US1707666A - Grinding mill - Google Patents

Description

L. HOLLAND- LETZ anmnme IILL April 2, 1929.

Filed March 15; 1926 ZSheets-Sheet 1 L e/1y 022M! (5, F5 1/5? fig? April 2, 1929. HOLLAND-LETZ GRINDING HILL 2 Sheets-Sheet 2 Filed larch 15, 1926 Patented Apr. 2, 1929.

UNITED STATES LUDWIG HoLLANn-Lmz, or cit'ovv'n mm, I a g g FACTURING COMPANY, 11 conrdmrroiq or n'miANA.

mmm, lemma is me amenmmno MILL.

Application filed March 15, mo. Serial No. 94,000.

This invention relates to a grinding mill which is capable of reducing porous materials, but is particularly, adapted for fibrous material. r

One of the objects of the present invention is to provide an improved form of grinding mill which is simple in construction and eflicient in operation. r

A further object ofthe invention is to provide a novel and improved form of'grinding mill in which a single rotary member performs a plurality of functions such as cutting the material being fed into the mill, feeding the material thus cut and, grinding the material fed thereby.

A further object of the invention is to provide an improved form of grinding mill having a combination cutting, feeding and grinding member which-is adapted ,to 00 operate with stationary portions of the mill. for recutting the material after the first cut- 7 ting operation. 1

A further object of the invention is. to provide an improved feeding mechanism in combination with a grinding mechanism whereby certain portions or ribs of the rotating menr ber co-opera-te with certain portions of the stationary member to alternately feed and cut the material during each cycle of operation of the rotating member. 7 r

A still further object of the invention is to provide a novel construction of a-grinding mill in which the tension or pressure between the rotating member and the stationary buhr may be adjusted for grinding the material into a fine, medium or course form.

These and other objects are accomplished by providing a construction'and an arrangement of the various parts in the manner here matter described and particularly pointed out in the appended claims.

Referringto the drawings, Fig. ;1 is'a rear elevational view of my improved grinding mill. I I 1 i j 1 Fig. 2 is a side elevational view partly section, taken on the lines 2.-2 in Fig. 1.

3 is a top plan view showing the construction of my improved form oi rotary cutting, feeding and grinding member.

'Fig. dis a top plan view showing the con structionpt my stationary buhr with-Jonly a portion. of the shear-ingor cutting projection shown the'reon' r f 5 a partial tragmentary sec- .tional view taken on the line 5f 5-;m 1

showing a section of one of the cutter knives and its relativeposition to the stationary portrons of the mill adjacent the rotating memher or knife. n i

Fig. 6 is fragmentary cross sectional View taken on line 6'-6 in Fig. 1 showing the constructionof the mechanism ,for adjusting the pressuretension between the grinding buhrs of the mill.

Fig. 7 is a reduced bottom plan view showing the construction of the adjusting collar. and indicator for varying the pressure or tension between the grinding. buhrs.

I Fig. 8 isa side elevational View of the hearing sleeve which rotatably supports the rotating member, and r Fig. 9 is an end elevational View showing the construction of the bearing sleeve shown For the purpose of illustration I have shown my improved grinding mill embodied in a hand operateddevice,- but it will of course be readily understood that a pulley may be easily substituted for thecrzmk handle show-n in-the drawing so as to make the same power operated.

In illustrating one embodiment of my invention I have shown the same as comprising a frame portion 10-wlzlich is providedwith laterally extending-ears or lugs 11,- which in turn, are provided with longitudinally extending slots 12.5fm reception therein of bolts 13 for securing the mill to a stationary support which may be anysuitable table or stand 14. The frame 10 is preferably circular-or disc-shaped in form; as shown at 15 and is provided with a concentrically at ranged rib as shown at 16 forreinforoingalnd strengthening the same. Extending about the periphery of the disc shaped portion 15 and preferably at rightangles with respect thereto is an alnnnliit flange 17 so as to form a disc-shaped portion on the inner side of the frame. Extending at regular intervals on the, inner side/of the disc-shaped frame .ber 15 are a plurality of cutter bars 18,:19, 20 and 21. The cutter bars 18, 19 and 261mm constructed so that their inner port-ions :Eorm the arcs of a circleas shown at18'; lQ'nrid 20', respectively,; which be said tar-b6 tangent to a cmnnmn ci rcle, concentric with the axis of'the disc-shapedmember-15 have their outer ends in the form oia straight line, assho'wn at 18", 19 lmdQO"; NSF!!- tive'ly, is tangent to a concentric with the first circle, but substantially larger than the first circle; These cutter bars extend inwardly from the base of the disc-shaped member and have their cuttmgedges lymg in a plane which 1sco1nmon to the inner edge 21 of the annularfiange 17. The cutter bar 18 in cooperation with the cutter knife hereafter described forms "see Fig. 5.

