Magnetic Gears - Why Nobody Talks About This?
2022 ж. 26 Там.
3 116 024 Рет қаралды
How about instead of a physical-contact gear meshing, a magnetic meshing by permanent magnets?
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Magnetic gears has an engagement that is completely non-contact through magnetic forces, which gives them many advantages, such as much quieter(!) and lubrication-free operation.
One of the reasons these would not see widespread use is reduced efficiency due to eddy-current losses within any nearby metal components, and you would want a low reluctance metal housing to ensure you don’t induce voltages into nearby wires.
@Jeremy Karst. This is what magnetic shielding is for. You know those little speakers that sit next to your computer. You noticed they don't affect your screen. Magnetic shielding preventing magnetic fields from escaping
@@jerichojoe307 I'm pretty sure the amount of current going though a standard speaker isn't large enough to matter, considering I've never added any type of shielding to any speakers I've made.
@@Gorgonzeye it mostly applies to old CRT displays as far as I know. But the point still stands. Just not the greatest example.
@@Gorgonzeye the amount of current going through the speaker isn't what I'm referring to here. The speaker itself has a toroidal magnetic field around it even when it's not hooked up just like the static magnets that he is using. Like the guy below commented it may not have been a good example as it only applied to certain types of screens; but it still applies to the point of preventing the magnetic field leakage inducing current in things around it or affecting things that are magnetically sensitive. Many motors still use shielded housings to surround the motor to prevent such things as current passes through the coils of the motor. Whether it is electromagnetic field or a freestanding magnetic field; simple shielding would prevent what you initially proposed. He is not feeding any current to the gearbox. He's feeding current to the motor that is attached to the gearbox which already meets proper standards and wouldn't require such shielding but the gearbox still does because of its magnets. And even that would depend on the gauss rating of the magnet and how far out the rotating magnetic field could affect things or induce current. I mean think about it. There's a very large rotating electromagnetic field generator inside of your car called an alternator; but you don't see that inducing currents that interfere with any of the electrical functions of your vehicle do you 🤷 my brushless bldc impact driver has some pretty powerful magnets inside the motor but I don't see that so much as disrupting any functions of my cell phone while using it right next to it or while working on a metal door. a magnetic field has to be very close to another metal or very strong to induce currents in surrounding wires or metals, so shielding is not always necessary depending on the strength of the magnet but if it were necessary it would be a very simple solution.
@@jerichojoe307 the problem the original comment tryed to point out is that BECAUSE we need shielding the magned will lose energy into the shielding and isn't transferig it into the other gear while the other gear is losing energy it receives because it is inducing part of it into the shielding and not into rotational energy. that means we have losses in the first gear AND in the second gear. and you would need electro magnets because permament magnets lose slowly their magnetic field when it's magnetic field gets moved. thze next problem is that you can't accelerate or decellerate these gears fast because they would slip if the jerk is strong enough and it takes way less than for normal gears. the same applies to load on the second gear. if the load is too high the second gear won't move and you need REALLY strong magnets to move the same loads normal gears take without problems. like he shows at 10:00
One of the big issues with these is their load bearing capabilities. Unlike a regular gear these will not be rigid under load, which is fine for some applications, but they can't really be used in applications where you cannot have chatter unless you combine them with some kind of active load balancing from an electromagnet. Very useful if you want to rotate something inside of a sealed container.
Or even wanted. No tooth wear. Plus bigger loads could be supported with stronger magnets. Force ratings.
@@thermostance1815 also, the load capability is inversely proportion to the distance between magnets. Using a better and more rigid build with tight tolerances could make it exponentially more effective
Hermetically sealed motors have existed for over 75 years, they don't require any magnetic parts, and there isn't even a necessity for sealed driveshafts after the Zero Axial Radial Thrust technology was created. This guy is making stuff in the Dark Ages compared to what actually exists in the world market today.
@@ryanmitchell6721 And fixing problems that don't exist except in 3d printed parts. Ground helical gears aren't noisy, and have negligible wear because they are rolling on each other instead of sliding. The load capacity of a magnetic gear drive will be laughable in comparison to a similar size or weight gear drive and cost way more. A fun project and interesting ideas, but hardly fixing gears.
@@ryanmitchell6721 your 75 year old motor also requires electric power to make torque. Why add more inefficiency during a energy crisis? This is a cool demo of old technology but unfortunately we don't live in the reality of a freshman year physics class.
What a beautifully detailed video. This felt like a university level report on a personal project. Really enjoyed the details, the discussion, and the examples. Gave me some good ideas for possible future projects. Thanks for such a high quality video report on this project!
