JP2552354Y2 - Assembly board - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention has a plurality of single substrates for mounting chip components, and a boundary between these single substrates is defined by a separation hole and a substrate connecting portion like a so-called perforation. Are alternately arranged.

[0002]

2. Description of the Related Art A board on which chip components are mounted is generally surrounded by boundaries formed by alternately arranging separation holes and board connection portions like perforations in order to improve the mounting efficiency. The aggregate substrate has a plurality of single substrates. Therefore, after mounting various chip components, the above-mentioned board connecting portions are cut off to separate each single board.

This will be described with reference to FIG. The collective substrate 50 has a separation hole 54 formed of a long hole and a substrate connecting portion 6.
0 and two single substrates 5 which are alternately arranged and serve as boundaries between them.
2A and 52B are prepared. FIG. 7 is an enlarged view of a portion A in the vicinity of the board connecting portion 60. In order to separate each single board after mounting each chip component, the board connecting portion 60 must be cut with a nipper or the like.
FIG. 8 shows a state of cutting by the nipper 62.
FIG. FIG. 8 is shown by arrows BB in FIG.
FIG. 8 is a sectional view taken along line CC of FIG. 7.

[0004]

However, when each substrate connecting portion 60 is cut by the nipper 62, stress acts on the peripheral region due to the thickness of the nipper blade.
As a result, cracks 58A occur in the chip components 58 mounted in the vicinity of the board connection portion 60, and cracks occur in the solder used for mounting the chip components. Therefore, it is not possible to arrange chip components near the substrate connection part, which has been a great restriction in designing the substrate. Referring to FIG. 6, this means that the hatched areas 53 cannot be used effectively.

[0005] This is not to prevent the cracks generated at the time of cutting, but to prevent the substrate from being deformed or damaged in the process of mounting chip components on the substrate or performing a solder reflow process, the substrate is provided with an auxiliary. In some cases, a divided substrate portion is provided, and this is disclosed in Japanese Patent Publication No. 1-49031. In this publication, a disposal hole 10 is formed in order to prevent a crack from being generated in the perforated portion when the auxiliary divided substrate portion is punched and formed into a perforated shape. This discarded hole looks at first glance as the stress relieving hole of the present invention described below.

However, the discard hole of this publication is simultaneously punched and formed when the auxiliary divided substrate portion is punched and formed in a perforated shape, and the punch of the die used for the punching enters the discard hole. This is to prevent the perforated portion from being broken by the action of holding and fixing the auxiliary divided substrate portion, and is not a hole for reducing stress at the time of cutting the perforated portion as in the present invention. Also, the discarded hole in the publication is different from the case of the present invention in that the discarded hole is directed to the auxiliary divided substrate portion surrounded by the slits 8 and 8 ′. Discard hole 1
0 cannot be formed near the hole 9 at the perforation, but the hole of the present invention can be formed only in the vicinity of the substrate connecting portion so that the stress at the time of cutting can be reduced for the first time. The difference in place.

Accordingly, an object of the present invention is to provide a collective substrate having a structure in which even when a substrate connecting portion is cut, no stress is applied to the surrounding substrate portion and chip components.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned object, the present invention has a plurality of single substrates for mounting chip components, and separates the boundaries of these single substrates with a separation hole and a substrate connecting portion. Are provided alternately, wherein holes are provided in the vicinity of the substrate connecting portion to alleviate the stress generated when the substrate connecting portion is cut. .

[0009]

When the substrate connecting portion is cut by the nipper, stress is generated around the cutting edge due to the thickness of the blade of the nipper, but the stress is absorbed and reduced by providing a hole near the substrate connecting portion.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 shows a collective substrate 10 for mounting chip components according to the present invention. The aggregate substrate 10 has a long hole 14 for separating each single substrate.
And three single substrates 12A, 12B, and 12C surrounded by the substrate connecting portion 20 disposed therebetween. A round hole 16 or 16I is provided in the vicinity of each board connection part 20 of each of these single boards. The round holes 16 are formed at positions outside the boundaries of each single substrate, and the round holes 16I
Indicates the one formed at the inner position. These round holes may be in the vicinity of the board connecting portion 20, and the inside and outside thereof are not particularly limited. It may be outside or inside due to the space of the single substrate arrangement.

