US 3329350 A
Description (OCR text may contain errors)
July 4, 196.7 R. K. wlsGx-:RHOF ETAL 3,329,350
PULVERIS ING APPARATUS 2 Sheets-Sheet Filed May 25. 1964 INVENTOR RAYMOND K. WISGERHOF N LYS A. CHR
ISTIANSEN United States Patent O 3,329,350 PULVERISING APPARATUS Raymond K. Wisgerhof and Nils A. Christiansen, Golden, Colo., assiguors, by mesne assignments, to Otis Gay and Harry Anderson, both of Everett, Wash.
Filed May 25, 1964, Ser. No. 369,820 11 Claims. (Cl. 241-38) This invention relates to new and useful pulverizing apparatus, and more particularly to apparatus which is specifically adaptable for use in pulverizing rock, especially mineral ores, into line particles of predetermined sizes. The apparatus is further characterized by providing within a unitary housing structure the means necessary for simultaneous or successive pulverizing and treatment of materials introduced therein.
The principal object of the present invention is to provide for a new and useful apparatus capable of pulverizing various substances in a rapid and efficient manner, and to provide in such apparatus either for the combined or successive pulverization and treatment of substances.
Another object of the present invention is to provide a novel and improved method and means for the multistage, high-speed wet or dry crushing and pulverizing of materials and particularly mineral ores, such as, for example, ores of gold, iron, copper, oil shale, or molybdenum into uniformly small, finely divided particles.
It is another object of the present invention to provide in an apparatus of the character described for the novel disposition and arrangement of a series of blade elements disposed between a pair of inner and outer concentric rotating members for the purpose of pulverizing materials by the combined action of cutting and impact under extremely high effective speeds, and in such a way as to break down and pulverize mineral ores and other substances into sharp broken grains.
It is a still further object of the present invention to provide in a pulverizing apparatus for independently rotatable rotor and housing members cooperating to grind and pulverize materials in a succession of stages to increasingly reduce sizes while controlling the advancement of the materials between successive stages according to size; and furthermore, to carry out grinding and pulverization of the materials in each stage under the combined action of cutting and impact.
In accordance with the present invention, a preferred embodiment thereof takes the form of a rotor concentrically mounted within a housing, the housing having a series of circumferentially extending blade elements positioned in predetermined spaced relation along its inner surface and the rotor having a series of axially spaced generally radially extending blade elements arranged transversely to the blades in the housing for rotation through the clearance area formed between the housing blades so that under relative rotation between the rotor and housing the materials introduced into the housing will be finely ground by the cooperative action of the blade elements. Moreover, the rotor and housing members are most desirably mounted for independent rotation so that the members may be rotated in the same or opposite directions to impart the desired speed and direction of movement to the materials. In the construction of the rotor, it is most desirably divided into a series of stages whereby the material is advanced according to size between stages, then ground to a progressively reduced size for subsequent advancement to the next following stage and in this way he capable of controlling the advancement of materials through the apparatus according to size.
In addition, the particular construction and arrange- "ice ment of the rotor and housing members permits of combined pulverization and treatment of materials introduced, as well as wet or dry pulverizing as desired; or the material may be reduced to a predetermined size, then treated as it leaves the apparatus.
The above and other objects, advantages and features of the present invention will become more readily understood and appreciated from a consideration of the following detailed description taken together 'with the accompanying drawings, in which:
FIGURE l is a side elevation, partially in section, of a preferred form of grinding apparatus, certain parts being broken away and illustrated in section, to better show the construction thereof.
FIGURE 2 is a sectional view taken on line 2-2 of FIGURE l; and
FIGURES 3 and 4 are enlarged views of modified forms of blade elements which may be suitably employed in the grinding apparatus of the present invention.
While the present invention is conformable for use, as will be apparent to those skilled in the art, in pulverizing and treating a great number and variety of substances, the preferred embodiment will be described with reference to the pulverization and treatment of mineral ores, the object being to grind and pulverize the ore to an extremely tine mesh size and to the extent that a fine dust or powder of a predetermined size is formed.
