JP3042190B2 - Device and method for detecting displacement of electronic component suction nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for detecting a displacement of an electronic component suction nozzle, and more particularly, to a head and a camera having an electronic component suction nozzle mounted integrally on a moving table, and to an electronic component. The present invention relates to a device and a method for detecting a displacement of an electronic component suction nozzle in an electronic component mounting device that mounts the electronic component at a predetermined coordinate position on a substrate.

[0002]

2. Description of the Related Art As an electronic component mounting apparatus for transferring and mounting electronic components on a substrate, for example, one disclosed in Japanese Patent Application Laid-Open No. 2-36599 is widely used.

In this type of electronic component mounting apparatus, a head that vacuum-adsorbs an electronic component to a nozzle and mounts the electronic component on a substrate, and a camera that detects positions of electrodes, position reference marks, and the like on the substrate are integrated on the same moving table. The relative distance between the optical axis of the camera and the center of the nozzle in the X and Y directions is registered in advance in the memory of the control computer as an offset distance. The offset distance can be obtained by assembling the head and the camera on the moving table and then measuring the optical axis and the position of the nozzle center by the measuring means.

[0004]

However, during the operation of the apparatus for a long time, the distance between the center of the nozzle and the optical axis of the camera fluctuates due to the thermal expansion and rattling of the parts. There has been a problem that the accuracy of mounting on the substrate gradually deteriorates.

Accordingly, an object of the present invention is to provide a device and a method for detecting a displacement of an electronic component suction nozzle which can easily and accurately determine the positional relationship between a nozzle and a camera.

[0006]

SUMMARY OF THE INVENTION For this purpose, the present invention relates to a pedestal provided below a moving path of a head and a camera.
The mover that can slide in the direction is mounted. The movable member is formed with a fitting hole into which the nozzle of the head is fitted.

[0007]

According to the above arrangement, the head is positioned above the movable element, the nozzle is inserted into the insertion hole of the movable element, and then the position of the insertion hole is detected by the camera. The relative distance in the direction can be determined.

[0008]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of an electronic component mounting apparatus.
Reference numeral 1 denotes a moving table, which is an X table 1 orthogonal to each other.
It consists of A and Y table 1B. The camera 3 and the head 4 are integrally attached to the tip of the Y table 1B. Reference numeral 7 denotes a ring-shaped light source integrally mounted on the camera 3 (see also FIG. 2). The head 4 is an electronic component 10
Is provided.

A clamper 12 for clamping and positioning the substrate 13 is provided in the middle of the substrate transport conveyor 11. A table 14 is provided on one side of the conveyor 11.
The table 14 is provided with a tray 15 in which the electronic components 10 are stored and an observation device 16 for detecting a displacement of the electronic components 10. The observation device 16 includes a stage 17 on which the electronic component 10 is mounted.
And a camera 18 for observing the electronic component 10 placed on the stage 17. The camera 3 is a substrate 1
The position of the substrate 13 is detected by observing the position reference marks A and B formed at the corners of the third, and the mounting position of the electronic component 10 is detected by observing the electrodes 19.

A second table 21 is provided on the other side of the conveyor 11. On this table 21,
A nozzle stocker 22 is provided. The nozzle stocker 22 contains a plurality of types of nozzles 5 and jig nozzles 6 having substantially the same shape as the nozzles 5. In order to replace the nozzle 5 according to the type of the electronic component 10, the head 4 arrives above the nozzle stocker 22, where the nozzle 5 moves up and down, so that the nozzle 5 is automatically replaced.

On the side of the table 21, a device 30 for detecting the positional deviation of the nozzle 5 is provided. FIG. 3 is a sectional view of the position shift detecting device 30, and FIG. 5 is a plan view. 3
Reference numeral 1 denotes a bottomed box-shaped pedestal installed on the table 21, in which a disk-shaped movable element 32 is slidably mounted in the XY directions. In the center of the upper surface of the movable element 32, an insertion hole 33 into which the lower end of the nozzle 5 is inserted is formed. As shown in FIG. 2, the lower end 5a of the nozzle 5 is generally tapered, so that the fitting hole 33 is pierced so that the lower end 5a matches.

