JP2002234131A - Screen printing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a screen printing machine by improving a mechanism for recognizing the image of a substrate and an image recognition position. SOLUTION: A positioning unit 50 is arranged on the lower side of a fixed screen 25, and the substrate 61 is moved vertically by the positioning unit 50. While the positioning unit 50 on which the substrate 61 is mounted is brought down, a camera unit 14 having an image recognition camera 15 is introduced between the screen 25 and the substrate 61 to recognize the image of the substrate 61.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen printing apparatus, and more particularly to a screen printing apparatus in which a work is superposed on a lower surface of a screen and a paste-like substance is printed on the surface of the work.

[0002]

2. Description of the Related Art When an electronic component is mounted on a circuit board, it is necessary to solder electrodes of the electronic component and connection lands of the circuit board. Therefore, conventionally, cream solder has been used, and the cream solder is printed on a circuit board before mounting components. After that, the components are mounted, guided to a reflow furnace, and the solder of the cream is melted to solder the electrodes of the electronic components.

Here, a screen printing apparatus for printing cream solder on a circuit board prints cream solder on a land of the circuit board through a pattern formed of holes provided on a screen. Therefore, such a screen printing apparatus detects a squeegee unit that pushes cream solder into a pattern on the screen, a cleaning unit that cleans cream solder remaining on the back side of the screen and the pattern, and an alignment mark provided on a circuit board. A camera unit for recognizing the position of the circuit board, a positioning table for holding the circuit board and positioning in the X-axis direction, the Y-axis direction, the Z-axis direction, and the θ-axis direction.

A conventional method for image recognition of a circuit board will be described with reference to FIGS. A squeegee 2 slides on a screen 1 of a screen printing apparatus. On the other hand, a substrate 3 is attached to the lower surface of the screen 1 by a substrate mounting jig 4 so as to be overlapped. I have. The image of the substrate 3 held by the substrate mounting jig 4 is recognized by the image recognition camera 5 at a position off the lower side of the screen 1.

[0005]

In order to print cream solder on the circuit board 3 with high accuracy, the position of the board 3
In particular, the alignment mark provided on the substrate 3 is detected by the image recognition camera 5, and the position of the circuit substrate 3 is corrected based on the data and printed. Two alignment marks are provided on the substrate 3, and these alignment marks are provided as far away as possible. The image recognition camera 5 enlarges the screen in order to recognize the alignment mark with necessary accuracy. Here, the lens of the camera 5 expands at a magnification of several times to several tens times.

For this reason, it is impossible to simultaneously recognize two alignment marks on the substrate 3 on one screen. Therefore, in order to take the image of the alignment mark into the camera 5, the substrate 3 is fixed by the jig 4 and then the camera 5
Is moved in the X-Y axis directions. Alternatively, a method is used in which the substrate 3 is moved in the X-axis direction and the Y-axis direction by the jig 4 while the camera 5 is fixed. In any of the methods, image recognition is conventionally performed as shown in FIG.

However, according to such a configuration, there is a problem that a space for performing image recognition of the substrate 3 by the camera 5 is required in addition to a space for printing cream solder, so that the screen printing apparatus cannot be downsized.
The squeegee unit, the cleaning unit, and the camera unit that constitute the cream solder printing apparatus are each mounted on a moving table in the X-axis direction. These three
Conventionally, the set table has been arranged in a plane at a position off the horizontal plane from the screen 1. Therefore, according to such a configuration, there is a problem that the size of each unit is increased and rigidity is reduced, and it is difficult to reduce the size of the device.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and has a problem that the printing space and the space for image recognition by the camera are performed in the same space in the horizontal direction. And to provide a more compact screen printing device.

[0009]

The main invention of the present application is a screen printing apparatus which prints a paste-like substance on the surface of a work by overlapping a work on the lower surface of the screen. Means for vertically separating each other, an image recognition camera for recognizing an image of the surface of the work, and a horizontal moving means for moving the image recognition camera between the screen and the work, The present invention relates to a screen printing apparatus characterized in that the image recognition camera is moved between the screen and the work in a state where the screen and the work are vertically separated from each other to perform image recognition on the surface of the work. .

Here, the image recognition camera may recognize the alignment mark of the work. Further, the image recognition camera may recognize an image on a lower surface of the screen. The image processing apparatus further includes position adjustment means for adjusting a horizontal relative position between the screen and the work, by adjusting a horizontal relative position between the screen and the work based on image recognition of the image recognition camera. , High precision screen printing is achieved.

Another invention of the present application relates to a screen printing apparatus in which a paste-like substance is printed on the surface of a work by superimposing the work on the lower surface of a screen. A screen printing device provided on the top and extending substantially horizontally, and an image recognition camera supported movably in the horizontal direction by the guide means and recognizing the surface of the work. It is about.

Still another aspect of the present invention relates to a screen printing apparatus in which a paste-like substance is printed on the surface of a work by overlapping the work on the lower surface of a screen. Guide means provided on the base and extending in a substantially horizontal direction;
The present invention relates to a screen printing apparatus which is supported by the guide means so as to be movable in a horizontal direction and includes a cleaning unit for cleaning a lower surface of the screen.

Still another aspect of the present invention is directed to a screen printing apparatus which prints a paste-like substance on the surface of a work by superimposing the work on the lower surface of a screen. Guide means provided on the base and extending in a substantially horizontal direction;
A squeegee that is supported movably in the horizontal direction by the guide means and moves while pressing the paste-like substance on the screen to print the paste-like substance on the work. It is.

Here, the guide means may be arranged so as to extend in parallel with the work transfer direction. Further, the guide means may be a pair of guide rails arranged vertically on the support base substantially in parallel with each other. Further, the image recognition camera, the cleaning unit, or the squeegee is cantilevered by the guide means, and an end portion in a width direction of the screen and a portion opposite to the support base is a free end. Good.

Still another aspect of the present invention relates to a screen printing apparatus in which a paste-like substance is printed on the surface of a work by superimposing the work on the lower surface of a screen. Guide means provided on the base and extending in a substantially horizontal direction;
An image recognition camera that recognizes an image of the surface of the work, and a cleaning unit that cleans a lower surface of the screen, wherein both the image recognition camera and the cleaning unit are guided by the guide unit. And a screen printing apparatus.

Here, the paste-like substance may be cream solder, and the work may be a circuit board.
According to such a configuration, the screen printing apparatus prints cream solder on the circuit board.

In a preferred aspect of the invention included in the present application, the X-axis direction of the substrate fixed by the positioning table,
An image recognition camera for recognizing two alignment marks provided on the substrate in order to correct the misalignment in the axial direction and the θ-axis direction for printing; The present invention relates to a cream solder printing apparatus in which a movable range in the Y-axis direction is arranged almost directly below a screen.

In another preferred embodiment, a carriage unit includes a camera unit having an image recognition camera for recognizing a substrate, a cleaning unit for cleaning the back surface of the screen, and a squeegee unit for printing cream solder by sliding on the screen. The carriage is moved along a guide rail in the X-axis direction, which is a direction parallel to the direction of loading and unloading the substrate into and from the printing apparatus, and such a guide rail is moved in front of the apparatus. The present invention relates to a cream solder printing apparatus which is arranged horizontally on a vertical support base provided on the opposite back side with a predetermined interval vertically.

In still another preferred embodiment, in such a cream solder printing apparatus, a camera unit having an image recognition camera for recognizing a substrate, and guide means for moving a cleaning unit for cleaning the back surface of the screen. And a guide rail extending in the X-axis direction.

According to the above-described embodiment, in particular, according to the printing apparatus in which the movable range of the camera unit is arranged almost directly below the screen, the camera moves between the screen and the substrate in the X-axis direction and the Y-axis direction. While performing image recognition, the printing apparatus is downsized. In addition, according to the configuration in which the guide rails for the slides of the camera unit, the cleaning unit, and the squeegee unit are arranged on the upright support base so as to extend vertically above and below the support base, the size of the printing apparatus can be reduced. In addition, by using the guide rails of the camera unit and the cleaning unit together, the number of guide means is reduced, and the apparatus can be made more compact.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show a front view and a side view of the screen printing apparatus, and FIGS. 3 and 4 show a front view and a side view of such a screen printing apparatus in principle. The outline of the screen printing apparatus will be described with reference to these drawings.

This screen printing apparatus has a support base 10 which stands upright on the back side. The support base 10 has guide rails 11 and 12 extending vertically in the lateral direction on a lower front surface thereof and vertically spaced apart from each other by a predetermined distance. The carriages 13 are movable by the guide rails 11 and 12. I support it. The carriage 13 supports a camera unit 14, and the image recognition camera 15 is supported by the camera unit 14. The image recognition camera 15 is for performing image recognition of a substrate described later.

Another carriage 18 is supported by the pair of guide rails 11 and 12. The carriage 18 supports a cleaning unit 19. The cleaning unit 19 is for cleaning a lower surface of a screen described later with a cleaning tape 20 as shown in FIG. Then, the cleaning tape 20 is fed from the feed roller 21 of the cleaning unit 19, and the cleaning tape 20 that has been cleaned is taken up by the take-up roller 22.

A screen 25 is provided above the moving range of the camera unit 14 and the cleaning unit 19. The screen 25 is stretched with its four sides fixed by a frame 26. Then, the frame 26 is fixed at a predetermined position of the printing apparatus by the mounting frame 27.

