| 摘要 |
PURPOSE:To improve the combinative strength between a cam part made of ceramic and a shaft part made of light alloy, by mounting a core member, having stopper parts in both end parts and made of metal with a comparatively small thermal expansion coefficient, to be filled in the hollow part of the shaft part. CONSTITUTION:A core member 13 made of metal of iron or the like with a comparatively small thermal expansion coefficient is mounted to be filled in the hollow part of a shaft part 12. Even if a cam shaft is reheated when it is used, a thermal expansive amount in the whole shaft part 12 is limited by a thermal expansive amount of the core member 13 further thermal expansion of the shaft part 12 is restricted from both ends, consequently a compressive strain is generated in the inside of the shaft part 12, and a large compressive strain is generated in a penetrating part 12a through a cam part 11. Accordingly, a condition, that shoulder parts 16 of the shaft part 12 made of light alloy are firmly contacted under pressure with both end faces 15 of the cam part 11 made of ceramic, can be maintained, and large combinative strength can be ensured between both the cam part and the shaft part. |
