JP2005222976A - Surface mounting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve productivity by further increasing a travel speed of a movable bed by adopting a configuration for clearly imaging a component for packaging and a reference mark by a camera. <P>SOLUTION: The focus of the camera 11 for imaging the component 7 for packaging sucked by a suction nozzle 9 and a reference mark 10 for image processing is positioned at a position lower than the component 7 for packaging, in which height of the component 7b becomes the highest when the component 7 is being packaged on a printed-wiring board 3. The suction nozzle 9 is positioned at the same height as the focus when imaging the component 7 for packaging, and is positioned at the upper portion of the component 7b for packaging in which the height becomes the highest on the printed-wiring board 3 when traveling on the printed-wiring board 3. A moving device 41 for the reference mark is provided for moving the reference mark 10 inside a head unit. The moving device 41 pumps the reference mark 10 between a position that is flush with the focus of the camera 11, and a position that is higher than the component 7b for packaging in which the height becomes the highest while being packaging on the printed-wiring board. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface mounter including an image pickup apparatus that picks up an image of a mounting component sucked by a suction nozzle with a camera.

  Conventionally, as a surface mounter that picks up a mounting component by a suction nozzle and mounts it on a printed wiring board, for example, as described in Patent Document 1, whether or not the mounting component sucked by the suction nozzle is correct In order to determine whether or not the actual position and angle of the mounting component are detected, there is a configuration in which the mounting component sucked by the suction nozzle is imaged by a camera.

  The surface mounting machine disclosed in Patent Document 1 is provided with a mark (hereinafter referred to as a reference mark) that can determine the position of the suction nozzle on the lower surface of the moving head that supports the suction nozzle. This reference mark is imaged by the camera together with the mounting component sucked by the suction nozzle. The conventional surface mounter obtains the positional deviation amount and angle of the mounting component with respect to the suction nozzle of the mounting component from the position of the reference mark in the image captured by the camera by image processing, and the moving direction and moving amount of the moving head during mounting In such a configuration, the mounting component is mounted at a correct position on the printed wiring board by correcting the above.

The depth of field is set so that the camera can clearly pick up both the mounting component sucked by the lower end of the suction nozzle and the reference mark at a position spaced above the mounting component. Has been. In addition, this camera is configured so that the mounting component and the reference mark can be imaged while the moving head is moving in the horizontal direction. The reason for imaging while moving the moving head is to shorten the imaging time and the surface mounting tact time.
In addition, the applicant could not find any prior art documents closely related to the present invention by the time of filing other than the prior art documents specified by the prior art document information described in the present specification. .
JP-A-5-63398

  The conventional surface mounting machine described above is required to further reduce the surface mounting tact time in order to improve productivity. In order to meet this demand, it is most effective to increase the moving speed of the moving head. However, when the moving speed of the moving head is increased, the exposure time when taking an image with the camera is shortened, so that it becomes difficult to obtain a clear image. Such a problem can be solved to some extent by opening the aperture of the camera and increasing the amount of light received by the camera. However, when this configuration is adopted, since the depth of field of the camera becomes shallow, it is impossible to focus on both the mounting component and the reference mark.

  In this way, in order to focus the mounting component and the reference mark with the camera aperture open, the mounting component and the reference mark may be positioned so as to be substantially equal in height. That is, by focusing the camera on the reference mark and picking up an image in a state where the suction nozzle is raised so that the mounting component is located at the same height as the reference mark, it is possible to focus on both.

  However, since the height of the reference mark (the height of the lower end portion of the moving head) is higher than the mounting surface of the printed wiring board, as described above, when the image of the mounting component is raised to the same height as the reference mark, the image is taken. Since the imaging position and the mounting position are different in the vertical direction, if the suction nozzle is lifted or lowered slightly, the mounting component may be mounted with a deviation from the correct position of the printed wiring board. . The reason why the height of the reference mark is higher than the mounting surface of the printed wiring board is because the moving head moves horizontally on the printed wiring board in order to position the mounting component at the mounting position. This is to prevent the reference mark (the lower end portion of the moving head) from coming into contact with other components already mounted on the printed wiring board during movement. That is, the moving head is provided at a position spaced upward from the mounting component having the maximum mounting height.

  In addition, since the mounting component is raised to the height of the reference mark and an image is taken, there is a problem that the tact time becomes longer by the time required for the raising operation and the lowering operation after imaging. In particular, when a mounting component is mounted on a printed wiring board having a relatively low height, the time loss further increases because the mounting component is unnecessarily raised to a high position.

