4.2.1 OPERATION - Sri Sai Ram Institute of Tecnology



DESIGN AND IMPLENTATION OF REVERSE GEAR MECHANISM IN SHAFT DRIVEN TWO WHEELERSA PROJECT REPORTSubmitted by HARIPIRASTH D S (412411114017) PREM KUMAR G R (412411114037) ABISHEK A (412411114301)In partial fulfillment of the award of the degreeOfBACHELOR OF ENGINEERINGINMECHANICAL ENGINEERING236601074930SRI SAIRAM INSTITUTE OF TECHNOLOGY, CHENNAI-44ANNA UNIVERSITY: CHENNAI 600025 APRIL 2015 ANNA UNIVERSITY::CHENNAI 600 025BONAFIDE CERTIFICATECertified that this report “DESIGN AND IMPLEMENTATION OF REVERSE GEAR MECHANISM IN SHAFT DRIVEN TWO WHEELERS” is the bonafide work of “HARIPIRASATH D S (412411114017), PREM KUMAR G R (412411114037), ABISHEK A (412411114301)” who carried out under my supervision. SIGNATUREMr.A.SRITHAR,M.E., HEAD OF THE DEPARTMENTDepartment of Mechanical EngineeringSri Sai Ram Institute of TechnologyChennai – 600044SIGNATUREMr. M.MAREESWARAN, M.E., SUPERVISOR, ASST. PROFESSOR,Department of Mechanical EngineeringSri Sai Ram Institute of TechnologyChennai – 600044Submitted for the ANNA UNIVERSITY Examination held on____________ at SRI SAIRAM INSTITUTE OF TECHNOLOGY, Chennai- 44.INTERNAL EXAMINER EXTERNAL EXAMINERACKNOWLEDGEMENTWe express our deep sense of gratitude to our beloved Chairman Thiru.MJF.Ln.LEO MUTHU for the help and advice he has shared upon us.We express our gratitude to our CEO Mr.J.SAI PRAKASH LEO MUTHU and our Trustee Mrs.J.SHARMILA RAJAA for their constant encouragement in completing the project.We express our solemn thanks to our esteemed Principal Dr.K.PALANIKUMAR for having given us spontaneous and wholehearted encouragement for completing this project. We are indebted to our HOD Mr. A. SRITHAR for his support during the entire course of this project work.We express our gratitude and sincere thanks tour guide Mr.M.MAREESWARAN, Asst. Professor for his valuable suggestions and constant encouragement for successful completion of this project.Our sincere thanks to our project coordinator Mr.G.SHANMUGA SUNDAR, Asst. Professor for his kind support in bringing out this project successfully.Finally, we thank all the teaching and Non-teaching staff members of the Department of Mechanical Engineering and all others who contributed directly or indirectly for the successful completion of our project.ABSTRACT At present, the chain driven bikes have been a great trouble in aspects of maintenance, cleanliness, power transmission etc .So to overcome these effects we have replaced the chain driven bikes by shaft mechanisms and also have indulged a reverse mechanism in bikes as there is no system available to reverse the vehicle. At?times?when the front wheel gets into a trench it is very difficult to take the vehicle from parking. Even normal people face much problem to take the vehicle out of the parking?at that time. In order to take the vehicle out of the parking they need to seek others help or they should push it out of the parking. Also for handicapped people it is impossible to take reverse from the parking. As a help to them we have designed a gear position which will be fit to the vehicle without altering the existing gear. The paper deals with the design of such a gear position and the assembly process of the gear to the vehicle.TABLE OF CONTENTSCHAPTER NO.TITLEPAGE NO.ACKNOWLEDGEMENTABSTRACTLIST OF FIGURESiiiivviii 1. INTRODUCTION 1 1.1 HISTORY OF BICYCLES 1 1.2 REVERSE DRIVEN BICYCLE 2 1.3 CHAIN DRIVEN BIKES 3 1.3.1 HISTORY 4 1.4 SHAFT DRIVEN BIKES 5 1.5 REVERSE GEAR IN BIKE 9 2. LITERATURE SURVEY 11 2.1 DESIGN AND FABRICATION OF 11 SHAFT DRIVEN BICYCLE 2.2 DRIVE SHAFT MECHANISM IN 12 MOTOR VEHICLE 2.2.1 FABRICATION AND WORKING 12 2.3 DEVELOPMENT AND IMPLENTATION 13 OF REVERSE GEAR MECHANISM IN BIKE 2.4 ROADSTER CYCLE 14 CHAPTER NO.TITLEPAGE NO. 3 COMPONENTS 15 3.1 BEVEL GEAR 15 3.1.1 INTRODUCTION 16 3.1.2 TYPES 17 3.1.3 GEOMETRY OF BEVEL GEAR 19 3.1.4 ADVANTAGES 20 3.1.5 DISADVANTAGES 20 3.2 SHAFT DRIVE 20 3.3 DC MOTOR 22 3.3.1 ELECTRO MAGNETIC MOTOR 23 3.4 COTTER JOINT 25 3.4.1 TYPES OF COTTER JOINT 26 3.4.1.1 SOCKET AND SPIGOT JOINT 27 3.4.1.2 SLEEVE AND COTTER JOINT 27 3.4.1.3 GIB AND COTTER JOINT 28 3.4.2 APPLICATION OF COTTER JOINT 29 3.4.3 COMPARISON BETWEEN KEY AND 29 COTTER JOINTCHAPTER NO.TITLEPAGE NO. 4 OPERATION 30 4.1 LATHE 30 4.2 ARC WELDING 31 4.2.1 OPERATION 31 4.3 CYLINDRICAL GRINDING MACHINE 33 4.3.1 APPLICATIONS 34 4.4 BROACHING 35 4.4.1 PROCESS 36 4.4.2 USAGE 37 5 CONSTRUCTION AND WORKING 38 5.1 WORK METHODOLOGY 40 5.2 WORKING 40 5.2.1 REVERSE DIRECTION 40 5.2.2 FORWARD DIRECTION 41 5.3 DESIGN CALCULATION 41 6 CONCLUSION 45 7 REFERENCE 46 LIST OF FIGURESFIG NO.CAPTIONPAGE NO.1.1shaft driven bicycle21.2Chain Driven Two Wheeler41.3Shaft Drive Two Wheeler61.4Comet Gear Box102.1Shaft Drive Bicycle Components112.2Shaft Driven Bike Components122.3Roadster Cycle143.1Bevel Gear153.2Bevel Gear Terminology163.3Milter and Its Mating Gear173.4Spiral Gear183.5Double Helical Gear193.6Exposed drive shaft on BMW's R 32213.7DC Motor with Worm Gear223.8Cotter joint and its Components263.9Socket and Spigot Joint273.10Sleeve and Cotter Joint283.11Gib and Cotter Joint284.1Lathe304.2Arc Welding324.3Cylindrical Grinding Machine345.1Project in Top View in PRO-E Model38FIG NO.CAPTIONPAGE NO. 5.2Model in PRO-E395.3Project Fabrication395.4Lever when shifted right405.5Lever when shifted left41 CHAPTER 1INTRODUCTION1.1 HISTORY OF BICYCLE A?bicycle, often called a?bike?or?cycle, is a?human-powered,?pedal-driven,?single-track vehicle, having two?wheels?attached to a?frame, one behind the other. A bicycle rider is called a?cyclist, or bicyclist. Bicycles were introduced in the 19th century in Europe and, as of 2003, more than a billion have been produced worldwide, twice as many as the number of?automobiles?that have been produced.?They are the principal?means of transportation?in many regions. They also provide a popular form of recreation, and have been adapted for use as children's toys, general fitness, military and police applications, courier services, and bicycle racing. The basic shape and configuration of a typical?upright, or safety bicycle, has changed little since the first chain-driven model was developed around 1885.?But many details have been improved, especially since the advent of modern materials andcomputer-aided design. These have allowed for a proliferation of specialized designs for many types of cycling. The bicycle's invention has had an enormous effect on society, both in terms of culture and of advancing modern industrial methods. Several components that eventually played a key role in the development of the automobile were initially invented for use in the bicycle, including?ball bearings,?pneumatic tires, chain-driven?sprockets, and?tension-spoked wheels. The word?bicycle?first appeared in English print in?The Daily News?in 1868, to describe "Bysicles and trysicles" on the "Champs Elysées and Bois de Boulogne.”.?The word was first used in 1847 in a French publication to describe an unidentified two-wheeled vehicle, possibly a carriage.?The design of the bicycle was an advance on the?velocipede, although the words were used with some degree of overlap for a time. Other words for bicycle include "bike",?"pushbike",?"pedal cycle",?or "cycle".?In?Unicode, the?hexadecimal?code for "bicycle" is?1F6B2. The string?&?produces. REVERSE DRIVEN BICYLESFig 1.1 Shaft Driven Bicycle A?shaft-driven bicycle?is a?bicycle?that uses a?drive shaft?instead of a?chain?to transmit power from the pedals to the wheel. Shaft drives were introduced over a century ago, but were mostly supplanted by chain-driven bicycles due to the gear ranges possible with sprockets and?derailleurs. Recently, due to advancements in internal gear technology, a small number of modern shaft-driven bicycles has been introduced. Shaft-driven bikes have a large?bevel gear?where a conventional bike would have its?chain ring. This meshes with another bevel?gearmounted on the drive shaft. The use of bevel gears allows the axis of the drive torque from the pedals to be turned through 90 degrees. The drive shaft then has another bevel gear near the rear wheel hub which meshes with a bevel gear on the hub where the rear sprocket would be on a conventional bike, and canceling out the first drive torque change of axis. The 90-degree change of the drive plane that occurs at the?bottom bracket?and again at the?rear hub?uses bevel gears for the most efficient performance, though other mechanisms could be used, e.g.?hobson's joints,?worm gears?or?crossed helical gears. The drive shaft is often mated to a?hub gear?which is an internal gear system housed inside the rear hub. Manufacturers of internal hubs suitable for use with shaft drive systems include?NuVinci,?Rohloff,?Shimano,?SRAM, and?Sturmey-Archer.1.3 CHAIN DRIVEN BIKES 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.Fig 1.2 Chain Driven Two Wheeler1.3.1 HISTORY The oldest known application of a chain drive appears in the?Polybolos, a?repeating crossbow?described 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. Although the device did not transmit power continuously since the chains "did not transmit power from shaft to shaft, and hence they were not in the direct line of ancestry of the chain-drive proper",?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 and endless power-transmitting chain was depicted in the written?horological?treatise of the?Song Dynasty?(960–1279)?Chinese?engineerSu 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.1.4 SHAFT DRIVEN BIKES A?shaft-driven bicycle?is a?bicycle?that uses a?drive shaft?instead of a?chain?to transmit power from the pedals to the wheel. Shaft drives were introduced over a century ago, but were mostly supplanted by chain-driven bicycles due to the gear ranges possible with sprockets and?derailleurs. Recently, due to advancements in internal gear technology, a small number of modern shaft-driven bicycles has been introduced. Shaft-driven bikes have a large?bevel gear?where a conventional bike would have its?chain ring. This meshes with another bevel?gear mounted on the drive shaft. The use of bevel gears allows the axis of the drive torque from the pedals to be turned through 90 degrees. The drive shaft then has another bevel gear near the rear wheel hub which meshes with a bevel gear on the hub where the rear sprocket would be on a conventional bike, and canceling out the first drive torque change of axis.Fig 1.3 Shaft Drive Two Wheeler The 90-degree change of the drive plane that occurs at the?bottom bracket?and again at the?rear hub?uses bevel gears for the most efficient performance, though other mechanisms could be used, e.g.?hobson's joints,?worm gears?or?crossed helical gears. The drive shaft is often mated to a?hub gear?which is an internal gear system housed inside the rear hub. Manufacturers of internal hubs suitable for use with shaft drive systems include?NuVinci,?Rohloff,?Shimano,?SRAM, and?Sturmey-Archer. The oldest known application of a chain drive appears in the?Polybolos, a?repeating crossbow?described 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, and hence they were not in the direct line of ancestry of the chain-drive proper",?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 and endless power-transmitting chain was depicted in the written?horological?treatise of the?Song Dynasty?(960–1279)?Chinese?engineerSu 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. Roller chain and sprockets is a very efficient method of power transmission compared to (friction-drive)?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, urethane, 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 as it bends around the pulleys. Wear on rubber or plastic belts and their teeth is often easier to observe, and chains wear out faster than belts if not properly lubricated. One problem with Roller Chains is the variation in speed, or surging, caused by the acceleration and deceleration of the chain as it goes around the sprocket link by link. It starts as soon as the pitch line of the chain contacts the first tooth of the sprocket. This contact occurs at a point below the pitch circle of the sprocket. As the sprocket rotates, the chain is raised up to the pitch circle and is then dropped down again as sprocket rotation continues. Because of the fixed pitch length, the pitch line of the link cuts across the chord between two pitch points on the sprocket, remaining in this position relative to the sprocket until the link exits the sprocket. This rising and falling of the pitch line is what causes chordal effect or speed variation. In other words, 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 with?derailleurs?