prototype valve

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spud yeti
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Thu Jun 28, 2007 7:34 am

I was looking how a sprinkler valve works, and decided to do a bit of designing.
I have used the concept partially, but a lot of this valve is new and pretty much prototype.

It works that the air in the top piece plus the spring holds the neoprene disk down and stops air from escaping. When the blow-off valve is pulled the air from the bottom can push the disk up and allow air to escape.

Theoretically it should work, but I havent had the time, or effort, to make it yet. I only have one problem. That is that when you pull the blow-off valve air is still going to be rushing in, and this could waste air!
Please give your suggestions!
(click on the pictures to see them clearly)
Attachments
open
open
sprinkler open.GIF (8.92 KiB) Viewed 1908 times
closed
closed
sprinler closed.GIF (7.58 KiB) Viewed 1908 times
really good quote/phrase here
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lukemc
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Thu Jun 28, 2007 7:47 am

so it is entirely a home made sprinkler?
it wouldnt work the way you have it your "eqilization hole" must be smaller than your piolit
"Those who are different change the world. Those who are the same keep it that way"
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spud yeti
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Thu Jun 28, 2007 7:57 am

Yeah, its entirely home made. I guess I didnt make the pvc etc, but to an extent it is.
btw, the pictures not to scale or anything, and the pipe is smaller, but its a bad drawing that was just made to show the concept.
really good quote/phrase here
Gepard
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Thu Jun 28, 2007 8:35 am

You shouldn't need the spring and guide. ...

Any thoughts on a suitable diaphragm?

Michael
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praetorian91
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Thu Jun 28, 2007 10:06 am

Heres the solution to your problem:

Most sprinkler valves use only a tiny equalizer hole to release air into the top part of the valve to close the diaphragm. When the valve opens, only a tiny bit of air can be wasted because of the minute size of the hole. You plan on using copper pipe to equalize your valve, and because the copper pipe has a gigantic diameter compared to the traditional equalizer "hole", you will waste a ridiculous amount of air, if the valve even opens at all.

How do you fix this? Easy. Eliminate the copper pipe and instead poke a tiny hole from your chamber to the upper part of the valve.
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spud yeti
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Thu Jun 28, 2007 12:04 pm

Yeah, i thought of that, but then at first whats stopping the valve from blowing open before air has leaked into pilot?? Oh yeah, and i dont think I would have used copper pipe, it would have been thin plastic tube (dont know what I was thinking when i wrote the diagram :oops: )
gepard - I was thinking of neoprene disk.
really good quote/phrase here
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praetorian91
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Thu Jun 28, 2007 12:48 pm

Remarkably, the air leaks fast enough to seal the valve. Any sprinkler valve is proof of this.

I think very small diameter plastic tubing might work, although it may still be too much. Try it and see, as the rest of your plan looks solid.

A neoprene disk will work perfect as the diaphragm.

Looking forward to seeing this one finished! Give me a heads up when its done.
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dongfang
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Thu Jun 28, 2007 2:46 pm

Hi,

Just a silly remark - you can also place the inflator valve for the chamber in the lid of your design. Air will rush backward through the eq hole, but the ´phragm will be pushed down nice and firm all the time.

I (and probably many others) do that with Rain Bird sprinkler valve - I do it because I cannot make a port in my chamber, it is too weak. I can remove the spring in the valve without problems this way.

What distinguishes your design from a sprinkler, except that it is home made?

Regards
Soren
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spud yeti
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Fri Jun 29, 2007 3:54 am

Nothing! LOl, I was just seeing if it could be done. I guess the price is the difference! :D
No, at first I had some different designs that were different and I forgot to take out the piece that says its all different, sorry!
Thanks a lot for all the input though!

I will continue on my quest to create thine sprinkler valve...
But I thought of a totally new concept last night and Im getting right to it now! :D
I'll post it on once Ive built it this time!
BTW, dogfang, I think I'll try out your method, youre a genius!
really good quote/phrase here
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