Fuel supply system

Claim 2

In a fuel-supply system for an engine, the combination of an air supply, a fuel supply, a mixing chamber for supplying a mixture of air and fuel to the engine, a throttle valve in the chamber for controlling the supply of the air-fuel mixture to the engine, a main-metering system including main-metering valve means having a main-metering supply passage connecting the air and fuel supplies to the mixing chamber, a main-metering orifice in the supply passage, a main-metering valve element maneuverable between open and closed settings for varying the effective size of the metering orifice and accordingly, the air-fuel mixture supplied to the mixing chamber, a venturi within the mixing chamber, the venturi having the exit thereof opening into the mixing chamber upstream from the throttle valve and at the narrowest section thereof and the entrance thereof communicating with the air supply, a discharge nozzle opening into the venturi entrance at the narrowest section of the venturi, restrictor valve means including a resistor valve element positioned between the main-metering valve element and the discharge nozzle for controlling flow therethrough, and motor means responsive to the pressure in the mixing chamber at a point just upstream from the throttle valve for operating the restrictor valve element so as to reduce flow to the discharge nozzle when the mixing chamber pressure approaches atmospheric pressure, and linkage means conneCting the throttle valve and the metering valve for movement together.

Claim 3

The fuel-supply system described in claim 1 wherein the metering valve element has a partial circular cross section provided with a tapered flat surface for varying the size of the orifice as the metering valve element is maneuvered.

Claim 4

In a fuel-supply system for an engine, the combination of an air supply, a fuel supply, a mixing chamber for supplying a mixture of air and fuel to the engine, a throttle valve in the chamber for controlling the supply of the air-fuel mixture to the engine, a main-metering system including main-metering valve means having a main-metering supply passage connecting the air and fuel supplies to the mixing chamber, a main-metering orifice in the supply passage, a main-metering valve element maneuverable between open and closed settings for varying the effective size of the metering orifice and accordingly, the air-fuel mixture supplied to the mixing chamber, a sealing member carried by the metering valve element for closing the orifice in the closed setting of the metering valve element, a venturi within the mixing chamber, the venturi having the exit thereof opening into the mixing chamber upstream from the throttle valve and at the narrowest section thereof and the entrance thereof communicating with the air supply, a discharge nozzle opening into the venturi entrance at the narrowest section of the venturi, and restrictor valve means including a restrictor valve element positioned between the metering orifice and the discharge nozzle for controlling flow therethrough, motor means responsive to the pressure in the mixing chamber at a point just upstream from the throttle valve for operating the restrictor valve element so as to reduce flow to the discharge nozzle when the mixing chamber pressure approaches atmospheric pressure, and linkage means connecting the throttle and the metering valve element for movement together.

Claim 5

In a fuel-supply system for an engine, the combination of an air supply, a fuel supply, a mixing chamber for supplying a mixture of air and fuel to the engine, a throttle valve in the chamber for controlling the supply of the air-fuel mixture to the engine, a main-metering system including main-metering valve means having a main-metering supply passage connecting the air and fuel supplies to the mixing chamber, a main-metering orifice in the supply passage, a main-metering valve element maneuverable between open and closed settings for varying the effective size of the metering orifice and accordingly, the air-fuel mixture supplied to the mixing chamber, a sealing member carried by the metering valve element for closing the orifice in the closed setting of the metering valve element, a venturi within the mixing chamber, the venturi having the exit thereof opening into the mixing chamber upstream from the throttle valve and at the narrowest section thereof and the entrance thereof communicating with the air supply, a discharge nozzle opening into the venturi entrance at the narrowest section of the venturi, and restrictor valve means including a restrictor valve element positioned between the metering orifice and the discharge nozzle for controlling flow therethrough, motor means responsive to the pressure in the mixing chamber at a point just upstream from the throttle valve for operating the restrictor valve element so as to reduce flow to the discharge nozzle when the mixing chamber pressure approaches atmospheric pressure, and linkage means connecting the throttle and the metering valve element for movement together.

