US1669239A

US1669239A - Pulverizer

Info

Publication number: US1669239A
Application number: US123239A
Authority: US
Inventors: Aubrey J Grindle
Original assignee: GRINDLE FUEL EQUIPMENT Co
Current assignee: GRINDLE FUEL EQUIPMENT Co
Priority date: 1926-07-17
Filing date: 1926-07-17
Publication date: 1928-05-08
Anticipated expiration: 1945-05-08

Description

A. J. GRIND'LE PULVERIZER May s, 1928. 1,669,239

Filed July 17. 1926 6 Sheets-Sheet 1 A. J. Gamma May 8. 192a 6 Sheets-Sheet 2 May 8, 1928.

A. J. GRINDLE PULYERIZHR m m m. m m

y, 1928. V w J. GRINDLE PULVERIZER Filed July 17. 19.26 6 Sheets-Sheet 4 NMMWWJ T zyf @Jmd/e A. J. GRINDLE May 8. 1928.

PULVERIZEIR Filed July 17. 1926 6 Sheets-Sheet 5 May 8. 1928.

A. J. GRINDLE PULVERI ZER 6Sheets Sheet 6 UNITED srA'rs-s PAT NT- OFFICE;

13m .nenmnm, or cnteae'o, rumors, ASSIGNOR r Gunman-um. EQUIP- 1mmcomrm, or ngmv-mg; rumors, AJCORPORATION-JOF rumors.

'flruLvEm'zEn. I a nea med my 17-; 1950; sem No. 123,289.

This invention relates" to a machine f or Figure 4 is .a central sectional'side View pulverizing various materials. For the ur- -on the, shghtly irregular line 4-4 of .Fig-

poses of illustration and not by way of hmii ure v I, up n ,tation, the invention is described as amecha- Figure 5 is an enlarged, detailed view of v 5 nism for pulverizing 00211 but it'is. to be unthe pum appearing .at the bottom of the co.

derstood that it may be equally used for the centre o Figure 4. pulverization of any suitableniaterial. Figure 6 1s a detailed plan View on the I In'br'eaking up relatively coarse fuel by line 6-6 of Figure 5/ l 4 y the "use of moving, usually rotating, breakers Figure 7 is a detailed. plan 1 view on the- .or beaters, a relatively .low'spee'd for such Irregular lin'e-7-7 of Figure 4. i 7' Q 65 mechanism is most satisfactory "for the ini- The Subject matter of the foregoing fi I tial disintegration of' the fuel: to particles ures was shown, described and claimed m of, say, a quarter 'of ,an inch in' diaineter; an earlier application, Serial N umber 1194, but subsequentsiniilar treatments of the filed January 8, 1925, and abandoned-at'the fuel, 'ieducing its particles ,-to successively instant of the filing of this application, 7.0

smaller and smaller sizes, require -succeswhich incorporatesthesame subjecbmatt'er."

fsively gincreased speeds ,of .thegbreaker or Figure 8 is-a modified form of-wheel conbeating devices to efficientlyproduce the structlon designed to support beaters which;

' final powdered fuel of ultimately desired are 'arinnprovement upon corresponding de-.

2o. linen-egg] vices 98 of the earlier figures.'- 1 8 .The object of this invention is to provide Figure 9 is a plan View ontheline 99 1 a single machine,- preferably 10118 rotating of Fig. 8. I about a vertical axis, equipped with a -plu- Fi are 10 is'an enlarged plan, detail view a rality of breaking ,or beating-Wheels of-pro- Of a eater.

Q gressively increased ,dianieterand cause-1 Figure 11 is. ax sectional, side viewthrou 'h I 'quently correspondingly"increased-circuin- FigrirelO, showing the mounting of t e ferentlal speeds to which thefuelto be dis-'- beater; j 4 y ;integrated or'pulverizod may be'passed in'a 'lheessential parts otthe invention are single operation tosecu're the desiredresult directly or indirectly sustained by a hollow, W with maximumefliciency as-to power re- .centrallylapertnred case or table 10, detach- '85 7 qui'red, space ccupied by. the nu'c'hineand. ably 'secured by bolts12 t0:"'a inultiplicityoo f' I .manual attendance. The invention further legs restmgjon'the floor 16 or the like consists. in, anovel mounting forith'e wheel; Closing the center aperture of the case novel means of fee' (1 ing.'tl-1e wheel andznovel 'and held in 'place'bgy thebo'lts 18- isahori- 3 5 breakers carried by the-.wheel. 'Theiin'Ve'nzontal flangeQO-ofa vertically disposed t'u-. no.

