| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a broach that prevents damage to a cutting blade, and whose service life is easily determined, while reducing the number of manufacturing man-hours and a manufacturing cost of the broach. <P>SOLUTION: The broach 1 includes a roughing part 10 and a finishing part 20. Land widths 201a, 202a, 203a of cutting blades 201, 202, 203 of the finishing part 20 are gradually reduced toward a final cutting blade 300 side of the broach 1. Land widths 101a, 102a, 103a of the cutting blades 101, 102, 103 of the roughing part 10 may be gradually increased toward the finishing part 20. Further, blade groove widths 201b, 202b, 203b between the cutting blades 201, 202, 203 of the finishing part 20 may be reduced toward the final cutting blade 300 side of the broach 1, while being increased and decreased. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
