EME-502/Mr. Sudhir Kumar Katiyar, Ms. Preeti Murya Date: 31/10/2013

Page-1

SHRI RAMSWAROOP MEMORIAL COLLEGE OF ENGG. & MANAGEMENT

B.Tech. [SEM V (ME)] QUIZ TEST-2

(Session : 2013-14)

THEORY OF MACHINE-1 (EME-502)

Roll No.

(To be filled by the Student) Note: Attempt all the questions

Part – A (Questions from Tutorial Sheet)

[10 Marks] Q1) A Cam drives a flat reciprocating follower in the following manner: During first 120° rotation of the cam, follower moves outwards through a distance of 20 mm with simple harmonic motion. The follower dwells during next 30° of cam rotation. During next 120° of cam rotation, the follower moves inwards with simple harmonic motion. The follower dwells for the next 90° of cam rotation. The minimum radius of the cam is 25 mm. Draw the profile of the cam. (Q-6) [5] Q2) Draw the displacement, velocity and acceleration diagrams for a follower when it moves with uniform acceleration and retardation. Derive the expression for velocity and acceleration during outstroke and return stroke of the follower. (Q-2)

[3+2]

Part – B [20 Marks]

Q1) Derive the expression for displacement, max velocity and max acceleration for a tangent cam operating on a reciprocating roller follower. [2+2+2]  

Q2)(i) Show that the offset given to the follower in a cam follower mechanism reduce the wear. [4]

(ii) What are the disadvantage of knife edge and roller follower? [1+1] Q3) Draw the profile for the disc cam offset 20mm to the right of the center of the cam shaft. The base circle diameter is 75 mm and the diameter of the roller is 10mm. The follower is to move outward a distance of 40 mm with S.H.M. in 140° of the cam rotation to dwell for 40° of cam rotation to move inward with 150 °of cam rotation with uniform acceleration and retardation . Calculate maximum velocity and acceleration of follower during each stroke if the cam shaft rotates at 90 r.p.m. [4+2+2]

__________X__________

`Academic/26 Refer/WI/ACAD/18

Max. Marks: 30Time: 1 Hour

EME-502/Mr. Sudhir Kumar Katiyar, Ms. Preeti Murya Date: 31/10/2013

Page-1

SHRI RAMSWAROOP MEMORIAL COLLEGE OF ENGG. & MANAGEMENT

B.Tech. [SEM V (ME)] QUIZ TEST-2

(Session : 2013-14)

THEORY OF MACHINE-1 (EME-502)

Roll No.

(To be filled by the Student) Note: Attempt all the questions

Part – A (Questions from Tutorial Sheet)

[10 Marks] Q1) Derive the expression and plot graphs for displacement, velocity and acceleration of follower moving with uniform velocity. (Q-10) [2+3] Q2) A cam, with a minimum radius of 25 mm, rotating clockwise at a uniform speed is to be designed to give a roller follower, at the end of a valve rod, motion described below:

To raise the valve through 50 mm during 120° rotation of the cam To keep the valve fully raised through next 30° To lower the valve during next 60° To keep the valve closed during rest of the revolution i.e. 150°

The diameter of the roller is 20 mm and the diameter of the cam shaft is 25 mm. Draw the profile of the cam when the line of stroke of the valve rod passes through the axis of the cam shaft. The displacement of the valve, while being raised and lowered, is to take place with simple harmonic motion. Determine the maximum acceleration of the valve rod when the cam shaft rotates at 100 r.p.m.(Q-9)

[3+2]

Part – B

[20 Marks] Q1) Derive the expression for displacement, max velocity and max acceleration for a tangent cam operating on a reciprocating roller follower. [2+2+2]   Q2)(i) Show that the offset given to the follower in a cam follower mechanism reduce the wear. [4] (ii) What are the disadvantages of knife edge and roller follower?   [1+1]

Q3) Draw the profile for the disc cam offset 20mm to the right of the center of the cam shaft. The base circle diameter is 75 mm and the diameter of the roller is 10mm. The follower is to move outward a distance of 40 mm with S.H.M. in 140° of the cam rotation to dwell for 40° of cam rotation to move inward with 150 °of cam rotation with uniform acceleration and retardation . Calculate maximum velocity and acceleration of follower during each stroke if the cam shaft rotates at 90 r.p.m. [4+2+2]

__________X__________

`Academic/26 Refer/WI/ACAD/18

Max. Marks: 30Time: 1 Hour

EME-502/Mr. Sudhir Kumar Katiyar, Ms. Preeti Murya Date: 02/ 09/2013

Page-1

SHRI RAMSWAROOP MEMORIAL COLLEGE OF ENGG. & MANAGEMENT

B.Tech. [SEM V (ME)] QUIZ TEST-2

(Session : 2013-14)

THEORY OF MACHINE-1 (EME-502)

Roll No.

(To be filled by the Student) Note: Attempt all the questions

Part – A (Questions from Tutorial Sheet)

[10 Marks] Q1) A cam is to be designed for a knife edge follower with the following data :

Cam lift = 40 mm during 90° of cam rotation with simple harmonic motion. Dwell for the next 30°. During the next 60° of cam rotation, the follower returns to its original position with simple

harmonic motion. Dwell during the remaining 180°.

Draw the profile of the cam when the line of stroke is offset 20 mm from the axis of the cam shaft towards right. The radius of the base circle of the cam is 40 mm. Determine the maximum velocity and acceleration of the follower during its ascent and descent, if the cam rotates at 240 r.p.m. (Q-4)

[3+2] Q2) With neat sketch define following terms: a) Base Circle b) Trace Point c) Pitch Point d) Pitch Circle e) Pressure Angle (Q-7) [1+1+1+1+1]

Part – B [20 Marks]

Q1) Derive the expression for displacement, max velocity and max acceleration for a tangent cam operating on a reciprocating roller follower. [2+2+2]   Q2)(i) Show that the offset given to the follower in a cam follower mechanism reduce the wear. [4] (ii) What are the disadvantages of knife edge and roller follower? [1+1]

Q3) Draw the profile for the disc cam offset 20mm to the right of the center of the cam shaft. The base circle diameter is 75 mm and the diameter of the roller is 10mm. The follower is to move outward a distance of 40 mm with S.H.M. in 140° of the cam rotation to dwell for 40° of cam rotation to move inward with 150 °of cam rotation with uniform acceleration and retardation . Calculate maximum velocity and acceleration of follower during each stroke if the cam shaft rotates at 90 r.p.m in clockwise direction. [4+2+2]

__________X__________

`Academic/26 Refer/WI/ACAD/18

Max. Marks: 30Time: 1 Hour

EME-502/Mr. Sudhir Kumar Katiyar, Ms. Preeti Murya Date: 02/ 09/2013

Page-1

SHRI RAMSWAROOP MEMORIAL COLLEGE OF ENGG. & MANAGEMENT

B.Tech. [SEM V (ME)] QUIZ TEST-2

(Session : 2013-14)

THEORY OF MACHINE-1 (EME-502)

Roll No.

(To be filled by the Student) Note: Attempt all the questions

Part – A (Questions from Tutorial Sheet)

[10 Marks] Q1) Draw the displacement, velocity and acceleration diagrams for a follower when it moves with simple

harmonic motion. Derive the expression for velocity and acceleration during outstroke stroke of the follower. (Q-3)

[3+2]

Q2) A cam is to give the following motion to a knife-edged follower:

Outstroke during 60° of cam rotation Dwell for the next 30° of cam rotation Return stroke during next 60° of cam rotation Dwell for the remaining 210° of cam rotation.

The stroke of the follower is 40 mm and the minimum radius of the cam is 50 mm. The follower moves with uniform velocity during both the outstroke and return strokes. Draw the profile of the cam when the axis of the follower passes through the axis of the cam shaft. (Q-8)

[5] Part – B

[20 Marks] Q1) Derive the expression for displacement, max velocity and max acceleration for a tangent cam operating on a reciprocating roller follower. [2+2+2]   Q2) (i) Show that the offset given to the follower in a cam follower mechanism reduce the wear. [4]      (ii) What are the disadvantages of knife edge and roller follower? [1+1]

Q3) Draw the profile for the disc cam offset 20mm to the right of the center of the cam shaft. The base circle diameter is 75 mm and the diameter of the roller is 10mm. The follower is to move outward a distance of 40 mm with S.H.M. in 140° of the cam rotation to dwell for 40° of cam rotation to move inward with 150 °of cam rotation with uniform acceleration and retardation . Calculate maximum velocity and acceleration of follower during each stroke if the cam shaft rotates at 90 r.p.m in clockwise direction. [4+2+2]

__________X__________

`Academic/26 Refer/WI/ACAD/18

Max. Marks: 30Time: 1 Hour

EME-502/Mr. Sudhir Kumar Katiyar, Ms. Preeti Murya Date: 02/ 09/2013

Page-1

SHRI RAMSWAROOP MEMORIAL COLLEGE OF ENGG. & MANAGEMENT

B.Tech. [SEM V (ME)] QUIZ TEST-2

(Session : 2013-14)

THEORY OF MACHINE-1 (EME-502)

Roll No.

(To be filled by the Student) Note: Attempt all the questions

Part – A (Questions from Tutorial Sheet)

[10 Marks] Q1) Draw the Displacement, Velocity and Acceleration diagram for follower when it moves with Cycloidal Motion. Also derive the expression for it. (Q-5) [3+2]

Q2) A cam rotating clockwise at a uniform speed of 1000 r.p.m. is required to give a roller follower the motion defined below:

Follower to move outwards through 50 mm during 120° of cam rotation Follower to dwell for next 60° of cam rotation Follower to return to its starting position during next 90° of cam rotation Follower to dwell for the rest of the cam rotation.

The minimum radius of the cam is 50 mm and the diameter of roller is 10 mm. The line of stroke of the follower is off-set by 20 mm from the axis of the cam shaft towards right. If the displacement of the follower takes place with uniform and equal acceleration and retardation on both the outward and return strokes, draw profile of the cam. (Supplementary Q-1) [5]

Part – B

[20 Marks] Q1) Derive the expression for displacement, max velocity and max acceleration for a tangent cam operating on a reciprocating roller follower. [2+2+2]   Q2)(i) Show that the offset given to the follower in a cam follower mechanism reduce the wear. [4] (ii) What are the disadvantages of knife edge and roller follower? [1+1]      

Q3) Draw the profile for the disc cam offset 20mm to the right of the center of the cam shaft. The base circle diameter is 75 mm and the diameter of the roller is 10mm. The follower is to move outward a distance of 40 mm with S.H.M. in 140° of the cam rotation to dwell for 40° of cam rotation to move inward with 150 °of cam rotation with uniform acceleration and retardation . Calculate maximum velocity and acceleration of follower during each stroke if the cam shaft rotates at 90 r.p.m in clockwise direction. [4+2+2]

__________X__________

`Academic/26 Refer/WI/ACAD/18

Max. Marks: 30Time: 1 Hour