Next, after synchronizing with the completion of mounting of all the heads, the process proceeds to step S21. When all the heads have mounted one component, the management pointer 54 is incremented by 1 and the process proceeds to the next stage of the management table 60.

  Although FIG. 8 shows an example of simultaneous adsorption, the present invention can be applied even if it is not simultaneous adsorption.

  For example, in the case of a leaded component instead of a chip component, if it can be assumed that the axis deviation when moving the head is the same for the X axis and the Y axis, the mounting correction can be made only by measurement at the position rotated by the adsorption deviation angle θ. You can also ask for data.

  Next, another example of a method for measuring the component center position at the time of stopping will be described.

  In the algorithm for obtaining the mounting correction data, the suction deviation angle θ of the component 6 is obtained by the laser recognition unit 40 during the XY movement.

Next, A (x ₂ , y ₂ ) and C (x ₃ , y ₃ ) shown in FIG. 9 are obtained at the position where the head shaft stops after the component measurement.

Next, the suction deviation angle θ is rotated, and a (x ₁ , y ₁ ) and d (x ₄ , y ₁ ) are obtained at a position where the component is parallel to the laser beam 43 and stopped.

Next, based on the above data, the head shaft center Wc (xc, yc) is obtained using the following equation.
xc = (x ₁ + x ₄ ) / 2 (2)
yc = (y ₁ + y ₄ ) / 2 (3)
Here, y ₁ = (x ₂ −x ₁ cos θ) / sin θ (4)
y ₄ = (x ₃ −x ₄ cos θ) / sin θ (5)

  The obtained Wc is the center position of the component when the component and the laser beam are stopped in parallel. Therefore, by calculating the Wc (xc, yc) and the laser offset data, highly accurate mounting correction data for component mounting that is not affected by the XY movement is obtained without rotating the head shaft by 90 ° after the movement is stopped. be able to.

  Further, in each suction mounting operation, suction of all the heads is completed, laser recognition is started in all the heads simultaneously with the start of the XY operation, and laser recognition of all the heads is completed by the first mounting point of all the heads. When it is clear that laser recognition is performed at a specific timing, such as, the start coordinates (last adsorption coordinates) acquired in advance are simply the end coordinates (stop coordinates for the first mounting). It is also possible to use correction amounts classified according to distance, direction, route, speed, acceleration / deceleration, etc.

  Here, when measuring the displacement in advance, the tip of the nozzle mounted on the head in a pseudo manner is regarded as a component, and laser recognition of the component position during XY acceleration / deceleration (component position including the displacement due to acceleration / deceleration) is performed. It is also possible to perform laser recognition of the parts position at the time of stopping (parts position without deviation due to acceleration / deceleration).

  Further, in the case of measurement with a laser that irradiates in the Y direction as described above, the position of the component is shifted due to the X-direction component of acceleration / deceleration at the time of laser recognition. In the range where the X-direction component of the movement amount is small and the range of deviation is extremely small relative to the mounting accuracy of the electronic component mounting apparatus, it can be ignored. Note that the laser irradiation direction is not limited to the Y direction. The number of heads is not limited to a plurality, and may be a single head.

DESCRIPTION OF SYMBOLS 6 ... Component 8 ... Board | substrate 10 ... Electronic component mounting apparatus 16 ... Component supply apparatus 20 ... Head unit 22 ... X direction moving apparatus 24 ... Y direction moving apparatus 26 ... Head 27 ... Head shaft 28 ... Nozzle 40 ... Laser recognition part 42 ... Laser light emitting unit 43... Laser light 44. Laser receiving unit 50.

Claims (2)

In the electronic component mounting apparatus that holds the component at the pickup position by the nozzle provided in the head unit, moves the component to the mounting position along with the movement of the head unit, and separates and mounts the component at the mounting position.
When detecting the holding position and holding angle of the component held by the nozzle while capturing the change in the shadow length of the component that occurs in the direction perpendicular to the head shaft while rotating the nozzle during the movement of the head unit,
An electronic component mounting apparatus, wherein a holding angle is detected while the head unit is moving, and a holding position is detected after the head unit is stopped.   When the component mounting operation for each board is the same for the same lot of boards, the positional deviation caused by the head shaft moving while moving the head unit detected by the first board at the start of production is used for the second and subsequent boards. 2. The electronic component mounting apparatus according to claim 1, wherein the holding position detection after the head unit is stopped for the second and subsequent boards is omitted by correcting the holding position detected while the head unit is moving. .

Images