Abstract
Disclosed is a deflection distributor refitting kit for a roller crusher. According to the disclosure the deflection distributor refitting kit comprises a deflection distributing shaft, thrust rods each having first and second ends and mounts for attachment of the deflection distributing shaft at a frame of the roller crusher, wherein a first end of each of said thrust rods is attached to the deflection distributing shaft via a lever, wherein a second end of each of the thrust rods is arranged to be attached to a movable bearing housing of the roller crusher, and wherein the deflection distributing shaft comprises first and second shaft parts which are interconnected by means of a shock absorbing unit. Also disclosed is a method for mounting the deflection distributor refitting kit, as well as a roller crusher comprising a deflection distributor.
Claims
1. A deflection distributor refitting kit for a roller crusher, characterized in that it comprises a deflection distributing shaft, thrust rods each having first and second ends and mounts for attachment of said deflection distributing shaft at a first and a second side of a frame of said roller crusher, wherein a first end of each of said thrust rods is attached to said deflection distributing shaft via a lever, wherein a second end of each of said thrust rods is arranged to be attached to a movable bearing housing of said roller crusher, wherein the deflection distributing shaft comprises first and second shaft parts which are interconnected by means of a shock absorbing unit.
2. The deflection distributor refitting kit according to claim 1, wherein the shock absorbing unit is arranged to damp a relative torsional movement between the first and second shaft parts.
3. The deflection distributor refitting kit according to claim 1, wherein the shock absorbing unit has an adjustable damping and/or spring rate.
4. The deflection distributor refitting kit according to claim 1, wherein the shock absorbing unit comprises a pneumatic or hydraulic damper.
5. The deflection distributor refitting kit according to claim 4, wherein the shock absorbing unit comprises a check valve.
6. The deflection distributor refitting kit according to claim 1, wherein the shock absorbing unit comprises a torque coupling comprising one or more elastomeric elements.
7. The deflection distributor refitting kit according to claim 6, wherein the elastomeric elements are pre-compressed.
8. The deflection distributor refitting kit according to claim 6, wherein the elastomeric elements are incompressible and wherein a shock absorbing effect is achieved by deformation of the elastomeric elements.
9. The deflection distributor refitting kit according to claim 1, wherein the deflection distributing shaft is axially split/divided into the first and second shaft parts.
10. The deflection distributor refitting kit according to claim 9, wherein the shock absorbing unit is arranged between the first and second shaft parts.
11. The deflection distributor refitting kit according to claim 1, wherein one of the first and second shaft parts at least partially surrounds the other shaft part.
12. The deflection distributor refitting kit according to claim 1, wherein the shock absorbing unit is arranged within the deflection distributing shaft.
13. The deflection distributor refitting kit according to claim 1, wherein the shock absorbing unit is arranged external to the deflection distributing shaft.
14. The deflection distributor refitting kit according to claim 10, wherein each of the first and second shaft parts comprises a lever and wherein the shock absorbing unit is attached to each of said levers.
15. A deflection distributor refitting kit according to claim 1, further comprising at least one replacement roll for a roll crusher, which roll has a flange attached to each end thereof, and which flange extends in a radial direction of the roll and has a height above an outer surface of the roll.
16. A deflection distributor refitting kit according to claim 1, further comprising replacement bearings for the rollers.
17. A deflection distributor refitting kit according to claim 1, wherein the first and second shaft parts are rigid.
18. A deflection distributor refitting kit according to claim 1, wherein the first and second shaft parts are hollow and have a wall thickness of 10 to 200 mm.
19. A deflection distributor refitting kit according to claim 1, wherein end supports are provided which are arranged to be mounted at the frame of the roller crusher at said first and second sides thereof.
20. A method for mounting a deflection distributor refitting kit according to claim 1 to a roller crusher, said roller crusher comprising a frame; a first and a second crusher roll arranged axially in parallel with each other, said first crusher roll being supported in bearing housings arranged in the frame, said second crusher roll being supported in bearing housings which are configured to be movable; and a hydraulic system configured to adjust the position of the second crusher roll and a crushing pressure between the two crusher rolls; characterized in that the method comprises attaching the second ends of the thrust rods to the movable bearing housings respectively; and attaching the deflection distributing shaft at said frame by means of the mounts, said deflection distributing shaft comprising first and second shaft parts which are interconnected by means of a shock absorbing unit.
21. A method for mounting a deflection distributor refitting kit according to claim 34, wherein said deflection distributor refitting kit is mounted in parallel to the hydraulic system of the roller crusher.
22. A roller crusher, said roller crusher comprising; a frame; first and second crusher rolls arranged axially in parallel with each other, said first crusher roll being supported in bearing housings which are arranged in the frame, said second crusher roll being supported in bearing housings which are configured to be movable; and a hydraulic system configured to adjust the position of the second crusher roll and a crushing pressure between the two crusher rolls, wherein the roller crusher further comprises a deflection distributor, wherein said deflection distributor comprises a deflection distributing shaft, mounts for attaching said deflection distributing shaft at said frame of said roller crusher and thrust rods each having first and second ends, wherein a first end of each of said thrust rods is attached to said deflection distributing shaft via a lever, and wherein a second end of each of said thrust rods is attached to a movable bearing housing of said second crusher roll, wherein the deflection distributing shaft comprises first and second shaft parts which are interconnected by means of a shock absorbing unit.
23. The roller crusher according to claim 22, wherein the shock absorbing unit is arranged to damp a relative torsional movement between the first and second shaft parts.
24. The roller crusher according to claim 22, wherein the shock absorbing unit has an adjustable damping and/or spring rate.
25. The roller crusher according to claim 22, wherein the shock absorbing unit comprises a pneumatic or hydraulic damper.
