U.S. patent application number 11/019602 was filed with the patent office on 2005-05-12 for magnetic fluid filter.
Invention is credited to Elsegood, Stewart D..
Application Number | 20050098490 11/019602 |
Document ID | / |
Family ID | 26708214 |
Filed Date | 2005-05-12 |
United States Patent
Application |
20050098490 |
Kind Code |
A1 |
Elsegood, Stewart D. |
May 12, 2005 |
Magnetic fluid filter
Abstract
A magnetic fluid filter for filtering metallic particles from a
fluid flow system. The filter comprises a magnetic array, a central
support for the magnetic array, and arm pieces for positioning the
effective range of the magnetic array in a fluid flow environment.
The magnetic array includes a plurality of disc shaped magnets
arranged with poles in opposition, interleaved with the arm pieces
and disc shaped pole pieces.
Inventors: |
Elsegood, Stewart D.;
(Balmoral Beach, AU) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET
FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
26708214 |
Appl. No.: |
11/019602 |
Filed: |
December 21, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11019602 |
Dec 21, 2004 |
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10277529 |
Oct 21, 2002 |
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6835308 |
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10277529 |
Oct 21, 2002 |
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10032276 |
Dec 21, 2001 |
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Current U.S.
Class: |
210/222 ;
210/223 |
Current CPC
Class: |
B03C 1/286 20130101;
F02M 27/045 20130101; C02F 1/488 20130101 |
Class at
Publication: |
210/222 ;
210/223 |
International
Class: |
C02F 001/48 |
Claims
What is claimed is:
1. A magnetic filter apparatus comprising: a plurality of magnets
arranged in a like-pole to like-pole orientation; a plurality of
pole pieces, interleaved between said magnets, thereby creating a
magnified magnetic attraction adjacent said pole pieces; a
plurality of arm pieces, extending substantially radially from a
center axis of said filter apparatus; and an assembly piece,
configured to support said plurality of magnets, said plurality of
pole pieces, and said plurality of arm pieces.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/277,529 entitled "MAGNETIC FLUID FILTER"
filed on Oct. 21, 2002, which is a continuation-in-part of U.S.
patent application Ser. No. 10/032,276 entitled "MAGNETIC FLUID
FILTER" filed on Dec. 21, 2001. The disclosure of the
above-described filed applications are hereby incorporated by
reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a filter, and more
particularly a magnetic filter for removing solid particles from a
fluid.
[0004] 2. Description of the Related Art
[0005] It is common practice to use fluids to lubricate moving
parts of mechanical systems. Foreign particles are often shed by
the mechanical system in operation into the lubricating fluid where
it can cause wear and damage to the operating system and its
components. Many mechanical systems already make use of primary
filters to remove foreign particles from the lubricating fluid of
the system such as oil filter cartridges in an automobile engine or
transmission system.
[0006] The majority of contaminant particles in a mechanical system
are metallic in nature and therefore subject to magnetic
attraction. For this reason, others have attempted to integrate
magnets with conventional filters to provide removal of metallic
particles. However, prior magnetic filters were typically limited
in that their design was specific for a particular application
environment. For example, the majority of current magnetic filters
are limited to their application to engine oil filtration systems
within automobiles. Moreover, such filters are typically connected
to the external flow path of the fluid to be filtered.
[0007] Accordingly, it would be advantageous for a magnetic filter
to have the capability of being integrated into any fluid system
requiring filtering of metallic particles, and for the magnetic
components in the filter to be in closer proximity to the direct
flow of the fluid through the filtering device.
SUMMARY OF THE INVENTION
[0008] A filter apparatus comprises a magnetic array for removing
metallic particles from a fluid, the magnetic array comprising a
plurality of magnets and a plurality of pole pieces, wherein the
pole pieces are interleaved between the magnets, a plurality of arm
pieces extending substantially radially from a center axis of the
filter apparatus, and an assembly piece configured to support the
magnets, pole pieces, and arm pieces.
[0009] In the filter apparatus, the plurality of magnets can be
disc shaped, and the pole pieces can have a larger diameter than
the magnets. The magnetic array may comprise 3, 4, 5 or 6 magnets
disposed a distance apart from one another so that a polar
repulsion force is maintained between each magnet and its nearest
neighbor magnet.
[0010] The arm pieces can be configured to reversibly mount the
filter apparatus to the inside of a conventional oil filter, a
filter cartridge element, a fluid reservoir, a transmission fluid
flow line, or a hydraulic fluid flow line. The arm pieces may
comprise a disc shaped center and a plurality of arms extending
substantially radially from the disc shaped center.
[0011] A fluid filter apparatus comprises a magnetic array,
comprised of a plurality of magnets arranged in a like-pole to
like-pole orientation, wherein the magnets are separated by a
plurality of pole pieces. The fluid filter apparatus further
comprises a plurality of arm pieces extending substantially
radially from a center axis of said magnetic array, and a support
piece configured to support the magnetic array in a fluid flow path
such that fluid is allowed to flow over the magnetic array and pass
within the effective magnetic range of the array in order to
extract ferrous contaminants from the fluid.
[0012] In the fluid filter apparatus, the fluid can be power
steering fluid, and the center support piece can comprise a rod
configured to support the magnetic array along a center axis. The
rod may also be flexible so as to allow the filter to bend for
insertion in a fluid flow path.
[0013] In the fluid filter apparatus, the pole pieces can have a
larger diameter than that of the magnets, and the arm pieces can
have a disc shaped center and a plurality of arms extending from
the disc shaped center.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a cross-sectional assembly view of one embodiment
of a magnetic fluid filter.
[0015] FIG. 2 is a cross-sectional view of one embodiment of a
magnetic filter.
[0016] FIG. 3 is an illustration of a magnet support piece before
it is folded.
[0017] FIG. 4A is a perspective view of the magnet support piece of
FIG. 3 after a first fold is made.
[0018] FIG. 4B is a perspective view of the magnet support piece of
FIG. 4 after a second fold is made.
[0019] FIG. 5 is a cross section view of the magnetic filter of
FIG. 2 taken along the line 5-5.
[0020] FIG. 6A is a side view assembly stack illustration of a
magnetic array.
[0021] FIG. 6B is a side view of the assembled magnetic array of
FIG. 6A.
[0022] FIG. 7A is a cross sectional side view of an alternative
embodiment of the magnetic filter.
[0023] FIG. 7B is a cut away view of a conventional automobile oil
filter.
[0024] FIG. 7C is a vertical view of the alternative embodiment of
the invention of FIG. 7A.
[0025] FIG. 8 is a cut away view of the conventional oil filter of
FIG. 7B with the magnetic filter of FIG. 7A installed.
[0026] FIG. 9 is a cross-sectional assembly view of one embodiment
of a magnetic filter.
[0027] FIG. 10 is a perspective assembly view of the magnetic
filter of FIG. 9.
[0028] FIG. 11 is a perspective view of the magnetic filter of FIG.
9 in an assembled formation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] Embodiments of the invention relate to a magnetic fluid
filter for filtering metallic particles from a fluid flow system.
One example of such a fluid flow system is a power steering unit in
an automobile. This embodiment includes a cylindrical outer casing
mated to two end pieces for incorporating the filter into a fluid
flow line.
[0030] Inside the magnetic fluid filter is an array of magnets that
is held in place by a support. In one embodiment, the magnetic
array has a plurality of disc shaped magnets separated by "pole
pieces". The magnets, each having a north pole and south pole, are
arranged in a like-pole to like-pole configuration (north to north
and south to south), and separated by the pole pieces. This
configuration of magnetic like-poles creates a large magnetic
gradient that attracts metallic particles to the surface of the
array.
[0031] As can be imagined, embodiments of the invention are not
limited to the specific magnetic array described above. For
example, the magnetic array can include 3, 4, 5, 6 or more magnets
disposed a distance apart from one another so that a polar
repulsion force is maintained between each magnet and its nearest
neighbor magnet.
[0032] The magnet support can be made from a folded and punched
piece of non-magnetic material, such as stainless steel. Notched or
cut out sections within the support provide a nest for the magnetic
array centrally along the length of the case such that fluid
flowing through the case is within the effective range of the
magnetic array. The pole pieces can have a larger diameter than
that of the magnets such that as fluid flows over the array the
pole piece provides a shelter on the downstream side of the pole
piece for the magnetically attracted metallic particles in the
fluid. Alternatively, the pole pieces can have a smaller diameter
than the magnets to provide a reservoir for the magnetically
attracted metallic particles.
[0033] The arrangement of the magnets within the cylindrical case
allows fluid flow in either direction. In addition to
bi-directional fluid flow, because there is no device that can be
filled or blocked, the filter can allow full flow of fluid at all
times.
