KoM ppt unit1 pvpsit 2015 Basic Mechanisms
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Transcript of KoM ppt unit1 pvpsit 2015 Basic Mechanisms
February 5, 2015 1Kinematics of Machinery - Unit - I
KINEMATICS OF KINEMATICS OF MECHINERYMECHINERY
February 5, 2015 2Kinematics of Machinery - Unit - I
Example for MechanismExample for Mechanism
February 5, 2015 3Kinematics of Machinery - Unit - I
Example for MechanismExample for Mechanism
February 5, 2015 4Kinematics of Machinery - Unit - I
MACHINEMACHINE
A machine is a mechanism or collection of A machine is a mechanism or collection of mechanisms, which transmit force from the mechanisms, which transmit force from the source of power to the resistance to be source of power to the resistance to be overcome. overcome.
February 5, 2015 5Kinematics of Machinery - Unit - I
Though all machines are mechanisms, all Though all machines are mechanisms, all mechanisms are not machinesmechanisms are not machines
February 5, 2015 6Kinematics of Machinery - Unit - I
DYNAMIC/INERTIA LOADDYNAMIC/INERTIA LOAD
Inertia load require accelerationInertia load require acceleration
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February 5, 2015 8Kinematics of Machinery - Unit - I
February 5, 2015 9Kinematics of Machinery - Unit - I
February 5, 2015 10Kinematics of Machinery - Unit - I
LINK OR ELEMENTLINK OR ELEMENT
Any body (normally rigid) which has motion Any body (normally rigid) which has motion relative to anotherrelative to another
Binary linkBinary link Ternary linkTernary link Quaternary linkQuaternary link
February 5, 2015 11Kinematics of Machinery - Unit - I
KINEMATIC PAIRSKINEMATIC PAIRS
A mechanism has been defined as a combination so A mechanism has been defined as a combination so connected that each moves with respect to each other. connected that each moves with respect to each other. A clue to the behavior lies in in the nature of A clue to the behavior lies in in the nature of connections, known as kinetic pairs.connections, known as kinetic pairs.The degree of freedom of a kinetic pair is given by The degree of freedom of a kinetic pair is given by the number independent coordinates required to the number independent coordinates required to completely specify the relative movement.completely specify the relative movement.
February 5, 2015 12Kinematics of Machinery - Unit - I
TYPES OF KINEMATIC PAIRSTYPES OF KINEMATIC PAIRS
Based on nature of contact Based on nature of contact between elementsbetween elements
(i) (i) Lower pairLower pair : The joint : The joint by which two members are by which two members are connected has surface connected has surface contact. A pair is said to be a contact. A pair is said to be a lower pair when the lower pair when the connection between two connection between two elements are through the elements are through the area of contact. Its 6 types area of contact. Its 6 types are are
Revolute(Or)TurningPairRevolute(Or)TurningPair
Prismatic(Or)SlidingPairPrismatic(Or)SlidingPair
Screw(Or)HelicalPairScrew(Or)HelicalPair
CylindricalPairCylindricalPair
Spherical(Or)GlobularPairSpherical(Or)GlobularPair
Flat(or)PlanarPairFlat(or)PlanarPair
February 5, 2015 13Kinematics of Machinery - Unit - I
(ii) Higher pair:(ii) Higher pair: The contact between the The contact between the
pairing elements takes place at a point or along pairing elements takes place at a point or along a line. a line.
February 5, 2015 14Kinematics of Machinery - Unit - I
Based on relative motion between pairing elementsBased on relative motion between pairing elements
(a) Siding pair [DOF = 1](a) Siding pair [DOF = 1]
(b) Turning pair (revolute pair)(b) Turning pair (revolute pair)
[DOF = 1][DOF = 1]
February 5, 2015 15Kinematics of Machinery - Unit - I
Based on relative motion between pairing Based on relative motion between pairing
elementselements
(c) Cylindrical pair(c) Cylindrical pair [DOF = 2][DOF = 2]
(d) Rolling pair(d) Rolling pair
[DOF = 1][DOF = 1]
February 5, 2015 16Kinematics of Machinery - Unit - I
Based on relative motion between pairing Based on relative motion between pairing elementselements
(e) Spherical pair [DOF = 3](e) Spherical pair [DOF = 3]
(f) Helical pair or screw pair [DOF = 1](f) Helical pair or screw pair [DOF = 1]
February 5, 2015 17Kinematics of Machinery - Unit - I
Based on the nature of mechanical constraintBased on the nature of mechanical constraint
(a) Closed pair(a) Closed pair
(b) Unclosed or force closed pair(b) Unclosed or force closed pair
February 5, 2015 18Kinematics of Machinery - Unit - I
CONSTRAINED MOTIONCONSTRAINED MOTION
one element has got only one definite motion one element has got only one definite motion relative to the other relative to the other
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(a) Completely constrained motion(a) Completely constrained motion
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(b) Successfully constrained motion(b) Successfully constrained motion
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(c) Incompletely constrained motion(c) Incompletely constrained motion
February 5, 2015 22Kinematics of Machinery - Unit - I
KINEMATIC CHAINKINEMATIC CHAIN
Group of links either joined together or Group of links either joined together or arranged in a manner that permits them to arranged in a manner that permits them to move relative to one another. move relative to one another.
February 5, 2015 23Kinematics of Machinery - Unit - I
Kinematic ChainKinematic Chain
Relation between Links, Pairs and JointsRelation between Links, Pairs and JointsL=2P-4L=2P-4J=(3/2) L – 2J=(3/2) L – 2L => No of LinksL => No of LinksP => No of PairsP => No of PairsJ => No of JointsJ => No of JointsL.H.S > R.H.S => Locked chainL.H.S > R.H.S => Locked chainL.H.S = R.H.S => Constrained Kinematic ChainL.H.S = R.H.S => Constrained Kinematic ChainL.H.S < R.H.S => Unconstrained Kinematic L.H.S < R.H.S => Unconstrained Kinematic
ChainChain
February 5, 2015 24Kinematics of Machinery - Unit - I
LOCKED CHAIN (Or) STRUCTURELOCKED CHAIN (Or) STRUCTURE
Links connected in such a way that no relative Links connected in such a way that no relative motion is possible. motion is possible.
L=3, J=3, P=3L=3, J=3, P=3 L.H.S>R.H.SL.H.S>R.H.S
February 5, 2015 25Kinematics of Machinery - Unit - I
Kinematic Chain MechanismKinematic Chain Mechanism
Slider crank and four bar mechanismsSlider crank and four bar mechanisms
L=4, J=4, P=4L=4, J=4, P=4
L.H.S=R.H.SL.H.S=R.H.S
February 5, 2015 26Kinematics of Machinery - Unit - I
Working of slider crank mechanismWorking of slider crank mechanism
February 5, 2015 27Kinematics of Machinery - Unit - I
Unconstrained kinematic chainUnconstrained kinematic chain
L=5,P=5,J=5 L=5,P=5,J=5
L.H.S < R.H.S L.H.S < R.H.S
February 5, 2015 28Kinematics of Machinery - Unit - I
DEGREES OF FREEDOM (DOF):DEGREES OF FREEDOM (DOF): It is the number of independent coordinates required to It is the number of independent coordinates required to
describe the position of a body.describe the position of a body.
February 5, 2015 29Kinematics of Machinery - Unit - I
Degrees of freedom/mobility of a Degrees of freedom/mobility of a mechanismmechanism
It is the number of inputs (number of It is the number of inputs (number of independent coordinates) required to describe independent coordinates) required to describe the configuration or position of all the links of the configuration or position of all the links of the mechanism, with respect to the fixed link the mechanism, with respect to the fixed link at any given instant. at any given instant.
February 5, 2015 30Kinematics of Machinery - Unit - I
GRUBLER’S CRITERIONGRUBLER’S CRITERION Number of degrees of freedom of a mechanism is given by Number of degrees of freedom of a mechanism is given by
F = 3(n-1)-2l-h. Where,F = 3(n-1)-2l-h. Where, F = Degrees of freedomF = Degrees of freedom n = Number of links in the mechanism.n = Number of links in the mechanism. l = Number of lower pairs, which is obtained by counting the l = Number of lower pairs, which is obtained by counting the
number of joints. If more than two links are joined together at any number of joints. If more than two links are joined together at any point, then, one additional lower pair is to be considered for every point, then, one additional lower pair is to be considered for every additional link.additional link.
h = Number of higher pairsh = Number of higher pairs
February 5, 2015 31Kinematics of Machinery - Unit - I
Examples - DOFExamples - DOF
F = 3(n-1)-2l-hF = 3(n-1)-2l-h Here, n = 4, l = 4 & h = 0.Here, n = 4, l = 4 & h = 0. F = 3(4-1)-2(4) = 1F = 3(4-1)-2(4) = 1 I.e., one input to any one link I.e., one input to any one link
will result in definite motion will result in definite motion of all the links.of all the links.
