METHOD FOR MANUFACTURING FORGED CRANKSHAFT

WIPO Patent Application WO/2019/146511

A1

This method for manufacturing a forged crankshaft includes a first preliminary molding step for obtaining an initial rough forging (23) from a billet (22), a second preliminary molding step for obtaining a final rough forging (24) from the initial rough forging (23), and a finishing forging step. The first preliminary molding step includes: a step in which a pair of first molds (40) are used to press sites that are to form a plurality of journal portions, pressing being performed from the direction perpendicular to an axial direction of the billet (22), whereby a plurality of flat portions (23a) are formed; and a step in which, after the start of pressing by the first molds (40), a second mold (50) is used to cause sites that are to form first pin portions and sites that are to form third pin portions to become eccentric in mutually opposite directions. In the second preliminary molding step, a pair of third molds (30) are used to press the plurality of flat portions (23a), the sites that are to form the first pin portions, sites that are to form second pin portions, and the sites that are to form the third pin portions, the width direction of the flat portions (23a) being used as the pressing direction. In the final rough forging, the thickness of sites that are to form a plurality of crank arm portions is the same as the finished dimension thickness.

OKUBO JUNICHI (JP)
TAMURA KENJI (JP)
YOSHIDA KUNIHIRO (JP)
HWANG SAM SOO (JP)
NAKANO RYUSUKE (JP)
HORI MASAO (JP)
OTA YUKIHIRO (JP)

PCT/JP2019/001390

August 01, 2019

January 18, 2019

Click for automatic bibliography generation  

NIPPON STEEL CORP (JP)

B21K1/08; B21J5/02; F16C3/08

WO2016152933A1	2016-09-29
WO2018061765A1	2018-04-05
WO2019039193A1	2019-02-28

JPS5945051A	1984-03-13
JP2001105087A	2001-04-17

ASCEND IP LAW FIRM (JP)

View/Download PDF      PDF Help

Previous Patent: IMAGE PROCESSING DEVICE

Next Patent: METHOD FOR MANUFACTURING THIN FILM BATTERY ELEMENT