Plasma Jet Ignition

Robert Harris bob at bobthecomputerguy.com
Thu Feb 25 14:49:32 GMT 1999


Two Parts to the Plasma Jet Ignition.  

First part is that the spark is developed in a small - according to patents
about 1 or 2 cc - pre chamber that allows it to develop and then fire a much
larger "Jet" into the main chamber.  Without this pre chamber, it simply
becomes a warmer ignition and loses most - if not all - its benefits.

Second is pumping as much energy as possible into the plasma discharge phase.

Interestingly enough, Rail Gun technology has been miniaturized for this
purpose.  

Patent 4,487,192 references SAE Paper "Design of a Plasma Jet Ignition System
for Automotive Applications"   SAE 776355 of 1977.  It describes the use of a
10 to 100 picofarad capacitor in parallel with an auxiliary spark gap and
another firing gap - confined within a plasma chamber.


  To HV Ignition system
     |
     +------------------------------------+
     |                                      |
    v                                      |
        (Auxiliary Gap)             |
    ^                                     |
    |                                  ---------
    |                                  ---------
   v                                      |
      ( Plug Gap )                  |
   ^                                      |
   |---------------------------------------+
 ----
  --
  -

The auxiliary gap exists solely to increase the break over voltage by about
20KV - thus raising the normal firing voltage to about ~ 40 k.   Higher break
over voltage results in faster discharge into the plug and chamber.

The small capacitor is initially seen by the ignition energy source as a short
and as a result, all of the ignition energy is diverted into the capacitor.

When the capacitor charges above the break over voltage of the combined
auxiliary gap and primary plug gap, the two gaps conduct and the electrical
conductance approaches infinity. 

The normal remaining ignition energy is dumped into the plug + all of the
stored energy in the external capacitor.   Since the cap is very close to the
plug or built in, there is very little inductance in the circuit, so the
auxiliary cap dumps extremely fast.

With this design and an associated pre chamber, the inventor states that only
about 100 mj is required to create the Plasma Jet - well within the reach of
higher end CD ignition systems.

Another patent refers to the use of a metal hydrate "pill" in the chamber to
seed the Plasma with free hydrogen.  Since hydrogen radicals penetrates about
5 times further into the main charge at the highest temperature, this nicely
enhances the blast.  Claims pill would be good for 10 million firings.
Replace about once a year.

Other patents refer to pumping and shaping the plasma with lasers and
electromagnetic energy.

Do not enter "Plasma Jet" into the IBM patent search engine if you are
paranoid that 666 Pennsylvania Avenue is out to eliminate your second
amendment rights and are desperately searching for a replacement for gun
powder.   Much of the plasma research has "details unavailable - government
held rights" attached and or is associated with former star wars technology.
THEY are watching your every access.  You are impotent.  But if everyone
started looking up plasma stuff, they'd become paranoid.  

1963 Ford C-600 Prison Bus Conversion "Home"
1971 Lincoln Continental 460 "Christine"
1972 "Whale" Mustang awaiting transplant
1978 Dodge Long Bed Peeek Up "Bundymobile"

Habaneros - not just for breakfast anymore



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