Is This The New PiP Transaxle?

Lexus Hybrid Drive had a two speed HSD with a clutch back in 2007 with GS450h.

This appears to be advancements on Gen3 Prius with two clutches added.

Here is the cleaned up version to reveal the elegant setup.

 

Just realized you wrote that article.

I think the use of clutch in Lexus Hybrid Drive should be mentioned. Otherwise, it would sound like Toyota is copying GM, especially coming from reading that title.

 

Don't know if this is the arrangement Toyota is planning for the next plug-in, but if yes - does this indicate that the next plug-in will not have Gen 4 body? (or at least not exactly the same?)

 

i thought the pics were a bit different?

if correct, what advantages might this gain for the next pip?

 

Per the leaked pictures, there was the green and blue one, exterior looks different enough but gotta be based on the same platform.

If this setup is used in PiP2, the transaxle may not be thin enough for the aux 12v battery to fit under the hood.

 

not a big deal, imo, but what advantage would it gain?

 

More or less cargo space. Better for PiP to have more room back there for bigger PHV pack and spare tire.

 

I am somewhat impaired at interpreting these mechanical designs . What is accomplished by hooking the secondary planet carrier to the primary planet carrier/ICE rather than having it locked to the transmission case? It would seem to only make a difference if the ICE were turning. TIA for any enlightenment.

 

OK. I see. Normally, if MG1 is powered, it is going to act as a starter for the ICE, or alternatively it could be turning the ICE without fuel to moderate MG1 speed or get compression braking. But if the planetary gears are connected together and grounded (locked to the transmission case), then the power from MG1 can only go out the ring gear toward the wheels. Thus, MG1 can contribute to accelerating the car, rather than requiring the ICE to kick in to help. Addressing the common PIP complaint "I stepped on the gas pedal too hard and the #^%@ ICE started". Will MG1 really be more powerful than the ICE?

In the second scenario, the planetary gears are connected together, but not grounded, and the ICE turns. You say that this results in mechanical energy being routed back to the first gear set, specifically to the ICE. Why would one want to do that? Really asking the same question in the context of the Gen III transaxle, when would one want to electrically send energy back to the first gear set?

 

That what I meant when saying possible body different from Gen 4 regular. Wider transaxle, possible larger motors and electronics, larger traction battery, place for 12V battery etc. may dictate different body to accommodate.

 

I'm becoming uncomfortable with the term elegant design. The Gen 2 was truly remarkable with what it could achieve with only one planatery gear. Whilst I'm all for the advancement of technology, multiple gearsets and multiple clutches brings us rapidly closer to the un-elgant auto gearboxes of the past.

 

It is more complicated and has clutches.
Maybe Toyota filed the patent to be used on future Lexus plug-in? Other non Prius one?
It seems to me it will fit best cars that prioritize EV driving (speed and power demand) over efficiency, not Prius philosophy - but maybe I am wrong.

 

Perhaps they plan to use smaller ICE with PiP2. That's a possibility to keep the 12v under the hood but we'll have to see.

Larger motors may not be needed as it can combine the output of both MG1 and MG2.

Your Prius v wagon also has two planetary gearsets. Really, only two clutches are addition.