A Promising Evolution in Engine Design - The Coates Spherical Rotary Valve
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- Опубликовано: 8 июл 2024
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On this channel we love engines and anything that can further engine technology. Now the other day as I was reading thru articles I came across this really interesting new tech that is supposed to replace your conventional poppet valves with a new Spherical Rotary valve train. Now if videos like this peak your interest you why don’t you sub, its free, and if you later decide you don’t like me you can always unsub. Also watch this video till the end, because at the end there is a little twist.
Anyways Before we get into this new technology lets first talk about conventional engines, how they work and how we got here.
Over the years Engines have undergone remarkable advancements, with the valvetrain playing a critical role in power generation. Conventional engines utilize poppet valves and cams to control airflow and combustion within the cylinders. So how it works in most engines is the poppet valves act as the primary means of controlling the intake and exhaust processes. These valves are opened and closed by camshafts, which are synchronized to the engine's rotation and controlled by a timing belt or chain. The camshafts have lobes that press against the valve stems, lifting them from their seats to allow the intake or exhaust gases to enter or exit the combustion chamber. This synchronized action, coordinated with the engine's rotation, ensures precise timing and optimal performance.
But they aren’t perfect, you see Although conventional valve trains have served the automotive industry well, they have inherent limitations that restrict their performance potential. These limitations include airflow restrictions, limited valve lift and duration, and high operating temperatures. As a result, conventional engines face challenges in achieving high compression ratios and maximizing efficiency.
However, the Coates Spherical Rotary Valve Engine represents a groundbreaking leap forward in valving systems, boasting unparalleled breathing capabilities and efficiency. You see This advanced engine utilizes a unique valving system based on two spherical rotary valves mounted on separate shafts-one for the inlet and one for the exhaust.
Now One of the most striking advantages of the Coates Spherical Rotary Valve Engine is its exceptional breathing capabilities. Comparative tests have demonstrated that the engine can achieve nearly double the airflow of a conventional poppet valve engine. For instance, a five-litre poppet valve engine recorded a reading of 133 cubic feet per minute (CFM) when fully opened, while the Coates Spherical Rotary Valve Engine of the same displacement achieved a reading of 319 CFMs-an extraordinary advantage in airflow performance. And remember with engines the more air you have the more power you can make, that’s why forced induction is a thing.
So how exactly does this thing work? Well the Coates Spherical Rotary Valve Engine operates under distinct parameters that contribute to its superior efficiency. The valves rotate away from the combustion chamber, venting and charging on the opposite side of each sphere. This design also effectively lowers the combustion chamber temperature, enabling the use of higher compression ratios. Compression ratios of 12:1, 13:1, 14:1, and 15:1 have been achieved, depending on the application, further enhancing the engine's efficiency.
Now you might wonder, how does this thing seal, and also what stops it from wearing? Well the spherical rotary valves operate on ceramic carbon bearings, eliminating the need for oil lubrication. They do not make contact with any part of the housing, thereby minimizing friction and wear. The valves are equipped with floating-type ceramic seals and two piston rings, housed in small cylinder-type chambers. Activated by the compression and combustion strokes, these seals ensure 100 percent sealing effectiveness when compressed, promoting optimal combustion efficiency.
Now all this adds up to better performance out of your engine, you see The Coates Spherical Rotary Valve Engine's exceptional design and unique operating parameters result in extraordinary performance figures. Comparative tests conducted on a dynomometer have shown significant advantages over conventional engines. A five-litre ford small block poppet valve engine, operating under the same loads and conditions, produced 260hp and 249 ft ibs of torque on the dyno at 5500 RPMs. In contrast, the Coates Spherical Rotary Valve Engine reached an astounding 480 BHP and 454 foot-pounds of torque, Furthermore, according to the company them selves the lack of valvetrain limitations allowed the engine to spin all the way up to 14,750 rpm.
#internalcombustionengine #rotaryvalves #freevalve
I remember reading about rotary valves decades ago in Popular Mechanics, Smokey Yunick was playing around with them. The inherent problem was that while poppet valves seal tighter when subjected to pressure, rotary valves suffer from blow-by. Similarly, poppet valves have no problem with thermal expansion and contraction, but rotary valves very much do.
The sealing dilemma of this rotary valve design is obvious. With compression, conventional valves wedge tighter into their seats, and continue to bed as they are run in. Ever since unleaded gas required better valves and seats, conventional valves with just regular oil changes and belt maintenance commonly go for 100,000-250,00 miles with no issues--- frequently still passing emissions tests with like-new performance. These?
These are all issues poppet valves suffered in the early days - the real reason they are not developed further is, whats the point? All manufacturers know that ICE engines are history so why spend billions making a better one?
@@piccalillipit9211 Good point, though I suspect -- I'm not a mechanical engineer -- that the basic physics of increased pressure naturally sealing poppet valves tighter but doing the opposite for rotary valves, is a fundamental problem. Regardless, I think you're right, it's probably an irrelevant point because the writing is on the wall for ICE engines.
@@tinetannies4637- Yeah I think if they wanted to make it work they probably could. Im increasingly of the opinion that as good as electric cars are, they are not the solution. IMO - Some people need electric cars. The majority of people need excellent mass transit, busses, trolly busses, trams, light rail and high-speed rail. And some people need ICE engines that are high quality and efficient.
But we are all suddenly obsessed with battery cars.
@@piccalillipit9211 Sensible logic, I suspect you're right.
I remember reading about these Coates valves in the 90’s. If this design has been around so long, why hasn’t it shown up in the mainstream? Still has sealing issues inherent to rotary valve design.
Even if it seals well indefinitely, the performance gains will never outweigh the manufacture cost. Carbon seals, ceramic bearings, extremely precise spherical grinding... Nah, cams and valves. DOHC with VVT comes very close in performance for a fraction of the cost.
IIRC, Coates wanted a LOT of money for rights. The Japanese automakers were interested regardless. However, Coates wanted the product to stay in the US, with US automakers.
Same reason Wankels are so dirty. Corners present greater surface area, cooling the mixture below combustion temperatures. Look at the intake and exhaust ports in the illustration; 'way too much corners for a clean burn.
@@Cheezeball99999 ya beat me 2it, took the words right out of my mouth 🤔 cool idea though, I was always partial to the OPOC engines.
Mazda has made continuous improvements on their materials, so the rotory valve is not necessarily a dead end
In the early 1960s a company called Southcotts built a rotary valve head for a 6 cylinder Holden motor. This motor was raced in a speedway midget with moderate success , but sealing prevented it from achieving its potential. There are pictures on the internet look it up. PS I lucky enough to see it race.
That Holden motor needed a supercharger so it could get the air into the cylinders, as I remember. A guy named Dunton was involved in the design & building of the project.
I actually do know a little bit about Coates International. I worked on a team developing cylinder heads valve covers front covers and intake and exhaust manifold at a foundry for an 850 in.³ engine line 6 engine with coats spherical valve technology. I have met George coats personally and done a tour of his shop. This technology is not phony, but I am aware of how big business are looking to buy the technology so they can shelf it. Coats wants his technology to be used all over the world. That is why he will only deal with businesses that will buy a license and pay a per engine royalty of $50. This way he can guarantee that the technology is not buried.
That is kind of strange, I was doing it in 1974.
And I was doing it in 1970 with a Kawasaki!
Thank you so much for your post. Sincerely!
That head assembly is HUGE!
24v vr6
Big head means big air flow.
actually depends on design but generally rotary valves are smaller.
I remember reading an article about this valve system back in the 90's, and expecting a revolution in engine technology, but it never arrived.
They sold out to the Chinese
Yeah, it never will arrive because it is practically inferior to poppet valves.
That's about how old the video looks.
It's a conspiracy by valve and spring manufacturers. They squashed the patent 😂
@@geniferteal4178 Bullshit
Driving4answer made a great video on this subject, he said that it's shortcoming are that it don't seal the cylinder properly during it power stroke therefore losing power
Driving4answers is an idiot.
