For moving the ball up and down to change the ratio automatically, you can look into "flyball governors" as used in steam engines. They use centrifugal force to fling weights outwards, which in turn pulls on a linkage which controls the engine throttle (or the ball in your case). If set up correctly, this forms a feedback loop. Windmill speeds up, weights fling out, ball is moved to keep the ratio constant. Interesting concept, keep up the good work Robert!
I thought the same thing. I saw them in use on hydro-electric generators to maintain speed with differing water pressures. Instead of a throttle, they changed to angle of the inlet gates (or something similar. It was a while back).
@@joejansen7029 In hydro electric its wasn't for the changing water pressure but for the changing electrical load on the turbine that might cause the generator to speed up or slow down. Well spotted though :)
@@joejansen7029 that is correct, in high head turbines the governor operates a “spear valve” to adjust the flow of water so that the output from the generator stays close to its rating, or a level chosen by the operator.
In 1958 my first industrial history lesson at age of 12 years was a variable twin cone and belt transmission as used in early Victorian windmills in Britain. The point was that the mill stones would have a constant speed thus reducing the high liability of fire in the flour laden atmosphere which was explosive under certain conditions. Shortly afterwards Daffodil in the sixties marketed the Daffodil variomatic transmission. When I commented on this to my toolmaking uncle he showed me his Robin Hood lathe which worked by a similar transmission and was designed in WWII as a raining machine for workshop machinists. I still use this machine today for hobby processes! As the Presenter suggests there is merely the upgrading of old ideas!
Nice video! Some wind turbines achieve speed matching through variable pitch blade hubs, but usually these days a variable frequency converter is used between the generator and the (fixed speed) grid, so that the mechanical complexity up in the nacelle is minimised!
I was having lunch in the USA today while my Subaru CVT was serviced, and thought what a wonderful solution CVT drive would be for wind generation. I was thinking of a spinning cone drive as a simple solution. Then just now, Robert, your CVT video was in my and today's RUclips notifications. Our minds must be linked up all the way across the pond. : )
Good job mate, came to the same conclusion several years ago after realizing just how good the variable transmission on my motor bike actually is and how well matched it would be for wind generation, I can vouch after doing 150,000 km that I've never had a problem, never had to adjust anything, the only change I made was putting lighter rollers in for faster start speeds and higher torque ratio's up hills.
I also have considered the problem of wind turbine CVT and came up with my own idea using a variant of the disc system. Using a keyed shaft attached directly to the turbine, a classic spinning ball governor to pull an omni or mecanum wheel up and down the keyed shaft and take the output from the spinning disc, thus providing a purely mechanical control system. Admittedly the output speed would probably not be completely constant, but I have always lived by the KISS principal.
This was such a well presented history and explanation of transmissions! Your videos are always great and very enjoyable but this one just seemed even more so! *Thank* you Robert! PS - I hope we'll get some nice historical/technical travel videos (near or far) this summer. Cheers!
My friend had a Yamaha scooter with a CV transmission. It was very fun to accelerate. It always had the right amount of power and went up to 70 mph I think. Kind of like an electric car nowadays.
Thank you for the clarification. DAF is a Dutch automobile company that has a rich history in the automotive industry. One of the earliest and most well-known economy cars produced by DAF was the DAF 600, which was introduced in the late 1950s. The DAF 600 was a compact car designed for efficient urban transportation and was one of the first cars to feature a continuously variable transmission (CVT), which was a significant innovation at the time. The CVT allowed for smooth and efficient power delivery, contributing to the car's reputation as an economical and practical choice for drivers. DAF's focus on fuel efficiency and practicality made their cars popular in the European market, especially for urban commuters and those seeking affordable transportation. In addition to the DAF 600, the company produced other notable models, such as the DAF Daffodil and the later DAF 33 and DAF 44, all of which were designed with economy and practicality in mind. DAF also gained recognition for its innovative Variomatic transmission, which contributed to the company's reputation for producing efficient and reliable vehicles. While DAF's focus shifted more towards commercial vehicles in later years, the company's early contributions to the development of economy cars left a lasting impact on the automotive industry.
There's one more CVT that I've seen, and I actually bought one and am putting it onto my tadpole (reverse trike, I'm disabled) that I've upgraded for pedal assist. When I added pedal assist, my whole drivetrain started dying, quickly, so I'm upgrading to belt transmission (Gates and Veer make belt systems for velos) mated to a CVT IGH made by a company called Enviolo. There's a bike company called Priority that offers CVT as a factory option on their bikes. I'm not affiliated with any of these companies, I feel like I have to keep saying that. I spent 25 years in many areas of technology development and deployment and while I can't have that job any more (they fired me, they only have to wait 12 weeks by law to replace an injured person) I have pretty much everything I learned still knocking about somewhere in my cells. I don't want to see that wasted - so I drop these things in places...to see if someone finds the thing I did, and encounters the same joy. Even if our projects are different, our joy is still the same. Joy is joy. Everyone should have some more.
Easy enough to move the Golf Ball - place it on a rail where its position is determined by centrifugal weights attached to a small flywheel attached to the main input of the Wind Turbine shaft. As the Wind Turbine Shaft's speed increases/decreases - the weights will move and this movement is applied to the Golf Balls Horizontal position. Similar to the method of 'tuning' an old fashioned Car Distributor.
Good idea , but there is no feedback. The graal is to find a way to drive the ball by the output speed error. Not so easy if we want a purely mechanical system. if we mount the ball on an endless screw, we may drive this screw by a disk rolling friction roller. Output centrifugal weight will move the roller on the disk, with the roller at the center for the exact speed.
Was thinking it could use fluid pressure like a modulator valve on an older automatic transmission. The increased rpm would drive a pump to move the ball on a fluid filled rail and to have a spring attached that when rpm decreased it would return to its original position or if rpm is constant fluid pressure would be constant. The only thing is having the fluid pressure over come the spring pressure. Idk just thinking out loud lol. Lots of cool ideas hear
@@jeremybrown8263 Haha! Yeah..I think that would work. The reason I laugh, is because I clicked on this video because of the picture. The cone transmission that I, "invented" several years ago. And then, while reading these comments about regulators, I was thinking about using fluid pressure as a regulator. Actually, only moments before reading down to YOUR comment, which describes the very idea I was thinking on. Haha! Wonderful to be in such good company.
@@melvin6840 cool, I think my idea would work bit in a caveman since of it the guy with the original comment had I good idea about the centrifugal weights, I think maybe an electro magnet that would increase and decrease in intensity do to rpm could also work. But I feel like for now as of reliably fluid pressure would work best,we know much more about fluid dynamics than we do about magnetic effects...I assume I really don't know just still thinking out loud lol sorry for the typos
@@jeremybrown8263 I agree with you on that. Fluid pressure is easier to work with, I think. As the pressure increased, it could push (or pull) against a spring, and change the "gear ratio". Also, having a pressure tank would be a simple way to "start it up" without a load. The windmill wouldn't be pushing against anything until the pressure built up.
Traditionally bob weights would be used to vary the golf ball position. The faster they spin the further they tend to force away from the centre, linking this to the golf ball would be the control. You see the same idea on old steam engines as governors.
Great and informative! I have for a very long time wondered if this problem could not be solved by using the wind to create potential energy, say gravitational, and then later using this potential energy and the consistency of gravity to get the desired hertz.
Lovely stuff. Funny how I have been trying to invent different types of variable transmissions over the years, just for fun, now I see every single one of them has really been produced. + a few I didn't think of... I always thought my ideas were somehow not possible at all. It seems like I was wrong.
It's the most annoying thing ever, believing you've created the next best thing the human race needs only to find out... Already done. So many sleepless nights thinking this is the one time I'm going to beat the odds. Urgh!!!
@@jonbutcher9805 Nice to hear I'm not alone. But I've gotten used to it. I guess that's one reason why older people aren't as innovative as young people, you get cynical and give up on trying new things.
Have a Shopsmith woodworking machine. Its power head as a continuously variable transmission that is essentially two variable diameter pulleys with a single belt between them. And crank handle changes the diameter on one pulley, and the other pulley is spring loaded so that when you make the cranked pulley larger, it pushes the nested pulley halves on the other pulley apart, making its diameter smaller, and vice versa. The thing has worked great for 40 years without ever even replacing the belt.
On the subject of variable transmission there is an Internal Geared Hub for bicycles called the NuVinci which gives a constant variable gear range, believe they’ve mention adapting the system for other applications. Motor vehicles have been mentioned & I’d bet they could be adapted for wind turbines.
What you can use as a setup to move the ball up and down according to whatever setpoint, you can use what old pneumatic steam intergrators used to govern at a set speed. It make use of the centrifugal force on a lever that will provide the feedback or relevant force against a changeable anchor point.
I have a Dixon ZTR that uses a drive system with 2 cones belt driven off the motor, best lawn mower I ever had. It's outlasted another name brand ZTR that has two hydraulic transmissions that I also use. I wish you could still buy them with that type of transmission.
2 cones lined like a motor with coils on the outside and the inner cone like a stator with permanent magnets should make an awesome wind turbine, you could vary the rotation power by moving the stator in and out of the coils, this should eliminate over speeding and improve efficiency, basically a long cone shaped generator. The more magnets you can use in the correct configuration should also eliminate vibration. The further the cone is open the less wind power would be required to start the turbine and it's peak performance would be able to be determined on the fly.
I'm assuming the force of the wind on the blades pushing would cause the cone to be forced back further into the permanent magnets, the magnets interacting with the stater, repelling it back when less wind force acts on the blades? Either way a brake still needs to be implemented for safety and sliding bearings. In the end cost and output Vs the old systems would be what people look at when you put this new design against the old
@@MrRedeyedJedi Yeah, the in-out movement could also be controlled electrically. You could perhaps add a cone on each side, like this , and achieve double the generation and braking effect by moving the outer cones towards each other. This way, you might obtain a magnetic bearing effect, reducing friction significantly and minimizing bearing maintenance. The cost should be offset by increased efficiency. I will build a small-scale prototype and see how it performs.
I have not thought the detail of @voidy remarks totally through. However, I cannot believe that a wind shaft would be viable without a thrust bearing. The dynamics are such as cause potential calamity at an early stage whether by fan or helix. CVT systems are about I/p & o/p linkage in this case in cone form. Electrically the suggestion of intensifying or reducing o/p relative to speed and power demanded in real world conditions would need proving. I imagine this would probably be by a fixed cone on o/p and a sliding cone on i/p. The travelling cone would possibly be via a mechanical scroll over a fixed distance according to speed with advance retard by mechanical or hydraulic recuperation. As you say this would depend upon the complexity of engineering design relative to current gear box economics. Engineering costs vary with availability of materials, the ability to work them, operational process of construction and the maintenance requirements one installed. To this must be added the financial desire of the backers who may well be a mindset apart from the developers. So can the new device if marketed outweigh financially the devices on the current marketplace and is there the political will for such a concept to succeed? This latter is important as if anything interrupts the paper trail of carbon footprint trading in which huge sums are made by financiers and politicians it is a dead duck and I make that statement with a considerable life behind me!!
@@Voidy123 you have a good baseline principle to start on paper, run in simulators, but don't over complicate what you originally thought of. Always start simple on original idea and build from there where needed. The issue with magnetic bearing idea, although a great idea on paper, is the magnetization can weaken over time and it only takes a tiny imbalance and itl stick to the side somewhere. You do have a good idea to work with though
A simple spring-loaded paddle which bends in the wind could move your golf ball. Alternatively, it could move based on torque of input through slightly more complex means.
OMG! I actually understood the conical gear when you used the golf ball! I have TERRIBLE spatial cognition/imagination. The feeling of intuitively understanding something like this is really weird for me. It feels really beautiful. It *looks* really beautiful!
Moving the golf ball is a simple matter of having it linked to a traditional mechanical governor. As the input shaft increases, a linkage from the governor to the golf ball can move it back and forth.
The Swiss EGG automobile had a belt drive variable radius cone transmission in 1896. The same engineer also sold the idea to the Swiss Egli car a few years later.
A very cool one is the Toyota E-CVT power-split device, in their Hybrid Synergy system. Using an electric motor to modulate the relative rotational speed / torque between the input and output, in a epicyclic / planetary gear drive. Basically, what's in th Prius, and all their subsequent hybrid engines.Very reliable, very smooth, very efficient, mechanically very simple, no friction wear.
There was a car called the Owen Magnetic, that utilised a magnetic drive system back the 1920's or 1930's. It was essentially a generator that drove an electric motor, that housed within a single unit, so not strictly a Magnetic drive, but close to it. There was no direct mechanical link between the 6 cylinder motor and the wheels. It was an insane design. It was variable speed(had selectable gears via resistors) and had reverse.. the electric motor also acted as the starter and I believe, also allowed engine braking. Details are a little sketchy. Jay Leno has a fully functional Owen Magnetic car in his museum in California. He featured it on his "Jay Lena's Garage" youtube channel quite a while ago.
One of the joys of a CVT in modern autos is people. We are so used to distinctive gear changes that manufacturers have had to ADD them in, by way of programming the on-board computer for such. This leads to early failure of the CVT because it was designed for SMOOTH, not lurching, transitions. People are stupid. I, personally, am glad I am SMART enough... To remember I, too, am a people. Most of the time. 🙄
for the yoke? control, have a threaded control rod attached to a small stepper motor thats controlled off of an arduino tabled for target ratios at a given fan speed, rpm can be gathered from using hall effect sensors
Ive seen these used in wire production machines, to draw the wire through diamond rings in order to reduce it gauge from 2 inch copper coils down to small enough to use in microchips.
Best channel on RUclips for me. I really appreciate the effort that goes into these videos. If you had a studio and post-production and high quality video, this would be a channel to rival many others
If you embed magnets in the rim of the input cone you could make it pass over a coil and it's rotation speed would determine output voltage of that coil. That in turn could determine the position of a stepper motor controlling the golfgear position. Of course, me being me, I'd want to take more advantage of multiple magnets on the input cone, via a serpentine coil, which could effectively be not just the golfgear control voltage but also a lower power generator, that keeps the golfgear out of contact until it's reaches a speed/torque which is high enough to get something useful from the main generator. The end result would be a dual system, where at low wind speeds it'd use just the input generation system, but above a certain windspeed the main bigger output one too.
