Internal-combustion engines – Multiple piston – common nonrestrictive combustion chamber – Four-cycle
Patent
1991-04-01
1996-08-06
Dolinar, Andrew M.
Internal-combustion engines
Multiple piston, common nonrestrictive combustion chamber
Four-cycle
123 9012, F01L 124
Patent
active
055423825
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates generally to a compact internal combustion engine having dual compression and dual expansion and more particularly to an engine having multi-piston subassemblies preferably in back-to-back dynamically balanced units.
BACKGROUND ART
An internal combustion engine generally includes one or more reciprocating pistons operably connected to a crankshaft by a connecting rod to deliver energy therefrom. Such engines can operate on a 4-stroke cycle with sequentially timed phases of intake, compression, power, and exhaust, as well as 2-stroke-cycle. In a spark ignited engine a mixture of fuel and air is compressed by the piston within the closed confines of the cylinder. Near the end of the compression phase ignition occurs either by compression heating or by an ignition device to form hot burning gas which expands and drives the piston to create power.
In a diesel engine air is similarly compressed during the compression phase. Near the end of the compression phase, fuel is injected into the cylinder where it will mix with the compressed air and spontaneously ignite to form hot burning gas which, during the expansion phase of the cycle, expands against the movable piston and thereby creates power.
The last several years has seen an increasing emphasis on designing for improved fuel economy and efficiency, reduced emissions, a greater service life, and an increased power output per unit engine size.
The power of engines having similar combustion systems can be compared on the basis of their relative air flows. Conventionally there are two approaches to obtaining high air flow rates through a given engine volume. The first is the application of turbochargers to raise the density of the air entering the cylinders. The second is typified by the Wankel rotary piston engine in which a major geometric change achieves large "cylinders" in a small engine volume. The highest power density levels are achieved by combining these methods. The rotary piston engine is unsuited geometrically to withstand high cylinder pressures and to use high compression ratios so the fuel economy is poor and the potential for using turbochargers to boost the inlet air to high density is limited to levels below conventional engines.
Conventionally reciprocating engines use large bore/stroke ratio when optimized for power and a smaller bore/stroke ratio when optimized for economy. This stems from the importance of providing enough valve area for good breathing for power and a compact combustion chamber with high compression for economy. By using two stage compression and expansion processes it is possible to achieve induction in a large bore/stroke cylinder and combustion in a more compact space and so to achieve a better combination of high power and high efficiency.
It is well known that dilution of charge by recirculating exhaust gas can have a beneficial influence on flame temperature and the level of NO.sub.x emissions from an engine. Conventionally the exhaust gas subtracts from the space available for a fresh charge of air and so this method is inappropriate for high power levels.
Accordingly what is needed is an improved internal combustion engine which is (a) compact because it has large "cylinders" for induction relative to its volume, (b) efficient because it can use high compression ratios with a compact combustion space and, (c) low on NO.sub.x emissions because it achieves high levels of exhaust retention without loss of power.
Disclosure of the Invention
In one aspect of the present invention, a method of burning a mixture of combustible fuel and air in an engine includes a housing defining an operating chamber, a first piston assembly defining a bore is disposed in the operating chamber and defines therewith an intake chamber and an exhaust chamber. A second piston assembly is reciprocally disposed in the bore of the first piston assembly and defines therewith a combustion space. A crankshaft is rotatably supported in the housing and the second piston assembly is operatively connected t
REFERENCES:
patent: 651742 (1900-06-01), Anderson
patent: 1367797 (1921-02-01), Cage
patent: 1458771 (1923-06-01), Pagel
patent: 1539938 (1925-06-01), Franchimont et al.
patent: 1741947 (1929-12-01), Hutchinson
patent: 1771335 (1930-07-01), Karpes
patent: 1871589 (1932-08-01), Dainton
patent: 1882971 (1932-10-01), Schimanek
patent: 2027891 (1936-01-01), Weitzel
patent: 2255925 (1941-09-01), Heylandt
patent: 2280487 (1942-04-01), Heylandt
patent: 2910973 (1959-11-01), Witzky
patent: 2939441 (1960-06-01), Luttrell
patent: 3040721 (1962-06-01), Schotthoefer
patent: 3177853 (1965-04-01), Hendershot
patent: 3417738 (1968-12-01), Basiletti et al.
patent: 3630178 (1971-12-01), Erickson
patent: 3808818 (1974-05-01), Cataldo
patent: 3831565 (1974-08-01), Avery
patent: 3878821 (1975-04-01), White
patent: 4010675 (1977-03-01), Lassota
patent: 4090478 (1978-05-01), Trimble et al.
patent: 4157080 (1979-06-01), Hill
patent: 4218994 (1980-08-01), Reed
patent: 4325331 (1982-04-01), Erickson
patent: 4353331 (1982-10-01), Erickson
patent: 4367700 (1983-01-01), Pace
patent: 4437437 (1984-03-01), Erickson
patent: 4449488 (1984-05-01), Heaton
patent: 4641613 (1987-02-01), Delesalle
patent: 4671221 (1987-06-01), Geringer et al.
patent: 4759318 (1988-07-01), Adams
patent: 4913100 (1990-04-01), Eickmann
patent: 4917054 (1990-04-01), Schmitz
patent: 4958601 (1990-09-01), Lyons
patent: 5056471 (1991-10-01), Van Husen
patent: 5072589 (1991-12-01), Schmitz
patent: 5125371 (1992-06-01), Erickson et al.
patent: 5341774 (1994-08-01), Erickson
Caterpillar Inc.
Dolinar Andrew M.
Macy M.
Rhoads Kenneth A.
LandOfFree
Dual compression and dual expansion internal combustion engine a does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dual compression and dual expansion internal combustion engine a, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dual compression and dual expansion internal combustion engine a will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2184703