Lenze ETC Motion Control - Manual (Page 101)

CNC programming
G functions
G functions individual descriptions
3
3.2
3.2.2
l
101 EDSTCXN EN 2.0
The principal and secondary axes which are assigned to the current NC
channel can be selected with G16.
The path speed can be programmed under the address F. If the speed is not
programmed, the speed that was last programmed is valid.
The path speed is limited in dependence on the radius and the allowed path
acceleration according to the following formula:
F
max
= 3, 6 * R * B
Ǹ
* 1000 [mm/min] with R=radius [mm] and B=acceleration
[m/s
@]
The values programmed for E and L have a modal effect. However, the
resulting feed speed is only considered if a value not equal to zero was
programmed for L. The value programmed for E is also stored time
synchronously in P561 and can be used e.g. as the spindle speed.
Special features in the circle calculation:
When a variable radius (D) is used, the control interprets the programmed
speed as a specification for the larger radius. The angular velocity is constant
over the complete G2/G3 profile, while the programmed path speed is only
adjusted to the arc when the larger radius is reached. If a tangential
correction is programmed, the path speed is adjusted to the accelerating
performance of the corrected axis. The speed and acceleration values of the
optional linear axis are not considered.
Any inaccuracies which may occur during the calculation of the circle
geometries, which are in the window defined through the machine
constants, are compensated by the control via the delta radius. In other
words, all coordinate specifications for G2/G3 (target and center) are
interpreted as a specification which does not need to be corrected.
All the following examples for G2/G3 programming require that the XY
plane (G17) has been switched on previously.
N10 G0 X50 Y100 Approach arc starting point
N20 G2 Y200 I0 J50 F200 Travels a semi−circle clockwise from X50 Y100 to X50 Y200 with
a circle center of X50 Y150, a radius of 50 mm and a path speed
of 200 mm/min.
N30 G3 X−50 Y100 R100 Travels a quarter circle in counterclockwise direction from X50
Y200 to X−50 Y100 with a radius of 100 mm.
G0 X0 Y0 Starting position X0 Y0
G3 X40 Y40 R100 D−60 K2 Travels a spiral in counterclockwise direction with a start radius
of 100 mm, an end radius of 40 mm (R+D) and a covered angle
of 810
°
.
G0 X0 Y0 Z0 Starting position X0 Y0 Z0
G3 X10 Y0 Z115 K12 R10 Travels a helix on a cylinder surface in counterclockwise
direction with a radius of 10 mm, a length of 115 mm (Y) and a
covered angle of 4500
°
.
G0 X0 Y−30 Z−115 Starting position X0 Y−300 Z−115
G3 X30 Y0 Z0 K10 R10 D20 Travels a helix on a cone surface in counterclockwise direction
with a start radius of 10 mm, an end radius of 30 mm (R+D), a
length of 115 mm (Y) and a covered angle of 3690
°
.
Example