Patent ID: 6092744
Filing Date: 2000-07-25
Classification: F02M

Abstract:
A fuel injector comprising:an injector body defining a fuel inlet fluidly connected to a low pressure space, a trapped volume and a fuel pressurization chamber in fluid communication with a nozzle outlet;a needle valve member positioned in said injector body and being movable between an inject position in which said fuel pressurization chamber is open to said nozzle outlet, and a closed position in which said nozzle outlet is blocked to said fuel pressurization chamber;said needle valve member including a lifting hydraulic surface exposed to fluid pressure in said fuel pressurization chamber, and a closing hydraulic surface exposed to fluid pressure in said trapped volume;at least one of said needle valve member and said injector body defining a pressure release passage extending between said trapped volume and said low pressure space; anda pressure regulating valve positioned in said pressure release passage, and having a regulating valve member movable to an open position when fluid pressure in said trapped volume is above a pop-off pressure.