US4398931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceramic fabric filter
Assignee: 3M Co
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Filing: 1982-05-19
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Granted: 1983-08-16
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Expires: 2002-05-19
Abstract
Abstract A filter assembly for removing particulate matter from high temperature gas streams is disclosed, said filter assembly comprising: a rigid, tubular frame or cage made of high temperature stable material, having a closed lower end, or optionally an open lower end, and adapted to be connected to a gas compartment at its open upper end, the cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less then 125 square millimeters, a filter element surrounding said cage and comprising a conformable, fabric tape of woven ceramic fibers tightly spiral-wound in an over-lapped wrap about the lateral surface of the cage, said filter element being a gas permeable, rigid, seamless, tubular structure having at least one open end, and a clamping means for securing the filter element to the lower end of the cage, the clamping means optionally forming an end cap for the lower end of the filter.
Inventors
- 👤 Thomas S. Shevlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:08
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/02; B01D46/04; B01D39/00; B01D39/08; B01D39/086; B01D39/14; B01D39/20; B01D39/2068; B01D39/2082; B01D46/0001; B01D46/66; B01D46/70; B01D46/71; B01D2239/00; B01D2239/06; B01D2239/065; B01D2239/0654; B01D2239/069; B01D2239/0695; B01D2265/00; B01D2265/02; B01D2265/024; B01D2265/025; Y; Y10; Y10S; Y10S55/00; Y10S55/45
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
125 words
A filter comprising: a rigid, tubular frame or cage made of high temperature stable material, having an upper end and a lower end, said upper end being open, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square millimeters, and a tubular, seamless filter element surrounding said cage and comprising a conformable, fabric tape of woven ceramic fibers and tightly spiral-wound in an over-lapped wrap about the lateral surface of said cage, said filter element being a gas permeable structure having at least one open end, the resultant filter being a gas permeable, rigid structure having at least one open end and suitable for high temperature filtering applications.
Claim 2
Dependent Claim
125 words
A filter comprising: a rigid, tubular frame or cage made of high temperature stable material, having an upper end and a lower end, said upper end being open, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square millimeters, and a tubular, seamless filter element surrounding said cage and comprising a conformable, fabric tape of woven ceramic fibers and tightly spiral-wound in an over-lapped wrap about the lateral surface of said cage, said filter element being a gas permeable structure having at least one open end, the resultant filter being a gas permeable, rigid structure having at least one open end and suitable for high temperature filtering applications.
Claim 3
Dependent Claim
14 words
The filter according to claim 1 wherein said cage is made of metal screen.
Claim 4
Dependent Claim
18 words
The filter according to claim 1 wherein the integrity of said filter is maintained up to 1150° C.
Claim 5
Dependent Claim
35 words
The filter according to claim 1 wherein said ceramic fibers are selected from the group consisting of continuous fused silica, alumina-silica, zirconia-silica, alumina-chromia-metal (IV) oxide, titania, thoria-silica-metal (III) oxide, graphite, silicon carbide, and alumina-boria-silica fibers.
Claim 6
Dependent Claim
14 words
The filter according to claim 1 wherein said ceramic fibers are alumina-boria-silica ceramic fibers.
Claim 7
Dependent Claim
12 words
The filter according to claim 1 wherein said ceramic fibers are alumina-silica.
Claim 8
Dependent Claim
15 words
The filter according to claim 1 wherein said lower end of said cage is closed.
Claim 9
Dependent Claim
15 words
The filter according to claim 1 wherein said lower end of said cage is open.
Claim 10
Dependent Claim
144 words
A filter assembly comprising: a rigid, tubular frame or cage made of high temperature stable material, having an upper end and a lower end, and adapted to be connected to a gas compartment at its open upper end, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square millimeters, a filter element surrounding said cage and comprising a conformable, fabric tape of woven ceramic fibers tightly spiral-wound in an over-lapped wrap about the lateral surface of said cage, said filter element being a gas permeable, rigid, seamless, tubular structure having at least one open end, and a clamping means for securing said filter element to the lower end of said cage, said clamping means optionally forming an end cap for the lower end of the resulting filter.
Claim 11
Dependent Claim
144 words
A filter assembly comprising: a rigid, tubular frame or cage made of high temperature stable material, having an upper end and a lower end, and adapted to be connected to a gas compartment at its open upper end, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square millimeters, a filter element surrounding said cage and comprising a conformable, fabric tape of woven ceramic fibers tightly spiral-wound in an over-lapped wrap about the lateral surface of said cage, said filter element being a gas permeable, rigid, seamless, tubular structure having at least one open end, and a clamping means for securing said filter element to the lower end of said cage, said clamping means optionally forming an end cap for the lower end of the resulting filter.
Claim 12
Dependent Claim
36 words
The filter assembly according to claim 9 wherein said ceramic fibers are selected from the group consisting of continuous fused silica, alumina-silica, zirconia-silica, alumina-chromia-metal (IV) oxide, titania, thoria-silica-metal (III) oxide, graphite, silicon carbide, and alumina-boria-silica fibers.
Claim 13
Dependent Claim
15 words
The filter assembly according to claim 9 wherein said ceramic fibers are alumina-boria-silica ceramic fibers.
Claim 14
Dependent Claim
13 words
The filter assembly according to claim 9 wherein said ceramic fibers are alumina-silica.
Claim 15
Dependent Claim
17 words
The filter assembly according to claim 9 wherein said assembly is part of a baghouse filter assembly.
Claim 16
Dependent Claim
16 words
The filter assembly according to claim 7 wherein said lower end of said cage is closed.
Claim 17
Dependent Claim
16 words
The filter assembly according to claim 9 wherein said lower end of said cage is open.
Claim 18
Dependent Claim
188 words
A filter assembly for cleaning by a periodic reverse purge of air, comprising: a rigid, elongated, tubular metal cage having a lower end and an upper end, and connected to a gas compartment by fastening means at its open upper end, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square millimeters, a filter element surrounding said cage and comprising a conformable, selvedge fabric tape of woven alumina-boria-silica fibers tightly spiral-wound in an over-lapped wrap about said lateral surface of said metal cage, said tape having a width in the range of 1.0 to 15 cm and a thickness in the range of 0.5 to 1.0 mm, said overlap being in the range of 0.25 to 7.5 cm, and the resultant filter element being a gas permeable, rigid, tubular structure open at one end, said alumina-boria-silica fibers having an alumia:boria mol ratio of 9:2 to 3:1.5, and containing up to 65 weight percent of silica, and a clamping means for securing said filter element to said lower end of said cage.
Claim 19
Dependent Claim
188 words
A filter assembly for cleaning by a periodic reverse purge of air, comprising: a rigid, elongated, tubular metal cage having a lower end and an upper end, and connected to a gas compartment by fastening means at its open upper end, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square millimeters, a filter element surrounding said cage and comprising a conformable, selvedge fabric tape of woven alumina-boria-silica fibers tightly spiral-wound in an over-lapped wrap about said lateral surface of said metal cage, said tape having a width in the range of 1.0 to 15 cm and a thickness in the range of 0.5 to 1.0 mm, said overlap being in the range of 0.25 to 7.5 cm, and the resultant filter element being a gas permeable, rigid, tubular structure open at one end, said alumina-boria-silica fibers having an alumia:boria mol ratio of 9:2 to 3:1.5, and containing up to 65 weight percent of silica, and a clamping means for securing said filter element to said lower end of said cage.
Claim 20
Dependent Claim
40 words
The filter assembly according to claim 14 wherein the closed lower end of said cage has openings therein and said clamping means further secures a sheet-like piece of fabric of woven ceramic fibers over said lower end of said cage.
Claim 21
Dependent Claim
16 words
The filter assembly according to claim 16 wherein said lower end of said cage is closed.
Claim 22
Dependent Claim
17 words
The filter assembly according to claim 16 wherein said lower end of said cage has openings therein.
Claim 23
Dependent Claim
124 words
A filter comprising: a rigid, tubular frame or cage made of high temperature stable material having a lower end and an open upper end, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square milimeters, and a tubular, seamless filter element surrounding said cage and comprising a conformable fabric tape of woven fibers of refractory metal wire and tightly spiral-wound in an over-lapped wrap about the lateral surface of said cage, said filter element being a gas permeable structure having at least one open end, the resultant filter being a gas permeable, rigid structure having at lest one open end and suitable for high temperature filtering applications.
Claim 24
Dependent Claim
124 words
A filter comprising: a rigid, tubular frame or cage made of high temperature stable material having a lower end and an open upper end, said cage having openings to provide at least 40 percent open area on its lateral surface, with each opening having an area of less than 125 square milimeters, and a tubular, seamless filter element surrounding said cage and comprising a conformable fabric tape of woven fibers of refractory metal wire and tightly spiral-wound in an over-lapped wrap about the lateral surface of said cage, said filter element being a gas permeable structure having at least one open end, the resultant filter being a gas permeable, rigid structure having at lest one open end and suitable for high temperature filtering applications.
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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) | 1986-08-15 | 1987-02-14 | 1987-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-15 | 1991-02-14 | 1991-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-15 | 1995-02-14 | 1995-08-16 | $7700.00 | Window Closed / Lapsed |