JPH0320834Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to printed circuit boards on both sides, especially printed circuit boards with through holes penetrating both sides. This invention relates to a cross gauge for positioning an original pattern (circuit pattern) to be closely printed on both surfaces of a substrate when manufacturing a substrate that requires alignment of relative positions.

[Conventional technology]

As is well known, the material of a printed circuit board is a laminate of a synthetic resin laminate and a copper foil approximately 35 μm thick.The original board pattern corresponding to the circuit pattern in which electronic components will be formed on the surface of the printed circuit board is printed on a film original board. The original pattern is printed and developed on the surface of the substrate coated with photoresist, and then etched to finish the pattern. The through-holes in the through-hole print substrate are a large number of small holes that are drilled on both sides of the board, in other words, to connect the circuit patterns made on the front and back sides, and the inner walls are plated to make them conductive. It is something that has been set.

By the way, printed circuit boards are required to have increasingly high-density circuit configurations, and the dimensional accuracy of circuit patterns is required to be high. In light of the analysis of the causes of circuit board failures, it has become clear that the positioning accuracy for mounting the upper and lower film originals on the upper and lower frames, respectively, has become an extremely important factor. For example, as a function of a printed circuit board, contact with a connector, etc.
For conductive connections between layers, solder connection terminals (lands) for parts, etc., when the land 1 has a through hole as shown in Figure 1A, if the positions of the land 1 on the front and back are misaligned, The width 2 of the land 1 may become non-uniform as shown in FIG. 4B, or a portion of the land 1 around the through-hole may be chipped, causing problems in soldering in the subsequent process.

However, the conventional method for positioning the original pattern on a double-sided printed circuit board is to attach the original film for the upper frame to the lower surface of the upper frame, and then visually align the original film for the lower frame on the upper surface of the lower frame. Accuracy is still poor, alignment takes time, and the above-mentioned positional deviation between the front and back lands occurs.

Therefore, the inventor of the present invention attempted to use the cross gauge for positioning the original plate in the original carriage in the plate printing machine used in photoengraving work as it is for positioning the printed circuit board. In other words, the conventional cross gauge is for one side, as shown in FIG. required. In the case of a cross gauge that has a slight error in the perpendicularity, that is, if there is an error in the perpendicularity of the angle α, as shown in Fig.
This results in a difference of 2α. To be more specific, the method of using this cross gauge is as shown in Figure 2 C.
A lower frame glass plate 6 is mounted and fixed on the lower frame 5, and holes 7, 7 are bored at both ends thereof. The original film is placed on the glass plate 6, and the cross gauge is mounted on the original film 8 at a fixed position where the protrusions 9, 9 on both frames of the cross gauge are engaged with the holes 7, 7 of the lower frame 5. , original film 8 on lower frame glass plate 6
The position of the original film 8 with respect to the lower frame glass plate 6 is determined by aligning the register marks (registration marks) of the original film 8 with the vertical and horizontal cross gauge standard perforations 4. Paste it on the bottom frame 5. A similar operation is performed on the upper frame (not shown) and it is attached to the original film (not shown). In this way, when the upper and lower frames are aligned and a printed circuit board is interposed between them, if there is an error of α in the perpendicularity, an error of 2α will occur between the upper and lower original films.

Therefore, if the cross gauge is processed with ultra-precision,
Although the above-mentioned problems can be avoided, the cross gauge becomes expensive and is sometimes used on one side, resulting in inefficiency.

[The problem that the idea aims to solve]

When pasting the original film for the upper frame on the lower surface of the conventional upper frame, and then aligning and pasting the original film for the lower frame on the upper surface of the lower frame by visual inspection, the original film for the lower frame
It took too much time to align them accurately so they wouldn't shift.

In addition, when using a cross gauge for single-sided alignment, if there is an error in perpendicularity to the reference line of the cross gauge, there is a problem that the error will be double that for both the upper and lower patterns. It would be expensive to manufacture an ultra-precision single-sided cross gauge.

[Means to solve the problem]

The structure of the present invention is that a pair of alignment pins are provided protruding from both sides of the frame of a cross gauge made of a transparent plate to engage with the upper frame and the lower frame, respectively, for attaching the original plate pattern, and a register of the original plate pattern for the upper frame. This is a double-sided pattern matching cross gauge in which a gauge reference line for matching the mark and the register mark of the original plate pattern for the lower frame is provided at the same relative position on both sides of the transparent plate.

