Omron OMNUC W Series Manual page 64

Electronic Gear Settings When Using a Ball Screw
If using a ball screw, first check the following specifications.
• Number of encoder pulses
• Gear ratio
• Ball screw pitch
The following system example shows the formulas when the command unit is set to 0.001
mm.
7 revolutions
Encoder Motor
No. of encoder pulses=
2048 x 4
Moving distance of
Moving distance of load per revolution (mm)
=
load per revolution
(command unit)
G2 = [Moving distance of load per revolution (command unit)] ×
[Gear ratio (load rev.)] = 6000 × 5 = 30000
G1 = (Encoder pulses) × (Pulse multiplier) × [Gear ratio (motor rev.)] = 2048 × 4 × 7
= 57344
G1/G2 = 57344/30000 = 1.911 ⋅ ⋅ ⋅
Data ranges are shown below.
G2 ≤ 10,000,000
G1 ≤ 10,000,000
0.01 ≤ G1/G2 ≤ 100
By storing the value of G2 in Pn811 and the value of G1 in Pn810, you can use the Elec-
tronic Gear function. These parameters are enabled when the power is turned ON. After you
have changed the parameter, execute the Unit Reset Command or the Reset Service to the
Identity Object.
Note 1. The command unit explained in Electronic Gear Settings When Using a Ball Screw is based on
a unit of 0.001 mm. The speed and other parameters must be interpreted as follows:
×
Pn821: Speed [ 1,000 steps/min]
2. Setting G1/G2 outside the range 0.01 to 100 may result in a misoperation. Make sure to set G1
and G2 within this range.
DeviceNet Unit
R88D-WT
1 G1
1 G2
0.001 mm 0.001 mm
5 revolutions
Pitch of ball screw
command unit (mm)
→
[mm/min]
5-11
5.3 Parameter Details
P=6 mm
6 mm
=
=
6000
0.001 mm
5