26. The roller crusher according to claim 25, wherein the shock absorbing unit comprises a check valve.
27. The roller crusher according to claim 22, wherein the shock absorbing unit comprises a torque coupling comprising one or more elastomeric elements.
28. The roller crusher according to claim 27, wherein the elastomeric elements are pre-compressed.
29. The roller crusher according to claim 27, wherein the elastomeric elements are incompressible and wherein a shock absorbing effect is achieved by deformation of the elastomeric elements.
30. The roller crusher according to claim 22, wherein the deflection distributing shaft is axially split/divided into the first and second shaft parts.
31. The roller crusher according to claim 30, wherein the shock absorbing unit is arranged between the first and second shaft parts.
32. The roller crusher according to claim 22, wherein one of the first and second shaft parts at least partially surrounds the other shaft part.
33. The roller crusher according to claim 22, wherein the shock absorbing unit is arranged within the deflection distributing shaft.
34. The roller crusher according to claim 22, wherein the shock absorbing unit is arranged external to the deflection distributing shaft.
35. The roller crusher according to claim 34, wherein each of the first and second shaft parts comprises a lever and wherein the shock absorbing unit is attached to each of said levers.
36. The roller crusher according to claim 22, wherein the first and second shaft parts are rigid.
37. The roller crusher according to claim 22, wherein the first and second shaft parts are hollow and have a wall thickness of 10 to 200 mm.
38. The roller crusher according to claim 22, wherein end supports are provided which are arranged to be mounted at the frame of the roller crusher at said first and second sides thereof.
39. A roller crusher according to claim 22, wherein the deflection distributor is connected to the second roll in a manner parallel with the hydraulic system.
40. A roller crusher according to claim 22, wherein one roll of the first and second crusher rolls has a flange attached to each end thereof, and which flange extends in a radial direction of the roll and has a height above an outer surface of the roll.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0160] The invention will be described in more detail and with reference to the appended drawings in which:
[0161] FIG. 1 shows a perspective view of a roller crusher according to prior art.
[0162] FIG. 2A shows a perspective view of a deflection distributor refitting kit according to one embodiment of the first aspect of the disclosed invention.
[0163] FIG. 2B shows a perspective view of a deflection distributor refitting kit according to one embodiment of the first aspect of the disclosed invention.
[0164] FIG. 2C shows a perspective view of a deflection distributor refitting kit according to a second embodiment of the first aspect of the disclosed invention.
[0165] FIG. 2D shows a perspective view of a deflection distributor refitting kit according to a third embodiment of the first aspect of the disclosed invention
[0166] FIG. 2E shows a perspective view of a deflection distributor refitting kit according to another embodiment.
[0167] FIG. 3 shows a perspective view of a roller crusher with a deflection distributor according to an embodiment of the third aspect of the disclosed invention.
[0168] FIG. 4 shows a schematic bottom view of an arrangement with the deflection distributor and the first and second crusher rolls.
[0169] FIG. 5 shows a schematic view of deflection distribution changes during uneven feed characteristics along the length of the crushing gap within the roller crusher with a deflection distributor according to one embodiment of the first aspect of the disclosed invention.
[0170] FIG. 6 shows a deflection distributor refitting kit according to another embodiment of the first aspect of the disclosed invention.
[0171] FIG. 7 shows a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0172] FIG. 8 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0173] FIG. 9 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0174] FIG. 10 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0175] FIG. 11 shows a part of a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0176] FIG. 12 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0177] FIG. 13 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0178] FIG. 14 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the disclosed invention.
[0179] FIG. 15 shows a roller crusher with a deflection distributor refitting kit according to a further embodiment of the disclosed invention.
[0180] FIG. 16 shows a schematic view of a deflection distributor refitting kit and a control system according to a further embodiment of the disclosed invention.
[0181] FIG. 17 shows a perspective view of a roller crusher with a deflection distributor refitting kit according to a further embodiment of the first aspect of the disclosed invention.
[0182] FIG. 18 shows a side view of a roller crusher with a deflection distributor refitting kit according to an embodiment of the first aspect of the disclosed invention.
DETAILED DESCRIPTION
[0183] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplifying embodiments of the invention are shown. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, and to fully convey the scope of the invention to the skilled addressee. Like reference characters refer to like elements throughout.
[0184] FIG. 1 shows a roller crusher 1 according to the prior art. Such roller crusher 1 comprises a frame 2 in which a first, fixed crusher roll 3 is arranged in bearings 5, 5′. The bearing housings 35, 35′ of these bearings 5, 5′ are fixedly attached to the frame 2 and are thus immoveable. A second crusher roll 4 is arranged in the frame 2 in bearings 6, 6′ which are arranged in the frame 2 in a slidable moveable manner. The bearings 6, 6′ can move in the frame 2 in a direction perpendicular to a longitudinal direction of the first and second crusher rolls 3, 4. Typically a guiding structure 7, 7′ is arranged in the frame on first and second sides 50, 50′ along upper and lower longitudinal frame elements 12, 12′, 13, 13′ of the roller crusher 1. The bearings 6, 6′ are arranged in moveable bearing housings 8, 8′ which can slide along the guiding structure 7, 7′. Further, a number of hydraulic cylinders 9, 9′ are arranged between the moveable bearing housing 8, 8′ and first and second end supports 11, 11′ which are arranged near or at a first end 51 of the roller crusher 1. These end supports 11, 11′ attach the upper and lower longitudinal frame elements 12, 12′, 13, 13′ and also act as support for the forces occurring at the hydraulic cylinders 9, 9′ as they are adjusting the gap width and reacting to forces occurring at the crusher rolls due to material fed to the roller crusher 1. Such roller crushers work according to the earlier disclosed crushing technique called interparticle crushing, and the gap between the crushing rolls 3, 4 is adjusted by the interaction of feed load and the hydraulic system effecting the position of the second crusher roll 4. As stated above, such a prior art roller crusher suffers from delay in adjusting the position of the second crusher roll 4. In case of uneven load along the length of the crushing gap or in case of tramp material entering into the crushing gap, especially when entering into the gap off-center, the second crushing roll 4 may skew and the hydraulic system 10, 10′ is too slow to adjust the position of the movable bearing housings keeping a constant feed pressure, and the movable bearing housings may jam in the guides 7, 7′ and, in case of non-crushable material, the surface of the crushing rolls may be damaged by the non-crushable material, and the whole frame 2 of the roller crusher 1 may become oblique.
