US3452938A

US3452938A - Jaw-type crusher

Info

Publication number: US3452938A
Application number: US458071A
Authority: US
Inventors: Stanley D Michaelson
Original assignee: Kennecott Copper Corp
Current assignee: Kennecott Corp
Priority date: 1965-05-24
Filing date: 1965-05-24
Publication date: 1969-07-01
Anticipated expiration: 1986-07-01
Also published as: NO122216B; FI47283B; GB1119154A; FI47283C; DE1507767B; IL25815A; ES327611A1; CH456315A; SE347879B

Description

y 1969 s. D. MICHAELSON JAW-TYPE CRUSHER Sheet of3 Filed May 24, 1965 F/G Z.

INVENTOR. STANLEY D. MICHAELSON AT TORNE YS July 1, 1969 s. D. MICHAELSON JAW-TYPE CRUSHER Filed May 24, 1965 INVENTOR. STANLEY D MICHAELSON BY M M ATTORNEYS United States Patent US. Cl. 241-202 19 Claims ABSTRACT OF THE DISCLOSURE A jaw-type crusher having jaws mounted on axes that are substantially vertical to define therebetween a crushing chamber having feed and discharge openings at op posite ends and an open bottom for the discharge of material as it is crushed. The bottom of the crushing chamber is partially closed by material supporting and screening means, so that material to be crushed travels along such partially closed bottom and crushed fines are sized and fall from the crushing chamber substantially as they are formed and have no opportunity to choke the discharge opening at the discharge end of the chamber. The jaws and their axes can be inclined from the vertical within the meaning of the term substantially vertical, so long as there is sizing and gravity discharge of most of the crushed fines by and through the partially closed bottom.

This invention relates to jaw-type crushers for use in effecting size reduction or comminution of ore, rock, and other materials and is particularly concerned with providing a jaw-type crusher capable of at least, and usually greater than, the normal throughput and performance, without requiring the head room or the massive and relatively costly foundations and/or supporting structures needed by other crushers of jaw type currently in common use.

Conventional jaw crushers are provided with at least one movable jaw that is suspended from a horizontal shaft and is usually eccentrically mounted. The jaw oscillates or reciprocates about a horizontal axis and, together with a fixed jaw or another movable jaw, provides a downwardly convergent, crushing chamber. The material to be crushed is introduced into the wide upper end of such chamber and emerges from the relatively narrow lower end, passing through the chamber by the force of gravity while being crushed by the oscillating or reciprocating action of the one jaw relative to the other or of both jaws relative to each other. The gape, i.e. width, of the relatively narrow discharge opening at the lower end of the chamber and the frequency and amplitude of the motion of the jaw or jaws govern the amount of material that can be crushed and its size after crushing. If the material is to be finely crushed, the crushing chamber must be long and the discharge opening therefrom small in comparison to what is permissible for coarse crushing.

The jaws and other parts of the crusher, which are subject to impact and abrasion or other wear from the material to be crushed, are usually protected by replaceable castings, fabrications, curved or straight jaw plates, side plates, sheets and the like.

A high clearance (headroom) is required for the placement of a conventional jaw crusher, to allow the jaws to be vertically mounted or inclined steeply with respect to horizontal axes and to provide space for the necessary structure used for feeding material to and carrying it away from the jaws. In some situations, for example underground mining operations, the necessary headroom is not ordinarily available or economically practical to Patented July 1, 1969 obtain. Thus, in the past, it has not normally been practical to use jaw-type crushers at such places as the bottoms of shafts and stopes or in drifts and other passageways or rooms in underground mines, even though this would be highly desirable.

In addition, a conventional jaw crusher has a tendency to become choked when fed at or near its maximum capacity. It also has a tendency to become choked in most fine-crushing applications, even under the best of conditions, because of the convergent nature of the crushing chamber from feed end to discharge end thereof. Also, with most materials to be crushed, the throughput capacity of an ordinary jaw crusher is considerably limited by reason of the accumulation of fines as the material is progressively crushed in its passage through the chamber be tween the jaws.

Principal objects of the present invention are, therefore, to provide a jaw crusher that can be placed and can satisfactorily operate within a restricted area so far as headroom is concerned; one that does not require an excessively heavy foundation or supporting base; and one that substantially eliminates the problem of choking.

For the accomplishment of these objects in accordance with this invention, the jaws of the crusher are mounted on substantially vertical axes so the relatively wide feed opening and the relatively narrow discharge opening of the crushing chamber between the jaws, which openings in the usual jaw-type crusher are horizontally disposed, are here substantially vertically disposed, with the longitudinal openings of such crushing chamber being substantially horizontally disposed and open at the top and the bottom of the crushing chamber, instead of vertically disposed laterally of the chamber and closed by vertical members as in the usual type of jaw crusher. As so arranged, the bottom of the crushing chamber is essentially open and converges from the feed end to the discharge end thereof, as does the chamber itself.

In accordance with the invention, this bottom opening is provided with material-supporting means which partially close it and serve as a screen for passing from the chamber by gravity such fines as may be introduced with the feed material and also a good part of the fines produced by the crushing operation as the material travels along the length of the chamber. This effectively eliminates much of the feed material before it reaches the relatively narrow discharge opening of the crushing chamber and greatly minimizes, if not entirely eliminates, the usual problem of choking.

By selecting a material-supporting means of desired material-throughput size and capacity, desired sizing of fines passing from the crushing chamber by gravity discharge in advance of the relatively narrow opening at the discharge end of the crusher can be attained.

Also in accordance with the invention, there is preferably provided means for forcing the material to travel longitudinally along and through the crushing chamber although it is realized that in some instances the crusher can be sloped downwardly so all material travel and discharge can be either effected or aided by gravity.

The material-supporting means may be and preferably is in most instances an elongate and tapered platform converging from feed end to discharge end of the crushing chamber, but being narrower in width than the open bottom of such chamber and being centrally located between the crushing jaws, all in accordance with desired screening characteristics.

Such platform is preferably reciprocatable and transversely stepped in formation along its length and in the direction of material travel through the crushing chamber, so as to itself function as the means for feeding such material through the crushing chamber. Advantageously, there is a hopper for feeding the material to be crushed onto a platform section in advance of the feed opening of the crushing chamber, and, desirably, particularly for the smaller size crushers, the hopper itself is reciprocatable and the platform is rigidly attached to such hopper for simultaneous reciprocation therewith. If the aforesaid platform section is fabricated as a grizzly or other type of screen, desirable advance screening of the feed material is effected.

When more than one movable jaw is provided, a single power unit can be employed to drive such movable jaws, or separate, preferably synchronized power units can be employed. With either arrangement and also when one of the jaws is stationary, maximum effectiveness is obtained when the reciprocating means is synchronized with the crushing action of the jaws such that a forward thrust will move the material being crushed into and through the crushing chamber at the same time the jaws are being moved apart to the maximum opening. Excellent results can also be obtained by conveying the material into and through the crushing chamber at high speed. This tends to crowd and push the material into and through the chamber. However, for many applications of this invention, it is not essential that such synchronization or high conveying rate of the reciprocating means be employed.

There are shown in the accompanying drawings specific embodiments of the invention illustrating what are presently regarded as the best modes of carrying out the generic concepts in actual practice. From the detailed description of these presently preferred forms of the invention, other more specific objects and features will become apparent.

In the drawings:

FIG. 1 is a top plan view of one form of the jaw crusher of the invention;

FIG. 2, a side elevation;

FIG. 3, a vertical section taken on the line 33 of FIG. 1;

FIG. 4, a horizontal section taken on the line 4-4 of FIG. 2;

FIG. 5, an end elevation;

FIG. 6, a top plan view of a somewhat different embodiment of the invention;

FIG. 7, a fragmentary vertical section taken on the line 77 of FIG. 6 to show the different form of materialsupporting structure used for this embodiment of the invention;

FIGS. 8, 9, and 10, views corresponding to FIG. 7, but showing other forms of the material supporting structure.

