Patent US3847577A successfully refreshed from Google Patents.
US3847577A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air filter
Assignee: Inter-Nation Research Corp
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Filing: 1973-02-02
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Granted: 1974-11-12
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Expires: 1993-02-02
Abstract
Abstract An air filter for use with internal combustion engines is constructed which comprises a housing having an air inlet and a filtered air outlet, a plurality of filter elements placed one atop the other inside the housing and means for conveying filtered air to the engine.
Inventors
- 👤 E Hansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:04
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/24; B01D46/2403; B01D46/2411; B01D46/2414; B01D46/56; B01D46/58; B01D46/60; F; F02; F02M; F02M35/00; F02M35/02; F02M35/024; F02M35/10; F02M35/10006; F02M35/10013; F02M35/16; F02M35/164; B01D2279/00; B01D2279/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
155 words
An air filter for use with internal combustion engines which comprises a substantially cylindrical housing having a closed bottom and an open top, a filtered air outlet disposed through the cylindrical surface, a top cover having a centrally disposed opening therethrough secured to the top of the housing, a plurality of tubular filter elements having a central opening and a perforated cover extending the length of each filter element, said filter elements being placed one atop the other inside the housing and secured to the bottom wall and to each other, said filter elements being substantially equidistantly spaced from the interior cylindrical walls of the housing, and an intake tube disposed through the centrally disposed opening in the cover such that a portion of the intake tube is disposed within the central opening of the uppermost filter element and the remainder of the intake tube extends upward through the centrally disposed opening in the cover.
Claim 2
Dependent Claim
155 words
An air filter for use with internal combustion engines which comprises a substantially cylindrical housing having a closed bottom and an open top, a filtered air outlet disposed through the cylindrical surface, a top cover having a centrally disposed opening therethrough secured to the top of the housing, a plurality of tubular filter elements having a central opening and a perforated cover extending the length of each filter element, said filter elements being placed one atop the other inside the housing and secured to the bottom wall and to each other, said filter elements being substantially equidistantly spaced from the interior cylindrical walls of the housing, and an intake tube disposed through the centrally disposed opening in the cover such that a portion of the intake tube is disposed within the central opening of the uppermost filter element and the remainder of the intake tube extends upward through the centrally disposed opening in the cover.
Claim 3
Dependent Claim
16 words
An air filter according to claim 1 wherein the filter elements are substantially cylindrical filter cartridges.
Claim 4
Dependent Claim
16 words
An air filter according to claim 2 wherein adjacent filter cartridges are secured to one another.
Claim 5
Dependent Claim
19 words
An air filter according to claim 3 which comprises a ''''rain-hat'''' secured to the top of the intake tube.
Claim 6
Dependent Claim
28 words
An air filter according to claim 3 wherein the filter cartridges have perforated inner and outer liners through which the filtered air passes to the filtered air outlet.
Claim 7
Dependent Claim
29 words
An air filter according to claim 1 which comprises an air pre-cleaner secured to the top cover so that the intake tube extends into the interior of the pre-cleaner.
Claim 8
Dependent Claim
19 words
An air filter according to claim 5 which comprises a ''''rain-hat'''' secured to the top of the air pre-cleaner.
References Cited (Backward Citations)
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Cited
US1209911A
Cited
DE616696C
Cited
US2990032A
Cited
GB882647A
Cited
GB1000575A
Cited
US3494114A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-11 | 1978-05-13 | 1978-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-11 | 1982-05-13 | 1982-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-11 | 1986-05-13 | 1986-11-12 | $7700.00 | Window Closed / Lapsed |