Feed rate for circular arcs: m109/m110/m111 – HEIDENHAIN TNC 620 (340 56x-03) User Manual
Page 315
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HEIDENHAIN TNC 620
315
9.4 Miscellaneous F
unctions f
o
r Cont
our
ing Beha
vior
Feed rate in millimeters per spindle revolution:
M136
Standard behavior
The TNC moves the tool at the programmed feed rate F in mm/min.
Behavior with M136
With M136, the TNC does not move the tool in mm/min, but rather at
the programmed feed rate F in millimeters per spindle revolution. If
you change the spindle speed by using the spindle override, the TNC
changes the feed rate accordingly.
Effect
M136 becomes effective at the start of block.
You can cancel M136 by programming M137.
Feed rate for circular arcs: M109/M110/M111
Standard behavior
The TNC applies the programmed feed rate to the path of the tool
center.
Behavior at circular arcs with M109
The TNC adjusts the feed rate for circular arcs at inside and outside
contours so that the feed rate at the tool cutting edge remains
constant.
Behavior at circular arcs with M110
The TNC keeps the feed rate constant for circular arcs at inside
contours only. At outside contours, the feed rate is not adjusted.
Effect
M109 and M110 become effective at the start of block. To cancel
M109 or M110, enter M111.
In inch-programs, M136 is not permitted in combination
with the new alternate feed rate FU.
The spindle is not permitted to be controlled when M136
is active.
If you define M109 or M110 before calling a machining
cycle with a number greater than 200, the adjusted feed
rate is also effective for circular arcs within these
machining cycles. The initial state is restored after
finishing or aborting a machining cycle.