4 miscellaneous functions for rotary axes – HEIDENHAIN TNC 640 (34059x-01) ISO programming User Manual
Page 343

HEIDENHAIN TNC 640
343
1
1
.4 Miscellaneous F
unctions f
o
r Rotary Ax
es
11.4 Miscellaneous Functions for
Rotary Axes
Feed rate in mm/min on rotary axes A, B, C:
M116 (software option 1)
Standard behavior
The TNC interprets the programmed feed rate of a rotary axis in
degrees/min (in mm programs and also in inch programs). The feed
rate therefore depends on the distance from the tool center to the
center of axis rotation.
The larger this distance becomes, the greater the contouring feed
rate.
Feed rate in mm/min on rotary axes with M116
The TNC interprets the programmed feed rate of a rotary axis in
degrees/min (or 1/10 inch/min). In this case, the TNC calculates the
feed for the block at the start of each block. With a rotary axis, the feed
rate is not changed during execution of the block even if the tool
moves toward the center of the rotary axis.
Effect
M116 is effective in the working plane. To reset M116, enter M117.
M116 is also canceled at the end of the program.
M116 becomes effective at the start of block.
The machine geometry must be specified by the machine
tool builder in the description of kinematics.
M116 works only on rotary tables. M116 cannot be used
with swivel heads. If your machine is equipped with a
table/head combination, the TNC ignores the swivel-head
rotary axes.
M116 is also effective in an active tilted working plane.