US2115223A - Ore reducing machine - Google Patents

Description

April 26, 1938. H. HARDl-NGE ORE REDUCING MACHINE Filed May 16, 1934 4 Sheets-Sheet l INVENTOR HARLOWE- HARDING-E ATTORNEY April 26, 1938. H. HARDINGE ORE REDUCINGMACHINE I Filed May 16, 1934 4 Sheets-Sheet 2 88 INVENTOR HARLowE'. HARDlNG-E.

BY W ATTORN EY Patented Apr. 26, 1938 UNITED STATES PATENTOFFICE ORE rmnocmo mom Harlowe Hardinge, York, Pa. Application May 16, 1934, Serial No. 125,847

6 Claims. (01. 83-46) This inventionrelates to ore reducing macombined a separate means for classifying the chines. ore.

More particularly the invention relates to ore Another object of the invention is to provide reducing machines of the type comprising a an improved ore reducing machine in which the rotatable drum having a considerable diameter ore first discharged from the elevating means 5 and comparatively narrow width. of the machine is intercepted by a grizzly or The drum of an ore reducing machine of this screening device which separates the coarser type has a plurality of material elevating means particles from the fines and returns the coarser or buckets arranged around the inside periphery particles to the machine for further reduction, 10 thereof for the purpose of elevating the ore or and in which means are provided for delivering 10 other material to a considerable height. the fines to a device disposed outside of the ore The drum is also so constructed as to confine reducing machine and adapted to further clasthe ore'undergoing reduction to a relatively narsify the finer particles of the ore. row zone. In this way the grinding or disinte- Another object of the invention is to provide. grating of the ore is done in a closed circuit. an improved ore reducing machine in which the 15 Disposed within the drum, preferably adjadrum of the machine is mounted in a flexiblecent the bottom portion thereof, are stationary cradle adapted to move with irregularities in impact means. The impact means may be in the shape of the drum as it rotates. the form of a plurality of plates which are Another object of the invention is to provide located in the path of the falling ore discharged an improved m ans f tata ly su p rtin from the elevating means. and driving the drum of an ore reducing ma- The impact means are usually so disposed chine in which irregularities both in the motion and constructed as to support a comparatively 0f the drum and the driving means a taken shallow bed of crushed or disintegrated ore. care This shallow bed of ore on the impact means ab- Another object of the invenflm is to F 25 sorbs the shock of the oncoming ore and thereby vide an improvedore .reducmg machine in Whlch prevents excessive orundue wear of the plates means are pmvided for removing excess mate" which constitute the impact memm 1 rial from the machine in excess of a predeter- Furthermore, in ore'reducing machines of this mined amount so as to reduce the power type, means are usually provided for classifyf sumption and frictional wear on the inside of 30 ing the ore so that the fines are continuously the drum of the machine removed from the machine as new or fresh Another object of the invention is to provide material is delivered thereto. Fluid classifying an Improved ore reducing machine m wmch means, either in the form of air or water, have means are provided'for removing the ground and been used for classifying purposes.

In the case where water is used for classifyhigh above the bottom of the machine so that ing the pulverized ore, the fines are floated 2 g gg ggzg fi' g a g gfi g g and off through a suitable discharge launder. y grav According to the methods heretofore employed Another object of the invention is to provlde 40 an improved classifying system for ore reducing 40 for removing the fines, the ore remained in the machines of the above type in which, means are gnndmg clrcult reduced to fines which provided within the machine for partially claswould float off with the water or other classifysifymg the material and additional cl ssifying mg i Thls has retarfied h productive means are provided'outside of the machine for the machines smce many the the final classification of the material so as to 45 fines which otherwise would have been removed improve the character f the product produced from the grinding C remained in e and increase the efficiency of the machine. ing circuit along with the coarser particles of th object of th invention is to provide Ore undergoing reduction an improved ore reducing machine in which y the p esent invention a new method of means are provided for maintaining the load 50.

classifying the ore has been'devised so as to within the machine within the confines of the hasten the removal of thefines and therebyinelevating means. crease the productive capacity of the machine. Another object of the invention is to provide" An object of the invention is to provide an" an improved ore reducing machine ofthe char-' imp v re r ducing machine with which is acter mentioned, which is simple in construc-' 55,

partly ground material at an elevation sufiiciently 5 tion, and reliable and exact in function under all conditions of service.