Referring now to the drawings:

In the embodiment illustrated in FIGS. 1-5, the crusher includes a pair of movable, convergent, crushing

jaws

11 and 12 and a feed hopper 13, all supported on a frame 14. Although, as shown, the jaws include straight plates 11a and 12a at their working faces, curved plates could be used as well. Also, feed hopper 13 could be mounted on a separate frame, if desired.

In accordance with the invention, the crushing

jaws

11 and 12 of this embodiment are mounted on vertical axes, as contrasted with the mounting of the jaws of a conventional jaw crusher on horizontal axes. As so mounted,

such jaws

11 and 12 define a relatively wide and vertically disposed material-feed opening A, FIG. 4, at the set of ends facing the feed hopper 13; a relatively narrow and vertically disposed, material-discharge opening B at the opposite set of ends remote from the feed hopper; and convergent, longitudinal openings horizontally disposed at top and bottom of the crushing chamber C formed between the jaws.

The convergent, longitudinal, bottom opening D serves the very important function of discharging fines from the crushing chamber C as the material moves longitudinally therethrough from feed opening A to discharge opening B. For this purpose it is provided with material supporting means to be hereinafter described, which, in effect serves a screening function, permitting only the fines to progressively discharge and retaining the relatively coarse material for continued exposure to the crushing action of the jaws, and which is also advantageously motivated to force travel of the feed material from feed end A to discharge end B of the crushing chamber.

Mounting of the crushing jaws on vertical axes, as in this illustrated embodiment, requires the least headroom for the crusher and takes maximum advantage of the force of gravity for the screening function. Nevertheless, minimum headroom may not always be a factor or the most important factor. It may be desirable to utilize the force of gravity to cause some or even all the travel of the feed material from feed end to discharge end of the crushing chamber. Thus, the term substantially vertical," as used to describe the mounting axes of the jaws is intended to include rather wide deviations from the true vertical, so long as the force of gravity is operable to pass fines from the crushing chamber through the longitudinal bottom opening thereof during travel of the feed material from the feed end to the discharge end of the chamber.

Crushing

jaws

11 and 12 are eccentrically driven. For this purpose, they are rotatably mounted at corresponding ends on

eccentrics

15 and 16, respectively, FIG. 4, which are fixed on shafts l7 and 18. Each of such shafts is journaled and supported by a set of

bearings

19 and 20, FIG. 2. Drive

sprockets

21 and 22 are fixed to shafts 17 and 18, respectively, and are driven simultaneously in opposite directions by any suitable drive arrangement, for example the one shown which is described hereinafter.

The other ends of

jaws

11 and 12 are provided with grooves 23, FIG. 4, which each receive an end of one of a pair of toggles 24 as a pivot. The other ends of the toggles are positioned as pivots in similar grooves 25 formed in support blocks 26 that are carried by frame 14.

Springs 27, FIG. 1, anchored to frame 14 by bolts 28 and anchored to the respective jaws by bolts 29, bias the jaws into constant engagement with their respective toggles, so that rotation of the eccentrically mounted ends of the jaw results in a rocking motion of the toggles and of the ends of the jaws in engagement therewith and in an elliptical motion of such jaws at their eccentrically mounted ends.

Sprockets

21 and 22 are driven by a motor 30, through a drive arrangement that includes

pulleys

31 and 32, belt 33, countershaft and sprocket 34, FIG. 2, endless chain 36, and idler sprocket 37, FIG. 1. Operation of the motor drives chain 36 to rotate sprocket 21 counterclockwise and sprocket 22 clockwise so that the jaws move toward and away from each other synchronously, with a longitudinal component toward the discharge opening B when the jaws are moving toward each other, which tends to push the feed material toward and through such discharge opening.

Jaws

11 and 12 are respectively cantilevered outwardly from

eccentrics

15 and 16 and are further supported by toggles 23 and springs 27.

Flanges

38 and 39 extend outwardly from the jaws above and below the toggles to prevent the ends of the jaws dropping away from the toggles. It is apparent that additional frame structure can be built near to and above or below the ends of the jaws if deemed desirable, and that suspension or flexible compressive means, such as springs, hydraulic supports, or resilient shear mountings, can be employed to assist in the support of the jaws whenever additional support is required. In the case of small machines or of larger machines of light construction operating on soft material, such additional support will not generally be necessary.

Material to be crushed is charged into hopper 13 in any convenient manner, and, by reason of reciprocating motion applied to such hopper, is passed through hopperdischarge opening 40, FIG. 3, onto a platform extension 41 of the hopper bottom, which may be an imperforate plate or a screen of some kind, such as the illustrated grizzly, or a combination of both, closed laterally by extensions 42 of the side walls of the hopper. Material small enough to fall through the openings of the grizzly drops to a chute 43 for transfer to a collection pile or to a conveyance, such as an ore car or truck. Where headroom is a problem, the chute can be replaced by a conveyor passed directly underneath the grizzly.

The coarser material that does not pass through the grizzly is fed into the crushing chamber C between

jaws

11 and 12 by way of feed opening A. To facilitate discharge of the fines before the material is passed into the crushing chamber, the bars of the grizzly should either be parallel or diverge slightly as they extend toward the crushing chamber. Ordinarily, they should not converge.

In the illustrated embodiment, the material-supporting means partially closing the longitudinal bottom opening D of the crushing chamber is an elongate platform member 44, FIGS. 1 and 4, fixed to and projecting forwardly from grizzly 41 to define relatively narrow, elongate, screening openings D and D Being rigid with reciprocating hopper 13, this platform member also serves as means for feeding or at least for aiding passage of the coarser material through the crushing chamber, where it is exposed to the crushing action of the

jaws

11 and 12. For this purpose, material-supporting platform member 44, FIG. 1, is preferably transversely stepped along its length, as at 44a, b, c, and d, with the individual steps being inclined upwardly, see FIG. 3, to better force the material along.

For reciprocating the hopper and its forwardly-extending

platform members

41 and 44, drive means are provided in the form of a motor 50, FIGS. 3 and 4, connected by belt 51, pulleys 52 and 53, and a crank 54 to one end of a drive rod 55. The opposite end of such drive rod 55 is pivotally attached to a shaft 56, FIG. 4, which is rigidly secured to rearward extensions 41a of individual grizzly bars that extend back under the bottom of the hopper and are welded thereto.

Hopper 13 is resiliently supported by frame 14 to permit the reciprocative movement imparted to it by drive rod 55 and to induce a vertical component into such reciprocative movement. For this purpose, the hopper is provided with a rearwardly-extending, rigid frame made up of side members 57 and end member 58, the side members being rigidly connected, as by welding, to depending portions (not shown) of the side walls of the hopper. Suspension springs 59 and 60 serve to connect frame end member 58 with a structural angle 61 interconnecting respective posts 62 that rise rigidly from frame 14, the attachments of such springs to the angle being preferably by means of bolts, as indicated, to permit adjustment in spring tension. A stifliy resilient suspension element 63, FIGS. 3 and 4, such as a piece of resilient material like rubber or rubber conveyor belting, connects frame end member 58 with an intermediate frame member 64 to further support the hopper, and a similar suspension element 65 supports the forward end of stepped platform member 44 directly on frame 14.

The combined weight of the hopper 13 and material supporting means 41 and 44 is further distributed to frame 14 through stub members 66, FIGS. 2 and 4, projecting rigidly from opposite sides of the hopper and resting on coil springs 67 that, in turn, rest on stringers 68 superimposed on frame 14.

