FUEL INJECTION VALVE

摘要

A fuel injection valve (1) comprises a valve seat (11) with a valve seat (11a) defining a conical space tapering-off toward an injection hole (11b), a needle (12) including a valve part (12b) having a curved surface abutting onto the valve seat (11a) and a columnar sliding part (12a) on the upstream side farther than the valve seat (11a), and a swirler (10) slidably holding the sliding part (12a). The amount of the fuel injected from the injection hole (11b) is controlled by opening and closing of the gap between the valve part (12b) and the valve seat (11a). Where the curvature radius of the valve part (12b) in the axial direction at its point contacting with the valve seat (11a) is R and the outer diameter of the sliding part (12a) is D, R>D/2.