Neutral Coasting
#91
Re: Neutral Coasting
No pressure plate. If you had a solid mechanical conection to the drive train there would be no way to smooth out the pulses of the engine or the sudden shock into the drivetrain causing transmission and gear damage. The one way clutch is most likely a sprage or roller clutch similar to those used in a automatic transmission.(this is a proven technology-- KISS) These OWCs must be have lube or they might seize. I would love to take one of these apart to see what makes them tick.
#92
Re: Neutral Coasting
No pressure plate. If you had a solid mechanical conection to the drive train there would be no way to smooth out the pulses of the engine or the sudden shock into the drivetrain causing transmission and gear damage. The one way clutch is most likely a sprage or roller clutch similar to those used in a automatic transmission.(this is a proven technology-- KISS) These OWCs must be have lube or they might seize. I would love to take one of these apart to see what makes them tick.
GaryG
#93
Re: Neutral Coasting
I just looked it up on my tech data system. It is LIKE a clutch BUT it is not functioning as a clutch and it is not the OWC. It has no system to declutch. It is a damper assembly. Similar to the 944 Porsche automatic transmission. This prevents harsh pulses and shock to damage the drivetrain.
#94
Re: Neutral Coasting
I just looked it up on my tech data system. It is LIKE a clutch BUT it is not functioning as a clutch and it is not the OWC. It has no system to declutch. It is a damper assembly. Similar to the 944 Porsche automatic transmission. This prevents harsh pulses and shock to damage the drivetrain.
GaryG
#95
Re: Neutral Coasting
Because the manual said the damper contain a clutch that slips briefly, I thought that this was the only clutch. But your right, the OWC must be internal to the eCVT and lubed. I've read the Transaxle Control Module can report an OWC error to the PCM to initiate a LOS mode. So this means the OWC function is monitored.
GaryG
GaryG
#96
Re: Neutral Coasting
This type of monitoring started in the early 90's with the fully computer control automatic transmissions. The computer knows what the shaft speeds should be and is constantly comparing target vs actual. BTW the flywheel has NO machined "clutch surface" it is more like a flex plate on an automatic
#97
Re: Neutral Coasting
Back to what I was talking about... Coasting in Neutral.
All I was saying is, there is no physical "mechanical" disconnect when you move the shifter position to "N".
Coasting in N, the generator motor, the traction motor, AND the ICE (when above 40mph ) always spin up in a perfect concert as the wheel speed spins up. Using a custom set-up ScanGauge, I can monitor all of this, and it is not an "approximate" speed match. It is not a computer "syncronizing" the motor speeds to match to be ready when you shift back to drive. Why do I say this? While coasting in neutral there is zero wattage flowing in or out of the battery, and there is zero wattage flowing in and out of both motors.
The 2005 Ford service manual says all electrical power is isolated from the motors in neutral. Actually measuring for this in EV mode, this is for sure true.
In neutral, in EV mode, there is zero wattage flowing in or out of either motor when coasting in neutral. HOWEVER both motors are spinning at the EXACT proportion of wheel speed.
Each miles per hour spins the traction motor 128 RPM.
Each miles per hour spins the generator (in EV) -156 RPM.
There is no maybe.
There is no "in between".
There is no "approximate speeds".
Coasting in N:
At 10 miles per hour, the traction motor is spinning exactly 1280 RPM. EVERY TIME.
At 10 miles per hour (EV), the generator is spinning exactly -1560 RPM. Exactly. EVERY TIME.
It is obvious to me, that the eCVT and all gears are "connected" full time.
The data speaks for itself.
The above is not a theory or conjecture, but hard facts.
-----------------------------------------------------------------------
This part below is my theory.
I 'think' the motor and generator spin when the car is towed wheels down.
Sounds strange, but it could be true.
These motors are not that big.
They are not very heavy or as massive as some people think.
A 100 HP engine is as big as, well, what you have under the hood.
A 100 HP electric motor can fit into a shoe box.
At 95 MPH with ICE on, the traction motor will spin 12,160 RPM.
At 75 MPH with ICE off in tow, the traction motor would spin 9600 RPM.
Sounds practical & possible to tow connected.
At 95 MPH with ICE at 1500 RPM, the generator will spin 9700 RPM.
At 75 MPH with ICE off in tow, the generator would spin 11,700 RPM.
Sounds practical & possible to tow connected.
Being smaller and lighter than most people imagine, there would not be much mechanical drag or rotational "inertia" to just allowing everything to freewheel in neutral. Sounds strange to me, and I'm a little uncomfortable with this process myself, but all the data point in this direction.
Provided this vehicle is "Built Ford Tough" then towing with motors connected, for a relatively small number of miles over the life of the vehicle is likely no stress or strain on them whatsoever.
Thoughts?
-John
All I was saying is, there is no physical "mechanical" disconnect when you move the shifter position to "N".
Coasting in N, the generator motor, the traction motor, AND the ICE (when above 40mph ) always spin up in a perfect concert as the wheel speed spins up. Using a custom set-up ScanGauge, I can monitor all of this, and it is not an "approximate" speed match. It is not a computer "syncronizing" the motor speeds to match to be ready when you shift back to drive. Why do I say this? While coasting in neutral there is zero wattage flowing in or out of the battery, and there is zero wattage flowing in and out of both motors.
The 2005 Ford service manual says all electrical power is isolated from the motors in neutral. Actually measuring for this in EV mode, this is for sure true.
In neutral, in EV mode, there is zero wattage flowing in or out of either motor when coasting in neutral. HOWEVER both motors are spinning at the EXACT proportion of wheel speed.
Each miles per hour spins the traction motor 128 RPM.
Each miles per hour spins the generator (in EV) -156 RPM.
There is no maybe.
There is no "in between".
There is no "approximate speeds".
Coasting in N:
At 10 miles per hour, the traction motor is spinning exactly 1280 RPM. EVERY TIME.
At 10 miles per hour (EV), the generator is spinning exactly -1560 RPM. Exactly. EVERY TIME.
It is obvious to me, that the eCVT and all gears are "connected" full time.
The data speaks for itself.
The above is not a theory or conjecture, but hard facts.
-----------------------------------------------------------------------
This part below is my theory.
I 'think' the motor and generator spin when the car is towed wheels down.
Sounds strange, but it could be true.
These motors are not that big.
They are not very heavy or as massive as some people think.
A 100 HP engine is as big as, well, what you have under the hood.
A 100 HP electric motor can fit into a shoe box.
At 95 MPH with ICE on, the traction motor will spin 12,160 RPM.
At 75 MPH with ICE off in tow, the traction motor would spin 9600 RPM.
Sounds practical & possible to tow connected.
At 95 MPH with ICE at 1500 RPM, the generator will spin 9700 RPM.
At 75 MPH with ICE off in tow, the generator would spin 11,700 RPM.
Sounds practical & possible to tow connected.
Being smaller and lighter than most people imagine, there would not be much mechanical drag or rotational "inertia" to just allowing everything to freewheel in neutral. Sounds strange to me, and I'm a little uncomfortable with this process myself, but all the data point in this direction.
Provided this vehicle is "Built Ford Tough" then towing with motors connected, for a relatively small number of miles over the life of the vehicle is likely no stress or strain on them whatsoever.
Thoughts?
-John
#98
Re: Neutral Coasting
Okay people, here is a lot of information from the FEH Engineers write-up. This is not a patent, but explains much of whats happening in our eCVT.
Example of what's in the document.
"In an electric-only
drive mode (EV mode), where the engine is turned off, the
electric motor draws the power from the battery and provides
propulsion to the vehicle for forward and reverse motions. In
the EV mode, the generator can also be used as a motor to draw
power from the battery to assist the vehicle’s forward launch
due to the one-way clutch at the carrier (engine) shaft. Note
that during an EV mode for reverse launch, the generator cannot
provide assistance since there is no reaction torque available to
transmit the generator torque."
http://www.ece.eng.wayne.edu/~hying/...ogy%202006.pdf
Great reading!
GaryG
Example of what's in the document.
"In an electric-only
drive mode (EV mode), where the engine is turned off, the
electric motor draws the power from the battery and provides
propulsion to the vehicle for forward and reverse motions. In
the EV mode, the generator can also be used as a motor to draw
power from the battery to assist the vehicle’s forward launch
due to the one-way clutch at the carrier (engine) shaft. Note
that during an EV mode for reverse launch, the generator cannot
provide assistance since there is no reaction torque available to
transmit the generator torque."
http://www.ece.eng.wayne.edu/~hying/...ogy%202006.pdf
Great reading!
GaryG
#99
Re: Neutral Coasting
That article adds validity to my thoughts that the generator can spin much faster than we all previously thought.
I have seen the generator spinning 8600+ RPM.
One other owner has also.
The testers in that report also recorded generator speeds over 8600 RPM.
Knowing now that generator speed is only ~6000 at 40 miles per hour, the 40 MPH
EV limit IS NOT DUE TO GENERATOR OVER-SPEED ISSUES!
Knowing what we know now, in theory, EV is possible to at least 60 MPH with the current model, with no harm to the generator/motor.
This points to my earlier theory being correct that the 40 MPH EV limit is a torque limit issue, and not a speed limit issue. -John
I have seen the generator spinning 8600+ RPM.
One other owner has also.
The testers in that report also recorded generator speeds over 8600 RPM.
Knowing now that generator speed is only ~6000 at 40 miles per hour, the 40 MPH
EV limit IS NOT DUE TO GENERATOR OVER-SPEED ISSUES!
Knowing what we know now, in theory, EV is possible to at least 60 MPH with the current model, with no harm to the generator/motor.
This points to my earlier theory being correct that the 40 MPH EV limit is a torque limit issue, and not a speed limit issue. -John
#100
Re: Neutral Coasting
That article adds validity to my thoughts that the generator can spin much faster than we all previously thought.
I have seen the generator spinning 8600+ RPM.
One other owner has also.
The testers in that report also recorded generator speeds over 8600 RPM.
Knowing now that generator speed is only ~6000 at 40 miles per hour, the 40 miles per hour
EV limit IS NOT DUE TO GENERATOR OVER-SPEED ISSUES!
Knowing what we know now, in theory, EV is possible to at least 60 MPH with the current model, with no harm to the generator/motor.
This points to my earlier theory being correct that the 40 MPH EV limit is a torque limit issue, and not a speed limit issue. -John
I have seen the generator spinning 8600+ RPM.
One other owner has also.
The testers in that report also recorded generator speeds over 8600 RPM.
Knowing now that generator speed is only ~6000 at 40 miles per hour, the 40 miles per hour
EV limit IS NOT DUE TO GENERATOR OVER-SPEED ISSUES!
Knowing what we know now, in theory, EV is possible to at least 60 MPH with the current model, with no harm to the generator/motor.
This points to my earlier theory being correct that the 40 MPH EV limit is a torque limit issue, and not a speed limit issue. -John
GaryG