[0185] FIGS. 2A and 2B show a deflection distributor refitting kit 100 according to the present invention. Firstly, the components of the deflection distributor refitting kit 100 will be described and thereafter, the advantages of the deflection distributor refitting kit 100 will be described in detail. The deflection distributor refitting kit 100 comprises a deflection distributing shaft 20 and levers 25, 25′ attached at respective ends of the deflection distributing shaft 20. The deflection distributing shaft 20 comprises two interconnectable sub-shafts 201 and 202, and in FIGS. 2A and 2B the two sub-shafts 201, 202 are shown interconnected by means of a shock absorbing unit 204. Further, arranged at each end of the deflection distributing shaft 20 is a mount 24, 24′ which is used to mount the deflection distributing shaft 20, or the sub-shafts 201, 202 of the deflection distributor refitting kit 100 to a frame 2 of a roller crusher 1. The deflection distributing shaft 20 comprises rotational bearings, preferably spherical bearings, in each end thereof allowing the deflection distributing shaft 20 to rotate in relation to the mounts. The levers 25, 25′ each comprise a shank 26, 26′ which are attached with a first end thereof to the deflection distributing shaft 20 and which extends in a radial or tangential direction of the deflection distributing shaft 20. Attached to a second end of each of the levers 26, 26′ is a first end 27, 27′ of a thrust rod 21, 21′. Second ends 28, 28′ of the thrust rods are intended to be attached to the moveable bearing housings 8, 8′ of the roller crusher 1. Each of the levers 25, 25′ is attached to a first end 27, 27′ of a respective thrust rod 21, 21′ such that a longitudinal axis of the lever 25, 25′ is arranged substantially perpendicular to a longitudinal axis of the thrust rod 21, 21′. Further, the longitudinal axis of the lever 25, 25′ passes through the central axis of the deflection distributing shaft 20 and a pivotal point of the lever 25, 25′ and the thrust rod 21, 21′. The shock absorbing unit 204 comprises two shanks 205, 205′ each attached to a respective sub-shaft 201, 202. Attached to one end of each shank 205, 205′ is a shock absorber 206. This shock absorber can comprise for example elastic elements which are preset to deform or decompress at a given load such that the deflection distributor refitting kit 100 can perform its functions during normal load conditions, i.e. maintaining the rolls of the roller crusher parallel with each other but as soon as the forces in the mechanical connection between the moveable bearing housings exceed a predefined threshold, the shock absorbing unit 204 will allow a relative rotational movement between the sub-shafts 201, 202. This will prevent damage to the deflection distributor refitting kit 100 and to the roller crusher to which the deflection distributor refitting kit 100 is mounted. It should be noted that stroke of the shock absorber 206 could be limited to only eliminate the load spikes that may sometimes occur in roller crushers but still maintain the rolls of the roller crusher in a more or less parallel orientation such that any flanges arranged on any the rolls will not come in contact with the outer surface of the other roll, which could potentially damage the flanges. Thus, the shock absorbing unit 204 will certain allow for a limited amount of un-parallelism only. This will still be enough to cut out the load spikes that may cause structural damage to the deflection distributor refitting kit 100 or the roller crusher. The elastic elements of the shock absorber 206 may be pre-compressed to avoid fatigue over time and to avoid or at least reduce hysteresis. The shock absorber may also comprise a hydraulic component using a damping medium and valves, possibly adjustable, that will have desired shock absorbing function. FIG. 2B exemplifies the function of the present invention. A compression force F1 acts on the first thrust rod 21 and a tension force F2 acts on the second thrust rod 21′. If these forces exceed a predefined threshold, where forces above this threshold are deemed to be possibly damaging to the equipment, a small relative rotational movement R1-R2, is allowed between the sub-shafts 201, 202. As soon as the above-threshold event has passed, the shock absorbing unit will return to an initial state where the rolls of the roller crusher are again parallel with each other.
[0186] FIG. 2C shows an embodiment in which subshaft 201 is inserted into subshaft 202 and wherein shock absorbing unit 204 is located inside subshaft 202. This has a major advantage in that the deflection distributing shaft as a whole will not take up any additional space in comparison with a rigid, single shaft. Furthermore, the shock absorbing unit 204 is protected from dirt etc.
[0187] FIG. 2D shows an embodiment where the shock absorbing unit 204 comprises a torsional joint comprising a first hub 207 attached and rotationally fixed to first subshaft 201 by means of e.g. a splined connection 210, a second hub 208 which is attached and rotationally fixed to the second subshaft 202, and a plurality of elastic elements 209. The second hub 208 comprises pockets 211, each of which can accommodate two elastic elements 209 and one flange element 212 of the first hub 207. When the two sub-shafts 201, 202 are connected, in this embodiment by inserting the first hub and the elastic elements 209 into second hub 208, the sub-shafts 201, 202 will function as a rigid deflection distributing shaft as long as a predetermined force is not achieved. This means that the mechanical connection will distribute the movements of the bearing housings such that the rolls will be maintained in a parallel state. When, however, this threshold is exceeded, the flanges 212 of the first hub 207 will cause a deformation or decompression of the elastic elements 210 between which the flange is sandwiched. Similar to previous embodiments, the elastic elements 210 may be pre-compressed to avoid fatigue over time and to avoid or at least reduce hysteresis. The elastic elements may be incompressible such that the shock absorbing effect is caused by deformation instead of compression. As soon as the above-threshold event has passed, the shock absorbing unit will return to an initial state where the rolls of the roller crusher are again parallel with each other. The embodiment of FIG. 2D has an advantage in that the outer dimensions of the shock absorbing unit are the same, or substantially the same as the deflection distributing shaft as such, allowing for mounting also in situations with restricted room for additional equipment.
