Patent Number: 6,305,342

Title: Lubrication system for internal combustion engine

Abstract: Looking from a front toward a rear of a vehicle, a crankcase has a crosssectional shape which gets narrower towards its bottom. The crankcaseincludes a crankshaft which extends parallel to a direction of travel forthe vehicle. A main shaft, a counter shaft and an output shaft of atransmission are arranged in a transmission chamber on one side of thecrankshaft. An oil tank is provided on the same side of the crankshaft andoutwardly of the transmission chamber. The oil tank is separated from thetransmission chamber by a partitioning wall. The oil tank has asubstantially crescent shape, with the lower end extending beneath theoutput shaft. An intake port of a feed pump is provided in the lowest partof the oil tank. An oil inlet for adding oil to the oil tank is providedjust above the oil tank. An overflow hole to the transmission chamber isprovided in the partitioning wall. The feed pump is provided on anopposite side of the crankshaft inside the crankcase. A scavenge pump,which sucks from an oil sump at the lowest section of the crankcase andreturns oil to the oil tank, is also provided on the opposite side of theis crankshaft and inside the crankcase. A drain hole communicates with theoil tank and with the transmission chamber. The drain hole is provided ina lower part of the crankcase and is closed by a drain bolt.

Inventors: Narita; Satoru (Saitama, JP), Shichinohe; Takashi (Saitama, JP)


International Classification:

Expiration Date: 10/23/2013