
B-63783EN-1/01 7.FEEDRATE CONTROL/ACCELERATION AND DECELERATION CONTROL
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Table 7.2.6 (e) Example of setting parameters related to limited acceleration curve data
Parameter No. Setting Unit Remarks
Rapid traverse rate 1420 30000. mm/min The ball screw pitch is assumed 15 mm, so that
the rapid traverse rate is 30000 mm/min at the
maximum speed 2000(min
-1
).
Reference acceleration 1671 2750. mm/sec
2
The acceleration a is set.
Speed at P1 6710 5000 0.01% 50% (15 m) is set at P1 because the torque 25
(N⋅m) is up to 1000 (min
-1
).
Speeds at P2 to P4 6711 to 6713 0 0.01% P2 to P4 are skipped because the torque drops
almost linearly from the speed 1000 (min
-1
) to
2000 (min
-1
).
Acceleration at P0 6714,6720
6726,6732
10000 0.01% The acceleration at a speed of 0 is set to 100%
(torque 25 (N⋅m)).
Acceleration at P1 6715,6721
6727,6733
10000 0.01% The acceleration at the speed at P1 is set to
100% (torque 25 (N⋅m)).
Acceleration at P2 to P4 6716 to 6718
6722 to 6724
6728 to 6730
6734 to 6735
0 0.01% No acceleration need be set because P2 to P4
are skipped.
Acceleration at P5 6719,6725
6731,6737
4800 0.01% The acceleration at the speed at P5 (30000
mm/min) is b, and the ratio of b to the reference
acceleration a is set. (0.48 = 1320/2750)
With the above parameter settings, the limited acceleration curve will
be as shown in the figure below: At P0, the speed is 0 and the
acceleration is 2750 mm/sec
2
, at P1, the speed is 15000 mm/min and
the acceleration is 2750 mm/sec
2
, P2 to P4 are skipped, and at P5, the
speed is 30000 mm/min and the acceleration is 1320 mm/sec
2
.
P5
P1
P0
0
500
1000
1500
2000
2500
3000
0 15000 30000
Speed mm/min
Acceleration mm/sec/sec
Fig. 7.2.6 (e) Example of limited acceleration curve
NOTE
The values in the model αC12/2000 speed-torque
characteristic diagram are just typical ones. The
values will change depending on the digital servo
software, parameters, input voltage, and other
factors.
The optimum acceleration will, therefore, change
due to the characteristics of the machine.