' ,to get out'of orderQ tion consists in mechanism capable of attain-i hula-r case 22. within which is rotatably ing the foregoing and other-objects; which" mountedvert'i'cal shaft 24,,turninglin up er 'canjbe easily and cheaply madejwhi'ch is bushing 26and lower bushing'28 mounte in.) p satisfactory in use andfriS not readilyfliabl'e said case. [The-upper endof'tu'bular case 22- a I j '"1 is closed hyashaftenclosing cap .30,'-detach-. as 'Morefpa'rticularlv "the invention consists ly held in place by any suitable meahs,'1

in numerous features and detailsof .conas screws igidly, secur dishflft 2 l struction which will be hereufter more 'fully .b t r cap. 30-.and't pper end Q b set forth in the specification and claims; ng- -iSIa-downwardly cup l is 34, hav- 1 f" 4 Referring to therlrawing's i'n',-\vhichlike gfl i i g wh Serve'si'lol! l numerals designate the same through- Q QP in P s i n tfi 'enter and tr e utthe several views: I down-four grooves t fi-on'theoutslde of .bea'r- Figure' l is a side el-vation ofmechanism; Hg 26. Shaft' 24 '1S,;/I 1 .flr i bo m, Prj0- illustrating this invention in its; preferred Yldedwlth de restmg u 011-9111 )'f0l 'n1'., anti-friction mechanism 38 Carrie by @1195 'TFigm'e 2 is p View 'e n i 9' 'P 40 S ened-by means of screw threads I ing shown -'in' section, on the irregular line 42 into the" lower ,end of; tubular 'casel'22. j

"2-2of Figure/1; v This'plug 40 isprovlf'ded with a multiplicity Figurefiisa sectional, plan view -o'n the of 'oil passa es 44entering an oil-reservoir 5 line. 3?) oi Figure 1, p g j 46 deta'chab yjsec'ured in place by-bolts fdlllo of shaft 24.

passing through flange on the bottom of tubular case 22. This oil reservoir 46 has in its bottom a central. perforation 52 through which the extreme lower end portion 54 of shaft 24 enters the bearing 56 upon the lower side of oil pump case 58, detachably secured by screws or bolts 60 to the lower side of oil reservoir 46. Rigidly mounted on shaft portion 54 by any suitable means, as, for instance, key 62 and rotatable inside of oil pump case 58 is a conventional pump wheel 64 adapted as shaft 24 is rotated to drive oil from oil reservoir 46, descending through passage 52 out through pipe mechanism 66 to T 68 through which it flows via pipe 70 to the interior of bushing 26 and via ipe 71 to the interior of bushing 28, thereby effectively lubricating all essential parts The oil from bushing 26 returns to oil reservoir 46 through the interior of case 22 and by-pass 72. The oil from bushin throug oil passages 44.

The mechanism just described aifordsa self-contained, continuously operating oiling device for the shaft 24, which insures its proper operation and the consequent prope operation of the remainder of the machine to be hereafter described, notwithstanding the continuous presenceof finely powdere fuel in which the machine of this invention is forced to continuously operate.

Rigidly secured to shaft 24 above cap 30, in the particular case here illustrated, integral therewith, is a flange 74 sustaining the inverted U-shaped hub 76, rigidly secured in place by any suitable means as, for instance,

studs 78. The lower end of this hub 76 is provided with an outwardly extending flange 80, carrying a downwardly extending cone 82 from which project air driving wings 84 rotatable inside of the top interiorrecess 86 of the table or case 10 below cover plate 85, having an annular perforation 87 of less external diameter than wheel 90 hereafter referred-to. Tightly enclosing hub 76, secured in place by. a multiplicity of bolts 88 are a plurality of fuel material disintegrating wheels 90-91--92-93 and 94, spaced apart by suitable washers 96. Each of these wheels is provided with a multiplicity of circumferentially disposed heaters 98 projecting sufficiently from the circumference of the respective wheels to operatively cooperate with the interior teeth 100 on the more or less hard grinding cylinders 101-102103 and 104, rigidly secured by any suitable means in register with the respective Wheels 90 to 94 on the inside of a stepped case 106 enclosing the wheels and rigidly, detachably secured on table or case 10 by any suitable means, as for instance, bolts 108 Wheel 94 V is made smaller than any' of the others so i that it will as shaft 24 rotates be rotated at a comparatively slow circumferential 28 returns to oil reservoir 46 speed to initially break up fuel-delivered to it through intake passage 110 in the top 106 of case 106, such fuel being guided toward the circumference of the wheel by a hub protecting plate 112, secured in position by any suitable means, as, for instance, screws 114. The heaters 98 on this wheel 94 I cooperating with the teeth 100 on opposite ring 104 reduces the fuel material initially on top of this wheel and ultimately passing it to particles of, say, a quarter inch in diameter which fall upon the next larger wheel 93. This second wheel 93, rotating at the same angular speed as wheel 94'but at a greater circumferential speed, breaks up this material into a second size of particles of fuel material which pass on to the third Wheel 92, in turn rotating at a greater circumferential speed than wheel 93, with the result that still finer particles of fuel material are delivered onto wheel 91 which in cooperation with wheel 90 of*the same size operating after it on thematerial finally reduces the material to the extreme fineness required for powdered fuel firing in which condition the fuel falls into interior recess The travel of the more and more finely divided fuel materialpast the wheels described is materially facilitated by'air entering the top of the machine through one or more suitable ports provided for the purpose. In the particular case here shown and for illustrative purposes only, theair enters three ports 116 in the top 106 of the case, the amount of air so admitted being regulated by a multiplicity of valve plates 118 mounted on a common hub manipulatable bya handle 120 selectively lockable in position by i a conventionalbolt mechanism 122 traveling in a slot 124, preferably,.but not necessarily, past a "graduated scale 126. Air is drawn through these ports116 by the suction fan 82-84 driven by shaft 24, as heretofore described. The control of the air admitted to the machine is important because too much air causes an unduecoa rsening of the product. As the pulverized fuel material drawn by this fan mechanism, just described, enters recess 86 in case 10, it is air driven out of the machine through exit port 128 to the point desired for use. The perforation 87 in plate 85 is important in that air in case 106 below wheel 90 is forced to travel inward toward shaft 24 to get to port 87 and thence out through fan 84, this at the time the beating wheels 9094 are throwing the heavy material outward in case 106.

product is coarsened, the power required to run the machine being correspondingly deamass:

creased. Disc '85 may beentirely omitted when.

comparatively coarse product is des1re d.-,' h

Actualeiiperience with this machine demonstrates that horizontally disposed j pulverizing wheels ,9094, carried by acentral terial worked u-pondecreases, produce highly efficient results not heretofore known .in-

"machines of this class.

- In order to take care f any coarse ma terial entering the machine through passage- ,110 which, for any special reason, as for instance" its actually being iron, cannot be.

" broken up by the first. wheel 94, an outlet passage130 is provided. at one sidejof the top of the --machine leading into a waste chamber of any suitable sort from which such use;

'lcs's'material may from vtimeto time be removed. In the particular ca,se..here illus trated, this. wastecliambeiutakes the form of a'pipe elbow closed by a door 134 pivoted at 136 and detachably releasable-by remov: ing the .pin 138 shown .as suspended .by. a

' acent beater 160'wh1ch is lar er than the the beater chain 140.- i Shaft 24 is rotated by any suitable means outside the structure shown in Figure 4. I In:

the particular c'aseher'e illustrated, the driving means is an electric motor 142 carried by a. conventional standard 144 secured in place by screws or bolts 146 entering cover top 106.

. One desirable advantage of the machine of this invention .is that the shaft 24 and consequently the grinding wheels 90 94 can be rotated in either direction to produce 'pulverizing action between heaters 98 and adjacent teeth. 100.. This'is of particular importance in that after one working corner of a beater wears oif round,-thus impairing the machine,"the opposite square corner can" machine. I

- The word wheel used In the claims is be utilized on reversing the rotation ot'tl e intended to include any sort of rotatable member havin or ,carrying'on or adjacent to its circum erenceone or more material disinteg'rating' device.

