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What is an eCVT? How does it work? Here is the answer

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Here is an excellent explanation about how the powersplit device in a hybrid works. The difference between the FFH & Fusion Energi is that the MG1 is larger in the Energi which allows it to reach a higher speed in EV mode (85 MPH vs 62 MPH). This is exactly how our cars work, the difference being that the gear ratio is different because of different size MG1, MG2 and engine.

 

Toyota and Ford both use this design for their hybrids and this technology is why the Ford & Toyota hybrids are superior to hybrids made by Honda, Kia, Hyundai, Volkswagen or GM. All the other manufacturers place an electric motor sandwiched between the engine and the automatic transmission. That is a less efficient design than what Ford & Toyota have done. The other hybrids are "one motor" hybrids, whereas the Ford & Toyota hybrids are "two motor" hybrids as they have 2 electric motor/generators as shown in the video. The next gen Honda Accord Hybrid and Plug-in Hybrid introduces a two motor hybrid system for Honda, their first. It will be interesting to see if it is engineered the same as I believe Toyota and Ford own the patents for this design.

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Watched this video while I was waiting on my car delivery last month. Very informative.

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Here is an excellent explanation about how the powersplit device in a hybrid works. The difference between the FFH & Fusion Energi is that the MG1 is larger in the Energi which allows it to reach a higher speed in EV mode (85 MPH vs 62 MPH). This is exactly how our cars work, the difference being that the gear ratio is different because of different size MG1, MG2 and engine.

 

Toyota and Ford both use this design for their hybrids and this technology is why the Ford & Toyota hybrids are superior to hybrids made by Honda, Kia, Hyundai, Volkswagen or GM. All the other manufacturers place an electric motor sandwiched between the engine and the automatic transmission. That is a less efficient design than what Ford & Toyota have done. The other hybrids are "one motor" hybrids, whereas the Ford & Toyota hybrids are "two motor" hybrids as they have 2 electric motor/generators as shown in the video. The next gen Honda Accord Hybrid and Plug-in Hybrid introduces a two motor hybrid system for Honda, their first. It will be interesting to see if it is engineered the same as I believe Toyota and Ford own the patents for this design.

 

 

Hybridbear you are a plethora of hybrid knowledge and information and I have learned a lot from your posts!!!! Thanks for sharing this!

Edited by gadgetguy

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I found a video that's noted as 3rd gen Toyota eCVT and published late 2012. Do you think that for might have updated the system the same way?

 

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Really simplified compared to a 6 speed automatic transmission. Also explains the clutch someone else mentioned in another thread.

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Really simplified compared to a 6 speed automatic transmission. Also explains the clutch someone else mentioned in another thread.

Hopefully that equates to longevity!

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I've watched the video, and what I take from it is that Toyota's original hybrid drive in the Prius involved one planetary gearset and then a roller chain, while the latest (the 3rd gen. illustrated above) incorporates two planetary gearsets to do the job....and with this system, there is no other transmission. So basically I'm confused. Since the planetary gear drives act in lieu of an actual transmission (IIRC), how does this amount to a CVT of any kind? It's a clearly different system than all the other CVTs shown in videos on YT, which incorporate two variable sheaves with a chain riding on them.....vary the sheaves, vary the drive ratio. On the Prius, thanks to its design, there isn't any need to have gear changes or variable ratios of any kind. Can someone elucidate, please?

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continuously variable transmission. No matter what is between the driving force and the output shaft, the end result is the same. The planetary gears do the job to the same effect as the sheaves, The Main reason for the gears is it makes a much more robust and stable transmission, less likely to wear, and can take more power input. Added benefit of the CVT, no clutches to wear out, no valve body to clog, and no torque converter to blow out. So in theory, as long as its kept cool and lubed, it will last far longer than any other transmission. The only time a planetary gearset has failed is either due to poor material quality, damaged due to something else failing and contaminating the lube, or over powering it. So the only thing that could potentially cause a failure is poor material quality.

 

I would love to tear one apart to see how it all works in hand rather than a video of the internals.

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continuously variable transmission. No matter what is between the driving force and the output shaft, the end result is the same. The planetary gears do the job to the same effect as the sheaves, The Main reason for the gears is it makes a much more robust and stable transmission, less likely to wear, and can take more power input. Added benefit of the CVT, no clutches to wear out, no valve body to clog, and no torque converter to blow out. So in theory, as long as its kept cool and lubed, it will last far longer than any other transmission. The only time a planetary gearset has failed is either due to poor material quality, damaged due to something else failing and contaminating the lube, or over powering it. So the only thing that could potentially cause a failure is poor material quality.

 

I would love to tear one apart to see how it all works in hand rather than a video of the internals.

Maybe when you get your HyTi you can take it apart then j/k!

 

I wonder how long before someone ends up with one that's totaled where maybe you could but it and see. There is a C-Max owner who had her C-Max totaled by a drunk driver while it was parked in front of her house on the street. It's so sad to think about that, I don't want to see any of these cars get totaled

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I found a video that's noted as 3rd gen Toyota eCVT and published late 2012. Do you think that for might have updated the system the same way?

 

I think that our hybrid system is like the 3rd Gen Prius shown in the video you found. After watching the video I think that based on the performance of our cars that this design is the actual design of our cars

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Here's "MrGreasybob" on YT tearing down a CVT out of a Ford 500. It appears as if at least part of it is based on planetary gearsets, as you can see. So....likely "hybridbear" is correct that there's a close relationship to the Toyota 3rd gen. driveline....or Ford licensed it, or something. Later on, though, he shows the two-sheave-connected-by-chain unit, which is more like the Nissan, Subaru, etc.

 

Edited by rico567

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The old Ford CVTs are not like the hybrid eCVT. Most transmissions have planetary gear sets but the ratio change in old CVTs is done mostly by varying the sheave diameters that the belt rides in. The Toyota / Ford eCVTs have no sheaves or belts and are essentially in one high gear all the time and the torque and power transfer is controlled by electronically varying the torque on MG1, the motor-generator on the center "Sun gear" of the planetary gear. MG1 routinely turns in either direction as a motor or a generator and is precisely controlled to make these transmissions the smoothest ever. There is also little wear. The Ford eCVT architecture is different from Toyota where the MGs are on the same axis. Fords' MG2, the traction and regen braking device, axis is parallel to MG1 and the eCVT and connected by a gear train. It's considerably bigger and designed for higher power.

Planetary gears are essentially two speed devices depending on what part is locked by bands or clutches. The eCVT is continuous because the "locking device", MG1 is not "on or off" but also anywhere in-between because of it's variable torque.

Edited by lolder

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@ lolder

 

Thanks for the additional info and differences on the Ford Hybrid power train.

I would be very interesting so see the same kinda video on a Ford system for all tech nerds on here. Maybe somebody can hook us up ;-))

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@ lolder

 

Thanks for the additional info and differences on the Ford Hybrid power train.

I would be very interesting so see the same kinda video on a Ford system for all tech nerds on here. Maybe somebody can hook us up ;-))

I totally agree corncobs and I to appreciate the extra info lolder. The whole system is very interesting and amazing how it performs so flawlessly!

 

Great car!

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I would second this.....I have not yet been able to locate a video that specifically shows the Ford eCVT in operation.

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Here's a Gen 1 Ford drive-train:http://alternativefuels.about.com/od/2008hybridvehicles/ig/2008-NY-Auto-Show---Hybrids/Ford-Hybrid-cutaway-motor.htm

A functional block diagram of Ford and Toyota would look the same. Here's a Gen 1 ( 2001-2003 ) Prius driving simulator. The values on the simulator would be different for different Ford and Toyota models but the principal is the same:http://www.wind.sannet.ne.jp/m_matsu/prius/ThsSimu/index_i18n.html?Language=en?Country=US

Check the box marked "Driving mode" and put it in "D range", slide the accel pointer to make it go.

Edited by lolder

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I would be very interesting so see the same kinda video on a Ford system for all tech nerds on here. Maybe somebody can hook us up ;-))

I requested that the same organization that produced the Toyota videos do a similar video for Ford. It appears that they are a college that trains mechanics and has a specialized hybrid program. I left a comment on their YouTube channel about that. It might be helpful if other users from here do the same. If they get a lot of requests about seeing the new Ford powertrain they will hopefully do it.

 

Click here to go to their YouTube channel and leave a comment requesting a Ford eCVT video explanation. Thanks!

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That is a great video. I saw earlier in parts diagrams that Ford has a clutch plate in their eCVT between the ICE and the planet carrier. This video confirms that Toyota has the same thing. It still appears that this clutch is passive (never released or locked) and just serves as a shock eliminator when the ICE starts and stops. At least the instructor never mentions the clutch playing a part in the power train. Anyone have another theory of the function of the clutch? The noise I have in my transmission "could" have a relationship to the clutch as it only happens when the ICE starts pulling or slacks off the load. I am learning to ignore the sound as it does not seem to be getting any louder. Yes, it would be great if we had a video of the Ford setup.

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if the ecvt of new ffh13 is anywhere close to the 2010 then the MG1 and MG2 won't be on the same shaft like the competition. check out this video shows how the 2010 one looks. ignore the d'bag reporter.

 

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Sorry the link didn't come through the first time.

Thanks for the video. This is why I wish someone would show us the inside of the new FFH design, to end the uncertainty.

Edited by hybridbear

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