  The present invention has been made to solve such problems, and is produced by further increasing the moving speed of the moving head while adopting a configuration in which the mounting component and the reference mark can be clearly imaged by the camera. An object is to realize a surface mounter capable of improving the performance.

  To achieve this object, a surface mounting machine according to the present invention is provided with a moving unit configured to be movable in a horizontal direction, a suction nozzle provided to be movable up and down on the moving unit, and the moving unit. An image processing reference mark is provided, the mounting component taken out from the component supply unit by the suction nozzle and the reference mark are moved in the horizontal direction, and imaged from below by the camera in the middle of the moving path, and the mounting is performed. In the surface mounting machine for transferring the parts for mounting to a predetermined position on the printed wiring board, the focal point of the camera is set to a position lower than the mounting part where the height when mounted on the printed wiring board is highest. The suction nozzle is positioned at the same height as the focal point when the mounting component is imaged, and the height is the highest on the printed wiring board when moving on the printed wiring board. The mounting part is configured to be positioned above the mounting part to be raised, and the moving unit has the position where the reference mark is at the same height as the focal point of the camera, and the mounting part having the highest height on the printed wiring board. A reference mark moving device that reciprocates between higher positions is provided.

In the surface mounter according to the present invention, the reference mark is brought into contact with the mounting component by moving the reference mark to a position higher than the mounting component having the highest height when mounted on the printed wiring board. The moving head can be moved above the printed wiring board so that it does not occur.
Further, by moving the reference mark to a position that is the same height as the focal point of the camera, the camera can be accurately focused on the reference mark. Furthermore, the focus of the camera can be accurately adjusted to the mounting component by causing the mounting component to be attracted to the suction nozzle and moved above the camera while being positioned at the same height as the focal point of the camera. For this reason, even when the aperture is opened so that the amount of light received by the camera increases, the mounting component and the reference mark can be captured by the camera so that the image is clear.
Therefore, the moving speed of the moving head can be increased, and a surface mounter with high productivity can be provided.

(First embodiment)
Hereinafter, an embodiment of a surface mounter according to the present invention will be described in detail with reference to FIGS.
FIG. 1 is a plan view of a surface mounter according to the present invention, FIG. 2 is a front view of an upper portion of the surface mounter, FIG. 3 is a configuration diagram of the main part, and FIG. FIG. 2B shows a state when moving on the printed wiring board. FIG. 4 is a block diagram for explaining the height of each member, FIG. 5 is a block diagram of a control system of the surface mounter, and FIG. 6 is a flowchart for explaining the operation during imaging.

  In these drawings, what is denoted by reference numeral 1 is a surface mounter according to this embodiment. The surface mounter 1 includes a conveyor 4 for transporting the printed wiring board 3 to the upper part of the base 2 and a moving device 6 for moving a head unit 5 described later. The head unit 5 constitutes a moving head in the present invention.

  The conveyor 4 is configured to convey the printed wiring board 3 in the left-right direction of the base 2 in FIG. 1 (hereinafter, this direction is simply referred to as the X direction) and hold it at a working position by a clamping mechanism (not shown). ing. On both sides of the conveyor 4, a tape feeder 8 in which mounting parts 7 (see FIGS. 3 and 4) are housed, and mounting parts sucked by suction nozzles 9 (see FIGS. 2 and 3) described later. 7 and a reference mark 10 (see FIG. 3), which will be described later, are provided.

As shown in FIGS. 3 and 4, the camera 11 includes an illuminating unit 13 having an LED 12 as a light source and a sensor body 15 having a CCD solid-state imaging device 14, and one tape on the base 2. It is attached between the feeder 8 and the conveyor 4 at a position lower than the conveying surface of the printed wiring board 3 so as to face upward.
The sensor body 15 of the camera 11 is a CCD linear sensor in which CCD solid-state imaging devices 14 are arranged in parallel in the vertical direction in FIG. 1 (hereinafter, this direction is simply referred to as Y direction), and is formed in the illumination unit 13. The mounting component 7 and the reference mark 10 are imaged one-dimensionally through the Y-direction slit 13a (see FIG. 1).

  Further, the camera 11 is formed so that the amount of received light is maximized, and therefore, the camera 11 is configured to be focused on one place above. The focal position of the camera 11 according to this embodiment is positioned at substantially the same height as the height A of the mounting surface of the printed wiring board 3 as shown in FIG.

  The moving device 6 is movable between a Y-direction moving device 22 having two fixed rails 21, 21 extending in the Y direction above the conveyor 4 and the fixed rails 21, 21. And an X-direction moving device 24 having a rail 23. The head unit 5 is attached to the X-direction moving device 24. The head unit 5 and the moving device 6 are controlled in moving direction, distance, speed, and the like by a control device 25 (see FIG. 5) described later.