On the screen 25, a pair of squeegees 3
1, 32 are provided. The squeegees 31 and 32 are supported by supports 33 and 34, respectively.
34 are supported by air cylinders 35 and 36, respectively.

A pair of guide rails 37 extending laterally is provided on the upper surface of the support base 10.
38, and these guide rails 37, 38
The carriage 39 is supported so as to be movable.
The squeegees 31 and 32 are moved laterally by such a carriage 39.

Next, a description will be given of a positioning device for positioning a substrate constituting a work below the screen 25. FIG. 5 shows a specific configuration of the positioning device, and FIG. 6 shows a principle diagram thereof. As shown in FIGS. 5 and 6, this device includes a base 43, and four Z-axis guides 44 are provided upright on the base 43. Then, the lower Z
The axis table 45 is supported so as to be movable in the Z-axis direction, that is, in the vertical direction. The Z-axis table 45 is a rod 47 of an air cylinder 46 attached to the lower side of the base 43.
The Z-axis guide 4
4 allows it to be moved up and down freely. The upper moving position is regulated by a stopper 48 provided on the Z-axis guide 44.

On the Z-axis table 45, a Y-axis table 51 is provided.
, And an X-axis table 52 is mounted on the Y-axis table 51. The θ-axis table 53 is mounted on the X-axis table 52. A mounting plate 54 is mounted on the θ-axis table 53.

On the mounting plate 54, four Z-axis guides 55 are provided so as to extend upward, and these guides 55 support a Z-axis table 56 so as to be able to move up and down. The motor (not shown) provided on the side and the ball screw 58 of the Z-axis table 56 are linked by a timing belt (not shown) so that the Z-axis table 56 can be moved up and down. Has become. A substrate mounting jig 60 is mounted on the Z-axis table 56, and the substrate mounting jig 60 sucks and holds the substrate 61. As a result, the positioning unit 50 for the substrate 61 is disposed below the screen 25.

Next, a mechanism for holding the substrate 61 provided on the mounting plate 54 will be described. Supports 65 and 66 are provided on the mounting plate 54 on both sides thereof, respectively. A fixed guide 67 is fixed to the upper end of the left support 65 as shown in FIG. On the other hand, a moving guide 69 is attached to the upper end of the right support 66 via a base 68. A conveyor belt 70 is supported by these guides 67 and 69.

Each of the supports 65 and 66 has an arm 7 extending laterally as shown in FIGS.
3 and 74, and holding claws 77 and 78 are provided on the arms 73 and 74 via support members 75 and 76. As described later, these pressing claws 77 and 78 are configured to press both sides in the width direction of the substrate 61 introduced onto the positioning device from above.

The fixed guide 67 and the moving guide 69
As shown in FIG. 5, a carry-in conveyor 81 and a discharge conveyor 82 are arranged on the upstream side and the downstream side of the conveyor belt 70 respectively supported by the conveyor belt 70. It is introduced onto a substrate mounting jig 60 of 50, and is discharged by a discharge conveyor 82 after printing is completed.

As shown in FIG. 7, a cylinder 85 is attached to the lower part of the camera unit 14 having the image recognition camera 15 downward. This cylinder 8
The rod 5 constitutes a correction pin 86, and the correction pin 86 presses a substantially central portion of the upper surface of the substrate 61 placed on the substrate mounting jig 60 as shown in FIGS. By doing so, the warpage of the substrate 61 is corrected.

As described above, the screen printing apparatus of the present embodiment includes the screen 25 and is fixed by the mounting frame 27 via the frame 26. Then, a substrate 61 is disposed directly below the screen 25,
It is fixed by a substrate mounting jig 60 mounted on a positioning unit 50 movable in the axial direction, the Z-axis direction, and the θ-axis direction (see FIGS. 1 and 3).

As shown in FIGS. 1 to 4, a camera unit 14 is mounted on the carriage 13, and an image recognition camera 15 is mounted on the camera unit 14. Although not shown here, the carriage 13 is configured to be driven via a servomotor and a ball screw. The carriage 13 is supported by a pair of upper and lower guide rails 11 and 12 extending laterally on the support base 10, and such a configuration saves space and improves rigidity.

Further, the carriage 18 on which the cleaning unit 19 is mounted is guided by the guide rails 11 and 12. That is, here, the guide rail of the carriage 18 of the cleaning unit 19 is shared with the guide rails 11 and 12 of the camera unit 14.

The squeegees 31, 32 are placed on the screen 25.
A squeegee unit consisting of That is, it has a pair of squeegees 31, 32, each of which can be moved up and down separately by the air cylinders 35, 36. The squeegees 31 and 32 are mounted on a carriage 39, and the carriage 39 is moved by a motor (not shown) and a ball screw. A guide mechanism for moving the carriage 39 is two upper and lower guide rails 37 provided on the support base 10 and extending in the horizontal direction.
4 has the same configuration as the guide mechanism.

As shown in FIGS. 5 and 6, the positioning unit 50, which is disposed below the screen 25 and positions the substrate 61, is configured such that the substrate 61 is carried thereon by a carry-in conveyor 81. I have. 5 and 6 show a state in which the substrate 61 is carried in and placed on the substrate mounting jig 60. FIG. The substrate 61 carried in by the carry-in conveyor 81 is transferred by the conveyor belt 70 and stopped on the substrate mounting jig 60 by a stopper (not shown).

The board mounting jig 60 is mounted on the upper Z-axis table 56, and is guided by four Z-axis guides 55 so as to be movable in the Z-axis direction. A ball screw 58, a timing belt (not shown), and a motor (not shown) are provided for moving the Z-axis table 56, thereby constituting a lifting mechanism of the upper Z-axis table 56. I have.

Mounting plate 5 for supporting the Z-axis guide 55
4 is mounted on a θ-axis table 53, and the table 53 moves in the rotation direction. Although a driving device for the θ-axis table 53 is not shown here, it may be constituted by, for example, swinging with a cylinder or a motor provided with a rotating shaft or a rotating table with a driving device. An X-axis table 52 is disposed below the table, and is moved by a drive mechanism using a motor and a ball screw so as to be movable in the X-axis direction. A Y-axis table 51 is arranged below the Y-axis table 51, and a driving mechanism using a motor and a ball screw is provided so as to be movable in the Y-axis direction.

Below the Y-axis table 51, a Z-axis table 4 is provided.
5 are guided in the Z-axis direction by four guide shafts 44. On the table 45, the Y-axis table 51, the X-axis table 52, the θ-axis table 53, and the Z-axis table 56 are all arranged. It can be moved in the Z-axis direction. The lower Z-axis table 45 is driven by a cylinder 46 to move up and down.

With the above configuration, the positioning unit 50 can be moved in the X-axis, Y-axis, Z-axis, and θ-axis directions as a whole, and the Z-axis direction is composed of two axes. Thus, a five-axis positioning unit 50 is configured as a whole.

Particularly, in the screen printing apparatus according to the present embodiment, the uppermost Z-axis table 56 is driven by a motor (not shown) and a ball screw 58, and the lower Z-axis table 45 is driven by a cylinder 46. , The positioning unit 50 which is compact and has high rigidity can be obtained.

The substrate 61 introduced onto the substrate mounting jig 60 of the positioning unit 50 is a screen 25
And guides 67 and 69 restrict the position from both sides in the width direction. These guides 67 and 69 are provided on the conveyor belt 7.
0, and the conveyor belt 70 is positioned below both ends of the substrate 61 to be introduced.
Pressing claws 77 and 78 are arranged outside the guides 67 and 69 and on both sides thereof. These pressing claws 77 and 78 are for pressing both ends in the width direction of the substrate 61 from above.

Positioning unit 5 on which substrate 61 is mounted
When 0 is raised, the substrate 61 is pressed against the lower surface of the screen 25 as shown in FIG. Here, the right guide 69 is configured to be movable in the width direction of the substrate 61, and presses and fixes the substrate 61 against the fixed guide 67 on the opposite side. The guides 67 and 69 on both sides are mounted on a mounting plate 54 on the θ-axis table 53. Here, the conveyor belt 70 is attached to the guides 67 and 69.
Is provided. The guides of these conveyor belts 70 are composed of a plurality of rollers, and are conveyor belts driven by motors. Such a conveyor belt 70 has guides 67 and 69 on both sides.
It is attached to the lower surface of.

The substrate mounting jig 60 for mounting and holding the substrate 61 thereon has a large number of holes for vacuum suction on its surface. The board mounting jig 60 is mounted on the upper Z-axis table 56.

When the squeegees 31 and 32 shown in FIG. 10 move while the substrate 61 is pressed against the lower surface of the screen 25, a printing operation is performed. That is, when the squeegees 31 and 32 slide on the screen 25, the cream solder is stirred and printing is performed. Here a pair of squeegees 3
1 and 32 are provided, and two squeegees 31 and 3 are reciprocated.
By alternately using two, printing on two substrates 61 is performed.

Prior to such printing, the warpage of the substrate 61 is corrected by the mechanism shown in FIG. In FIG. 7, the screen 25 is fixed to the main body via a frame 26. The conveyor 8 is located below the screen 25.
The substrate 61 is introduced by 1 and 70. An air cylinder 85 having a warp correcting pin 86 for correcting such a warp of the substrate 61 is attached to the camera unit 14 together with the image recognition camera 15, and is supported by the carriage 13 so as to be rotatable in the X-axis direction. I have.

