Patent Publication Number: US-2012031738-A1

Title: Magnetic assembly for loading and conveying ferrous metal articles

Description:
FIELD OF THE INVENTION 
     This invention relates to combinations of mechanical belt conveyors and magnetic rolls and pulleys. More particularly, this invention relates to combinations of such machinery for automatically loading and conveying ferrous articles such as scrap steel and small steel parts. 
     BACKGROUND OF THE INVENTION 
     Turn back pulleys or rollers of powered continuous loop belt conveyors are known to be specially adapted to include embedded or internally housed permanent magnets. Where such turn back rollers or pulleys are so adapted, they advantageously cause the continuous loop conveyor to additionally perform an automatic ferrous metal attracting and loading function. Where, for example, such a magnetically adapted conveyor pulley is positioned over a moving stream of materials (or a relatively moving stream of materials resulting from movement of the conveyor assembly) ferrous metal parts and/or scrap steel contained within the stream are advantageously drawn out of such stream and into a magnetically attached and contacting relationship with the conveyor belt at points radially overlying the magnetic pulley. The continuously looping motion of the conveyor belt over the magnetic pulley draws the ferrous metal parts or scrap steel along the conveyor and away from the magnetic pulley for conveyance along the conveyor belt to a desired remote location for disposal or separate storage. 
     A common drawback or deficiency of such magnetic conveyor pulley and conveyor belt combinations is an insufficiency or deficit in the magnetic strength and density of lines of magnetic flux which extend from the pulley at the conveyor&#39;s end. As a result of such deficiency, such common magnetic pulley and conveyor combinations have only a limited capability to attract and convey away ferrous magnetic parts and scrap materials. 
     Such magnetic attraction deficit commonly results from an adoption of an intuitive mechanical arrangement of the polar axes of the permanent magnets which are contained within or supported by the magnetic conveyor pulley. Just as the lateral cross-sectional shape of a conveyor pulley is circular, commonly known magnetic adaptations of conveyor pulleys have arranged the polar axes of the contained or supported permanent magnets to emanate magnetic flux outwardly in a substantially circular radial array. Such radial arrays of magnetic flux are known to result from either one of two commonly known modes of mounting of permanent magnets within or upon a continuous loop conveyor&#39;s pulley. In one such mode, the permanent magnets are arranged in multiple N,N,S,S,N,N . . . polar orientation chains, each such magnet chain extending parallel with the pulley&#39;s rotation axis and such magnet chains being arranged circumferentially about the pulley&#39;s annular outer periphery. In the other mode, U-shaped or horseshoe magnets which present their north and south poles at paired distal ends of the magnet&#39;s arms are similarly arranged in a radial array about the pulley. Where such U-shaped magnet configuration is utilized, a paramagnetic axle core within the pulley is often utilized as a magnetic armature for completing the “U” configuration of such north and south magnet arm pairs. Both modes of conveyor pulley magnet adaptation described above produce a circumferential array and extension of lines of magnetic flux, and in both the resultant magnetic flux is undesirably weak in all radial directions. 
     The instant inventive assembly for loading and conveying ferrous metal articles solves or ameliorates problems and deficiencies discussed above by configuring the magnetically adapted conveyor pulley to be or function as a substantially single magnet having a north/south polar axis which intersects the pulley&#39;s axis of rotation at a perpendicular or substantially 90° angle, and which crosses the entire lateral cross-sectional diameter of the pulley. 
     BRIEF SUMMARY OF THE INVENTION 
     A first structural component of the instant inventive assembly for loading and conveying ferrous metal articles comprises a magnet having a north pole, a south pole, and a rotation axis extending between the north pole and the south pole, the north and south poles being configured as or forming an annular belt supporting surface. In a preferred embodiment, such annular belt supporting surface is continuously circumferential and has a circular lateral cross-sectional shape. 
     A further structural component of the instant inventive assembly comprises a continuous loop conveyor belt which extends over and frictionally contacts the magnet&#39;s arcuately curved north and south poles. 
     A further structural component of the instant inventive assembly comprises means for rotating the magnet about its rotation axis. Such rotation means may comprise the conveyor belt where the magnet functions as a conveyor belt supporting idler pulley. Alternatively, such means may comprise drive axle structures and assemblies which may couple with a motor driven rotary power source such as an electric motor. 
     By configuring the conveyor or pulley component of the instant inventive assembly as a permanent magnet having opposing curved conveyor belt supporting north and south poles, magnetic flux (i.e., the magnetic field characteristic imposed by a permanent magnet upon a physical space or volume) emanating from pulley/magnet is augmented and strengthened along the full diameter of the pulley/magnet, resulting in overall enhanced magnetic strength. 
     In use of the inventive assembly, streams of ferrous article containing materials passing beneath the assembly are advantageously exposed to the rotating magnetic field emanating from the conveyor&#39;s pulley/magnet. As a result, ferrous scrap metal or parts within the stream are attracted and drawn from the stream into contact with the conveyor for carriage to a remote location for disposal or separate storage. 
     Accordingly, it is an object of the instant invention to provide an assembly for loading and conveying ferrous metal articles which provides structures, as described above, and which arranges those structures in relation to each other, as described above, for the performance of beneficial functions, as described above. 
     Other and further objects, benefits, and advantages of the present invention will become known to those skilled in the art upon review of the Detailed Description which follows, and upon review of the appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partial perspective view of the instant inventive assembly. 
         FIG. 2  redepicts  FIG. 1 , the view of  FIG. 2  showing a conveyor belt component of the assembly removed, the view exclusively showing the magnet component of the assembly. 
         FIG. 2A  redepicts  FIG. 2 , the  FIG. 2A  showing an alternative magnet axle assembly. 
         FIG. 3  redepicts  FIG. 2 , the view of  FIG. 3  showing sheath and sub-magnet polar axis segments of the magnet removed. 
         FIG. 4  alternatively redepicts  FIG. 2 , the view of  FIG. 4  showing the sheath polar axis segment of the magnet removed. 
         FIG. 5  is a sectional view as indicated in  FIG. 2 . 
         FIG. 6  is a magnified view of a portion of the structure depicted in  FIG. 5 , as indicated in  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
     Referring now to the drawings, and in particular to Drawing  FIGS. 1 and 2 , a preferred embodiment of the instant inventive assembly for loading and conveying ferrous metal articles is referred to generally by Reference Arrow  1 . A major structural component of the assembly  1  comprises a permanent magnet which is referred to generally by Reference Arrow  6 . The magnet  6  dually functions as a conveyor pulley having a rotation axis  11  and as means for attracting ferrous metal articles  3 . In a preferred embodiment, referring further simultaneously to  FIGS. 3 and 5 , an axle shaft receiving sleeve  8  is aligned concentrically about and along the rotation axis  11 , such sleeve  8  forming an axle shaft receiving bore  10 . To facilitate transmission of rotary power from an axle shaft (not depicted within views) received within bore  10 , a key slot  12  is provided. Alternatively, referring further simultaneously to  FIG. 2A , an alternatively configured magnet component  6 A presents journal axles  10 A having rotation keys  12 A. The axle shaft  10  and key slot  12  (or the journal axle  10 A and key  12 A, as the case may be) constitute means for rotating the magnet  6  or  6 A about the rotation axis  11 . Where such means are provided, motor means such as an electric motor drive (not depicted within views) coupled to the axle assembly is preferably further provided for rotatably moving the magnet  6  or  6 A. Alternatively, in situations where the magnet  6  or  6 A functions as a conveyor belt idler pulley, a provided conveyor belt  2  suitably functions as the means for rotating the magnet  6  or  6 A about the rotation axis  11 . Where such alternate rotating means are provided, such means preferably further provides an electric motor powered drive pulley at an opposite discharge end of the assembly  1 . In such drive configuration, friction between the inner surfaces  4  of the continuous loop conveyor belt  2  and the circumferential outer surface  22  of the pulley  6  rotatably moves the pulley  6  upon the continuously looping motion of the conveyor belt  2 . 
