Patent ID: 8387900
Filing Date: 2013-03-05
Classification: F02D,F02M

Abstract:
1. A fuel injector comprising: (a) an injector housing having a top, a bottom and a body therebetween, said body having a cylindrical chamber therein and a hemispherically-shaped inner nozzle surface, said cylindrical chamber having a sealing seat, said bottom having an outlet nozzle formed therein and extending from said cylindrical chamber to the outside of said bottom, said outlet nozzle providing egress from said cylindrical chamber; (b) an inlet nozzle attached to said body and providing ingress into said cylindrical chamber; (c) a flow control member seated within said cylindrical chamber to control flow through said outlet nozzle in conjunction with said sealing seat, said flow control member having a hemispherical nose portion having a first radius of curvature and said hemispherically-shaped inner nozzle surface having a second radius of curvature; (d) a seal circumscribing said flow control member creating a pressure seal while still allowing said flow control member to move linearly within said cylindrical chamber; (e) a piezoelectric stack joined to a top of said flow control member such that the motion of said flow control member is driven directly by said piezoelectric stack as said piezoelectric stack expands or contracts to move said flow control member away from or toward said sealing seat and said outlet nozzle; and (f) a control system having a user interface and drive electronics connected to said piezoelectric stack for driving said flow control member to one or more open positions via expansion and contraction of said piezoelectric stack according to the level of applied current and voltage.