Except this does not operate with a same principle. The rotary valves on his video had inlet and exhaust port channels going through them, that is not the case with these spherical ones.
Doubling horsepower doesn't sound like losing. If they make it legal on indy cars and Nascar it won't be long before someone figures out how to fix the blowby problem. There's gotta be a way, some type of clever groove or chall or something. There's gotta be a design solution.
I remember reading about this , probably in the late 90’s in Hot Rod or perhaps Popular Hot Rodding. Always wondered what became of this technology. Guessing that there are sealing issues that arise after some time, similar to the Wankel….
Sealing issues were solved by the 90s. The guy worked on the design and the seals since the mid 70s. Finally found a carbon/bronze ceramic seal that worked.
When I was a teenager I came up with this system then later found out someone else already created it...damnit
More engine technology I've never heard of. Where the hell do you find this stuff! Seeing how the rotary valves work, they are almost common sense. I'm surprised they haven't
been put into use. Keep these excellent reports coming.
I would call this valve body the "super Hemi-head".
Cost of licenseing limit wide spread adoption
Maybe because of the patent and their rights to the design.
They haven't been put into use because it's a failed concept lacking adequate airflow with poor combustion efficiency and it's heavier and considerably more expensive than a traditional setup that makes more power, is cheaper, and weighs less.
@@steveletson6616That's a funny way to tell that you didn't watch the video nor the video from driving 4 answers about (barrel shaped) rotary valves.
Coates Cylinder Head company had a lot of Enemies! I was asked to be a bodyguard in 2001 !
I can imagine they would have had enemies, should have just gone ahead anyway in an undisclosed location
Same enemies as the improved/upgrade carburetor creators had. Same reason why the original job formula of slick 50 is no longer legal in the USA
I can only imagine the troubles, much like Tucker had trying to break into the industry with all is groundbreaking technology at the time.
@@jamesharrison6201 I use to use Slick 50 in my 82 Ford 5.0 (302ci) engine which has 372k miles and still passes Cali smog test. Owner since new... 42 years daily driver!
Ah yes, my favorite type of valves/cams. Just imagine the Chevrolet 496 or Toyota 2JZ with these things 😍
It’s simple ?
Imagine a 3800 cc with this kind of valve train with a supercharger. With NO valves to "float". No wonder it can rev so high!
Original development was on a Chevy big block
@@asherdie wish they had a video of that
or my lawnmower :)
These heads are more than 25 years old. I used to read about them in hotrod magazine back in 2000. They were a few years old then.
I saw one of these engines in the 1970s in a model airplane.
Yes, Coates had been working on the design since the mid 70s.
Look up Ralph Watson in NZ. He converted BSA engines. He raced them.
Ralph Watson nz
I actually emailed Coates 15 years ago and he replied…
He started out in the early 60’s !
Sometimes an idea is too good. Sometimes the forces that be fight against good ideas. After all, how many stories have you heard about carburetors that produce 100 mpg only to completely disappear and the inventor with it!
Do we know any of the names of those inventors or have and pictures of what they made?
@@90ForLifeTeam A car can easily get 100 mpg. The problem is it will suck at acceleration, have minimal load capacity and just be too slow for road use. Conspiracy theory believers are Not the sharpest tools in the shed.
In the 70s, I saw a rotory valve in a model airplane.
I wonder if that was Coates himself.
I love how the promo video of poppit versus rotary valve power comparisons shows a songle carb versus a four carb setup. Not to mention the rotary valve would also cause a different manifold design thus changing even more variables.
Simple reason is the poppet valve engine can't flow more air than the single carburetor can flow. The rotary valve engine has much higher air flow and the carbs and intake then become the limiting factor. If you restricted the air flow on the rotary valve engine of course it wouldn't make more power but that would make no sense whatsoever...
@@kennethney4260 and if you had oversized valves coupled with ported manifolds you would also get higher increases in horsepower. My point was they were comparing two completely different setups rather than comparing air flow numbers.
