Re: Rotory Static Gap

["Barton B. Anderson" <tesla123-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi Weazle, 

I thought about this a couple months ago while working with a program
contemplating RSG's and static gaps (cap voltage vs. timing). Since the disk
edge would tend to be the area that would want to conduct, it would be better
to use 2 stationary electrodes placed front and center of the flat surface of
the spinning disk, perferably sphere shaped and relatively large to increase
the ROC. It will be a static gap (voltage controlled) with a lot of heat
handling capability. We would be limited to materials to use (tungsten is out),
but it should still stay cool and may be a method where a high powered coil
(say 10kva) could use a static gap. I'm not real sure about that, it would need
to be tried first (maybe it already has). 

Anyway, I won't be building one soon, but sure would like to hear of someone
doing it (hint hint). The difficulty would be cutting a circular disk or
finding something suitable. Also, the conductive disk must be isolated from the
motor. This could prove difficult, but the best method I can think of is to
attach a circular ring to a G10 disk (say for a 12 inch G10 disk, a 3 inch ring
surface would allow 6 inch center). It would probalby be wise to machine the
disk ring for concentricity, balance, etc... 

Bart 

Tesla list wrote: 
>
> Original poster: "J. B. Weazle McCreath" <weazle-at-hurontel.on.ca> 
>
> Hello Coilers, 
>
> An electrical engineer friend loaned me an old book on high voltage 
> gear ranging from BIG induction coils to "medical" Tesla coils. 
> One of the things discussed was a rotory static gap which uses a 
> pair of counter rotating disks spaced the desired gap apart at 
> their edges.  Picture a pair of meshed gears, then grind off 
> the teeth, and you'll have the idea. 
>
> This style of gap would have no specific break rate as in a true 
> SRSG, but it does have an advantage of continuously presenting a 
> fresh surface for the arc to jump, and with much more mass than 
> conventional fixed gaps, it would run cooler as well.  Perhaps 
> the mechanics of insulating the disks from the shafts and the 
> drive train would negate any advantage, but I thought you might 
> find the idea interesting at least. 
>
> J.B. Weazle McCreath, VE3EAR      Web:    www.solwind.on.ca 
> c/o Solwind Enerco Inc.,          E-mail: weazle-at-solwind.on.ca 
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