Does anyone remember / know about this engine.......
Discussion
lufbramatt said:
Yes - I remember seeing this on Tomorrow's World, all those years ago! I remember the same description that you heard too and later, when I came across swash plate pumps as part of my job, I realised that this must have been the principle used in the engine.As I recall, the one they had in the studio was running very fast (20,000 RPM?) with very little vibration and not too much noise.
Looking at the page in the link referenced, it could well have been the Searle Rotocom Engine - it would be around the right vintage, although I thought the one on TW had more than three cylinders.
Edited by Frankthered on Sunday 12th July 11:51
Thank you.
The one on Tomorrows World had a lot of cylinders 16+ from recollection and yes it revved happily to over 20,000 RPM.
The rumour I recall was that it was so efficient the patent was purchased by a petroleum company and then hidden away!
Just wish I could find out more about it, I contacted the BBC but they cannot provide me with any more detail :-(
The one on Tomorrows World had a lot of cylinders 16+ from recollection and yes it revved happily to over 20,000 RPM.
The rumour I recall was that it was so efficient the patent was purchased by a petroleum company and then hidden away!
Just wish I could find out more about it, I contacted the BBC but they cannot provide me with any more detail :-(
https://books.google.co.uk/books?id=HVhlMMQLVhcC&a...
This is the only other information I can find on the Rotocom, but I think the TW engine was probably a development of this - the article states that any number of cylinders could be used.
If, as appears to be the case, cylinder lubrication was achieved by adding oil to the fuel supply, like two-stroke engines, then emissions would probably be a problem, particularly for engines large enough to drive a car.
This is the only other information I can find on the Rotocom, but I think the TW engine was probably a development of this - the article states that any number of cylinders could be used.
If, as appears to be the case, cylinder lubrication was achieved by adding oil to the fuel supply, like two-stroke engines, then emissions would probably be a problem, particularly for engines large enough to drive a car.
Re Rotocom
In 1977/8 I worked for a company called Carawagon in Sunbury on Thames that converted LandRovers and the then new Range Rover into dormobile-type campers. The raising roof design was the brainchild (aka brainfart) of Mr Searle.
Searle was the archetypal mad professor in both looks and manner, he was interesting, driven and completely bonkers. Brilliant as he evidently was in conceptualising he had no mechanical ability, skills or understanding at all. He was hopelessly clumsy and to all practical purposes quite helpless. Nonetheless a delightful man.
Much to the annoyance of the workshop manager he frequently co-opted me to assist with his rotary engine which I recall at the time being labelled the SERA engine - for Searle Roraty Action iirc.
The 'block' looked exactly like the ribbed component in the pic linked above (the ribs pictured are identical to those I saw) and was originally circular. There was a small carburettor mounted on the end of the shaft-stub and porting was as described. Ignition was a small electronic system but I fail to recall the position of the plugs. I do recall clearly the anodised construction of the block which was beautifully made, as was the rest of it (by a specialist machine shop) Even as a 19yr old self-taught motorcycle mechanic I could see that the spherical sealing rings on the pistons were the achillies heel of the device, they had been made from some exotic plastic at ridiculous expense because of the precision of the spec Searle had insisted on for the spherical profile which was apparenty extremely difficult to manufacture. I was also sceptical about the geometry (ie timing if you like) of the piston porting which, despite having specified it, he was quite unable to justify or explain to me in a coherent manner, or even understand how changing it might affect the running (or not) of the motor. He seemed to think that 'it would do' which as anyone who's ever tinkered with 'adjusting' the porting of a two-stroke is very far from reality.
In my time it 'ran' (or rather didn't run) on propane as even Searle recognised that spilling petrol around the place was a hazard. I would spin it up with a black and decker drill while Searle fiddled with carburettor and timing settings. It would sometimes fire fairly consistently but nowhere near enough to be self sustaining. My feeling was that compression was woeful, Searle posessed no awareness whatsoever of the required mixture let alone what was actually being deleivered but felt that if we got it up to 5000rpm it might have run.I also suggested dousing the bores/'rings' with oil to effect a better seal but he was worried the oil would damage the precious spherical seals.
One day I was horriifed to see that he'd clumsily taken a power hacksaw to the beautiful rotor and cut three segments off it to resemble the round-ended triangular shape shown in the combustion-sequence diagram. (Note the detailed diagram above represents the original concept in my time, ie circular rotor). He had no coherent explanation for this but suggested less rotating mass (as if that would make a difference) and reducing heat dissipation. His awareness of the practical workings of an i/c engine were approaching zero.
It was all rather sad, he'd thought up a clever concept , was pouring money into it but had little clue of the practical aspects of realising success.
I'm amazed he was still at it in 1981 when that article was published. Not much development appears to have been made in the intervening years since I'd last seen it.
In 1977/8 I worked for a company called Carawagon in Sunbury on Thames that converted LandRovers and the then new Range Rover into dormobile-type campers. The raising roof design was the brainchild (aka brainfart) of Mr Searle.
Searle was the archetypal mad professor in both looks and manner, he was interesting, driven and completely bonkers. Brilliant as he evidently was in conceptualising he had no mechanical ability, skills or understanding at all. He was hopelessly clumsy and to all practical purposes quite helpless. Nonetheless a delightful man.
Much to the annoyance of the workshop manager he frequently co-opted me to assist with his rotary engine which I recall at the time being labelled the SERA engine - for Searle Roraty Action iirc.
The 'block' looked exactly like the ribbed component in the pic linked above (the ribs pictured are identical to those I saw) and was originally circular. There was a small carburettor mounted on the end of the shaft-stub and porting was as described. Ignition was a small electronic system but I fail to recall the position of the plugs. I do recall clearly the anodised construction of the block which was beautifully made, as was the rest of it (by a specialist machine shop) Even as a 19yr old self-taught motorcycle mechanic I could see that the spherical sealing rings on the pistons were the achillies heel of the device, they had been made from some exotic plastic at ridiculous expense because of the precision of the spec Searle had insisted on for the spherical profile which was apparenty extremely difficult to manufacture. I was also sceptical about the geometry (ie timing if you like) of the piston porting which, despite having specified it, he was quite unable to justify or explain to me in a coherent manner, or even understand how changing it might affect the running (or not) of the motor. He seemed to think that 'it would do' which as anyone who's ever tinkered with 'adjusting' the porting of a two-stroke is very far from reality.
In my time it 'ran' (or rather didn't run) on propane as even Searle recognised that spilling petrol around the place was a hazard. I would spin it up with a black and decker drill while Searle fiddled with carburettor and timing settings. It would sometimes fire fairly consistently but nowhere near enough to be self sustaining. My feeling was that compression was woeful, Searle posessed no awareness whatsoever of the required mixture let alone what was actually being deleivered but felt that if we got it up to 5000rpm it might have run.I also suggested dousing the bores/'rings' with oil to effect a better seal but he was worried the oil would damage the precious spherical seals.
One day I was horriifed to see that he'd clumsily taken a power hacksaw to the beautiful rotor and cut three segments off it to resemble the round-ended triangular shape shown in the combustion-sequence diagram. (Note the detailed diagram above represents the original concept in my time, ie circular rotor). He had no coherent explanation for this but suggested less rotating mass (as if that would make a difference) and reducing heat dissipation. His awareness of the practical workings of an i/c engine were approaching zero.
It was all rather sad, he'd thought up a clever concept , was pouring money into it but had little clue of the practical aspects of realising success.
I'm amazed he was still at it in 1981 when that article was published. Not much development appears to have been made in the intervening years since I'd last seen it.
Edited by Kippermoose on Sunday 11th June 13:18
Edited by Kippermoose on Sunday 11th June 13:20
Edited by Kippermoose on Sunday 11th June 13:24
Kippermoose said:
Re Rotocom
Great stuff
Thanks for sharing that - really interesting insights into a curious looking engine.Great stuff
It wasn't till you mentioned the spherical bearing / seal that I realised what was (a little) different about the engine - it basically eliminated the little end bearing from the con-rod, so had to have, in effect, spherical piston rings to allow the angle of the head of the piston (or pistonhead) to change.
That can't have been helpful for compression. I can't help but think that there are a couple of obvious changes that could have been made to improve things, but ultimately, I think it would only ever be a bit of a curiosity.
Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff