Siemens SINUMERIK 840D sl Function Manual page 124

W1: Tool offset
2.8 Tool carriers with orientation capability
Activation of kinematic types P and M
With kinematics of type P and M the selection of a toolholder activates an additive frame (table
offset of the toolholder with orientation capability), which takes into account the zero point offset
as a result of the rotation of the table.
The zero offset can be written to a dedicated system frame $P_PARTFR. For this, the bit 2 must
be set in the machine data:
MD28082 $MC_MM_SYSTEM_FRAME_MASK (system frames (SRAM))
The basic frame identified by following machine data is then no longer required for the zero
offset:
MD20184 $MC_TOCARR_BASE_FRAME_NUMBER (number of the basic frames for taking
the table offset)
Activation of kinematic type M
With kinematics of type M (tool and table are each rotary around one axis), the activation of a
toolholder with TCARR simultaneously produces a corresponding change in the effective tool
length (if a tool is active) and the work offset.
Rotations
Depending on the machining task, it is necessary to take into account not only a work offset
(whether as frame or as tool length) when using a rotary toolholder or table, but also a rotation.
However, the activation of an orientable toolholder never leads directly to a rotation of the
coordinate system.
TOROT
If only the tool can be rotated, a frame whose Z axis points in the direction of the tool can be
defined with TOFRAME or TOROT.
PAROT
If the coordinate system needs to be fixed relative to the workpiece, i.e. not only offset relative
to the original position but also rotated according to the rotation of the table, then PAROT can be
used to activate such a rotation in a similar manner to the situation with a rotary tool.
With PAROT, the translations, scalings and mirrorings in the active frame are retained, but the
rotation component is rotated by the rotation component of a toolholder with orientation
capability corresponding to the table.
PAROT and TOROT take into account the overall change in orientation in cases where the table
or the tool are oriented with two rotary axes. With mixed kinematics, only the corresponding
component caused by a rotary axis is considered. It is thus possible, for example, when using
TOROT, to rotate a workpiece such that an oblique plane lies parallel to the XY plane fixed in
space, whereby rotation of the tool must be taken into account in machining where any holes
to be drilled, for example, are not perpendicular to this plane.
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Function Manual, 06/2019, A5E47435126B AA
Tools