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. However, some newer synchronous belts have "equivalent capacity to roller chain drives in the same width".?In other words, a toothed belt as wide as a chain drive can transmit the same, or even slightly higher, amount of power. 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 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. 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.1.5 REVERSE GEAR IN BIKES To reverse the shaft driven bikes such as Ducati,Harley Davidson super bikes an gear box known as comet gear box is used that costs more than 20 thousand rupees in Indian rupee today.This comet gear box has an sun and gear planet arrangement in them where the drive shaft is connected to one side of sun gear and then the shafts from the gear are taken to the driven shaft.Thus this arrangement helps to engage the reverse process.Fig1.4 Comet Gear Box The Comet Gearbox is for go-karts, utility vehicles and other applications up to 16 hp. Lightweight, rugged gearbox that allows operator the selection of three positions: forward, neutral and reverse. Forward ratio is 1:1 and the reverse ratio is 2.7:1. Use this gearbox with a Comet torque converter system. Maximum input shaft speed of 4000 rpm. The unit has a 5 1/2" long 3/4" keyed shaft and the mounting pattern on the bottom is 1 3/4 x 3 15/16. It costs in a range of fifteen thousand to thirty thousand.CHAPTER 2LITERATURE SURVEY2.1 DESIGN AND FABRICATION OF SHAFT DRIVE FOR BICYCLE G. Hari Prasad, S.Marurthi, R.Ganapathi, M.Janardhan, M.P.Madhu sudhan.International Journal of Emerging Engineering Research and Technology Volume 2, Issue 2, May 2014. This project was developed for the users to rotate the back wheel of a two wheeler using propeller shaft. Usually in two wheelers, chain and sprocket method is used to drive the back wheel. But in this project, the Engine is connected at the front part of the vehicle. The shaft of the engine is connected with a long rod. The other side of the long rod is connected with a set of bevel gears. The bevel gears are used to rotate the shaft in 90 o angle. The back wheel of the vehicle is connected with the bevel gear (driven). Thus the back wheel is rotated in perpendicular to the engine shaft. Thus the two wheeler will move forward. According to the direction of motion of the engine, the wheel will be moved forward or reverse. This avoids the usage of chain and sprocket method. Fig 2.1 Shaft Drive Bicycle Components2.2 DRIVE SHAFT MECHANISM IN MOTOR VEHICLES. Vanangamudi, S. Prabhakar, C. Thamotharan and R. Anbazhagan.Middle-East Journal of Scientific Research, IDOSI Publications, 2014 The job involved is the design for suitable propeller shaft and replacement of chain drive smoothly to transmit power from the engine to the wheel without slip. It needs only a less maintenance because it will not get worn out during service as compared to chain drive. It is cost effective. Propeller shaft strength is more and also propeller shaft diameter is less. It absorbs the shock. Because the propeller shaft center is fitted with the universal joint is a flexible joint. It turns into any ANGULAR position. The both end of the shaft are fitted with the bevel pinion, the bevel pinion engaged with the crown and power is transmitted to the rear wheel through the propeller shaft and gear box.2.2.1 Fabrication and Working Principle: The engine is fixed to the frame stand. There are two bevel gears are used in this project. One bevel gear is coupled to the engine shaft and another one bevel gear is used to transfer the energy from engine shaft to the differential unit. The differential unit is fixed to the frame stand by the suitable arrangement. The differential unit one end is connected to the wheel by the suitable arrangement.Fig 2.2 Shaft Driven Bike Components2.3 DEVELOPMENT AND IMPLEMENTATION OF REVERSE DRIVE MECHANISM IN BIKESSathish kumar, J.Jerris, J.Purushothaman, J.Jude Shelley, A.Abdul khadeer, Ranjeet Pokharel, J.Arshad Basha, P.Saravanan.November 2014 in IJSR (INTERNATIONAL JOURNAL OF SCIENTIFIC RESEARCH) They have designed a gear box which will be fit to the vehicle without altering the existing gear box. The paper deals with the design of such a gear box and the assembly process of the gear box to the vehicle. The design deals with the conditions of the gear box operation, and the design of the gear box based on easy assembly and easy manufacturing at low cost. The reverse gear on the manual transmission system typically uses an Idler gear Idler gear is an intermediate gear which does not drive a shaft to perform any work. Sometimes, a single idler gear is used to reverse the direction, in which case it may be referred to as a reverse idler. In our system we are going to use the compound idler gear. The input gear is connected with the crank shaft and output gear is connected with the flywheel. During forward gear the input gear is directly meshed with the output gear. If the input gear rotates in clockwise direction, the output gear will rotate in anticlockwise direction. So the vehicle moves in the forward direction. During reverse gear the idler gear is meshed in between the input and output gear. Idler gear here using is a compound gear, so smaller gear in compound gear is meshed with input gear and larger gear is meshed with output gear. When the input gear rotates in clockwise direction the idler gear rotates in anticlockwise direction. Also the output gear meshed with idler gear rotates in clockwise direction. So the vehicle moves in reverse direction. The disadvantage is that sometimes the chain gets loosened easily and need to maintain frequently.2.4 ROADSTER CYCLE Kenneth S. Keyes Idosi publication in 2011An improved three-speed or coaster bicycle having a driver bevel gear connected to the pedals, a driven bevel gear at the hub of the rear wheel, one or more drive shafts having beveled gears at each end and capable of transmitting the rotation of the driver gear to the driven gear. This invention relates to coaster and three-speed bicycles, and in particular, to bicycles having bevel gears and one or more drive shafts