Patent ID: 7373913
Filing Date: 2008-05-20
Classification: F01M

Abstract:
1. A small internal combustion engine comprising: a crankcase; a crankshaft rotatably mounted in an interior of the crankcase by crankshaft bearings; a first oil passage disposed below the crankshaft bearings to extend substantially in parallel with the crankshaft, the first oil passage being configured to feed lubricating oil to the crankshaft bearings; a second oil passage disposed at a location higher than the first oil passage to extend substantially in parallel with the first oil passage, the second oil passage being configured to feed the lubricating oil to a component other than the crankshaft bearings; a third oil passage extending substantially in parallel with the first oil passage and the second oil passage, the third oil passage being configured to feed the lubricating oil to a component other than the crankshaft bearings; and a cross oil passage configured to extend so as to cross the first oil passage, the second oil passage, and the third oil passage; wherein the first oil passage, the second oil passage, and the third oil passage fluidically communicate with each other through the cross oil passage.