US3377651A

US3377651A - Apparatus for making magnetic material

Info

Publication number: US3377651A
Application number: US411454A
Authority: US
Inventors: James R Ireland
Original assignee: Individual
Current assignee: IG TECHNOLOGIES Inc A CORP OF
Priority date: 1964-11-16
Filing date: 1964-11-16
Publication date: 1968-04-16
Anticipated expiration: 1985-04-16
Also published as: GB1059808A

Description

April 16, 1968 -J. R. IRELAND APPARATUS FOR MAKING MAGNETIC MATERIAL Filed Nov. 16, 1964 M T 1 I l INVENTOR. JAMES E /e-4A/0 United States Patent 3,377,651 APPARATUS FOR MAKING MAGNETIC MATERIAL James R. Ireland, RR. 2, Smoke Road, Valparaiso, Ind. 46383 Filed Nov. 16, 1964, Ser. No. 411,454 Claims. (Cl. 18-1) ABSTRACT OF THE DISCLOSURE Ferrite crystals and crystal fragments are removed from a slurry containing crystals, crystal fragments and fluid by feeding said slurry upwardly into a nip region formed between a pair of magnetic rollers or pulleys having parallel axes. Conveyors passing around the magnetic rollers convey the magnetic material attracted to the rollers or pulleys through the nip region wherein the magnetic material is magnetically oriented. The conveyors then convey said material away from the nip region for further processing.

This invention relates to an apparatus for removing ferrite crystals and crystal fragments from a slurry containing crystals, crystal fragments and fluid and subsequently magnetically orientating the ferrite crystals and crystal fragments to form a desired grade of magnetic granule.

In the process of manufacturing certain ceramic magnetic grades, such as indicated empirically by MO-nFe O of which BaO-6Fe O and PbO-6Fe O are specific examples, it is desired to produce granules of predetermined size consisting of a multitude of hexagonal ferrite crystals or crystal fragments. Furthermore, it is desired that each ceramic magnetic granule have all the crystals associated therewith magnetically aligned in parallel relation to each other.

One well known method of producing ceramic magnetic granules is to place a slurry, consisting of crystals, crystal fragments and water, into a form in which there exists a magnetic field of suflicient intensity to magnetically orient the crystals in parallel fashion. After magnetically orienting the crystals, the slurry is then pressed to remove the water content while retaining the ceramic magnetic material in the form. The resulting ceramic compound may then be broken up into granules of the desired size.

The foregoing method of producing ceramic magnetic granules is expensive and time consuming since it requires a suitable press and press operator, and the pressing operation itself is inherently slow. To further increase the expense of the foregoing method, a sufiicient number of forms are required so that continuous production of ceramic magnetic granules can be had.

It is therefore an important object of the present invention to provide means for simultaneously removing a substantial quantity of water associated with ferrite crystals in a slurry and magnetically orienting the crystals which form magnetic granules.

Another object of the present invention is to provide a pair of magnetic pulleys for removing ferrite crystals and crystal fragments from a slurry.

Still another object of the present invention is to provide means for quickly removing a substantial quantity of water from a slurry while leaving a small quantity of water behind which can be quickly removed by drying heat.

A further object, and one of considerable importance from a commercial standpoint, resides in the provision of a continuous means for removing crystals and crystal fragments from a slurry which is completely automatic and does not require a full-time operator.

3,377,651 Patented Apr. 16, 1968 Yet another object of the present invention is to provide means for magnetically orienting ferrite crystals and crystal fragments as they pass through a magnetic pulley assembly.

Further objects of this invention as well as a better understanding thereof, may be had from the following description when considered in conjunction with the accompanying drawings in which:

FIGURE 1 is a side elevational view of a preferred apparatus in accordance with the present invention for removing crystals and crystal fragments from a slurry; and

FIGURE 2 is a top plan view of the apparatus shown in FIGURE 1, showing an alternative means for driving said apparatus.

The apparatus shown in FIGURE 1 is generally designated by reference numeral 10 and has particular utility when used to remove magnetic particles from a slurry containing, by way of example, ferrite crystals, crystal fragments and water. However, it will be understood that the apparatus 10 can be used to remove any magnetic particle from a compound of magnetic and non-magnetic particles.

A pair of magnetic rollers 12 and 13 have their axes in a parallel relation and lying in a common plane. Rollers 16 and 17 have their axes in parallel relation with each other and in parallel relation with magnetic rollers 12 and 13, and lying in the same plane. Wrapped about the magnetic roller 12 and idler roller 16 is a flexible conveyor belt 20, and wrapped about the magnetic roller 13 and driven roller 17 is a flexible conveyor belt 21. A motor 23 is provided with a pulley 24 for transmitting rotational movement to a pulley 25 via belt 26. Roller 17 has an extended shaft portion 28 which has secured thereto pulley 25. The continuously moving contact area between the

conveyor belts

20 and 21 is herein defined as a nip region.

