US20010006161A1

US20010006161A1 - Magnetic filter and method for purifying and treating liquids using permanent magnetic balls

Info

Publication number: US20010006161A1
Application number: US09/780,556
Authority: US
Inventors: Leonid Tulchinskiy
Original assignee: Individual
Current assignee: Technology Commercialization Corp
Priority date: 1999-10-18
Filing date: 2001-02-12
Publication date: 2001-07-05
Also published as: WO2001028653A1; AU8025800A; US6210572B1

Abstract

A filter for and a method of removal of magnetic particles and treating a liquid with a magnetic field in which a liquid flows through a filter containing permanent magnetic balls tightly packed together so that there is no straight flow path through the filter but only around these magnetic balls. Increased mixing and turbulence of flow coupled with strong intensity of a magnetic field across the direction of the flow promotes better attraction and retention of magnetic particles on the magnetic balls. The filter is particularly useful as a fuel or oil filter for an internal combustion engine. Other advantageous applications include water treatment filters. The filter is capable of removing magnetic particles for an extended period of time without clogging.

Description

CROSS-REFERENCE DATA

This is a continuation-in-part of the patent application No. 09/419,498 filed Oct. 18, 1999 which is incorporated herein by reference in its entirety. [0001]

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a magnetic filter and method for purifying various liquids containing magnetic particles, such as fuels, lubricants, water, hydraulic fluids, and cooling liquids among others. Specifically, the invention relates to filters employing internal magnetic elements in the shape of permanent magnetic balls to trap such magnetic particles and subject the passing by liquid to strong magnetic fields. The filter of the present invention can be used with particular success as a stand alone disposable fuel or oil filter or in combination with other filters for a device with limited energy resources such as an internal combustion engine, as well as in applications such as cooling devices for nuclear and other reactors, etc.

2. Description of the Prior Art

The field of liquid filtration using magnets has been extensively developed in the prior art. In addition to other contaminants, some liquids contain particles that are magnetic in nature. For the purposes of this description, a magnetic particle is defined as a small (generally less then 0.01 of an inch in diameter) solid body that can be attracted and retained on the surface of a magnet. Two types of magnetic filters can be identified—those containing permanent magnets and those containing ferromagnetic inserts (typically made of steel or otherwise containing iron) surrounded by electromagnetic coils. In the second type of the filters, energizing the coil causes metallic inserts to propagate the magnetic field inside the body of the filter and attract metallic contaminants from passing liquid.

An example of the filter with electromagnetic coil can be found in the U.S. Pat. No. 3,539,509 by Heitmann et al. A bed of iron balls is used as a filtering element which is activated by an electromagnetic coil surrounding the housing of the filter. The advantage of this design is the ability to disconnect the electrical energy and therefore discontinue the application of the magnetic field. This is a useful feature for cleaning the filter if necessary. At the same time, in many cases it is more economical to replace the filter then to clean it out. In that case, disposable filters with permanent magnets are preferred. Another disadvantage of electromagnetic coils is the constant need to apply electrical power for the filter to operate, a major contributor to operating expenses and also a source of possible failures, especially in critical applications. Even during momentary interruption of electrical power, the risk exists of sudden release of all trapped material into the flow of liquid with possible catastrophic consequences for the rest of the hydraulic system. There is a need therefore to provide such systems with additional normally closed type valves designed to block the flow of liquid during unexpected power failures, creating added costs and maintenance concerns. There is also a need for an expensive solenoid type coil to be a part of the filter design. A further disadvantage is the lack of flexibility in arranging the orientation of magnetic field of each individual ball inside the filter. For electromagnetic filters, each ball has the same orientation of the magnetic field as all the others—all determined by the electromagnetic coil. In addition, positioning of the electromagnetic coil around the filter determines the orientation of the magnetic field. Changing that orientation is technically very difficult.

Permanent magnet filters are free from the above mentioned limitations. They do not require external energy to operate, allow great flexibility in design and are quite suitable for disposable application. Various well known types of permanent magnets can be used for this application. Ceramic type magnets are the least expensive and therefore most used for industrial and automotive applications.

