| 摘要 |
PURPOSE:To prevent loosening of a caulked section, by caulking the section in such a manner as to embed a projecting strip, which is provided on outside circumferential edge of bottom surface of a contact pellet, into tip surface of a main body in order to ensure accuracy of positioning of the contact pellet with respect to the main body. CONSTITUTION:A projecting strip 1, whose outside circumferential surface is vertical and inside circumferential surface is sharply angled, is formed along outside circumferential edge of bottom surface of a bowl-sectionlike contact pellet 2, and by being kept in the condition that this projecting strip 1 is embedded into tip surface of a main body 3 and spread toward outside, an annular rib 4 which was formed on outside circumferential section of tip surface of a screw's main body 3 is caulked toward outside circumferential section of top surface of the contact pellel 2. As it is possible, by doing this, to keep the contact pellet 2's projecting strip 1 embedded into the main body 3's tip surface even at the time when caulking between the annular rib 4 and the contact pellet is loosened, and therefore, the contact pellet 2 can be prevented from shifting and enabled to serve the purpose satisfactorily for a long period of time. |