A hole 34 is formed in the bottom of the pedestal 31.
Is connected. This tube 36 is connected to an air suction device 37 as fixing means for the mover 32,
On the way, an on / off switching valve 38 is provided. Normally, the movable element 32 is slidable on the bottom surface of the pedestal 31. However, when vacuum suction is performed through the tube 36, the movable element 32 is adsorbed and fixed on the bottom surface of the pedestal 31, and is released again when the vacuum suction state is released. Becomes

As described above, the nozzle 5 of the head 4 is replaceable, and a jig nozzle 6 can be mounted on the head 4 as shown in FIG. The outer shape of the jig nozzle 6 is substantially the same as the outer shape of the nozzle 5 and has a tapered lower end 6a. When the jig nozzle 6 is lowered,
The lower end 6a is fitted into the fitting hole 33.

This electronic component mounting apparatus is configured as described above, and the operation will be described next. In FIG. 1, prior to mounting the electronic component 10 on the substrate 13, the moving table 1 is driven to move the camera 3 above the substrate 13, and the position reference marks A and B are detected. Is detected in advance.

When the moving table 1 is driven, the head 4 moves above the tray 15, and the nozzles 5 move up and down so that the electronic components 10 in the tray 15 are picked up by vacuum suction. Next, the head 4 moves above the stage 17, where the X of the electronic component 10 is moved.
The camera 18 detects a displacement in the Yθ direction and the like. Next, the nozzle 5 picks up the electronic component 10 on the stage 17 again, and the head 4 moves above the substrate 13, where the nozzle 5 moves up and down, so that the electronic component 10 is mounted at a predetermined coordinate position. You. Here, among the positional deviations in the XYθ directions detected by the camera 18, the positional deviations in the X direction and the Y direction adjust the movement strokes of the head 4 in the X direction and the Y direction by driving the X table 1A and the Y table 1B. The positional deviation in the θ direction (rotation direction) is corrected by rotating the nozzle 5 by θ using a motor (not shown) built in the head 4.

In FIG. 2, the optical axis Z1 of the camera 3 is shown.
When the distance of the center Z2 of the nozzle 5 in the XY direction fluctuates, the mounting position of the electronic component 10 on the substrate 13 is deviated as described in the section of the related art. Therefore, the present apparatus checks whether or not the positional relationship between the optical axis Z1 of the camera 3 and the center Z2 of the nozzle 5 is changed as follows.

That is, the head 4 is connected to the nozzle stocker 22
And the jig nozzle 6 is mounted on the head 4 instead of the nozzle 5. Next, as shown in FIG. 3, the moving table 1 is driven to position the head 4 directly above the mover 32, whereupon the jig nozzle 6 is lowered to fit the lower end 6a into the fitting hole 33. Then, the mover 32 slides on the pedestal 31 so as to follow the lower end 6a of the jig nozzle 6 (see a chain line in FIG. 3). Then, the valve 38 is opened and the movable element 32 is vacuum-sucked from below, and the movable element 32 is
After being fixed on the upper side, the jig nozzle 6 is raised and the fitting hole 3 is
Escape from 3.

Next, the moving table 1 is driven and the camera 3
Is moved right above the mover 32, the light source 7 is turned on, and the mover 32 is observed from above (see FIG. 4). At this time, the moving distance of the moving table 1 is equal to the offset distance between the camera 3 and the nozzle 6. Then, the upper surface 32A of the mover 32
Since the light L1 applied to the camera is reflected right above and enters the camera 3, the upper surface 32A is observed brightly, but the light L2 incident on the slope of the fitting hole 33 is reflected obliquely upward to the camera 3. Since it does not enter, it is observed in black.

FIG. 5 is a plan view of the detecting device 30. A bright / dark image of the mover 32 is captured in the visual field Q of the camera 3, and FIG.
The insertion hole 33 is observed in black. Therefore, if the center position G of the insertion hole 33 is determined, the center position G is determined as the jig nozzle 6.
The jig nozzle 6 and the nozzle 5
Are the same, the center position G is exactly the center Z2 of the nozzle 5. The center position G can be easily obtained by image processing means such as a center of gravity detection method.

