JP2908490B2 - Workpiece positioning method for mask in screen printing machine - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method of aligning a work with respect to a mask in a screen printing machine (hereinafter, also simply referred to as “alignment method”), and more specifically, printing by a screen printing machine. The present invention relates to a method of adjusting the position of a work (substrate to be printed) placed on a stage so as to have a predetermined positional relationship with respect to a printing mask by adjusting the position of the stage.

(Prior art) In printing by a general screen printing machine, a mask provided with a printing pattern corresponding to a work is used.
The work is positioned so as to be at an appropriate position, and after this setup operation, the work is sequentially printed.

By the way, for example, when the work is a ceramic substrate for an IC package and a conductor pattern is printed, extremely high printing accuracy is required. The following is an example of an alignment method employed in such a case. The alignment method will be described with reference to FIG.

First, a work W is placed at a predetermined position on a stage as a printing table (not shown), and a transparent polyester film F is attached to the printing surface by bonding or the like. After a while
A test print T is performed thereon.

Then, in the operator, the position P to be printed on the work W
Is shifted from the position of the test print T, that is, the base point B of the work W corresponding to the base point O of the test print T
The amounts of deviation, X, Y, and θ of the horizontal displacement, the front-rear direction, and the angular displacement are measured.

Then, wipe off the test print T by wiping it with a cloth or the like,
While reading the provided gauge (not shown) according to the amount of each measured deviation, using a micrometer head (not shown) etc., turn the knob to finely move or rotate the stage back and forth, left and right, Work W
Is carefully adjusted so that the print position P is a position corresponding to the portion of the test print T, that is, the position matching the print pattern of the mask. In this way, by repeating this operation many times, the work W is set to the correct position with respect to the mask, and then the polyester film F is peeled from the work W,
Printing is performed sequentially.

That is, conventionally, test printing is performed on the polyester film F stuck on the work W, and if, for example, the work is shifted to the right by 2 mm with respect to the position of the test print T, the operator measures the shift, and thereafter, The work is moved to the left correspondingly using a micrometer head or the like depending on the feeling. Then, by repeating the operations such as test printing and positioning again, the desired position was gradually approached.

(Problems to be Solved by the Invention) In the above-mentioned conventional alignment method, the work is adjusted by moving the work in accordance with each of the above-mentioned shifts. At this adjustment, the work W and the polyester film F move together. Would. Therefore, it is impossible to visually match the workpiece W to the portion of the test print T of the polyester film F. For this reason, the operator is forced to make adjustments while visually observing the amount of this shift, making the work difficult to position.

In addition, since this operation needs to be performed repeatedly, a considerable amount of time is required. Particularly, a beginner tends to perform an erroneous operation such as moving a knob. Conventionally, the time required for this work is about 15 minutes for a skilled worker, and about twice as long for a beginner. For example, the work time is extremely low, and the work efficiency varies significantly depending on the skill level.

In addition, in the above-described conventional method, in order to prevent overlapping with the reprinting, it is necessary to erase the previous reprinting each time. In addition, the repetition of the test printing increases consumption of expensive ink and causes a cost increase.

In particular, in the case of high-mix low-volume production, the troublesome work described above is frequently repeated with a small number of lots for each kind, so that the ratio of the setup work to the original printing work becomes extremely large. Had to work.

In view of these problems to be solved, an object of the present invention is to provide a simple and short-time alignment method by performing test printing once on a transparent sheet for test printing such as a polyester film. .

(Means for Solving the Problems) In order to achieve the above object, the present invention adjusts the position of a stage mounted on a stage with respect to a printing mask of a screen printing machine by adjusting the position of the stage. In the alignment method, a transparent test printing transparent sheet for test printing is mounted on a mounting frame provided with positioning pins, and the mounting frame on which the test printing transparent sheet is mounted is mounted on the mounting frame for positioning. By pinning the pin outside the stage, the test print transparent sheet is interposed on the printing surface of the work in a state where the work is relatively movable, and under this condition, Perform test printing on the transparent sheet for test printing, and then visually check the work through the transparent sheet for test printing, and apply the work to the position of the test printing. Printing position is to that and adjusting the position of said stage to be compatible.

