JPH09122554A - Paste applying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply and plot with high accuracy at high speed a paste pattern of a desired shape at a desired position on a substrate. SOLUTION: A substrate 7 is mounted opposite to a nozzle 1 on an adsorption base 13, and while paste held in a paste holding cylinder 2 is discharged onto the substrate 7 from the nozzle 1, the substrate 7 is moved in the x-axis direction and in the y-axis direction according to the rotation of ball screws 20, 21, thereby plotting a paste pattern of a desired shape on the substrate 7. On the adsorption base 13, a mark 19 for measuring the thermally extended and contracted quantity is provided. While monitoring it by an image recognizing camera 11a, the ball screws 20, 21 are rotated by a prescribed quantity to measure a deviation of the actual position of the mark 19 for measuring the thermally extended and contracted quantity moved by this rotation from a position of the mark 19 for measuring the appropriate thermally extended and contracted quantity by the rotation of the desired quantity of the ball screws 20, 21. According to this deviation, the rotated quantity of the ball screws 20, 21 for a moving distance of the attraction base 13 is corrected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paste applicator, and more particularly to a substrate mounted on a table and the nozzle according to the rotation of a ball screw while ejecting the paste from the nozzle. The present invention relates to a paste applicator in which a paste pattern having a desired shape is applied and drawn on the substrate by changing the relative positional relationship between

[0002]

2. Description of the Related Art A substrate mounted on a table is opposed to a nozzle fixed to the tip of a paste storage cylinder in which the paste is stored, and while the paste is discharged from a paste discharge port of the nozzle, the nozzle and the substrate are separated from each other. By using at least one of them in the X- and Y-axis directions with respect to the other to change the relative positional relationship between them, an ejection drawing technique for applying a paste on a substrate in a desired pattern is used. In such a paste applicator, for example, a table equipped with a nut is installed so as to be freely slidable on a linear guide, and a ball screw screwed into this nut is rotated to rotate the ball screw of the table. Instead of linear movement, the relative positional relationship between the nozzle and the substrate is changed.

An example of such a paste applicator is described in, for example, Japanese Patent Application Laid-Open No. 2-52742, and according to this, an insulating substrate is used as a substrate, and paste is ejected from the tip of the nozzle onto the insulating substrate. A desired resistance paste pattern is formed on the insulating substrate by discharging the resistance paste from the outlet.

[0004]

By the way, in the above-mentioned prior art, when the coating speed is increased in order to improve the productivity, for example, friction occurs between the ball screw driving the table and the nut. The temperature of the ball screw rises and the ball screw expands in the lengthwise direction as well, so that the entire length of the ball screw is extended.

On the other hand, the relative positional relationship between the nozzle and the substrate, that is, the amount of movement of the table on which the substrate is placed is determined by the amount of rotation of the ball screw.
When the ball screw extends, the actual lead of the ball screw, that is, the amount of driving (moving amount) of the table with respect to the amount of rotation of the ball screw increases, and it becomes impossible to obtain a paste pattern having a desired shape. In order to prevent such expansion and contraction of the ball screw, there is no choice but to slowly move the table.

In this way, the position on the substrate for coating and drawing and the shape of the pattern are set by the position information, and the ball screw is rotated based on the position information to move between the table and the nozzle. In the paste applicator configured to change the relative positional relationship, when the paste pattern is drawn at high speed, there is a problem that the drawn paste pattern cannot be sufficiently accurate.

An object of the present invention is to solve the above problems and provide a paste coating machine capable of coating and drawing a paste pattern having a desired shape at a desired position on a substrate with high accuracy and at high speed. To do.

Another object of the present invention is to apply and draw a paste pattern having a desired shape at a desired position on a substrate with high accuracy and at high speed regardless of the ambient temperature at the start of application and drawing. An object of the present invention is to provide a paste coating machine capable of performing the above.

[0009]

In order to achieve the above object, the present invention changes the rotation of a ball screw into a rectilinear motion while discharging the paste contained in a paste container from a nozzle onto a substrate. In a paste coating machine configured to draw a paste pattern having a desired shape on the substrate by moving at least one of the nozzle and a table on which the substrate is used as a moving member in any direction, the movement is performed. Storage means for providing a mark on the member, and storing information indicating the relationship between the position of the moving member and the rotation amount of the ball screw for drawing the paste pattern of the desired shape on the substrate. Measuring means for measuring the amount of expansion and contraction of the ball screw by detecting the amount of movement of the mark accompanying the movement of the moving member, and the storage means in accordance with the measurement data by the measuring means. Correcting means for correcting the amount of rotation of the ball screw with respect to each position of the moving member in the stored information, and moving the moving member in accordance with the information corrected by the correcting means, the substrate Drawing means for drawing the desired paste pattern on the top.

