YASKAWA yasnac lx3 - Page 51

2.8.17 VARIABLE LEAD THREAD CUTTING+
(1)
(2)
a.
b.
c.
d.
G34 X( U)... z(w) . . . K.. F(E) -$” ;
With this command, variable lead screws are
controlled with the increase or decrease of
lead per revolution specified by address K.
VARIABLE LEAD SCREW
Fig. 2.23
Variable Lead Threadcutting
The range of K programmable for variable
lead screws is as follows.
Least input increment:
0.0001 mm/rev.
0.000001 in./rev.
(Metric Input)
(Inch Input)
Programmable range:
The highest feedrate is within the maximum
programmable feedrate range ( 500 mm/rev
(metric) or 50 in/rev. (inch))
The total displacement resulting from changes
in lead is within the following.
4194.303 mm (metric output)
419.4303 in.
(inch output)
Feedrate change corresponding to lead
variation must not exceed 5, 400 mm /rein
(metric output) or 540 inJmm (inch output).
Lead value should not be minus value.
Notes :
1.
2.
3.
4.
5.
When variable lead threads are cut by continu-
ous block programs, command pulses are
interrupt ed at block junctions.
If K commands exceed the permissible range,
alarm (1060!!” will be displayed.
When G 34 command is executed in the Dry
Run mode, the tool moves only at the speed
specified by the manual continuous feedrate
command, if parameter SCRDRN ( #6019 BIT5)
is set to 1.
When parameter
!11oIN!! ( #6006D5) is set to
1, least increment for K commands is 0.001
mm/rev or O. 0001 in./rev.
Commanding address B in G34 block causes
alarm 11(360.II
(3) Confirmation calculation for K command of
variable lead thread cutting.
a. K command is restricted in the following
conditions.
(i)
(ii)
(iii)
(iv)
Feedrate at end point must not exceed
programmable range.
500 mrfl/rev (metric output) or 50 in
rev (inch output)
Feedrate at end point must not be minus
value.
Accumulated value of movement due to
lead variation must not exceed 4194.303
mm (metric output) or 419.4303 in (inch
output) .
Feedrate change corres~ondin~ to lead
variation must not exceed 5, 400 mm /rein
(metric output) or 540 in /mm (inch output
b. The control checks the restriction described
above using the following equation.
F:
K:
w:
s:
N:
(i)
(ii)
(iii)
(iv)
Fixed lead command (mm /rev or in,f
rev)
Variable lead command (mm/rev or
in./ rev )
Distance between start and end points
on Z–axis (mm or inch) .
For facing screw, distance is specified
as U on X-axis.
Spindle speed (rev/rein)
Spindle speed for movement between
start and end points (rev)
i
-(F +$) + (F +*)2 +2. K.W
N=
K
Equaticm for limit in a. (i)
F + ~ + KN S 500.000 mm/rev or
50.0000 in/rev
Equaticm for limit in a. (ii)
(F+~-)2+2Kw>I)
Equaticm for limit in a. (iii)
~KN2 S 4194, 303 mm or
419,4303 in
Equaticln for limit in a. (iv)
&
. K.N S 5,400 mm/min or 540 in/rein
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