It should be noted that the stringers 68 also serve to support the crushing

jaws

11 and 12 by reason of the fact that the lower bearings 20 of the respective sets of

bearings

19, 20 for the shafts 17 and 18 rest directly on such stringers, see FIG. 2, the upper bearings 19 being carried by a bridge 69 having legs 70 resting directly on frame 14. It should also be noted that springs 27 at the forward ends of the jaws are fastened to frame 14 through posts 71 rising from stringers 68.

When hopper 13 is reciprocated, the material passes therefrom and along the platform formed by grizzly 42 and stepped extension 44 much as it would on a shaker conveyor. As has been previously explained, material small enough to fall between the bars of the grizzly drops onto inclined chute 43, from where it slides to an awaiting receiver, such as an ore car, truck, or storage pile or bin. The remainder of the material passes through the crushing chamber C toward the end B thereof and is subjected to the crushing action of

jaws

11 and 12, with fines being discharged progressively through the screening openings D1 and D2- In order to provide greater screening action, the platform extension 44 can also be of grizzly formation, as shown at 72 in the embodiment of FIGS. 6 and 7. It can also be unstepped and of various contours, for example convex as shown at 73 in FIG. 8, with or without a cover plate 74; or concave, as at 75 in FIG. 9; or sloping instead of stepped, as shown for the convex imperforate plate 76 of FIG. 10. A great variety of other formations for the grizzly and platform extension thereof are possible to meet various circumstances.

Separate motors can be used to drive the crushing jaws. Such an arrangement is illustrated in FIG. 6. In this embodiment, motors 77 and 78 have their drive pulleys 79 and 80 connected by

belts

81 and 82 to pulleys 83 and 84 that correspond to the

sprockets

21 and 22 of the embodiment of FIGS. 1-5.

Motors 77 and 78 may be electrically or mechanically timed in conjunction with the drive motor used to reciprocate the material-supporting means such that forward reciprocation of the latter will feed material into the crushing chamber at the same time the crushing jaws are opened to their maximum.

In either the embodiment of FIGS. 1-5 or the embodiment of FIG. 6, a drive motor for the jaws can also be mechanically connected to reciprocate the feed hopper and material supporting means, so that a separate motor is not needed for the latter purpose. Moreover, although the use of a reciprocating hopper is preferred, it may be desirable in some instances to make the hopper stationary, with the material merely sliding onto materialsupporting means constructed as a conveyor to carry the material into and through the crushing chamber. Also, the bottom of the feed hopper may itself be perforated or have elongate openings formed therein to screen out fines in advance of or in place of the grizzly.

The choice of particular constructions and arrangements will depend on a variety of factors, including the hardness, brittleness, friability, moisture content, stickiness, and other characteristics of the material being crushed.

While the invention has been specifically disclosed as utilizing a pair of opposing single-toggle type crushing jaws eccentrically mounted at one set of ends, other conventional crushing jaw arrangements can also be used. Thus, Blake-type or Dodge-type jaws and movements or a pair of movable jaws with a stationary crushing pier or jaw between them as a reaction member can be utilized so long as the jaws are placed as prescribed herein for obtaining combined crushing and screening action.

Whereas there are here illustrated and specifically described certain preferred constructions of apparatus which are presently regarded as the best modes of carrying out the invention, it should be understood that various changes may be made and other constructions adopted without departing from the inventive subject matter particularly pointed out and claimed herebelow.

I claim:

1. A jaw-type crusher, comprising cooperatively opposed crushing jaws mounted on substantially vertical axes as lateral walls of a crushing chamber, said jaws converging from a relatively wide feed opening at one end of said chamber to a relatively narrow discharge opening at the opposite end of said chamber, said chamber having an open bottom that also converges from said feed opening to said discharge opening and provides for gravity discharge of crushed material during travel of material through said chamber, at least one of said jaws being eccentrically mounted for material-crushing movement toward and away from the other jaw; material-supporting and sizing means partially closing said bottom of the crushing chamber to limit the maximum piece size of material that can discharge from said chamber through said open bottom thereof; means supporting said jaws; and means for operating the said at least one of said jaws.

2. A jaw-type crusher according to claim 1, wherein both the jaws are movable in cooperative crushing relationship.

3. A jaw-type crusher according to claim 2, wherein both jaws are operated by the same means.

4. A jaw-type crusher according to claim 2, wherein the jaw-operating means includes separate means for operating respective jaws.

5. A jaw-type crusher according to claim 1, further including means for forcing travel of material longitudinally of the crushing chamber.

6. A jaw-type crusher according to claim 1, further including means for feeding material into and longitudinally through said crushing chamber.

7. A jaw-type crusher according to claim 6, wherein the means for feeding material includes a hopper.

8. A jaw-type crusher according to claim 7, wherein the means for feeding material also includes means for reciprocating the hopper.

9. A jaw-type crusher according to claim 8, wherein the material-supporting means is fixed to and reciprocates with the hopper.

10. A jaw-type crusher according to claim 9, wherein the material-supporting means comprises a tapered platform positioned substantially centrally of the open bottom of the crushing chamber.

11. A jaw-type crusher according to claim 10, wherein at least a portion of the platform is formed as a grizzly.

12. A jaw-type crusher according to claim 11, wherein the platform is of stepped formation along substantially the length of the crushing chamber.

13. A jaw-type crusher according to claim 12, wherein a platform section in advance of the stepped formation is formed as a grizzly.

14. A jaw-type crusher, comprising cooperatively opposed crushing jaws, at least one of which is mounted for movement toward and away from the other, said jaws being positioned and spaced relative to each other to define a crushing chamber therebetween open at its ends for the feed and discharge of material, respectively, and with its bottom downwardly directed, the open ends of said chamber being substantially in horizontal alignment such that material can discharge from said bottom under the influence of gravity; material supporting and screen ing means across the bottom of said chamber for passing relatively fine material and retaining relatively coarse material, and means for operating the said at least one of the jaws.

15. A jaw-type crusher in accordance with claim 14, including means for forcing travel of material within said chamber from the feed end thereof toward the discharge end.

16. A jaw-type crusher in accordance with claim 15, wherein the means for forcing travel of material comprises means for motivating the screening means.

17. A jaw-type crusher, comprising cooperatively opposed crushing jaws; means mounting at least one of said jaws for movement toward and away from the other, said jaws being positioned and spaced relative to each other to define a crushing chamber therebetween open at its ends for the feed and discharge of material, respectively, and open along at least one of its lateral sides; said jaws and said chamber being off-vertical, so that the said open lateral side is directed downwardly as a bottom for said chamber; and material-supporting screening means positioned across said downwardly directed bottom for supporting relatively coarse material within said chamber while permitting relatively fine material to fall therefrom tthrough said screen.

18. A jaw-type crusher according to claim 17, wherein the material-supporting screening means comprises a tapered platform positioned substantially centrally of the open bottom of the crushing chamber, and wherein means are provided for vibrating said platform as a conveyor for forcing travel of material through said crushing chamber toward the discharge end thereof.

19. A jaw-type crusher according to claim 18, wherein the platform is of stepped formation along substantially the length of the crushing chamber.

References Cited UNITED STATES PATENTS 2,999,651 9/1961 Ault 241-218 FOREIGN PATENTS 1,013,248 8/1957 Germany. 1,100,431 2/1961 Germany.

294,972 4/1965 Netherlands. 1,109,986 6/1961 Germany. 1,134,873 8/1962 Germany.

WILLIAM S. LAWSON, Primary Examiner.

US. Cl. X.R. 241-265