The reasoning you use to convince people to subscribe to your channel ( and if they don't like you, to unsubscribe) was enough to persuade me to subscribe, before even watching your video! 😁
It probably won't meet a emissions standards would be my guess and the manufacturing costs is super high I would Imagine
The 80 cc Yamaha 2-stroke motorcycle used a rotary valve setup . I owned one for a short while. It was short on power, but ran smooth.
Lots of potential in this project.
I have a sketch of a type of rotary valve head design that can use cam timing and the amount of open time. The key to my design is that the rotary valves don’t rotate 360* but act on a cam design that opens and closes the valve with 1/10 the weight of a conventional valve spring. No patent yet but would like to experiment with it first.
This has been around for years, I recall seeing a yt vid on it at least 15 years ago. And other manufacturers experimented with it in the 1950s, one of which was Norton motorcycles. I always ask myself why it's never been adopted by the racing world as they are are constantly looking for a competative advantage, especially in F1. One reason may be that they now use electronically controlled solenoid valve actuation, which means valve timing and opening are continuously variable, so the advantage of rotary valves may not be worth the cost.
About time valve technology moves forward. Seems this idea took a backburner from years ago. Finally things are going forward. Way to go COATES !!!!!!!!!!!!!!!
The problem is that this thing runs no better than a conventional 5.0 Ford can .
The rotary valve uses way less energy than a regular valve. This is my belief. @@petemcpeterson6205
I first saw the coates design more than a decade ago, and this design first popped up in the 1920's or 30's, and it has gone nowhere meaningful since then. If this was really a revolution in engine technology there has been ample time for it to be adopted industry wide. The fact that it has languished in obscurity for almost 100 years is enough evidence that this is not the revolution that some think it is.
Well stated logical deduction Matt. But I seen a racing engines side by side one tappet one rotary. The rotary outperformed the tappet. The problem is I do not remember by what amount of extra power. Sorry Matt. @@mattzimmerman5967
It is going nowhere. It is junk.
Am amazed we quit hearing from the Coates engine, sounded like a good alternative to the valves today.
Not sure if it was a scam, but hey, there are so many out there, not only in the automotive world. Cheers!
China bought them out and now licence use.
Got to wonder what happened behind the scenes
As I posted elsewhere, rotary valves suffer from blow-by and thermal expansion/contraction, two things poppet valves are inherently immune to. Poppet valves naturally seal tighter the greater the pressure. Rotary valves, on the other hand, behave the opposite.
I find it highly unlikely that a SB Ford held together at 14K RPM.
You would be highly WRONG!
@@Axeman428 Tad aggressive, but tnx for setting me straight 😉
Progression of the aspin valve from the 1930s. The only efficient rotary valve engines that I can think of are two strokes using disc valves. Rotax 256 and it's variants - 100hp from a 250cc engine.
Keeping it mechanical while improving performance and lowering emissions. The rotary valves are definitely my favorite kind of valvetrain for engines ⚙️
There's no proof any of those things are true.
Like the dreaded apex seals
0:20 Chris, how can anyone not like you? Can't imagine that!
I remember seeing this technology in a Popular Hotrodding Magazine in the 1990's and there was an actual name other than Cotes attached to it, That name was Ryan Falconer. Ryan was an engineering maverick that specialized in gas engines and was always trying to improve efficiency (Efficiency=more performance that can be obtained). He's known for some engine designs that were either used or considered for indy, A V12 as well as a 3 cylinder harley based engine, one of which was put in a custom chopper for the Great Biker build-off series
Have you looked at the Bristol Centaur Aircraft Engine that powered the Hawker Sea Fury Aircraft at the end of WWII and through the Korean War for the British Navy? It was touted as the epitome of technology in Reciprocating Aircraft Engines before they were abandoned in favor of Jets. It was a very powerful .Radial planform engine. I am not clear on the exact engineering of the valve train so cannot compare it to the Coates.
This is more what I had in mind; but i never thought about capturing the charge in the shaft to wait for a piston cycle. Perhaps it's just best suited for forced induction 2 cycle applications.
I remember thinking about rotary valves around 20 years back and telling an engineer friend, and he showed me the Coates rotary valve sytem on the interweb, surprising they have not made more headway since then, seems all is not kosher with them.
Coates had a building in Wall Twp ..I visited their shop in the early eighties..what’s amusing is their shop coats…somewhat pompous..but what caught my eye is the bicycle cable that was their throttle control…it’s just flopping around
At that time ad when your video shows the only production format.that accepted their design was the ford small lock because no center head bolts…such as Chevrolet
At that time I owned Performance Racing Engines in Point Pleasant Beach and visited their shop….nothing was going on and the limited equipment was a Tree milling machine and a lathe the dyno was what you show as is the Coby throttle
A lot of undocumented claims were made but as I offered a mustang chassis to put there mule into the car for some 1/4 mile drag tests….they denied and at that time were only talking about ceramic spherical seals
They were also looking at the Mercedes twincam inine engines because of the permitter head bolt arrangement.but I don’t think it happened
One of the big heat input in engines is the valve train, roller lifters and roller bearing rockers have helped eliminate some of the heat output, but spring pressure for seating valves also creates heat. A rotary valve would need to seal of course, but just like poppet valves they would need to be able to transfer combustion/ compression heat away from the actual part to maintain thermal expansion and not overheat. Likely a lot less friction loss , less energy to operate , higher flow all contribute to higher efficiency. Sounds like a great idea, just get it implemented.
14:1 is still done with traditional valve designs. It’s just more common in a motorcycle engine than a car engine. But even the Mazda Miata engine has a 13:1 compression
There have been a number of rotary valve designs over the years, a conical one with the axis inline with the bore, a cylindrical one across the bore like the Coates and of course the sleeve valve. They all develop more power and are smooth but they also all have problems with combustion chamber shape and oil consumption as the rotary valve must be lubricated. Coates and others have tried ceramic bearings but like ceramic pistons, this never quite works. With all rotary valve designs the lubricated surface is open to the combustion chamber at some part of the cycle so oil gets burned. But look at the freevalve technology, it too promised much but a few years on we are not seeing it in widespread use. Poppet valves are not ideal but they are well understood and they work well enough. We know how to build DOHC variable valve timing engines, (I drive a 30 year old Mercedes with this tech) but what engine does everyone want to fit, an LS, a push-rod engine!
Excellent response thanks. Poppet valves also don't have issues with thermal expansion and contraction the way rotary valves do.
Sealing the air inside the combustion chamber is an issue. Air leaks out of the valves it’s a great idea and maybe some day they’ll have a material that can seal better
I suspect blowby problems when idling and cruising
The reason it didn’t work is because the rotary valve is like a rotating drill bit and at the point where cylinder pressure is sealed the constant rotation quickly wears that seal and you began to have cylinder pressure leaks . The standard tapper valve statement does not exhibit rotary wear on the seal surface and so it has the longevity needed for 100,000 plus miles. Among other problems that I don’t feel like elaborating on here
Every one says "COSTS" they forget just how much COST went into getting the IC engine where it is today! That compared to the production of parts that are considered too expensive today, consider the "Cost" of research/machining development that went into the final Merlin aircraft engine!
I love the clips of Mazda RX7's using rotary *engines* in this vid. LOL
I see a couple issues right off the bat: First, keeping that rotating valve assembly lubricated will be a chore. That's a whole lot of friction surface in the hottest part of the motor. Second, although a turbo can solve the problem of air volume on the intake side, the exhaust side will need a rotating chamber volume at least equal to that of the cylinder volume, or else you are compressing the mix twice. Such a volume would make the head assembly so freakin' large that it might make the motor impractical.
I like their concept!
I have seen a motocross engine, that was 2 stroke 1 cylinder that I think bombardier made. It had a single spinning plate for intake and exhaust. The engine was open and was being worked on at the time. Iwas told it could reach rpm of well over 10,000. I would say it was in the early 80s. I though that was very interesting at the time, and still do.
Same thing with Koenigsegg free valve technology. Development of regular valves tec moved along so well it effectively eliminated all contenders
Apart from the sealing issues, I remember reading or hearing about the airflow eventually choking itself at higher rpm's due to the speed of the air reaching Mach speeds. Not sure where I heard or saw this, but it has always stuck with my memory.
