Omron SYSMAC C200H-NC111, Руководство по эксплуатации

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8
frequency of the pulse train.
Positioning pulse
1 2 n
Positioning output
Angle of
rotation
Angle of rotation
Simplified Positioning
System Design
The following diagram and parameters illustrate a simplified positioning sys-
tem.
P
Stepping motor
Reduction gear
Object being
positioned
M: Reduction ratio
P: Feed screw pitch (mm/revolution)
V: Feed velocity of object being positioned (mm/s)
θ
s: Stepping angle per pulse (degree/pulse)
N
M
V
Feed screw pitch
The positioning accuracy in mm/pulse is computed as follows:
Positioning accuracy = P/(pulses per revolution x M)
= P/((360/S) x M))
= (P x S)/(360 x M)
The required pulse frequency from the Unit in pulses per second is computed
as follows:
Pulse frequency = V/Positioning accuracy
= (360 x M x V)/(P x S)
And the required number of pulses to feed an object by a distance L in mm is
computed as follows:
Number of pulses = L/Positioning accuracy
= (360 x M x L)/(P x S)
1–4–2 Semi-closed-loop System
When the Position Control Unit is used in a semiclosed-loop system, the sys-
tem supplies feedback to compensate for any discrepancy between target
values and actual values in position or speed. This system detects motor ro-
Control System Principles
Section 1–4