Patent attributes
In a fuel injection valve in which a funnel-shaped fuel collecting recess 35 is provided between a valve seat 8 and an outlet hole 7, and a flat fuel diffusion chamber 36 which diffuses a fuel radially outward and guides the fuel to a plurality of fuel injection holes 11 is provided between opposed surfaces of a valve seat member 3 and an injector plate 10, a seating portion 16a having a spherical band shape, and a valve tip end portion 16b which projects into a cone shape toward a center of the outlet hole 7 from the seating portion 16a and leaves its top portion in the outlet hole 7 even at the time of valve opening of a valve body 18 are formed at the valve body 18, a cone angle α of the valve tip end portion 16b is set to be larger than a funnel angle β of the fuel collecting recess 35, and an inner peripheral surface 7A of the outlet hole 7 is formed along an inner peripheral side curved surface of a virtual torus T so that the inner peripheral surface is connected to a bottom surface of the fuel collecting recess 35 and a ceiling surface of the fuel diffusion chamber 36. Thus, generation of eddies at the time of reverse of the fuel flow in the outlet hole of the valve seat member is prevented to reduce pressure loss of the fuel, thereby suppressing decrease in the amount of injected fuel, promoting atomization of the injected fuel and stabilizing spray forms.
