| 摘要 |
PROBLEM TO BE SOLVED: To prevent any water from penetrating into a needle valve spring chamber from a sliding surface between the nozzle tip of an injection valve and a needle valve. SOLUTION: Initial injection fuel set up in the fuel passage 25 of an injection valve 2 in a range from a fuel sump part 20 up to a first ring groove 21, and injection water is set up in a range from the first ring groove 21 up to the underside position of a second ring groove 22 at the upstream side, and the latter half injection fuel is set up at the upstream side of this injection water, respectively in stratified form in this order. Each fuel is penetrated into a clearance on a sliding surface between a nozzle tip 12 and a needle valve 14 from each side of the fuel sump part 20 and the second ring groove 22, sealing up any water leaking in a clearance on a sliding surface between the nozzle tip 12 and the needle valve 14 from the first ring groove 21. According this method, such a possibility that water might be penetrated into the needle valve spring chamber 15 is thus prevented from occurring. |