We actually do see magnetic gears in limited applications, though their practical use is mostly for things where high speed low maintenance designs or inherently safe designs are required. In most cases they are used in hazardous material handling where shaft seals could be a major and rapid point of failure in a system where chemical leaking is incredibly hazardous to both life and the environment. Usually you see this used with a 1:1 ratio in magdrive pumps. They lack the flux motivator and instead work as a simple magnetic coupling, but they are still a power transmission with an input and output that closely resemble your designs. They are also used in some applications where wear-less torque limiting is required, such as found in some scientific and industrial machines. They are a good tool that is over 100 years old, their continued use today despite their age proves they have a practical purpose. They are not a replacement for a mechanical coupling however. Their torque is limited, efficiency loss can be quite large depending on design, and their effectiveness as a power transmission is highly dependent on the quality of design. There is potential for use in renewable energy systems such as wind turbines where a maintenance free gearbox could reduce both manufacturing and maintenance costs. Current gearboxes in wind turbines will far outlast the actual structure of the turbine itself, however the gear oil must be changed at least once every three years, in the average lifetime of a wind turbine the gear oil will be changed 7 times. Each oil change requires 50 to 200 gallons of oil depending on turbine size with larger turbines requiring more oil than smaller turbines. While this isn't a large amount of oil for a single turbine, about 1,400 gallons of oil over 20 years for the largest commercial turbines. It adds up quickly when you have 20 or more turbines in a farm, which is 28,000 gallons of oil over their lifetime for a 20 turbine farm, or just under 3 semi truck loads of oil. If used for gasoline this would come to about 20,000 to 24,000 gallons of gasoline, which for understanding of scale would power a modern car could drive 800,000 miles on the oil required for 20 large wind turbines in a 20 year life. While we aren't burning the oil in the wind turbine, we still need to distillate it from crude oil which still necessitates drilling for oil and disposing of the waste oil (which is often burned in peak demand oil power plants or sometimes refined again into another lubricant). They may also see use in salt water environments, where shaft seals going bad will result in the failure of the device. Removing the shaft seal represents the removal of a high wear component from a system that cannot be easily treated to resist corrosion like sealed bearings. Bearings designed for underwater use are often made of stainless steel that are highly resistant to corrosion even when the metal surface is directly exposed to salt water. In the case of underwater gearboxes the motor itself will always be susceptible to damage from water ingress, removing the shaft seal often represents removing the only moving seal that is exposed to mechanical wear. All other penetrations into the motor casing are non-moving and can be sealed comparatively easily.
Well said good sir
The torque in wind turbines is enormous, a magnetic gearbox might slip under medium to max power. Not sure if it is right, but I did the math for a 2MW turbine and the result was 19 million Nm/14 million ftlb
@@Isgolo Thats not quite right, The largest commercial deployment is a 9.5MW turbine. Hold on, i'm about to geek out a little because I don't want to do homework for a boring as hell project management class right now. At theoretical max power production 12,700HP, at 10RPM (about the max rotational speed for a turbine this size), we get a torque value of 6.6 million ft-lbs (9 million newton meter). That sounds like a lot of torque, and it is. There are some research papers that test axial magnetic coupling (just as a reference) and a single 200cm x 6cm mag drive shaft is capable of a max torque of 4,200Nm in testing for example, take the next 3cm radius slice and you add another 11,000Nm for a total of 15,000Nm for a magnetic coupling 200cm x 9cm. Already an increase in diameter of 50% increased coupling by 350% and we are still only at 9cm magnet diameter. Taking the coupling size up a few notches (factoring non-linearity of distance and equivalent force) we are at 2 million nm for a coupling 2m x 2m. To get our 9 million Nm we would need a coupling about 3.8m x 2m diameter. Thats huge, but it still fits nicely inside the 9x8x20 meter housing on the 9.5MW turbine. This is all just napkin math, chances are I am seriously underestimating the amount of force generated, but I am only using some of the more basic generated equations from the research paper (basic is relative, some of the simpler ones still have 10 terms). Given we can get about max torque from a magnetic coupling that size with no reduction, we could just be conservative and say the actual size for a 4:1 reduction like achieved in the video is twice that diameter and a little deeper. 8m x 3m is a rough estimate without going back through and doing everything all over again with an increased air-gap. Once we get past the first reduction we are only talking a torque of 2 million Nm, which we found earlier can be handled by a 2x2 coupling. Since most wind turbines run a generator speed around 1800rpm, we need some more reductions, essentially a 180:1. We only need three 4:1 reductions and a 3:1 reduction. The required torque values and aprox. sized for each stage are as follows. Stage 1 - required stage coupling torque 9MNm - est size 8m x 3m - total reduction 4:1 | Stage 2 - required stage coupling torque 2.2MNm - est size 4m x3m - total reduction 16:1 | Stage 3 - required stage coupling torque 560kNm - est size 4m x 1m - total reduction 64:1 | Stage 4 - required stage coupling torque 190kNm - est size 2m x 1m - total reduction 192:1 - final stage output torque 47kNm at 1920rpm at 9.5MW or 12,700HP. The total estimated length of our gear reduction would be about 8m, which still leaves 12m for the rest of the equipment inside the nacelle. Is it possible? Maybe, thats a lof of iron boron magnet required. It's possible they could experiment with excitation style stators with permanent magnet rotors like three phase brushless motors. While that would eat into the power generation of the turbine, it would greatly reduce the rare earth metal requirement and replace it with iron and copper, which IMO is still a good tradeoff as it increases the sustainability of the turbine even at reduced efficiency. Truth be told I don't actually know if it's possible, these number are for a highly unoptimized coupling setup, there is no fancy design it's just magnets cut like a pie around a disk in a N-S-N-S-N configuration. There is also the possibility of the 4:1 and 3:1 reductions not being optimal, maybe 5:1 is better, or 3:1 is best. I don't honestly know. But with ballpark numbers it looks close and sounds reasonable enough based on the testing done for the paper. I know magnets are weak, but we are still talking about a first stage reduction thats almost 20ft diameter and 12ft long.
@@2009dudeman I thoroughly enjoyed reading this, thanks!!
Well said
I noticed a lot of small water pumps and generators use magnetic coupling to keep the electrical parts sealed; there’s no shaft coming from the motor that needs a seal that will eventually fail. They aren’t using magnetic gearing but it seems like a good place to apply the use of them if needed since there’s already magnetic coupling limiting the force that can be applied to the output by the motor anyways.
still needs bearings
And underwater diving scooters..
Came to mention the same. Mag coupling is quite common in many applications.
isn't that just induction rather than gearing? I haven't seen any pumps with actual gearing inside, they are just like any other motor, but with a thin plastic barrier between the stator and motor for water proofing. I've only dealt with small pumps for liquid cooling and etc, do larger pumps have actual gearing?
@@HicSvntDracones induction refers to a changing magnetic field inducing a voltage into an object.
Coming from a cycling background. A great application of this is the Kurt Kinetic Fluid Trainer. The resistance unit/fluid chamber and fan is completely sealed up and never leaks. A magnetic gear transfers the force.
I love this please keep pursuing this!! Your explanations are very easy to follow and entertaining
Very interesting video. This magnetic driving technique has been used for years with water pumps in fish tanks etc. However, I am really appreciating your explanation of how the magnetic field can be used to form a gear ratio... very well done! (Subscribed!)
Me too!
It also drives the electronics on every car youve ever ridden in, any motorcycle you've ever seen.. Alternators and Stators. this is .... "Ancient " tech by todays standards..
Your production value is crazy. I can't imagine how long this video took to put together, it looks amazing
lol
@@TheGFS lmfao rofl smh imo
What production value?
Agreed but also it sounds like hes under a pillow with a big sucker in his mouth reading the script
Sound quality is so bad, i clicked away
Wow, you did a great job visualizing and explaining everything! I'd never heard of using ferrous, non-magnetized components to redirect the field lines of permanent magnets like that. That is such a cool idea! Watching this, I couldn't help but wonder if the rolling element bearings couldn't also be replaced with either some manner of magnetic suspension (which might interfere with the other magnets, idk), or a fluid bearing that takes advantage of the high rotation speeds in order to create an air cushion between the axel and the... whatever you call the thing that holds the axel in place.
Nope. Not unless you were going to have actively controlled magnetic bearings. It is impossible to make a static magnetic structure that levitates. There is always at least one axis of instability.
@@bpark10001 But this spins. Wouldn't that satisfy Earnshaw's theorem?
@@hollt693 I assume you are referring to the Levitron Top (maintaining levitation by spinning). No. First, have you ever worked with the Levitron top? Its equilibrium is so marginal that the slightest change of room temperature or a puff of wind will send it flying! It requires 20 minutes of tweaking weights (on the order of 1% of the top's mass) & leveling to fractions of a degree. Secondly, it cannot support any side-forces that would be imposed by things the machine is driving, nor acceleration forces. In addition, the side-forces imposed by the magnetic gearing (which are ~10x larger than the torque-producing forces) would also add to the forces the magnetic bearing would need to counter. And what would you do when the motor stopped? Get a Levitron & report back! It must be practical from an ENGINEERING perspective, not just a scientific one.
@@bpark10001 That's fair. I do have a Levitron around here somewhere, but I haven't played with it in years. What you're saying makes sense, though. The output shaft would definitely require more stability than what could be achieved with passive magnetic levitation. Even if you could add a big ol' flywheel onto the shaft for some sort of gyroscopic stabilization, the procession would be undesirable at best. Huh. Dang it.
