| 摘要 |
PURPOSE:To reduce the frictional loss between a piston ring and a cylinder when a piston is near the top dead center, by providing an oil passage in the piston to coat the surface of the cylinder with oil from the passage to preponderantly supply the oil to the upper part of the cylinder. CONSTITUTION:An oil passage 8 is provided in a piston pin 7. Oil is conducted to an oil ring 9 through an oil passage 10 provided in a piston 6. Only when the piston 6 is near the top dead center, an oil passage 4 connects an oil passage 2 to another oil passage 5 provided in a connecting rod 3. At that time, the oil flows to the oil ring 9. Excess oil is conducted to the inside of the piston 6 through oil holes provided in the oil ring 9 and then returns to an oil pan. |
