New Propeller Innovation: Looking for Comment/Interested Parties

Not discounting your idea .. variable pitch propellors have seen long and proven service in airplanes. ..

2 concerns do come to mind though and would require great attention. ..

Preventing marine growth from interfering with operation of moving parts ..

And preventing cavitation destruction .. the sliding area not being streamlined would causd massive bubles that when pop .. corrode the surfaces. ..

Not saying these issues cannot be resolved. .. but they would have to be for reliable operation

 

Excellent points and these are concerns we share. We think the marine fouling can be overcome- no more problematic than existing rudders and seals on variable props. Even if they were more tedious we would hope the efficiency gains would more than compensate.

The cavitation issues are complex as well as potential vibration issues. The latter can be resolved by empirical testing and real versions would have an engine control unit fed by shaft vibration sensors that allowed the ECU to advance/retard throttle slightly if a vibration danger spot was reached OR the pitch/diameter combo was auto-tweaked to eliminate the vibration.

Cavitation involves banjo music mathematics best applied by hydrodynamic researchers.

We hope that such people will express an interest or that an investor might be enthusiastic enough to pay them to have such interest.

Your comments were very insightful.

Thank you

 

With modern engine control units with pre-programmed operation manifolds, any dangerous combination of rpm, pitch and diameter can be avoided. This is how your car knows when to fire the spark or enrich the mixture etc.

It just needs some sensors and no more electronics than the average fish finder.

Thanks for your comments.

 

Cars don't have propellers, and no engine management will counteract an unbalanced wheel. You seem to think that an average fishfinder is no more complicated than developing this proposed technology. Why do you only provide vague ideas instead of working technology then?

 

All versions exist as CAD models in solidworks. SW is an industry standard CAD package.

Hence the movements displayed in the animations are the outputs from the mechanical linkages in the model. That is, the full range of behaviour displayed in the animation is not just what we imagine but the actual mechanical behaviour of the units caused by manipulating the linkages.

We can't explain the details here since even though patent protection would apply, few investors and researchers would be attracted to IP that has been plastered over the internet.

They would prefer time and space to achieve outcomes and not have an unknown number of people as potential competitors.

Thanks for your questions.

 

Any shaft can have its vibration behaviour changed by changing rpm and in the case of propellers also by changing pitch. This is why propellers on twin engine planes are synchronised by ear or automatically by rpm. Remember that odd vibration that the pilot eliminates as the plane sets into cruise?

Similarly, wind turbines avoid destructive resonance by changing blade pitch and load.

The electronics behind an engine control unit is not complex.

We aren't interested in revealing years of work (although it has been fun!) to anyone with just a curiosity. No investor is impressed by IP that has been splattered about the net.

This technology still needs serious R&D and we're looking for interested parties.

 

So you need an outboard manufacturer to be fishing for this idea and buy your idea then.

Mercury demoed a hydraulic pitch control drive back in 2007.
http://www.saltwatersportsman.com/mercury-s-amazing-new-smartprop

I don't think it ever went on sale yet.

 

So you don't have patents ? That won't impress investors either ! Mate, put your own money where your mouth is. I'm guessing you've been to the bank, and they won't lend on it. I'd say your best bet would be to get it to the stage of a basic working prototype, have some kind of patent protection, and hawk it to existing propellor makers. A thing such as this probably has more application to planing hulls where backing off to hump speeds loads up the engine, it would be nice to be able to decrease pitch when compelled to run at such speeds by adverse conditions. But common sense tells you that no such propellors exist for the great majority of applications, and it is more likely because it is a gnarly problem, rather than one that ingenious thinking has yet to be applied to. I'd imagine there would also be difficulty maintaining smooth operation with the inevitable hard knocks that most propellors encounter, too. Can you utilise a rubber shock absorbing hub with this ? Problematic if not.

 

Also I'm confused by the animation.

Is your prop moving fixed size blades away from the hub to increase diameter?

What's the efficiency cost of the "space" between the blade and the hub?

Does the mechanism in this "space" have more thickness than a normal blade?

 

Excellent feedback and precisely the reason we are promoting on sites like this.

We genuinely appreciate the comments/feedback that has been offered.

I suspect the mercury variable pitch design failed because it uses hydraulics.

Our outboard design uses no hydraulics.

The large boat implementations obviously need it but in the outboard design the forces required to change pitch and diameter are quite low and can be manipulated via pushrods.

Hydraulics are complex, maintenance intensive and can be unreliable as well as expensive. Most people would prefer a direct mechanical link.

For further background that might be interesting to readers, we have not approached the major outboard makers because their treatment of IP is simply outrageous. Below is an extract from the Honda marine website.

Essentially it says "You can send us anything you like, we don't have to acknowledge receipt, if we use it or make money from it then we owe you nothing. Here's the address".

Bombardier (who we believe owns Mercury and Johnson) are similar but don't even have an email address. You send a whole bunch of paper drawings to a PO Box in Canada and again, they don't even acknowledge it ever arrived and as far as they are concerned it is in the public domain.

There are reasons for this treatment (thank lawyers and ambit claims) but no-one in their right mind would agree to this:

--------------------------------------------------
"Because of this, it is Honda policy not to accept any ideas or suggestions submitted by anyone outside of the company. This policy stands worldwide.

If you choose to ignore this policy or are not aware of it and share your idea with us, please know that the following rules will be applied, regardless of submission content, method, media and the response of any Honda employee:

we will not be able to give you any feedback on your idea
you will automatically waive all legal rights to your idea. This means Honda will not pay any compensation, financial or otherwise, if any of our products or services are ever partly or completely the same, or similar to, your idea
we will not consider your idea to be confidential
we will not return any documents you send to us to explain your idea

Still keen? This is the address you need. But by contacting us, you automatically agree to the above rules. And remember, we won't be able to reply

8-1 Honcho, Wako City, Saitama Prefecture 351-0188 Japan
Intellectual Property Division GU Group
Honda Motor Co. Ltd."

 

Ideas that work, sell themselves. Get the thing to the demonstration stage and you may have a chance of getting backers.

 

We have provisional patents in place but our legal advice has been to avoid as much non-confidential disclosure as possible. There is no advantage to us. Like most small startups we use provisionals to test market appeal and after 12 months will make a decision on the full patent strategy. We also have the option of simply lodging a series of provisionals to maintain the IP.

Many investors prefer a full patent to exist but the provisional provides for conversion and the filing date is what matters.

At this point we see no real benefits in building full scale prototypes because their real usefulness only happens when they are tested hydrodynamically and that requires facilities and skills that we don't have. The CAD models already provide a surprising amount of information on stress and fatigue but exploration of cavitation and vibration need more than a Barry's backyard welding job prototype and a CNC produced prototype would be of little use without a cavitation tank and some PhDs in nonlinear fluid flow.

This is why we are also using these forums. There may be people who know people with money, expertise or who have too much time on their hands.

You never know till u try and for us this is all great fun.

The real innovation of the design is that there has previously been no simple, robust way to change diameter full stop- let alone integrate it with pitch control and in a way so they do not conflict. 30 secs thought usually reveals that all linkages will have to co-exist in the hub and then the real thinking begins.

For an example of the pathetic state of the art competition- courtesy of a chinese aeronautical research institute just go here:

https://www.deepdyve.com/lp/institu...n-of-a-variable-diameter-propeller-wmUsYfPZqn

 

I could build a prototype tomorrow but without complex analysis in a cavitation tank it would reveal no more than the CAD model already does and we can email that. The prototype would sit and be captured on video but still wouldn't answer the real questions.

Not all ideas that work are successful. There are innumerable inventions that never succeeded due to timing, politics (the research grant or subsidy ran out) or just were too expensive to manufacture or awaiting better materials technology.

Here's a great concept with significant military funding that just disappeared:

https://en.wikipedia.org/wiki/Baldwin_Mono_Tiltrotor

It's early days for us. We're self funded retirees having fun and in the end most successful ventures will take time.

And even if it doesn't succeed we've enjoyed the whole thing.

Beats dying one day at a time on verandah.

 

Good questions. The blades move radially on their respective shafts. They basically slide in/out under control of their attach points to the hub.

There may indeed be an unknown efficiency cost due to the inner structure that allows this blade movement. We suspect it is far more involved than simple loss of blade area in the inner hub zone. The blade attach mechanisms have fairings on them to reduce turbulence but we suspect that there will be substantial turbulence that only full hydrodynamic analysis in a tank could resolve. These skills and facilities are beyond our level which is why we are seeking collaborators across a range of communication channels.

Note that the aircraft prop animation is a more accurate representation of what is possible since the pitch and diameter control mechanisms are independent.

The marine animation shows the version where changing diameter simultaneously changes pitch. Essentially as the blade moves out it is forced to take on a pitch angle set for that diameter.

 

"With modern engine control units with pre-programmed operation manifolds, any dangerous combination of rpm, pitch and diameter can be avoided. This is how your car knows when to fire the spark or enrich the mixture etc.

It just needs some sensors and no more electronics than the average fish finder."

Cars are Farriday cages and seldom see lightning side flashes.

In FL there are thousands of lightning strikes a DAY.

Many boaters now prefer mechanical engines for that reason.