Siemens SINUMERIK 840D Operator's Manual page 480

A
Appendix
B Terms
Electronic handwheel
Exact stop
Exact stop limit
External zero offset
F
Fast retraction from
contour
Feedforward control,
dynamic
Feedrate override
Finished-part contour
Fixed machine point
Fixed-point approach
A-480
Electronic handwheels can be used to traverse the selected axes
simultaneously in manual mode. The handwheel clicks are analyzed
by the increment analyzer.
When an exact stop is programmed, a position specified in the block
is approached accurately and, where appropriate, very slowly. In
order to reduce the approach time, -> exact stop limits are defined for
rapid traverse and feed.
When all path axes reach their exact stop limits, the control responds
as if it had reached its destination point precisely. The -> parts
program continues execution at the next block.
A zero offset specified by the -> PLC.
When an interrupt is received, it is possible to initiate a motion via the
CNC machining program which allows the tool to be retracted quickly
from the workpiece contour currently being machined. The retraction
angle and the distance retracted can also be parameterized. An
interrupt routine can be executed after the rapid retraction.
(SINUMERIK FM-NC, 840D).
Contour inaccuracies resulting from following errors can be almost
completely eliminated by the dynamic, acceleration-dependent
feedforward control function. Feedforward control ensures an
excellent degree of machining accuracy even at high tool path
velocities.
Feedforward control can only be selected or deselected for all axes
together via the parts program.
The current feedrate setting entered via the control panel or by the
PLC is overlaid on the programmed feedrate (0–200%). The feedrate
can also be corrected by a programmable percentage factor (1–
200%) in the machining program.
Contour of the finished workpiece. See also -> blank.
A point defined uniquely by the machine tool, such as the reference
point.
Machine tools can execute defined approaches to fixed points such as
tool-change points, loading points, pallet-change points, etc. The
coordinates of these points are stored on the control. Where possible,
the control moves these axes in -> rapid traverse.
SINUMERIK 840D/840Di/810D Operator's Guide HMI Advanced (BAD) – 03.04 Edition
A
03.04
Ó Siemens AG, 2004. All rights reserved