Rotor-type carburetor with improved fuel scavenging and atomization apparatus and methods

A rotor-type carburetor for use with an internal combustion engine, comprising:

• a body having an air flow passage extending therethrough along an axis;
• turbine rotor means carried by said body for rotation within said air flow passage about said axis in response to air flow through said air flow passage;
• passageway means, formed in said turbine rotor means, for centrifugally flowing a metered quantity of fuel from a source thereof through said turbine rotor means in response to rotation thereof;
• and
• discharge means for receiving the metered fuel from said turbine rotor means, during rotation thereof, and discharging it in the form of first and second series of differently sized, atomized fuel droplets for mixture with air traversing said air flow passage, the fuel droplets in said first series thereof having a predetermined size relationship with the droplets in said second series thereof,
• said discharge means including a spray ring carried by said turbine rotor means and having first means associated therewith for forming said first series of fuel droplets, and second means associated therewith for forming said second series of fuel droplets.

A rotor-type carburetor for use with an interior combustion engine having a fuel supply system adapted to supply fuel to said rotor-type carburetor, comprising:

• a body having an air flow passage extending therethrough along an axis;
• turbine rotor means carried by said body for rotation within said air flow passage about said axis in response to air flow through said air flow passage;
• passageway means, formed in said turbine rotor means, for centrifugally flowing a metered quantity of fuel from a source thereof through said turbine rotor means in response to rotation thereof,
• discharge means for receiving the metered fuel from said turbine rotor means, during rotation thereof, and discharging it in the form of first and second series of different sized, atomized fuel droplets for mixture with air traversing said air flow passage, the fuel droplets in said first series thereof having a predetermined size relationship with the droplets in said second series thereof;
• and
• fuel scavenging means for capturing fuel discharged from said discharge means during spin-down periods of said turbine rotor means to prevent the discharge fuel from being delivered to the engine, and for returning the captured fuel to the fuel delivery system, said fuel scavenging means including:
• capillary passage means, formed in the interior of said body, for receiving fuel discharged from said discharge means, and
• transfer means for transferring fuel received by said capillary passage means to the fuel supply system of the engine.

A rotor-type carburetor for use with an internal combustion engine, comprising:

• a body having an air flow passage extending therethrough along an axis;
• turbine rotor means carried by said body for rotation within said air flow passage in response to air flow therethrough;
• passageway means, formed in said turbine rotor means, for centrifugally flowing a metered quantity of fuel from a source thereof through said turbine rotor means in response to rotation thereof;
• and
• discharge means for discharging the metered fuel in the form of first and second series of differently sized, atomized fuel droplets for mixture with air traversing said air flow passage, the fuel droplets in said first series thereof having a predetermined size relationship with the fuel droplets in said second series thereof, and for automatically varying, in a predetermined manner, the ratio of the flow rate of the fuel droplets in said first series thereof to the flow rate of the fuel droplets in said second series thereof, said discharge means including a spray ring having a radially inner side surface, a radially inwardly bent axial end portion having a spray edge formed thereon, and at least one fuel discharge passage formed in said inner side surface and opening outwardly through an exterior surface of said spray ring, said spray ring being adapted to receive a flow of metered fuel along said inner side surface and simultaneously discharge the received fuel outwardly through said at least one fuel discharge passage and across said spray edge to respectively form said first and second series of fuel droplets.

A rotor-type carburetor for use with an internal combustion engine, comprising:

• a body having an air flow passage extending therethrough along an axis;
• turbine rotor means carried by said body for rotation within said air flow passage in response to air flow therethrough;
• passageway means, formed in said turbine rotor means, for centrifugally flowing a metered quantity of fuel from a source thereof through said turbine rotor means in response to rotation thereof;
• and
• discharge means for discharging the metered fuel in the form of first and second series of differently sized, atomized fuel droplets for mixture with air traversing said air flow passage, the fuel droplets in said first series thereof having a predetermined size relationship with the fuel droplets in said second series thereof, and for automatically varying, in a predetermined manner, the ratio of the flow rate of the fuel droplets in said first series thereof to the flow rate of the fuel droplets in said second series thereof,
• said fuel droplets in said first series thereof being larger than said fuel droplets in said second series thereof, and
• said flow rate ratio being varied by said discharge means in a manner such that during a first, relatively low speed range of the engine the magnitude of said ratio is greater than its magnitude during a second, relatively higher speed range of the engine.

A method of preventing fuel delivery to an engine from a roto-type carburetor during rotor spin-down periods thereof, the engine having a fuel delivery system adapted to deliver fuel to the carburetor, said method comprising the steps of:

• capturing fuel discharged from the carburetor during rotor spin-down periods thereof prior to the entry of the discharged fuel into the engine;
• and
• returning the captured fuel to the fuel delivery system,
• said capturing step being performed by forming capillary openings in the interior surface of the carburetor and receiving the discharged fuel in said capillary openings, and
• said returning step being performed by drawing the received fuel into the fuel supply system.