A DC servomotor coupled to a leadscrew with a 4:1 gear reduction is used to driv
ID: 1716338 • Letter: A
Question
A DC servomotor coupled to a leadscrew with a 4:1 gear reduction is used to drive one of the table axes of a CNC milling machine. The leadscrew has 1.5 threads/cm. An optical encoder attached to the leadscrew emits 100 pulse/rev. The motor rotates at a maximum speed of 800 rev/min. Determine (a) the control resolution of the system, expressed in linear travel distance of the table axis (b) the frequency of the pulse train emitted by the optical encoder when the servomotor operates at maximum speed.
Explanation / Answer
a)
P = 1/1.5 = 2/3 cm
b)
fp = N*ns/60 = 800*100/60 = 1333.3 Hz