| 摘要 |
PROBLEM TO BE SOLVED: To provide a sewing machine needle capable of surpress needle breakages during sewing, preventing the minute pieces of the needle from flying at the time of the breakage and enhancing the safety in the sewing work and the sewn products. SOLUTION: A needlepoint part 1, a needle eye part 2, a hollowed part 3, a needle blade part 4, a taper part 5 and a shank part 6 are formed from a metal needle material comprising carbon steel, and the needle blade part 4 comprises the first needle blade part 41 with a small diameter that is continuous with the needlepoint part 1 and the second needle blade part 42 with the diameter larger than the first needle blade part 41 continued with it at the small taper part 7 and smaller than the shank part 6. The hardness of the entire needle is made 800 Hv or below by heat treatment, and a chrome plate 9 is provided. A needle has such a constitution that it is provided with baking treatment in such a manner that the proper break point angle at the time of needle breakage is 15 deg. or below.
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