Question

A dc servomotor is coupled to a lead screw which drives the tables of a CNC machine tool. A digital encoder, mounted at the end of the screw, emits 500 pulses per revolution. If the pitch is 5 mm per rev, and the motor rotates 600 rpm (1 : 1 gear ratio), then table speed (m/min) and BLU (mm) are respectively.

• A. 300, 0.01
• B. 300, 0.001
• C. 3000, 0.01
• D. 3, 0.01

Answer 1

The correct option is D 3, 0.01

Table speed, V = P $\times$ rpm

= 5 $\times$ 600 = 3000 mm/min

= 3 m/min

$BLU=\frac{5}{500}=0.01mm$