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| The Vapourmotor is unique, as far as I know.
It was my first invention, while I was an engineering student at Southampton University, many (many!) years ago. It's a steam engine...without a boiler. Without any sort of boiler at all! I did patent searches on it as part of the project, but the nearest I could find was something called a flash steam boiler: in this you heat a tube up and pump water in continuously...and high pressure steam comes out of the other end, continuously.
In a sense, my invention took this one stage further: instead of producing the steam outside the cylinder, I made it inside, directly above the piston where it was wanted. The idea was very simple. Heat up the surface of the cylinder head and squirt water onto it.
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Being a student on a very limited budget, it was made out of an old side-valve lawnmower engine which was four-stroke, so I had to make double lobed cams to fit the original camshaft to turn it into a two stroke engine. Then I made a new cylinder head with a sloping outside surface and mounted a large blow lamp above it. The exhaust valve worked as normal (except that it was now two stroke) and the inlet valve push rod worked the injector. You can see the pointed end in the picture below. This bore against the big brass bush, which also had a sloping cutout, pushed the injector valve open, and injected the water.
And it worked! It The pipes coming out of the side went to a pressure transducer and a thermocouple, so we could measure what was happening inside the cylinder head.
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Notice particularly the piston rings in the right hand view; they were made out of PTFE to reduce friction. A tricky piece of turning!
The biggest problem was producing a fine enough spray inside the cylinder: the first injector valve produced pretty much a jet of water which broke up (I think) into big droplets on impact which then fell onto the piston before they had vapourised. Several generations of ever finer nozzles, combined with a "swirler" device to get the jet of water rotating, made the engine run for longer, more powerfully and using less water (we had a flow valve in the line as well). Even so, one could see the cylinder head temperature gradually falling during a run and we always knew when she would finally grind to a halt! Three minutes or so was about the longest run we ever achieved.
It was never efficient enough to be a commercial proposition, and nobody developed it further after I left the University, but when, ten years later, I found myself in the area, I went back t othe engineering department to look up the technician who had helped me build it. Big John smiled, recognising me instantly as I walked into his office. We shook hands and he pointed to a shelf above his desk. 'You'll be taking the engine then?'
I was amazed: I'd assumed it had been thrown away years before. It felt very strange to see it again. He lifted it down, brushed off the cobwebs and smiled at the memory. 'They said it couldn't be done,' he mused, 'so you did it!' t's in my workshop now, beside me as I write this and I still wonder if it could be a safe, low maintenance prime mover to pump water, somewhere remote, where you had a heat source (bonfire, sun's rays, whatever).
Whatever, it provided the inspiration for my first novel "Kicking the Tyres", a tale of motor-racing and women.
| Since then I've invented lots of things, some for companies that I've worked for and some at home in the bath. Many I've discarded as impractical, such as an automatic compass which tells you which direction is best during a sailing race, or simply not economic to make, such as a system to make the model cars actually move along the roads of your model railway (but it was great fun trying!).
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And many more have turned out to not, actually, be new; very often someone, somewhere, has done it before, or something very like it. But a few I've got patents for, and one or two have actually been made, like the high backed Windsor chair with a fold out music stand.
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