     Referring simultaneously to  FIGS. 2-5 , the magnet  6  preferably has a polar axis  27  which spans the lateral cross-sectional diameter of the magnet, and which substantially perpendicularly intersects the rotation axis  11 . In a preferred embodiment, the magnet  6  is multiply segmented along the polar axis  27 . A first polar axis segment of the magnet  6  preferably comprises a mounting plate  14 , 16 . In a preferred embodiment, the mounting plate  14 , 16  is fixedly attached to or is wholly formed with the axle sleeve  8 , and the mounting plate  14 , 16  preferably comprises paramagnetic or “mild” steel. Suitably, the mounting plate magnet segment  14 , 16  may alternatively comprise a non-paramagnetic metal such as stainless steel, brass, or aluminum. 
     Further polar axis segments of the magnet  6  preferably comprise pluralities or multiplicities of stacked sub-magnets  26  and  28  which respectively overlie and underlie the plate magnet segment  14 , 16 . Each of the sub-magnet segments  26  or  28  preferably comprises a permanent magnet which is situated with respect to the magnet  6  so that its north/south polar axis aligns with and is substantially parallel to the magnet&#39;s polar axis  27 . 
     Referring further simultaneously to  FIGS. 2-5 , a further polar axis segment of the magnet  6  preferably comprises a cylindrical sheath  21 N, 21 S. The annular and circumferential outer surface  22  of the magnet&#39;s sheath segments  22 N, 22 S preferably forms and functions as a circular cylindrical conveyor belt supporting surface. In a preferred embodiment, the magnet&#39;s polar axis sheath segments  21 N, 21 S comprise a durable non-paramagnetic material such as non-magnetic stainless steel, brass, or aluminum. The non-paramagnetic character of the sheath segments  21 N, 21 S advantageously allows lines of magnetic flux  33  emanating from the sub-magnet segments  26  and  28  to “transparently” pass through the magnet&#39;s sheath segments  21 N, 21 S rather than undesirably armaturing the north and south poles of peripherally positioned sub-magnet segments  26  or  28 . 
     Referring simultaneously to  FIGS. 1-5 , magnet end caps  18  and  20  are preferably provided, such caps preferably being fixedly attached to opposite axial ends of the axle sleeve  8 , the mounting plate segment  14 , 16 , and the sheath segment  21 N, 21 S. Upon such attachment and mounting of the end plates  18  and  20 , they advantageously hermetically close the magnet&#39;s semi-cylindrical void spaces  23 , 24  which house the magnet&#39;s permanent magnet sub-segments  26  and  28 . 
     Referring simultaneously to  FIGS. 5 and 6 , structural integrity of the magnet  6  in addition to that provided by the end caps  18  and  20  is provided by a deposition of a durable adhesive  30  over the surfaces of the magnet&#39;s sub-segments  26  and  28  and over the opposing surfaces of the mounting plate  14 , 16 . In a preferred embodiment, the adhesive  30  comprises a cyanoacrylate based glue. 
     Referring simultaneously to  FIGS. 1 ,  2 ,  4 , and  5 , the segmenting of the conveyor pulley/magnet  6  along the magnetic polar axis  27  facilitates a strengthening and augmentation of lines of magnetic flux  33  extending across the full diameter of the magnet  6 . The magnetic flux lines  33 , as drawn in  FIG. 5 , are representative of similar lines emanating from the complete semi-circular north half  21 N of the magnet  6 , and entering the complete semi-circular south half  21 S of the magnet  6 . As a result of such magnetic flux augmentation, ferrous magnetic articles  3  may be magnetically attracted from a relatively long distance and may be carried away upon the outer surface  7  of the conveyor belt  2  for separate disposal or separate storage. 
     While the principles of the invention have been made clear in the above illustrative embodiment, those skilled in the art may make modifications in the structure, arrangement, portions and components of the invention without departing from those principles. Accordingly, it is intended that the description and drawings be interpreted as illustrative and not in the limiting sense, and that the invention be given a scope commensurate with the appended claims.