Abstract: A method and apparatus for injecting fluid into a machine are disclosed. A fluid injector is disclosed having a nozzle body with first and second body portions and at least one fluid injection orifice within the second body portion. The nozzle body may be configured for transmitting fluid from the first body portion toward the orifice. The fluid injector may also include a check member movably arranged inside the nozzle body for affecting fluid flow through the orifice and having a contoured outer surface defining (i) a recessed region and (ii) a generally convex region forming at least a portion of the recessed region.

Abstract: A method and apparatus for injecting fluid into a machine are disclosed. A fluid injector is disclosed having a nozzle body with at least one fluid injection orifice therein and being configured for transmitting fluid toward the injection orifice. The nozzle body may have a generally curved internal wall at an end portion of the nozzle body. A check member may be movably arranged inside the nozzle body for affecting fluid flow through the injection orifice. The check member may have (i) a recessed region on the surface of the check member and (ii) a generally curved region at an end portion of the check member. The check member may be movable to a flow blocking position in which (i) the check member engages the nozzle body to prevent fluid flow through the injection orifice, (ii) the recessed region is disposed proximate the injection orifice, and (iii) a chamber volume exists between the end portion of the nozzle body and the end portion of the check member.