In 1975 Wally Minto donated a design to the world. His unpatented wheel worked on a change of temperature as low as 3.5 degrees.
Apparently if you handy with a welder you can build one too. You will need a selection of gasproof tanks of the same size and then weld them into a wheel shape.
Each tank opposing each other should have a hollow tube connecting them together.
Each tank should also have a low boiling point gas in them as well.
Arrange on a axle so that only one or two tanks will me immersed in heated water (solar Perhaps) Operation The bottom gas tank is immersed in a tough of water solar heated or otherwise.
The gas in the bottom is heated and the gas becomes lighter and flows to opposite tank where it cools down where it becomes heavier again.
The heavier gas tank is then drawn down by gravity and the process begins again.
The temp wheel rotates at slow speed but has high torque so step up gearing may give a higher speed output
For winter operation, a large heat collector buried under ground will supply the 3 and 1/2 degrees required to make it work during the winter.
In fact a bigger heat collector buried for winter use would be better along with a summer collector.
This Minto's motor will generate lots of power. If you need water or electricity this is the unit that could supply it.
Here,s an interesting email I recieved on this device
Hey I got a update for you on the Minto's wheel...you can add to your website...again make no reference to me, okay..Thanks Geoff....Okay instead of making it BIGGER to produce MORE POWER...
you just add on extra wheels on a common drive shaft...think of washers on a bolt, then hold it horzontial, side ways...then you have several
Minto's wheels producing MORE TORQUE and power on just one common drive shaft.
I got a few people to build a Minto's wheel..a video will come out next year sometime on it..cause its easy to build.
Also use 1 inch diameter tubing, it runs faster...not much tho...every little bit helps tho..ha ha...6 RPM is calculated...yeah right, lets see if it does it tho first..ha ha...its gonna take some tinkering and adjusting the valves to get it just right...slow it down so it has time to cool off will CONSTANTLY keep running..
well I think thats why Minto used small diameter brake line tubing...that took care of it for him ,limiting the speed that the liquid transfer from one container to another so it didnt spin too fast and would allow it to dump the heat so it could take on some more.
Alcohol can be used instead of propane, that's experimental still tho, okay, it just works in small table top models, that dont have to be under alot of pressure, you know, just a demo unit. Alchol is kind of expensive, Propane is not.
Alcohol wont explode tho, like alchol will if (when) someone tries to take your power supply away from you..NOT GOOD!!!
If you spin it too fast, then it will eventually stop...why? cause you didnt allow it enough time to cool off and dump the heat it took on when it was in the warm water tank.
..also cover it with a shade to protect it from the sun...other wise it takes on the sun's heat, warms up and then stops...ever stand in the sun, then the shade..ha ha.
..the shade is cooler and this thing needs the temperture difference to make it work...simple stuff for sure but nobody told me that.
..so you gotta learn by trial and error..ha ha...thinking about installing heat sink fins to take on heat and dump it faster, make them in-line so as to not slow a Minto's wheel down, not like a paddleboat wheel but positioned so like it would cut thru the water like a knife..not sure about this modification tho...cause it has to all balance out the entire wheel..(a pain to do,
oh yeah, another mod for you...if you cant put several Minto's wheels on a drive shaft, use a truck rear end, it can handle the weight and you got yourself a simple PTO, power take off, using the drive shaft
drive shaft Minto's ! Minto's 0================o===============0 wheel center of rear end wheel of truck
Think about, it will make sense...just so that you DO know...I didnt do this modification tho...thought about it alot, till the idea of putting several on a common drive shaft hit..cause then you got yourself some torque to spare and you can get sloppy in your power requirements math..ha ha...cause you got power to spare...yeah it always doesnt work like it does on paper, Geoff..ha ha
oh yeah, on the website, add the text that you need to install a set of valves to switch from the sun collector to the buried heat collector.
..some people will tell you to run it thru one first then the other....uh...it doesnt seem to work that great that way with both collectors turned on..
.why I dont know..I think one collector feeds the other collector and one acts as a heatsink for the other one...just my theory, what ever it is..
.something is going on...I could take some measurements but wont..it works or it doesnt...maybe different times of the year it might.
..I dont know...and use LARGE DIAMETER TUBING also for the heat collectors...without a pump it moves slow, maybe a pump could be added but then the heating water might move too fast...so a slow pump powered by the wheel might work.
..along with a solar cell running a switching circuit to control what valves are open to run the wheel at night from the heat in the earth, when the solar heat collector stops working..when the sun comes up it switches back to the solar heat collector.
.maybe a temp sensor would do better...well that then gets it all complex and I would rather people keep it simple and just build one and charge some batteries with it for night time use...the old keep it simple stupid principal..ha ha ------------------------------------------------------------------------------ -------------
On the minto's wheel...if you use one of the 5 gallon propane tanks...what most people dont know is you gotta take the valve off of the tank and un-screw the float mechanism inside of it, other wise when the tank turns up side down the float wont let it transfer all the propane liquid.
..it will transfer a little of it then shut it down... Uh...taking that float off...uh...kind of violates a safty device..if over pressure it will spray out only vapor.
..ALL the tanks have markings on them...use this side up only....some places fill your tank till it shuts off...others like TEXAS fill it by weight..the safer method..
.so fill it by weight..only 5 lbs, for the normal sized tanks..THEN you will be okay...you wont over fill it...80 percent of the container full, is considered a full fill....
For the Minto's wheel to work your tanks will be upside down at one point during the rotation..so if they over pressure, they will spray out propane LIQUID instead of vapor...dangerous if sparks nearby..well dangerous if vapor also hits a spark...propane lays close to the ground, it doesnt fly away like natural gas does, okay.
The best tanks to use are the ones for forklifts (if money is no oject, yeah righ!)...but gee they cost so much, when you can buy the 5 gallon propane tanks for $25 all day long...Hmm..$130 for one forklift tank or Five 5 gallon propane tanks for the same price...uh....not a problem doing the math there. The Forklift tank has a vapor and liquid valve, the small 5 gallon tank does not. So when its upside down, and you have removed the float mechanism.
..well it makes the cheaper peopane tank able to move the propane fuel from one tank to the other one...if you leave the float inside the valve..well you wont transfer much liquid and thus your wheel wont work too good, (uh..it wont put out much power, which is the reason for building it in the first place..ha ha)
Oh yeah dont forget for MORE POWER put multiple Minto's wheels on the same drive shaft. think of donuts on stick...uh..just sideways and insulate your water tank so you dont lose heat thru the ground cooling it off. ---------------------------------------------------------------------------------------------------------