Go to Post My students like to win, so I'll stick to enabling that. - sdcantrell56 [more]
Home
Go Back   Chief Delphi > Technical > Pneumatics
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Reply
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 03-01-2017, 23:15
daniellieb01 daniellieb01 is offline
Registered User
FRC #5190
Team Role: CAD
 
Join Date: Jan 2017
Rookie Year: 2012
Location: North Carolina
Posts: 2
daniellieb01 is an unknown quantity at this point
Question Check valves that trigger at a certain pressure?

I'm looking for a valve similar to a check valve but will allow air to flow through once the system reaches a certain air pressure. Is there such a valve that egisists? If so are the FRC legal?
Reply With Quote
  #2   Spotlight this post!  
Unread 03-01-2017, 23:37
headlight headlight is offline
Registered User
no team
 
Join Date: May 2013
Rookie Year: 2012
Location: Rochester Hills, MI
Posts: 69
headlight is an unknown quantity at this point
Re: Check valves that trigger at a certain pressure?

I think what you're looking for is called an adjustable check valve. Here or here


As for their FRC legality, standard "rules aren't out yet" disclaimer. Under the previous rules you may have been able to consider them a check valve (R77 G), or perhaps a "passive flow control valve" (R77 F).
Reply With Quote
  #3   Spotlight this post!  
Unread 04-01-2017, 07:25
GeeTwo's Avatar
GeeTwo GeeTwo is offline
Technical Director
AKA: Gus Michel II
FRC #3946 (Tiger Robotics)
Team Role: Mentor
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Slidell, LA
Posts: 3,564
GeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond repute
Re: Check valves that trigger at a certain pressure?

Quote:
Originally Posted by headlight View Post
I think what you're looking for is called an adjustable check valve. ...


As for their FRC legality, standard "rules aren't out yet" disclaimer. Under the previous rules you may have been able to consider them a check valve (R77 G), or perhaps a "passive flow control valve" (R77 F).
That would be a considerable stretch of the rules. If the rules this year read like last year's that would definitely be a Q&A item. If the Q&A ruling is (for example) "yes, an adjustable check valve is a check valve", then you would have strong documentation to support your claim at inspection, and you could expect uniform application at different events. LIkewise, if you get a "no" ruling, you should be able to expect other teams not to be able to use them either (though of course, things get missed).

The pneumatics rules in recent years have been such that nothing is allowed unless is specifically listed as allowed in a pneumatics rule. (In contrast to most mechanical items such as arms or gearboxes, which are allowed unless there is a rule which excludes them.)
__________________

If you can't find time to do it right, how are you going to find time to do it over?
If you don't pass it on, it never happened.
Robots are great, but inspiration is the reason we're here.
Friends don't let friends use master links.
Reply With Quote
  #4   Spotlight this post!  
Unread 04-01-2017, 08:36
Unsung FIRST Hero
Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1996
Location: Wheeling, IL
Posts: 10,766
Al Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond repute
Re: Check valves that trigger at a certain pressure?

There is actually a check valve in the output of many of the legal compressors. It is required for operation. However, in all cases, COTS pneumatic parts must allow all stored pressure to be released when the Pressure Vent Plug Valve is operated.
__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
________________________
Storming the Tower since 1996.
Reply With Quote
  #5   Spotlight this post!  
Unread 04-01-2017, 09:26
FrankJ's Avatar
FrankJ FrankJ is offline
Robot Mentor
FRC #2974 (WALT)
Team Role: Mentor
 
Join Date: Feb 2011
Rookie Year: 2009
Location: Marietta GA
Posts: 1,899
FrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond reputeFrankJ has a reputation beyond repute
Re: Check valves that trigger at a certain pressure?

What you are looking for is called a back pressure valve. The simpler ones are essentially a check valve with either an adjustable spring tension or preset to open at the desired pressure. "back pressure valves" were not a listed legal component under 2016 rules. "Check valves" were listed components and legal under 2016 rules. A definition thing. In any case it would have to be plumbed to meet the other rules, as Al said. The relief valve required on the robot is actually a check valve with adjustable opening pressure.
__________________
If you don't know what you should hook up then you should read a data sheet
Reply With Quote
Reply


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 05:22.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi