7. Feed Functions
7.5 Inverse Time Feed; G93
114
Example of program
When using inverse time feed during tool radius compensation
N01 G90 G00 X80. Y-80. ;
N02 G01 G41 X80 Y-80. D11 F500 ;
N03 X180. ;
N04 G02 Y-280. R100. ;
N05 G03 Y-480. R100. ;
N06 G02 Y-680. R100. ;
N07 G01 X80. F500 ;
N08 Y-80. ;
N09 G04 X80. Y-80. ;
N10 M02 ;
Feed per minute
N01 G90 G00 X80. Y-80. ;
N02 G01 G41 X80. Y-80. D11 F500 ;
N03 X180. ;
N04 G93 G02 Y-280. R100. F5 ;
N05 G03 Y-480. R100. F5 ;
N06 G02 Y-680. R100. F5 ;
N07 G94 G01 X80. F500 ;
N08 Y-80. ;
N09 G04 X80. Y-80. ;
N10 M02 ;
Inverse time feed
(Fig. 3)
N4
N6
N5
Comparison between feed per minute and inverse time feed
(Assuming that tool radius is 10. [mm]) (Unit: mm/min)
Feed per minute
Inverse time feed
Location
Sequence
No.
Feedrate of
tool center
Feedrate of
cutting point
Feedrate of
tool center
Feedrate of
cutting point
N04
F500 F450 F550 F500
N05
F500 F550 F450 F500
N06
F500 F450 F550 F500
↓
↓
The block seam
protrudes due to
the cutting speed
change at the
block seam.
The feedrate
follows the
command
regardless of the
tool radius.