Prior art magnetic filters include a permanent magnetic element in a shape of a bar magnet inside the filter assembly. For example, U.S. Pat. No. 3,279,607 by Michaelson discloses an automotive oil filter having one or more bar magnets disposed in one or more folds of the filter material, spaced equally around the circumference of the filter housing. Similarly, U.S. Pat. No. 4,501,660 by Hebert relates to an oil filter having a magnetized helical coil disposed in the central core of the filter assembly. An extemally-attached magnetic element is disclosed by U.S. Pat. No. 5,282,963 by Hull, et al. U.S. Pat. No. 5,468,373 by Chou et. al describes a water treatment apparatus containing several spaced apart disk magnets surrounding a flow of water.

These and other filters have inherent disadvantages, caused by the shape and placement of the magnetic elements. It is well known that the strength of magnetic field drops rapidly as the distance from the magnet surface increases. For most designs of the prior art, a straight path for liquid can be determined which takes it between the magnets and therefore creates conditions for magnetic particles to pass by the areas of strong magnetic field. In addition, as the filter of such design accumulates magnetic particles, the resistance to liquid flow increases so as the danger of dislodging the magnetic particles previously accumulated and their undesirable release back into the liquid flow. The need exists for a design of a filter avoiding the straight flow passages and forcing the liquid into tortuous flow paths but without creating substantial resistance to the liquid flow. In other words, there is a need for a magnetic filter with maximum mixing of the passing liquid so that all magnetic particles can be exposed at one time or another to the strong magnetic field and therefore be removed from liquid and retained in the filter.

In addition to filtering, exposing certain liquids to a magnetic field may have other desirable effects. For example, magnetizing of fuels improves their ability to be atomized and provide for better combustion in automobile engines. Passing water through a strong magnetic field is believed to reduce the scaling, or depositing of salts and other compounds on water supplying pipes. An example for water purifying and treating apparatus is found in the U.S. Pat. No. 5,628,900 by Naito. Annular permanent magnets are placed inside the housing of the device also containing magnetite layer of broken up pieces of what is called “magnetite heaped up”. Magnetic lines are oriented in parallel with the flow. A limitation of this device is the irregular shape of the magnetite elements which prevents uniform and consistent exposure of water to the magnetic field.

The need therefore exists for a permanent magnetic filter and a method for purifying and treating of the liquid with magnetic field so that the exposure of the liquid to the magnetic field is maximized while the flow resistance is kept at a minimum throughout the life of the filter. The filter of such design should provide high levels of purification and extended operational time without significant back pressure.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to overcome these and other drawbacks of the prior art by providing a novel filter containing generally round permanent magnets made for example as spherical balls placed across the flow of liquid in such a way that complete exposure of the flow to the permanent magnets is assured, providing excellent conditions for most if not all magnetic particles to be entrapped within the filter.

It is another object of the invention to provide a filter of a relatively small size that is capable of removing from the liquid all magnetic particles, non-magnetic particles of large size, and most of the particles comprising only in part of magnetic materials, all without significant pressure drop across the filter.

It is yet another object of the invention to provide a filter for purification and magnetic treatment of a liquid containing magnetic particles with substantially increased operational time so that the time until clogging of the filter and subsequently the repair or replacement intervals are significantly increased.

It is yet another object of the present invention to provide a filter with all or part of the components being disposable for the ease of replacement.

It is a further object of the invention to provide a filter capable of treating the passing liquid with a magnetic field. For applications such as a fuel filter for the internal combustion engine, treating the fuel with magnetic field improves the process of atomization down the line. Water or other non-magnetic liquid can also be treated with a strong magnetic field to achieve various advantages described above such as for prevention of scale deposits or for preparation of concrete.

It is yet a further object of the invention to provide a method for removal of magnetic particles from a liquid by passing that liquid through a plurality of permanent magnets of generally round shape.

The filter of the invention generally consists of a compartment containing a plurality of generally round permanent magnets placed in the path of liquid flow. Such magnets are preferably made of spherical shape such as magnetic balls. Spherical shape has the advantage of providing the highest magnetic intensity and magnetic gradient and besides is amenable for relatively inexpensive mass production. Should the shape be somewhat non-round such as an oval for example, the filter of the invention would still perform to some degree. Therefore, for the purposes of this description, the term “magnetic ball” is used to include not only a spherical shape in a strict geometrical sense of the word but also all generally round objects with the shape reasonably close to that of a sphere. All deviations from a spherical shape are considered acceptable and included in the definition of the “magnetic ball” as long as such deviations do not cause any substantial detrimental effect on the performance of the filter as compared with the strictly spherical magnetic balls of the same volume and material.

The polarity orientation of each magnet may be random but it is preferred to orient them all in the same direction for further improvement of the filtering efficiency. The best orientation of magnetic field is that which is perpendicular to the direction of the flow. That in itself promotes the secondary effect of the filter which is treating the passing liquid with a strong magnetic field and lowering its viscosity and improving atomizing properties. The plurality of magnetic balls may be typically placed in a housing made preferably of steel or other soft magnetic metals to close the magnetic field loops and conduct it throughout the body of the filter. In one embodiment, all magnetic balls have the same diameter and are packed tightly in a housing having an inlet and an outlet for the passing liquid. In a variation of this embodiment, the spaces between the magnetic balls are filled with a number of magnetic or soft-magnetic balls of progressively smaller diameter to increase the efficiency of the liquid purification without causing substantial pressure drop across the filter. It is preferred in that case to select the smaller magnetic balls to have a diameter of about 0.15 of the diameter of the bigger magnetic balls.

The filter of the invention can be made as a stand alone device or be a part of the multiple stage filtration and treatment apparatus. As such, the design for the housing may vary substantially to accommodate other filtering elements or other parts of the liquid flow system. All such well known design changes are considered to be included in the scope of this invention as long as the filter contains magnetic balls made of a permanent magnet material.

After entering the filter of the present invention, the flow of liquid is passing through the body of the filter containing magnetic balls that create a magnetic field with strong magnetic intensity. Since magnetic balls are packed in such a way that there is no direct path for the liquid flow, it is subjected to multiple turns around the magnetic balls which creates excellent mixing conditions and promotes adhesion of all magnetic particles to the surfaces of the magnetic balls. Other particles such as mixed contaminants having some of magnetic contents as well as the larger non-magnetic particles with the size bigger than the space between the magnetic balls would also be trapped inside the filter. Independently of the filtration process, the strong magnetic field increases the atomization properties of the liquid, reduces temporarily its viscosity, improves the mixing of all the liquid components and additives and may reduce its surface tension. All of these effects are useful in such cases where such treated liquid fuel then proceeds further down the line to the atomizer of the engine so that the ignition and burning characteristics are improved. As the filter accumulates magnetic particles, the spaces between the magnetic balls are reduced but due to the unobstractive geometry of the plurality of magnetic balls the flow resistance is not increased to any significant degree until the filter is about 70% clogged. In other words, the geometry of a plurality of spheres allows for increased operational time of the filter. In our tests with the fuel filters for an automobile, the service life of the filter of the present invention was increased (as measured by the automobile travel distance) from about 15,000 miles to about 50,000 miles.

The filter of the present invention, similar to other filters containing permanent magnets may be designed to be disposable or reusable. To clean such a the filter, a well known method of demagnetizing the permanent magnets can be used when a decaying strength magnetic field of alternating polarity is applied to the permanent magnets reducing their magnetic abilities to zero. Filter can then be cleaned of trapped particles, washed, and permanent magnets can be magnetized again to restore their function. No physical disassembly is required.

For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the subject matter of the present invention and the various advantages thereof can be realized by reference to the following detailed description in which reference is made to the accompanying drawing in which: [0024]
FIG. 1 is a schematic cross-sectional view of the preferred embodiment of the present invention showing the disposable magnetic filter. [0025]

DETAILED DESCRIPTION OF THE MOST PREFERRED EMBODIMENT OF THE INVENTION

A detailed description of the most preferred embodiment of the present invention follows with reference to accompanying drawing on FIG. 1 in which like elements are indicated by like reference numerals. [0026]
According to the design and the method of the present invention, the filter ([0027] 10) consists of a housing (15) having the flow inlet (12) and the outlet (14). Both inlet and outlet may be configured as a barbed connector as shown for example for the inlet (12). Alternately, as shown for the outlet (14), it may be configured as having attachment threads to connect to the lines of the rest of a hydraulic system. Multiple variations of the filter housing and attachments can be used for the filter of the present invention as can be readily apparent to the skilled in the art.
The housing ([0028] 15) of the filter (10) contains a plurality of magnetic balls (20) having spaces (21) therebetween and located between two optional perforated plates (30) and (40). The purpose of plates (30) and (40) is to retain the magnetic balls (20) and to allow some space for flowing liquid to enter the volume occupied by the magnetic balls and likewise to collect together and be directed towards the filter outlet (14) upon leaving the filtration area.
It is preferred that the housing ([0029] 15) contains a plurality of magnetic balls (20) tightly packed to minimize the spaces (21) therebetween. Magnetic balls of the same size form a certain tightly packed pattern similar to one shown on FIG. 1. In order to utilize better the space (21) between the balls (20), additional smaller magnetic balls may be placed in the spaces between the balls (20) (not shown on the drawings). The diameter of these smaller balls should be about 0.15 of the diameter of the bigger magnetic balls to utilize fully the existing spaces between the larger balls but not to separate them apart. They may be optionally made of a soft magnetic material. Such additional magnetic balls would further improve the efficiency of the filter.
In a variation of the device (not shown on the drawing), a second set of magnetic balls may not only have a different diameter but also may be made from a different magnetizable material such as steel. These balls or objects of other shape made from a non-ceramic but still magnetic material would be strongly magnetized in the vicinity of the round permanent magnets and further improve the function of the filter. [0030]
The magnetic poles orientation of individual balls ([0031] 20) may be random but it is preferred to orient all magnetic fields in parallel and further it is preferred to orient them such that the maximum intensity of magnetic field is perpendicular to the direction of flowing liquid. The housing (15) and the perforated plates (30) and (40) may be made of any suitable material but it is preferred to make them out of steel or other similar soft magnetic metal so that they conduct and contain the magnetic field inside the filter (10).
Magnetic balls ([0032] 20) may be made from any available permanent magnet material. The least expensive material for manufacture of spherical magnets is the powder of Strontium or Barium ferrite. From it it is possible to produce inexpensive isotropic magnetic balls with rather low magnetic properties but still useful in some applications. These magnetic balls are more appropriate for disposable magnetic filters. More expensive anisotropic Barium or Strontium ferrite magnets have 2 times greater residual induction and twice greater specific magnetic energy. Reusable magnetic filters are preferably made with magnetic balls of these materials. Samarium Cobalt may also be used. Most expensive anisotropic magnetic balls may be produced on the basis of alloys of the system described by the formula Nd-Fe-B or Nd-Fe-B-Co. They have 5 times greater residual induction and 25 times the greater specific magnetic energy than isotropic ferrite magnets. These magnetic balls can be most advantageously used in reusable magnetic filters for viscous liquids where heating is used to reduce the liquid viscosity. Another advantageous use of filters containing magnetic balls made of such strong magnetic materials is in situations when filtration of undesirable particles containing only weak magnetic materials and in small amounts is needed.
After assembly in the filter housing ([0033] 15), the magnetic balls (20) should be magnetized in a direction of the arbitrary chosen diameter in a constant or pulsed magnetic field. It can be achieved by using electrical solenoids or other well known magnetization method developed in the field of producing permanent magnets. The operation of magnetization can be carried out by both the manufacturer as well as the consumer. In fact, to exclude the influence of a magnetic field emanating from the magnetic balls on systems of navigation and electronic devices it is more preferable to transport the filters to a place of use in non-magnetized condition. If the magnetic balls are magnetized by the manufacturer, then the can be placed in shielding containers made of soft magnetic material to avoid the leakage of strong magnetic fields.
According to the method of the invention, as the liquid passes through the body of the filter ([0034] 10), it makes multiple turns around the balls (20) since there is no direct path through to the outlet (14). Therefore, increased mixing conditions promote better liquid filtration and purification because even the smallest magnetic particles at some point would be passing near a surface of a magnetic ball with strong levels of magnetic field, so that the magnetic forces would be much higher than the forces of inertia or gravity, attracting and trapping even the smallest magnetic particles within the filter (10). At the same time, the spaces (21) between the balls (20) remain opened at all times so that no significant restriction to flow is created. Another advantage of this arrangement is that as the filter (10) accumulates more and more magnetic particles, it remains opened for flow without increasing the resistance for much longer periods of time in comparison to the magnetic filters of the prior art. As can be understood by those skilled in the art, not only magnetic particles are retained by the filter (10) but also mixed particles containing some portion of magnetic materials as well as all magnetic and non-magnetic contaminants with diameters larger then the space between the balls (20). That aspect of the filter (10) relieves downstream hydraulic components from being clogged with these larger particles.
