Programming instructions

4-12
Motion Blocks NC Programming 17VRS
DOK-MTC200-NC**PRO*V17-ANW1-EN-P
Block Transition with Lag Present 'G62'
With interpolation condition G62 processing switches to the next NC-
block as soon as the command values for all axes programmed in the
NC-block that are issued by the interpolator have reached their pro-
grammed final values. The system does not wait until the actual values
have reached their final position. Any lag (following error) which may be
present is not reduced as the final position is approached.
•
G62 NC-block transition with lag present is suppressed when G00
linear interpolation at rapid traverse is programmed.
•
Sudden contour changes and non-tangential transitions are rounded
off by programming G62.
•
G62 is the power-on default. It is active and latched until it is overwrit-
ten by a G61. G62 is reset automatically at the end of the program
(RET) or by the BST, M02, M30 command.
•
Machining time is reduced when G62 and G08 are programmed.
Examples
Test Contour : Transition Circle -> Circle Not Tangential , Circle ->
Tangential
Feedrate:
F4000
G06 , G62
Gain = 7
Transition St. Line -> Circle
Not Tangential
Transition Circle -> Circle
Tangential
Position Difference
in Transition
St. Line -> Circle
Oscilloscope Function
Position Values Y Axis [mm]
Position Difference:
Position Command Value:
Expansion Factor: 2444.6
Position Values X Axis [mm]
Fig. 4-16: Contour diagram with G62
The contour diagram shown here (Fig. 4-16) illustrates how the non-tan-
gential transitions (straight line
→
circle) are slurred as a consequence of
G62. The contour is traversed at optimal velocity (via G08). At the contour
itself, the machining quality is identical to that achieved with G61. When
one compares the contour diagrams in Figs. 4-14 (G61) and 4-16 (G62),
one sees that the expansion factor for the position deviation is four times
as high in Fig. 4-16.
Example of a program for the diagrams shown in Figs. 4-16 and 4-17:
G00 G54 G90 G06 G08 X-100 Y-100 Starting point
G01 G62 X-50 Y-50 F4000 1st straight line
G02 X50 Y-50 I0 J-50 1st semicircle
G03 X100 Y-50 I75 J-50 2nd semicircle
RET Return to program beginning
In the following velocity diagram (Fig. 4-17), one can see how the path
velocity in the non-tangential transition straight line
→
circle is reduced by
the change of direction. The tangential transition circle
→
circle is trav-
ersed at a constant path velocity as a consequence of conditions G62 and
G08.