Rounding In Compliance With Defined Tolerances (G642/G643) - Siemens SINUMERIK 840D sl Function Manual

B1: Continuous-path mode, Exact stop, Look Ahead
4.3 Continuous-path mode
Program example
Program code
N1 G641 Y50 F10 ADIS=0.5
N2 X50
N3 X50.7
N4 Y50.7
N5 Y51.4
N6 Y51.0
N7 X52.1
4.3.3.2

Rounding in compliance with defined tolerances (G642/G643)

Function
In continuous-path mode involving rounding in compliance with defined tolerances, the
rounding normally takes place while adhering to the maximum permissible path deviation.
Instead of these axis-specific tolerances, the maintenance of the maximum contour deviation
(contour tolerance) or the maximum angular deviation of the tool orientation (orientation
tolerance) can be configured.
Activation
Continuous-path mode with rounding in compliance with defined tolerances can be activated
in any NC part program block by the modal command G642 or G643.
Selecting the exact stop which works on a block-by-block basis enables rounding to be
interrupted (G9).
Continuous-path mode with rounding in compliance with defined tolerances (G642/G643) can
be deactivated by selecting:
● Modal exact stop (G60)
● Continuous-path mode G64, G641, G644 or G645
Differences between G642 - G643
With regard to their rounding behavior, commands G642 and G643 differ as follows:
G642
With G642, the rounding path is determined on the
basis of the shortest distance for rounding all axes.
This value is taken into account when generating
a rounding block.
With G642, the rounding area results from the
smallest tolerance setting.
192
Comment
; Continuous-path mode with rounding based on a path
criterion (rounding clearance: 0.5 mm)
G643
In the case of G643, each axis may have a differ‐
ent rounding path. The rounding travels are taken
into account axis-specifically and block-internally
(⇒ no separate rounding block).
Very different specifications for the contour toler‐
ance and the tolerance of the tool orientation can
only have effect with G643.
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions