Re: Hollow PP Capacitors...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-uswest-dot-net>" <bert.hickman-at-aquila-dot-net>

Terry,

Apparently, the folks at High Voltage Components, Inc. agree with you!
Here's a picture of one of their hollow 0.03 uF 30 kV pulse capacitors that
was originally part of a high power pulsed laser system:
http://www.aquila-dot-net/bert.hickman/photos/HVCAP2.jpg

The 7" long capacitor has an outer diameter of 5" and the hollow interior
is 1.75" in diameter. The laser tube actually goes through the center of
the capacitor! The cap is made to have very low inductance and high pulse
discharge current... just look at the massive copper end terminal. Although
the main reason for this style construction was primarily to minimize
inductance, it no doubt also aids in heat dissipation. 

Doesn't look like it's possible to patent the idea, though... :^)

Best regards,

-- Bert --
-- 
Bert Hickman
Stoneridge Engineering
Email:    bert.hickman-at-aquila-dot-net
Web Site: http://www.teslamania-dot-com

Tesla list wrote:
> 
> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
> 
<Big SNIP...>
> "I" would make them
> hollow so the cap is more of a tube.  Then the heat would not build up in
> the center and I think you could get far higher currents through them
> without overheating.  Most of the capacitance is in the outer layers anyway
> so making them hollow would not reduce the capacitance/volume that much.  I
> would not be surprised if you could get 4X the current through one.  Maybe
> Chris could mention this to his pals at CD ;-))  You need fancy stuff to
> make poly film/foil caps so it is not a home project...
> 
> Unlike tcp/ip DNS server network stuff, I do know a bunch about poly caps
> :-))  The hollow cap idea seems to me like a really promising thing to try.
>  Maybe it could be patented buy some big cap manufacturer and make them
> rich.  Of course, we could use them too.  If it were a big deal idea, I
> would not care about the patents and all that crap.  I just want the caps
> for my coil :-))
> 
> Cheers,
> 
>         Terry
>