HEIDENHAIN TNC 620 Programming Station, Руководство пользователя

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Approaching and departing a contour 6.3
6
HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016
245
Important positions for approach and departure
Starting point P
S
You program this position in the block before the APPR block.
P
S
lies outside the contour and is approached without radius
compensation (G40).
Auxiliary point P
H
Some of the paths for approach and departure go through an
auxiliary point P
H
that the TNC calculates from your input in the
APPR or DEP block. The TNC moves from the current position
to the auxiliary point P
H
at the feed rate last programmed. If you
have programmed
G00
(positioning at rapid traverse) in the last
positioning block before the approach function, the TNC also
approaches the auxiliary point P
H
at rapid traverse.
First contour point P
A
and last contour point P
E
You program the first contour point P
A
in the APPR block. The
last contour point P
E
can be programmed with any path function.
If the APPR block also includes the Z coordinate, then the TNC
moves the tool simultaneously to the first contour point P
A
.
End point P
N
The position P
N
lies outside of the contour and results from
your input in the DEP block. If the DEP block also includes the Z
coordinate, then the TNC moves the tool simultaneously to the
end point P
N
.
Abbreviation Meaning
APPR
Approach
DEP
Departure
L
Line
C
Circle
T
Tangential (smooth connection)
N
Normal (perpendicular)
When moving from the actual position to the
auxiliary point P
H
the TNC does not check whether
the programmed contour will be damaged. Use the
test graphics to check.
With the
APPR LT
,
APPR LN
and
APPR CT
functions,
the TNC moves the tool from the actual position to
the auxiliary point P
H
at the feed rate/rapid traverse
that was last programmed. With the
APPR LCT
function, the TNC moves to the auxiliary point P
H
at
the feed rate programmed with the APPR block. If no
feed rate is programmed before the approach block,
the TNC generates an error message.
R0=G40; RL=G41; RR=G42