[0034] FIG. 1 is a cross-sectional assembly view of a magnetic
fluid filter 100. The filter 100 comprises a hollow cylindrical
case 102 that is preferably made of a non-magnetic material. The
case 102 has two circular open ends 104A, B into which a first and
second hollow end pieces 106, 108 can be secured. The end pieces
106, 108 allow for installment of the filter 100 into any fluid
line such that the end pieces 106, 108 provide secure attachment to
the fluid flow system and an inlet and/or outlet whereby fluid is
allowed to flow inside the case 102 of the filter 100. The end
pieces 106, 108 can be of a screwed connection type, barb
connection, or direct to hose swage connection, or any combination
thereof.
[0035] The case 102 allows containment of fluid flow over a
magnetic array 110 that is disposed within the case 102. The
magnetic array 110 includes a series of magnets 112A-D arranged in
a like-pole-to-like-pole arrangement, whereby each magnet is
separated by a pole piece 114A-C. The magnets 112 and pole pieces
114 are preferably disc shaped. In addition, the pole pieces 114
can vary in width, and in one embodiment are much more narrow than
the magnets 112. The pole pieces 114 can be manufactured from a
magnetic material, such as iron or steel, and are slightly larger
in diameter than the magnets 112A-D in order to provide shelter on
the downstream side of the pole piece. The magnetic array 110 will
be discussed in further detail with respect to FIGS. 6A and 6B. A
magnet support 116 is also illustrated in FIG. 1, and is configured
to support the magnetic array 110 within the case 102.
[0036] A cross-sectional view of the assembled magnetic filter 100
is shown in FIG. 2. The magnet support 116 is contained within the
case 102 by contacting the inner wall of the case 102, but allowing
for end caps or means for secure attachment of the case 102 to a
fluid flow system. As shown, the assembled array 110 is supported
within the case 102 by the support 116 extending the length of the
case 102. Also shown in FIG. 2 are the end pieces 106, 108
installed on the filter 100 to provide a fluid inlet and outlet to
the interior of the case 102.
[0037] As can be seen in FIG. 2, as fluid enters the filter 100 it
flows over the magnetic array 110 and through the case 102.
Therefore, irrespective of the direction of fluid flow, metal
particles will be filtered out of the fluid by the magnetic array
110. The filter 100 can therefore be installed in a fluid path
irrespective of the direction of fluid flow.
[0038] Referring now to FIG. 3, in this embodiment the magnet
support 116 is comprised of a punched, and then folded flat piece
of stainless steel or other non-magnetic material. The magnet
support 116 is formed by punching two voids 302, 304 in a flat
piece of steel 307 so that when it is folded, it will have a length
corresponding to that of the array 110, and a width corresponding
to the diameter of the array 110 (See FIGS. 4 and 5). A plurality
of notches 310A-L, having a width corresponding to the width of the
pole piece 114, and a depth corresponding to the difference in
radius between that of the pole piece 114 and that of the magnet
112, are formed in the inner edges 314 of the magnet support 116.
As can be imagined, the larger diameter pole pieces 114A-C can then
be mounted inside of the notches 310A-L when the steel 307 is
folded into the proper formation. Of course, it should be realized
that the magnetic support is not limited to being formed from
steel, and can be made from any support material, magnetic or
non-magnetic, such as metal or plastic.
[0039] Once the proper notches are formed in the steel 307, a
first, right angle fold is made along the longitudinal center-line
of the punched piece of steel 116 so as to form corners 402, 404 on
either end of the punched piece 116 as indicated in FIGS. 4A, B. A
second, 180.degree. angle fold is then made along a center axis of
the punched piece 116, perpendicular to the axis of the first fold,
such that the two corners 402, 404 formed from the first fold are
adjacent to one another.
[0040] Referring back to FIG. 3, when the magnet support 116 is
folded to its final geometry surrounding the magnetic array 110,
the magnetic array 110 is secured along four longitudinal inner
edges 314 of the support on the peripheral surfaces of the magnets
112A-D and pole piece 114A-C. The outer surfaces of the magnets
112A-D and pole pieces 114A-C are then in contact with the inner
edges 314 of the magnet support 116. When the folded magnetic
support 116 is placed within the case 102 (See FIGS. 2 and 5), the
magnetic disks 112A-D and pole pieces 114A-C are held in place by
the inward force placed on the support 116 from the case 102.
[0041] A cross-section of the magnetic array 110 supported in the
case 102 along line 5-5 is shown in FIG. 5. As can be seen in FIG.
5, the folded magnet support 116 forms an "X" shape along the cross
section. Of course, the magnet support 116 can be of any geometry,
such as any frame having a void corresponding to the shape and
dimensions of the magnetic array 110 but not fully encapsulating
the array 110, so as to support the array 110 in an effective
position in the fluid flow path through the filter 100.
[0042] The magnetic array 110 will now be discussed in further
detail with reference to FIGS. 6A and 6B. The
like-pole-to-like-pole arrangement of the magnets 112A-D creates a
magnified magnetic attraction at the area where the poles are held
apart by the pole piece 114A-C. The design presented by the
magnetic array 110 increases the amount of non-homogeneous magnetic
field produced by a fixed volume of magnetic material.
[0043] A magnetic field gradient is necessary to attract
ferro-magnetic or metal particles, and to hold them in the filter
100. The magnetic attraction force provided by the magnetic field
gradient should be greater than competing forces. In this case the
competing forces are provided by gravity and fluid flow through the
filter 100, wherein even if the fluid flow is great, the filtered
particles are simply spread along the length of the array 110. One
embodiment of the invention can obtain field gradients as high as
30 T/m close to the pole pieces 114A-C in the array 110. An
additional advantage to the array 110 is that it can be more
powerful than expensive rare earth magnets, and it is also not
affected in performance by heat, as are rare earth magnets. Of
course, it will be appreciated that any type of magnet can be used
in the array 110.
[0044] FIG. 7A illustrates a cross sectional view of an alternative
embodiment of a magnetic filter 700. The filter 700 comprises the
magnetic array 110 as described previously, however a sleeve 702
(of plastic, for example) is disposed around the exterior of the
array 110. As shown, the sleeve 702 has a plurality of elastic
branches or spines 704 protruding from its outer surface. The
spines 704 are designed to be folded back along the sleeve 702 such
that the filter 700 can be slidably inserted into the center return
shaft of a conventional oil filter 706 (FIG. 7B).
[0045] FIG. 7C provides a top view of the filter 700 and its
plurality of protruding spines 704 protruding from the sleeve 702.
Alternatively, the spines 704 can be directly mounted or
incorporated with the magnetic filter 700 along an outer surface of
the case 702.
[0046] FIG. 8 is a cut-away side view of the filter 700 installed
in the conventional oil filter 706. The spines 704 are configured
to spring outward when installed in the oil filter 706 to hold the
filter 700 in position. As oil flows past the magnetic surface of
the array 110 metal contaminants are collected on the filter
700.
[0047] An additional embodiment of a magnetic filter 800 is
illustrated in FIG. 9, wherein FIG. 9 is a cross-sectional assembly
view of the magnetic filter 800. Similar to the magnetic array 110,
the magnetic filter 800 comprises an array 801 of a series of
magnets 802A-D having a cylindrical shape, wherein the magnets
802A-D are arranged in a like-pole-to-like-pole configuration, and
are separated by a plurality of disc shaped pole pieces 804A-C,
similar to pole pieces 114. In one embodiment, the pole pieces
804A-C have a greater diameter than the magnets 802A-D, so as to
provide shelter for contaminants collected on the magnetic filter
800.
[0048] A plurality of arm pieces 806A-E are positioned in the array
between the magnets 802A-D along with the pole pieces 804A-C, and
at each end of the array 801. The arm pieces 806A-E have disc
shaped centers 807A-E with approximately the same diameter as that
of the magnets 802A-D, and a plurality of holding arms 808
extending radially outward from the disc shaped centers 807A-E so
as to hold the magnetic filter 800 in a substantially fixed
position when mounted into a fluid filter. The arm pieces 806A-E
extend in a substantially radial direction from a center axis 809
of the array 801, and at an angle .theta. of approximately
60.degree. from the center axis 809 of the array 801 in one
embodiment. Of course, the particular angle of each arm, and number
of arms can be changed without departing from the invention. The
arm pieces 806A-E are illustrated in more detail in the perspective
views of FIGS. 10-11.
[0049] As shown in FIG. 9, the magnets 802A-D, pole pieces 804A-C,
and arm pieces 806A-E all have a circular void centered along the
central axis 809 of the array 801 so as to provide a hollow shaft
along the length of the array 801 for accommodation of a center pin
810. The magnets 802A-D have central voids 820A-D, the pole pieces
804A-C have central voids 822A-C, and the arm pieces 806A-E have
central voids 824A-E. During assembly, the center pin 810 is
slidably inserted into the hollow shaft provided along the central
axis of the array 801 so as to assemble the magnets 802A-D, pole
pieces 804A-C, and arm pieces 806A-E. As the center pin 810 is
inserted, the arm piece 806A is positioned flush against an end
piece 812 of the center pin 810. The end piece 812 is preferably
designed to have a diameter larger than that of the hole in the arm
piece 806A.
[0050] To complete the assembly of the magnetic filter 800, a
removable end piece 814 is fixed on the center pin 810 against the
arm piece 806E so as to hold the array 801 on the center pin 810.
The removable end piece 814 can be, for example, a spring clip, a
nut, a cotter pin, or any other part, such that a holding force is
provided between the removable end piece 814 and the end piece 812
to hold the magnets 802A-D, pole pieces 804A-C, and arm pieces
806A-E in a substantially fixed position. In one embodiment, an end
portion of the center pin may be threaded and a complimentary
threaded fastener, such as a nut, can be fastened onto the threaded
center pin.
[0051] FIG. 10 is a perspective assembly view of the magnetic
filter 800, wherein the orientation and angle .theta. at which the
holding arms 808 of the arm pieces 806 extend from the center disc
portion 807 can be seen more clearly. An end portion 826 of the
holding arms 808 preferably has a greater width than a stem portion
828 of the holding arms 808 so as to provide a hooking, or grabbing
point, for the holding arms 808 to attach to a housing or tubing
when the magnetic filter 800 is mounted inside a fluid filter. The
arm pieces 806A-E are preferably made from a bendable or flexible
material, such as a mild steel, such that the arm pieces 806A-E are
able to bend when the magnetic filter 800 is inserted into a fluid
flow environment. Of course, embodiments of the invention are not
limited to arm pieces that are made of any particular type of
material. Nor should this embodiment of the invention be limited to
holding arms of the described configuration. Other configurations
of holding arms such as those that do not have widened end portions
are still within the scope of the invention.
[0052] As illustrated, during assembly, the center pin 810 is
slidably engaged within the central orifices of each filter
component. Accordingly, the center pin 810 is adapted to slide
snugly through the central orifice 824A of the arm piece 806A, then
through the central orifice 820A of the magnet 802A. The center pin
810 is then slid through the central orifice 824B of the arm piece
806B and through the central orifice 822A of the pole piece 804A.
The center pin 810 is then slid through the central orifices of the
remaining parts until it reaches the removable end piece 814.
[0053] FIG. 11 illustrates an assembled magnetic filter 800 wherein
the center pin 810 has been fully engaged within the central
orifices of the arm pieces, magnets, and pole pieces. The end piece
812 of the center pin 810 is mated against the center portion 807A
of the arm piece 806A. Of course it should be realized that this
specific configuration is not the only configuration that is within
the scope of the invention. For example, more or less number of arm
pieces could be positioned within the filter. In addition, the arms
themselves need not be on separate pieces, but could be mounted
directly on the magnets or pole pieces so long as they provide a
holding force for the filter when mounted within a fluid
filter.
[0054] The magnetic filter 800 can be inserted into the case 102 of
the filter 100 to replace the array 110, or the magnetic filter 800
can be installed in a conventional oil filter in a similar fashion
to the magnetic filter 700 (FIG. 8). Additionally, the magnetic
filter 800 can be installed in a transmission power steering fluid
flow line, a replaceable filter cartridge element, a fluid
reservoir, or a hydraulics system fluid flow line to attract and
trap contaminant particles onto the magnetic filter 800 from the
fluids in the flow lines. In one embodiment, the center pin 810 can
be made of a flexible material such that the magnetic filter 800
can bend for easier insertion into a fluid flow line or adaptation
to a curved fluid flow line, thus making the magnetic filter 800
more versatile with regard to application environments.
[0055] Although a preferred embodiment of the filter of the present
invention has been discussed in the preceding section, the
invention is not limited to this embodiment. Other embodiments
which capture the spirit of the invention are also anticipated. The
scope of the invention is not limited to the embodiments discussed
above, but is only limited by the following claims.
* * * * *