February 5, 2015 32Kinematics of Machinery - Unit - I
Examples - DOFExamples - DOF F = 3(n-1)-2l-hF = 3(n-1)-2l-h Here, n = 5, l = 5 and h = 0.Here, n = 5, l = 5 and h = 0. F = 3(5-1)-2(5) = 2F = 3(5-1)-2(5) = 2 I.e., two inputs to any two links are I.e., two inputs to any two links are
required to yield definite motions in required to yield definite motions in all the links.all the links.
February 5, 2015 33Kinematics of Machinery - Unit - I
Examples - DOFExamples - DOF
F = 3(n-1)-2l-hF = 3(n-1)-2l-h Here, n = 6, l = 7 and h = 0.Here, n = 6, l = 7 and h = 0. F = 3(6-1)-2(7) = 1F = 3(6-1)-2(7) = 1 I.e., one input to any one link will result in I.e., one input to any one link will result in
definite motion of all the links. definite motion of all the links.
February 5, 2015 34Kinematics of Machinery - Unit - I
Examples - DOFExamples - DOF
F = 3(n-1)-2l-hF = 3(n-1)-2l-h Here, n = 6, l = 7 (at the intersection of Here, n = 6, l = 7 (at the intersection of
2, 3 and 4, two lower pairs are to be 2, 3 and 4, two lower pairs are to be considered) and h = 0.considered) and h = 0.
F = 3(6-1)-2(7) = 1F = 3(6-1)-2(7) = 1
February 5, 2015 35Kinematics of Machinery - Unit - I
Examples - DOFExamples - DOF
F = 3(n-1)-2l-hF = 3(n-1)-2l-h Here, n = 11, l = 15 (two lower Here, n = 11, l = 15 (two lower
pairs at the intersection of pairs at the intersection of 3, 4, 3, 4, 66; ; 2, 4, 52, 4, 5; ; 5, 7, 85, 7, 8; ; 8, 10, 118, 10, 11) and ) and h = 0.h = 0.
F = 3(11-1)-2(15) = 0 F = 3(11-1)-2(15) = 0
February 5, 2015 36Kinematics of Machinery - Unit - I
Examples - DOFExamples - DOF
(a)(a)F = 3(n-1)-2l-hF = 3(n-1)-2l-hHere, n = 4, l = 5 and h = 0.Here, n = 4, l = 5 and h = 0.F = 3(4-1)-2(5) = -1F = 3(4-1)-2(5) = -1I.e., it is a structureI.e., it is a structure
(b)(b)F = 3(n-1)-2l-hF = 3(n-1)-2l-hHere, n = 3, l = 2 and h = 1.Here, n = 3, l = 2 and h = 1.F = 3(3-1)-2(2)-1 = 1F = 3(3-1)-2(2)-1 = 1
(c)(c)F = 3(n-1)-2l-hF = 3(n-1)-2l-hHere, n = 3, l = 2 and h = 1.Here, n = 3, l = 2 and h = 1.F = 3(3-1)-2(2)-1 = 1F = 3(3-1)-2(2)-1 = 1
February 5, 2015 37Kinematics of Machinery - Unit - I
Grashoff LawGrashoff Law
The sum of the shortest The sum of the shortest and longest link length and longest link length should not exceed the should not exceed the sum of the other two sum of the other two link lengths.link lengths.
s+l < p+qs+l < p+q
(e.x) (1+2) < (3+4)(e.x) (1+2) < (3+4)
February 5, 2015 38Kinematics of Machinery - Unit - I
INVERSIONS OF MECHANISMINVERSIONS OF MECHANISM
A mechanism is one in which one of the links of a kinematic A mechanism is one in which one of the links of a kinematic chain is fixed. Different mechanisms can be obtained by fixing chain is fixed. Different mechanisms can be obtained by fixing different links of the same kinematic chain. These are called as different links of the same kinematic chain. These are called as inversions of the mechanism. inversions of the mechanism.
February 5, 2015 39Kinematics of Machinery - Unit - I
INVERSIONS OF MECHANISMINVERSIONS OF MECHANISM
1.Four Bar Chain1.Four Bar Chain
2.Single Slider Crank2.Single Slider Crank
3.Double Slider Crank3.Double Slider Crank
1.Four Bar Chain - Inversions1.Four Bar Chain - Inversions
February 5, 2015 40Kinematics of Machinery - Unit - I
Beam Engine (crank &Lever)Beam Engine (crank &Lever)
February 5, 2015 41Kinematics of Machinery - Unit - I
February 5, 2015 42Kinematics of Machinery - Unit - I
Double Crank MsmDouble Crank Msm
February 5, 2015 43Kinematics of Machinery - Unit - I
Double Lever Double Lever
February 5, 2015 44Kinematics of Machinery - Unit - I
2.Single Slider Crank _ 2.Single Slider Crank _ InversionsInversions
February 5, 2015 45Kinematics of Machinery - Unit - I
Single Slider Crank _ InversionsSingle Slider Crank _ Inversions
1.1.PENDULUM PUMPPENDULUM PUMP
February 5, 2015 46Kinematics of Machinery - Unit - I
February 5, 2015 47Kinematics of Machinery - Unit - I
February 5, 2015 48Kinematics of Machinery - Unit - I
2.OSCILLATING CYLINDER2.OSCILLATING CYLINDER
February 5, 2015 49Kinematics of Machinery - Unit - I
February 5, 2015 50Kinematics of Machinery - Unit - I
February 5, 2015 51Kinematics of Machinery - Unit - I
3.ROTARY IC ENGINE3.ROTARY IC ENGINE
February 5, 2015 Kinematics of Machinery - Unit - I 52
February 5, 2015 53Kinematics of Machinery - Unit - I
February 5, 2015 54Kinematics of Machinery - Unit - I
4.Crank and Slotted Lever Mechanism4.Crank and Slotted Lever Mechanism(Quick-Return Motion Mechanism) (Quick-Return Motion Mechanism)
February 5, 2015 55Kinematics of Machinery - Unit - I
Basic Quick-ReturnBasic Quick-Return
February 5, 2015 56Kinematics of Machinery - Unit - I
Quick-Return IN SHAPER M/CQuick-Return IN SHAPER M/C
February 5, 2015 57Kinematics of Machinery - Unit - I
February 5, 2015 58Kinematics of Machinery - Unit - I
WHIT WORTH QUICK-WHIT WORTH QUICK-RETURNRETURN
February 5, 2015 59Kinematics of Machinery - Unit - I
February 5, 2015 60Kinematics of Machinery - Unit - I
3.Double Slider Crank3.Double Slider CrankINVERSIONSINVERSIONS
February 5, 2015 61Kinematics of Machinery - Unit - I
ELLIPTICAL TRAMMELELLIPTICAL TRAMMEL
February 5, 2015 62Kinematics of Machinery - Unit - I
February 5, 2015 63Kinematics of Machinery - Unit - I
OLD HAMS COUPLINGOLD HAMS COUPLING
February 5, 2015 64Kinematics of Machinery - Unit - I
February 5, 2015 65Kinematics of Machinery - Unit - I
February 5, 2015 66Kinematics of Machinery - Unit - I
February 5, 2015 67Kinematics of Machinery - Unit - I
February 5, 2015 68Kinematics of Machinery - Unit - I
February 5, 2015 69Kinematics of Machinery - Unit - I
1. FOUR BAR CHAIN1. FOUR BAR CHAIN
(link 1) frame(link 1) frame (link 2) crank(link 2) crank (link 3) coupler (link 3) coupler (link 4) rocker (link 4) rocker
February 5, 2015 70Kinematics of Machinery - Unit - I
INVERSIONS OF FOUR BAR CHAININVERSIONS OF FOUR BAR CHAINFix link 1& 3. Crank-rocker Fix link 1& 3. Crank-rocker
or Crank-Leveror Crank-Lever
mechanism mechanism
Fix link 2. Drag link Fix link 2. Drag link
or Double Crank or Double Crank
mechanism mechanism
Fix link 4. Double rocker Fix link 4. Double rocker
mechanismmechanism
Pantograph Pantograph
February 5, 2015 71Kinematics of Machinery - Unit - I
APPLICATIONAPPLICATIONlink-1 fixed-link-1 fixed-
CRANK-ROCKER MECHANISMCRANK-ROCKER MECHANISM OSCILLATORY MOTIONOSCILLATORY MOTION
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CRANK-ROCKER CRANK-ROCKER MECHANISMMECHANISM
February 5, 2015 73Kinematics of Machinery - Unit - I
Link 2 Fixed- DRAG LINK Link 2 Fixed- DRAG LINK MECHANISMMECHANISM
February 5, 2015 74Kinematics of Machinery - Unit - I
Locomotive Wheel - DOUBLE Locomotive Wheel - DOUBLE CRANK MECHANISMCRANK MECHANISM
February 5, 2015 75Kinematics of Machinery - Unit - I
2.SLIDER CRANK CHAIN2.SLIDER CRANK CHAINLink1=GroundLink1=GroundLink2=CrankLink2=Crank
Link3=ConnectingRod Link3=ConnectingRod Link4=SliderLink4=Slider
February 5, 2015 76Kinematics of Machinery - Unit - I
lnversions of slider crank chainlnversions of slider crank chain
(a)(a) crank fixed (b) connecting rod fixed (c) slider fixedcrank fixed (b) connecting rod fixed (c) slider fixed
Link 2 fixedLink 2 fixed Link 3 fixed Link 3 fixed Link 4 fixed Link 4 fixed
February 5, 2015 77Kinematics of Machinery - Unit - I
ApplicationApplicationInversion II – Link 2 Crank fixed Inversion II – Link 2 Crank fixed
Whitworth quick return motion mechanismWhitworth quick return motion mechanism
2
1
2
2
ˆ
ˆ
θθ
=′′′′′′
=BoB
BoB
urnstrokeTimeforret
wardstrokeTimeforfor
February 5, 2015 78Kinematics of Machinery - Unit - I
Quick return motion mechanismsQuick return motion mechanisms
Drag link mechanismDrag link mechanism
12
21
ˆ
ˆ
BAB
BAB
urnstrokeTimeforret
wardstrokeTimeforfor =
February 5, 2015 79Kinematics of Machinery - Unit - I
Rotary engine– II inversion of slider crank Rotary engine– II inversion of slider crank mechanism. (crank fixed)mechanism. (crank fixed)
February 5, 2015 80Kinematics of Machinery - Unit - I
ApplicationApplicationInversion III -Link 3 Connecting rod fixed Inversion III -Link 3 Connecting rod fixed
Crank and slotted lever quick return mechanismCrank and slotted lever quick return mechanism
2
1
2
2
ˆ
ˆ
θθ
=′′′′′′
=BoB
BoB
urnstrokeTimeforret
wardstrokeTimeforfor
February 5, 2015 Kinematics of Machinery - Unit - I 81
Crank and slotted lever quick return Crank and slotted lever quick return motion mechanismmotion mechanism
February 5, 2015 82Kinematics of Machinery - Unit - I
Crank and slotted lever quick return motion Crank and slotted lever quick return motion mechanismmechanism
February 5, 2015 83Kinematics of Machinery - Unit - I
Application of Crank and slotted lever quick Application of Crank and slotted lever quick return motion mechanismreturn motion mechanism
February 5, 2015 84Kinematics of Machinery - Unit - I
Oscillating cylinder engine–III inversion of Oscillating cylinder engine–III inversion of slider crank mechanism (connecting rod fixed)slider crank mechanism (connecting rod fixed)
February 5, 2015 85Kinematics of Machinery - Unit - I
ApplicationApplicationInversion IV – Link 4 Slider fixed Inversion IV – Link 4 Slider fixed Pendulum pump or bull enginePendulum pump or bull engine
February 5, 2015 86Kinematics of Machinery - Unit - I
3. DOUBLE SLIDER CRANK 3. DOUBLE SLIDER CRANK CHAINCHAIN
It is a kinematic chain consisting of two It is a kinematic chain consisting of two turning pairs and two sliding pairs. turning pairs and two sliding pairs.
Link 1 Frame Link 1 Frame
Link 2 Slider -ILink 2 Slider -I
Link 3 CouplerLink 3 Coupler
Link 4 Slider - IILink 4 Slider - II
February 5, 2015 87Kinematics of Machinery - Unit - I
Inversion I – Frame FixedInversion I – Frame FixedDouble slider crank mechanismDouble slider crank mechanism
1sincos 22
22
=+=
+
θθp
y
q
x
1sincos 22
22
=+=
+
θθp
y
q
x
Elliptical trammelAC = p and BC = q, then, x = q.cosθ and y = p.sinθ.Rearranging,
February 5, 2015 88Kinematics of Machinery - Unit - I
Inversion II – Slider - I FixedInversion II – Slider - I Fixed SCOTCH –YOKE MECHANISMSCOTCH –YOKE MECHANISM
Turning pairs –1&2, 2&3; Sliding pairs – 3&4, Turning pairs –1&2, 2&3; Sliding pairs – 3&4, 4&1 4&1
February 5, 2015 89Kinematics of Machinery - Unit - I
Inversion III – Coupler FixedInversion III – Coupler Fixed OLDHAM COUPLINGOLDHAM COUPLING
February 5, 2015 90Kinematics of Machinery - Unit - I
Other MechanismsOther Mechanisms1.Straight line motion mechanisms1.Straight line motion mechanisms
Condition for perfect steeringCondition for perfect steeringLocus of pt.C Locus of pt.C will be a will be a
straight line, ┴ to AE if, straight line, ┴ to AE if,
is constant.is constant.
