20. AXIS CONTROL FUNCTION
Tool rotation for polygonal turning is controlled by CNC controlled axis.
This rotary axis of tool is called Y axis in the following description.
The Y axis is controlled by G51.2 command, so that the rotation speeds
of the workpiece mounted on the spindle (previously specified by
S–command) and the tool becomt the specified ratio.
(Example) Rotation ratio of workpiece (spindle) to Y axis is 1:2, and the
Y axis makes positive rotation.
When simultaneous start is specified by G51.2, the one–rotation signal
sent from the position codes set on the spindle is detected. After this
detection. the Y axis rotation is controoled according to the rotation ratio
(P:Q) while synchronizing with the spindle speed. Namely, the Y axis
rotation is controlled so that the spindle and Y axis stand in a relation of
P:Q. This relation will be maintained until the plygonal turning cancel
command is executed (G50.2 or reset operation). The direction of Y axis
rotation is determined by the code
Q and not affected by the direction of the lposition coder rotation.
Synchronixation of the spindle and Y axis is canceled by the following
When G50.2 is specified, synchronization of the spindle and Y axis is
canceled and the Y axis stops.
This synchronization is also canceledd in the following casset:
i) Power off
ii) Emergency stop
iv) Reset (external reset signal ERS, reset/rewind ignal RRW, and RESET
key on the CRT/MDI panel)
v) Occurrence of P/S alarm Nos. 217 to 221
G00X100. 0Z20.0 S1000.0M03 ; Workpiece rotation speed 1000rmp
G51.2P1 Q2 ; Tool rotation start (tool rotation speed 2000rpm)
G01X80.0 F10.0 ; X axis infeed
G00X100.0 ;X axis escape
G50.2 ; Tool rotation stop
M05 ; Spindle stop Specify G50.2 and G51.2 always in a single block