Traversing In The Direction Of Tool Orientation (Movt) - Siemens SINUMERIK 840D sl Function Manual

For further information, see Function Manual "Basic Functions", Chapter "Axes, coordinate
systems, frames".
Boundary condition
If the behavior is set such that the offset remains active even after the end of the program
and RESET
MD20110 $MC_RESET_MODE_MASK, bit6=1 (specification of the controller initial setting
after reset / TP end)
and if an incremental path is programmed in the first part program block, the compensation is
always traversed additively to the programmed path.
Note
With this configuration, part programs must always begin with absolute programming.
2.10.2

Traversing in the direction of tool orientation (MOVT)

Typical application
On machines with toolholders with orientation capability, traversing should take place in the tool
direction (typically, when drilling) without activating a frame (e.g., using TOFRAME or TOROT), on
which one of the axes points in the direction of the tool.
This is also true of machines on which a frame defining the oblique plane is active during
oblique machining operations, but the tool cannot be set exactly perpendicular because an
indexed toolholder (Hirth tooth system) is restricting the setting of the tool orientation.
In these cases it is then necessary - contrary to the motion actually requested perpendicular to
the plane - to drill in the tool direction, as the drill would otherwise not be guided in the direction
of its longitudinal axis, which, among other things, would lead to breaking of the drill.
MOVT
The end point of such a motion is programmed with MOVT= .... The programmed value is
effective incrementally in the tool direction as standard. The positive direction is defined from
the tool tip to the toolholder. The content of MOVT is thus generally negative for the infeed
motion (when drilling), and positive for the retraction motion. This corresponds to the situation
with normal paraxial machining, e.g., with G91Z ....
If the motion is programmed in the form MOVT=AC( ...), MOVT functions absolutely. In this
case a plane is defined, which runs through the current zero point, and whose surface normal
vector is parallel to the tool orientation. MOVT then gives the position relative to this plane:
Tools
Function Manual, 06/2019, A5E47435126B AA
2.10 Incrementally programmed compensation values
W1: Tool offset
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