Proof:Proof:
ACAB×
..,
.
constACifABconstAE
constbutADAD
ACABAE
AE
AB
AC
AD
ABDAEC
=×=∴=
×=∴
=∴
∆≡∆
February 5, 2015 91Kinematics of Machinery - Unit - I
1.a) Peaucellier mechanism1.a) Peaucellier mechanism
February 5, 2015 92Kinematics of Machinery - Unit - I
1.b) Robert’s mechanism1.b) Robert’s mechanism
February 5, 2015 93Kinematics of Machinery - Unit - I
1.c) Pantograph1.c) Pantograph
February 5, 2015 94Kinematics of Machinery - Unit - I
2.Indexing Mechanism2.Indexing Mechanism
Geneva wheel mechanismGeneva wheel mechanism
February 5, 2015 95Kinematics of Machinery - Unit - I
3.Ratchets and Escapements3.Ratchets and Escapements
Ratchet and pawl mechanismRatchet and pawl mechanism
February 5, 2015 96Kinematics of Machinery - Unit - I
Application of Ratchet Pawl mechanismApplication of Ratchet Pawl mechanism
February 5, 2015 97Kinematics of Machinery - Unit - I
4. 4. Toggle mechanismToggle mechanism
Considering the Considering the equilibrium condition of equilibrium condition of slider 6, slider 6,
For small angles of For small angles of αα, F is , F is much smaller than P.much smaller than P.
α
α
tan2
2tan
PFP
F
=∴
=
February 5, 2015 98Kinematics of Machinery - Unit - I
5.Hooke’s joint5.Hooke’s joint
February 5, 2015 Kinematics of Machinery - Unit - I 99
Hooke’s jointHooke’s joint
February 5, 2015 100Kinematics of Machinery - Unit - I
6.Steering gear mechanism6.Steering gear mechanism
Condition for perfect steeringCondition for perfect steering
February 5, 2015 101Kinematics of Machinery - Unit - I
Ackermann steering gear mechanismAckermann steering gear mechanism
February 5, 2015 102Kinematics of Machinery - Unit - I
Mechanical Mechanical AdvantageAdvantage Mechanical Advantage Mechanical Advantage
of the Mechanism at of the Mechanism at angle a2 = 0angle a2 = 000 or 180 or 18000
Extreme position of the Extreme position of the linkage is known as linkage is known as toggle positions.toggle positions.
February 5, 2015 103Kinematics of Machinery - Unit - I
Transmission Transmission AngleAngleθθ = a1=Crank Angle = a1=Crank Angle
γγ = a2 =Angle between = a2 =Angle between crank and Couplercrank and Coupler
μμ = a3 =Transmission angle = a3 =Transmission angle
Cosine LawCosine Law
aa22 + d + d2 2 -2ad cos -2ad cos θθ = =
bb22 + c + c22 -2 bc cos -2 bc cos μμ
Where a=AD, b=CD,Where a=AD, b=CD,
c=BC, d=ABc=BC, d=AB
Determine Determine μμ..
February 5, 2015 104Kinematics of Machinery - Unit - I
Design of Design of MechanismMechanism
1.Slider – Crank Mechanism1.Slider – Crank MechanismLink Lengths, Stroke Length, Link Lengths, Stroke Length, Crank Angle specified. Crank Angle specified.
2.Offset Quick Return 2.Offset Quick Return MechanismMechanismLink Lengths, Stroke Length, Link Lengths, Stroke Length, Crank Angle, Time Ratio Crank Angle, Time Ratio specified.specified.
3.Four Bar Mechanism – 3.Four Bar Mechanism – Crank Rocker MechanismCrank Rocker MechanismLink Lengths and Rocker Link Lengths and Rocker angle Specified.angle Specified.
February 5, 2015 105Kinematics of Machinery - Unit - I
ALL THE BESTALL THE BEST