US3315901A - Gas hydraulic spring for crushing apparatus - Google Patents

Description

A ril 25, 1967 Original Filed Aug. 51, 1962 ni'n 7 gal/ 6/ 1 aa FIG 3 INVENTOR 2 HAR LD .PoLL/TZ ATTORNEY United States Patent 0 11 Claims. (Cl. 241211) The present invention concerns crushers, of the gymtory and cone types, for instance, 'which incorporate spaced crushing members between which material is crushed by movement of the members with respect to each other, and particularly relates to means for maintaining and adjusting the spacing between the members and for permitting it resiliently to increase should the design load of the crusher be exceeded.

This application is a division of copending application Serial No. 220,697, filed August 31, 1962, now abandoned.

In the case of crushers of the .gyratory type, adjustment of the crushing mantle relative to the bowl is usually achieved by supporting the lower end of the mantle mainshaft upon a hydraulic jack which permits the mantle to be raised toward or lowered away from the bowl. In order to accommodate overloads, such as tramp iron, for instance, the hydraulic circuit of the jack incorporates an accumulator pressurized with gas. hydraulic fluid in the jack becomes greater than that of the gas, owing to the introduction of tramp iron into the crusher, fluid is forced from the jack into the accumulator, thus permitting the mantle to lower in order to increase the space between it and the bowl until the tramp iron is discharged. In the case of crushers of the cone type, on the other hand, adjustment of the cone relative to the bowl is usually accomplished by movement of the bowl itself. Overloads are absorbed by suitably positioned coil spring assemblies compressed between the bowl and the crusher frame, thus permitting the bowl resiliently to rise relative to the cone upon the introduction of tramp iron, for instance.

The use of a hydraulic jack type of suspension in the case of a gyratory crusher for both adjustment and overload protection involves substantial excess equipment besides the jack itself, including a fluid reservoir, an accumulator, and all the necessary connecting piping. Furthermore, the crusher cannot readily be disassembled, or the jack readily replaced, without substantial time being required to disconnect the hydraulic reservoir and accumulator and to drain the jack. Upon reassembly of the crusher, the jack must be refilled with fluid and reconnected into the hydraulic system. Even a simple adjustment of the spacing between the mantle and bowl requires pumping fluid in or out of the jack. In the case of a cone crusher, while adjustment of the spacing between the cone and the bowl is usually achieved by means other than that provided to accommodate overloads, nevertheless much time and eflort is necessarily involved in backing off and/ or turning up the nuts compressing the coil spring overload assemblies around the bowl in order to replace or adjust same. Consequently, crusher shut down time may be lengthy in the event of such replacement or adjustment.

It is toward elmination of the disadvantages outlined. above that the present invention is directed. For this purpose, the hydraulic jack of the gyratory type crusher and the coil spring assemblies of the cone type, as the case may be, are replaced with one or more self-contained gas hydraulic springs. Each of the latter incorporates essentially a hydraulic cylinder pressurized with a suit- When pressure on the able gas which in turn exerts its force upon a main piston and a piston rod. An additional or floating piston may also be incorporated in the cylinder in order to provide for better lubrication and sealing. As: applied to a gyratory type crusher, for instance, one or more such springs, each having a fixed, maximum over-all length when uncompressed and compressible to a lesser length, are simply inserted in place of the usual hydraulic jack so that forces between the crushing bowl and mantle are transmitted by the lower end of the latters shaft to the cylinder and piston rod axially thereof. Simple snub bolts, operative for instance between the end of the assembly remote from the mantles main shaft and the end of the hub of the latter, permit easy and rapid raising or lowering of the mantle to adjust the space between it and the bowl, as well as a means of removing end play between the hydraulic spring assembly and the mantles main shaft. As used herein, the expression design load of the crusher is intended to refer to the load above which damage to the crusher begins to be likely. The design load is thus greater than what may be called the crushing or working load which is imposed upon the crusher during its regular operation. The cylinder is pressured therefore so that it exerts a force on the piston and rod in excess of the crushing or working load, preferably, in fact, equal to the design load of the crusher. Accordingly, when an overload would otherwise occur, that is, when the design load of the crusher would be exceeded, the gas in the cylinder is simply compressed by axial movement of the mantle until the tramp iron or other extraneous matter has been discharged, whereupon the mantle is returned to its original spacing from the bowl. Since the assembly itself exerts no pressure upon the mantles shaft until it is compressed, it is easily disengaged for removal as a self-contained unit, simply by backing off the snub bolts.

Essentially the same unit can be applied to a cone crusher. In that case several hydraulic springs of the present invention are simply inserted in place of the usual coil spring assemblies between the bowl and the frame and also pressurized to exert a total force equal to the design load of the crusher. Snub bolts are also provided which can be turned up against one end of each spring, as in the case of the gyratory crusher. As before, each unit is pressurized so that the total of the forces exerted by all such springs is equal to the design load of the crusher. Accordingly, should an overload occur, the gas in the cylinders is compressed, allowing the spacing between the cone and bowl resiliently to increase and then to return to its original setting after discharge of the extraneous matter. The use of these springs in cone crushers also eliminates the need for any additional overload safety devices, overload protection being achieved instead, simply by providing a suflicient stroke for the piston of each hydraulic spring.

In addition, in the case of the cone crusher, the laborious and lengthy process of turning up or undoing several screw nuts is unnecessary in order to achieve the necessary spring pressure. Instead, such pressure is instantly available as son as the snub bolts are turned up to capture the hydraulic springs firmly between the frame and bowl. Note also that the snub bolts need not be turned up to compress the gas, but only enough to remove any play between the ends of each spring and the seats against which they abut. Each hydraulic spring can be simply and easily installed or removed inasumch as it is not only wholly selfcontained but also has a fixed, maximum length; as in the case of the application to a gyratory crusher, it is not necessary, therefore, to discharge the cylinder in order to release the spring from the crusher.

Accordingly, the primary object of the present invention is the provision of a self-contained gas hydraulic spring for crushers of the types described which permits both the spacing between the crushing members to be easily and quickly adjusted and an overload to be safely absorbed without need of crusher shutdown.

Another object of the present invention is to provide crushers of the types described with self-contained gas hydraulic springs interposed to resist increase in the spacing between the crushing members, each spring incorporating a cylinder filled with gas to a pressure so that the total force exerted by all such cylinders is equal to the design load of the crusher.

A further object of the present invention is the provision of crushers of the kinds described with gas hydraulic springs interposed to resist increase in the spacing between the crushing members, each spring incorporating a piston, a piston rod and a cylinder filled with gas to a pressure so that the total force exerted upon all the piston rods is equal to the design load of the crusher, each spring being self-contained and having a fixed maximum length.

An additional object of the present invention is to provide a self-contained gas hydraulic spring, preferably of fixed maximum length, for crushe-rs of the kinds described, each unit incorporating a cylinder, a main piston and piston rod and a floating piston, the cylinder being capable of being pressurized with gas between one end thereof and the free piston and of being filled with a non-compressible lubricating fluid between the main and floating pistons.

Other and further objects, features and advantages of the present invention will be apparent from the preferred form thereof hereafter described, read in conjunction with the following drawings, in which:

FIGURE 1 is a side view, partly in section, through the axis of one of the gas hydraulic springs utilized in the crushers illustrated in FIGURES 2 and 3;

FIGURE 2 is an elevational view, partly in section of a typical gyratory type crusher illustrating the application thereto of the hydraulic spring illustrated in FIGURE 1; and

FIGURE 3 is an elevational view, partly in section, of a typical cone type crusher illustrating the application thereto of the hydraulic spring shown in FIGURE 1.

Each gas hydraulic spring 30 illustrated in FIGURE 1 incorporates a hollow cylinder 31, closed at one end by end cap 32, and provided with a main piston 33 slidable therein having a piston rod 34 integral therewith extending axially therefrom to beyond the other end of cylinder 31, an O ring 35 providing sealing between cylinder 31 and piston 33. The length of cylinder 31 and the stroke of piston 34 will, of course, depend primarily upon the amount of movement required in order for the crusher safely to absorb any possible overload. The remaining end of cylinder 31 is internally threaded to receive an externally threaded end plug 36 bored axially to slidably receive piston rod 34 therethrough. An annular wiper type seal 37 between rod 34 and plug 36 is provided at the outer end of the bore through the latter. End plug 36 is locked in place by means of a threaded retaining ring 38 turned up tightly thereagainst. Piston 33 and rod 34 are bored axially to provide a passage 39, communicating with the interior of cylinder 31, its outer end being counterbored in turn to receive a removable plug 40 threaded therein well below the outer end of rod 34. A second or floating piston 41 is also provided in cylinder 31 and is slidable therein between end cap 32 and piston 33. Piston 41 has its opposite ends 42, 42 dished and is equipped with an annular, axially extending relief 43 in its outer circumferential wall communicating with the space between pistons 33 and 41 by means of an inclined passageway 44. Sealing between cylinder 31 and piston 41 is accomplished by suitable rings 45 received in a pair of axially spaced, circumferential grooves straddling relief 43. Finally, the wall of cylinder 31 is bored between end cap 32 and piston 41 and provided with a suitable gas charging valve 46. Before use, plugs 40 are removed and the space between pistons 33 and 41 filled through passage 39 with a non-compressible fluid, such as heavy oil. Plugs are then replaced.

The application of the present invention to a gyratory type of crusher, as illustrated in FIGURE 2, is straight forward. The customary hydraulic jack assembly may be simply omitted and in its place in the lower hub between end cap 51 and the lower end of the main shaft 52 of the gyratory crushing mantle 53 is substituted a suitable gas hydraulic spring 30 according to the present invention. A suitable gas, such as nitrogen, is then introduced through valve 46, forcing piston 33 against end plug 36, until the pressure in cylinder is equal to the design load of the crusher. End cap 32 thereof thus bears against the lower end of shaft 52 and a snub bolt 54 is threaded up through end cap 51 to bear against the outer end of piston rod 34. Adjustment of snub bolt 54 will vary the spacing between mantle 53 and bowl 55 thereabove, inasmuch as shaft 52 is vertically movable in its bearings 56 relative thereto.

In the case of the cone type crusher, as illustrated in FIGURE 3, vertical adjustment of the spacing between the crushing bowl 60 and the eccentrically mounted crushing cone 61 is achieved by threaded engagement between the outer periphery of the former and annular seat 62. The outer periphery of the latter in turn has spaced at intervals thereabout a number of outwardly extending lugs 63 which seat upon corresponding lugs 64 therebelow extending outwardly from frame 65. A pair of spaced, vertical tie bolts 66 pass slidably through each pair 'of lugs 63 and 64 and have secured thereto between their lower ends a horizontal platform base 67. Between each pair of tie bolts 66 a gas hydraulic spring 30 according to the present invnetion is interposed between the lower face of each lug 64 and the upper face of the corresponding platform base 67 therebelow, the ends of each piston rod 34 butting against a snub bolt 68 threaded up through platform base 67. Springs 30 are pressurized so that the sum of the forces on each piston 41, and thus on piston rods 34, is equal to the design load of the crusher. Accordingly, an overload is transmitted by bowl 60 to its seat 62, then to tie rods 66 and platform base 67, and finally to lugs 64 on frames through springs 30, compressing the gas therein. Any adjustment of bowl 60 relative to cone 61 can be compensated for by turning snub bolts 68 in or out, as the case may be.

While the present invention has been described with reference to particular embodiments and applications thereof and detailed descriptive language has been used, it is not so limited. Indeed, the invention is also adaptable to other forms of crushers, one such additional adaptation, that to a roll type crusher, being described and claimed in application Ser. No. 444,919, filed March 22, 1965, a continuation of the aforesaid application Ser. No. 220,697. Accordingly, the following claims are to be read as encompassing all modifications and adaptations of the invention falling within the spirit and scope thereof.

I claim:

1. In material crushers including a pair of spaced crushing elements having crushing surfaces and adapted by movement of said elements relative to each other to crush material therebetween, at least one of said elements being movable with respect to the other in order to adjust the spacing between said crushing surfaces, the combination therewith of one or more gas hydraulic means operatively associated with said one of said elements for maintaining a predetermined spacing between said surfaces during their crushing operation up to a predetermined load therebetween and to accommodate an overload by resiliently increasing the spacing between said surfaces, said means comprising at least one piston housing having opposite closed ends, a main piston in said housing slidable between said ends, and a gaseous fluid under pressure between said piston and one of said closed ends, said means being operatively associated with said elements so that thrust between said surfaces is received against the pressure of said fluid, said pressure being such that the total force exerted thereby is sufficient to maintain said predetermined spacing between said surfaces up to said predetermined load, each of said means being self-contained and removable from said crusher without need first to discharge any of said fluid therefrom, and means for adjusting the spacing between said elements, said adjusting means being effective independently of said fluid in said housing.

2. The device of claim 1 wherein said housing is provided with a floating piston interposed for slidable movement therein between said first named closed end and said main piston, said gaseous fluid being disposed between said first named closed end and said floating piston and a lubricating, substantially noncompressible fluid between said main and floating pistons.

3. The device of claim 1 wherein said main piston is provided with a piston rod extending from said housing through the other of said closed housing ends, said gaseous fluid being disposed between said main piston and said first named closed end of said housing, whereby said means has a maximum over-all length.

4. The device of claim 2 wherein said floating piston is provided with a peripheral, axially extending recess in its outer longitudial surface in order to form with the inner surface of said housing a lubricant-containing chamber, said floating piston having a passage from said chamber to the lubricant containing space between said pistons.

5. In a crusher of the gyratory type having a frame, a crushing bowl mounted rigidly to said frame having a downwardly opening inner crushing surface, and a crushing mantle therebelow having a generally vertical mainshaft journaled in said frame above and below said mantle and an upwardly facing outer crushing surface operatively spaced from said bowl surface and adapted to crush material thereagainst by gyratory movement of the lower journal of said shaft, the spacing between said surfaces being adjustable by vertical movernent of said mantle and shaft relative to said bowl and frame, the combination therewith of self-contained gas hydraulic means both to adjust the spacing between surfaces and to maintain a predetermined spacing therebetween up to a predetermined load therebetween and to accommodate an overload by resiliently increasing said spacing, said means including at least one piston housing having closed opposite ends, a main piston in said housing slidable between said ends, and a gaseous fluid under pressure between said piston and .one of said closed ends of said housing, said means being operatively associated with said frame and shaft so that thrust between said cnushing surfaces is communicated to said housing and piston against the pressure of said fluid, said pressure being such that the total force exerted thereby is suflicient to maintain said predetermined spacing between said bowl and mantle as long as the crushing load therebetween does not exceed said predetermined load, said means being removable from said crusher without need first to discharge any of said fluid therefrom, and means for adjusting the spacing between said bowl and mantle, said adjusting means being effective independently of said fluid in said housing.

6. The device of claim 5 wherein said means is interposed between said frame and the lower end of said shaft to act substantially axially of the latter, and said piston is provided with a piston rod extending from said housing through the other of said housing ends, said fluid being located between said piston and said first named closed end of said housing, whereby said spring means has a maximum overall length, said adjusting means being operative against one end of said spring means to provide vertical adjusting movement of said shaft and mantle relative to said bowl and frame.

7. The device of claim 6 wherein said housing is provided with a floating piston interposed for slidable movement therein between said first named closed housing end and said main piston, said gaseous fluid being disposed between said first named closed housing end and said floating piston and a lubricating, noncompressible fluid between said main and floating pistons.

8. The device of claim 7 wherein said floating piston is provided with a peripheral, axially extending recess in its outer wall in order to form with the inner wall of said housing a lubricant containing chamber, said floating piston having a passage from said chamber to the lubricant containing space between said pistons.

9. In a crusher of the cone type having a frame, a crushing bowl mounted to said frame having a downwardly opening inner crushing surface, and a crushing cone therebelow having an upwardly facing outer crushing surface operatively spaced within and from said cone surface and adapted to crush material thereagainst by eccentric movement of the axis of said cone relative to the axis of said bowl, the spacing between said cone and bowl being adjustable by vertical axial movement of said bowl relative to said frame and cone, the combination therewith of means to maintain a predetermined spacing between said surfaces up to a predetermined load therebetween and to accommodate an overload by resiliently increasing said spacing, said means including a plurality of self-contained gas hydraulic cylinders, each of said cylinders having opposite closed ends, a main piston in said cylinder slidable between said ends having a piston rod connected thereto and extending beyond said cylinder through one of said ends, and a gaseous fluid under pressure between said piston and one of said closed cylinder ends, said means being spaced about the outer surface of said bowl and operatively connected to said bowl and frame so that the crushing load is received against the pressure of said fluid, said pressure being such that the sum of the forces exerted thereby is suflicient to maintain said predetermined spacing between said cone and bowl as long as the load therebetween does not exceed said predetermined load, each of said means being removable from said crusher without need first to discharge any of said fluid therefrom, there being no fluid connection between any of said cylinders, and means for adjusting the spacing between said cone and bowl, said adjusting means being effective independently of said fluid in said cylinders.

