
APPENDIX
B–64154EN/01
H. GLOSSARY
681
Term Description
Incremental feed Feeding a controlled axis by a preset amount each time the corresponding
button is pressed.
Incremental programming Method by which an amount of tool movement (relative to the previous tool
position) is programmed.
Incremental value Distance or angle relative to the previous position.
Index table indexing function Indexing on the index table of a machining center.
Initial position Level in a hole axial direction to which positioning is performed for the first
time during a canned hole machining cycle. Succeeding drills return to the R
Plane.
Input buffer Area into which input data is temporarily saved.
Interference check Preventing a tool from overcutting the workpiece or from striking the tool on
the other tool post.
Interlock Preventing the movement of a controlled axis. This function is enabled by
supplying an interlock signal to the CNC.
Internal circular cutting feedrate change Controlling circular cutting so that the feedrate for a programmed path
matches the specified cutting feedrate when the actual tool path is offset
within the programmed tool path.
Interpolation functions Obtaining a tool path according to a function (such as a linear or arc function)
corresponding to a specified preparatory function.
Interruption type custom macro Calling a program to be executed by entering an interrupt signal to the CNC
during the execution of another program.
Inverse time feed Cutting feed for which the reciprocal of the time required to feed the tool is
specified.
Involute interpolation Determining the path necessary to move the tool along an involute curve in a
specified plane.
ISO code Information exchange code complying with the applicable ISO standard.
Used in numerical control.
[J]
Jog feed Manually feeding a specified controlled axis at a specified feedrate.
Jog feedrate override Manual control in which the operator can change the jog feedrate.
[L]
Lag of servo system State in which the feed axis of a machine lags behind the corresponding feed
command.
LCD/MDI Panel which incorporates both a liquid crystal display (LCD) panel and a
manual data input (MDI) keyboard. Used to display and set programs and
data in the CNC.
Leader section Program component used as a program file header.
Leading edge compensation Offsetting a tool path by the tool radius so that the tool edge coincides with a
programmed path if the tool (tool axis) is oriented in an arbitrary direction in
three–dimensional space.
Least command increment The smallest unit of controlled axis movement that can be specified by the
CNC or PMC.
Least input increment The smallest unit of data that can be input to a program.