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US3531704A Expired / Lapsed US ⏱️ 0.0 years remaining

Speed control system for dc motors

Assignee: Sony Corp
•
Filing: 1966-11-25
•
Granted: 1970-09-29
•
Expires: 1986-11-25
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Abstract

No abstract record available.

Inventors

  • 👤 Saburo Uemura
  • 👤 Toshiro Nishikawa
  • 👤 Yasuo Umezawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 14:52
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/2805; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/916

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US2881379A Cited
US3059163A Cited
US3234447A Cited
US3390316A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1973-09-28 1974-03-30 1974-09-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1977-09-28 1978-03-30 1978-09-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1981-09-28 1982-03-30 1982-09-29 $7700.00 Window Closed / Lapsed

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