Whippletree for combining power from multiple horses. Also used in IBM typewriters to vary force for different characters - less for a full stop and comma - more for letter W.
Wind turbines at the moment use variable pitch control. The gearbox is used to increase the speed of the generator. The generator puts out DC which is then inverted to AC to the correct frequency.
There is a transmission for bicycles that uses cones and balls with a swash plate to change the gearing. There is also a substance like corn starch inside that goes hard under load and then liquid when not loaded. It is not CVT but is is worth a look to help with the design.
Quite an exciting video this is. I just have exactly the right application for this and I had no idea it could be done this way I have to control the speed of a rotating plate and I would have made electronic speed adjustment with a PC board but this is without electronics and therefore I can use a ac motor and have far less interference on the master amplifier which controls the cutting head. The same principle applies to its feedscrew which would allow me stepless groove pitch. This being a vinyl LP record cutting lathe BTW. My current one I made uses dc motor and has interference. Thanks for this.
You could use the electric output to control the position of the golf ball, thusd when input rotation increases, and thus the electric output varies, the ball is moved to a different position.
I have a wind turbine idea. Build a railroad track in a large circle. Put a train on the tracks with flat cars and DC generators that spin up when the train moves and send their power into the tracks. Place sails on the cars that turn to catch the wind, like a sail boat on autopilot. If you built them around towns on elevated tracks they wouldn't interfere with traffic. At 5 knots a 100 square foot sail will make about 1491 watts. That's on par with good solar panels at full sun. I've had people tell me it's a dumb idea but no one can tell me why. A small crew could man it and make sure the automatic controls are working. You might need to design the track so the wheels are locked in and it can't blow over. You could make solid sails instead of canvass if you wanted to make it last longer. If each car had a 60 foot tall by 30 foot sail it would make about 25 kilowatts. If the track was 15 miles long it would make about 15 megawatts. You could also control how much of the sail is in the wind so it doesn't go too fast if it gets windy.
Fascinating! My first motor transport was a Norman 'Nippy' moped which was belt drive via a CVT on the engine. Ball bearings flew out in a captive disc forcing the belt in the V gap up higher thus rotating quicker to drive the rear wheel. Dated from 1959/62 era. This whole video of almost 10 minutes was done in virtually one breath 😊 Please take a bit more time to explain things RObert - still most enjoyable to a mechanically minded person.
i found a curb treadmill but when i saw it i thought, well dang this is old and probably not too much good scalvage. it had a pully setup like this though, changing the width of the belt groove for speed control with a little knob up by some handlebars. oh yes, it has been a wonderful find, and has been a part of many contraptions over the years!
Gearing is so much more important than most automobile companies seem to understand. With proper gearing engines could be about 60%-70% smaller (and there for much more efficient too) they would still achieve the same speeds.
So a possible solution would be a threaded shaft driven by an electric motor and two sensors to measure the rotation of both drives. You can then difference the speeds between the two drives and then drive the thread back and forth to position the golf ball where it needs to go. I don't know if this could be achieved mechanically with some sort of differential gear to vary the threaded shaft to keep the output speed the same. Its worth adding an anemometer and brakes to the input drive from the turbine so that in very windy conditions, the turbine can be shut down to prevent the turbine being destroyed in gales and hurricanes.
Not quite on subject, except for the cvt, but one of my favorite all time systems was in the Harley golf carts in the 1960s or so. They used a single cylinder, 2 cycle engine. Once started, the starter becomes a generator, and to back up, a switch simple runs the motor in reverse. And that goes through and expanding pulley cvt. Amazingly simple, and nearly indestructible in the hands of drunken golfers LOL
So much info packed into ten minutes! What about the braked-planetary transmission on the model T? Revolutionary in it's day. There was an hydraulically-braked planetary transmission made by Carver, instead of braking the rotating gearbox with shoes like the Ford it's rotation was made to pump hydraulic oil, the flow being controlled by a valve to vary the speed.
Another fascinating short and you got me a thunkin'.....design a mechanism that utilizes a wing attachment that would be lifted or lowered depending on the wind speed...as the wind increases or decreases, the wing attachment lever would lift or lower and that lateral up/down motion would then govern where the 'golf ball' sat on the cone rollers.....mmm? anyways, good stuff Rob, you are a great inspiration.
I ran across a NASA Tech Brief in the early 1980's which showed almost the same set up as the one at 4:18. The one major difference was it used a two faceted transference wheel (between the drive and driven cones) which acted to give both surfaces that reduced side slippage during the transfer. For example, if the drive and driven cones shared an angle of say 20 degrees, the transference wheel would be peaked at the midway diameter, with 20 degrees reducing sloops down either side. I though it a good idea and being a NASA Tech Brief means it can be copied, improved upon and used by an American Engineering firm that wished to use it, with their being no Patent nor Intellectual Property Rights exerted by NASA / U.S. Government.
I wonder what they are trying to do differently now with the magnetic type you mention from an eddy-current drive that has been around since the 60's at least. I have numerous pieces of industrial equipment that use an eddy-current coupling to provide variable output from a constant input.
Strange coincidence: Yesterday I read the first time in my life details about CVT transmissions and - voila - today there is your video about this theme. 🤔
Always fascinating! You are the new "Amateur Scientist" (remembering the old Scientific American). References and attributes shared. Applause from the Peanut Gallery (a cultural allusion from the other side of the pond).
Unfortunately there are challenges. There always is. The good thing with gears or chains is they are not only efficient, but they don't slip and a small set can take a large torque. Nearly all variable drives rely on friction. And this means pressure to get it and any slippage causes terrible wearing of parts. And while a ball will make changing the ratio easier. It means there's less contact surface and higher pressure on the tiny spot it touches. One solution is to use one central cone as input or output. And multiple external cones geared together with balls between them in a cage to move them. So you have more than 1 ball. This reduces problems of slippage while keeping the advantage of havung a ball. All the while reducing point load pressure on the balls and cones. Ideally you have the variable drive on the highest RPM part of the drive train so it take the lowest torque possible.
I have many "dead" deep-cycle Marine 12V lead-acid batteries. If new, they'd store and output as much as 14.5VDC. Once someone has thrown them out, you now might expect around 11VDC from them after a charge. But if you attach them in series and use them to run a DC motor, the voltage will determine its speed. Six of these batteries might then run the motor at 60V. With the CVT to an alternator, you could then produce a stable 120VAC output assuming that you have a feedback loop to control it.
Brilliant. You're hard to keep up with, Robert. My poor Elegoo suffered a strike and jam under the gantry. What a mess indeed, and parts not so easy to order from elegoo. Now we'll be further behind the project list. LOL
Of course the problem with using CVT's on wind turbines to prevent run-away generator speed problems is, as the wind speed increases the turbine rotates exponentially faster because as you are only taking a constant amount of power out, a higher percentage of the input (wind) power goes into the spinning of the turbine.
That run-away could be prevented by using a centrifugal governor in some way like those used to control RPM in old steam and fuel engines. Maybe a governor could pull up a rod connected to the ball at a certain speed to lift it up and disconnect the input and output shafts.
Hmm. As was mentioned, lawnmower type of 'CVT' would sound like ideal. As wind speed increases the thrust on the blades increases right? So when the speed is too high the production can be stopped by adding a brake in the middle. Also one gets a 90° angle gearing so that the generator can be brought down for easy maintenance. Hope my rambling makes sense....
The first time I remember having seen anything about the CVT kind of transmission was when the technical trade press told about the Dutch DAF car. Some test report mentioned how odd it felt to just press the gas pedal all the way to floor, and the motor sound never changed, but the car speed did. I think that introduction was some time around 1960, maybe a little earlier, maybe later. Later on, I have seen a number of new versions described, although I never had such a device in my hands. Or maybe I must count the band saw at my working place. The band speed was adjustable by some such device. But the times of disassembling an alarm clock were behind me, so I never saw what was inside...
When the wind power plant is connected to the network, the generator will get very stable RPM because it must be in sync with network. If the generator wants to spin faster, its load to network is simply higher which automatically reduces its RPM. If the generator wants to spin slower, the load is reduced so the RPM is again constant. In the exteme when there is no wind, the generator turns into appliance. It is "windmilled" by power network.
I’ve been working this concept for a while and it seems that a flywheel coupled to the cvt, could maximize available torque, which is otherwise lost outside a small band of efficiency.
In order to remove any potential belt "stretching" or slippage issues with their CVT, Subaru pushes the power from the primary to the secondary with a chain belt rather than pulling the belt. The belt is ....wait for it...a pushie rather than a pulley belt.
Oh that was fun.. my god there are some ingenious inventions out there eh ?! 😊 I always thought a printer would have all right bits to make a really nice precise variable transmission.
An eddy current clutch of a more modern design could also be used to get a variable speed output for a wind turbine. At low wind speeds you would want 100% lockup and as the speed increased, you would want the lockup to lower. Or you could set it up so that as the speed increased on the input, more torque would be applied to the alternator. Older design eddy current clutches used slip rings but a modern one could be built where it all is coupled magnetically. The slip rings being replace by a coil and diodes to produce the DC for the clutch coil itself.
Sometimes you think you invented something but it existed already for a long time lol... can't get a sterling engine to work, that is with current material available, but I figure out I could make a passive mechanism for a walking robot, that translate any harsh push into walking using adaptation of the inverted pendulum principles, those cone transmissions you show is one of the idea I had to program the stride base on the input force, but the cone aren't regular, they encode a profile in the varying radius along the height of the cone. Mot sure if I can build the whole thing yet though.
Been trying to figure out the solution to the exact problems you mentioned here mate! And just as I see this video in the list, you bet I click it faster than the speed of light. I was also thinking of a high response voltage regulator to attach to the turbine generator such that the generator output voltage remains the same. Something like a variac or autotransformer or something. Could also be practical? Amazed by the varieties of CVTa you mentioned here, always tried looking for more designs of CVTs.. but couldn't find. You may have shown something that is potentially more reliable, robust, and efficient and practical. Waiting for you to amaze us with more phenomenon or trick or many useful unknowns that are as amazing as you are sir.
FUNTastyX has a video of a lego cvt made with a couple balls and wheels you might find interesting. as for how to control the cvt, maybe a centrifugal governor, so the speed of the windmill determines the ratio of the cvt?
Hydraulic torque converters have torque multiplication via fluid impeller and stator connected to transmission of ratios. Much less parasitic loss than belt cvt
I bought a brand new automatic Dacia Sandero (I know, exciting) which has a CVT (presumably Nissan derived from the Renault partnership?) but unlike the CVT Subaru Justy I drove many many years ago - this one has electronic mapping to make it "feel" like a regular automatic transmission. It's very strange as, despite claiming to be a CVT gearbox, it feels exactly like a (pretty poor) regular automatic. I assume they did this for marketing reasons but I can't imagine it helps the efficiency at all. Its a shame because I am (one of the few, it seems) who really enjoys the unique way a CVT feels in a car and its a gearbox I have always been a huge fan of!
i would use a stepper motor to control the transmission, an alternator for the generator so i can manipulate the magnetic field and use a raspberry pi or simular as management.... just not sure what turbine i would use for it.... would love to see you build something like that. i really enjoy your channel and started experimenting with turbines again thanks to you
I love that ! It reminde's me an other marvelous thing that could maybe somehow connect, the "régulateur d'allure" (in dont know if there is an EN translation sorry) invented by a crazy navigator ...(Moitessier if i remember well..) In the wind turbine case, the "regulating thing" could be some electromagnetic field transmitted from the turbine to adjust the gearing ratio?
Also hitting on a whole range of variable speed transmissions, with patents over 100 years old! I still haven't seen anything on using radiating shafts on an axel, with counterweights, which would be able to change the shaft size with centrifugal force - also something I've been milling over. It's a brilliant idea and would be very useful in wind generators, where you could keep the turbine/blades running at a constant speed, but vary the torque, depending on the wind force... there's a 100 year old patent on that, too, isn't there?
So if you turned it on it's side, would the natural propensity for the golf ball to be attracted downwards by gravity be overcompensated by the speed of the turbine - ie. would it want to raise upwards (to an 'easier' ratio) as the speed of the input increases? (I suspect not but might be an interesting test)
For moving the ball up and down to change the ratio automatically, you can look into "flyball governors" as used in steam engines. They use centrifugal force to fling weights outwards, which in turn pulls on a linkage which controls the engine throttle (or the ball in your case). If set up correctly, this forms a feedback loop. Windmill speeds up, weights fling out, ball is moved to keep the ratio constant. Interesting concept, keep up the good work Robert!
I thought the same thing. I saw them in use on hydro-electric generators to maintain speed with differing water pressures. Instead of a throttle, they changed to angle of the inlet gates (or something similar. It was a while back).
@@joejansen7029 In hydro electric its wasn't for the changing water pressure but for the changing electrical load on the turbine that might cause the generator to speed up or slow down. Well spotted though :)
They used the same system in grist mills,both hydro and wind powered at least as far back as the 1800's.
@@joejansen7029 that is correct, in high head turbines the governor operates a “spear valve” to adjust the flow of water so that the output from the generator stays close to its rating, or a level chosen by the operator.
I think that's where the term "balls to the wall" came from lol
In 1958 my first industrial history lesson at age of 12 years was a variable twin cone and belt transmission as used in early Victorian windmills in Britain. The point was that the mill stones would have a constant speed thus reducing the high liability of fire in the flour laden atmosphere which was explosive under certain conditions. Shortly afterwards Daffodil in the sixties marketed the Daffodil variomatic transmission. When I commented on this to my toolmaking uncle he showed me his Robin Hood lathe which worked by a similar transmission and was designed in WWII as a raining machine for workshop machinists. I still use this machine today for hobby processes! As the Presenter suggests there is merely the upgrading of old ideas!
Nice video! Some wind turbines achieve speed matching through variable pitch blade hubs, but usually these days a variable frequency converter is used between the generator and the (fixed speed) grid, so that the mechanical complexity up in the nacelle is minimised!
I was having lunch in the USA today while my Subaru CVT was serviced, and thought what a wonderful solution CVT drive would be for wind generation. I was thinking of a spinning cone drive as a simple solution. Then just now, Robert, your CVT video was in my and today's RUclips notifications. Our minds must be linked up all the way across the pond. : )
Good job mate, came to the same conclusion several years ago after realizing just how good the variable transmission on my motor bike actually is and how well matched it would be for wind generation, I can vouch after doing 150,000 km that I've never had a problem, never had to adjust anything, the only change I made was putting lighter rollers in for faster start speeds and higher torque ratio's up hills.