With such a structure, when the moving member is the table, for example, the position of the table in the X and Y axis directions due to the thermal expansion of the ball screw for driving the table is determined from the moving amount of the mark provided on the table. The change is measured, and the rotation amount of the ball screw corresponding to the position information of the paste pattern is corrected from this measurement data. Therefore, the relative movement of the nozzle and the substrate does not change even when the ball screw is thermally expanded, and the paste pattern can be continuously applied and drawn in a desired shape in a desired shape with high accuracy. You can

[0011]

DETAILED DESCRIPTION OF THE INVENTION The embodiments of the present invention will be described below.

FIG. 1 is a schematic perspective view showing an embodiment of a paste applicator according to the present invention, in which 1 is a nozzle, 2 is a paste container (or syringe), 3 is an optical rangefinder,
4a is a Z-axis table, 4b is a camera support, 5 is an X-axis table, 6 is a Y-axis table, 7 is a substrate, 8 is a θ-axis table, 9 is a mount, 10 is a Z-axis table support, and 11a. Is an image recognition camera, 11b is a lens barrel, 12 is a nozzle support,
13 is a suction table for the substrate 7, 14 is a control device, and 15a to 15
c is a servo motor, 16 is a monitor, 17 is a keyboard,
18 is an external storage device, 19 is a mark for measuring thermal expansion and contraction, 2
Reference numeral 0 is an X-axis ball screw, and 21 is a Y-axis ball screw.

In the figure, an X-axis table 5 is fixed on a gantry 9, and an X-axis ball screw rotatable by a servomotor 15b is provided in the X-axis table 5 extending in the X-axis direction. A Y-axis table 6 is mounted on the X-axis table 5 so as to be movable in the X-axis direction by a linear guide provided therein, and a nut (not shown) provided on the bottom surface of the Y-axis table 6 is attached to the X-axis table 6. Axial bolt screw 20 is screwed. Further, on the Y-axis table 6, the servo motor 1
A Y-axis ball screw 21 rotatable by 5c is provided extending in the Y-axis direction. Then, further, on the Y-axis table 6, by a linear guide provided there,
A θ-axis table 8 is mounted so as to be movable in the Y-axis direction, and a Y-axis bolt screw 21 is screwed into a nut (not shown) provided on the bottom surface of the θ-axis table 8. A suction table 13 is fixed on the θ-axis table 8. This suction table 1
The substrate 7 is fixed on the substrate 3 by vacuum suction so that each side thereof is parallel to the X and Y axis directions. The θ-axis table 8 also has an upper portion to which the suction base 13 is fixed and a Y-axis table.
The shaft table 6 includes a portion attached to the linear guide, and the upper portion is rotatable with respect to the lower portion in the θ-axis direction around its center position.

The substrate 7 mounted on the suction table 13 can be moved in the X and Y axis directions by the control drive of the servomotors 15b and 15c by the controller 14. That is,
When the servomotor 15b is driven by the controller 14, the X-axis ball screw 20 rotates and the Y-axis table 6 moves to the X-axis.
When the substrate 7 is moved in the axial direction to move in the X-axis direction and the servo motor 15c is driven, the Y-axis ball screw 21 is rotated, the θ-axis table 8 is moved in the Y-axis direction, and the substrate 7 is moved to the Y-axis. Move in the axial direction. Therefore, when the servomotors 15b and 15c are driven by the control device 14, the substrate 7 passes through the X-axis table 5 and the Y-axis table 6 in an arbitrary direction in a plane parallel to the gantry unit 9. You will move only a distance. Further, the θ-axis table 8 is rotated in the θ-axis direction around its center position by the servo motor 15d shown in FIG.

A Z-axis table support portion 10 is installed on the pedestal portion 9, and the Z-axis table support portion 10 is installed in the Z-axis direction (vertical direction).
A Z-axis table 4a is attached so as to be movable.
The nozzle 1, the paste storage cylinder 2, and the optical distance meter 3 are mounted on the Z-axis table 4a. The control device 14 controls and drives the Z-axis table 4a in the Z-axis direction (vertical direction). That is, the servo motor 15a
Is driven by the controller 14, the Z-axis table 4
a moves in the Z-axis direction, and accordingly, the nozzle 1, the paste container 2, and the optical distance meter 3 move in the Z-axis direction.

The nozzle 1 is connected to the paste storage cylinder 2 via a nozzle support tool 12 attached to the tip of the paste storage cylinder 2, and the nozzle support tool 12 allows the optical displacement meter 3 as a range finder. It is positioned near the lower side of.

FIG. 2 is an enlarged perspective view showing the paste storage cylinder 2 and the optical distance meter 3 in FIG.
Reference numeral 12a is a connecting portion, and the portions corresponding to those in FIG.

In FIG. 1, the optical rangefinder 3 is a nozzle 1
The distance between the tip (lower end) of the paste ejection port and the upper surface of the substrate 7 is measured by non-contact and triangulation.

