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US1921750A Expired / Lapsed US ⏱️ 0.0 years remaining

Centrifugal separator for straining pulpy material, such as wood pulp, cellulose, paper pulp, and the like

Assignee: Individual
•
Filing: 1932-03-24
•
Granted: 1933-08-08
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Expires: 1952-03-24
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Abstract

No abstract record available.

Inventors

  • 👤 Heinrich Richard
  • 👤 Zipprian Hans

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 16:03
CPC Classifications
D; D21; D21D; D21D5/00; D21D5/02; D21D5/023; D21D5/026

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

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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) 1936-08-07 1937-02-06 1937-08-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1940-08-07 1941-02-06 1941-08-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1944-08-07 1945-02-06 1945-08-08 $7700.00 Window Closed / Lapsed

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