Design and Fabrication of Bicycle Driven by Shaft and Gear System
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Compliance Engineering Journal ISSN NO: 0898-3577 Design and Fabrication of Bicycle Driven by Shaft and Gear System 1R. Panchamoorthy,2 P. Balashanmugam,3 S. Muthukumar ,4 N. Sivakumar 1,3,4 Assistant Professors, 2Associate Professor(1234 Deputed) Mechanical Engineering, Annamalai University, Chidambaram, Tamilnadu, India. Abstract: A chainless 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 derailleur. Recently, due to advancements in internal gear technology, a small number of modern shaft-driven bicycles have been introduced. Shaft-driven bikes have a be where a conventional bike would have its chain ring. This meshes with another bevel gear mounted on the drive shaft. The Bevel gears are the most efficient way of turning drives 90 degrees as compared to worm gears or crossed helical gear. The shaft drive only needs periodic lubrication using a grease gun to keep the gears running quiet and smooth. This “chainless” drive system provides smooth, quite and efficient transfer of energy from the pedals to the rear wheel. It is attractive in look compare with chain driven bicycle. It replaces the traditional method. Keywords: chain drive, drive torque, bicycle, forming process, internal gear technology 1. Introduction Elimination of Chain Drive in bi-cycle uses two sets of spiral bevel gears and a shaft rod to smoothly transfer power from the cranks to rear wheel. The bevel gears are made of heat treated comely and paired with high quality sealed cartridge bearings coupled to a steel shaft rod – all sealed inside lightweight, durable aluminum alloy. Our shaft drive, now in its third generation, has been in production since 1991, and is already on tens of thousands of bikes all over the world. By integrating our shaft drive with Shimano's internal hubs, our bikes not only have a sleek, modern look, but they deliver an incredibly smooth ride, great performance and eliminate the number one complaint people have always had about their bikes the chains and derailleur. With our shaft drive bikes; there is no more grease; no more mess; no more cuts on fingers or tears in clothes; and no more chain and derailleur maintenance. Just pure, worry-free riding fun. An elimination of chain drive in bicycle is a bicycle that uses a drive shaft instead of a chain to transmit power from the pedals to the wheel. Chain drive in by-cycle has 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. The 90-degree change of the drive plane that occurs at the bottom bracket and again at the rear hub requires the use of bevel gears. Bevel gears are the most efficient way of turning drives 90 degrees as compared to 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. 2.Literature Review The first shaft drives for cycles appear to have been invented independently in 1890 in the United States and England. The Drive shafts are carriers of torque; they are subject to torsion and shear stress, which represents the difference between the input force and the load. They thus need to be strong enough to bear the stress, without imposing too great an additional inertia by virtue of the weight of the shaft. Most automobiles today use rigid driveshaft to deliver power from a transmission to the wheels. A pair of short driveshaft is commonly used to send power from a central differential, transmission, or transaxie to the wheels. Shaft drives were introduced over a century ago. The first shaft drives for cycles appear to have been invented independently in 1890 in the United States and England. A. Fearnhead, of London Volume 11, Issue 2, 2020 Page No: 333 Compliance Engineering Journal ISSN NO: 0898-3577 developed one in 1890 and received a patent in October 1891. His prototype shaft was enclosed within a tube running along the top of the chain stay. Later models were enclosed within the actual chain stay. The first shaft drives for cycles appear to have been invented independently in 1890 in the United States and Britain. A. Fearnhead, of North London developed one in 1890 and received a patent in October 1891. His prototype shaft was enclosed within a tube running along the top of the chain stay; later models were enclosed within the actual chain stay. The shaft drive was not well accepted in Britain, so in 1894 Fearnhead took it to the USA where Colonel Pope of the Columbia firm bought the exclusive American rights. Belatedly, the British makers took it up, with in particular plunging heavily on the deal. Curiously enough, the greatest of all the Victorian cycle engineers, Professor Archibald Sharp, was against shaft drive; in his classic 1896 book "Bicycles and Tricycles", he writes "The Fearnhead Gear.... if bevel-wheels could be accurately and cheaply cut by machinery, it is possible that gears of this description might supplant, to a great extent, the chain-drive gear; but the fact that the teeth of the bevel-wheels cannot be accurately milled is a serious obstacle to their practical success". In the USA, they had been made by the League Cycle Company as early as 1893. Soon after, the French company Metropole marketed their Acatane. By 1897 Columbia began aggressively to market the chainless bicycle it had acquired from the League Cycle Company. Chainless bicycles were moderately popular in 1898 and 1899, although sales were still much smaller than regular bicycles, primarily due to the high cost. The bikes were also somewhat less efficient than regular bicycles: there was roughly an 8 percent loss in the gearing, in part due to limited manufacturing technology at the time. The rear wheel was also more difficult to remove to change flats. Many of these deficiencies have been overcome in the past century. In 1902, The Hill-Climber Bicycle Mfg. Company sold a three-speed shaft-driven bicycle in which the shifting was implemented with three sets of bevel gears. While a small number of chainless bicycles were available, for the most part, shaft-driven bicycles disappeared from view for most of the 20th century. There is, however, still a niche market for chainless bikes, especially for commuters, and there is a number of manufacturers who offer them either as part of a larger range or as a primary specialization. A notable example is Biomega in Denmark. Shaft drives operate at a very consistent rate of efficiency and performance, without adjustments or maintenance, though lower than that of a properly adjusted and lubricated chain. Shaft drives are typically more complex to disassemble when repairing flat rear tyres, and the manufacturing cost is typically higher. A fundamental issue with bicycle shaft-drive systems is the requirement to transmit the torque of the rider through bevel gears with much smaller radii than typical bicycle sprockets. This requires both high quality gears and heavier frame construction. Since shaft-drives require gear hubs for shifting, they gain the benefit that gears can be shifted while the bicycle is at a complete stop or moving in reverse, but internal hub geared bicycles typically have a more restricted gear range than comparable derailleur-equipped bicycles. The Drive shafts are carriers of torque, they are subject to torsion and shear stress, which represents the difference between the input force and the load. They thus need to be strong enough to bear the stress, without imposing too great an additional inertia by virtue of the weight of the shaft. Most automobiles today use rigid driveshaft to deliver power from a transmission to the wheels. A pair of short driveshaft is commonly used to send power from a central differential, transmission, or transaxiel to the wheels. 3. Components and Description The Fabrication of Bicycle Driven by Shaft and Gear System consists of the following components (shown in figure 1). Pedal Fender Frame Hub Driven Shaft Bearing Volume 11, Issue 2, 2020 Page No: 334 Compliance Engineering Journal ISSN NO: 0898-3577 Bevel gear Fig 1. Components of bicycle 3.1. Pedal A bicycle pedal is the part of a bicycle that the rider pushes with their foot to propel the bicycle. It provides the connection between the cyclist's foot or shoe and the crank allowing the leg to turn the bottom bracket spindle and propel the bicycle's wheels. on which the foot rests or is attached, that is free to rotate on bearings with respect to the spindle. Part attached to crank that cyclist rotate to provide the bicycle power as shown in figure 2. Fig 2. Pedal 3.2. Fender Piece of curved metal covering a part of wheel (shown in figure 3) to protect the cyclist from being splashed. Fig 3. Fender Volume 11, Issue 2, 2020 Page No: 335 Compliance Engineering Journal ISSN NO: 0898-3577 3.3. Front Brake Mechanism activated by brake cable compressing a calliper of return springs. It forces a pair of brake pads against the sidewalls to stop the bicycle.