|
19 April 2000, Tokyo: Mitsubishi Motors Corporation announces that
it has completed development of the GDI-CVT(*1) new age powertrain,
which returns very low fuel consumption and delivers sporty and smooth
road performance. Incorporating integrated management of MMC's low-consumption,
high-output GDI engine and of a new advanced CVT unit, the GDI-CVT powertrain
will drive a new 5-number body size MMC model to be launched in the
near future.
The GDI-CVT new age powertrain exploits to the full the strengths
of its two major components: the At Will Torque Control ability, and
the very wide low-consumption operating zone of the GDI engine; and
At Will Shifting ability to control instantly and continuously a very
wide range of gear ratios in the CVT. Integrated management of these
strengths realizes significant reductions in energy losses and a 10
per cent improvement in fuel consumption compared with the current GDI
and automatic transmission powertrain, while also delivering silky-smooth
power and performance with excellent response and jerk-free shifting.
The INVECS(*2) -III CVT smart transmission incorporates MMC's proprietary
Adaptive Shift Control and Optimal Shift Control technologies that enhance
easy-to-drive qualities by automatically selecting the gear ratio best
suited to road conditions and to the driver's individual style and preferences.
Available is the INVECS-III Sport Mode 6-CVT transmission that features
a manual shift override, enabling the enthusiast driver to enjoy lag-free
response and enhanced driving pleasure.
(*1) Continuously Variable Transmission
(*2) Intelligent & Innovative Vehicle Electronic Control System

GDI-CVT
1. Development goal
The new age powertrain has been developed using integrated GDI and
CVT management to realize outstanding road performance characterized
by very low fuel consumption and superior driveability.
2. Features
(1) Integrated GDI-CVT management
- The GDI-CVT powertrain first of all exploits the "At Will Torque
Control" characteristic inherent in GDI technology - in other words,
the ability to regulate torque very precisely - to realize practically
lag-free response. The system also uses a new and powerful 32-bit
single chip microprocessor to integrate management of the GDI engine
and the CVT. By means of highly responsive and high-precision control
of CVT hydraulic pressure, the microprocessor keeps pulley pressure
at the minimum required for any given engine torque, across the whole
torque band. This has made it possible to significantly reduce the
friction losses suffered in port-injection gasoline engine and CVT
arrangements from the need to apply a greater than necessary pulley
pressure to prevent slippage between belts and pulleys. The happy
result is lower fuel consumption.
- The GDI-CVT powertrain also exploits the "At Will Shifting" characteristic
of the CVT, which permits fast and continuous shifting over a very
wide range of gear ratios. This makes it possible to extract to the
full the low fuel consumption performance of the GDI engine at low
engine speeds - something not possible with a conventional automatic
transmission.
- The GDI-CVT arrangement also enables injection of fuel is to be
cut off over a wider engine speed band when decelerating, again contributing
to a reduction in fuel consumption.
The low fuel consumption qualities of the GDI-CVT powertrain do not
result in any sacrifice in performance, however. When the driver puts
his foot down, response is instantaneous and the engine revs fast to
generate maximum output for stress-free and sporty motoring.
(2) Evolution from INVECS-II to INVECS-III CVT
- From the INVECS-II smart stepped automatic transmission, INVECS-III
CVT inherits Optimum Shift Control, which uses a shift pattern based
on a large number of average drivers, and Adaptive Shift Control, which
tailors shifting to accommodate individual driving styles and preferences.
It also exploits the At Will Shifting properties of a CVT, with its
step-less shifting, to logically and instantly select the optimum gear
ratio for any given situation. INVECS-III CVT also eliminates the unpleasant
jerkiness that accompanies shifting.
- Available, the INVECS-III Sport Mode 6-CVT features six fixed pulley
diameter settings and a manual shift gate to enable the driver to override
the automatic and select his gear of choice. On top of the silky-smooth
performance delivered by the INVECS-III CVT, this version provides six
gear ratios optimally suited to sporty driving and enhances the fun-to-drive
qualities of the car for the enthusiast driver.
|