The invention also comprises certain new and useful improvements in the construction, arrangement and combination of the several parts of which it is composed, as will be hereinafter more fully described and claimed.

In the accompanying drawings:-

Figure l is an end elevation partly in section of an ore reducing-machine embodying the invention;

Figure 2 is an elevator of the machine shown in Fig. 1, looking at the driving mechanism;

Figlure 3 is a plan of the structure shown in Fig.

Figure 4 is an enlarged plan of the take-off grizzly;

Figure 5 is a section taken on the line 5-5 of Fig. 4;'

Figure 6 is a detail section of one of the buckets, taken on the line 6-6 of Fig. 1;

Figure 7 is a detail of a portion of the drum supporting cradle;

Figure 8 is a section taken on the line 8-8 of Fig. 7;

Figure 9 is a vertical section taken on the line 9-901 Fig. 1, and

Figure 10 is a section taken on the line ||l|0 of Fig. 9 and showing the manner of supporting the drum supporting cradle.

While I have shown only the preferred form of the invention; it should be understood that various changes or modifications may be made within the scope of the claims hereto attached without departing from the spirit of the invention.

Referring to the drawings, the improved ore reducing machine may comprise a drum having an annular peripheral wall l2 and opposite end flanges l3 and M which depend from the wall l2. As shown by Figs. 1 and 2, the thickness of in the nature of annular rings and are open at the center, as shown in Fig. 1. In this way a certain amount of water may be accommodated in the bottom portion of the drum for a purpose to be hereinafter more fully described. The water is fed into the drum through a suitable pipe l5.

Arranged around the interior of the peripheral wall I! of the drum H and confined between the end flanges l3 and I4, is an annular series of buckets l6.

As shown in Figs. 1 and 6, each bucket l6 con-- sists of a rectangular piece of sheet material, such as plate steel, the side edges |1, |8 of which are fastened to the end flanges 3, l4, respectively, and the rear edge I9 thereof being fastened to the peripheral wall |2 of the drum, by any suitable method, such as welding, as indicated at 20,

, bolts 4|.

The side portions of the mouth of each bucket iii are contracted by means of oppositely disposed V-shaped plates 2|, 22, which are secured to the end flanges l3, M, respectively, as shown in Fig. 6.

By constructing the buckets It in the above described manner, when the drum H is rotated in the direction indicated by the arrow in Fig. 1, material or ore disposed in a lower bucket will be made to rise with the lower bucket to a considerable distance above the axis of the drum, and while thus rising will be crowded by the slanting sides 2|, 22, toward the back of the bucket, occupying a central portion of the drum until it is finally discharged over the inner edge of the bucket as the latter assumes a horizontal position, and on further ascent changes to a downwardly inclined position. Due to the shape of the side walls of the bucket, the material, when the bucket reaches the discharging position, will occupy a central position and will drop through the center of the drum, that is that space between the end flanges l3, [4. In thisway the material or ore discharged from a bucket will not spread outwardly sufilciently to fall through the openings in the end flanges l3, I4 of the drum ll.

Material or ore is delivered to the drum H from a feed hopper 25, located adjacent one end of the drum, as clearly shown in Fig. 3.

As shown, the drum H is rotatably supported in a cradle 21, comprising a pair of arcuate flexible members 28, 29 disposed underneath the drum and located, respectively, adjacent the two ends thereof.

For the purpose of supporting the cradle 21, I utilize a frame work 30 constructed preferably of structural steel and including uprights, 3|, horizontal beams 32, and diagonal braces 33. The various parts of the frame work'3li may be formed from I-beams, channels, angle-irons and the like, as shown.

The frame work 30 is mounted on suitable supporting means, such as concrete posts or pillars 34 (see Figs. 1 and 2).

The flexible members 28, 29 comprise a chainlike structure composed of a series of bars or links 35 of suitable length. The adjoining ends of the bars or links are pivotally connected together by shafts 36.

Each shaft 36 also serves to support a pair of flanged wheels 31, which are disposed between the 'bars in the manner shown in Fig. 8.

The wheels 31 engage annular tires or tracks 38 mounted on the exterior of the wall l2 of the drum II, and disposed adjacent the end flanges l3, l4. v

As shown, the wheels 31 have a single flange,

the flanges of each pair of wheels being so dis- The ends of the flexible members 28, 29 are anchored to rigid cross members 39 carried by the frame work 30, by means of blocks 40 and Interposed between the blocks 40 and the cross members 39 are resilient pads 44 formed of rubber or the like, which are adapted to absorb vibration and shocks transmitted by the drum II to the cradle 21.

In order to prevent undue lateral swinging movement of the' drum II and its cradle mounting, the intermediate bars or links 35 of the flexible members 28, 29 are formed with grooved or slotted portions 42, which are slidably mounted in uprights 43 projecting upwardly from the v the buckets I6:

foundation of the machine, as shown in Figs. 1 and 9.

For the purpose of rotating the drum ll, suitable driving mechanism is employed, said driving mechanism including an electric motor or other prime mover 45 and a flexible chain or other similar driving element 46, which is operatively connected to the drum II and in turn is adapted to be actuated by the motor 45.

The links of the chain 46 engage the teeth of a gear 41 arranged around the outer periphery of the drum II, as shown in Fig. 2.

The chain 46 is in the form of an endless loop. one end of which passes around an idler 48 ro-' tatably supported on a shaft 49 carried by the frame work 30, and the other end of which passes around a gear or sprocket 50 mounted on a shaft 5!, also journalledin the frame work. As shown in Fig. 1, the chain 46 underlies and engages a sector of the drum ii at one side of the machine.

The shaft 5| also has a large gear 52 mounted thereon, said gear being in meshing relationship with a pinion or small gear 53 carried by a shaft Shaft 54 also carries a large gear 55, which. is operatively connected with the gear 56 of the motor 45, by a flexible element, such as a chain, V-belt, or the like 51.

In this way operation of the motor 45 will be transmitted through the power transmitting mechanism above described to the drum chain 46, at greatly reduced speed and the drum II will accordingly be rotated at a comparatively slow speed.

As shown in Figs. 1 and .9, the frame work 30 also serves as means for supporting two substantially semi-circular baffle plates 60. These baflie plates are respectively disposed adjacent each end of the drum ll, so that all the material dropping from the buckets I6, is confined to a central zone between the two baille plates.

Extending through the drum Ii and supported from the baffle plates 60, are av plurality of impact means or breaker plates 6|, which are located in the path of the material falling from Two of the breaker plates 6| are supported on I-beams 62, while the remaining breaker plates are mounted on saddles 63 supported from the baffle platesisee Figs. 1 and 9).

It will be noted that the breaker plates fii, I-beams 62, and saddles 63 are arranged at a slight angle to the horizontal plane, the angle being such that the dropping material which follows a curved path strikes the breaker plates 6| substantially at right angles.

It should also be noted that the breaker plates 6| are arranged in upper and lower series, the breaker plates of the lower series being arranged in staggered relation to those of the upper series.

At a suitable position above the breaker plate 6| at the extreme right hand side of the machine as viewed in Fig. 1, and also disposed adjacent'to the ascending buckets I6, is a take-off grizzly 65.

The grizzly 65 may comprise a substantially rectangular plate which is sloped or set at an The grizzly 65 has a fiat bottom 66, open upperi and lower ends, and opposite side walls 61. The side walls 61 are disposed adjacent the bailie plates Bil, and at the lower end of the grizzly, the side walls 61 are formed with depending cars 69, which are pivotaliy connected to a frame, as indicated at 10, Fig. 5,

The outer or higher portion of the bottom 86, of the grizzly is imperforate, while the inner or lower portion of the bottom is perforated, as indicated at 68, Figs. 4 and 5. The perforated portion 68 of the grizzly constitutes a screen through which the fine material deposited on the grizzly can pass and thereby be separated from the coarser particles.

Underlying the grizzly 65 and preferably supported from the battle plates 60, is a trough H, the upper portion of which has an 'area corresponding substantially'to the area of the perforated portion 68 'of the grizzly .so that the fine material which passes through the perforations 68, will be collected.

Leading from one end of the trough H, is a ,launder or pipe 12, the purpose of which will be I hereinafter more fully described.

The grizzly 65 normally rests on and is supported by the upper edge of the trough H, as shown in Figs. 1 and 5.

The purpose of pivotally mounting the grizzly 65 is to permit upward swinging movement thereof in case any large pieces of material or other objects project beyond the discharge lip of an ascending bucket an amount sufiicient to strike the outer portion of the grizzly. In such case, when the underside of the grizzly is engaged by material projecting from a bucket, the grizzly will move upwardly about its pivots .10 and thus permit the upward passage of the obstruction without causing any damage to the bucket or the grizzly. As soon as the obstruction is removed and the bucket moves past the end of the grizzly, the grizzly will drop back to its former position on the trough H. In this way clogging of the machine at this point will be prevented.

Material falling out of. the buckets onto the grizzly will be separated, the coarser particles rolling down over the grizzly and dropping off the lower inner edge thereof, and the finer particles passing through-the perforations 68 into the trough II. The undersize or finer particles which pass through the screen provided by the perforatedportion 68 of the grizzly, flow down the launder I2 and out of the machine.

If the screen openings of the grizzly 65 are of suflicient size, complete classification of the material'may be accomplished at this point. Howeyer, since in most cases a fine product is desired and since such a fine. product can only be obtained by employing a grizzly having a fine screen, it has been found by actual practice that the use of a grizzly having a fine screen is impracticable due tothe unsatisfactory wearing qualities of a fine screen at this point. Therefore, it. has been discovered that better results can be obtained 'by employing a grizzly having a comparatively coarse screen for the purpose of separating the coarser particles from the fines and then further classifying the fines in order to separate the coarser particles therefrom and return the same to the machine for further reduction. i v

According to the present invention the fine material which passes through the screen 68 of the grizzly 65 is delivered by the launder 12 to a classifier device 15 located along one end of the drum ll. Any suitable type of classifier 15 may be employed. In the present instance I have shown a classifier along the general lines of the rotary wet classifier shown in my Patent #l,91'7,--

300 granted July 11, 1933.

The classifier 15 comprises an elongated drum 16 which is rotatably mounted on the frame work heretofore referred to, said drum being set in an inclined position with its longitudinal axis at angle to the horizontal plane, as shown in Fig. 1. The upper or higher end of the drum 16 is formed with a conical lip 11 over which the oversize material passes and is discharged into a trough or launder 18 leading to the interior of the drum I I so that the oversize is returned to the machine for further reduction.

At the lower or opposite end of the drum. 16 there is an annular lip 19 over which the fines overflow and are delivered to a trough or launder 80 leading from the machine.

The launder 12 heretofore referred to projects into the upper end of the drum 16 a suitable distance, as shown in Fig. 1. The progress of ma terial through the classifier 15 is such that the coarse or oversize material is carried toward the discharge end at the right of the drum [6, as

viewed in Fig. 1, and the fine material is carried out from the opposite end of the classifier by water overflowing therefrom.

' As shown by the dotted lines in Fig. 1 the interior of the drum I6 is formed with screw flights. 8|, which urge the coarse material toward the ferred to is of a type particularly suited for the purpose of grading the product of the ore reducing machine so that the final product will be uniform and have the desired degree of fineness. It should also be noted that the location of the classifier 15 with respect to the grizzly 65 permits gravity fiow of the material from the machine to the classifier and gravity flow of the oversize ma-- terial from the classifier back into the drum II, and also gravity flow of the fines away from the classifier. In this way the cost of operating the whole apparatus is reduced to a minimum.

In the operation of the device, material is fed into the drum I I from the hopper 25, the material falling into the buckets in'the bottom of the drum. The buckets raise the material and gradually discharge the same for violent impact against the breaker plates 6| whereby the material is comminuted and made to gravitate from the breaker plates back to the buckets in the bottom of the drum H.

In this connection it should be observed that the dimensions of the drum of the machine are of great importance. It will be noted that as compared with drums used in ordinary cleaning or washing operations, the drums are of comparatively small diameter as compared with the length of the drum. In the present instance it is. proposed to produce a distinct chipping action by the dropping of the ore on the breaker plates, and the drum H therefore is made of a diameter far in excess of that commonly employed, and as a matter of fact I find that a diameter of twenty feet or more is economically best suited for my purposes. If a drum of such diameter were made of the length of the drums usually employed in washing or grinding operations, it would be entirely unwieldy, and this is one of the reasons why I reduce the length of the drum to such an extent that the diameter of the drum is greatly in excess of the length, and the entire drum appears as being narrow, as compared with its diameter.

This construction is also advantageous in view of the fact that the drum works on principles altogether difierent from those controlling drums plane until it is reduced to a size which allows it to be carried off as fines.

' After the material has made impact with the breaker plates it drops into the buckets disposed in the bottom of the drum.

During operation of the machine the buckets l6 carry the entire load of the material within the drum with the exception of the small amount of material lying on the breaker plates 6| and the material falling from the upper buckets.

With this in mind, as the buckets rise up from the bottom of the machine, each bucket will be filled with ore, with which is mixed a quantity of water.

Due to the shape and construction of the buckets the material carried therein during normal operation of the machine will not commence to spill from the buckets until after the buckets rise to a point above the axial center of the drum ll.

As shown in Fig. 1, the grizzly 65 is located at a point above the center of the drum and below the point at which the material begins to spill from the buckets.

If the water and ore does spill below the grizzly, the machine becomes unstable in operation and is likely to become overloaded with a mixture of oreand water spilling back down the buckets. This condition increases wear and power with little or no increase in capacity of the machine, and is an undesirable method of operation. The location point of the grizzly 65 is therefore important, and when the grizzly is positioned as above described it improves and stabilizes the operation of the machine to a marked degree as will be understood.

The coarse ore will drop on the grizzly, but will not pass out of the circuit unless the particles are small enough to pass through the perforations 68, but will slide over the grizzly and fall directly down into the bottom portion of the.

drum, striking on the way down the impact or breaker plates at the right hand side of the machine as viewed in Fig. 1. However, the greatest portion of the coarse particles of material, together with a certain quantity of fines that are embedded in the coarse pieces in the buckets, will be carried on past the grizzly and drop on the breaker plates 6|, where the crushing action takes place in the manner previously described.

The finer particles of the material together with the water which fall on the grizzly 65, will pass through the perforated portion 68 and into the trough H and from thence will flow down the launder 12 to the classifier 15.

The finer particles together with the water which are delivered to the classifier 15 by the launder 12, are subjected to the classifying action whereby the coarser particles are returned to the drum ll through the launder 18 and the fines carried away by the launder 80, as has been heretofore described.

From the foregoing it will be noted that by my invention I have provided an improved ore reducing machine in which means are provided within the drum of the machine for partially classifying the ground material and additional classifying means are provided outside of the drum-ll for the final classification of the material. In actual operation of a machine constructed according to my present invention the character of the product has been improved considerably over the products of other ore reducing machines heretofore in use, and due to the construction and arrangement of the parts and the manner of operating the classifiers, the amount of power consumption and the frictional wear on the interior of the drum of the machine has been reduced to a minimum, so that the machine can be successfully used for reducing lower grades of oreon a paying basis than would otherwise be possible. a

Having thus described myinvention' what I claim and desire to secure by Letters Patent is:

1. An ore reducing machine comprising a ro- I tatable drum, impact means within the drum for receiving the thrust of the material, elevating means for lifting the material, and for discharging the same toward said impact means, a grizzly disposed above the impact means and located in the path of the material first discharged from the elevating means for classifying the material first discharged from the elevating means, means for supporting said grizzly, including pivots at one end of the grizzly and a rigidly mounted discharge trough for receiving the finer particles from the grizzly, and a launder leading from the discharge trough, the pivots permitting upward swinging movement of the grizzly in case the grizzly is struck by obstacles projecting outwardly from said material elevating means. 4

2. An ore reducing machine comprising a. frame work, an arcuate cradle resiliently supported at each end by said frame work, a drum I rotatably mounted in said cradle, means for iotating said drum comprising a flexible element operatively connected to the loaded side only of said drum, a source of power,.speed reducing means operatively connecting said source of power and said flexible element; impact means within the drum for receiving the impact of the material undergoing reduction in the machine,

elevating means on the drum for lifting the materlal and for discharging the material toward said impact means after the material. has been elevated a predetermined height; means for intercepting the material first discharged from said elevating means and for classifying the material whereby the fines are separated from the coarser particles, means for removing the fines fromthe machine, 'means for returning the coarse particles to the machine for further reduction, means for classifying the fines removed from the machine so as to separate the same into fine and'coarseparticles, and means for returning the coarse particles from the second classifier to the drum for further reduction.-

receiving the thrust of the material, elevating means for lifting and discharging the material toward said impact means in a series of laterally descending streams, a stationary grizzly disposed above the impact means and located in the path of the portion of the descending stream of material first discharged from the elevating means, means formed on the grizzly for separating the fines from the coarser particles, and means for further classifying the fines separated by the grizzly and for returning the oversize portion thereof to the drum for further reduction.

4. In an ore reducing machine, the combina tion with a rotatable drum, of impact means mounted within the drum for receiving the impact of the material undergoing reduction in the drum, buckets carried by the drum for lifting the material and for discharging the material towards said impact means in a series of laterally descending streams after the material has been elevated a predetermined height, a screen for intercepting the material in the portion of the dedischarged from the buckets for intercepting such material and for screening the same to separate the finer particles from the coarse, means located without the drum and operatively associated with said screening means for receiving the fines passing through the screening means and for classifying the same whereby the coarser particles are separated from the fines, and a launder leading from said classifying means to the interior of the drum for returning the coarser particles of the classified material to the drum for further reduction.

6. An ore reducing machine comprising a crushing chamber adapted to receive ore therein,

means within the chamber for raising and dropping the orein a series of laterally descending streams, an impact medium in the lower portion of the chamber for receiving the dropping ore, stationary screening means located in the path of the portion of .the descending stream of ore first discharged from the ore raising means for intercepting such material and for screening the same to separate the finer particles from the coarse, means for returning the coarserparticles to the crushing chamber, means located without the crushing chamber and operatively associated with said screening means for receiving the passingthrough the screening means and for classifying the same whereby the coarser par-- -ticles are separated fromv the fines, and means connecting said last named classifying means with the interior-of the drum for returning to v the drumthe-coarser particles of the classified'ore for further reduction.

' HARLOWE HARDINGE.

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