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
Summary of Contents for TNC 620 Programming Station
Page 4: ......
Page 5: ...Fundamentals ...
Page 28: ...Contents 28 HEIDENHAIN TNC 620 ISO Programming User s Manual 9 2016 ...
Page 57: ...1 First Steps with the TNC 620 ...
Page 77: ...2 Introduction ...
Page 110: ......
Page 111: ...3 Fundamentals file management ...
Page 166: ......
Page 167: ...4 Programming aids ...
Page 194: ......
Page 195: ...5 Tools ...
Page 234: ......
Page 235: ...6 Programming contours ...
Page 284: ......
Page 285: ...7 Data transfer from CAD files ...
Page 304: ......
Page 305: ...8 Subprograms and program section repeats ...
Page 323: ...9 Programming Q parameters ...
Page 384: ......
Page 385: ...10 Miscellaneous functions ...
Page 407: ...11 Special functions ...
Page 433: ...12 Multiple axis machining ...
Page 475: ...13 Pallet management ...
Page 480: ......
Page 481: ...14 Manual Operation and Setup ...
Page 549: ...15 Positioning with Manual Data Input ...
Page 554: ......
Page 555: ...16 Test Run and Program Run ...
Page 590: ......
Page 591: ...17 MOD Functions ...
Page 622: ......
Page 623: ...18 Tables and Overviews ...