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C o nt i n uo u s C o mp r e he n s i ve E v a l ua t i on Te s t- ICourse Code: 11ME301 Course Title: Kinematics Of MachineryName of Programme: Bachelor of Engineering

Sem: V Date: 00.0 .!013 Duration: 3 hours Ma"imum Mar#s: $%

Part- A Answer All Questions(15X1=15 Marks)

1. Pantographs are used for --------------drawings and maps.

2. &he e"am'le of lo(er 'air is )))))))))))))))))))

3. &he e"am'le of s'herical 'air is ))))))))))))))))))))

4. &he e"am'le of rolling 'air is )))))))))))))))))))))))))))

5. *ectilinear motion of ' iston is con+erted into)))))))))))))))))))

6. , circular -ar mo+ing in a round hole is an e"am'le of ))))))))))))))

7. f some lin#s are connected such that motion -et(een them canta#e 'lace in more than one direction/ it is called )))))))))))))))))))

8. Link which is connected to other links at four points9. Ratchets are used to transform motion of rotation or translation into

---------------------or translation10. Toggle mechanisms are used, where large resistances are to be

overcome through---------------------11. Hooke s !oins is used to connect two ----------but intersecting shafts.12. The steering mechanism is used in automobiles for changing the

directions of the-----------with reference to the chassis, so as to movethe automobile in the desired path.

13. "etermine the no of degrees of freedom .

14. Determine the no.of e!rees of free om.

1". Determine the no.of e!rees of free om.

Part- B

Short answer Questions(5X2=10 Marks)

16. Define degrees of freedom.

1 . Classify the onstrained motion.

1!. !hat is "antogra"h#

1". !hat is meant $y transmission angle#

#oll $o:

http://www.atoziq.com/2013/07/the-example-of-lower-pair-is.htmlhttp://www.atoziq.com/2013/07/the-example-of-spherical-pair-is.htmlhttp://www.atoziq.com/2013/07/the-example-of-rolling-pair-is.htmlhttp://www.atoziq.com/2013/07/a-circular-bar-moving-in-round-hole-is.htmlhttp://www.atoziq.com/2013/07/if-some-links-are-connected-such-that.htmlhttp://www.atoziq.com/2013/07/if-some-links-are-connected-such-that.htmlhttp://www.atoziq.com/2013/07/the-example-of-lower-pair-is.htmlhttp://www.atoziq.com/2013/07/the-example-of-spherical-pair-is.htmlhttp://www.atoziq.com/2013/07/the-example-of-rolling-pair-is.htmlhttp://www.atoziq.com/2013/07/a-circular-bar-moving-in-round-hole-is.htmlhttp://www.atoziq.com/2013/07/if-some-links-are-connected-such-that.htmlhttp://www.atoziq.com/2013/07/if-some-links-are-connected-such-that.html

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20. !rite the different ty"es of gra"hi al method.

Part- #

$es%ri&ti'e Questions(5X10=50 Marks)

21. Des ri$e different in%ersions of do&$le slider ran' hain

22. a) Define the follo(ing i) *in' of a ma hine ii) +inemati ,air iii) Com"letely onstrained motion i%) +inemati hain %) Pantograph.

*) #$plain different t%pes of Link.2+. a) !hat is a 'inemati "air# - "lain different ty"es of

'inemati "airs.

*) &ith the help of a neat sketch e$plain the working of &hitworth'uick return mechanism

2,. a) Des ri$e different in%ersions of /&adri y le hain.

*) #$plain (traight line mechanism with neat sketch.

25. a) &ith the help of a neat sketch e$plain the working of )rank and(lotted lever mechanism

*) &ith the help of a neat sketch e$plainAckermann steering gearmechanism.

#oll $o:

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C C E 1 % n s & e r K e y s

Course Code: 11ME%0% Course Title: Computer Inte!rate Manufacturin!Name of Programme: Bachelor of Engineering

Sem: V Date: 00.0 .!013 Duration: 3 hours Ma"imum Mar#s: $%

Part- A Answer All Questions(15X1=15 Marks)

1. e u%in or /nlar in

2. Sli in

+. So%ket an *all arran e ent

,. Belt an &ulle

5. otation otion o the l wheel

6. 3n%o &letel %onstraine otion

. 3n%o &letel %onstraine otion

!. Quaternar link

". 3nter ittent

10. Short istan%e

11. 4on &arallel

12. heel a les

1+. 1

1,. 0

15. 1

Part- B Short answer Questions(5X2=10 Marks)

16. Define degrees of freedom.

t is defined as the n&m$er of in"&t "arameters (hi h m&st$e ontrolled inde"endently in order to $ring the de%i e into a"arti &lar "osition.

he degrees of freedom of a me hanism n) is gi%en $y

n 3 * 1) 2 h

* &m$er of lin's

&m$er of oints

h &m$er of higher "airs.

