JP2003204127A - Printed board structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed board structure in which a printed board can be divided easily without requiring any extra expense nor damaging electronic parts mounted on the board near the end face of the product section of the substrate. <P>SOLUTION: In the printed board structure, V-grooves 11A and 11B are formed on the board dividing line of the printed board 10 which becomes the boundary between the product section 10A on which the electronic parts 13 are mounted and a disposable board section 10B which is removed afterward and a plurality of through holes 12 made through the board 10 along the grooves 11A and 11B. The holes 12 are arranged selectively with respect to the parts 13. <P>COPYRIGHT: (C)2003,JPO

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 structure applied to a printed circuit board which is divided into a product part on which electronic parts are mounted and a discarded board part to be removed.

[0002]

2. Description of the Related Art Generally, a printed circuit board using a glass epoxy base material is used for forming a wiring pattern in an electronic device. This printed circuit board considers production efficiency,
It is formed by punching out a plurality of printed circuit boards on a fixed-size substrate. Also, to match the size to the standard size substrate,
In some cases, a discarded substrate portion having no circuit pattern may be provided in the peripheral portion of the product portion on which the circuit pattern is formed and electronic components are mounted. A plurality of electronic components are mounted on a standard-size substrate provided with such a printed circuit board product section and a discarded board section, and after the electronic components are mounted, division of each printed circuit board into product sections and division of the discarded board section are performed. Removal will be performed. The division of the printed circuit board product section and the removal of the discarded board section are performed by fixing one of the V grooves along the V-shaped groove provided on the fixed-length board and then applying a stress to the other. The division is performed at the border.

[0003]

By the way, in the above prior art, the deformation (warpage) of the substrate is large near the V groove of the product portion of the printed circuit board, and when the electronic component is mounted, the electronic component If a component is distorted and applied with a strain equal to or higher than the withstanding capacity of the electronic component, the electronic component will be damaged. Therefore, in order to prevent this, usually, a method of deepening the V-groove or a printed circuit board is used. To prevent deformation, the substrate is fixed (pressed, between the target electronic component and the V groove).
A method of providing a substrate fixing and supporting mechanism is adopted.

However, in the method of deepening the V-groove described above, if the V-groove is made too deep, the warp of the substrate becomes large, and in the work process before the division, the component mounting failure due to the large warpage and the divided portion of the substrate are caused. There is a risk of breaking out.

In the method of providing the board fixing / supporting mechanism described above, there is a tendency that the board fixing / supporting mechanism cannot be set due to high-density mounting accompanying the high functionality of electronic products in recent years. In particular, for high-density mounting, when the target electronic component is close to the end surface of the product part of the printed circuit board, it is not possible to set a substrate fixing and supporting mechanism between the electronic component and the V-groove, which can increase the effect of preventing distortion. Therefore, when forming a wiring pattern with such a configuration, only the target electronic components are post-soldering by hand soldering, or the standard length substrate is divided for each product part of each printed circuit board before mounting all electronic components, Either one of soldering each component to the product part of the divided printed circuit board by flow must be adopted. Alternatively, as described in Japanese Patent Application Laid-Open No. 2001-15866, there is a method of providing a board fixing support pin insertion hole, but there is a problem that a setting space cannot be taken during high-density mounting.

The applicant of the present application has considered a method of providing slits (long holes) on or around the V groove, but when there are too many slits, the same problem as when the V groove is deepened is caused. Has been identified. In addition, even if boards with the same external shape have different slit positions depending on the component layout, it is necessary to use a large number of dies for the printed circuit board, or it becomes clear that the distortion to the parts is large after the printed circuit board is designed. When doing so, it has been found that there is a problem that a large amount of mold setting cost and mold changing cost will occur.

As described above, according to the above-mentioned conventional technology, it is possible to easily divide the board in the high-density mounting board without extra cost, especially without damaging the electronic parts arranged near the end surface of the board product part. There is a problem that you can not do.

The present invention has been made in view of the above-mentioned circumstances, and easily divides a board without extra cost and without damaging an electronic component mounted near the end surface of the board product. An object of the present invention is to provide a printed circuit board structure capable of achieving the above.

[0009]

The typical ones of the inventions disclosed in the present application will be briefly described as follows. That is, a groove is formed on the board dividing line at the boundary between the product part on which the electronic component is mounted and the discarded board part to be removed, and a plurality of front and back through holes or bottomed holes are formed on the groove and along the groove. It features a printed circuit board structure. As a result, when the board is divided, the board strength at the hole installation portion is significantly reduced, and the warpage of the board due to the division is reduced. As a result, the strain applied to the electronic component is reduced, and component damage can be prevented. Therefore, it is effective for an electronic component mounted near the end face of the product part and subjected to a large strain. The operation will be described in the section of the next embodiment.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a printed circuit board showing an embodiment of the printed circuit board structure of the present invention. 2 is a sectional view taken along the line II of FIG.

