US2873920A - Crusher - Google Patents

Description

Feb. 17, 1959 $1 HOLM 2,873,920

CRUSHER Filed Oct. 31, 1955 I s Sheets-Sheet 1' INVENTOR. 5M; 63%;?

,1. C. HOLM Feb. 17, 1959 CRUSHER is Sheets-Shet 2 Filed Odt. 31, 1955 INVENT OR. .fws 6. 6494M Feb. 17, 1959 J. c. HOLM 2,873,920

CRUSHER Filed Oct. 31, 1955 5 Sheets-Sheet 3 35 E A 7 i 17 .9

Iv h INVENTOR.

Jws 5. 6 44 United States Patent CRUSHER JensC.Holm, Evanston, Ill.-, assignor to Bath Iron vyorks Corporation, Bath, Maine, a corporation of -Ma1ne Application October 31, 1955, Serial No. 543,922

'12 Claims. (Cl. 241-80) Another-object'ofthe invention is to provide a-crushing machine which discharges the reduced 'material'of proper size and recirculates the overs'ized material into the "path' ofth'e high speed fharnmers'. u

'ak'ffuit'her-object of-the inverition'isto provide" acrus'her *for i dncing -wet material.

A still further object ofthe invention is to provide a -crushing' machine for reducing 'frangible materials to fine particles and removing the particles by-an airstream.

Other and further objects will be apparent from the 'follo'viing description *taken in connection with the drawingsin'v'lhich':

Fig. l---is a longitudinal sectional view of the crusher;

Fig. 2 isa cross sectionalvlew of the'crus'her; Fig.-"3' is an endview-of the breaker and screen'mem- '"ber;

Fig. =4 is a fragmentary sectional bodiment of the rotor;

Fig. 5 is a longitudinal sectional view of the crusher :forproducing fine particles; 1

Fig. 6 is a fragmentary sectional viewyof the screen shown in Fig. 2;

'Fig. '7 illustrates a portion of ie-double row of the ibreaker bars;

Fig. 8 illustrates rec'tangularbrea'ker bars; and' -Fig. 9 illustrates -=elliptical'breaker bars. v

The crusher comprises a rotor 10 having a set of view *of "another emhammers '11 for hitting frangible material with impact blows, sending it against the rotating brea'ker means or bars 12 encircling the rotor 10. A'classifying screen '13 exteriorly encircles the breaker means and rotates therewith; The screen separates the reduced materi al by discharging the piecesof thedesired size or'less and retaining the 'oversize 'materi'al within the crusher for further -reduction by the-hammers and breaker bars. "The-material is introduced into the crusher through an'open'ing "14 -between the breaker means '12 and the frotor 10 "and is discharged through the bottom of the screen 13.

The rotor 10 is 'supported-on'the end of the shaft 34 which is coupled "to and driven 'by a prime'mover such as ian electric'mo'to'r 16. The rotating hammers =11, sub- :"scribing a hammer circle having a :diameter A (Fig. 2), have :Lsu'rfaces substantially radial :10 the shaft '34 and text ending longitudinally .t'o the axis forhitting material dropped vin the crusher. .The hammers are of the re- .placeable type and rare secured in fixed position. As fsh'own in Fig. 2, 'the hammers are adapted to rotate in one direction. Hammers .-'may be .lprov'ided l striking sur- :ranged securing the rim .21 to the plate 18 along "ice faces on both sides so that the directions of rotation of the rotor maybereversed. This is illustrated in 'the embodiment shown in Fig. 4 in which the "hammers have faces on opposite sides and are vpivotally mounted 'on'the rotor.

'The breaker means or bars 12 are spaced a distance B from the hammer circle Fig. 2, and extend longitudinally having radially extending support beams 19 stifiFening the plate 18 and rigidly securing the plate 18to'the shaft 15. The breaker bars 12 are'preferably cylindrical in shape with a longitudinal bore 20 extending therethrough.

Each of the bars are secured to the plate 18 by-means of a long bolt or threaded shaft 12a extending through an opening in the plate '18 and .the bore '20 of "the respective bar and threading into the rim 21 positioned at the other end of the bar 12. Supports 21:! are peripherally arthe outer edge. The screen bars 13a are mounted on the outer edges of the .plate 18 and rim "21 to form the screen 13. The rim is. thus securely held to the plate 18 by the bolts 12a, supports 21a and bars 13a. The

.rirn has anlinner circular edge 22 forming 'a circula'ropen- 'ing with the circular lining on the rotor '16. "The 'bars .have a diameter 'D and the holes or openings '23 are spaced so that the surfaces of the bars are spaced the distance through which material may readily pass to the screen 13 and back into the crushing chamber or zone.

The space E of the bars 12 is smaller than the size of the material entering the crushing zone and larger than the size of the material passed by the screen 13.

The'bars 12 instead of being cylindrical may be shaped to have a hat comminuting surface Q8 facing the hitting surface of 'thehammers 11 on the surfaces or mayhave a convex elliptical surface facing the hammers '11.

The screen bars 13 are secured to the .outer edge of the supporting plate '18 and fiange '21 and uniformly spaced to provide selective rectangular slots '25 there'bctween. The screen bar 13.has a triangular or trapezoidal cross-section .so that the slots '25 are expanding divergently outward. The reduced material passes through the space between the bars and drops onto the screen 13. The material passing between the'breakerbars col- '.lects ont'he screen1'3 and is tumbled and shifted by the rotation of the screen so that the material of the desired size passes through the screen. 'The oversized material is carried'up to the top of the breaker by agrated scoop '26 positioned between a breaker bar and a screen bar and dropped 'into the path of the rotor hammersY'for further fragmentation. The scoop is formed by a row of spaced bars 26a extending between one of the "breaker bars and one of the screen bars and firmly and rigidly :ti-ally even flow of material from the screening zone.

The screen may also -be-made "from screen cloth, woven wire, screening or perforated plates, or any other screening material normally used for screening by wrapping such material around the breaker assembly and securing it thereto.

A casing 27 enclosing the comminuting members has a feed chute 28 for passing material to the rectangular opening 14 in the side of the breaker assembly between the lining 47 of rotor and the rim 21. The crushed material of the proper size passing through the screen 13 drops out of the casing through the discharge chute 31. In order to prevent dust from escaping from the crusher, a port 32 is provided in the casing 27 and is connected by means of the conduit 33 to a dust collector. The dust collector sucks the dust out of the crusher by a reduced pressure.

The breaker means 12 and the screen 13 are rotatably mounted on the shaft 15 which is axially aligned with the shaft 34. The casing 27 has sides 35, 36 extending between the end walls 37 and 38. The end walls are supported by pillars 39 and 40 which are securely ernbedded in a concrete base 41. The side walls 36 extend above the end walls 37 and 38 and have an upper semicircular edge 42, 43. The top of the casing has covers 44, 45 pivotally mounted to the top edge of the end walls 37, 38 for opening the top of the casing to inspect the comminuting members and sealing the casing by resting on the edges 42, 43. The rectangular opening 14 is provided in the wall 36 to permit the passage of material from the feed chute 28 into the comminuting members in the casing 27. The opening 14 is positioned intermediately between the end walls 37, 38 and above the hammer circle subscribed by the rotating hammers 11 and the breaker bars 12. The port 32 is formed in the upper portion of the wall 35. The wall 36 is provided with wear-resistant lining plates 46a, 46b, 46c, and 46d. All the plates together form a circle and fit in the opening 30 formed by the rim 21. A mechanical seal is mounted around rotor shaft 34. The upper plates 46c and 46d are formed to fit around the opening 29 in the wall 36 to pass the material into the crusher.

The shaft 34 and rotor 10 are supported by bearings 49 and 50 and are connected through coupling 51 to a motor 16. The rotor and bars are mounted'on a frame 52 slidably mounted on a pair offixed runners 53 secured to the base 41. Thus, the rotor 10 and the resistant plate 47 may be conveniently withdrawn from the crusher for inspection and replacement of worn hammers or parts. The frame 52 is located in position on the stationary runners 53 by bolts 54 fitting through bosses 55 and nut 56 on the frame and runners, respectively.

The shaft or trunnion 15 has flanges 57, 58 between which the bearing 59 is positioned. The bearing 59 supports the shaft 15 in axial alignment with the rotor shaft 34, and the flanges 57, 58 restrict the axial movement of the shaft 15 to a minimum. The bearing 59 has flanges 60 and 61 engaging the flanges 57, 58 on the shaft 15. The shaft 15 is turned by means of a gear 62 and a worm 63. The gear 62 is bolted to the flange 64 which is rigidly secured to the end of the shaft 15. The

worm 63 is driven by an electric motor or other suitable power source (not shown) by means of shaft 65. The bearing 59 and gear 62 and worm 63 are sealed in the casing 66. A supply of oil is introduced into the casing 66 through the spout 67 immersing the worm and lower teeth of the gear 62 in a bath of lubricating oil. The gear 62 carries one or more cups 68 adjacent the peripheral edge thereof to pick up oil from the reservoir in the bottom of the casing 66 and carry it to the upper position for supplying the oil guide 69. The oil guide 69 distributes the oil over the bearing 59 to lubricate the surfaces between the flanges 57 and 60 and 58 and 61, and the surfaces of the shaft 15 and the bearing 59. An oil seal 70 is provided on the shaft 15 in the casing wall 35 to exclude dust and other abrasive material from spacing E may be.

