| 摘要 |
PURPOSE:To balance the reciprocating mass with the difference in the diameter of each piston pin eliminated or minimized by making the first and second piston pin hollow while the third piston pin is made solid. CONSTITUTION:The reciprocating mass of the first and second piston and related components 131, 132 are made equal with each other, and the sum of the reciprocating masses of them are made equal to that of the third piston and related components 13. In order to satisfy those conditions, the first and second piston pins 151, 152 are made hollow while the third piston pin 153 is made solid. As the capacity of a cavity which is connected to the crank chamber is avoided from being excessively narrowed, cooling the inside of the third piston by the fuel-air mixture and lubrication oil is not obstructed. |