the initial cutting mechanism for cutting the material as it is fed lnto the mill and the cutter bar's 19, 20 and 21 in co-operation with the cutter knives on the rotating member tangentwith a relatively small circle which would lie concentric with the axis of the discshapedmember 15.'v Extending upwardly and outwardly at an angle with respect to the horizontal is a hopper socket 22 which may have attached thereto a hopper 23. EX-

tending' below the hopper socket and preferably as a continuation of the hopper is an outwardly extending wall 24 which formsa pocket for receiving and holding the material fed in through the hopper. Extending through the'disc-like member 15 and communicating with the-pocket 24c and hopper is an 0pening25; This opening passes through the disc-portion 15 and is in the form of substantially the shape of a heart, one edge of which is bounded by the cutter bar 18 and the other edge of which is bounded by the curved portions 26.

One of the important features of my improvedgrinding mill is'theprovisi0n of a novel construction of a rotating member whichperforms the function of cutting the material up and passing-the same therethrough, thence feeding it into the shearing or grinding buhrs. This mechanism comprises a rotating member 27 which is mounted concentrically with the axis of the stationary frame member 10 and rotatable with respect thereto. This member 27 is provided with a hub portion 28 in the center thereofand with a plurality ofcurvcd knives 29; These knives 29 are located on one-side of the rotating member 27 and are arranged at intervals of 120 degrees apart. -These knives 29 like thecutter bars 18, 19 and 20 have their inner ends in the form of arcs of circles which 1 might be saidto be tangent to relatively small circle concentric with the aXisof rotation of the rotating member and their outer ends in the-forinofarcs of relatively larger ing cuttcrbars'18, 19 and 20 so that the outer portions of the cutter knives and c0operating cutter 'bars rtss and convey the material inwardlytoward the axis of the rotating memberso that the material is confined to a reducing elliptical form where the material is finally sheared olf adjacentthe inner ends of the cutter members. It is of course understood that the cutting edges of the knives 29 move in a plane contacting with the plane of the cutting edges of the bars 18, 19, 20

and 21, so as to effect a shearing action between these cutting members. The cutting knives 29 on the rotary member 27 are ranged so as to form pocket-s or chambers therebetween', through the medium of which the material is carried from cutter bar to cutter bar of the'franic 10, on each cycle of operation of the rotary member for the re cutting operation of the material. .On each occasion that a pocket or chan'iber passes the heart-like opening 25, in the frame 10, an additional supply of material is added to the particular chamber. This operation is continuedthroughout the operation of the machine as material is being fed into the hopper.