Pressing pawls 77 and 78 for pressing the substrate 61 shown in FIG. 7 from above on both sides thereof are located on both sides of the conveyor belt 70, and are rotatably supported via hinges 91 and 92. The fixed sides of the holding claws 77 and 78 are supported by sliding plates 95 and 96 that can move in the Y-axis direction, respectively. The pressing claws 77 and 78 are pressed in a closing direction, that is, downward by a tension spring, and are opened and closed by air cylinders 93 and 94.

The lower slide plate 95 of the left holding claw 77 is attached to the mounting plate 54 of the positioning unit 50 via the support 66.
It is supported by. On the other hand, the lower slide plate 96 of the right claw 78 is supported by a support 66, and the support 66 is supported on a slide plate 98 that can move in the Y-axis direction.

Next, the operation of the screen printing apparatus having such a configuration will be described. First, an outline of the overall operation of the printing apparatus will be described. When the substrate 61 does not exist on the conveyor belt 70 shown in FIG.
The Y-axis table 51 and the X-axis table 52 operate, and the upper portion of the positioning unit 50 is
Move to one side. Then, the carry-in conveyor 81 and the conveyor belt 70 are operated to transfer the substrate 61 to the conveyor belt 7.
The conveyor 70 is stopped at a predetermined position. FIG. 5 shows a state where the substrate 61 has stopped at this position.

Next, the upper Z-axis table 56 is raised by a motor and a ball screw 58 (not shown), and the substrate 61 is lifted from the conveyor 70. After that, the fixing of the substrate 61 and the correction of the warpage are performed. These operations will be described later. After correcting the warp of the substrate 61 and fixing the substrate 61 to the substrate mounting jig 60 of the positioning unit 50, the camera unit 14 is moved along the guide rails 11 and 12 by the carriage 13 and the image recognition camera 1 is moved.
5 moves above the substrate 61 to recognize the alignment mark on the substrate 61.

In conjunction with the detection of the alignment mark on the substrate 61 by the image recognition camera 15, the control unit causes the X-axis table 52, the Y-axis table 51, .theta.
The axis table 53 is driven to correct the displacement of the substrate 61. After that, the air cylinder 46 is operated to raise the entire positioning unit 50 and move it upward to a position where the substrate 61 contacts the lower surface of the screen 25.

In such a state, the squeegees 31, 3
2 slides on the screen 25 to print the cream solder. After a series of printing operations is completed, the ball screw 5
8 to move the upper Z-axis table 56 downward,
As a result, the substrate 61 is separated from the screen 25 by the plate. Thereafter, the lower Z-axis table 45 is lowered by the air cylinder 46. Next, the substrate mounting jig 60
Is released from the substrate 61 by suction. Thereafter, the X-axis table 52 and the Y-axis table 51 are driven, the positioning unit 50 is moved to the discharge conveyor 82 side, the conveyor belt 70 and the discharge conveyor 82 are moved together, and the substrate 61 is moved by the discharge conveyor 82. Discharge.

In performing the printing operation as described above, the substrate 61 is fixed on the positioning unit 50, and the warpage of the substrate 61 is corrected to perform clamping. This operation will be described with reference to FIG. In FIG. 12A, the substrate 61 is introduced by the conveyor 70 to a position almost directly below the screen 25. That is, the substrate 61 is placed on both sides of the belt 7.
0 moves it down the screen. At this time, guides 67 and 68 are located on both sides of the substrate 61, respectively. The conveyor belt 70 is supported by these guides 67 and 68. These guides 6
Pressing claws 77 and 78 are located outside the reference numerals 7 and 68, respectively.

FIG. 12A shows a state in which the substrate 61 has been carried into the printing apparatus, and thereafter, various operations before printing are sequentially performed. In FIG. 12B, the right guide 68 advances to the left, and clamps the substrate 61 on the belt 70 from the left and right directions so as to press against the guide 67 on the opposite side of the substrate 61. At this time, the presser pawl 78 also advances in the same direction.

Next, as shown in FIG. 12C, the pressing claws 77 and 78 on both sides are respectively raised and thereafter moved in the width direction of the substrate 61 so as to be close to each other. Move and presser claw 7 at that position
7, 78 stop. Next, as shown in FIG. 12D, the holding claw 7 in which the board mounting jig 60 is raised and waits on the upper side.
The upper and lower ends of the substrate 61 are pressed against the substrates 7 and 78. After this, the upper Z-axis table 56 moves up. Immediately after this operation, the substrate mounting jig 60 vacuum-adsorbs and fixes the substrate 61.

Next, as shown in FIG.
7 and 78 once retreat upward, move to the side, and then descend to release the restraint of the substrate 61 by these pressing claws 77 and 78. In this state, the camera unit 14 is introduced between the substrate 61 and the screen 25, and the substrate 6
1 is recognized by the image recognition camera 15. In addition, the camera unit 14 is provided with an air cylinder 85 having a correction pin 86 as shown in FIG. 7, and the air cylinder 85 is operated to move a predetermined position of the substrate 61 downward by the correction pin 86. Pressing, thereby correcting the warpage of the substrate 61 and improving the adhesion to the substrate mounting jig 60.

In general, there are many cases where the substrate 61 introduced into the printing apparatus is warped. If cream solder is printed on the substrate 61 as it is in a warped state, it is difficult to perform accurate printing. In addition, the pattern holes of the screen 25 and the lands of the substrate 61 cannot be accurately aligned during plate alignment. If there is a warp, the substrate 61 moves in the X-axis direction or the Y-axis direction with respect to the screen 25 when the plate is separated,
The cream solder printed on the lands of the substrate 61 is likely to be displaced, removed, or cracked, and is likely to cause problems.

However, such a disadvantage is solved by correcting the warpage of the substrate 61 as described above. Thereafter, the positioning unit 50 moves the X-axis direction, the Y-axis direction, and θ.
The position of the substrate 61 is corrected by moving in the axial direction. Thereafter, as shown in FIG. 12F, the lowermost Z-axis table 45 is moved upward by the cylinder 46 so that the substrate 61 is brought into close contact with the lower surface of the screen 25 to perform printing.

Next, the operation of recognizing the image of the substrate 61 prior to printing will be described. In FIG. 14, the screen 25 is stretched on the
Are fixedly arranged via the. A squeegee 31 is arranged so as to move on this. Here, the substrate 61 on which the image recognition is performed is introduced to the lower side of the screen 25 while being fixed to the substrate mounting jig 60 of the positioning unit 50. That is, the substrate 61 carried into the printing apparatus is fixed to the substrate mounting jig 60 and the screen 25
Is located at a position almost directly below.

Here, in order to perform high-precision printing, it is necessary that the image recognition camera 15 recognizes images of two alignment marks on the substrate 61. The alignment marks are provided at distant positions such as diagonally opposite ends of the surface of the substrate.
Is moved in the X-axis direction and the Y-axis direction to recognize the alignment mark.

Here, the data taken from the camera 15 is processed, and the position correction amounts of the substrate 61 with respect to the screen 25 in the X-axis direction, the Y-axis direction, and the θ-axis direction are calculated. The data of the position correction amount is taken into the control device and subjected to arithmetic processing, whereby the X-axis table 52, the Y-axis table 51, and the θ-axis table 53 of the positioning unit 50 are operated to correct the substrate 61. Thus, the substrate 61 is moved to an accurate position with respect to the screen 25.

In particular, the feature of the screen printing apparatus according to the present embodiment is that, as shown in FIG. 1 to FIG. 4 and FIG. The image recognition camera 15 is moved in the X-axis direction and the Y-axis direction by the carriage 13 to recognize the alignment mark on the substrate 61.

As a result, as compared with the case where the camera 15 or the substrate 61 is moved at a position horizontally distant from the screen 25 to recognize the alignment mark on the substrate 61, the space in the horizontal plane is greatly reduced.
This makes it possible to realize a significant reduction in the size of the screen printing device. Further, since the moving amount is small, downsizing of the positioning unit 50 is also achieved at the same time.

As described above, according to the screen printing apparatus of this embodiment, the image recognition is performed in a state where the substrate 61 carried into the apparatus is fixed on the substrate mounting jig 60 of the positioning unit 50 after a predetermined operation. The camera 15 moves in the X-axis direction and the Y-axis direction to recognize a preset alignment mark on the substrate 61. After that, the camera unit 14 having the image recognition camera 15 is moved to the position shown in FIGS.
Then, it returns to the right position, that is, the origin position, and stops.

As described above, screen 2 is obtained by image recognition.
The displacement between the pattern provided on the substrate 5 and the land provided on the substrate 61 is calculated in three directions of the X-axis direction, the Y-axis direction, and the θ-axis direction. Then, the positioning unit 50 moves in the X-axis direction, the Y-axis direction, and the θ-axis direction by the calculated shift amount, thereby correcting the position shift. Thereafter, the positioning unit 50 further moves up and stops at a position where the substrate 61 contacts the lower surface of the screen 25. Thereafter, the squeegees 31 and 32 slide on the screen 25 to print the cream solder on the substrate 61.

As described above, the upper surface of the substrate 61 is
When the squeegees 31 and 32 slide on the screen 25 while being pressed against the lower surface of 5, the printing of the cream solder on the substrate 61 is performed. Thereafter, as shown in FIG. 10, the squeegee 31 stops at a position off the substrate 61 to the right. Squeegee 31 is screen 25
An appropriate printing force is applied to the screen 25 when sliding on the upper side. Therefore, in a state where the squeegee 31 is deviated to the right from the substrate 61 and stopped,
The force applied to the screen 25 is received by the guides 67 and 69 on both sides shown in FIG.

