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A- 77987EN
DRAW.No.
FANUC Series 16
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Specifications of Distance Coded Linear
Scale Interface Ex
ansion
Title
Newly Registered
DESCRIPTIONDESIGNE
99.12.03
DATE
01
EDIT.
(2) When an Incremental command is specified
Each axis moves only by the commanded distance. That is, the behavior of the axis is
shown on a bold line in the figure below. However, the figure shows each position, and it
does not show an actual tool path.
The coordinate value of the end point becomes the value in newly established coordinate
system. That is, the coordinate value of the end point shifts by the difference (a,b) if there
is the difference (a,b) between a newly established coordinates system and old one.
For instance, when "G91 G00 X100.Y30; (M system)" or "G00 W100.U30; (T system)" is
commanded at the position of (0,0), the movement amount of each axis becomes (100,30)
and the coordinates value of end point becomes (100-a, 30-b).
2.1.2.3 Short distance movement
The axis reaches the end point before passing 3 or 4 reference marks when the specified
distance is too short. For this case, the axis moves at the FL speed to detect the reference
marks, but reference point is not established because CNC cannot detect enough reference
marks.
When the reference point is not established, the reference point establishment operation is
executed again by the next G00 command. Information of the reference marks detected in
the last establishment operation is not used at this time, and the reference point is
established by detecting 3 or 4 reference marks again.
Fig.6 Operation of incremental command
SP : Start point
EP
: Actual end point ((100-a,30-b) in new coordinate system)
EP’ : End point when G00 is commanded((100,30) in old coordinate system)
(a,b) : Difference between coordinate systems before and after the reference point establishment
A : The point where the reference points are established
B : (100,30) in new coordinate system
ZOFS : Workpiece zero point offset value
A
SP
Old machine coordinate system
•
not exact
•
ZOFS
B (100,30)
New workpiece coordinate system
•
exact
•
New machine coordinate system
•
exact
•
Old workpiece coordinate system
•
not exact
•
EP’ (100,30) = EP (100-a,30-b)
ZOFS
(a,b)