Fuel injector for internal-combustion engine

摘要

The fuel injector according to the invention comprises a needle valve 5 which slides inside a body counter to an elastic return device comprising two springs in series, defining two parts in the needle lift stroke, and a seat 6 through which the injection ports 4 open. In the first part of its lift stroke, the needle 5 moves away from the seat 6 by an amount such that the area of the imaginary cylinder M extending the port 4 between its rim R of intersection with the seat 6 and the needle 5 is less than the cross section of the hole 4. <IMAGE>