| 摘要 |
PURPOSE:To form a crankshaft in light weight and in a small size, by integrally forming cylindrical parts, which should be a crank pin or a journal, with crank arms and tightening these arms by cylindrical core units. CONSTITUTION:Crank arms 16, 18 are integrally formed respectively with journal parts 12, 14, and these crank arms 16, 18 and a crank arm 20 positioned in their center are connected by crank pins 22, 24. The crank pins 22, 24, under the condition such that cylindrical parts 30, 32, 34, 36 integrally formed with the respective crank arms 16, 18, 20 are butted interposing spacers 38, 40 by each end face of these cylindrical parts, are tightened to be formed by core units 42, 44. Then the core unit 42 is welded to the internal surface part of small contour holes 46 formed in the crank arms 16, 20. |
