| 摘要 |
PURPOSE:To manufacture a tooth profile product holding a long punching life by using a female die in tooth profile having a mirror face with tapered inlet port by setting to the lower part shape of a bossed blank and the punch setting to the upper face shape of the blank. CONSTITUTION:The bossed blank 3 prepd. in advance is placed between a punch 1 and female die 2 to push the punch 1 down to the lower part. The lower part shape of the punch 1 is of the shape set to the upper part shape of the blank 3 and there is no gap between the blank 3 and punch 1, so a forming metal is sufficiently led to the tooth crest of the blank 3. The taper at the angle of 20-150 deg. is provided at the inlet port of the female die 2 and yet formed in a mirror face, so the blank 3 is passed through with less friction resistance and the surface of a tooth profile product 3' is smoothly formed. Moreover the press pressure of the punch 1 is dispersed by the taper and the working can be performed by reducing pressure for the female die 2 and punch 1 and the counter bearing of the punch 1 is less, so the die life is further extended. |
