Nomenclature of NC machine axes:
International Standard
(ISO/R841) is followed for nomenclature of NC machine axes. US standard EIA
(Electronic Industries Association) documentation RS 267 is basis for ISO
standard. The guiding coordinate system
for designating the axes is conventional mathematical right-handed coordinate
system.
Machine Types:
Group I : Machine
tools with rotating tools:
Group
I (a): Vertical Spindle Rotating Tools
Spindle with cutting power.
Vertical Knee Mill
Drilling Machine
Profiling and Contour Mill
Vertical Boring Mill
Tapping Machine
Group
I (b): Horizontal Spindle Rotating Tools
Horizontal Boring Machine
Group II: Machine tools with rotating work pieces
Lathes
Group III:
Machine tools with non-rotating tools and non-rotating work piece.
Shaper, planner
Group (IV) NC Drafting Machine
First of all Z-motion shall be designated; secondly X
and thirdly Y. Z axis is along spindle axis or parallel to spindle axis. For
group III and Group IV machines Z-axis is perpendicular to work holding surface.
Motion of tool towards work shall be considered
to occur in negative (- Z) direction and moving of the tool away from work shall
be considered to occur in positive (+) Z direction. Motion in positive (+Z)
direction increases the clearance between work surface and tool holder. X and
Y-axes are determined with reference to Z-axis.