that replace the traditional spur gears and chain.Fig 2.3 Roadster CycleCHAPTER 3COMPONENTS3.1 BEVEL GEAR Bevel gears?are?gears?where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped. Bevel gears are most often mounted on shafts that are 90 degrees apart, but can be designed to work at other angles as well.?The pitch surface of bevel gears is a?cone. Fig 3.1 Bevel GearFig3.2 Bevel Gear Terminology3.1.1 INTRODUCTION Two important concepts in gearing are?pitch surface?and?pitch angle. The pitch surface of a gear is the imaginary toothless surface that you would have by averaging out the peaks and valleys of the individual teeth. The pitch surface of an ordinary gear is the shape of a cylinder. The pitch angle of a gear is the angle between the face of the pitch surface and the axis. The most familiar kinds of bevel gears have pitch angles of less than 90 degrees and therefore are cone-shaped. This type of bevel gear is called?external?because the gear teeth point outward. The pitch surfaces of meshed external bevel gears are coaxial with the gear shafts; the apexes of the two surfaces are at the point of intersection of the shaft axes. Bevel gears that have pitch angles of greater than ninety degrees have teeth that point inward and are called?internal?bevel gears. Bevel gears that have pitch angles of exactly 90 degrees have teeth that point outward parallel with the axis and resemble the points on a crown. That's why this type of bevel gear is called a?crown?gear. Miter gears?are mating bevel gears with equal numbers of teeth and with axes at right angles. Skew bevel gears?are those for which the corresponding?crown gear?has teeth that are straight and?oblique.Fig3.3 Milter and Its Mating Gear3.1.2 TYPES Bevel gears are classified in different types according to geometry:Straight bevel gears?have conical pitch surface and teeth are straight and tapering towards apex.Spiral bevel gears?have curved teeth at an angle allowing tooth contact to be gradual and smooth.Fig 3.4 Spiral GearZerol bevel gears?are very similar to a bevel gear only exception is the teeth are curved: the ends of each tooth are coplanar with the axis, but the middle of each tooth is swept circumferentially around the gear. Zerol bevel gears can be thought of as spiral bevel gears (which also have curved teeth) but with a spiral angle of zero (so the ends of the teeth align with the axis).Hypoid bevel gears?are similar to spiral bevel but the pitch surfaces are?hyperbolic?and not conical.Fig 3.5 Double Helical Gear3.1.3 GEOMETRY OF THE BEVEL GEAR The cylindrical gear tooth profile corresponds to an involute, whereas the bevel gear tooth profile is an octoid. All traditional bevel gear generators (such as?Gleason, Klingelnberg, Heidenreich & Harbeck, WMW Modul) manufacture bevel gears with an octoidal tooth profile. IMPORTANT: For 5-axis milled bevel gear sets it is important to choose the same calculation / layout like the conventional manufacturing method. Simplified calculated bevel gears on the basis of an equivalent cylindrical gear in normal section with an involute tooth form show a deviant tooth form with reduced tooth strength by 10-28% without offset and 45% with offset [Diss. Hünecke, TU Dresden]. Furthermore those "involute bevel gear sets" causes more noise.3.1.4 ADVANTAGESThis?gear?makes it possible to change the operating angle.Differing of the number of teeth (effectively diameter) on each wheel allows?mechanical advantage?to be changed. By increasing or decreasing the ratio of teeth between the drive and driven wheels one may change the ratio of rotations between the two, meaning that the?rotational drive?and?torque?of the second wheel can be changed in relation to the first, with speed increasing and torque decreasing, or speed decreasing and torque increasing.3.1.5 DISADVANTAGESOne wheel of such gear is designed to work with its complementary wheel and no other.Must be precisely mounted.The shafts' bearings must be capable of supporting significant forces.3.2 SHAFT DRIVE A?drive shaft,?driveshaft,?driving shaft,?propeller shaft?(prop shaft), or?Cardan shaft?is a mechanical component for transmitting?torque?and rotation, usually used to connect other components of a?drive train?that cannot be connected directly because of distance or the need to allow for relative movement between them. As torque carriers, drive shafts are subject to?torsion?and?shear stress, equivalent to the difference between the input torque and the load. They must therefore be strong enough to bear the stress, whilst avoiding too much additional weight as that would in turn increase their?inertia. To allow for variations in the alignment and distance between the driving and driven components, drive shafts frequently incorporate one or more?universal joints,?jaw couplings, or?rag joints, and sometimes a?splined joint?or?prismatic joint.Fig3.6 Exposed drive shaft on BMW's R32 Drive shafts have been used on?motorcycles?since before WW1, such as the Belgian?FN motorcycle?from 1903 and the?Stuart TurnerStellar motorcycle of 1912. As an alternative to?chain?and?belt?drives, drive shafts offer relatively maintenance-free operation, long life and cleanliness. A disadvantage of shaft drive on a motorcycle is that?helical gearing,?spiral bevel gearing?or similar is needed to turn the power 90° from the shaft to the rear wheel, losing some power in the process. On the other hand, it is easier to protect the shaft linkages and drive gears from dust, sand, and mud. BMW?has produced shaft drive motorcycles since 1923; and?Moto Guzzi?have built shaft-drive?V-twins?since the 1960s. The British company,?Triumph?and the major Japanese brands,?Honda,?Suzuki,?Kawasaki?and?Yamaha, have produced shaft drive motorcycles. All geared models of the?Vespa?scooter produced to date have been shaft-drive.?Vespa's automatic models, however, use a belt.Motorcycle engines positioned such that the?crankshaft is longitudinal and parallel to the frame?are often used for shaft-driven motorcycles. This requires only one 90° turn in power transmission, rather than two. Bikes from Moto Guzzi and BMW, plus the?Triumph Rocket III?and?Honda ST series?all use this engine layout.Motorcycles with shaft drive are subject to?shaft effect?where the chassis climbs when