Sealing is complex on these rotary valve engines. . Slight combustion pressure is lost but can be overcome. .I think durability and cost is a factor why we're not seeing these engines
I actually had the exact same idea back in the late 60s (I was 12), but nobody took me seriously, and I didn't have the means to develop prototypes. But I did do research in the US Patent Office, and grew convinced that nobody else had a patent for the same idea. Now that I'm nearing retirement, I suppose I should pay them a visit - - just for the bucket list.
Sure Jim. Sure you did.
Coats International website is still up must be in business , it looks like they went into industrial market .
That spherical rotary valve assembly looks hefty to suggest parasitic energy losses from inherent inertial disadvantages. Improved power, efficiency and heat dissipation advantages can only be offered at a constant engine speed but not in real life frequent engine speed change scenarios. The increased inertia of this system will requires more power robbing low to high engine speed shifts which in real street or track driving will translate into worse acceleration performance, more heat retention once the 'deep'heat sink' assembly becomes saturated, and less efficient energy draws when repeatedly going from slower to faster speeds. This system would be more suitable for high rpm drag racing combined with heavy clutch construction.
Every technological problem can be solved, ( time, money, and effort). Rotary engines have come a long way, as well as hydrogen power, and look at the strides that toroidal props have made. Shout out for all the "backyard " mechanics that keep on keeping on!
This thing has been worked on for over 20 years. I was impressed, but it’s never gotten past prototype stage.
cause rotary designs are not sealing well. This is why they were abandoned.
I remember reading about this tech in the late '70s. Still haven't worked it out?
I read about these type of valves in the 1970s just out of high school. Evidently they were not reliable enough for production. Maybe they’ve improved them by now.
The crankshaft in 2-stroke rc glow engines operate very similar to this.
I wonder what the fuel consumption of the Coates design was in comparison with the "normal" engine. The Wankel engine was also great in theory but in practice the rotor tips wore and fuel consumption was a BIG problem
I first saw this type of technology back in the early-mid 1980's, don't remember the developer but it seemed as though the initial problem had to do with carbon buildup on the lobes and causing failure of the sealing ability. Maybe it would be better suited to a gaseous type of fuel such as propane. Is a shame that it can't be resolved as it would simplify the valve train assembly quite a bit.
well you are certainly right about the poppet valves being a really weird thing. I know that Kawasaki used a rotary valve in some of their two strokes back in the early 70's, the valve system worked but the bike had so many other flaws that the value of the valves was easily over looked (noteworthy problem, the ignition sparked sometimes and was only loosely connected to the piston movement). Now as far as this goes, it looks to me like the design of the compression chamber might have been part of the problem. The sharp edges of the ports would certainly cause detonation (I might be wrong but I do not have a good design blue print). Still the piston engine needs better valves. The two stroke diesel idea using spark ignition (mazda and others) seems worth more effort and some kind of 4 stroke application might work out. See 'Driving for Answers' for further discussion
I remember looking at a video on these valves in automotive class back in 2002. They had a Harley Davidson with these rotary valve heads and a few four cylinders and the V8 small block as shown. Cool design but i guess the valve isn't cost effective to produce.
would be interesting to see if these can be set up for cross-flow in naturally aspirated situations
319 CFM is inline with what modern dohc heads can flow. Ie k20,vr30 , b58 , coyote gen2-4.
I remember they had these in mystangs and harleys
The desmodromic valve system used by Ducati while not rotary does get rid of the springs,
Others below have commented that this isn't a new concept, which doesn't mean it isn't a good idea, but I can see problems that need to be overcome, some of which may be insurmountable. There is one advantage--valve float at high rpm would be eliminated. In the past I've worked on evaluation of alternative engine concepts, and quite often new concepts serve to illustrate the advantages of current practice.
Interesting idea. I'm not convinced, yet, that the benefits of a spherical rotary valve over a cylindrical rotary valve would justify the higher production cost involved.
I've actually got a pre patent on a valve design like this from the early 2000's
Patent Number?
