2. ABSTRACT:
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 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.
4. INTRODUCTION:
The first shaft drives for cycles appear to have
been invented independently in 1890 in the
United States and England.
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
5. SHAFT DRIVEN SYSTEM:
The shaft is connected between the pair of
spiral bevel gears.
The main application of the spiral bevel gear
is in a vehicle differential, where the direction
of drive from the drive shaft must be turned
90 degrees to drive the wheels.
The helical design produces less vibration
and noise than conventional straight-cut or
spur-cut gear with straight teeth.
7. Shaft Drive Versus Chain
High durability Low durability
Less noise Noisy
Safe no chain bite Tear and soil clothing
90%+ efficient and cut hands
(consistently with 75% - 95% efficient
minimal maintenance) (varies depending on
Easy - no grease or condition and upkeep)
external components to Dirty and greasy chain;
disturb or damage sharp sprocket teeth;
delicate components
susceptible to damage