(Operation) In the present invention, with the above-described configuration, even after performing trial printing on the trial-printing transparent sheet and then adjusting the position of the work by moving the stage, the trial printing position remains at that position. Still and move. That is, only the work moves without moving the test print.

Therefore, the operator only needs to adjust the position of the stage so that the printing position becomes accurate while watching the movement of the work through the transparent sheet for test printing while viewing the test print pattern.

Thus, the time required for alignment is greatly reduced,
In addition, the printing can be performed irrespective of the skill level of the operator, and the printing cost can be reduced.

After the completion of the alignment, the stage is locked at that position, the transparent sheet for test printing is removed, and the original printing operation is started.

Furthermore, in the above-described means, since the transparent sheet for test printing is attached to the mounting frame and pinned to intervene on the print surface of the work, it may occur that the work is again positioned with respect to the mask. Also, by resetting the removed mounting frame with the transparent sheet, that is, pinning it again, the position of the test print is reproduced. In other words, even if deviations occur during printing and the need for re-alignment arises, this can be done easily without re-test printing.

Embodiment Next, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3. FIG.

In this embodiment, reference numeral 1 denotes a printing stage of a screen printing machine. Although details are not shown, stage 1
The printing press is provided with position adjusting means using a known mechanism, which can be moved and adjusted in the X-axis direction and the Y-axis direction on a plane, and is rotatable by a predetermined angle θ around the center portion as a center of rotation. Is provided. However, in this example, the adjustment is performed by the micrometer heads Mx, My, Mθ attached to the side of the stage 1 via a predetermined adapter or the like. In addition, in order to measure and display the adjustment amount, at the corner (the lower left in FIG. 2) of the side of the stage 1,
Dial gauges Gx, Gy, Gθ corresponding to each adjustment are provided.

A central portion of the upper surface of the stage 1 is a receiving portion 2 for the work W, and pins 3 corresponding to positioning holes provided in the work W are provided upright at appropriate places on the upper surface of the stage 1 to guide the work. The W is configured to be placed at a predetermined position on the stage 1.

On the other hand, a pedestal 4 for attaching a polyester film is provided around the outer periphery of the stage 1 via a space portion S for adjusting the movement of the stage 1 and fixed support means (not shown). A pair of (two) pin hole bushes 5, 5 for positioning a polyester film mounting frame, which will be described later, are fitted to the inner peripheral edge portion. However, one of them (the right side in FIG. 1) is an elongated hole to facilitate its attachment and detachment.

Next, the transparent sheet for test printing (polyester film) F, which can be called the main part of the present invention, will be described.

In this example, the polyester film F is attached to the upper surface of the polyester film mounting frame 6 formed in a rectangular frame shape by bonding the edges thereof, and is stretched while maintaining a certain tension state. I have. And stage 1
In a state where the workpiece W is placed at a predetermined position, the positioning pin 7 provided in the polyester film mounting frame 6 is fitted to the pin hole bush 5 of the pedestal 4.
Are fitted together, and are fixed to the pedestal 4 by an appropriate fixing means such as a screw (not shown). In this example, when the work W is placed, a small gap is maintained between the upper surface of the work W and the lower surface of the polyester film F. However, even if there is no gap, as long as the relative movement of the work W can be freely adjusted, the work W and the polyester film F may be in contact with each other.

On the polyester film F, an appropriate space is interposed, and a mask 9 integrally extended on the lower surface of the mask frame 8 is attached to a screen printing machine via supporting means (not shown). .

A plurality of small holes 10 are provided in the receiving portion 2 on which the workpiece W is placed, and a vacuum pump (not shown) is provided by a tube C or the like via a space inside the stage 1 below the receiving portion 2. It is connected.

Thus, the predetermined work W is placed at a predetermined position via the pins 3 of the stage 1, and the work W is sucked and fixed by the vacuum pump, and then the polyester film F is placed on the printing surface of the work W. A test print T of the print pattern of the mask 9 is performed by mounting the mask.

Thereafter, the stage 1 is appropriately moved and adjusted by the above-described adjusting means. However, the operator does not move the test print T so that the position to be printed on the work matches the position of the test print T. The stage 1 may be brought to a desired position while watching T and following the movement of the work W with the eyes. Therefore, in this example, it is clear that the work can be performed simply and in a short time by performing the trial printing.