In FIGS. 1 and 2, reference numeral 10 is a printed circuit board, 10 A is a product section on which electronic parts are mounted,
10B is a discarded board portion on which electronic parts are not mounted, 11A,
11B are V on the dividing line of the printed circuit board 10.
Grooves (grooves), 12A to 12E (12 when collectively referred to) are front and back through holes, and 13 is an electronic component mounted near the board end surface of the product portion 10A.

More specifically, the printed circuit board 10 has a product portion 10A on which a circuit pattern is formed and electronic components are mounted, and a discarded substrate portion 10B on which no circuit pattern is mounted and electronic components are not mounted. Product Department 10
V-shaped grooves 11A and 11B having a V-shaped cross section are formed at the boundary between A and the discarded substrate portion 10B to divide them.

The V grooves 11A and 11B are formed, for example, in a linear shape. Further, the V-shaped groove 11A is arranged on the front surface of the printed circuit board 10 and the V-shaped groove 11B is arranged on the rear surface of the printed circuit board 10 such that the apexes of the respective V-shapes face each other. V groove 11
A plurality of front and back through holes 12A to 12E penetrating in the front and back direction of the printed circuit board 10 are formed in A and 11B.
The front and back through holes 12A to 12E are V grooves 11A and 11B.
Are arranged along. In addition, front and back through holes 12A to 12E
Are selectively formed for the electronic component 13 mounted near the V groove 11A. The front and back through holes 12A to 12
E is formed by a drill or the like.

Here, the hole diameter φD of the front and back through holes 12, the hole pitch P, the hole row width W (the number of holes N), and the hole center position (V).
The deviation from the groove center) is a condition such as the thickness of the printed circuit board 10, the number of layers, the depths of the V grooves 11A and 11B, the distance L from the substrate edge (V groove) to the electronic component 13, the type of the electronic component 13, and the like. Therefore, the optimum value is selected. As an example,
Thickness of printed circuit board 10: 1.6 mm, V groove 11A, 1
If each depth of 1B is 0.6 mm and the distance L from the substrate edge (V groove) to the edge of the electronic component (surface-mount chip ceramic capacitor) 13 is 15 mm or less, φD
= 1.2 mm, P = 1.2 mm, W = 13 ± 3 mm, hole center position: V-shaped vertex positions of the V grooves 11A and 11B are preferable. In addition, in the case where the outer shape of the product portion 10A should not be impaired and the hole diameter φD is larger than the width X of the V grooves 11A and 11B, the hole center should be (φD−X) / 2 from the V-shaped vertex. It may be shifted.

As described above, since the front and back through holes 12 are selectively provided on the V-grooves 11A and 11B with respect to the electronic component 13, when the substrate is divided (stress is applied in the arrow direction of FIG. It is possible to reduce the warpage of the substrate in the mounting portion of the electronic component 13 (divided and removed), reduce the strain on the electronic component 13, and prevent damage. Further, since it is not necessary to change the mold such as installing a slit and only a small number of holes need to be drilled, there is no extra cost and the division process can be easily performed.

In addition, it goes without saying that the present invention can be modified in various ways without departing from the spirit of the present invention. That is, the front and back through holes 12 may be arranged in a continuous state without a gap. The shape of the front and back through holes 12 may be other than the illustrated round shape. further,
The front and back through-holes 12 may be replaced with bottomed holes (thin bottom is thin) in which the mounting side of the electronic component 13 is opened.

[0017]

As described above, a printed circuit board structure capable of dividing a board easily without causing extra cost without damaging electronic components mounted near the end surface of the board product portion. The effect of being able to provide.

[Brief description of drawings]

FIG. 1 is a plan view of a printed circuit board showing an embodiment of a printed circuit board structure according to the present invention.

FIG. 2 is a sectional view taken along line I-I of FIG.

[Explanation of symbols]

10 printed circuit boards 10A Product Department 10B Discarded board part 11A, 11B V groove (groove) 12, 12A-12E Front and back through holes 13 Electronic components

Claims (3)

[Claims] 1. A structure of a printed circuit board, which is divided into a product section on which an electronic component is mounted and a discarded board section to be removed, the groove being provided on a dividing line of the printed circuit board and along the groove. The printed circuit board structure is characterized in that a plurality of front and back through holes penetrating in the front and back direction of the printed circuit board or a plurality of bottomed holes opened on the mounting side of the electronic component are formed. 2. The printed circuit board structure according to claim 1, wherein the front and back through holes or the bottomed holes are arranged in a continuous state without a gap. 3. The printed circuit board structure according to claim 1, wherein the front and back through holes or the bottomed holes are selectively arranged with respect to the electronic component.