Siemens SINUMERIK 840D sl Function Manual page 128

W1: Tool offset
2.8 Tool carriers with orientation capability
Tool radius compensation with CUT2D or CUT3DFS:
The current tool orientation is included in the tool radius compensation if either CUT2D or
CUT3DFS is active in G group 22 (tool offset type).
For nonrotating tool carriers, the behavior depends solely on the active plane of the G
command of group 6 (G17 - G19) and is, therefore, identical to the previous behavior.
All other tool offset types:
The behavior for all other tool offset types is unchanged.
For CUT2DF and CUT3DFF in particular, the compensation plane used for TRC is determined
from the active frame, independent of the current tool orientation. Allowance is made for the
active plane (G17 - G19) and the behavior is, therefore, the same as before.
The two remaining G commands of group 22, CUT3DC and CUT3DF, are not affected by the tool
carrier functionality because the tool orientation information in these cases is made available
by the active kinematic transformation.
Two rotary axes
Two general solutions exist for two rotary axes. The control itself chooses these two solution
pairs such that the orientation angles resulting from the frame are as close as possible to the
specified angles.
The two following options are available for specifying the angles:
1. If $TC_CARR21 or $TC_CARR22 contains a reference to a rotary axis, the position of this
axis at the start of the block in which the tool carrier is activated is used to specify the angle.
2. If $TC_CARR21 or $TC_CARR22 does not contain a reference to a rotary axis, the values
contained in $TC_CARR13 or $TC_CARR14 are used.
Example
The control first calculates an angle of 10 degrees for one axis. The specified angle is 750
degrees. 720 degrees (= 2 * 360 degrees) are then added to the initial angle, resulting in a final
angle of 730 degrees.
Rotary axis offset
Rotary axis offsets can be specified with system variables $TC_CARR24 and $TC_CARR25.
A value not equal to zero in one of these parameters means that the initial state of the
associated rotary axis is the position specified by the parameter (and not position zero). All
angle specifications then refer to the coordinate system displaced by this value.
When the machining plane is changed (G17 - G19), only the tool length components of the
active tool are interchanged. The components of the tool carrier are not interchanged. The
resulting tool length vector is then rotated in accordance with the current tool carrier and, if
necessary, modified by the offsets belonging to the tool carrier.
The two tool carrier angles α
plane currently selected (G17 - G19).
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and α are determined using a frame, independent of the active
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Function Manual, 06/2019, A5E47435126B AA
Tools