| 摘要 |
<p>The invention provides a crankcase structure for an internal combustion engine, the crankcase structure can inhibit change of oil level, inhibit increase of friction of a crankshaft and a speed changer, and prevent cavitation generation of an oil pump. The crankcase structure for an internal combustion engine is provided with an oil bottom housing (2p) at a lower part of the crankcase (2), wherein, lower side separating walls (61L, 61R, 62L, 62R) in an upper and lower separation at a lower part of the oil level (S) of oil stored in the oil bottom housing (2p) in a proper amount when the internal combustion engine stops are formed by extending from case outside circumferential walls (2Ls, 2Rs) to case inner space, at an upper part in specified spacing with the lower side separating walls,upper-lower separated upper side separating walls (65L, 65R, 66L, 66R) of at least one party of the crankshaft or the speed changer are formed by extending from the case outside circumferential walls(2Ls, 2Rs) to the case inner space.</p> |