That is, the lower end portion of the optical distance meter 3 is cut in a triangular shape, and two inclined surfaces facing each other are formed in the cut portion, and one light emitting element is provided on one of these inclined surfaces.
On the other hand, a plurality of light receiving elements are provided respectively. The nozzle support 12 is attached to the tip of the paste storage cylinder 2, the connecting portion 12a extends below the cut portion of the optical distance meter 3, and the nozzle 1 is attached to the lower surface of the tip.

The light L emitted from the light emitting element provided in the cut portion of the optical distance meter 3 illuminates the position below the nozzle 1 on the substrate 7 (FIG. 1), as shown by the alternate long and short dash line.
One of the plurality of light receiving elements receives the reflected light from the light receiving element, and the distance (distance) between the paste ejection port of the nozzle 1 and the substrate 7 is determined from the position of the received light receiving element.

The paste discharge port at the tip of the nozzle 1 and the substrate 7
When the distance between the upper surface of the nozzle 1 and the upper surface of the nozzle is the correct distance, the positional relationship between the nozzle 1 and the optical distance meter 3 is adjusted so that the light L from the light emitting element irradiates the surface of the substrate 7 directly below the nozzle 1. The arrangement of the light emitting element and the light receiving element in the optical distance meter 3 is set. Therefore, when the distance between the paste discharge port of the nozzle 1 and the substrate 7 changes, the irradiation position of the light L from the light emitting element deviates from the position directly below the nozzle 1 on the substrate 7, and as a result, the light receiving element The light receiving status changes. Thereby, the distance between the paste discharge port of the nozzle 1 and the substrate 7 can be measured.

As will be described later, when the substrate 7 is moved in the X and Y axis directions to form a paste pattern, the light L from the light emitting element is irradiated on the substrate 7 at the irradiation point (hereinafter referred to as measurement point). When S passes across the already formed paste pattern, an error occurs in the measured value of the distance between the paste discharge port of the nozzle 1 and the surface of the substrate 7 by the optical distance meter 3 by the thickness of the paste pattern. Therefore, in order to prevent the measurement point S from crossing the paste pattern as much as possible,
It is advisable to set the measurement point S to a position that is displaced obliquely with respect to the X and Y axes from the paste dropping point (hereinafter referred to as the application point) from the nozzle 1 onto the substrate 7.

When the paste in the paste storage cylinder 2 is used up, the unitized paste storage cylinder 2, the nozzle support 12, and the nozzle 1 are replaced (this replacement is called nozzle replacement), and coating is performed. The nozzle 1 is attached so that the point coincides with a certain set position where the paste is to be applied on the substrate 7. However, due to variations in the attachment accuracy of the paste storage cylinder 2, the nozzle support 12, and the nozzle 1, it is possible to replace the nozzle. The position of the nozzle 1 may change before and after.

However, the application point has an allowable range (ΔX, Δ) of a preset size centering on the set position to be actually applied.
When it is in Y), it is assumed that the nozzle 1 is properly attached. However, ΔX is the width of the allowable range in the X-axis direction,
ΔY is also the width in the Y-axis direction.

Returning to FIG. 1, the amount of thermal expansion and contraction for measuring the expansion and contraction of the X-axis ball screw 20 and the Y-axis ball screw 21 at a position on the suction table 13 which is not hidden by the substrate 7 mounted thereon. A measurement mark 19 is provided.

Further, an image recognition camera 11a having a lens barrel 11b is attached to the Z-axis table support portion 10 to recognize the position of the substrate 7 when the initial position is set and after the nozzle 1 is replaced. Position confirmation, nozzle 1 interval measurement,
It is used for reading the thermal expansion / contraction amount measurement mark 19 and the like. The image data is supplied to the control device 14 and used for controlling each part. Further, the monitor 16 displays such images and input data of the keyboard 17.

The control device 14 is supplied with data from the optical range finder 3 and the image processing device (FIG. 3) through the external interface (FIG. 3), and in response to this, the servo motors 15a to 15d (servo). For the motor 15d, see FIG.
Drive). Also, these servo motors 15
motors 15a from the encoders provided on a to 15d
The data about the driving conditions of 15 d to 15 d
Will be fed back.

In this structure, the rectangular substrate 7
When the substrate 7 is placed on the suction table 13, the suction table 13 holds the substrate 7 by vacuum suction. Then, by rotating the θ-axis table 8, the orientation is set so that each side of the substrate 7 is parallel to each of the X and Y axes. Thereafter, the servo motor 15a is driven and controlled based on the measurement result of the optical distance meter 3, so that the Z-axis table 4a moves downward, and the paste discharge port of the nozzle 1 and the substrate 7 are moved from above the substrate 7. It is lowered until the distance between the surface and the surface becomes the specified distance.

After that, the paste supplied from the paste container 2 through the nozzle support 12 is discharged from the paste discharge port of the nozzle 1, and together with this, the servomotor 1
The X-axis table 5 and the Y-axis table 6 are appropriately moved by the drive control of 5b and 15c, whereby the paste is applied on the substrate 7 in a pattern of a desired shape.

The paste pattern to be formed is X,
It can be converted by the distance in the Y-axis direction. Therefore, when the data for forming the pattern of the desired shape is input from the keyboard 17, the control device 14 sends this data to the servo motor 1.
Drawing is automatically performed by converting the number of pulses given to 5b and 15c and outputting a command.

FIG. 3 is a block diagram showing a specific example of the control device 14 in FIG. 1, in which 14a is a microcomputer, 14b is a motor controller, 14cb is an X-axis driver, 14cc is a Y-axis driver, and 14cd is a θ-axis. A driver, 14ca is a Z-axis driver, 14d is an image processing device, 14e is an external interface, 15d is a θ-axis motor, E is an encoder, 19 is a paste pattern,
Parts corresponding to those in FIG. 1 are denoted by the same reference numerals.

In the figure, the microcomputer 14a includes a ROM storing a processing program and an RA storing various data.
It has a built-in M and a CPU for calculating various data.

From the keyboard 17, data for designating the shape of the paste pattern to be drawn, data for designating the distance between the nozzle 1 and the substrate 7, and the like are input, and via the external interface 14e. It is supplied to the microcomputer 14a. In the microcomputer 14a, these data are processed using the CPU and RAM according to the software program stored in the ROM.

The motor controller 14 is operated in accordance with the data designating the shape of the paste pattern thus processed.
b is controlled, X-axis driver 14cb, Y-axis driver 1
The X-axis motor 15b, the Y-axis motor 15c, or the θ-axis motor 15d is rotationally driven by the 4 cc or θ-axis driver 14cd. Further, encoders E are provided on the rotary shafts of these motors, whereby the rotation amounts (driving operation amounts) of the respective motors are detected and the X-axis drivers 14cb, Y are detected.
The X-axis motor 15b, the Y-axis motor 15c, or the θ-axis motor 15d is fed back to the microcomputer 14a via the axis driver 14cc or the θ-axis driver 14cd or the motor controller 14b so that the X-axis motor 15b, the Y-axis motor 15c, or the θ-axis motor 15d accurately rotates by the rotation amount specified by the microcomputer 14a. Controlled by. As a result, the desired paste pattern 19 is drawn on the substrate 7.

During drawing of the paste pattern, the measurement data of the optical displacement meter 3 is converted into digital data by an AD converter (not shown), and the external interface 14e.
The data is supplied to the microcomputer 14a via the, and the comparison processing with the data designating the distance between the nozzle 1 and the substrate 7 is performed here. When the surface of the substrate 7 has undulations, this is detected by the microcomputer 14a based on the input data, the motor controller 14b is controlled, and the Z-axis motor 15a is rotationally driven by the Z-axis driver 14ca.
As a result, the paste storage cylinder 2 (FIG. 1) is displaced in the vertical direction to keep the distance between the paste discharge port of the nozzle 1 (FIG. 2) and the surface of the substrate 7 constant. An encoder E is also provided on the rotary shaft of the Z-axis motor 15a, and the rotation amount of the Z-axis motor 15a is fed back to the microcomputer 14a via the Z-axis driver 14ca and the motor controller 14b. 15a is controlled to rotate accurately by the amount of rotation designated by the microcomputer 14a.

Various data input from the keyboard 17 and various data generated by being processed by the microcomputer 14a such as data of the paste pattern to be drawn and data at the time of nozzle replacement are stored in the RAM built in the microcomputer 14a. It

FIG. 4 is a diagram showing the measurement state of the amount of thermal expansion and contraction of the X-axis ball screw 20 and the Y-axis ball screw 21 in FIG. 1. Specifically, each ball screw 20 for driving the table,
21 shows how the thermal expansion / contraction amount measuring mark 19 provided on the suction table 13 is displaced within the visual field BF of the image recognition camera 11a when the thermal expansion / contraction of 21 occurs during the operation of the apparatus.

In FIG. 1, the ball screws 20 and 21 are
As described above, heat is generated due to friction between the threaded portion and the nut with which the screw is screwed, and the ball screws 20 and 21 expand or contract in response to the heat generation. Here, the ball screws 20 and 21 are configured to extend in the direction opposite to the motor mounting end in order to allow expansion and contraction freely (that is, to allow expansion and contraction to escape).

The substrate 7 placed on the suction table 13 maintains the same size regardless of the expansion and contraction of the ball screws 20 and 21. The position and length of the paste applied to the substrate 7 are set by the distance from the reference position of the suction table 13, and the servo motor 1
It is given by the rotation amount of 5b and 15c. Ball screw 20,
If the length of 21 is unchanged, the designated rotation amount becomes the movement distance of the suction table 13 as it is.
When 1 expands and contracts, even if the suction table 13 is moved by the designated rotation amount, the substrate 7 moves to a position different from the set position in the X-axis and Y-axis directions, and a deviation occurs from the set position. .

This means that when the paste pattern is formed, the paste application position is displaced, and the paste pattern cannot be accurately formed at a desired position. Therefore, it is necessary to grasp the thermal expansion and contraction and correct the rotation amount of the servo motors 15b and 15c.

Therefore, as shown in FIG. 4, in the visual field BF of the image recognition camera 11a (FIG. 1), the suction table 13
It is assumed that the center of the thermal expansion / contraction amount measurement mark 19 provided in (FIG. 1) is located at the position (X ₀ , Y ₀ ) from the origin OP of the visual field BF. The center position of the thermal expansion / contraction amount measurement mark 19 is
The barycenter of the image of the thermal expansion / contraction amount measurement mark 19 read by the image recognition camera 11a is obtained by image processing with the image processing device 14d (FIG. 3). The obtained data representing the center position of the thermal expansion / contraction amount measuring mark 19 is stored in the RAM built in the microcomputer 14a (FIG. 3).

By driving the servo motors 15b and 15c, the center of the thermal expansion / contraction amount measuring mark 19 is moved from the origin OP of the visual field BF to the positions [X ₀ + DX], [Y ₀ + DY]. Suppose it is rotated to. Here, the relationship between the distances DX and DY and the rotation amounts of the servo motors 15b and 15c is set at an arbitrary reference temperature, and is set such that the thermal expansion / contraction amount measurement mark 19 does not deviate from the visual field BF. However, due to the extension of the ball screws 20 and 21, the distance dX,
Mark 19 for measuring thermal expansion and contraction at a position displaced by a distance of dY
If the center of moves, the distance [DX + d
X] and [DY + dY] are obtained by reading the thermal expansion / contraction amount measurement mark 19 with the image recognition camera 11a and performing image processing with the image processing device 14d. When moving the thermal expansion / contraction amount measuring mark 19, the servo motor 15 is used.
b and 15c may be driven simultaneously or individually.

In this case, the distances dX and dY are the ball screw 2
This is due to the elongation of 0, 21, and this elongation cannot be restored. Therefore, in order to bring the center of the thermal expansion / contraction amount measuring mark 19 to the position of the distance DX, DY, the servo motor 15b is used. , 15c, it is necessary to reduce the amount of rotation of the ball screws 20, 21. However, since the distances dX and dY cannot be obtained during the painting and drawing of the paste, the marker
The amount of rotation of the ball screws 20 and 21 is corrected from the amount of movement of the hook 19.

Movement set amount L of the substrate 7 in the X-axis and Y-axis directions
X and LY are the target movement amounts of the substrate 7, respectively OX and O
When the thermal expansion and contraction rates of the Y and ball screws 20, 21 in the X-axis and Y-axis directions are αx and αy, respectively, it can be expressed by the following equation.

Movement setting amount LX = (1-αx) × target movement amount OX (1) Movement setting amount LY = (1-αy) × target movement amount OY (2) where αx = dX / Dx, αy = DY / DY.

The start and end positions of the paste pattern to be applied and drawn on the substrate 7 are determined by the timing of the movement of the substrate 7 and the paste ejection from the nozzle 1. Therefore, these start and end positions are also as described above. It can be set by both formulas.

In the above equations (1) and (2), the thermal expansion and contraction rates αx and αy have a positive sign when the ball screws 20 and 21 expand, and a negative sign when they contract. I have it.

Therefore, the above formulas (1) and (2) can be applied as they are, not only when the ball screws 20 and 21 are extended by overheating but also when they are contracted by being cooled by the outside air or the like. The distance [D
It can be easily determined by comparing whether X + dX] and [DY + dY] are increasing or decreasing with the data at the previous measurement.

In the control device 14, the target movement amounts OX, O
When the data of Y and the start and end positions of the paste pattern are input from the keyboard 17, the calculation is performed by both of the above equations to obtain the suction base 13 and the movement set amounts LX and LY. The rotation amounts of the ball screws 20 and 21 corresponding to the set amounts LX and LY are obtained and stored in the RAM of the microcomputer 14a, and the substrate 7 is processed in accordance with the processing operation shown in the following flow chart. A paste pattern having a desired length is applied and drawn on the desired position on the upper side.

Hereinafter, the processing operation of the control device 14 at the time of the paste application drawing in this embodiment will be described.

In FIG. 5, when the power is turned on (step 100), first, the initial setting operation of the paste applicator is executed (step 200). This initial setting is performed as shown in FIG.

That is, in FIG. 6, the Z-axis table 4a, the X-axis table 5, the Y-axis table 6 and the θ-axis table 8 are positioned at a predetermined origin position (step 20).
1), data regarding the paste pattern, that is, data regarding the nozzle to be used, data regarding the discharge pressure of the paste relating to the height of the paste pattern, and the height of the nozzle. A setting process is performed to temporarily store data, data relating to the ejection start position of the paste, position data relating to the relationship between the paste pattern and the substrate 7 in the control device 14 (step 202). , Data setting regarding the discharge end position of the paste is performed (step 203).

