A Soda Bottle SIP With An On-Off Switch

This is an original working prototype of a sub-irrigated planter (SIP) device I invented about thirty years ago. With little belief in the receptivity of the marketplace at the time, I chose not to patent and market it. Had I gotten a patent it would now be expired. Eventually someone did discover the same idea and I believe there is a patent.

The objective was to design a more cost effective and universal vacuum-sensor system that would work in any watertight container. The system works. I used if for a wide array of plants in my home, including specimen Ficus benjamina trees.

With advances in plastic molding technology, perhaps it is worth producing these things today. Anyone interested?

The system is modeled on the one used by the Planter Technology Natural Spring planter and Controlled Watering Insert (CWI). Incidentally, it is not well known that the patent held by the original owners (there is now a new owner) of Planter Technology at the time was really a copy of a patent held by William Crane, Jr. He died before he could do anything with it. It still puzzles me how PT was able to get away with all this. I suppose Crane’s widow could have sued but she did not. That’s easy to understand.

Anyway, here is how it works. The plastic tube coming out the neck of the bottle has a porous plastic tip. The bottom of the bottle has a porous plastic water vent.

When the soil is dry, air can flow through the sensor tip. That allows water to flow from the bottom water vent. The water then rises by capillary action until the soil around the sensor tip becomes moist.

When the sensor tip becomes moist (from the surrounding soil), air is prevented from flowing; a vacuum is created inside the bottle and the water stops flowing from the bottom.

In everyday life, it's the same as holding your finger on the top end of a straw in your drink. If you lift the straw, holding your finger on top, your drink liquid stays in the straw. That’s' because there is now a vacuum above the liquid in the straw.

When you remove your finger the vacuum is broken and the drink liquid flows out of the straw. Simple, eh?

Using two simple principles of physics (vacuum and capillary action) the system works automatically and in effect has an on-off switch. I still wouldn't call it "self-watering" though. Controlled watering is okay but not self-watering which implies plant intelligence that does not exist.

Comments

[Kevin]

Great info. I'm looking into making a 2 liter bottle garden or using them in such way as you explained here.

Kevin Florida (USA)

[Max Buster]

Brilliant!

We want to re-create what you've described. Two questions:
1) What materials would you recommend for the "porous plastic tip"?
2) Is porous material really required for the bottom hole? If so, what would you recommend.

Finally, please visit the URL we entered to see if we have presented your other brillant ideas to your satisfaction.

Thank You,

Max Buster

PS - Would it be possible for you to send us your email address?

[Greenscaper]

Well done. One typo here:
"Some are some other pictures from Mr. Hyland using the same concept:"

I used a sensor tube assembly from a Planter Technology planter that I had. http://www.plantertechnology.com/products/parts_sensors.html

It looks like you need to call Planter Technology to buy the sensors. Just tell them you bought or were given some used Natural Spring or CWI planters.

You could make them yourself but it will take some effort to source the components. I don't think any of them are proprietary parts.

I believe there are other variants of the "vacuum/sensor" system. You will probably find them by doing some patent searching. There are now a number of websites that make that much easier to do than previously using the USPTO website. Who knows what new approach you guys might create.

You're doing good work of value to society! I checked out your 2010 summer project. We should discuss this further. What you are doing is compatible with the goals of the U.N. Food And Agriculture Organization (FAO). I believe they are based in Milan, Italy. http://www.fao.org/ Media cost and availability is a key issue and we are not doing enough research on the subject here in the U.S.

Is your dad an architect that you know Mies?

You can reach me at urbangreenscaper [at} gmail [dot] com. Feel free to contact me with any questions. I'll be going into the hospital for knees(s) replacment surgrery in the next month or so. I'll blog about it when I do.

[Brittan]

Hello,
I'm not sure i understand all, because English is not my first language. Would it be possible to have more pictures or a video that shows the principle?
That would be nice! Thank you