Re: 90q Seat Belt Question

[ScharfR@aol.com]

In a message dated 97-06-25 15:14:56 EDT, STEADIRIC@aol.com writes:

<< That's the Procon TEN system, it's designed to make sure the seatbelts 
 are tight AND yank the steering wheel into the dash in a HARD frontal 
 impact.  >>

[small buzzing sound]  Actually, cars in the U.S. only had the safety belt
TENsioning portion of the system installed.  The PROgrammed CONtraction of
the steering wheel would have contravened the intent of the FMVSS requirement
for energy-absorbing steering columns.  (From the above, you may deduce where
the term Procon Ten came from.)

As to the function of the mechanical seat belt tensioners, the idea is not
just to take the slack out of the belt system.  It also winds in a certain
length of webbing onto the take-up reel.  In a conventional belt system, it
is not uncommon for a combination of webbing stretch and belt spool-out (even
with a mechanically locked reel) to allow an undesirabe degree of forward
torso excursion (plain talk - it puts the body a little closer to the scene
of the crime).  A belt tensioning system "reels-in" the torso and better
holds the occupant in a position where the belts and air bag (supplemental
restraint) are most effective.

I believe Audi dropped the award-winning mechanical belt tensioning system
when they went with air bags on all cars worldwide.  Seems that the sensors
and triggering mechanism for pyrotechnic belt tensioners were all in place
thanks to the air bags, so a redundant mechanical system was extra baggage,
weight, complexity, cost ...