Yaskawa MP920 User's Manual Design - Manual (Page 145)

4.3 Position Control
4-31
4
Electronic Gear Parameter Setting Example (A): With Ball Screw
In the above machine system, if the requirement is reference unit = output unit = 0.001 mm,
the setting of each parameter will be as follows:
•
•
• No.21 = 7
• No.22 = 5
No.21
No.22 Servomotor
Gear Ratio
Machine Gear
Ratio • These parameters are used to set the gear ratio between the motor and the
load. When the motor axis has rotated m times and the mechanical config-
uration allows the load axis to rotate n times, set the following
values: No. 21 = m rotations
No. 22 = n rotations
• Setting range: 1 to 65,535 [rotations]
Setting Examples
Therefore, set the following values: No. 21 = 21
No. 22 = 4
1
Table 4.11 Electronic Gear Parameters and Constant (cont’d)
Servo Fixed
Parameter No.
Name Description Initial
Value
7 rotations
Motor axis
m rotations
Load axis n rotations
4 rotations
3 rotations
9 rotations
Gear ratio =
n
m
3
7
4
9 4
21
× = =
m
n
7 rotations
Motor
Ball screw pitch
P = 6 mm/rotation
5 rotations
No.19 = =
6000
6 mm
0.001 mm
Gear ratio = =
n
m
5
7