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["steve jones" <stevendella AT finnsheep.com>]

Hi Bill,

I can hook all the bores together with a suction pump but can only draw  
down a few metres so the water flow is quite poor. Something pumping from  
the bottom with access to the whole 80 feet of the bore should pump more  
water.

A guy called Feri Pumps sells something like this air lift pump here but  
he wants A$1000 each for them. I wonder whether I would be better to bring  
electricity to each 4 inch bore and place submersibles down them. (There  
are going to be twenty at least though - very hard work drilling them all  
by hand you can believe me - but it's what we can afford. Very bad drought  
here still and not much money in sheep farming alas.)  Either of these two  
options is getting to be seriously big money though.

Just Posted your previous posts on this topic below to make sure we are  
talking about the same thing. Earlier your model comprised two floating  
balls presumably to act as the check valves (= one-way or non-return  
valves? Yes?)Previously you said you had a simple mechanical means of  
cycling the pump. Now I take it you are using a 555 timer and a 3-way  
solenoid valve plus some circuitry, power cable, power supply etc. If I  
have to bring power to each bore it might be more efficient in the  
long-term to have submersible pumps? Or can the circuit operate off cheap  
rechargeable batteries or something? I can probably make up your system if  
I have a little more detail though maybe I would favour a simple  
mechanical system. I don't quite understand the explanation in your  
posting below (or in your reply). Some diagrams would help if you have any  
- or pictures?

The whole thing has to fit down a 4 inch hole. Mr Feri's does. Can yours?

Thanks in anticipation,

Steve Jones,
Morwell Victoria Australia.

PREVIOUS POST:

Here's a picture of a Stauffer pump.  It costs $500 if you buy one of
their windmills, $800 otherwise.  About 10 years ago I conceived of a
way to lift water just by injecting pressurized air into a water-filled
chamber, to drive it upward through a one-way check valve.  I knew what
it had to do, but I didn't know how to make or acquire the necessary
valves.  Later when I first went online, I learned that someone already
made one:

http://www.airliftech.com/Windmill%20water%20pump.jpg

As of about 3 years ago, I found an easy to make the tube seal and
refill with water, using a floating ball that presses against a hole in
the top of the chamber when the chamber is filled with water, and stays
there during pressurization.  Upon releasing the air pressure, the ball
falls to the bottom and the chamber refills with water.  But I still
couldn't figure out how to sense when the chamber is ready to refill
again.  It's easy to make it cycle at a constant rate, but the rate
needs to increase when the wind blows harder, producing more air from
the compressor.

So yesterday I had an idea to put a second identical floating ball in
the tube, with both balls large enough that they can't slide past each
other.  Now as the water is forced out of the bottom of the chamber, the
lower ball will ride downward along with the meniscus of the water, and
when the chamber empties it will be forced against the bottom hole.
This will cause the pressure in the air supply tube to increase, since
the trapped air has nowhere to go, which can easily be sensed with a
pressure switch!

The only remaining (easy) task is to come up with a circuit that will
turn on a 3-way solenoid valve (or off, depending on which type of valve
it is), to turn off the air pressure when the pressure switch cuts out,
and then delay for a fixed length of time before resetting, to allow the
top ball to fall and the chamber to refill.

The whole thing is less than $100 and you can make a compressor to run
it from an old engine.  Our wind nearly always blows from the north in
summer, clockwise around that offshore high pressure cell I talked
about, so even a simple windmill that always points north would work
fine, and it can have a simple belt drive connection.

> The only remaining (easy) task is to come up with a circuit that will 
> turn on a 3-way solenoid valve (or off, depending on which type of valve 
> it is), to turn off the air pressure when the pressure switch cuts out, 
> and then delay for a fixed length of time before resetting, to allow the 
> top ball to fall and the chamber to refill.
That will definitely work, but today I mastered the secret of pure
mechanical control.  When the pressure rises, indicating that the
chamber is full of air and ready to reset, a pressure-relief valve
releases the air from the line.  This would work by itself, but poorly.
My buddy Orlando was happy with this arrangement, but I see only
inefficiency as the air blows uncontrollably, first out the valve, and
then out the top of the chamber, whose top ball will have now fallen,
perhaps even interfering with the top ball as it tries to seat itself.

So I had an idea to use a valve that would shut when the air flow goes
above a certain rate.  It would be like the pneumatic equivalent of a
circuit breaker, one that resets itself.  It turns out that the valve I
need is precisely the one that James was talking about for the hydraulic
ram pump a few months back.  It's actually a one-way valve, the
pneumatic equivalent of a diode, placed backwards in the line, which
allows only a low rate of flow in the "wrong" direction.  This one has
to work for air, but it's the same principle.

The one tiny problem remaining is how to make this valve reset.  It
stays shut until the pressure on both sides nearly equalizes, I would
think.  Well, here's how to solve that problem.  A second air tube is
connected directly from the pressure supply to the chamber, bypassing
the "circuit breaker" valve, but through a valve that barely leaks air
in at all (the pneumatic equivalent of a large electrical resistance).
This way, very little air is wasted during the reset of the system, but
when the top ball plugs the hole, only a little air needs to seep in
through the second tube to repressurize the chamber, and that allows the
built-in spring to reset the fancy valve, allowing air to flow freely
into the now sealed chamber.

Mr. Stauffer deserves a patent for this device, unlike so many other
patents I've been embarrassed to learn of.  After all, it took me ten
years of off-and-on cogitating to figure it all out.  But the hour is
late, and the ecovillagers don't deserve to starve to death because they
can't afford $800 for a water pump.  Wasn't all that *simplicity*
supposed to help lower the price?  So now I'm happy to announce that
anyone can build one for under $100.

Bill
S. Oregon coastOn Fri, 22 Feb 2008 09:30:10 +1100, Bill Jones  
<billj AT harborside.com> wrote:

> steve jones wrote:
>
> > Hi Bill,
> >
> > I have been trying to contact you re details about your 'well pump
> > breakthrough'. I've tried several times to send you an email without
> > success. I have now joined this homestead thing to see if I have better
> > success. The info you posted on the net is not quite detailed enough for
> > me to build one. I am trying to install a small irrigation system here  
> > in
> > Morwell Victoria Australia. I am hand drilling a number of 25 metre  x  
> > 100
> > mm (80 ft x 4 in) wells in a fine sandy aquifer. There is plenty of  
> > water
> > but it doesn't flow very quickly so linking several with compresed air
> > pumps to produce a reasonable flow of water would be a good idea.
> > Unfortunately the commercially available pumps are at least $1000 each  
> > and
> > this makes for financial problems. If I could build them for $100 each  
> > as
> > you suggest I would be very grateful. My email address is
> > stevendella AT finnsheep.com I hope you are able to help.
> >
> > Cheers,
> >
> > Steve & Della Jones.
> Hi Steve.  Your email is probably buried on my hard drive, but I've had
> several system crashes, so who knows?
>
> Indeed, an air-displacement pump can just wait as long as necessary for
> the well to refill, so low flow rate is no problem.
>
> Well, it's just a vertical tube submerged in the water.  At the bottom,
> an inlet port lets water in through a check valve.  A second check
> valve, also at the bottom, serves as the water outlet, and connects to
> the return tube.  These two check valves face in opposite directions.
> Now, if there were a piston at the other end of the tube, water would be
> forced upward through the return tube when the piston compresses, and
> new water would be pulled in when the piston draws back.
>
> In these respects it's just like any other piston pump.  But instead of
> a piston, air is injected into the top through a long tube.  The bubble
> of air acts exactly like a piston.  It forces the water out the outlet
> valve.  Gravity is the only thing keeping the air in the top of the
> tube, and the water in the bottom, so that's why the tube must be held
> vertical.  No need to have a piston pull back to draw in the water,
> since it will just flow in by itself through the inlet valve once the
> pressure's off.
>
> Now you only have to find a way to make the air turn on, and disconnect,
> every few seconds.  We're using a simple 3-way solenoid valve, and a 555
> timer circuit.  We have no particular skills in electronics, but we were
> still able to hook up a 555 chip with no problem.  The system will be
> somewhat less efficient to operate if the solenoid valve is placed above
> ground, because of the long tube of air that's lost during each cycle,
> but we like the idea of not having electricity and solenoids down in the
> humid well shaft.
>
> This is as simple as it gets.  There are commercial models that have a
> pair of water-level detectors inside, so they "know" when it's time to
> change to the other state.  This seems like overkill to me.  Since it
> always takes the same amount of time to refill, and a different (but
> always the same) amount of time to empty out, this feedback isn't really
> necessary.  There are models that pulse the air flow on and off using
> purely mechanical means, but they're much more expensive, and I've heard
> they have troubles with stalling out.  Either way I'm always amazed at
> the huge prices and sophisticated stuff, when it's really just a giant
> keg tapper.
>
> Bill
> S. Oregon coast
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