JP2008060327A - Method of mounting substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To arrange a substrate manufactured by a flow soldering process and a substrate manufactured by a reflow soldering process a single dividable printed circuit board, without the constraints for the layout. <P>SOLUTION: Each surface-mount component is mounted onto the printed circuit board coated with a thermosetting adhesive and cream solder, and the thermosetting adhesive and cream solder are hardened by a heating furnace so as to fix each surface-mount component onto the printed circuit board. Then, the printed circuit board is divided; a lead insertion component is further mounted only onto some of the divided printed circuit boards; and the divided printed circuit boards respectively mounted with each lead insertion component are immersed into a solder tank, so as to secure electrical conduction, while fixing the lead insertion component and the surface-mount component to each printed circuit board. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate mounting method for mounting an electronic component on a printed circuit board and fixing the electronic component to the printed circuit board and ensuring electrical conduction.

  Since a printed circuit board is an industrial product, a size that can be cut without waste from a size that is produced in large quantities is inexpensive, and waste generation is also low.

  However, there are cases where the size of the printed circuit board cannot be cut out without waste due to regulations such as the size of the final product. In this case, it is conceivable to combine several types of substrates used for the final product into one printed circuit board. After this substrate is divided, the substrate can be mounted.

  Further, there is a means for dividing after mounting on the board, which is disclosed in Patent Document 1. If this method is adopted, the substrate mounting process is completed once.

  Soldering is the most common means for mounting electronic components on a printed circuit board to ensure electrical continuity.

  As is well known, soldering is performed by applying cream solder to a printed circuit board and thermally curing it in a heating furnace, and soaking the soldered surface of the printed circuit board in a solder bath containing molten solder. There is a so-called flow soldering process. Substrate mounting is performed using these steps alone or in combination.

For example, a reflow soldering process is used when only surface mounting components are mounted on only one side of a printed board. Alternatively, when mounting a surface mounting component on one side of the printed circuit board and a lead insertion component on the other side, the following steps are performed.
(1) Application of adhesive to printed circuit board (2) Surface mounting component mounting (3) Surface mounting component is fixed to printed circuit board by thermosetting furnace (4) Lead insertion component mounting (5) Flow soldering process

  An example of a more complicated combination in one printed circuit board is described in Patent Document 2.

This document is characterized in that a strip-shaped lead insertion component placement region is disposed in one printed circuit board, and only the strip-shaped lead component placement region is infiltrated into the solder tank after the reflow process, and flow soldering is performed.
JP 2004-47871 A JP-A-11-284306

  However, with the method disclosed in Patent Document 1, only substrates having the same type of process can be collected on a single printed circuit board.

  In addition, when the technique disclosed in Patent Document 2 is used, a board having a plurality of processes can be integrated into one printed board and manufactured in a series of mounting processes. Must be placed.

  The present invention has been made in view of the circumstances as described above, and layout restrictions are imposed on a substrate that is manufactured by a flow soldering process and a substrate that is manufactured by a reflow soldering process on one separable printed circuit board. The purpose is to arrange without.

In order to achieve the above object, the present invention provides:
In a board mounting method for mounting electronic components on a single printed board that can be divided into a plurality of boards,
A surface mounting component is mounted on the printed circuit board to which the thermosetting adhesive and the cream solder are applied through the process of applying the thermosetting adhesive to the printed circuit board and the process of applying the cream solder to the printed circuit board. Process,
A step of curing the thermosetting adhesive and the cream solder by heating by a heating means and fixing the surface mount component to the printed circuit board;
Dividing the printed circuit board;
A step of further mounting lead insertion parts only on a part of the printed circuit boards after the division,
Fixing the lead insertion component and the surface mount component to the printed circuit board by infiltrating a part of the printed circuit board after the division into a solder bath, and ensuring electrical conduction;
It is characterized by including.

  According to the present invention, it is possible to arrange a substrate manufactured by a flow soldering process and a substrate manufactured by a reflow soldering process on one separable printed circuit board without any layout restrictions.

  The best mode for carrying out the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in this embodiment should be appropriately changed according to the configuration of the apparatus to which the invention is applied and various conditions. It is not intended to limit the scope to the following embodiments.

  FIG. 1 is a diagram showing a flow of steps for explaining a substrate mounting method according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a printed board that is mounted by the board mounting method according to the present embodiment. In addition, in order to avoid the complexity of a figure, illustration of a copper foil pattern is abbreviate | omitted.

  In FIG. 2, 101 is a printed circuit board. The printed circuit board 101 may be a single-sided, double-sided, or multilayer board.

  A perforation 102 exists on the printed circuit board 101. The printed circuit board 101 can be divided into a perforation 102 portion, a portion indicated by 101a (hereinafter referred to as a portion 101a), and a portion indicated by 101b (hereinafter referred to as a portion 101b).

  Reference numeral 103 denotes a hole into which a lead of a lead insertion component is inserted.

In the present embodiment, mounting is performed in the part 101a by a flow soldering process and in the part 101b by a reflow soldering process.

  Hereinafter, description will be made according to the flow of FIG.

  First, cream solder is applied to the printed circuit board 101 (S1). The printed circuit board 101 in this state is shown in FIG.

  In FIG. 3, reference numeral 104 denotes cream solder. If the cream solder 104 is applied only to the portion 101b where the reflow process is performed, the cream solder is not wasted.

