small pump?

[windyknight]

I need a small (but not micro) solar or other dc pump for a model i've built. It must have min. 3 ft lift but only with very small flow (say 1 gall/hr), be continuous rated and preferably in uk.

Any ideas?

Thanks

[crashk6]

Jump onto eBay click buy and type in the search term "solar pond".

Solar fountain and pond pumps are on eBay all the time, in fact I just checked and saw quite a few.

--

crashK6

[Clifford]

I've seen lots of solar pond pumps.

Also look at:

sump pumps

bilge pumps (boating)

ordinary pond pumps

fishtank pumps (maybe these are just air pumps, but perhaps there is some kind of a fishtank pump, or the aerators could be modified.

Electric (or mechanical) Auto fuel pumps (yep, those would be 12V DC).

You might find something under lab equipment, although most lab pumps isolate the substance from the pump, and thus might waste power.

We use diaphragm pumps at work.  The concept is extraordinarily simple, and could easily be miniaturized.

[ghurd]

How about few bad ideas?

"Metering Pumps" are often DC and low volume.

Surplus medical style pumps are far less expensive than new lab styles,

But none seem very efficient to say the least.

Maybe they could run less volume with less watts for more efficiency? Not sure.

A boat bildge pump and automatic live well timer switch?

Attwood V625? Under 1A at 12v, 425GPH or 7.1GPM with 3.3' of head.

Brushes and motor are 'done' around 80 days 24/7 with a 4' head.

That, with a timer switch at 50/50%, only running when solar is good, should last 2 years?

A fish tank air pump?

There are a few that are just a simple sloppy AC coil, and the diaphram has a neo in the center.  The last one I examined would work with liquid, 1.2W at 110VAC 50/60Hz, and cheap at US$8.  Looked about like a 35mm film can.

Needs a DC to 110ACV inverter, but probably very easy to make with 2 transistors.

(if this is an open system, an air pump could be a much better choice... using 'lift' instead of 'drag')

G-

[windyknight]

Thanks G

Bilge pump sounds a good idea and mathches my requirement much better than solar fountains and such like. Been thinking about modified air pumps for a while. System is open but can't get how you mean with lift instead of drag -some sort of venturi effect?

k

[ghurd]

The bilge pump idea will work best with a properly sized pump.

I like the Attwood pumps because they are efficient, cheap and available in many versions designed for different flow and head.

ie: The V625 ($18?) kind of peters out around 5' head, but it only takes 1A and moves a lot of water at a 3' head.

Another pump may use 3A for the same flow at 3' head, but still move a lot of water at a 8' head.

Timer switches are made by a lot of brands, just have to find one that is setable to the on/off requirements. Not cheap at $35 to $60 ish.

Bubbles.

Pretty much, you blow small bubbles in a pipe of water.

Now that water weighs less than the other water, so it rises.

And the bubbles also push the water as they rise.

Many cheap fishtank filters work this way.

Coffee perkolaters (sp?) work about the same way with boiling bubbles.

Not sure how this explains it, but it has a drawing and math.

http://www.quantumlynx.com/water/back/vol2no2/v22_st5.html

G-

[windyknight]

very interesting -thanks

k