Control Units For Speed/Torque Control - Omron CJ1W-NC271 - 12-2009 Operation Manual

Control Units
Position command value: 1,000
(command unit)
Command Unit Setting
Example
Feed screw pitch
(Servomotor encoder resolution × 4) × (deceleration ratio)
7-2-2

Control Units for Speed/Torque Control

274
Servo Drive
Electronic gear
Encoder resolution × 4
G1
=
G2 Command unit
8192
=
1000
Consider the following positioning example.
N
Servomotor Electronic gear ratio
M: Deceleration gear ratio
V: Feed speed of object being positioned (mm/s)
P: Feed screw pitch (mm/rotation)
R: Servomotor encoder resolution (pulses/rotation)
The equation for calculating the distance traveled per Servomotor encoder
resolution pulse is as follows:
The Servo Drive performs control internally at four times the Servomotor's
encoder resolution. Therefore, in the above equation, the Servomotor's
encoder resolution is multiplied by four. If the command unit used is mm, the
electronic gear ratio is set as the reciprocal of the above equation and G1/G2
is set as follows:
G1
Command unit (mm):
G2
If the command unit used is 0.01 mm (= 10 μm), the unit is converted by mul-
tiplying the travel distance per encoder resolution pulse by 100, and the elec-
tronic gear ratio is set as follows:
Command unit (0.01 mm):
The unit used for the speed command value in speed control is the percent-
age (unit: 0.001%) of the Servo Drive's/Servomotor's momentary maximum
rotation speed. The unit used for the torque command value in torque control
is the percentage (unit: 0.001%) of the Servo Drive's/Servomotor's momen-
tary maximum torque. The Servomotor's momentary maximum rotation speed
and momentary maximum torque depend on the Servomotor model.
(Encoder resolution; 2,048 pulses/rotation)
8,192 pulses
1 rotation (8,192 pulses)
V
M
Object being Feed screw pitch
positioned
P (mm/rotation)
=
R (pulses/rotation) × 4 × M
R (pulses/rotation) × 4 × M
=
P (mm/rotation)
R (pulses/rotation) × 4 × M
G1
=
P (mm/rotation) × 100
G2
Section 7-2
Servomotor
P
(mm/pulse)
(pulses/mm)
(pulses/0.01 mm)