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Piston Air Bypass

Loose pistons.
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(+3, -1)
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Hope I can describe this right.

I envsion the crankcase of the motor having a filtered intake to take in air. This is in place of intake valves.

The pistons mount at the top of the connecting rods incorporate vertical pill shaped connecting holes instead of a round hole. The connecting rod end would be of a slightly smaller diamater on a bearing to roll around the pill shape, removing impact that would destroy the motor.

The pistons are also two parts, the middle is a tapered valve. When the piston pushes up, the force keeps the two parts closed, but when the piston pulls down for the intake cycle, the force opens the piston valve,and air passes into the cylinder, closing at the bottom, ready for the compressions stroke. Direct injection would also have to be used.

This could decrease by half the number of moving parts in the valve train, double the space available for exhaust valves, increase the available revs of the motor, removal of intake plenum, and the air running through the crankcase would cool the oil.

Giblet, Jul 18 2007

Gnome rotary http://www.keveney.com/gnome.html
Take a look at the valve arrangement. [Freefall, Jul 18 2007]


       My idea seems very similar, except in an inline configuration.
Giblet, Jul 18 2007

       I don't understand the second paragraph.   

       What shape of pill are you thinking of?
BJS, Jul 19 2007

       if a circle was split in two, and moved apart, same shape as a capsule.
Giblet, Jul 19 2007

       What is going to keep the power stroke from simply forcing open the "piston valve"?
Galbinus_Caeli, Jul 19 2007

       At first I thought you were suggesting non-circular pistons. Honda tried that and gave up on it.   

       So, do I understand this to be working as a two stroke, and thus each crank throw has to be sealed from the others, so the crankcase can pressurize?   

       I think I get it: the piston's wrist pin is also acting as a cam, so that as it rotates slightly from the conrod turning it, it actuates a valve for air intake? Not as simplistically as that, of course: the wrist pin would merely oscillate back and forth. You'll need a nonsymmetrical shape, I think.   

       I want to bun it, but I need better understanding.
elhigh, Jul 19 2007

       OK stroke 1 of 4, intake. The force of the connecting rod pulling down opens the piston, and air passes in.   

       2 of 4, compression. Pushing up closes the piston valve while atomized fuel is direct injected.   

       3 of 4, combustion, the explosion in the cylinder would be greater then the force of the piston moving down, keeping it closed, hopefully answering your question.   

       4 of 4, exhaust, the piston remains closed on the upstroke.   

       The wrist pin as I see it, would roll around the pill shaped hole, instead of banging around inside of it.   

       This could also be accomplished by a sprung valve after thinking about it some more. But I dont want the valve fighting the compression, reducing efficiency.
Giblet, Jul 20 2007

       This is a more complicated arrangement than a conventional reed valve two stroke...
madness, Jul 20 2007

       What if my shoe fell off?   

       Anything can break, or happen.   

       It might be a more complicated 2 stroke, except it's a 4 stroke.   

       Is there a 4 stroke reed valve engine?
Giblet, Jul 20 2007

       I don't see what's so confusing about this. I understood it perfectly the first time I read it. And I like it.
notexactly, Apr 22 2018


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