1. SEMINAR PPT
MECHANICS OF PNEUMATIC TIRES
G.RAHUL DRAVID (712820114704)
BACHELOR OF ENGINEERING
INMECHANICAL ENGINEERING
RVS COLLEGE OF ENGINEERING AND TECHNOLOGY, COIMBATORE-641 402
3. INTRODUCTION
• Tyre is a rubber member which gives the
cushion to the automobile. It consists of outer
cover i.e. tyre proper and tube inside.
• The tyre-tube assembly is mounted over the
wheel rim and air inside the tube carries
entire load and provides cushion.
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4. Functions of tyre
• To support the vehicle load.
• To provide cushion against the shocks.
• To transmit driving and braking forces to the
road.
• To provide cornering power for smooth steering.
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5. Properties of tyres
• Non-skidding
• Uniform wear
• Load-carrying
• Cushioning
• Power consumption
• Tyre noise
• Balancing
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7. Advantages of tubeless tyres
• Lesser unsprung weight.
• Better cooling.
• Lesser rolling resistance.
• Comfortable ride.
• Slower leakage of air.
• Simpler assembly.
• Improved safety.
8. NON PNEUMATIC TYRES
• Bridgestone Corporation announced it has developed
“Air Free Concept (Non-Pneumatic) Tire” at the 43
Tokyo Motor Show 2013.
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9. INTRODUCTION
• Since the earlier invention of a non-pneumatic wheel in
1920’s, the non-pneumatic tire (NPT) is getting more
attention due to its advantages over the pneumatic
counterpart.
• Many design studies are still needed from the viewpoint
of material, pattern, and structures.
• However, no systematic research for such important
design issues has been reported in the literature up to
now.
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10. The airless tire is not a new idea –
“MichelinTweel” is just another example - but
Bridgestone claims that this is the first design of its
kind that is ready for mass production.
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11. What makes tyres “AIR LESS”
• Structure of spokes stretching along the inner
sides of the tires supporting the weight of the
vehicle.
• A synthetic resin that becomes flexible when
heated, can be processed into a variety of shapes,
and becomes hard when cooled. The changes
from heating and cooling can generally be
repeated, making it easy to both mold and
recycle the material.Untitled.mp4
13. ADVANTAGES
• The tires require less maintenance
• The worry of punctures is eliminated.
• The materials used in the tires and the spoke
structure are 100% recyclable.
• Provides low rolling resistance and
contributing to reductions in co2 emissions.
• Nothing to do with fuel efficiency in a direct
way, only offering the benefit that it will never
influence consumption.
14. Increased versatility
• Using high-strength but flexible high-
performance resin as a material has
increased versatility through improved load-
bearing capabilities and driving performance.
• High-speed travel (maximum 60 km/h) in
ultralight vehicles has also become possible.
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15. Low rolling resistance
• About 90% of energy loss from tire rolling resistance
comes from repeated changes in the shape of tires as
they roll. Bridgestone has succeeded in making a
significant reduction in energy loss by using proprietary
materials technologies and simplifying the structure of
the tires.As a result, these “Air Free Concept tire” have
achieved the same level of low rolling resistance as
our pneumatic fuel-efficient tires, making possible a
contribution to reductions in CO2 emissions.
NOTE: 1. Still in the testing phase
2. There is no word on price or a release date for standard vehicle
versions.
18. When the Tweel is put to the road, the spokes absorb road
impacts the same way air pressure does in pneumatic tires. The
tread and shear bands deform temporarily as the spokes bend,
then quickly spring back into shape.
20. FUTURE CHALLENGES
• Goodyear in collaboration with
NASA Glenn Research Center
(GRC), develop non-pneumatic
tyres for use first on the moon,
and eventually on Mars.
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21. • “The basic rubber-pneumatic design used on
Earth does not have the same utility on the
moon,” said NASA Principal Investigator Vivake
Asnani.
• There are no lunar roads. Lunar tyres need to be
designed to develop traction on sandy undulated
terrain, in regions that humans have never even
seen up close.
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22. • The Spring Tire has now been
recognized with a so-called “Oscar of
Innovation” at the 44th Annual R&D 100
Awards in Orlando, Florida.
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