10. SPINDLE SPEED FUNCTION
B-64693EN-1/01
- 1626 -
Parameter No.
Set value
Meaning
5232
50
Number of teeth of the 2nd gear for the position coder side
5233
70
Number of teeth of the 3rd gear for the position coder side
For the lathe system, up to four gear stages can be set.
(3) Rigid tapping and machines with multiple gears
When performing rigid tapping on a machine that has multiple gears, note the points below.
-
M type gear selection method
M
The CNC determines whether gears need changing using the gear change specification mentioned in
section “SPINDLE SPEED CONTROL”. If the gears need to be changed, the CNC generates the S
function code read signal SF <F007.2> and gear selection signals GR1O, GR2O, and GR3O <F034.0-2>
to notify the PMC. Change gears using the PMC, based on these signals.
-
T type gear selection method
The CNC does not process gear changes. Using the PMC, determine whether gears need changing, and
make the change if needed.
When the CNC has the S function code, it outputs signal SF <F007.2> and S function code signals S00 to
S31 <F022-F025> to the PMC. (However, parameter No. 3705 and its related parameters need to be set
for S code and SF signal output).
The PMC side finds a gear whose spindle speed range includes the spindle speed specified by an S
function code. A selected gear is to be output onto the gear selection signals GR1 and GR2 (G028.1,2 for
the first spindle, G029.0,1 for the second spindle, G029.2,3 for the third spindle, and G031.4,5 for the
fourth spindle) for notification to the CNC. Regardless of the gear selection method, the clutch/gear
selection signals CTH2 and CHT1 (G070.3,2 for the first spindle, G074.3,2 for the second spindle,
G204.3,2 for the third spindle, and G266.3,2 for the fourth spindle) corresponding to a gear change are to
be input for notification through the CNC to the serial spindle control unit.
Changing gears during rigid tapping requires a different process from that for gear changes during normal
machining. As described above, changing gears conforms to the gear change specifications mentioned in
section "SPINDLE SPEED CONTROL" when the M type gear selection method has been selected. With
the T type gear selection method, changing gears conforms to the logic programmed in the PMC.
Regardless of the option's selection, if the range in which the spindle speed specified by the S function
code does not correspond to the currently selected gear, the gears are changed.
The Table 10.13.1 (a) lists the spindle speed ranges for each gear during normal machining (assuming no
machine restrictions) and rigid tapping:
Table 10.13.1 (a)
Gear
Spindle speed range (normal machining)
Lower limit
Upper limit
Low-speed gear
1 revolution
Maximum low-speed gear speed
Maximum spindle motor speed
×
L%
=
Low-speed gear ratio
Medium speed gear
Maximum low-speed gear speed + 1
revolution
Maximum medium-speed gear speed
Maximum spindle motor speed
×
L%
=
Medium speed gear ratio
High-speed gear
Maximum medium-speed gear speed + 1
revolution
Maximum high-speed gear speed
Maximum spindle motor speed
×
L%
=
High-speed gear ratio