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FIELD OF INVENTION
This invention relates to novel telescopic crash box of vehicle for absorbing
impact energy.
PRIOR ART
A Crash Box is known to have been provided, which is equipped with crush
initiators for absorbing the kinetic energy induced during any crash. The
conventional crash box absorbs the impact energy by undergoing plastic
deformation. In case of low speed crash repairing cost for conventional crash
box is very high.
Some telescopic energy absorbers are also available. However, those are either
pneumatic or hydraulic. Most of these telescopic arrangements use a piston
cylinder arrangement for energy absorption. The manufacturing, maintenance
and repairing cost for such provisions are high. Also, most of the telescopic
energy absorbers are represented by circular cross sections, whereas for crash
energy absorption rectangle or other polygons are recommended for better
energy absorption.
Most of the telescopic energy absorbers are not equipped with crush initiators
which are a very important factor for efficient energy absorption. Crush
initiators are not provided in most of the telescopic energy absorber because
with crush initiators it is difficult to get the telescopic mechanism working.
Now, reference may be made to the following prior arts:-
KR 100837105B1:- This Patent uses a ball in groove to achieve telescopic
mechanism for crash box, wherein crush initiators are not provided. Here,
spring is connected at one end, other end of which is connected to front plate
which could lead to bending of spring in case of bumper corner impact. Again,
it involves complex assembly procedure.
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KR 1020110051594A:- It does not involve telescopic mechanism. Protrusion
rods are provided, but it does not crush rather results in stiffer structure.
Again, no resilient material is provided. Further, it involves complex assembly
process.
JP 2007320530:- It uses telescopic mechanism for extending the bumper
assembly rather than crash box with no crush initiators. Again, it is not
provided for telescopic mechanism of the crash box and involves complex
assembly procedure.
Hence, it is required to develop novel telescopic crash box for absorbing impact
energy so as to address the aforesaid drawbacks.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide novel telescopic crash
box of vehicle for absorbing impact energy which overcomes disadvantages
associated with the prior art.
Further object of the present invention is to provide novel telescopic crash box
of vehicle for absorbing impact energy which is efficient and reliable.
SUMMARY OF THE INVENTION
This invention discloses an novel telescopic crash box of vehicle for absorbing
impact energy comprising of an inner crash box telescopically provided inside
an outer crash box, wherein the outer box is connected to the inner box by
means of a resilient material such as spring with a guiding pin provided on the
outer box. The above said assembly is mounted on back plate.
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STATEMENT OF INVENTION
According to this invention there is provided an novel telescopic crash box for
absorbing impact energy comprising of an inner crash box telescopically
provided inside an outer crash box, wherein the outer box is connected to the
inner box by means of a resilient material.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from
the ensuing description when read in conjunction with the accompanying
drawings and wherein:
Figure 1 shows: telescopic crash box according to the present invention.
Figure 2 shows: undeformed telescopic crash box.
Figure 3 shows: deformed telescopic crash box.
Figure 4 shows: cut-view of undeformed telescopic crash box.
Figure 5 shows: cut-view of deformed telescopic crash box.
DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE
ACCOMPANYING DRAWINGS
The present invention is directed to an novel telescopic crash box of vehicle for
absorbing impact energy. Now, reference may be made to fig. 1.
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Said crash box comprising of an inner crash box (I) accommodated inside an
outer crash box (O). The inner crash box undergoes telescopic movement inside
the outer crash box. This is because said inner box is telescopically provided
inside the outer crash box.
The inner box is connected to the outer box i.e. the end of inner box is
connected to farther end of outer box by means of a resilient material such as
spring (S) although other suitable material (s) readily apparent to persons
skilled in the art may be used.
Thus, the invention is not restricted to the use of examples given and other
resilient materials used in the art are understood to be within the scope of the
invention.
The spring (S) is connected to the outer box with the help of a guiding pin (G).
Said provision of spring alongwith guiding pin is made for efficient energy
absorption.
The above said assembly is mounted on back plate (B) for support.
The inner box is smaller in size than the outer box so that the same can be
comfortably housed inside the outer box.
Further, cross section of the box can be any polygon preferably rectangular
without restricting scope of the invention to the same. Again, size of the inner
and outer crash box is according to the requirement of vehicle.
The inner crash box (1) and the outer crash box (O) can be manufactured by the
method of casting/forging.
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The material of box is such as steel.
However, other materials obvious to a person skilled in the art are understood
to be within the perview of the invention.
The inner and outer box is provided with crush initiators for better energy
absorption in case of high speed impact. The guiding pin is used for free sliding
of inner box in case of a low speed impact. A spring with optimized stiffness is
used for absorbing the low speed impact energy. The spring stiffness lies in the
range of 20 N/mm-40 N/mm, which is subjected to change according to the
requirements and design of vehicle.
Again, there is no requirement of any fluids or air for absorbing energy. The
telescopic mechanism works efficiently with crush initiators.
The telescopic crash box is provided to absorb low speed impact energy without
any permanent deformation. The impact energy is dissipated by compression of
spring for low speed impact. During high speed crash, initial impact energy is
absorbed by compression spring followed by plastic deformation of telescopic
crash box getting crushed simultaneously. This results in better energy
absorption as compared to the conventional crash box. Telescopic crash box
can be manufactured by the method of sheet metal such as blank forming,
bending, spot welding, Arc welding (guide pin to front member).
Further, reference may be made to fig. 2-5 reflecting deformed and undeformed
spring based telescopic crash box.
Advantageous Features
- Polygonal shape for efficient energy absorption.
- Cost effective in respect of manufacturing, maintenance and repairing
cost.
- Provision of crush initiators.
- Simple assembly procedure.
- Use of telescopic mechanism.
- Reliable and efficient in operation.
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It is to be noted that the present invention is susceptible to modifications,
adaptations and changes by those skilled in the art. Such variant embodiments
employing the concepts and features of this invention are intended to be within
the scope of the present invention, which is further set forth under the
following claims:-

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WE CLAIM;
1. An novel telescopic crash box of vehicle for absorbing impact energy
comprising of an inner crash box telescopically provided inside an outer
crash box, wherein the outer box is connected to the inner box by means
of a resilient material.
2. An novel telescopic crash box of vehicle as claimed in claim 1, wherein
the end of the inner box is connected to farther end of said outer box by
means of a resilient material with a guiding pin provided on the outer
box.
3. An novel telescopic crash box of vehicle as claimed in claim 1 or 2,
wherein the crash box assembly is mounted on back plate.
4. An novel telescopic crash box of vehicle as claimed in any of the
preceding clams, wherein the inner and outer box is provided with crash
initiators for better energy absorption in case of high speed impact.
5. An novel telescopic crash box of vehicle as claimed in any of the
preceding claims, wherein the resilient material is such as a spring with
optimized stiffness provided for absorbing low speed impact energy.
6. An novel telescopic crash box of vehicle as claimed in any of the
preceding claims, wherein the crash box is provided with a polygonal
preferably with a rectangular cross section for better energy absorption.
7. An novel telescopic crash box of vehicle as claimed in any of the
preceding claims, wherein the inner/outer crash box is manufactured by
forging/casting such as herein described.
8. An novel telescopic crash box of vehicle as claimed in any of the
preceding claims, wherein the material of box is such as steel.
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9. An novel telescopic crash box of vehicle as claimed in any of the
preceding claims is associated with the advantageous features such as
herein described.
10. An novel telescopic crash box of vehicle for absorbing impact energy
substantially as herein described with reference to the accompanying
drawings.
Dated this 5* day of August, Q 2013
(SOMA RANI MISHRA)
OFL.S.DAVAR85CO.,
APPLICANTS AGENT