Title of Invention

AN APPARATUS FOR CLEANING AIR USED BY AN ENGINE OF RAILWAY LOCOMOTIVES

Abstract Method & apparatus for an improved air filter system for railway locomotive in its first configuration comprising of, 1. pre – cleaner comprising : a. baffles, b. inlet support/mesh, 2. intermediate filter foam pack comprising : c. outlet support/mesh d. housing and 3. secondary fine filter. The invention in its second configuration comprising of – 1. pre cleaner – cyclonic pre cleaner, 2. secondary filter comprising a. intermediate foam pack, secondary bag/cassette type fine filter. The pre filter and fine filter being made of FPCP (Flexible Porous Cellular Plastic ) material.
Full Text FORM 2 THE PATENT ACT 1970
&
The Patents Rules, 2003
PROVISIONAL / COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
"METHOD & APPARATUS FOR AN IMPROVED AIR FILTER SYSTEM FOR RAILWAY
LOCOMOTIVES"

2. APPLICANTS
(a) NAME
(b) NATIONALITY
(c) ADDRESS


1. MAHINDRA & MAHINDRA LTD.
2. M/S. M.N. RAMARAO & COMPANY
1. Indian Company registered under the provisions of
The Companies Act, 1956
2. An Indian Partnership Company
1. Mahindra Towers, Worli, MUMBAI - 400 018 Maharashtra State, India
2. 18, Victoria Road, Viveknagar P.O. BANGALORE -560 047, Karnataka State, India

3. PREAMBLE TO THE DESCRIPTION

PROVISIONAL
The following specification describes th invention.

COMPLETE
3 The following specification
particularly describes the invention and the manner in which it is to be performed.

4 DESCRIPTION (Description starts from page 2)
5. CLAIMS: 7 Nos.
6. DATE AND SIGNATURE: Given at the end of last page of specification.
7. ABSTRACT OF THE INVENTION: At the end of the specification

Title of invention: Method & apparatus for an improved air filter system for railway locomotives
Field of invention: The present invention is related to the air filters. More particularly the present invention is related to the air filters used in railways for the air induced by the locomotive engines.
Prior art: Currently, railway air induction filters are made of a pre-cleaner, a secondary filter, and a dust-scavenging pump. The pre-cleaner is a series of cyclonic vanes that reside on a frame. As air enters the pre-cleaner frame, it is forced to undergo a cyclonic flow, allowing for heavier dust particles to be shed before entering the secondary filter. A dust-scavenging pump that resides below the pre-cleaner frame sucks out the heavier particles of dust that get ejected from the pre-cleaner. Given the limited ability the pre-cleaner has to remove airborne contaminants due to its design, a lot of the dust gets sent to the secondary filter. This results in the secondary filter getting choked sooner than intended an in addition the loaded secondary filter sheds finer particles of dust into the internal combustion engine, resulting in a higher than acceptable collection of silica in the engine oil. A higher level of dust in the engine oil implies that there is higher than acceptable levels of dust in the internal combustion engine, which could potentially cause damage to the engine.
A secondary filter that chokes sooner than originally desired needs to be replaced sooner than desired. Since current secondary filters are not recyclable, they need to be discarded. Given the large volumes of filters the Railways discards, this can amount of an expense of tens of millions of rupees in new purchases. The
2

discarded material is made from glass fiber, is thrown into a
i
landfill. Glass fiber media is not biodegradable. Deficiencies or drawbacks of prior art:
• Efficiencies are low as measured by an increased presence of
silica in the engine oil
i
• Higher pressure drop across the pre cleaner
• Higher cost due to casting type used for filter system
• Heavy, so difficult to handle while servicing
• Secondary fine filters, which are currently in use, have a low dust holding capacity calling for frequent change.
• Secondary fine filters are not reusable. Once they reach their life, they are thrown into a landfill.
• Dust holding capacity is low since a lot of the airborne contaminants impinge on the secondary filter and don't get ejected by the pre-cleaner
• The necessity of a "scavenging pump" that sucks heavier particles of dust that is ejected by the pre-cleaner. A scavenging pump is expensive. Thus it is the need of the hour to provide a cost effective, Eco-friendly air filter that overcomes the drawbacks posed by the current railway air intake filter.
Summary and objects of the invention: The primary object of
the present invention is to provide an improved air filter, which is
highly efficient and has excellent dust holding capacity and yet
demonstrates very low-pressure drop across the filter.
Another objective of the present invention is of developing an air
filter^ that is capable of holding large volumes of pollutants.
Yet another object of the present invention is to provide a filter
that is resistant to water and any accidental ingestion of water into
3

