JPS5825019A - Circuit board and method of producing same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circuit board having switch electrodes on the side surface of the board and its manufacture.

BACKGROUND ART Conventionally, circuit boards having switch electrodes formed on the side surfaces of the boards have been used particularly as platforms for watches that are required to be smaller and thinner. In that case, in order to reduce the number of parts, steps, and thickness, a metal conductive process called so-called side through hole is used, but the side electrode part is shown in Figure 1 (
g) was common. That is, the pattern 2 is formed on the outer periphery and the surface of the circuit board 1, and the switch electrode portion 2I
IB had a through-hole inner surface shape that was close to a simple plane. However, in such an electrode part 2-, when the switch contact lever ink moves in the direction of the arrow to perform switching as shown in Fig. 2, it is not determined which part of the switch electrode part 2-0 will come into contact with the tip of the lever sO. Also, the reliability is poor if the contact is close to surface contact (there were many design concerns).

The present invention eliminates the above problems.
The purpose is to provide a circuit board and its manufacturing method in which the switch terminal electrode is formed at the intersection of two circular arcs, to make the contact area with the switch contact lever constant, and to prevent malfunction due to poor contact. The goal is to realize a circuit board.

The present invention will be described in detail below with reference to the drawings.

FIG. 3 shows an embodiment of the circuit board according to the present invention, 11
12 is a circuit board, 12 is a pattern extending toward the outer mva surface 11#1 of the board 11, 12g is a metal land for a side through hole formed through a metal conductor process, and 12h is a peripheral switch consisting of the intersection of two circular arcs. This is a terminal electrode for use. The terminal electrode 12h is connected to a circuit component terminal such as an IO (not shown) via the land 12m and the pattern 12.

The shape of the terminal electrode is as shown in #41iU on the substrate 2.
Electrode portions 22g and 22A formed on the outer peripheral side surface 21α of 1
, 22c, and 22dO.

Next, the switch operation will be explained based on the terminal electrode 12A shown in FIG.

FIG. 5 shows the terminal electrode 12 of FIG. In the enlarged view of h, 13 is a contact lever having spring properties that contacts the terminal electrode 12h, and 14 is an operating arm that presses the contact lever 15. Now, when the operating arm 14 is pushed in the direction of the arrow via the external operating member, the contact lever 11 is bent to the position shown by the two-dot chain line against the elastic force. At this time, the substrate 11
Since the terminal electrode 124 forming the switch part is located at the intersection of two circular arcs, the contact lever 13 always comes into contact with the sharp tip of the terminal electrode 12A, so the switching position is at the intersection of the two circular arcs. It can be determined by the shape, and
Contact is reliable.

Next, based on FIGS. 6(-) to 9(6) and their cross-sectional views FIGS. 6(b) to 9(b), we will explain the manufacturing process of the side switch terminal electrode according to the present invention. An example will be described.

In the step shown in FIG. 6(g) I Cb), the base material is an example of a steel-clad laminate, and first, a thickness of 18 μm is applied to both sides of the base material 11.
Two holes 31 and 52 are drilled at the positions of the switch terminal electrodes 12b on the outer peripheral side of a laminate plate with a copper cladding 3o of about 100 mL. Next, in FIGS. 7(-) and 7(h), copper plating 12 is applied to the entire surface of the substrate, and in the step shown in FIG. Then, apply anti-corrosion plating such as gold plating to the copper metal surface. In the case of a single-pole switch on the inner side of the substrate, it can be used as a side switch as it is, but for the outer periphery side switch terminal electrode according to the present invention, the following steps shown in FIGS. 9 (IL) and (h) are performed. pass In the ninth [(g), Cb), in order to arrange the outer peripheral side switch terminal electrode 12b in the substrate shape as shown in FIG. By dividing the two intersecting arcs 51 and 52 shown in (a), the side switch terminal electrode 12b is opened to the outer peripheral surface 11g as shown in FIG.
can be obtained.

In addition, *t1s indicates the order and positional relationship of drilling holes in the two circular arcs 51 and 32, and prevents burrs from adhering to the base material on the portion 12 that will become the side switch terminal electrode.
If the drill rotates clockwise as shown by the arrow, first,
After drilling the hole 52, the hole s1 is drilled to make the shape of the portion 12b that will become the electrode described above constant (if the drill rotates counterclockwise, the order is reversed). Further, since the hole 32 is drilled in advance, the drill may shift in the direction of the hole 52 when drilling the hole 31. Therefore, the center position P of the hole 51 is moved to the q position by 57. o. ++ 10/. .

(■) Correcting the illumination (setting it so that it corresponds to the dotted line circle position) will ensure accuracy.

As described above, according to the present invention, it is possible to obtain a small, thin circuit board for electronic equipment, a high-quality and inexpensive circuit board having switch terminal electrodes, and a method for manufacturing the same.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a perspective view of a conventional circuit board, FIG. 2 is a plan view showing switch operation of the conventional circuit board, and FIG. 5 is a plan view showing an embodiment of the present invention. 4gJ is a plan view showing another embodiment of the present invention, FIG. 5 is a plan view showing the operation of one embodiment of the present invention, and FIG. 6(a). (A)--FIGS. 9(a) and (b) are a plan view and a cross-sectional view showing the manufacturing process of the present invention, and FIG. 10 is a perspective view of a terminal electrode portion according to the present invention, and FIG. 11 is a plan view illustrating the process order of arc formation. 11...Circuit board 12...Wiring pattern 12@...Rand fist pattern 12b...Switch terminal electrode 51,! 2...Two circular arcs. Applicant Seiko Keiyo Kogyo Co., Ltd. Kinsha Agent Patent Attorney Mogami Figure 1 Figure 20 1EaB 56IIIJ (cA) ll 8th ca') Figure 8 (do) ++ 32 Figure 7 yJ (a) Figure 187 ( &P) 2 2 91st Mrα notse diagram (persimmon

Claims (1)

[Claims] (1) A circuit board in which a terminal electrode for a switch is formed on a side surface of the board through a metal conductor process, wherein the terminal electrode is formed at the intersection of two circular arcs. (to)) A method of manufacturing a circuit board, wherein the two arcs are formed through a drilling process using a cone. (1) In the process of drilling holes with the bell, the post-process is performed in such a way that the direction in which the drill bit penetrates is in the opposite direction to the rotation direction of the drill bit relative to the outer periphery of the substrate, and burrs occur at the intersection of the two circular arcs. 3. The method of manufacturing a circuit board according to claim 2, wherein the circuit board is manufactured in such a manner that the circuit board is not damaged.