The tension of web 21 between the magnetic roller 13 and the roller 17 is sufficient to cause magnetic roller 13 to rotate as the roller 17 is driven. As shown at 30, the magnetic rollers 12 and 13 have a contacting Zone which provides sufiicient friction to transmit rotating motion from the magnetic roller 13 to magnetic roller 12, and therefrom via the conveyor belt 20 to idler roller 16.

In operation, the slurry designated by reference numeral 32 is fed to the input side of the contacting zone 30 by slurry feeding means 33. Since the rollers 12 and 13 and Conveyor belt 23 and 21 are rotating in the direction as indicated at 35, the slurry 32 will be drawn through the contacting Zone 30 to the output thereof. This action will cause a substantial quantity of water to fall away by gravitational force while the magnetic particles are drawn toward the magnetic pulley at the contacting zone 30. A further substantial quantity of water is removed from the slurry 32 by a wringcr or pressing action between the contacting surfaces of

conveyor belts

20 and 21 allowing the magnetic particles to pass through the contacting Zone 30 in a substantially dry state. Magnetic particles which have been extracted from slurry 32 will continue to adhere to

conveyor belt

20 or 21 because of the magnetic field imposed therethrough by magnetic rollers 12 and 13. As the particles which adhere to conveyor belt 26 and move thereupon past a point indicated at 34, the magnetic attraction of magnetic roller 12 is removed. The particles on conveyor belt 20 are then passed under a suitable heater 36 for removing any water which may still be associated therewith. A scraper 38 shown in FIG- URE 1 is provided to remove the magnetic particles from the conveyor belt 20 thereby producing the desired ceramic magnetic granules.

In a similar manner, as the particles which adhere to conveyor belt 21 move thereupon past a point indicated at 40, the magnetic attraction of magnetic roller 13 is removed. The particles on conveyor belt 21 are then passed under a suitable heater 41 for removing any water which may still be associated therewith. A scraper 42 shown in FIGURE 1 is provided to remove the magnetic particles from conveyor belt 21 thereby producing the desired ceramic magnetic granules.

As shown in FIGURES 1 and 2, magnetic roller 12 and idler roller 16 are mounted between a pair of

supports

45 and 46 while magnetic roller 13 and roller 17 are mounted between a pair of supports 47 and 4 8. Provided in

supports

45 and 46 are slots 56* and 51 for receiving end shaft portions 53 and 54 which are journaled in bearing support caps 55 and 56 respectively. Also provided in

supports

45 and 46 are

slots

58 and 59 for receiving end shaft portions 61 and 62 which are journaled by movable bearings 64 and 65 respectively. Movable bearing 64 is arranged for a slidable adjustment in a slot 66 which, in turn, is machined in an end support 67. Screws 68 may be provided to secure the end support 67 to support 45. Secured to the movable bearing 64 is a threaded shaft 70 which, in turn, passes through a bracket 71. An adjusting nut 72 is threaded on the shaft 70 and extends beyond the bracket 71, while a locking nut 73 is threaded on the shaft 70 behind the bracket 71. In a similar fashion, movable bearing 65 is slidably adjustable in a slot 76 which slot is machined in an end support 77. Connected to movable bearing 65 is a threaded shaft 79 the free end of which passes through a bracket 80. Threaded on the shaft 79 is an adjusting nut 82 which extends beyond the bracket 80, while also threaded on the shaft 79 is a locking nut 83 which is behind the bracket 80.

To adjust the tightness of conveyor belt 20, the end shaft portions 61 and 62 of idler roller 16 are moved in the

slots

58 and 59 by applying tension to movable bearings 64 and 65. This is accomplished by turning nuts 72 and 82 on shafts 70 and 79 respectively to bring the idler roller 16 toward the brackets 71 and 80.

Magnetic roller 13 and driven roller 17 are secured in substantially the same manner as magnetic roller 12 and idler roller 16 and have substantially the same means of adjustment for conveyor belt 21.

Supports

45, 46, 4'7 and 48 are secured to a base by screws or by a suitable welding operation. A motor mounting block 83 is secured to the base 85 by fasteners 89 and 90. Motor 23 is then secured to motor mounting block 88 by fasteners 92 and 93.

The rollers 12 and 13 are constructed and arranged by placing axially magnetized permanent magnet disks 95 of annular configuration and steel pole piece disks 96 of annular configuration alternately on a shaft portion 97, and securing the magnets 95 and pole pieces 96 in place by a pair of

end plates

100 and 101. The magnets 95 may be lesser diameter than the pole pieces 96 thereby providing recessed portions 102 which may be filled with a non-magnetic material such as epoxy. The magnets 95 on either side of each of the pole pieces 96 are arranged so that a pole surface of each of the magnets is in contact with the flat surface at the adjoining side of the pole piece 96. The permanent magnets alternate in polarity along the shaft so that the pole pieces 96 are of alternate polarity as indicated in FIGURE 2.

As shown in FIGURE 2, the magnets 95 may be alternated with the pole pieces 96 over the entire length of the roller 12 to provide a sufliciently large surface to act as a magnetic pulley. The alternate north and south poles along the axis of roller 12 are constructed and arranged so that as the rollers 12 and 13 rotate as indicated at 35, FIGURE 1, each magnetic pole piece of roller 12 will be opposed at the contact zone 30 by a magnetic pole piece of opposite polarity of the roller 13. However, it may be desired to mechanically synchronize the rollers 12 and 13 by applying rotating motion thereto from a motor through a synchronized gear train 111, as shown in FIG- URE 2.

Summary of operation A pair of magnetic rollers 12 and 13 are rotated in a direction 35 as shown in FIGURE 1. Wrapped about rollers 12 and 13 and rotated therewith are

conveyor belts

20 and 21 respectively. As a slurry 32, consisting of ferrite crystals, crystal fragments and water, is applied to an input side of a contacting zone 30, which exists between the

conveyor belts

20 and 21, the ferrite crystals are attracted toward the contacting zone 30 by a magnetic field afforded therebetween by magnetic rollers 12 and 13. In so attracting the ferrite crystals upward toward the contacting zone 30, a substantial quantity of water associated with the slurry 32 will fall away due to gravitational force, while a still further substantial quantity of water will be removed as the slurry passes through the contacting zone 30 and is subjected to a wringing or squeezing action. The ferrite crystals which are attracted toward the contacting zone 30 are magnetically oriented in parallel fashion to each other to form magnetic particles which continue to adhere to

conveyor belts

20 and 21 due to the magnetic fields of rollers 12 and 13. After the magnetic particles are conveyed past a predetermined point on each

conveyor belt

20 and 21, heat is applied thereto to remove any water which may still be associated with the magnetic particles. As the magnetic particles are conveyed further by conveyor belts 2t) and 21, they are removed therefrom by

scrapers

38 and 42 respectively to producing the desired ceramic magnetic granules.

Although the description has been given with respect to a particular embodiment, it is not to be construed in a limiting sense. As mentioned hereinabove, both rollers 12 and 13 are magnetic and of similar constrction; however, either roller 12 or 13 may be replaced by a nonmagnetic roller or by a demagnetized ferrous roller. The foregoing description of this invention concerns only the preferred embodiment thereof, and accordingly, changes and modifications may be made therein by those skilled in the art without departing from the spirit and scope of the novel concepts of this invention.

I claim as my invention:

1. Apparatus for treating magnetic material in a slurry comprising,

a pair of substantially horizontally disposed rollers mounted for rotation on substantially parallel axes, conveyor means for movement along an arcuate conveyor path about the axis of one of the rollers, the arcuate conveyor path extending between said rollers with the conveyor moving in an upward direction along said arcuate conveyor path,

said rollers providing a nip region along said arcuate conveyor path with an input region in advance of and below said nip region and an output region beyond and above said nip region along the arcuate conveyor path, and

slurry feeding means for directing said slurry into said input region, and

means for tending to hold magnetic material against said conveyor means for passage through said nip region while accommodating removal of liquid by gravity and by a squeezing action of said rollers at said nip region.

2. A system for treating magnetic material in a slurry comprising,

a pair of substantially horizontally disposed magnetic pulleys mounted for rotation on substantially parallel axes and providing a nip region therebetween, the pulleys providing a magnetic field in the direction between the pulleys and through the nip region,

conveyor means extending about the peripheries of respective pulleys and travelling in an upward direction at said nip region therebetween, and

means for supplying the slurry as an upwardly directed stream impinging on the conveyor means at the lower side of said nip region with the pulleys serving to attract magnetic material of the slurry to the conveyor 5 6 means for movement through the nip region while 4. The system of claim 3 with the magnetic rollers havliquid is squeezed therefrom at the nip region. ing annular pole faces of opposite magnetic polarity dis- 3. A system for treating magnetic material in a slurry posed in confronting relation at opposite sides of said comprising, nip region to provide a magnetic field in the direction a pair of magnetic rollers having parallel axes and de- 5 through said nip region.

fining a nip region therebetween, 5. The system of claim 3 with means for synchronizing a pair of idler rollers having axes parallel to the axes of the rotation of said magnetic rollers so that said conveyors the magnetic rollers, travel at the same surface speed at said nip region. a first continuous web wrapped about one of said magnetic rollers and one of said idler rollers to provide a References Cited first coinveyotr, b d b t th th 10 UNITED STATES PATENTS a secon con muons we wrappe a on e 0 er of said magnetic rollers and the other of said idler 3 2 12/1959 Fnts ch XR rollers to provide a second conveyor, 6/1962 4 drive means for rotating said magnetic rollers and said 15 2,095,262 6/1963 Malsh et 18 9 XR idler rollers to move said conveyors in an upward di- 3317361 11/1965 Ryan et rection through said nip region, and 3,228,052 1/ 1966 Claus slurry feeding means for applying the slurry to said conveyors at the region below said nip region for attrac- FOREIGN PATENTS tion of magnetic material in the slurry to the con- 20 519,576 3/1931 Germany. veyors and movement through said nip region While liquid of the slurry is squeezed from the magnetic WILLIAM J. STEPHENSON, Primary Examiner. material at the nip region.