JPH0634285U - Printed wiring board - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a printed wiring board which is excellent in soldering strength of electronic parts, has a large peeling resistance between the board and the conductive layer in its mounting portion, has high reliability, and is easy to manufacture. . [Structure] In a printed wiring board 1 having an insulating layer 3 provided on a surface on which wiring 2 is provided, a peripheral edge 5a of a conductive layer exposed portion 5 surrounding a terminal pin insertion hole 4 of the board 1 goes in and out of a surrounding insulating layer 3. The terminal pin 7 of the electronic component, which is formed into a shape and passes through the terminal pin insertion hole 4, is connected to the conductive layer 2a of the exposed portion 5 by soldering 6.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a printed wiring board used in electric circuit parts of various electric / electronic devices.

[0002]

[Prior art]

 In general, a printed wiring board has terminal pin insertion holes that penetrate the front and back of the board at the points where the printed wiring of a specified pattern made of copper, silver, or the like is provided on one or both sides of the insulating board. By soldering terminal wires of various electronic parts through these insertion holes, the electronic wires are electrically connected to the printed wiring and the electronic parts are attached to the board.

Then, conventionally, as shown in FIGS. 5 and 6, the surface of the insulating substrate 1 on which the printed wiring 2 is formed is covered with an insulating layer 3 having no adhesiveness to solder, and each terminal pin is inserted. A circular conductive layer exposed portion 5 which is not covered with the insulating layer 3 is formed around the hole 4, and the substrate 1 is immersed in the solder solution while the terminal pins of the electronic component are passed through the terminal pin insertion holes 4. By doing so, a method of simultaneously soldering the terminal pins in each insertion hole 4 is adopted. FIG. 7 shows a state after soldering, in which the solder 6 fixes the terminal pins 7 to the substrate 1 in such a manner that the exposed portions 5 of the conductive layer and the terminal pin insertion holes 4 are filled with the conductive layer of the printed wiring 2. 2a and the terminal pin 7 are electrically connected via the solder 6.

[0004]

[Problems to be solved by the device]

 By the way, since the electronic components attached to the printed wiring board are held by the terminal pins 7 in a protruding manner on the substrate 1, they often come into contact with other articles during handling of the printed wiring board. Stress always concentrates on the soldered portion of the terminal pin 7. However, in the conventional printed wiring board, since the fixing strength of the solder 6 to the board 1 and the holding strength of the terminal pin 7 by the solder 6 are insufficient, the conductive layer 2a is integrated with the solder 6 from the board 1 during handling. There have been many problems such as peeling and causing conduction failure, and the terminal pin 7 coming off from the substrate 1 and failing to fulfill the required function of the electronic component. However, conventionally, after performing the above-mentioned collective soldering by dipping, solder 6 is individually manually repaired to increase the holding strength of the terminal pin 7 at a soldering place where a problem is particularly likely to occur. That is, a very troublesome method is also adopted.

In view of the above situation, the present invention is excellent in soldering strength of electronic parts, has a large peeling resistance between the substrate and the conductive layer at the mounting portion, has high reliability, and is packaged by immersion. The purpose is to provide a printed wiring board that does not require repairing operations after soldering.

[0006]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention provides a printed wiring board 1 having an insulating layer 3 on the surface on which wiring 2 is provided, and a peripheral edge 5a of a conductive layer exposing portion 5 surrounding a terminal pin insertion hole 4 of the board 1. Is formed in and out of the surrounding insulating layer 3, and the terminal pin 7 of the electronic component passed through the terminal pin insertion hole 4 is connected to the conductive layer 2a of the exposed portion 5 by soldering 6. The following configuration is adopted.

[0007]

[Action]

 In the printed wiring board of the present invention, since the peripheral edge of the conductive layer exposed portion 5 surrounding the terminal pin insertion hole 4 of the printed wiring board 1 is formed in and out of the surrounding insulating layer 3, the exposed portion 5 is exposed. The burying solder 6 is in contact with the insulating layer 3 with a long peripheral line length, and the part that enters into the insulating layer 3 acts as an anchor, so that the fixing strength of the solder 6 to the substrate 1 and thus the resistance of the insulating layer 2a in the exposed part 5 are improved. The peel strength is significantly increased as compared with the conventional circular exposed portion.