herotating'member 27 has three apertures somewhat irregular in shape as shown at 30 extending therethrough, and located adjacent the inner curved portions of the cutting knives 29 for permittingthe material as it is sheared between the cutting knives and'the cutter bars to pass onthrough the rotating member from where it is fed by the cut by the cutting knives as shown in 5. Extending from the hub portion 28 and on the side of the rotating member 2. up posite the knlves 29 are three main feeding V ribs 33 which have broken extended portions shown at 33. These broken extended portions 33 as well as the outer portions of the main feeding ribs 33 as shown at a perform the alternate functions of feeding and shearing when co-operating with the co-acting ribs on the stationary member as will hereinafter be described; These main feeding ribs 33 extend from adjacent the inner edges ofthe apertures 30 as shown at 34; to the outer periphery of the rotating member and are in the form of substantially cycloidal curves. .By this construc on it will be readily seen that as the cutter knives 29 in co-operation f with the cutter bars on' the stationary frame inember'ltl cut the material the inclined por- 'tion 31 0f the'knives together with the inco ning material forces 7 the material through the apertures 30 after-which the inner portio-n's of the feeding ribs engage the mat thus cu andin (co-operation with certain ribs K hereinafterdescribedforces the material toward the'outer periphery of the buhrs. Extending between the main feeding ribs 33 and located on the outer portion of the rotating member are a plurality of supplemental alternate feeding and shearing ribs 35 which occupy a symmetrical position with respect to the main feeding ribs 33 so as to properly space these supplemental feeding and shearing ribs at substantially equal distances from each other. These supplemental ribs 35 are preferably broken. Interpo'sed between each of the broken portions of these supplemental feeding and shearing ribs 35 and also between the main ribs 33 and extended portion 33 are-transversely positioned symmetrically arranged shearing ribs 36. These shearing ribs. 36 co-act with portions of the feeding ribs on the complimentary buhr to shear the material passing therebetweeli; Co-operating with the rotary member 27 and positioned concentrically with the same is a stationary buhr 37. The stationary buhr 37 1 is'pro'vided with ahub 38 and has four main feeding ribs 39 extending from the hub 38 to the periphery, and are positioned in the reverse direction to that of the/main feeding ribs 33 on the rotating member 27. The.

main ribs 39 have broken extensions as shown at 39 and 40 which perform the alternate function of feeding and shearing when coacting with the co-operating ribs on the rotary member. These main feeding ribs 39 are substantially in the form of a cycloidal curve and are adapted to co-operate with the three main feeding ribs 33 on the rotary member 27 for forcing and feeding the material cut by the knives in a direction toward the periphery of the bnhrs to the grinding and shearing portions of the'stationary and rotating members. In this connection, one of the important features of my improved grinding mill is the employment of three main feeding ribs on the rotating member which .co-operate with four main feeding ribs on the stationary member so that only one of the feeding ribs on the rotating member co-operates with its co-acting feeding rib on the stationary member, thereby permitting only. one pair of co acting ribs to perform their function at one. time. In other words, by reason of having only three feeding ribs on the rotating mem her and four feedingribs on the stationary member, these ribs alternate in their-co-oper ation with the corresponding stationary feedingribs for feeding the material to the grind;

ing buhrs, thereby relieving the mill of an irregular excessive strain and the operator of intermittentburden of operating the machine than would be occasioned by having the numher of feeding ribs on the rotating member and the stationary member equal in number.

This construction of employing an unequal number of feeding ribs on the rotary member and the stationary member, respectively,

progressively brings the co-acting ribs into ribs reversely curved 0n the rotating member and stationary member, respectively, that as the rotating member is revolved the action ofthe co-operating feeding ribs in crossin one another produces a mining action and forces or presses the material betweenthe V contiguous edges of the ribs in a direction outwardly toward the periphery where it is engaged by the alternate feeding andshean I ing ribs of the respective members. The stationary member 37 is provided bet-ween each of the feeding ribs 39 with a plurality of syrn metrically. arranged su plemental alternate feeding and shearing ri 40. These ribs 40 are broken, as clearly shown in'Fig. 4, and have interposed between the broken portions transversely extending shearing or grindin-g ribs 41. I

It will be noted that when the alternate feeding and shearingpor-tions ef the main ribs33, as indicated eta and the extended portions 33 of the main feeding ribs 33 as well as p the supplemental feeding ribs 35' of the rotating member 27 are cooperatingwit-h the transverse ribs 41 ofthe stationary member 37, a

shearing of the ribs 33 and extensions 33' as well as the supplemental feeding ribs 35 co-' act with the corresponding feeding ribs 39,

39, 40 and 40 of the stationary member 37 a feeding or foreingofthe material toward the periphery of the members is-taik-ingplaee. It will also be noted that when the main fe -member 39, extensions 89 and40 as as the supplemental feeding ribs 40 co'act with thetransverse ribs 36% the rotary mam her a shearing of the material takes place. As previously pointed out,'this action of feeding and shearing is alterriateand the fact that there are a series of seven ribs on the stationary member and a series of eight ribs on the rotary member causes such a relative displacement of the series of the ribs on the two faces that in each section there can only be one pair of the series actually shearing at a time, so that the'resistanee offered to the shearing ae tion is spread out over the complete cycle of operation as to produce a practically continuous resistance in the machine, instead of an intermittent one. It will also be noted that a further spreading out of the resistance to the shearing action is secured by the-fact that theeo -opera-ti I shearing ribs of one buhrr m diverging alitt from the compel-sting feed; ing ribs of the other buhr' as to come into'" of this novel form of grinding buhr see my The stationary member 37 is provided with a laterally projecting lug 42 which is adapted to engage a bracket The bracket 43 is provided 'witha slot 44 on one side thereof for the reception of the lug 42 and on the other side thereof is provided with an aperture for the reception of a bolt 45 which secures the bracket to a portion ofthe frame adjacent the socket 22 This lug 42 on the stationary member 3 7 secures the member against rotation and at the same time permits the member 37'to adjust itself with respect to the rotary member. The rotating member 27 is ,rotat ably supported on the main frame 10 by a bearing sleeve 46. .The bearing sleeve 46 is provided with an enlarged circular portion 47 which forms a shoulder 48 for engaging a finished portion 49 of the rotating member 27. The sleeve 46 extends through the aperture 50 in the rotating member 27 and also through the aperture 51 of the stationary member 37..

The sleeve 46 is provided with a longitudinal extending bore 52. Formed in the enlarged portion 47 of the sleeve 46 and concentrical- 1y arranged with respect to the bore 52 is an annular recess 53 which forms a-seat for a compression spring The enlarged portion 47 of thesleeve 46 is further provided with laterally projecting rectangular lugs 55 on the oppositesides thereof which are adapted to be seated in recesses or key ways 56 formed in the hub 57 of the frame member 10. These key-Ways 56 engage the lugs 55 and prevent the sleeve 46 from rotation with respeet to the main frame 10.. The ma n frame member 10, rotary member 27 and.

stationary member 37 are held in their rela .tive operative positionsby a carriage bolt 58 which extendslthrough awasher 59 and sleeve 46 on one end andthroughlian adjusting collax-'60 and thumb nut 61 on the other end, the adjusting nut 61 being'in' threaded-engagement with the threadedjportionof the bolt. It will be noted by referring to Fig. ,2 of

the drawing that the end of-the sleeve 46 asshown at 46 stops shortof the washer 59 so that the sleeve 46 may move longitudinally a relatively short distance with respect to the stationary portions of the inill so that the pressure of the spring 54 is brought to bear on the grinding surf'acesof the buhrs. It will also be noted that tne finished portion. 49 of the hub 28 of therotating member is sutlicient- 1y large toengagethe innerfinished surface 57 'oflthe hub of the frame member-'10 so as tolimit theretractile movement of the grmd-- in'g surfaces withzrespect-to each other; i-lnother1important-feature of my improvedgrinding'mill is-the provision of a novel means for permitting an'adjustment of the pressure between the surfaces of the therewith. in ia bearmg boss 69 formed integral plurality of depressed recesses 62, 63 and 64.

These recesses are arranged in a series of three corresponding recesses arranged about the bottom of. the collar at intervals 0-fabout one hundred and Itwenty'degrees apart. The recesses 62 are relatively shallow with the recesses v63'and 64 at; graduated increasing depth so that when theicollar is positioned in its operative position one set of the re cesses such as'62 engage co-Ton rating lugs 65. which register with the rece in the collar. When it is desired to gm a porous or non-fibrous material; the collar is 'iositioned so that the shallowest recesses 2 e or register with the lugs65 formed onjthe frame member 10, and when it is desired to reduce a relatively harder or fibrous material the recesses 63 engage or register with the lugs 65, and whenit is desired to reduce exceptionally hard, fibrous or wetmaterial the collar adjusted so that the deepest recesses 64 engage or register with the lug 65 of the frame member 10. In order to facilitate this adjustment 1 have provided an indicator as shown at 66 which will aid the operator in properly adjusting the mill'by letting the in dicator 66 on the collar register with mar rs A, B and C, indicating light, intermediate and heavy spring pressure on the surfaces of the grinding buhrs.

