| 摘要 |
The conventional lead member had a constant thickness in a section parallel to a longitudinal direction, so that it has found it difficult to enlarge a joint area with a soldering material. Therefore, the lead member itself has to be enlarged so as to enlarge the contact area which contributes to the joining property between the lead member and the soldering material. In a section parallel to the longitudinal direction of a lead member (11) and containing the center axis (A) of the lead member (11), the distance from one point (X) of the soldered portion of the outer circumference of the lead member (11) to the center axis (A) of the lead member (11) is made shorter than the distance from another point (Y) of the soldered portion to the center axis (A), so that the contact area between the lead member (11) and the soldering material can be enlarged. |