[Effect]

A gauge reference line is inserted into the transparent plate of a cross gauge, and the reference line overlaps the front and back when viewed from one side, that is, it is attached at the same relative position on the front and back. Even when there is no absolute precision in the perpendicularity of the lines, there is no error in the relative precision of the front and back sides for aligning each original film with reference lines on both sides of the cross gauge.

Therefore, the cross gauge and the upper frame are engaged with the upper frame alignment pin of the cross gauge, and the gauge reference line of the cross gauge is aligned with the register mark of the original pattern for the upper frame, and the original film for the upper frame is aligned. Attach it to the top frame.

Next, the lower frame is similarly engaged with the cross gauge using the alignment pin for the lower frame of the cross gauge, and the original plate pattern for the lower frame is attached to the lower frame, so each original plate pattern can be easily attached to the upper and lower frames. They can be attached at relatively the same positions, and there is no relative positional shift between the two original patterns.

〔Example〕

The configuration of the present invention will be explained in detail based on examples.

Figure 3 shows a cross gauge 10 which is an embodiment of the present invention.
Then, on the upper and lower surfaces of the cross gauge glass plate 3 fixed to the cross gauge 10, a cross gauge reference line 4 that can be visually recognized at the same position when viewed directly from one side is carved,
On both sides of the cross gauge frame 10', lower frame alignment pins 11 and upper frame alignment pins 12 are protruded from both upper and lower surfaces, respectively.

Further, in this cross gauge 10, as shown in FIG. 4, a positioning bush 13 is embedded in the cross gauge glass plate 3.

As shown in FIG. 4, such a cross gauge 10 is placed on the lower frame glass plate 6 fixed to the lower frame 5 by inserting the lower frame alignment pins 11 into the holes 7. However, a lower frame bushing 14 is also embedded in this lower frame glass plate 6, and the lower frame bushing 14 has a slightly larger hole 15 drilled therein.
A board positioning pin 16 is loosely fitted to the board positioning pin 16 . A flange 17 is fixed to the base of the board positioning pin 16, and screws 18, 18 are provided on the flange 17.

Therefore, the cross gauge 10 is placed on the lower frame glass plate 6, and the board positioning pin 16 is passed through the lower frame bushing 14 from the bottom side of the lower frame glass plate 6, and its tip is inserted into the cross. Insert into positioning bush 13 of gauge 10. And screw 18,1
At step 8, the board positioning pin 16 is fixed to the lower frame bushing 14. This allows the board positioning pin 1
6 is set as the lower frame glass plate 6. in this case,
A pin alignment jig 30 as shown in FIG. 7 may also be used. That is, for example, the alignment pin 32 for the lower frame is attached to the metal plate 31 by the alignment pin 1 of the cross gauge 10.
Two pin positioning holes 33 are provided at a certain distance inward from the lower frame alignment pins 32, respectively. The board positioning pin 16 is positioned by the pin positioning hole 33, and the pin 16 is fixed.

After setting the board positioning pins 16 on the lower frame glass plate 6, as shown in FIG. Place the film 8 on the glass plate 6 for the lower frame.
Place the cross gauge 10 on the upper surface and insert the lower frame alignment pin 11 of the cross gauge 10 into the hole 7 of the lower frame 5.
Place it so that it fits.

Here, by illumination from the light table 34, the register mark on the original film 8 is aligned with the reference line 4 for the lower frame of the cross gauge 10, and the original film 8 is temporarily fixed to the lower frame glass plate 6 with tape or the like.

Next, the upper frame 19 is placed on the light table 34, the original film 8' for the upper frame is placed on the glass plate 6', and the cross gauge 1 is turned over from above.
0 is placed in the holes 20, 20 on both sides of the upper frame 19 while fitting the upper frame alignment pins 12 of the cross gauge 10. Reference line 4 for the upper frame of the cross gauge 10
The register marks of the original film 8' are aligned with the original film 8', and the original film 8' is mounted on the upper frame 19.

In this way, the original films 8 and 8' are attached to the upper and lower frames 5 and 19, respectively, and the printed circuit board 2
1, form a relatively accurate positional relationship.

Next, the upper and lower frames 5 and 19 are attached to the exposure apparatus (only the main parts are shown) as shown in FIG. Insert the holes 7, 7 of the lower frame 5 into the holes 7, 7 of the lower frame 5. At this time, since the two board positioning pins 16, 16 are provided upright on the lower frame 5, the printed circuit board 2 is placed on the original film 8 attached to the lower frame 5.
1, the printed circuit board 21 is skewered by the board positioning pins 16, 16. Then, the upper frame 19 with the original film 8' pasted thereon is inserted through the upper and lower frame guide pins 22, 22, and placed on the printed circuit board 21.
and place it on the mounting frame. The protruding board positioning pins 16, 16 are inserted into slightly larger holes 23, 23 provided in the upper frame 19. here,
In practical work, it is desirable to fix the upper and lower original films 8, 8' to the upper and lower glass plates 6, 6' by vacuum suction means or the like, if necessary.

The device frame has two upper and lower stages 24 and 25, and four bearings are connected to both ends of the lower stage 25 via bearings 26 and 26.
Threaded bars 27 (see FIG. 6) for vertically driving the upper frame of the book are fitted, and the upper stage 24 is threadedly engaged with these bars 27. Bevel gear 2 at the tip of these bars 27
8, by rotating these bars 27, the upper and lower frames 5 and 19 are brought close to each other, and the printed circuit board 21 is pressed to such an extent that warpage is eliminated.

After being attached to the exposure apparatus in this way, the sixth
As shown in the figure, exposure is performed using parallel light beams from upper and lower light sources 29, 29.

Incidentally, instead of the upper and lower frame guide pins shown in FIG. 5, guide uneven portions 35 and 35' as shown in FIG. 9 may be attached to the holes 7 and 20 of the upper and lower frames 5 and 19, respectively.

Further, in FIG. 3, the upper frame alignment pin 12 and the lower frame alignment pin 11 of the cross gauge 10 may be removed and alignment holes 36, 36 may be provided as shown in FIG. 10. In this case, when positioning the original film on the lower frame 5 or the upper frame 19, cylindrical or tapered alignment pins may be inserted into the respective alignment holes 36, 36.

〔effect〕

According to the present invention, the upper frame and the lower frame are respectively engaged with the matching pins of the cross gauge for double-sided pattern matching, and the original plate pattern for the upper frame and the original plate pattern for the lower frame are placed at the same relative position on both sides of the cross gauge. Since positioning is performed using the front and back reference lines attached to the board, the relative positioning of the upper and lower frame master patterns can be performed accurately without requiring a long time, regardless of the absolute accuracy of the reference lines, and the circuits on both sides of the board can be accurately positioned. Double-sided exposure can be performed without relative positional deviation of the pattern.

[Brief explanation of the drawing]

Figures 1A and 2B are plan views of essential parts of a land, which is one of the elements of a printed circuit board, Figure 2A is a perspective view of a conventional cross gauge, and Figure 2B represents the squareness of a conventional cross gauge. Figure 2C is a cross-sectional view of the conventional cross gauge and lower frame, and Figure 3 is a cross-sectional view of the conventional cross gauge and the lower frame.
4 is a detailed cross-sectional view of the main parts of the cross-shaped gauge in FIG. 3 and the lower frame; FIG. 5 is a cross-sectional view of the main parts of the exposure apparatus which is an example of the use of the present invention. , FIG. 6 is an exploded perspective view of FIG. 5, FIG. 7 is a perspective view of the pin alignment jig, FIG. 8 is a perspective view of the light table, and FIG. 9 shows the main points of another embodiment in FIG. FIG. 10 is a sectional view of a main part of another embodiment in FIG. 3. 3...Cross gauge glass plate, 4...Cross gauge reference line, 5...Upper frame, 10...Cross gauge, 1
0'... Frame for cross gauge, 11... Aligning pin for upper frame, 12... Aligning pin for lower frame, 21... Printed circuit board.

Claims (1)

[Scope of utility model registration request] A pair of alignment pins are protruding from both sides of the frame of the cross gauge made of a transparent plate to engage with the upper frame and lower frame, respectively, for attaching the original plate pattern, and register marks for the original plate pattern for the upper frame and for the lower frame. A cross gauge for double-sided pattern matching, in which gauge reference lines for matching register marks on the original plate pattern are attached at the same relative position on both sides of the transparent plate.