Omron trajexia CJ1W-MCH72 Operation Manual page 305

How-to's
5-1-3-8 Example 6
294
With these settings, executing MOVE(50) moves the moving part 50 mm, or
one station.
M
17-bit absolute
1:3 Gear
encoder
The mechanical system consists of a ball screw. It uses a servo motor with a
17-bit absolute encoder. The mechanical gear ratio of the gearbox is 1:3. The
screw pitch of the ball screw is 10mm per revolution. The total travel distance
of the ball screw is 540 mm. The mechanical measurement units must be mm.
With the same procedure as in example 1, we have:
17
.
Pn202 2 encoder_counts
UNITS =
.
Pn203 1 motor_revolution 1 ballscrew_revolution
17
.
2 3 encoder_counts
=
10 mm
Therefore:
One solution is:
The calculation of the multiturn limit setting parameter Pn205 is not needed in
this case because the ball screw is a system with a fixed (limited) axis. It is
enough to set this value large enough to have the overflow of the counter out
of the effective position. Also, because of the axis is finite, it is not important to
set the REP_OPTION parameter, because REP_DIST must be set large
enough so it is outside of the maximum effective position (540 mm). One
solution is: REP_DIST = 1000 and REP_OPTION = 0.
With these setting, executing MOVE(17) moves the ball screw 17 mm in
forward direction.
15
UNITS = 2 = 32768
Pn202 = 1
Pn203 = 15
Pn205 = 4
REP_DIST = 50
REP_OPTION = 1
10mm
.
3 motor_revolution
.
Pn202
3
17 17
UNITS = 2 = 2
Pn203 10
16
UNITS = 2 = 65536
Pn202 = 3
Pn203 = 5
Section 5-1
540mm
.
1 ballscrew_revolution
10mm
3 3
16
= 2
.
2 5 5
=