After the alignment is completed, the stage 1 is locked at that position by operating a lock means such as a cam, for example, and the polyester film F is removed. It will be printed.

In this example, the polyester film (transparent sheet for trial printing) is attached to the polyester film mounting frame 6 along its edge, and is positioned with respect to the pedestal 4 by pinning. Since it is interposed on the upper surface, for example, even if the position is misaligned due to some reason during printing, the position can be easily adjusted by resetting a predetermined polyester film.

Furthermore, the work does not consist of one sheet,
In the case where several sheets are pressure-bonded, the printing position of the uppermost sheet, which is the printing surface, varies slightly for each work. In this case, conventionally, the work 1
A polyester film was stuck on each sheet, and a series of operations such as test printing, alignment, print wiping, and reprinting had to be repeated, but the polyester film was pinned as in this example. If the system can be positioned by a stop, the polyester film can be reset for each work in the same manner as described above, and printing can be sequentially performed only by following the above-described alignment procedure while observing the test print. Can be easily secured, which is extremely convenient.

In this example, as a transparent sheet for trial printing,
Although the case where a polyester film is used has been exemplified, a transparent sheet which does not generate wrinkles or looseness in a normal state and has a property of maintaining a certain tension state by itself may be used. is not. For example, a plate-shaped plate may be used as long as it is capable of trial printing. However, it is desirable to use a thinner one as much as possible in terms of positioning accuracy.

It goes without saying that an appropriate work can be selected and used.

(Effects of the Invention) Since the present invention is configured as described above, it has the following effects.

That is, in the alignment method according to the present invention, when adjusting the position of the work, the print position on the work is adjusted to an appropriate position while watching the test print of the test-printing transparent sheet and visually following the movement of the work. The position of the stage may be moved and adjusted so as to move. Therefore, in this alignment method, by performing trial printing once,
The operation can be performed easily and in a short time without requiring any skill, so that productivity can be improved and printing cost can be reduced.

In addition, there is no need to attach a transparent sheet for test printing such as a polyester film to the work when aligning, and the test printing is performed only once, so that the consumption of ink etc. can be greatly reduced and the test printing can be performed as before. Since there is no need to perform the erasing operation many times, the cost can be further reduced.

Furthermore, according to the present invention, since the transparent sheet for trial printing is mounted on the mounting frame and pinned to intervene on the print surface of the work, the work may be again positioned with respect to the mask. Even so, resetting the removed mounting frame with the transparent sheet, that is, pinning again, is very convenient because the position of the test print can be easily reproduced without the need for the test print again.

As is clear from the description of the above embodiment, in the present invention, the existing screen printing machine can be implemented by slightly modifying the existing screen printing machine, for example, by providing a pedestal or the like. There are significant effects.

[Brief description of the drawings]

FIGS. 1 to 3 are schematic structural views embodying the present invention in a screen printing machine. FIG. 1 is a cross-sectional view of a main part showing a state of alignment, and FIG. FIG. 3 is an enlarged view of a portion A in FIG. FIG. 4 is a schematic plan view for explaining a conventional alignment method. 1 ... Stage 9 ... Mask W ... Work F ... Polyester film (Transparent sheet for test printing) T ... Test printing

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-200698 (JP, A) JP-A-54-1117 (JP, A) JP-A-62-85944 (JP, A) 46628 (JP, U) Real opening 58-114068 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41F 15/08 303 B41F 15/26 H05K 3/12 610 H05K 3 / 34 505

Claims (1)

(57) [Claims] 1. A method for aligning a work placed on a stage with a printing mask of a screen printing machine by adjusting the position of the stage, comprising: a transparent sheet for trial printing; Is mounted on a mounting frame provided with positioning pins, and the mounting frame to which the transparent sheet for test printing is mounted is pinned on the outside of the stage with the positioning pins, whereby the test printing is performed. A transparent sheet is interposed on the printing surface of the work in a state where the work is relatively movable, under which the test printing is performed on the test-printing transparent sheet, and then the test printing is performed. The work is visually observed through a transparent sheet, and the position of the stage is adjusted so that the position of printing on the work matches the position of the test print. A method for aligning a work with respect to a mask in a screen printing machine.