
B–63173EN–1/01
9. SPINDLE SPEED FUNCTION
350
With the spindle serial output or analog output function, specifying the
surface speed (m/min or feet/min) directly in an S command makes it
possible to change the spindle output continuously so as to maintain a
constant surface speed at a programmed point. (For the rapid traverse
command, however, the surface speed for the end point is output at the
beginning of rapid traverse.)
Spindle speed N
r
Surface speed S=2πr·N
Whether or not constant surface speed control is performed is selected by
G code.
G96: Constant surface speed control performed. S in the G96 mode is
m/min or feet/min.
G97: Constant surface speed control not performed. S in the G97 mode
is rev/min.
To perform constant surface speed control, the maximum spindle speed
for each gear select signal issued from the PMC side must be set by
parameter No. 3741-3744.
The gear select signal is a 2 bit code signal (GR1, GR2). The relationship
between the signal and gear number is :
GR1 GR2 Gear number
0 0 1
1 0 2
0 1 3
1 1 4
Assume that gear switching is two stage switching. If the spindle speed
with the output 10 V is 1000 rpm for the low speed gear (G1) and 2000
rpm for the high speed gear (G2), set these speeds to the parameter No.
3741, 3742, respectively. In this case, the spindle output has the linear
relationship shown below:
9.4
CONSTANT
SURFACE SPEED
CONTROL
General
Example of Spindle
Analog Output