Re: torsen tech 101

["Lawson, Dave" <dlawson@ball.com>]

> Dave,
> 
> >dave, thanks for your input.  i hope that i've addressed those issues
> with
> >"torsen tech 102" recently posted, where i specifically address the
> >low-speed manoeuvring issue.  but, it is as you say, it was just that i
> >didn't cover that case specifically in "torsen tech 101".
> 
> I think we are on the same page or paper perhaps.
> 
> >with regards to the locker having a static torque bias of 50:50, you need
> to
> >understand that the locker has no method of apportioning torque.  in
> other
> >words, it has no idea of what 50% is.  unlike the open diff which is of
> >course fixed at this figure.  once you accept that, then you will see
> that
> >the locker in an audi moving in a straight line at constant speed
> >proportions torque based on chassis kinematics, which mirror the weight
> >distribution (in this situation).  this point is made in the jeff daniels
> >book.  the torsen in this same scenario is, like the open diff, operating
> at
> >a 50% torque bias to either axle.
> 
> I have accepted that the open diff is distributes torque equally to both
> output
> shafts while having a speed differential. And I accept that a locked diff 
> maintains equal speed between the output shafts while allowing a varying 
> torque. Sooo, the output torque which a locked diff can distribute is
> based
> on the available tractive force(s) of the output shafts. And these
> tractive
> forces are a function of the vehicle mass over a given wheel (along with 
> a few other parameters). Which would make the available tractive force
> at the front of my ur-q greater than the available tractive force at the
> rear.
> Now what I am saying is, if the torque distributed to the output shafts is
> less 
> than the minimum available tractive force (which is at the rear), this 
> distributed torque is split equally front to rear. The locked diff doesn't
> know
> that the front can handle more torque so it can't send it there. But when
> the 
> distributed torque is greater than the minimum available tractive force 
> (which is at the rear),  that torque which is in excess of the minimum 
> available tractive force at the rear, goes to the front. It has too, the
> rears
> can't start spinning so they accept torque up until the saturation point
> and hold steady there. I do agree that the apportioned torque will follow
> the weight distribution once the output reaches the level I have described
> 
> above.
> 
> >what i would consider "essential" references are the list i included,
> >although the "torsen ii" paper is just in there to show how torsen design
> >has changed over the years...
> 
> Does the "torsen ii"  paper just describe the change from the
> perpendicular
> side gears to the parallel-axis side gears or are there further
> developments?
> -
> Dave Lawson 
>