No, this is a common misconception. I knew nothing about it when I first started looking into the Prius, but I've since found several articles on how it works.
The Hybrid Synergy Drive system has a planetary gearbox coupling the ICE and two electric drive motor/generators. There is no clutch or liquid coupling, all three are always directly engaged and gearing is never changed. What is changed is the relative directions and force applied by all three power units to the coupling, which simulates a constantly variable transmission by the control system's integrating the torque outputs through the coupling dynamically. One could more correctly describe the drive system as providing constantly optimized torque based on demand rather than as a continuously variable transmission. Here are a couple of discussions, in no particular order, for your enjoyment: <http://prius.ecrostech.com/original/Understanding/ ContinuouslyVariableTransmission.htm> <http://www.insightcentral.net/KB/compare/prius-powertrain.html> <http://www.toyota.co.jp/en/tech/environment/ths2/hybrid.html> a picture of the power unit: <http://www.lrz-muenchen.de/~u7224ac/www/hybrid.jpg> an interactive simulation: <http://eahart.com/PSDAnim.swf> Fun stuff, a fascinating study. The simulation is fun to play with. Godfrey On Dec 29, 2006, at 3:54 AM, Paul Stenquist wrote: > It has a continuously variable transmission. >> >>> Only difference over a regular car would be some electronics, >>> electric >>> motor, and batteries. >> >> I'm not sure what you mean by this. Yes, it does use a four cylinder >> internal combustion engine and a differential, suspension and brakes. >> As a difference, it has no transmission, no starter motor, two drive/ >> generator motors, and a drive battery pack in addition to the >> standard 12V gel cell battery that your car uses. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
