JPS6427739A - Method for casting crank case in multiple cylinder engine - Google Patents

Abstract

PURPOSE:To simplify core setting work and to reduce casting cost by forming a core setting in a mold forming barrel part in a crank case to the common unified member to the whole cylinders. CONSTITUTION:In the mold 30 for the crank case, the barrel part core 32 formed as the common unified member to the whole cylinders, for this example, four cylinders, is inserted. In the core 32, total five spaces 34 are arranged at both end parts and intermediate part and these form five bearing parts 12 in the four cylinder engine after casting. As the core 32 is formed as integrated body, in the barrel part in the crank case 10 produced as the product, the conventional partitioned wall does not exist and cut-out part or space 26 opening downward is formed between the bearing part 12 and skirt part 16. Further, as recessed parts 36 are arranged at upper and lower side edge parts in the core 32, ribs 28 toward vertical direction projected to axial line of cylinder bore 20 are formed at skirt parts 16 after casting.