Block One of the command units constituting a program.
Block restart Resuming automatic operation from the start, or an intermediate point, of a
block if automatic operation has been interrupted in that block due, for exam-
ple, to tool breakage.
Buffering Standby state set up before a command is executed.
C–axis control Controlling a tool angle using a C command.
C–axis synchronous control Using two motors to synchronously control the punch and die of a tool under
Calling a subprogram stored in external
Calling and executing a subprogram from an external input/output device
such as a floppy cassette or program File Mate during memory operation.
Canned cycle Set of predefined sequences prepared for boring, drilling, and/or tapping.
Chamfering Obliquely cutting an inner or outer corner of a workpiece.
Changing workpiece coordinate system Relocating the origin of a workpiece coordinate system.
Chopping function Grinding the side surface of a workpiece by executing a contour program for
an axis other than the grinding axis while constantly moving the grinding axis
back and forth.
Chuck and tail stock barrier Checking for interference between the chuck, tail stock, and tool to prevent
damage to the machine.
Circle cutting function Simplified machining method for producing a true circle by moving a tool
along the circumference of a target circle from the center of the circle.
Circular interpolation Obtaining a path necessary to move the tool along an arc in a specified plane.
Circular threading Combination of two–axis circular interpolation and linear interpolation for up to
two axes, one of which is the major axis in circular interpolation while the
other is any axis. Circular threading can be used for constant–pitch thread-
ing, grooving, and tool grinding on a barrel–shaped surface.
Clamp of maximum spindle speed Specifying a rotation speed per minute as the maximum spindle speed during
constant surface speed control.
Cleared state Initially specified device state.
Command format Array of program component enabling direct manipulation of the CNC.
Comment section Information such as comments and directions output to the operator.
Common variable Macro variable that can be used by two or more different custom macro pro-
Compensating backlash along C–axis
for each tool group
Compensating the position of tools that can be controlled using the C–axis for
Compensating position of C–axis Correcting mechanical error when a tool that can be controlled using the
C–axis is mounted.
Compensation function Generic term applied to tool path, backlash, and pitch error compensation.
Composite control (Two– path control
Two–path control in which a move command for an axis in one of the paths is
exchanged with a move command for an axis in the other path.
Conical interpolation Obtaining a conical path by adding a one–axis movement command to a spi-
ral interpolation command to specify an increment/decrement per spiral turn
for the added axis.
Constant surface speed control Controlling the spindle speed during turning so that the cutting feedrate
remains constant despite changes in the target radius.