[0188] FIG. 2E shows an alternative deflection distributor refitting kit 100 further comprising a preload arrangement which induces a bias to parts of the deflection distributor refitting kit. In this embodiment, the thrust rods 21, 21′ are provided with means for adjusting the length thereof. In the embodiment disclosed in FIG. 2E, this length adjustment is provided in the form of a threaded solution similar to how a turnbuckle, or stretching screw, functions. The first end 27, 27′ and the second end 28, 28′ are both threaded and connected by means of a threaded center part 22, 22′. The two ends of the center part 22, 22′ comprises one left hand thread and one right hand thread such that when the center part 22, 22′ is rotated, both the first end 27, 27′ and the second end 28, 28′ will be retracted or both will be extracted. This means that the overall length of the thrust rods 21, 21′ can be adjusted. This, in turn, means that by shortening one of the thrust rods 21, 21′ and lengthening the other, a bias can be introduced into the mechanical connection between the bearing housings 8, 8′ such that joints of the mechanical connection are biased in one direction. For example, a pin 30, 30′ inserted into a bearing will be biased towards an inner surface of the bearing. When vibrations occur, the pin 30, 30′ is already abutting a surface of the bearing and shock loads can be eliminated or at least reduced. It is acknowledged that this bias, which is done in a direction parallel with the longitudinal direction of the thrust rods 21, 21′, will be more effective in reducing the detrimental effects of loads from vibrations in one direction only and less so with respect to vibrations in other directions. For example, a thrust rod 21, 21′ which has been extended such that it is put under compressional load, will be less prone to damage from vibrational forces acting to further compress the thrust rod 21, 21′. This since any clearance between the parts of the joints, e.g. a pin 30, 30′ and inner surface of a bearing of a pivot bracket 31, 31′, will already be removed such that the parts abut each other when the force from the vibration acts upon the joint, thus avoiding a shock load. Thereby the effect of at least 50% of the vibration events can be reduced, assuming that the forces are evenly distributed between events causing compression of the thrust rods 21, 21′ and tensioning of the thrust rods 21, 21′. The length adjustment may in the embodiment shown in FIG. 2E be accomplished by rotating of the center part 22, 22′ using a tool that can be applied to opening 23, 23′. This is an example only and the skilled person realizes that this rotation can be performed in many other ways. Locking elements 36, 36′ are also indicated for maintaining a preferred length of the thrust rods 21, 21′. These locking elements 36, 36′ should be applied to both first ends 27, 27′ and second ends 28, 28′. Similar to e.g. the embodiment shown in FIG. 2A, the shaft 20 is split in two subshafts 201, 202 and is provided with a shock absorbing unit 204. The shock absorbing unit 204 comprises two shanks 205, 205′ each attached to a respective sub-shaft 201, 202. Attached to one end of each shank 205, 205′ is a shock absorber 206.
[0189] The deflection distributor refitting kit 100 according to the present invention is arrangeable at previously known roller crushers 1 as shown in FIG. 1. By using the deflection distributor refitting kit 100, problems in previously known roller crushers 1, more specifically skewing problems occurring in roller crusher 1 can be avoided. The gap width between the crusher rolls 3, 4 will vary during use depending on the characteristics and amount of material fed to the roller crusher, and the gap width may also vary along the length of the crusher rolls 3, 4 depending on how the material is fed to the roller crusher 1 and on the characteristics thereof. For example, if more material is located towards a first side 50 of the roller crusher 1, there is a risk that the gap will become wider towards the first end 50 than towards a second side 50′ of the roller crusher 1. The moveable second crusher roll 4 will become askew. This has several disadvantages. For example, the skewing creates forces which the roller crusher 1 is not suitable to handle. The frame 2 is mainly intended to handle forces directed in the longitudinal direction of the roller crusher 1. Further, forces in oblique directions may cause jamming in the guiding structure 7, 7′ and the moveable bearing housings 8, 8′ will get stuck, thus becoming unable to react and move as required by the material feed situation. In order to avoid skewing, it is required that both ends of the second crusher roll 4, 4′ travel the same distance in the same amount of time in response to an event involving uneven feed, i.e. feed situations where the load at one end of the second crusher roll 4 is greater than the load at a second end of the second crusher roll 4. The hydraulic system 10, 10′ comprising hydraulic cylinders 9, 9′ is not able to respond adequately fast to these skewing situations. This type of situations would require that large amounts of hydraulic liquid is displaced within fractions of a second. And not only need a hydraulic system to displace this amount of hydraulic liquid in such short time, it must first also measure the correct amount of liquid to displace. The deflection distributor of the present invention on the other hand, has no problems with this. It is able to immediately transfer an unbalanced load event from one moveable bearing housing 8, 8′ located on one side of the roller crusher 1 to the moveable bearing housing 8, 8′ on the other side of the roller crusher 1. In response to a displacement of one of the moveable bearing housings 8, 8′, the corresponding thrust rod 21, 21′ attached to that moveable bearing housing 8, 8′ will force the corresponding lever 25, 25′ to move, which in turn will cause the deflection distributing shaft 20 to rotate in the rotating bearings in the mounts 24, 24′, thereby causing a corresponding movement of the other lever 25, 25′, the other thrust rod 21, 21′ and finally the other moveable bearing housing 8, 8′. This can also be seen in the schematic top view of FIG. 5. Here, a situation is described where an uneven feed event between the crusher rolls 3, 4 off-center, more towards the first side 50 of the roller crusher. This will cause the first thrust rod 21 to move towards the first end 51 of the roller crusher 1 and it in turn will cause first lever 25 also to move towards the first end 51 and by its coupling to the deflection distributing shaft 20, the deflection distributing shaft 20 will be forced to rotate in the rotational bearings in the mounts 24, 24′. This rotation will cause a movement of the second lever 25′ to move similar to the first lever 25 and the movement of the second lever 25′ will force the second thrust rod 21′ to perform a movement which is identical to that of the first thrust rod 21 thereby facilitating the parallel movement of the two moveable bearing housings 8, 8′ such that the second, moveable crusher roll 4 is kept parallel with the first, fixed, crusher roll 3 at all times.
[0190] As can be seen in FIG. 5, the resulting forces acting on the bearings of the bearing housings 8, 8′ are directed in the same direction, but the force acting on the first bearing housing 8 will be greater. It is this difference in resulting loads that would otherwise cause skewing of the second crusher roll 4 and jam the moveable bearing housings 8, 8′ in the guiding structure and also cause excessive wear of the roller crusher 1 as a whole. The deflection distributor 100 according to the disclosed invention will act on the excessive load in one end and automatically deflect the same distance in the second end and thereby maintain parallelism, and will also provide for a parallel return, as well as provide for a constant feed pressure profile within the roller crusher 1. In FIG. 3, a roller crusher 1 with a deflection distributor refitting kit 100 according to one embodiment of the present invention can be seen, and in FIG. 8 and FIG. 9, a roller crusher 1 with a deflection distributor refitting kit 100 according to another embodiment of the present invention can be seen. In FIG. 3 it is seen that the mounts 24, 24′ for the deflection distributing shaft 20 are attached to the end supports 11, 11′ of the frame 2 and the thrust rods 21, 21′ pass through channels 29, 29′ in the end supports 11, 11′. It can readily be understood that other solutions than channels are conceivable, for example recesses or similar in the outer or inner side walls of the end supports 11, 11′.
[0191] In the embodiments shown in FIG. 3 and FIG. 18, the hydraulic system 10 comprises four hydraulic cylinders 9, 9′, two on each side 50, 50′ of the roller crusher 1, and each of the thrust rods 21, 21′ extends in between the two hydraulic cylinders 9, 9′ respectively. This is advantageous in that it can help achieve a balanced load situation. The mounts 24, 24′ are bolted to the respective end supports 11, 11′ but other fastening options are conceivable to the person skilled in the art, e.g. welding. The thrust rods 21, 21′ are in these embodiments attached to the moveable bearing housings 8, 8′ by means of first pivot bracket 31, 31′ and to the levers 25, 25′ by means of second pivot brackets 30, 30′. Advantages of these pivot brackets will be discussed in detail in relation with FIG. 6. Other fastening means are also conceivable, for example the trust rods 21, 21′ may be fixedly attached by bolting onto the movable bearing housings 8, 8′, and may be attached to the levers 25, 25′ with semi-spherical slide bearings.
[0192] The embodiment shown in FIG. 17, may also comprise four hydraulic cylinders, two on each side of the roller crusher 1, and each of the thrust rods 21, extends in between the two hydraulic cylinders 9, respectively. The hydraulic cylinders 9 are shown in position for the embodiment in FIG. 18.
[0193] FIG. 4 shows a schematic bottom view of a deflection distributor according one embodiment of the disclosed invention arranged and coupled with the movable bearings housings 8, 8′ of the second crusher roll 4 and the first crusher roll 3 is arranged in parallel therewith. With the deflection distributor according to the disclosed invention a mechanical connection between the bearing housings 8, 8′ arranged at the respective two ends of the second crusher roll 4 is created. Thus, any uneven material feed (tramp or feeding characteristics) which is unevenly distributed within the length of the crushing gap) acting on the second crusher roll 4 will, with the overload distributor according to the disclosed invention, result in a parallel movement of both bearing housings 8, 8′, independently of the position of this material uneven feed of material along the length of the crushing gap.
[0194] FIG. 6 shows a deflection distributor refitting kit 100 according to another embodiment of the disclosed invention. The deflection distributor refitting kit 100 comprises the deflection distributor shaft 20 with shanks 25, 25′, and trust rods 21, 21′, and further comprises end supports 11, 11′ onto which the deflection distributor shaft 20 is mounted with the mounts 24, 24′. The trust rods 21, 21′ are arranged in channels 29, 29′ which are provided in each end support 11, 11′ to allow a substantially linear movement of the thrust rods 21, 21′ through the channels 29, 29′. The thrust rods 21, 21′ are arranged with pivot brackets 30, 30′ in first ends 27, 27′ thereof to the shanks 25, 25′, and are also arranged with pivot brackets 31, 31′ in a second end 28, 28′ thereof for future attachment to the movable bearing housings 8, 8′ in a roller crusher 1. The pivot joint 30, 30′ of the thrust rod 21, 21′ and the shank 25, 25′ ensures that a linear or mainly linear movement in the thrust rod 21, 21′ is transferred to the lever 25, 25′ and thus to the deflection distributing shaft 20 without causing unnecessary torsional load in the thrust rod 21, 21′ or in the lever 25, 25′. The pivot joint 31, 31′ of the thrust rod 21, 21′ and the movable bearing housing 8, 8′ will ensure that the linear movement of the bearing housing 8, 8′ is transferred to the thrust rod without causing unnecessary torsional load in the thrust rod 21, 21′ or bearing housing 8, 8′.
[0195] The end supports 11, 11′ are arranged to be easily mounted to the frame 2 of the roller crusher 1 at a first side 50 and a second side 50′ thereof, and may also be arranged to be coupled to at least one hydraulic cylinder 9, 9′ of the hydraulic system 10, 10′ of the roller crusher 1. In the embodiment shown in FIG. 6, the channels 29, 29′ for the thrust rods 21, 21′ on each side 50, 50′ are arranged between two coupling points 32, 32′ for the hydraulic cylinders 9, 9′, and in a position to be aligned perpendicular to and in the same horizontal plane as the central axis of the second crusher roll 4 in the roller crusher 1. With this arrangement, the deflection distributor 100 will act in parallel with the hydraulic system 10, 10′, as described earlier, and allows for an optimal load distribution when fitted to a roller crusher 1 and the load may be distributed in the same vertical plane and thereby cause less stress and torsional forces in the frame 2 of the roller crusher 1.
[0196] FIG. 7 shows a deflection distributor refitting kit 100 according to another embodiment of the disclosed invention. This deflection distributor refitting kit 100 comprises, in addition to the parts shown in FIG. 6, also accumulators 33, 33′ which are arranged to be connected with the hydraulic system 10, 10′ on the roller crusher. By providing the accumulators together with the deflection distributor refitting kit 100 the positioning of the accumulators 33, 33′ may be optimized not to interfere with mount position for the deflection distributor shaft and the thrust rods, but also to keep the accumulators as close as possible to the hydraulic cylinders 9, 9′ in order to minimize pipelines for the transportation of hydraulic fluid back and forth from the accumulators 33, 33′ and the hydraulic cylinders 9, 9′. The accumulators 33, 33′ may further be adapted for the parallel action of the deflection distributor of the disclosed invention.
[0197] The deflection distributor refitting kit 100 in FIG. 7 further comprises one or more replacement rolls 3, 4 for a roller crusher 1. One of the rolls 3 has a flange 34, 34′ attached to each end thereof. The flanges 34, 34′ extend in a radial direction of the roll, and has a height above an outer surface of the roll. As the parallel movement of the second crusher roll 4 is ensured with the deflection distributor refitting kit according to the disclosed invention, the first roll 3 may be equipped with such flanges without any risk of misalignment and thereby no risk of damaging flanges or the surface of the crusher rolls. By having flanges 34, 34′ arranged onto one of the crusher rolls 3 provides a much higher crushing result and a higher overall crushing pressure, and provide an increases throughput of about 10-20% or sometimes even more, in the roller crusher.
[0198] In an alternative embodiment the flanges are arranged on the second crusher roll 4, instead on the first crusher roll 3.
[0199] The deflection distributor kit 100 of FIG. 7 further comprises replacement bearings 5, 5′, 6, 6′ for the crusher rolls 3, 4. Bearings 5, 5′, 6, 6′ used in a roller crusher 1 are worn out after a period of time, and needs to be replaced and to replace these at the same time as the crusher rolls 3, 4 are replaced is beneficial and effective for the refurbishment and service work. Further these replacement bearings may be optimized for a roller crusher with a deflection distributor system arranged thereon, as disclosed above in the summary part of the description.
[0200] FIG. 8 discloses an alternative embodiment of the deflector distribution kit 100 where a crossbar 60 is attached to and interconnects the pivot brackets 31, 31′. The crossbar 60 allows for the thrust rods 21, 21′ to be mounted with an offset to the end supports 11, 11′ and/or the moveable bearing housings 8, 8′. This makes it possible to apply the invention without having to provide channels 29, 29′ in the end supports 11, 11′. In some situations, such channels 29, 29′ are unfavorable due to the presence of e.g. hydraulic hoses or pipes or electrical installations on or within the end supports 11, 11′. By using a crossbar 60 it is possible to have the thrust rods 21, 21′ to be arranged alongside the end supports 11, 11′ which can be left intact. The crossbar 60 can be attached to the pivot brackets 31, 31′ by means of pin 61, here indicated as vertical pins. In this embodiment, the crossbar has a circular cross-section. Of course, other cross-sections are conceivable as well. The thrust rods 21, 21′ are pivotably attached to the crossbar 60 by means of e.g. spherical bearings or bushings or any other suitable means that may withstand the forces and maintain the pivotable connection. The deflection distributing shaft 20 is here indicated to fit within the frame of a roller crusher 1 but it is of course possible to arrange the deflection distributing shaft 20 behind, similar to how it is shown in FIG. 3, or on top of the frame 2 instead. As can be seen in FIG. 8, the deflection distributing shaft 20 is rotatably arranged between inner surfaces of end supports 11, 11′. This provides a very compact construction which leaves a small footprint on the site where it is used. As a matter of fact, this solution ensures that the footprint of the roller crusher provided with the deflector distribution kit according to the invention has an identical footprint as that of the roller crusher without the deflector distribution kit. This is an important aspect since space is always limited on sites using this type of equipment.
[0201] FIGS. 9 and 10 disclose alternative embodiments of the deflector distribution kit 100 where offset brackets 131, 131′ are arranged at the moveable bearing housings 8, 8′. Similar to the crossbar 60 in FIG. 8, these offset brackets 131, 131′ allows for the thrust rods 21, 21′ to be mounted with an offset to the end supports 11, 11′ and/or the moveable bearing housings 8, 8′. This makes it possible for the thrust rods 21, 21′ to pass alongside of the end supports 11, 11′. Preferably, the thrust rods 21, 21′ pass the end supports 11, 11′ on the inner side. This reduces the footprint of the roller crusher in comparison with a solution where they pass on an outer side. As can be seen in FIG. 9, the deflection distributing shaft 20 is arranged on the rear side of the frame 2 whereas the deflection distributing shaft 20 in FIG. 10 is arranged within the frame 2. Both alternatives have their specific advantages. For example, the solution in FIG. 10 leaves a smaller footprint whereas the solution in FIG. 9 requires less free height.
[0202] FIG. 11 discloses an alternative embodiment of the deflector distribution kit 100 where a crossbar 60 is provided. Similar to the embodiment in FIG. 8, the crossbar 60 in this embodiment extends between two adjacent, moveable bearing housings 8, 8′. The crossbar 60 in this embodiment comprises two adjacent, substantially flat crossbar elements 62 arranged on an upper and a lower side respectively of the pivot brackets 31, 31′ and pivotably connected to the pivot brackets 31, 31′ by means of vertical pin 61. The pin 61 can, however, be arranged in other directions than vertical, such as horizontal, as well or instead. Thrust rods 21, 21′ are pivotably connected to the crossbar 60 by means of vertical pin 81 and the thrust rods 21, 21′ are at their respective first ends pivotably connected to the levers by means of pivot bracket 30, 30′, similar to previous embodiments. The solution of this embodiment has, similar to the embodiments of FIGS. 8 and 9, the advantage that the thrust rods 21, 21′ can pass alongside the end supports 11, 11′. This embodiment also allows for the crossbar 60 to be assembled from smaller, separate parts, for example upper and lower substantially flat crossbar elements 62. This makes it easier to install and remove the crossbar. The flat crossbar elements 62 provide excellent structural rigidity for this purpose without excessive use of material.
[0203] FIG. 12 discloses an embodiment similar to that shown in FIG. 11. Here, the thrust rods 21, 21′ are more compact and preferably made from an integral part provided with bushings or bearings 64 through which pin 81 is inserted. This solution provides improved rigidity and due to the simple structure, it has long life span.
[0204] FIG. 13 discloses an embodiment having a crossbar 60. Crossbar 60 comprises at its ends brackets 65, 65′ which are attachable to the moveable bearing housings 8, 8′ via pivot brackets 31, 31′ by means of vertical pin 61. Similar to the embodiment in FIG. 11, the thrust rods 21, 21′ are compact and made from an integral part provided with bushings or bearings 64 for long life span. Between the brackets 65, 65′, the crossbar 60 comprises a tubular section 66 fixedly connected to the brackets 65, 65′. The tubular section 66 may also be made up from two pieces, creating a split crossbar. This has advantages in that it simplifies assembly and disassembly. Instead of using a tubular section 66, other cross-sections are of course conceivable, for example rectangular, oval or any other suitable shape.
[0205] FIGS. 14 and 15 disclose an embodiment where a lever arm 70 is provided. A first portion of lever arm 70, here indicated as an end portion, is pivotally connected to a lower part of the frame 2 of the roller crusher. A second portion, here indicated as a second end portion of lever arm 70, is pivotally connected to the lever 25, 25′ through links 71, 71′ and the thrust rods are connected to the lever arm 70 at a position lying in between these first and second portions. The thrust rods 21, 21′ are attached to the moveable bearing housings via offset brackets 131, 131′ which allow the thrust rods 21, 21′ to pass alongside both the inner and the outer side of the frame 2 of the roller crusher, hence not requiring any, or at least very few, modifications of the roller crusher as such. The arrangement of a pivotal point at a lower part of the frame 2 has advantages in that the forces occurring can be handled in excellent manner by the frame 2 since the forces can be divided by the upper and the lower parts of the frame 2 in a convenient manner. Further, as can be seen in FIGS. 14 and 15, the deflection distributing shaft 20 can be arranged on top of the frame 2 of the roller crusher without creating any additional foot print. Even in a situation where the second roll 4 is in a fully retracted position, i.e. where the gap between the rolls 3, 4 is at a maximum, no part of the deflection distributor refitting kit adds to the length of the roller crusher to which it is mounted. In the FIGS. 14 and 15, a total of four lever arms 70 are disclosed and a total of four thrust rods 21, 21′ are disclosed. It is obvious to the skilled person that the number and specific arrangements of these elements can be chosen as deemed suitable. For example, one lever arm 70 for each side of the roller crusher would also be conceivable and even a single, centrally arranged lever arm 70 would be possible. The same applies for the thrust rods, 21, 21′ and the links 71, 71′, namely that the number of elements and position thereof can be varied. This embodiment also maintains a substantially horizontal position of the thrust rods 21, 21′ throughout the entire stroke thereof which is advantageous since it reduces the forces introduced in the frame 2. Similar to other embodiments described herein, spherical bearings are suitable for the pivotal connections between the frame 2, lever arm 70, thrust rods 21, 21′, moveable bearing houses, links 71, 71′, levers 25, 25′.
[0206] FIG. 16 discloses an embodiment having a control system 200 in combination with the deflection distributor. The control system 200 is configured to monitor a skew between the first and second crusher rolls 3, 4 and wherein the control system 200 is further configured to reduce pressure in the hydraulic system 10, 10′ on the first or second side in response to a determination that the skew exceeds a predefined threshold value. The provision of such control system reduces the forces acting on the deflection distributor such that the structural dimensions of the parts can be reduced and focus on achieving maximum rigidity can be reduced without sacrificing anti-skewing properties. Here, no complicated hydraulic control systems are required. Instead, in response to a determined exceeding of a predefined threshold skew value, it is sufficient to just reduce the pressure in the hydraulic system on the least deflected side. Such pressure reduction can be achieved by simply opening a valve with sufficient area such that hydraulic liquid can be drained from the system into a suitable container. When the skewing is reduced below the threshold value, the valve is closed and hydraulic liquid may be returned into the hydraulic system 10, 10′. In FIG. 16 it can be seen that a non-even load has occurred and that the crushing force acting on the moveable crusher roll 4 is greater towards a first side 50 of the roller crusher. The deflection distributor will compensate for this and minimize skew but if the occurring forces are too big, at some point the deflection distributor may reach its limits. In such a case, the control system 200 will notice that the skew exceeds a predefined threshold. In response to this, the control system will reduce pressure at the second side 50′, being less deflected, thus helping the deflection distributor in its attempts of minimizing skew. The pressure reduction can be made in many ways, one being as simple as opening a valve in order to evacuate hydraulic fluid from the hydraulic system 10′ letting it flow into a vessel 300′. As soon as the skewing is back below the predefined threshold, the valve may be closed and the hydraulic fluid may be returned into the hydraulic system 10′. It should be noted that the control system in accordance with this embodiment can be integrated in an already existing control system of the roller crusher. It can also be constituted by a completely separate system or even be performed manually.
