Page 559 - eProceeding for IRSTC2017 and RESPeX2017

The implicit relationship between belt length and running radii can be defined as:

( ) ( ) ( ) (3)

( ) (4)

The relationship between running radii and pulley position can be given as:

( ) ( ) (5)

( ) ( ) (6)

By using equation (3) and (4), for c = 260 mm, and L= 853 mm, the relationship between running radii and belt wrapped
angle, ϴ, is shown in fig. 1.(b). By using equation (5), (6) and data from fig. 3.(a). By varying CVT ratio from 0.9 up to 2.8,
the relationship between pulley positions and CVT ratio can plotted in fig. 3.(b).

(a) (b)

Fig. 3. (a) Relationship between running radii and belt wrapped angle;
(b) Relationship between pulley positions and CVT ratio

3. Gear Reducer and Power Cam Mechanism

The gear reducers are coupled with the servomotor shaft is shown in fig. 4, a gear reducer serves as a speed reducer and
torque multiplier. The gear reducer output is connected to power cam mechanism for shifting the pulley sheaves. The power
cam mechanism is used to move the pulley sheaves axially. The combination of gear reducers and power cam mechanism is
used to help the motor in providing significant torque to turn the power cam mechanism. It converts every 360 of rotation
into 2 millimeters axial movement. Therefore the motor have to turn 12.3 rev in order to turn 1 rev of the CAM. In order to

turn 75.08 to expend the cam to limit, the motor have to turn .

557 | V O L 1 1 - I R S T C 2 0 1 7 & R E S P E X 2 0 1 7