  Next, a thermosetting adhesive is applied to the printed circuit board 101 (S2). The printed circuit board in this state is shown in FIG.

  In FIG. 4, reference numeral 105 denotes a thermosetting adhesive. In the case of the present embodiment, the thermosetting adhesive is applied only to the portion 101a where the flow process is performed.

  Note that the order of the two steps may be reversed.

  Next, a surface mounting component is mounted on the printed circuit board 101 (S3). The printed circuit board in this state is shown in FIG.

  In FIG. 5, the shape of 106 is a chip resistor or a chip ceramic capacitor, the shape of 107 is a surface mount type IC, and 108 is a surface mount type connector.

  Next, the printed circuit board 101 in the state of FIG. 5 is put into a thermosetting furnace as a heating means (S4).

  As a result, the thermosetting adhesive and the cream solder are cured.

  The surface mount component mounted on the portion 101a is fixed to the printed circuit board 101 by the curing of the thermosetting adhesive. In addition, the portion 101b is a reflow process, and the mounted surface-mounted component is fixed to the printed circuit board 101 by curing the cream solder, and electrical conduction is ensured.

  Thereafter, the printed circuit board 101 is divided into portions 101a and 101b at the perforated portion 102 as shown in FIG. 6 (S5).

  The portion 101b is completed in this embodiment (S6).

  After that, the part 101a is mounted with lead insertion parts (S7), and a flow soldering process is performed (S8, the soldering surface of the printed circuit board is infiltrated into a solder bath containing molten solder), and the part 101a is completed (S9). ).

  A substrate completed by applying the substrate mounting method of this embodiment is shown in FIGS. FIG. 7 is a view of the portion 101a as seen from the component surface side. FIG. 8 is a view of the portion 101a as viewed from the solder surface side. FIG. 9 is a side view of the portion 101a. FIG. 10 is a view of the portion 101b as seen from the component surface side. FIG. 11 is a view of the portion 101b as seen from the solder surface side. FIG. 12 is a side view of the portion 101b.

110 is a DIP package IC, 111 is a lead resistor, 112 is a transistor,
113 is a connector, and 114 is an electrolytic capacitor.

  As described above, according to the present embodiment, the mounting board created in the flow soldering process and the mounting board created in the reflow soldering process are formed on one printed board without increasing the number of mounting steps. Can be mixed without any restrictions.

  In this embodiment, the case where the printed circuit board 101 is divided into two parts 101a and 101b has been described. However, the present invention is not limited to this. The present invention can be suitably applied to a single printed circuit board that can be divided into a plurality of boards. One printed circuit board is printed by the above-described board mounting method, (1) a printed circuit board that is divided and completed after the reflow process, and (2) a printed circuit board that is completed by performing a flow soldering process with lead insertion components mounted after the dividing process. The substrate is divided into a plurality of substrates classified into two.

  In the present embodiment, the portion 101b has surface mounting components mounted on only one surface, but surface mounting components can also be mounted on both surfaces. In that case, the thermosetting adhesive is applied also to the portion 101b in the thermosetting adhesive application step, and after the substrate is divided, the cream solder application, the surface mounting component mounting, and the thermosetting furnace are added.

The figure which shows the flow of the process for demonstrating the board | substrate mounting method which concerns on the Example of this invention. The figure which shows the printed circuit board mounted by the board | substrate mounting method which concerns on the Example of this invention. The figure which shows the state which applied the cream solder application to the printed circuit board shown in FIG. The figure which shows the state which apply | coated the thermosetting adhesive to the printed circuit board shown in FIG. The figure which shows the state which mounted the surface mounting components on the printed circuit board shown in FIG. The figure which shows the state which divided | segmented the printed circuit board shown in FIG. The figure which shows the board | substrate completed by applying the board | substrate mounting method based on the Example of this invention. The figure which shows the board | substrate completed by applying the board | substrate mounting method based on the Example of this invention. The figure which shows the board | substrate completed by applying the board | substrate mounting method based on the Example of this invention. The figure which shows the board | substrate completed by applying the board | substrate mounting method based on the Example of this invention. The figure which shows the board | substrate completed by applying the board | substrate mounting method based on the Example of this invention. The figure which shows the board | substrate completed by applying the board | substrate mounting method based on the Example of this invention.

Explanation of symbols

101 Printed circuit board 101a part (part where mounting is performed in the flow soldering process)
101b part (part where mounting is performed in the reflow soldering process)
102 perforation 104 cream solder 105 thermosetting adhesive

Claims (2)

In a board mounting method for mounting electronic components on a single printed board that can be divided into a plurality of boards,
A surface mounting component is mounted on the printed circuit board to which the thermosetting adhesive and the cream solder are applied through the process of applying the thermosetting adhesive to the printed circuit board and the process of applying the cream solder to the printed circuit board. Process,
A step of curing the thermosetting adhesive and the cream solder by heating by a heating means and fixing the surface mount component to the printed circuit board;
Dividing the printed circuit board;
A step of further mounting lead insertion parts only on a part of the printed circuit boards after the division,
Fixing the lead insertion component and the surface mount component to the printed circuit board by infiltrating a part of the printed circuit board after the division into a solder tank, and ensuring electrical conduction;
A substrate mounting method comprising:   2. The substrate mounting method according to claim 1, wherein cream solder is not applied to a portion of the printed board that is to be infiltrated into the solder tank after the division.

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