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US4253433A Expired / Lapsed US ⏱️ 0.0 years remaining

Stratified-charge two-stroke internal combustion engines

Assignee: Queen's University Belfast
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Filing: 1979-05-11
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Granted: 1981-03-03
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Expires: 1999-05-11
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Abstract

Abstract In a crankcase scavenged two-stroke internal combustion engine, a duct and at least one further passage extends between the crankcase chamber and the combustion chamber. There is a fuel/air mixture port leading into the duct and a pure air port leading into the duct or the crankcase chamber. The passage exits into the combustion chamber between the exit into that chamber from the duct and an exhaust port leading out of the combustion chamber. In operation fuel enters the combustion chamber in the air of the fuel/air stream entering the duct and air is additionally pushed into the combustion chamber by the downward movement of the piston through the passage and the duct. The fuel is separated from the exhaust port by a layer of air leading to better fuel consumption and higher oxidation combustion products.

Inventors

  • 👤 Gordon P. Blair

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 08:38
CPC Classifications
F; F02; F02B; F02B75/00; F02B75/16; F02B75/18; F02B75/20; F02B25/00; F02B25/14; F02B25/20; F02B25/22; F02B33/00; F02B33/02; F02B33/04; F02B33/44; F02B61/00; F02B61/02; F02B75/02; F02B2075/022; F02B2075/025; F02B2075/1804; F02B2075/1808; F02B61/04; F02B61/045; Y; Y10; Y10S; Y10S123/00; Y10S123/04

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 195 words
A stratified-charge two-stroke internal combustion engine comprising: a combustion chamber having an exhaust port, a first inlet port, and a second inlet port positioned closer to said exhaust port than said first inlet port; a piston reciprocable in said combustion chamber; a crankcase chamber; a first duct extending from the first inlet port in the combustion chamber to a position in the crankcase chamber remote from said combustion chamber; a first admission port connecting with said first duct at a position intermediate its ends for introducing a fuel-air mixture into said first duct; a second duct extending between the second inlet port in the combustion chamber and said crankcase chamber; and a second admission port communicating with said crankcase chamber for introducing air into said crankcase chamber, communication between said combustion chamber and said crankcase chamber through said first and said second ducts being controlled by movement of said piston, the arrangement of said first and second second inlet portions being such that air introduced into said combustion chamber through said second duct substantially separates a fuel-air mixture introduced into said combustion chamber through said first duct from gases being exhausted through said exhaust port.
Claim 2
Dependent Claim 195 words
A stratified-charge two-stroke internal combustion engine comprising: a combustion chamber having an exhaust port, a first inlet port, and a second inlet port positioned closer to said exhaust port than said first inlet port; a piston reciprocable in said combustion chamber; a crankcase chamber; a first duct extending from the first inlet port in the combustion chamber to a position in the crankcase chamber remote from said combustion chamber; a first admission port connecting with said first duct at a position intermediate its ends for introducing a fuel-air mixture into said first duct; a second duct extending between the second inlet port in the combustion chamber and said crankcase chamber; and a second admission port communicating with said crankcase chamber for introducing air into said crankcase chamber, communication between said combustion chamber and said crankcase chamber through said first and said second ducts being controlled by movement of said piston, the arrangement of said first and second second inlet portions being such that air introduced into said combustion chamber through said second duct substantially separates a fuel-air mixture introduced into said combustion chamber through said first duct from gases being exhausted through said exhaust port.
Claim 3
Dependent Claim 31 words
A two-stroke internal combustion engine as claimed in claim 1, in which the further admission port leads directly to the crankcase chamber and is operative to admit air to the chamber.
Claim 4
Dependent Claim 20 words
A two-stroke internal combustion engine as claimed in claim 2, in which there are at least two further admission ports.
Claim 5
Dependent Claim 25 words
A two-stroke internal combustion engine as claimed in claim 1, 2, or 3 in which at least two exhaust ports lead from the combustion chamber.
Claim 6
Dependent Claim 32 words
A two-stroke internal combustion engine as claimed in 1, 2, or 3, in which the first mentioned admission port to the duct is operative to admit air and fuel to the duct.
Claim 7
Dependent Claim 22 words
A two-stroke internal combustion engine as claimed in claim 1 or 2 including means for admitting lubricant through the further admission port.
Claim 8
Dependent Claim 19 words
A two-stroke internal combustion engine as claimed in claim 1, 2, or 3 which is a single cylinder engine.
Claim 9
Dependent Claim 18 words
A two-stroke internal combustion engine as claimed in claim 1, 2, or 3, which is a multicylinder engine.
Claim 10
Dependent Claim 56 words
A two-stroke internal combustion engine as claimed in claim 1, 2, or 3, further comprising at least two exhaust ports leading from the combustion chamber and means for admitting lubricant through a further admission port, and in which the first mentioned admission port to the duct is operative to admit air and fuel to the duct.

References Cited (Backward Citations)

US1121584A Cited
US1296214A Cited
US3916851A Cited
DE2650834A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-03-02 1984-09-01 1985-03-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-03-02 1988-09-01 1989-03-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-03-02 1992-09-01 1993-03-03 $7700.00 Window Closed / Lapsed

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