| 摘要 |
<p>PURPOSE:To increase the strength of the welded section of a ring against metal fatigue by forming a wide-width circular groove on the outer periphery of a fixed core on the side opposite to the ring adjacent to the welded section and a narrow-width circular groove on the outer periphery of the small path section of the fixed core on the inside of the ring adjacent to the welded section. CONSTITUTION:When a fixed core 1 and ring 2 are welded to each other by, for example, TIG welding, the welded section 10 of the core 1 first starts to gradually melt from the side nearer to the welding electrode. The welding heat is transferred toward the center of the core 1, since a wide-width circular groove 8 blocks the transfer of the heat in the lateral direction. The transfer of the heat toward the center of the core 1 is blocked by a narrow-width circular groove 9 and turned toward the inside of the core 1. As a result, the stress concentration point 18 of the welded section 10 moves toward the inside of the core 1. Since the distance 19 between the point 18 and the outer peripheral surface of the core 1 becomes considerably longer than the thickness 22 of the ring 2, the strength of the welded section 10 of the ring 2 against metal fatigue becomes five times stronger than the conventional example.</p> |
