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US2639478A Expired / Lapsed US ⏱️ 0.0 years remaining

Process of preparing patterns

Assignee: United States Gypsum Co
•
Filing: 1949-12-16
•
Granted: 1953-05-26
•
Expires: 1969-12-16
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Abstract

No abstract record available.

Inventors

  • 👤 Brainard W Nies
  • 👤 Edward W Duffy

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 11:26
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/14; B; B22; B22C; B22C7/00; B22C7/02

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 108 words
THE PROCESS OF CASTING A SUBSTANTIALLY DIMENSIONALLY ACCURATE REPRODUCTION OF AN OBJECT FROM A HARDENABLE FLUID MATERIAL WHICH SHRINKS UPON HARDENING, COMPRISING FORMING A MOLD HAVING A CASTING CAVITY CONFORMING TO THE SHAPE OF THE OBJECT TO BE REPRODUCED, POURING AN AQUEOUS SLURRY OF A CALCINED GYPSUM PLASTER HAVINGG A SETTING EXPANSION OF AT LEAST ABOUT 0.65% INTO SAID CAVITY, PREMITTING SAID PLASTER HAVING TO EXPAND UPON SETTING TO FORM A PATTERN, FORMING A MOLD FROM SAID PATTERN, AND CASTING A HARDENABLE FLUID IN SAID MOLD, THE INCREASE IN SIZE OF SAID PATTERN OVER SAID OBJECT BEING SUBSTANTIALLY THE SAME AS THE SHRINKAGE OF SAID FLUID DURING HARDENING.
Claim 2
Dependent Claim 108 words
THE PROCESS OF CASTING A SUBSTANTIALLY DIMENSIONALLY ACCURATE REPRODUCTION OF AN OBJECT FROM A HARDENABLE FLUID MATERIAL WHICH SHRINKS UPON HARDENING, COMPRISING FORMING A MOLD HAVING A CASTING CAVITY CONFORMING TO THE SHAPE OF THE OBJECT TO BE REPRODUCED, POURING AN AQUEOUS SLURRY OF A CALCINED GYPSUM PLASTER HAVINGG A SETTING EXPANSION OF AT LEAST ABOUT 0.65% INTO SAID CAVITY, PREMITTING SAID PLASTER HAVING TO EXPAND UPON SETTING TO FORM A PATTERN, FORMING A MOLD FROM SAID PATTERN, AND CASTING A HARDENABLE FLUID IN SAID MOLD, THE INCREASE IN SIZE OF SAID PATTERN OVER SAID OBJECT BEING SUBSTANTIALLY THE SAME AS THE SHRINKAGE OF SAID FLUID DURING HARDENING.

References Cited (Backward Citations)

CA198973A Cited
US1508800A Cited
US910166A Cited
US980888A Cited
US1901054A Cited
US2118468A Cited
US2078199A Cited
US2078200A Cited
US2391855A Cited
US2396195A Cited
US2494403A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1956-05-25 1956-11-24 1957-05-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1960-05-25 1960-11-24 1961-05-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1964-05-25 1964-11-24 1965-05-26 $7700.00 Window Closed / Lapsed

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