Patent US3662816A successfully refreshed from Google Patents.
US3662816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means for preventing core shift in casting articles
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1970-04-30
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Granted: 1972-05-16
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Expires: 1990-04-30
Abstract
Abstract Shell-type casting molds for producing hollow cast articles, the mold being built up by forming a low melting pattern about a ceramic core, inserting thin metal pins through the pattern and into engagement with the core, forming a shell mold about the resulting pattern so that the ends of the pins are anchored in the resulting shell mold, removing the meltable pattern, and casting the molten metal into the cavity thus produced whereby the molten metal dissolves the pins and no holes appear in the finished article.
Inventors
- 👤 Thomas H Bishop
- 👤 Kenneth K Young Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:39
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/02; B22C9/04; B22C21/00; B22C21/12; B22C21/14; B22C9/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A mold structure comprising a solid ceramic core, a one piece ceramic shell mold surrounding said core, and a plurality of thin metallic pins of uniform diameter anchored medially in the shell mold as a result of firing of a ceramic mold-making composition in the manufacture of such shell mold, the free ends of said pins extending into firm abutting engagement with said core to provide lateral support thereof.
Claim 2
Dependent Claim
69 words
A mold structure comprising a solid ceramic core, a one piece ceramic shell mold surrounding said core, and a plurality of thin metallic pins of uniform diameter anchored medially in the shell mold as a result of firing of a ceramic mold-making composition in the manufacture of such shell mold, the free ends of said pins extending into firm abutting engagement with said core to provide lateral support thereof.
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) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |