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SRI MUTHUKUMARAN INSTITUTE OFTECHNOLOGY
V.NarendranathT.PrasathP.PramanayagamE.Ravikumar
Double Side Compressor usingScotch Yoke Mechanism
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What is
Mechanism?
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In mechanical construction, the means
employed to transmit and modifymotion in a machine or any assemblage
of mechanical parts. The chiefcharacteristic of the mechanism of amachine is that all members have
constrained motion; i.e.,the parts canmove only in a determinate manner
relative to one another.
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This linkage is being called by a Scotsman
in 1869 a "crank and slot-headed slidingrodBut now it is known as a Scotch yokebecause, in America at least, a "Scotch"
was a slotted bar that was slipped undera collar on a string of well-drilling tools tosupport them while a section was being
added In 1940 Russell Bourke applied this
mechanism to the internal combustionengine called Bourke 30 engine
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Mechanism for converting the
linear motion of a slider into
rotational motion or vice-versa.
The Scotch Yoke performs muchthe same function as the simple
crank.
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PARTS OF SCOTCH YOKE
CrankSlider & Yoke
FrameFrame
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High torqueoutput with a smallcylinder size.
Fewer moving parts.
In an engine application, eliminationof joint typically served by a wrist pin,and near elimination of piston skirt
and cylinder scuffing, as side loadingof piston due to sine of connectingrod angle is eliminated.
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Rapid wear of the slot in the yoke caused bysliding friction and high contact pressures.More heat loss during combustion due to
extended dwell at top dead center off sets
any constant volume combustionimprovements in real engines.
Lesser percentage of the time spent at
bottom dead center reducing blow downtime for two stroke engines, when comparedwith a conventional piston and crankshaftmechanism.