| 摘要 |
PURPOSE:To reduce the weight and to improve the strength by forming a recess between the water jacket and journal wall in the sideface of cylinder block while projecting rib chips from the sideface of cylinder block at the opposite sides of said recess. CONSTITUTION:The cylinder block B is constituted with cylinder section 1 and crank case section 2 respectively at the upper and lower half section. A water jacket 6 is formed while surrounding respective cylinder bore at the cylinder section 1 while plural journal walls 7 are formed along the arranging direction of cylinder bore at the crank case section 2. Here, a recess 8 is formed between the water jacket 6 and the journal wall 7 in the sideface of cylinder block B along the direction of crank shaft or the arranging direction of cylinder bore 3. While rib chips 9 are projected from the sideface of cylinder block B to the outside at the opposite sides of said recess 8. |
