US2612321A - Screening mill - Google Patents

Description

Sept. 30, 195 c. L. SIDWELL ET AL SCREENING MILL 2 SHEET S--SHEET 1 Filed June 11, 1949 INVEN TORS' r/ L 5/0wz// Theodore A? .5/0we/l Sept. 30, 1952 c. SIDWELL ET AL SCREENING MILL 2 SHEETSSHEET 2 Filed June 11, 1949 INVENTOR 'Car/ L Sky we];

T7 0R/vEY5 Theodore A? Siowe/l.

Patented Sept. 30, 1952 Carl L. Sidwelland Theodore-Rfsidwell, Devertown, Ohio, assignors' to 'Carl L. Sidwell and Theodore R. Sidwell, doing Brothers, Devertown, Ohio business. as Sidwell Application June 11, 1e isjseriai'no. ,51

ourinvention relates to a screening mill. It

' has to do, more particularly, with a screening mill which is of the general type known as ball or rod mills.

It has been the practice in the past'to provide ball or rod mills which are composed mainly of a rotating screen or cylinder. However, if the tumbling action of the balls in the cylinder is the only means provided for pulverizing the ma- 1 2 Claims. (01. air-viii the cylindrical screenbut will protect the rollers from extremely large lumps or pieces I which might cause-damage thereto.

The preferredembodiment of our invention is illustrated in the accompanying drawings wherein'similar charactersof reference designate corresponding parts and wherein:

Figure 1 is an end elevational view of a screening mill constructed according to our invention;

terial in the cylinder, considerable time is re- Figure 2 is a horizontal sectional view taken quired for this operation. This is especially true substantially along line 22 of Figure 1.

if the lumps or pieces to be pulverized are large Figure 3 is a vertical transverse sectional view and hard. taken through the mill.

It is the main object of our invention to pro- Figure 4 is a detail in per p iv of h izin vide a screening ball or rod mill with additional and f eding means which controls the feed of means for quickly and effectively pulverizing the material to the crushing rollers. I larger lumps or pieces of the material to be Figure 5 is a perspective view, partly cut away, ground. of our mill. p x I Another object of our invention is to have Figure 6 is a Schema c ew ih perspective such additional means so arranged that the fi-- illustrating the driving system for the various nally sized particles must pass through the cy- Parts f the mill- I lindrical screen of the mill before being clis- Figure 7 is a diagrammat .vieW ill trati charged from the mill. one use of the mill. e

'Still another object of our invention is to pro- With reference to he drawi gs, the mill comvide a screening mill of the type indicated above prises the ficleehihg y er l Which s the which is extremely sim le and inexpensive to y mp f nul ends 2 a 3 n the p manufacture but yet whi h i very efiective in rated cylindrical wall 4. The perforations 5 in quickly pulverizing and sizing the material, thewall 4 are of selected size to permit discharge Various other objects will be apparent. O particles which h been uced to a p According to our invention we provide a ball maximum -1 Thewlinder l is supported for r rod mill which includes the usual type of c'y- 30 rotation by at least two pairs of cradling rollers lindrical screen adaptedto contain the balls or ewhich are carried by Shaft/5'1 supported by the rods along with the i na'terial to be pulverized by frame stthcturea- Preferably the mill is the tumbling action of the balls. The interior of closed Within a housing 9 attached to t e am the screen is provided with baflies or plates in 3- The cyl nd l is p d at circumferenthe usual way which aid in lifting the material ttally Spaced p n s around its erior With 10nto be pulverized and increase the tumbling action. eiiudinally extending bafiles lifting plates However, we do not rely merely upon th mm. which serve to lift the material to be pulverized bling action of the balls and material for per-v from e bottomhf the Cylinder and n the forming the milling or pulverizing operation. 4 tumbling t vWithin t cylinder I; a 11111- We provide additional means within the cylinder rality of the balls orrods i l areprovided in the for pulverizing or milling lumps or pieces of seusual n As is Well understood, the lected size but yet which are too large to pass 9 53 of the balls d material is usually through the cylindrical screen. This additional the Sole means relied o in a mill of this type means comprises milling rolls between which the t0 i hd O p e the m t ria material is fed. However, sizing means is asso- In to effectively speed p e pu e izi ciated with the rolls for preventing the extremely action, We P e additional milling a s Withlarge lumps from reaching the rolls. This sizing in h Cylinder l to du e o of e a er means selects the particles or lumps whichare particles n Size 80 that thetumbling action o too large to pass through the screen but rejects balls r can q y and e i y the extremely large lumps so that they are subth r reduce t pa s tb a m ximum size jected to the milling action with the balls 'or SO that they can pass 0 1 th b the cal rods. Thus, the additional milling means will screen. act on particles or lumps of an intermediate size, This additional milling means takes the form that ones Whlch are too large P ss hr u h Of a pair of crushing rollersl2 which are disposed 'ment of the plate 28.

