1. Attachments are working again! Check out this thread for more details and to report any other bugs.

3rd Gen Hybrid eCVT Transaxle in the Classroom

Discussion in 'Gen 3 Prius Technical Discussion' started by cycledrum, Jan 25, 2013.

  1. cycledrum

    cycledrum PSOCSOASP

    Joined:
    Apr 9, 2008
    8,245
    1,202
    0
    Location:
    NorCal
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    Get a good look at the 3rd Gen MG1, MG2, clutch plate and power split gears on the bench and explained by an automotive professor. 3rd Gen Prius has motor speed reduction planetary gearset not used in 2nd gen, allowing higher speed for MG2 and 2.5 to 1 torque multiplication for more powerful electric drive and higher EV speed. This design was also used in 2006 HiHy and 2007 CamHy.

    Enjoy!

     
  2. pichner

    pichner Metallic Maniac #001

    Joined:
    Nov 30, 2012
    66
    20
    0
    Location:
    Minneapolis, MN
    Vehicle:
    2012 Prius
    Model:
    Three
    I have watched this bad boy a few times, great info!
     
  3. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Why has the gen3 version flywheel got a ring gear.
     
  4. pichner

    pichner Metallic Maniac #001

    Joined:
    Nov 30, 2012
    66
    20
    0
    Location:
    Minneapolis, MN
    Vehicle:
    2012 Prius
    Model:
    Three
    They had to make that crazy speed reduction "thing" to allow the electric motor to operate at higher wheel speeds. At least I think that is what you are asking about.
     
  5. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    No. If you look in the beginning the gen2 flywheel that has the torque limiter clutch in the middle has no ring gear obviously because the Prius does not have a normal starter motor. Then look at the gen3 flywheel and it has a normal strait cut ring gear on it (not mentioned in the demonstration).
     
  6. tumbleweed

    tumbleweed Senior Member

    Joined:
    Oct 3, 2005
    4,067
    687
    0
    Location:
    Eastern Oregon
    Vehicle:
    2010 Prius
    Model:
    V
    Good question, could it be they use the same flywheel as the non-hybrid vehicles that share that engine?
     
  7. Sabby

    Sabby Active Member

    Joined:
    Sep 17, 2011
    295
    127
    0
    Location:
    SoCal
    Vehicle:
    2015 Prius
    Model:
    Two
    Thanks for sharing. Finally explains how the plug in can hit 61 mph without the gas engine on, compared with 46 mph for the Gen III without overspeed on MG 1.
     
  8. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,910
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    That was my first thought but that would also apply to the gen2 version. Toyota would not do this however. Just think cost of making and fitting ring gear (heated and shrunk on) say £10-$16 at factory prices, on 1 million cars or more since gen3 start of production = £10,000,000- $16,000,000 they do not through that sort of money away.

    John (Britprius)
     
  9. jadziasman

    jadziasman Prius owner emeritus

    Joined:
    Jan 17, 2011
    1,355
    486
    0
    Location:
    District 6
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    That's just great. Thirty minutes of youtube footage and I'm no longer happy with my Gen II and its antiquated technology. Toyota just had to add a second planetary gear set to the eCVT to transform my Gen II into a Model A. Sigh.

    But thanks much for the vid, cycledrum. I have the Gen II eCVT teardown/demo from the same folks in my video archives.

    Now it's time for me to find a >100K mile Gen III for under $10K. Let the search begin!
     
  10. El Dobro

    El Dobro A Member

    Joined:
    Jul 12, 2011
    6,972
    3,209
    1
    Location:
    NJ
    Vehicle:
    Other Electric Vehicle
    Model:
    N/A
    It could just be a flywheel that was lying around the shop and used for the demo.
     
  11. xs650

    xs650 Senior Member

    Joined:
    Jul 2, 2010
    4,539
    1,433
    9
    Location:
    Northern California
    Vehicle:
    2010 Prius
    Model:
    II
    Nice observation! For what it's worth, the factory repair manual has several illustration that show the Gen III flywheel in line drawing format. No teeth show in any of them. That's not conclusive because maybe they just didn't feel like drawing the teeth :D . Possibly the flywheel in the picture wasn't from a Prius?
     
  12. cycledrum

    cycledrum PSOCSOASP

    Joined:
    Apr 9, 2008
    8,245
    1,202
    0
    Location:
    NorCal
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    He mentioned that 3rd Gen transaxle was a P310 from a 2008 Highlander or Lexus RX hybrid. Sounds like 2nd Gen transaxle was only used in Prius.

    Sorry if this video spurs one to sell off their 2nd gen :eek:
     
    xs650 likes this.
  13. jadziasman

    jadziasman Prius owner emeritus

    Joined:
    Jan 17, 2011
    1,355
    486
    0
    Location:
    District 6
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I was just being sarcastic, which is difficult for me to express with text and I'm not sure which emoticon works for that.

    I always wondered how the Gen III Prius could achieve better mpg than the Gen II with a larger ICE. Now I know.
     
  14. telmo744

    telmo744 HSD fanatic

    Joined:
    Apr 8, 2010
    2,168
    764
    0
    Location:
    Portugal
    Vehicle:
    2010 Prius
    Model:
    N/A
    Larger ICE usuallty lowers BSFC, and Toyota confirmed that when launched GenIII. Transaxle improvements are also to be taken in account but may not be as determinant.
     
  15. szgabor

    szgabor Active Member

    Joined:
    Jul 29, 2009
    993
    175
    0
    Location:
    Oceanside NY
    Vehicle:
    2012 Prius
    Model:
    Two

    not sure if this is my pc or something but the sound is awfull for me many places can not understand the words from the noise ... is this just me ???

    other youtube stuff works though
     
  16. tumbleweed

    tumbleweed Senior Member

    Joined:
    Oct 3, 2005
    4,067
    687
    0
    Location:
    Eastern Oregon
    Vehicle:
    2010 Prius
    Model:
    V
    I just tried it again and it looks and sounds OK on my computer. I think it uses Adobe Flash Player, try downloading the latest version.

    YouTube videos won't play? - YouTube Help
     
  17. szgabor

    szgabor Active Member

    Joined:
    Jul 29, 2009
    993
    175
    0
    Location:
    Oceanside NY
    Vehicle:
    2012 Prius
    Model:
    Two

    Thanks ..

    What solved the problem for me, is to download the video completely and then watch it ... that way it was fine. Not sure why I had problem with streaming.

    And it worth the wait... I had an idea how this works but really seeing the parts "outside" was amazing. It would be even better if the video would show where and how all these sit in the car. Like when it it taken out.
     
  18. Madduck

    Madduck New Member

    Joined:
    Jun 16, 2013
    22
    4
    0
    Location:
    SLC, Utah
    Vehicle:
    2010 Prius
    Model:
    II
    Does anyone else wonder what this guy looks like? Probably just like my auto shop teacher in high school.
     
  19. Feri

    Feri Active Member

    Joined:
    Jun 25, 2011
    761
    144
    0
    Location:
    Maldon Victoria Australia
    Vehicle:
    2010 Prius
    Model:
    III

    I'm no expert but isn't this because Gen II used a chain for power transfer and Gen III uses gear to gear?

    Sorry hadn't seen the video when I wrote above.
     
  20. Madduck

    Madduck New Member

    Joined:
    Jun 16, 2013
    22
    4
    0
    Location:
    SLC, Utah
    Vehicle:
    2010 Prius
    Model:
    II

    This video shows a stylized location of the transaxle in the car. The video is of a Lexus but it is the same design.