Title:
CHILLED CAST IRON HOLLOW CAMSHAFT AND CASTING METHOD THEREFOR
Document Type and Number:
Japanese Patent JP3185781
Kind Code:
B
Abstract:
PROBLEM TO BE SOLVED: To simultaneously realize weight reduction and high hardness by providing a double layer structure composed of a white iron structure having a highly hard cam surface and a graphite structure having a soft inner wall of a central hole.
SOLUTION: A chilled cast iron hollow camshaft for an automobile engine is formed as a double layer structure composed of a white iron structure 3 having the highly hard outer periphery of a cam part and a graphite structure 5 having a soft inner wall part of a hollow hole 4 by inclusion casting of a hollow core. The shaft end is formed so as to have a matrix softer than the graphite structure 5 and excellent in cutting performance. Thus, casting takes an annealing method of placing a heating core or a pad in an end part. Thus, the graphite structure 5 can be sufficiently exhibited by using the hollow core as a core. Graphitization of this part is promoted further by arranging the heating core in the end part, and a soft matrix further transformed into ferrite can be obtained.
Inventors:
Madono, Osamu
Application Number:
JP1999000073845
Publication Date:
May 11, 2001
Filing Date:
March 18, 1999
Export Citation:
Assignee:
Madono, Osamu
RIKEN KYASUTEKKU:KK
RIKEN KYASUTEKKU:KK
International Classes:
B22D15/00; F01L1/04; F16C13/00; F16H53/02; (IPC1-7): F16H53/02; B22D15/00; F01L1/04; F16C13/00