| 摘要 |
PURPOSE:To simplify the production process and to unify the quality by punching a small ring and guard bars from a sheet of metallic plate so as to form them concurrently in one body. CONSTITUTION:A zigzag cutout 7 is punched on a rectangular metallic plate 6 leaving belt strips 6a with a little width on both sides in the lengthwise direction, thus forming comb teeth 6b. Next, the belt strip 6a is vertically bent and is curved in a circle to form a small ring 9, and the comb teeth 6b are radially extended to form guard bars 10. After the guard bars 10 are bent into nearly an L-shape, a large ring 11 is welded and fixed to their tips. When two large rings 11 of half-guards are joined together, a main guard is obtained, thereby the production process can be simplified and rationalized and the productivity can be remarkably improved, and also the uniformity of the product can be improved. |
