Internal-combustion engines – Charge forming device – Auxiliary air or gas used to inject fuel
Patent
1986-03-24
1989-06-27
Miller, Carl Stuart
Internal-combustion engines
Charge forming device
Auxiliary air or gas used to inject fuel
123531, 123585, F02M 3900
Patent
active
048419427
DESCRIPTION:
BRIEF SUMMARY
This invention relates to the metering of fuel to an engine particularly in applications where the fuel is injected directly into the combustion area of an engine.
There has previously been proposed methods of metering fuel wherein the metered quantity of fuel is displaced from a variable capacity chamber by a charge of gas, such as air, at an appropriate pressure. It is considered that the charge of gas contributes significantly to the efficient combustion of the fuel, at least in part because of improved atomization of the fuel.
It is the object of the present invention to provide a method and apparatus for delivering a metered quantity of fuel by a charge of gas which is effective and accurate in operation, convenient to manufacture and maintain, and assists in promoting a high degree of atomization of the fuel.
With these objects in view there is provided a method of metering fuel to an engine comprising supplying fuel and gas at respective pressures simultaneously to a chamber, cyclically communicating said chamber with the engine to deliver the fuel from the chamber to the engine by a flow of gas from the chamber, and regulating the pressure difference between the fuel and gas supplies to the chamber in accordance to engine load to control the quantity of fuel delivered to engine per cycle.
More specifically there is provided a method of metering fuel to an engine comprising providing continuously a supply of fuel under pressure to a closed fixed capacity chamber, periodically admitting gas to said chamber to maintain in the chamber a pressure not greater than the fuel pressure and opening a delivery port in said chamber for substantially the duration of the period of admission of gas to the chamber, whereby fuel in the chamber upon the admission of gas and fuel entering the chamber during the period of admission of gas is delivered from the delivery port.
Preferably the gas establishes a pressure in the chamber that is less than the fuel pressure so that fuel will continue to flow into the chamber while the gas pressure exists therein. Conveniently regulation of the quantity of fuel delivered is effected by varying the pressure difference between the chamber gas pressure and the fuel supply pressure and/or the duration of the period of admission of gas to the chamber.
As the difference between the fuel pressure and the gas pressure in the chamber during the fuel delivery period increases, the greater will be the amount of fuel which will flow into the chamber, and hence be discharged from the delivery port, for any selected period of admission of the gas to the chamber. Also while the admission of gas to the chamber is terminated, and the delivery port closed, fuel will continue to flow into the chamber until the pressure in the closed chamber equals the fuel supply pressure. Thus, between each period of admission of gas to the chamber a quantity of fuel will accumulate in the chamber. This quantity will increase as the difference between the fuel pressure and the gas pressure in the chamber at termination of the gas admission increases.
It will therefore be appreciated that by varying the above referred to pressure difference the quantity of fuel delivered during each period of opening of the delivery port may be regulated. The varying of the pressure difference may be achieved by varying the pressure of the fuel supply and/or the pressure of the gas supply. As normally the fuel is liquid, it is thus more convenient to regulate the fuel pressure and to maintain the gas pressure substantially constant.
The quantity of fuel delivered may of course also be varied by variation of the duration of admission of gas to the chamber while the delivery port is open, as fuel continues to flow into the chamber during this period.
Thus by varying the pressure difference above referred to, and/or the gas admission period in accordance with the fuel demand of the engine there is achieved a fuel metering system for a combustion engine. Preferably sudden variations of fuel demand may be accommodated by varying the l
REFERENCES:
patent: 4224904 (1980-09-01), Cleri
patent: 4387696 (1983-06-01), Yogo
patent: 4429674 (1984-02-01), Lubbing
patent: 4465050 (1984-08-01), Igashira
patent: 4519356 (1985-05-01), Sarich
patent: 4543939 (1985-10-01), Ehrhart
patent: 4561405 (1985-12-01), Simons
patent: 4676216 (1987-06-01), Ohsawa
Miller Carl Stuart
Orbital Engine Company Proprietary Limited
LandOfFree
Method and apparatus for metering fuel does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for metering fuel, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for metering fuel will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-805242