The design of the filter of the invention is particularly suitable for a disposable fuel filter application. In this application, it was determined that the size of magnetic balls should be chosen between about 2 and 20 mm, and preferably between 4 and 7 mm. The total number of magnetic balls should be about 300 which corresponds to a thickness of the pack of magnetic balls of about 25 mm. [0035]
The round shape of magnetic elements of the filter according to the present invention has a number of fundamental advantages in comparison to the bar-like and other non-round shape magnets of the prior art. In particular, it allows for: [0036]
A. Higher field strength. The ability of a permanent magnet in a fluid filter to attract magnetic particles from the liquid is directly related to strength of the magnetic field exposed to the liquid. The magnetic field emanating from a permanent magnet declines exponentially with increased distance from the surface of a magnet. Comparing two different sized permanent magnets made with material having the same magnetic performance, the larger magnet will have a magnetic field that will have more “reach”, or influence at a greater distance, but the field strength at the surface of both magnets is the same. It is also known that the magnetic strength declines from being maximum on the surface of the magnet to much lower values in reverse proportion to the distance from the surface to the third degree. As an example of the rapid nature of the field strength decline, for a spherical anisotropic strontium ferrite permanent magnet (MGO 1), the magnetic field has a strength of 100 H on its surface. At a distance of one radius from the surface, the field strength drops down to only 12.5 H. At a distance equal to a diameter of the ball, that strength drops to only 4 H. Having a large area of the magnetic surface exposed to the flow creates conditions when even small particles are exposed to very high levels of magnetic attraction. In some cases these magnetic forces are greater then the weight and hence inertia of the particle by several orders of magnitude; [0037]
B. Close packing of magnetic elements in the filter with high volume density (up to 70% of volume of working space of the filter); [0038]
C. Tortuous and highly turbulent flow path but without significant hydraulic resistance. As discussed above, the proximity of the magnetic particles in the flowing liquid to the permanent magnet surface inside the filter is very important. In the filter of the present invention, the liquid is forced to come in close proximity to the surface of the magnets. There is no clear or straight path for the liquid to flow. The curved surfaces of the neighboring magnetic balls are such that a flow of liquid through the largest opening between three neighboring spheres leads head-on into the center of the downstream ball. This ensures that after only several layers of magnetic balls passed by the liquid, all of the liquid has been exposed to the high magnetic field strength of the surface of the permanent magnets (given the ratios described above: i.e. distance from the surface relative to the radius of the permanent magnet). Even though the size of the magnetic balls may be small, the field strength on their surface is as great as for large permanent magnets of the same material; [0039]
D. Excellent particle retention. A common drawback of other filter designs using permanent magnet bars or discs (the commonly manufactured shape of low-cost ceramic magnets) is that magnetically attracted particles accumulate on their surface as clumps preferentially on a part of the magnet. These clumps tend to be pulled off by the flow, partly because of the smooth surface of a bar or disc shape. This also happens because as a clump becomes bigger, its outer edge is further away from the surface of the permanent magnet, where the magnetic strength is reduced and it is easier for the flow to pull clumps off. Liquid flowing through a filter body tightly packed with permanent magnet balls will form a tortuous path through the balls. Naturally, the different spaces between the balls have varying levels of velocity and turbulence. Magnetic particles that are attracted to the surface of the magnetic balls will move along the surface to where there is less flow velocity and where the magnetic field is greatest. The contact point between two magnetic balls is an excellent place for accumulated clumps to be securely retained, for two reasons. First, the poles of magnetic balls line up with each other (north pole to south pole) forming a magnetic system of many magnetic balls, and therefore this is where the strongest magnetic field of the magnetic ball is generated. Secondly, the contact point between two balls is where the flow velocity will tend to be the lowest, given its greater flow resistance, and this lower velocity level is contributing to the accumulation of particles in this area. The retained magnetic particles form a meniscus-like shape at this contact point. Experimental data with an oil filter for an automobile indicates that retained particles may account for up to 70% of the void area between the balls before cleaning or replacement are necessary; [0040]
E. High magnetic strength. In combination, a plurality of magnetic balls form a magnetic system with higher individual gradients of magnetic field, than magnets of other forms, arising from the nature of magnetic interaction between the neighboring magnetic balls; [0041]
F. Reasonable cost. In simple, industrial type filters no special stacking or orientation of magnetic elements is required; [0042]
G. Easy handling. Magnetic balls can be magnetized after assembly of the filter by an external magnetic field (electromagnet, solenoid); and finally [0043]
H. Design flexibility. The filter of the present invention is quite flexible in its design and allows for a great number of variations. One example is to create within the filter a number of individual layers of magnetic elements each with the given individual direction of a magnetic field. Another example is a filter with alternation of such layers having an opposite direction of a magnetic field for the most favorable conditions for extraction of filtered particles from a passing by liquid. A further example of a filter design with good performance is to magnetically orient several layers of permanent magnet balls in one direction (perpendicular to the direction of fluid flow), followed by several layers of permanent magnet balls magnetically oriented in the opposite direction. This guarantees exposure to strong reversing magnetic orientation, or magnetic gradient throughout the filter body. [0044]
In addition to the filtration of magnetic particles from a liquid, the magnetic treatment of a liquid has been demonstrated to have a number of (sometimes unexplained) results: [0045]
it lowers viscosity of liquid and allows fluid to more easily pass through porous filter elements; [0046]
it improves atomization of fuels and dispersion of liquid into smaller droplets. Some postulate that by aligning the molecules based on their dipole orientation, the forces of molecular attraction are reduced, thereby improving dispersion; [0047]
it inhibits paraffin's tendency to come out of solution and form solids as the temperature declines to a critical level. It is believed that by aligning the paraffin molecules by their dipole orientation, the paraffin molecules resist linking with each other to form chains, the process of solidification. Applications would include that with diesel fuel systems and downhole in oil production tubing; [0048]
it inhibits the growth of bacteria in diesel fuel tanks having a layer of water on the bottom. Several companies sell products that magnetically treat diesel fuel to prevent the growth of anaerobic bacteria living at the diesel fuel—water interface, whose excrement or waste material forms solids that clog the diesel fuel filters; [0049]
it prevents the formation of scale on the walls of pipes. Scale is the solidification of salts, and such salts become ionic when in solution. Magnetically treating water is said to align the ions by magnetic orientation, and therefore prevent their accumulation on the walls of the pipe. Companies sell such products for plumbing for homes and commercial establishments. Applications of the filter of the present invention may include those used in oil well production tubing as well; [0050]
magnetically treated water used for irrigating plants has shown in some studies to improve the growth of plants, increase the ultimate yield and reduce the amount of water needed by the plant. It is believed by some that such water promotes the increase in the production of aromatics (smell) in flowers. It is postulated also that the lower viscosity of the water lowers the surface tension and improved the absorption of the water into the plant; and finally [0051]
magnetically treated water improves the strength of concrete, ceramics, brick and other foundry products. [0052]
The filter of the invention can be advantageously used in these and other applications where magnetic filtering or treatment is needed. [0053]
In such cases where it is necessary to reduce the effect of magnetic field on the surrounding devices, such as in some automotive applications where the electronic components of the vehicle are mixed with the parts of the hydraulic and fuel supply systems, it is proposed to make the interior of the filter housing round and pack the magnetic balls tightly and in such a way that a full circular uninterrupted line of magnetic balls is formed on the interior periphery of the filter housing. Neighboring magnetic balls would contain the individual magnetic fields of each other so as to form a combined circular magnetic field concentrated predominantly on the inside of the circle. Of course, the use of soft magnetic material for the housing is also helpful in that case to prevent leakage of magnetic field outside the device. [0054]
Another possible configuration of the filter of the invention utilizes the alternating direction of the magnetic field. Magnetic balls of the filter are magnetized in steps forming a plurality of adjacent layers. Magnetization is conducted in such a way that the orientation of magnetic poles of all magnetic balls in a particular layer is the same. At the same time, this orientation being perpendicular to the corresponding orientation of the next layer. In that case, the liquid flows through the number of successive layers of alternating direction of magnetic force. [0055]
Although the present invention has been described with respect to a specific embodiment and application, it is not limited thereto. Numerous variations and modifications readily will be appreciated by those skilled in the art. One example is a reversal of flow in the filter. Another one is to form a circle of magnets on the periphery of the filter so that all internal magnets when magnetized across the direction of the flow would form a combined circular magnetic field having concentric nature of progressively smaller diameter magnetic lines. These and other examples are all intended to be included within the scope of the present invention, which is recited in the following claims. [0056]

Claims

What I claim is:

1. A magnetic filter for purifying and treating a liquid with a magnetic field, said filter comprising:

a filter housing with an inlet and an outlet; and

a plurality of permanent magnetic balls of generally round shape, said magnetic balls contained in said housing,

whereby said permanent magnetic balls being adapted to expose said liquid to said magnetic field as said liquid flows through said filter.

2. The filter as in

claim 1

, wherein said permanent magnetic balls being tightly packed.

3. The filter as in

claim 1

, wherein the orientation of magnetic poles of all of said permanent magnetic balls being in the same direction.

4. The filter as in

claim 3

, wherein said liquid flows through said filter in a direction from said inlet to said outlet, and the direction of said orientation of magnetic poles being perpendicular to the direction of said liquid flow through said filter.

5. The filter as in

claim 1

, where said magnetic balls forming a plurality of adjacent layers, the orientation of magnetic poles of all magnetic balls in a particular layer is the same, said orientation being perpendicular to the corresponding orientation of the next layer.

6. The filter as in

claim 1

, wherein said permanent magnetic balls being made from a magnetic material selected from the group consisting of Strontium ferrite, Barium ferrite, Samarium Cobalt, Nd-Fe-B, and Nd-Fe-B-Co.

7. The filter as in

claim 1

, wherein said permanent magnetic balls all having a first diameter.

8. The filter as in

claim 7

, further comprising a second plurality of permanent magnetic balls, said balls all having a second diameter, said balls placed between the magnetic balls having said first diameter, said second diameter being smaller than said first diameter.

9. The filter as in

claim 8

, wherein said second diameter being about 0.15 of said first diameter.

10. The filter as in

claim 8

, wherein said second plurality magnetic balls made of a soft magnetic material.

11. The filter as in

claim 1

, wherein said permanent magnetic balls having a diameter being in the range between about 2 to about 20 mm.

12. The filter as in

claim 1

, wherein said permanent magnetic balls having a diameter being in the range between about 4 to about 7 mm.

13. The filter as in

claim 1

, wherein said filter housing made of soft magnetic material.

14. The filter as in

claim 13

, wherein said soft magnetic material being steel.

15. The filter as in

claim 1

, wherein said housing having a round interior, said magnetic balls being tightly packed against said round interior forming complete uninterrupted circular lines, whereby any leakage of said magnetic field is substantially reduced.

16. A method for treating a liquid with a magnetic field, said method including a step of passing said liquid through a filter comprising a housing and a plurality of permanent magnetic balls of generally round shape, said magnetic balls contained in said housing, said permanent magnetic balls adapted to expose said liquid to said magnetic field as said liquid flows through said filter.

17. A method of removal and retention of magnetic particles from a liquid, said method including a step of passing said liquid through a magnetic filter comprising a filter housing, and a plurality of permanent magnetic balls of generally round shape, said magnetic balls contained in said housing, said permanent magnetic balls adapted to expose said liquid to said magnetic field as said liquid flows through said filter, said permanent magnetic balls also adapted to retain said magnetic particles thereon.