US3798879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air filter with electrostatic particle collection
Assignee: Buderus AG
•
Filing: 1971-11-29
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Granted: 1974-03-26
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Expires: 1991-11-29
Abstract
Abstract A filter, for purifying air at least in part by electrostatic collection of particulates contained therein, has at least one charged gas-permeable filter surface extending transversely to the gas stream and designed mechanically to retain the particles by interposing a surface in the path of the gas. The electrostatic field is applied in the direction of movement of the gas stream. The particles may be charged by an ionizing device at the upstream side of the apparatus.
Inventors
- 👤 Burbach G Schmidt
- 👤 A Jung
- 👤 E Ledwon
- 👤 W Rock
- 👤 H Hubert
- 👤 M Lapczyna
- 👤 H Strauss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:02
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/02; B03C3/04; B03C3/14; B03C3/155; Y; Y10; Y10S; Y10S55/00; Y10S55/45
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
128 words
A filter comprising conduit means for conducting a stream of air from an inlet side to an outlet side; at least one electrically conductive filter of metallic fibers mat spanning said path and perpendicular thereto while traversed by the gas stream; a counterelectrode in said conduit means upstream of said metallic fiber mat; means for generating a potential difference parallel to said gas stream between said electrodes in the region of said mat to cause particles in said gas stream to be drawn electrostatically to said mat; and an ultraviolet source in said conduit means upstream of said counterelectrode for generating ions in said gas stream, said counterelectrode including wires extending generally parallel to the direction of flow of said gas stream and reaching to said ultraviolet source.
Claim 2
Dependent Claim
128 words
A filter comprising conduit means for conducting a stream of air from an inlet side to an outlet side; at least one electrically conductive filter of metallic fibers mat spanning said path and perpendicular thereto while traversed by the gas stream; a counterelectrode in said conduit means upstream of said metallic fiber mat; means for generating a potential difference parallel to said gas stream between said electrodes in the region of said mat to cause particles in said gas stream to be drawn electrostatically to said mat; and an ultraviolet source in said conduit means upstream of said counterelectrode for generating ions in said gas stream, said counterelectrode including wires extending generally parallel to the direction of flow of said gas stream and reaching to said ultraviolet source.
Claim 3
Dependent Claim
24 words
The filter defined in claim 1 wherein said mat consists at least in part of electrically nonconductive fibers and electrically conductive fibers mixed therewith.
Claim 4
Dependent Claim
21 words
The filter defined in claim 1 wherein said mat is composed of electrically nonconductive fibers provided with a conductive metal coating.
Claim 5
Dependent Claim
16 words
The filter defined in claim 1 wherein said mat is composed of a steel-wire woven fabric.
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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) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |