Patent US2820268A successfully refreshed from Google Patents.
US2820268A
Expired / Lapsed
US
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Method of making shell molds with thin core
Assignee: Individual
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Filing: 1955-09-16
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Granted: 1958-01-21
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Expires: 1975-09-16
Abstract
No abstract record available.
Inventors
- 👤 Everard F Kohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:23
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/12; B22C9/126; B22C9/02; B22C9/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
152 words
THE METHOD OF PREPARING A POROUS SELF-SUPPORTING SHELL MOLD IN THE FORM OF A POROUS THIN SHELL LAYER FORMED OVER THE EXPOSED SURFACES OF A FROZEN MERCURY PATTERN OF AN OBJECTED TO BE CAST WITH METAL OF HIGH MELTING TEMPERATURE, WHICH METHOD COMPRISES THE PROCEDURE OF PROVIDING A FROZEN MERCURY CASTING PATTERN HAVING SPACED PATTERN WALL PORTIONS UNITED BY AN INTERMEDIATE PATTERN WALL PORTION, PREPARING A LIQUID SLURRY-LIKE INVESTMENT COMPOSITION WHICH WILL ADHERE TO SAID PATTERN SURFACES WHEN APPLIED THERETO AS A COATING STRATUM AT VERY LOW TEMPERATURS BELOW THE FREEZING TEMPERATURE OF SAID PATTERN MATERIAL WHICH INVESTMENT COMPOSITION COMPRISES REFRACTORY PARTICLE MATERIAL CONSTITUTING A PREDOMINANT AMOUNT OF THE NORMALLY SOLID COMPOSITION INGREDIENTS APPLIED TO FORM SAID SHELL LAYER, A LOW REMPERATURE SYNTHETIC ORGANIC RESINOUS BINDER FOR THE REFRACTORY MATERIAL THAT IS ADHERENT TO SAID PATTERN AND WHICH IS EFFECTIVE IN BINDING AND IS PRESENT IN AN AMOUNT SUFFICIENT TO BIND THE
Claim 2
Independent Claim
152 words
THE METHOD OF PREPARING A POROUS SELF-SUPPORTING SHELL MOLD IN THE FORM OF A POROUS THIN SHELL LAYER FORMED OVER THE EXPOSED SURFACES OF A FROZEN MERCURY PATTERN OF AN OBJECTED TO BE CAST WITH METAL OF HIGH MELTING TEMPERATURE, WHICH METHOD COMPRISES THE PROCEDURE OF PROVIDING A FROZEN MERCURY CASTING PATTERN HAVING SPACED PATTERN WALL PORTIONS UNITED BY AN INTERMEDIATE PATTERN WALL PORTION, PREPARING A LIQUID SLURRY-LIKE INVESTMENT COMPOSITION WHICH WILL ADHERE TO SAID PATTERN SURFACES WHEN APPLIED THERETO AS A COATING STRATUM AT VERY LOW TEMPERATURS BELOW THE FREEZING TEMPERATURE OF SAID PATTERN MATERIAL WHICH INVESTMENT COMPOSITION COMPRISES REFRACTORY PARTICLE MATERIAL CONSTITUTING A PREDOMINANT AMOUNT OF THE NORMALLY SOLID COMPOSITION INGREDIENTS APPLIED TO FORM SAID SHELL LAYER, A LOW REMPERATURE SYNTHETIC ORGANIC RESINOUS BINDER FOR THE REFRACTORY MATERIAL THAT IS ADHERENT TO SAID PATTERN AND WHICH IS EFFECTIVE IN BINDING AND IS PRESENT IN AN AMOUNT SUFFICIENT TO BIND THE
References Cited (Backward Citations)
GB585665A
Cited
US2682692A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |