Ellipse - HEIDENHAIN TNC 370 User Manual

7 Programming with Q Parameters
7.8 Examples for Exercise
Ellipse
X coordinate calculation: X = a cos a
Y coordinate calculation: Y = b sin a
a, b : Semimajor and semiminor axes of the
ellipse
a
: Angle between the leading axis and
the connecting line from P to the
center of the ellipse.
Process:
The points of the ellipse are calculated and
connected by many short lines. The more
points that are calculated and the shorter
the lines between them, the smoother the
curve.
The machining direction can be varied by
changing the entries for start and end angles,
The input parameters are listed below in blocks
1 to 12.
Part program
0 BEGIN PGM 360079 MM ....................................... Load data
1 FN 0: Ql = +50 ...................................................... .X coordinate for center of ellipse
2 FN 0: 02 = +50 ....................................................... Y coordinate for center of ellipse
3 FN 0: Q3 = +50 ....................................................... Semiaxis in X
4 FN 0: 04 = +20 .......................................................
Semiaxis in Y
5 FN 0: Q5 = +0 ......................................................... Start angle
6 FN 0: Q6 = +360 ..................................................... End angle
7 FN 0: Q7 = +40 ....................................................... Number of calculating steps
8 FN 0: 08 = +0 .........................................................
Rotational position
9 FN 0: 09 = +I0 ....................................................... Depth
10 FN 0: QIO = +I00 ................................................. Plunging feed rate
11 FN 0: Ql 1 = +350 ................................................. Milling feed rate
12 FN 0: Q12 = +2 ..................................................... Setup clearance Z
13 BLK FORM 0.1 Z X+0 Y+O Z-20
14 BLK FORM 0.2 X+1 00 Y+lOO Z+O ....................... Define workpiece blank
15 TOOL DEF 1 L+O R+2.5
16 TOOL CALL 1 Z S2800
17 L Z+2000 RO F MAX M ......................................... Retract in Z
18 CALL LBL IO REP ................................................. Call subprogram ellipse
19 L Z+200 RO F MAX MO2 ....................................... Retract in Z, end of main program
Continued
7-l 8
TNC 370