Internal-combustion engines – Charge forming device – Fuel injection system
Reexamination Certificate
1999-06-07
2001-05-08
Yuen, Henry C. (Department: 3747)
Internal-combustion engines
Charge forming device
Fuel injection system
C123S541000
Reexamination Certificate
active
06227173
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to liquefied petroleum gas fuel injection systems and more particularly to fuel line arrangements and cooling methods for such systems.
BACKGROUND OF THE INVENTION
Liquefied petroleum gas (“LPG”) fuel supply systems are known, for example as shown in applicant's U.S. Pat. Nos. 5,291,869; 5,325,838; and 5,423,303. Such systems typically include a number of specialized fuel injectors which receive fuel from a high pressure tank. A fuel rail connected in line with a series of injectors is often employed to deliver fuel to the injectors. In many systems, uninjected fuel is returned to the fuel tank. This is generally done to keep the supply fuel as cool as possible, particularly where it is intended to inject LPG in liquid rather than gaseous form.
In LPG systems where uninjected fuel is returned to the fuel tank, separate supply and return fuel lines are employed in the art. More than one supply line and more than one return line are also often employed, with a separate supply and return line for each bank of fuel injectors.
There are many problems associated with having multiple supply and return lines in LPG systems. One is that the fuel in the supply line is exposed to heat from the engine and other sources, which causes undesirable vaporization. Another problem is that all of the lines must be very strong, typically having large wall thickness and requiring reinforcement, in order to withstand the very high pressures (sometimes over 300 psi) that can occur in LPG systems. Other problems involve safety and environmental concerns. Due to the large number of hose connections and the large amount of exposed fuel line, the possibility of fuel leaks is substantially increased.
What has been needed is a fuel line arrangement for LPG systems, and a method, that avoid these problems.
SUMMARY OF THE INVENTION
According to the present invention, a method of cooling supply fuel in an LPG system, and a fuel line arrangement for an LPG system, are provided.
In the method of the present invention, an LPG system having a plurality of fuel injectors, a fuel supply and a fuel return line, and a fuel tank, is provided. The supply and return lines are communicated with the tank, and the supply line is communicated with each of the fuel injectors. The supply line is positioned within the return line so that return fuel substantially surrounds the supply line. Under certain conditions, return fuel in the fuel return line is vaporized, thereby cooling supply fuel in the supply line.
In the apparatus, a fuel line arrangement for an LPG system includes a fuel supply line for connection between the fuel tank and a plurality of fuel injectors and a fuel return line for connection to the tank and for returning a portion of the supply fuel from the supply line to the tank. The supply line is positioned within the return line so that the return fuel substantially surrounds the supply line. A mechanism is provided for vaporizing LPG returning to the tank through the return line, thereby cooling supply fuel.
These and other advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto. However, for a better understanding of the invention and its advantages, reference should be made to the drawings which form a further part hereof, and to the accompanying descriptive matter in which there is illustrated and described a preferred embodiment of the invention.
REFERENCES:
patent: 1860063 (1932-05-01), Tobler
patent: 1966223 (1934-07-01), Sass
patent: 2244800 (1941-06-01), Pascale
patent: 2264914 (1941-12-01), L'Orange
patent: 2286658 (1942-06-01), Voit
patent: 2475635 (1949-07-01), Parsons
patent: 2886014 (1959-05-01), Konrad et al.
patent: 2965303 (1960-12-01), Jackson
patent: 2978797 (1961-04-01), Ekelund
patent: 3398895 (1968-08-01), Claffey
patent: 3450351 (1969-06-01), Messerschmidt
patent: 3451627 (1969-06-01), Barber
patent: 3612012 (1971-10-01), Dreisin
patent: 3945353 (1976-03-01), Dreisin
patent: 3958757 (1976-05-01), Happel et al.
patent: 4099496 (1978-07-01), Nagase et al.
patent: 4421087 (1983-12-01), Schuurman
patent: 4434765 (1984-03-01), Eshelman
patent: 4471909 (1984-09-01), Perr
patent: 4489700 (1984-12-01), van der Weide
patent: 4503826 (1985-03-01), Kessler et al.
patent: 4503831 (1985-03-01), Rijkeboer
patent: 4503832 (1985-03-01), Pefley et al.
patent: 4545345 (1985-10-01), Pagdin et al.
patent: 4570602 (1986-02-01), Atkins et al.
patent: 4676478 (1987-06-01), Kiuchi
patent: 4700891 (1987-10-01), Hans et al.
patent: 4704591 (1987-11-01), Hafner
patent: 4768492 (1988-09-01), Widmer et al.
patent: 4796924 (1989-01-01), Kosugi et al.
patent: 4886305 (1989-12-01), Martin
patent: 4901974 (1990-02-01), Cook et al.
patent: 4938036 (1990-07-01), Hodgkins et al.
patent: 4957085 (1990-09-01), Sverdlin
patent: 4978148 (1990-12-01), Kosugi et al.
patent: 4984549 (1991-01-01), Mesenich
patent: 5027871 (1991-07-01), Guenther
patent: 5033444 (1991-07-01), Kaufman et al.
patent: 5044339 (1991-09-01), Hafner
patent: 5046702 (1991-09-01), Miyazawa et al.
patent: 5050840 (1991-09-01), Kondo et al.
patent: 5076242 (1991-12-01), Parker
patent: 5076244 (1991-12-01), Donaldson
patent: 5085402 (1992-02-01), O'Dell
patent: 5136986 (1992-08-01), Jensen
patent: 5156134 (1992-10-01), Tochizawa
patent: 5174262 (1992-12-01), Staerzl
patent: 5183209 (1993-02-01), Ricco et al.
patent: 5197436 (1993-03-01), Ozawa
patent: 5233963 (1993-08-01), Gregorius et al.
patent: 5237981 (1993-08-01), Polletta et al.
patent: 5251603 (1993-10-01), Watanabe et al.
patent: 5259651 (1993-11-01), Sharp
patent: 5291869 (1994-03-01), Bennett
patent: 5299605 (1994-04-01), Bergamini et al.
patent: 5325838 (1994-07-01), Bennett
patent: 5348847 (1994-09-01), Chasteen et al.
patent: 5355846 (1994-10-01), Ozawa
patent: 5377645 (1995-01-01), Moore
patent: 5423303 (1995-06-01), Bennett
patent: 5441234 (1995-08-01), White et al.
patent: 5449203 (1995-09-01), Sharp
patent: 5449204 (1995-09-01), Greene et al.
patent: 5479906 (1996-01-01), Collie
patent: 5533486 (1996-07-01), Qutub
patent: 5547231 (1996-08-01), Sharp
patent: 5566712 (1996-10-01), White et al.
patent: 5595160 (1997-01-01), Matsumoto et al.
patent: 5624140 (1997-04-01), Allen et al.
patent: 5735342 (1998-04-01), Nitta
patent: 4224908 A1 (1993-02-01), None
patent: 2 246988 (1992-02-01), None
patent: WO 81/00282 (1981-02-01), None
patent: WO 92/08888 (1992-05-01), None
patent: WO 92/08886 (1992-05-01), None
“Gasoline Fuel Injector” SAE J1832 NOV89, Report of the Fuel Injection Subcommittee, approved Nov. 1989, pp. 24.163-24.187.
Bi-Phase Technologies, L.L.C.
Gimie Mahmoud M
Merchant & Gould P.C.
Yuen Henry C.
LandOfFree
Fuel line arrangement for LPG system, and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fuel line arrangement for LPG system, and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuel line arrangement for LPG system, and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2470946