TC-32B Chapter 5 Preparation function (canned cycle)
2004/01/22 5 - 29 eTCOMNCPR5-1.doc
5
(4) Reverse tapping cycle (synchro mode)(G78) (Reducing step)
I_
Command format G78 X _ Y _ Z _ R_ W _ V _ S _ ;
J_
W : 1st cutting feed
V : Minimum cutting feed
eNCPR5.29.ai
• The relief amount d is set by the parameter 1.
•
If a negative value is entered for the cutting amount V and W, the algebraic symbol (-) is
ignored.
•
When a temporary stop is applied on the way from the R point to the Z point or the R point,
the tool stops after returning to the R point.
•
A thread pitch or number of threads should be specified.
•
Set the data on a thread pitch following the address I, and the data on a number of threads
following the address J.
•
If the address S exceeds the max, spindle speed in tapping, an alarm is generated.
Rapid feed
Cutting feed
Spindle CW
Spindle CCW
R point
Z point
d
d
d
Return point
W
Spindle
stop
.
.
.
V
3rd cuttin
feed
2nd cutting feed