within the cylindrical screen I and extend longitudinally thereof substantially at the center thereof. As shown in Figure 3, these rollers I2 structure at each end of the rollers I2 comprise.v

the bearing blocks M in which the trunnions'I-3 are rotatably mounted. These "bearing blocks I4 are slidably mounted in atransverselyextending guide I5 supported by a cross member of the frame 8. A spacer I6 is also slidably mounted between the bearing blocks I4 in theguide I5 and may have shims I1 associated therewith for 9.0--

curately positioning the two rollers I2 relative to each other. A compression spring I8 adjustable by means of a screw .l9-may also be associated with theguide I5 and sserves-tomovexone of the rollers I2 towards the other withresilienttpressure. The rollers :I2 {preferably do not actually contact but are spaced .a slight distance apart depending upon the .size of particles .to be produced. Q r

In order to preventextremely large lumps of material from reaching the rollers i=2 which might cause excessive wear or .damage thereof, we provide the feeding and sizing unit 2D. This unit is in .the' form cfaasurge bin or hopper having the sidewalls 2I which convergeat their lower edges towards each other. to icrmthezdischarge slot 22. iI'he wide .upperor inlettop .portion of the hopper is coveredqwith arcuate-bars 23a which .are substantially parallel with the periphery of cylinder I and which aredisposed V in spaced relationshipialong the :length-j-lof ;the

hopper. The ends of the bars 230. iare melded or otherwise secured to the upper edges ofthe hopper walls .2I and the-space 23+between' each adjacent pair of bars is of selected widthtopermit the ,passage of particles -or.;lumps of '-a certain size. This size-will be .an intermediate :size which is too .large to pass through the .openings .5 in .the cylindrical screen but which are not suliicientlyllarge, to cause damage .to therolls i 1-2. '.In .order to Icontrolthe discharge ..of material from the hopper unit .20 we provide along-itudi- .nally extending roller 24 whichcxtends .the complete length of the slot (22 and almost fills such slot. This rollerservesas a feeder and .agitator. An angle member 25Yi's mounted .on-ieacl-i :sideaof the. hopper unit at the .lower portion thereof adjacen't the discharge slot thereof. One of these angle members 'haslits inner edge 26 closely adjacent the roller 24 while ltheotherhasitsedge 'Nspace'd from the roller. This angle nember carries an adjustable gauge plate 2.8 which'will control the amount of material :clisc'ha-rged .by "the roller 24 throug'hthe-slot .22. This gauge :plate 218 is adjustable by the screws 29 carried by the angle 25 on which -.the plate is supported. The size of the particles which are .fed from the hopper is determined by thespac'ing of theflbars 23a and the amount is'determined by the adjust "ticles of pa er size. These particles are preferably of :such' a size that theywill pass through the openings 5 and the cylindrical screen I. 'Each of the-angle membersgfi 'furthercarr'ies a scraper plate 30 which is maintained in contact with its associated roll I2 by means of spring members 3| associated with each plate and the pivot rod 32 which is carried by lug 33 provided on angle members 25. The rolls I2 rotate towards each other as indicated in Figure 3 and with the plates 30 arranged a indicated,' they scrape'the surfaces of the rolls clean. I

In order to feed the material to be broken up into the cylindrical screen I, a supply chute 35 is provided at each end of the mill. These chutes 35 lead from a source of supply through the open- -ings 2a and 3a in the respective end plates 2 and .3. For receiving the material discharged through the bottom Of the cylindrical screen I, a flared 'chute ior hopper '36 is provided which extends up around the lower portion of the screen I.

