solenoid to pilot a hammer valve

[wyz2285]

no watt rating, continually for 30 sec. Anyone wants the video?

[dewey-1]

Most solenoids will get hot in a continuous mode of operation.
Either they must be designed for continuous mode or a method to reduce the holding voltage/current.

One example is if using a 24 VDC solenoid;
Apply 24V initially and then reduce to 12V for the holding voltage.

30+ years ago, I had to design a way to do this and it worked out rather well.

@wyz; you should not have this "30 second" heat problem once you use the circuit I gave you.

[wyz2285]

yeah I know, but solenoid too weak

[dewey-1]

yeah I know, but solenoid too weak

Is it "weak" with your NiCad batteries or another higher capacity power source?

Can you try using 24VDC on the 12VDC solenoid only for a short period of time to see if that makes it "stronger"?

[wyz2285]

I don't have a 24v source, and with the battery the solenoid already reaches the maxim power that says in the description

[al-xg]

Code: Select all

and with the battery the solenoid already reaches the maxim power 

That is the maximum power at 12V, will be stronger at higher voltages as long as the current isn't limited.

This is the one I'm using:
[youtube][/youtube]

It is powered by a 12V 3A supply.
It is rated to 25W at 12V so should only need ~2.1A, but if I connect it to a weaker 12V 1A supply it doesn't work anywhere near as well.

The point being you have to make sure you batteries can deliver enough power as Dewey-1 pointed out.

[POLAND_SPUD]

This is the one I'm using:

I see you put your arduino to good use

[wyz2285]

Did that system worked? My solenoid is strong enough to open the valve too, but the valve gets harder to open as the pressure raises, and probably your valve will have happen the same thing. That´s a 3-way right? Probably you will only use 10 bar max as most cheap 3-ways doesn´t holds more than that. My valve has better flow than a 1/4 3-way, as a 1/4 3-way normally has only 1.5 mm orifice, my has 6 mm, but my valve also will be harder to open.

[al-xg]

It should work past 70bar (it will hold the pressure and not leak, I'll be able to tell for sure sometime next week when I get home) but it is modified quite a bit, it is not the main valve it pilots a QEV.


Ooop I'm going to finish at home got to go

[wyz2285]

I know it pilots the QEV, where did you got the 3-way? how did you mod it to hold 70 bar?

[al-xg]

That is just a test setup, can't really get away with anything larger than a 1/8" QEV, it will quite easily pilot a 3/4" so flow isn't really an issue.

It's a 1/8" 5/2 valve solenoid valve, but used as a 3/2, just don't have a 3/2 handy. This one is just a cheap one from Hong Kong of Ebay, I have a couple of better quality ones at home though.

As far as the spool part holding the pressure, I'll be using epoxy to eliminate the need for seals, done that before works very well.
The tricky part is getting the solenoid to seal past 30bar. (they will hold 45bar for a few shots but then the spring yields slightly)
So I made a new piston that allows for any other solenoid+spring to be fitted.

So the valve is pneumatically assisted, all the solenoid has to do is to is break the seal on a seat less than 1mm in diameter.
I was going to go for direct acting (having tried this at 70bar with the spool part alone and moving it with my fingers) but the assisted version should be alot faster and in this case simpler to build.

I've only tried this particular setup to 10bar, but I'll be able to use it a full pressure when I get back.
I'll upload a video of it working at 10bar (short video though, I was at work, and it is way to noisy and suspicious sounding )
Edit:
[youtube][/youtube]

So can't say for sure that it will work at full pressure until I try it, but based on previous attempts this is looking pretty good so far.


But yeah anyway, all of this to show the MOSFET setup really, I reckon can bump a the pressure a bit more this way.

I see you put your arduino to good use

Every thing seems so easy with arduinos I'll should be able to use it more extensively when I get back.

[wyz2285]

This one is just a cheap one from Hong Kong of Ebay

Good for you for me ebay worth nothing
It would be a really nice semi/auto gun

[POLAND_SPUD]

for me ebay worth nothing

lol he posted tons of useful info like for example

shots but then the spring yields slightly

...but you mention ebay again

I'll be using epoxy to eliminate the need for seals, done that before works very well

Care to elaborate ?

The tricky part is getting the solenoid to seal past 30bar. (they will hold 45bar for a few shots but then the spring yields slightly)

you got some interesting results

solenoid valves are in many cases easier to get and cheaper than manual valves not to mention the fact that they are better than manual valves as they offer consistency... it would be cool to know how to mod them

please post more of it even if it isn't finished yet

One example is if using a 24 VDC solenoid;
Apply 24V initially and then reduce to 12V for the holding voltage

or get arduino and use PWM to do that

[wyz2285]

All the solenoid 3-way I can found only holds 10bar
So I was thinking of using a 1/8 12v 3-way to pilot a 1/4 QEV, at 10 bar it should be ok for airsoft.
And I found out what's wrong with my ebay account.

[dewey-1]

One example is if using a 24 VDC solenoid;
Apply 24V initially and then reduce to 12V for the holding voltage

or get arduino and use PWM to do that

Here is closest thing to Arduino when I did it 30+ years ago.
And I actually was using this D2 kit for the development of some future projects.

http://www.computermuseumgroningen.nl/m ... 800d2.html

Get Arduino and 3-way valve looks like a standardized answer/reply from POLAND_SPUD. Should be his signature.
He may rule the world when he finally interfaces the two together.