Anna University, Chennai
ME2203: Kinematics of Machinery
Instructions: (Given by University Examination question paper)
1. Answer ALL questions.
2. Sketches should be drawn neatly.
3. Give brief procedure for graphical constructions.
4. Answers without units and with wrong units will carry less marks.
5. Symbols used in the solutions should be explained at least once for each answer.
6. Answers without substituting the data in the equations will carry zero marks
7. A3 size drawing sheet will be supplied on request. Use both sides of the drawing sheet, if necessary.
8. Fold the drawing sheet to the size of the answer sheet and attach it.
T8247, NOVEMBER 2006
2 Marks Questions
1. Differentiate between machine and mechanism.
2. Write down Kutzhback criterion to find the mobility of a planar mechanism.
3. Define transmission angle and its significance.
4. How will you determine the magnitude and direction of coriolis component of acceleration?
5. List the classifications of cam followers based on shape.
6. What are the essential design features of high speed cams?
7. Define (a) Module (b) Diametral Pitch of gears.
8. What is under cutting of gears? .
9. Distinguish between sliding and rolling friction.
10. State the condition for transmission of maximum power in belt drives.
T8248, NOVEMBER 2006
11. What is Kutzbach criterion for planar mechanism?
12. Sketch an exact straight line mechanism, with link proportions.
13. Explain normal component of acceleration.
14. State Corioli's law.
15. What are the classifications of cams based on contact surfaces?
16. State the basic requirements for high speed cams.
17. Define module of gears and its relation to circular pitch.
18. Explain briefly the use of differential in an automobile.
19. What are timing belts?
20. Explain briefly significance of friction in braking.
C3298, MAY 2007
21. Enumerate the difference between a Machine and a Structure.
22. List out the inversions of a double slider crank chain.
23. Define rubbing velocity.
24. Define Corioli's component of acceleration.
25. State the expressions for maximum velocity and acceleration of a follower moves with Cycloidal motion.
26. What is prime circle of a cam? What is the radial distance between the prime circle and base circle for a cam with knife edge follower?
27. What is axial pitch of a helical gear?
28. List out the applications of epicyclic gear train.
29. What is the condition of maximum efficiency of a Screw jack?
30. What are the advantages of wire ropes over fabric ropes?
R3456, NOVEMBER 2007
31. Define Degree of Freedom and give the DOF for a shaft in a circular hole.
32. State Grashof’s law for a four bar linkage.
33. What is Corioli's component of acceleration?
34. State the Freudenstein's equation for a four-bar mechanism.
35. What is a circular arc cam?
36. State the expressions for maximum velocity and acceleration of a follower moves with cycloidal motion.
37. Differentiate diametral pitch and circular pitch of a friction wheel.
38. What is reverted gear train?
39. Diagrammatically represent the forces acting on a body when it slides either up or down on an inclined plane with out considering the effect of friction.
40. List out any four desirable characteristics of brake lining material.
T3348, APRIL 2008
41. Define degree of freedom.
42. Define Grashoffs law.
43. Explain the coriolis component of acceleration.
44. What is higher pair?
45. Define pitch curve of the cam.
46. Define undercutting in Gears.
47. Define interference in Gears.
48. Define pressure angle and explain the effect of different pressure angle.
49. What is creep in the case of belt?
50. Which type of screw thread is preferable in power transmission?
T8247, NOVEMBER 2006 16 Marks Questions
1. (i) Describe Whitworth's quick return mechanism. (6)
(ii) Distance between two parallel shafts connected by oldham’s coupling is 25 mm.
Determine maximum speed of sliding of tongue of intermediate piece in the slot in the flange
if driving shaft is run at 250 rpm. (4) (iii) Discuss the application of Grashoff’s law in identifying the input and output motions
of four-bar mechanism. (6)
2. (i) Define and explain inversion of mechanisms. (4)
(ii) Sketch and explain oldham’s coupling. (6) (iii) Design a four-bar crank rocker quick return mechanism to give a time ratio of 1.25 with rocker swing angle as 75° clockwise. Assume the output link (rocker) length as 50 mm and in the left extreme position it is vertical. (6)
3. (i) A four bar mechanism DABC has the following dimensions :
DA = 300 mm; CB = AB = 360 mm; DC = 600 mm. Link DC is fixed and angle ADC is Driving link DA turns clockwise at 100 rpm. Constant driving torque is 50 N-m. Determine the following: (1) Velocity of point B (2) Angular velocity of driven link CB (3) Mechanical advantage of mechanism in this position (4) Resisting torque. (12)
(ii) Sketch a four-bar crank rocker mechanism in (1) Maximum transmission angle
position and (2) toggle position where mechanical advantage is infinity. (4)
4. (i) Find the number of instantaneous centres for a six link mechanism. State the use of instantaneous centre method in kinematic analysis. (4)
(ii) Crank of a slider crank mechanism rotates clockwise at a constant speed of 300 rpm, crank and connecting rod are of lengths 150 mm and 600 respectively. Determine the following; at a crank angle of 45° from inner dead centre position (1) Linear velocity and acceleration of the midpoint of connecting rod (2) Angular velocity and angular acceleration
of the connecting rod. (12)
5. (i) Explain the following terms : (1) Prime circle (2) Pressure Angle related to cams. (4) (ii) Draw the profile of a disc cam to give uniform motion and uniform velocity during
outstroke of 25 mm to a knife edge follower during first half revolution. Return of cam is also of similar uniform motion with uniform velocity during remaining half revolution. Minimum radius of the cam is 25 mm. Assume that the axis of knife edge follower passes through cam axis. (12)
6. (i) Briefly explain the features of mushroom followers. (4) (ii) Draw the profile of a cam to give following motion to a flat faced reciprocating follower. (1) Follower to have a stroke of 20 mm during 120° of cam rotation. (2) Follower to dwell for 30° of cam rotation (3) Follower to return to initial position during 120° of cam
rotation. (4) Follower to dwell for remaining 90° of cam rotation. The base circle radius is 40
mm and the follower axis coincides with cam axis of rotation. (12)
7. (i) Discuss the advantages of involute gear tooth profile. (4) (ii) Describe the advantages and applications of helical, bevel and worm gears. (6)
(iii) In an epicyclic gear train, the sum gear A and the planet gear B are having 36 and 45
teeth respectively. If the arm rotates at 150 rpm counter clockwise about center of A which is
fixed, determine speed of gear B. If the arm is locked and gear A rotates at 300 rpm what is
the speed of gear B? (6)
8. (i) A pinion having 25 teeth drives a gear of 60 teeth. Tooth profile is involute with pressure angle of 20°, module of 8 mm and addendum of 1 module. Determine: (1) Length of
path of contact (2) Lengtof arc of contact and (3)contact ratio. (6)
(ii) Design a compound gear train for an exact train ratio of 180 : 1. Minimum teeth on
any gear shall be 12 to avoid interference and Maximum gear ratio in any one stage is 10 : 1.
Also sketch the arrangement. (6) (iii) Discuss the necessity of differentials in automobiles. (4)
9. (i) Discuss the advantages of V belts. (6)
(ii) A rope drive transmits 600 kW from a pulley of effective diameter 4 m, which runs at
90 rpm. Angle of lap is 160°; angle of groove is 45°; co-efficient of friction is 0.28; mass of rope is 1.5 kg/m and allowable tension per rope is 2400 N. Determine the number of ropes required. (6)
(iii) Describe the features of internal expanding brakes used in automobiles. (4)
T8248, NOVEMBER 2006
11. (i) What is meant by interference in gears? What are the measures to eliminate the same? (
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