
B-63944EN-2/02 PROGRAMMING 8.AXIS CONTROL FUNCTIONS
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the displacement of the tool from the upper dead point and the
displacement of the tool from the lower dead point becomes smaller
than the setting of parameter No. 8377, after the start of chopping, the
control unit performs compensation.
When compensation is applied, the chopping axis moves beyond the
specified upper dead point and lower dead point, and the chopping
feedrate increases gradually.
When the difference between the actual machine position and the
specified position becomes smaller than the effective area setting
(parameter No. 1826), the control unit no longer applies compensation,
allowing the tool to continue moving at its current feedrate.
A coefficient for the compensation amount for the displacement
generated by the servo delay incurred by chopping and the delay
incurred during acceleration/deceleration can be specified in
parameter No. 8376.
- If servo delay compensation can cause the chopping speed to exceed the
maximum allowable chopping feedrate:
Servo delay compensation during a chopping operation can gradually
increase the chopping speed. If the chopping speed is about to
exceed the maximum allowable chopping feedrate, it is clamped to the
maximum allowable chopping feedrate. In this case, the chopping
axis may go beyond the bottom dead point. In servo delay
compensation, the distance specified in a movement command is
increased by a compensation amount that matches the distance yet to
go before the top and bottom dead points are reached, and the
chopping speed is also increased, so that the distance yet to go can be
compensated for.
If the chopping speed is clamped to the maximum allowable chopping
feedrate, a distance specified in the movement command is increased,
but the clamped speed remains unchanged. For this reason, the
chopping axis can go beyond the bottom dead point.