
7.
COORDINATE SYSTEM
7.1 Machine Coordinate System
7
m COORDINATE
The function of the CNC is to move the machine, i.e. tool to a programmed position at
a programmed rate.
The position to be reached by the tool is given as a coordinate
value in a coordinate system.
The following two types of coordinate systems are available.
0
ii)
Machine coordinate system
Work coordinate system
The position to be reached by the tool is indicated with coordinates in one of the
coordinate systems.
Coordinates are specified with respect to the components on the program axes.
Specify coordinates as follows if the program axes are X and Y.
x Y
-w
Fig. 7 Position of Tool When the coordinates X4O.O,Y30.0 are specified
In this manual, coordinates
used depends on the model
7.1
Machine Coordinate System
7.1.1
are expressed as IP
-
the number of coordinates
The machine zero point is a standard point on the machine. The machine zero point is
normally determined by the machine tool builder.
A coordinate system having the zero point at the machine zero point is called the
machine coordinate system.
However, the zero point may be a point which the tool cannot reach.
The machine coordinate system is established when the reference point return is first
executed after the power is on.
Once the machine coordinate system is established, it is not changed by reset,
change of work coordinate system (G92) or other operations unless the power is
turned off.
Setting machine coordinate system
The machine coordinate system is inherent to each machine. The machine coordinate
system is established through manual return to the reference point.
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