Excellent tutorial. Your explanations are useful to both the lay person and expert. Well done.
I love your use of magnetic viewing film here, it makes the moving fields much more clear! I wonder if just a plain steel ring outside could focus the magnetic field almost as well as a Halbach array? Most brushless rotors seem to use just a 1-2mm thick steel ring outside the magnets, to capture the flux that would otherwise dissipate out. Increasing the amount of magnetic material in the crucial middle piece, and decreasing the gaps, might increase the flux linkage and hence torque too...
Yes, a plain steel back-iron would work.
Wouldn’t the rotation cause it to heat up?
@@tripodal69 Because the field of the outer ring is constant (created by permanent magnets, not coils) eddy current losses are not a big concern and plain steel should work... but anything would be better than nothing.
Yes it certainly would!
If you apply a voltage to the central gear, and attach it to a rheostatic variator, it should be fairly easy to alter the magnetic flux of the central gear to allow it to slip more or slip less of the input and output gears, thus acting as an electric torque converter. I've had almost the same design drawn up.
Genius! Way better than modern day transmissions! But once we switch to electric motors transmissions won’t be really needed on vehicles
aha, I just commented such. I been working on plans in my head for a few years. I might even have some in my computer 3D. I wonder where they went.🤔 Actually, my design was to use elecro reversing pole set up.
This is so cool! Please keep experimenting with this concept!
so fascinating I can't wait for the next video with the different magnet arrangement
Because it uses magnetic field to drive the output shaft, it is very similar to a motor.. The best results you will ever be able to get are likely as bad as stepper motors. Like stepper, you can increase the strenghts by making it longer. Double the length : double the strength. I 'd like to see it used in reverse, to up the speed
yeah because electric motors already have a lot of talk so the could achieve very high speed with gears. The talk is evenly spread throughout the rpm range as opposed to a combustion engine where the talk is only in certain hot spots. Talk is the best way to get around these days. nice talk-ing to you.
I think that with the Holbach array and tighter tolerances you could get some quite good, and usable results. Great video. Keep up the good work.
Really great job. You explained things very well. Fascinating what magnets can do. Keep up the good work!
I had a hard time understanding his english and had to abort. Bad sound quality maybe FIX it with better mic and english courses
You really nailed the principle of magnetic gearing. I learned a lot from this video. So, what kinds of applications do you see this magnetic gearbox for?
Hey, I am a PhD student who is focused on the design, analysis and construction of magnetic gears. You did a great job with explaining and demonstrating some of the concepts! However, there are some flaws I can see in your design. If you want any advice for future prototypes, let me know!
Can you give us any references to good papers on the subject? And maybe write a bit about construction techniques and the challenges? Are the designs purely permanent magnet based, or are there designs that work more like an integrated alternator/motor setup?
@@dave7038 no such thing as a free lunch Dave. Realize you just asked this guy to practice his trade, for free, for you, for NO REASON. You sit with the worlds most powerful information indexing system at the tips of your fingers yet here you are pumping someone on youtube to do your work for you? Shameful.
@@wrongfootmcgee You have to be american...
@@wrongfootmcgee Shrug. Some people enjoy sharing their knowledge on things they are studying. In fact, there's a whole website dedicated to letting people share videos about things they're interested in!
@@wrongfootmcgee It's not up to you to decide, if he want to share his knowledge or not
I find this incredibly interesting and I hope you’ll continue to experiment and post them on KZhead.
I had an old fax machine that used magnetic reduction to drive the drum. There was a 4 pole rotating magnet, a flux guide, & an outer steel internal gear. The construction resembled a harmonic "wave" drive, in that the flux guide & the outer gear differed by 4 teeth.
We've been using magnetic drive pumps in the beverage industry for ages. Pump, and motor have zero physical coupling. It can transfer plenty of torque to build enough pressure to blow apart tubing if there is a restriction
Absolutely fascinating video! Something I had never thought of but considering the implementation of servos, linear motors, and the like, I suppose this is a natural application as well. I'm sure there are situations where this sort of use is already in place (high speed / low torque / need for overtorque protection). Thanks for putting this together and explaining everything in a very clear manor. Bravo!
Well, that is pretty amazing, never heard of these before. Thanks for the video Retsetman, and please do more !
i love that droning sound it makes
Your animations and explanation of the concept are outstanding in this video. Brilliant stuff. 🤔
One application I thought of is the slip could be used to generate a vibration while being balanced. Compared to most uses like a concrete mix vibrator that utilizes unbalance weight to induce the vibrations. Could also be an excellent safety feature for machines with human interaction. I look at it almost like a double electric motor / generator. Great video:)
Pretty neat! Would be interesting to see how much of a reduction you could get with a multi-stage approach
This ist something similar: kzhead.info/sun/odJ6dZSgqJl-aZE/bejne.html&ab_channel=HiddenTechnology
Dang, that's awesome. I was just talking to my friends about how magnets could be use to generate power. Then this video comes on my feed? I love it. Thank you for the awesome video!!