[0207] As stated above, FIGS. 17 and 18 show a perspective view and a side view of a roller crusher of one embodiment of the present invention. The two hydraulic cylinders 9 are shown with the thrust rod 21 arranged in-between in FIG. 18, while the hydraulic cylinders have been left out in FIG. 17, in order to show the other details more clearly. In this embodiment the mounts 24 are bolted to the respective end supports 11, but as stated earlier other fastening options are conceivable to the person skilled in the art, e.g. welding. The thrust rods 21 are in this embodiment attached to the moveable bearing housings 8, by means of first pivot bracket 31 and to the levers 25, by means of second pivot brackets 30. Other attachment methods, as described in other parts of the application, are conceivable. In this embodiment the deflection distributing shaft 20 with levers 25 and mounts 24 are mounted to a lower end of the frame 2 of the roller crusher 1, while the deflection distributing shaft 20 with levers 25 and mounts 24 are mounted to an upper end of the frame 2 in the embodiment shown in FIG. 3. Arranging the deflection distributing shaft 20 with levers 25 and mounts 24 at or near a lower end of the frame 2 as shown in FIGS. 16 and 17 is sometimes advantageous. It makes maintenance of the bearings of the deflection distributing shaft 20 and levers 25 easier since they are accessible from the lower end of the frame, i.e. at or near ground level. Also, installation is less cumbersome since the parts do not have to be lifted far from the ground. Often, there is a top platform at or near an upper end of the frame 2 with which access is given to equipment from above. With the embodiment shown in FIGS. 17 and 18, such platform does not need to be modified to make room for e.g. the deflection distributing shaft 20 and mounts 24. In FIGS. 17 and 18, the thrust rods 21 are shown to pass through openings in end supports 11. However, other means are conceivable as disclosed elsewhere in this application, for example as disclosed in FIGS. 8-13 where the thrust rods pass alongside the end supports 11.
[0208] The skilled person realizes that a number of modifications of the embodiments described herein are possible without departing from the scope of the invention, which is defined in the appended claims.
[0209] When mounted in a roller crusher 1, the deflection distributor 100 according to the disclosed invention is idling (no force or pressure action) during balanced feed and uniform material feed distribution, and is only in operation during unstable feed situations, such as non-uniform material feed characteristics along the length of the crushing gap and/or non-crushable material entering off center within the crushing gap. Thus, the deflection distributor 100 is controlling each bearing housing deflection separately by manipulating the accumulator spring constant for the roller crusher keeping a constant feed pressure profile.
[0210] The deflection distributor 100 according to the disclosed invention provides the required instant parallel deflection response time to handle the non-uniform material feed characteristics along the length of the crushing gap.
[0211] Existing solutions within prior art for dealing with non-uniform feed characteristics and/or tramp comprise moving oil from one side to the other to compensate for skewing events developed by uneven feed by means of valves and pumps. However, these systems are not quick enough to limit the skewing to an acceptable level which allows for use of flanges on one of the crusher rolls and at the time preserving the shock absorbing spring effect without overloading or underloading the system. Further, when compensating for non-uniform feed characteristics, the hydraulic systems in these prior art solutions normally adjusts the second crusher roll 4 away from the center of the crushing gap, which decreases the crushing pressure and provides inadequate crushing within the roller crusher. This increases the amount of material which needs to be recirculated.
[0212] Keeping the crusher rolls in parallel and a more or less constant crusher pressure on the feed over the length of the crusher rolls as well as over time is key and important for a uniform production. Further, the inventive deflection distributor position and suspension in a roller crusher together with the design thereof minimizes the inertia and resulting forces from it during rapid movement of the second crusher roll 4.
[0213] Further, as is disclosed in the summary part the deflection distributor may also be arranged with a roller crusher having two crushing rolls being movable within the frame, and in such cases one deflection distributor may be arranged for each crusher roll. It is further possible to arrange the deflection distributor on a roller crusher having crushing rolls which have bearing housings which are pivotably movable relative to a frame. Further, it is possible to arrange mounts of the distributor refitting shaft on a separate stand in the proximity to an end side of a roller crusher frame holding a movable crusher roll instead of connecting it directly to the frame, and still attach the thrust rods to the movable bearing housings of the movable crusher roll.
[0214] The skilled person also realizes that the lever as described herein, should in general be interpreted as the function provided thereby. For example, it is possible to attach the first end of the thrust rod in an off-center manner to the deflection distributing shaft, thereby creating the required leverage. In general, the lever can be achieved in many ways by creating a distance between the attachment of the first end of the thrust rod and a rotational axis of the deflection distributing shaft.
[0215] The skilled person also realizes that the reduction of pressure in the hydraulic system as described in one embodiment herein, may refer to a partial pressure reduction only or to a total pressure release, as the requirements may be.
[0216] The skilled person realizes that the different embodiments described herein are compatible with each other and the advantages discussed herein with respect to the different embodiments are equally applicable when the embodiments are combined with each other. For example, the embodiments described with respect to the shock absorbing unit described in FIGS. 2A-2E are all possible to combine with the individual embodiments described in FIGS. 3-18.
