Patent US4606743A successfully refreshed from Google Patents.
US4606743A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two stage engine air breather filter
Assignee: Individual
•
Filing: 1985-06-28
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Granted: 1986-08-19
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Expires: 2005-06-28
Abstract
Abstract An air filter for removing particulate matter from an airstream by cyclonic action and having replaceable primary and secondary filter elements.
Inventors
- 👤 Curtis F. Shuman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:06
CPC Classifications
B; B01; B01D; B01D50/00; B01D50/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
155 words
An air filter for filtering particulate matter from an airstream comprising: a cylindrical canister having an open upper end and a closed lower end forming a base; an unfiltered air inlet formed in the side wall of said canister; an air deflector disposed within said canister for directing the flow of air entering said canister via said unfiltered air inlet into a cyclonic path to swirl around the interior of said canister; a plurality of spaced collector baffles attached to the inner lower wall of said canister; a rigid cone-shaped screen supported in an inverted position by means in the open end of said canister; a cone-shaped primary filter element disposed over the exterior surface of said cone-shaped screen; a flat circular secondary filter pad covering the open base of said cone-shaped primary filter element; and a detachable cover member covering the open end of said canister and having a filtered air outlet formed therein.
Claim 2
Dependent Claim
155 words
An air filter for filtering particulate matter from an airstream comprising: a cylindrical canister having an open upper end and a closed lower end forming a base; an unfiltered air inlet formed in the side wall of said canister; an air deflector disposed within said canister for directing the flow of air entering said canister via said unfiltered air inlet into a cyclonic path to swirl around the interior of said canister; a plurality of spaced collector baffles attached to the inner lower wall of said canister; a rigid cone-shaped screen supported in an inverted position by means in the open end of said canister; a cone-shaped primary filter element disposed over the exterior surface of said cone-shaped screen; a flat circular secondary filter pad covering the open base of said cone-shaped primary filter element; and a detachable cover member covering the open end of said canister and having a filtered air outlet formed therein.
Claim 3
Dependent Claim
29 words
An air filter as set forth in claim 1 and further comprising a flat circular metallic mesh screen disposed between said secondary filter pad and said detachable cover member.
Claim 4
Dependent Claim
25 words
An air filter as set forth in claim 2 wherein said primary filter element and said secondary filter pad are formed of cellulose fiber material.
Claim 5
Dependent Claim
31 words
An air filter as set forth in claim 3 wherein said plurality of spaced collector baffles comprise four of said baffles equally spaced around said inner lower wall of said canister.
Claim 6
Dependent Claim
50 words
An air filter as set forth in claim 4 wherein each of said baffles comprise a wedge-shaped sheet metal member having folds therein to entrap particulate matter between said member and said inner lower wall of said canister and to guide said particulate matter towards the base of said canister.
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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) | 1989-08-18 | 1990-02-17 | 1990-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-18 | 1994-02-17 | 1994-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-18 | 1998-02-17 | 1998-08-19 | $7700.00 | Window Closed / Lapsed |