Plasma Jet Ignition

[Jeffrey T. Birt]

This plasma jet thread has been interesting.  I repair welders and plasma
cutting machines for a living so perhaps I can shed some light on the
subject.  By no mean do I profess to be an expert though.

First the TIG welder question.  Typically this is arc starting capability
is called  'High Frequency' in the welding world.  It is really very
simple.  One of the welding leads passes through the center of an air core
transformer.  A high voltage, high frequency signal is 'superimposed'
(transformer coupled actually) on the weld voltage.  This 'high freq.'
lets you establish the arc without touching the work piece.

As for the plasma thing.  The initial high voltage low current arc is
called the pilot arc.  It sort of serves the same purpose as in the TIG
application.  As to the application to a plasma gas ignition?  I don't
know.  Just remember an arc exist point to point, i.e. across a gap.

Jeff Birt




> bob at bobthecomputerguy.com (Robert Harris) wrote:
>
> >Re-reading my Heywood and have become re-in-love with the concept of
> >plasma jet ignition.   Essentially, a normal CD ignition fires the
> >plug in a cavity connected to the main chamber by an orifice.  Once
> >the arc is established, a second low voltage high current capacitive
> >discharge is routed into the arc.
>
> Hey - I like the sound of THAT.  Did someone get this working?
>
> This reminds me of the arc stabilizers you find on TIG welders - a high
> frequencyt current starts the pilot plasma/arc which then allows the
> main welding current to flow on through...
>
> Keep me advised as to your success! :)
> -Bill
>
> ______________________________________________________
> Get Your Private, Free Email at http://www.hotmail.com