Presented by: SUSHIL LAMBA (10406EN008)
UPPU HARISH (10406EN015)
Timeline of the Bicycle
1791•Toy-like machine which was simply a wooden beam on two wheels and propelled by the rider himself
1817•Hobby-Horse or Draisienne (after the German Baron von Drais) or Velocifere
1839•The first true bicycle “Velocipede” developed by a Scottish blacksmith named Kirkpatrik Macmillan
1863
•The first commercially successful bicycle “Velocipede” developed by Pierre Michaux also called as “BoneShaker”
1870•High wheeled bicycles or “Penny Farthing” developed by James Starley
1879•“The Safety Machine” which was chain driven was patented by Henry.J.Lawson, also known as “Bicyclette”
1889•The Rover Safety completes the development of the bicycle form.
Hobby Horse (1791)
A wooden beam on two wheels, one behind
the other
Rider sat on the beam and drove the
machine by pushing his feet alternately
against the ground, as if skating
One could not turn this machine except by
lifting and dragging front wheel
It was displayed for the first time in 1791 in a
Parisian park as “Plaything of the Rich”
Draisienne (1817)
The first notable improvement in the hobby
horse was introduced by Baron von Drais
when the front wheel was turned by a
handle
The steerable front wheel was an important
addition
A man on Draisienne could exceed thespeed of runners or even horse driven carts
The awkward posture of the rider brought
ridicule
Bumpy ride on solid wheels over rough roads
resulted in many cases of hernia
The Treadle and Crank (1830)
First true bicycle which could be ridden with
both feet entirely off the ground (out of mud)
Kirkpatrik Macmillan employed the power ofleg muscles to turn the rear wheel instead of
dragging
Mechanism involves two bars suspended
from front end of the frame, whose lowerends, known as treadles, carried pedals
which were driven alternately by feet.
The linkage through the connecting rod and
crank the push and pull to rotary motion of
the rear wheel
Bone-shaker (1863)
First commercially successful bicycle
Developed by Pierre Michaux
It had a pair of pedals connected to the
front wheel and was ridden in same manner
as the basic children’s tricycles of today
Its wooden wheels with iron tyres on cobbled
roads gave the rider a very rough ride and
hence, nicknamed as Bone-Shaker
However, some comfort was achieved by
having seat on the leaf spring
The Penny Farthing (1870)
For a bone shaker to move at speeds of
modern bicycles, one would have to pedal
at very high RPM which would not at all becomfortable
Hence, the main aim was to increase the
velocity ratio
A simple and obvious way to increase the
velocity ratio was to use a larger front wheel
However, with the increase in velocity ratio,
there was a decrease in mechanical
advantage
The Safety Machine (1879)
These were low machines in which the
rider sat between two wheels and
paddled a low crank which drove the
rear wheel through a chain
However, it was identified that the size of
the wheel no longer determined the
velocity ratio
The low and rearward centre of gravityremoved the tendency of the machine to
come a cropper and hence called as
safety
A video presentation
DESIGN OF BICYCLE
Bicycle
Frame Seat Wheels
Rim
Spokes
Tire
Brakes Gears
1. WHEEL
• In the early days of bicycle development, the wheels were made of wooden spokes as used
in carts. These wooden spokes were very bulky to support the compression load.
• The first breakthrough in the wheel design came with Penny-Farthings. The load was carried
by thin wire spokes from the top portion of the rim, rather than being supported by thick
columnar spokes on the lower portion of the rim.
• The earlier tensioned-wire spokes ran straight in to the centre of the wheel. These spokes
could take the vertical load at the hub but couldn’t transmit the torque at the hub to the
rim. A couple of rigid bars with their own tensioned spokes were added for the purpose.
• This problem was solved by placing the spokes tangent to the hub.
• When a torque was applied to the hub of such a wheel through its sprocket, the wire-spokes
were tensioned, driving the rim in the same direction. A series of triangles formed by spokes
and the hub ensured that all loads were resisted by just the tensioning of spokes.
Pneumatic Tyres
• The air-filled tyres of modern bicycles were
first introduced on the safety bicycles in
1888.
• The air is contained in a thin pressurized
inner tube which is protected by a thicker
outer tyre.
• It has two steel-wire beads which snap into
grooves in the wheel rim keeping the tyre
in place.
