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US2749572A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of shaping thermoplastic sheets

Assignee: Van Brode Milling Co Inc
•
Filing: 1954-02-11
•
Granted: 1956-06-12
•
Expires: 1974-02-11
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Abstract

No abstract record available.

Inventors

  • 👤 Roger L Nowak

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 02:12
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/26; B29C51/30; B29C51/34; B29C51/42; B29C51/421; B29C51/422; Y; Y10; Y10S; Y10S220/00; Y10S220/12; Y10S264/00; Y10S264/50; Y10S264/78; Y10S425/00; Y10S425/039

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 151 words
THE METHOD OF SHAPING A THERMOPLASTIC SHEET INTO A DEEP-DRAWN CONTAINER HAVING AN OUTWARDLY EXTENDING CURLED TOP EDGE, WHICH CONSISTS IN CLAMPING SAID SHEET ACROSS A TOP CAVITY WHICH SLOPES TOWARD AND CONNECTS WITH A MOLD CAVITY AND HAS FORMED THEREIN AN ANNULAR GROOVE CONCENTRIC WITH AND AROUND THE MOUTH OF SAID MOLD CAVITY, SAID ANNULAR GROOVE BEING SEPARATED FROM SAID MOLD CAVITY BY A RIB THE TOP OF WHICH IS IN ALINEMENT WITH THE SLOPE OF SAID TOP CAVITY, SUBJECTING SAID SHEET TO NON-UNIFORM HEAT TO EFFECT DIFFERENTIAL PLASTICITY IN SAID SHEET, SAID HEAT BEING SO CONTROLLED THAT THE CONDITION OF GREATEST PLASTICITY OF SAID SHEET IS EFFECTED IN THOSE REGIONS THEREOF WHICH LIE OUTSIDE OF THE AREA OF SAID MOLD CAVITY BUT INCLUDE THE AREA OF SAID ANNULAR GROOVE, AND WITHDRAWING AIR FROM BOTH OF SAID CAVITIES WHEREBY SAID SHEET IS MADE TO ASSUME THE CONFORMATION OF SAID CAVITIES.
Claim 2
Independent Claim 151 words
THE METHOD OF SHAPING A THERMOPLASTIC SHEET INTO A DEEP-DRAWN CONTAINER HAVING AN OUTWARDLY EXTENDING CURLED TOP EDGE, WHICH CONSISTS IN CLAMPING SAID SHEET ACROSS A TOP CAVITY WHICH SLOPES TOWARD AND CONNECTS WITH A MOLD CAVITY AND HAS FORMED THEREIN AN ANNULAR GROOVE CONCENTRIC WITH AND AROUND THE MOUTH OF SAID MOLD CAVITY, SAID ANNULAR GROOVE BEING SEPARATED FROM SAID MOLD CAVITY BY A RIB THE TOP OF WHICH IS IN ALINEMENT WITH THE SLOPE OF SAID TOP CAVITY, SUBJECTING SAID SHEET TO NON-UNIFORM HEAT TO EFFECT DIFFERENTIAL PLASTICITY IN SAID SHEET, SAID HEAT BEING SO CONTROLLED THAT THE CONDITION OF GREATEST PLASTICITY OF SAID SHEET IS EFFECTED IN THOSE REGIONS THEREOF WHICH LIE OUTSIDE OF THE AREA OF SAID MOLD CAVITY BUT INCLUDE THE AREA OF SAID ANNULAR GROOVE, AND WITHDRAWING AIR FROM BOTH OF SAID CAVITIES WHEREBY SAID SHEET IS MADE TO ASSUME THE CONFORMATION OF SAID CAVITIES.

References Cited (Backward Citations)

US1415018A Cited
US1904268A Cited
US2377946A Cited
US2444420A Cited
US2425390A Cited
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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) 1959-06-12 1959-12-12 1960-06-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1963-06-12 1963-12-12 1964-06-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1967-06-12 1967-12-12 1968-06-12 $7700.00 Window Closed / Lapsed

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