the housing shall not in any way affect its filtration characteristics or performance.
Yeti another objective of the present invention is removal of airborne contaminants in the inducted air as dictated by the need to minimize wear in engine components undergoing relative motion.
Yet another objective of present invention is providing a mechanism for "progressive filtration" of the air entering the engine and to provide an "extended performance filter" that extends the servicing interval, thereby bringing down operating/maintenance costs for railways. It also reduces the overall outlay for air filter replacement.
Yet another object of this invention is to provide a cost effective, eco-friendly air filter that has excellent filtration efficiency, high dust holding capacity and that can be cleaned and re-used. The present invention, "method & apparatus for an improved air filter system for railway locomotives" provides FPCP (Flexible Porous Cellular Plastic) foam air filter media and an improved method of construction of the filter housing to make maximum use of the space available, provides optimal dust holding capacities & efficiencies, yet keeps costs down. FPCP media by its very nature is excellent for air filtration since it has 97% void volume. This enables capturing various kinds of airborne contaminants, while providing very low restriction to the flow of air. The air filter system is also designed to provide good support to the foam but at the same does time not add significantly to the pressure drop. This design can also be considered as an "Extended Performance Filter" which will not require servicing/cleaning for a substantial extended period of time.
4

The present invention comprises of the following:
1. A set of inverted baffles, which allow heavier particles to be ejected out. The baffles also provide protection to the FPCP media from sparks flames etc.
2. An intermediate "Progressive Filter" with varying layers of FPCP porosities that allow for much of the dust, not removed by the baffles to be captured.
3. A FPCP based secondary filter that captures more than 99.4% of all particles that were not captured by the intermediate filter.
Statement of invention: 1. Method & apparatus for an improved air filter system for railway locomotives in its first configuration comprising of,
1. pre - cleaner comprising
a. baffles,
b. inlet support/mesh,
2. intermediate filter foam pack comprising
c. outlet support/mesh,
d. housing and
3. secondary fine filter;
• at least one set of arc shaped inverted baffles (1.1) being incorporated to trap the heavy dust particles as well as the sparks that are coming out from the exhaust during the passage of the locomotive through a tunnel; air being made to change its direction with the use of baffles due to which the heavier particles get collected on the surfaces of the baffles and being taken out from the housing, dust particles collecting on the surface of the baffle and falling down to the dust collecting chamber which is just below the baffles and a ventury
5

arrangement which creates a negative pressure when the
locomotive is in motion (Bernoulli's Principle) that helps in
taking away the heavier dust particles, eliminating the need of
scavenging pump; and also reducing the loading of dust on the
primary foam pack (1.4);
inlet support/mesh being wide metal meshed surface (1.3)
providing support to the primary foam pack (1.4) from the front, behind the baffles, offering almost no resistance for the air flow,
ensuring that the filter pack as held in position; the said meshed
surface (1.3) being fixed to the housing (1.2);
intermediate filter foam pack comprising primary foam pack (1.4),
comprising of at least 2 layers of FPCP material of PPI 10 (PPI -
pores per linear inch) being used as a pre filter to trap the coarse
dust particles, foam media being impregnated uniformly with tacky
oil (e. g. SAE 20W40 oil or the like), which acts as a tackifier
enhancing the filtration efficiency and dust holding capacity, the
j
primary foam pack being reusable after cleaning;
out let support (1.7) being a wide metal meshed surface that
provides support to the foam filter pack from back side, ensuring
that the foam pack is held in position; the said out let support
(1.7) being permanently fixed oh to the housing (1.2);
the housing (1.2) being a metal case that houses all the features
described above;
i
a secondary fine filter (1.5) comprising of the finer FPCP media (1.6), PPI 60 (1.6a) through PPI 110 (1.6b) used being efficient enough to trap the 5 and 10 micron particles and more of 1 micron particles; the media being impregnated with tacky oil to make the FPCP media more efficient; the fiber glass media (not shown in the drawings) being provided on either side of FPCP media (1.6) to
6