Th horizontal wheel machine very economical in power becausethe wheels at notime have to lift material workedupon as is the-case in vertical machines where-the wheels have to plowthrough the material lifting some of it. 3

In the modified construction of Figure 8, the case and wheel mountings a're substantially identical in function at'least with the structure I of .Figure -4. The .wheel'hub 76-82 of Figure 4 is, however, replaced ,with another wheel hub 150, having an outwardly inclined inner surface 15.2 of such 8 1 an angularity that. no dust or dirt can beat high held by centrifugal force on this conical surface 152. This wheel huh 150 is rovided' on its external, conical surface wit a multiplicity of ste $154, to each of which is rigidly attache by. means not here shown,

annular beater carrying wheels 15.6, the solid portions of such 'wheels being of substan vti'ally the same radial width,,--said wheels,

however, increasing, rogressively in actual diameter as required. y the steps 154. (See,

Fig.-, 8.) The outside circumferences. of

these wheels 156 are located inside of a stepped case 158 corresponding to case106 of -1gur'e 4.

, Located intermediate between each pair 0f-wheels 1'54 are a multiplicity of improved" heaters shown"in detail in Figures 10 and H 11. Each beater ismade with a large, relative] heavy head 162 of triangular form,- as 0 early -shown in Figure .10, extending from a hub-164 pivotally journaled upon a post or pin 166,. detachably mounted, as shown in Figures 10 and 11 on two adjacent -.parallel, horizontally disposed wheels 154.

Each one of these pins 166 has-an enlargement 168 intermediate of its length adaptd f' to take bearing in a recess I70within the adnormal perforation 172 throu for the reception of the main owerp'ortion a gym beater 160 is providedwitli aperforation 174 of suflicient diameter so that the entire pin device 166, including the enlargement 168, can. be passed upwardly out through this opening or perforation 174. The clearanceof the respective parts is such that pin 166 and adjacent beater 160' pulverized, frompassing quickly through the machine under the influence of gravity and the air current. This construction is quite important, since it prevents any great amount ofspacebetween the outeredgeso'f through i impacted by the boaters. It will also be ob-' served that I have arranged. the beatingaelevmentswholly above the discs.154 on which they are mounted. In the normal; operation.

of the wheel construction, just described,

these discs andthe grinding rin 1 which the material might pats wit iout being the entire'azvheel mechanism 150. is rotated der centrifugal force "to radial position. The mass of the. triangular arm'162 of pin 166. The wheel 154 which is above I eed inside the case with the re-" sult that aters-160 all swing outward unbeater 160 is suflicient to hold such p articular beater in extended position during all material breaking operations for which the machine is designed; but owing to the fact that the heaters, are thus extended, only by centrifugal force, any one of them canswing on pivot pin 166 .to avoid any obstruction in the path of the-beater which obstruction cannot be broken up or otherwise moved by the beater. This construction prevents breakage and dan'iage to the whole machine when solid pieces of iron or other material gets into the stream of material passing through the machine and being broken up by the beaten In other respects than those described, the modified structure of Figures 8 to 10, inelusive, operates identically with the device of Figures 1 to 7, inclusive.

When the breaking member 160 is thrown outward loy centrifugal force, viz; moved to the left as shown in Figures 10 and 11, the side 180 of the upper end of pin 166 takes bearing against surface 182 in perforation 174 which throws the side 184 of enlarged member 1.68 to the left of shoulder 186, Figure 11, and thus prevents accidental movement of the pin upward and consequent accidental release of the breaking member 160. I

Having thus described 'my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a pulverizer, a casing, a vertically disposed rotatable shaft within said casing,

a bearing for said shaft, a hub of substantially inverted U-shap'e in cross section affixed to said shaft extending downwardly around said bearing and terminating in a downwardly and outwardly flared portion at its lower end, a plurality of disintegrat ing wheels carried by said hub cooperating with said casing to pulverize material supplied to said casing, fan blades carried by said flared portion, and a plate between said wheels and said fan blades cooperating with said casing to form a fan chamber, said plate being apertured near its center whereby an air current produced by said blades draws material inward towards'the center of said casing after it has been thrown outward therein by centrifugal force due to rotation of said wheels, said fan chamber having an outlet opening in the side thereof in horizontal alignment with said flared portion of said hub.

2. In a pulverizer, a circular stepped casing the diameters of the stepped portions of .which progressively increase towards its with to pulverize material delivered into the same, a fan chamber beneath said and a waste chamber communicating with said casing through a lateral opening in the latter horizontally aligned with the space between the uppermost wheel and the top of the casing. v

3. In mechanism of the classdescribed, a pair of separated parallel rotatable wheels, a pivot pin extending through adjacent wheels, a material breaking member swingable on said pivot pin between said wheels, said pin being insertable in perforations in the wheels and breaking member and having an enlargement preventing passage thereof through the breaking member and also preventing removal thereof from securing relation to the breakingv member until said pin is moved transversely to a predetermined position.

