beautypg.com

HEIDENHAIN TNC 320 (77185x-01) ISO programming User Manual

Page 190

background image

Programming: Programming contours

6.3

Approaching and departing a contour

6

190

TNC 320 | User's Manual for DIN/ISO Programming | 3/2014

Approaching on a circular path with tangential
connection:

APPR CT

The tool moves on a straight line from the starting point P

S

to an

auxiliary point P

H

. It then moves from PH to the first contour point

PA following a circular arc that is tangential to the first contour

element.
The arc from P

H

to P

A

is determined through the radius R and

the center angle

CCA. The direction of rotation of the circular arc

is automatically derived from the tool path for the first contour

element.

Use any path function to approach the starting point P

S

.

Initiate the dialog with the

APPR/DEP key and APPR CT soft key:

Coordinates of the first contour point P

A

Radius R of the circular arc

If the tool should approach the workpiece in the

direction defined by the radius compensation:

Enter R as a positive value
If the tool should approach from the workpiece

side: Enter R as a negative value.

Center angle

CCA of the arc

CCA can be entered only as a positive value.
Maximum input value 360°

Radius compensation

G41/G42 for machining

Approaching on a circular path with tangential
connection from a straight line to the contour:
APPR LCT

The tool moves on a straight line from the starting point P

S

to

an auxiliary point P

H

. It then moves to the first contour point P

A

on a circular arc. The feed rate programmed in the APPR block is

effective for the entire path that the TNC traversed in the approach

block (path P

S

to P

A

).

If you have programmed the coordinates of all three principal axes

X, Y and Z in the approach block, the TNC moves the tool from the

position defined before the APPR block simultaneously in all three

axes to the auxiliary point PH and then, only in the working plane,

from P

H

to P

A

.

The arc is connected tangentially both to the line P

S

–P

H

as well

as to the first contour element. Once these lines are known, the

radius then suffices to completely define the tool path.

Use any path function to approach the starting point P

S

.

Initiate the dialog with the

APPR/DEP key and APPR LCT soft

key:

Coordinates of the first contour point P

A

Radius R of the circular arc. Enter R as a positive

value
Radius compensation

G41/G42 for machining