
B–63522EN/02
14. TOOL COMPENSATION FUNCTION
NC FUNCTION
217
On a five–axis machine having two rotation axes that turn a tool, tool
length compensation can be performed momentarily even in the middle
of a block.
Tool length compensation is classified into two types according to the
programming method. In the explanation of this function, the two
rotation axes are assumed to be the B– and C–axes.
(1) Type 1
The rotation axis position (B, C) is specified.
The CNC applies tool length compensation equal to the compensation
amount along the tool axis whose orientation is calculated from the
specified rotation axis position. This means that compensation is
performed by moving the three linear axes.
(2) Type 2
The tool axis orientation (I, J, K) is specified.
The CNC controls the two rotation axes so that the tool is oriented as
specified, and performs tool length compensation along the tool axis
by the compensation amount. This means that compensation is
performed by moving the two rotation axes and three linear axes.
Tool center point control (type 1) differs from tool length compensation
along the tool axis as shown below:
Tool center point control (type 1)
The path of the tool tip center is linear as specified.
Tool length compensation along the tool axis
The path of the tool tip center is not linear.
Tool pivot point
= interpolation path
(not linear)
Tool tip center path
(linear)
Tool pivot point
= interpolation path
(linear)
Tool tip center path
(not linear)
Fig. 14.16 Difference between tool center point control and tool length
compensation along the tool axis
NOTE
The length from the tool tip to tool pivot point must equal the
sum of the tool length compensation amount and tool holder
offset value.
14.16
TOOL CENTER POINT
CONTROL