Magnetic gears have been around forever. My grandfather built a little gearbox with magnetic coupling well over half a century ago and we still have it kicking around somewhere. Magnetic gearing isn't used because it's INCREDIBLY expensive and bulky for the amount of torque it can transmit. A much cheaper and stronger gearbox can be built with conventional mechanical gears.
Direct drive is much simpler and has the same inherent overload protection. I don't see why the magnetic interaction in the gearbox would ever be more powerful than the magnetic interaction in a motor of the same diameter.
you could use a system like this to get a stepper style motor to go fast and it would integrate well, but their is a reason nobody talks about them.
@@lizelive a "stepper style motor" would cause plane to crash
@@lizelive Stepper motors aren't designed for that high rpm application they're meant for dead accurate step positioning when used with servo feedback, what you want is a modern BLDC motor.
100% correct. there is no use for magnetic gears unless for some reason you need you cannot change the motor and at the same time need the drive and gearbox to be isolated. very niche.
@@Professor-Scientist nobody mentioned a plane tho?
Very Interesting project and well done! thank you for sharing!
This channel is way under rated.. keep going bro I hope you a million subscriber
Had been thinking about this idea for a couple days. Never talked about it. But now it’s on my feed😂
There will be niche applications for this, but it cannot replace most gear situations. Great video!
literally the first time weve seen this built and you are already saying it wont replace current tech. lucky you arent in charge of any innovation!
I think chemists use something like this to stir when mixing some solutions and shit.
Wow.. thanks talking about this. I’ve seen this design also in pump for corrosive liquids. The impeller rotor is engaged with external motor through magnetic coupling to prevent direct contact from liquid to motor. But yeah, utilizing it as “planet gear” is something I’ve just seen here.
Good ol' Magnatex pumps, used to work with them when I worked in the chemical industry
Immersion pumps in general work like that. The stator is sealed in a plastic housing, away from the water, and the impeller has a permanent magnet attached that serves as the rotor.
Literally every week I see a video in my recommended about how magnetic gears are the best thing ever and no one talks about it... is that just my algorithm? or is that many people are talking about magnetic gears?
I have a truck mounted carpet cleaning machine. It uses a magnetic flow switch. A piston (or shuttle) flow switch is designed so that a free-floating magnetic piston responds to the amount of flow within a pipe. When there is an increase or a decrease in the flow rate, movement of the piston actuates a hermetically sealed reed switch, triggering the specified action. When it works it's good, but they do wear out. You can replace the magnets and the shaft casing all you want, they eventually break. They need to be replaced every 3 months. It might not be a magnetic gear but this is a real life example of a magnetic device in an application that can be very unreliable at times. However, you do some interesting stuff.
to answer your question: "Why no-one talks about this?" -- very simple. It is physically impossible to make a magnetic gear system that has more output torque than a motor of the same size and geometry can generate on its own without gearing. In fact, due to the much higher flux density of electrically energised ferromagnetic materials (2T vs 0.4T for the best permanent magnets) a properly designed electric motor will significantly outperform any passive magnetic gearing in the same space. So why have a motor and a weak magnetic gear when just a motor would be 5 times better? or 25 times better? (since magnetic force is the product of the two flux densities, if both rotor and stator are electromagnets it can be 5 x 5 times stronger). For this reason, magnetic gears will remain only a curiosity.
magnetic gears are already being used though, in sealed couplings for example in numerous industries or in hazardous materials handling or high vacuum or high contaminant sensitivity applications where gear oils/grease could contaminate through outgassing. A factory I worked in used these exclusively for pumping highly flammable liquids in order to completely seal and isolate the flammable and electrical side of things, so there's tons of applications where these are very practical to use and are already an industry standard.
@@platinumsky845 Absolutely, for these applications the advantages outweigh the disadvantages. Usually they dion't
this dude is right
Cmon dude they do have a practical use and they are used probably from before I was born.
Wonderful sharing! Super excited to see some cooperation going between us🤝
I need a part 2 to this!
Love the result in the ending!!😂👍👍👍
A promising idea. I'd like to see how far you can take it. I want to see this with the hallbach arrays and smaller air gaps and shaped iron instead of screws etc.
That’s really interesting. I’m curious if you get cogging of the output in response to a smooth input gear speed.
I think a design based on a stepper motor configuration might make lots more torque and variable torque. Good video. I liked it.
Loving the video. It it you use a green filter with what likes like a ferrofluid or ferrous material in it, what is it called?
