Sequencing / Indexing Valve

Sequencing / Indexing Valve

Hello Everyone, A couple of years ago, I had designed a sequencing
valve to fill 6 different grow beds in my aquaponic system. It has been running continuously
for 2 years without clogging with solids or needing maintenance. The micro-switch used
for the indexing positions has finally worn out. I was going to patent the design, but it’s
too expensive with too little return so I’m now sharing the design. Also, a good commercial
sequencing valve that has a completely different style of indexing is available which works
well. While I have it dismantled, I will replace the latex tubing since it is starting to rot. The indexing mechanism uses a windshield wiper
motor running on 5 volts and has a 6 sided cam that a micro-switch travels around. Power
is applied to the normally closed pole which will turn on the motor through the common
pole. When the cam moves to a high position the switch opens and turns off the motor.
When it’s time to move to the next position, power is applied to the normally open pole,
turning on the motor again until the switch travels to the next area of the cam. There is also a secondary cam that has one
indent at the first position. This is to allow the controller to reset the valve to position
one in the event of a power failure. Removing the cover exposes the internal workings.
There are 6 latex tubes that are located around a cam with a small ramp cut into it. As the
cam rotates, the ramp area will push against the slider which will pinch and hold the tubing
closed. As the cam continues, the next positions slider will spring open. One nice feature
about using a pinch valve is that there are no seals needed. The mechanics never touch
the water! The water is fed into the valves through a
ring with 6 tee connectors. The latex tubing is attached to each of the tee’s and a zip
tie is attached to insure it won’t slide off the barbed fitting. The 6 latex tubes are inserted through the base
cover. They are then inserted through the center ring section. The master cam is placed onto the rotating
shaft. There is a wing-nut connected to the shaft and the wings are used to anchor the
cam to the shaft. Latex tubing is very flexible and pinches
closed easily. The sliders that pinch the tubing closed have a peak on it. The anvil
on the other side has a valley cut into it. When this area pinches the tubing, it also
folds it a bit which creates a tighter seal. The anvil rests on a screw so it can move
around a bit so the slider and anvil will always align while it is being pinched. The final cover is placed over the mechanism
and the tubing pulled through. There are 6 bolts that pass through the entire assembly
which hold it together. Here is the entire sequencing valve installed
in the greenhouse. I hope you enjoyed this video and we would appreciate it if you visited
our web site at for more details about our products. Thanks for watching!

Daniel Ostrander

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23 thoughts on “Sequencing / Indexing Valve

  1. tobirod7 says:

    Don't know what u use it for. A beautiful design though!
    Great job!

  2. Bigelow Brook Farm (Web4Deb) says:

    @tobirod7 LOL. very niche market! It's so I can have one fish tank with one pump, and then pump the water into the grow beds one at a time so I don't consume all the water at once. Check some of my other greenhouse videos so you can see the entire setup. Thanks!

  3. RastaBot says:

    That is awesome….thanks for sharing.

  4. WorldStove says:

    elegant brilliance!

  5. Bigelow Brook Farm (Web4Deb) says:

    @uteplats Printing it would be cool….probably expensive. These are just chucks of scrap poly I got from a tank manufacturer and cut the pieces with a hole saw or by hand.

  6. Big Game James says:

    great work thanks for sharing, shame about the patent. Looking forward to seeing more vids on your geodesic greenhouse. Taz from BYAP.

  7. Bigelow Brook Farm (Web4Deb) says:

    @bigamejames1 Over 10 grand these days to cover a US patent…you have to sell a boatload to cover the costs. The next video is in the works….got a lot of mud in the area I'm wading through….

  8. dave spencer says:

    well done, very simplistic mechanical solution. I love it, thanks so much for sharing

  9. Kirk Crawford says:

    I suggest when you upgrade your selector next time, replace the wheeled micro switches with optical slot detectors. That eliminates moving parts and they will never wear out. You may need to modify your rotating disks to have a slot in them in addition to the the ramp. Something like DigiKey part OR529-ND.

  10. Bigelow Brook Farm (Web4Deb) says:

    @mozul Good idea. But for $25 vs. a 2 dollar switch, I'll just replace the switch every 2 years. 😉

  11. timmit59 says:

    Fantastic! Good on you for sharing your designs. Patents just block other people from innovating anyway, and given the current global economic situation aquaponics is a technology that needs promoting not blocking. I don't know US IP laws, but would it be cheaper to get a 'creative commons' on the design? This would at least stop somebody else patenting it and ensure the design remains free to use.

  12. Bigelow Brook Farm (Web4Deb) says:

    @timmit59 Once a design is put into the public domain it cannot be patented. However if someone is stupid enough to go through the expense of doing it, it can be easily challenged (and voided).

  13. Don Mallicoat says:

    would you mind posting the part #'s that you used for the relay and switch as well as the voltage/amps for the motor and from the timer… I'd really appreciate it.
    Also, how did you come upon the poly?

  14. Bigelow Brook Farm (Web4Deb) says:

    The motor is just a windshield wiper motor that runs at 12VDC. I don't have any part numbers for anything since I just made it from junk I had laying around. I'm fairly sure you can get the poly from McMaster-Carr.

  15. Don Mallicoat says:

    Thanks for the quick reply. I went to Home Depot, Lowes and standard plumbing and none of them had the latex tubing. Where did you source that ?
    Thanks for the help and info.

  16. Bigelow Brook Farm (Web4Deb) says:

    go to mcmaster . c o m and search for item # 5234K262

  17. k_froggy says:

    Whats the total cost of a vale like this vs. the commercial one? Im thinking next year i will put in a fairly good size aquaponic system in my backyard for lettuce and whatnot.

  18. Bigelow Brook Farm (Web4Deb) says:

    buy the commercial one,

  19. Don Mallicoat says:

    I had to put my system on hold for a bit and am getting back to it.
    I'm trying to find an appropriate (DPST?) rocker switch similar to what you used. The switch seemed like it might be k on this page. mcmaster dot com/#catalog/119/886/=m5655y
    They're not terribly pricey, but time wise I'd like to avoid a problem if possible. I appreciate your help and feedback as always. If I can ever do anything to say thanks, let me know.

  20. Bigelow Brook Farm (Web4Deb) says:

    that looks like it will work fine….any of those micro switches with the rollers built into them work fairly well. I got mine at radio shack. I think it was around 4-5 bucks.

  21. Don Mallicoat says:

    After working for several days to make this, I think I'm giving up. When it turns, the pieces don't slide in as they should, instead they just seem to bind.

    I looked at the sequencing valve you show in the video as well and I don't get how that one could be used as it has to have 0 pressure at sequencing, which means I'd have to turn the pump off when sequencing.

  22. Eruman Bredberry says:

    Hi! How to design a durable?

  23. R Johnson says:

    Thank you for sharing this!

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