FIELD OF THE INVENTION:
This invention is related to an air filter assembly, and more particularly to an efficient and
lightweight air filter assembly for automobiles.
BACKGROUND OF THE INVENTION
An Air filter assembly is essential for automobiles to provide dust-free/contamination-less air
supply to engine. Automobile engines such as internal combustion engine requires large
amount of air in order to convert fuel into mechanical energy. The air particle contaminated
with dust and other abrasive particles may reduce the efficiency of the engine as well as may
reduce its life by creating wear and tear. Air filter assembly helps in removing foreign
particles. abrasive material such as dust particles, insects, sand and other unwanted
substances which may obstruct or contaminate the air passing through engine area and into
the vehicle. The continuous and free flow of air is very important for the efficient
performance of the engine. These air filters are thus required to be cleaned or get replaced
after a proper duration of time in order to avoid air clogging. By equipping high performance
air filters to the automobiles or properly changing the dirt filled air filter timely one can
drastically increase the life as well as the performance of the engine.
The automobiles which are operated in rural areas, dusty roads and muddy fields due to high
air contamination and presence of dust. requires much more efficient air filters for the better
and high performance; and maintenance of engine. These automobiles are generally equipped
with heavy duty engines or diesel engines which require many gallons of air to burn just one
liter of fuel. Hence it becomes extremely important that the air must be free from the
pollutants and contaminants.
For this reason several high performance filter assemblies have been designed. These high
performance filter assemblies such as compression air filter are generally made up of metal
sheet and are very expensive. There are other air filters such as oil bath air filters having
casing of steel body and wire-mess, which are bulkier in weight. Oil bath filters often
produce fumes which may cause pollution. Wire mess air filter assemblies may also suffer
disadvantage of getting corroded and are difficult to clean. These oil filters are banned in
many places due to emission of large amount of the pollutants. Some other filter materials are
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also in use such as cellulose based, synthetic paper based and foam materials which are
costlier to replace and have low dust holding capacity.
Due to several complications and requirements of high performance air filter assembly it is an
imminent need of the industry to not only develop an efficient high performance air filter
assembly but also an economical and durable air filter assemblies which may drastically
increase the life of the engine of automobiles generally used in rural areas and can be
affordable easily. Further, generally in rural areas automobiles such as tractors are used by
farmers who may not able to spend much on advanced machinery. As a result a cost effective
solution with efficient dust holding capacity is required.
Therefore, it is an object of this invention to not only overcome the limitations of the prior art
as well to provide an efficient, light weight and economically viable air filter assembly for
automobiles.
OBJECT OF THE INVENTION
An object of the invention is to provide a highly efficient, light weight and easily affordable
air filter assembly for automobile.
Another object of the invention is to provide a corrosion free air filter assembly which may
be easily cleaned.
SUMMARY OF THE INVENTION
The present invention discloses a highly efficient air filter assembly for automobiles. The
filter assembly comprises of a filter element housed inside the housing. The housing of the
filter assembly is made up of superior quality light weight material such as plastic may be of
any type, preferably the plastic is polypropylene. Polypropylene is lighter in weight in
comparison to other conventional materials used for the air filter assembly. The filter
assembly is designed to use paper filter which is made up of high quality linen paper.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1: depicts the specification of the various pm1s of the Air filter assembly including the
air filter element.
Figure 2: depicts the horizontal outer view of the air filter assembly.
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"' Figure 3: depicts the vertical outer view of the air filter assembly.
Figure 4: depicts the red band indicator during the normal working of the air filter assembly.
Figure 5: depicts the red band indicator, indicating a red band which informs the user that the
air filter element of the air filter assembly needs to be replaced.
Figure 6: depicts the red band indicator in the housing, Fig 6a depicting the indicator in the
normal indication and Fig. 6b, depicts the indicator in choked condition.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an air filter assembly for automobiles. The air filter assembly
is highly efficient and lighter in weight due to plastic casing and light weight filter element.
The air filter assembly is designed in accordance with the heavy internal combustion engines,
such as tractors which are operated in very dusty and rough areas. Therefore these vehicles
require very efficient and durable air filters, which may purify the air which passes through
the engine to substantially reduce the pollution and to increase the life of the engine. The air
filter body is made up of light weight plastic which may be molded in accordance with the
engine requirement and easily installed. The air filter element is formed of an air permeable
material such as linen paper which is lighter in weight in comparison to the conventional
papers which are being used as a filter element.
The invention will now be described, by the way of example, with reference to the
accompanying drawings as illustrated.
The Filter assembly of the present invention comprises of:
(i) A housing element, fitted a dust vacuator valve and coupled with an indicator: and
(ii) Filter element.
