AGCO's Continuously Variable Transmission (CVT) Explained
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- čas přidán 21. 08. 2024
- AGCO was the first company to introduce the Continuously Variable Transmission (CVT) for agricultural products. It is the only true step-less transmission in the agricultural market today. While the CVT is superior in efficiently transferring power to the ground, the largest benefit is realized when operators can throttle-down and speed-up offering market-leading production and fuel efficiencies. #agcocorp
Wow! I've been a truck and heavy equipment mechanic for 30+ years so I've worked on lots of different types of transmissions. From hydrostatic to gear. And this is one smart set up. So simple but very smart. It should be used in more than argos.
There are many types of CVT. Some use belts and pulleys, toroidal disks, or tilting spheres, and others are purely hydraulic. This transmission is part of the CVT subclassification IVT, do to its ability to reach a neutral and reverse gear ratio. All variable displacement hydrostatic transmissions, regardless of configuration, fall into this subclass of transmission.
AGCO has bought Fendt in 1997. That is why it shows this video under AGCO brand.
Thank you this is SOOO simple and elegant as to have gobsmacked me....
Refreshingly simple, I thought this was a parallel rev-matching adder system like Mitsubishi defense uses in their Hitomaru tank. Very cool
got it after watching aproximately 20 times ))). But it's amazing ! It's simple mechanical CVT ! I want it on my car !
One question, does this transmission have any actions to change gear ratios like some other tractor cvts?
@@jacktackfly8838 no, as shown in the video it's all hydraulic
@@jacktackfly8838 it has a high and low range. Low for in the field, high for on the road. Not something that shifts in and out, but the user chooses what they want before moving.
@@tangydiesel1886 ahh i see, tnx
An ecvt is virtually the same, only using electric motors instead of hydraulics.
In short, by allowing the "loaded" path of energy to be primarily transferred via the mechanical portion of the transmission, it cuts the losses associated with transferring power hydraulically. My question is, what maintains the integrity of the hydraulic circuit when the unit is in full lock, or full speed? Half of the output torque load is being converted to hydraulic pressure with zero flow in the system... so how are they managing these pressures and the inherent temperature rise without flow?
You said it yourself, it's just a constant pressure with no flow, you're not putting any energy at all into the hydraulic system when there isn't any flow to generate heat or increased pressure.
Doesn't matter what pressure you're at if nothing is moving you are completely inert and no power (thus no heat) is being transmitted.
As an aside the hydrostat's operating pressure is roughly 500 bar if I remember correctly.
Ese sistema hidraulico de cvt e bem.interecante e parece ser bem.duravel alem de nao.muito complexo e manutencao.mais facil ...parabens
@Music201ful You mean the Steyr transmission?
"Fendt launched the revolutionary Fendt 926 vario in 1996. This was the first ever stepless transmission to be launched in the tractor market, and is patented to be the only ever truly stepless transmission, with brands in competition unable to make a transmission as advanced as a Fendt Vario."
Can you explain what's going on with the hydraulic pumps physically pivoting side-to-side? I don't understand that part of the CVT's operation.
i believe it changes it's volume of oil per revolution. slid one way, low volume, slid the other way, high volume.
Which will change how much 'pressure' that ring gear will feel, (not because of load) and transmit power. It's still a gear connected engine-to-tire transmission.
How fast that ring gear rotates.. is controlled by the amount of oil being pumped. Think of having a 'locked' ring gear, or one turning as fast as the input... or infinite settings in between. They all have an effect on how fast the output shaft will turn.
@Music201ful This AGCO CVT is actually the Fendt Vario transmission which was the FIRST one on the market.
One question, does this transmission have any actions to change gear ratios like some other tractor cvts?
@@jacktackfly8838 It's a power split transmission with a planetary gear branching the power to Hydromotors/-pumps (Toyota uses a similar technology for their hybrids - electric instead of hydrostatic though). There are plenty of videos and websites that describe these transmissions.
@@MichaelLutz ye ik tnx, i just find it a bit weird that Case, class, new holland has a transmission with clucth packs and vario transmissions have no clutches and gear shifting
@@jacktackfly8838 Fendt improved the efficiency of the hydro motor/pump. I guess they had a patent so competitors couldn't copy it. The key was to increase the swing angle from 30° to 45°. Fendt's Vario transmission is apparently efficient enough to have only on range ("gear"). Originally (and maybe still most models) have 2 ranges. One for transport and one for field work.
@@MichaelLutz wow, so let me get this straight, fendts have 2 ranges so they have a shifting mechanism or do they just make those 2 ranges with hydraulics?
Good work air
I wonder how powerful that hydraulic pump and motor must be
I hauled 7000 gallon tanker on hills
it handles around 400 bars easy
In these configurations... typically less than 8% of of the engine's output, at most, is transmitted through the hydrostat. Under typical duty/load, especially in this application, it's usually less (3-5%). Agricultural applications don't have a huge amount of variation in RPM... and that's about all the hydrostat does, is serve as a speed regulator.
The Prius uses the same principle, except the motors are electric, not hydraulic.
Well, if you and 99,999 other people are willing to shell out $100, i'll gladly develop and incorporate this type of IVT as an optional transmission in my forthcoming GT car.
@Rpleech1 If you look at the video the you can see the pump and/or motor swing from middle to the left or right. What this has to do about changing the transmition speed from the gear to the pump or from the motor to the gear is not clear to me. For clarity I've got it about the oil-driven motor.
is this from the fendt vario trasnmission?
Yes
Not the same, the IH was fully hydrostatic, ie. variable pump driving a variable motor with no mechanical connection.
What does 'swings left/right' actually accomplish? How is the rotation affected?
Gene Koveski It uses swash-plate type hydraulic pumps and motors. With this design, the pistons on the pump/motor are connected to the swash plate. "Swinging the pump" means "Tilting the swash plate". This adjusts the amount of volume change in the pump or motor per revolution, and, hence, its oil consumption and resistance. If you Google "Variable displacement hydraulic pump" there are some pretty good explanations. Hope this helps!
Ahhhh. Okay. Now it kind of makes sense.
It think it needs a new name as cvt has so bad rep from cars. Great looking system.
that's why they call it fendt vario and not fendt cvt
Well as a farmer, i don't give two fucks about a tractor part having a name used on a shitty car
Will this work on engines with 135 HP ?
(Agco) Fendt has a 415 hp tractor
Or smaller ones too
The range at the moment is 70 hp ro 600 hp
They gears are not showing the correct direction. If you watch the input shaft compared to the directions of the pump and motor gears it would be shredding the splines of the gears. I feel sorry for the fella who didn't catch that. If you're going to make a training video showing how a system works, atleast make it to function properly.
I think it was possible to replace the hydrolic pump and motor with torque converter?
work with you
Final CVT SRS-LS4S B6 (LS5000)- SUPER TRANSMISSION MADE IN RUSSIA
@Music201ful Well enlighten me then. I believe Case had nothing of this kind. MAYBE Steyr but at that time it wasn't part of Case.
Is this any good?
According to our customers(sweden) it´s the best transmission on the market, we have a lot of happy fendt-drivers. If you´re gonna change it tough, it will cost around 8-10k(depending on modell) euro plus work for an exchange transmission. Many will fail around ~3500-5000h of work, but many will last longer(some rare cases shorter), depending of conditions of course.
Overall they´re very reliable!
Not AGCO - this stepless drive is created by Fendt(Fendt Vario) in 1996!
And agco bought fendt in 1997
i don't think that this device will results in an infinitely variable torque since the gear ratio is fixed between input and output shaft in all conditions>> it should be in a way that torque and speed is adapted with the load on the output shaft
pressure/speed differential....
well this one equals, or surpasses ordinary mechanical transmissions as effiecency goes. I aint hot, or loud either..
So basically its a fancy hydrostatic unit!
A very fancy one yeah. Just as simple to drive as a hydrostat but much more efficient to the point where it stands up quite well versus a powershift in efficiency.
Just like sisu engines are now agco power
Post please
I now Agco bought Fendt etc, by why call it Agco's CVT? I mean it is a product that Fendt created, so at least call it the Fendt CVT. Just give the people the credit they deserver, not get some with buying a company :)
First, Fendt isn't a person, it's a corporation, a legal fiction. Second, following your logic every pushrod overhead valve engine would be a Buick and every double overhead cam four valve engine would be a Peugeot and every SUV would be a Jeep.
its like peugeot buying talbot for its rally development team and "suddenly" coming up with the legendary 205 GTi. and the group B version. FUCK mergers.
@@nonyadamnbusiness9887 the steam locomotive/ car Richard trevithick. People who are alive want credit for the shit they did, not being shoved around by corperate non disclosure agreements. on stuff they made happen
@@rat_king- While I agree that corporate entities are WAY too powerful...the only way to change that is EVERYONE STOP using money to tool the next guy!!!
It's used in Massey's as "dynashift" and challengers as something else. Possibly valtra aswell
Hydrostatic removes all the gears!
Lower pump gear never reversed.
PAY ATTENTION
International got there first, about 50 years ago...hot, nosy and inefficient...
Hello
it's called a hydrostatic transmission.
Hydrostatic uses only hydraulics
No it’s not
very complicated exploination. I don't get it after 3 times seeing the movie...
@Hano Herb No, it is complicated...many things do not explain here. CVT are always complicated to design.
Looked QUITE simply a pressure/speed differential
First you must learn how a variable displacement hydraulic piston pump works. Then it will mak sense.
OMG a Planetary gear set controlled by Fluid slip?
So.... its a torque converter and Planetary Gear set.
with the torque converter connected the ring gear and the engine connected to the torque converter and the sun gear.
ALL you have done here. is add needless complexity to a simple as HELL system. what is wrong with you?
SO pray tell which part is unnecessary???? I wont naysay the engineers...
@@charlesangell_bulmtl Trade the fluid pumps for the impeller and the turbine in a torque converter.
Remove the 3 un- necessary shafts, and you have: a torque converter where one gear is attached to the sun and the other to the planet carrier.
The torque converter controls two parts of the planetary gearbox, the sun and the planet carrier, the ring gear being output. As torque demand increases, the difference between the two halves of the torque converter gives you the different gear ratios. The torque converter is "seeking" direct (straight through) drive
The only slight advantage i can see is the Lack of slip in the system, using pressure difference rather than velocity difference in this system. See use of a positive displacement pump (hydraulic gear pump) vs a impeller/ turbine.
Anything that slips is converting energy to heat, ie wasted fuel.
More things to break more things to fail, more things to exercise your money's thermal properties
@@rat_king- Thank you-Your answer will require me a bit of processing as the video gave me an easier digest ...Pray tell, do you know of a video with what you describe?
@@rat_king- Thank you , I subscribed to you I hope you don't mind...
From my 20s, a book on carburetor patents, being the impetus, this peckerhead/wood(me) has been on a slight crusade to sidestep the screwing we receive from the powers that be..
..latest searches include regen. hydraulic powertrains.
Downside...cost of accumulator tanks, need to build, F**k their prices.
CVT has been an attractive thought but for the losses and complexity...and $$$.
Seems that CZcams may be good for more than just killing time LOL.
I like your title, I think of myself as an Amerikaner Scweinhundt...Sgt. Rock reference. I think it fits nicely as I'm primarily of German descent.
Would like to build a simple 5hp reverse trike with regen. hydraulic powertrain....