Tesla patent 381,970 & TPU

[sparks]

    I think the magnets bias the reluctance of the coil that is below them.  Any change in this core reluctance gets amplified by the coil current.  Saturable core reactor of sorts. 

    Along the same lines I don't believe SM used any bailing wire because as pointed out iron is way to slow.  I believe he was using aluminum as the magnetic field pickup.

[vince]

Hi Guys:

Can anyone answer a question for me about wire cores?  To make an iron core out of bailing wire, or any steel wire with or without insulation would you wind the wire around a form as one continuous loop like a coil or would you use individual pieces of wire that wind around the circumference once and join up with their own starting point? It seems that 1 continuous loop would have only 1 flux path especially with insulated wire .  With laminated cores the individual plates meet end to end where they join.

Thanks in advance
Vince

[zerotensor]

Hi Guys:

Can anyone answer a question for me about wire cores?  To make an iron core out of bailing wire, or any steel wire with or without insulation would you wind the wire around a form as one continuous loop like a coil or would you use individual pieces of wire that wind around the circumference once and join up with their own starting point? It seems that 1 continuous loop would have only 1 flux path especially with insulated wire .  With laminated cores the individual plates meet end to end where they join.

@vince:
Personally, I would favor using one continuous length of insulated iron wire.  This way, you could tap the ends of the wire and extract any current or signal that may be induced therein.  Alternately, you could drive the core wire with a signal, possibly allowing real-time control of the core's magnetic properties.  Your concern about there only being one flux path is not warranted; the magnetic flux through any cross-sectional slice of the core material will be nearly the same whether you use a looped continuous strand or many individual strands bundled together, so long as the total mass and surface area of the core material remains the same.