
1.
JNTRODUCTION
(a) Reference point (fixed position on machine)
A CNC machine tool is provided with a fixed position. Normally, tool change
and programming of absolute zero point as described later are performed at this
position. This position is called the reference point.
Reference point
Q- /
The tool can be moved to the reference point in two ways:
(i) Manual reference point return
Reference point return is performed by manual button operation.
(ii) Automatic reference point return (See I -6.1)
In general, manual reference point return is performed first after the power
is turned on. In order to move the tool to the reference point for tool change
thereafter, the function of automatic reference point return is used.
(b) Absolute coordinate values
The tool moves to a point at
“the distance from zero point of the coordinate
system,” i.e. to the position of
the coordinate values.
X
I
Specify the tool movement from point A to point B by using the coordinate
values of point B as follows:
G9OX25.OYI 0.0;
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