Locomotives have been doing it for a long time -- On Fri, Nov 18, 2011 at 12:02 PM, G Mann <g2ma...@gmail.com> wrote:
> All good points. > > The end result, in any case is to place the engine at the ''sweet spot" as > much as possible, even on the heavy haul big rigs. > > If running a small engine at speed to run a generator worked, surly someone > would be doing it now. Why not? > > Grant... > AZ.... > > On Fri, Nov 18, 2011 at 10:14 AM, Fmiser <fmi...@gmail.com> wrote: > > > > G Mann wrote: > > > > > That would be 28 Peak HP.... so you need those 18 gears to > > > keep the little engine exactly in BOTH it's best torque and > > > best Horsepower sweet spot to gain max efficiency to achieve > > > that "perfect" mileage. > > > > And if the only duty of the engine was to run the generator that > > powers the electric motors it _would_ be running at exactly it's > > sweet spot. > > > > And then, just to pick at nits, *smiles* there is hardly any big > > trucks on the road with an 18 speed transmission. The 18 speed's > > primary duty is for off-road service. 9 and 10 speed are the > > most common. It's not rare to find a 13 speed, and a 15 speed, > > though unusual, is not unheard of. > > > > Since I'm on this rabbit trail already, I'll continue... > > > > The RoadRanger type transmissions used in the big trucks today > > are a 5 speed main gearbox with auxiliary gearing. Using air > > pressure from the air brake system, there are "switches" on the > > shifter that operate "solenoids" to change the auxiliary gears. > > It can be a large ratio change (range) or a small ratio change > > (split). > > > > 9-speed = no splits, 5 in low range, 4 in high range > > 10-speed = no splits, 5 lo, 5 hi > > 13-speed = 5 lo, 4 hi with splits > > 15-speed = 5 lo with splits, 4 high > > 18-speed = 5 low with splits, 4 high with splits > > > > -- Philip > > > > _______________________________________ > > http://www.okiebenz.com > > For new and used parts go to www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > > > To Unsubscribe or change delivery options go to: > > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > > _______________________________________ > http://www.okiebenz.com > For new and used parts go to www.okiebenz.com > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > -- OK Don 2001 ML320 1992 300D 2.5T 1990 300D 2.5T 1997 Plymouth Grand Voyager _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
