HEIDENHAIN TNC 620 User Manual page 460

12
Programming: Multi-Axis Machining
12.5 FUNCTION TCPM
Type of interpolation between the starting and end
position
The TNC provides two functions for defining the type of
interpolation between the starting and end position:
PATHCTRL AXIS determines that the tool tip
is moving in a straight line between the start
and end position of the relevant NC block
(face
the starting and end position corresponds to
the programmed values in question; the tool
scope, however, does not describe a defined
path between the starting and end position.
The surface produced by milling with the tool
circumference
the machine geometry
PATHCTRL VECTOR determines that the tool
tip between the starting and end positions of
the respective NC block moves on a straight
line and also that the direction of the tool axis
between starting and end position is interpolated
so that a plane results from machining at the tool
circumference
With PATHCTRL VECTOR, remember:
Any defined tool orientation is generally accessible
through two different tilting angle positions. The TNC
uses the solution over the shortest available path—
starting from the current position.
To attain the most continuous multi-axis movement
possible, Cycle 32 should be defined with a
tolerance for rotary axes.
Further information: Cycle Programming User's
Manual
The tolerance of the rotary axes should be about the
same as the tolerance of the contouring deviation
that is also defined in Cycle 32. The greater the
tolerance for the rotary axes is defined, the greater
the contour deviations that occur during peripheral
milling.
Example NC blocks
...
13 FUNCTION TCPM F TCP AXIS SPAT PATHCTRL AXIS
14 FUNCTION TCPM F TCP AXIS POS PATHCTRL VECTOR
...
460
milling). The direction of the tool axis at
(peripheral milling) depends on
(peripheral milling)
HEIDENHAIN | TNC 620 | Conversational Programming User's Manual | 10/2015
Tool tip moves along a straight line
Tool tip and tool directional vector move in one plane