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Does this concept have any viability

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DBrenchley

Computer
Sep 5, 2016
7
Need to provide a large ratio > 1000x gear up.
Thought this might be a possible solution while offering the use of hydraulics for other purposes.

They always said think outside the box .. wondering if I belong in one .. ;-)

Note this is acontinuation of the discussion in thread2-413973
 
 http://files.engineering.com/getfile.aspx?folder=c476a682-f16a-4053-acd9-ceb57cd06379&file=Hydraulics.pdf
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I'm going to go out on a limb and say that there's a reason that gearing is typically done with gears. Introducing a hydraulic system means a crankshaft, energy losses to heat, potential for leaks, any number of problems. While I'm struggling to come up with a solid reason as to why you wouldn't want to do this, I'm afraid the best I can offer for now is "there is a much easier way". If you're set on not using physical gears, try electrical - a DC motor with a transformer into another DC motor.

As a side note, where an electrical coil or a hydraulic motor can often be used as a generator or pump, hydraulic cylinders typically aren't used to generate fluid pressure in the system and drive something else. That is, they're typically an output device, not an input device. Technically they can be used for that purpose, but I would imagine those units are designed differently for that purpose.

Cheers,
Nate
 
yes, hydraulic cylinder are not meant to continuously pulling and pushing where you have to consider the life limit of the seals due to friction (even though it is oily) and heat due to the hydraulic oil and the friction itself. Not sure how big is the physical size of the cylinder but you may require more space than a hydraulic pump.
 
You seem to be a long way down the path to a solution without actually stating the problem you're trying to solve. I'm sure it is clear in your own mind, but less so for us!

If you're looking at this machine as the prime mover for an electrical generator, which seems to be the way discussion went in the other thread, how about starting by stating what you have available to drive the generator - flow and head? High head, low flow would favour an impulse-type turbine, while low head, high flow would favour a Kaplan turbine. Both are well-proven and efficient designs.
 
As drawn, your motor doesn't work. The fluid flows through the check valves on the left and continues through the check valves on the right and back to the pump.

To create a working motor from cylinders you need to synchronise the admission of fluid to the motor shaft.

Why do you need to create a new type of motor to solve your problem? Motors with very high torque and low rpm are available off the shelf.

je suis charlie
 
Gruntguru, actually you are incorrect. The Hydraulic pump you mention is actually the motor being driven, as it says 'output'. so the layout of check valves would work...

So theoretically this could work, but practically I think not.
 
Should work. What you have is a multi-piston pump made of discrete components.

Ted
 
Thanks guys. I just noticed the first post says "gear UP"

je suis charlie
 
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