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GANDHINAGAR INSTITUTE OF TECHNOLOGYMechanical Department

B.E Sem. 4[C]

Machine Design & Industrial DraftingEccentric Loading

Cotter & Knuckle JointLever

Presented By :

•Nirav Patel (130120119160) Neel Patel (130120119157) •Nishant Patel (130120119162) Ravi Patel (130120119167)

Contents Cotter Joint Knuckle Joint Design & analysis of Lever Cranked

Cotter joint

Cotter Joint

TENSION FAILURE

SHEAR FAILURE

F

F

BEARING FAILURE

Cotter joint

Knuckle Joint

Knuckle joint Two or more rods subjected to tensile and compressive forces are fastened togetherTheir axes are not in alignments but meet in a point

The joint allows a small angular moment of one rod relative to another

It can be easily connected and disconnectedApplications: Elevator chains, valve rods, etc

Knuckle joint

Lever

LEVERLevers are one of basic tools that were probably used in

prehistoric times. It is assumed that in ancient Egypt, constructors used the lever to move and uplift obelisks weighing more than 100 tons.

Lever is a simple machine that makes work easier to use; it involves moving a load around a pivot using a minimum force.

A lever amplifies an input force to provide a greater output force,which is said to provide leverage.

The levers are used to lift heavy weight with least amount of effort.

Parts of a Lever System

A. Lever

E. Effort Arm

B. Fulcrum

H. Resistance Arm

F. Effort Force

C. Resistance Distance D. Resistance Force

G. Effort Distance

Entire board

CD

H

GF

B

A

E

EFFORT

FULCRUM

RESISTANCE

FIRST CLASS LEVER

A first-class lever is a lever in which the fulcrum is located in between the input effort and the output load.

EFFORT

RESISTANCE

FULCRUM

SECOND CLASS LEVER

A second-class lever is a lever in which the resistance is located in between the input effort and the fulcrum.

EFFORT

RESISTANCE

FULCRUM

THIRD CLASS LEVER

A third-class lever is a lever in which the effort is located in between the input resistance and the fulcrum.

F

E

RTHIRD CLASS LEVER

E

F

R

FIRST CLASS LEVER

ER

FSECOND CLASS LEVER

Mechanical Advantage Mechanical Advantage is the ratio between the load and effort.

Mechanical Advantage Mechanical Advantage deals only with forces.

Mechanical Advantage > 1 > 1 means that the output force will be greater than the input force.

(But the input distance will need to be greater than the output distance.)

First and Second class levers have a positive mechanical advantage.

Third class levers have a mechanical disadvantagedisadvantage, , meaning you use more force that the force of the load you lift.

THANK YOU