US2657864A

US2657864A - Means and method of feeding to

Info

Publication number: US2657864A
Authority: US
Publication date: 1953-11-03
Anticipated expiration: 1970-11-03

Description

Nov. 3, 1953 Y H. J. woocK MEANS AND METHOD OF' FEEDING TO IMPACT CRUSHERS Filed Jan. 16, 1950 llllillllll ,IIIIIII rfa/5985977 J. 000656 IN V EN T 0R.

Patented Nov. 3, 1953 MEANS AND-METHODCF FEEDING'TO IMPACT CRUSH-ERS Herbert J. Woock, Alhambra, Calif. Application January 16, 1950,1Serial No. v1-385861 46 Claims.

This invention relates to .an improved means and method of feeding material :to be crushed to an impact crusher andmay be considered pas .an improvement over vthe disclosure ymadein my `copending application Serial No. 68,872, flied- January 3, 1949.

Heretofora-in operating an impact citusherzthe material to be crushed has vgenerally been fed into the path `of the striking faces on the rotor of the crusher in a more or lless continuous, .steady stream, the intention -being to have the striking faces cut 01T successive increments ofthe stream and by impactcr-ush 4or pulverize the material. In such procedures a portion of the streammay be positioned opposite the center of the striking -face at the instant of impact but succeeding rocks will be encountered by .the striking face near its edge so that there willbe glancingor foul blows. When such Lfoul blows are struck, -not only are the edges of the impact shoes .on the rotor severelydamaged but .the crushing is imperfectly performed so that a substantial amount of thefmater-ial-that is fed :to the rotor must be re-run through the crusher. It isdesirable to feed the material to the rotor ofthe impact crusher in such a manner :that--all-,of-the material at the instant of impact .wil-l be opposite the face of the impact shoes. In this manner severe wear of the impact shoes is-avoided and -as each piece of material .that is to be..crushed is squarely struck a crushing with maximum-.eilicienc-y is obtainable.

In -my copending application there-,is disclosed one method of separating the material vto be crushed into-spaced or isolated bunches which --are consecutively thrown' in timed relationto the rotor into the path ofthe impact -i-shoes. yIn that application a vbucket conveyor `#isernployed wherein each bucketthrowsits contents into the path of the impact shoes in-timed rela.

tion thereto. Such an arrangement, xwhile satisfactory at relatively -low speeds, is --not adequate -where the rotor is traveling at extremely high -speeds wherein the speed oan-impact shoeemay 'be in the neighborhood of as yhigh as-ZOOO-rfeet` per minute. In many instances it is-desirable to drive the rotor of the impact-Crusher -at these extremely high speeds in order to secure the `maximum Apulveriving or crushing effect. However, -when the -rotor is traveling at such speed-f 'the time interval when successive hammers-or iimpact shoes passing the'point of ingress of fthe :material to be crushed, becomes extremelyfsm'all. The :present invention has for its object the provision of al-method and means-'for feedngthe material to be crushed 4into the path of ethe hammers or'impact shoes in the form of :spaced lbunchesorclusters which ca-n be thrown into the pathof the? hammers orimpact shoes .at the rnecessary velocity-to .reach an impact .position between consecutive-.hammers and whereineach ,bunch or cluster'ean reach a substantially-zeentered position with relation to the hammer so as tobe-squarely struck thereby without strag- Aglers encountering the edges of thehammers-or Aimpact shoes thus having foul blows.

-With the foregoing .and .other objects in view, which .will be made manifest inthe following detailed description-and specicallyfpointed out in the appended claims, reference Ais had to the l`accompanying drawingfor an illustrative embodiment ofthe invention, wherein the gure 'is a schematic sectional vView through an 'impact vcrusher and the feed therefor embodying the present invention.

.Referring to the accompanyingv drawings wherein similar reference characters designate similar ,parts throughout, the impact crusher shown consists .of a rotor i0 .on a shaft |.I driven the-direction indicated and carrying one or ymore-hammers or'impact shoes I2. lThese hamfmers or 'impact kshoes yare shown as being arranged ,on tdiametrically opposite sides of .the -rotor so that the rotor will be balanced although the number and yarrangement of 4,the 'hammers can-be varied. A striking plate I3 is arranged adjacent :the rotor and-is adapted to have the --material that v:is struck -by the hammers thrown --thereagainst The Acrushed -material finds egress A'from the `housing |14 that encloses the .impact .fcrusher 4through an' outlet l5.

The -feedlembodying the present invention consists -of`-a conveyor belt 1.6 which carries the -rockor other material .that is to bey crushed, indicated .at .IL-toa hopper t8 intotwhich it is .fdischarged. 7l'Ihe rock :may be-fed into the hopper -f in any vother `suitable manner. although it is preferable to Ifeeditto ithe hopper at a =substantially uniform rate. J-Below the hopper there fis disposed .a -dividi-ng "drum, generally indicated :at fil-Spandf-:which-is yrotatable on a-shaft 20. Ihis `.,mviding-drum yhas l.a series .of pockets 21 `formed on-its .periphery .each of which,` during the. rota- -tion :of the drum,A is-.adapted to receive /affsmall -quantit-yfor group ofthe rocks H that are tou-be fcrus'hed, consecutive groups being illustrated-in -ftwo of the-pockets and indicated at :lflaand 1Mb. An endless'fbelt--Zfis trained overpul-leys -23 `and '24 adjacent f-the periphery of the dividing-drum A--andL-serves to' maintain the Agroups of rock "I 1a and |1b in their respective pockets until it is desired to release or empty a group after it passes the lower pulley 24. The pulleys are urged in spaced relation by means of compression springs to maintain the belt in taut condition and pressed against the periphery of the drum I9. Below the dividing drum there are two spaced

endless belts

26 and 21, the adjacent reaches of which cooperate to define a chute 28 leading down toward the rotor |0. This chute is adapted to have the groups of rock, emptied from the pockets 2|, consecutively dropped therethrough toward the rotor I0. The belt 26 is trained over

pulleys

29 and 30 whereas the belt 21 is trained over pulleys 3| and 32.

Belt tighteners

33 and 34 maintain these belts in taut condition. On the belt 21 there are spaced paddles 35 or gatherers which preferably have resilient facings, such as rubber facings, vulcanized thereto. The housing 36 which encloses the dividing drum I9 and the

belts

26 and 21 and their respective pulleys is adjustably mounted with relation to the housing I4 for vertical adjustment relative to the rotor I0 such as by the adjusting screws 31. When the housing 36 is raised or lowered with relation to the rotor I0 all of the contained structure is adjusted with relation to the rotor I0 therewith.

The mode of operation is substantially as follows: The rock I1 that is to be crushed is fed into the hopper I8 and passes therefrom into the pockets 2| in the divider drum thus being divided into spaced or isiolated groups |1a and I1b. A brush or wiper 38 may wipe off any rock that tends to become between the pockets and pass it into the next succeeding pocket 2|. When a pocket with its contained group of rock, indicated at |117I passes beyond the lower pulley 24, this rock will fall by gravity from the pocket into the chute 28. In so doing the group of rock will tend to string out in the chute, that is, those rocks of the group |1b that are first released from the pocket will be immediately accelerated by gravity in a downward direction. Rocks of the group |1b that are subsequently released from the pocket will also be immediately accelerated by gravity but the commencement of their acceleration will be at a later instant of time. Consequently there will be some Stringing out of the group in the chute 2B 5 whereafter it is desired that the group be gathered into a compact bunch or cluster and caused to enter the path of the hammers I2 at high velocity and in such compact condition. The paddles on the velocity and one of these paddles immediately follows the descending group of rock in the chute 28. The velocity of the following paddles 35 is higher than the velocity attained by the descending strung-out group of rock in the course of its short descent through the chute 28. Consequently, during the fall of the group of rock the paddle 35 will catch up with the stragglers and quickly bring up the stragglers to the velocity of the paddle. The velocity of the paddle is such as to bring up all trailing rock to or above the velocity attained by the leaders that were first emptied from the pocket 2|. The paddle 35 having thus gathered or bunched the rock into a cluster of course continues in its downward direction at the same constant velocity but the rock, having been brought to this velocity, is still subject to the same accelerating effect of gravity and consequently the bunch or cluster will drop or fall away from the paddle 35 and enter thepath of deposited on the divisions belt 21 are driven at relatively high the hammers I2 at a high velocity and 1n a hunched condition. The bunch or cluster can be thus centered with relation to the on-coming hammer or impact shoe so that the entire bunch or cluster will be given a square blow and thrown violently in the direction of the breaker plate I3.

