
4. DESCRIPTION OF PARAMETERS
B–63610EN/01
240
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)
5294
Spindle loop gain multioplier in the rigid tapping mode (for gear4)
[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. Find the most
appropriate multipliers by conducting the cutting test and assign them to
the parameters.
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
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.)
α = 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, α, is
La/2048.
Fig.4.25 (b) Connection among the spindle motor, spindle, and position coder
Examples