From the above will be seen that by permitting the collar .60 to be adjusted inwardl withres acct tothe frame and ad 'ustin thumb l J e i nut-61' the pressure on the sprin 54 v 7 correspondingly increased, there oy proportionally increasing the pressure between the grinding surfaces of the buhrs. In other words by increasing the spring pressure, the sleeve 46: entirely transmits this increased pressure entirely upon the grinding surfaces of thehuhrs so that at the time sufficient pressure will be maintained on the cutter so asto retain them in proper cutting relation, whereby unusual tough, wet or librous materials may be readily reduced.

In the drawings I haveshown the actuating. means comprising a crank handle 67 which has a stub shaft 68 formed integrally The stubshaft 68 is journalled ly with is secured against displacen'ient from the bearing the frame member 10.. v The crank 6! bossv 69 by a cotter pinTO. Secured adjacent iii) the-gear teeth 72 formed integrally with and on the periphery of the rotating member 2?. 'From 'the above 1t will be seen that when the material is fed in through the hopper 28 it passes into the pocket 2-1 adjacent the socket 22 and passes through the heartshaped opening 25 and as the revolving knives 29 are revolved in the direction indicated by the arrow in Fig. 1 to a position where they co-operate with the cutter bar 18, the material is conveyed inwardly toward the axis of the rotating member where it is confined between the cutting member in the form .of an ellipse when it islinally cut into relatively large particles, after which they are again recu't by the knives 29 and went ting bars 19, 20 and 21, and as the material is continued to be fed it is forced through the opening 30 in the rotating member 29 and by the action of the inclined portions 81 of the knives, the material is forced'and fed to a position where it is engaged by the feeding ribs 33 of the rotating member 27 in co-operation with the feeding ribs 39 of the nonrotating member or stationary buhr 37 and by reason of the reversely curved feeding ribs of these respective members the material is forced outwardly to the alternate feeding, and sheering ribs adjacent the periphery of' these members where it is ground to the reduced form as previously described.

While in the above specification I have described one embodiment of my invention, it will of course be understood that the same is capable of modification and that modification may be employed without departing from the spirit and scope of the invention as expressed in the following claims.

What I claim as my invention and desire to secure by Letters Patent is: i

1. A grinding mill comprising a frame and a rotary member journalled on said frame having cutting means on one portion thereof, and separate feeding and grinding means on an opposite portion thereof.

2. A grinding mill comprising a frame'and rotary member journalled on said frame having cutting and re-cutting means on one side thereof, and feeding and grinding means on V the other side thereof.

, 3. A griding mill comprising a frame and a rotary member journalledon said frame having cutting means on one side thereof and feeding and grinding means on the other side thereof. c

4. A grinding mill comprising a frame and a rotary member journalled on said frame having cutting means on one side thereof, and feeding and grinding means on the other side thereof, there being an aperture in said rotary member adjacent said cutting means through which the material passes to said feeding and grinding means.

5.. A grinding mill comprising a frame and a rotary member journalled on said frame having cutting means on one side thereof, a d f edi ands elies mean on the ther d th r i her e eean aperture in said rotary member adjacent the axis thereof through which the" material passes to said'feeding' and grinding means.

6. A grinding mill comprising a frame and a rotary member mounted on said frame having a plurality of spaced apart knives on one side thereof, and feeding and grinding means on the other side thereof, there being a plurality of apertures in said rotary member adjacent said knives through which the cut material passes to said feeding and grinding means; i i

7. A grinding mill comprising a frame and a rotary. member mounted on said frame having a plurality of spaced apart knives on one side thereof, and feeding and grinding means on the other side thereof, there being a plurality of apertures in said rotary member adjacent the axis of said rotary member through which the cut material passes to said feeding and grinding means.

8. A grinding mill comprising aframe and a rotary member mounted on said frame having a curved knife on one side thereof, and feedin and grinding means on the other side thereo there being apertures in said rotary member adjacent said curved knives through which the cut material passes to said feeding and grinding means. 7

9. A grinding mill comprising a frame and a rotary member mounted on said frame having a plurality of spaced apart curved cutting knives'on one side thereof, and feeding and grinding means on the other side thereof, there being apertures in said rotar member adjacent said curved knives through which the cut material passes to said feed- .ing and grinding means.