At this time, as shown in FIG. 10, the screen 25 is in a state of being bent downward by a small amount. The amount of deflection in the height direction of the screen 25 at this time is, for example, about 0.1 m.
m. The setting of the amount of bending can be arbitrarily adjusted by the gap between the upper surface of the substrate 61 and the upper surfaces of the guides 67 and 69 when the substrate 61 is raised in the Z-axis direction, that is, in the vertical direction by the positioning unit 50. It is.

As shown in FIG. 10, the squeegee 31
1 and stopped on the screen 25, the upper Z-axis table 56 is lowered by a motor and a ball screw 58 (not shown), whereby the substrate 61 is moved downward together with the substrate mounting jig 60. The separation of the screen from the screen 25 is performed.

The screen 25 is moved by this separating operation.
Is pulled down. The main reason is that the cream solder entering the holes of the screen 25 is printed on the lands on the surface of the substrate 61, and the cream solder moves the screen 25 downwards due to the viscosity generated on the sides of the holes of the pattern of the screen 25 described above. By pulling. The force for pulling the screen 25 downward generated during such separation of the plate is applied to the guide 6.
Since it can be received on the upper surfaces of 7 and 69, the amount of downward bending of the screen 25 can be extremely small. After such separation, the squeegees 31, 3
2 is raised by the air cylinders 35 and 36.

By such a separation operation, the substrate 6
It is possible to minimize and minimize the movement and vibration of the screen 25 when the plate is released after the cream solder is printed on the land of one. From this, the substrate 6
1 enables high-precision screen printing of cream solder on the top.

Although the invention of the present application has been described with reference to one embodiment shown in the drawings, the invention of the present application is not limited to the above embodiment, and various modifications may be made within the technical idea of the invention included in the present application. Is possible. For example, the above embodiments relate to a cream solder printing apparatus, but the invention of the present application is widely applicable to various other paste-like substance printing apparatuses.

[0074]

The main invention of the present application is a screen printing apparatus in which a paste-like substance is printed on the surface of a work by overlapping the work on the lower surface of the screen, and the screen and the work are vertically separated from each other. Means, an image recognition camera for recognizing the surface of the work, and a horizontal moving means for moving the image recognition camera between the screen and the work, wherein the screen and the work are vertically separated from each other. An image recognition camera is moved between a screen and a workpiece to recognize an image on the surface of the workpiece.

Therefore, according to such a screen printing apparatus, the position at which the image of the work is recognized by the image recognition camera and the position at which the surface of the work is printed by the screen can be set to the same position in the horizontal direction. Therefore, a small screen printing apparatus which requires a small space in the horizontal direction is provided.

Another main invention of the present application is a screen printing apparatus in which a paste-like substance is printed on the surface of a work by superimposing the work on the lower surface of a screen. Guide means provided on a base and extending in a substantially horizontal direction, and an image recognition camera supported by the guide means so as to be movable in the horizontal direction and recognizing an image of a surface of the work. It is.

Therefore, according to such a screen printing apparatus, it is possible to move the image recognition camera for recognizing the surface of the work in the horizontal direction by the horizontally extending guide means provided on the support base. In particular, almost no space is required for the moving mechanism of the image recognition camera, which makes it possible to save space in the horizontal plane direction, thereby achieving a reduction in the size of the screen printing apparatus.

[Brief description of the drawings]

FIG. 1 is a front view illustrating the overall configuration of a screen printing apparatus.

FIG. 2 is a side view of the screen printing apparatus.

FIG. 3 is a front view showing a principle configuration of the screen printing apparatus.

FIG. 4 is a side view of the same.

FIG. 5 is a front view showing the structure of a substrate positioning unit.

FIG. 6 is a front view showing the configuration of the same principle.

FIG. 7 is a side view showing a configuration for correcting the warpage of the substrate.

FIG. 8 is a front view showing the operation of correcting the warpage of the substrate.

FIG. 9 is a side view of the same.

FIG. 10 is a front view of a main part in a state where printing is completed.

FIG. 11 is a side view of the main part.

FIG. 12 is a side view showing the operation of loading and positioning a substrate below the screen.

FIG. 13 is a plan view of a substrate.

FIG. 14 is a front view illustrating image recognition of a substrate.

FIG. 15 is a front view illustrating image recognition of a conventional substrate.

FIG. 16 is a plan view showing image recognition of the substrate.

