Patent US5634952A successfully refreshed from Google Patents.
US5634952A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust gas filter and apparatus for treating exhaust gases using the same
Assignee: NGK Insulators Ltd
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Filing: 1995-06-06
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Granted: 1997-06-03
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Expires: 2015-06-06
Abstract
Abstract An imaginary plane dividing a profile of a rough surface of a filter into halves with equal volume is defined as a mean plane. Assuming cutting the filter with the mean plane, a ratio of the total cross-sectional area of the recesses appearing to the whole area of the mean plane is defined as a Valley Level. An exhaust gas filter having a surface with a Valley Level of at most 20%, a porosity of 40% to 55% and an average pore diameter of 5 μm to 50 μm effectively collects fine particles contained in exhaust gases discharged from internal combustion engines, such as diesel engines, with little pressure loss, and has an improved releasability of deposited fine particles and can be readily regenerated by flow of blowback air, with high efficiency. When the filter has a specified two-layer structure, the Valley Level is readily controllable.
Inventors
- 👤 Yoshiyuki Kasai
- 👤 Yoshiro Ono
- 👤 Ikuko Ishiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:21
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/02; F01N3/021; F01N3/023; F01N3/0233; F01N13/00; F01N13/011; F02; F02B; F02B3/00; F02B3/06; Y; Y10; Y10S; Y10S55/00; Y10S55/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
72 words
An exhaust gas filter for collecting fine particles contained in exhaust gases discharged from internal combustion engines, comprising a filter substrate and a filter layer provided on a surface of said filter substrate, said filter layer having a surface with a Valley Level of not more than 20%, and said filter substrate having a porosity of between 45% and 60% and an average pore diameter of between 10 μm and 80 μm.
Claim 2
Dependent Claim
72 words
An exhaust gas filter for collecting fine particles contained in exhaust gases discharged from internal combustion engines, comprising a filter substrate and a filter layer provided on a surface of said filter substrate, said filter layer having a surface with a Valley Level of not more than 20%, and said filter substrate having a porosity of between 45% and 60% and an average pore diameter of between 10 μm and 80 μm.
Claim 3
Dependent Claim
24 words
The exhaust gas filter according to claim 1, wherein said filter layer does not substantially block open-pores on the surface of said filter substrate.
Claim 4
Independent Claim
94 words
An apparatus for treating exhaust gases discharged from internal combustion engines, comprising an exhaust gas filter for collecting fine particles contained in the exhaust gases, and an air-blowback means to regenerate said exhaust gas filter, said exhaust gas filter comprising a filter substrate and a filter layer provided on a surface of said filter substrate, said filter layer having a surface with a Valley Level of not more than 20%, and said filter substrate having a porosity of between 45% and 60% and an average pore diameter of between 10 μm and 80 μm.
Claim 5
Independent Claim
94 words
An apparatus for treating exhaust gases discharged from internal combustion engines, comprising an exhaust gas filter for collecting fine particles contained in the exhaust gases, and an air-blowback means to regenerate said exhaust gas filter, said exhaust gas filter comprising a filter substrate and a filter layer provided on a surface of said filter substrate, said filter layer having a surface with a Valley Level of not more than 20%, and said filter substrate having a porosity of between 45% and 60% and an average pore diameter of between 10 μm and 80 μm.
Claim 6
Dependent Claim
18 words
The apparatus according to claim 3, wherein said internal combustion engines are diesel engines mounted on motor vehicles.
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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) | 2000-06-02 | 2000-12-02 | 2001-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-02 | 2004-12-02 | 2005-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-02 | 2008-12-02 | 2009-06-03 | $7700.00 | Window Closed / Lapsed |