10. A grinding mill comprising a frame, a cutter bar-mounted on said frame, a rotary member journalled on said frame, a cutter knife carried on one side of said rotary memher and co-operating with said cutter bar for cutting the'material fed into said mill, and

means carried on the other side of said rotary member for feeding and grinding the material cut by said knife and cutter bar.

:11. In a grinding machine, the combine,"

tion of a air of buhrs,-each having a plurality of ftieding ribs extending from adjacent the center thereof to the periphery, and a plurality of angularly disposed grinding ribs, whereby the feeding ribs on one buhr co-operate with the feeding and grinding ribs onthe other buhr, to alternately feed and gpiad the material passing therebetween,

one of said buhrs having cutting means on one face thereof, for cutting material previous tohgviflg it ground on the other fa thereof.

13, In a grinding machine, the combination of a pair of buhrs, eachhaving a; plurality of feeding ribs, certain of said ribs weeding rom fl iacent the mm thereof to the periphery, and a pluvahty'of gmndang ribs positioned transversely with respect to said feeding ribs whereby the feeding ribs on one buhr co-operate with the feeding and grinding ribs on the other buhr to alternately feed and grind the material passing there between, one of said buhrs having a plurality of knives on the other face thereof.

13. In a grinding machine, the combination of a pair of buhrs, each buhr having a plurality of feeding ribs, certain of said ribs extending from adjacent the center of the buhr to the periphery thereof, there being an aperture through one of said buhrs, adj acent said last named rib, and a pluralityof grinding ribs positioned transversely wlth respect to said feeding ribs whereby the feeding ribs on one of said buhrs co-operate with the feeding and grinding ribs on the other of said buhrs to alternately feed and grind the material passing therebetween, the buhr having the aperture therein being provided with a plurality of cutting knives on one v face thereof.

14-; Ina grinding machine, the combination of a pair of buhrs, each having a plurality of "feeding ribs extending'from the center thereof to the periphery, there being a greater numberof feeding ribs on one of said buhrs than on the other, a. plurality of grinding ribs positioned transversely with respect to said feeding ribs, whereby the feed-, ing ribson one of said buhrs'co-operate with the feeding and grinding ribs on the other to alternately feed and grind the material passing between the buhrs, one of said buhrs being provided with a plurality of knives on one side thereof. 7

15. A grinding mill comprising a frame, a rotary member journalled on said frame, said, rotary member having cutting mechanism on one side thereof and grinding mechanism on the other side thereof, a stationary member mounted on said frame and cooperating with the grinding mechanism on said ating with the grinding rotary member, and means whereby the pressure between the grinding surfaces of said menibers may be proportionately increased over the pressure on said cutting mechanism.

16. Agrindingmill comprising a frame,

a rotary member journallcd on said frame,

said rotary member having cuttingmechw nism on one side thereof and'grinding mechanism on the other side thereof, a stationary member mountedon said frame and co-opermechanism on said rotary member, and resilient means whereby the pressure between the grinding surfaces of said members may be proportionately increased over the pressure on said cutting mechanism. 5

17. A grinding millcomprising a frame, a rotary member journalled on said frame, said rotary member having cutting mechanism on one side thereof and grinding mechanism on the other side thereof, a stationary member mounted on said frame and cooperating with the grinding mechanism on said rotary memher, and means operatively connecting the axes of the rotary and stationary members together whereby the pressure between the grinding surfaces of saidmembers may be proportionately increased over the pressure on said cutting mechanism.

18.. A grinding mill comprising a frame, a rotary member journalled on said frame, said-rotary member having cutting mechanism on one side thereof and grinding mechanism on the other side thereof, a stationary member mounted on said frame and co-oper ating with the grinding mechanism on said rotary member, and means movable axially of said members whereby the pressure between'the grinding surfaces of said members may be proportionately increased over the pressure on said cutting mechanism.

