Patent US3593775A successfully refreshed from Google Patents.
US3593775A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat transfer means in inviscid melt spinning apparatus
Assignee: Monsanto Co
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Filing: 1969-04-11
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Granted: 1971-07-20
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Expires: 1989-04-11
Abstract
Abstract The severe thermal gradients which are ordinarily present in the base of a crucible employed in high-temperature spinning operations are significantly reduced through utilization of a thermally anisotropic shelf. The bottom surface of the crucible base is positioned substantially parallel with the plane of high thermal conductivity of the shelf and in thermal conduction contact therewith. Concurrently, the crucible extrusion opening and an aperture within the shelf are aligned substantially coaxially. A means is employed for heating the outer periphery regions of the shelf, causing a heat flow toward the aperture. The substantially constant temperature along the thermal plane of the shelf and at the region of the shelf adjacent to the aperture therein preclude the formation of significant lateral thermal gradients which are responsible for fracture of the crucible base. Precipitation buildup near or in the extrusion hole is also significantly reduced by keeping the extrusion hole at least as hot as the surrounding melt.
Inventors
- 👤 Wilbur J Privott Jr
- 👤 Wallace C Lawrence
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:03
CPC Classifications
B; B22; B22D; B22D11/00; B22D11/005
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
96 words
In an apparatus including a crucible assembly for spinning an inviscid melt as a free stream, the combination of: a member having an extrusion opening therein; an anisotropic shelf having an aperture which is positioned substantially coaxial with said extrusion opening, said shelf having the plane of high thermal conductivity extending from the periphery region of said shelf to said aperture; heating means for heating the periphery region of said shelf; and wherein the region of said shelf adjacent the aperture is in thermal conduction contact with the region of said member adjacent said extrusion opening.
Claim 2
Dependent Claim
96 words
In an apparatus including a crucible assembly for spinning an inviscid melt as a free stream, the combination of: a member having an extrusion opening therein; an anisotropic shelf having an aperture which is positioned substantially coaxial with said extrusion opening, said shelf having the plane of high thermal conductivity extending from the periphery region of said shelf to said aperture; heating means for heating the periphery region of said shelf; and wherein the region of said shelf adjacent the aperture is in thermal conduction contact with the region of said member adjacent said extrusion opening.
Claim 3
Dependent Claim
11 words
In the apparatus of claim 1, said shelf comprising pyrolytic graphite.
Claim 4
Dependent Claim
48 words
In the apparatus of claim 1, said member being the base of a crucible for containing the inviscid melt, said thermally anisotropic shelf physically contacting essentially the entire bottom surface of said crucible base and having the plane of high thermal conductivity substantially parallel to said bottom surface.
Claim 5
Dependent Claim
54 words
In the apparatus of claim 3, said crucible further comprising an upright wall member separate from and supported by said base, said upright wall member and said base defining a container for the low viscosity melt and having lapped surfaces in the area of mutual contact to prevent leakage of the inviscid melt therebetween.
Claim 6
Dependent Claim
23 words
In the apparatus of claim 4, said crucible being made of ceramic material at least in the area of contact with the melt.
Claim 7
Dependent Claim
23 words
In the apparatus of claim 5, said crucible being made from a material selected from the group consisting of alumina, beryllia, and zirconia.
Claim 8
Dependent Claim
30 words
In the apparatus of claim 1, the region of said member adjacent said extrusion opening and the region of said shelf adjacent said aperture mutually contacting a thermal-conducting second member.
Claim 9
Dependent Claim
22 words
In the apparatus of claim 1, said shelf and said member being substantially cylindrical in shape with said shelf circumscribing said member.
Claim 10
Dependent Claim
51 words
In the apparatus of claim 1, a crucible, a susceptor encircling said crucible, said heating means being an inductive coil in a helical configuration about said susceptor and the outer periphery region of said shelf, said inductive coil further having turns spaced closer together adjacent said shelf than adjacent said susceptor.
Claim 11
Dependent Claim
42 words
In the apparatus of claim 1, said shelf being provided with an essentially annular slot in the lower surface thereof which is substantially coaxial with said aperture and normal to said a-b plane thereby preventing the transfer of heat across said slot.
Claim 12
Dependent Claim
55 words
In the apparatus of claim 1, the upper periphery region of said shelf extending laterally beyond the lower periphery region thereof and said heating means comprising an inductor coil positioned so as to have the electromagnetic flux lines intersect the upper periphery region of said shelf but not the lower periphery region of said shelf.
Claim 13
Dependent Claim
148 words
In the apparatus of claim 1, said heating means comprising an inductive coil and an electromagnetic flux concentrator positioned adjacent the upper periphery region of said shelf so as to increase the density of flux lines intersecting said upper periphery region. 13, In the apparatus of claim 12, said flux concentrator further comprising a washerlike conductor member substantially encircling the upper periphery region of said shelf, said conductor member having a gap extending therethrough, and a plurality of turns of said coil positioned along one surface of said conductor member in a substantially coplanar arrangement, the inner turn of said coil being mounted on and in electrical contact with said conductor member from one side of said gap to the other side, the outer turns of said coil being electrically insulated from said conductor member and being coupled to said conductor member when said coil is electrically energized.
Claim 14
Dependent Claim
140 words
In a spinning apparatus for spinning an inviscid melt through an extrusion opening in a member wherein the portion of said member containing said extrusion opening is in thermal-conducting contact with a thermally anisotropic shelf having an aperture substantially coaxial with said extrusion opening. heating means for supplying heat to said extrusion opening including an electromagnetic flux concentrator, said flux concentrator comprising a washerlike conductor member substantially encircling the upper periphery region of said shelf and having a gap therethrough and a plurality of turns of an inductor coil positioned along one surface of said conductor member in a substantially coplanar arrangement, said turns being coupled to said conductor member when said coil is electrically energized wherein said thermally anisotropic shelf has its plane of high thermal conductivity extending in a direction from said flux concentrator to said extrusion opening.
Claim 15
Dependent Claim
140 words
In a spinning apparatus for spinning an inviscid melt through an extrusion opening in a member wherein the portion of said member containing said extrusion opening is in thermal-conducting contact with a thermally anisotropic shelf having an aperture substantially coaxial with said extrusion opening. heating means for supplying heat to said extrusion opening including an electromagnetic flux concentrator, said flux concentrator comprising a washerlike conductor member substantially encircling the upper periphery region of said shelf and having a gap therethrough and a plurality of turns of an inductor coil positioned along one surface of said conductor member in a substantially coplanar arrangement, said turns being coupled to said conductor member when said coil is electrically energized wherein said thermally anisotropic shelf has its plane of high thermal conductivity extending in a direction from said flux concentrator to said extrusion opening.
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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) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |