Guru
Joined: 09/08/2007
Location: AustraliaPosts: 4406
| Posted: 01:46pm 16 Oct 2012 |
The automatic transmission has two input shafts, a solid inner shaft, and a hollow surrounding outer shaft.
These are both splined and "plug into" the back of the torque converter.
Now I am not certain which is which, but for the purpose of explanation here, it probably does not matter.
One of these gearbox input shafts is always directly coupled to the engine, and goes into a hydraulic lockup clutch within the gearbox. When this lockup clutch is engaged, the engine and gearbox are then directly coupled together.
The other gearbox input shaft plugs into the output of the torque converter, and directly drives the internals of the gearbox.
So there are two alternative ways of coupling the engine to the gearbox internals, which both effectively operate in parallel.
1/ Engine > lockup clutch > gearbox ... This is a direct mechanical connection
2/ Engine > hydraulic torque converter > gearbox ... this is a fluid connection
Normally when stationary with the engine running, or when starting off, the torque converter fluid connection must be used.
As a VFD and three phase motor can develop full torque at zero rpm, you don't need the torque converter. Just couple your motor straight into the gearbox, that's all you need.
With an IC engine, in the higher gears, above a certain road speed, the lockup clutch is engaged to eliminate the speed and power loss through the torque converter for better fuel economy.
This lockup clutch is electrically actuated from outside the gearbox, so you can operate it any way you want.
With your electric motor you can either run it direct into the gearbox through one input shaft. Or run it through the lockup clutch into the gearbox through the alternative input shaft, but I cannot see any advantage in doing that.
Cheers, Tony.