
B–63503EN–1/01
7. FEEDRATE CONTROL/ACCELERATION
AND DECELERATION CONTROL
289
G code Description
G25 Spindle speed fluctuation detection off
G40 Cutter compensation cancel
G40.1 Normal direction control cancel mode
G49 Tool length compensation cancel
G50 Scaling cancel
G50.1 Programmable mirror image cancel
G64 Cutting mode
G67 Macro modal call cancel
G69 Coordinate rotation cancel
G80 Canned cycle cancel
G94 Feed per minute
G97 Constant surface speed control cancel
For a cutting feed command in feed per minute mode, Look–ahead control
of multiple blocks can be performed, and linear acceleration/deceleration
can be performed for a programmed feedrate (before interpolation).
When acceleration/deceleration is performed after interpolation,
acceleration/deceleration is performed for the data resulting from
interpolation, which changes the interpolation data. For
acceleration/deceleration before interpolation, on the other hand,
acceleration/deceleration is performed for the feedrate data before
interpolation, so that the interpolation data is not changed by
acceleration/deceleration. Therefore, interpolation data can always be
aligned with a specified line or curve to eliminate any machining profile
errors caused by a delay in acceleration/deceleration.
Linear acceleration/
deceleration before
interpolation
Calculation
of feedrate
Specified
feedrate
Calculation of
interpolation
Acceleration/
deceleration af-
ter interpolation
Servo
control
Pulse
distribution
Linear interpolation,
circular interpolation, etc.
Advanced preview linear
acceleration/deceleration
before interpolation