Patent attributes
A gaseous fuel injection valve includes: a valve housing; a metallic nozzle member having a flat valve seat and a nozzle bore passing through a central portion of the valve seat; a valve body provided at one end face with a rubber seating member which is operated in cooperation with the valve seat; a coil; and a return spring for urging a stationary core and the valve body toward the valve seat. The stationary core attracts the valve body to move the seating member away from the valve seat, when the coil is excited. In this injection valve, a fluorine resin valve seat coating is formed on the valve seat so that the seating member is brought into close contact with the valve seat coating. Thus, an oil-repellent property of the valve seat coating is provided to the valve seat to prevent adherence of oil to the valve seat, leading to an improvement in valve-opening response of the valve body upon the excitation of the coil.
