US2110850A - Crushing method - Google Patents

Description

March 8, 1938. E. B. sYMoNs CRUSHING METHOD Filed Feb. l0, 1934 5 Sheets-Sheet 1 h www@ E. B. SYMONS CRUSHING METHOD March 8, 1938.

Filed Feb. lO, 1934 3 Sheets-Sheet 2 March 8, 1938. E. B. sYMoNs 2,110,850

CRUSH ING METHOD Patented Mar. 8, 1938 PATENT OFFICE CRUSHING LIETHOD dgar B. Symons, Hollywood, Calif., assignor to Nordberg Manufacturing Company, Milwaukee, Wis., a corporation of Wisconsin Application February 10, 1934, Serial No. 710,591

3 Claims.

My invention relates to crushing methods and has for one purpose the provision of a new crushing method, operating on a new principle and effecting a crushing or breaking down of larger particles to particles of small size with a minimum use of power and a maximum crushing speed and effectiveness. Another object is the provision of a novel method of impact crushing, whereby material moved along a given course, for ample by gravity, is caused to take a substantially instantaneous change of direction by impact. It may thereafter be arrested or caused to take a second change of direction by a further impact, giving two stages of reduction at a single operation. Other objects will appear from time to time in" the course of the specification and claims. One apparatus employed in the practice and process herein described and claimed, is illustrated, described and claimed in my co-pending application No. 710,592, illed February 10, 1934. "se-- I illustrate my invention more or less diagrammatically in the accompanying drawings, wherein- Figure 1 is a diagrammatic side elevation of the device;

Figure 2 is a plan view;

Figure 3 is a vertical section through the impact portion of the device;

Figure 4 is a horizontal section on the line 4- 4 of Figure 3;

Figure 5 is a section on the line 5 5 of Figure 3;

FigureV 6 is a section on the line 6-6 of Figure 3.

Like parts are indicated by like symbols throughout the specification and drawings.

'Referring to the drawings, I show a mechanism which may be used to practice my method, though other means might be employed. I illustrate generally a device for elevating material, by conveyors or the like, for a free gravital drop. It will be understood, however, that the propulsion of the material into the impact zone, preferably obtained by a free gravital drop, may be obtained by other methods or means of propulsion.

Referring to the drawings in detail, A generally indicates any suitable bin or source of supply of the material to be crushed. This indication'is intended to be diagrammatic and clearly material from another conveyor, mine car or the like might be delivered to the device without the intermediary of a bin. For purpose of illustration, however, I illustrate the bin A and a discharge chute or spcut A1, with associated forwardly extending side guide Walls A2. A3 il` lustrates any suitable conveying means for elevating the material to be dropped and crushed.

I illustrate it as an endless conveyor passing about a lower pulley A4 and an upper pulley A5, which may if desired be driven through the drive pulley A6 with its belt A7 extending to any suitable power source. It will be understood that in this form of device, material discharged to the conveyor A3 will move in the direction of the arrows upwardly along the conveyor in response to the movement of the conveyor through its closed path. 'I'he side walls A2 serve to prevent any side escape of the material adjacent the point of delivery from the spout A1.

As the material passes upwardly along the conveyor A3 it is eventually discharged when the conveyor passes about the pulley A5, and drops down the vertical guide passage B. Assuming that a mass of mixed material is discharged down the passage B, with dust, fines and the like, mixed in, it may be advantageous, in order to prevent waste of crushing power, to remove some of the fines. I may eiect this by any suitable screening along the path of the conveyor A3 but find a practical solution to be the pro, vision of air inlet and outlet apertures in the passage B, whereby a blast of air may be blown across the passage, transversely of vthe path of drop of the material. 'I'his blast of air will carry oi a substantial proportion of the dust or nes. I illustrate therefore, an inlet passage B1, outlet passages IB2 and air propelling means B3, whereby the fine material may be carried oil. It will be understood, of course, that such passages are screened as at B4 or provided with mesh of such size that the particles desired to be crushed cannot escape. The use of this preliminary air cleaning in many circumstances is helpful but the crushing method may be used without it.

Assume that the material to be crushed has been dropped by the conveyor A3 or by any other suitable means, into the top of the passage B, and that it is falling downwardly through said passage. It will be understood that the passage B may be of such length that the material, if dropped on a fixed surface or anvil, would be moving fast enough to be crushed by the impact of its gravity accelerated drop. However, I obtain a more efficient crushing action by employing a moving impact member provided with one or more impact faces E9, the speed of movement and the angle of which, in relation to the drop of the particles along the passage B, is such as to cause an immediate stoppage and change of direction of the individual particles. 'Ihis reduces to a minimum friction or abrasion of the impact surface, which would otherwise be very great, and cause a redirection of the particles, as shown in Figure 3, along a new direction of travel, at the end of which the particles may again be arrested by a second crushing impact against the plates G0. It will be understood that whereas preferably the speed of the particles as they move along the passage B is sumcient to cause their crushing or separation upon impact, I may rely only partially or in some circumstances little or not at all, upon the actual drop of the material and, by speeding up the impact member, may obtain a crushing separation by the rotation of the impact member through the falling stream of particles. l It will be understood, however, that in the form shown in the present drawings the passage B may illustratively be considered to be of sufficient height to impart to the particles a velocity suiiicient to cause their crushing in response to a stoppage at the end of their fall. The stoppage and change of direction causes a very substantial crushing or reduction in size of the particles and the particles are directed in a stream against the second impact member G0, where they receive a second impact, and thus are subjected to two stages of reduction in immediate succession.

In the practice of my method, the high gravity spout or chute B is an important factor, as it imparts to the falling particles a gravital speed or acceleration sufcient to carry substantially all of the falling particles into the path of the impact members El. Tne height ofthe chute B is so related to the peripheral spacing of the members E'1 and to the speed of rotation of the rotor, that all or substantially all of the particles are contacted by a full face impact, which prevents, or reduces to a minimum, the glancing blows against the upper edge of the impact members E", which would otherwise prevent the substantiallyinstantaneous and complete change of direction described elsewhere herein and diagrammatically illustrated by the arrows and the stream of particles shown in Figure 3.

Referring to the specific structure for obtaining this result, I provide a housing generally indicated as C, which includes the top portion C1, the rear wall C3. the forward wall C3, and side walls C4. C5 indicates any suitable lower discharge chute which has an inclined wall C0 and if desired an intermediate inclined wall C".

The housing C may be fixed upon any suitable foundation D, as shown in Figure 5, and adjacent the housing are bases or supports D1 for any suitable bearing systems D3 in which rotate the ends D4 of the shaft D3. D0 is a drive pulley for the shaft D3 which may be in communication with any suitable power source. I illustrate, for example, in Figure 2, the belt D0 and the motor D'1 with its drive pulley D0. It will be understood that the shaft D3 may be rotated, at a desirable speed or speeds, by the actuation of the motor D". In order to minimize wear of the bearings and undue strain of the shaft and rotor, I have illustrated in Figure 5 the bearing members D3 as being cushioned in rubber sleeves D15 mountedl in split bearing housing D10.

Secured to opposite sides of the rim D10 and the transverse ribs D13 are the side rings indicated as E. These rings may be channeled as at rim D10. Each ring is shown as being formed of three separate sections. These sections are secured to the rotor as by bolts E3 and tie plates E3. The bolts E3 pass through apertures in the rim D10 or the transverse ribs D13 and smaller bolts E4 pass through the tie plates E3 and the adjoining free end of one of the ring sections E and are connected at their inner ends with interior wear plates E5 as shown for example in Figure 6. The impact plate or plates proper indicated as E", rest on the forward inclined faces of the transverse ribs D13. Each plate has a. laterally extending lug E0 at each side, which lugs are seated in corresponding slots El in the side plates or rings E. In order to hold the wear plates in place, I provide wedges E10 which slide between the opposed edges of the side ring E as shown for example in Figures 3 and 6. There is a cam or Wedge surface E11 against which a corresponding face of the wedge E10 rides and a tightening bolt or stem E13 is provided which may be drawn inwardly as byv a nut E13, the pin E13 passing through a boss E14 integral with the ange D10. It will be understood that tightening up on the bolt E13 will draw the wedge E10 inwardly along the Wedge surface E11 and cause the opposite side of the wedge E10 to lock against the lug E0 of the impact plate E". Not only is the impact plate thus firmly locked, but it is also easily removable for replacement or change. For example, the worn plate may be removed or the angle of the plate may be varied by putting in refill impact plates of varying angle. In such case the wedge E10 may also be replaced by a wedge of somewhat different shape or -contour. In order to prevent material from packing in outside of the side plate or ring members E, I provide a circular flange E30 extending inwardly from each side wall C* of the housing. This structure will be clear for example from Figure 5. In order to provide ready access to the interior of the device I may have one or more removable Walls, covers or the like. I illustrate for example, in Figure 3, the side Wall portion E31 and top wall portion E33, which are hinged as at E33 for ready removal as indicated in dotted lines.

It will be understood that as the material is dropped down the passage B and is engaged by the impact faces E", it is caused to move generally laterally in the direction of the arrows as shown in Figure 3. The particles so delivered are initially crushed at the instant of-. impact and these smaller particles are delivered laterally at high velocity. I provide an additional breaker plate structure, generally indicated as `G'. for receiving this high velocity delivery of the smaller particles and for imparting to them, by impact of stoppage, a further crushing or grinding effect. In practice if the material is delivered in suiilcient volume and' suiliciently steadily down the passage B, the smaller particles will be delivered against the breaker plate structure G at such a speed as to build up something of a mass of material on the forward face of the breaker plate, and the smaller particles will tend to strike this mass of material, causing a very substantial grinding action of particle against particle as well as of impact against the plate proper. In order to effect this result I provide an arcuate supporting wall structure G1,

herein shown as of two angular members, hinged as at G3 lfor ready removal, cleaning or the like. It is normally held ilxed as by the bolts G3 one end passing through angles G4 on the housing side wall C4. The structure G includes an upper angle G1s through which the bolts G3 pass, and which is in connection with the frame proper G1.

The impact plates proper G0, of which two are shown, are bolted to the angle or frame members G1 for ready removability. It will be noted that the contour of the plate G0 is generally arcuate, the purpose being to insure that there will be an immediate and complete stoppage of the material received by the plate and no glancing or angular blow. The speed of the rotor is such that all of the material impacted is caught by the impact faces proper E". However, this material, owing to the speed of rotation, is delivered through somewhat varying paths and the impact plates G6 are curved so that no matter whatangle the material may take in relation to its previous travel down the passage B, it will take a path substantially vertical to the opposed portion of the impact plates. In effect the impact plates dene an arc the center of which is the face of the rotor impact plate E" when it is aligned vertically with thepassage B. It will be further understood that as one of the impact plates E1 passes beyond the line 0f drop of the material along the passage B another impact platecrosses the stream before any of the material can drop far enough to engage the ange D10. Thus every particle dropped down the passage B is actually caught by one of the impact plates E" and is thereby crushed by impact, and the crushed particles are thereby projected against the -fixed impact plates G0 for a further crushing and grinding against the plate G8 and the mass of material on its surface. In other words, one charge of material delivered by an impact plate does not have a chance to drop away from the face of the plate G6 before the next charge engages it.

All of the material separated drops down across the inclined surfaces C6 or C7 and thus passes from the crusher. Under many circumstances I find it desirable to employ this crusher in closed circuit, to screen out the finer material produced by the crushing operation and to return the oversize for a further crushing. This may be done by a variety of suitable mechanisms and for purpose of illustration, I illustrate but one. I may employ the endless conveyor H passing about the lower pulley H1 and the upper pulley H2. It may be driven for example from the motor H3 through the belt H4 and the drive pulley H5, pinion H0 and the gear H". I'he material delivered from the crusher, in the form of the device shown in Figures 1 and 2, is picked up by the belt H and carried to a distribution member HB whence by chutes H0, H10 it may be delivered to screens H11, H12. The oversize from these screens is delivered by discharge chutes H13, H14 to the up-conveyor A3. The screened material may be delivered to a different conveyor H15 and thus escape fram/t e crushing circuit. f

It will be realized that whereas I have shown a practical and operative device for carrying out my method, nevertheless, I wish the description and drawings herein to be taken as in a real and broad sense illustrative and diagrammatic rather than as limiting me to the specic mechanism herein shown or to the speci/fic sequence of steps described. My method may be practiced with a variety of mechanisms without departing from the spirit of my invention.

The use and operation of my invention are as follows:

Most broadly stated, my method is directed to advancing or moving a stream of material, by gravity or otherwise into an impact zone, and there causing the substantially instantaneous stoppage and change of direction of each particle, by moving across the stream of falling or moving material an impact member or a succession of impact members. The impact member or members are set at such an angle to the falling stream and are moved at such a speed in relation to the speed of the falling particles as to effect a practically instantaneous stoppage and change of direction of each particle.

Referring to Figure 3, the impact members E9 are rotated across the path of falling particles and direct them against the impact plate G0. Their speed of movement is sufficient to effect a further reduction or breakage at that point. The plate G6 is curved because the path of movement of the impact directed material from the member E9 varies in angle as the impact member moves through the falling stream. All the material engages the impact plate G6 directly, and with no sliding or angling. This being true of the engagement of the particles against E9 as well as G0, abrasion or wear of the plate is reduced to a minimum. The rotation of the shaft D3 is at such a rate that none of the falling particles can fall through the ring defined by the rotation of the members E9 without being impacted by one of them. None of the particles can drop down onto the portion D10 of the rotor. Furthermore, the successive increments to particles delivered against the plate G0 may come so rapidly as to build up a species of sheet or mat of material. In other words, the particles which have already been broken by impact against the surface E9 are directed into the mass of particles resting against or falling across the surface of the plate G0. The result is not merely an impact breakage against the plate G0, but also a grinding of particle against particle which causes a maximum separation important for fine crushing.

Whereas my method may very efiiciently be employed in connection with a freely falling column of material, it will be understood that it may be practiced by other mechanisms. For example, the material might be allowed to` slide down an/ inclined plate into the impact zone, or it might be moved or thrown into the impact zone by other means. The particular details of the mechanism are therefore given not to limit the method but to indicate some one mechanism which can be practically used in practicing the method.

I claim:

1. The method of limiting abrasion in impact crushing which includes delivering ythe particles to be crushed in an unconsolidated stream along a predetermined and laterally limited path and at a predetermined rate of speed, rotating a plurality of impact members having faces rearwardlly inclined to the direction of movement of the particles so fed, and lying in planes parallel with their axis of rotation, through a predetermined path intersecting the path of feed of the particles, at speed sufficient to crush the particles, and which speed is effective, in connection with the angle of said impact members and the speed of feed of the particles when struck, to cause an instantaneous change of direction of the particles, without slippage of the particles across the surfaces of the impact members, and thereby projecting the particles entirely out of the path of movement of the impact members along a path generally at right angles to the faces of said impact members, and thereafter removing said particles along a path remote from said impact members. l*

2. The method of limiting-abrasion in impact crushing which includes delivering the particles vto be crushed in an unconsolidated stream along a predetermined and laterally limited path and at a predetermined rate of speed, rotating a plurality of impact members `having faces rearwardly inclined to the direction of movement of the particles'l so fed, andlying in planes parallel with their axis of rotation, through a predetermined path intersecting the path of feed of the particles, at speed sufllcient to crush the particles, and which speed is effective, in connection with the angle of saidimpact members and the speed of feed of the particles when struck, to cause an instantaneous change of direction of the particles, without slippage of the particles across the surfaces of the impact members, and thereby projecting the particles entirely out of the path of movement of the impact members along .a

l path generally at right angles to the faces of said impact members. and terminating' said projection by a secondary impact delivered by a fixed member the surface of which is normal to the path of movement of said impacted particles,

' 2,1 lasso and thereafter removing said particles alongl a path remote from said impact members.

3. The method of limiting abrasion in impact 4crushing which includes delivering the particles to be crushed in an unconsolidated stream along a predetermined and laterally limited path and at a predetermined rate of speed, rotating a plurality of impact -members having substantially iiat faces rearwardly inclined to the direction of movement of the particles so fed, through a predetermined path intersecting the path of feed of the particles, at speed sumcient to crush the particles, and which speed is effective, in connection with the angle of said impact members with respect to the direction and the speed of feed of the particles when struck, to cause an instantaneous change of direction of the particles, without slippage of .the particles across the surfaces of the impact members, and thereby projecting the particles entirely out of the path of lmovement of the impact members along a path generally at right angles to the faces of the impact members, and thereafter removing said particles along a path remote from said impact members.

EDGAR B. SYMONS.

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