In the operation of this mill, the heavy material to be broken up is supplied within the cylinder I which will contain the balls or rods I I The cylinderis rotated and the material will be broken up by thetumbling action in the usual way. Any particles which .are sufficiently small will drop through the openings 5 of the screen 1- into the chute 36. Some of the larger lumps in pieces fvvill .bepicked up by the baffles .ILO and will eventually'be deposited on the screen or grill formed by the .rods 23a. The extremely large lumps will not drop through the spaces 23 but if the 'lump'srare su'fiiciently small to drop through :such spaces, they enter the hopper of the unit 20. From this hopper the lumps .or pieces'wi-llbe fed through the slot 22, under the control of the agitating and ,feed roll 24, to the crushing rolls I2. The roll '2'4 will prevent "bridging .or jamming of the material in the hopper'of unit 20am the adjustment of the plate 28 will control the amount of the material fed to the rollslil. The rolls I2 will have. their bearings l4 so spaced apart that the proper, spacing of the rolls will result which will determine the size of the particlesjproduced by .the crushing action. This size should be s'ufiiciently small t'opermit .the crushed particles which drop on the bottom of the screen I to pass 'through'the-openings .5. However, if it happens that some of the particles whichpass throug the rollers I2 are larger or caked, they will be subjected to the tumbling action in the screen I which will reduce them. The balls or rods not only serve to break up the material but also keep the inner surface of the screen I clean.

The driving, -mec'hanism for the .mill is .illus- 'trated in Figure .6. 'Thejsha-fts v are provided with sprockets 36 at .one end around which a chain'3l passes. Thiswchainalso-drives asprocket i38..on the end of the rollerwM. The chain 3! is positively .driyen by, means of .a sprocket 39 carried on a drive shaft 40. This :drive shaft lI-il is driven .by-an electric motor-4l through the .meidium of a beltdrive 42. Thus, the cylinder land shaft, .23 are dri-ven positively simultaneously. The rolls I2 are driven-at thesametimeibymeans o'fa chain drive 43. This drive includes a drivring sprocket 44 keyed onshaft M! and driving sprockets 45 keyedon the ends of the shafts :46 which carry the rolls I 2.

This mill will have various applications but in .Tlligure '7 we have illustrated diagrammatically one application of it. In'this .figure, 'the mill .is indicated generally at M. It is shown associated wi'th'a screening and crushing unit of the type which may be provided ata stone quarry such as .a limestone quarry. The equipment includes the roughcrusher- A from which the material-is car- ."rie'cljto a secondlscreening and crushing unit B and then to a third crushing and screening unit C. In these various crushing and screening units, the material is successively reduced in size and separated. The finer material discharged from the unit C will be conducted by the trough 35 to the mill M. This material, for example, may be lime material which is too small for use as road aggregate or for similar usages and which includes various sizes of the smaller material. Our mill M may be employed to further reduce this material so that it will be in sufi'iciently small particles to serve as agricultural lime.

It will be apparent from the above description that we have provided a novel type of mill which although it is of the ball or rod mill type includes additional means for crushing or reducing the material. The additional means in the form of crushing rolls is protected by the sizing and feeding unit. 1

Various other advantages will be apparent.

Having thus described our invention, what we claim is:

1. A screening mill comprising a rotatable cylindrical screen having a single compartment for receiving material to be broken up and having balls or rods therein, means for supplying material into the screen, bafiles on the wall of the screen which serve to lift some of the material to the top of the screen, a pair of crushing rolls supported within this screen substantially at the axis thereof. and extending parallel to the axis and a single sizing and feeding unit supported above the rolls for receiving material lifted by the baffle and feeding it-between the rolls, said sizing and feeding unit comprising a. hopper covered with a grill which permits particles of a predetermined maximum size to enter the hopper, said hopper having a lower end with a discharge slot therein, and means for varying the Width of said slot.

2. Apparatus according to claim 1 wherein a feed roll is disposedwithin said slot and including means which drives the feed roll simultaneously with the screen cylinder and the crushing rolls.

CARL L. SIDWELL. THEODORE R. SIDWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 269,404 Gates Dec. 19, 1882 860,782 Abbe July 23, 1907 1,118,846 Dreisbach Nov. 24, 1914 1,242,423 Cover Oct. 9, 1917 2,001,549 Sandy May 14, 1935 2,193,163 Chenoweth Mar. 12, 1940

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