
H.DETAILS OF HIGH-SPEED AND HIGH-PRECISION ADJUSTMENT APPENDIX B-65270EN/05
- 500 -
[Guideline for adjustment value setting]
Empirically, the values below are adequate. For the parameter
numbers, refer to the parameter manual of each CNC.
High-rigidity small machines:
F4000 for R5 (889 mm/sec
2
)
Medium-size or small machining centers with a relatively high
rigidity:
F3000 for R5 (500 mm/sec
2
)
Large machines:
F2500 for R5 (347 mm/sec
2
)
Large machines with a very high rigidity:
F2000 for R5 (222 mm/sec
2
)
[Actual adjustment]
Fig. H (o) shows the results of setting R5 mm and F3000 with the
arc radius based feedrate clamp function for Fig. H (k). Fig. H
(o) indicates that the figure errors at the entries and exits of the
arc areas have been reduced.
The figure display is 5 mm wide.
The error is 10
µ
m in size.
The figure errors
at the entries and
exits of each arc
area have been
reduced.
Fig. H (o) Arc radius based feedrate clamping
(5) Adjustment of an allowable feedrate difference of the feedrate difference
based corner deceleration function
[Purpose of adjustment]
In the program shown in Fig. H (p), the feedrate along each axis
changes to a great extent at each block joint. With a
high-precision high-speed system, the CNC reads programmed
figures beforehand. If the feedrate along each axis changes at a
block joint, such a system can decrease the feedrate by a
parameter-specified allowable feedrate difference to reduce a
shock and figure error at the block joint. Acc./dec. is performed
based on the time constant for acc./dec. before interpolation. A
more reduced corner feedrate makes a figure error improvement
to a greater extent, but requires a longer machining time. Set a
reduced corner feedrate to a highest possible value as long as an
allowable figure error is obtained.