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Does this concept have any viability?

Does this concept have any viability?

RE: Does this concept have any viability?

hard to follow your problem and your question. it looks like you're running 3 actuators from a single pump ?

another day in paradise, or is paradise one day closer ?

RE: Does this concept have any viability?

actually the reverse .. using higher volume actuators as a pump driving a low volume motor ..

K .. you can stop laughing at any time ..

RE: Does this concept have any viability?

The motor will need low friction seals and ball or roller bearings, but it might work.
Can you get the parts to build a proof of principle thing for cheap?

Mike Halloran
Pembroke Pines, FL, USA

RE: Does this concept have any viability?

When I'm happy with the math, I likely will .. a few other variables to reason out.

RE: Does this concept have any viability?

Looks like an attempt to create a perpetual motion machine.

So no, it has no viability.

RE: Does this concept have any viability?

there are rules about multi-posting. If you want to copy your question into another forum, red flag it, and explain why you'd like it deleted.

doesn't look like a PMM to others ...

another day in paradise, or is paradise one day closer ?

RE: Does this concept have any viability?

I spoke to the moderator .. I did what I was told to do .. I thought ???

No .. I appreciate Conservation of Energy.

What I'm "considering" hence my desire for professional input is to "gear up" a water wheel to drive a PM Alternator.

If I assume worst case I need approx a 1:1000 ratio.

My thought was a multi sprocket drive train or reversed gear reduction unit would present heavy self load losses and high initial break torque. Then there's wear and tear.

Then I came up with this hair brained idea.

Conventional pumps produce insufficient flow rates at low RPMs so the use of cylinders as a pump

Based on just flow rates I "think" it may work, it also offers the advantage of use of hydraulics for other means .. log splitters etc.

RE: Does this concept have any viability?

You have to look at the torque you can get from the water wheel, and how much pressure that translates to.
I suspect that seal friction will drive you nuts, which is why I suggest prototyping one, as cheaply as possible.

Also take another look at roller chain drives. If they are kept clean and well lubricated, they can be very efficient.

Mike Halloran
Pembroke Pines, FL, USA

RE: Does this concept have any viability?

Roller chain was my 1st choice .. finding sprockets of sufficient tooth count to minimize the number "ganged units" has been difficult .. as soon as you fall below a 1:10 ratio it gets ugly. If I could locate a stacked 10T/100T sprocket or could fabricate it easily, we wouldn't be having this discussion. If anyone knows a reasonably priced source, I'm all ears ..

RE: Does this concept have any viability?

Martin Sprocket & Gear goes up to 112T for #40 chain, but does not list a 100T for that chain.

You'll probably have to mount two sprockets on a jackshaft, or drill the hubs and bolt them together yourself.


Mike Halloran
Pembroke Pines, FL, USA

RE: Does this concept have any viability?

Where's the math?

Every inch-lbf of output torque loss will require 1000in-lbf to overcome.

My guess is that you have insufficient water pressure or flow. In hydroelectric systems the generators are driven at their operating RPM directly by a water turbine. I expect that beyond 2:1 to 4:1 the losses are high enough that changing the way energy is extracted from the water is worthwhile over the speed amplification losses.

This is well trod area. Search for "hydroelectric pm alternator"

RE: Does this concept have any viability?

From my various dabblings I'd run a turbine-dc generator, and then sort everything else out electrically, before running a pump or motor for the final output. The reason I say that is that a high speed alternator is easy. DC to DC is easy, using buck boost. And DC pumps are also easy.

In this context by easy I mean there will be a two way trade off, price and efficiency, but conceptually, there is no issue.


Greg Locock

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RE: Does this concept have any viability?

What is your operating working head and desired power out?

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