Swirl-chamber Diesel engine with swirl chamber having depression for collecting fuel droplets

In a Diesel engine:

• means defining a cylinder;
• a piston reciprocally disposed in said cylinder to define a variable volume main combustion chamber;
• means defining a fixed volume swirl chamber and a passage from said swirl chamber to said main combustion chamber;
• a fuel injector disposed so as to project into said swirl chamber for injecting fuel thereinto;
• a glow plug disposed in close proximity of said injector and arranged to project into the injection path of said injector;
• means for defining a depression in said swirl chamber opposite said injector and adjacent said passage, for collecting any fuel not entrained in the air which swirls in said swirl chamber when said engine operates at relatively low engine speeds;
• means for defining a rounded lip between said depression and said passage, said lip extending into said swirl chamber, for retaining any fuel collected therein and preventing same from draining into said main combustion chamber;
• and
• means for sucking said collected fuel out of said depression when a flame passes through said passage, said sucking means comprising said lip defining means, said depression and said passage.

A method of operating a Diesel engine at relatively low engine speeds, comprising the steps of:

• swirling air in a swirl chamber;
• injecting fuel into said swirling air via a fuel injector;
• collecting any fuel not entrained in said swirling air in a depression disposed in said swirl chamber opposite said injector and adjacent a passage leading from said swirl chamber to a main variable volume combustion chamber;
• retaining the fuel collected in said depression by providing a rounded lip between said depression and said passage extending into said swirl chamber;
• heating and igniting the fuel entrained in said swirling air via a glow plug disposed adjacent to said injector which projects into the injection path of said injector;
• passing a flame past said lip and through said passage to said main combustion chamber;
• and
• sucking any fuel collected in said depression out of said depression using said flame.

In a Diesel engine:

• means defining a cylinder;
• a piston reciprocatively disposed in said cylinder to define a variable volume main combustion chamber;
• means defining a fixed volume swirl chamber and a passage leading from said swirl chamber to said main combustion chamber;
• a fuel injector disposed in said swirl chamber for injecting fuel into said swirl chamber in a direction substantially concurrent with the air which swirls therein;
• means defining a depression in said swirl chamber substantially opposite said fuel injector in the form of a depressed wall section, said wall section connects smoothly into the wall defining said swirl chamber, said wall section is depressed away from the path along which the air which swirls in said swirl chamber flows so that any fuel droplets which are not entrained in the air which swirls in said swirl chamber collect in said depression and are not drawn thereoutof by said swirling air;
• means defining a smooth rounded lip between said depression and said passage, said lip extending into said swirl chamber which prevents any fuel collected in said depression from draining into said passage;
• and
• means for drawing any fuel collected in said depression thereoutof when the combustion gases generated in said swirl chamber flow therefrom through said passage into said main combustion chamber, said drawing means comprising said lip defining means and said passage.