Intermittent type swirl injection nozzle

Claim 1

An intermittent type swirl injection nozzle comprising: a nozzle body having a through hole formed therein, a spray hole formed at a leading end of said through hole and a body seat connected to said spray hole; a needle valve inserted into said through hole of said nozzle body slidably in the axial direction of said through hole, said needle valve having a needle seat at a ;eading end thereof for opening and closing said spray hole; a partition member of a cylindrical shape fittedly and fixedly inserted into said through hole of said nozzle body, and having tangential passage means formed on an outer wall thereof for imparting swirling movement of fuel when said needle valve is lifted to open the spray hole and to spray the fuel in a conical form through the spray hole; and a variable gap area formed between a portion of the outer periphery of said needle valve and a portion of an inner wall of said partition member, which portions confront each other in the direction parallel to the axial direction of said needle valve, said variable gap area being increased in accordance with the lift of said needle valve, said tangential passage means and said variable gap area commuicating, at their upstream side, with a fuel supply passage and, at their downstream side, with said spray hole, thereby controlling the fuel flow rate between said tangential passage means and said variable gap area in accordance with the lift of said needle valve so as to vary an injection rate and a spray angle.