Fourth Axis - Siemens SINUMERIK 802D sl Programming And Operating Manual

Programming
10.3 Axis movements
10.3.13

Fourth axis

Functionality
Depending on the machine variant, a fourth axis may be necessary, e.g. dividing unit,
swiveling dresser, head dresser, etc. This axis can take the form of either a linear or a rotary
axis. The designation of this axis must be configured accordingly, e.g. U, C, or A etc. For
rotary axes, the traversing range can be configured between 0 ...360 degrees (modulo-
behavior).
With an appropriate machine design, the fourth axis can be traversed linear simultaneously
with the remaining axes. If the axis is traversed together with the remaining axes (X, Z) in a
block that contains G1 or G2/G3, no component of the feedrate F is assigned to this axis; its
velocity will depend on the time for traveling along the X and Z axes, and its motion starts
and ends with the remaining path axes. The velocity, however, must not be greater than the
defined limit value.
If in one block only this fourth axis is programmed, the axis will traverse using the active
feedrate F if G1 is active. If the axis is a rotary axis, the unit for F is degrees/min with G94 or
degrees/rev. of the spindle with G95.
For this axis, it is also possible to specify (G54 ... G59) and program (TRANS, ATRANS)
offsets.
Programming example
The fourth axis is a swivel table (rotary axis) and has the axis identifier A:
N5 G94
N10 G0 X10 Y20 Z30 A45
N20 G1 X12 Y21 Z33 A60 F400
N30 G1 A90 F3000
Special instructions for rotary axes: DC, ACP, ACN
For example, for rotary axis A:
A=DC(...)
A=ACP(...)
A=ACN(...)
Example:
N10 A=ACP(55.7)
246
; Feedrate F in mm/min or degrees/min
; Traverse X-Y-Z path with rapid traverse, A at the
same time
; Traverse X-Y-Z path at 400 mm/min, A at the same
time
; Axis A traverses alone to position 90 degrees at a
speed of 3000 degrees/min
; Absolute dimensions, approach position directly (on the
shortest path)
; Absolute dimensions, approach position in positive direction
; Absolute dimensions, approach position in negative direction
; Approach absolute position 55.7 degrees in positive direction
Programming and Operating Manual, 11/2012, 6FC5398-5CP10-3BA0
Surface grinding