power is applied. This effect, which is the opposite of that exhibited by chain-drive motorcycles, is counteracted with systems such as BMW's?Paralever, Moto Guzzi's?CARC?and Kawasaki's?Tetra Lever.3.3 DC MOTORFig 3.7 DC Motor with Worm Gear A?DC motor?is any of a class of electrical machines that converts direct current electrical power into mechanical power. The most common types rely on the forces produced by magnetic fields. Nearly all types of DC motors have some internal mechanism, either electromechanical or electronic; to periodically change the direction of current flow in part of the motor. Most types produce rotary motion; a linear motor directly produces force and motion in a straight line. DC motors were the first type widely used, since they could be powered from existing direct-current lighting power distribution systems. A DC motor's speed can be controlled over a wide range, using either a variable supply voltage or by changing the strength of current in its field windings. Small DC motors are used in tools, toys, and appliances. The?universal motor?can operate on direct current but is a lightweight motor used for portable power tools and appliances. Larger DC motors are used in propulsion of electric vehicles, elevator and hoists, or in drives for steel rolling mills. The advent of power electronics has made replacement of DC motors with AC motors possible in many applications. 3.3.1 ELECTRO MAGNETIC MOTORS A coil of wire with a current running through it generates an?electromagnetic?field aligned with the center of the coil. The direction and magnitude of the magnetic field produced by the coil can be changed with the direction and magnitude of the current flowing through it. A simple DC motor has a stationary set of magnets in the?stator?and an?armature?with one more windings of insulated wire wrapped around a soft iron core that concentrates the magnetic field. The windings usually have multiple turns around the core, and in large motors there can be several parallel current paths. The ends of the wire winding are connected to a?commutator. The commutator allows each armature coil to be energized in turn and connects the rotating coils with the external power supply through brushes. (Brushless DC motors have electronics that switch the DC current to each coil on and off and have no brushes.) The total amount of current sent to the coil, the coil's size and what it's wrapped around dictate the strength of the electromagnetic field created. The sequence of turning a particular coil on or off dictates what direction the effective electromagnetic fields are pointed. By turning on and off coils in sequence a rotating magnetic field can be created. These rotating magnetic fields interact with the magnetic fields of the magnets (permanent or electromagnets) in the stationary part of the motor (stator) to create a force on the armature which causes it to rotate. In some DC motor designs the stator fields use electromagnets to create their magnetic fields which allow greater control over the motor. At high power levels, DC motors are almost always cooled using forced air.Different number of stator and armature fields as well as how they are connected provide different inherent speed/torque regulation characteristics. The speed of a DC motor can be controlled by changing the voltage applied to the armature. The introduction of variable resistance in the armature circuit or field circuit allowed speed control. Modern DC motors are often controlled by?power electronics?systems which adjust the voltage by "chopping" the DC current into on and off cycles which have an effective lower voltage. Since the series-wound DC motor develops its highest torque at low speed, it is often used in traction applications such as?electric locomotives, and trams. The DC motor was the mainstay of electric?traction drives?on both electric and?diesel-electric locomotives, street-cars/trams and diesel electric drilling rigs for many years. The introduction of DC motors and an?electrical grid?system to run machinery starting in the 1870s started a new?second Industrial Revolution. DC motors can operate directly from rechargeable batteries, providing the motive power for the first electric vehicles and today's?hybrid cars?and?electric cars?as well as driving a host of?cordless?tools. Today DC motors are still found in applications as small as toys and disk drives, or in large sizes to operate steel rolling mills and paper machines. Large DC motors with separately excited fields were generally used with winder drives for?mine hoists, for high torque as well as smooth speed control using thyristor drives. These are now replaced with large AC motors with variable frequency drives. If external power is applied to a DC motor it acts as a DC generator, a?dynamo. This feature is used to slow down and recharge batteries on?hybrid car?and electric cars or to return electricity back to the electric grid used on a street car or electric powered train line when they slow down. This process is called?regenerative braking?on hybrid and electric cars. In diesel electric locomotives they also use their DC motors as generators to slow down but dissipate the energy in resistor stacks. Newer designs are adding large battery packs to recapture some of this energy.3.4 COTTER JOINT A cotter is a flat wedge shaped piece of rectangular cross section and its width is tapered (either on one side or on both sides) from one end to another for an easy adjustment. The taper varies from 1 in 48 to 1 in 24 and it may be increased up to 1 in 8, if a locking device is provided. The locking device may be taper pin or a set screw used on the lower end of the cotter. Fig 3.8 Cotter joint and its Components The cotter is usually made of mild steel or wrought iron. A cotter joint is temporary fastening and it is used to connect rigidly two co-axial rods or bars which are subjected to axial tensile or compressive forces. It is usually used in connecting a piston rod to crosshead of a reciprocating steam engine, a piston rod and its extension as a tail or pump road, strap end of connecting rod etc.3.4.1 TYPES OF COTTER JOINTFollowing are the three commonly used cotter joints to connect two rods by a cotter:Socket and spigot cotter joint,Sleeve