Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 81 users online :: 3 registered, 0 hidden and 78 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

new valve design?

A place to ask general spud cannon related questions.
Sponsored 
  • Author
    Message

new valve design?

Unread postAuthor: spikerbond » Thu Jun 03, 2010 5:43 pm

i have been thinking about this for awhile but just had some free time to make it in flash. do you think this will work? any comments/suggestions?

Image
  • 0


spikerbond
Private First Class
Private First Class
 
Posts: 28
Joined: Thu Apr 16, 2009 9:11 pm
Reputation: 0

Unread postAuthor: theBOOM » Thu Jun 03, 2010 5:49 pm

Not sure but I believe that's how Techs qdv sort of works?
  • 0

User avatar
theBOOM
Major
Major
 
Posts: 374
Joined: Wed Jun 03, 2009 10:49 pm
Location: San Antonio, TX
Reputation: 0

Unread postAuthor: saefroch » Thu Jun 03, 2010 5:50 pm

Looks to me like a very interesting take on a coaxial piston valve. I see no real reason it wouldn't work, but I've little experience with coaxial designs. It seems like this design may afford better valve opening speed, with a slight delay after piloting. Debatable whether or not you'll notice the efficiency increase, but based on personal experience, I'd say you would. Pretty much what it looks like you're trying to do here is use a larger pilot volume to actually increase efficiency.

EDIT:It looks like Tech's QDV but works nothing like one. It does however employ the same body design. Tech's QDV has no pilot volume or pressure, and the piston sits with the two chamber connection holes between its o-rings.
  • 0

User avatar
saefroch
Major General
Major General
 
Posts: 1679
Joined: Mon Jun 08, 2009 8:47 am
Location: U.S.A.- See Map
Country: United States (us)
Reputation: 0

Unread postAuthor: theBOOM » Thu Jun 03, 2010 5:56 pm

Yes it has the ports, and this sytem would need orings to work. I think this would work because air pressure acts in all different surfaces, I think its the same principle but tech's qdv actually manually moves the piston back to allow air through the barrel.
  • 0

User avatar
theBOOM
Major
Major
 
Posts: 374
Joined: Wed Jun 03, 2009 10:49 pm
Location: San Antonio, TX
Reputation: 0

Unread postAuthor: frocksie » Thu Jun 03, 2010 6:08 pm

This valve wouldn't fire, because the chamber would vent through the pilot. Also, there is no pressure acting on the barrel face of the piston, so even if you could vent the pilot without depressurizing the chamber, the piston would remain up against the pin/stopper.

However, its always good to be thinking of new ideas and trying to innovate. Keep it up.
  • 0

“He who controls the present, controls the past. He who controls the past, controls the future.”
-George Orwell
User avatar
frocksie
Sergeant
Sergeant
 
Posts: 91
Joined: Fri Mar 23, 2007 2:05 pm
Location: Maine
Reputation: 0

Unread postAuthor: Hotwired » Thu Jun 03, 2010 6:14 pm

What would stop the entire chamber exhausting out of the schrader valve when you opened it?

When you try to pilot the valve it won't just let out the volume in the pilot area, the chamber will keep trying to refill that.
  • 0

User avatar
Hotwired
Lieutenant General
Lieutenant General
 
Posts: 2599
Joined: Fri Oct 13, 2006 5:51 am
Location: UK
Reputation: 0

Unread postAuthor: potatoflinger » Thu Jun 03, 2010 6:29 pm

This design will work, however you will need to make at least one change. The piston will have to be lengthened (or the red hole drilled closer to the back of the piston) so that the piston almost completely covers up the hole when the valve is closed. The opening of the hole when it is blocked by the piston has to have less flow than the schrader valve (or any other valve that you decide to pilot it with) so that the pressure on the pilot side of the piston will decrease.

Another option you have is to drill the hole so that it is completely covered by the piston when the valve is closed, but then only have an o-ring on the front portion of the piston in front of the hole. That way the only opening that the air will have to travel from the chamber to the pilot will be the difference between the diameter of the tube that the piston slides in and the diameter of the piston.
  • 0

It's hard to soar with eagles when you're working with turkeys.
User avatar
potatoflinger
Brigadier General
Brigadier General
 
Posts: 1136
Joined: Thu Nov 02, 2006 3:26 pm
Location: Maryland
Reputation: 1

Sponsored

Sponsor
 


Unread postAuthor: spikerbond » Thu Jun 03, 2010 6:57 pm

Hotwired wrote:What would stop the entire chamber exhausting out of the schrader valve when you opened it?


i forgot to put the spring in between the piston and that small green stopper pin. that would push the piston back.
  • 0


spikerbond
Private First Class
Private First Class
 
Posts: 28
Joined: Thu Apr 16, 2009 9:11 pm
Reputation: 0

Unread postAuthor: Technician1002 » Thu Jun 03, 2010 7:02 pm

Watch the forces on the piston. When filling the piston is pressed forward. When done filling, the pressure remains pushing the piston forward. When firing, the air vents out the pilot. The pressure remains on the piston pressing it forward. The only thing missing is a way to push the piston back against the pilot pressure. A slight mod to prevent the air from pushing the piston forward would make it a QDV. Another slight mod to add an air cylinder with a spring to close the valve and air to yank it open and you have one of my future designs for a semi auto.
  • 0

User avatar
Technician1002
Chief of Staff
Chief of Staff
 
Posts: 5190
Joined: Sat Apr 04, 2009 11:10 am
Reputation: 14

Unread postAuthor: jor2daje » Thu Jun 03, 2010 7:44 pm

As has already been said there is no force acting on the piston to open in when the pilot is vented.
  • 0

Patience is a virtue, get it if you can, seldom in a women, never in a man.
User avatar
jor2daje
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 418
Joined: Sun Oct 05, 2008 9:41 pm
Location: Southern California
Reputation: 0

Unread postAuthor: spikerbond » Thu Jun 03, 2010 7:49 pm

jor2daje wrote:As has already been said there is no force acting on the piston to open in when the pilot is vented.


and as i said, two replys above, there will be a spring between that small green stopper pin and the piston
  • 0


spikerbond
Private First Class
Private First Class
 
Posts: 28
Joined: Thu Apr 16, 2009 9:11 pm
Reputation: 0

Unread postAuthor: Technician1002 » Thu Jun 03, 2010 7:50 pm

jor2daje wrote:As has already been said there is no force acting on the piston to open in when the pilot is vented.


There is a force.. from the chamber.. until the entire chamber is vented out the pilot. I guess you are right.. To open.. There is force holding it closed.
  • 0

User avatar
Technician1002
Chief of Staff
Chief of Staff
 
Posts: 5190
Joined: Sat Apr 04, 2009 11:10 am
Reputation: 14

Unread postAuthor: spikerbond » Thu Jun 03, 2010 7:53 pm

IS NO ONE READING MY POSTS ABOUT THE SPRING THAT WILL PUSH THE PISTON BACK?!?!
  • 0


spikerbond
Private First Class
Private First Class
 
Posts: 28
Joined: Thu Apr 16, 2009 9:11 pm
Reputation: 0

Unread postAuthor: potatoflinger » Thu Jun 03, 2010 7:56 pm

I read and understood the post about the spring in front of the piston. This design will work, you just have to read the post I made earlier and make a few changes.
  • 0

It's hard to soar with eagles when you're working with turkeys.
User avatar
potatoflinger
Brigadier General
Brigadier General
 
Posts: 1136
Joined: Thu Nov 02, 2006 3:26 pm
Location: Maryland
Reputation: 1

Unread postAuthor: Lockednloaded » Thu Jun 03, 2010 8:12 pm

It may work if you can put it all together precisely and with out leaks, but why would you want this valve? It seems less efficient than a piston in the same configuration, but kudos on the animation and the concept
  • 0

I love lamp
User avatar
Lockednloaded
Major General
Major General
 
Posts: 1558
Joined: Thu Sep 03, 2009 9:38 pm
Location: Texas, USA
Reputation: 0

Next

Return to General Spud Cannon Related

Who is online

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot]

Reputation System ©'