The data input for these settings is the keyboard.
The input data and the like are stored in the RAM incorporated in the microcomputer 14a (FIG. 3) as described above.

When the above initial setting process (step 200) is completed, in FIG. 5, at the start of operation (ball screw 2
The position of the thermal expansion / contraction amount measurement mark 19 in the state where 0 and 21 are not thermally expanded / contracted is measured (step 300). In this position measurement, as shown in FIG. 4, after the thermal expansion / contraction amount measurement mark 19 is moved into the visual field BF of the image recognition camera 11a, the image processing device 14d causes the image recognition camera 11a to move.
The center position on the coordinates of the thermal expansion / contraction amount measurement mark 19 photographed in a (the distance from the origin OP of the visual field BF in FIG. 4 (X
₀ , Y ₀ )) is measured.

Next, the substrate 7 on which the paste pattern is to be drawn is mounted on the suction table 13 and held by suction (step 40).
0), the position of the thermal expansion / contraction amount measurement mark 19 during operation (distance [DX + dX], [DY + dY] in FIG. 4) is measured (step 500), and the thermal expansion / contraction previously measured in step 300 is performed. The difference from the coordinate position of the quantity measuring mark 19 is obtained, the data is converted into the actual length based on the equations (1) and (2), and the rotation amounts of the servo motors 15b and 15c are corrected ( Step 600).

In this step 600, the rotation amount of the servo motors 15b and 15c is collectively corrected prior to the coating and drawing of all the paste patterns coated and drawn on one substrate 7. The data obtained by this correction calculation is stored in the RAM incorporated in the microcomputer 14a. This is to prevent the paste in the paste storage cylinder 2 from deteriorating with the passage of time and failing to obtain the desired paste pattern. That is, various data required for coating and drawing are prepared in advance, and the aim is to draw a paste pattern uniformly on the substrate 7 at a stretch.

Then, the substrate preliminary positioning process (step 700) is performed, which will be described in detail with reference to FIG.

In FIG. 7, first, a positioning marker attached beforehand to the substrate 7 (FIG. 1) mounted on the suction table 13.
A picture (not shown in FIG. 1) is photographed by the image recognition camera 11a (step 701), and the position of the center of gravity (center) of the positioning mark within the visual field of the image recognition camera 11a is obtained by image processing (step 702). ). Then, the amount of deviation between the center of this field of view and the position of the center of gravity of the positioning mark is calculated (step 703), and this amount of deviation is used to move the substrate 7 to the desired position on the X-axis table 5, Y. The amount of movement of the axis table 6 and the .theta.-axis table 8 (FIG. 1) is calculated (step 704). The calculated movement amount is used for the servomotor 15
b, 15c, 15d (FIGS. 1 and 3) are converted into operation amounts (step 705), and the servomotors 15b, 15c, 15d are driven according to the operation amounts (step 70).
6). As a result, the X-axis table 5, the Y-axis table 6 and the θ-axis table 8 move to move the substrate 7 to a desired position.

With this movement, the positioning mark on the substrate 7 is again photographed by the image recognition camera 11a, and the center of gravity (center) of the positioning mark within the field of view is measured (step 707). The center of the field of view and the positioning marker
The deviation from the center of the substrate is calculated and stored as a positional deviation amount of the substrate 7 in the RAM built in the microcomputer 14a (step 708). Then, it is confirmed whether or not the displacement amount is within the allowable ranges ΔX and ΔY shown in FIG. 2 (step 70).
9). If the amount of positional deviation is within this range, this substrate preliminary positioning process (step 700) has ended, but if the amount of positional deviation is outside this range, then step 704 is performed.
Then, the series of processes described above is performed again, and the process is repeated until the positional deviation amount falls within the permissible ranges ΔX and ΔY. As a result, the substrate 7 is positioned so that the desired coating point on the substrate 7 from which the coating is to be started is within the allowable range (ΔX, ΔY) from directly below the ejection port of the nozzle 1.

Returning to FIG. 5 again, when the process of step 700 is completed as described above, the process proceeds to the paste film forming process (step 800). This is shown in FIG.
Will be described.

In FIG. 8, first, the controller 14 moves the substrate 7 to the coating start position (step 801). The movement to this starting position is performed by the ball screws 20 and 2 previously obtained.
The correction value of the thermal expansion / contraction amount measurement data for 1 is used. At this time, since the substrate 7 is positioned at the desired position by the substrate positioning process (step 700 in FIG. 4) described above, the substrate 7 can be accurately moved to the coating start position.

Further, the nozzle 1 is moved to the set height position (step 802). That is, the distance from the discharge port of the nozzle 1 to the surface of the substrate 7 is made equal to the thickness of the paste film to be formed. In response to the completion of the movement of the nozzle 1, the control device 14 causes the nozzle 1 to start the ejection of the paste from the coating start position (step 8).
03).

