HEIDENHAIN TNC 620 (73498x-01) ISO programming - Manual (Page 333)

HEIDENHAIN TNC 620 333
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.4 Miscellaneous functions f
o
r r
o
tary ax
es
Maintaining the position of the tool tip when
positioning with tilted axes (TCPM): M128
(software option 2)
Standard behavior
The TNC moves the tool to the positions given in the part program. If
the position of a tilted axis changes in the program, the resulting offset
in the linear axes must be calculated, and traversed in a positioning
block.
Behavior with M128 (TCPM: Tool Center Point Management)
If the position of a controlled tilted axis changes in the program, the
position of the tool tip to the workpiece remains the same.
After M128 you can program another feed rate, at which the TNC will
carry out the compensation movements in the linear axes.
M128 on tilting tables
If you program a tilting table movement while M128 is active, the TNC
rotates the coordinate system accordingly. If, for example, you rotate
the C axis by 90° (through a positioning command or datum shift) and
then program a movement in the X axis, the TNC executes the
movement in the machine axis Y.
The TNC also transforms the defined datum, which has been shifted
by the movement of the rotary table.
The machine geometry must be specified by the machine
tool builder in the description of kinematics.
X
Z
B
Z
X
Caution: Danger to the workpiece!
For tilted axes with Hirth coupling: Do not change the
position of the tilted axis until after retracting the tool.
Otherwise you might damage the contour when
disengaging from the coupling.
Before positioning with M91 or M92 and before a block,
RESET M128
.
The tool length must refer to the spherical center of the
tool tip.
If M128 is active, the TNC shows the symbol TCPM in the
status display.