Siemens SINUMERIK 840Di Function Manual page 833

TOROT or TOFRAME, etc., are disabled with language command TOROTOF. TOROTOF deletes
the entire system frame $P_TOOLFR. If the programmable frame (old variant) and not the
system frame is described by commands TOFRAME, etc., TOROT only deletes the rotation
component and leaves the remaining frame components unchanged.
If a rotating frame is already active before language command TOFRAME or TOROT is
activated, a request is often made that the newly defined frame should deviate as little as
possible from the old frame. This is the case, for example, if a frame definition needs to be
modified slightly because the tool orientation cannot be set freely on account of Hirthtoothed
rotary axes. The language commands uniquely define the Z direction of the new frame.
In previous software versions, machine data
MD21110 $MC_X_AXIS_IN_OLD_X_Z_PLANE
can be used to choose between two variants for the position of the X-axis and Y-axis.
However, in both cases there is no reference to the previously active frame.
Setting data
SD42980 $SC_TOFRAME_MODE
is, therefore, introduced, which can be used to control the response of TOFRAME and TOROT.
It can accept values of 0 (inactive) to 3. If the value of the setting data is not zero, the effect
of machine data
MD21110 $MC_X_AXIS_IN_OLD_X_Z_PLANE is overwritten.
The values 1 to 3 have the following meanings:
1:
2:
3:
Characteristics and expansions:
Settings 1 and 2 are reached by rotating the coordinate system around the Z axis, starting
from any position on the X and Y axis, until the desired setting is reached. Setting 3 is
achieved by executing a rotation whose value is the exact mean of these two angles.
However, this only applies for the case that the old and new Z direction enclose an angle of
less than 90 degrees. With variant 1, both the old and new X axes form an angle of under
90 degrees, with variant 2 the same is true of the Y axis (the relevant axes point in
"approximately" the same direction). If the two Z directions form an angle of more than
90 degrees, however, the conditions of an angle < 90 degrees between the old and new
axes can no longer be met simultaneously for both X and Y. In this case, priority is given to
the X direction, i.e., a mean value is taken from the direction for 1 and the negative direction
for 2.
Axis Types, Coordinate Systems, Frames (K2)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
The new X direction is chosen to lie in the X-Z plane of the old coordinate system.
In this setting the angle difference between the old and new Y axis will be minimal.
The new Y direction is chosen to lie in the Y-Z plane of the old coordinate system.
In this setting the angle difference between the old and new Y axis will be minimal.
The value chosen is the mean value of the two settings, which would have been chosen with 1
and 2.
Detailed Description
2.4 Frames
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