Next, the control unit 14 controls the optical rangefinder 3
The measured data of the distance from the paste discharge port of the nozzle 1 to the substrate 7 shown in FIG. 1 is taken in to measure the waviness of the surface of the substrate 7 (step 804), and the measurement of the optical distance meter 3 is performed. It is determined whether the position is on the paste film (step 805). For example, if the measured data of the optical distance meter 3 changes extremely or the undulation exceeds the allowable value, it is determined that the measurement position has crossed the paste film.
When the measurement position of the optical range finder 3 is not on the paste film, the corrected data for moving the Z-axis table 4a is calculated based on the measured data (step 806). Then, the height of the nozzle 1 is corrected using the Z-axis table 4a, and the position of the nozzle 1 in the Z-axis direction is maintained at the set value (step 807).

On the other hand, when it is determined that the measurement position of the optical distance meter 3 is passing over the paste film (step 8)
05), the height of the nozzle 1 is maintained at the height before this determination without performing the processing of steps 806 and 807.
Continue discharging the strike. When the measurement position is passing over a paste film having a small width, the waviness of the substrate 7 hardly changes in most cases. Therefore, if the height of the nozzle 1 is not changed, the paste is discharged. There is no change in shape, which allows
A paste pattern having a desired thickness can be drawn.

Next, the controller 14 determines whether or not the set paste ejection has been completed (step 80).
8). If it is finished, the paste discharge is finished (step 80).
9) If not finished, paste ejection is continued.
Further, it is determined whether or not the set pattern operation is completed (step 810). This process is a process operation of determining whether or not the end point of the paste pattern which has been continuously drawn has been reached. This end point is not necessarily the end point of the pattern of the entire desired shape drawn on the substrate 7.

If it is not the end point, the process returns to the substrate surface waviness measurement process (step 804) and the above series of processes is repeated. In addition, when the measurement position has finished passing over the paste film,
The process returns to the original nozzle height correction process (steps 806 and 807).

In this way, when the paste film is formed over the entire pattern of the desired shape (step 810), the nozzle 1 is raised (step 811).
This paste film forming process (step 800) is completed.

Now, when the paste film forming process (step 800) of the desired pattern is completed in this way,
Returning to FIG. 5, the substrate 7 placed and held on the suction table 13
Since the coating and drawing operation of the paste has been completed, the substrate 7 is discharged from the suction table 13 (step 90
0), it is determined whether or not all the processes before step 900 are stopped (step 1000). That is, in the case of applying and drawing a paste on a plurality of substrates 7 with the same pattern,
Returning to step 400, the processes up to step 900 are repeatedly executed. As a result, mass productivity is improved, and the cost of manufactured products can be reduced.

As described above, in this embodiment, since the thermal expansion and contraction of the ball screws 20 and 21 for driving the table are simply measured for each substrate and then the paste pattern is drawn, the drawn paste pattern is drawn. The position and size of the connector can be precisely desired.

Further, the thermal expansion and contraction of the ball screws 20 and 21 are measured, and based on the measurement results, the ball screws 20 and 21 are
Since the rotation amount of the ball screw 21 is corrected, no matter how the lengths of the ball screws 20 and 21 are changed by rotating at high speed, the position of the paste pattern drawn on the substrate 7 And the dimensions are precisely the desired one.

If the thermal expansion and contraction of the ball screws 20 and 21 does not change significantly for each substrate 7, the substrate mounting process (step 400) and the mark measurement process during operation (step 5) in FIG.
00), as shown in FIG. 9, a set number counting process (step 450) for confirming the number of processed substrates 7 is provided, and only when the set number is reached, during the operation described in FIG. The mark measurement process (step 500) and the data conversion process (step 600) are performed. If the set number of times is not reached, the processes of steps 500 and 600 are omitted and the substrate mounting process (step 400) is performed. ) To the substrate pre-positioning process (step 700), which can speed up the process.

In the above embodiment, the thermal expansion / contraction amount measuring mark 19 is provided on the adsorption table 13 on the θ-axis table 8 in FIG. 1, but the substrate 7 is attached to the θ-axis table 8. When the fixing means is provided, the thermal expansion / contraction amount measuring mark 19 may be provided on the θ-axis table 8. Further, in the case where the θ-axis table 8 is not provided, Y
The thermal expansion and contraction amount measuring mark 19 may be provided on the suction table 13 or the like on the shaft table 6. In short, the thermal expansion / contraction amount measuring mark 19 may be provided as long as it moves in the X and Y axis directions, and thus the thermal expansion / contraction amount measuring mark 19 is generically referred to. A table provided with a mark 19 for measuring the amount of thermal expansion and contraction. The shape of the thermal expansion / contraction amount measuring mark 19 may be any shape as long as its center position can be clearly and easily specified by image processing, and is not limited to the circular shape as shown in FIG. Absent.

Further, in order to shorten the time required for the coating machine initial setting process (step 200) in FIG. 5, the external storage device 18 connected via the external interface 14e (FIG. 3) is used. The data stored in advance in the RAM is stored in the RAM in the microcomputer 14a (FIG. 3).
(FIG. 3).

