US3869392A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter cartridge
Assignee: Knecht Filterwerk GmbH
•
Filing: 1973-01-29
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Granted: 1975-03-04
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Expires: 1993-01-29
Abstract
Abstract Cartridge for internal combustion engines, in which the filter body is formed from a strip of filter material which is pleated or folded in a zig-zag manner to have its folds relatively close to one another in a dense arrangement. The body is carried by a plastic frame which is provided with a clamping flange in which the edges of the filter paper are embedded during the molding of the frame.
Inventors
- 👤 Max Wolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:53
CPC Classifications
F; F02; F02M; F02M35/00; F02M35/02; F02M35/024; B; B01; B01D; B01D29/00; B01D29/11; B01D29/111; B01D2201/00; B01D2201/12; Y; Y10; Y10S; Y10S55/00; Y10S55/31
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
173 words
A filter cartridge comprising a filter body consisting of a sheet of impregnated fibrous filter material pleated in a dense, zig-zag arrangement of uniform parallel folds forming a selfsupporting rectangular body terminating in a complete fold at each of its transverse ends and an edge at each of its longitudinal ends, a metal reinforcing strip bent along its length to form a V-shaped member having two legs of a width equal to that of said fold and of a length substantially equal to that of said transverse end folds, said metal strip being located solely over each of said transverse end folds, a frame consisting of a flexible molded plastic material surrounding the perimeter of said filter body, said frame extending over the longitudinal edges and embedding same therein and having a groove for receiving one leg of each of said transverse end folds and said associated metal strip together and embedding the same therein, the other leg of said end fold and said metal strip extending into the interior of said frame.
Claim 2
Dependent Claim
173 words
A filter cartridge comprising a filter body consisting of a sheet of impregnated fibrous filter material pleated in a dense, zig-zag arrangement of uniform parallel folds forming a selfsupporting rectangular body terminating in a complete fold at each of its transverse ends and an edge at each of its longitudinal ends, a metal reinforcing strip bent along its length to form a V-shaped member having two legs of a width equal to that of said fold and of a length substantially equal to that of said transverse end folds, said metal strip being located solely over each of said transverse end folds, a frame consisting of a flexible molded plastic material surrounding the perimeter of said filter body, said frame extending over the longitudinal edges and embedding same therein and having a groove for receiving one leg of each of said transverse end folds and said associated metal strip together and embedding the same therein, the other leg of said end fold and said metal strip extending into the interior of said frame.
Claim 3
Dependent Claim
24 words
A filter cartridge according to claim 1, wherein the frame comprises a plastic material molded in situ about the end fold said metal strip.
References Cited (Backward Citations)
US3389031A
Cited
US3747772A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-03 | 1978-09-02 | 1979-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-03 | 1982-09-02 | 1983-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-03 | 1986-09-02 | 1987-03-04 | $7700.00 | Window Closed / Lapsed |