FIG. 2 is an enlarged view of the vicinity of one substrate connecting portion 20 of the single substrate 12A. The round hole 16 is provided outside the single substrate 12A. As another modification, a long hole 16L is provided outside the single substrate 12A, and as another modification, a round hole 16I is provided inside the single substrate 12A.

Next, the effects of the present invention will be described with reference to FIGS. FIG. 3 shows a conventional collective substrate having a width of 1 mm and a distance between each other of 2.5 mm as shown in FIG. . The strain due to the stress when the substrate connecting portion 20 was cut by the nipper was measured at a measurement point MP1 separated from the substrate connecting portion 20 by 2 mm.

FIG. 4 shows a collective substrate according to the present invention in which a round hole 16 having a diameter of 2 mm is formed at a position shown in FIG. . The distortion caused by the stress when the substrate connecting portion 20 was cut by the nipper was measured at a measurement point MP2 which was the same position as in FIG. 3 and was 2 mm away from the substrate connecting portion 20.

In each of the above-described strain measurements, the substrate connecting portion 20
Using two types of thickness of the nipper used for cutting, the strain for the cutting stress by each nipper is measured. As shown in FIG. 5, the two types of nippers have the same cutting edge angle θ, but have different thickness dimensions, one being 0.9 mm and the other being 0.5 mm.

The measurement data D1 and D2 shown in FIG. 5 are both of the conventional collective substrate shown in FIG. 3 which is to be cut, cut by a nipper having a thickness of 0.9 mm, and a nipper having a thickness of 0.5 mm. Measuring point MP1 for cutting by
Is the compression strain. Further, the measurement data D3 and D4 indicate that the object to be cut is the collective substrate of the present invention shown in FIG. Measurement point M
This is the compression strain of P2. Also, circles M1, M2, M3, M4
Indicates the average value of each data.

As a result of these measurements, the average data M1 and M
Comparison with No. 2 shows that the thinner the nipper, the smaller the distortion. The same can be said of comparing the other average value data M3 and M4. Furthermore, comparing the average value data M1 and M3 or the average value data M2 and M4,
It can be seen that the compressive strain generated by the collective substrate according to the present invention is reduced as compared with the conventional collective substrate. In this experiment, the distortion was reduced by about 40%.

As shown in FIG. 4, it is desirable to provide a hole 16 for reducing stress and strain caused by cutting in the vicinity of the substrate connecting portion 20. However, if this hole is too close, it becomes difficult to manufacture a collective substrate. The dimensions L shown in the figure
Is desirably designed to be equal to or greater than the thickness of the substrate.

[0018]

As is apparent from the above description, according to the present invention, the distortion generated when the substrate connecting portion is cut by the nipper can be reduced by the holes provided near the substrate connecting portion. Accordingly, the vicinity of the board connection portion is not damaged, chip components can be arranged there, a design using the board can be effectively used, and high-density mounting is also possible. Further, even when the thickness of the nipper is increased, the stress at the time of cutting the substrate connecting portion is reduced, so that the durability of the nipper can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a collective substrate according to the present invention.

FIG. 2 is an enlarged view of the vicinity of a board connecting portion of the collective board according to the present invention.

FIG. 3 is an enlarged view of the vicinity of a board connecting portion of a conventional collective board, and is a view showing an object of the experiment of FIG. 5;

FIG. 4 is an enlarged view of the vicinity of a board connecting portion of the collective board according to the present invention, and is a view showing an object of the experiment of FIG. 5;

FIG. 5 is a graph for explaining an effect of the collective substrate according to the present invention.

FIG. 6 is a plan view of a conventional collective substrate.

FIG. 7 is an enlarged view of a portion A in FIG. 6;

FIG. 8 is a cross-sectional view taken along line BB of FIG. 7 when the substrate connecting portion of FIG. 7 is cut by a nipper.

9 is a cross-sectional view taken along line CC of FIG. 7 at the time of cutting the board connecting portion of FIG. 7 with a nipper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Collective board 12A, 12B, 12C Single board 14 Separation hole 16, 16I Stress relaxation hole 18 Chip component 20 Board connection part

Claims (1)

(57) [Scope of request for utility model registration] 1. A collective board comprising a plurality of single boards for mounting chip components, and a boundary between these single boards is formed by alternately arranging separation holes and board connecting portions. And a hole provided in the vicinity of the substrate connection portion for relaxing stress generated when the substrate connection portion is cut.