In the preferred form, an apparatus 10 is comprised broadly of an outer housing or shell 12 having a materials feed inlet 13 and an outlet hopper or treatment chamber 14. Forming a continuation of the lower end of the outlet hopper is an outlet tube 15 supported within a bearing mount 16, the latter being affixed to an upright support stand 17. A rotor 20 is positioned concentrically within the outer shell 12 and includes an upwardly extending drive shaft 21 journaled within a bearing mount 22 aixed to the upper end of the support stand 17. In this way, the rotor and shell are mounted for independent rotation, and this may be suitably accomplished, for instance, by means of rotor and housing drive motors 24 and 25, respectively. The rotor drive motor 24 operates through power transmission belts 26 trained over a drive pulley 27 on the motor drive shaft and a driven pulley 28 keyed for rotation on the rotor drive shaft 21. Similarly, the housing drive motor 25 operates through power transmission belts 26 extending from a drive pulley 27 to a driven pulley 28', the latter being keyed for rotation on the upper end of the outlet tube 15. Preferably, the drive motors 24 and 25 are reversible so as to be capable of lrotating the rotor and housing in either direction, and for example under counter-rotation has the advantage of establishing high effective speeds of rotation for comparatively low individual speeds of rotation of the rotor or the shell alone. In that the rotor and shell are mounted independently of one another with the loads being carried and transferred entirely through the bearing mounts 16 and 22 into the support stand 17, the bearing mounts and enclosed bearings should be of heavyduty construction and, although not shown, the preferred form may employ opposed sets of self-aligning roller bearings within each bearing mount in order to maintain accurate alignment between the rotor and shell while supporting the members in journaled, aligned relation. In this same relation, although the apparatus is illustrated in vertical disposition, it may be tilted to any desired angle between the vertical and horizontal positions without materially affecting the operation.
The housing or shell 12 is formed to cooperate with the rotor for grinding and pulverizing materials introduced .into the shell through the feed hopper. Accordingly, the shell is of generally cylindrical configuration nd of heavy-walled construction with an annular plate positioned across the upper end thereof to provide a imited central opening 31 for disposition and communiation of the hopper 13 with the interior of the shell. Xs illustrated, the feed hopper has an upper frusto-conial portion 32 and a lower ring-like portion 33 attached o the inner edge of the plate 30. A delivery duct 34 forms tn upward extension from the feed hopper for recepion of materials from an inclined trough represented at i or other suitable means of conveyance for the maerials.
The lower end of the cylindrical shell continues into he outlet hopper 14, which may form a treatment cham- )er for the ground materials in a manner to be described. l`he outlet hopper 14 converges downwardly away from `he shell into the outlet tube 1S which in turn leads into t suitable conduit 38 for delivery of the ground material tway from the outlet side of the apparatus. If desired, a .ource of vacuum may be attached to lower terminal end 59 of the outlet tube 15 beneath the bearing mount to :reate a slight negative pressure from the outlet side of :he chamber, although under normal conditions the rna-V :erials will advance at the proper rate merely under the influence of gravity. v
The inner wall of the sh-ell has a plurality of axially spa-ced circular rows of blade elements 44. In general, each row is comprised of a series of circumferentially extending, arcuate plates directed inwardly in a horizontal direction from the chamber wall at equally spaced intervals. Each blade is permanently attached to the chamber wall, for instance, by welding to the inner surface of the wall or by permanently aftixing each blade within a slot formed within the wall for that purpose. It will be seen also that the uppermost row of blades 44 consists of a number of relatively thick plates, in relation to the thick* ness of the plates in the lower rows, in order to effect preliminary grinding or crushing of the materials introduced into the chamber. The blades in each row are disposed in staggered relation, or out of axial alignment, to the blades in adjacent rows above and below that row, as best seen from FIGURE 2, and in this way the plates will act as baffles in the path of advancement of materials along the inner wall surface of the shell.
The rotor is mounted within the shell for rotation of a series of rotor blade elements 48 through the axial spaces formed between adjacent rows of the blade elements 44, whereby to thoroughly grind and pulverize the materials between the blade elements. The preferred form of rotor is constructed also to form a series of successive stages for reduction of the material to a suiiiciently small size in each stage to pass to the next succeeding stage until at the nal stage the material will have become reduced to finely ground particles within a predetermined size. To this end, the rotor drive shaft 21 is dened by an inner inlet tube 50 and an outer drive sleeve 52 projecting downwardly through the bearing mount 22 and throughout the length of the shell 12. The outer drive sleeve 52 is attached to the inlet tube beneath the upper bearing mount by shear pins 53; and, in connect-ed relation, :the outer drive sleeve and inlet .tube have aligned openings or jets 54 to permit the introduction or spraying 'of water or chemicalsrthrough the inlet tube into the interior of the chamber. In order to divide the chamber into grinding stages, annular disks S5 are attached to the outer drive sleeve 4at spaced, axial intervals therealong to extend outwardly and intermediately between adjacent rows of blade elements 44 on the shell. Preferably, each lower disk in succession is of increased diameter, as seen from FIG- URE 1, .so that the spacing or clearance area between each disk in succession and the chamber wall is reduced, and acccordingly the size of material must be correspondingly reduced for passage through the clearance area to the next stage.
