
6.INTERPOLATION FUNCTION B-63783EN-1/01
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If the difference between the radius at the start point and that at the end
point exceeds the permitted value in a parameter (No.2410), an P/S alarm
(No.191) occurs.
The distance between an arc and the center of a circle that contains the
arc can be specified using the radius, R, of the circle instead of I, J, and
K.
In this case, one arc is less than 180°, and the other is more than 180° are
considered. When an arc exceeding 180° is commanded, the radius must
be specified with a negative value. If Xp, Yp, and Zp are all omitted, if
the end point is located at the same position as the start point and when R
is used, an arc of 05 is programmed G02R ; (The cutter does not move.)
(Example)
For arc (1) (less than 180
°)
G91 G02 X60.0 Y20.0 R50.0 F300.0 :
For arc (2) (greater than 180°)
G91 G02 X60.0 Y20.0 R-50.0 F300.0 :
r =50mm
End point
Start point
r =50mm
Y
(1)
(2)
Fig.6.3 (c) Arc radius
The feedrate in circular interpolation is equal to the feed rate specified by
the F code, and the feedrate along the arc (the tangential feedrate of the
arc) is controlled to be the specified feedrate.
When an end point does not lie on the arc, a spiral results, as shown
below.