Materials Science and Manufacturing Engineering Miscellaneous
- The tool of an NC machine has to move along a circular arc from (5,5) to (10,10) while performing an operation. The centre of the arc is at (10,5). Which one of the following NC tool path commands performs the above mentioned operation?
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NA
Correct Option: D
NA
- NC contouring is an example of
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NA
Correct Option: A
NA
Direction: In the feed drive of a Point-to-Point open loop CNC drive, a stepper motor rotating at 200 steps/rev drives a table through a gear box and lead screw-nut mechanism (pitch = 4 mm, number of starts = 1). The gear ratio
 | = |  | is given by | |
| Input rotationalspeed |
U = 1/4. The 1 stepper motor (driven by voltage pulses from a pulse. The frequency of the pulse train from the pulse generator is f = 10,000 pulses per minute.
- Which type of motor is NOT used in axis or spindle drives of CNC machine tools?
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Step angle (α) = 360 = 1.8 200 α = 360 = 1.8 200 x = PA , A αnp 360
np is number of pulse.
np = 1 for BLUx = 4 &tims; 1.8 × Gear Ratio 360 x = 4 &tims; 1.8 × 1 360 4
x = 5 micronsCorrect Option: B
Step angle (α) = 360 = 1.8 200 α = 360 = 1.8 200 x = PA , A αnp 360
np is number of pulse.
np = 1 for BLUx = 4 &tims; 1.8 × Gear Ratio 360 x = 4 &tims; 1.8 × 1 360 4
x = 5 microns
- The Basic Length Unit (BLU), i.e., the table movement corresponding to 1 pulse of the pulse generator, is
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NA
Correct Option: B
NA
- A customer insists on a modification to change the BLU of the CNC drive to 10 microns without changing the table speed. The modification can be accomplished by
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NA
Correct Option: A
NA
