Fuel injection device nozzle plate

A nozzle plate to be attached to a front end of a valve body, the valve body having a fuel injection port, said nozzle plate comprising:

• a bottom wall part facing the fuel injection port and having a nozzle hole through which fuel injected from the fuel injection port is to pass, the bottom wall part being formed separate from the valve body and being configured to inject fuel from the fuel injection port through the nozzle hole into an intake air pipe, a first surface of the bottom wall part facing the fuel injection port to abut against a front end surface of the valve body, the first surface being defined as an inner plane and a second surface of the bottom wall part opposite to the first surface being defined as an outer plane, the inner plane and the outer plane defining front and rear surfaces of the bottom wall part, respectively, the second surface of the bottom wall part being perpendicular to a central axis of the nozzle plate;
• a cylindrical wall part extending from the inner plane of the bottom wall part in a direction along the central axis of the nozzle plate so as to fit onto an outer periphery of the front end of the valve body;
• a plurality of blades formed in an area of the outer plane of the bottom wall part so as to surround the nozzle hole, the bottom wall part, the cylindrical wall part, and the blades being integrally formed to have a monolithic one-piece construction, the blades protruding from the second surface of the bottom wall part along the central axis of the nozzle plate;
• wherein the bottom wall part and the blades are configured such that, when the fuel is injected from the nozzle hole and a pressure in the vicinity of the nozzle hole is reduced, the plurality of blades guide a flow of air from a radially outward side of the bottom wall part to a radially inward side of the bottom wall part to generate a swirling flow of the air about a center of the bottom wall part;
• and
• wherein the bottom wall part and the blades are configured such that the swirling flow of the air about the center of the bottom wall part changes to a helical flow by receiving kinetic momentum from fine particles of the fuel injected from the nozzle hole and the helical flow of the air transports the fine particles of the fuel.