US5589143A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust gas purification apparatus for internal combustion engine
Assignee: Denso Corp
•
Filing: 1995-05-02
•
Granted: 1996-12-31
•
Expires: 2015-05-02
Abstract
Abstract An exhaust gas purification apparatus has a catalyst unit provided in an exhaust pipe of an engine and an absorbent provided downstream of the catalyst unit. When the engine is in a cool state, HC emitted from the engine is absorbed by the absorbent. After the engine is warmed up, the absorbed HC is desorbed by heat of an exhaust gas and returned to an upstream side of the catalyst unit the HC by heat of an exhaust gas.
Inventors
- 👤 Hiroshi Mori
- 👤 Masakazu Tanaka
- 👤 Mamoru Mabuchi
- 👤 Makoto Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:40
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/9481; F; F01; F01N; F01N3/00; F01N3/08; F01N3/0807; F01N3/0814; F01N3/0828; F01N3/0835; F01N3/0871; F01N3/0878; F01N3/10; F01N3/24; F01N3/28; F01N3/2892; F01N2240/00; F01N2240/02; F01N2240/10; F01N2250/00; F01N2250/12; F01N2410/00; F01N2410/12; F01N3/18; F01N3/20; F01N3/2839; F01N3/2842; F02; F02B; F02B1/00; F02B1/02; F02B1/04; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
226 words
An apparatus for purifying an exhaust gas emitted from an internal combustion engine having an exhaust gas flow path, the apparatus comprising: a catalyst unit provided in an exhaust gas flow path; a bypass passage having first and second ends, each in communication with the exhaust gas flow path downstream of said catalyst unit; an absorbent provided in said bypass passage for absorbing a hydrocarbon ("HC") gas contained in an exhaust gas emitted from an internal combustion engine: a circulation passage having first and second ends, said first end being connected to a location in the exhaust gas flow path upstream of said catalyst unit, and said second end being connected to said bypass passage, downstream of said absorbent; a circulation controlling means provided in said circulation passage for intermittently opening and closing said circulation passage in correspondence with an exhaust gas pulsation occurring at said location in the exhaust gas flow path upstream of said catalyst unit where said first end of said circulation passage is connected; exhaust gas flow path change-over means for directing the exhaust gas to flow through said bypass passage when a temperature of said exhaust gas is lower than a threshold temperature, and for directing the exhaust gas to flow only in the exhaust gas flow path when a temperature of the exhaust gas is higher than the threshold temperature.
Claim 2
Independent Claim
226 words
An apparatus for purifying an exhaust gas emitted from an internal combustion engine having an exhaust gas flow path, the apparatus comprising: a catalyst unit provided in an exhaust gas flow path; a bypass passage having first and second ends, each in communication with the exhaust gas flow path downstream of said catalyst unit; an absorbent provided in said bypass passage for absorbing a hydrocarbon ("HC") gas contained in an exhaust gas emitted from an internal combustion engine: a circulation passage having first and second ends, said first end being connected to a location in the exhaust gas flow path upstream of said catalyst unit, and said second end being connected to said bypass passage, downstream of said absorbent; a circulation controlling means provided in said circulation passage for intermittently opening and closing said circulation passage in correspondence with an exhaust gas pulsation occurring at said location in the exhaust gas flow path upstream of said catalyst unit where said first end of said circulation passage is connected; exhaust gas flow path change-over means for directing the exhaust gas to flow through said bypass passage when a temperature of said exhaust gas is lower than a threshold temperature, and for directing the exhaust gas to flow only in the exhaust gas flow path when a temperature of the exhaust gas is higher than the threshold temperature.
Claim 3
Dependent Claim
21 words
An apparatus according to claim 1, wherein said exhaust gas flow path change-over means is disposed only downstream of said absorbent.
Claim 4
Dependent Claim
11 words
An apparatus according to claim 1, wherein said absorbent is temperature-sensitive.
Claim 5
Dependent Claim
49 words
An apparatus according to claim 1, wherein said circulation controlling means comprises a one-way valve, said one-way valve being operable in accordance with a pressure in said exhaust gas flow path such that said one-way valve is opened when the exhaust gas flow path is put under negative pressure.
Claim 6
Dependent Claim
29 words
An apparatus according to claim 1, wherein said location in the exhaust gas flow path upstream of said catalyst unit is an exhaust manifold of the internal combustion engine.
References Cited (Backward Citations)
US3657892A
Cited
US3645098A
Cited
US3699683A
Cited
US3813226A
Cited
US3892536A
Cited
JPS5413815A
Cited
EP0318462A2
Cited
DE3627637A1
Cited
US4934142A
Cited
JPH0275327A
Cited
US4985210A
Cited
JPH0286910A
Cited
JPH02135126A
Cited
EP0378797A1
Cited
EP0422432A1
Cited
JPH03141816A
Cited
US5140811A
Cited
US5158753A
Cited
JPH03194113A
Cited
JPH0417710A
Cited
EP0460542A2
Cited
US5125231A
Cited
US5051244A
Cited
EP0485179B1
Cited
JPH04311618A
Cited
DE4113293A1
Cited
JPH0544446A
Cited
JPH0557138A
Cited
JPH05149131A
Cited
US5142864A
Cited
JPH0693850A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-12-31 | 2000-07-01 | 2000-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-31 | 2004-07-01 | 2004-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-31 | 2008-07-01 | 2008-12-31 | $7700.00 | Window Closed / Lapsed |