| 摘要 |
PURPOSE:To manufacture a titled pipe having no looseness in the circumferential direction of a fin, by winding an L-shaped bandlike fin material around the outside circumference of the pipe, and continuously engaging with each adjacent fin by a pair of left and right sawtooth edges and a cutting edge moving along its center part. CONSTITUTION:A spiral cooling fin 2 is wound around a magnetron ball body 1. Subsequently, two fins whose end parts are adjacent are cut-bent simultaneously by use of a cut-bending fin guide and a cut-bending cutter, and the end parts of a winding start 3a and a winding end 3b are fixed. Subsequently, the body 1 is fixed by inserting all pitches of the fin 2 into groove parts of a pair of left and right cut-raising sawtooth edges 7a, 7b. Thereafter, a cut-raising moving edge 9 fixed to a slide base 8 so as to be positioned in the center part of the edges 7a, 7b is moved along guide shafts 10a, 10b. In this way, a notch is formed continuously in the adjacent fins 2 and is bent simultaneously, and a cut-raised part 4 is formed. |
