ELECTRTOMAGNETIC FUEL INJECTION VALVE

PURPOSE:To enhance the responsiveness of the opening/closing operation of an injection valve so as to improve the accuracy of fuel injection quantity by forming, with a non-magnetic material, at least either member of a stopper and a valve seat for restricting the stroke of movable elements. CONSTITUTION:A valve guide 9 including a valve seat 9a and a stopper 11 are formed with a titanium alloy which is a non-magnetic material. In this way, the formation with the non-magnetic material makes it possible to form a magnetic circuit with a normal yoke 3, a fixed core 4 and a plunger 5, and to extremely reduce any magnetic leak of the stopper 11 and the valve guide 9. As a result, the magnetism attracting and returning operation of movable elements 5-7 speeds up so as to shorten a period required for the rising and stopping operation of fuel injection, thereby remarkably enhancing fuel injection quantity performance. In addition, the adhesion of iron impurity to the stopper 11 and the valve seat 9a during fuel injection is prevented, thereby improving the accuracy of fuel injection quantity.