110. The device of claim 9 wherein said cylinder is provided with a floating piston interposed for slidable movement therein between said main piston and the closed end of said cylinder remote from that through which said piston rod extends, said gaseous fluid being disposed be tween said last-named closed end and said floating piston and a lubricating, noncompressible fluid between said main and floating pistons, whereby said means has a maximum over-all length.

11. The device of claim 10 wherein said floating piston is provided with a circumferential, axially extending recess in its outer wall in order to form with the inner wall of said cylinder a lubricant containing annulus, said floating piston having a passage from said annulus to the lubricant containing space between said pistons.

References Cited by the Examiner UNITED STATES PATENTS 2,021,895 11/1935 Newhouse 241-211 X 2,667,309 1/1954 Becker 241231 X 2,680,571 6/1954 Bjarme 241215 X 2,856,035 10/1958 Rohacs.

2,873,763 2/1959 Mercier 92-182 X 2,925,959 2/1960 Werner 241290 X 3,019,009 1/1962 Reifurth 267-64 3,099,406 7/1963 Kautz 241-32 ROBERT C. RIORDON, Primary Examiner. D. KELLY, Assistant Examiner.

Claims (1)

1. 5. IN A CRUSHER OF THE GYRATORY TYPE HAVING A FRAME, A CRUSHING BOWL MOUNTED RIGIDLY TO SAID FRAME HAVING A DOWNWARDLY OPENING INNER CRUSHING SURFACE, AND A CRUSHING MANTLE THEREBELOW HAVING A GENERALLY VERTICAL MAINSHAFT JOURNALED IN SAID FRAME ABOVE AND BELOW SAID MANTLE AND AN UPWARDLY FACING OUTER CRUSHING SURFACE OPERATIVELY SPACED FROM SAID BOWL SURFACE AND ADAPTED TO CRUSH MATERIAL THEREAGAINST BY GYRATORY MOVEMENT OF THE LOWER JOURNAL OF SAID SHAFT, THE SPACING BETWEEN SAID SURFACES BEING ADJUSTABLE BY VERTICAL MOVEMENT OF SAID MANTLE AND SHAFT RELATIVE TO SAID BOWL AND FRAME, THE COMBINATION THEREWITH OF SELF-CONTAINED GAS HYDRAULIC MEANS BOTH TO ADJUST THE SPACING BETWEEN SURFACES AND TO MAINTAIN A PREDETERMINED SPACING THEREBETWEEN UP TO A PREDETERMINED LOAD THEREBETWEEN AND TO ACCOMMODATE AN OVERLOAD BY RESILIENTLY INCREASING SAID SPACING, SAID MEANS INCLUDING AT LEAST ONE PISTON HOUSING HAVING CLOSED OPPOSITE ENDS, A MAIN PISTON IN SAID HOUSING SLIDABLE BETWEEN SAID ENDS, AND A GASEOUS FLUID UNDER PRESSURE BETWEEN SAID PISTON AND ONE OF SAID CLOSED ENDS OF SAID HOUSING, SAID MEANS BEING OPERATIVELY ASSOCIATED WITH SAID FRAME AND SHAFT SO THAT THRUST BETWEEN SAID CRUSHING SURFACES IS COMMUNICATED TO SAID HOUSING AND PISTON AGAINST THE PRESSURE OF SAID FLUID, SAID PRESSURE BEING SUCH THAT THE TOTAL FORCE EXERTED THEREBY IS SUFFICIENT TO MAINTAIN SAID PREDETERMINED SPACING BETWEEN SAID BOWL AND MANTLE AS LONG AS THE CRUSHING LOAD THEREBETWEEN DOES NOT EXCEED SAID PREDETERMINED LOAD, SAID MEANS BEING REMOVABLE FROM SAID CRUSHER WITHOUT NEED FIRST TO DISCHARGE ANY OF SAID FLUID THEREFROM, AND MEANS FOR ADJUSTING THE SPACING BETWEEN SAID BOWL AND MANTLE, SAID ADJUSTING MEANS BEING EFFECTIVE INDEPENDENTLY OF SAID FLUID IN SAID HOUSING.

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