The Y-direction moving device 22 moves the movable rail 23 of the X-direction moving device 24 in the Y direction by a ball screw shaft 26 extending along the fixed rail 21 and a Y-axis servo motor 27 that drives the ball screw shaft 26. Make a round trip. The movable rail 23 is fixed to a nut member 26 a of the ball screw shaft 26. The Y-axis servomotor 27 is provided with position detecting means 28 comprising an encoder.
The X-direction moving device 24 reciprocates the head unit 5 in the X direction by a ball screw shaft 29 arranged in parallel with a movable rail 23 extending in the X direction and an X-axis servo motor 30 that drives the ball screw shaft 29. . The X-axis servo motor 30 is provided with position detecting means 31 comprising an encoder.

  As shown in FIG. 2, the head unit 5 is provided with eight suction heads 32 that hold the suction nozzle 9 at intervals in the X direction. An imaging reference mark 10 to be described later is provided. Further, as shown in FIG. 5, the head unit 5 includes a Z-axis servo motor 33 that moves the suction head 32 in the vertical direction (Z direction), and an R that rotates the suction head 32 with the vertical direction as the axial direction. A shaft servomotor 34 is provided for each suction head. The Z-axis servo motor 33 and the R-axis servo motor 34 are respectively provided with position detecting means 35 and 36 comprising encoders. The head unit 5 according to this embodiment is configured to be able to perform an elevating operation and a rotating operation for each of the eight suction heads 32.

  The suction head 32 is configured so that the fixed suction nozzle 9 can be replaced with one having a different size or a different intake suction port diameter. As is well known in the art, the suction nozzle 9 sucks the mounting component 7 at the lower end where the air suction port opens. The suction nozzle 9 descends when the mounting component 7 on the tape feeder 8 is sucked. After the mounting component 7 is sucked, the suction nozzle 9 is raised until the lower surface of the mounting component 7 is slightly higher than the upper surface of the tape that houses the mounting component 7 from which the cover tape has been peeled off. Can move horizontally without interfering with the tape. When moving above the printed wiring board 3 while the mounting component 7 is sucked, the height of the lower end of the sucked mounting component 7 is indicated by a two-dot chain line B in FIG. It is positioned so as to be higher than the height of the component 7a. When the mounting component 7 is mounted on the printed wiring board 3, the suction nozzle 9 is lowered. In the present embodiment, the upper surface of the tape attached to the tape feeder 8 in a state where the cover tape is peeled off is substantially the same as the height A of the mounting surface of the printed wiring board 3.

As shown in FIGS. 2 to 4, the reference mark 10 is formed on the lower end surface of a columnar member 10 a extending in the vertical direction. The columnar member 10a is mounted on a portion of the head unit 5 that supports the suction head 32 (a portion that does not move in the vertical direction) via the reference mark moving device 41. The reference mark moving device 41 according to this embodiment includes:
The guide member 42 for restricting the horizontal movement of the columnar member 10a is provided, and the columnar member 10a is moved up and down between a predetermined lowered position and an elevated position by an air cylinder (not shown). Yes. The operation of the air cylinder is controlled by a control device 25 described later.

As shown in FIG. 3A, the lowered position is such that the position of the reference mark 10 is the same height as the focal point of the camera 11 (in this embodiment, substantially the same as the height A of the mounting surface of the printed wiring board 3). Height). As shown in FIGS. 3B and 4, the raised position is higher than the mounting component 7 b having the highest height when the reference mark 10 is mounted on the printed wiring board 3. Is set to The height of the upper end of the highest mounting component 7b is indicated by a two-dot chain line C in FIG.
By moving the columnar member 10 a to the lowered position by the reference mark moving device 41, the reference mark 10 is positioned at the focal position of the camera 11. A clear image can be obtained. This image is sent from the camera 11 to the control device 25 described later as image data.

As shown in FIG. 5, the control device 25 includes a main control means 43, a servo motor driver 44, an image processing means 45, a calculation means 46, and the like, and the mounting component 7 is attached to the tape feeder 8. In other words, a configuration is adopted in which the mounting operation to be transferred to the printed wiring board 3 is comprehensively executed.
The main control means 43 stores a program for controlling the operation of all the actuators (each servo motor, solenoid, air cylinder, etc.) of the surface mounter 1 according to this embodiment. Control signals are sent to the driver 44 and the driver 47 of the head unit 5.
The image processing means 45 is configured to perform predetermined image processing on the image data sent from the camera 11. The computing means 46 determines whether or not the mounting component 7 is sucked to the suction nozzle 9 and whether or not the mounting component 7 sucked to the suction nozzle 9 is correct, and this mounting component. 7 is used to obtain the position, angle, and the like.

Next, the mounting operation of the surface mounter 1 according to this embodiment will be described with reference to the flowchart shown in FIG.
First, in step S1 of FIG. 6, the control device 25 performs eight mounting components to be mounted this time from a data library (board information) that stores mounting data for the printed wiring board 3 being transported on the base 2. Data (component information) such as 7 types and positions are read for each suction head 32. The control apparatus according to this embodiment is configured to handle eight mounting components 7 as one suction group, and is configured to read component information for each suction group from the board information.

  Next, in step S2, the control device 25 moves the head unit 5 above the component supply unit of the tape feeder 8, causes the suction nozzle 9 of each suction head 32 to suck the predetermined mounting component 7, and after the suction, At that position, the lower surface of the mounting component 7 is raised to a height slightly higher than the upper surface of the tape housing the mounting component 7 from which the cover tape has been peeled off (approximately the mounting surface height A). As a result, the mounting component 7 can be moved horizontally without interfering with the tape, and the lower surface of the mounting component 7 has substantially the same height (height A) as the focal position of the camera 11. At the same time, the control device 25 operates the reference mark moving device 41 to position the reference mark 10 at the lowered position (the same height as the focal position of the camera 11). In the surface mounter 1 according to this embodiment, the position at which the mounting component 7 is sucked by the tape feeder 8 is separated from the camera 11 in the Y direction. 5 is moved beside the camera 11 (position adjacent to the X direction).

  Thereafter, as shown in step S3, the control device 25 moves the head unit 5 in the X direction so that the mounting component 7 and the reference mark 10 sucked by the suction nozzle 9 pass above the camera 11. Move horizontally along. At this time, the control device 25 performs imaging by the camera 11 in synchronization with the movement of the head unit 5. In this embodiment, since the reference mark 10 is positioned at the same height as the focal position of the camera 11 by the reference mark moving device 41, the head unit 5 is simply moved in the X direction as described above. However, both the reference mark 10 and the mounting component 7 can be imaged by the camera 11 in a focused state.

  At this time, the image captured by the camera 11 clearly shows the reference mark 10 and the mounting component 7 for each suction head 32, and the control device 25 indicates whether the mounting component 7 is present, correct or incorrect by the image. At the same time, the suction position and angle of the actual mounting component 7 are detected, and target mounting position data and the like are corrected for each suction head 32. Since the height of the mounting component 7 that picks up the image is substantially the same as the mounting surface of the printed wiring board 3, even if the suction nozzle 9 moves up and down diagonally, it has high accuracy. A target mounting position can be set.

In this imaging process, the control device 25 raises each suction head 32 to a predetermined height in the order in which imaging of the mounting component 7 is completed, as shown in Steps S4 to S7. The predetermined height is a position where the lower end of the mounting component 7 is higher than the height of the mounted mounting component 7a (indicated by a two-dot chain line B in FIG. 4) (hereinafter, this position is referred to as an XY moving height). That means. At this time, the reference mark moving device 41 is operated to raise the reference mark 10 that has been imaged to the raised position.
After all the mounting components 7 and the reference marks 10 are imaged in this imaging process, the control device 25 obtains a moving speed when moving the head unit 5 above the printed wiring board 3 in step S8.

  This moving speed is a speed at which the mounting unit and the reference mark 10 imaged at the end are faster than the XY moving height and the head unit 5 does not move onto the printed wiring board 3. Set to. The reason why the moving speed is set in this way is to prevent the mounting component 7 or the reference mark 10 imaged at the end from coming into contact with the mounted mounting component 7 a on the printed wiring board 3. After obtaining the moving speed, the control device 25 moves the head unit 5 in the X direction and the Y direction at the moving speed toward the target position on the printed wiring board 3 in step S9. Then, as shown in steps S <b> 10 to S <b> 11, after the mounting parts 7 and the reference marks 10 of all the suction nozzles 9 have been raised to the XY movement height, the control device 25 adjusts the head unit 5 as necessary. Increase movement speed.