Considering in more detail the disposition and arrangement of the cutter blades 48, each is axially aligned in a plane substantially transverse to the plane of the circumferentially extending blades 44 in the chamber. In the preferred form, the cutter blades 48 are mounted in open, radially extending slots 62 that extend generally in a radial direction inwardly from the outer peripheral edge of the disk at intervals. Each cutter blade is preferably formed of a relatively fiat, thin, rectangular plate that is positioned in the slot to project equally above and below the disk into the axial space or gap formed between adjacent blade rows on the :chamber wall and, as stated, in a direction transverse or normal to that of the blade elements 44. As a result, particles thrown outwardly by centrifugal force will collide with the rotor blades; whereas, particles advancing axially between stages will collide with the blades 44 in the housing. Furthermore, it can be theorized that the rotor and housing blades cooperate to entrap the material therebetween to impart a more positive cutting or grinding action to the material, and this is evidenced by the sharp, broken character of the pulverized ore material produced.
As will be further noted from FIGURE 2, each cutter blade 48 is most desirably disposed at an acute angle to the radius and is angle-d forwardly, or in other words, is in a plane perpendicular to the plane through a tangent to the peripheral edge of the disk at a location ahead of each respective blade in the direction of rotation of the disk so that in striking the materials the blades will impart a radial and inward component of force against the centrifugal forces developed so as to cause increased turbulence and kimpact between the materials. Somewhat the same effect can be produced by the modified forms of blade elements shown in FIGURES 3 and 4 when substituted for the cutter blades 4S on the rotor. In FIG- URE 3, a cutter blade 7d is illustrated having an langularly offset portion 71 interconnecting generally radially extending portions 72 and 73, and which would be, for example, inserted in correspondingly shaped slots, not shown, at spaced intervals around the outer peripheral surface of each disk in the same manner as the blades 48. Again, the angularly offset portion 71 would tend to impart the same action to the materials as the angularly oifset cutter blades 48. Similarly, in FIGURE 4, the cutter blade 75 is of generally serpentine or S-shape-d conguration to provide curved angular surfaces which upon impact will effectively throw or spray the materials in different directions against other particles or materials.
In reducing the ore materials to size in the apparatus of the present invention, preferably the shell and rotor are rotated in opposite directions so as to create high effective speeds within the shell for the grinding operation. As the ore material in introduced through the feed hopper the relatively thick crusher blades in cooperation with the top row of cutter blades 48 on the rotor will initially crush the materials prior to passage to the next stage through the space between the upper disk and shell. In each stage the particles are thrown outwardly by centrifugal force and the rotating blade faces will catch some of the particles causing them to y back and strike other particles or to strike the wall; and as previously mentioned it is thought that the blades 44 and 48 cooperate with one another to cut or slice through particles trapped therebetween, again as indicated by the sharp, broken character of the resultant finely ground particles obtained, and as opposed to ground, pebble-like grains customarily obtained when materials are subjected to impact alone. In any event, during each stage the materials will be held until reduced suiciently to pass to the next stage for finer grinding. In this way, also, the materials are somewhat classified in the grinder since those of the same characteristics will tend to be pulverized and pass at the same speed through the grinder. For wet grinding operations, water may be introduced through the inlet tube and sprayed through the openings 54 into the interior of the shell so as to wet the materials as they are being ground. Also, chemicals may be sprayed in the same manner into the interior of the shell; or by closing the openings 54 the chemicals may be permitted to pass downwardly to exit through the lower end of the tube and to intermingle an-d react with the ground particles leaving the final disk stage.
From the foregoing, it will be evident that the grinding apparatus of the present invention is conformable for use in the pulverization and treatment of various different substances. It is especially effective in that the materials are subjected both to cutting action and impact under extremely high speeds, so that depending upon the nature and characteristics of the materials, some of course may be more effectively ground by cutting whereas others will be more effectively pulverized by impact against the blades and wall of the shell. In addition, the design and construction of the rotor and especially the drive shaft enables wet or chemical treatment of the materials in a single operation and within a single compact housing.
It is therefore t-o be understood that various changes and modifications may be made in the design and construction of the preferred land modified forms other than those illustrated and described, without departing from the spirit and scope of the present invention.
What is claimed is:
1. In a pulverizing apparatus, a cylindrical housing being disposed on a generally vertical axis and having a gravity feed inlet at the upper end thereof and inwardly directed, circumferentially extending housing 4blade elements disposed in axially spaced relation along the inner wall surface of said housing, a rotor being concentrically mounted for rotation within said housing including a central drive shaft and a series of disks keyed for rotation on said drive shaft in axially spaced relation therealong with the outer peripheral edge of each disk being disposed for rotation intermediately between adjacent rows of circumferentially extending housing blade elements and spaced, gene-rally radially extending rotor blade elements mounted in fixed relation to said disks being disposed normal to said housing blade elements for rotation through the axial spaces formed between adjacent housing blade elements said rotor blade elements being in the form. of relatively flat, generally rectangular plates projecting into the axial spaces formed between said housing blade elements on said housing and said housing and rotor blade elements cooperating to pulverize material introduced into said housing.
2. In a pulverizing apparatus according to claim 1, said housing blade elements lbeing formed of relatively flat annular plates disposed in a series of axially spaced rows along the inner surface of said housing, and the plates in each row being disposed in spaced circumferential relation to one another and in staggered relation to the plates in adjacent rows.
3. In a pulverizing apparatus according to claim 1, the outer peripheral edges of said disks being arranged in closely spaced relation to the inner surface of said housing and the spacing between said disks and the inner housing surface being progressively reduced to control the size of materials advancing past each of said disks in the direction of travel of material through said apparatus.
4. In apparatus for pulverizing and treating materials, the combination comprising a frame, `an outer shell defining a generally cylindrical chamber including a materials feed inlet at one end of the chamber and a treatment chamber communicating with the opposite end of the chamber, fa rotor concentrically disposed for rotation within said chamber including a hollow drive shaft projecting inwardly through the inlet end of said grinding chamber and terminating at the entrance to said treatment chamber to define a delivery tube for the passage of fluid materials through said shaft into said treat-ment chamber, and said -rotor and shell cooperating to pulverize materials introduced through said feed inlet and to advance the materials in pulverized form into said treatment chamber.
5. In apparatus according to claim 4, said hollow drive shaft being defined by an inner drive tube and an outer drive sleeve, shear pins mounting said drive sleeve in outer concentric relation to said drive tube for rotation therewith, said drive tube and outer concentric vsleeve being provided with aligned openings at spaced intervals therealong for discharging fluid materials into said cylindrical chamber.
6. In apparatus for pulverizing and treating materials, the combination comprising a frame provided with spaced end-support bearings, an outer shell 4defining a generally cylindrical pulverizing chamber including a materials feed inlet at one end of the chamber and a generally conical treatment chamber communicating with the opposite end of the said pulverizing chamber, said treatment chamber terminating in an outlet tube journaled in one of said bearings, a rotor concentrically disposed for rotation within said pulverizing chamber including a hollow drive shaft journaled in the other of said bearings and projecting inwardly through the inlet end of said pulverizing chamber t-o terminate at the entrance to said treatment chamber, said drive shaft being provided with spray openings at spaced intervals within said chamber.
7. A pulverizing apparatus comprising an outer shell of generally cylindrical configuration having a feed inlet at one end and an outlet at the opposite end, a plurality of rows of circumferentially extending plates intruding from the inner wall surface of said shell at axially spaced intervals along the length thereof, the plates in each row being disposed in spaced circumferential relation, a rotor mounted for rotation within said shell including a drive shaft mounted concentrically Within said shell and a plurality of generally circular disks mounted in axially spaced relation on said drive shaft with the outer peripheral surfaces of said disks being spaced intermediately between adjacent rows of said plates, the spacing between said disks and the inner wall surface of said shell being progressively reduced in the direction of travel of material through said shell, at least one generally radially extending rotor blade being affixed to each disk to extend into the spacing formed between adjacent rows of plates and in planes substantially normal to said plates whereupon rotation of said rotor Within said shell said rotor blades are advanced through the spacing formed between adjacent blade rows to cooperate with said plates in pulverizing ore materials introduced into said shell.
8. A pulverizing apparatus according to claim 7, each rotor blade extending substantially in a radial direction and projecting axially from opposite sides of the disk into the axial space formed between the rows of plates on said outer shell.
9. A pulverizing apparatus according to claim 7, said rotor blades each being mounted within a slot on a disk in a plane perpendicular to the plane through a tangent t-o the peripheral edge `of the disk at a location ahead of each respective plate.
10. A pulverizing apparatus according to claim 8, said rotor blades being in the form of relatively flat plates mounted in open, radially extending slots in said dishes.
11. A pulverizing apparatus according to claim 8, each rotor blade being generally S-shaped in cross-section for insertion in a correspondingly shaped slot in a disk to project axially from opposite sides of said disk into the space between adjacent housing plate rows.
References Cited UNITED STATES PATENTS 1,758,010 5/1930 Pettinos 241-188 X 2,573,129 10/1951 Dulait 241-275 X 2,700,511 1/1955 Denovan 241-154 2,922,450 l/l960 Blarbee 241-261 2,954,173 9/1960 Dunwody 241-41 X 3,111,248 11/1963 Pierson 241-190 ROBERT C. RIORDON, Primary Examiner.
D. G. KELLY, Assistant Examiner.