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Free piston accelerator

Seems to be a two stroke
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Have seen ball bearing pistons, rotary engines and induction, think they are neat so will use them.

Take one ball bearing and mount it in a circular tube so that is can roll freely. Add (reed) induction valves and carburetors at even intervals along the tube. Add compression and exhaust valves (at the same intervals) to create inline cylinders arranged end to end around the tube.

Add an induction coil around the tube and create small cavity where a spark plug can be mounted directly before each compression valve.

To start the engine apply current to the coil, inducing motion in the ball bearing and drawing fresh charge into the tube through the carburetors after the ball bearing and providing compression (against the compression valves) before the ball bearing.

As the ball bearing reaches a compression valve the fresh charge is forced into the spark plug cavity where it is ignited. The compression valve opens allowing the ball bearing to continue its progress helped along by the expanding gases behind it.

The exhaust valves open and the spent charge is forced from the tube (and new charge is draw through the induction valves).

Once the engine is started draw current from the same coil used to start it...

madness, Jul 05 2004

real hybrid http://www.halfbake...dea/Hybrid_20Engine
[madness, Oct 05 2004, last modified Oct 17 2004]

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       I thought first that this was a steel ball moving up and down between the two ignition ends in a closed cylinder.
FarmerJohn, Jul 05 2004
  

       Not half bad you know. I had a mad uncle who dedicated his life to rotary engines, and he found getting the power out was a huge problem. I like the induction solution, though I'm not sure what the efficiency would be like.
wagster, Jul 05 2004
  

       Could we have a description of how the compression valve works?   

       ..because gas sealing is often a weak point in such engines; if you can overcome that then this looks great: effectively a 'one-stroke', with very high potential power output.   

       You'd need two or more ball-bearing pistons spaced around the ring to provide good balance (using the induction coils to maintain relative positions).
philmckraken, Jul 05 2004
  

       The compression valve is the difficult part. The ideal valve will operate as follows.   

       1) It will be closed until the ball bearing creates satisfactory compression   

       2) As the valve opens the ball bearing will be allowed to carry on arround the tube. It will close behind the ball bearing and the new charge it has just created.   

       3) It will ensure that the compressed charge is now behind the ball bearing.   

       It seems to operate a bit like a revolving door. Two people can enter and come out in the reverse order without two much fuss.   

       There can also now be as many ball bearings traversing the tube as there are valves. This will provide the balance philmckraken is after...
madness, Jul 06 2004
  
      
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