Coates sold kits with the heads and they were expensive so not many were sold. He preferred selling complete engines.
This concept has been around for decades, but at present the complexity of the components and the materials required simply make it a good idea but to make it mass production cost-effective simply isn't there.
rotary valves will leak like crazy
Yeah I went to visit back in the day and we never seen any engine on the street or car show
Very interesting.
Well this technically is old, but perhaps technology has advanced enough that the leaking and blowby on the combustion stroke can be eliminated or reduced enough that it isn't an issue. If you look at it, it seems like a great idea since the energy used to open poppet valves is a drag on the engine, plus cams, lifters and valves do fail and can cause catastrophic damage. A rotary valve system would greatly reduce the parasitic losses and eliminate catastrophic engine failure when the valve train has a failure. Hopefully material science can make this possible and prolong the use of internal combustion engines in vehicles for longer with reduced need for fuel and less emissions.
There is a guy on the BMW forum that had also designed a rotary valve for his BMW inline-6.
Any more info on this??
Yep I just found it
ruclips.net/video/vpEV_uX1zf8/видео.html
@@ChrisVSCarshe's here on youtube too, just search "rotary valve e36" and you'll find a lot of videos
Do you have a link for that info ?
I guess that a rotary valve applied to a compressed air engine would avoid most of the problems in an ICE which are primarily from combustion heat and pressure, and lubrication oil being burnt.
I think you lost us there, what's a compressed air engine...?
@@paradiselost9946 ah, compressed air…. vehicles have been made with it, but they don’t run for more than a half hour….
@@PRH123 i like the "half an hour"... rather generalised, isnt it? no other option, say, bigger tanks or smaller capacity engines in that general statement? its always 'half an hour"?
and you missed the main point... ALL IC engines are running on compressed air. they just add fuel, ignite it, thus raising the temperature of that air.
that as per charles law, increases the pressure of that air. which can then deliver more work than it took to compress.
engines dont run on fuel. they run on AIR and HEAT. heat most often being obtained via the combustion of a fuel.
Bultaco bikes tried this loong time ago, and sealing was a nightmare, they ended up injecting oil between the "valves" and the casing, what make it burn oil, hard to think it passing emissions today...
Yes I've heard of it too and seen it on magazines it's a shame that's faded off
One of their main focus was in the diesel industry. Cummins, 60 Detroit
Sleeve valve engines have been around for over 100 years, and do well with lower compression but the real next big devepment is for camless electronic poppet valves.
I would think that super charging and or turbo charging is cheaper and better whilst achieving the same result. To be better than existing the new equipment has to have a number of better advantages all at the same time.
A guy in the uk built a historic race car running these valves and used them successfully. This was before this company. He passed away however his car is still going and still in use.
The car with the BSA 90-degree V-twin in it?
@thorman1742 yes built by Ralph Watson I believe. The engine had never been opened up in 30.000 miles which for a race car is very impressive and the reason it was opened up was due to a failed spark plug. Think it's tip broke off but the valves were still absolutely fine.
Rotary valves should be a lot smaller, and sitting in a machined bronze case so it can seal and be lubricated naturally. Adding a small oiling jacket on the shaft can be done to add a very small amount during running. I would imagine oiling it too much will just result in burnt oil in the combustion chamber.
Winded why the use of spherical valves rather than drum type I applaud the use of carbon ceramic surely they could run the carbon ceramic housing and seal in contact with the valve wirhout probs this would surely create a good seal especially spring loaded still be a lot less drag and power sap in the valve train 👍🍻
Just looking at the mechanisms it should be cheaper and less complicated to manufacture but the seals between the valves and the combustion chamber is probably the issue, thus you can’t maintain the seal for a long time of operation
i came up with a piston valve that solved most of the issues, except one... lubrication. and its the same issue that hounds twostrokes... having piston rings pass by ports, piston rings in a cylinder alone, need lubrication.
as an added advantage, as it then creates a form of "opposed piston", it actually increases power delivered to the crankshaft....
yet, as i find it hard to rip people off, or push my concepts that hard to gain development funds, thats where it stays, as a concept. easier to not develop an idea at all than deal with it not quite living up to its claims...
