1.
The incremental encoder is capable of sensing
A
direction of movement of the table
B
direction of rotation of the lead screw
C
direction of rotation of the motor
D
none of the above
Loading practice questions
21 practice sets · Page 1 of 2
The incremental encoder is capable of sensing
direction of movement of the table
direction of rotation of the lead screw
direction of rotation of the motor
none of the above
The function of the tachogenerator is
reduction of basic length unit
faster response of the motor
to make 3-D interpolation possible
none of the above
On the CNC lathe
2-D programming is sufficient
3-D programming is necessary
1-D programming is sufficient
none of the above
Interpolator is present in case of
Point-to-point open loop system
point-to-point closed loop system
contouring control system
none of the above
In order to produce a circular group in milling in CNC machining centre
a universal dividing head is necessary
a planetary gear mechanism which actuates the table moment
a rotary table is necessary
none of the above
In computer-controlled machine tools, tool movements are controlled by
Cam
machine operator
foolproof mechanism
none of the above
In computer controlled machine tools terminal clergy, machining centre is
the origin of the machine coordinate system with respect to which the operator has to make his program
the centre of the cutter which actually goes to the programmed point when used without radius compensation
a computer-controlled machine tool capable of a variety of operations involving rotating cutters
none of the above
In a point-to-point feed axis employing a stepper motor as a prime mover
an encoder for position feedback is a must
an interpolator is a must
a tachogenerator is a must
none of the above
In a CNC turning centres, threads of different pitches are cut by
Different settings of the meander drive and Norton Tumbler gears
Different settings of the feed gearbox
Different settings of the speed gearbox
none of the above
What is the purpose of using recirculating ball screw nut mechanism in CNC machine
to reduce the setup time
for higher surface finish
for carrying out up-milling
to remove backlash
In a CNC milling machine, a circular cutter is always produced, by
by operators skill and experience
by copy milling
by combine motion of feed axis
none of the above
In a CNC machining centre, any complex cutting motion involving X, Y and Z moments is carried out by
Use of jigs, cams, templates and tracers
skill of the machine operator
combinations of movements obtained from motors along the axis
none of the above
Holes are to be drilled on the circumference of a circle with regular angular spacing. If a CNC machine is used it should essentially
Have one indexing head mounted on the machine table
Have a CNC rotary axis of motion to rotate the table, about Z-axis (inaddition to X, Y and Z axes of rotation)
Be a CNC milling machine with contouring control
none of the above
For milling a bilaterally symmetrical 2-D profile on metal plate 10 millimetres thick, a CNC milling machine would require the following accessory or attachment
Copy milling attachment
Dividing head
Reversing table
none of the above
The main advantage of computer numerical control over conventional automatic control which is referred to sometimes as fixed automation is
CNC is stylish while automatic conventional control is not
CNC allows for application of higher cutting speeds and feeds
CNC is applicable in unmanned satellites
CNC offers higher flexibility than conventional automatic control (fixed automation)
CNC machining has the following main advantage over conventional machining practice
ability to employ higher cutting speeds, feeds and depth of cut
feedback control
flexibility
none of the above
CNC is not applicable in
Drilling machine
Milling machine
Lathe
none of the above
A machine will be said to have CNC control if
The dimensions of the work piece are measured by sensors while cutting is going on
The tool motion is guided by drum cams and disc cams
the loading and unloading of the work piece ON and OFF the machine respectively is made automatic
control is achieved by employment of alphanumeric data
A CNC milling machine would have
Point-to-point open loop control only
Point-to-point closed loop control only
Countering control
none of the above
A CNC machine tool has a continuous part control both linear and circular along X, Y, Z and control of table rotation about X axis and Z axis, so the machine should be called
2C, L
3L, 2C
5C
none of the above