Claim 6

In a fuel-supply system for an engine; the combination of an air supply; a fuel supply; a mixing chamber connected to the engine; a throttle valve in the chamber for controlling the supply of a air-fuel mixture to the engine; an idle-metering system including an idle-metering supply passage for connecting the air and fuel supplies to the mixing chamber downstream from the throttle valve, an idle-metering orifice within the passage, an idle-metering valve element adjustable to vary the effective size of the orifice and accordingly the air-fuel mixture supplied to the mixing chamber; a main-metering system including a venturi within the mixing chamber, the venturi having the exit thereof opening into the mixing chamber upstream from the throttle valve and at the narrowest section thereof and the entrance thereof communicating with the air supply, a discharge nozzle opening into the venturi at the narrowest section thereof, main-metering valve means including a main-metering supply passage connecting the discharge nozzle to both the air and fuel supplies, a main-metering orifice in the passage between the nozzle and the air and fuel supplies, a main-metering valve element maneuverable between open and closed settings for varying the effective size of the main metering orifice and accordingly the air-fuel mixture supplied to the nozzle, a sealing member carried by the metering valve element for closing the orifice in the closed setting of the main metering valve element, and restrictor valve means including a restrictor valve element positioned between the main metering orifice and the discharge nozzle for controlling the supply of the air-fuel mixture therethrough and motor means responsive to the pressure in the mixing chamber at a point just upstream from the throttle valve for operating the restrictor valve element so as to reduce the flow to the discharge nozzle as the pressure approaches atmospheric pressure, linkage means directly connecting the throttle valve and the main metering valve element for movement together; and enrichment valve means including an air supply passage connected to the air supply, an enriching supply passage connected both to the fuel supply and the air supply, an outlet connected to the mixing chamber at a point downstream from the throttle valve, an enrichment valve element for controlling the communication between the air and the enriching supply passages and the outlet, and a temperature-responsive motor operative when the ambient temperature pressure is below a predetermined value to actuate the enrichment valve element so as to connect the air and the enriching supply passages to the outlet and thereby cause both the motor engine idle speed to increase and the mixture to be enriched to prevent engine stall.

Claim 7

In a fuel-supply system for an engine; the combination of an air supply; a fuel supply; a mixing chamber connected to the engine; a throttle valve in the chamber for controlling the supply of a air-fuel mixture to the engine; an idle-metering system including an idle-metering supply passage for connecting the air and fuel supplies to the mixing chamber downstream from the throttle valve, an idle-metering orifice within the passage, an idle-metering valve element adjustable to vary the effective size of the orifice and accordingly the air-fuel mixture supplied to the mixing chamber; a main-metering system including a venturi within the mixing chamber, the venturi having the exit thereof opening into the mixing chamber upstream from the throttle valve and at the narrowest section thereof and the entrance thereof communicating with the air supply, a discharge nozzle opening into the venturi at the narrowest section thereof, main-metering valve means including a main-metering supply passage connecting the discharge nozzle to both the air and fuel supplies, a main-metering orifice in the passage between the nozzle and the air and fuel supplies, a main-metering valve element maneuverable between open and closed settings for varying the effective size of the main metering orifice and accordingly the air-fuel mixture supplied to the nozzle, a sealing member carried by the metering valve element for closing the orifice in the closed setting of the main metering valve element, and restrictor valve means including a restrictor valve element positioned between the main metering orifice and the discharge nozzle for controlling the supply of the air-fuel mixture therethrough and motor means responsive to the pressure in the mixing chamber at a point just upstream from the throttle valve for operating the restrictor valve element so as to reduce the flow to the discharge nozzle as the pressure approaches atmospheric pressure, linkage means directly connecting the throttle valve and the main metering valve element for movement together; and enrichment valve means including an air supply passage connected to the air supply, an enriching supply passage connected both to the fuel supply and the air supply, an outlet connected to the mixing chamber at a point downstream from the throttle valve, an enrichment valve element for controlling the communication between the air and the enriching supply passages and the outlet, and a temperature-responsive motor operative when the ambient temperature pressure is below a predetermined value to actuate the enrichment valve element so as to connect the air and the enriching supply passages to the outlet and thereby cause both the motor engine idle speed to increase and the mixture to be enriched to prevent engine stall.

Claim 8

A fuel-supply system as described in claim 4 further including accelerating pump means communicating with the fuel supply and operatively connected to the linkage means so as to provide additional fuel to the mixing chamber when the main-metering valve element is maneuvered to the open setting.