Patent US3616840A successfully refreshed from Google Patents.
US3616840A
Expired / Lapsed
US
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Method of making multilayer shell molds
Assignee: Individual
•
Filing: 1969-01-08
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Granted: 1971-11-02
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Expires: 1989-01-08
Abstract
Abstract Shell molds are prepared by applying to a pattern a slurry containing sodium or potassium silicate, removing the pattern from the slurry and coating it with refractory material, and then applying a phosphorus-containing gelling agent. The cycle is then repeated until the desired number of layers are built up on the pattern.
Inventors
- 👤 Adam Dunlop
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:17
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/165
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
14 words
The method as defined in claim 1 wherein said phosphorus compound is phosphorus pentoxide.
Claim 2
Dependent Claim
20 words
The method as defined in claim 2 wherein said refractory powder is applied to said pattern from a fluidized bed.
Claim 3
Dependent Claim
33 words
The method as defined in claim 2 wherein said pattern is a core box and said silicate refractory material and liquid gelling agent is sequentially poured in and out of said core box.
Claim 4
Dependent Claim
14 words
The method as defined in claim 2 wherein said organic carrier is an alcohol.
Claim 5
Dependent Claim
13 words
The process as defined in claim 6 wherein said alcohol is ethyl alcohol.
Claim 6
Dependent Claim
15 words
The method as defined in claim 2 wherein said gelling agent includes hydrolyzed alkyl silicate.
Claim 7
Dependent Claim
20 words
The method as defined in claim 2 wherein said pattern is initially coated with a slurry comprising hydrolyzed alkyl silicate.
Claim 8
Dependent Claim
38 words
The method as defined in claim 2 wherein said pattern is removed from the thus-formed layers of refractory material by heating said pattern to a temperature sufficient to melt said pattern, said temperature being less than 1,900* F.
Claim 9
Independent Claim
90 words
A method of manufacturing multilayer shell molds which comprises the steps of applying to a pattern an alkaline slurry containing water and at least one compound selected from the group consisting of sodium silicate and potassium silicate, then coating said pattern with refractory material, applying to the thus coated patteRn a liquid gelling agent for said slurry, said gelling agent being substantially free of water and comprising phosphorus trichloride and an organic carrier, and then substantially immediately repeating said steps to build up a plurality of layers of refractory material.
Claim 10
Dependent Claim
20 words
The method as defined in claim 10 wherein said refractory material is applied to said pattern from a fluidized bed.
Claim 11
Dependent Claim
33 words
The method as defined in claim 10 wherein said pattern is a core box and said silicate refractory material and liquid gelling agent is sequentially poured in and out of said core box.
Claim 12
Dependent Claim
14 words
The method as defined in claim 10 wherein said organic carrier is an alcohol.
Claim 13
Dependent Claim
13 words
The method as defined in claim 13 wherein said alcohol is ethyl alcohol.
Claim 14
Dependent Claim
15 words
The method as defined in claim 10 wherein said gelling agent includes hydrolyzed alkyl silicate.
Claim 15
Dependent Claim
20 words
The method as defined in claim 10 wherein said pattern is initially coated with a slurry comprising hydrolyzed alkyl silicate.
Claim 16
Dependent Claim
39 words
The method as defined in claim 10 wherein said pattern is removed from the thus formed layers of refractory material by heating said pattern to a temperature sufficient to melt said pattern, said temperature being less than 1,900* F.
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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) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |