Can Anyone Explain How the Hybrid CVT Works

[rivermaverick]

Ford marketing should have never used the “CVT” letters, even with the e in front, when describing this transmission because of all the baggage associated with those rubber band belt belt drive things. It creates too much confusion.

The eCVT is so different and so much better than those belt drive CVTs it really deserved a more differentiated name.

Agreed, when I saw 'CVT' I was thinking belt drive and was actually looking forward to driving a modern CVT - the last time I drove cars with a CVT transmission was in the '60s (DAFs).

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[scotty]

When I saw that the 2.5L had a 'CVT' I was expecting the 'conventual' chain belt, variable pully system. Turns out the HF45 is nothing like that! It looks very simple mechanically, 2 Motor/Generator Units (MGUs) one planetary gear set and some constant mesh gears, no sliding parts or clutches. the only mechanical bit looks to be the parking pawl. It must have some very clever electronics controlling it all.
Variable transmission seems a bit of a misnomer, the gear ratios are fixed, I've seen it described as a 'power split device' which may be a bit more accurate.
My understanding is that the anulus of the planetary gear set is connected directly to the wheels via the main traction MGU which only works as a generator when braking.
The planet carrier is connected directly the the engine and the sun gear is connected to the smaller MGU which is mainly a generator to charge the battery's, it only works a a motor to start the engine.
It is easy to see how the MGU starts the engine when the vehicle and the gear set anulus are stationary but how does it do it when the vehicle is moving, the anulus, planet gears and sun gear are all spinning, I'm guessing the small MGU applies an electrical 'brake' to the sun gear causing the planet carrier to turn and start the engine. Are there situations when the engine has to start when reversing?
BTW will the Maverick go as fast in reverse as forward (useful for avoiding terrorist road blocks, the 'reverse spin' maneuver doesn't work with ABS equipped vehicles, I've tried it!).
Sorry if my train-of-thought piece is cluttering the forum.

Are the two motors within the tranny covered under the warranty since they do other jobs then propel the hybrid, i.e. starter generator, alternator?

 

[rivermaverick]

Are the two motors within the tranny covered under the warranty since they do other jobs then propel the hybrid, i.e. starter generator, alternator?

Hmm I guess if the starter/generator fails the transmission fails, a side effect is that the engine won't crank. Another scenario coud be that the starter works but the batterys don't charge caused by a fault in the inverter, equivalent to a diode failure in an alternator.

 

[TheSEARCH]

Hmm I guess if the starter/generator fails the transmission fails, a side effect is that the engine won't crank. Another scenario coud be that the starter works but the batterys don't charge caused by a fault in the inverter, equivalent to a diode failure in an alternator.

I would guess the motors inside the trans are covered under the 8 year 100K mile warranty as that is part of hybrid system . If they fail my guess a whole new transmission would be the fix. No idea what that cost R&R the engine trans combo plus the part.

 

[AutobahnSHO]

The electric motors are part of the powertrain. I'd have to look at the verbiage of the warranty....

PS- The eCVT also acts kind of like a bicycle- no matter how fast the wheels and chain are already going, the rider can coast or push against the pedals. ICE can do the same....

 

[TheSEARCH]

The electric motors are part of the powertrain. I'd have to look at the verbiage of the warranty....

PS- The eCVT also acts kind of like a bicycle- no matter how fast the wheels and chain are already going, the rider can coast or push against the pedals. ICE can do the same....

Sure its is part of power train BUT its also part of the hybrid system too. Not sure how it would be classified? I would argue its part of the 8 year 100k hybrid warranty

 

[scotty]

Hmm I guess if the starter/generator fails the transmission fails, a side effect is that the engine won't crank. Another scenario coud be that the starter works but the batterys don't charge caused by a fault in the inverter, equivalent to a diode failure in an alternator.

So the inverter is part of the tranny? Since the starter is within the tranny case: then would that mean the starter is part of the tranny, thus warranty coverage? do you know if the inverter is part of the tranny also? Btw thank you for responce

 

[TheSEARCH]

So the inverter is part of the tranny? Since the starter is within the tranny case: then would that mean the starter is part of the tranny, thus warranty coverage? do you know if the inverter is part of the trans also? Btw thank you for responce

No idea where the inverter is I was talking ONLY about the two electric motors. My guess is inverters are not inside.

 

[Darnon]

The inverter/motor controller is on top of the transmission. It's also explicitly one of the components covered.

Depending on your vehicle, electrical drivetrain system components covered by this warranty may include, and are not limited to: high-voltage battery, high-voltage battery connector, high-voltage battery isolation switch (manual disconnect switch), battery pack fan assembly, battery pack sensor module (HBPSM), battery energy control module (BECM), on-board charger, on-board charger fan assembly, inverter system controller (ISC), DC/DC converter, hybrid continuously variable transmission or electric driveline motor and transmission range sensor.

 

[scotty]

No idea where the inverter is I was talking ONLY about the two electric motors. My guess is inverters are not inside.

thank you

 

[scotty]

The inverter/motor controller is on top of the transmission. It's also explicitly one of the components covered.

thank you

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