Patent ID: 8225774
Filing Date: 2012-07-24
Classification: F01M,F16C

Abstract:
1. A lubrication system for a four stroke engine, comprising: an oil pan for storing lubrication oil; a crankcase, wherein a crankshaft is disposed, which crankshaft has a balance weight and is coupled with a piston of a cylinder; a gear assembly room; a rocker-arm chamber; and a gas-oil separator for separating gas and oil from a mix of gas and oil; wherein the oil pan communicates with the crankcase by an oil suction passage, in which a first check valve is disposed; the crankcase communicates with the gear assembly room by a first oil delivery passage; the gear assembly room communicates with the rocker-arm chamber by a second oil delivery passage, and the gear assembly room communicates with the oil pan by a third oil delivery passage; the rocker-arm chamber communicates with the crankcase by a first oil return passage, in which a second check valve is disposed.