HEIDENHAIN TNC 426, User Manual

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HEIDENHAIN TNC 426, TNC 430 279
8.5 Cy
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CIRCULAR PATTERN (Cycle 220)
1 At rapid traverse, the TNC moves the tool from its current position
to the starting point for the first machining operation.
Sequence:
n
Move to 2nd set-up clearance (spindle axis)
n
Approach the starting point in the spindle axis
n
Move to set-up clearance above the workpiece surface (spindle
axis)
2 From this position, the TNC executes the last defined fixed cycle.
3 The tool then approaches the starting point for the next machining
operation on a straight line at set-up clearance (or 2nd set-up
clearance).
4 This process (1 to 3) is repeated until all machining operations have
been executed.
U
Center in 1st axis Q216 (absolute value): Center of
the pitch circle in the reference axis of the working
plane
U
Center in 2nd axis Q217 (absolute value): Center of
the pitch circle in the minor axis of the working plane
U
Pitch circle diameter Q244: Diameter of the pitch
circle
U
Starting angle Q245 (absolute value): Angle
between the reference axis of the working plane and
the starting point for the first machining operation on
the pitch circle
U
Stopping angle Q246 (absolute value): Angle
between the reference axis of the working plane and
the starting point for the last machining operation on
the pitch circle (does not apply to complete circles).
Do not enter the same value for the stopping angle
and starting angle. If you enter the stopping angle
greater than the starting angle, machining will be
carried out counterclockwise; otherwise, machining
will be clockwise.
Example: NC blocks
53 CYCL DEF 220 POLAR PATTERN
Q216=+50 ;CENTER IN 1ST AXIS
Q217=+50 ;CENTER IN 2ND AXIS
Q244=80 ;PITCH CIRCLE DIAMETR
Q245=+0 ;STARTING ANGLE
Q246=+360 ;STOPPING ANGLE
Q247=+0 ;STEPPING ANGLE
Q241=8 ;NR OF REPETITIONS
Q200=2 ;SET-UP CLEARANCE
Q203=+30 ;SURFACE COORDINATE
Q204=50 ;2ND SET-UP CLEARANCE
Q301=1 ;TRAVERSE TO CLEARANCE HEIGHT
X
Y
Q217
Q216
Q247
Q245
Q244
Q246
N = Q241
X
Z
Q200
Q203
Q204
Before programming, note the following:
Cycle 220 is DEF active, which means that Cycle 220
automatically calls the last defined fixed cycle.
If you combine Cycle 220 with one of the fixed cycles 200
to 208, 212 to 215, 262 to 265 or 267, the set-up
clearance, workpiece surface and 2nd set-up clearance
that you defined in Cycle 220 will be effective for the
selected fixed cycle.