Chapter 7 Appendix 7.1 Work and Tool Coordinate System Features for Linear Axis
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Also, when a work piece is mounted on an axis of either X, Y or Z-axis, the positive side of the
base coordinate system is the opposite direction of the operation direction of the physical axis.
For instance, in below explains for when a work piece is mounted on the X-axis in TTA-A4 (XYZ
Home Standard Specification).
In this case, if moving the X-axis in the positive direction of each axis system, the tool attachment
datum point seems to move in opposite direction to the motion if viewed from the work piece.
Therefore, the base coordinate system is shown as the figure below.
In below, shows the definition related to the home of the base coordinate system and the direction
of coordinates.
Home : The position of the tool attachment datum point under
condition that each axis system coordinates for all the unit
constructing axes = 0
Positive direction of coordinate : The direction that the tool attachment datum point moves to
the work piece mount face when each axis in the each axis
system is moved in the positive direction