
1.AXIS CONTROL B-63323EN-1/03
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Previous upper dead point
Previous lower dead point
New lower dead point
Changing the lower dead point
The tool first moves to the upper dead point, then to the new lower
dead point.
Once movement to the upper dead point has been completed, the
previous chopping delay compensation is set to 0, and chopping
delay compensation is performed based on the new data.
- Chopping delay compensation function
When high-speed chopping is performed with the grinding axis, a servo
delay and acceleration/deceleration delay occur. These delays prevent
the tool from actually reaching the specified position.
The CNC measures the difference between the specified position and
the actual tool position, and performs chopping delay compensation to
compensate for the difference.
To compensate for this displacement, an amount of travel equal to the
distance between the upper and lower dead points, plus an appropriate
compensation amount, is specified. When a chopping command is
specified, the feedrate is determined so that the chopping count per unit
time equals the specified count. When the difference between 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. 1881, 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. 1827), the control unit no longer applies compensation,
allowing the tool to continue moving at its current feedrate.
A percent 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. 1196.