4 ms·
Yeah, I’d say “not a gearbox”. A gearbox to me is something where there are actual gears engaging and disengaging leading to wear and tear. Doesn’t matter what
by jgilias 2y ago
Yeah, I’d say “not a gearbox”. A gearbox to me is something where there are actual gears engaging and disengaging leading to wear and tear. Doesn’t matter what kind of fancy electronics are then used to hide the mechanical operation from me.
A mechanical CVT with belts and pulleys with changing diameters is even worse.
What the hybrids (e-CVT ones) have though is basically a planetary gear set, where the gears are put together at the factory, and stay there for the life of the car.
To me that’s not a gearbox. At least not in the traditional sense. Transmission sure.
- usrusr 2y agoTo me the key element is that it can run different transmission ratios: wether that's in discrete steps or a continuous ramp, that's an implementation detail. BEV (most of them) don't have that, the Prius has. When I read GP post my (surprised) impression from the "no gearbox" claim was that the Prius started as a serial hybrid. (it did not)
- numpad0 2y agoIs THS actually capable of varying transmission ratio? I thought it can modulate resistance but not actually change gear ratio.
- jgilias 2y agoTransmission ratio yes, as in, what part of engine power gets transmitted to the wheels. Individual gear ratios of course not.
- numpad0 2y agoSo the relationship between engine RPM and wheel RPM is always fixed, only torque split is varied, right? I think that's around where some confusions are coming from.
- jgilias 2y agoNo, the engine can spin without the wheels spinning. Then MG1 gets spun and charges the battery (or spins freely if the battery is full). This page has a neat PSD simulation to help grok what happens: http://eahart.com/prius/psd/ http://eahart.com/prius/psd/ I think it only works from a computer though!