Further, in manufacturing the printed wiring board, the terminal pins 7 of the electronic component are inserted into the terminal pin insertion holes 4 of the substrate 1 and then immersed in a solution of solder to form the insertion holes 4 in the insertion holes 4. When the terminal pins are soldered at the same time, the conductive layer exposed portion 5 has the above-described inward and outward peripheral edges, so that the resistance against the flow of the solder solution becomes large at the peripheral edges, and the amount of solder adhered is smaller than that of the conventional circular shape. Compared with the exposed part, the soldering strength of electronic parts increases correspondingly, and the conventional repair by soldering after dipping becomes unnecessary.

[0009]

【Example】

 FIG. 1 (A) is a cross-sectional view showing an essential part of a printed wiring board according to the present invention, in which the surface of the insulating substrate 1 on which the printed wiring 2 is formed is covered with an insulating layer 3 which does not adhere to solder. However, the periphery of the terminal pin insertion hole 4 becomes a conductive layer exposed portion 5 which is not covered with the insulating layer 3, and the conductive layer exposed portion 5 and the terminal pin insertion hole 4 are filled by immersion in a solder solution. The attached solder 6 fixes the terminal pin 7 of the electronic component inserted in the terminal pin insertion hole 4 to the substrate 1, whereby the conductive layer 2a of the printed wiring 2 and the terminal pin 7 are connected via the solder 6. It is electrically connected.

Here, as shown in FIG. 1B, the conductive layer exposed portion 5 has a substantially circular shape concentric with the terminal pin insertion hole 4, and its peripheral edge is recessed toward the insulating layer 3 side at regular intervals. The rectangular concave portion 5a is formed into and out of the insulating layer 3. As a result, the printed wiring board shown in FIG. 1 (A) has a higher mountain shape centered on the terminal pins 7 with a larger amount of solder 6 attached, as compared with the printed wiring board of the conventional configuration shown in FIG. I am doing it.

The peripheral shape of the conductive layer exposing portion 5 which is in and out of the insulating layer 3 is not limited to that shown in FIG. 1B, and for example, the insulating layer 3 is arranged at regular intervals as shown in FIG. Shape having a conical recess 5b that is recessed to the side, a shape having a gear-like contour 5c on the entire periphery as shown in FIG. 3, and protruding from the insulating layer 3 side to the exposed portion 5 side at regular intervals as shown in FIG. Various settings can be made, such as the shape provided with the conical protrusion 5d. Further, the outline of the conductive layer exposing portion 5 is not limited to the circular shape, but may be variously set such as an elliptical shape or a rectangular shape.

[0012]

EFFECTS OF THE INVENTION According to the present invention, the soldering strength of electronic parts is excellent, the peeling strength between the substrate and the conductive layer at the mounting portion is large, and the reliability is high. (EN) Provided is a printed wiring board which does not require a repair operation after being attached and is easily manufactured.

[Brief description of drawings]

FIG. 1A is a longitudinal cross-sectional view of a main part of a printed wiring board according to an embodiment of the present invention, and FIG. 1B is a main configuration example of a conductive layer exposing part of a printed wiring board used for the same wiring board. FIG.

FIG. 2 is a plan view of an essential part showing a second configuration example of a conductive layer exposed part.

FIG. 3 is a main-portion plan view showing a third configuration example of the conductive layer-exposed portion.

FIG. 4 is a plan view of a main part showing a fourth configuration example of a conductive layer exposed part.

FIG. 5 is a plan view of a principal portion showing a conductive layer exposed portion of a conventional printed wiring board.

6 is a cross-sectional arrow view taken along the line VI-VI of FIG.

FIG. 7 is a vertical cross-sectional view of a main part of a conventional printed wiring board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating substrate 2 Printed wiring 2a Conductive layer 3 Insulating layer 4 Terminal pin insertion hole 5 Conductive layer exposed part 5a Square concave part 5b Conical concave part 5c Gear-shaped contour 5d Conical protruding part 6 Solder 7 Terminal pin

Claims (1)

[Scope of utility model registration request] 1. A printed wiring board having an insulating layer formed on a surface on which wiring is provided, wherein a peripheral edge of a conductive layer exposed portion surrounding a terminal pin insertion hole of the board is formed in and out of a surrounding insulating layer, A printed wiring board in which terminal pins of an electronic component passed through the terminal pin insertion holes are connected to the conductive layer of the exposed portion by soldering.