entering the chamber. The bearing 59 is mounted on the base 71 which is in turn supported by the base 41. Thus, the shafts 15, 34 are held from axial movement and in axial alignment during operation. The breaker means 12 is rotated slowly by means of the gear 62 and worm 63. The rotor 10 is turned at a high rate of speed, S

The rotor may have pivoted hammers as shown in Fig. 4 and the fixed hammer may have striking surfaces back to back so that the rotor may be reversed in direction. The breaker bars 12 and the rotor 10 are preferably driven in the same direction with the rotor 10 turning at a high speed. The breaker bars 12 are rotated at a substantially slower speed SL to carry the oversize material to the top of the crushing zone. The rotor 10 and the breaker bars 12 may be rotated in the same direction S or in opposite directions. It is preferable to reverse the relation of the direction of rotation by reversing the direction of rotation of the rotor 10 so that it will not be necessary tochange the angle of the scoop 26.

The breaker bars 12 have been described and illustrated as having circular breaker surfaces. The bars may be rectangular in shape with flat striking surfaces. Also, instead of a single row of breaker bars, a double row of breaker bars 96 and 99 may be provided with the spaces between the bars being of a sufficient width to pass material having a size of the entering material. The material may be picked up by the scoop or scoops in the screening zone and dropped back through the spaces into the rotor. The material hit by the hammers passes between the bars of the first row and strikes the second row of bars.

The material that is initially hit by the hammers against the breaker means may, in the embodiment described and illustrated, either pass between the bars after reduction into the screening zone and be carried up to the top of the crusher from where it may be dropped into the rotor again or the oversized material, instead of passing through the bars, may collect in the bottom of the breaker means and be tumbled therein accumulating until there is a suflicient amount so that the hammers engage the material tumbling on top of this accumulated pile. The hammers will strike these top pieces to further reduce them. The breaker bars may carry some of the pieces between them over the top of the crushing zone and drop the pieces into the rotor.

This material tumbling in the bottom of the breaker I means assists in keeping the breaker bars clean when wet sticky material is fed to the crusher. The continual rotation of the breaker bars and the rubbing of the bars by the accumulated material maintains the bars substantially free of foreign matter so that the impact surfaces remain hard. In comminuting wet material the classifying screen 16 may be dispensed with and the material directly discharged from the breaker means.

The spacing B will depend upon the speed of rotation of the breaker means 12 and the speed of rotation of the hammers 11. The greater the speed, the wider the The diameter of the rotor 10 and the distance B will depend upon the material to be crushed, the speed of rotation of the rotor 10, the size of the entering material and the size of the material finally passing through the screen 13.

Another embodiment of the invention is shown in Fig. 5 in which the screen 13 is replaced by a solid plate 77 thereby retaining the material within the rotating members. The frangible material is introduced into the crusher in a similar manner to the embodiment of Figs. 1

' and 2. Instead of the material being reduced to a given of air entering through the opening 14 and leaving the I chamber throughiflae'passage' formed layzth'e'mibular trunnion 76. Thenair; ia' drawnwout bypauction means such 8.5.58 fan (not shown), and the particle laden stream passes through a cyclone "separator (not shown) to' clear the of the particlesand cdllectjthem at the fbolttom ofatheasepaTatoltmm. .n. I The 'ifrangible material is' introduce'diinto the tcruSher Q through the :opening '14 and "hit by hammers 111 of ;the

rotor against the'breaker 'means 12; The :lscoops '78 are provided ':to "carry themateriahbetween theilbreaker bars'to above the rotor'and 'reintroducethe material, into the comminuting zone. *The material-is reducedtofine particles and is removed by'rsuctionnneans through the discharge outlet 75 trunnion'76. 1 a

The trunnion 76 is tubular "in shape and has cylindrical'wall 80 "forming'the discharge passage 79-= d and the discharge passage .in the has anouter surface 81 forming a journal fittingin the bar 82; A helical conveyor 86 is mounted on the wall 80 and rotates to return oversized material entering the passage 79 to the'comminuting zone. Recessedin the passage 79 from the discharge opening 75 is an impact plate 83 supported by spaced struts 84 to provide openings 85 through which the pulverized material passes. Oversized material projected into the passage 79 hits the impact plateand drops onto the surface 80 to be returned by the conveyor 86. The outer end of the trunnion 76 is coupled to a conduit 87 by means of the flanges 88 and 89 and bolts 90. The conduit 87 is connected to the suction means (not shown). The bearing 82 is similar to the bearing 59 shown in Fig; 1, and a gear 92 is similar to the gear 62 which is securely fastened to the trunnion 76. A worm 93 similar to the worm 63 engages the gear 92 to rotate the trunnion 76 and the breaker means 12. The casing 94 encloses the bearing driving means is adaptedfor rotating saidrotor in.,one'

