Patent ID: 9127635
Filing Date: 2015-09-08
Classification: F02M

Abstract:
1. A method of generating a spray by a fluid injection valve comprising orifices, the method comprising: forming a relatively faster flow and a relatively slower flow in a corresponding orifice, wherein the faster flow is configured to press a fuel into an inner surface of the corresponding orifice, due to a faster speed and in response to an air entering the corresponding orifice between the faster flow and the inner surface of the corresponding orifice, wherein the fuel is spread forming a liquid film in each of the orifices, injecting the liquid film as individual jet flows from the orifices positioned on an orifice plate proximate one another along a curve, thereby forming a column underneath the orifices comprising adjacent individual jet flows at a circumference of the column and an internal air region surrounded by inner surfaces of the individual jet flows, as seen in a direction down from the orifices, wherein the injected liquid film travels a predetermined distance and starts to split, whereby atomized liquid drops are generated, inducing the Coanda effect by creating a difference between an internal air pressure in the internal air region and an external air pressure on an outside of outer surfaces of the individual jet flows; causing the adjacent individual jet flows injected from each of the orifices to start converging by the Coanda effect acting on the individual jet flows at a position of a break-up length; and allowing a convergence of the individual jet flows to continue until the Coanda effect disappears, thereby generating a spray from the individual jet flows at a downstream position farther than the position of the break-up length, wherein the forming the relatively faster flow and the relatively slower flow comprises: generating a back-flow by changing a travel direction of a portion of the fuel, after passing an inlet of the orifice, to an opposite direction by collision with a surface disposed beyond an inlet of the orifice, while allowing another portion of the fuel to travel in a same travel direction and flow directly into the inlet of the orifice, wherein the back-flow is generated with a reduced speed, thereby forming the relatively slower flow, and the another portion of the fuel attains a relatively greater speed due to the reduced speed of the portion of the fuel forming the back-flow.