A LUBRICATING SYSTEM FOR A FREE ROTATION SMALL-SIZE FOUR-STROKE GASOLINE ENGINE

摘要

A lubricating system for a free rotation small-size four-stroke gasoline engine is provided in the application, it includes a crankcase(31), a crankshaft(32), a one-way valve(33) for introducing gas, a one-way valve(34) for exhausting gas, and an oil separator(35). The crankshaft(32) is mounted to the crankcase(31) by the bearings(36), a chamber(38) surrounding the crankshaft is provided at an end of the crankshaft(32), a channel(39) is provided in the crankshaft, one end of the channel(39) is communicated with the chamber(38), the other end of the channel is communicated with the crankcase, the oil separator(35) is communicated with a valvechamber(310) by the one-way valve(33) for introducing gas and is communicated with the chamber(38) surrounding the crankshaft by the one-way valve(34) for exhausting gas and finally is communicated with the crankcase, there is an air outlet(311) in the oil separator(35).