Roller crusher

Abstract

The present disclosure relates to a roller crusher having two substantially parallel rollers arranged to rotate towards each other in opposite directions and separated by a gap, each roller having two ends, the roller crusher comprising: a flange attached to at least one end of one of the rollers, the flange extending in a radial direction of the roller, the flange extending in a radial direction of the roller, the roll crusher comprises a flanged roll having a height higher than the outer surface of the roll, where the roll crusher further comprises at least one scraper arranged at the end of the flanged roll for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roll. According to the utility model, at least one scraper comprises a scraping element with a scraping surface, and the scraping surface comprises polycrystalline diamond.

Description

Technical Field

[0001] The present disclosure relates to a roller crusher having two substantially parallel rollers, wherein the roller crusher comprises a flange attached to at least one end of one of the rollers. Background Art

[0002] When crushing or grinding rocks, ores, cement clinker and other hard materials, a roller crusher with two roughly parallel rollers can be used, which rotate in opposite directions towards each other and are separated by a gap. The material to be crushed is then fed into the gap. One type of roller crusher is called a high-pressure grinding roller or high-pressure roller crusher. This type of crushing has been described in US4357287, in which it was determined that when trying to achieve fine and / or very fine crushing of materials, it is actually not necessary to strive to achieve the crushing of individual particles. On the contrary, it was found that by generating high compression forces, causing the particles to agglomerate or clump during the crushing process, significant energy savings and increased production can be achieved. This crushing technology is called inter-particle crushing. Here, the material to be crushed or pulverized is crushed not only by the crushing surface of the roller, but also by the particles in the material to be crushed, and is therefore called inter-particle crushing. US4357287 illustrates that this agglomeration can be achieved by using much higher compression forces than before. For example, previously used high compression forces of up to 200kg / cm 2 The solution in US4357287 suggests using at least 500kg / cm 2 and up to 1500kg / cm 2 In a roller crusher with a roller diameter of 1 meter, 1500kg / cm 2 This translates into forces of more than 200,000 kg per meter of roller length, whereas previously known solutions could and should achieve only a fraction of these forces. Another peculiarity of inter-particle crushing is that the roller crusher should be fed with material to be crushed in a chock-and-screw manner, meaning that the gap between the two opposing rollers of the roller crusher should always be filled with material along its entire length and should also always be filled to a certain height above the gap in order to keep it full at all times and maintain particle-to-particle compression. This will increase throughput and reduce to finer materials. This is in stark contradiction to older solutions, where single particle crushing was always emphasized as the only way to obtain fine and very fine particle size reductions.

[0003] The characteristic of inter-particle crushing, unlike some other types of crushing equipment (such as classifiers), is that it does not produce a series of shocks and widely varying pressures during use. Instead, equipment using inter-particle crushing exerts very high, more or less constant pressure on the material in the crushing zone formed in and around the gap between the rollers.

[0004] In order to maintain the crushing effect over the entire length of the grinding rollers, flanges may be provided at the ends of the crushing rollers; one flange at each end of one roller, or one flange at one end of each roller (but on opposite ends of the roller crusher). By such an arrangement, a more efficient and uniform roller feed inlet may be produced. The flanges will allow the preferred material pressure to be produced for the material being fed over the entire length of the crusher rollers. It has been shown that the capacity of a given roller crusher can be increased by 20%, sometimes even more, by using flanges. A general problem associated with grinding rollers without flanges is that the ratio between the roller diameter and the roller width is very important due to a significant edge effect, i.e. the crushing result at the edge of the roller is reduced. This is because material may escape over the edge of the roller, thereby reducing the crushing pressure on the material at the edge of the roller towards the gap. Therefore, in the absence of flanges, due to the reduced breakage at the edge caused by the lower pressure, it is necessary to recover the material escaping from the roller and some of the material that has passed through the gap at the edge of the crushing roller.

[0005] However, during operation of a flanged grinding mill, the flanges and the edges of the opposing crushing rolls are subject to significant stress and wear, and buildup material can accumulate at the transition between the crushing roll surface and the flanges. This excess buildup material needs to be removed consistently during operation of the grinding mill.