What bike do you have?
@@friedrichvonsnatch3501 A small 110 cc scooter, don't sound impressive, but 150,000 km's says otherwise lol
Another enjoyable and educational video as always. Thank you very much for your hard work Mr. Robert Murray-Smith. You are a gentleman and a scholar.
I also have considered the problem of wind turbine CVT and came up with my own idea using a variant of the disc system.
Using a keyed shaft attached directly to the turbine, a classic spinning ball governor to pull an omni or mecanum wheel up and down the keyed shaft and take the output from the spinning disc, thus providing a purely mechanical control system.
Admittedly the output speed would probably not be completely constant, but I have always lived by the KISS principal.
Ever heard of VRT Innovations? The D-Drive?
Bloody Awesome; love new and using old tech.
This was such a well presented history and explanation of transmissions! Your videos are always great and very enjoyable but this one just seemed even more so!
*Thank* you Robert!
PS - I hope we'll get some nice historical/technical travel videos (near or far) this summer. Cheers!
No mention of the D-Drive? VRT Innovations. Sounds a lot more interesting than any of those mentioned!
@@cymacymulacra2301 who manufactures it or what system is it used in?
My friend had a Yamaha scooter with a CV transmission. It was very fun to accelerate. It always had the right amount of power and went up to 70 mph I think. Kind of like an electric car nowadays.
Thank you for the clarification. DAF is a Dutch automobile company that has a rich history in the automotive industry. One of the earliest and most well-known economy cars produced by DAF was the DAF 600, which was introduced in the late 1950s. The DAF 600 was a compact car designed for efficient urban transportation and was one of the first cars to feature a continuously variable transmission (CVT), which was a significant innovation at the time.
The CVT allowed for smooth and efficient power delivery, contributing to the car's reputation as an economical and practical choice for drivers. DAF's focus on fuel efficiency and practicality made their cars popular in the European market, especially for urban commuters and those seeking affordable transportation.
In addition to the DAF 600, the company produced other notable models, such as the DAF Daffodil and the later DAF 33 and DAF 44, all of which were designed with economy and practicality in mind. DAF also gained recognition for its innovative Variomatic transmission, which contributed to the company's reputation for producing efficient and reliable vehicles.
While DAF's focus shifted more towards commercial vehicles in later years, the company's early contributions to the development of economy cars left a lasting impact on the automotive industry.
The most efficient, durable, and elegant designs have a healthy dose of simplicity. Ruthlessly hack away the unimportant.
You have no idea how frustrating it was trying to find any information on this through a browser.
Thank you so much for uploading this video.
There's one more CVT that I've seen, and I actually bought one and am putting it onto my tadpole (reverse trike, I'm disabled) that I've upgraded for pedal assist. When I added pedal assist, my whole drivetrain started dying, quickly, so I'm upgrading to belt transmission (Gates and Veer make belt systems for velos) mated to a CVT IGH made by a company called Enviolo. There's a bike company called Priority that offers CVT as a factory option on their bikes. I'm not affiliated with any of these companies, I feel like I have to keep saying that.
I spent 25 years in many areas of technology development and deployment and while I can't have that job any more (they fired me, they only have to wait 12 weeks by law to replace an injured person) I have pretty much everything I learned still knocking about somewhere in my cells. I don't want to see that wasted - so I drop these things in places...to see if someone finds the thing I did, and encounters the same joy. Even if our projects are different, our joy is still the same. Joy is joy. Everyone should have some more.
Easy enough to move the Golf Ball - place it on a rail where its position is determined by centrifugal weights attached to a small flywheel attached to the main input of the Wind Turbine shaft. As the Wind Turbine Shaft's speed increases/decreases - the weights will move and this movement is applied to the Golf Balls Horizontal position. Similar to the method of 'tuning' an old fashioned Car Distributor.
Good idea , but there is no feedback. The graal is to find a way to drive the ball by the output speed error. Not so easy if we want a purely mechanical system. if we mount the ball on an endless screw, we may drive this screw by a disk rolling friction roller. Output centrifugal weight will move the roller on the disk, with the roller at the center for the exact speed.
Was thinking it could use fluid pressure like a modulator valve on an older automatic transmission. The increased rpm would drive a pump to move the ball on a fluid filled rail and to have a spring attached that when rpm decreased it would return to its original position or if rpm is constant fluid pressure would be constant. The only thing is having the fluid pressure over come the spring pressure. Idk just thinking out loud lol. Lots of cool ideas hear
@@jeremybrown8263
Haha! Yeah..I think that would work.
The reason I laugh, is because I clicked on this video because of the picture. The cone transmission that I, "invented" several years ago.
And then, while reading these comments about regulators, I was thinking about using fluid pressure as a regulator. Actually, only moments before reading down to YOUR comment, which describes the very idea I was thinking on.
Haha!
Wonderful to be in such good company.
@@melvin6840 cool, I think my idea would work bit in a caveman since of it the guy with the original comment had I good idea about the centrifugal weights, I think maybe an electro magnet that would increase and decrease in intensity do to rpm could also work. But I feel like for now as of reliably fluid pressure would work best,we know much more about fluid dynamics than we do about magnetic effects...I assume I really don't know just still thinking out loud lol sorry for the typos
@@jeremybrown8263
I agree with you on that. Fluid pressure is easier to work with, I think. As the pressure increased, it could push (or pull) against a spring, and change the "gear ratio". Also, having a pressure tank would be a simple way to "start it up" without a load. The windmill wouldn't be pushing against anything until the pressure built up.
Traditionally bob weights would be used to vary the golf ball position. The faster they spin the further they tend to force away from the centre, linking this to the golf ball would be the control. You see the same idea on old steam engines as governors.
That's where the term "balls to the wall" meaning "full speed" comes from.
Great and informative! I have for a very long time wondered if this problem could not be solved by using the wind to create potential energy, say gravitational, and then later using this potential energy and the consistency of gravity to get the desired hertz.
Lovely stuff. Funny how I have been trying to invent different types of variable transmissions over the years, just for fun, now I see every single one of them has really been produced. + a few I didn't think of... I always thought my ideas were somehow not possible at all. It seems like I was wrong.
It's the most annoying thing ever, believing you've created the next best thing the human race needs only to find out... Already done.
So many sleepless nights thinking this is the one time I'm going to beat the odds. Urgh!!!
@@jonbutcher9805 Nice to hear I'm not alone. But I've gotten used to it. I guess that's one reason why older people aren't as innovative as young people, you get cynical and give up on trying new things.
@@TheRealFOSFOR amen brother. Dreams are for the young.
Have a Shopsmith woodworking machine. Its power head as a continuously variable transmission that is essentially two variable diameter pulleys with a single belt between them. And crank handle changes the diameter on one pulley, and the other pulley is spring loaded so that when you make the cranked pulley larger, it pushes the nested pulley halves on the other pulley apart, making its diameter smaller, and vice versa. The thing has worked great for 40 years without ever even replacing the belt.
On the subject of variable transmission there is an Internal Geared Hub for bicycles called the NuVinci which gives a constant variable gear range, believe they’ve mention adapting the system for other applications. Motor vehicles have been mentioned & I’d bet they could be adapted for wind turbines.
what gear ratios do they support? is it more of a city bike or for more terrains? what are its advantages?