You've reminded me of magnetic transitions just as I saw video on iron nitride magnets. Iron nitride magnets can be almost 3x as strong as neodymium ones, while not using any rare earth materials. This means that you could make magnetic transitions in bulk, and even mount them in normal, every day devices.
That's funny. My research team works on iron nitride nano magnets. I smiled when I read this comment 😁.
Yeah - and have far more expensive, heavy and inefficient devices.
@@ABaumstumpf Iron nitride has lower density than steel and you only need it on very tips of gears. Rest of gear could be made of plastic or really thin metal, because you would have to fight very high forces caused by hard steel meshing. They also are nearly lossless transitions, so in fact you could have lighter and more efficient device, with similar or lower cost - no heavy machining required and magnets would be mass produced and slotted/molded into place.
@@michahalczuk9071 while I like your optimism, I do feel like you're skipping over a few things. Cost of manufacture. Making an ABS of Nylon cog is going to be cheaper than making magnets which then have to be put into an ABS of Nylon carrier. As you're adding the entire step of manufacturing the magnet, as well as complicating the assembly process by having to insert the magnets. Adding complexity like that, adds costs. The carrier needs to be robust enough to withstand the forces in the gearbox, regardless of how those forces are transmitted. So the carrier can't be thinner than the plastic or metal cog equivalent. Especially in cheaper consumer grade products, those cogs and gearboxes are engineered down to the hundredth of a cent, they're not wasting raw materials that they don't have to. They've already removed all the material they can without having the product fail during regular use. Heavy machining is rare these days, especially for mass produced goods. It's very uncommon for DIY power tools for instance to have machined gears rather than sintered metal gears or even just injection molded plastic gears. If the Iron Nitride magnets are significantly cheaper than Neodymium magnets, the companies that now use Neodymium will just switch over to Iron Nitride to save on costs. And last but not least, what would their application be? It'd have to be something where a hermetic seal is required, otherwise why bother with a magnetic coupling to begin with? And in that case, it'd also have to be an application where it's impossible, even with a VFD or PWM to get the motor to spin at the desired RPM.
@@fermitupoupon1754 I think you mistook my thinking of making mostly toy transmissions with those magnets. I was talking about generally electric cars where mostly you will still need to gear down motors for greater power and efficiency (and smoothness). EVs generally use helical metal gears which have to be machined for higher precision and lower noise. Because they mesh hard metal on metal the peak forces are much greater than average forces you would encounter if the meshing was soft - magnetic. Your transmission still has to resist those peak forces and vibrations without damage, this requiring much stronger material than one needed for just average forces. This would mean you could possibly replace steel helical gears with plastic/aluminum ones that only have to be molded. I'm also not talking about gear shown in the video, since it's probably the worst example of magnetic gears. Magnetic gears that are made to look like normal ones but mesh with magnets. They don't have release torque because repelling force between magnets very sharply gets stronger. Iron nitride magnets also don't contain any rare metals and are very easy to make, making them potentially perfect for such applications. You also can magnetize then in place, which means that you could easily mass produced, molded in place for example, and magnetized later. If such magnetic transmission increased efficiency of electric car by 2% for more or less similar cost it would be well worth it. Tesla recently made a change of motor, to one using more expensive materials which overall lowered cost of production and increased value of their Model 3 because of higher efficiency. Similar would happen to magnetic transmissions if they just were good enough. With iron nitride magnets they well could be.
Would be interesting to see what different shape magnets could do in regards to their opposing fields and using smaller magnets closer together would reduce noise and vibration Might result in better torque too.
I hope there is an upgraded version video. This was very entertaining.
Great video bud.. keep up the good work 👍
Put three or four of these in parallel, but out of phase, so there's always one of the three pushing whilst the other two are in some phase of 'slipping', then you've got relatively steady torque even down to zero speed, without damage. Also, it looks like that 'lumpiness' carries over to all speeds, so setting it up that would should make it turn smoother at all other speeds too.
Rather than putting several in parallel, the practical solution is to spiral the gear "teeth".
@@Nathan511 Sure. that's ideal. Probably easier to do with the intermediaries, if they're made in lamination slices that can be assembled with a stagger: similar to how you get rid of the cogging in a motor. Ideally, the magnets would be too: however, I don't know of any manufacturers who offer them in the right shape for that, so you'd have to give them a similar shifted-lamination-slice magnetic steel 'guide' to put the flux where you want it (ie, mount the magnets within the 'guide', sections: slices would have the cutout for the magnets shifted so they line up to make a slot for the magnet to sit in, when assembled with the designed 'stagger').
The torque would probably rule these out most purposes. This goes more or less into a sort of sensory array. And for this we have hall sensors already. Probably that is why ..? But great project and very nice idea. Something unusual!
Don't Engineers choose technologies based on requirements?
If you make a magnetic torque converter which would just be an induction motor with a permanent magnet stator, you could get a lot more torque. But I'm not sure if it would outperform the traditional hydraulic torque converters. The only advantage would be less maintenance.
@@Stoney3K eddy current clutch.....the motor spins at a constant speed the output shaft of the motor and the output shaft of the clutch are connected to 2 drum shaped metal parts that never touch and are coupled by a magnetic field that's adjustable.....
Great detail! Very interesting and informative.
Your example is brilliant.
I don't imagine that a magnetic gear like this is able to handle really high torque, but in low torque applications, it should work quite nicely. And of course, there's the aspect of potential uses in situations where a seal might be needed. One of the more common examples I've seen of that are Lego submarines, where magnetic coupling is used to protect the electronics yet still allow for propulsion.
Very interesting article ... Thanks for sharing.... It reminds me of outrunner brushless motor, where electrical current in coils replaced by rotating magnits. These motors sometimes loose sync like what happened in the video when u suddenly increased motor speed.... Many thanks.... Very inspiring video.
this is very useful on mulit-color printing, can control the filament spool collect filament back when changing colors.
I hardly understood this, but it was still fairly interesting. Thank you.
In addition to going to a Halbach array, it would be useful to have the magnets butted up right next to each other. This would reduce the effective air gap and should increase the torque. The field modulators probably should be soft iron bars rather than whatever those screws are made out of, and again try to reduce the air gap between the 3 rings. Also, use some locknuts - in the high speed test, you can see the nuts working their way out - LOL. This was a very interesting and entertaining film - you don't usually see innovation in mechanics like this.or to fill the air gaps in each ring with a permeable material
Cool demonstration ☺️ You expressed surprise about the noise, and I was wondering if this right here 9:01 shows (part of) the cause. It doesn't spin at a constant speed, because of the very nature by which push and pull works the system. That causes the whole thing to vibrate and as such make a noise.
Great video man....idk exactly what I was expecting, what I DO KNOW....is you dam sure exceeded them!!! For real...Tip top, on info, and presentation!!
Fantastic. Mind blowing apparatchik. Thanks 3dprintworks
Very interesting project. I wonder what effects changing the moderators in service would have? Could such things as moving the moderators in or out or having mixed permeability or laterally movable or even changing the number have any useful effects, such as changing gear ratios?
This is also interesting project: kzhead.info/sun/odJ6dZSgqJl-aZE/bejne.html&ab_channel=HiddenTechnology
really cool stuff! what would happen if it had a load on it though? I imagine once you add a propeller onto it the losses would become quite a bit greater
It would simply be useless.
Excellent work and quality video. Thank you very much for sharing.
That is just absolutely beautiful.
That's awesome! I'd love to see you make one with closer tolerances. I know that Tesla is getting more power out of it's motors by having incredibly small spacing between magnets. It stands to reason that you could get the same result here (I think). Obviously, it's hard to get precision with 3d printing, but maybe a bit less gap. Or maybe talk to another creator and see if they can turn something out of wood or PVC on a lathe?
I love it! I would love to see if you could increase the torque. Another cool project would be to make a fan out of this?
@@anothermidlifecrisis you are right but there are ways to increase the magnetic coupling. have some ferromagnetic core or laminated structure. Maybe stronger magnets? better magnet layouts... it just seems fun to experiment with those
I was waiting for that practicality at the end... You said it I laughed too.
Would it be possible to not have internal rotation use bearings or have any point of contact at all? I'm thinking what if you used the same polarity magnets to push the ring away, but you'll also have the same happening on the other side as well. If this isn't possible, I'm assuming it's because magnetic fields would be affecting the produced rotation. Not sure if this makes sense. The magnets pushing away would be round instead of rectangular, but I don't know.
Very interesting work, thank you for sharing. It seems that a halbach array on the sun and ring are a good idea to improve max torque. Would reducing the airgaps between Sun/Flux modulator and Flux modulator/Ring improve max torque? What about going to square or pie cross section metal in the flux modulator, to help reduce the effective air gap? Motors and generators use laminates instead of solid elements to reduce eddy losses, I believe, so I also wonder what replacing the screws on the flux modulator with pie shaped laminates would do? Not easy to make though. Regarding losses, your first test was unloaded, so I'm wondering if the eddy losses increase as load is increased, and then one would start to see temperature rise in the flux modulator elements?
You are correct. I am short the right size set screws but I have a 3d printed project but I am using a halbach array and even without the set screws to modulate it is fairly strong and I am interested in the idea of adding laminates as you suggested. I am attempting to edit another file to create a magnetic 608 bearing using very small magnets which is proving much harder. My printers resolution seems to be limiting me atm. My projects are all about being small though. Though sizing them up digitally should be possible.
@@TheWeaponshold Maybe design the parts so they can be printed in vase mode and have only 1 layer for each feature in the radial direction? From what I can see, that would get rid of at least 4 layers that are pushing each component further apart. Then use set screws or pins in place of the machine screws to get rid of the heads that are also pushing everything further apart. That would allow for the air gaps to get much smaller.
Do a follow up video! This is super interesting! What else can be done to maximize the transmissible torque? What if all the magnets were closer together? What if you applied power to the faster side, and stepped down the speed? Is the torque better?
I wish you did this with like very precisely CNC stuff... so it all fits perfectly and the weight balance is perfect too. I bet it would be very quiet and because of the smaller gap it would also become stronger.
They're not used because it is trying to solve a problem we don't have. Basically, this is reinventing the wheel and making it more complicated.
Hey I'm curious. What happens if you add 1 screw to the planetary rotor, and 2 permanent magnets to the sun rotor?
This is a great video. Keep on keeping on.
Weird...I was Thinking about this concept last night in a different way...now this is at the top of my feed
You can dramatically increase the magnetic Flux if you use the proper metals which amplify the flux. The best is vacoflux50. It can increase Flux by 1000 times since it completely redirects it to the desired location and doesn't allow leakage. It also has the lowest loses from hysteresis and eddy currents. The hallbeck array will definitely help as well.
thats a funny name
What if you shaped magnetic gears such that they have teeth but they are small enough that they normally don't interact unless the magnetic coupling fails? Or you place magnets in the teeth (similarly too small to typically interact) such that as the magnets get closer under higher load they apply more force to avoid contact. Maybe this causes too much binding with the magnets, but it'd be interesting
In the case that they did interact one of the gears would have to be off center if the teeth aren't normally in contact. At best this would cause strain on the mechanism. In most cases it would also add a lot of jittery and wouldn't allow for smooth rotation.
Very subtle, especially at the end.
Awesome. Genuinely amazing video with really in depth explanations. Glad I got this recommendation. Earned my sub 👍
I'd be surprised if this system is not already in use. It's so simple and has many positive characteristics. No doubt the 3D printed parts without balancing doesn't allow full potential. Very creative project!
I think it's very interesting. I would use it for robots that work with human as a protection for over torque. In cnc I would use it as sensorless endstop cnc. It's very promising. A question, does the permanent magnet lose magnetic force over time? And if yes, is big ? There must be a formula for that. Thanks for sharing
Sure they lose power over time. Though I think it may take a few million years for it to be a measurable amount...
Awesome, without your explanation I would have been a little lost. You've got me subbed!!
I love how Yoda impersonating Kermit the Frog made something this fascinating
I'm not even a mechanical engineer or in a related field and I've heard of magnetic gears many times before. This is far from an uncommon topic or new concept. They are not commonly used though because the applications are limited and conventional gears are often the superior option.
The only things I got out of this video was (1) how a guy who makes a lot of 3D printed gears figures he can make an improvement on 3D printed gears and (2) how he has absolutely no clue how real helical, herringbone and other modern hardened steel gears actually work. Oh, and a plastic ring with a bunch of screws inserted into it is suddenly called a "flux converter".
Bit of a bugger but "Flux Capacitor" had already been used!
This idea could be applied to a cycloidal/harmonic arrangement for high ratio compact low torque box. Having a box that can slip damage free but is synchronous during operation seems like a cool thing, especially at a high ratio. A high field flexible magnet printable/cutable material would be cool applied to any of these magnetic gear concepts.
What a plot twist at 11:45 LOL
you've answered the title question yourself. nobody talks about this because of how incredibly limited usefulness magnetic gears have. as you've demonstrated in the video, the gears start slipping at the hint of load. that make it only good for low to micro torque applications. but guess who's worried about wear and tear on normal gears in low torque mechanisms? no one. so yeah. magnetic gears are more useful as youtube video ideas.
that is very very innovative. Keep up that mad science work !
Thank you for a great video on an intersting topic.
whats the output torque before it starts to slip ?
Thanks. Start up torque is a big problem. Vfd needed and no sudden load increase.
I had no idea you did these videos and one of the best warzone players out there!
The magnetic contacts will be fine for the freely rotating gear shaft that does not drive an output shaft with a load attached. As soon as you are going to have to drive a usable load, you are going to have a lot of slippage. Slippage will also occur due to inertia when the drive motor stops and the load keeps rotating. You can see the slippage in your video already even when no loads are attached.
These are amazing insights!!
Thank you for all the time you put into showing and explaining everything!! Forgot how cool it is to watch electromagnetic capabilities in action
You're a true master in this topic. I've been in the mind of a genius. Thank you.