While in impact crushers of this type it would be possible to deliver a bunch or cluster of rock for impact by each hammerl I prefer to alternate or stagger the hits of the hammers on the rotor. Thus in a typical operation of the present feed I will have only every nfth hammer passing below the bottom of the chute 28 make a hit. In conforming to such practice the rotor I!! is rotated at high speed and after one hit has been made with one hammer four succeeding hammers will pass the bottom of the chute 28 without making a hit. The fth succeeding hammer passing beneath the chutes will then make the next succeeding hit on a descending bunch or cluster of rock. With this arrangement the engineering design of a feed for impact crushers embodying the present invention can be highly simplified. Thus, if the length of the belt 21 is three times the circumference of the pulleys 3| and 32 so that there are three paddles 35 equally spaced along the length of the belt, one paddle 35 will have to descend in the chute 28 for each two and onehalf revolutions of the rotor I0 and the pulleys 3| and 32 will have to make one revolution for each two and one-half revolutions of the rotor I0. The speed ratio between th pulleys 3| and 32 and the rotor I0 under these circumstances would have to be 2 to 5, that is, for every revolution of the pulleys 3| and 32 the rotor I0 would have to make two and one-half revolutions. The drum I9, having four pockets, would make one-fourth of a revolution for each revolution of the pulley 3| so that the speed ratio between the shaft 20 and the pulley 3| will be 1 to 4. Any type of drive that will maintain such speed ratios between the rotor |0, the pulleys for the belt 21 and the divider drum I9 may be employed. As typical, however, I have shown chain and sprocket drives between these elements for maintaining such speed ratios it being understood that the chain tightener for the chain between the rotor I0 and the pulley 32 adjusts itself whenever the upper housing 36 is adjusted by the adjustment 31 with relation to the lower housing. This adjustment at 31 permits the entire feed to be adjusted up and down with relation to the rotor I0 so that the bunch or cluster may be accurately centered with relation to the hammer at the instant of impact. The centering of the bunch or cluster does not necessarily have to be at the exact center of the hammer but it should be so arranged with relation to the hammer that all rocks of the bunch or cluster will be given a square blow by the hammer and foul blows eliminated. The exact location of the paddles 35 on the belt 21 is determined by calculation so that these paddles will follow an emptied group of rock and bring up the velocity of the stragglers to the velocity of the leaders in the course of the descent through the chute 28.

From the above described method and apparatus it will be appreciated that the improved feed for impact crushers is highly advantageous in that it first divides the material to be crushed into groups which are consecutively dropped into the chute 28 formed by the

belts

26 and 21. The dropping of the group necessarily involves some Stringing out of the group in the course of its fall through the chute. However, this strungout group is gathered by the paddles 35 in the course of its descent and brought together into a bunch or cluster having the velocity of the paddle 35. When the bunch or cluster is thus gathered and brought to this velocity accelerated downwardly by the force of gravity but remains in its bunched or collected condition. Although the rotor I may be rotating at very high speed the velocity at which the bunch or cluster can be thrown into the hammer path is adequate to position the bunch or cluster in the path of a succeeding hammer even though the time interval between two consecutive hammers is extremely short. As the bunch or cluster is thus delivered to the hammer path in a, compact or clustered condition, an opportunity is afforded to hit the rocks of the bunch or cluster squarely without foul blows which would be present if there were stragglers.

Various changes may be made in the details of the construction without departing from the spirit and scope of the invention as dened by the appended claims.

I claim:

1. The method of feeding material to be crushed into a rotary impact crusher which consists of allowing the material to freely fall towards the crusher, then gathering the material into a bunch or cluster in the course of its fall, and then allowing the bunch or cluster to continue to fall toward the impact crusher.

2. The method of feeding material to be crushed into a rotary impact crusher which consists of dividing the material to be crushed into separated groups, allowing the groups to freely g fall toward the crusher consecutively in timed relation to the crusher, gathering each group into a bunch or cluster in the course of its fall and bringing it up to a predetermined velocity towards the crusher and then allowing the bunched material to fall in bunched condition toward the crusher.

3. An impact crusher comprising a rotary crusher having one or more hammers thereon, means for dividing the material to be crushed into groups and allowing the groups to consecutively freely fall towards the crusher in timed relation thereto, and means for gathering the groups of material in the course of their falls toward the crusher into bunches or clusters and then allowing them to continue their free falls towards the crusher in timed relation thereto.

4. An impact crusher comprising a rotary crusher having one or more hammers thereon, opposed endless belts forming a chute leading downwardly toward the crusher, one of said belts having paddles thereon and being driven in timed relation to the crusher, and means for delivering the material to be crushed so as to fall freely between the belts in spaced groups so that the groups in the course of their fall may be picked up by the paddles and compacted into bunches or clusters and brought to a predetermined velocity toward the crusher.

5. An impact crusher comprising a rotary crusher having one or more hammers thereon, a pair of opposed endless belts providing a chute leading toward the crusher, one of the belts having paddles thereon and being driven in timed relation to the crusher, a divider drum having pockets arranged over the chute, means for supplying material to be crushed to the divider drum to be divided into groups in the pockets thereon, and means for rotating the divider drum in timed relation to the crusher, the divider drum being arranged to empty its pockets over the chute so that the contents of the pockets may fall freely through the chute.

6. An impact crusher comprising a rotary crusher having one or more hammers thereon, a pair of opposed endless belts providing a chute leading toward the crusher, one of the belts having paddles thereon and being driven in timed relation to the crusher, a divider drum having pockets arranged over the chute, means for supplying material to be crushed to the divider drum to be divided into groups in the pockets thereon. and means for rotating the divider drum in timed relation to the crusher, the divider drum being arranged to empty its pockets over the chute so that the material emptied therefrom may fall freely through the chute, the belts and divider drum being vertically adjustable with relation to the crusher.

HERBERT J. WOOCK.

References Cited in the file of this patent UNITED STATES PATENTS