Continuously Variable Transmission/Transaxle: Description and Operation

Transaxle Description

Transaxle Components
The electronically controlled, continuously variable transmission (eCVT) has the following internal components:
^ 65 kW traction motor
^ 28 kW generator
^ One-way clutch
^ Planetary gearset

Range Selection:

Park
With the range selector in PARK:
^ the parking pawl locks the output shaft to the case.
^ the engine may be started.
^ the ignition key can be removed.
^ the ignition switch can be cycled from OFF to START or RUN.

Reverse
With the range selector in REVERSE:
^ the vehicle may be operated in a rearward direction.
^ reversing lamps are illuminated.
^ if the vehicle is not started, there is no reverse gear engagement.

Neutral
With the range selector in NEUTRAL:
^ no power flows through the transmission.
^ the output shaft is disengaged from the drive wheels.

Drive
The range selector DRIVE position provides:
^ low speed driving.
^ acceleration.
^ cruise conditions.
^ deceleration.
^ maximum fuel economy during normal operation.

If the vehicle is not started, there is no forward gear engagement.

Low
The range selector LOW position provides:
^ engine braking.
^ improved traction on slippery roads.

If the vehicle is not started, there is no forward gear engagement.

Shift Interlock System
The shift interlock system prevents a shift out of PARK unless the brake pedal is depressed. The shift interlock system has a shift lock actuator mounted on the floor shifter assembly. If the ignition switch is in the RUN position, the shift actuator is continually on unless the brake pedal is depressed.

External Controls
The external control of the continuously variable transmission (eCVT) is mechanically controlled by a cable connected to the floor shifter. The floor shifter position determines park, reverse, neutral, drive, and low modes.

The motor/electronics cooling system has the following components:

Motor Electronics Cooling System
The vehicle uses a pump driven cooling system (referred to as the motor electronics cooling system) to transfer heat generated by the CVT and the hybrid electric vehicle (HEV) battery pack to the atmosphere. The system uses a coolant-to-air radiator design.