Patent EP0441401A1 successfully refreshed from Google Patents.
EP0441401A1
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Exhaust gas purification system for an internal combustion engine
Assignee: Toyota Motor Corp
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Filing: 1991-02-08
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Granted: —
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Expires: 2011-02-08
Abstract
Abstract An exhaust gas purification system for an internal combustion engine includes an engine (1) capable of fuel combustion at lean air-fuel ratios, a lean NOx catalyst (3) installed in an exhaust conduit (16) of the engine, an HC producing means (2, 4, 6, 11, 15, 21, 22, 23, 24, 25, 26, 30, 32) for producing hydrocarbons of low boiling points utilizing fuel for the engine, and an HC supply means (7, 8, 9, 10, 13, 27, 28, 29) for supplying the hydrocarbons of low boiling points to the exhaust conduit (16) upstream of the lean NOx catalyst (3). NOx reduction reaction needs hydrocarbons of low boiling points. The HC producing means produces hydrocarbons of low boiling points from diesel oil by cracking, fractional distillation, or both cracking and fractional distillation. The cracked and/or distilled fuel includes a large amount of hydrocarbons of low boiling points and increases NOx purification rate of the lean NOx catalyst (3) when the hydrocarbons of low boiling points are introduced into the exhaust conduit (3) by the HC supply means.
Inventors
- 👤 Sinya Hirota
- 👤 Tokuta Inoue
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 18:18
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/24; F01N3/36; B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01D53/9495; F01N3/18; F01N3/20; F01N3/206; F01N3/2066; F01N2240/00; F01N2240/02; F01N2240/30; F01N2370/00; F01N2370/02; F01N2370/04; F01N2610/00; F01N2610/03; F01N2610/10; F01N2610/14; F01N2610/1453; F01N2610/146; F01N2900/00; F01N2900/06; F01N2900/08; F02; F02B; F02B1/00; F02B1/02; F02B1/04; F02B3/00; F02B3/06; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
168 words
An exhaust gas purification system for an internal combustion engine wherein the internal combustion engine (1) is capable of fuel combustion at lean air-fuel ratios and has an exhaust manifold (14) and an exhaust conduit (16) connected to the manifold (14), characterized in that the exhaust gas purification system comprises: a catalyst (3) installed in the exhaust conduit (16) of the engine and constructed of zeolite carrying at least one kind of metal selected from transition metals and noble metals to reduce nitrogen oxides included in exhaust gas from the engine under oxidizing conditions and in the presence of hydrocarbons; an HC producing means (2, 4, 6, 11, 15, 21, 22, 23, 24, 25, 26, 30, 32) for producing hydrocarbons of low boiling points from fuel for combustion in the engine; and an HC supply means (7, 8, 9, 10, 13, 27, 28, 29) for supplying the hydrocarbons of low boiling points from produced by the HC producing means to the exhaust conduit (16) upstream of the catalyst.
Claim 2
Dependent Claim
45 words
An exhaust gas purification system for an internal combustion engine according to claim 1, wherein the HC producing means comprises means (2, 4, 6, 11, 15) for producing hydrocarbons of low boiling points by cracking at least a portion of the fuel for the engine.
Claim 3
Dependent Claim
42 words
An exhaust gas purification system for an internal combustion engine according to claim 2, wherein the HC producing means comprises a fuel cracking chamber (11) provided adjacent to and separated from the exhaust manifold (14) by a heat conductive manifold wall (17).
Claim 4
Dependent Claim
57 words
An exhaust gas purification system for an internal combustion engine according to claim 3, wherein the HC producing means includes an injection nozzle (6) provided at the fuel cracking chamber (11) for injecting fuel into the fuel cracking chamber (11) and a branch pipe (15) leading fuel from a fuel pump (2) to the injection nozzle (6).
Claim 5
Dependent Claim
51 words
An exhaust gas purification system for an internal combustion engine according to claim 2, wherein the HC supply means includes a pipe (7) extending from the fuel cracking chamber (11) to the exhaust conduit (16) upstream of the catalyst (3) and a flow control valve (9) installed in the pipe (7).
Claim 6
Dependent Claim
35 words
An exhaust gas purification system for an internal combustion engine according to claim 2, wherein the internal combustion engine (1) comprises a diesel engine, and the fuel for combustion in the engine comprises light oil.
Claim 7
Dependent Claim
49 words
An exhaust gas purification system for an internal combustion engine according to claim 1, wherein the HC producing means includes means (21, 22, 23, 24, 26) for producing hydrocarbons of low boiling points by fractional distillation of at least a portion of the fuel for combustion in the engine.
Claim 8
Dependent Claim
97 words
An exhaust gas purification system for an internal combustion engine according to claim 7, wherein the HC producing means comprises a fuel circulation pipe (21) for circulating at least a portion of the fuel for combustion in the engine, a heater (23) provided at a portion of the fuel circulation pipe so as to heat the circulated fuel to evaporate at least a portion of the circulated fuel, and a gas/liquid separator (24) provided in the fuel circulation pipe (21) downstream of the heater (23) for separating the evaporated portion from liquid components of the circulated fuel.
Claim 9
Dependent Claim
74 words
An exhaust gas purification system for an internal combustion engine according to claim 7, wherein the HC supply means comprises an HC injection nozzle (27) for injecting the hydrocarbons of low boiling points into the exhaust conduit (16) upstream of the catalyst (3), a pipe (28) for leading the hydrocarbons of low boiling points to the HC injection nozzle (27), and an HC supply pump (29) for pressurizing the hydrocarbons of low boiling points.
Claim 10
Dependent Claim
52 words
An exhaust gas purification system for an internal combustion engine according to claim 1, wherein the HC producing means includes means (24, 25, 26, 30, 32) for producing hydrocarbons of low boiling points by both cracking and fractional distillation of at least a portion of the fuel for combustion in the engine.
Claim 11
Dependent Claim
72 words
An exhaust gas purification system for an internal combustion engine according to claim 10, wherein the HC producing means includes a fuel pump (2), a fuel return pipe (30) connected to the fuel pump (2), a zigzag portion (32) formed in the fuel return pipe (30) in the vicinity of the exhaust manifold (14), and a gas/liquid separator (24) located in the fuel return pipe (30) downstream of the zigzag portion (32).
Claim 12
Dependent Claim
54 words
An exhaust gas purification system for an internal combustion engine according to claim 10, wherein the HC supply means (13, 27, 28, 29) includes an HC injection nozzle (27) provided at the exhaust conduit (16) upstream of the catalyst (3) and an HC supply pump (29) for pressurizing the hydrocarbons of low boiling points.
References Cited (Backward Citations)
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