Power Split Device

Discussion in 'Gen 4 Prius Technical Discussion' started by dstahre, Jun 27, 2016.

  1. Jeff N

    Jeff N The answer is 0042

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    How am I moving the goal post? Inflation exists.

    John originally quoted a GM exec from 2007, 10 years ago, saying the Volt would be less than $30,000. It's just the truth that $30,000 in 2007 is now equivalent to almost $35,000 in 2017 dollars and a new Volt now costs less than that.

    John is the one who really moved the goal posts and that's fine. I have no problem with that. His magic $30,000 price tag limit was equivalent to about $25,920 in 2007 dollars.
     
    #81 Jeff N, Feb 3, 2017
    Last edited: Feb 3, 2017
  2. bhtooefr

    bhtooefr Senior Member

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    To be fair, start the inflation in 2010, as the target price was as of the target launch date of 2010.
     
  3. alanclarkeau

    alanclarkeau Senior Member

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    Car prices have remained remarkably static over the last couple of decades - it's the equipment which has changed.

    In 1992, our CAMRY was $22500, a Corolla was less than $20,000.

    By 1995, we bought a Corolla sized MAZDA 323 (you might have called it a FAMILIA?) for $22,000. So it had increased 10%.

    In 2001, I looked at a Mazda 3/Ford Focus - $22,000 still - but with quite a bit more equipment, airbags, ABS, Electric front windows etc.

    2008 - Ford Focus/Mazda 3 - still $22,000 - but with stability control, 4 airbags, all electric windows.

    2016 - Ford Focus/Mazda 3 - still $22,000 - better fuel efficiency, bigger, now alloy wheels, 6 airbags, more goodies.

    The other thing is that size has crept a little bigger, though, the 1995 MAZDA 323 sedan was quite big inside, and the back seat was better for children than today's Mazda 3 which is claustrophobic for small people with high sills, small windows and wide pillars - for crash strength.

    Crash-wise, there is no comparison - astronomically improved (photo from TopGear F/B page).

    upload_2017-2-4_12-36-13.png
     
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  4. Jeff N

    Jeff N The answer is 0042

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    Seems reasonable. That would be $33,020 then.
     
  5. john1701a

    john1701a Prius Guru

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    That's why PRICE POINTS exist. You can't just pick the economic factors you like and disregard the ones you don't.

    An automaker targets a vehicle for that, than makes adjustments as the years past to retain that positioning. Yes, we've seen a gradual climb over the decades, but being that far off target has proven a barrier to mass acceptance. In fact, that is the very reason why the subsidy exists, to temporarily counter pricing while those adjustments are being made... and time is quickly running out.
     
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  6. Prodigyplace

    Prodigyplace Senior Member

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    Raises hand
    There are many posts from those of us who have the Ecopia EP422 Plus tires. Mine are the Japanese made ones.
     
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  7. Jeff N

    Jeff N The answer is 0042

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    I guess I assume that "price points" are relative to the actual value of the currency at a specific point in time.

    Fifty years ago basic middle-class cars had a starting competitive price point of maybe around $2,300 -- the price of a Ford Fairlane sedan back then. Obviously that's no longer the case. According the Labor Dept., $2,300 in 1967 is equivalent to about $16,500 today. The cheapest small cars of that time like a 1967 VW Beetle started at around $1,650 ($11,850 today). A modern equivalent might be a Nissan Versa S at $12,850.

    I would think the same concept applies to price points from more recent history.

    The subsidy exists to bootstrap the market by offsetting the price of the battery pack to pull forward the time in which cars with larger rechargeable packs could be brought to market. Automotive battery prices have been plunging as intended as they have become more of a commodity rather than a research topic.

    Certainly plugin cars will have to find customers at non-subsidized prices at some point (perhaps soon). I think recent history has shown that there is a market demand for cars with longer battery ranges and performance and that includes the willingness to pay more for improvements in those attributes. In the long run, plugin cars have to continue coming down in price but that can't be done instantly and is therefore an ongoing process where today's sales finance R&D and volume scaling that further drives down prices.

    When subsidies are removed that will clearly remove some market demand but I think the overall demand for vehicles with stronger electrification specs will continue and I think the plugin market is now primed for continued growth, even without further subsidies (albeit slower growth).

    Recent history has clearly demonstrated that plugin market success is not entirely driven by low pricing.
     
  8. RCO

    RCO Senior Member

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    I suspect you are just pretending to be dumb, but I'll play along.

    Let's say you predicted going to Mars x number of years ago. That's your goal, OK?
    Then inflation comes along all unexpected, the way it always does and suddenly it 2017 and you didn't get to Mars, but you did manage to fund a moon landing. Yes, you met a target, but not your original goal, so if you claim to have met your goal you will have had to move your goalposts from Mars to the moon.

    Now, let's plan our escape from from wonderland and get back to reality, shall we.(y)
     
  9. Jeff N

    Jeff N The answer is 0042

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    John was quoting a goal announced in 2007 for a car going on the market at the end of 2010. The relevant point in time is, therefore, 2010-2011, not 2017.

    John's own personal price point is $30,000 regardless of what recent year we are discussing or how the value of the dollar has changed or how wages and income have changed or how the general price of cars and other consumer products have changed.

    That's fine. As I've said all along, I was challenging not his own fixed numerical price point but the way he was ignoring inflation in the dollar price quote that he referenced from that GM exec and the context in which it was originally stated by Bob Lutz.
     
    #89 Jeff N, Feb 4, 2017
    Last edited: Feb 4, 2017
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  10. PeterHaas

    PeterHaas Member

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    I presently own a 2014 Prius c, a 2012 Prius hatchback, a 2001 Prius sedan ... named in order of purchase ... and, now, also a 2008 Ford Escape Hybrid 4x4 SUV. It is my strong preference, given adverse road conditions present this winter, to favor the 2008 Ford Escape, with the 2012 Prius hatchback as a very worthy second choice when in dry weather.

    The purpose of this post is to indicate the differences (and similarities) between the Prius HSD system and the Ford Escape Hybrid system. There are actually more similarities than their are differences, as Aisin Seiki Kabushiki Kaisha (Aisin Corporation) actually developed the HSD as it is a Toyota Group company, and is 50 percent, give-or-take, owned by Toyota Corporation.

    The Prius HSD has gone through four revisions, Gen 1, Gen 2, Gen 3 and, now as of 2016, Gen4. How do these differ from the offerings of Aisin Corporation.

    Well, the Aisin Corporation Gen 1 and Gen 2 (as used on the Ford Escape Hybrids) and the Gen 3 (as used on the Chrysler Pacifica Hybrid) are actually quite the same as the 2016 Prius.

    That is, the the Toyota Gen 3 product actually adopted the hybrid system design which Aisin Corporation had been marketing to others (Ford and Chrysler) all along, when coming up with its Gen 4.

    How are these different?

    The Aisin products implicitly incorporate a power-split device (which Aisin apparently developed some years ago, and was immediately adopted by Toyota). This is absolutely necessary for integrating the ICE, the MG1 and the MG2. But the specifics are quite different thereafter.

    All the Toyota Gen 1 through Gen 3 HSDs are "single axis" designs, and the Gen 4 HSD is "two axis". The Aisin Gen 1, Gen 2 and Gen 3 systems were all "two axis" all along.

    Why is this significant.

    Well, it means that the Aisin products implicitly incorporated the "motor speed reduction device" from the very beginning of their products, whereas Toyota had to wait until its Gen 3 in order to incorporate this device, and which optimizes the use of the MG2, and reduces the impact on the MG1.

    Also, the Aisin products, being "two axis" from the very beginning, always incorporated a much narrower width hybrid system, thereby saving considerable engine room space.

    Much has been made of Ford licensing certain Toyota (really Aisin) technology in return for certain Ford technology.

    However, the Ford Escape Hybrid only incorporates the Aisin eCVT ... the remainder of the vehicle (the Atkinson Cycle ICE, the high-voltage battery, and the various control systems) are entirely Ford's.

    Is this a "Toyota type" hybrid. Sure it is. And it behaves like a Toyota/Prius ... within reason.

    Heck, it even uses the same "primitive" Immobilizer system for its ignition key ... not unlike that in the 2001 Prius.
     
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  11. bhtooefr

    bhtooefr Senior Member

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    My understanding was that Ford contracted the manufacture of the hybrid system that they designed to Aisin, though - in fact, I wouldn't be surprised if they did it partially to satisfy the patent dispute.

    In any case, the Ford HF-35 used in the current Fusion and C-Max hybrids and Energis is Ford-built, but the same 2-axis design as the Aisin HD-10 (from the first-gen Escape Hybrid) and HD-20 (from the second-gen Escape Hybrid and first-gen Fusion Hybrid).

    The Gen 4 Prius's P610 does have a simplification from the HD-10/HD-20/HF-35 design, though - in those gearboxes, the power split device ring gear and the MG2 reduction gear are geared to separate gears on the same output shaft, whereas they're geared to the same gear on the P610. Saves weight, cost, and a small amount of space, at the expense of some gearing flexibility.

    Also, is there a citation for the Pacifica's Si-EVT being produced by Aisin? FCA claims that they developed it and manufacture it themselves: Minivan Monday: Award-winning propulsion system powers all-new Chrysler Pacifica Hybrid | FCA North America Corporate Blog
     
  12. PeterHaas

    PeterHaas Member

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    The Weber College site states that the Pacifica eCVT is the third generation Aisin CVT (HD-30).

    The same site states that 2008 and later Ford Escape Hybrids were Aisin CVT (HD-20) and the pre-2008 Ford Escape Hybrids were Aisin CVT (HD10).

    I have examined the videos explaining the HD-10/HD-20/HD-30 similarities and differences, and it appears that the only differences are eCVT size (mainly width), and that the axes of the main shafts all lineup, so the internals are actually much the same.

    Ford, in my book, is to be commended for providing a newer technology hybrid battery, one which at 250,000 miles of rugged taxicab service in New York City, upon physical examination proved to have at least 80 percent of its useful lifetime remaining. And, the Ford Hybrid battery resides wholly underneath of the cargo area, thereby maximizing the cargo area for use by the owner. Toyota chose a different format Hybrid battery, one which consumes significant room.

    Mind you, this is not intended as a "knock" on the Prius, as its role is well-defined as the ultimate Hybrid sedan, whereas the Ford is somewhat less-defined as a 4x4 SUV and as a 4x2 taxicab.

    But, I live in an area where a 4x4 SUV is almost mandatory for use in inclement weather, yet a sedan is perfectly acceptable in dry weather.

    Which is why I own and drive both vehicle types.

    As a Toyota-centric person, it would have been natural for me to wait for the availability of the 2017 Toyota RAV-4 Hybrid (at $35,000, I might add), but I was able to obtain a low-mileage 2008 Ford Escape Hybrid with every possible accessory for $6,500. Quite a difference!

    I might add that my Ford Escape 4x4 SUV cannot compete with my 2012 Prius hatchback ... and I never expected it to do so ... and perhaps the Ford 4x2 SUV could have had a better record vis a vis the 2012 Prius hatchback, but I needed a 4x4, and the 2017 Rav-4 Hybrid was unavailable or was in very short supply.

    Whatever the reality, one does what one has to do, and I presently own four Hybrids, named above.

    My 2002 Hyundai Santa Fe 4x4 cannot possibly achieve more than 17 MPG on a consistent basis, yet my 4x4 Ford Escape Hybrid almost always achieves nearly 30 MPG.

    What do I choose to drive: why the 2008 Ford Escape Hybrid 4x4 in today's inclement weather, or my 2012 Toyota Prius hatchback in tomorrow's fine weather.

    It is always nice to have options.
     
    #92 PeterHaas, Feb 15, 2017
    Last edited: Feb 15, 2017
  13. PeterHaas

    PeterHaas Member

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  14. That_Prius_Car

    That_Prius_Car Austin Kinser

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    My Gen.IV's is 74 mph.
     
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  15. PeterHaas

    PeterHaas Member

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    An impressive YouTube video was the disassembly of the NYC taxicab after 250,000 miles ... specifically the disassembly of the Aisin eVCVT, but the disassembly of the hybrid battery was also informative.

    The eCVT was examined for wear in the power-split device. There was no measurable wear at 250,000 miles.

    The battery was partially disassembled (the main difference between Ford and Toyota is the Ford has selective/active cooling: should the outside air temperature be suitable, it is selected and brought in to cool the hybrid battery; should the outside air temperature be too hot, an air conditioner is selected and this unit cools the battery). There is ducting within the left inside trim panel of the vehicle to accommodate this. Whenever outside air is selected, it is first filtered using a user-replaceable air filter. Replacements cost under $8, delivered, on eBay. The battery air conditioner has piping to a condenser which is located up front. A more complicated solution, to be sure, but one which pays for itself in extra-long battery lifetime. The cells are similar to "D" cells, but are welded together into five cell units. I believe Sanyo makes the cells.

    The Aisin eCVT in the Ford uses a different oil from Toyota. A special Mercon formulation.

    My Escape is 4x4, and there are quite a few gearboxes, more than in a Prius, and each requires a different fluid specification.
     
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  16. Jeff N

    Jeff N The answer is 0042

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    Can you provide the web links?

    I see a WeberAuto YouTube video showing the 3 generations of hybrid transaxle used in Ford products:



    Neither this video or its description ever mention HD-30. He does mention attending an FCA briefing and noticing the similarity of design between the Chrysler Pacifica Hybrid transaxle and the Ford/Aisin design but he says on the video that:

    We've seen the FCA press release posted earlier in the thread by @bhtooefr which states that it is manufactured by FCA in the US and was designed by FCA in the US. FCA plainly states that it used a 6-speed Aisin conventional automatic transmission in several of its models and that it uses a ZF 9-speed automatic in other vehicles including the conventional Pacifica. So, it's not like they present that these 3rd party transmissions were all developed in-house by FCA. Why would they then deny Aisin's alleged development of their Pacifica hybrid transmission?

    A Wikipedia article mentions that:

    Aisin Seiki - Wikipedia
    However, this appears to have been added in the last two weeks by Peterh5322 without any citations to source references. Was this added by @PeterHaas?

    As best I can tell, Toyota engineered the original Prius transaxle system themselves. Various souces state that this original design, used in the 1st generation Prius, was manufactured by Aisin.

    Green Car Congress: Aisin Seiki To Boost Supply Of Motor Systems For Ford Hybrids
    Somehow or another, Aisin developed a similar transaxle in some collaboration with Volvo (beginning in 1997) and then Volvo was bought by Ford and this transaxle came to be the T-030 (Ford name?) or HD-10 (Aisin name) used in the 1st generation Ford Escape hybrid.

    Radical Innovation in a Small Firm: A Hybrid Electric Vehicle Development Project at Volvo Cars (PDF Download Available)

    Automotive News
    Other sources say that Aisin manufactures the transaxle used in the Camry hybrid (same as the Toyota Highlander, I think) but Toyota manufactures the 2nd and later Prius generation transaxles themselves. Aisin may also manufacture the new Lexus LC500h multi-stage transmission that combines an eCVT with a 4-speed automatic.

    The bottom line in all of this is that Toyota, Aisin, Ford, Chrysler, and even GM are all following roughly the same approach with hybrid power-split transmissions as discussed in this article that I wrote last year:

    Revenge of the Two-Mode Hybrid

    It does not mention Aisin by name but it also doesn't mention Volvo, or GM's development of the FWD variant of the RWD Two-Mode hybrid transmission which was ultimately cancelled but had much of its design recycled into the 1st generation Chevrolet Volt transaxle. I had to skip some details because it was already overly long.

    As that article notes, all of these designs are ultimately derived from a TRW design from around 1970 that was ahead of its time.

    Also, GM filed a patent in 1995 that described the actual specific architectural design of the eventual 1st Prius hybrid transaxle as Toyota was just in the first stages of designing it. The same patent described using a reduction gear between MG2 and the output shaft long before that was realized in the first Ford/Aisin transaxle, the Highlander/Camry transaxle, or the 3rd generation Prius transaxle.
     
    #96 Jeff N, Feb 16, 2017
    Last edited: Feb 17, 2017
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  17. PeterHaas

    PeterHaas Member

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    The Weber College YouTube specifically mentions the HD10 and HD20 in the Ford Escape context and the HD30 in the Chrysler Pacifica context.

    In his video, he lines-up all three and shows that they all have the same geometry, although their gear ratios are somewhat different.

    In these designs, the central combining gear drives the differential. The output of the power-split device and the MG2 meet on either side of the central combining gear.

    The size of the teeth are different as the power to be transmitted is different.

    Early Prius always used straight-cut spur gears. The Aisin eCVTs used angular cut helical gears (which Toyota adopted in its Gen 4 HSD).

    The in-line automatic transmission-like HSD used in the large Lexus hybrids is also Aisin, and Aisin's web site shows this transmission.
     
  18. Jeff N

    Jeff N The answer is 0042

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    Please correct me if I'm wrong, but I don't think that video or its description ever mentions "HD-30" or "T-032" and he says he doesn't know who manufactures the Chrysler Pacifica hybrid transaxle but that the drawings of it that he saw at a Chrysler/FCA training session looked "similar".

    What are the web links to the videos or other materials that mention HD-30 or T-032?
     
  19. Jeff N

    Jeff N The answer is 0042

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    He lines up the Aisin HD-10, Aisin HD-20, and Ford HF35. He does not mention an HD-30 or T-032.
     
  20. PeterHaas

    PeterHaas Member

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    After re-reviewing the YouTube, I agree with you: it is not an HD-30, but an HF-35.

    All are parallel in design.

    The HD-10 and HD-20 are clearly of Aisin origin.

    The differences are the HD-10 uses a 330 volt battery and has no internal boost circuit, whereas the HD-20 has an internal boost circuit, and a lower voltage battery, but the HD-20 is 8 inches ... give or take ... wider in order to accommodate the internal boost circuit.

    The HF-35 has no internal boost circuit, so its housing is more like an HD-10 in size, but it has an external boost circuit in a cubic box which undoubtedly exceeds the volume of that which was added to the HD-10 to make the HD-20, possibly by a factor of two.
     
    #100 PeterHaas, Feb 28, 2017
    Last edited: Mar 1, 2017
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