Eastern Automotive Warehousing/Auto Machinery - Autosphere

New Technologies
Automatic Transmissions—
Not What They Used to Be
Unless you are in the business of restoring old cars, you can say
goodbye to Powerglides, C-4s, FMXs, Turbo 350 and 400s, and the
likes. There is barely any car or light truck left in the industry that
is available with a three-speed automatic transmission and before
long, even the four-speed trannies will be history. Right now, we are
looking at fi ve, six, seven, and even eight speed automatic gearboxes
and more and more automakers are adopting the CVT system for
better fuel economy. And that’s not it!
As these words are
being written, one of
the most advanced
up. You probably
heard about toroidal
transmissions
“regular” automatic trans-
in light machinmissions
has to be ZF’s
ery or in Formula
8-speed hybrid transmis-
One. Expect them
sion. Thanks to advanced
sooner or later in
electronics and software
regular passen-
controls, this gearbox Toroidal transmissions may very well be the way of the future. ger cars. For
outperforms most drivers
now, they seem
with manual transmissions not only in per- headed towards medium-duty trucks as
formance, but also in fuel economy—when it was announced recently. As a matter of
equipped with the optional start-stop fact, British-based Torotrak has partnered
function (which shuts the engine off when with Allison Transmissions to develop a
the vehicle is stopped at a red traffi c light), medium-duty truck transmission that will
this transmission, according to ZF, is 11% feature Torotrak’s full-toroidal transmis-
more economical than its predecessor. sion technology. The system works with a
According to Dr. Michael Paul, executive full-toroidal variator that consists of a set
president, Technology at ZF, around half of discs and rollers instead of a system of
of the potential was achieved by reducing gears. Consequently, it makes the infi nite-
the activation energy of the transmission ly variable transmission torque-controlled
and by moving the operating point of the instead of ratio-controlled. According to
engine… all thanks to electronic controls! Torotrak, this technology offers improved
The 8-speed hybrid transmission by ZF fuel-saving, emissions, and refinement
communicates with other subsystems in benefi ts. Add to that an improved riding
the vehicle via a multitude of interfaces. experience. Commercial vehicles will sure-
“The transmission in a hybrid vehicle has ly be taking advantage of the Torotrak sys-
up to 400 signal interfaces to other comtem but already, there are plans to include
ponents,” says Dr. Paul.
it to passenger cars and light trucks.
Say hello to the toroidal
transmission
Recently, many manufacturers opted for
the new Dual-Clutch transmission, a really
new way of making gears shift. But now,
there is something even newer coming
Éric Descarries
104420.662@compuserve.com
For instance, BMW has included the
Torotrak technology in its ActiveHybrid
concept car and Mercedes-Benz has also
unveiled it in its BlueHybrid concept
vehicle too. Who’s next?
| www.autosphere.ca | December 2009 | CarCare Business | 31