| 摘要 |
PURPOSE:To improve productivity and perform die casting at a low cost by forming an interval between mutually opposing faces on the inner wall of a cylinder head mounting frame and the outer wall of a cylinder respectively in a draft, and forming the inner end faces of a bridge and a water jacket in inclined faces. CONSTITUTION:An interval l between mutually opposing faces on the inner wall 1a of a cylinder head mounting frame 1 and the outer wall 2a of a cylinder 2 respectively is composed of a narrow interval l' and a wide interval l'', subsequent thereto while the interval l' being rendered a draft and stepped parts 1', 2' being provided on the boundary therebetween, so that a sacrifice core 6 can be recovered without touching the opposing faces 1b, 2b. The inner end faces of a bridge 5 and a water jacket 4 are formed to be inclined faces 5a, 1c symmetrical to each other for enabling the sacrifice core 6 to be removed therethrough. It is therefore possible to reinforce a cylinder 2 and prevent oscillations thereof by means of the bridge 5, to perform die casting with the repeatedly usable sacrifice core 6, thereby to improve productivity and carry out casting at a low cost. |