FIG. 6 shows the optical axis Z1 of the camera 3 and the nozzle 5
Shows the relative positional relationship of the center Z2 in the X and Y directions. In the figure, Z1 and Z2 are positions previously obtained by assembling the camera 3 and the head 4 on the moving table and then being measured by measuring means, and the offset distances in the X direction are X1 and Y. The offset distance in the direction is Y1. Z2A is the center position of the nozzle 5 detected by the camera 3 by the method shown in FIG. 3, and is shifted from the original position Z2 by ΔX in the X direction and ΔY in the Y direction.
Of course, the distances ΔX and ΔY are nothing but the sliding amounts of the mover 32 when the lower end 6 a of the jig nozzle 6 is fitted into the fitting hole 33. Such a relative displacement is caused by thermal expansion and play of each component as described above.

According to the above method, the positional relationship between the optical axis Z1 of the camera 3 and the center Z2 of the nozzle 5 can be easily detected.
Based on this result, the moving stroke of the head 4 in the X and Y directions by driving the moving table 1 is corrected.
The electronic component 10 can be correctly mounted on the substrate 13 at a predetermined coordinate position. Such an operation of confirming the positional relationship between the axis Z1 and the nozzle center Z2 may be performed at any time, and may be performed by interrupting the operation of mounting the electronic components 10 of the tray 15 on the substrate 13.

In order to accurately detect the center Z2 of the nozzle 5, the fitting hole 33 must be clearly recognized by the camera 3, as shown in FIG. To do this,
The upper surface 32A of the mover 32 and the insertion hole 33 need to be observed with a clear contrast.
It is desirable that the luminance of the upper surface 32A and the luminance of the fitting hole 33 are largely different from each other by applying a white paint or attaching a white seal to the 2A. In the above embodiment, the jig nozzle 6 to be fitted into the fitting hole 33 is specially prepared, but if the lower end 5a of the nozzle 5 is allowed to be damaged,
The lower end 5a of the nozzle 5 may be fitted into the fitting hole 33, and therefore the jig nozzle 6 is not always necessary.

[0024]

According to the present invention, a change in the positional relationship between the camera and the nozzle can be detected easily and accurately, and therefore, the accuracy of mounting the electronic component on the board can be maintained at a high level. It can be performed at any time, such as during mounting work.

[Brief description of the drawings]

FIG. 1 is a perspective view of an electronic component mounting apparatus according to an embodiment of the present invention.

FIG. 2 is a front view of a main part of the electronic component mounting apparatus according to the embodiment of the present invention during mounting of the electronic component.

FIG. 3 is a cross-sectional view of a main part of the jig nozzle according to one embodiment of the present invention being inserted into a mover.

FIG. 4 is a cross-sectional view of a main part of the camera according to one embodiment of the present invention when observing the mover

FIG. 5 is a plan view of a detection device according to an embodiment of the present invention.

FIG. 6 is a diagram illustrating a positional relationship between an optical axis and a nozzle center of a camera according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Moving table 3 Camera 4 Head 5 Nozzle 6 Nozzle (jig nozzle) 13 Substrate 30 Position shift detecting device 31 Pedestal 32 Movable element 33 Fitting hole

Claims (2)

(57) [Claims] An electronic component mounting apparatus comprising: a head for vacuum-adsorbing an electronic component to a nozzle to transfer and mount the electronic component on a substrate; a camera; and a moving table on which the head and the camera are integrated. A nozzle misalignment detection device, comprising: a pedestal disposed below a movement path of the head and the camera; and a mover slidably mounted on the pedestal in XY directions. Wherein a fitting hole for fitting the nozzle is formed in the electronic component suction nozzle. 2. A process of driving a moving table to position a head provided on the moving table above a mover slidably mounted on a pedestal in XY directions, and lowering nozzles of the head. A process of fitting the lever nozzle into a fitting hole formed in the mover, and after moving the nozzle out of the fitting hole, the moving table is driven again, and the camera provided in the moving table is used to perform the fitting. Determining the position of the nozzle in the X and Y directions with respect to the camera by detecting the position of the hole.