Cummins Engine Company, Inc.

Chad L Buchanan

Lester L Peters

Julius P Perr

John T Carroll, Iii

Bradlee J Stroia

Benjamin M Yen

A S Ghuman

Kevin L Vogt

David E Schisler

Dennis M Ashwill

James E Denton

Robert Samuel

A swirl tip injector nozzle housing is provided for a fuel injector which includes a fuel atomization enhancing feature for creating effective fuel atomization and breakup during discharge from the injector. The fuel atomization enhancing feature includes a plurality of curvilinear spray holes having an angle of curvature equal to approximately 90 degrees. Fuel flowing from the inlet of each spray hole to the outlet is induced, by the 90 degree angle of curvature, to flow through a tangential flow path or swirl within the spray hole causing rapid spreading and breakup of the fuel jet spray upon exiting the outlet of the spray hole. The fuel atomization enhancing feature may also include positioning each spray hole so as to extend orthogonally from the interior surface of the fuel cavity to create optimal entry of the fuel into the tangential flow path.

Swirl tip injector nozzle

An injection rate shaping nozzle assembly for a fuel injector is provided which includes a closed nozzle valve element and a rate shaping control device including an injection spill circuit for spilling a portion of the fuel to be injected to produce a predetermined time varying change in the flow rate of fuel injected into a combustion chamber. The spill circuit includes a spill passage integrally formed in the nozzle valve element. The rate shaping control device may include a spill accelerating chamber in formed in the nozzle valve element for creating a rapid increase in the spill flow rate. A spill circuit purge device is provided to remove fuel from the spill circuit and accelerating chamber between each of the injection events thereby ensuring an unimpeded, effective spill fuel flow during the next spill event. The purge device includes a purge passage formed of a predetermined size for restricting the flow of purge gas to ensure sufficient fuel removal from the injection spill circuit while avoiding excessive purge gas flow. The purge passage may include an annular clearance gap formed between the nozzle valve element and the nozzle housing wall, or alternatively, may include an orifice passage formed in the inner portion of the nozzle valve element. An improved method for forming a nozzle valve element having an axial center passage is also disclosed.

Injection rate shaping nozzle assembly for a fuel injector

Growing community of inventors

Westport, IN, United States of America

Chad L Buchanan