US2005758A - Crusher - Google Patents

Description

E. C. SHILEY June 25, 1935.

CRUSHER 2 Sheets-Shet 1 Filed Aug. 20, 1 9152 June 25, 1935.

E. C. SHILEY CRUSHER Filed Aug. 20, 1932 2 Sheets-Sheet 2 Patented June 25, 1935 UNITED STATES PATENT; OFFICE Elmer 0. Shiley, Mount Union; Pa., assignor to J.

William Wetter, Philipsburg; Pa.,- receiver for Rockhill Coal & Iron Company. Robertsdale, Pa., a corporation of Pennsylvania Application August 20,

2 Claims.

My invention'relat'es to a method of crushing coal, ores and rock in which the particles to be crushed are broken by therotative action'of one or more rolls, and to the apparatus therefor.

In carrying out my method the apparatus used may-be varied greatly and the accompanying drawings are merely representative of the general association of elements necessary to the operation of said method.

The characteristic of my invention is that the material to be crushed is transported upon a moving table or conveyor underneath a roll, or series of rolls, the apparatus being so'constructed that said transport of said material induces, or assists in inducing, the rotation of said roll in a direction parallel to said transporting motion, whereby the energy of rotation imparted to said roll is caused to crush the larger pieces of said material contacting with said roll. The crushing action thereby produced is somewhat comparable to that effected by the standardsingle'roll crusher with stationary dead plate, which latter type of crushing unit is known to all skilled in the art. The distinguishing and essential difference between my present invention and said single roll crusher is that my transporting table, which corresponds to the stationary dead plate of said single roll crusher, is a moving element and therefore is adapted to feed the coal positively under the crushing roll without the great degradation caused in said single roll crusher by reason of (a) the gravimetric fall of the particles to be crushed thereinto and (b) the unavoidable slip between said stationary dead plate and the moving roll of said single roll crushen Other advantages and diiferences will be clear from the accompanying specification and'claims hereof.

In the accompanying drawings, Fig. I is a vertical partial cross-sectionalelevation of an elemental form of apparatus employing a single crushing roll. Fig. II is a vertical cross-section of said apparatus along the line AA of Fig. I. Fig. III is a vertical elevation of a four roll type ofapparatus which I have used in practice and Fig. IV is a vertical elevation of apparatus'adapted to permit graded crushing with removal of the fines before .the recrushing operation and with facilities for hand-picking the coarser materials before the crushing operation. Like numbers indicate like parts in the drawings. It will be understood that all of the drawings are purely diagrammatic representations of the elemental structures which" I may use in carrying out my invention and that said structures may be widely departed from within the scope thereof.

1932. Serial No. 629,684

While my apparatus is equally adaptable to the crushing of any granular material such as ore, rock or coal, I shall confine the following descriptionto the crushing of coal for the sake of brevity. I i "In the drawings Figs. I and- II, I indicates a feed chute adapted to discharge'coal IS on the upper strand 2a of a transport conveyor. Said-transport conveyor is here shown as an apron conveyor of conventional type composed 10 of-said upper carrying strand-2a and a lower return strand 21), said conveyor being driven by head shaft 3, driving gear 4 and pinion 5, in the direction indicated. Said transport conveyor is also provided with foot shaft 6', which may or 'maynot beof the adjustable takeup'variety. At asuitabledistance from the-end of said feed chute l-* a rotatable roll I is located, said roll bein-gsuppo'rted through roll shaft 8, side links 9,' link shaft in and rigid support IT. Said r011 is supported at a predetermined distance above said carrying strand 2a by means of adjustment screws l2 positioned in support II and contactingwith cross member l3 connecting side links 9. Said roll I is in this embodiment shown as provided with teeth M for the more efficient crushing of the coal, but it will be understood that in this or any other embodiment of my invention, smooth face, fluted or corrugated rolls may be applied by any one skilled in the art to suit the particular material to be crushed and that where toothed rolls of the type herein shown are used, these teeth may be of pyramidal, hawkbill, or chisel-point design or of any other form known in the art. The size to which the material 'is crushed is a function of the distance between the'lowermost point of teeth l4 or roll surface '1. in the case of smoothrolls, and the upper face of transportconveyor surface 2a. This is easily --regulable 'by-means of compression 40 screws .12.

The operation of the device is sufficiently simple. Transport conveyor carrier strand2a being moved in the direction of the arrow through rotation of driving gear 4 by pinion 5 draws the lump coal from feed'chute l and transports it under roll 1, causing rotation of the latter accompanied by crushing of said lumps to a size controlled by the distance between the points of teeth 14 and surface 2a. After said crushing action the transport conveyor discharges the crushed coal over the discharge end of the con- Veyor as shown in Fig. I. If it be'desired to hand-pick the material before the crushingaction'a'sufflcient length of surface 2a is provided as indicated by the numeral 20 to permit such hand-picking of said raw lump material. Should large pieces of unbreakable material pass under the rolls, such as tramp iron and, in the case of coal crushing, exceedingly hard stone, roll I is free to lift, swinging about the axis of shaft of energy to ensure continued rotation between the passage of contacting lumps under said rolls,

but this is not always an essential condition. In those cases in which an even greater inertia effeet is desired than can be furnished by the roll itself, shaft 8 may be extended and afsuitable flywheel placed thereon.

While the apparatus just described depends entirely upon the coaction between conveyor surface 2a and lumps I 5 to induce rotation of roll I, this is not a necessary condition and in certain embodiments of my invention I may drive said roll by power from an external source, under such conditions the transport of saidlumps l5 under said roll assisting said externally applied power in the driving of said roll, the energy thusderived from said transport being supplied through driving pinion 5. I v

. While the transport conveyor shownin Figs. I and II is of the typical apron or pan type carried upon suitable drive chains, any form of conveying device suitable to the intended use may be substituted therefor, such as a rubber belt,-;a slat conveyor, a push plate feeder or the like, the essential characteristic of such conveyor beingthat it will provide a moreor less continuous forward movement of the material to be broken under the crushing roll. Said conveyor may be horizontal as shown, inclined downwardly in the direction of travel or upwardly in said direction. If a pan conveyor be used, said pans may i be of perforate construction, such as the bar type of picking belts commonly 'used at European collieries. If such a bar type conveying belt be employed the openings-between the bars may be suitable to permit the fines to discharge from the run-of-mine coal before passing under the crushing roll, or the bars may be more closely spaced so that only the fines which it is desired toby-pass before the next crushing operation will be discharged after crushing the lump by roll 1. If desired, the carrying strand of the transport conveyor may be provided with teeth or cleats to positively propel the lumps forward under the crushing roll, and thus reduce any tendency for saidlumps to slip when engaging said roll. If teeth be used, they may supplement, or supplant, the tearing action of the roll teeth ll.

Roll 1 is shown as supported from below; and freeto rise abovesurface 2a, it being held down to its work by its ownweight, but additional weights or resilient down-thrusting means may be used-for this purpose. Again said roll may be rigidly fixed in space and the resilient effect provided by the support of surface 2a, as shown in Fig. IV hereinafter described. Further, under certain crushing conditions it may be both possible and desirable to do away with all resilient support and, provide both roll I and surface 2a rigidly supported in fixed spaced relationship.

In the drawings,'Fig.'III, a-four-roll train which I have used in practice is illustrated, the crushing being carried out in a series of steps, roll 1' bringing down the lump coal to about 7 inch size, roll 1" to 5 inch, roll 1" to 2% inch and roll 1"" to 1 inch or less. 2a is the carrying and 2b the return strand of a standard inclined apron conveyor used for feeding run-of-mine coal into the screen house. With the apparatus shown crushing is carried out under conditions that'are not ideal because 'much fine coal is admixed with the lump coal passing under the various rolls and further no fines are removed between the various crushing stages. Nevertheless the overall efficiency when crushing lump alone is excellent as shown by the following tests, the coal being from the Broad Top District of Pennsylvaniar Test A2 rolls lump crushed Test B-4 rolls lump crushed I V to 5% to 1%" The carrying stand 2a of the apronconveyor in said Fig. III- is reinforced on its under side by] longitudinal supports I6 which assist to'support the'conveyor pans while under the crushing rolls. The side links 9', 9", 9" and 9' carrying the several rolls, rest on support blocks I2, I2", 12" and l2"" and said links may be rotated upward about link shafts H1, Ill", "1" and 10, and the rolls permanently swung up out of the crushingzone, if it be desired to omit all crushingor crushing to the finer sizes. Said rolls may also swing upward automatically if unbreakable large pieces are contained in the feed.

In Fig. IV, an apparatus for stage crushing with removal of the lines before and after lump crushing, and with provision for hand-picking the refuse from the lump before crushing, is illustrated. In said Fig. IV, lump screen 20 discharges the lump coal to picking section 20" of carrying strand 2a" of the lumptransport conveyor, refuse chute 2d being provided for carrying away the hand-picked refuse. The picked lump is then transported on 2a" under primary roll 1a and after crushin discharged to secondary screen 22. Undersize removed by lump screen 20 is discharged from chute 2l to undersize conveyor 25 and transported thereby to said screen 22, the fines from said undersize and said crushed lumpbeing removed by said screen 22 and dis charged through chute 23 and the oversize sent to carrying strand 211" of the secondary transport conveyor, said oversize being then crushed by secondary roll 1b and discharged by further travel of 2a to final discharge chute 24.

As previously noted, the rolls Ia and 1b .of Fig. IV are rigidly fixed in space on supports I la and 1 lb, resiliency to allow for unbreakable material being provided by carrying strand sup ports Ila and llb, held upward against the crushing thrust by springs Ia and lb supported on rigid frame members Na. and |9 b. With this construction, the rolls are held rigidly m place and any required increase in space between-said rolls and said'carrying strands is produced by the vertical deflection of said strands cause'dby the abnormal vertical stress imposed by the.

It will be clear that such plural arrangement of rolls and transport conveyors may be practiced with any desired number of rolls, conveyors and/or screens in series and that in some embodiments it may be desirable to place plural rolls on one or more of said conveyors, in accordance with the construction illustrated in Fig. III.

It will be clear from the foregoing descriptions that while the structures employing my invention may be greatly varied and many combinations of apparatus utilized within the scope thereof, all use the common basic method comprising substantially rectilinear transport of the material to be crushed tangentiallyto and under a rotatable crushing roll adapted to crush said material during said tangential transport thereunder, the method of transport ensuring that said material will be propelled at a controlled rate under said roll and that the material to the crushed will assist in rotating said roll and thereby assist in transmitting the necessary. crushing energy.

I am aware that roller fine-grinding mills have been constructed in which the roller grinding elements were rotated about their axes by revolution of the cylindrical or annular grinding pan surface but such mills as heretofore constructed permitted the roller to contact with the surface of said pan and thus continue to be rotated when no materials were present to be ground. Further all of these devices return the oversize continuously to the primary grinding roll, which return is a necessary corollary of the revolving grinding pan. Both of these features, while highly desirable in such fine grinding mills, would entirely defeat the object of my present invention, because contact of my crushing roll with my transport conveyor surface would mean pulverization of the coarsely crushed pieces and a circular path of travel of said transport conveyor would carry crushing of all such coarsely crushed particles down to the smallest size which the crushing roll could produce, since there would be no other avenue of escape for such coarsely crushed particles.

I overcome these objections inherent to such fine-grinding mills (a) by keeping the crushing surface of the roll at all times relatively remote from the carrying surface of my transport conveyor and (b) by transporting the materials to be crushed in a substantially rectilinear path so that the oversize of the crushed material is not returned by the continued travel of the transport conveyor to the feed side of the crushing roll producing such oversize but is transported to a zone of discharge, or to a supplemental crushing roll.

I therefore desire to define the expression substantially rectilinear as used in this specification and the claims hereof as indicating a more or less straight line path of travel without return, in

contradistinction to the closed circular path of travel produced in the known grinding mills above referred to, but it will be understood that I do not limit myself to a truly straight line path, said expression substantially rectilinear being intended to include paths of travel that may be of any desired curved contour provided they do not return the crushed material to the roll producing such crushed material.

crushing efficiency can be obtained, for any limitcrushed efficiency can be obtained, for any limiting size to which crushing is to be carried, by making the gap between the crushing surfaces great enough to produce a certain proportion of oversize larger than said limiting size (such procedure being commonly practiced with existing double-roll anthracite crushers) and under such conditions I may separately convey such oversize material, by means other than my transport conveyor, back to the uncrushed feed for repassing under the initial crushing roll. I

Having described my invention, I claim:

1. Apparatus for breaking coal and the like, the said apparatus comprising a roller, a mounting for the said roller, the said roller being mounted for free rotation, a conveyor for feeding coal under the roller, the said conveyor having a straight line movement in one direction under the said roller, and having a charging end portion and a discharge end' portion, and the length of the roller being substantially co-extensive with the width of the conveyor; teeth spaced apart in a direction transversely of the conveyor and carried solely by the said roller substantially radially thereof, the said roller having gravitational movement towards the conveyor, stop means to limit the gravitational movement of the roller so that it always will be spaced apart from the surface of the conveyor a distance greater than the length of the teeth on the roller, the said roller being rotated solely by the pressure of the conveyed material thereon and on its teeth, whereby the teeth on the roller adjacent the conveyor move in the same direction with the conveyor, said gravitational roller automatically receding from the conveyor upon excess volume of material on the conveyor encountering the same, substantially as described.

2. Apparatus for breaking coal and the like, the

said apparatus comprising a conveyor having a straight line movement, a plurality of toothed gravitational rollers arranged spaced apart along the conveyor, a mounting for the said rollers, each of the said rollers being mounted for free rotation to be driven by material on the conveyor passing under the said rollers, stop means to limit the gravitational movement of the rollers so that they always will be spaced apart from the surface of the conveyor a distance greater than the length of the teeth on the rollers, each successive roller being stopped closer to the conveyor than the preceding roller, each succeeding roller having its teeth spaced closer together than the preceding roller, and each of the rollers being individually capable of being raised out of service, substantially as described.

ELMER C. SHILEY.

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