Siemens sinumerik 840d Programming Manual page 305

08.97
9
840D
NCU 572
NCU 573
Insert intermediate block at contour corners,
TLIFT
At one corner of the contour the tangent changes
and thus the setpoint position of the following axis.
The axis normally tries to compensate this step
change at its maximum possible velocity. However,
this causes a deviation from the desired tangential
position over a certain distance on the contour after
the corner. If such a deviation is unacceptable for
technological reasons, the instruction TILIFT can be
used to force the control to stop at the corner and to
turn the following axis to the new tangent direction in
an automatically generated intermediate block. The
axis is rotated at its maximum possible velocity.
The TLIFT(...) instruction must be programmed
immediately after the axis assignment with
TANG(...).
Example:
TANG(C,X,Y...)
TLIFT(C)
Deactivate TLIFT
To deactivate TLIFT, repeat the axis assignment
TANG(...) without inserting TLIFT(...) afterwards.
The angular change limit at which an intermediate
block is automatically inserted is defined via
machine data
$MA_EPS_TLIFT_TANG_STEP.
 Siemens AG 2000. All rights reserved
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide Advanced (PGA) – 04.00 Edition
9.1 Tangential control TANG, TANGON, TANGOF
810D 840Di
Path Traversing Behavior
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