What you can use as a setup to move the ball up and down according to whatever setpoint, you can use what old pneumatic steam intergrators used to govern at a set speed. It make use of the centrifugal force on a lever that will provide the feedback or relevant force against a changeable anchor point.
I have a Dixon ZTR that uses a drive system with 2 cones belt driven off the motor, best lawn mower I ever had. It's outlasted another name brand ZTR that has two hydraulic transmissions that I also use. I wish you could still buy them with that type of transmission.
Well, rubber is a consumable. Probably best to go with anything but rubber. Very informative presentation, loved it.
great to see an idea put into reality, Robert - wtg! Looking forward to see it working effeciently.
2 cones lined like a motor with coils on the outside and the inner cone like a stator with permanent magnets should make an awesome wind turbine, you could vary the rotation power by moving the stator in and out of the coils, this should eliminate over speeding and improve efficiency, basically a long cone shaped generator. The more magnets you can use in the correct configuration should also eliminate vibration. The further the cone is open the less wind power would be required to start the turbine and it's peak performance would be able to be determined on the fly.
Sounds good what’s stopping you!
I'm assuming the force of the wind on the blades pushing would cause the cone to be forced back further into the permanent magnets, the magnets interacting with the stater, repelling it back when less wind force acts on the blades? Either way a brake still needs to be implemented for safety and sliding bearings. In the end cost and output Vs the old systems would be what people look at when you put this new design against the old
@@MrRedeyedJedi Yeah, the in-out movement could also be controlled electrically. You could perhaps add a cone on each side, like this , and achieve double the generation and braking effect by moving the outer cones towards each other. This way, you might obtain a magnetic bearing effect, reducing friction significantly and minimizing bearing maintenance. The cost should be offset by increased efficiency. I will build a small-scale prototype and see how it performs.
I have not thought the detail of @voidy remarks totally through. However, I cannot believe that a wind shaft would be viable without a thrust bearing. The dynamics are such as cause potential calamity at an early stage whether by fan or helix. CVT systems are about I/p & o/p linkage in this case in cone form. Electrically the suggestion of intensifying or reducing o/p relative to speed and power demanded in real world conditions would need proving.
I imagine this would probably be by a fixed cone on o/p and a sliding cone on i/p. The travelling cone would possibly be via a mechanical scroll over a fixed distance according to speed with advance retard by mechanical or hydraulic recuperation. As you say this would depend upon the complexity of engineering design relative to current gear box economics.
Engineering costs vary with availability of materials, the ability to work them, operational process of construction and the maintenance requirements one installed. To this must be added the financial desire of the backers who may well be a mindset apart from the developers. So can the new device if marketed outweigh financially the devices on the current marketplace and is there the political will for such a concept to succeed? This latter is important as if anything interrupts the paper trail of carbon footprint trading in which huge sums are made by financiers and politicians it is a dead duck and I make that statement with a considerable life behind me!!
@@Voidy123 you have a good baseline principle to start on paper, run in simulators, but don't over complicate what you originally thought of. Always start simple on original idea and build from there where needed. The issue with magnetic bearing idea, although a great idea on paper, is the magnetization can weaken over time and it only takes a tiny imbalance and itl stick to the side somewhere. You do have a good idea to work with though
A simple spring-loaded paddle which bends in the wind could move your golf ball.
Alternatively, it could move based on torque of input through slightly more complex means.
I love simplicity and think your spring load idea is brilliant.
The constantinesco torque converter is one of my favourite IVT out there! Loved the mention! Not often you hear it on here!
OMG! I actually understood the conical gear when you used the golf ball! I have TERRIBLE spatial cognition/imagination. The feeling of intuitively understanding something like this is really weird for me. It feels really beautiful. It *looks* really beautiful!
RMS, a mouse ball out of an old mouse would work great. It's hard and rubber coated. Fascinating! Thanks for sharing! Cheers!
Moving the golf ball is a simple matter of having it linked to a traditional mechanical governor. As the input shaft increases, a linkage from the governor to the golf ball can move it back and forth.
The Swiss EGG automobile had a belt drive variable radius cone transmission in 1896. The same engineer also sold the idea to the Swiss Egli car a few years later.
A very cool one is the Toyota E-CVT power-split device, in their Hybrid Synergy system. Using an electric motor to modulate the relative rotational speed / torque between the input and output, in a epicyclic / planetary gear drive. Basically, what's in th Prius, and all their subsequent hybrid engines.Very reliable, very smooth, very efficient, mechanically very simple, no friction wear.
There was a car called the Owen Magnetic, that utilised a magnetic drive system back the 1920's or 1930's. It was essentially a generator that drove an electric motor, that housed within a single unit, so not strictly a Magnetic drive, but close to it. There was no direct mechanical link between the 6 cylinder motor and the wheels. It was an insane design.
It was variable speed(had selectable gears via resistors) and had reverse.. the electric motor also acted as the starter and I believe, also allowed engine braking. Details are a little sketchy.
Jay Leno has a fully functional Owen Magnetic car in his museum in California. He featured it on his "Jay Lena's Garage" youtube channel quite a while ago.
One of the joys of a CVT in modern autos is people.
We are so used to distinctive gear changes that manufacturers have had to ADD them in, by way of programming the on-board computer for such.
This leads to early failure of the CVT because it was designed for SMOOTH, not lurching, transitions.
People are stupid. I, personally, am glad I am SMART enough...
To remember I, too, am a people. Most of the time. 🙄
I had been wondering about CVTs on wind turbines since about 2021. Am glad to finally see it covered. Look forward to seeing what you do with it :D
for the yoke? control, have a threaded control rod attached to a small stepper motor thats controlled off of an arduino tabled for target ratios at a given fan speed, rpm can be gathered from using hall effect sensors
Ive seen these used in wire production machines, to draw the wire through diamond rings in order to reduce it gauge from 2 inch copper coils down to small enough to use in microchips.
I watch your videos all the time and have learned so much from you. Thank you and please keep making the great videos.
Best channel on RUclips for me. I really appreciate the effort that goes into these videos. If you had a studio and post-production and high quality video, this would be a channel to rival many others
Wow, thank you!
If you embed magnets in the rim of the input cone you could make it pass over a coil and it's rotation speed would determine output voltage of that coil. That in turn could determine the position of a stepper motor controlling the golfgear position.
Of course, me being me, I'd want to take more advantage of multiple magnets on the input cone, via a serpentine coil, which could effectively be not just the golfgear control voltage but also a lower power generator, that keeps the golfgear out of contact until it's reaches a speed/torque which is high enough to get something useful from the main generator. The end result would be a dual system, where at low wind speeds it'd use just the input generation system, but above a certain windspeed the main bigger output one too.
My projects are over flowing out my garage from watching your channel
lol - oops my bad! lol
Whippletree for combining power from multiple horses. Also used in IBM typewriters to vary force for different characters - less for a full stop and comma - more for letter W.
That, I never knew but makes sense. Remember old mechanical typewriters where the full stop would practically go through the paper.
The Whippet used a manually controlled CVT similar to the Snapper mower transmission.
Wind turbines at the moment use variable pitch control. The gearbox is used to increase the speed of the generator.
