US Patent 10415527 Fuel injection valve

Recent exhaust gas regulation requires reduction of an amount and quantity of particulate matter included in an exhaust gas, and a normal maximum fuel pressure may be increased to approximately 35 MP. When the normal maximum fuel pressure is 35 MPa, a fuel injection valve is required to work for example at a pressure up to 45 MPa. In such a condition, a fluid force may exceed a valve opening force depending on a seat diameter, and a needle valve cannot be kept open and closed, when opening thereof is required.