and cotter joint,Gibb and cotter joint.3.4.1.1 SOCKET AND SPIGOT COTTER JOINT In a socket and spigot cotter joint, one end of the rods (say A) is provided with a socket type of end and the other end of the other rod(say B) is inserted into the socket. The end of the rod which goes into a socket is also called spigot. A rectangular hole is made in the socket and spigot. A cotter is then driven tightly through a hole in order to make the temporary connection between the two rods. The load is usually acting axially, but it changes its direction and hence the cotter joint must be designed to carry both the tensile and compressive loads. The compressive load is taken by the collar on the spigot.Fig 3.9 Socket and Spigot Joint3.4.1.2 SLEEVE AND COTTER JOINT Sometimes, a sleeve and cotter joint is used to connect two round rods or bars. In this type of joint, a sleeve or muff is used over the two rods and then two cotters (one on each rod) are inserted in the holes provided for them in the sleeve and rods.Fig 3.10 Sleeve and Cotter Joint The taper of the cotter is usually 1 in 24. It may be noted that the taper sides of the two cotters should face each other. The clearance is so adjusted that when the cotters are driven in, the two rods come closer to each other thus making the joint tight.3.4.1.3 GIB AND COTTER JOINTFig3.11 Gib and Cotter Joint A gib and cotter joint is usually used in strap end (or big end) of a connecting rod. In such cases, when the cotter alone (i.e. without gib) is driven, the friction between its ends and the inside of the slots in the strap tends to cause the sides of the strap to spring open (or spread) outwards. In order to prevent this, gibs are used which hold together at the ends of the stap. Moreover, gibs provide a larger bearing surface for the cotter to slide on, due to the increased holding power. Thus, provide a large bearing surface for the cotter to slide on, due to increased holding power. Moreover, gibs provide a larger bearing surface for the cotter to slide on, due to the increased holding power. Thus, the tendency of cotter to slacken back owing to friction is considerably decreased. The jib, also, enables parallel holes to be used.3.4.2 APPLICATIONS OF COTTER JOINT1. Connection of the piston rod with the cross heads2. Joining of tail rod with piston rod of a wet air pump3. Foundation bolt 4. Connecting two halves of fly wheel (cotter and dowel arrangement).3.4.3 COMPARISON BETWEEN KEY AND COTTER1. Key is usually driven parallel to the axis of the shaft which is subjected to torsion or twisting stress. Whereas cotter is normally driven at right angles to the axis of the connected part which is subjected to tensile or compressive stress along its axis.2. A key resists shear over a longitudinal section whereas a cotter resist shear over two transverse sections.CHAPTER 4OPERATIONS4.1 LATHEFig 4.1 Lathe? A?machine tool?which rotates the workpiece on its?axis?to perform various and a lot of operations such as?cutting,?sanding,?knurling,?drilling, facing, turning, order formation,? and a lot more with tools that are applied to the workpiece to create an object which has?symmetry?about an?axis of rotation. Lathes are used in?woodturning,?metalworking,?metal spinning,?thermal spraying, parts reclamation, and glass-working. Lathes can be used to shape pottery, the best-known design being the?potter's wheel. Most suitably equipped metalworking lathes can also be used to produce most?solids of revolution, plane surfaces and screw threads or?helices. Ornamental lathes can produce three-dimensional solids of incredible complexity. The work piece is usually held in place by either one or two?centers, at least one of which can typically be moved horizontally to accommodate varying work piece lengths. Other work-holding methods include clamping the work about the axis of rotation using a chuck or?collet, or to a?faceplate, using clamps or?dogs. Examples of objects that can be produced on a lathe include?candlestick?holders,?gun barrels,?cue sticks,?table?legs,?bowls,?baseball bats, musical instruments,?crankshafts, and?camshafts.4.2 ARC WELDING Gas metal arc welding?(GMAW), sometimes referred to by its subtypes?metal inert gas?(MIG)?welding?or?metal active gas?(MAG)?welding, is awelding?process in which an electric arc forms between a consumable?wire?electrode?and the workpiece metal(s), which heats the workpiece metal(s), causing them to melt, and join. Along with the wire electrode, a?shielding gas?feeds through the welding gun, which shields the process from contaminants in the air. The process can be semi-automatic or automatic. A constant?voltage,?direct current?power source is most commonly used with GMAW, but constant?current?systems, as well as?alternating current, can be used.There are four primary methods of metal transfer in GMAW, called globular, short-circuiting, spray, and pulsed-spray, each of which has distinct properties and corresponding advantages and limitations. Originally developed for welding?aluminum?and other non-ferrous materials in the 1940s, GMAW was soon applied to?steels?because it provided faster welding time compared to other welding processes. The cost of inert gas limited its use in steels until several years later, when the use of semi-inert gases such as?carbon dioxide?became common. Further developments during the 1950s and 1960s gave the process more versatility and as a result, it became a highly used industrial process. Today, GMAW is the most common industrial welding process, preferred for its versatility, speed and the relative ease of adapting the process to robotic automation. Fig 4.2 Arc WeldingUnlike welding processes that do not employ a shielding gas, such as?shielded metal arc welding, it is rarely used outdoors or in other areas of air volatility. A related process,?flux cored arc welding, often does not use a shielding gas, but instead employs an electrode wire that is hollow and filled with?flux. For most of its applications gas metal arc welding is a fairly simple welding process to learn requiring no more than a week or two to master basic welding technique. Even when welding is performed by well-trained operators weld quality can fluctuate since it depends on a number of external factors. All GMAW is dangerous, though perhaps less so than some other welding methods, such as?shielded metal arc welding. 