Toyota Camry Hybrid AHV40 Manual page 12

TH-12
2. How to Read a Nomographic Chart
D The nomographic chart below gives a visual representation of the planetary gear's rotational direction,
rotational speed, and torque balance.
D In the nomographic chart, a straight line is used to represent the relationship between the rotational speeds
of the 3 gears in the power split planetary gear unit. The rotational speed of each gear is indicated by the
distance from the 0 rpm point. Due to the structure of the power split planetary gear unit, the relationship
between the rotational speeds of the 3 gears is always expressed by a straight line.
D The relationship between the gear rotation directions and the torque that acts on each gear is as described
below.
Due to the structure of this hybrid transaxle, the MG2 motive force acts on the ring gear via the motor speed
reduction planetary gear unit. The illustrations of the power split planetary gear unit operation on the
following pages, represent the rotational direction, rotational speed and torque condition that act on the
ring gear.
D The nomographic charts and the illustrations of the power split planetary gear unit operation for each
vehicle running condition shown on the following pages represent one situation as an example.
"
Nomographic Chart
Sun Gear
(MG1)
(+)
(-)
"
Condition of Power Split Planetary Gear Unit
Rotational Direction
Torque Condition
Normal Driving (During Low Load and Constant-speed Cruising)
THS II (TOYOTA HYBRID SYSTEM II)
A
Carrier Ring Gear
(Engine) (Output)
(+) (+)
rpm
0
(-) (-)
02DTH90Y
Sun Gear (MG1)
+
-
"
Power Split Planetary Gear Unit Operation
Sun Gear
(MG1)
A
Carrier (Engine) Ring Gear (Output)
+
+
A
Carrier
(Engine)
Ring Gear
(Output)
02DTH97Y
+
-