Green Steam Engine

Dave,

Put Swash plate or wobble plate pumps and motors into Google, this is not a new idea.

I particularly like that he expects all the punters to pay for a licence to build one.

Play "I betcha" ?

It's a neat enough design, and would look good on a tabletop, but I would not hold real high hopes for longevity in real use. Maybe I'm wrong.

Cheers Trevor Jones

Warrington

Hi Dave

I happen to have in front of me a Siemens engine design of about 1860 with the same layout (with 4 cylinders), the only difference is that this one uses a bendy coupling, whereas the 1860 version used a rigid coupling with a ball pivot in the centre. As far as I can see, anything else claimed (and there is a lot) is either baloney or irrelevant to the patent, which is just the bendy bit. Siemens was trying to invent the IC engine, the drive system wasn't the novel part of his design, it probably dates way back to the days when there was a patent on the crankshaft.

Steve

Warrington

This cropped up 6 months or maybe a year ago, I imagine his later development will be a Perpetual Motion Machine coupled to an anti gravity system for time travel.

Curious perhaps it is, cheap, reliable, efficient or ecological etc it ain't.

Richard

Warrington

> Hi Dave

as a matter of interest - on what basis is it NOT cheap, reliable, efficient or ecological?

Dudley

Purely on the basis of Carnot's theorem - an engine running on low pressure steam at low inlet temperture can never be more than a few percent efficient given that the exhaust temperature has to be above 100C and the inlet temperature is probably not a lot higher.

Am I missing something, or is the bendy bit actually superfluous ? And I cant see how having a spring being bent like that would contribute any return of energy.

Dave

Warrington

You are right, the bendy bit returns no energy. The mechanism doesn't have the friction that might arise in a ball swivel, but the main thing is that it might just be novel enough to gain a patent, unless you can show someone used a bendy rod before. To patent something it doesn't have to be useful, just novel, and on your own web page you can claim anything else you like.

You don't even need a patent, but some people will add one to the other and think the patent backs up the misleading claims - which it doesn't - it just applies to the bendy bit.

Max efficiency of a heat engine is temperature difference divided by the higher temperature (and we are talking degrees absolute here). Minor variations in friction within engines is tiny compared to that fundamental limit.

Steve

Warrington

Its amazing how much money people must have spare. Patents are not cheap (Ive looked into it for something Im developing), and whilst using a spring might be 'novel' the engineer in me cringes at the claims on the website.... Ive not built a swashplate engine, but I cant see how you even need the 'bendy bit' There must be a pivot / bearing in the flywheel, which has to take the thrust. And as for not needing 'crossheads' whats that bolted to the back of the cylinders?

Dave (glass of wine in hand, grumpy old man hat firmly on!)

Warrington

Hi Dave,

I like the grumpy old man with glass of wine attitude - can go for that myself.

I have bunged a copy of the Siemens engine drawing from 1860 on the web at

snipped-for-privacy@btinternet.com/Siemens/SiemensEngine1860.jpg

You will see the similarity (assuming the link works)

Steve

Warrington

>

Isn't the Bendy Bit the steam pipe from the valves in the flywheel? For more swashplate engines see "The Knife and Fork Man" by Bill Fairney,its the story of Charles Benjamin Redrup. Jim Lugsden

On Thu, 6 Mar 2008 21:52:59 -0000, "James Lugsden" wrote, in impeccable English,..

Warrington

>>

Also see David Urwick, patentee of the triangular gib key and designer of the Metalmaster machine tool. His passion was stirling engines and the last one I saw described in ME was a Siemens Drive with lots of tiny ball joints. He'd used all manner of devices from z-crank, swashplate/wobble plate and lots of others in earlier engines. Just not content to watch wheels go round, that man.

On Thu, 06 Mar 2008 23:55:14 +0000, Ray wrote, in impeccable English,..

Following up self, just found it

Ray,

Love the equation for the pizza, but was surprised to hear about this being referred to as the Siemens drive, and I am also not sure if the correct term is swashplate as I thought that had a sliding angled plate, whereas this more of a wobbler.

Back to the Siemens drive..I came across the design of this engine in a book called The Theory of The Gas Engine by Dugald Clerk published in about 1882 (though possibly reprinted from an earlier magazine). It is interesting in stating the Siemens had worked out all about the need for compression in the cylinders by 1860, and then built the engine in the drawing (for which I provided a link in an earlier message). Clearly Sir/Dr Siemens was at the leading edge of the theory, and I have extracted this bit...

"With reference to the early engine which Dr. Siemens constructed in

1860, the author had stated that it combined other elements, which were entirely wanting in the gas engines of the present day. The gas engine of the present day, taking either of the three types, was, in his opinion, in the condition of the steam engine at the time of Newcomen."

"In the engine which he constructed in 1860 all those points were fully taken into account. The combustion of the gases took place in a cylinder without working a piston, and in a cylinder that could be maintained hot, and the gases after having completed expansive action, communicated their heat by means of a regenerator to the incoming gases before explosion took place. Although the engine was not worked with ordinary gas used for illumination, but by a cheaper kind made in a gas producer, he then thought that a gas engine constructed on that principle would prove to be the nearest approach to the theoretical limits which could never be exceeded, but which might exceed the limits of the steam engine four or five fold. The engine promised to give very good results, but about the same time he began to give his attention to the production of intense heat in furnaces, and having to make his choice between the two subjects, he selected the furnace and the metallurgic process leading out of it ; and that was why the engine had remained where it was for so long a time."

So - the big item here is that there is not even a mention of the drive system - not a peep. So although we know Siemens had it as part of his design for an internal combustion engine he built in 1860, surely it would have been remarked on if it was novel. I suspect it had been around for some time.

Steve

On Fri, 7 Mar 2008 15:16:36 -0800 (PST), Cheshire Steve wrote, in impeccable English,..

I forgot where I pinched it from and it's getting boring now.

I'm not sure either. Mr Urwick called it a nutator, attributing the basis of the idea to Siemens' work.

The Green engine has perhaps a slightly novel feature in that the cylinder block itself moves in a cone-like motion, obviating the need for jointed connecting rods. The cable looks a bit like a Hillman Imp gearshift rod coupling.

A step further might be to rotate the block with the shaft as in Rexroth bent axis hydraulic pumps.

Some models offer variable capacity by straightening out the bend. Porting appears to be simple by comparison :)

Ray, I had overlooked the fact that the cylinders move. It would appear to be a blessing as regard the linkage, but a nuisance as regards balance and the connections for the inlet and outlet. I have had no success in find any earlier example of the 'Siemens drive', but have found the swashplate principle illustrated in a list of mechanical movements from 1842 - that mechanism may date back to antiquity. There is much in the original Siemens engine design that I do not understand from the drawing. I wonder if the patent is available somewhere, or whether some ancient text gives more details of this experimental engine.

Steve

Is there another steam engine that is as light for the power?