4. In a pulverizer, acasing'having a material inletopening in the top thereof, a vertically disposed rotatable shaft within said' shaft in said casing and a plurality of horizontal, vertically spaced apart discs on said shaft progressively increasing in diameter from top-to bottom of said shaft, a plurality of heating elements on each disc and arranged in spaced relation about theperiphery of each disc, each beating element members secured be:

having a peripheral arcua-te face and having vertical sides tapering inwardly from the arcuate face toward the vertical shaft, the curved peripheral-face of each beater rotating in a path adjacentthe vertical wall of the stepped portion of the casing and said 'vertical wall having teeth which face in botha clockwise and anti-clockwise rotational di-' rcction, and'mea'ns for rotating the vertical shaft in either clockwise or anti-clockwise direction. i

6. In adevice of the class described, the combination ofa casing, a vertical shaft therein, aplur'ality of horizontal discs spaced apart, vertically on said shaft, a plu-lp rality of beatingmembers and means individual to each of said members for pivotally and detachably mounting them on the pe- -riphery of the discs and associated'devices actuated by the centrifugal force of the ro- I tating heaters on the disc for locking said beater-s from inadvertent detachable :movement.

7 7, In a'device of the class described' the combination of a casing, a rotatable vertical shaft therein, a plurality of discs horizontally'niountcd on said shaft for rotation therewith, a plurality of 'vertical pivotalpins for detachably and individually conncctiug the beating elements to the discs,

said pins being vertically shiftabldto permit the detachment of the heaters from the disc, said-heaters, discs and pins being con ,structed and arranged under the action of the centrifugal force of the heaters to lo 'tating heaters for locking the I ck' said ins from vertical'movement.

from detachable movement.

9. In a device of the class described, the combination of a casing enclosing a vertical rotatable shaft, two discs horizontally disposed and vertically spaced apart on said shaft, a plurality of beaters adapted to be mounted attheperiphery of the lower disc and between said discs, said discshaVing registering perforations, a, pivotal pin passing through said perforations, and through a registering bore in the beater, the bore of the beater havinga portion of enlarged diameter directlyunderlying the bore of, the superior discand said pin having enlarged head seating'in said bore of enlarged diam@ eter, said bores of the disc's and 'beater and said head being constructed and arrange to permit aportion of thehead to underlie a, portion of the superior disc under the centrifugal force of the rotating beater whereby se i to lock the in from endwise movement.

10. In a evice of the class described,the combination of a casing, a rotatable vertical shaft therein, two discs horizontally mounted orf'said discs and spaced apart vertically thereof, said discs having registering bores, a heater adapted to bepivotally mounted between said discs, said beater having a registering bore provided with an enlarged mouth portion, a pivotal pin passin through the bores of the two discs andof t e beater, said pinhaving enlargedhead lying in the enlarged bore of the "beater and said pin beingvertically removable to permit; the detachment of said heater and means-constructed, and arranged to permit "dutward movement of said pin under the action of the centrifugal force of the rotating beater for" locking! the pin against endwise movement.

11. In a pulverizelg a casing having a' material inlet opening at-its top, a vertically disposed rotatable shaft within said casing, a hub com rising an inverted substantially conical sliell havin its small upa per end closed aboutthe she I; and its lower end spaced therefrom and enclosed by the casing, but spaced therefrom to form a chamber, heaters carried by said hub to rotate within said casin' ,an'd airpropelling vanes mounted on the bower end of said hub to rotate within the chamber to draw the air through past'the beating members during their rotation. 1 v 12. In a pulverizer, a casing, a verticalshaft rotatable within said casing and a grinding ring mounted on the interior of said casing and provided "with working surfaces, pulverizlng means having "disks on said shaft and carrying pulverizing heaters adapted to rotate and co-operate with the working surfaces of the grinding'ring, a plate located below said ulverizing means to enclose them and to "orm a pulverizing chamber above said plate concentrically about said shaft, said plate ,extendingffrom the outer part of the casing'inwardly toward the shaft and terminating short of said shaft to form a discharge opening. 13. Ina pulverizer, a casing, a vertical shaft rotatable therein, pulverizing means rotatable within said casing and including i a plurality of' verticallyspacedapart imperforate discs having beating elements on their'peripheries adapted to rotate closely adjacent the wall of the casing, a plate extending across thebottom of said casing below the pulverizing means to enclose them, said plate having its innerportionspaced from the shaft to form 'a discharge for the pulverizing means, and an air blower on the shaft beneath the plate for moving thepul verized material-from the casing.

14. In a pulverizer, the combination of a casing,.a; vertical, rotatable shaft bearing a-vertical series of pulverizing heaters there- 'on, a material inlet for the top of the casing, 'a pu'lverizedmaterial discharge for the hottomoof the casing, an outlet at the top of said casing in the horizontal plane of the uppermostbeate'i of the series for the discharge of non-pulverizable material.

15. In :a pulverizer, the combination of a casing having a stepped inner surface, a ver-' tically rotatable shaft within said casing,

a 'material inlet at the top of the casing,

a vertical series of rotatable plates on said shaft and increasing in diameter from the 120 topjof the series downwardly, said platea having heaters rotatable past the vertical wall portions of the stepped inner wall of the casing, the uppermost. vertical wall opposite the top beater having an *opening. thereinto discharge 'non-pulverizable material.. a 16. In a pulverizer, the combination of); casing, a vertical rotatable shaft havlng a vertical series of pulverizing heaters there- ,1

on, a material inlet at the top of the casing,

a plate rotatable with the shaft and. located. beneath the inlet, and an outlet at the top of the casing on the "horizontal level of the uppermost heaters and in their path of travel, for the discharge of non-pnlverizable material.

.17. In a pulverizer, a casing having an inner circular wall provided with angular pro jections facing both clockwise and countercasing, a vertical shaft rotatable therein, a

substantially conical hub mounted on said shaft to rotate cth'erewith, pulverizing members rotatable with said shaft, means for feeding material into the top of said casing and for discharging the pulverized material from the bottom of said casing, lubricating means for said shaft, an air blower carried by the lower part of said hub for blowing thepulverized material from the casing, the

inner face of said conical hub' being outwardly inclined and of such angularity as to preventdust andmaterial from accumulating thereon under the action of the centrifugal force created by the rotating hub.

19. In a pulverizer, thecombination f a casing having a stepped inner surface, which progressively increases in diameter from top to bottom, a series of vertically spaced plates rotatable in the casing, and likewise gradually increasing in diameter, beatlng elements on the periphery of each plate, each heating element traveling in a path close to the vertical wall of the stepped portions of the casing,- and an air blower disposed beneath the last of said series of heaters for drawing air through the heaters.

20. In a pulverizer, a casing, a rotatable shaft therein, a beater, means for detachably and pivotally mounting said beater on said shaft whereby said beater is rotated by said shaft, and means for automatically locking the beater against detachment during the rotation of said heater.

21. In adevice of the class descrihechthe combination of a casing haviit gz a grinding ring on its inner wall provided "with work.- ing surfaces, a vertical shaft rotatably mounted in said casing and carrying a series of vertically disposed spaced apart discs the outeredges of which lie close to and rotate .pastthe working surf-aces of the grinding ring and a plurality of heating elements mounted on the periphery of each disc, said heating elements having their outer beating surfaces flush with the peripheral edges of the disc and adapted, by their rotation close to the working surfaces of the grinding ring,

aeaaase to cause the pulverization of the material passing through the machine.

22. In a device of the class described, the combination of a casing having an inner surface arranged instepped formation and gradually increasing in diameter from the top toward the bottom of the casing, the inner vertical walls of said casing having working surfaces thereon, a shaft vertically rotatable in said casing and provided with a .plurality of imperforate discs gradually increasing in diameter from top to bottom of the shaft, said discs having a plurality of heaters mounted on the peripheral portions of each disc with the outer edges of the heaters lying substantially flush with the peripheral edges of the discs and the outer peripheral edges of said discs and heaters rotating close to the working surfaces of the casing so as. to pulverize the material passing through said casing.

23. In a device of the class described, the combination of a casing having working surfaces on its inner walls, a vertical shaft rotatable in said casing and provided with a plurality of vertically disposed and spaced apart'discs and a plurality of beating elements mounted wholly on the upper faces of the peripheral portions of said discs and adapted to co-operate with the working surfaces of said casingto pulverize the material passing throughsaid casing, said discs having their outer edges disposed substantially flush with the outer edges of the im-. perforate discs and lying adjacent the working surfaces of'the casing.

