US4052153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat resistant crucible
Assignee: Rio Tinto Switzerland AG
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Filing: 1976-02-26
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Granted: 1977-10-04
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Expires: 1996-02-26
Abstract
Abstract A crucible, for use in heating and/or retaining melts at elevated temperatures, includes a hollow holding member composed of a heat resistant material, and a thin-walled insert composed of a substance chemically resistant to oxygen and oxidizing substances and being removably supported in the holding member.
Inventors
- 👤 Werner J. Borer
- 👤 Tibor Kugler
- 👤 Walter Schmidt
- 👤 Walter Stahlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:08
CPC Classifications
F; F27; F27B; F27B14/00; F27B14/08; F27B14/10
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
69 words
A crucible, for use in heating and/or retaining melts at elevated temperatures, comprising in combination: a holding member composed of a heat-resistant material open at the bottom; a fire-proof base-plate removably positioned below said holding member and operable to close said bottom; and a thin-walled insert cup composed of a substance chemically resistant to oxygen and oxidizing substances and being removably supported in said holding member above said base-plate.
Claim 2
Dependent Claim
69 words
A crucible, for use in heating and/or retaining melts at elevated temperatures, comprising in combination: a holding member composed of a heat-resistant material open at the bottom; a fire-proof base-plate removably positioned below said holding member and operable to close said bottom; and a thin-walled insert cup composed of a substance chemically resistant to oxygen and oxidizing substances and being removably supported in said holding member above said base-plate.
Claim 3
Dependent Claim
23 words
The crucible as claimed in claim 1, wherein said material is chemically resistant to oxidation at elevated temperatures and includes a metallic component.
Claim 4
Dependent Claim
14 words
The crucible as claimed in claim 1, wherein said material comprises a ceramic oxide.
Claim 5
Dependent Claim
27 words
The crucible as claimed in claim 3, wherein said ceramic oxide is plasma sprayed zirconium oxide or aluminum oxide and at least one metallic layer embedded therein.
Claim 6
Dependent Claim
21 words
The crucible as claimed in claim 4, wherein said metallic layer is a platinum metal and extends through said holding member.
Claim 7
Dependent Claim
30 words
The crucible as claimed in claim 5, wherein there are a plurality of said metallic layers each being cylindrical and approximately concentric with respect to the axis of said insert.
Claim 8
Dependent Claim
24 words
The crucible as claimed in claim 5, wherein there are a plurality of the metal layers each being a ring disposed about said insert.
Claim 9
Dependent Claim
23 words
The crucible as claimed in claim 5, wherein there are a plurality of metallic layers each being approximately helical and composed of iridium.
Claim 10
Dependent Claim
20 words
The crucible as claimed in claim 1, further comprising a protective layer disposed on the surface of said holding member.
Claim 11
Dependent Claim
18 words
The crucible as claimed in claim 9, wherein the width of said protective layer is approximately 0.3 mm.
Claim 12
Dependent Claim
21 words
The crucible as claimed in claim 1, further comprising an intermediate layer disposed between said insert cup and said holding member.
Claim 13
Dependent Claim
14 words
The crucible as claimed in claim 11, wherein said intermediate layer is a liquid.
Claim 14
Dependent Claim
13 words
The crucible as claimed in claim 1 wherein said base-plate comprises magnesium oxide.
Claim 15
Dependent Claim
15 words
The crucible as claimed in claim 1 wherein said thin-walled insert is composed of iridium.
Claim 16
Dependent Claim
17 words
The crucible as claimed in claim 1 wherein the thickness of said insert cup is approximately 0.3mm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-03 | 1981-04-04 | 1981-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-03 | 1985-04-04 | 1985-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-03 | 1989-04-04 | 1989-10-04 | $7700.00 | Window Closed / Lapsed |