Fig.: Cross-section of a Rim
2. BEARINGS
• The typical design of a bicycle bearing consists of a row of balls rolling between an outer
cup and an inner cone.
• The balls, cone and the cup, all are made of hardened steel to resist wear and
deformation.
Fig: A section of the front hub bearing
3. CHAIN The modern bush-roller chain was designed in 1880. It has high efficiency,
low weight and long life.
4. Free Wheel
• A free wheel is a device which connects the sprocket of the driven wheel to its
hub.
• It engages the wheel to the sprocket
when the sprocket rotates in the
forward direction, but lets the wheel roll
forward freely when the sprocket runs in
the backward direction.
5. Brakes
• The earliest of the bicycle brakes
consisted of just a metal spoon which was
operated by a hand lever and was
pressed against the rim of the front wheel.
It was effective only on a solid rubber
tyre.
• Later on, stirrup brake was developed. It is
still used on many bicycles. Modern
bicycles use calliper brakes.
The stirrup brakes operate
on the underside of the rim.
The friction pressure is build
up using lever mechanisms
that transmits the motion of
hand operated brake lever
to the brake pads with a
large value of mechanical
advantage.
Calliper brakes operate against the
sides of the rim. The outer sleeve is
attached at A and the inner cable at
B
Calliper brakes are operated through a flexible
cable which is made up of an inner-wire running
through an outer sleeve. The tension and
compression act on the two halves of the calipers
closing the brake shoes against the rim.
6. Frame
• The classical diamond frame is
well triangulated and quite
efficient. It has been the standard
frame since last 100 years.
• The top member resists load by
bending. The bending is reduced in
the other arrangement, resulting in
much more efficient structures.
7. Derailleur Gears
A transmission system consisting of a
chain, multiple sprockets, and a
mechanism (derailleur) to shift the chain
from one sprocket to another (more
common than hub gears).
Move lever on handlebar, changes
tension in derailleur cable.
Change in tension moves derailleur to one
side or the other moving the chain from
one sprocket to another.
There are two pulleys: the guide pulley
and the tension pulley. Guide pulley
pushes chain from one sprocket to the
other. The tension pulley maintains tension
in the chain.
Chainless Bicycles
These have Shaft Drives
which use precisely cut gears
and shaft rod to smoothly
and efficiently transfer power
from the pedals to the rear
wheel
Runs quieter, shifts smoother
and last longer than bikes
with chains.
These will be less expensive
and less work to maintain
Also, called as Dynamic
Bicycles use the Sussex ShaftDrive System (SDS)
When the bicycle was invented, people never thought that
this “machine” will be closely related to culture and society.
Well, sometimes unexpected things can happen, like in this
case, considering that the appearance of the bicycle
influenced the entire world!
Helping the Environment
•Cycling is not only important to the health of the
people riding, but also those of the surrounding
environment
•The bicycle does not pollute any air or sound.
More bicycles, less cars, more green space. In
conclusion, a healthy environment for all of us.
Helping our health
•A lot of diseases, like obesity or cardiovascular
diseases are increasing. But, we all have a
sedentary lifestyle, because we find no time for
practicing sports.
•We can use the bicycle in our daily activities,
and in this way we can get the “sports benefits”.
Economical help
•We all need a device for our
mobility (in a faster way), but cars
are not “available” for all of us.
In this case, bicycles are the most
useful for us.
•Bicycles are more cheaper than
cars, and they don’t need any
taxes or fuels to be paid;
The involvement in culture
•The appearance of bicycles and their evolution, the innovations
according this device and the changements made by the first called
“The Walking Machine”, have led to the apparition of museums
and important exhibitions of bicycles in the entire world
• In sports, cycling and the competitions dedicated to it, are
bringing more and more tourists and lovers of bicycles
together, spreading the culture in terms of cycling, bikes,
athletes of this sports and the history of this machine,all
over the world.
EuroBike in France
Technical Museum-Bucharest
France Tour
http://www.jimlangley.net/ride/bicyclehistorywh.html
http://www.arvindguptatoys.com_arvindgupta_bicyclestory
english.pdf
http://www.google.com/images
http://www.exploratorium.edu/cycling
http://resource.www.pedalinghistory.com
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