YASKAWA yasnac lx3 - Page 128

2.8.26.2 Threading Cycle (G 92) (Cent’d)
The sign of figure following address I is de–
tided by the direction of position A’ viewed
from position B .
Since G92 is modal, the
cycle operation is continued by specifying
threading depth in the X-axis direction in
the trailing blocks as follows.
x(u) . . . ;
x(u) . . . ;
EXAMPLE :
N50 GOO X80. Z80.8 MOO ;
N51 G92 x70.
w-50.8 1-1.5 F2. ;
N52 x68.8 ;
N53 x67.8 ;
N54 GOO X1OO. Z1OO. MAA ;
m, ‘EAD20::\
!15
@711
‘-r
tz
Depth of Cut
Second cycle ::::
Th:,d cycle
(4) Taper threading cycle with angle (Cutting
along the angle of thread)
G92 X( U)... Z(W) . . . 1.. . K.. . F(E) ...;
This command permits the threading along
the angle of thread in taper threading. The
figure following the address K must be pro-
grammed with a sign.
.x
1 ,
z w
c
--. ——___
,...
I
g .
‘~
2 J
t
Fig. 2.61
Rapid traverse
Specfed by F code
(or E code)
z
c.
~ .-—-. —— ---
-+
i
{’fI-7
OF
Fig.
2.62
For the threading along the angle of thread,
the K for each cycle obtained from the fol-
lowing formula should be programmed.
I
1
IKn{ =
dn. tan(a/2)
It
~ .tan(a/2)
The sign in the denominator depends on 0 ‘ :
et < 900 ~ 11+11
e!
> 900 ~
II _ 1!
Note : For the control equipped with Mul-
tiple Repetitive Cycle~, the above trouble-
some calculation can be omitted by using
G76 (Automatic Thread Cutting Cycle) .
The control performs the above calculation
automatically by the G 76 command.
(5)
a.
b.
c.
Cautions in programming G 92
T, S and M functions for G92 cycle must be
specified as a rule beforehand in the preced-
ing blocks.
T, S and M blocks without move
commands are effective in the effective area
of G92.
ln
Single Block mode, the execution of G92
cycle is stopped after the completion of the
cycle @ to @ .
Thread cutting hold (option)
When this option is used, depressing the
FEED HOLD during thread cutting causes the
tool to perform threading up immediately and
then return to start point A.
When parameter #6019D7 = 1, the tool stops
at position B where threading up terminated.
Depressing the CYCLE START at start point
A or B restarts the current processing from
the beginning.
THREADCUTTING CYCLE
PATH WITHOUT HOLD
SWT
POINT
FEED HCLC
Fig. 2.63
120