protect it from the back fire; the secondary filter (1.5) being a filter type selected from bag type and the cassette type filters. 2. Method & apparatus for an improved air filter system for railway locomotives in its second configuration comprising of-
1. pre cleaner - cyclonic pre cleaner,
2. secondary filter comprising,
a. intermediate foam pack,
b. secondary bag / cassette type fine filter.
the arrangement comprising an inflow cyclonic separator in the
initial stage to remove heavier particles having at least 3 stationary

blades (2.1) per cyclonic circular tube (2.2) and a diffuser (2.3)
thereafter, the dust collected in the pre cleaner being removed
using a scavenging pump e. g. ventury mechanism; an
intermediate coarse FPCP filter media (PPI 10 - PPI 30) (2.4) in a
cassette type housing (2.8) being attached to the secondary filter
and a fine filter (2.5), bag type, cassette type or the like to
capture finer particles; the support mesh (2.6) being provided
from the back side so as to support the filter bags from the rear
side; the bag / cassette filter being assembled in a box type
housing (2.7).
Description of the figures:
Fig. 1 shows the graph of the pressure drop v/s the dust held for
the present invention.
Fig. 2 shows the side view of the present invention in its
configuration 1.
Fig 3 shows the front view of the present invention in its
configuration 1.
Fig, 4 shows sectional view Y-Y with reference to Fig. 3 of the
present invention.
7

Fig. 5 shows enlarged detail "P" showing the details of the baffles.
Fig. 6 shows side view of the post filter according to the present
invention.
Fig. 7 shows front view of the post filter according to the present
invention.
Fig. 8 shows sectional view with reference to Fig. 7.
Fig .9 shows details of the filter media according to present
invention.
Fig. 10 shows the front view of the present invention in its second
configuration.
Fig. 11 shows side view of the pre-filter according to the second
configuration of the present invention.
Fig. 12 shows the front view of the post filter according to the
second configuration of the present invention.
Fig. 13 shows sectional view A-A with reference to Fig. 12.
Fig. 14 shows detail "X" with reference to Fig. 13.
Description: The foregoing objects of the invention are
accomplished and the problems and shortcomings associated with
prior art techniques and approaches are overcome by the present
invention as described bellow in the preferred embodiment.
This invention is illustrated in the accompanying drawings, through
out which like reference letters indicate corresponding parts in the
various figures.
The present invention is described bellow in its two configurations.
Configuration 1: The first configuration comprises of,
2. Pre - Cleaner comprising
a. Baffles,
b. Inlet support/Mesh,
3. Intermediate Filter Foam Pack comprising
8

a. Outlet support/mesh
b. Housing and
4. Secondary Fine Filter
• Baffles
One set of arc shaped inverted baffles (1.1) is incorporated to trap the heavy dust particles as well as the sparks that are coming out from the exhaust during the passage of the locomotive through a tunnel. Air is made to change its direction with the use of baffles due to which the heavier particles get collected on the surfaces of the baffles and will be taken out from the housing. The baffle design is such that, it eliminates the need of scavenging pump. Dust particles collect on the surface of the baffle and will fall down to the dust collecting chamber which is just below the baffles and a ventury arrangement which creates a negative pressure when the locomotive is in motion (Bernoulli's Principle) that helps in taking away the heavier dust particles. The baffles reduce the loading of dust on the primary foam pack and hence, increase the cleaning interval of the primary foam pack.
• Inlet support/Mesh
It is a wide metal meshed surface (1.3) that provides support to the primary foam pack from the front, behind the baffles. It offers almost no resistance for the airflow. It ensures that the filter pack is held in position and does not allow the primary foam pack to shift or fall during the real life condition. It is bolted to the flange in six positions provided in the housing.
• Intermediate Filter Foam Pack
Primary foam pack (1.4), consisting of 2 layers of FPCP material of PPI 10 (PPI - pores per linear inch) of combination of 40mm and
9

