US3791145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for reducing exhaust noxious emission of rotary engine and the system therefor
Assignee: Mazda Motor Corp
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Filing: 1972-03-08
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Granted: 1974-02-12
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Expires: 1992-03-08
Abstract
Abstract Method and system for reducing unburned and partially burned noxious gases inevitably contained in engine exhaust gases of a rotary engine having an exhaust gas cleaner in its exhaust system. In the method and system, a fresh air-fuel mixture existing in the engine chamber is periodically introduced into the exhaust system directly into or upstream of the exhaust gas cleaner in response to the compression condition of the engine chamber, thus improving the afterburning condition of the exhaust gas cleaner through warming-up. For this purpose, an enriched mixture left behind in a trailing portion of the engine chamber may exclusively be drawn into the cleaner so as to uniformalize the mixture ratio distribution in the whole engine chamber. Furthermore, the mixture may be shut off when the operating temperature of the cleaner is above a predetermined level dictating that the warming-up thereof is completed.
Inventors
- 👤 K Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:56
CPC Classifications
F; F01; F01N; F01N9/00; F01N3/00; F01N3/08; F01N3/10; F01N3/18; F01N3/20; F01N3/2006; F01N3/2033; F01N3/22; F01N3/222; F01N3/24; F01N3/26; F01N3/30; F01N3/32; F02; F02B; F02B53/00; F01N2610/00; F01N2610/14; F01N3/36; F01N3/38; F02B2053/005; F02B2730/00; F02B2730/01; F02B2730/018; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40; Y10; Y10S; Y10S60/00; Y10S60/901
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
168 words
A system for reducing unburned and partially burned gases contained in engine exhaust gases of an internal combustion engine of rotary type having an exhaust gas cleaner in its exhaust system, said system comprising: a bypass conduit having an inlet port open into an engine chamber under compression and an outlet port open into an exhaust system for providing fluid communication therebetween; and control means responsive to the compression condition of said engine chamber for periodically permitting said fluid communication so as to introduce by way of said bypass conduit into said exhaust gas cleaner a fresh air-fuel mixture from said engine chamber, wherein said control means includes a pressure relief valve mounted in said bypass conduit and responsive directly to the compression pressure in said engine chamber for effecting the periodical introduction of said fresh air-fuel mixture when said compression pressure is above a predetermined level lower than its maximum; whereby thee unburned and partially burned gases are afterburned to a minimum in said exhaust gas cleaner.
Claim 2
Independent Claim
168 words
A system for reducing unburned and partially burned gases contained in engine exhaust gases of an internal combustion engine of rotary type having an exhaust gas cleaner in its exhaust system, said system comprising: a bypass conduit having an inlet port open into an engine chamber under compression and an outlet port open into an exhaust system for providing fluid communication therebetween; and control means responsive to the compression condition of said engine chamber for periodically permitting said fluid communication so as to introduce by way of said bypass conduit into said exhaust gas cleaner a fresh air-fuel mixture from said engine chamber, wherein said control means includes a pressure relief valve mounted in said bypass conduit and responsive directly to the compression pressure in said engine chamber for effecting the periodical introduction of said fresh air-fuel mixture when said compression pressure is above a predetermined level lower than its maximum; whereby thee unburned and partially burned gases are afterburned to a minimum in said exhaust gas cleaner.
Claim 3
Independent Claim
168 words
A system for reducing unburned and partially burned gases contained in engine exhaust gases of an internal combustion engine of rotary type having an exhaust gas cleaner in its exhaust system, said system comprising: a bypass conduit having an inlet port open into an engine chamber under compression and an outlet port open into an exhaust system for providing fluid communication therebetween; and control means responsive to the compression condition of said engine chamber for periodically permitting said fluid communication so as to introduce by way of said bypass conduit into said exhaust gas cleaner a fresh air-fuel mixture from said engine chamber, wherein said control means includes valve means mounted in said bypass conduit and responsive to the crank angle of said internal combustion engine for effecting the periodical introduction of said fresh air-fuel mixture when said crank angle is below a predetermined level dictating anteriority to the T.D.C. point; whereby the unburned and partially burned gases are afterburned to a minimum in said exhaust gas cleaner.
Claim 4
Independent Claim
168 words
A system for reducing unburned and partially burned gases contained in engine exhaust gases of an internal combustion engine of rotary type having an exhaust gas cleaner in its exhaust system, said system comprising: a bypass conduit having an inlet port open into an engine chamber under compression and an outlet port open into an exhaust system for providing fluid communication therebetween; and control means responsive to the compression condition of said engine chamber for periodically permitting said fluid communication so as to introduce by way of said bypass conduit into said exhaust gas cleaner a fresh air-fuel mixture from said engine chamber, wherein said control means includes valve means mounted in said bypass conduit and responsive to the crank angle of said internal combustion engine for effecting the periodical introduction of said fresh air-fuel mixture when said crank angle is below a predetermined level dictating anteriority to the T.D.C. point; whereby the unburned and partially burned gases are afterburned to a minimum in said exhaust gas cleaner.
