| 摘要 |
PURPOSE:To reduce deformation due to heat by wrapping through casting a ferrous auxiliary frame in a part, into which a plain bearing is inserted under pressure, of a crank shaft and the like. CONSTITUTION:An auxiliary cast iron frame 8 is wrapped through casting in a part, into which a plain bearing 2 is inserted under pressure, of a crank case 1 to form a bearing hole 8a into which the plain bearing 2 is inserted under pressure. When an engine is put in warming up operation and the crank case 1 is expanded, since coefficient of thermal expansion of the ferrous auxiliary frame 8 is small, the inside diameter of the bearing hole 8a is hot largely changed. Further, though said frame 8 is drawn outward when the crank case 1 is expanded, said inside diameter is not largely changed because the frame 8 is made of cast iron and has high rigidity. |
