Patent ID: 7073730
Filing Date: 2006-07-11
Classification: F02M

Abstract:
1. A fuel injector for a fuel-injection system of an internal combustion engine, comprising: a valve-seat surface; a valve needle; a hydraulic coupler; a valve-closure member formed at the valve needle via the hydraulic coupler, the valve-closure member cooperating with the valve-seat surface to form a valve-sealing seat and the hydraulic coupler including a master piston and a slave piston that are connected to a pressure chamber; and an actuator that is one of piezoelectric and magnetostrictive, the actuator actuating the valve-closure member; wherein the hydraulic coupler includes a ball-check valve including a ball-sealing seat, a ball and a ball-valve spring, wherein the ball-valve spring simultaneously operates as a coupler-spring element for generating a prestressing force on the master piston counter to a working direction and on the slave piston in the working direction, wherein the ball-valve spring with its one end abuts against the master piston via a spring-pressure piece and on its other end is braced on the ball via a ball-pressure piece; wherein the pressure chamber is connected to a fuel-inflow in a flow-through direction of the pressure chamber via an inflow bore and the ball-check valve.