US3961003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for making elongated Si and SiC structures
Assignee: Dow Silicones Corp
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Filing: 1974-02-04
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Granted: 1976-06-01
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Expires: 1994-02-04
Abstract
Abstract Method for making elongated structures such as furnace tubes having at least one flat side from vapor deposited silicon or silicon carbide using a graphite mandrel having a plurality of elongated edge-mated elements held in place by end collars to which an electrical power source is connected. Rectangular tubes can be sawed apart to produce flat plates if desired.
Inventors
- 👤 David L. Parsels
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:56
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/01; C04; C04B; C04B35/00; C04B35/515; C04B35/56; C04B35/565; C04B35/571; C23C16/22
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
180 words
A method of making a one-piece elongated structure of vapor deposited silicon or silicon carbide, said structure having at least one flat side in the direction of elongation, which method comprises Forming a graphite mandrel having an axis by forming mating surfaces on the edges of a plurality of elongated graphite elements having equal lengths and having end portions at each end thereof, said end portions being transverse to the edges having said mating surfaces, at least one of said elements being a flat slab all of the elements having an external surface facing away from the axis of the mandrel; placing the elements in the configuration of the structure desired with said mating surfaces in mated relationship, and securing the mated elements in mated position by a pair of collars surrounding and in intimate contact with the end portions of said mated elements, Heating of the graphite mandrel to the range of 1,000°-2,000°C. Depositing said silicon or silicon carbide on said external surface of said heated mandrel from the vapor phase, and Removing the mandrel from the deposited material.
Claim 2
Independent Claim
180 words
A method of making a one-piece elongated structure of vapor deposited silicon or silicon carbide, said structure having at least one flat side in the direction of elongation, which method comprises Forming a graphite mandrel having an axis by forming mating surfaces on the edges of a plurality of elongated graphite elements having equal lengths and having end portions at each end thereof, said end portions being transverse to the edges having said mating surfaces, at least one of said elements being a flat slab all of the elements having an external surface facing away from the axis of the mandrel; placing the elements in the configuration of the structure desired with said mating surfaces in mated relationship, and securing the mated elements in mated position by a pair of collars surrounding and in intimate contact with the end portions of said mated elements, Heating of the graphite mandrel to the range of 1,000°-2,000°C. Depositing said silicon or silicon carbide on said external surface of said heated mandrel from the vapor phase, and Removing the mandrel from the deposited material.
Claim 3
Dependent Claim
29 words
A method as defined in claim 1 wherein said collars are electrically conductive and said collars are connected to an electrical power source to cause heating of the mandrel.
Claim 4
Dependent Claim
42 words
A method as defined in claim 2 and further including forming corresponding tapers on the exterior surfaces of the ends of said elements and the interior surfaces of said collars whereby intimate electrical contact between the collar and said elements is assured.
Claim 5
Dependent Claim
101 words
Apparatus for forming one-piece elongated structures of vapor deposited silicon or silicon carbide comprising A graphite mandrel having a plurality of elongated graphite elements of equal lengths and having edge portions along the entire lengths thereof and having end portions transverse to said edge portions, at least one of said elements being a flat slab; said elements having mating surfaces at the edge portions thereof and being held together with said mating surfaces in mating relationship by a pair of collars surrounding and in intimate contact with the end portions of said mated elements, and Heating means for heating said mandrel.
Claim 6
Dependent Claim
101 words
Apparatus for forming one-piece elongated structures of vapor deposited silicon or silicon carbide comprising A graphite mandrel having a plurality of elongated graphite elements of equal lengths and having edge portions along the entire lengths thereof and having end portions transverse to said edge portions, at least one of said elements being a flat slab; said elements having mating surfaces at the edge portions thereof and being held together with said mating surfaces in mating relationship by a pair of collars surrounding and in intimate contact with the end portions of said mated elements, and Heating means for heating said mandrel.
Claim 7
Dependent Claim
25 words
Apparatus as defined in claim 4 wherein said collars are electrically conductive and said heating means includes an electrical power source connected across said collars.
Claim 8
Dependent Claim
46 words
Apparatus as defined in claim 5 wherein the exterior surfaces of the ends of said elements are tapered and the interior surfaces of said collars have a corresponding taper whereby press fitting of said collars onto said elements insures intimate contact between said collars and elements.
Claim 9
Dependent Claim
50 words
Apparatus as defined in claim 6 wherein each of said collars is provided with a tapered male portion extending in a direction opposite the portion holding said elements and a tapered electrical contact ring is fitted on said male portion, said electrical power source being connected to said contact ring.
Claim 10
Dependent Claim
20 words
Apparatus as defined in claim 6 wherein said elements are all rectangular slabs and said mandrel is of rectangular configuration.
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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) | 1979-06-01 | 1979-12-01 | 1980-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-01 | 1983-12-01 | 1984-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-01 | 1987-12-01 | 1988-06-01 | $7700.00 | Window Closed / Lapsed |