Positioning method and board

Abstract

Disclosed are a positioning method and a board for swiftly and accurately adjusting the position of a warpage-preventive rail for preventing warpage of the board in flow soldering. A mark of a width B provided with a slit having a width A in a direction perpendicular to a dip direction indicated by an arrow is silk-screen printed at an end of a surface opposite to a flow solder surface of a board. The width B of the mark is set to such a value that an operator who adjusts the position can easily recognize the mark. The slit is formed on a surface opposite to a support band where the upper surface of the warpage-preventive rail supports the board, and the width A of the slit is set to a value approximately equal to the width of the upper surface of the warpage-preventive rail.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings,

FIG. 1 is an illustration showing a board according to a first embodiment of the present invention;

FIG. 2 is a top view illustrating the positions of the board according to the first embodiment of the invention and a warpage-preventive rail;

FIG. 3 is a perspective view illustrating the positions of the board according to the first embodiment of the invention and the warpage-preventive rail;

FIG. 4 is an illustration showing a board according to a second embodiment of the invention;

FIG. 5 is a top view illustrating the positions of the board according to the second embodiment of the invention and the warpage-preventive rail;

FIG. 6 is a perspective view illustrating the positions of the board according to the second embodiment of the invention and the warpage-preventive rail;

FIG. 7 is a top view illustrating the positions of the board according to the second embodiment of the invention and the warpage-preventive rail;

FIG. 8 is a perspective view illustrating the positions of the board according to the second embodiment of the invention and the warpage-preventive rail;

FIG. 9 is a perspective view showing the warpage-preventive rail;

FIG. 10 is a longitudinal sectional view of the warpage-preventive rail;

FIG. 11 is a bottom view showing a board according to a conventional technique; and

FIG. 12 is a top view illustrating the positions of the board according to the conventional technique and the warpage-preventive rail.

Claims

1. A positioning method of a warpage-preventive rail for supporting a board from below to prevent downward warpage of the board when a component is flow-soldered onto the board in a molten solder bath, the positioning method comprising the steps of: forming a mark provided with a slit having a width approximately equal to a width, perpendicular to a dip direction, of a surface of the warpage-preventive rail facing the board, at an end of a surface opposite to a flow solder surface of the board; andadjusting a position of the warpage-preventive rail to the slit.

2. A positioning method of a warpage-preventive rail for supporting a board from below to prevent downward warpage of the board when a component is flow-soldered onto the board in a molten solder bath, the positioning method comprising the steps of: forming a notch having a width approximately equal to a width, perpendicular to a dip direction, of a surface of the warpage-preventive rail facing the board, at an end of a surface opposite to a flow solder surface of the board;forming a mark around the notch; andadjusting a position of the warpage-preventive rail to the notch.

3. The positioning method according to claim 1 or 2, wherein the mark is formed by silk-screen printing.

4. A board that is supported from below by a warpage-preventive rail for preventing downward warpage of the board when a component is flow-soldered onto the board in a molten solder bath, the board comprising: a mark provided with a slit having a width approximately equal to a width, perpendicular to a dip direction, of a surface of the warpage-preventive rail facing the board, at an end of a surface opposite to a flow solder surface of the board.

5. A board that is supported from below by a warpage-preventive rail for preventing downward warpage of the board when a component is flow-soldered onto the board in a molten solder bath, the board comprising: a notch having a width approximately equal to a width, perpendicular to a dip direction, of a surface of the warpage-preventive rail facing the board, at an end of a surface opposite to a flow solder surface of the board; anda mark formed around the notch.

6. The board according to claim 4 or 5, wherein the mark is formed by silk-screen printing.