OIL PASSAGE STRUCTURE IN POWER UNIT

PROBLEM TO BE SOLVED: To improve pump efficiency by returning excessive oil from an oil pressure control device to an oil pump side and miniaturize a crank case by shortening and simplifying the oil passage in a power unit including an internal combustion engine and a transmission built in the internal combustion engine, and having the oil pressure control device controlling the pressure of oil discharged from an oil pump disposed on the internal combustion engine in such a manner that it is disposed at an upper part of the crankcase in a side surface view disposed on the internal combustion engine. SOLUTION: An oil supply passage 207 leading oil discharged from the oil pump 100 is connected to the oil pressure control device 208 disposed at an upper part of the crankcase 36 from a lower side, one end of an excessive oil passage 209 leading excessive oil discharged from the oil pressure control device 208 is connected to the oil pressure control device 208 from a lower side, and the other end of the excessive oil passage 209 is connected to a suction side of the oil pump 100 in a range of an outer shape of a pump case 101 of the oil pump 100. COPYRIGHT: (C)2010,JPO&INPIT