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3.2
Setting User Constants According to Host Controller
85
3)
Examples of Setting an Electronic Gear Ratio for Different Load Mechanisms
Ball Screw
Reference unit: 0.001 mm
Load shaft
Incremental
encoder:
Ball screw
pitch: 6 mm
Travel distance per
revolution of load shaft
Electronic gear ratio
Preset
values
Cn-24
Cn-25
B
A
=
2048
×
4
×
1
6000
×
1
=
Cn-
24
Cn-
25
=
6
mm
0.001
mm
=
6000
8192
6000
2048 pulses per revolution
Disc Table
Reference unit:
0.1
°
Gear ratio:
3 : 1
Load shaft
Incremental encoder:
2048 pulses per revolution
Travel distance per
revolution of load shaft
Preset
values
24576
3600
Cn-24
Cn-25
0.1
°
360
°
=
=
3600
Electronic gear ratio
B
A
=
2048
×
4
×
3
3600
×
1
=
Cn-
24
Cn-
25
Belt & Pulley
Pulley diameter:
100 mm
Absolute encoder:
1024 pulses per revolution
Cn-24
Cn-25
Load shaft
Reference unit: 0.0254 mm
Gear ratio:
2.4 : 1
Travel distance per
revolution of load shaft
=
3.14
x
100
mm
0.0254
mm
=
12362
Electronic gear ratio
B
A
=
1024
×
4
×
2.4
12362
×
1
=
Cn-
24
Cn-
25
49152
61810
=
9830.4
12362
=
49152
61810
Preset
values
4)
Control Block Diagram for Servopack for Position Control
DR2 Servopack for position control
Feed-forw
ard gain
Primary
lag filter
Bias
COIN
signal
Speed
loop
Current
loop
SGM
Servomotor
Encoder
Error
counter
Frequency
dividing
Differ-
entiation
Reference
pulse
PG signal
output
Smooth
−
ing
3