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Posted: Tue Jun 23, 2009 2:24 am
by sniper hero
http://www.spudfiles.com/forums/hammer- ... 17843.html

I made this valve already for a pneumatic :D

Posted: Tue Jun 23, 2009 9:19 am
by daccel
Could theoretically work, I think the problems would be balancing hammer strength to get the correct burst of fuel. Also, if I'm understanding correctly, the piston would be balanced due to stepped design, but pressures would still be unequal. So when dumped to chamber, the fuel wouldn't necessarily flow in, or not completely if the air is higher pressure. It would need to be dumped first?

If you regulated the fuel pressure and just used a spool (I think that's what it's called) valve instead of hammer, it would work but that defeats the goal of eliminating the regulator, and is more what Tech was talking about.

But I do like all this talk, has helped me already! I think I may borrow the tracking regulator idea, because it will be more compact than the 'compact regulator' I purchased, and simplify mix adjustment to one reg instead of two. It would be nice to make the piston 1:1 for simplicity, but that will put a cap on mix # due to vapour pressure, so I may go 2:1 with double the fuel meter volume.

Also hope OP doesn't mind continued discussion slightly ot here :)

Posted: Tue Jun 23, 2009 10:49 am
by MRR
@sniper hero
This hammer or push valve is not like yours. It consist of two equal or nearly equal surfaces and cancel each other out. The only force that keep the valve closed is the spring, even at high pressure.

There is a link to the topic of BtB in the description.