21. AXIS CONTROL FUNCTIONS
The rotation direction of the workpiece axis depends on the rotation
direction of the tool axis. That is, when the rotation direction of the
tool axis is positive, the rotation direction of the workpiece axis is also
positive; when the rotation direction of the tool axis is negative, the
rotation direction of the workpiece axis is also negative. However, by
specifying a negative value for L, the rotation direction of the
workpiece axis can be made opposite to the rotation direction of the
During synchronization, the machine coordinates of the workpiece
axis and EGB axis are updated as synchronous motion proceeds. On
the other hand, a synchronous move command has no effect on the
absolute and relative coordinates.
3 Termination of tool axis rotation
In synchronism with gradual stop of the tool axis, the workpiece axis
is decelerated and stopped. By specifying the command below after
the spindle stops, synchronization is canceled, and the EGB
synchronization switch is opened. At this time, the synchronization
mode signal (SYNMOD) is turned off.
4 Cancellation of synchronization
The position of the workpiece axis after travel during synchronization
is reflected in the absolute coordinates when synchronization is
canceled; from this point, absolute command programming is enabled
for the workpiece axis. By setting bit 0 (HOBRST) of parameter No.
7700 to 0, synchronization can also be canceled upon reset.
* The synchronization mode is canceled by a servo alarm, PS000
alarm, or emergency stop.
When a helical gear is to be produced, the compensation of workpiece axis
rotation is needed according to the travel distance on the Z–axis (axial
Helical gear compensation is performed by adding compensation pulses
calculated from the formula below to the workpiece axis:
Compensation angle =
Z sin (P)
360 (For metric input)
Compensation angle =
Z Q sin (P)
360 (For inch input)
Compensation angle: Signed absolute value (deg)
Z: Amount of travel on the Z–axis after the specification of G81
(mm or inch)
P : Signed gear helix angle (deg)
T: Number of teeth
Q: Module (mm) or diametral pitch (inch
The values of P, T, and Q are to be programmed.
D Helical gear