| 摘要 |
PROBLEM TO BE SOLVED: To surely enable discharge of gas from a cavity for a nose portion of a high speed cam and cast a groove for a gap portion between the nose portion of the high speed cam and a nose portion of a low speed cam in a precise shape. SOLUTION: A chill block 36 forming cavities 33a and 34a casting nose portions 10a and 11a are provided with a nose cavity forming portion 40 for a high speed cam, two nose cavity forming portions 41 for a low speed cam, and two connecting portions 42 integrally connecting the nose cavity forming portion 40 for the high speed cam and two nose cavity forming portions 41 for the low speed cam and also forming a cavity for a part of a groove 12 for a gap. Gas in the cavity 33a for the nose portion of a high speed cam 10 is surely discharged so that an interlocked passage 43 communicating with a central axis 44 side and an opposite side against the central axis 44 is formed on the nose cavity forming portion 40 for the high speed cam. Further, a part between the nose portions 10a and 11a of the groove 12 for the gap is cast in a precise shape. |
