ANNA UNIVERSITY : CHENNAI 600 025

BONAFIDE CERTIFICATE

Certified that this project report “Alternate transmission system” is the bonafide work of “ Rohith Kumar.M (111711114123), Rajkiran.V (111711114117),Sasidaran.K (111711114129), Sathya Lenin.E.A.R.C (111711114130)” carried out the project word under my

supervision.

SIGNATURE SIGNATURE

Prof. Dr. K. R. SENTHIL KUMAR, M.E, Ph.D. Mr.D.Jayabalan, M.E.,

HEAD OF THE DEPARTMENT SUPERVISOR

Department of Mechanical Engg, Department of Mechanical Engg,R.M.K. Engineering College, R.M.K. Engineering College,Kavaraipettai, Chennai-601206. Kavaraipettai, Chennai-601206.

Submitted for the project viva voce held on ……………. at R.M.K. Engineering College, Kavaraipettai, Chennai-601 206.

INTERNAL EXAMINER EXTERNAL EXAMINER

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ACKNOWLEDGEMENT

We would express our gratitude to our beloved chairman SHRI R. S. MUNIRATHINAM, R.M.K. Engineering College, Kavaraipettai, Chennai – 601206 for having arranged to do this project.

We express our sincere thanks to our beloved guide Mr.D.Jayabalan, M.E., (PhD), for his valuable guidance and encouragement for finishing the project successfully.

We would also like to express our sincere thanks to our beloved Principal Dr. ELWIN CHANDRA MONIE and Head of the Department Prof. Dr. K. R. SENTHIL KUMAR, for having made for guidance and counseling throughout this project work.

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Abstract

The main objective of our work “Alternate transmission system “is to design a chain drive which can rotate under different axis .In a conventional chain drive system, when the driven’s angle is changed ,the drive’s angle must be changed correspondingly to achieve smooth transmission In our project “Design and analysis of alternate transmission system” we overcome this disability by achieving transmission even when the driven’s angle is changed

This has a wide range of application were machine containing multi drives can be replaced with single drive. In this design we use a conical tooth which slides and locks automatically when the driven’s axis is changed. Each chain section consists of a hub connected to another hub with two pins on one side and with teeth section on the other side. In this project we use two software, one for designing and drafting and another for analysis.

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TABLE OF CONTENTS

CHAPTER NO. TITLE PAGE NO.

ABSTRACT i

1.INTRODUCTION 1

COMPONENTS

2.HUB 2

2.1.MECHANICS 2

2.2. ADVANTAGES AND DISADVANTAGES

2.3.USES 3

2.3.1.Engine starters 3

2.3.2.Bicycle

2.3.3.Helicopters

2.3.4.History

3.PIN 1

3.1.HISTORY

3.2.COMMON DESIGNS

3.2.1.Angular Contact

3.2.2.Axial

3.2.3.Deep-groove

3.3.LUBRICATION

3.4.APPLICATION

4.PIN2

4.1.APPLICATION

4.2.HISTORY

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4.3.PHYSICS

4.4.RIMMED

5.SPROKET

5.1.TRANSPORATION

5.2.TRACKED VEHICLES

5.3.FILM AND PAPER

6.CONICAL TOOTH

6.1. HISTORY

6.2.CHAINS VERSUS BELTS

6.3.USE IN VEHICLES

6.3.1.Bicycles

6.3.2.Automobiles

6.3.2.1.Transmitting power to wheels

8.DESIGNING

8.1.DESCRIPTION

8.2.COMMUTATION

8.3.EXCITATION

8.4.MODERN USES

9. ANALYSIS

9.1.PROCESSES

9.1.1.ARC

9.1.2.POWER SUPPLIES

10.TURNING

10.1.TURNING OPERATIONS

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10.1.1.Turning

10.1.1.1.Tapered Turning

10.1.1.2.Spherical Generation

10.1.1.3.Hard Turning

11.DESIGN AND FABRICATION

12.WORKING

13.ADVANTAGES AND DISADVANTAGES

14.SPECIFICATION AND CALCULATION

15.COST ANALYSIS

16.CONCLUSION

1.INTRODUCTION

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The Introduction of our work “Dynamo Street Lamps” includes,

Dynamo Street lamps consists of components such as Flywheel,Freewheel,Ballbearings,Gear sprockets,Chain drives,Dynamo,casings,wood plate,steel plates,sprockets,springs which compress.when the Rack directions which makes the freewheel to rotate in positive directions which makes shaft also to rotate in positive direction which tends the sprockets to rotate and also makes Dynamo to produce current which can be measured by ammeter.

2.FREEWHEEL

Freewheel mechanism

Ratcheting freewheel mechanism (van Anden, 1869)

In mechanical or automotive engineering, a freewheel or overrunning clutch is a

device in a transmission that disengages the driveshaft from the driven shaft when the

driven shaft rotates faster than the driveshaft. An overdrive is mistakenly called a

freewheel, but is otherwise unrelated.`

The condition of a driven shaft spinning faster than its driveshaft exists in

most bicycles when the rider holds his or her feet still, no longer pushing the pedals. In

a fixed-gear bicycle, without a freewheel, the rear wheel would drive the pedals around.

An analogous condition exists in an automobile with a manual transmission going down

hill or any situation where the driver takes his or her foot off the gas pedal, closing

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the throttle; the wheels want to drive the engine, possibly at a higher RPM. In a two-

stroke engine this can be a catastrophic situation: as many two stroke engines depend

on a fuel/oil mixture for lubrication, a shortage of fuel to the engine would result in a

shortage of oil in the cylinders, and the pistons would seize after a very short time

causing extensive engine damage. Saab used a freewheel system in their two-stroke

models for this reason and maintained it in the Saab 96V4 and early Saab 99 for

better fuel efficiency.

2.1Mechanics

The simplest freewheel device consists of two saw-toothed, spring-loaded discs

pressing against each other with the toothed sides together, somewhat like a ratchet.

Rotating in one direction, the saw teeth of the drive disc lock with the teeth of the driven

disc, making it rotate at the same speed. If the drive disc slows down or stops rotating,

the teeth of the driven disc slip over the drive disc teeth and continue rotating, producing

a characteristic clicking sound proportionate to the speed difference of the driven gear

relative to that of the (slower) driving gear.

A more sophisticated and rugged design has spring-loaded steel rollers inside a driven

cylinder. Rotating in one direction, the rollers lock with the cylinder making it rotate in

unison. Rotating slower, or in the other direction, the steel rollers just slip inside the

cylinder.

