Patent US795553A successfully refreshed from Google Patents.
US4158632A
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Filter for use in filtration of molten metal
Assignee: Rio Tinto Switzerland AG
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Filing: 1978-04-26
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Granted: 1979-06-19
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Expires: 1998-04-26
Abstract
Abstract The disclosure teaches an improved filter-type media which is characterized by a plurality of holes of equal size which are substantially larger than the pore size of the filter-type media thereby providing a preferential path through the filter-type media.
Inventors
- 👤 Jonathan A. Dantzig
- 👤 Derek E. Tyler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:10
CPC Classifications
C; C22; C22B; C22B9/00; C22B9/02; C22B9/023; C04; C04B; C04B38/00; C04B38/0051; C22B21/00; C22B21/06; C22B21/066; C04B2111/00; C04B2111/00474; C04B2111/00793; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
114 words
An improved filter plate means for use in the filtration and degassing of molten metal with a fluxing gas consisting essentially of at least one open cell structure consisting of a plurality of interconnected voids surrounded by a web consisting essentially of ceramic material and further including an array of holes of predetermined sizing and spacing, said holes being substantially larger than the pore size of said filter plate means; said predetermined sizing and spacing providing a preferential path through said filter plate means for said fluxing gas in countercurrent flow to said molten metal while at the same time passing substantially all of said molten metal through said pores of said filter plate.
Claim 2
Dependent Claim
114 words
An improved filter plate means for use in the filtration and degassing of molten metal with a fluxing gas consisting essentially of at least one open cell structure consisting of a plurality of interconnected voids surrounded by a web consisting essentially of ceramic material and further including an array of holes of predetermined sizing and spacing, said holes being substantially larger than the pore size of said filter plate means; said predetermined sizing and spacing providing a preferential path through said filter plate means for said fluxing gas in countercurrent flow to said molten metal while at the same time passing substantially all of said molten metal through said pores of said filter plate.
Claim 3
Dependent Claim
16 words
An improved filter plate means according to claim 1 wherein said holes are of equal size.
Claim 4
Dependent Claim
20 words
An improved filter plate means according to claim 2 wherein said hole size is from about 0.10" to about 0.45".
Claim 5
Dependent Claim
47 words
An improved filter plate means according to claim 4 wherein said filter plate means has an air permeability in the range of 400 to 8000×10 -7 cm 2 , a porosity of 0.80 to 0.95 and a pore size of 5 to 45 pores per linear inch.
References Cited (Backward Citations)
US4062771A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-06-18 | 1982-12-18 | 1983-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-18 | 1986-12-18 | 1987-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-18 | 1990-12-18 | 1991-06-19 | $7700.00 | Window Closed / Lapsed |