JPH0645739A - Manufacturing method of printed substrate - Google Patents

Abstract

PURPOSE:To enable a clip to be firmly soldered onto a substrate even if the flat plate part of the clip, etc., of an F type connector is not e.g. protruded from a hole in the substrate. CONSTITUTION:Two each of round holes 3 are formed on a substrate part by NC drilling step and then metallic films 4 are formed on respective inner peripheral surfaces of both round holes so as to turn them into through holes 3 while the substrate part between both round holes 3 is cut off in narrower width than the inner diameter of the round holes 3 so as to form a square hole 6. Through these procedures, when a clip 27 of an F type connector 26 is inserted into the square hole 6 to be soldered, the clip 27 can be firmly soldered due to the through holes 3 formed by the metallic films 4 formed on the inner peripheral surface of the round hole 3 at both ends of the square hole 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board manufacturing method.

[0002]

10 and 11 relate to printed circuit boards 20 and 21 manufactured in a general manufacturing process. In this case, the printed circuit board 20 shown partially broken in FIG. 10 is a double-sided type. The printed circuit board 20 is formed with a number of round holes 24 corresponding to the number of the lead terminals 23 of the electronic component 22. The round holes 24 are formed on the inner peripheral surface of the lead holes by soldering the lead terminals. In order to improve reliability, a required metal film 25 is formed by a plating process or the like to form a through hole. The printed circuit board 21 partially shown in FIG. 11 has a flat type bending clip 27 of the F type connector 26. Although the square hole 28 into which the tip is inserted is formed, the inner peripheral surface of the square hole 28 does not have a metal film formed on the inner peripheral surface thereof unlike FIG. It has not been.

As described above, in the printed circuit board 20 of FIG. 10, the metal film 25 is formed on the inner peripheral surface of the round hole 24 to form a through hole, whereas in the printed circuit board 21 of FIG. The metal film is not formed on the peripheral surface and it is not made into a through hole. In the general manufacturing process of a printed circuit board, a large mother board for a printed circuit board is provided with a large number of circular holes for mounting electronic parts with an NC drill. After forming,
A metal film is formed on the inner peripheral surface of a large number of round holes by plating to form through holes all at once, but square holes are not formed as through holes because they are formed in a subsequent press working step.

Of course, it is also possible to form a square hole by pressing before forming a through hole into a round hole and form the through hole at the same time as the round hole. However, unlike the round hole, the inner circumference of the square hole is different. Even if a metal film is formed on the surface by plating to form a through hole, the reliability of the formation state of the through hole is extremely poor. Moreover, since the step of forming a square hole by press working is increased by one step, it is generally such a case. It is difficult to adopt a large square hole as a through hole from a cost standpoint.

[0005]

By the way, in the case where the lead terminal such as the clip 27 of the F-type connector 26 is flat, the printed board 21 as shown in FIG. The F-type connector 26 is roughly divided into a case 29 and a holder, as shown in FIG. 12 as an example of its structure. 30 and the clip 27, there is a tolerance in manufacturing and assembling each component in such a connector 26. Then, the connector 26 is connected to the chassis 3 of an appropriate electronic device as shown in FIG.
When the tip end portion of the bent clip 27 is inserted into the square hole 28 of the printed circuit board 21 which is mounted on the chassis 31 by means not shown in the figure, the tip portion of the clip is the square hole 28. When projecting above the printed circuit board 21 from 28, even if the inner peripheral surface of the square hole 28 is not formed as a through hole, the tip end portion of the clip is firmly soldered with the thick solder layer 32 on the upper surface of the printed circuit board 21. be able to.

However, depending on the degree of the above-mentioned tolerance, the tip end portion of the clip does not project upward from the square hole 28 as shown in FIG. 14, and when the tip end portion of the clip is soldered in that state, Solder layer 32
Has a problem in that the tip portion of the clip cannot be firmly connected to the printed board 21 and the mechanical reliability is lowered.

Such a defect is not limited to this connector 26, and for example, as shown in the assembly view of FIG. 15A, a printed circuit board 34 is provided in a frame 33 of the tuner, and the lower surface of the printed circuit board 34 is When a space between the bottom surface of the frame 33 and the bottom surface of the frame 33 is divided by a shield plate 35 into a plurality of partition chambers according to applications, a flat plate-shaped convex portion 36 provided on the shield plate 35 is provided in a square hole of a printed circuit board 34. When the protrusion 36 is inserted into the hole 37 and is soldered to the printed board 34, and the protrusion 36 has a length sufficient to project from the square hole 37 to above the upper surface of the printed board 34. As the shield plate 35, as shown in the development view of FIG. 15B, the convex portion 36 bites into a part of the shield plate 35. This is as a shield plate 35 is a portion of code, for example 35a, the convex portion 36 3
It is necessary to have a separate piece structure with the 5b part,
There is an inconvenience that extra cost is required in manufacturing or assembling the shield plate 35.

Therefore, in the present invention, the manufacturing method is such that the entire hole shape on the printed circuit board is a square hole, and the square hole can be formed into a through hole in the same step as forming a round hole into a through hole. Therefore, the tip clip such as an F-type connector has a flat plate shape, a flat plate-shaped convex portion of the shield plate, in short, electronic parts to be inserted into the square holes, and flat plate parts of other parts are through-holes. It is an object of the present invention to provide a method for manufacturing a printed circuit board, which solves the above-mentioned problems by inserting it into a square hole that is made into a solid shape and making a strong connection by soldering.

[0009]

In order to achieve such an object, in a method of manufacturing a printed circuit board according to the present invention, at least two round holes are formed at a predetermined distance in a board portion as described in claim 1. Forming a round hole, a through hole forming step of forming a metal film on the inner peripheral surface of each round hole to form a through hole between the two round holes, and It is characterized in that it has a deletion step of deleting the width narrower than the inner diameter, and that each of these steps is performed in the order described above.

The round hole forming step as described in claim 2
A round hole may be formed by drilling,
As in claim 3, the removing step may be performed by pressing the substrate portion.

[0011]

According to the above manufacturing method, at least two round holes are formed in the substrate portion at a predetermined distance, and then a metal film is formed on the inner peripheral surface of each round hole to form the through holes. Then, the board part between both round holes is deleted so that it is narrower than the inner diameter of the round hole.Therefore, a hole with a shape close to a square hole is formed on the board part as well as its corners. The inner peripheral surface of the round hole on both sides of the hole is to be a through hole.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

A method of manufacturing a printed circuit board according to the present invention will be described with reference to FIGS. First, as shown in FIG. 1, a mother board 1 to be a printed circuit board is prepared, and the mother board 1 is separated from the mother board 1 by a predetermined distance, for example, a distance corresponding to the distance in the longitudinal direction of the clip at the tip of the F-type connector. (Dashed line circle part) 2 and 2 are set. Then, for each of the substrate parts 2 and 2 set as shown in FIG.
After forming the round holes 3 and 3 by C drilling, the inner peripheral surface of each of the round holes 3 and 3 is plated to form the metal films 4 and 4 as shown in FIG. Make both round holes through holes. At this time, a metal film may be formed on the substrate surface around the round holes 3 and 3.

After this through-hole forming step, although not shown in the figure, a predetermined wiring pattern, electrode lands and the like are formed on the mother substrate 1 by a known method, and a resist film is printed on the mother substrate surface.

Next, the mother substrate 1 is cut by press working according to the size of the printed circuit board. With the square punch used in this press working, as shown in FIG.
As shown in FIG. 5, which is a cross-sectional view taken along the line AA of FIG. 4, the width of the substrate portion 5 between the round holes 3 and 3 is smaller than the inner diameter of the round holes 3 and 3. The F-shaped connector is punched with a width matching the thickness of the clip at the tip to form the square hole 6, and the square hole 6 connects the both round holes 3, 3.
As a result, a required printed circuit board 8 having a square hole-shaped portion 7 (comprising both round holes 3, 3 and square hole 6) having both ends formed as through holes is manufactured. Although the number of round holes is two in the embodiment, the number of round holes is not limited to two. For example, three round holes 3 are formed as shown in FIG. In the embodiment, the two round holes are on a straight line, but not on a straight line, for example, as shown in FIG. Similarly, it may be an L-shape in which two round holes 3 ″ and 3 ″ are formed in the lower direction in the figure, and the substrate portion between the round holes is deleted in a square hole shape as described above. .

As described above, according to the present invention, the printed circuit board 8 manufactured as shown in FIGS. 4 and 5, for example, has the square hole-shaped portions 7 having through holes at both ends thereof. For example, a lead terminal 9 of an electronic component having a flat plate configuration as shown in FIG. 8 and a side view of FIG. 9 can be inserted into the hole-shaped portion 7, and when the lead terminal 9 is inserted, the lead terminal 9 can be inserted. Even if the terminal 9 does not protrude from the square hole portion 7 or even if it protrudes, it slightly protrudes, even if the thickness of the solder layer for soldering the lead terminal 9 on the upper surface of the printed circuit board 8 becomes thin. The lead terminals 9 are firmly soldered with the solder 10 in the through-hole portions on both sides of the square hole portion 7.

[0017]

As described above, according to the present invention, at least two round holes are formed in the substrate portions separated by a predetermined distance, and then a metal film is formed on the inner peripheral surface of each round hole. Since the round hole is made into a through hole, and then the board part between both round holes is deleted so as to be narrower than the inner diameter of the round hole, a square hole shape part is formed between both round holes as a whole hole shape. , Since the inner peripheral surfaces on both sides of the square hole-shaped portion will be through holes, it is possible to insert, for example, a lead terminal of an electronic component having a flat plate-shaped configuration into the square hole-shaped portion, In the case of the insertion, the lead terminal does not protrude from the square hole shaped portion, or even if it protrudes, it is a slight protrusion, so even if the thickness of the solder to which the lead terminal is soldered becomes thin on the upper surface of the printed circuit board, The lead terminal is a square hole It will be firmly soldered on both sides of the through hole moiety.

[Brief description of drawings]

FIG. 1 is a plan view of a mother substrate in a manufacturing method according to an embodiment of the present invention.

FIG. 2 is a plan view for explaining a step of forming a round hole in the manufacturing method according to the embodiment of the present invention.

FIG. 3 is a plan view for explaining a step of forming a round hole into a through hole in a manufacturing method according to an embodiment of the present invention.

FIG. 4 is a plan view of a substrate portion for explaining a step of removing a substrate portion between round holes in a manufacturing method according to an embodiment of the present invention.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a plan view corresponding to the step of FIG. 4 in a manufacturing method according to another embodiment of the present invention.

FIG. 7 is a plan view corresponding to the step of FIG. 4 in a manufacturing method according to still another embodiment of the present invention.

FIG. 8 is a sectional view from the front for explaining the soldering of the lead terminal to the printed board according to the embodiment of the present invention.

9 is a cross-sectional view as seen from the side surface of FIG.

FIG. 10 is a partial perspective view of a main part of a printed circuit board manufactured by a manufacturing method of a conventional example and having a round hole.

FIG. 11 is a partial perspective view of a main part of a printed circuit board manufactured by a manufacturing method of a conventional example and having a square hole.

12 is a half cross-sectional view of the F-type connector attached to the square hole of the printed circuit board of FIG.

13 is a cross-sectional view of the case where the clip of the F-type connector of FIG. 11 is attached to a printed circuit board having a square hole and the amount of protrusion of the clip from the square hole is sufficient when viewed from the side.

FIG. 14 is a cross-sectional view seen from the side when the clip of the F-type connector of FIG. 11 is attached to a printed circuit board having a square hole and the amount of protrusion of the clip from the square hole is small.

FIG. 15 is a perspective view of the tuner when the convex portion provided on the shield case of the tuner is inserted into the square hole of the printed circuit board.

[Explanation of symbols]

 1 Mother board 2 Board part 3 Round hole 4 Metal film 5 Board part between round holes 6 Square hole 7 Square hole shaped part 8 Printed board

Claims (3)

[Claims] 1. A round hole forming step of forming at least two round holes (3, 3) at a predetermined distance from each other on a substrate portion (2, 2), and inner peripheral surfaces of both round holes (3, 3). On the metal film (4, 4)
Through hole forming step (3) to form both through holes (3, 3) into holes.
And a removing step of making the width narrower than the inner diameter of the printed circuit board, and performing each of these steps in the order described above. 2. The method of manufacturing a printed circuit board according to claim 1, wherein the round hole forming step forms the round holes (3, 3) by drilling. 3. The method of manufacturing a printed circuit board according to claim 1, wherein the removing step is to remove the substrate portion (5) by pressing.