
15. ACCURACY COMPENSATION
FUNCTION B–63522EN/02
NC FUNCTION
222
When a pitch error of a feed screw has a constant slope, you only need to
select four representative points (a, b, c, d) from pitch error compensation
points and set slope data for the four points; unlike pitch error
compensation, you need not set compensation data for every
compensation point. Then, compensation data at each compensation
point is calculated automatically for compensation. (When movement
along an axis for which slope compensation data is set is made,
compensation is performed for that axis.)
Pitch error compensation is required to use this function.
b
a
c
d
On a machine having a long stroke, machining precision may be reduced
if the straightness of the axes is poor. The straightness compensation
function compensates an axis in detection units while the tool is moving
along another axis, thus improving machining precision.
Moving the tool along an axis (the movement axis, specified with a
parameter) compensates another axis (the compensation axis, specified
with a parameter) within the range for pitch error compensation for the
movement axis.
Pitch error compensation points along the movement axis
… …
Example:
0123 6061 126127
Machine coordinates along the movement axis
… …
ac
α
β
γ
bd
ε
a, b, c, d : Compensation point numbers for the movement axis (same as the numbers
of the pitch error compensation points)
α, β, γ, ε : Compensation value for each compensation point number (the amount of
compensation performed for the compensation axis)
The compensation value applied to the compensation axis is (β – α)/(a –
b) for the range between points a and b.
15.4
SLOPE
COMPENSATION
15.5
STRAIGHTNESS
COMPENSATION