| 摘要 |
PURPOSE:To improve the combustion performance of engine by providing main nozzle hole having wide path area and a grooved nozzle hole having narrow path area at the nozzle hole communicating between main and sub combustion chambers. CONSTITUTION:A nozzle hole 12 communicating between main and sub- combustion chambers 10, 3 is provided in a cylinder head 1. Main nozzle hole 17 having wide path area and a grooved nozzle hole 18 having narrow path area are provided in the nozzle hole 12. the grooved nozzle hole 18 is positioned in the circumferential direction R of piston against the main nozzle hole 17. In the final stage of compression stroke, an air flow S3 different from that S2 through main nozzle hole 17 is formed through the grooved nozzle hole 18. Since the gas flow will flow out from sub-combustion chamber 3 to main combustion chamber 10 in expansion stroke, the entire air in main combustion chamber 10 can be utilized effectively for combustion of gas, resulting in improvement of the combustion performance of engine. |
