YASKAWA yasnac i80m

2.13
PROGRAM
SUPPORT FUNCTIONS
(Cont’d)
(b)
Two-step
feed*
In
drilling
operation,
if
the
cutting
speed
in
the
vicinity
of
drill
start
is
slowed
down,
the
accuracy
of
hole
position
can
be
increased
without
performing
center
hole
machining.
QL
INITIAL
POINT
T
R-
POINT
hiiO
:
F
FEED
Z-
POINT
Address
E:
Speed
in
1st
step
Address
tj:
Distance
for
1st
step
speedtemmanded
without
a
situii
Fig.2.13.4
(c)
Reciprocal
feed*
Cutting
speeds
in
forward
and
return
can
be
separately
commanded
such
as
in
tapping
or
boring
operations.
In
tapping
operations,
machining
can
be
completed
before
the
tap
is
fully
extended.
Furthermore,
the
machining
time
in
boring
operations
can
be
reduced.
In
reaming
operations,
possible
damage
to
the
machined
surface
in
the
return
process
can
be
prevented.
Q
INITIAL
POINT
R-POINT
F
KF.FD
E
FEED
Z-POINT
Address
E:
Return
speed
Fig.2.13.5
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172
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