
4.DESCRIPTION OF PARAMETERS B-64120EN/01
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5291 Spindle loop gain multiplier in the rigid tapping mode (for gear 1)
5292 Spindle loop gain multiplier in the rigid tapping mode (for gear 2)
5293 Spindle loop gain multiplier in the rigid tapping mode (for gear 3)
Spindle loop gain multioplier in the rigid tapping mode (for gear4)
5294
[Data type] Word type
[Valid data range] 0 to 32767
Set the spindle loop gain multipliers for gears 1 to 4 in the rigid
tapping mode. The thread precision depends on the multipliers.
Conduct cutting tests, and make fine adjustments to obtain an
optimum value.
NOTE
These parameters are used for analog spindles.
Loop gain multiplier = 2048 × E/L × α × 1000
where;
E : Voltage in the velocity command at 1000 min
-1
L : Rotation angle of the spindle per one rotation of the spindle
motor
α : Unit used for the detection
Examples
Spindle
Motor
Spindle
Position
coder
1 : 1 : 2
P.C
When the spindle motor, spindle, and position coder are connected as shown
left, let the variables be as follows:
E = 1.667 (V) (A motor speed of 6000 min
-1
corresponds to 10 V.)
L = 360
°
(One rotation of the spindle corresponds to one rotation of the
spindle motor.)
a = La/4096
= 720
°
/4096
= 0.17578
La = 720
°
(= 360
°
×
2. One rotation of the position coder corresponds to two
rotations of the spindle.)
4096 = The number of detected pulses per rotation of the position coder
Gear ratio between the spindle and the position coder
1:1 0.08789 degrees
1:2 0.17578 degrees
1:4 0.35156 degrees
1:8 0.70313 degrees
According to above ratio the loop gain multiplier is calculated as
2048
×
1.667/360
×
0.17578
×
1000 = 1667
* When the position coder which is built in a spindle motor sends 512 pulses
per rotation, the unit used for the detection, a, is La/2048.
Fig.4.23 (b) Connection among the spindle motor, spindle, and position coder