PROGRAMMING
B–63844EN/02
4. INTERPOLATION FUNCTIONS
49
To perform tool offset in the cylindrical interpolation mode, cancel any
ongoing cutter compensation mode before entering the cylindrical
interpolation mode. Then, start and terminate tool offset within the
cylindrical interpolation mode.
In the cylindrical interpolation mode, the amount of travel of a rotary axis
specified by an angle is once internally converted to a distance of a linear
axis on the outer surface so that linear interpolation or circular
interpolation can be performed with another axis. After interpolation,
such a distance is converted back to an angle. For this conversion, the
amount of travel is rounded to a least input increment.
So when the radius of a cylinder is small, the actual amount of travel can
differ from a specified amount of travel. Note, however, that such an error
is not accumulative.
If manual operation is performed in the cylindrical interpolation mode
with manual absolute on, an error can occur for the reason described
above.
Specified value
The actual amount
of travel
2×2πR
MOTION REV
MOTION REV
MOTION REV
:
The amount of travel per rotation of the rotation axis (Set-
ting value of parameter No. 1260)
R
:
:Rounded to the least input increment
Workpiece radius
=
2×2πR
In the cylindrical interpolation mode, an arc radius cannot be specified
with word address I, J, or K.
If the cylindrical interpolation mode is started when cutter compensation
is already applied, circular interpolation is not correctly performed in the
cylindrical interpolation mode.
In the cylindrical interpolation mode, positioning operations (including
those that produce rapid traverse cycles such as G28, G53, G73, G74,
G76, G80 through G89) cannot be specified. Before positioning can be
specified, the cylindrical interpolation mode must be cancelled.
Cylindrical interpolation (G07.1) cannot be performed in the positioning
mode (G00).
In the cylindrical interpolation mode, a workpiece coordinate system
(G92, G54 through G59) or local coordinate system (G52) cannot be
specified.
In the cylindrical interpolation mode, the cylindrical interpolation mode
cannot be reset. The cylindrical interpolation mode must be cancelled
before the cylindrical interpolation mode can be reset.
A tool offset must be specified before the cylindrical interpolation mode
is set. No offset can be changed in the cylindrical interpolation mode.
Cylindrical interpolation cannot be specified when the index table index
function is being used.
D Tool offset
D Cylindrical interpolation
accuracy
Limitations
D Arc radius specification
in the cylindrical
interpolation mode
D Circular interpolation
and cutter compensation
D Positioning
D Coordinate system
setting
D Cylindrical interpolation
mode setting
D Tool offset
D Index table indexing
function