(i) Technical Field
The present invention relates to a printed circuit board unit.
(ii) Related Art
Japanese Patent Application Publication No. 2010-130723 discloses a technique where a terminal pin is inserted into a through hole of the printed circuit board to join both of the terminal pin and the printed circuit board by soldering. The terminal pin is formed with a protruding portion to be inserted into the through hole, in order to stand the terminal pin inserted into the through hole before being jointed to the printed circuit board by soldering.
However, the molten solder may not be sufficiently filled around the protruding portion depending on the shape of the protruding portion. Thus, the solder may be solidified with containing a bubble near the protruding portion. In such a case where the solder is solidified with containing the bubble near the protruding portion, the solder may be cracked by vibration or the like. Further, this may influence the conductivity between the terminal pin and a pattern of the printed circuit board.