The generator puts out DC which is then inverted to AC to the correct frequency.
There is a transmission for bicycles that uses cones and balls with a swash plate to change the gearing. There is also a substance like corn starch inside that goes hard under load and then liquid when not loaded. It is not CVT but is is worth a look to help with the design.
Quite an exciting video this is. I just have exactly the right application for this and I had no idea it could be done this way I have to control the speed of a rotating plate and I would have made electronic speed adjustment with a PC board but this is without electronics and therefore I can use a ac motor and have far less interference on the master amplifier which controls the cutting head. The same principle applies to its feedscrew which would allow me stepless groove pitch. This being a vinyl LP record cutting lathe BTW. My current one I made uses dc motor and has interference. Thanks for this.
I kept waiting for you to demo how the Toyota hybrids work as the all use CVT and it’s brilliant to power the wheels or recover energy!
You could use the electric output to control the position of the golf ball, thusd when input rotation increases, and thus the electric output varies, the ball is moved to a different position.
I have a wind turbine idea. Build a railroad track in a large circle. Put a train on the tracks with flat cars and DC generators that spin up when the train moves and send their power into the tracks. Place sails on the cars that turn to catch the wind, like a sail boat on autopilot. If you built them around towns on elevated tracks they wouldn't interfere with traffic. At 5 knots a 100 square foot sail will make about 1491 watts. That's on par with good solar panels at full sun. I've had people tell me it's a dumb idea but no one can tell me why. A small crew could man it and make sure the automatic controls are working. You might need to design the track so the wheels are locked in and it can't blow over. You could make solid sails instead of canvass if you wanted to make it last longer. If each car had a 60 foot tall by 30 foot sail it would make about 25 kilowatts. If the track was 15 miles long it would make about 15 megawatts. You could also control how much of the sail is in the wind so it doesn't go too fast if it gets windy.
Outstanding presentation, very entertaining. Thanks.
DAF used it, and now most cars use CVT transmissions.
Cotton mills also used cone drives CVTs to.
Disadvantage is Limited in power transfer.
Fascinating! My first motor transport was a Norman 'Nippy' moped which was belt drive via a CVT on the engine. Ball bearings flew out in a captive disc forcing the belt in the V gap up higher thus rotating quicker to drive the rear wheel. Dated from 1959/62 era. This whole video of almost 10 minutes was done in virtually one breath 😊 Please take a bit more time to explain things RObert - still most enjoyable to a mechanically minded person.
Gosh I cant wait for the next installment, thrilling stuff. Your videos should be part of the national curriculum.
i found a curb treadmill but when i saw it i thought, well dang this is old and probably not too much good scalvage. it had a pully setup like this though, changing the width of the belt groove for speed control with a little knob up by some handlebars. oh yes, it has been a wonderful find, and has been a part of many contraptions over the years!
Gearing is so much more important than most automobile companies seem to understand.
With proper gearing engines could be about 60%-70% smaller (and there for much more efficient too) they would still achieve the same speeds.
A centrifugal governor attached to the output shaft of the turbine seems the most logical choice.
Moving that golf ball sounds like a job for a centrifugal governor to me. Sort of thing James Watt would approve of 😂
I love mechanical transmissions.
When I was a kid, I had many nocturnal transmissions. 🤔🤣
So a possible solution would be a threaded shaft driven by an electric motor and two sensors to measure the rotation of both drives. You can then difference the speeds between the two drives and then drive the thread back and forth to position the golf ball where it needs to go. I don't know if this could be achieved mechanically with some sort of differential gear to vary the threaded shaft to keep the output speed the same. Its worth adding an anemometer and brakes to the input drive from the turbine so that in very windy conditions, the turbine can be shut down to prevent the turbine being destroyed in gales and hurricanes.
Not quite on subject, except for the cvt, but one of my favorite all time systems was in the Harley golf carts in the 1960s or so.
They used a single cylinder, 2 cycle engine. Once started, the starter becomes a generator, and to back up, a switch simple runs the motor in reverse. And that goes through and expanding pulley cvt. Amazingly simple, and nearly indestructible in the hands of drunken golfers LOL
So much info packed into ten minutes! What about the braked-planetary transmission on the model T? Revolutionary in it's day. There was an hydraulically-braked planetary transmission made by Carver, instead of braking the rotating gearbox with shoes like the Ford it's rotation was made to pump hydraulic oil, the flow being controlled by a valve to vary the speed.
Another fascinating short and you got me a thunkin'.....design a mechanism that utilizes a wing attachment that would be lifted or lowered depending on the wind speed...as the wind increases or decreases, the wing attachment lever would lift or lower and that lateral up/down motion would then govern where the 'golf ball' sat on the cone rollers.....mmm? anyways, good stuff Rob, you are a great inspiration.
I ran across a NASA Tech Brief in the early 1980's which showed almost the same set up as the one at 4:18. The one major difference was it used a two faceted transference wheel (between the drive and driven cones) which acted to give both surfaces that reduced side slippage during the transfer.
For example, if the drive and driven cones shared an angle of say 20 degrees, the transference wheel would be peaked at the midway diameter, with 20 degrees reducing sloops down either side.
I though it a good idea and being a NASA Tech Brief means it can be copied, improved upon and used by an American Engineering firm that wished to use it, with their being no Patent nor Intellectual Property Rights exerted by NASA / U.S. Government.
I wonder what they are trying to do differently now with the magnetic type you mention from an eddy-current drive that has been around since the 60's at least. I have numerous pieces of industrial equipment that use an eddy-current coupling to provide variable output from a constant input.
Mate, I love your enthusiasm for making. Keep on it! Cheers
Strange coincidence: Yesterday I read the first time in my life details about CVT transmissions and - voila - today there is your video about this theme. 🤔
Always fascinating! You are the new "Amateur Scientist" (remembering the old Scientific American). References and attributes shared. Applause from the Peanut Gallery (a cultural allusion from the other side of the pond).
I live on a golf corse and find 'em lay in 'round my yard. FINALLY found a way to utilize those "pesky" things!!!
Unfortunately there are challenges. There always is.
The good thing with gears or chains is they are not only efficient, but they don't slip and a small set can take a large torque.
Nearly all variable drives rely on friction. And this means pressure to get it and any slippage causes terrible wearing of parts.
And while a ball will make changing the ratio easier. It means there's less contact surface and higher pressure on the tiny spot it touches.
One solution is to use one central cone as input or output. And multiple external cones geared together with balls between them in a cage to move them. So you have more than 1 ball. This reduces problems of slippage while keeping the advantage of havung a ball. All the while reducing point load pressure on the balls and cones.
Ideally you have the variable drive on the highest RPM part of the drive train so it take the lowest torque possible.
I have many "dead" deep-cycle Marine 12V lead-acid batteries. If new, they'd store and output as much as 14.5VDC. Once someone has thrown them out, you now might expect around 11VDC from them after a charge. But if you attach them in series and use them to run a DC motor, the voltage will determine its speed. Six of these batteries might then run the motor at 60V. With the CVT to an alternator, you could then produce a stable 120VAC output assuming that you have a feedback loop to control it.
Brilliant. You're hard to keep up with, Robert. My poor Elegoo suffered a strike and jam under the gantry. What a mess indeed, and parts not so easy to order from elegoo. Now we'll be further behind the project list. LOL
Oh no!
@@ThinkingandTinkering My Z offset went from -0.720 to +3.240. It's a mess.
Of course the problem with using CVT's on wind turbines to prevent run-away generator speed problems is, as the wind speed increases the turbine rotates exponentially faster because as you are only taking a constant amount of power out, a higher percentage of the input (wind) power goes into the spinning of the turbine.
That run-away could be prevented by using a centrifugal governor in some way like those used to control RPM in old steam and fuel engines.
Maybe a governor could pull up a rod connected to the ball at a certain speed to lift it up and disconnect the input and output shafts.
@@DeeDee-pw9pm See my other comment
Hmm.
As was mentioned, lawnmower type of 'CVT' would sound like ideal. As wind speed increases the thrust on the blades increases right?
So when the speed is too high the production can be stopped by adding a brake in the middle. Also one gets a 90° angle gearing so that the generator can be brought down for easy maintenance.
Hope my rambling makes sense....
Always enjoyable and informative!
The first time I remember having seen anything about the CVT kind of transmission was when the technical trade press told about the Dutch DAF car. Some test report mentioned how odd it felt to just press the gas pedal all the way to floor, and the motor sound never changed, but the car speed did. I think that introduction was some time around 1960, maybe a little earlier, maybe later. Later on, I have seen a number of new versions described, although I never had such a device in my hands. Or maybe I must count the band saw at my working place. The band speed was adjustable by some such device. But the times of disassembling an alarm clock were behind me, so I never saw what was inside...
I think you have seen the introduction of the Daf 600 which was produced from 1958 to 1963.
When the wind power plant is connected to the network, the generator will get very stable RPM because it must be in sync with network. If the generator wants to spin faster, its load to network is simply higher which automatically reduces its RPM. If the generator wants to spin slower, the load is reduced so the RPM is again constant. In the exteme when there is no wind, the generator turns into appliance. It is "windmilled" by power network.
A speed governor on the input side that pulls or pushes on the drive ajuster is all that is needed.
I’ve been working this concept for a while and it seems that a flywheel coupled to the cvt, could maximize available torque, which is otherwise lost outside a small band of efficiency.
Your videos are always excellent. Helped me a lot .Thanks :)
The Constantinesco type transmission was always an interesting option.
Torque interface is the killer. No one has sorted that one out yet. The contact face relies on friction, and therein lays the rub.... literally.
In order to remove any potential belt "stretching" or slippage issues with their CVT, Subaru pushes the power from the primary to the secondary with a chain belt rather than pulling the belt. The belt is ....wait for it...a pushie rather than a pulley belt.
Only just stumbled upon this channel, brilliant content!!!
Cheers, mate!
The demand should place the ball in the position best suited to provide power for the task. Pure physics.
I remember this from DAF cars. Great idea.
@@rocklover7437 i had one of those for years, ran like a dream, the revers was as fast as forward .. lol
@@rocklover7437 yes they did and used the daf system for short period , my brother in law had one 👍
@@gj7685 the reason they put it in the 340 series was that they had a huge amount of surplus in stock after the merging with DAF
@@MRunar007 you'd think with modern tech some could revive the idea but then again we'll be going all electric although there's still hydrogen cars 😄
Oh that was fun.. my god there are some ingenious inventions out there eh ?! 😊 I always thought a printer would have all right bits to make a really nice precise variable transmission.
An eddy current clutch of a more modern design could also be used to get a variable speed output for a wind turbine. At low wind speeds you would want 100% lockup and as the speed increased, you would want the lockup to lower. Or you could set it up so that as the speed increased on the input, more torque would be applied to the alternator. Older design eddy current clutches used slip rings but a modern one could be built where it all is coupled magnetically. The slip rings being replace by a coil and diodes to produce the DC for the clutch coil itself.
Sometimes you think you invented something but it existed already for a long time lol... can't get a sterling engine to work, that is with current material available, but I figure out I could make a passive mechanism for a walking robot, that translate any harsh push into walking using adaptation of the inverted pendulum principles, those cone transmissions you show is one of the idea I had to program the stride base on the input force, but the cone aren't regular, they encode a profile in the varying radius along the height of the cone. Mot sure if I can build the whole thing yet though.
Been trying to figure out the solution to the exact problems you mentioned here mate!
And just as I see this video in the list, you bet I click it faster than the speed of light.
I was also thinking of a high response voltage regulator to attach to the turbine generator such that the generator output voltage remains the same.
Something like a variac or autotransformer or something. Could also be practical?
Amazed by the varieties of CVTa you mentioned here, always tried looking for more designs of CVTs.. but couldn't find. You may have shown something that is potentially more reliable, robust, and efficient and practical.
Waiting for you to amaze us with more phenomenon or trick or many useful unknowns that are as amazing as you are sir.
Okay......I think I might be hooked . I will watch more of your videos.
FUNTastyX has a video of a lego cvt made with a couple balls and wheels you might find interesting.
as for how to control the cvt, maybe a centrifugal governor, so the speed of the windmill determines the ratio of the cvt?
Hydraulic torque converters have torque multiplication via fluid impeller and stator connected to transmission of ratios.
Much less parasitic loss than belt cvt
I bought a brand new automatic Dacia Sandero (I know, exciting) which has a CVT (presumably Nissan derived from the Renault partnership?) but unlike the CVT Subaru Justy I drove many many years ago - this one has electronic mapping to make it "feel" like a regular automatic transmission. It's very strange as, despite claiming to be a CVT gearbox, it feels exactly like a (pretty poor) regular automatic. I assume they did this for marketing reasons but I can't imagine it helps the efficiency at all. Its a shame because I am (one of the few, it seems) who really enjoys the unique way a CVT feels in a car and its a gearbox I have always been a huge fan of!
i would use a stepper motor to control the transmission, an alternator for the generator so i can manipulate the magnetic field and use a raspberry pi or simular as management.... just not sure what turbine i would use for it.... would love to see you build something like that. i really enjoy your channel and started experimenting with turbines again thanks to you
A really great review of CVT! Well done!
I love that ! It reminde's me an other marvelous thing that could maybe somehow connect, the "régulateur d'allure" (in dont know if there is an EN translation sorry) invented by a crazy navigator ...(Moitessier if i remember well..) In the wind turbine case, the "regulating thing" could be some electromagnetic field transmitted from the turbine to adjust the gearing ratio?
Wow i had now idea the CVT went back so far! Great video as always, Rob!
Also hitting on a whole range of variable speed transmissions, with patents over 100 years old! I still haven't seen anything on using radiating shafts on an axel, with counterweights, which would be able to change the shaft size with centrifugal force - also something I've been milling over. It's a brilliant idea and would be very useful in wind generators, where you could keep the turbine/blades running at a constant speed, but vary the torque, depending on the wind force... there's a 100 year old patent on that, too, isn't there?
Excellent waistcoat and long coat ❤
Sounds like something to be pondered... on the golf course! (or on the 19th hole) 👍
So if you turned it on it's side, would the natural propensity for the golf ball to be attracted downwards by gravity be overcompensated by the speed of the turbine - ie. would it want to raise upwards (to an 'easier' ratio) as the speed of the input increases? (I suspect not but might be an interesting test)