15:1 and higher, thats could be interesting, because we already use 14:1 compression ratio, when we tune an ordinary alcohol powered engine (It came with around 12.5:1 from factory because It is bifuel, need to run with Gasoline too) specially 80's and 90's alcohol engines
The Deane spherical Rotary-Valve long, long proceeded it!
This technology dates back to 1993. It is fantastic but it is sidelined because of emissions constraints.
What will the mpg be?
I have thought about something along these lines before. The obstacles are not so much efficiency or breathing, but chamber sealing for combustion and price of production. And then come carbon concerns: there is a constant burnishing of rotating parts exposed to combustion byproducts. Complex machining gets expensive - try working on a hagglund [hydraulic] motor and you get the picture. I'd like to see this engine concept work , but.. price point vs function? Mass produced engines stick with traditional valves. If this tech was better... F1 would have had a go of it already.
Where could this be useful? Maybe to regulate a high boost system to get away from higher valve spring pressures and free up some power... but that's extra weight. Clocking boost pressure off without changing blower speed when intake valve closes is what I picture. Maybe this finds a marine application.
It always boils down to expense and longevity. The people don't want something that cost a lot and then have to repair every 6 months
Look up,1931 Ralph Watsons bsa rotary valve engine This technology has been around for 90+ years
Problems:
1. thermal expansion
The cylinder head and rotary valves made of different materials and heat up differently so the clearances are constantly changing. In classical engine there are valve springs thah kep valves close and tight no matter the conditions.
2. impossible to keep perfect seal
In classical engine the more pressure inside cylinder the greater force sealing valve. In here thats not the case. Any imperfecion of machining or a little play on camshaft bearings will cause leakage. These spheres dont seem to have thick rigid walls so they can also flex a little bit under combustion pressure
3. additional lubrication required
It looks like there is a great force pushing these spheres up during combustion and compression stroke. Great force and rotating movion required some lubrication and some of this oil will move into cylinder and will be burned. What about emissions?
4. susceptible to contaminants
We have lublicated spherical valves, very tight tolerances, poor emissions and EGR valve. Any contaminant particles will stick into spherical valves and act like a sandpaper.
Conclussion:
It will work on paper or in CAD software but not in real life.
I wil gladly see inside of that kind of engine after a couple thousant of hours working in different conditions.
@ 0.31 sec in. The South African accent takes me a good few years.
Thank you for the information, do you know of fuel efficiency and emissions. Years ago always thought of rotary valves would be better. Have you heard about the Achates motor, also look up Achates Ford f150 and the Achates truck motor. Don't know where it is on the development stage. Again thanks for your information, gives me information on what is happening in the world
Apparently it used 40% less fuel 40% more torque and ran cooler while keeping the oil much cleaner for far longer
I had a 1969 Chevrolet 350 back 1976 that I put a one rotary valve with intake and exhaust same tub to reduce the temperature. Instead of 2.02 intakes and 1.65 exhaust, they were 3.50 intakes and 3.50 exhaust. Could not get the rotary valve to seal!
My question is can you still supercharge or turbocharge the engine with the valves?
This will work great until carbon builds up on the exhaust valves, then things start to break, maybe a 10k mile disassembly schedule for the cylinder heads?
No valve springs, no valve springs float at high rpm. Also, the timing can be fixed on the fly with variable timing added.
Then there is the ease of use and durability seems to be a non issue.
Down sides?
The big cat manufacturers didn't want it because of its own investment in poppet valves and intake etc. It was proposed to Ford and more.
no, with rotary valve designs there is a big catch. Sealing of valve. So every ime vale "closes" some gases bypass valve and go in engine head. This is why rotary valve designs were abandoned.
Some rotary designs had to have 2000rpm iddle in order to run properly.
@@bajkerjohnvolta there is a solution with 100% sealed ones, looked at that video a while ago.
That's the engine top proposed to Ford etc.
@@smaberg hmm oki. Interesting. Ill take a look. Thx.