1 . Classify the onstrained motion.

here are three ty"es.

1) Com"letely onstrained motion eg. /&are $ar mo%ingin a s/&are hole)

2) n om"letely onstrained motion eg. Cir &lar shaft ina hole)

3) & essf&lly onstrained motion eg. ,iston andylinder)

1!. !hat is "antogra"h#

,antogra"h is a de%i e (hi h is &sed to re"rod& e adis"la ement e a tly in an enlarged or red& ed s ale. t is &sed indra(ing offi es for d&"li ating the dra(ings ma"s "lans et . t(or's on the "rin i"le of 4 $ar hain me hanism.

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1". !hat is meant $y transmission angle#

n a fo&r $ar hain me hanism the angle $et(een theo&"ler and the follo(er lin' is alled as the transmission angle.

.

20. !rite the different ty"es of gra"hi al method.

1) elati%e %elo ity method.

2) nstantaneo&s Centre method

Part- #

$es%ri&ti'e Questions(5X10=50 Marks)

21. Des ri$e different in%ersions of do&$le slider ran' hain

Double slider crank chain: *t is a kinematic chain consisting of twoturning pairs and two sliding pairs.Scotch Yoke mechanism.Turning pairs + , /0 (liding pairs + / 1, 1 .

2ig. ./1

Inversions of double slider crank mechanism:Elliptical trammel. This is a device which is used for generating anelliptical profile.

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2ig. ./3*n fig. ./3, if 4) 5 p and 6) 5 ', then, $ 5 '.cos7 and % 5 p.sin7.Rearranging, cossin

This is the e'uation of an ellipse. The path traced b% point ) is an ellipse, with ma!or a$is and minor a$is e'ual top and '

respectivel%.Oldham coupling. This is an inversion of double slider crank mechanism,which is usedto connect two parallel shafts, whose a$es are offset b% a small amount.

2ig. ./8

22. a) $e ine the ollowin i) 7ink o a a%hine ink or element: *t is the name given to an% bod% which hasmotion relative to another.4ll materials have some elasticit%. 4 rigid link ione, whose deformations are so small that the% can be neglected idetermining the motion parameters of the link. ii) 8ine ati% Pair he geometrical forms b% which two members of a mechanism are !oined together, so that the relative motion between these two is consistenare known as pairing elements and the pair so formed is called kinemati pair. #ach individual link of a mechanism forms a pairing element

iii) #o &letel %onstraine otion *f the constrained motion is achieved b% the pairing elementthemselves, then it is called completel% constrained motion

i') 8ine ati% %hain 4 kinematic chain is a group of links either !oined together orarranged in a manner that permits them to move relative to one another. the links are connected in such a wa% that no motion is possible, it resultsa locked chain or structure

') !antograph .

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Pantographs are used for reducing or enlarging drawings and maps.The% are also used for guiding cutting tools or torches to fabricatecomplicated shapes.

22. *) E"plain different t#pes of ink .

ink or element: *t is the name given to an% bod% which has motionrelative to another. 4ll materials have some elasticit%. 4 rigid link is one,whose deformations are so small that the% can be neglected in determiningthe motion parameters of the link.

2ig. ./$inar# link: Link which is connected to other links at two points.92ig. ./a:%ernar# link: Link which is connected to other links at three points.92ig. ./ b:&uaternar# link: Link which is connected to other links at four points92ig ./ c:

2+. a) hat is a kine ati% &air9 / &lain i erent t &es

o kine ati% &airs.

%#pes of kinematic pairs:'i( $ased on nature of contact bet)een elements:'a( o)er pair. *f the !oint b% which two members are connected hassurface contact,the pair is known as lower pair. #g. pin !oints, shaft rotatingin bush, slider in slider crank mechanism.

2ig. .8 Lower pairs'b( *igher pair. *f the contact between the pairing elements takes place at a point or along a line, such as in a ball bearing or between two gear teeth incontact, it is known as a higher pair.

2ig. .; Higher pairs'ii( $ased on relative motion bet)een pairing elements:'a( Siding pair. (liding pair is constituted b% two elements so connectedthat one is constrained to have a sliding motion relative to the other."

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'b( %urning pair 'revolute pair(. &hen connections of the two elementsare such that onl% a constrained motion of rotation of one element withrespect to the other is possible, the pair constitutes a turning pair. "

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'e( Spherical pair. 4 spherical pair will have surface contact and threedegrees of freedom. #g. 6all and socket !oint. "

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2+. *) ith the help of a neat sketch e"plain the )orking of

hit)orth /uick return mechanism

This is first inversion of slider mechanism, where, crank is fi$ed. *nput isgiven to link , which moves at constant speed. Point ) of the mechanism isconnected to the tool post " of the machine. "uring cutting stroke, tool postmoves from "to " . The corresponding positions of ) are )and ) asshown in the fig. ./=. 2or the point ) to move from )to ) , point 6moves from 6to 6 , in anti-clockwise direction. *.#.,cutting stroke takes place when input link moves through angle 6< 6 in anticlockwisedirection and return stroke takes place when input link moves through angle6 < 6 in anti-clockwise direction.

2,. a) $es%ri*e i erent in'ersions o :ua ri% % %le

%hain

0our bar chain:

2ig . 2our bar chain

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2ig. . / *nversions of four bar chain.+rank1rocker mechanism: *n this mechanism, either link or link / isfi$ed. Link 9crank: rotates completel% and link 1 9rocker: oscillates. *t issimilar to 9a: or 9b: of fig. . /.

2ig. . 1

Drag link mechanism . Here link is fi$ed and both links and 1 makecomplete rotation but with different velocities. This is similar to . /9c:.

2ig. . 3

Double crank mechanism. This is one t%pe of drag link mechanism,where, links / are e'ual and parallel and links 1 are e'ual and parallel.

2ig. . 8Double rocker mechanism. *n this mechanism, link 1 is fi$ed. Link makes complete rotation, whereas links / 1 oscillate 92ig. . /d:.

2,. *) E"plain Straight line mechanism )ith neat sketch .

Straight line motion mechanisms(traight line motion mechanisms are mechanisms, having a point thatmoves along a straight line, or nearl% along a straight line, without beingguided b% a plane surface.+ondition for e"act straight line motion:*f point 6 9fig. .1?: moves on the circumference of a circle with center < and radius

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2ig. .1?Locus of pt.) will be a straight line, A to 4# if, is constant!eaucellier e"act straight line motion mechanism:

2ig. .1

Here, 4# is the input link and point # moves along a circular path of radius4# 5 46.4lso, #) 5 #" 5 P) 5 P" and 6) 5 6". Point P of themechanism moves along e$act straight line, perpendicular to 64 e$tended.

AB AC AE const ifAB AC const butAD const To prove B, E and P lie on same straight line:Triangles 6)", #)" and P)" are all isosceles triangles having common base )" and ape$ points being 6, # and P. Therefore points 6, # and Palwa%s lie on the perpendicular bisector of )". Hence these three pointsalwa%s lie on the same straight line.To prove product of BE and BP is constant.*n triangles 62) and P2), BC = FB + FC and PC = PF + FC

BC PC = FB PF = ( FB + PF )( FB PF ) = BP BE 6ut since 6) and P) are constants, product of 6P and 6# is constant,which is the condition for e$act straight line motion. Thus point P alwa%smoves along a straight line perpendicular to 64 as shown in the fig. .1 .Appro"imate straight line motion mechanism: 4 few four barmechanisms withcertain modifications provide appro$imate straight line motions.,obert2s mechanism

2ig. .1

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This is a four bar mechanism, where, P)" is a single integral link. 4lso,dimensions 4),6", )P and P" are all e'ual. Point P of the mechanismmoves ver% nearl% along line 46.25. a) ith the help of a neat sketch e"plain the )orking of +rank

and Slotted lever mechanism

This is second inversion of slider mechanism, where, connecting rod isfi$ed. *nput is given to link , which moves at constant speed. Point ) ofthe mechanism is connected to the tool post " of the machine. "uringcutting stroke, tool post moves from "to " .The corresponding positionsof ) are ) and ) as shown in the fig. ./>. 2or the point ) to move from) to ) , point 6 moves from 6to 6 , in anti-clockwise direction. *.#.,cutting stroke takes place when input link moves through angle 6< 6 inanticlockwise direction and return stroke takes place when input link movesthrough angle 6< 6 in anti-clockwise direction

25.*) ith the help of a neat sketch e"plain the Ackermannsteering gear mechanism.

4ckerman steering mechanism, R(46 is a four bar chain as shown in

fig. .3?. Links R4 and (6 which are e'ual in length are integral with thestub a$les. These links are connected with each other through track rod 46&hen the vehicle is in straight ahead position, links R4 and (6 make e'ualangles B with the center line of the vehicle. The dotted lines in fig. .3?indicate the position of the mechanism when the vehicle is turningleft.