US3680625A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat reflector
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1970-11-12
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Granted: 1972-08-01
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Expires: 1990-11-12
Abstract
Abstract Method and apparatus for producing columnar castings by precision investment casting techniques, wherein a refractory reflector is positioned in the furnace behind the molds contained therein to make it possible to control the unidirectional temperature gradient more closely and provide more pieces per mold.
Inventors
- 👤 Frank J Hein
- 👤 Donald G Fleck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:16
CPC Classifications
C; C30; C30B; C30B11/00; C30B11/002; B; B22; B22D; B22D27/00; B22D27/04; B22D27/045; C30B11/003
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
86 words
An apparatus for precision casting comprising a furnace wall, an induction heating coil disposed around said wall, a susceptor disposed inside said wall and adjacent thereto, a casting mold assembly comprising a plurality of circumferentially spaced ceramic molds enclosed by said wall, a common feed means disposed centrally of said molds for introducing molten metal radially into each of said molds, and refractory reflector means separate from said ceramic molds disposed in closely spaced relation to said molds on the sides thereof opposite to said susceptor.
Claim 2
Independent Claim
86 words
An apparatus for precision casting comprising a furnace wall, an induction heating coil disposed around said wall, a susceptor disposed inside said wall and adjacent thereto, a casting mold assembly comprising a plurality of circumferentially spaced ceramic molds enclosed by said wall, a common feed means disposed centrally of said molds for introducing molten metal radially into each of said molds, and refractory reflector means separate from said ceramic molds disposed in closely spaced relation to said molds on the sides thereof opposite to said susceptor.
Claim 3
Dependent Claim
14 words
The apparatus of claim 1 in which said reflector is integral with said mold.
Claim 4
Dependent Claim
18 words
The apparatus of claim 1 which includes a surface of high heat conductivity upon which said molds rest.
Claim 5
Dependent Claim
22 words
The apparatus of claim 1 in which said reflector means is in the form of an annulus surrounding said common feed means.
Claim 6
Independent Claim
124 words
The method of producing columnar castings which comprises positioning a plurality of spaced, open-ended ceramic molds on a highly heat conductive surface within a furnace including a susceptor which radiates heat at said molds, preheating said molds to a temperature above the solidus temperature of the metal to be cast, positioning a ceramic reflector inwardly of said molds so that such molds are disposed between said reflector and said susceptor, said reflector being separate from said ceramic molds and being positioned to reflect heat radiated from said susceptor to portions of said molds which would otherwise be screened from such radiated heat, pouring molten metal into said molds, and providing a unidirectional temperature gradient within said molds during the solidification of the metal therein.
Claim 7
Independent Claim
124 words
The method of producing columnar castings which comprises positioning a plurality of spaced, open-ended ceramic molds on a highly heat conductive surface within a furnace including a susceptor which radiates heat at said molds, preheating said molds to a temperature above the solidus temperature of the metal to be cast, positioning a ceramic reflector inwardly of said molds so that such molds are disposed between said reflector and said susceptor, said reflector being separate from said ceramic molds and being positioned to reflect heat radiated from said susceptor to portions of said molds which would otherwise be screened from such radiated heat, pouring molten metal into said molds, and providing a unidirectional temperature gradient within said molds during the solidification of the metal therein.
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) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |