Re: hydrostatic transmission [was:Matt/Jay/power steering discussion]

[adh@xxxxxxxxxxxxxxxxx (Sandwich Maker)]

" From: farna@xxxxxxx
" 
" I don't know if it would be efficient to remove the transmission
" entirely for a road vehicle. Hydrostatic drive works for bull dozers and
" lawn tractors because there isn't such a wide range of operating
" conditions and speeds. Maybe a two stage pump though, one stage for low
" to medium speeds and another for high speed driving that boosts either
" pressure or volume.

i had infinitely-variable axial piston swashplate pumps and motors in
mind, and i think they have the necessary range.  i never got the
engine speed / pump control entirely sussed [ideally a speed/volume
curve matched to the engine's power], but i was envisioning a
constant-pressure system and that would make motor control easy: as
pressure tries to rise, the control servo increases motor volume; as
pressure tries to fall, the reverse.
________________________________________________________________________
Andrew Hay                                  the genius nature
internet rambler                            is to see what all have seen

adh@xxxxxxxxxxxxxxxxx                       and think what none thought