Further, the measured data and the like are stored in the external storage device 18 (FIGS. 1 and 3) to be stored in the micro computer.
It is also possible to increase the storage capacity of the RAM built in the data 14a or store the data about the measurement result in the external storage device 18 for the convenience of later use.

Further, the suction table 13 on which the substrate 7 is placed is fixed, and the nozzle 1 is moved along with the paste housing cylinder 2 and the optical distance meter 3 in the X and Y axis directions. In the paste applicator, the above-mentioned thermal expansion / contraction amount measuring mark 19 is provided on the nozzle 1, the paste storage cylinder 2, the optical distance meter 3 or their supports. As a result, the same effect can be obtained by performing the same processing operation as that in the case where the thermal expansion / contraction amount measuring mark 19 is provided on the suction table 13 or the like.

[0076]

As described above, according to the present invention,
It is possible to apply and draw a paste pattern having a desired shape at a desired position on the substrate with high accuracy and at high speed.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a paste coating machine according to the present invention.

FIG. 2 is a perspective view showing a positional relationship between the nozzle shown in FIG. 1 and an optical distance meter.

3 is a block diagram showing a specific example of a control device in the paste applicator shown in FIG.

FIG. 4 is a diagram for explaining the situation of thermal expansion / contraction measurement of a ball screw in the embodiment shown in FIG.

5 is a flowchart showing a specific example of the overall operation of the exemplary embodiment shown in FIG.

FIG. 6 is a flowchart showing an initial setting process in the flowchart in FIG.

FIG. 7 is a flowchart showing a substrate preliminary positioning process in the flowchart in FIG.

8 is a flowchart showing a paste film forming process in the flowchart in FIG.

9 is a flowchart showing another specific example of the overall operation of the embodiment shown in FIG.

[Explanation of symbols]

 1 Nozzle 2 Paste Storage Cylinder 3 Optical Distance Meter 4a Z-axis Table 5 X-axis Table 6 Y-axis Table 7 Substrate 8 θ-axis Table 9 Stand 10 Z-axis Table Support 11a Image recognition camera 12 Nozzle support 13 Suction table 14 Control device 14a Microcomputer 14b Motor controller 14ca-14cd driver 14d Image processing device 14e External interface 15a-15d Servomotor 16 image Monitor 17 Key board 18 External storage device 19 Thermal expansion / contraction measurement mark 20 X-axis ball screw 22 Y-axis ball screw

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Fukuo Yoneda Fukuo Yoneda 5-2 Koyodai, Ryugasaki, Ibaraki Hitachi Techno Engineering Co., Ltd. R & D Laboratory (72) Yukihiro Kawasumi 5-2 Koyodai, Ryugasaki, Ibaraki Hitachi Techno Engineering Co., Ltd. R & D Laboratory (72) Inventor Yoshihiro Nakagami 5-2 Koyodai, Ryugasaki, Ibaraki Hitachi Techno Engineering Co., Ltd., Ryugasaki Plant

Claims (4)

[Claims] 1. A substrate is placed on a table so as to face a paste discharge port of a nozzle, and the paste stored in a paste storage cylinder is discharged from the paste discharge port onto the substrate while In a paste coating machine configured to draw a paste pattern of a desired shape on the substrate by changing the rotation into a linear movement and moving at least one of the nozzle and the table in any direction using a moving member. A mark is provided on the moving member, and information indicating the relationship between the position of the moving member for drawing the paste pattern of the desired shape on the substrate and the rotation amount of the ball screw is stored. According to the storage means, the measuring means for detecting the amount of movement of the mark accompanying the movement of the moving member to measure the amount of expansion and contraction of the ball screw, and the measuring data by the measuring means. Correction means for correcting the amount of rotation of the ball screw with respect to each position of the moving member in the information stored in the storage means, and moving the moving member according to the information corrected by the correcting means And a drawing means for drawing the desired paste pattern on the substrate. 2. The correction unit according to claim 1, wherein the correction unit obtains the expansion / contraction ratio of the ball screw from the measurement data obtained by the measuring unit, and draws a paste pattern having a desired shape at a desired position on the substrate according to the expansion / contraction ratio. As described above, the paste applicator, which corrects the rotation amount of the ball screw in the information stored in the storage means. 3. The correction unit according to claim 1, wherein when the plurality of paste patterns are drawn on the substrate, the correction unit collectively corrects the rotation amount of the ball screw for each of the paste patterns, and the correction is performed. The drawing means stores the corrected respective rotation amounts stored in the storage means and rotates the ball screw by the respective rotation amounts. By so doing, a paste applicator characterized in that a plurality of paste patterns are continuously drawn on the substrate. 4. The measuring device according to claim 3, wherein the measuring means measures the expansion and contraction of the ball screw after drawing an arbitrary number of paste patterns for drawing the next arbitrary number of paste patterns. A paste applicator characterized in that