[Explanation of symbols]

1 ‥‥ screen, 2 ‥‥ squeegee, 3 ‥ board, 4 ‥
{Board mounting jig, 5} Image recognition camera, 10} Support base, 11, 12} Guide rail, 13} Carriage, 14} Camera unit, 15} Image recognition camera, 18} Carriage, 19 cleaning unit, 20 cleaning tape, 21 feeding roller, 22 winding roller, 25 screen, 26
{Frame, 27} Mounting frame, 31, 32} Squeegee, 33, 34 {Support, 35, 36} Air cylinder, 37, 38 {Guide rail, 39} Carriage, 43} Base, 44 ° Z axis guide, 45 ° Z
Shaft table, 46 ‥‥ air cylinder, 47 ‥‥ rod,
48 ° stopper, 50 ° positioning unit, 51 °
‥ Y axis table, 52 ‥‥ X axis table, 53 ‥‥ θ axis table, 54 ‥‥ Mounting plate, 55 ‥‥ Z axis guide, 5
6 ‥‥ Z axis table, 58 ‥‥ ball screw, 60 ‥‥ board mounting jig, 61 ‥‥ board, 65, 66 ‥‥ support,
67 ‥‥ fixed guide, 68 ‥‥ base, 69 ‥‥ movement guide, 70 ‥‥ conveyor belt, 73, 74 ‥‥ arm, 75, 76 ‥‥ support member, 77, 78 ‥‥ holding claw,
81 ‥‥ carry-in conveyor, 82 ‥‥ carry-out conveyor, 85 ‥
{Cylinder, 86} Correction pin, 91, 92} Hinge, 93, 94 {Air cylinder, 95, 96} Sliding plate, 98} Sliding plate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C035 AA06 FA30 FA32 FB24 FB27 FB33 FC08 FC09 FD05 FD22 FD29 2C250 FA06 FB12 5E319 BB05 CD29 GG15

Claims (13)

[Claims] 1. A screen printing apparatus in which a work is superposed on a lower surface of a screen and a paste-like substance is printed on the surface of the work, wherein the screen and the work are vertically separated from each other; An image recognition camera that recognizes an image of the surface of the work, and a horizontal moving unit that moves the image recognition camera between the screen and the work, wherein the screen and the work are vertically separated from each other. A screen printing apparatus, wherein the image recognition camera is moved between the screen and the work in the state to recognize an image of a surface of the work. 2. The screen printing apparatus according to claim 1, wherein the image recognition camera recognizes an alignment mark of the work. 3. The screen printing apparatus according to claim 1, wherein the image recognition camera recognizes an image on a lower surface of the screen. 4. A position adjusting means for adjusting a relative position between the screen and the work in a horizontal direction, wherein a relative position between the screen and the work in a horizontal direction is determined based on image recognition of the image recognition camera. The screen printing apparatus according to claim 1, wherein the adjustment is performed. 5. A screen printing apparatus in which a work is superposed on a lower surface of a screen and a paste-like substance is printed on the surface of the work. A screen printing apparatus comprising: a guide unit extending in a substantially horizontal direction; and an image recognition camera supported by the guide unit so as to be movable in a horizontal direction, and recognizing an image of a surface of the work. 6. A screen printing apparatus in which a work is superposed on a lower surface of a screen and a paste-like substance is printed on the surface of the work, a support base which stands substantially vertically, and a support base provided on the support base. A screen printing apparatus comprising: a guide unit extending substantially in a horizontal direction; and a cleaning unit supported by the guide unit so as to be movable in a horizontal direction, and cleaning a lower surface of the screen. 7. A screen printing apparatus in which a work is superposed on a lower surface of a screen and a paste-like substance is printed on the surface of the work, wherein the support base is provided substantially upright, and provided on the support base. Guide means extending in a substantially horizontal direction, supported by the guide means so as to be movable in the horizontal direction, and moving while pressing the paste-like substance on the screen to print the paste-like substance on the work. And a squeegee. 8. The apparatus according to claim 5, wherein said guide means is arranged so as to extend in parallel with a direction in which said workpiece is transported.
The screen printing device according to claim 6. 9. The screen according to claim 5, wherein said guide means is a pair of guide rails arranged vertically on said support base so as to be substantially parallel to each other. Printing device. 10. The image recognition camera, the cleaning unit, or the squeegee is cantilevered by the guide means, and the end of the screen in the width direction opposite to the support base is a free end. The screen printing apparatus according to claim 5, 6 or 7, wherein 11. A screen printing apparatus in which a work is superposed on a lower surface of a screen and a paste-like substance is printed on the surface of the work. Guide means extending in a substantially horizontal direction, an image recognition camera for recognizing an image on the surface of the work, and a cleaning unit for cleaning a lower surface of the screen, wherein both the image recognition camera and the cleaning unit are provided. A screen printing apparatus, which is guided by the guiding means. 12. The screen printing apparatus according to claim 1, wherein said paste-like substance is cream solder. 13. The screen printing apparatus according to claim 1, wherein the work is a circuit board.