Most bicycle freewheels use an internally step-toothed drum with two or more spring-

loaded, hardened steel pawls to transmit the load. More pawls help spread the wear

and give greater reliability although, unless the device is made to tolerances not

normally found in bicycle components, simultaneous engagement of more than two

pawls is rarely achieved.

2.2Advantages and disadvantages

By its nature, a freewheel mechanism acts as an automatic clutch, making it possible to

change gears in a manual gearbox, either up- or downshifting, without depressing the

clutch pedal, limiting the use of the manual clutch to starting from standstill or stopping.

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The Saab freewheel can be engaged or disengaged by the driver by respectively

pushing or pulling a lever. This will lock or unlock the main shaft with the freewheel hub.

A freewheel also produces slightly better fuel economy on carbureted engines (without

fuel turn-off on engine brake) and less wear on the manual clutch, but leads to more

wear on the brakes as there is no longer any ability to perform engine braking. This may

make freewheel transmissions dangerous for use on trucks and automobiles driven in

mountainous regions, as prolonged and continuous application of brakes to limit vehicle

speed soon leads to brake-system overheating followed shortly by total failure.

2.3Uses

2.3.1Engine starters

A freewheel assembly is also widely used on engine starters as a kind of protective

device. Starter motors usually need to spin at 3,000 RPM to get the engine to turn over.

When the key is held in the start position for any amount of time after the engine has

started, the starter cannot spin fast enough to keep up with the flywheel. Because of the

extreme gear ratio between starter gear and flywheel (about 15 or 20:1) it would spin

the starter armature at dangerously high speeds, causing an explosion when the

centripetal force acting on the copper coils wound in the armature can no longer resist

the outward force acting on them. In starters without the freewheel or overrun clutch this

would be a major problem because, with the flywheel spinning at about 1,000 RPM at

idle, the starter, if engaged with the flywheel, would be forced to spin between 15,000

and 20,000 RPM. Once the engine has turned over and is running, the overrun clutch

will release the starter from the flywheel and prevent the gears from re-meshing (as in

an accidental turning of the ignition key) while the engine is running. A freewheel clutch

is now used in many motorcycles with an electric starter motor. It is used as a

replacement for the Bendix drive used on most auto starters because it reduces the

electrical needs of the starting system.

2.3.2Bicycles

In the older style of bicycle, where the free wheel mechanism is included in the gear

assembly, the system is called a free wheel, whereas the newer style, in which the

freewheel mechanism is in the hub, is called a free hub.

2.3.3Helicopters

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Freewheels are also used in rotorcraft. As a bicycle's wheels need to be able to rotate

faster than the pedals, so do a rotorcraft's blades need to be able to spin faster than its

drive engines. This is especially important in the event of an engine failure where a free

wheel in the main transmission allows the main and tail rotor systems to continue to

spin independent of the drive system. This provides for continued flight control and

an autorotation landing.

2.4History

In 1869, William Van Anden invented the freewheel for the bicycle. His design placed a

ratchet device in the hub of the front wheel, which allowed the rider to propel himself

forward without pedaling constantly. Initially, bicycle enthusiasts rejected the idea of a

free wheel because they believed it would complicate the mechanical functions of the

bicycle. Bicycle enthusiasts believed that the bicycle was supposed to remain as simple

as possible without any additional mechanisms, such as the free wheel.

Due to the lack of popularity for the free wheel, it was not continuously re-engineered to

be more useful for several decades. In 1899, American manufacturers developed the

“coaster brake,” which allowed riders to brake by pedaling backwards and included the

freewheel mechanism. At the turn of the century, bicycle manufacturers within Europe

and America included the free wheel mechanism in a majority of their bicycles but now

the freewheel was incorporated in the rear sprocket of a bicycle unlike Van Anden’s

initial design.

In 1924, the French bicycle company, Le Cyclo, introduced a gear-shifting bicycle with a

two sprocket freewheel, which would allow riders to go uphill with more ease. In the late

1920s, Le Cyclo began using both front and rear derailleurs in combination with a

double chain ring giving the bicycle twice as many gears. In the early 1930s, Le Cyclo

invented a four sprocket freewheel and several years later the company combined the

four sprocket freewheel with a triple chain ring giving the bicycle twelve gears.

In the 1970s, Japanese manufacturers introduced their own version of the derailleurs.

The Japanese bicycle company, SunTour introduced the slant parallelogram derailleurs

which were tilted back allowing the cage to be located farther away from the freewheel

than the European version. This allowed for the chain to shift more smoothly from gear

to gear. The Japanese version of the derailleur became the standard and still is today.

3.BALL BEARING

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Ball (bearing)

Working principle for a ball bearing

A 4 point angular contact ball bearing

A ball bearing with a semi transparent cage

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Wingquist's and SKF's self-aligning ball bearing

A ball bearing is a type of rolling-element bearing that uses balls to maintain the

separation between the bearing races.

The purpose of a ball bearing is to reduce rotational friction and

support radial and axial loads. It achieves this by using at least two races to contain the

balls and transmit the loads through the balls. In most applications, one race is

stationary and the other is attached to the rotating assembly (e.g., a hub or shaft). As

one of the bearing races rotates it causes the balls to rotate as well. Because the balls

are rolling they have a much lower coefficient of friction than if two flat surfaces were

sliding against each other.

Ball bearings tend to have lower load capacity for their size than other kinds of rolling-

element bearings due to the smaller contact area between the balls and races.

However, they can tolerate some misalignment of the inner and outer races.

3.1History

Although roller bearings had been developed since ancient times, the first modern

recorded patent on ball bearings was awarded to Philip Vaughan, a Welsh inventor

and ironmaster who created the first design for a ball bearing in Carmarthen in 1794.

His was the first modern ball-bearing design, with the ball running along a groove in the

axle assembly.

Jules Suriray, a Parisian bicycle mechanic, designed the first radial style ball bearing in

1869, which was then fitted to the winning bicycle ridden by James Moore in the world's

first bicycle road race, Paris-Rouen, in November 1869.

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3.2Common designs

There are several common designs of ball bearing, each offering various trade-offs.

They can be made from many different materials, including: stainless steel, chrome

steel, and ceramic (silicon nitride (Si3N4)). A hybrid ball bearing is a bearing with ceramic

balls and races of metal.

3.2.1Angular contact

An angular contact ball bearing uses axially asymmetric races. An axial load passes in a

straight line through the bearing, whereas a radial load takes an oblique path that tends

to want to separate the races axially. So the angle of contact on the inner race is the

same as that on the outer race. Angular contact bearings better support "combined

loads" (loading in both the radial and axial directions) and the contact angle of the

bearing should be matched to the relative proportions of each. The larger the contact

angle (typically in the range 10 to 45 degrees), the higher the axial load supported, but

the lower the radial load. In high speed applications, such as turbines, jet engines, and

dentistry equipment, the centrifugal forces generated by the balls changes the contact

angle at the inner and outer race. Ceramics such as silicon nitride are now regularly

used in such applications due to their low density (40% of steel). These materials

significantly reduce centrifugal force and function well in high temperature

environments. They also tend to wear in a similar way to bearing steel—rather than

cracking or shattering like glass or porcelain.

Most bicycles use angular-contact bearings in the headsets because the forces on

these bearings are in both the radial and axial direction.

3.2.2Axial

An axial ball bearing uses side-by-side races. An axial load is transmitted directly

through the bearing, while a radial load is poorly supported and tends to separate the

races,so that a larger radial load is likely to damage the bearing.

3.2.3Deep-groove

In a deep-groove radial bearing, the race dimensions are close to the dimensions of the

balls that run in it. Deep-groove bearings can support higher loads.

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3.3Lubrication

For a bearing to operate properly, it needs to be lubricated. In most cases the lubricant

is based on elastohydrodynamic effect (by oil or grease) but working at extreme

temperatures dry lubricated bearings are also available.

For a bearing to have its nominal lifespan at its nominal maximum load, it must be

lubricated with a lubricant (oil or grease) that has at least the minimum dynamic

viscosity (usually denoted with the Greek letter  ) recommended for that bearing.

The recommended dynamic viscosity is inversely proportional to diameter of bearing.

The recommended dynamic viscosity decreases with rotating frequency. As a rough

indication: for less than 3000 RPM, recommended viscosity increases with factor 6 for a

factor 10 decrease in speed, and for more than 3000 RPM, recommended viscosity

decreases with factor 3 for a factor 10 increase in speed.

For a bearing where average of outer diameter of bearing and diameter of axle hole

is 50 mm, and that is rotating at 3000 RPM, recommended dynamic viscosity is 12

mm²/s.

Note that dynamic viscosity of oil varies strongly with temperature: a temperature

increase of 50–70 °C causes the viscosity to decrease by factor 10.

If the viscosity of lubricant is higher than recommended, lifespan of bearing increases,

roughly proportional to square root of viscosity. If the viscosity of the lubricant is lower

than recommended, the lifespan of the bearing decreases, and by how much depends

on which type of oil being used. For oils with EP ('extreme pressure') additives, the

lifespan is proportional to the square root of dynamic viscosity, just as it was for too high

viscosity, while for ordinary oil's lifespan is proportional to the square of the viscosity if a

lower-than-recommended viscosity is used.

Lubrication can be done with a grease, which has advantages that grease is normally

held within the bearing releasing the lubricant oil as it is compressed by the balls. It

provides a protective barrier for the bearing metal from the environment, but has

disadvantages that this grease must be replaced periodically, and maximum load of

bearing decreases (because if bearing gets too warm, grease melts and runs out of

bearing). Time between grease replacements decreases very strongly with diameter of

bearing: for a 40 mm bearing, grease should be replaced every 5000 working hours,

while for a 100 mm bearing it should be replaced every 500 working hours.

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Lubrication can also be done with an oil, which has advantage of higher maximum load,

but needs some way to keep oil in bearing, as it normally tends to run out of it. For oil

lubrication it is recommended that for applications where oil does not become warmer

than 50 °C, oil should be replaced once a year, while for applications where oil does not

become warmer than 100 °C, oil should be replaced 4 times per year. For car engines,

oil becomes 100 °C but the engine has an oil filter to continually improve oil quality;

therefore, the oil is usually changed less frequently than the oil in bearings.

3.4Applications

In general, ball bearings are used in most applications that involve moving parts. Some

of these applications have specific features and requirements:

Hard drive bearings used to be highly spherical, and were said to be the best

spherical manufactured shapes, but this is no longer true, and more and more are

being replaced with fluid bearings.

German ball bearing factories were often a target of allied aerial bombings during

World War II; such was the importance of the ball bearing to the German war

industry.

In horology, the company Jean Lassale designed a watch movement that used ball

bearings to reduce the thickness of the movement. Using 0.20 mm balls, the Calibre

1200 was only 1.2 mm thick, which still is the thinnest mechanical watch movement.

Aerospace bearings are used in many applications on commercial, private and

military aircraft including pulleys, gearboxes and jet engine shafts. Materials include

M50 tool steel (AMS6491), Carbon chrome steel (AMS6444), the corrosion resistant

AMS5930, 440C stainless steel, silicon nitride (ceramic) and titanium carbide-coated

440C.

Skateboard wheels each contain two bearings, which are subject to both axial and

radial time-varying loads. Most commonly bearing 608-2Z is used (a deep groove

ball bearing from series 60 with 8 mm bore diameter)

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4.FLYWHEEL

An industrial flywheel.

A flywheel is a rotating mechanical device that is used to store rotational energy.

Flywheels have a significant moment of inertiaand thus resist changes in rotational

speed. The amount of energy stored in a flywheel is proportional to the square of

its rotational speed. Energy is transferred to a flywheel by applying torque to it, thereby

increasing its rotational speed, and hence its stored energy. Conversely, a flywheel

releases stored energy by applying torque to a mechanical load, thereby decreasing its

rotational speed.

Common uses of a flywheel include:

Providing continuous energy when the energy source is discontinuous. For example,

flywheels are used in reciprocating enginesbecause the energy source, torque from

the engine, is intermittent.

Delivering energy at rates beyond the ability of a continuous energy source. This is

achieved by collecting energy in the flywheel over time and then releasing the

energy quickly, at rates that exceed the abilities of the energy source.

Controlling the orientation of a mechanical system. In such applications, the angular

momentum of a flywheel is purposely transferred to a load when energy is

transferred to or from the flywheel.

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Flywheels are typically made of steel and rotate on conventional bearings; these are

generally limited to a revolution rate of a few thousand RPM. Some modern flywheels

are made of carbon fiber materials and employ magnetic bearings, enabling them to

revolve at speeds up to 60,000 RPM.

Carbon-composite flywheel batteries have recently been manufactured and are proving

to be viable in real-world tests on mainstream cars. Additionally, they are more eco-

friendly, as it is not necessary to take special measures in the disposal of them.

4.1Applications

A Landini tractor with exposed flywheel.

Flywheels are often used to provide continuous energy in systems where the energy

source is not continuous. In such cases, the flywheel stores energy when torque is

applied by the energy source, and it r eleases stored energy when the energy source is

not applying torque to it. For example, a flywheel is used to maintain constant angular

velocity of the crankshaft in a reciprocating engine. In this case, the flywheel—which is

mounted on the crankshaft—stores energy when torque is exerted on it by a

firing piston, and it releases energy to its mechanical loads when no piston is exerting

torque on it. Other examples of this are friction motors, which use flywheel energy to

power devices such as toy cars.

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Modern automobile engine flywheel

A flywheel may also be used to supply intermittent pulses of energy at transfer rates

that exceed the abilities of its energy source, or when such pulses would disrupt the

energy supply (e.g., public electric network). This is achieved by accumulating stored

energy in the flywheel over a period of time, at a rate that is compatible with the energy

source, and then releasing that energy at a much higher rate over a relatively short

time. For example, flywheels are used in riveting machines to store energy from the

motor and release it during the riveting operation.

The phenomenon of precession has to be considered when using flywheels in vehicles.

A rotating flywheel responds to any momentum that tends to change the direction of its

axis of rotation by a resulting precession rotation. A vehicle with a vertical-axis flywheel

would experience a lateral momentum when passing the top of a hill or the bottom of a

valley (roll momentum in response to a pitch change). Two counter-rotating flywheels

may be needed to eliminate this effect. This effect is leveraged in reaction wheels, a typ

e of flywheel employed in satellites in which the flywheel is used to orient the satellite's

instruments without thruster rockets.

4.2History

The principle of the flywheel is found in the Neolithic spindle and the potter's wheel.

The flywheel as a general mechanical device for equalizing the speed of rotation is,

according to the American medievalist Lynn White, recorded in the De diversibus

artibus (On various arts) of the German artisan Theophilus Presbyter (ca. 1070–1125)

who records applying the device in several of his machines.

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In the Industrial Revolution, James Watt contributed to the development of the flywheel

in the steam engine, and his contemporaryJames Pickard used a flywheel combined

with a crank to transform reciprocating into rotary motion.

4.3Physics

 

A flywheel with variable moment of inertia, conceived by Leonardo da Vinci.

A flywheel is a spinning wheel or disc with a fixed axle so that rotation is only about one

axis. Energy is stored in the rotor as kinetic energy, or more specifically, rotational

energy:

Where:

ω is the angular velocity, and

 is the moment of inertia of the mass about the center of rotation. The moment of

inertia is the measure of resistance to torqueapplied on a spinning object (i.e. the

higher the moment of inertia, the slower it will spin when a given force is applied).

The moment of inertia for a solid cylinder is  ,

for a thin-walled empty cylinder is  ,

and for a thick-walled empty cylinder is  ,

Where m denotes mass, and r denotes a radius.

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When calculating with SI units, the standards would be for mass, kilograms; for radius,

meters; and for angular velocity, radians per second. The resulting answer would be

injoules.

The amount of energy that can safely be stored in the rotor depends on the point at

which the rotor will warp or shatter. The hoop stress on the rotor is a major

consideration in the design of a flywheel energy storage system.

Where:

 is the tensile stress on the rim of the cylinder

 is the density of the cylinder

 is the radius of the cylinder, and

 is the angular velocity of the cylinder.

This formula can also be simplified using specific tensile strength and tangent velocity:

Where:

 is the specific tensile strength of the material

 is the tangent velocity of the rim.

Table of energy storage traits

Flywheel purpose, type

Geometric shape factor (k)

(unitless – varies with shape)

Mass(kg)

Diameter(cm)

Angular velocity(rpm)

Energy stored(MJ)

Energy stored(kWh)

Small battery 0.5 100 60 20,000 9.8 2.7

Regenerative braking in trains

0.5 3000 50 8,000 33.0 9.1

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Electric power backup[7] 0.5 600 50 30,000 92.0 26.0

4.4Rimmed

A rimmed flywheel has a rim, a hub, and spokes. The structure of a rimmed flywheel is

complex and, consequently, it may be difficult to compute its exact moment of inertia] A

rimmed flywheel can be more easily analysed by applying various simplifications. For

example:

Assume the spokes, shaft and hub have zero moments of inertia, and the flywheel's

moment of inertia is from the rim alone.

The lumped moments of inertia of spokes, hub and shaft may be estimated as a

percentage of the flywheel's moment of inertia, with the remainder from the rim, so

that 

For example, if the moments of inertia of hub, spokes and shaft are deemed negligible,

and the rim's thickness is very small compared to its mean radius ( ), the radius of

rotation of the rim is equal to its mean radius and thus:

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5.SPROKET

16 tooth sprocket. Do = Sprocket diameter. Dp = Pitch diameter

A sprocket and roller chain

A sprocket or sprocket-wheel is a profiled wheel with teeth, cogs, or even

sprockets that mesh with a chain,track or other perforated or indented material. The

name "sprocket" applies generally to any wheel upon which are radial projections that

engage a chain passing over it. It is distinguished from a gear in that sprockets are

never meshed together directly, and differs from a pulley in that sprockets have teeth

and pulleys are smooth.

Sprockets are used in bicycles, motorcycles, cars, tracked vehicles, and

other machinery either to transmit rotary motion between two shafts where gears are

unsuitable or to impart linear motion to a track, tape etc. Perhaps the most common

form of sprocket may be found in the bicycle, in which the pedal shaft carries a large

sprocket-wheel, which drives a chain, which, in turn, drives a small sprocket on the axle

of the rear wheel. Early automobiles were also largely driven by sprocket and chain

mechanism, a practice largely copied from bicycles.

Sprockets are of various designs, a maximum of efficiency being claimed for each by its

originator. Sprockets typically do not have a flange. Some sprockets used with timing

belts have flanges to keep the timing belt centered. Sprockets and chains are also used

for power transmission from one shaft to another where slippage is not admissible,

sprocket chains being used instead of belts or ropes and sprocket-wheels instead of

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pulleys. They can be run at high speed and some forms of chain are so constructed as

to be noiseless even at high speed.

5.1Transportation[edit]

In the case of bicycle chains, it is possible to modify the overall gear ratio of the chain

drive by varying the diameter (and therefore, the tooth count) of the sprockets on each

side of the chain. This is the basis of derailleur gears. A multi-speed bicycle, by

providing two or three different-sized driving sprockets and up to 11 (as of 2014)

different-sized driven sprockets, allows up to 30 different gear ratios. The resulting lower

gear ratios make the bike easier to pedal up hills while the higher gear ratios make the

bike more powerful to pedal on flats and downhills. In a similar way, manually changing

the sprockets on a motorcycle can change the characteristics of acceleration and

top speed by modifying the final drive gear ratio.

5.2Tracked vehicles[edit]

Tread drive sprocket of the Leclerc main battle tank (2006).

In the case of vehicles with caterpillar tracks the engine-driven toothed-wheel

transmitting motion to the tracks is known as the drive sprocket and may be positioned

at the front or back of the vehicle, or in some cases both. There may also be a third

sprocket, elevated, driving the track.

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5.3Film and paper[edit]

Moving picture mechanism from 1914. The sprocket wheels a, b, and c engage and

transport the film. a and b move with uniform velocity and c indexes each frame of the

film into place for projection.

Sprockets are used in the film transport mechanisms of movie projectors and movie

cameras. In this case, the sprocket wheels engage film perforations in the film stock.

Sprocket feed was also used for punched tape and is used for paperfeed to

some computer printers.

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6.CHAIN DRIVE

Roller chain andsprocket

Mack AC delivery truck at the Petersen Automotive Museum with chain drive visible

Chain drive is a way of transmitting mechanical power from one place to another. It is

often used to convey power to the wheels of a vehicle,

particularly bicycles and motorcycles. It is also used in a wide variety of machines

besides vehicles.

Most often, the power is conveyed by a roller chain, known as the drive

chain or transmission chain, passing over a sprocket gear, with the teeth of the gear

meshing with the holes in the links of the chain. The gear is turned, and this pulls the

chain putting mechanical force into the system. Another type of drive chain is the Morse

chain, invented by the Morse Chain Company of Ithaca, New York, USA. This has

inverted teeth.

Sometimes the power is output by simply rotating the chain, which can be used to lift or

drag objects. In other situations, a second gear is placed and the power is recovered by

attaching shafts or hubs to this gear. Though drive chains are often simple oval loops,

they can also go around corners by placing more than two gears along the chain; gears

that do not put power into the system or transmit it out are generally known as idler-

wheels. By varying the diameter of the input and output gears with respect to each

other, the gear ratio can be altered, so that, for example, the pedals of a bicycle can

spin all the way around more than once for every rotation of the gear that drives the

wheels.

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6.1History

Oldest known illustration of an endless power-transmitting chain drive, from Su Song's

book of 1092 describing his clock tower ofKaifeng

Sketch of roller chain by Leonardo da Vinci

The oldest known application of a chain drive appears in the Polybolos, a repeating

crossbow desc

ribed by the Greek engineer Philon of Byzantium (3rd century BC). Two flat-linked

chains were connected to a windlass, which by winding back and forth would

automatically fire the machine's arrows until its magazine was empty. Although the

device did not transmit power continuously since the chains "did not transmit power

from shaft to shaft", the Greek design marks the beginning of the history of the chain

drive since "no earlier instance of such a cam is known, and none as complex is known

until the 16th century. It is here that the flat-link chain, often attributed to Leonardo da

Vinci, actually made its first appearance."

The first continuous power-transmitting chain drive was depicted in the

written horological treatise of the Song Dynasty (960–1279) Chineseengineer Su

Song (1020-1101 AD), who used it to operate the armillary sphere of

his astronomical clock tower as well as the clock jack figurines presenting the time of

day by mechanically banging gongs and drums. The chain drive itself was given power

via the hydraulic works of Su's water clock tank and waterwheel, the latter which acted

as a large gear.

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6.2Chains versus belts[edit]

Roller chain and sprockets is a very efficient method of power transmission compared to

belts, with far less frictional loss.

Although chains can be made stronger than belts, their greater mass increases drive

train inertia.

Drive chains are most often made of metal, while belts are often rubber, plastic, or other

substances. Drive belts can slip unless they have teeth, which means that the output

side may not rotate at a precise speed, and some work gets lost to the friction of the belt

against its rollers. Teeth on toothed drive belts generally wear faster than links on

chains, but wear on rubber or plastic belts and their teeth is often easier to observe.

Conventional roller chain drives suffer the potential for vibration, as the effective radius

of action in a chain and sprocket combination constantly changes during revolution

("Chordal action"). If the chain moves at constant speed, then the shafts must

accelerate and decelerate constantly. If one sprocket rotates at a constant speed, then

the chain (and probably all other sprockets that it drives) must accelerate and

decelerate constantly. This is usually not an issue with many drive systems, however

most motorcycles are fitted with a rubber bushed rear wheel hub to virtually eliminate

this vibration issue. Toothed belt drives are designed to avoid this issue by operating at

a constant pitch radius.

Chains are often narrower than belts, and this can make it easier to shift them to larger

or smaller gears in order to vary the gear ratio. Multi-speed bicycles

withderailleurs make use of this. Also, the more positive meshing of a chain can make it

easier to build gears that can increase or shrink in diameter, again altering the gear

ratio.

Both can be used to move objects by attaching pockets, buckets, or frames to them;

chains are often used to move things vertically by holding them in frames, as in

industrial toasters, while belts are good at moving things horizontally in the form

of conveyor belts. It is not unusual for the systems to be used in combination; for

example the rollers that drive conveyor belts are themselves often driven by drive

chains.

Drive shafts are another common method used to move mechanical power around that

is sometimes evaluated in comparison to chain drive; in particular belt drive vs chain

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drive vs shaft drive is a key design decision for most motorcycles. Drive shafts tend to

be tougher and more reliable than chain drive, but the bevel gears have far more friction

than a chain. For this reason virtually all high performance motorcycles use chain drive,

with shaft driven arrangements generally used for non-sporting machines. Toothed belt

drives are used for some (non-sporting) models.

6.3Use in vehicles

6.3.1Bicycles

Chain drive was the main feature which differentiated the safety bicycle introduced in

1885, with its two equal-sized wheels, from the direct-drive penny-farthing or "high

wheeler" type of bicycle. The popularity of the chain-driven safety bicycle brought about

the demise of the penny-farthing, and is still a basic feature of bicycle design today.

6.3.2Automobiles

6.3.2.1Transmitting power to the wheels

Chain final drive, 1912 illustration

Chain drive was a popular power transmission system from the earliest days of

the automobile. It gained prominence as an alternative to the Système Panhard with its

rigid Hotchkiss driveshaft and universal joints.

A chain-drive system uses one or more roller chains to transmit power from

a differential to the rear axle. This system allowed for a great deal of vertical axle

movement (for example, over bumps), and was simpler to design and build than a rigid

driveshaft in a workable suspension. Also, it had less unsprung weight at the rear

wheels than the Hotchkiss drive, which would have had the weight of the driveshaft and

differential to carry as well. This meant that the vehicle would have a smoother ride. The

lighter unsprung mass would allow the suspension to react to bumps more effectively.

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Frazer Nash were strong proponents of this system using one chain per gear selected

by dog clutches. The Frazer Nash chain drive system, (designed for the GN Cyclecar

Company by Archibald Frazer-Nash and Henry Ronald Godfrey) was very effective,

allowing extremely fast gear selections. The Frazer Nash (or GN) transmission system

provided the basis for many "special" racing cars of the 1920s and 1930s, the most

famous being Basil Davenport's Spider which held the outright record at the Shelsley

Walsh Speed Hill Climb in the 1920s.

Parry-Thomas was killed during a land speed record attempt in his car 'Babs' when the

chain final-drive broke, decapitating him.

The last popular chain drive automobile was the Honda S600 of the 1960s.

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7.COIL SPRING

A coil spring, also known as a helical spring, is a mechanical device, which is typically

used to store energy due to resilience and subsequently release it, to absorb shock, or

30

A compression coil spring

A tension coil spring

A selection of conical coil springs

Oxy-cut spring showing deformation due to loss of tempering in adjacent turn

to maintain a force between contacting surfaces. They are made of an elastic material

formed into the shape of a helix which returns to its natural length when unloaded.

One type of coil spring is a torsion spring: the material of the spring acts in torsion when

the spring is compressed or extended. The quality of spring is judged from the energy it

can absorb. the spring which is capable of absorbing the greatest amount of energy for

the given stress is the best one. Metal coil springs are made by winding a wire around a

shaped former - a cylinder is used to form cylindrical coil springs.

7.1Variants

Types of coil spring are:

Tension/extension coil springs, designed to resist stretching. They usually have a

hook or eye form at each end for attachment.

Compression coil springs, designed to resist being compressed. A typical use for

compression coil springs is in carsuspension systems.Torsion springs, designed to resist twisting actions. Often associated to clothes pegs or up-and-over garage doors.

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8.DYNAMO

"Dynamo Electric Machine" (end view, partly section, U.S. Patent 284,110)

A dynamo is an electrical generator that produces direct current with the use of

acommutator. Dynamos were the first electrical generators capable of delivering power

for industry, and the foundation upon which many other later electric-power conversion

devices were based, including the electric motor, the alternating-currentalternator, and

the rotary converter. Today, the simpler alternator dominates large scale power

generation, for efficiency, reliability and cost reasons. A dynamo has the disadvantages

of a mechanical commutator. Also, converting alternating to direct current using power

rectification devices (vacuum tube or more recently solid state) is effective and usually

economic.

The word dynamo (from the Greek word dynamis; meaning power) was originally

another name for an electrical generator, and still has some regional usage as a

replacement for the word generator. A small electrical generator built into the hub of a

bicycle wheel to power lights is called a hub dynamo, although these are invariably AC

devices] and are actually magnetos.

8.1Description

The dynamo uses rotating coils of wire and magnetic fields to convert mechanical

rotation into a pulsing direct electriccurrent through Faraday's law of induction. A

dynamo machine consists of a stationary structure, called the stator, which provides a

constant magnetic field, and a set of rotating windings called the armature which turn

within that field. The motion of the wire within the magnetic field causes the field to push

on the electrons in the metal, creating an electric current in the wire. On small machines

the constant magnetic field may be provided by one or more permanent magnets; larger

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machines have the constant magnetic field provided by one or more electromagnets,

which are usually called field coils.

8.2Commutation

The commutator is needed to produce direct current. When a loop of wire rotates in a

magnetic field, the potential induced in it reverses with each half turn, generating an

alternating current. However, in the early days of electric experimentation,alternating

current generally had no known use. The few uses for electricity, such as electroplating,

used direct current provided by messy liquid batteries. Dynamos were invented as a

replacement for batteries. The commutator is essentially a rotary switch. It consists of a

set of contacts mounted on the machine's shaft, combined with graphite-block stationary

contacts, called "brushes", because the earliest such fixed contacts were metal

brushes. The commutator reverses the connection of the windings to the external circuit

when the potential reverses, so instead of alternating current, a pulsing direct current is

produced.

8.3Excitation

The earliest dynamos used permanent magnets to create the magnetic field. These

were referred to as "magneto-electric machines" or magnetos. However, researchers

found that stronger magnetic fields, and so more power, could be produced by

using electromagnets (field coils) on the stator. These were called "dynamo-electric

machines" or dynamos. The field coils of the stator were originally separately excited by

a separate, smaller, dynamo or magneto. An important development

by Wilde and Siemens was the discovery that a dynamo could also bootstrap itself to

be self-excited, using current generated by the dynamo itself. This allowed the growth of

a much more powerful field, thus far greater output power.

8.4Modern uses

Dynamos still have some uses in low power applications, particularly where low

voltage DC is required, since an alternatorwith a semiconductor rectifier can be

inefficient in these applications. Hand cranked dynamos are used in clockwork

radios,hand powered flashlights, mobile phone rechargers, and other human powered

equipment to recharge batteries.

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9.WELDING

Gas metal arc welding (MIG welding)

Welding is a fabrication or sculptural process that joins materials,

usually metals or thermoplastics, by causingcoalescence. This is often done

by melting the workpieces and adding a filler material to form a pool of molten material

(the weld pool) that cools to become a strong joint, with pressure sometimes used in

conjunction with heat, or by itself, to produce the weld. This is in contrast

with soldering and brazing, which involve melting a lower-melting-point material

between the workpieces to form a bond between them, without melting the work pieces.

There are several different ways to weld, such as: Shielded Metal Arc Welding, Gas

Tungsten Arc Welding, Tungsten Inert Gas and Metallic Inert Gas. MIG or Metallic Inert

Gas involves a wire fed "gun" that feeds wire at an adjustable speed and sprays a

shielding gas (generally pure Argon or a mix of Argon and CO2) over the weld puddle to

protect it from the outside world. TIG or Tungsten Inert Gas involves a much smaller

hand-held gun that has a tungsten rod inside of it. With most, you use a pedal to adjust

your amount of heat and hold a filler metal with your other hand and slowly feed it. Stick

welding or Shielded Metal Arc Welding has an electrode that has flux, the protectant for

the puddle, around it. The electrode holder holds the electrode as it slowly melts away.

Slag protects the weld puddle from the outside world. Flux-Core is almost identical to

stick welding except once again you have a wire feeding gun, the wire has a thin flux

coating around it that protects the weld puddle.

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Many different energy sources can be used for welding, including a gas flame,

an electric arc, a laser, an electron beam,friction, and ultrasound. While often an

industrial process, welding may be performed in many different environments, including

open air, under water and in outer space. Welding is a potentially hazardous

undertaking and precautions are required to avoid burns, electric shock, vision damage,

inhalation of poisonous gases and fumes, and exposure to intense ultraviolet radiation.

Until the end of the 19th century, the only welding process was forge welding,

which blacksmiths had used for centuries to join iron and steel by heating and

hammering. Arc welding and oxyfuel welding were among the first processes to develop

late in the century, and electric resistance welding followed soon after. Welding

technology advanced quickly during the early 20th century as World War I and World

War II drove the demand for reliable and inexpensive joining methods. Following the

wars, several modern welding techniques were developed, including manual methods

like shielded metal arc welding, now one of the most popular welding methods, as well

as semi-automatic and automatic processes such as gas metal arc welding, submerged

arc welding, flux-cored arc welding and electroslag welding. Developments continued

with the invention of laser beam welding, electron beam welding, electromagnetic pulse

welding and friction stir welding in the latter half of the century. Today, the science

continues to advance. Robot welding is commonplace in industrial settings, and

researchers continue to develop new welding methods and gain greater understanding

of weld quality.

9.1Processes

9.1.1Arc

These processes use a welding power supply to create and maintain an electric arc

between an electrode and the base material to melt metals at the welding point. They

can use either direct (DC) or alternating (AC) current, and consumable or non-

consumable electrodes. The welding region is sometimes protected by some type of

inert or semi-inert gas, known as a shielding gas, and filler material is sometimes used

as well.

9.1.2Power supplies

To supply the electrical power necessary for arc welding processes, a variety of

different power supplies can be used. The most common welding power supplies are

constant current power supplies and constant voltage power supplies. In arc welding,

35

the length of the arc is directly related to the voltage, and the amount of heat input is

related to the current. Constant current power supplies are most often used for manual

welding processes such as gas tungsten arc welding and shielded metal arc welding,

because they maintain a relatively constant current even as the voltage varies. This is

important because in manual welding, it can be difficult to hold the electrode perfectly

steady, and as a result, the arc length and thus voltage tend to fluctuate. Constant

voltage power supplies hold the voltage constant and vary the current, and as a result,

are most often used for automated welding processes such as gas metal arc welding,

flux cored arc welding, and submerged arc welding. In these processes, arc length is

kept constant, since any fluctuation in the distance between the wire and the base

material is quickly rectified by a large change in current. For example, if the wire and the

base material get too close, the current will rapidly increase, which in turn causes the

heat to increase and the tip of the wire to melt, returning it to its original separation

distance.

The type of current used also plays an important role in arc welding. Consumable

electrode processes such as shielded metal arc welding and gas metal arc welding

generally use direct current, but the electrode can be charged either positively or

negatively. In welding, the positively charged anode will have a greater heat

concentration, and as a result, changing the polarity of the electrode has an impact on

weld properties. If the electrode is positively charged, the base metal will be hotter,

increasing weld penetration and welding speed. Alternatively, a negatively charged

electrode results in more shallow welds. Nonconsumable electrode processes, such as

gas tungsten arc welding, can use either type of direct current, as well as alternating

current. However, with direct current, because the electrode only creates the arc and

does not provide filler material, a positively charged electrode causes shallow welds,

while a negatively charged electrode makes deeper welds. Alternating current rapidly

moves between these two, resulting in medium-penetration welds. One disadvantage of

AC, the fact that the arc must be re-ignited after every zero crossing, has been

addressed with the invention of special power units that produce a square wave pattern

instead of the normal sine wave, making rapid zero crossings possible and minimizing

the effects of the problem.

9.2Processes

One of the most common types of arc welding is shielded metal arc welding (SMAW) it

is also known as manual metal arc welding (MMA) or stick welding. Electric current is

used to strike an arc between the base material and consumable electrode rod, which is

36

made of filler material (typically steel) and is covered with a flux that protects the weld

area from oxidation and contamination by producing carbon dioxide (CO2) gas during

the welding process. The electrode core itself acts as filler material, making a separate

filler unnecessary.

Shielded metal arc welding

The process is versatile and can be performed with relatively inexpensive equipment,

making it well suited to shop jobs and field work. An operator can become reasonably

proficient with a modest amount of training and can achieve mastery with experience.

Weld times are rather slow, since the consumable electrodes must be frequently

replaced and because slag, the residue from the flux, must be chipped away after

welding. Furthermore, the process is generally limited to welding ferrous materials,

though special electrodes have made possible the welding of cast iron, nickel,

aluminum, copper, and other metals.

Diagram of arc and weld area, in shielded metal arc welding

1. Coating Flow

2. Rod

3. Shield Gas

4. Fusion

5. Base metal

6. Weld metal

7. Solidified Slag

Gas metal arc welding (GMAW), also known as metal inert gas or MIG welding, is a

semi-automatic or automatic process that uses a continuous wire feed as an electrode

and an inert or semi-inert gas mixture to protect the weld from contamination. Since the

electrode is continuous, welding speeds are greater for GMAW than for SMAW.

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A related process, flux-cored arc welding (FCAW), uses similar equipment but uses wire

consisting of a steel electrode surrounding a powder fill material. This cored wire is

more expensive than the standard solid wire and can generate fumes and/or slag, but it

permits even higher welding speed and greater metal penetration.

Gas tungsten arc welding (GTAW), or tungsten inert gas (TIG) welding, is a manual

welding process that uses a nonconsumable tungsten electrode, an inert or semi-inert

gas mixture, and a separate filler material.[9] Especially useful for welding thin materials,

this method is characterized by a stable arc and high quality welds, but it requires

significant operator skill and can only be accomplished at relatively low speeds.

GTAW can be used on nearly all weldable metals, though it is most often applied

to stainless steel and light metals. It is often used when quality welds are extremely

important, such as in bicycle, aircraft and naval applications. A related process, plasma

arc welding, also uses a tungsten electrode but uses plasma gas to make the arc. The

arc is more concentrated than the GTAW arc, making transverse control more critical

and thus generally restricting the technique to a mechanized process. Because of its

stable current, the method can be used on a wider range of material thicknesses than

can the GTAW process and it is much faster. It can be applied to all of the same

materials as GTAW except magnesium, and automated welding of stainless steel is one

important application of the process. A variation of the process is plasma cutting, an

efficient steel cutting process.

Submerged arc welding (SAW) is a high-productivity welding method in which the arc is

struck beneath a covering layer of flux. This increases arc quality, since contaminants in

the atmosphere are blocked by the flux. The slag that forms on the weld generally

comes off by itself, and combined with the use of a continuous wire feed, the weld

deposition rate is high. Working conditions are much improved over other arc welding

processes, since the flux hides the arc and almost no smoke is produced. The process

is commonly used in industry, especially for large products and in the manufacture of

welded pressure vessels. Other arc welding processes include atomic hydrogen

welding, electroslag welding, electrogas welding, and stud arc welding.

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10.TURNING

This article is about the machining operation. For the generic use of the word,

see rotating.

Roughing, or rough turning

Parting aluminium

Finish turning

Turning is a machining process in which a cutting tool, typically a non-rotary tool bit,

describes a helical toolpath by moving more or less linearly while the workpiecerotates.

The tool's axes of movement may be literally a straight line, or they may be along some

set of curves or angles, but they are essentially linear (in the nonmathematical sense).

Usually the term "turning" is reserved for the generation ofexternal surfaces by this

39

cutting action, whereas this same essential cutting action when applied

to internal surfaces (that is, holes, of one kind or another) is called "boring". Thus the

phrase "turning and boring" categorizes the larger family of (essentially similar)

processes. The cutting of faces on the workpiece (that is, surfaces perpendicular to its

rotating axis), whether with a turning or boring tool, is called "facing", and may be

lumped into either category as a subset.

Turning can be done manually, in a traditional form of lathe, which frequently requires

continuous supervision by the operator, or by using an automated lathe which does not.

Today the most common type of such automation is computer numerical control, better

known as CNC. (CNC is also commonly used with many other types of machining

besides turning.)

When turning, a piece of relatively rigid material (such as wood, metal, plastic, or stone)

is rotated and a cutting tool is traversed along 1, 2, or 3 axes of motion to produce

precise diameters and depths. Turning can be either on the outside of the cylinder or on

the inside (also known as boring) to produce tubular components to various geometries.

Although now quite rare, early lathes could even be used to produce complex geometric

figures, even the platonic solids; although since the advent of CNC it has become

unusual to use non-computerized toolpath control for this purpose.

The turning processes are typically carried out on a lathe, considered to be the oldest

machine tools, and can be of four different types such as straight turning,taper

turning, profiling or external grooving. Those types of turning processes can produce

various shapes of materials such as straight, conical, curved, or groovedworkpiece. In

general, turning uses simple single-point cutting tools. Each group of workpiece

materials has an optimum set of tools angles which have been developed through the

years.

The bits of waste metal from turning operations are known as chips (North America),

or swarf (Britain). In some areas they may be known as turnings.

10.1Turning operations

Turning specific operations include:

40

10.1.1Turning

Turning

This operation is one of the most basic machining processes. That is, the part is rotated

while a single point cutting tool is moved parallel to the axis of rotation. Turning can be

done on the external surface of the part as well as internally (boring). The starting

material is generally a workpiece generated by other processes such

as casting, forging, extrusion, or drawing.

10.1.1.1Tapered turning 

a) from the compound slide b) from taper turning attachment c) using a hydraulic

copy attachment d) using a C.N.C. lathe e) using a form tool f) by the offsetting of

the tailstock - this method more suited for shallow tapers.

10.1.1.2Spherical generation 

The proper expression for making or turning a shape is to generate as in to

generate a form around a fixed axis of revolution. a) using hydraulic copy

attachment b) C.N.C. (computerised numerically controlled) lathe c) using a form

tool (a rough and ready method) d) using bed jig (need drawing to explain).

10.1.1.3Hard turning 

Hard turning is a turning done on materials with a Rockwell C hardness greater

than 45. It is typically performed after the workpiece is heat treated.

The process is intended to replace or limit traditional grinding operations. Hard

turning, when applied for purely stock removal purposes, competes favorably

with rough grinding. However, when it is applied for finishing where form and

dimension are critical, grinding is superior. Grinding produces higher dimensional

accuracy of roundness and cylindricity. In addition, polished surface finishes of

Rz=0.3-0.8z cannot be achieved with hard turning alone. Hard turning is

appropriate for parts requiring roundness accuracy of 0.5-12 micrometres, and/or

surface roughness of Rz 0.8–7.0 micrometres. It is used for gears, injection

pump components, hydraulic components, among other applications.

41

11.DESIGN AND FABRICATION

First solid shaft is taken and turned in the lathe shop to reduce the diameter and length according to the components which are present.

The steel plates are taken and they are made as case by welding,the welding used in this work is “arc welding”.

The Rack is fitted on the top such that it mates with freewheel to rotate in positive direction.

The sprocket is fitted outside the casing. The sprocket is connected with the small sprocket which is attached with the dynamo.

12.WORKING

The working part of the “Dynamo street lamps”includes,

The Rack which is welded with the iron plate is also welded with the compression coil(helical)spring.The Rack is positioned in such a way to mate the freewheel that makes the freewheel to rotate in positive direction.The ball bearings are used for positioning the shaft .The casing are done between the bearings using wooden plates.The wooden plate are punched in centre using carpentary tools.The order of components in shafts are BALL BEARING1,FREE WHEEL1,FREE WHEEL2,FLY WHEEL,BALL BEARING2,LARGE SPROKET.The large sproket comes outside the casing.It is connected with the small sproket by the chaindrive.It is fitted in the speed brakers of the road.When a vehicle moves on the speed breakers,the rack is moved downwards and makes the freewheel to rotate in positive direction,again the rack comes to the original position using the spring action.Due to this the shaft continuously rotate.The large sproket is mated with the small sproket whivh tends the dynamo also to rotate to generate power.

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13.ADVANTAGES AND DISADVANTAGES

ADVANTAGES

DISADVANTAGES

14.SPECIFICATION AND CALCULATION

SPECIFICATION

CALCULATION

15.COST ANALYSIS

16.CONCLUSION

Thus the design and fabrication of the” Dynamo street lamps“ is done.

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