Claim 5
Independent Claim
160 words
A system for reducing unburned and partially burned gases contained in engine exhaust gases of an internal combustion engine of rotary type having an exhaust gas cleaner in its exhaust system, said system comprising: a bypass conduit having an inlet port open into an engine chamber under compression and an outlet port open into an exhaust system for providing fluid communciation therebetween, wherein the inlet port of said bypass conduit is located in a trailing portion of an engine housing defining said engine chamber for admitting therethrough an enriched fresh air-fuel mixture left behind in the trailing portion of said engine chamber; and control means responsive to the compression condition of said engine chamber for periodically permitting said fluid communication so as to introduce by way of said bypass conduit into said exhaust gas cleaner a fresh air-fuel mixture from said engine chamber, whereby the unburned and partially burned gases are afterburned to a minimum in said exhaust gas cleaner.
Claim 6
Independent Claim
160 words
A system for reducing unburned and partially burned gases contained in engine exhaust gases of an internal combustion engine of rotary type having an exhaust gas cleaner in its exhaust system, said system comprising: a bypass conduit having an inlet port open into an engine chamber under compression and an outlet port open into an exhaust system for providing fluid communciation therebetween, wherein the inlet port of said bypass conduit is located in a trailing portion of an engine housing defining said engine chamber for admitting therethrough an enriched fresh air-fuel mixture left behind in the trailing portion of said engine chamber; and control means responsive to the compression condition of said engine chamber for periodically permitting said fluid communication so as to introduce by way of said bypass conduit into said exhaust gas cleaner a fresh air-fuel mixture from said engine chamber, whereby the unburned and partially burned gases are afterburned to a minimum in said exhaust gas cleaner.
Claim 7
Dependent Claim
50 words
A system according to claim 2, further comprising shut-off means responsive to the operating temperature of said exhaust gas cleaner for shutting off the introduction of said fresh air-fuel mixture when said operating temperature is above a predetermined level dictating that the warming-up of said exhaust gas cleaner is completed.
Claim 8
Dependent Claim
48 words
A system according to claim 2, wherein said valve means includes a solenoid valve adapted to open when energized, and a crank angle sensor sensing said crank angle for supplying an electric signal to said solenoid valve for its energization when said crank angle reaches said predetermined level.
Claim 9
Dependent Claim
48 words
A system according to claim 2, wherein said valve means includes a mechanical valve adapted to open when actuated, and a mechanical linkage associated with the rotation of the rotor of said internal combustion engine for actuating said mechanical valve when said crank angle reaches said predetermined level.
Claim 10
Dependent Claim
46 words
A system according to claim 3, further comprising secondary air means for introducing fresh secondary air into said exhaust system upstream of said exhaust gas cleaner in a manner to sufficiently admix said fresh secondary air with sAid engine exhaust gases containing said fresh air-fuel mixture.
Claim 11
Dependent Claim
76 words
A system according to claim 7, wherein said secondary air means includes a secondary air conduit having an outlet port open into said exhaust system in the vicinity of the outlet port of said bypass conduit, and an air pump having fluid communication with said secondary air conduit for pumping out therethrough said fresh secondary air having a pressure level higher than a probable exhaust back pressure in the exhaust port of said internal combustion engine.
Claim 12
Dependent Claim
35 words
A system according to claim 8, wherein said secondary air means further includes an air container mounted between said secondary air conduit and air pump for temporarily storing said fresh secondary air before its introduction.
Claim 13
Dependent Claim
50 words
A system according to claim 3, further comprising shut-off means responsive to the operating temperature of said exhaust gas cleaner for shutting off the introduction of said fresh air-fuel mixture when said operating temperature is above a predetermined level dictating that the warming-up of said exhaust gas cleaner is completed.
Claim 14
Dependent Claim
57 words
A system according to claim 10, wherein said shut-off means includes a shut-off valve mounted said bypass conduit in series with said control means and adapted to close when actuated, and a warming-up sensor sensing the operating temperature of said exhaust gas cleaner for actuating said shut-off valve when said operating temperature is above said predetermined level.
Claim 15
Dependent Claim
35 words
A system according to claim 11, wherein said warming-up sensor is located adjacent to an engine housing defining said engine chamber for sensing said operating temperature in terms of the temperature of said engine housing.
Claim 16
Dependent Claim
32 words
A system according to claim 11, wherein said warming-up sensor is located adjacent to said exhaust system for sensing said operating temperature in terms of the temperature of said engine exhaust gases.
Claim 17
Dependent Claim
33 words
A system according to claim 11, wherein said warming-up sensor is located adjacent to said exhaust gas cleaner for sensing said operating temperature in terms of the temperature of said exhaust gas cleaner.
Claim 18
Dependent Claim
23 words
A system according to claim 11, wherein said warming-up sensor includes a mechanical element mechanically linked with said shut-off valve for its actuation.
Claim 19
Dependent Claim
19 words
A system according to claim 15, wherein said mechanical element includes a bimetal element for sensing said operating temperature.
Claim 20
Dependent Claim
20 words
A system according to claim 15, wherein said mechanical element includes a thermal expansion element for sensing said operating temperature.
Claim 21
Dependent Claim
26 words
A system according to claim 11, wherein said warming-up sensor includes an electric element for supplying an electric signal to said shut-off valve for its actuation.
Claim 22
Dependent Claim
18 words
A system according to claim 18, wherein said electric element includes a thermistor for sensing said operating temperature.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |