US4456531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter and a manufacturing method therefor
Assignee: Totoku Electric Co Ltd
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Filing: 1981-12-09
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Granted: 1984-06-26
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Expires: 2001-12-09
Abstract
Abstract A filter is disclosed which is capable of withstanding repeated use by cleaning. The filter is so constructed that around a frame body is wound a filter wire at a constant slit space of less than 40 with a maximum error of 50%. A method for manufacturing such a filter is also disclosed which comprises winding, on a frame body, a filter wire paired with a spacer wire for keeping the slit space of said filter wire constant in such a manner that each turn is in contact with adjacent turns; and removing the spacer wire alone by chemical or physical means while holding these wires fixed so as to obtain a filter with a smaller slit space error.
Inventors
- 👤 Misao Kubota
- 👤 Kazuhiko Terao
- 👤 Kenji Shimada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:53
CPC Classifications
B; B01; B01D; B01D29/00; B01D29/44; B01D29/48
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
144 words
A filter obtained by a method which comprises the steps of: (a) helically winding a filter wire and a spacer wire on a frame body such that the two wires are in contact with each other all along their lengths and such that each turn of the two wires is in contact with the adjacent turns on either side all along the length of the filter, the spacer wire being formed of a material which is different than the material of which the filter wire is formed and the longitudinal slit distance between adjacent turns of the filter wire being made constant by the dimensions of the spacer wire interposed between adjacent turns of the filter wire, then (b) removing the spacer wire without disturbing the spacing between adjacent turns of the filter wire by use of the different properties of the two wires.
Claim 2
Dependent Claim
144 words
A filter obtained by a method which comprises the steps of: (a) helically winding a filter wire and a spacer wire on a frame body such that the two wires are in contact with each other all along their lengths and such that each turn of the two wires is in contact with the adjacent turns on either side all along the length of the filter, the spacer wire being formed of a material which is different than the material of which the filter wire is formed and the longitudinal slit distance between adjacent turns of the filter wire being made constant by the dimensions of the spacer wire interposed between adjacent turns of the filter wire, then (b) removing the spacer wire without disturbing the spacing between adjacent turns of the filter wire by use of the different properties of the two wires.
Claim 3
Dependent Claim
20 words
A filter wire as recited in claim 1 wherein the frame body is made of metal or a plastic material.
Claim 4
Dependent Claim
19 words
A filter as recited in claim 1 wherein the filter wire is made of a metal or plastic material.
Claim 5
Dependent Claim
21 words
A filter as recited in claim 1 wherein the frame body comprises a polygonal prism each side of which is concave.
Claim 6
Dependent Claim
15 words
A filter as recited in claim 4 wherein the frame body comprises a rectangular prism.
Claim 7
Dependent Claim
15 words
A filter as recited in claim 4 wherein the frame body comprises a hexagonal prism.
Claim 8
Dependent Claim
28 words
A filter as recited in claim 1 wherein at least one end of the filter is closed with a lid body having a cleaned substance outlet port therein.
Claim 9
Dependent Claim
49 words
A filter as recited in claim 1 wherein one end of the filter is closed with a lid body having a cleaned substance outlet port therein and the other end of the filter is closed with another lid body having a compressed air inlet port therein for reverse cleaning.
Claim 10
Dependent Claim
31 words
A filter obtained by the method recited in claim 1 wherein said method comprises the further step of fixing the filter wire to the frame body before removing the spacer wire.
Claim 11
Dependent Claim
19 words
A filter as recited in claim 1 wherein the filter wire is larger in diameter than the spacer wire.
Claim 12
Dependent Claim
29 words
A filter obtained by the method recited in claim 10 and comprising the further step of fixing a space-holding wire to the filter wire before removing the spacer wire.
Claim 13
Dependent Claim
24 words
A filter as recited in claim 11 wherein the space-holding wire is wound helically around, transversely to, and radially outwardly of the filter wire.
Claim 14
Dependent Claim
34 words
A filter as recited in claim 1 wherein: (a) the spacer wire is physically different from the filter wire and (b) the spacer wire is removed by use of a different physical property thereof.
Claim 15
Dependent Claim
34 words
A filter as recited in claim 1 wherein: (a) the spacer wire is chemically different from the filter wire and (b) the spacer wire is removed by use of a different chemical property thereof.
Claim 16
Dependent Claim
19 words
A filter as recited in claim 1 wherein the filter wire makes substantially point contacts with the frame body.
Claim 17
Dependent Claim
33 words
A filter as recited in claim 1 wherein the longitudinal slit distance between adjacent turns of the filter wire is less than 40 microns and is constant with a maximum error of 50%.
Claim 18
Dependent Claim
21 words
A filter as recited in claim 1 wherein the filter wire and spacer wire are wound on the frame body simultaneously.
References Cited (Backward Citations)
US2711253A
Cited
US3132099A
Cited
US3105289A
Cited
US3200952A
Cited
US3268999A
Cited
US3388448A
Cited
US3747770A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-26 | 1987-12-26 | 1988-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-26 | 1991-12-26 | 1992-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-26 | 1995-12-26 | 1996-06-26 | $7700.00 | Window Closed / Lapsed |