4.2.1 OPERATION The basic technique for GMAW is quite simple, since the electrode is fed automatically through the torch (head of tip). By contrast, in?gas tungsten arc welding, the welder must handle a welding torch in one hand and a separate filler wire in the other, and in shielded metal arc welding, the operator must frequently chip off slag and change welding electrodes. GMAW requires only that the operator guide the welding gun with proper position and orientation along the area being welded. Keeping a consistent contact tip-to-work distance (the?stick out?distance) is important, because a long stick out distance can cause the electrode to overheat and also wastes shielding gas. Stick out distance varies for different GMAW weld processes and applications.?The orientation of the gun is also important—it should be held so as to bisect the angle between the workpieces; that is, at 45 degrees for a fillet weld and 90 degrees for welding a flat surface. The travel angle, or lead angle, is the angle of the torch with respect to the direction of travel, and it should generally remain approximately vertical. However, the desirable angle changes somewhat depending on the type of shielding gas used—with pure inert gases; the bottom of the torch is often slightly in front of the upper section, while the opposite is true when the welding atmosphere is carbon dioxide. 4.3 CYLINDRICAL GRINDING MACHINE The?cylindrical grinder?is a type of?grinding machine?used to shape the outside of an object. The cylindrical grinder can work on a variety of shapes; however the object must have a central axis of rotation. This includes but is not limited to such shapes as a?cylinder, an?ellipse, a?cam, or a?crankshaft. Fig 4.3 Cylindrical Grinding MachineCylindrical grinding is defined as having four essential actions:The work (object) must be constantly rotatingThe grinding wheel must be constantly rotatingThe grinding wheel is fed towards and away from the workEither the work or the grinding wheel is traversed with respect to the other.4.3.1 APPLICATION The cylindrical grinder is responsible for a plethora of innovations and inventions in the progression of science and technology. Any situation in which extremely precise metalworking is required, the cylindrical grinder is able to provide a level of precision unlike any other machine tool. From the automotive industry to military applications, the benefits the cylindrical grinder has given us are immeasurable.4.4 BROACHING Broaching?is a?machining?process that uses a toothed tool, called a?broach, to remove material. There are two main types of broaching:?linear?androtary. In linear broaching, which is the more common process, the broach is run linearly against a surface of the workpiece to effect the cut. Linear broaches are used in a?broaching machine, which is also sometimes shortened to?broach. In rotary broaching, the broach is rotated and pressed into the workpiece to cut an axis symmetric shape. A rotary broach is used in a?lathe?or?screw machine. In both processes the cut is performed in one pass of the broach, which makes it very efficient. Broaching is used when precision machining is required, especially for odd shapes. Commonly machined surfaces include circular and non-circular holes,?splines,?keyways, and flat surfaces. Typical workpieces include small to medium-sized?castings,?forgings, screw machine parts, and?stampings. Even though broaches can be expensive, broaching is usually favored over other processes when used for high-quantity production runs. Broaches are shaped similar to a saw, except the height of the teeth increases over the length of the tool. Moreover, the broach contains three distinct sections: one for roughing, another for semi-finishing, and the final one for finishing. Broaching is an unusual machining process because it has the?feed?built into the tool. The profile of the machined surface is always the inverse of the profile of the broach. The rise per tooth (RPT), also known as the?step?or feed per tooth, determines the amount of material removed and the size of the chip. The broach can be moved relative to the workpiece or vice versa. Because all of the features are built into the broach no complex motion or skilled labor is required to use it.?A broach is effectively a collection of?single-point cutting tools?arrayed in sequence, cutting one after the other; its cut is analogous to multiple passes of a?shaper.4.4.1 PROCESS The process depends on the type of broaching being performed. Surface broaching is very simple as either the workpiece is moved against a stationary surface broach, or the workpiece is held stationary while the broach is moved against it. Internal broaching is more involved. The process begins by clamping the workpiece into a special holding?fixture, called a?workholder, which mounts in the broaching machine. The broaching machine?elevator, which is the part of the machine that moves the broach above the workholder, then lowers the broach through the workpiece. Once through, the broaching machine'spuller, essentially a hook, grabs the?pilot?of the broach. The elevator then releases the top of the pilot and the puller pulls the broach through the workpiece completely. The workpiece is then removed from the machine and the broach is raised back up to reengage with the elevator.?The broach usually only moves linearly, but sometimes it is also rotated to create a spiral spline or gun-barrel?rifling. Cutting fluids?are used for three reasons;to cool the work piece and broachto lubricate cutting surfacesto flush the chips from the teeth. Fortified petroleum cutting fluids are the most common, however heavy duty water soluble cutting fluids are being used because of their superior cooling, cleanliness, and non-flammability. 4.4.2 USAGE Broaching was developed for machining internal keyways. However, it was soon discovered that broaching is very useful for machining other surfaces and shapes for high volume work pieces. Because each broach is specialized to cut just one shape either the broach must be specially designed for the geometry of the work piece or the work piece must be designed around standard broach geometry. A customized broach is usually only viable with high volume work pieces, because the broach can cost Rs.75,000 to Rs.150,000 to produce. Broaching speeds vary from 20 to 120?surface feet per minute?(SFPM). This results in a complete cycle time of 5 to 30?seconds. Most of the time is consumed by the return stroke, broach handling, and work piece loading and unloading. The only limitations on broaching are that there are no obstructions over the length of the surface to be machined, the geometry to be cut does not have curves in multiple planes,?and that the work piece is strong enough to withstand the forces involved. Specifically for internal broaching a hole must first exist in the work piece so the broach can enter. Broaching works best on softer materials, such as?brass,?bronze,?copper alloys,?aluminium,?graphite, hard?rubbers,?wood,?composites, and?plastic. However, it still has a good?machinability?rating on?mild steels?and?free machining steels. Broaching is more difficult on harder materials,?stainless steel and?titanium, but is still possible.CHAPTER 5CONSTRUCTION AND WORKING5.1 WORK METHODOLGY A steel frame is used for holding purpose. Five Bevel gears are used having 23 teeth each and hence their ratio as 1:1. A 12V DC motor having 80 rpm is connected with a bevel gear 1 using shaft. Bevel gear 2 is engaged with the bevel gear 1. On the other side, a two wheeler’s rear wheel is taken along with its bush and hub assembled. A cotter joint is fixed in wheel hub using shaft which is itself connected to two bevel gears 3 and 4 opposite to each other which is connected. .Fig 5.1 Project in Top View in PRO-E Model Another bevel gear 5 is adjacently placed with two oppositely placed bevel gears 3 and 4 as shown in the figure. Bevel gear 2 and 5 are connected using shaft. A lever is placed in between two bevel gears 3 and 4 which are in oppositely faced in order for engage and disengage purpose. These things are joined with the help of arc welding. A lead acid battery of 7.5 amps is connected to the motor using wires and switches for running purpose.Fig 5.2 Model In PRO-EFig 5.3 Project Fabrication5.2 WORKING When switch is ON then the motor starts running so bevel gears 1, 2, 5 also simultaneously running. 5.2.1 REVERSE DIRECTION Fig 5.4 Lever when shifted right When the lever is moved to the right direction then bevel gear 5 and 3 are engaged and bevel gear 5 and 4 are disengaged. As bevel gear 5 is rotating in anti-clockwise direction, gear 3 rotates in clockwise direction as shown in the figure and thus the rear wheel move in reverse direction. Thus for a rider if he wants to move in reverse direction he should move the lever into right direction.5.2.2 FORWARD DIRECTION When the lever is moved to the left direction then bevel gear 5 and 4 are engaged and bevel gear 5 and 3 are disengaged. Fig 5.5 Lever when shifted leftAs bevel gear 5 is rotating in anti clockwise direction, gear 4 also rotates in anti clockwise direction as shown in the figure and thus rear wheel move in forward direction.5.3 DESIGN CALCULATIONSSpeed = 80 rpmShaft diameter = 15mmGear inner diameter = 50 mmOuter diameter =80mmNo. of teeth= 23Breadth = 18mmPower = 0.25 hp motor =186.5wattsDiameter of pinion = 80 mmDesign of the shaftTorque acting on the pinion T= p*60/ (2πNp) N-m = 186.5*60/ (2*3.14*80) = 22.26 N-mSlant height of the pitch cone L = √((DG/ 2)2 + (Dp/ 2)2) = √(2(80/2)2) =56.57 mmMean radius Rm = (L- b/2)(Dp/ 2L) = (56.57-18/2)(80/(2*56.57)) = 33.636 mm Tangential force acting at the mean radius of the pinion is WT = T/ Rm = 22.26/ 33.636 * 103 = 661.91 NThe axial force acting on the pinion is WRH = WT tan? * sinθp1 = 661.91 * tan 14.5 * sin 45 = 121.04 NThe radial force acting on the pinion is WRV = WT * tan? * cosθp1 = 661.91 * tan 14.5 * sin 45 = 121.04 NThe bending moment due to WRH and WRV is given by M1 = WRV – WRH * RM = 121.04 – 121.04 * 33.636 = 3950.38 N mmThe bending moment due to tangential force WT is given by M2 = WT = 121.04 N mmResultant bending moment is M = √((M1)2 + (M2)2) = √ ((3950.38)2 + (121.04)2 ) = 3952.23 N mmEquivalent twisting moment is Te = √ (M2 + T2) = √ ((3952.23)2 + (22.26 * 103)2) = 22608.13 N mm But diameter of pinion dp = 15 mmShear stress of the pinion is given by τ = ( Te * 16) / ( π * 153) = 34.16 N/ mm2 2.Maximum load applied in cotter jointDiameter of the shaft d = 15 mmTensile stress σt = 50 N / mm2Maximum load applied will be P = π / 4 * d2 * σt = 3.14 / 4 * 152 *50 = 8835.72 N3. Increase in weightPercentage in increase in weight will be % W = (actual weight – original weight) / actual weight * 100 = (10 – 9.7) / 10 *100 = 3 % CHAPTER 6CONCLUSION The importance of engaging a reverse gear mechanism would help to reduce human effort and be a boon to the upcoming future engineering society. The replacement of the COMET GEAR BOX by the innovative bevel gear position in the shaft driven bikes has saved more than FIFTEEN THOUSAND in case of Indian money today for engaging reverse gear mechanism. This reverse mechanism in shaft driven bikes are very useful to handicapped people in terms of short legs, low powered people and mostly for women who are craze towards the bike. Thus using reverse gear mechanism in future there wouldn’t be problem for people to have a back drive in situations of: 1. Public parking 2. Struck in trench 3. Mashed up in heavy traffic 4. Reduce human burden by reducing totally human power usage. The increase in weight is also minimum so there won’t be any static balance problem. In future, this method can be brought to normal usage so that normal people and physically challenged people will have ease of work while reversing.CHAPTER 7REFERENCE1. Automobile Engineering, R.B. Gupta, 4 editions, 2006.2. Over Drive magazine, December edition, 2004.3. 4. 5. Gopalkrishnan, K., J. Sundeep Aanad and R. Udayakumar, 2013. Structural Properties Doped azopolyester and its characteristics, Middle-East Journal of Scientific Research, ISSN:1990-9233, 15(12): 1773-1778.6. Gopalakrishnan, K., M. Prem Jeya Kumar, J. Sundeep Aanand and R. Udayakumar, 2013. Thermal Properties of Doped Azopolyester and its Application, Indian Journal of Science and Technology, ISSN: 0974-6846, 6(6): 4722-4725. ................
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