PURPOSE: To lighten a hollow chilled cam shaft and to improve wear resistance of a cam part by inserting a hollow shaft formed unitedly a bearing part, cam part and journal part with a lost foam pattern casting method as cast-in and chilling peripheral surface of the cam with chillers.
CONSTITUTION: Center cores 12, 13 are inserted into both end holes 10, 11 in the hollow shaft and set between a fixed metallic mold 14 and a movable metallic mold 15 in a lost foam pattern forming machine. Into a front end face bearing recessed part 18, cam recessed part 19, journal part recessed part 20, rear end face bearing recessed part 21 and bearing recessed part 22 in a carving recessed part 16, foaming styrene granular bodies are injected and filled. By jetting heated steam into the engraved recessed part 16, the lost foam pattern 29 composed of a front end face bearing part pattern 24, caM part pattern 25, journal part pattern 26, rear end face bearing part pattern 27 and bearing part pattern 28, is formed around the hollow shaft 1. The lost foam pattern 29 is held with the chillers and set in a casting device, and after pouring molten metal, the whole cam peripheral surface is chilled.
KUDOU TOMONAO
SAKASHITA TOSHIO
ASANO ISAO
