
4.DESCRIPTION OF PARAMETERS B-63950EN/02
- 372 -
Synchronization
switch
CNC
Detection unit
p/rev
α p/rev
C-axis
Least command increment
0.001deg
Command
pulses
FFG
Gear ratio
A
Detector
×CMR
Slave axis
Gear
ratio B
Error counter
Follow-up
×CMR
Dummy axis
n/m
FFG
N/M
Motor
Detector
Spindle
Error counter Speed/current control
Synchronization
facto
Gear ratio of the spindle to the detector B:
1/1 (The spindle and detector are directly connected to each
other.)
Number of detector pulses per spindle rotation β: 80,000 pulses/rev
(Calculated for four pulses for one A/B phase cycle)
FFG N/M of the EGB dummy axis: 1/1
Gear ratio of the C-axis A: 1/36 (One rotation about the C-axis to 36
motor rotations)
Number of detector pulses per C-axis rotation α: 1,000,000 pulses/rev
C-axis CMR: 1
C-axis FFG n/m: 1/100
In this case, the number of pulses per spindle rotation is:
80000 × 1/1 = 80000
Therefore, set 80000 for parameter No. 7772.
The number of pulses per C-axis rotation in the detection unit is:
1000000 ÷ 1/36 × 1/100 = 360000
Therefore, set 360000 for parameter No. 7773.
(Example 2)
When the gear ratio of the spindle to the detector B is 2/3 for the
above example (When the detector rotates twice for three spindle
rotations)
In this case, the number of pulses per spindle rotation is:
3
160000
=
3
2
80000 ×
160000 cannot be divided by 3 without a remainder. In this case,
change the setting of parameter No. 7773 so that the ratio of the
settings of parameters Nos. 7772 and 7773 indicates the value you
want to set.
1080000
160000
=
3360000
160000
=
360000
3
160000
=
No.5997
No.5996
×
Therefore, set 160000 for parameter No. 7772 and 1080000 for
parameter No. 7773.
As described above, all the settings of parameters Nos. 7772 and 7773
have to do is to indicate the ratio correctly. So, you can reduce the
fraction indicated by the settings. For example, you may set 16 for
parameter No. 7772 and 108 for parameter No. 7773 for this example.