19. A grinding mill comprising a frame, a rotary member journalled on said frame, the

rotary member having cutting mechanism on one side thereof'and grinding mechanism on the other side thereof, .a stationary member mounted on said frame and co-operatmg with the grinding mechanism on said rotary memother side of the rotary member, a stationary member mounted on said frame and'having grinding ribs co-operating with the ribson said rotary members, and adjustable spring means whereby the pressure between the grinding surfaces of said members may be varied. a I I 21. A grinding mill comprising a frame, a cutter bar carried by said frame, a rotary member journalled on said frame having a cutter knife mounted on one side thereof and. co-operating with'the 'cutter bar on said frame, a plurality of grinding ribs on the other side of the rotary member, a stationary member mounted on said frame and having grinding ribs co-operating with the ribs on said rotary members, and means including member and an'adjustable tension spring for lit) proportionately increasing the pressure on the grinding surfaces of said rotary and stationary'members. r

22. A grinding'mill comprising a frame, a plurality of cutter bars carried by said frame,.a rotary member journalled on said "frame, and a plurality ofcutter knives carried by said rotary member, there being a different numberof cutter knives on said rotary member than the number of cutter bars on said frame whereby cutting action of the various cutting members will be consecutive rather than simultaneous.

23. A grinding mill comprising a frame, a plurality of curved cutter bars carried by said frame, a rotary member journalled on said frame, and a plurality of cutter knives carried by said member, said cutter knives being curved in a reverse direction from the direction of the curvature of said cutter bars.

24. A grinding mill comprisinga frame, a plurality of curved cutter bars carried by .said frame, a rotary member journallcd on said frame, and a plurality of cutter knives carried by said member, said cutter knives being curved in a reverse direction from the direction of the curvature of said cutter bars, there being a different number of cutter knives on said rotary member than the number of cutter bars on said frame whereby the cutting action of the various cuttingmembers will be consecutive rather than simultaneous. 7

25. A grinding machine comprising a frame, a plurality of spaced apart cutter bars mounted on said frame, said cutter bars having their inner portions in the form oft-he are of a circle tangent with a small circle concentric with the axis of the frame and outer portions of said bars extending on a straight line tangent with a relatively larger circle concentric with the first circle, a rotary member journalled on said frameand having a plurality of spaced apart knives cooperating with said cutter bars and having their inner ends in the form of the arcs of circles tangent with a circle concentric with the axis of the rotary member and their outer ends the arcs of relatively larger circles, whereby the material fed into said machine is conveyed inwardly by the action of the knivesand cutter bar and compressed in the form of an ellipse and then sheared by the cutting members. V

26. A grinding mill comprising a frame, a rotary member journalled on said frame having a cutter knife on one side thereof, there being an aperture adjacent said cutter knife,

and conveying means on the other side of the rotary member extending from adjacent said aperture. I

27. A grinding mill comprising a frame, a rotary member journalled on said frame and having a plurality of cutter knives on one side thereof, there being apertures adjacent said cutter knives, and conveying means on the other side of said rotary member extending from adjacent said apertures.

28. A grinding mill comprising a frame, a rotary member journalled on said frame and having a plurality of cutter knives on one side thereof, there being a plurality of apertures arranged eccentrically of the axis of said rotary member, and conveying means on the other side of said rotary member extending from adjacent said apertures.

29. A grinding mill comprising a frame, a rotary member journalled on said frame, cutter bars carried by said frame, a plurality of s aced apart curved cutter knives carried y said rotary member and co-operating wit-h said cutter bars for cutting the material passing therebetween, there being apertures adjacent the knives in said rotary member, and conveying ribs on the rotary member on the side opposite the knives for conveying the material cut by said cutting members.

30. A grinding mill comprising a frame, a

rotary member journaled on said frame, having a plurality of cutting knives on one side thereof, forming material carrying chambers therebetween, there being an aperture in said rotary member through which material passes, and conveying means on the other side of said rotary memberadjacent said aperture.

31. A grinding mill comprising a frame, a rotary member journaled on said frame, having a plurality of cutting knives on one side thereof forming material carrying chambers therebetween, there being a plurality of apertures located adjacent the axis of said rotary member and a plurality of conveying ribs located on the other side of said rotary member adjacent said apertures.

In testimony whereof I have signed my name to this specificatioin on this 8th day of March, A. D. 1926.

LUDWIG- HOLLAND-LETZ.

Images