Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
METHOD FOR MANUFACTURING FORGED CRANKSHAFT
Document Type and Number:
WIPO Patent Application WO/2019/146511
Kind Code:
A1
Abstract:
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.

Inventors:
OKUBO, Junichi (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
TAMURA, Kenji (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
YOSHIDA, Kunihiro (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
HWANG, Sam Soo (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
NAKANO, Ryusuke (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
HORI, Masao (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
OTA, Yukihiro (6-1 Marunouchi 2-chome, Chiyoda-k, Tokyo 71, 〒1008071, JP)
Application Number:
JP2019/001390
Publication Date:
August 01, 2019
Filing Date:
January 18, 2019
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
NIPPON STEEL CORPORATION (6-1 Marunouchi 2-chome, Chiyoda-ku Tokyo, 71, 〒1008071, JP)
International Classes:
B21K1/08; B21J5/02; F16C3/08
Attorney, Agent or Firm:
ASCEND IP LAW FIRM (5-17, Dojima 1-chome Kita-ku, Osaka-sh, Osaka 03, 〒5300003, JP)
Download PDF: