To easily manufacture the sewing machine needle of high quality provided with buckling rigidity sufficient as the sewing machine needle for hardly causing breakage accidents, to improve productivity as well and to manufacture it at a low cost by press-molding the needle trunk part of the sewing machine needle without forming burrs at the needle trunk part.
A thread groove 5 is turned to a curved bottom surface recessed groove 11 whose bottom surface is curved in a circular arcuate shape from a part near a needle hole toward a handle part close to the part corresponding to the tip part of a back groove provided on the opposite side of the thread groove and is provided with a flat bottom surface recessed groove 12 whose bottom surface is turned to a flat shape through the part for smoothly changing from the curved bottom surface 11 to the tapered part of the handle part. Thus, this needle of the high quality provided the sufficient buckling rigidity for hardly causing the breakage accidents is provided. Also, since a gap between a needle trunk and a sewing thread is secured large, stable sewing work is performed and a high-speed operation is made possible as well.
| JP04088149 | NEEDLE FOR TEXTILE MACHINERY |
| JP11057272 | HAND SEWING NEEDLE AND ITS MANUFACTURE |
| WO/2010/114453 | NEEDLE |
Hotta, Hiroshi