24. In a pulverizer, a casing, a vertical shaft rotatable within the casing, agrinding surface formed in said casing and pulver-' izing means adapted to co-operate with said grinding surface, said means comprising a disc supported from said shaft and heaters mountedv on said disc in position such that their outer faces are disposed adjacent the grinding ring and co-operate therewith to pulverize material passing therehetween,

. said disc having peripheral portions extending between the heaters adjacent to the grinding surface to direct material being pulverized between the outer faces of the heaters and the grinding surface.

25. In a pulverizer, a casing, a vertical" mounted for rotation within the cas- 7 v disc supported by saidshaft and extending outwardly therefrom toward the casing, gheaters carried by said disc in positions'o "that their oiiter ends may move adjacenii'i the casing, the peripheral edge of the dis extending between adjacent heaters in line igiwith the outer edges thereof whereby material to be pulverized may not pass between adjacent heaters. i 1

26. In a pulverizer, a casing having an interior peripheral .grinding'--surface, a rotatable shaft arranged within the casing and pulverizing means carried by said shaft in position to swing adjacent said grinding surface to co-operate therewith to pulverize material passing therebetwecn in a direction "parallel to the axis of said shaft, said grindi'ng means including a hub secured to the shaft, an annular disc carried by'the hub and heaters carried at the peri may of the disc, the disc being extended, etween the heaters toadjacent the grinding surface to prevent the passage of material to be pill" verized past the heaters except along a path between theouter surface of the heaters and the grinding surface.

27. In a pulverizer, a casing, means formed in said casing providing grinding surfaces, a, shaft mounted for rotation in the casing, pulverizing means carried by said shaft in position to swing adjacent sald surfaces and co-operate therewith to-grind ma-.

formed in said casing providing grinding surfaces, a shaft mounted for rotation in the casing, pulverizmg means earned by sald shaft in position to swing adjacentsaid surfaces and co-operate therewith to grind material passing therebetween, said pulverizing means in'clu-ditng a plurality of discs arranged in spaced relationshlp, said dlses being carried by said shaft, and beaters mounted on said discs in position to co-operate with a said grinding surface 'to'form a pul verizing stage, 'said casing having means whereby the work material may be discharged from one stage into the succeeding stage at points spaced withinthe periphery of the disc'thereof.

\ 29. In apulverizer a casing, a vertical shaft rotatable Within the casing, grin-ding surfaces formed in said casingiand'pulverizing means adapted to co-operate with each of said grinding surfaces, each of said means comprising a disc supported from said shaft and ,heaters mounted 'on said disc in position such that their outer faces are disposed adja- "ing, a hub comprising a,

cent the grinding ringand cooperate therewith .to form a pulverlzing'stage, said disc having periphgral portions extending between the heaters to adjacent the co-operating grinding surface to" prevent the passage of work material through the stage except, along a path between the outer surfaces of the heaters and the grinding surface and said casing having means arranged therein for directing Work material discharged from 05 one stage into the next succeeding stage at points spaced inwardly of the periphery thereof. I

30. In a pulverizer, a'casing, a vertical shaft rotatable within said casing, a grind- 7 I ing surface arranged on the interior of said casing and providing a working surface, pulverizing means comprising a disc carried by said shaft and pulvcrizing heaters securedto said disc and adapted to co-operate 7 with the working surface, a plate located beneath said pulverizing means to enclose it and provide a pulverizing chamber above said plate, said plate extending from the' casing inwardly to adjacent the shaft and terminating short of the latter to form a discharge opening thereabout, and air pro polling vanes mounted for rotation with said shaft and arranged beneath'said plate to draw air downwardly past said heaters and through said discharge opening.

31; In a pulverizer, a casing having an 1nlet opening in its upper; rtion s, a vertical rotatable shaftarrang within; said castially conical member per end closed" and se ,7 ed t9 the shaft and its lower edgespaced ffronzf e shaft, a series of spaced annular plates mounted on nvert'efd 'substansmaller upsaid hub, increasing in, diameter from the top of the series downwardly, said plates having heaters pivotally mounted thereon, said heaters having their outer surfaces flush with the peripheral edges of the discs and operate with the inner walls of the casing to cause the pulverization of material passing through the machine, and air pro ellin vanes mounted at the lower outer e go of the heaters during the rotation of the shaft.

In witness whe1'eof, I have hereunto .sub-

scribed my name.

AUBREY. J. GRINDLE.

adapted upon rotation. of the shaft to co- .said hub; to rotate therewith to draw air past