[0006] The prior art proposes a scraper element for removing accumulated material at the transition between the crushing roller surface and the flange, for example, see AU2018264756 or US5054701.

[0007] Starting from this point, it is an object of the present disclosure to provide a roller crusher with a flange, wherein the flange and the edges of the opposite roller crusher ends are subject to less stress and wear. Utility Model Content

[0008] According to a first aspect of the present disclosure, this and other objects are fully or at least partially achieved by a roller crusher having two substantially parallel rollers arranged to rotate towards each other in opposite directions and separated by a gap, each roller having two ends, the roller crusher comprising:

[0009] a flange attached to at least one end of one of the rollers,

[0010] The flange extends in the radial direction of the roller,

[0011] The flange has a height (H) exceeding the outer surface of the roller,

[0012] wherein the roller crusher further comprises at least one scraper arranged at the end of the roller having the flange for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller, and

[0013] Each of the at least one scraper blades includes a scraping element having a scraping surface including polycrystalline diamond (PCD).

[0014] A first advantage of at least one scraper blade comprising a scraping element having a scraping surface comprising polycrystalline diamond (PCD) is a significantly extended wear life of the scraper blade. Typically, such a scraping surface would comprise a wear resistant material such as ceramic or a composite material comprising tungsten carbide, titanium carbide or vanadium carbide, but for a scraping surface comprising polycrystalline diamond (PCD), the wear life can be extended by up to about 50 times compared to a composite material comprising, for example, tungsten carbide alone.

[0015] It is conceivable to provide other surfaces of the scraper element with polycrystalline diamond (PCD). For example, the side surface of the scraper element may include polycrystalline diamond (PCD). Expressed in another way, the scraping surface may extend to also include the side surface of the scraper element. Therefore, it should be understood that the current utility model concept should not be interpreted as being limited to scrapers having a forward-facing surface including polycrystalline diamond (PCD).

[0016] According to one embodiment, at least one scraper is arranged at a distance from the flange and / or from the outer surface at the end of the roller.

[0017] The distance between the scraper and the roller surface and / or the flange can be defined selectively using a minimum roller distance and a minimum flange distance, respectively. The minimum roller distance is defined as the minimum distance between the scraper and the outer surface of the roller. Similarly, the minimum flange distance is defined as the minimum distance between the scraper and the inner surface of the flange.

[0018] According to one embodiment, the scraping element further comprises a wear resistant material, wherein polycrystalline diamond (PCD) is at least partially embedded therein. In an alternative embodiment, the polycrystalline diamond (PCD) may be attached to the surface of the wear resistant material of the scraping element.

[0019] The wear resistant material may comprise a ceramic material such as titanium carbide, vanadium carbide or tungsten carbide; a metal ceramic composite material, for example a cemented carbide such as titanium carbide, tungsten carbide or vanadium carbide with cobalt as a binder; or a metal matrix composite material comprising titanium carbide, tungsten carbide or vanadium carbide.

[0020] In one embodiment, the wear-resistant material is a cemented carbide including tungsten carbide and cobalt as a binder, wherein the binder content may be 10-15 wt %.

[0021] In one embodiment, polycrystalline diamond (PCD) is embedded in tungsten carbide, vanadium carbide, or titanium carbide.

[0022] According to one embodiment, the scraping element may include a layer of polycrystalline diamond (PCD).The polycrystalline diamond (PCD) layer may have a thickness of 0.4 to 3.2 mm, or 1.0 to 2.0 mm, or 1.35 to 1.8 mm, or 1.4 to 1.6 mm, or about 1.5 mm.

[0023] The diamond grain size of the polycrystalline diamond (PCD) of the scratched surface may be 0.8 to 30 μm, as determined by image analysis using a scanning electron microscope (SEM).

[0024] The grain size of the diamond can be measured by various measurement techniques, such as a laser size analyzer or a scanning electron microscope (SEM). An example of a laser size analyzer is the Malvern particle size analyzer device based on laser diffraction. The value determined using the laser size analyzer may be the initial diamond grain size, which in some embodiments may be subsequently subjected to high pressure and high temperature sintering. When the diamond particles have been sintered and compacted to form the scratched surface polycrystalline diamond (PCD), image analysis by scanning electron microscopy is used to determine the final microstructure grain size distribution, i.e. the diamond grain size of the scratched surface polycrystalline diamond (PCD).

[0025] According to one embodiment, the scraping surface of at least one scraper is arranged to be inclined relative to the normal to the inner surface of the flange, and the inclination is such that the distance between the normal to the inner surface of the flange and the scraping surface decreases towards the flange. The normal is defined as a straight line orthogonal to the plane defined by the inner surface of the flange.

[0026] One advantage of having the scraping surface inclined relative to the normal to the inner surface of the flange and decreasing distance toward the flange is that material removed from the corner formed by the outer surface of the roller and the inner surface of the flange will be pushed toward the center of the roller by the inclined scraping surface rather than being squeezed and compacted between the scraper element and the inner surface of the flange.

[0027] According to one embodiment, the scraping surface is substantially planar. Therefore, according to this embodiment, the varying distance as described above can be further expressed as an angle defined between the scraping surface and the normal N. The angle can be 1 to 15°, or 2 to 10°, or 3 to 8°, or 4 to 6°, or 5°.

[0028] According to one embodiment, at least one scraper has a surface facing the flange having an extension from the scraping element toward the rear end of the at least one scraper, wherein the structure and arrangement of the at least one scraper is such that the distance between the surface facing the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension. An advantage of a scraper having such an arrangement is that material removed from a location in the corner formed by the outer surface of the roller and the inner surface of the flange will tend to flow along the surface facing the flange of the scraper, and as the distance away from and downstream of the scraping surface increases, the removed material will be allowed to be removed toward the center of the roller rather than being squeezed and compacted between the scraper and the inner surface of the flange.

[0029] According to one embodiment, the surface facing the flange may be substantially planar. Thus, according to this embodiment, the varying distance as described above may be further expressed as an angle defined between the surface facing the flange and the inner surface of the flange. The angle may be 5 to 25°, or 5 to 20°, or 5 to 15°, or 8 to 12°, or 10°.

[0030] According to one embodiment, at least one scraper has a surface facing away from the flange, which has an extension from the scraping element towards the rear end of the at least one scraper, wherein the at least one scraper is constructed and arranged so that the distance between the surface facing away from the flange and the inner surface of the flange decreases towards the scraping element over at least a portion of the extension. On at least one scraper, the surface facing away from the flange is opposite to the surface facing the flange. Likewise, it is beneficial that the scraper provides a surface that will push the removed material towards the center of the roller.

[0031] According to one embodiment, the surface facing away from the flange comprises a substantially planar surface. Therefore, for this embodiment, the variable distance as described above can be further expressed by an angle defined between the surface facing away from the flange and the inner surface of the flange. The angle can be 5 to 25°, or 5 to 20°, or 5 to 15°, or 8 to 12°, or 10°.

[0032] According to one embodiment, the scraping element comprises a front part and a rear part attached to each other, and wherein the front part has a scraping surface. The front part and the rear part of the scraping element may comprise wear-resistant materials of different components. For example, the front part may comprise polycrystalline diamond (PCD) and tungsten carbide or vanadium carbide on the scraping surface, while the rear part may comprise tungsten carbide or vanadium carbide. The front part and the rear part may be attached to each other by brazing, but may also be manufactured in one piece with polycrystalline diamond provided at the scraping surface of the scraping element.

[0033] According to one embodiment, the rear portion has a surface facing the flange and a surface facing away from the flange, said surfaces being substantially parallel to the inner surface of the flange.

[0034] According to one embodiment, at least one scraper is arranged in the lower part of the roll crusher.

[0035] The expression "lower part of the roller crusher" should be interpreted broadly herein. The term is intended herein to cover all positions in which the at least one scraper will be located below a plane defined by the two rotation axes of the crushing roller. Thus, the above-described embodiment may alternatively be expressed in which the at least one scraper is arranged such that the scraping surface of the at least one scraper is located below a substantially horizontal plane associated with the two rotation axes of the crushing roller.

[0036] This can be advantageous as it allows material to leave the crushing rollers by being output with the crushed material at the lower end of the roller crusher.

[0037] According to one embodiment, at least one scraper is disposed at approximately 6 to 9 o'clock, 7-9 o'clock, or 7-8 o'clock of the roller when viewing the roller from the side showing clockwise rotation.

[0038] According to one embodiment, the at least one scraper is arranged such that the scraping surface of the at least one scraper is at least partially facing downwards to allow the removed material to leave the roller and the scraping surface by gravity.

[0039] This may be advantageous as it may prevent scraped material from accumulating on the scraped surface which could risk material being deposited on said surface.

[0040] According to one embodiment, at least one scraper has a fastening position, which is located at a certain distance from the outer surface of the roller, wherein the at least one scraper is arranged so that the scraping surface of the at least one scraper is located at or continuous with a radial axis, which extends from the rotation axis of the roller and passes through the fastening position.

[0041] The phrase "continuous to" means that during the rotation of the roller, a point of the outer surface of the roller first passes through a radial axis extending from the rotation axis of the roller through the fastening position and then passes continuously through the scraping surface of at least one scraper. Thus, the scraping surface is positioned continuously with the radial axis extending from the rotation axis of the roller through the fastening position, as seen in the rotation direction of the roller.

[0042] This may be advantageous if material accumulated on the flange and / or on the outer surface at the end of the roller becomes too hard to remove and the at least one scraper strikes the non-removable material sufficiently that the attachment of the scraper to the roller crusher may break. When such detachment occurs, the at least one scraper will move away from the outer surface of the roller in this arrangement, rather than striking the outer surface of the roller at the end of the roller.

[0043] For this detachment, at least one scraper can be rigidly fastened. However, this rigid fastening can be configured to withstand impact forces up to a predetermined threshold force to ensure that the outer surface of the flange or roller end is not at risk of being damaged by a collision between the scraper and the non-removable material.

[0044] According to one embodiment, the roller crusher further comprises at least one holding clamp for the at least one scraper, the at least one holding clamp being connected to the frame of the roller crusher at the fastening location of the at least one scraper.

[0045] According to one embodiment, at least one retaining fixture comprises at least one bracket and at least one wedge element, the structure and arrangement of which is used to attach at least one scraper to at least one bracket so that the angular position of at least one scraper is offset relative to the angular position of at least one bracket in the rotation plane of the roller.

[0046] According to one embodiment, the roller crusher further comprises flexible holding means arranged to interconnect the at least one scraper and a frame of the roller crusher.

[0047] According to one embodiment, the at least one scraper is at least two scrapers arranged successively to each other at the end of the roller with the flange for at least partially removing material accumulated on the flange and / or on the outer surface of the roller end.

[0048] The roller crusher of this embodiment of the first aspect may be advantageous because it allows selective removal of material accumulated on the grinding roller during operation. Specifically, the roller crusher of the first aspect allows at least partial removal of material accumulated on the outer surface of the flange and / or the roller end. This particular part of the roller crusher is particularly prone to accumulation of material, which may risk damaging the roller if it is not removed. The roller crusher of this embodiment of the first aspect provides at least two scrapers arranged continuously with each other along the end of the roller. The at least two continuously arranged scrapers have many advantages.

[0049] A first advantage of at least two scrapers arranged in series is the extended operating time. The scraper that first encounters the accumulated material (herein referred to as the "front scraper" or "first-in-line scraper") will be subject to severe wear. Therefore, over time, the material of the front scraper will gradually wear away due to wear, thereby increasing the distance between the front scraper and the roller surface and / or flange. As this wear process gradually occurs, the scraper that is continuously arranged behind the front scraper (herein referred to as the "second scraper" or "first following scraper") will be increasingly subject to accumulated material, thereby gradually taking on more and more of the tasks that the current scraper performed when it was new. Therefore, this way of gradually transferring the scraping responsibility from the front scraper to the first following scraper allows to extend the operating time before the scraper must be replaced, thereby reducing the downtime of the roller crusher and helping to improve the overall efficiency of the plant. As will be readily understood by a person skilled in the art, providing a second following scraper after the first following scraper will have exactly the same effect as the first following scraper starting to wear. Therefore, for some embodiments of the roller crusher, the number of consecutive scrapers can be more than two.