The housing element is made of a light weight material. The light weight material may be
made up ofvery light weight material such as polypropylene plastic.
The housing element is fitted with a dust vacuator valve and is coupled with an indicator.
The housing element is coupled with an indicator, the indicator, provides through a band, an
indication as to when the filter needs to be changed. The indicator provides a visual
indication of the performance of the air filter. The indicator may be placed in a place. easily
visible to the user of the vehicle. The indicator may be placed along with the filter or in any
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) place visible to the user. For instance, the indicator may be place in the dashboard in certain
vehicles, such as a car or an auto. In case of tractors, the indicator may be placed along with
the vehicle. The indicator is present as a red band. A red band is a signal in a vacuum
indicator, indicating the condition of the filter. Thus when a red band appears in switched off
engine mode, it means that filters has choked. The vacuum indicator works on the basis of
pressure difference at upstream and downstream of the filter.
The housing Dust vacuator valve is fitted with the housing element. The Vacuator Valve
comprises of a dust cup, where pre-cleaned dust is collected. This dust cap runs under a slight
vacuum when the engine is running. The normal engine pulsing of the vacuum causes the
Vacuator valve to open and close. This action automatically expels any collected dust and
water. The dust evacuator is for flushing out the accumulated dust in the filter assembly. The
vacuum indicator works on the basis of pressure difference at upstream and downstream of
the filter.
The Filter element further consists of an air permeable paper, which may be made up of a
high quality linen paper. The filter element may be placed in any manner, preferably in a
corrugated manner. The Filter element may be thinner compared to conventional paper. The
grammage or paper density is 100 GSM to 200 GSM, preferably 126 GSM, with pore size 40
mm to 60 mm and preferably 50 mm. Dust holding capacity of linen paper in filter element is
1100 gm - 1500 gm preferably 1200 gm compared to 400 gm -600 gm of conventional
papers used in air filter systems. The Rated air tlow through filter is 2 - 3 meter cubes per
minute and preferably 2.5 meter cubes per minute.
The Novel design of air filter assembly of the present invention lowers clamping pressure
inside assembly. Pressure drop is 630 mm W.C. to 640 mm W.C. and preferably 635 mm
W.C. The Dust addition rate in the range of 700 mg/m3 to 71 Omg/m3
. Dust holding capacity
of current invention is observed 1 077 gms, which is drastically high in comparison to
conventional paper air filters/oil bath filters having dust holding capacity not more than
500gm.
The filter assembly of present invention may be easily installed in different types of the
engine of various vehicles such as 2 wheelers, 3 wheels, 4-wheelers, and heavy duty vehicles.
Apart from on road applications the filters can also be used in off road applications like earth
moving equipments. tractors. compressors. generators etc.
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RefetTing to Figure 1 depicts the specification of the various parts of the Air filter assembly
including the air filter element. The casing of the air filter assembly may be positioned or
installed inside the engine compartment of the vehicle. The casing of the air filter may be
positioned horizontally or vertically as in accordance with the placement of the engine such
that to minimize any kind of leakage and distributes the flow of air evenly across the surface
of the filter element. The casing of the air filter is made up of a light weight material, is
selected from a plastic material preferably polypropylene. The filter element is placed inside
the casing of the filter assembly. The filter element is selected from an air permeable material
such as linen paper which is placed/ fitted inside the casing. The paper filter element used in
the present invention in the range of very cost effective and thinner in comparison to
conventional paper used as filter media. High quality linen paper has density in the range of
100gsm to 200gsm, preferably 126 gsm. The pore size ofthe paper is in the range of 40mm to
60mm, preferably 50mm. The pore size of the paper is in the range of 40mm to 60mm,
preferably 50mm. multiple pleated layers of the linen paper is housed in the polypropylene
housing. The pleated layer of the linen paper traps dust and other abrasive material which
could damage the engine by producing wear and tear. The linen paper is pleated in such a
manner so that it captures maximum amount of dust, and increases its overall dust holding
capacity. The linen paper is well fitted inside the casing of the air filter assembly. In
comparison to regular paper filter which has about 400 to 600 gm of dust holding capacity,
the high quality linen paper is having dust holding capacity in the range of 1100 to 1500 gm,
preferably 1200gm.
The casing of the present invention may be easily installed in different types of the engine of
various vehicles such as 2 wheelers, 3 wheels, 4-wheelers, and heavy duty vehicles. The air
filter assembly of the present invention is designed to work efficiently for heavy duty
vehicles which are operated in very dusty and adverse conditions.
