Fagor VNP400, Manual

Page: 42 / 99

Page Chapter: 3 Section:
10
MACHINE PARAMETERS
Example 2:
To obtain a 0.1µm resolution on a linear axis with sinusoidal feedback
signal.
The multiplying factor that the DRO applies to sinusoidal feedback signals can
be x5, x10, x20 or x25 besides x2 and x4. Therefore the obtainable values are:
x2 x4
x5 x10 x20
x10 x20 x40
x20 x40 x80
x25 x50 x100
Using a linear scale with a grading pitch of 20 µm, the maximum possible
resolution is 20µm/100 = 0.2µm and 0.1µm with a grading pitch of 10µm
(10µm/100).
Therefore, a sinusoidal linear scale with a 10µm pitch will be used.
Grading pitch 10µm
Px05 = SINEWAVE
Px06 = LINEAR
Px07 = MM/DEG
Px10 = x4
Px11 = x25
Px12 = 0.0001
Example 3:
To obtain a 0.0002" resolution with 5 turns/inch (0.2 inch/turn) leadscrew and
squarewave encoder.
The multiplication factor that the DRO applies to square feedback signals can
be x2 or x4. Therefore the encoder must provide the following pulses per
revolution.
leadscrew pitch
number of pulses =
Factor x Resolution
a) Px05 = SQUARE b) PX05 = SQUARE
Px06 = LINEAR Px06 = LINEAR
Px07 = INCHES/DMS Px07 = INCHES/DMS
Px10 = x2 Px10 = x4
Px11 = — Px11 = —
Px12 = 0.0002 Px12 = 0.0002
0.2 inch/turn
a) number of pulses = = 500 Pulses/turn
2 x 0.0002 inch/pulse
0.2 inch/turn
b) number of pulses = = 250 pulses/turn
4 x 0.0002 inch/pulse
PARAMETERS FOR THE
AXES