DC Injection Braking - Find the patent!

Discussion in 'Electronics Resources' started by xylstra, Jul 21, 2015.

  1. xylstra

    Thread Starter New Member

    Jul 21, 2015
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    Simple DC Injection Braking Circuit: Please have a look at the circuit diagram attached. I am writing a technical article and wish to authoritatively quote the correct patent number for this circuit. So far my searches have eluded me. Does anyone know of it or else can provide more information as to the technique's origins (i.e. names, dates. etc). I suspect it would have to be around the 1950's or before. untitled.png
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Are you sure that is under patent, that circuit has been around in general use for some time.
    Max.
     
  3. xylstra

    Thread Starter New Member

    Jul 21, 2015
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    Hi Max, Please, tell me MORE, MORE!! Seriously, what do you know of its history? (I would be highly surprised if there was no patent) Kind Regards.
     
  4. DickCappels

    Moderator

    Aug 21, 2008
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    Have you checked the prior art cited in these U.S. patents?

    2,413,070 Reeves _____________ _.. Dec. 24, 1946

    2,606,312 Rogers _____________ .._ Aug. 5, 1952

    2,821,639 Bright et \al. _________ __ Jan. 28, 1958

    1,976,562 Janisch ___________ __ Oct. 9, 1934

    2,167,530 Schneider ________ __ July 25, 1939

    2,264,333 Satterlee _________ __ Dec. 2, 1941
     
  5. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    5,776
    1,103
    If the patent dates back to the 50's it has expired and is no longer enforceable.
     
  6. alfacliff

    Well-Known Member

    Dec 13, 2013
    2,449
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    we still had some grinders around here with tubes to time the dc injection. if that gives you any idea of how old the patent might be.
     
  7. Glenn Holland

    Member

    Dec 26, 2014
    353
    110
    Looks like a simple DC injection circuit for producing dynamic braking in an induction motor.

    The patents on this arrangement were probably issued during the earlier days of electricity after Nicola Tesla introduced AC power.
     
  8. xylstra

    Thread Starter New Member

    Jul 21, 2015
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  9. xylstra

    Thread Starter New Member

    Jul 21, 2015
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    Hi Dick, Thanks for taking the time to reply. Unfortunately none of your quoted patents are of any use since they relate to DC motors, not AC Induction Motors. I'm still hopeful someone will deliver the goods!
     
  10. xylstra

    Thread Starter New Member

    Jul 21, 2015
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    I know all that! What I want to know is the patent number! Someone must know......
     
  11. xylstra

    Thread Starter New Member

    Jul 21, 2015
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    It might very well be simple, but it's actually very subtle. Think about it....!
     
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