The air filter assembly is connected to the engine of the ·vehicle by a hose. The air filter
element purifies the air which passes through and provides clean air to the engine of the
vehicle. The air filter element is having dust holding capacity in the range of 600 to 1500 gm,
preferably 1200gm. The rated air tlow of the air filter assembly is in the range of 2m3 /min to
3m3 /min, preferably 2.5m3 /min. The novel design of the air filter assembly reduces the
clamping pressure inside the assembly. The maximum pressure drop reported is in the range
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of 630mm W.C. to 640 mm W.C., preferably 635 mm W.C. and the dust addition rate in the
range of 700 mg/m3 to 71 Omg/m3
. The air filter assembly further comprises of a dust
vacuator valve and a red band indicator. The red band indicator is a sensing device, which
indicates a red band when the replacement of the air filter element is needed. The filter
assembly provides excellent results more than 99.95% of efficiency can be achieved.
By the use of such a high efficiency paper air filter, the life of engine gets drastically
increased by 7 years to 1 0 years in comparison to oil bath and wire mess air filters. The filter
may be easily gets replaced. The replacement time may vary depending upon the usage,
generally it is preferred that after the usage of engine for about 17,000km to 19,000km,
preferably 18,000km the filter needs to get changed. In contrary regular air filter required to
be changed after 1 O,OOOkm run of the engine. Further, for the convenience of the users, a red
band indicator is coupled with the air filter which will indicate whether the air filter is
required to get replaced or not. The air filter assembly coupled with the red band indicator
facilitates the user with an efficient air filter assembly which has automatic performance
indicator. The red band indicator is a sensor device, which may indicate a red band, so that
user will get an indication about the replacement time of the filter element.
Referring to Figure 2, depicts the horizontal outer view of the air filter assembly. The casing
of the air filter assembly is made up of light weight and durable polypropylene material. It is
designed in such a manner that it is well capable of bearing excess heat and pressure formed
inside the engine chamber.
Referring to Figure 3, depicts the vertical outer view of the air filter assembly.
Referring to Figure 4, depicts the red band indicator during the normal working of the air
filter assembly.
Referring to Figure 5, depicts the red band indicator, indicating a red band which informs the
user that the air filter element of the air tilter assembly needs to be replaced.
Referring to Figure 6, depicts the red band indicator in the housing, Fig 6a depicting the
indicator in the normal indication and Fig. 6b, depicts the indicator in choked condition.
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EXAMPLE 1: Observing the Dust holding capacity of the air filter element:
The linen paper filter element is subjected to the test of dust holding capacity:
Sl.no Initial Actual Initial At Line Net Dust Dust Efficienc
weigh weigh pressur the pressur pressur feed retaine y%
t kg. t kg. e W.C. end e drop e drop m dgm.
mm of W.C. w.c. gm.
the mm. mm.
cycl
e
W.C.
mm.
0 2.834 2.834 80 80 30 50 ....... ......... . ..........
1 2.834 3.003 80 180 30 150 170 169 99.41
2 3.003 3.170 180 225 30 195 170 167 98.24
.")' 3.170 3.337 227 320 30 290 170 167 98.24
4 3.337 3.504 322 435 30 405 170 167 98.24
5 3.504 3.672 435 540 30 510 170 168 98.82
6 3.672 3.841 540 620 30 590 170 169 99.41
7 3.841 3.911 620 670 30 640 70 70 100.00
Total 1090 1077
It is reported that the dust holding capacity is observed 1 077 gms, which is drastically high in
comparison to conventional paper air filters/oil bath filters having dust holding capacity not
more than 500gm. The dust holding capacity has drastically improved by 50 - 70% m
comparison to convention air paper filter.
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V EXAMPLE 2: Comparison of the performance of the linen paper and ordinary paper
which is used as filter element:
S.No. PARAMETER Linen Filter Ordinary paper
Filter
1 RATED AIR FLOW 2.5 m'/min 4.1 m'/min
2 CLEAN PRESSURE DROP 24m bar 41mbar
,.., .) DUST HOLDING CAPACITY >600gm >180gm
4 EFFICIENCY >99.95% >99%
5 ESTIMATED SERVICE >18,000 >10,000
INTERVAL
The linen paper which is used as filter element of the present invention is having drastically
high dust holding capacity as compared to convention papers used as filter element. The dust
holding capacity has increased by more than 3 times. The efficiency of the linen paper is in
accordance with the requirement of the heavy duty vehicle which is ordinarily not fulfilled by
those conventional paper air filters. The overall performance of the linen paper filter element
is reported very high in comparison to that of conventional paper filters.
Example 3: Plastic Stablitv test
The air filter of the present invention is placed in a circulating air-Oven and the temperature
was slowly increased to 1 00°C. The temperature was maintanied for 2 hours during the test .
Then the filter was cooled to room temperature for 2 hours. The filter was tested for any
significant change in colour or general appearance of the housing. It was also tested whether
the filter had any crack formations in housing.
Observation: It was observed that there was no change in shape, color and appearance
noticed after completed of the test. The filter assembly was also subjected to hydraulic leak
test at 5kg/cm2 pressure and no leaks were observed, clearly demonstrating the stability of
the filter of the present invention.
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ADVANTAGES:
1. The air filter assembly of the present invention is very economical and in comparison to oil
bath filters and other conventional filters, lighter in weight. The air filter assembly is lighter
by about l/3rd weight of that of oil bath filters.
2. The Efficiency of the air filter assembly 1s drastically increased in companson to
conventional air filters; the efficiency of the air filter ofthe present invention is 99.95%.
3. It is compatible and designed for heavy duty internal combustion engines, for example
which are used in tractors.
4. The air filter assembly of the present invention is highly beneficial for the rural people,
where vehicles have to pass through highly dusty areas and generally they are not able to
afford highly priced advanced air filters.
5. In comparison to other conventional air filters, the dust holding capacity of the air filter of
the present invention is very high, due to its superior design and efficient filter media.
6. Designed to provide outstanding performance in dusty areas, the replacement period of
filter media/estimated service interval has substantially increased by 50% to 80%.
7. The air filter assembly of the present invention may be placed horizontally to minimize the
oil spillage.
8. In comparison to conventional paper filter media, the paper filter media of the present
invention is highly efficient and light weight.
9. Red band indicator may be incorporated with the atr filter assembly of the present
invention.
10. The life of the engine may be substantially increased by 7 to 10 years by incorporating the
air filter assembly of the present invention.
11. Overall manufacturing cost is less as compared to the oil bath air filters, and is less
complicated. The air filter assembly may be easily molded into the different shapes and
designs in accordance with the engine to minimize the leakage and to increase its efficiency.
12. In comparison to oil bath filter, no emission of pollutant takes place, and clean air is
passed through the engine which minimizes both internal and external emission of the
pollutants which makes it Eco-friendly air filter assembly.
13. The filter media is durable and having high dust holding capacity and inexpensive to be
get replaced.
14. The filter is inexpensive. and provides better benefit-cost advantage.
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~ It should be understood that the foregoing description is only illustrative of the invention.
Various alternatives and modifications can be devised by those skilled in the art without
departing from the invention. Accordingly, the present invention is intended to embrace all
such alternatives, modifications and variances which fall within the scope of the appended
claims.
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I Claim:
1. A Filter assembly comprising:
(iii) a housing element, fitted a dust vacuator valve and coupled with an indicator;
and
(iv) filter element.
2. The filter assembly as claimed in claim 1, made up of a light weight material,
preferably, a plastic material, most preferably polypropylene.
3. The filter assembly as claimed in claim 1, wherein, dust vacuator valve is fitted with
the housing element comprises of a dust cup, where pre-cleaned dust is collected and
works on the basis of pressure difference at upstream and downstream of the filter.
4. The filter assembly as claimed in claim 1, wherein, the indicator provides visual
indication of the performance of the filter.
5. The filter assembly as claimed in claim 1, wherein, the indicator may be placed along
with the filter or in any place visible to the user.
6. The filter assembly as claimed in claim I, wherein, the filter element consists of an air
permeable paper, preferably linen paper.
7. The paper as claimed in claim 6, having a density in the range of I OOgsm to 200gsm,
preferably 126 gsm, pore size in the range of 40mm to 60mm, preferably 50mm.
grammage or paper density in the range of 100 GSM to 200 GSM, prderably 126
GSM, with pore size 40 mm to 60 mm and preferably 50 mm.
8. The paper as claimed in claim 6, having a dust holding capacity of linen paper in the
range of 1100 gm - 1500 gm preferably 1200 gm compared to 400 gm -600 gm and
rated air flow in the range of 2 - 3 meter cubes per minute and preferably 2.5 meter
cubes per minute.
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V 9. The filter assembly as claimed in claim 1, wherein, pressure drop is 630 mm W.C. to
640 mm W.C. and preferably 635 mm W.C and dust addition rate in the range of 700
mg/m3 to 71 Omg/m3
10. The filter assembly as claimed in claim 1, when installed in 2 wheelers, 3 wheels, 4-
wheelers, and heavy duty vehicles, earth moving equipments, tractors, compressors,
and generators.