direction .and said second driving @means isadapted for rotating said breaker means and said 'classify'ing'screen in the opposite direction. I s I r 4. A crusher compris inga'rotor r'1vith*driving" means for turning said "rotorand -having hammers for'fracturing and hitting frangible material against breaker means spaced from said rotor, second driving means having a 82 and the gear 92 and worm 93. Dust seals 95 and 96 are provided at each end of the trunnion 76 to seal the chamber enclosed by thecasing 94. The breaker means 12 are similarly mounted to the circular supporting: plate 18 shown in Fig. l and described in connection therewith. The circular drum-shaped means may comprise a plurality of plates bolted to the supporting plate 18 and the flange or rim 21. The rotor 10 is mounted in a similar manner on the shaft 94 supported by'bearings 49 and 50, and rotated by a motor or other means (not shown).

The material is carried in the bars 12 and the circumferential plate 77 in a similar manner as the bars 12;a nd screen 13 in the embodiment of Fig. l. The material is reintroduced through the spaces 17 until the material is fragmentized to be carried'by the moving air stream.

Various modifications and changes may be made in the crusher without departing from the invention as set forth in the appended claims.

I claim:

1. A crusher comprising ,a rotor with driving means for turning said rotor and having hammers for fracturing and hitting frangible material against breaker means spaced from said rotor, second driving means',.rotatable means for coupling said classifying screen to said second driving means rotating said classifying screen about said rotor, and material return means secured to said classifying screen in said chamber to rotate therewith about said rotor for carrying oversize pieces above the center of radially extending supporting member integral therewith,

breaker means mounted on said radially extending supporting means and having longitudinally extending breaker bars encircling said rotor to rotate with said second driving means and to receive the impact of the material projected 'by said rotating hammers and reduce the material to a given size, said bars being circumferentially spaced to pass the material outwardly through the bars for classification and discharge and to return the oversize material to said bars for further reduction, a classifying screen means encircling said breaker means and spaced therefrom to form 'a classifying chamber to discharge properly sized material from said chamber, said screen means being secured to said radially supporting means to rotate with said breaker bars, and material return means secured to said screen means and said breaker bars to rotate therewith about said rotor for carrying oversize pieces above the center of rotation of said rotor and dropping the pieces through the breaker bars into the path of said hammers for further reduction by the impact of the material with said hammers and said breaker means.

5. A crusher comprising a rotor, driving means for turning said rotor and having hammers for fracturing and hitting frangible material against breaker means spaced from said rotor, breaker means and classifying. screen means formed as an integral member, means for rotating said integral member, said rotatable breaker means having longitudinally extending breaker bars encircling said rotor to receive the impact of material projected by said rotating hammers and reduce the material to a given size, said bars being circumferentially spaced to pass the ma terial outwardly through the bars for classification and discharge of the material to return the oversize material through said bars for further reduction, said classifying screen encircling said breaker means and spaced therefrom to form a circumferentially extending classifying chamber for passing the proper size material out of the crusher and retaining the oversize material and having materialreturn means secured to said screen and said breaker bars for carrying said oversize material above the center of rotation of said rotor and dropping the pieces through the breaker bars and into the path of said hammers for further reduction by the impact of said material with said hammers and said breaker means.

6. A crusher as claimed in claim 1 wherein said breaker bars are cylindrical in shape.

7. A crusher as claimed in claim 1 wherein said classifying screen comprises longitudinally extending screen bars spaced to form rectangular slots diverging outwardly.

8. A crusher as claimed in claim 1 wherein a feed opening for introducing material into said crusher is positioned at the side of said crusher above said rotor and, within the periphery of said breaker means.

1 7 9. A crusher as claimed in claim 1 wherein said hammers are pivotally mounted on said rotor and said rotor is turned in either direction.

10. A crusher as claimed in claim 1 wherein said breaker means comprises two concentric rows of cylindrical breaker bars with the bars of the outer row spaced outwardly from the space between two bars of the inner row and each outer bar spaced from said inner adjacent bars a distance for returning the oversize pieces into the path of the rotating hammers.

12. A crusher as claimed in claim 1 wherein said breaker bars have convex elliptical surfaces facing the rotor.

" UNITED STATES PATENTS Whelpley .l June 28, 1870 Searis et al ".Mar. 5, 1889 Coward Aug; 31, 1897 Hess Jan."'19,.1909 Mitchell Sept. 17, 1912 Brainard Nov. 30, 1920 Horton Feb. 22, 1938 Kennedy 4 Aug. 13, 1940 Gordon Jan. 30, 1951 FOREIGN PATENTS V Italy Oct. 7, 1939 Germany June 29, 1927 7 Germany Nov. 5, 1953

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