FIELD OF INVENTION
This invention relates to improved wheel of vehicle.
BACKGROUND/PRIOR ART
Currently available steel wheel of vehicle compns1ng of steel disc or wheel
center with a flange in the periphery welded to a rolled steel rim at its periphery
as shown in fig. 1, in which the wheel has its disc mounted on the well area
(fig. 2) of the rim welded to each other as indicated in fig. 3.
The assembly area of the rim and disc is more prone to failure due to high
stresses in welding. This failure in the welding area is due to the stress
generated by the torsional load produced (fig. 4) during dynamics of the vehicle.
Therefore, it is required to develop an improved wheel so as to reduce the above
mentioned torsional load acting on the welding.
OBJECTS OF THE INVENTION
The primary object of the present invention 1s to provide improved wheel of
vehicle which overcomes disadvantages associated with the prior art.
Another object of the present invention is to provide improved wheel of vehicle
which reduces the stress on welding thereby reducing the failure of wheel at
the area of w_elding.
Yet another object of the present invention is to provide improved wheel of
vehicle which results in remarkable improvement in the endurance life/ overall
life of the wheel.
SUMMARY OF THE INVENTION
The present invention is directed to an improved automobile wheel that
comprises a disc and a rim wherein said disc is welded in the rim inner profile.
The wheel is provided with the following:
I I
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• Its fitment area i.e. rim well inner periphery or the area where the disc is
to be fitted having groove I knurling.
• Its fitment area i.e. the disc outer periphery IS provided with
groove I knurling.
• The shape of the groove/knurling vanes as per the manufacturing
feasibility of the wheel.
• The pitch of the knurling/ groove varies according to the manufacturing
feasibility.
Alternatively, the wheel is provided with the following:-
• Localized flat/ embossing at the area joining the rim and the disc.
• The shape of the above said flat/ embossing may be of any formable
shape.
• The pitch of the flats/ embossing of any achievable value around the
profile.
• The depth of the embossing/flat can be extended to any possible values.
STATEMENT OF INVENTION
According to this invention, there is provided improved wheel of vehicle
comprising of a disc and a rim, wherein the disc is welded in the rim inner
profile, in which the rim well inner periphery /the disc outer periphery is
provided with groovejknurling.
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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:
Fig. 1 shows: wheel rim.
Fig. 2 shows: detailed view of the cross-section of the rim.
Fig. 3 shows: detailed view of wheel cross-section showing the weld area.
Fig. 4 shows: the torsional load direction and the direction of wheel rotation.
Fig. 5 shows: rim showing the groovejknurling.
Fig. 5Atypical flattening after the assembly process
Fig. 6 shows: view of disc showing groove I knurling.
Fig. 6A shows: possible design of the local embossing that can be adopted.
Fig. 7 shows: disc fitted in the secondary well of the rim.
DETAIL DESCRIPTION OF THE PRESENT INVENTION WITH REFERENCE
TO THE ACCOMPANYING DRAWINGS:
The present invention discloses improved wheel of vehicle. In the present
invention, the fitment area of the rim and disc is modified i.e. rim well inner
periphery (as shown in fig. 5) and the disc spoke outer periphery (as shown in
fig. 6).
Now, reference may be made to fig. 7, wherein the disc is fitted into the
secondary well area of the rim. The groovejknurling may be provided at either
of disc or rim. The knurling/ groove is provided at the inner periphery of the rim
and/ or at the outer periphery of the disc flange.
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It is more effective when the groovejknurling is provided on both the rim &
disc. The presence of these provides grip between the rim and disc and thereby
diminishing the torosional load acting at the welded area joining both rim and
disc.
The presence of the groovejknurling on the wheel leads to remarkable
improvement in the endurance life/ overall life of said wheel.
The performance results showed negligible difference when tested with various
shapes of groovejknurling. However, in order to prevent initiation of any
possible crack from the groove, any ~harp corners is not provided in its shape.
The pitch of the groove is provided in such a way, considering its
manufacturing feasibility at the same time its count is maximum.
In another embodiment, localized flat may be provided at the area of fitment
where the disc is fitted into the rim surface.
The rim as a whole is formed by Roll-forming operation. In this operation, the
raw material i.e., a rectangular piece of sheet with predetermined dimensions is
made to roll between different rollers with different cross section. This finally
gives the rim its circular shape.
The already formed disc is assembled into the roll formed rim where the two
fitting areas have interference fit, in addition to the welding that holds both the
parts together.
At this fitment area of the rim and disc with the provision of some localized flat
may add grip between the two and thereby reducing the load on the welding.
Even though there is 'interference fit' between the rim and disc, since both are
of circular shape, the torsional load directly affects the weld. On the other hand
if the circular shape is given small flats at its tangent and at multiple locations,
it constricts the torsional load in the circular direction to a certain extend
thereby reducing the load on the welding.
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However, this can be provided only after the assembly of the disc and rim as,
giving the flat individually on rim and disc is not feasible. The local flat can be
described as an embossing operation with any formable shape. This includes
tangential flattening along the well as in the fig. (fig: 5A) .Further to this some
possible options are shown in the figure: 6A.
The implementation of these local flat/ embossing on the wheel showed drastic
improvement in the endurance life/ overall life while testing. The performance
results showed negligible difference when tested with various shapes of
flat/ embossing. However, in order to prevent initiation of any possible crack
from the groove, its shape is not provided with any sharp corners. The pitch of
the groove is determined in a way, considering its manufacturing feasibility at
the same time its count is maximum.
Reference numerals
Fig. 1
Rim- 1
Disc- 2
Welding - 3
Fig. 2
Flange- 4
Hump -5
Well- 6
Bead seat width- 7
Fig. 3
Well- 6
Welding- 3
Rim- 1
Disc- 2
Fig. 4
Rim- 1
Disc- 2
Weld-- 3
Wheel rotation - 8
Torsional load at welding - 9
Fig. 5
Knurling/ Groove -12
Rim well inner periphery -R
Fig. 6
Knurling/Groove- 12
Disc spoke outer periphery -13
Fig. 7
Secondary drop well - 11
Primary drop well- 10
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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:-

WE CLAIM:
1. Improved wheel of vehicle comprising of a disc and a rim, wherein the
disc is welded in the rim inner profile, in which the rim well inner
periphery/the disc outer periphery is provided with groovefknurling.
2. Improved wheel of vehicle comprising of a disc and a rim, wherein the
disc is welded in the rim inner profile, in which localized flat/ embossing
is provided at the area joining the rim and disc.
3. Improved wheel of vehicle as claimed in claim 1, wherein the shape and
pitch of the groove/knurling varies according to the manufacturing
feasibility of the wheel.
4. Improved wheel of vehicle as claimed in claim 2, wherein the shape of the
flat/ embossing may be of any formable shape.
5. Improved wheel of vehicle as claimed in claim 1 or 3, wherein the
groovefknurling is provided on both the rim and disc.
6. Improved wheel of vehicle as claimed in any of the preceding claims,
leads to remarkable improvement in the endurance life/ overall life of said
wheel.
7. Improved wheel of vehicle substantially as herein described with
reference to the accompanying drawings.