  After the head unit 5 has moved to the target position, the control device 25 mounts all the mounting components 7 sucked by the eight suction heads 32 on the printed wiring board 3 in step S12. Thereafter, in step S13, the control device 25 determines whether all the mounting components 7 are mounted on the printed wiring board 3 positioned on the base, and all the mounting components 7 are mounted. Performs the end operation. If the mounting of the mounting component 7 on the printed wiring board 3 has not been completed, the control device 25 proceeds to step S14, and the height of the upper ends of the eight mounting components 7 mounted this time is the already mounted. It is determined whether or not the height is higher than the height B of the mounting component 7a.

  At this time, if the currently mounted mounting component 7 includes a component that is higher than the height B of the mounted mounting component 7a, the control device 25 updates the data of the XY moving height in step S15. Then, the process proceeds to step S16. If it is determined that the mounting component 7 mounted this time is lower than the height B of the mounted mounting component 7a, the process directly proceeds to step S16. In step 16, the control device 25 initializes the component information read in step S <b> 1 and moves the head unit 5 to the tape feeder 8 side in order to suck the mounting component 7 of the next suction group.

In the surface mounter 1 configured as described above, when the head unit 5 is moved on the printed wiring board 3, the reference mark 10 is mounted on the mounting component 7 (mounted mounting component 7 a or mounting height that maximizes the mounting height). The mounting component 7 and the reference mark 10 can be positioned at the focal position of the camera 11 at the time of imaging.
For this reason, the surface mounter 1 captures the mounting component 7 and the reference mark 10 with the camera 11 whose depth of field becomes shallow in order to increase the amount of received light. Can be obtained. As a result, the surface mounter 1 according to this embodiment was able to increase the moving speed of the head unit 5 as compared with the conventional one.

In the embodiment described above, the focal position of the camera 11 is set to be substantially the same as the height A of the mounting surface of the printed wiring board 3, and the mounting surface A is mounted on the tape feeder 8. In the above example, the upper surface of the tape for housing the component 7 is positioned at substantially the same height. However, when the suction nozzle 9 has a small inclination when moving up and down, the height A of the mounting surface and the mounting surface during imaging are used. There may be a difference between the lower surface position of the component 7, that is, the focal position of the camera 11, and the focal position of the camera 11 has the highest height when mounted on the printed wiring board 3. The position can be appropriately changed as long as the position is lower than 7b, and the height of the upper surface of the tape that accommodates the mounting component 7 mounted on the tape feeder 8 can also be appropriately changed. The focal position of the camera 11 and the position of the upper surface of the tape can be positioned below the height A of the mounting surface of the printed wiring board 3 or can be positioned above the height A. When the focal position of the camera 11 is higher than the mounting component 7b having the highest height when mounted on the printed wiring board 3, it is substantially the same as the lower surface position of the mounting component 7 at the time of imaging. It is not necessary to raise or lower the reference mark 10 which is set to the height.
Further, the camera 11 is not limited to one using a CCD linear sensor, and can be formed using another solid-state imaging device. In this case, the reference mark 10 and the mounting component 7 can be temporarily stopped above the camera at the time of imaging according to the type of the solid-state imaging device to be used.

  Although an air cylinder is used as the power source of the reference mark moving device 41 according to this embodiment, a solenoid, a servo motor, or the like can be used as the power source instead of the air cylinder.

It is a top view of the surface mounting machine concerning the present invention. It is a front view of the upper part of a surface mounter. It is a block diagram of the principal part. It is a block diagram for demonstrating the height of each member. It is a block diagram of a control system of a surface mounter. It is a flowchart for demonstrating the operation | movement at the time of imaging.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Surface mounting machine, 3 ... Printed wiring board, 5 ... Head unit, 7, 7a, 7b ... Mounting components, 9 ... Adsorption nozzle, 10 ... Reference mark, 10a ... Columnar member, 11 ... Camera, 32 ... Adsorption head 41. Reference mark moving device.

Claims (1)

A moving unit configured to be movable in a horizontal direction, a suction nozzle provided to be movable up and down on the moving unit, and an image processing reference mark provided on the moving unit, and a component supply unit provided by the suction nozzle The mounting component and the reference mark taken out from the surface are moved in the horizontal direction and imaged from below by a camera in the middle of the movement path, and the mounting component is transferred to a predetermined position on the printed wiring board. In the mounting machine, the focus of the camera is positioned at a position lower than the mounting component where the height when mounted on the printed wiring board is the highest, and the suction nozzle is positioned when the mounting component captures the focus. When moving on the printed wiring board, it must be positioned above the mounting component with the highest height on the printed wiring board. Move the reference mark to reciprocate between the position where the reference mark is at the same height as the focal point of the camera and a position higher than the mounting component having the highest height on the printed wiring board. A surface mounting machine characterized by providing a device.

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