inversion of mechanisms: theory of machines with videos
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Mechanics of Machinery Naseel Ibnu AzeezAssistant Professor, [email protected]
LinkKinematic PairLinkageMechanism4-Bar MechanismSlider-Crank MechanismDouble Slider-Crank
4 Bar Mechanism
Grashof conditionThe Grashof condition for a four-bar linkage states:If the sum of the shortest and longest link of a planar quadrilateral linkage is less than or equal to the sum of the remaining two links, then the shortest link can rotate fully with respect to a neighbouring link.In other words, the condition is satisfied ifS+LP+Q whereSis the shortest link,Lis the longest PandQ are the other links.
Parallelogram 4-Bar MechanismFirst Inversion
Beam Engine
Second Inversion
Watt Mechanism
The central moving point of the linkage is constrained to travel on an approximation to a straight line.Third Inversion
PantographsApantographis a mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a second pen.
Fourth Inversion
Slider-Crank Mechanism
First Inversion
Reciprocating Engine or Compressor
Second Inversion
Hand Pump
Third Inversion
a) Cylinder Engine
b)Crank and Slotted lever Quick Return Mechanism
Fourth Inversion
a) Whitworth Quick Return Mechanism
b) Rotary Engine or Gnome
Double-Slider Crank Mechanism
First Inversion
Elliptical Trammel
Second Inversion
Scotch Yoke Mechanism
Third Inversion
Oldhams Coupling
4 Bar MechanismSlider-Crank MechanismDouble-Slider Crank1st2nd3rd4thParallelogram MechanismBeam EnginePantographWatt Mechanism1st2nd3rd4thPiston-Cylinder SystemHand PumpCylinder Engine & Quick Return Mechanism Whitworth Quick Return Mechanism & Rotary Engine1st2nd3rdElliptical TrammelScotch-Yoke MechanismOldhams Coupling