
APPENDIX
B–63124EN/01
I. GLOSSARY
719
Term Description
External I/O device Device connected to the CNC to transfer programs and tool offset data with
the CNC.
External motion function Outputting a signal (external operation function signal) from the CNC each
time a block in a program finishes positioning, causing the machine to perform
a specific operation.
External workpiece origin offset value Offset value from the machine zero point used to offset the workpiece coordi-
nate system origin. There is only one external workpiece origin offset value,
common to all workpiece coordinate systems, while the workpiece origin off-
set value is provided for each individual workpiece coordinate system.
[F]
F code Coded number, following the F address, that specifies a feedrate or an
amount of feed relative to a workpiece.
Feed function Controlling the tool feedrate.
Feed hold Temporarily stopping feed during program execution.
Feed per minute Cutting feed in which the distance the tool is to advance is specified per min-
ute.
Feed per revolution Cutting feed in which the distance the tool is to advance is specified per
spindle rotation.
Feedrate clamp based on arc radius Automatically clamping a circular cutting feedrate so that an arc radius error
due to post–interpolation acceleration/deceleration and servo delay does not
exceed an allowable error.
Figure copy Repetitive machining performed by rotating a figure specified by a subpro-
gram, or shifting it in parallel.
File Named set that is stored or processed as a single unit.
File heading Specifying a file that is to be manipulated (for example, to be input to the
CNC).
Floating reference position return Returning a tool to a floating reference position. The floating reference posi-
tion serves as a reference position for a specified mechanical operation. It is
not necessarily a fixed position. It may be relocated.
Forbidden area Area where a tool is forbidden to enter.
Format guidance Displaying program creation guidance in a specified format on the screen.
Function for switching between diameter
and radius programming
Preparatory function for switching between diameter and radius specifica-
tions.
Function key Key on the MDI keyboard used to select a screen to be displayed on the CNC
display unit. Function keys are classified by function.
[G]
G code Code that represents a preparatory instruction. A number that allows the G
address.
G function Command that determines a machine and/or CNC function mode, such as
interpolation type , canned cycle, threading, and coordinate system selection.
Geometric offset value That part of a tool offset value which compensates for the geometry of the
tool.
Graphic function Drawing the trajectory of a tool, being driven by the current machining pro-
gram, on the CNC screen.