50mm thickness, is used as a pre filter to trap the coarse dust particles. Foam media is impregnated uniformly with SAE 20W40 oil, which acts as a tackifier that enhances the filtration efficiency and dust holding capacity. The quantity of oil applied is 50% to 100% of the weight of the foam pack. As the thickness range of the foam pack of 50mm to 100mm is used, later part, of the filter automatically acts as finer media even though the. coarse foam media is being used. This feature of the foam helps in trapping most of the finer particles too and hence increases the life of the secondary fine filter. The foam pack not only cleans the intake air but also makes the air flow more laminar. In addition to these functions it also dampens the noise, which helps in reducing the air intake noise level. The primary foam pack can be cleaned and reused after uniform application of oil. The test results of the pre-cleaner is given below,

InitialPressureDrop Arrestance Cumulative Particle Size Analysis (CPSA)
1pm 5pm 10pm
79 mmWG 96.7% 47.2% 94.3% 94.5%
• Outlet support/Mesh
Outlet support (1.7) is a wide metal meshed surface that provides support to the foam filter pack from backside. It also ensures that the foam pack is held in position and does not allow the foam pack to shift around during real life condition. It is permanently fixed on to the housing.
10

• Housing
It is a metal case that houses all the features described above. The outside dimensions of the housing (1.2) are kept same as that of the existing pre - cleaner. It is lighter and cheaper than the existing cyclonic pre - cleaner.
• Secondary Fine Filter
These are the fine filters to trap finer particles that escape from the pre - cleaner. The finer FPCP media (1.6), PPI 60 (1.6a) through PPI 110 (1.6b) are used which offers less resistance to the air flow and are efficient enough to trap the 5 and 10 micron particles and more of 1 micron particles. The media is impregnated with tacky oil, which makes the FPCP media more efficient. The fiberglass media (not shown in the drawings) is provided on either side of FPCP media to protect it from the backfire. The dust holding capacity of this type of filter is more compared to any other industrial media. Better the dust holding capacity, more will be the service intervals. It is also an eco friendly filter since it is washable and reusable unlike the conventional industrial media, which are dumped into landfills. The secondary filter (1.5) is selected from bag type and the cassette type filters or the like. Configuration 2: The second configuration of the Air Intake system comprises of,
2. Pre cleaner - Cyclonic pre cleaner,
3. Secondary Filter comprising,
a. Intermediate foam pack,
b. Secondary bag / cassette type fine filter.
The arrangement includes an inflow cyclonic separator in the initial stage to remove heavier particles; which has at least 3 stationary blades (2.1) per cyclonic circular tube (2.2) and a diffuser (2.3)
11

thereafter. The dust collected in the pre cleaner can be removed using a scavenging pump or the ventury mechanism. An intermediate coarse FPCP Filter media (PPI 10 - PPI 30) (2.4) in a cassette type housing (2.8) is attached to the secondary filter and a bag type or cassette type fine filter (2.5) to capture finer particles. The primary foam pack (2.4) has the thickness in the range of 30 mm to 80 mm. The quantity of oil applied to primary foam pack (2.4) is in the range of 50% to 100% of the weight of the foam pack. The support mesh (2.6) is given from the backside, which
i
supports the filter bags from the rear side. The bag / cassette filter is assembled in a box type housing (2.7). The construction of the configuration 2 is as shown in the Figures 10, 11, 12 13 and 14.
The difference between the two configurations is, o The pre cleaner is of Cyclonic type in the configuration 2 instead
of baffle type as in configuration 1. o The intermediate coarse FPCP filter pack is integrated with the
secondary filter housing in the configuration 2.
ADVANTAGES: The advantages of the present invention over the prior art are listed bellow.
1. The pressure drop across the filter is considerably lower than current filters.
2. Dust holding of said filter is much higher than currently used filters. This design can also be considered as an "Extended Performance Filter" which will not require servicing for a substantial extended period of time, thereby bringing down the operational costs for the Railways
12

3. the filter system can be cleaned and re-used. This will bring
down the acquisition / capital costs of new filters for the
Railways • The new construction does not require the use of a scavenging
pump,
bringing down the acquisition / capital costs for the Railways. The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment.
Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or matter. The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention; which is defined by the scope of the following claims.
13

We Claim
1. Method & apparatus for an improved air filter system for railway locomotives in its first configuration comprising of, 2. pre - cleaner comprising
a. baffles,
b. inlet support/mesh,
2. intermediate filter foam pack comprising
c. outlet support/mesh,
d. housing and
3. secondary fine filter;
at least one set of arc shaped inverted baffles (1.1) being incorporated to trap the heavy dust particles as well as the sparks that are coming out from the exhaust during the passage of the locomotive through a tunnel; air being made to change its direction with the use of baffles due to which the heavier particles get collected on the surfaces of the baffles and being taken out from the housing, tunnel; dust particles getting collected on the surface of the baffle and falling down to the dust collecting chamber which is just below the baffles and a ventury arrangement creating a negative pressure when the locomotive is in motion (Bernoulli's Principle) helping in taking away the heavier dust particles; the baffles thus eliminating the need of scavenging pump and also reducing the loading of dust on the primary foam pack (1.4); inlet support/mesh being wide metal meshed surface (1.3) providing support to the primary foam pack (1.4) from the front, behind the baffles, offering almost no resistance for the air flow, ensuring that the filter pack as held in position; the said meshed surface (1.3) being removably fixed to the housing (1.2);
I4 5 DEC2006

intermediate filter foam pack comprising primary foam pack (1.4), comprising of at least 2 layers of FPCP (Flexible Porous Cellular Plastic) material of PPI 10 (PPI - pores per linear inch) being used as a pre filter to trap the coarse dust particles, foam media being impregnated uniformly with tacky oil (e. g. SAE 20W40 oil or the like), which acts as a tackifier enhancing the filtration efficiency and dust holding capacity, the primary foam pack being reusable after cleaning;
out let support (1.7) being a wide metal meshed surface that provides support to the foam filter pack from back side, ensuring that the foam pack is held in position; the said out let support (1.7) being permanently fixed on to the housing (1.2); the housing (1.2) being a metal case that houses all the features described above;
a secondary fine filter (1.5) comprising of the finer FPCP media (1.6), PPI 60 (1.6a) through PPI 110 (1.6b) used being efficient enough to trap the 5 and 10 micron particles and more of 1 micron particles; the media being impregnated with tacky oil to make the FPCP media more efficient; the fiber glass media (not shown in the drawings) being provided on either side of FPCP media (1.6) to protect it from the back fire; the secondary filter (1.5) being a filter type selected from bag type and the cassette type filters. 2. Method & apparatus for an improved air filter system for railway locomotives in its second configuration comprising of-
2. pre cleaner - cyclonic pre cleaner,
2. secondary filter comprising,
c. intermediate foam pack,
d. secondary bag / cassette type fine filter.
15

the arrangement comprising an inflow cyclonic separator in the initial stage to remove heavier particles having at least 3 stationary blades (2.1) per cyclonic circular tube (2.2)'and a diffuser (2.3) thereafter, the dust collected in the pre cleaner being removed using a scavenging pump e. g. ventury mechanism; an intermediate coarse FPCP filter media (PPI 10 - PPI 30) (2.4) in a cassette type housing (2.8) being attached to the secondary filter and a fine filter (2.5), bag type, cassette type or the like to capture finer particles; the support mesh (2.6) being provided from the back side so as to support the filter bags from the rear side; the bag / cassette filter being assembled in a box type housing (2.7).
3. Method & apparatus for an improved air filter system for railway locomotives as claimed in claim 1 wherein, the primary foam pack (1.4) has the thickness in the range of 50 mm to 100 mm.
4. Method & apparatus for an improved air filter system for railway locomotives as claimed in claim 1 wherein, the quantity of oil
i
applied to primary foam pack (1.4) is in the range of 50% to 100% of the weight of the foam pack.
5. Method & apparatus for an improved air filter system for railway locomotives as claimed in claim 2 wherein, the primary foam pack (2,4) has the thickness in the range of 50 mm to 100 mm.
6. Method & apparatus for an improved air filter system for railway locomotives as claimed in claim 2 wherein, the quantity of oil applied to primary foam pack (2.4) is in the range of 50% to 100% of the weight of the foam pack.
7. Method & apparatus for an improved air filter system for railway locomotives as claimed in claim 1 and claim 2 as substantially

described hereinbefore, with reference to the accompanying drawings.

th
Dated this 30™ day of November 2006


M.D. Bhate Agent for the applicant

17

Abstract
Method & apparatus for an improved air filter system for railway locomotives in its first configuration comprising of, 1. pre - cleaner comprising
a. baffles,
b. inlet support/mesh,
2. intermediate filter foam pack comprising
c. outlet support/mesh,
d. housing and
3. secondary fine filter.
The invention in its second configuration comprising of-
1. pre cleaner - cyclonic pre cleaner,
2. secondary filter comprising,
a. intermediate foam pack, secondary bag / cassette type fine filter.
The pre filter and fine filter being made of FPCP (Flexible Porous Cellular Plastic) material.
5 DEC 2006

Documents:

1510-mum-2005-abstract (complete).doc

1510-mum-2005-claims (complete).doc

1510-mum-2005-claims (complete).pdf

1510-MUM-2005-CLAIMS(AMENDED)-(21-3-2011).pdf

1510-MUM-2005-CLAIMS(GRANTED)-(28-9-2011).pdf

1510-mum-2005-correspondence(7-9-2007).pdf

1510-MUM-2005-CORRESPONDENCE(IPO)-(28-9-2011).pdf

1510-mum-2005-correspondence-received.pdf

1510-mum-2005-description (complete).pdf

1510-mum-2005-description (provisional).pdf

1510-MUM-2005-DESCRIPTION(GRANTED)-(28-9-2011).pdf

1510-mum-2005-drawings.pdf

1510-MUM-2005-FORM 18(7-9-2007).pdf

1510-MUM-2005-FORM 2(GRANTED)-(28-9-2011).pdf

1510-MUM-2005-FORM 2(TITLE PAGE)-(21-3-2011).pdf

1510-MUM-2005-FORM 2(TITLE PAGE)-(COMPLETE)-(5-12-2006).pdf

1510-MUM-2005-FORM 2(TITLE PAGE)-(GRANTED)-(28-9-2011).pdf

1510-MUM-2005-FORM 2(TITLE PAGE)-(PROVISIONAL)-(7-12-2005).pdf

1510-MUM-2005-FORM 3(21-3-2011).pdf

1510-MUM-2005-FORM 3(5-12-2006).pdf

1510-mum-2005-form-1.pdf

1510-mum-2005-form-2 (complete).doc

1510-mum-2005-form-2 (complete).pdf

1510-mum-2005-form-2 (provisional).doc

1510-mum-2005-form-2 (provisional).pdf

1510-mum-2005-form-26.pdf

1510-mum-2005-form-3.pdf

1510-mum-2005-form-5.pdf

1510-MUM-2005-REPLY TO EXAMINATION REPORT(21-3-2011).pdf

1510-MUM-2005-SPECIFICATION(AMENDED)-(21-3-2011).pdf

1510-mum-2006-abstract (complete).pdf

abstract1.jpg


Patent Number 249076
Indian Patent Application Number 1510/MUM/2005
PG Journal Number 39/2011
Publication Date 30-Sep-2011
Grant Date 28-Sep-2011
Date of Filing 07-Dec-2005
Name of Patentee MAHINDRA & MAHINDRA LTD.
Applicant Address MAHINDRA TOWERS, WORLI, MUMBAI-400 018,
Inventors:
# Inventor's Name Inventor's Address
1 NARAYAN MANEPALLY 54/3/B, EGIPURA MAIN ROAD, VIVEKNAGAR P.O. BANGALORE-560 047.
2 SUJITH KUMAR 54/3/B, EGIPURA MAIN ROAD, VIVEKNAGAR P.O. BANGALORE-560 047.
3 PRAKASH RAO MALATHKAR 89, M.I.D.C., NASHIK-422 007.
PCT International Classification Number F02M35/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA