Waterwheel Gearing

[dennisbuller]

Hey Folks,

I have been concentrating on a way to harness power from rivers without dams for a while now.

The main issue is one of gearing. With and overshot or undershot wheel we are talking a lot of torque but five to fifteen RPM.

Gearing it up is the problem.

I came up with a design that I call the Pressure Wheel, which uses a spiral pump to change the slow rotation of the wheel into fluid and air pressure.

Great design, but since it uses a turbine to change the pressure into electricity it has to be a fairly large machine to warrant the design.

So back to the drawing board for the homeowner. What the heck, I have just been at it for eight years now.....

The main problem has always been, how do you make a large sprocket for a waterwheel? The Fitz Waterwheel Company cast teeth segments and then bolted them together to make a huge sprocket. To go along with their huge wheels.

I am not forging teeth anytime soon. You probably are not either.

But then I had a thought the other day.

Take a large chain (very large), which is rather cheap, and weld it into a circle. Not that hard, you may have to get someone to cut a perfect circle out of sheet metal to act as a template. And you may have to find someone with a welder....

Then once the chain is a perfect circle, attach it to the wheel, or add heavy sprockets and attach it to the axle. Or both.

I am leaning toward PVC wheels, so I will attach mine to the axle.

To get the gearing multiplication, put two sprockets on each side of the chain in one spot.

One sprocket will have a shaft going to a generator (or another set of gears for gear multiplication), and the other will be attached to the other gear.

In this way the power sprocket will not skip, or push out on the chain axle (the power sprocket should be on the inside, less chance of the chain sprocket deforming).

I have not built a chain sprocket yet. But I have used the two-sprocket method to control skipping and pressure. Works great.

I am going to put a crude diagram of this up on my site if you are interested.

wild water power

-Dennis

[Flux]

Your idea of using the chain as a means of driving a sprocket will work, I have seen it used with the chain straight as a rack and pinion drive for moving furnace doors. I don't know what the losses will be like and I suspect the efficiency and load carrying may be well down on the conventional sprockets but it's worth a try.

Low speed chain sprockets are not very demanding and I have seen perfectly satisfactory ones made by drilling holes in a plate at the correct pitch centres and just shaping the tips of the teeth with hacksaw and file. As long as you can mark out and drill the holes reasonably accurately you can do it with little technology.

Flux

[Norm]

Use large truck tire and wheel, put chain on while deflated....

install chain then inflate tire, won't need too

much air pressure since it won't be supporting

the weight of a vehicle.

[scottsAI]

Dennis,

Chain will work, yet I do not like things that can break.

Replace speed up gears with 60 pole alternator, direct drive.

Requires larger rotor dia and many magnets.

NO gears or chains...

Size is larger than a 4 pole, yet much smaller than water wheel.

Stator Coils don't need to form a complete circle, half or quarter. Fewer coils for single phase.

Cost reducing feature: limit coil sets to get the power/voltage needed from alternator.

Trade off with how many coils needs vs strength of magnets.

Since many magnets are needed, much weaker magnets can be used.

The number of coils required for a given power level is determined by magnetic strength as seen by the coils.

Old HDD have powerful magnets, easy to build up a demo before making the real thing.

Attach rotor to a bicycle to test.

Have fun,

Scott Beversdorf.

[thirteen]

Would a running board installed on the inside of the paddles be ok to put a bike tire on to it and have it hooked directly to an altinator. cogged drive belt on the running board with a cogged bike tire for no slipage. Just a rough idea to play with Cheap and maybe workeable.

[FoolAmI]

Scott,     I've been looking for a 60 pole altinerator or other low rpm 12 or 24 vt altinator but can't find one.       I build water wheels and am trying to put together a simple power producing system for people who have enough flow and head to produce power yet who prefer the beauty of a water wheel over a low head turbine.    

[FoolAmI]

Dennis,      How would your propose attaching this chain to the water wheel.     Spencer

[spinningmagnets]

Scott, do you mean attach alternating magnets to outer rim of water wheel in a full continuous circle of magnets, but make stator only 3 coils shaped like a thin slice of pizza?

[scottsAI]

Spinningmagnets,

Yes, Yes. That's one way to do it. Disadvantage: with iron in the water will collect on magnets.

Or can use two disk with several rows of magnets. (smaller radii disk.)

Coils can be placed all around or a wedge area like a pizza. Will depend on how much power is needed.

Above states it as a trade off between magnetic strength and coil turns total needed.

Multi pole 3 phase alternators connected jerry rigged are no different from a 3*Pole = single pole machine! Yes, by paying attention to the phase and poles can connect coils in series / parallel to meet current and voltage needs.

Have fun,

Scott Beversdorf.

[scottsAI]

FoolAmI,

After watching battle bots I designed a robot, eliminated the chain which seemed to break so often by using many poled motor built into the wheel. Then the show was Cancelled! (Show had been on a while... don't watch much TV.

No 60 pole motors I can find, how about building your own? Design just like used here, yet with many more magnets/coils!

Have fun,

Scott Beversdorf.

[Subman]

You could always use hydraulics. Connect a pump to the 15rpm wheel and connect that to a motor that uses 100th the flow. The pump would pump lots of oil per turn and the motor would need very little oil per turn. The motor would turn proportionally faster.

[Palentier]

I saw this very thing somewhere on the internet the water wheel had a shaft from the center going onshore into a little house / shed where they had a five foot stator with a Magnet rotor the same size.  

Check this link for instructions on building it.  You can do this to any scale you wish.  

http://www.windenergy.nl/website/files/artikelen/AXIAL_FLUX_HowItWorks.pdf

I would use Powdered Iron in the Fiberglass Resin so that the Resin is like a thick paste and you would trowel it over the coils like icing a giant cake it increase magnetic saturation.  This way you do not have to use expensive neodymium magnets you could use bigger and less expensive Ferrite magnets.  You could also sandwich your magnet rotor between 2 stators to double your output.  Really not much on a rig like this that can wear out anytime soon.

Good luck

[REdiculous]

I think hydraulics would be the easiest solution. Choose your oil carefully though.

I like the chain idea too. I saw a picture of a VAWT with that type of setup once.