[0050] A second advantage of at least two scrapers arranged in series is the reduction of the impact of scraper failure on the operation of the roll crusher. The harsh environment to which the scrapers are exposed during operation may from time to time lead to irreparable damage to the scrapers. Usually, the most adversely affected is the front scraper, since it is located at the front and therefore bears the full impact of the newly deposited material. The scrapers may be damaged not only structurally. In addition, or their attachment to the roller mill may be destroyed, resulting in the scraper usually falling off, leading to an immediate termination of the scraping performance of this particular scraper. By providing more than one scraper operating in the same area, a redundancy is achieved that allows at least one scraper to break without having to shut down the roll crusher.

[0051] According to one embodiment, at least two scrapers are arranged in the lower part of the roll crusher.

[0052] According to one embodiment, at least two scrapers are arranged at approximately 6 to 9 o'clock, 7-9 o'clock or 7-8 o'clock of the roller when viewing the roller from the side showing clockwise rotation.

[0053] According to one embodiment, the at least two scrapers are arranged such that the scraping surfaces of the at least two scrapers are at least partially facing downwards to allow the removed material to leave the rollers and the scraping surfaces by gravity.

[0054] Again, this may be advantageous as it may prevent scraped material from accumulating on the scraped surface, which could risk material being deposited on said surface.

[0055] According to one embodiment, at least two scrapers each have a respective fastening position or have a common fastening position, which is located at a certain distance from the outer surface of the roller, wherein the at least two scrapers are arranged so that the position of each scraping surface of the at least two scrapers is located at or continuous with a radial axis, which extends from the rotation axis of the roller and passes through the respective fastening position or the common fastening position.

[0056] Likewise, the phrase "continuously to" means that during the rotation of the roller, a point of the outer surface of the roller first passes through a radial axis extending from the rotation axis of the roller through the corresponding fastening position or the common fastening position and then passes continuously through the scraping surface of at least one scraper. Thus, the scraping surface is positioned continuously with the radial axis extending from the rotation axis of the roller through the corresponding fastening position or the common fastening position, as seen in the rotation direction of the roller.

[0057] Likewise, for embodiments having only at least one scraper, it may be advantageous if material accumulated on the outer surface of the flange and / or roller end becomes too hard to remove and the at least two scrapers strike the non-removable material sufficiently that the attachment of the scraper to the roller crusher may break. When such a breakaway occurs, the at least two scrapers will move away from the outer surface of the roller in this arrangement, rather than striking the outer surface of the roller at the end of the roller.

[0058] For this disengagement, at least two scrapers may be rigidly fastened. However, this rigid fastening may be configured to withstand impact forces up to a predetermined threshold force to ensure that the outer surface of the flange or roller end is not at risk of being damaged by collision between the scraper and the non-removable material.

[0059] In another embodiment, at least one or at least two scrapers are pivotally fixed and biased toward the working position of at least one or at least two scrapers. The size of the bias should keep at least one or at least two scrapers in the working position until a predetermined threshold force is reached. Similarly, such a predetermined threshold force is set to ensure that the outer surface of the flange and / or the roller end will not be damaged by the collision between the scraper and the non-removable material. It is also possible to consider the use of an unbiased pivot fastener combined with a torque limiter. For such an embodiment, at least one or at least two scrapers will appear to be rigidly attached to the roller crusher until at least one or at least two scrapers have been subjected to a force exceeding a certain threshold force, at which the torque limiter is actuated and at least one or at least two scrapers are allowed to swing away from the roller surface.

[0060] The phrase "working position" refers to the position of the scraper relative to the outer surface of the roll crusher and the flanges, in which position it is used to at least partially remove material accumulated on the flanges and / or the outer surface of the roll ends.

[0061] According to one embodiment, at least two consecutive scrapers are equidistant from the flange and / or the outer surface of the roller end.

[0062] This may be advantageous because the scraper(s) following the leading scraper will serve as backup scrapers. Thus, even if these following scrapers are not actively contributing to scraping, they will be ready to take on the task if the leading scraper fails.

[0063] According to one embodiment, at least two consecutive scrapers are arranged at different distances from the flange and the outer surface at the end of the roller.

[0064] According to one embodiment, at least two consecutive scraper blades are arranged at decreasing distances from the flange and / or the roller surface, seen from the front scraper blade to the consecutive scraper blade(s).

[0065] As mentioned above, the phrase "front scraper" refers to the scraper that will first encounter the accumulated material when the roller rotates during the operation of the roller crusher (also referred to as the "first-in-line scraper" in this article), and the term "following scraper" refers to the scraper (one or more) that will encounter the accumulated material after the front scraper.

[0066] This can be advantageous as each scraper has a dedicated scraping duty to scrape the material to be removed. This will reduce impact and wear on each scraper and allow for longer operation before the scraper must be replaced, thus reducing roll crusher downtime and helping to improve the overall efficiency of the plant.

[0067] The distance between the scraper and the roller surface and / or the flange can be defined using a minimum roller distance and a minimum flange distance, respectively. The minimum roller distance is defined as the minimum distance between the scraper and the outer surface of the roller. Similarly, the minimum flange distance is defined as the minimum distance between the scraper and the inner surface of the flange. Therefore, two scrapers arranged at different distances from the roller surface and / or the flange can be expressed alternatively as the two scrapers having different minimum roller distances from the roller surface and / or different minimum flange distances from the flange.

[0068] According to one embodiment, the at least two continuous scraper blades comprise at least two subsets of at least two continuous scraper blades, wherein the at least two continuous scraper blades in each subset are arranged at the same distance from the flange and / or the outer surface at the roller end.

[0069] This may be an advantage, since the at least two subsets of at least two consecutively arranged scraper blades will extend the operating time.

[0070] According to one embodiment, the subsets of consecutive scrapers are arranged at decreasing distances from the flange and / or the outer surface at the end of the roller, seen from a front subset to the consecutive subset(s).

[0071] Likewise, this may be advantageous because the at least two subsets of at least two scrapers arranged in series will extend the operating time. The front scraper in each subset of the at least two scrapers will first encounter the accumulated material (will be subject to wear). Over time, the material of the front scraper in each subset of the at least two scrapers will therefore gradually wear away due to wear, thereby increasing the distance between the front scraper in each subset of the at least two scrapers and the outer surface and / or flange of the roller. As this wear process gradually occurs, the second scraper of each subset of the at least two scrapers, which is arranged in series with and behind the front scraper in each subset of the at least two scrapers, will be increasingly subject to accumulated material, thereby gradually taking on more and more of the tasks that the front scraper in each subset of the at least two scrapers performed when the subset of the at least two scrapers was new. This gradual transfer of scraping responsibility from the front scraper in each subset of the at least two scrapers to the first following scraper in each subset of the at least two scrapers thus allows to extend the operating time before the subset of the at least two scrapers has to be replaced, thereby reducing the downtime of the roll crusher and helping to improve the overall efficiency of the plant. As will be readily appreciated by a person skilled in the art, providing a second following subset of at least two scrapers after a first following subset of at least two scrapers or at least three scrapers in each subset of scrapers will have exactly the same effect as the second scraper starting to wear in each subset. Thus, for some embodiments of the roll crusher, the number of consecutive scrapers in each subset and the number of consecutive subsets of at least two scrapers may be greater than two.

[0072] According to one embodiment, at least two subsets of continuous scrapers are identical to each other and are arranged at equal distances from the flange and the outer surface at the end of the roller.

[0073] According to one embodiment, each scraping surface of at least two consecutive scrapers is arranged to be inclined relative to the normal to the inner surface of the flange, and the inclination is such that the distance between the normal to the inner surface of the flange and said scraping surface decreases towards the flange. The normal is defined as a straight line orthogonal to the plane defined by the inner surface of the flange.

[0074] This may be advantageous as it allows material to be more easily transported away from the corner between the flange and the outer surface of the roller after being scraped off, thereby facilitating an efficient material removal process.

[0075] According to one embodiment, the at least one scraper is arranged such that the minimum roller distance between the scraper and the outer surface of the roller is at least 31.5 mm.

[0076] According to one embodiment, each of the at least two scrapers is arranged such that the minimum roller distance between each scraper and the outer surface of the roller is at least 31.5 mm. In other words, the at least two scrapers may be arranged at a distance of at least 31.5 mm.

[0077] According to one embodiment, the roller crusher further comprises at least one holding clamp for at least one or both scrapers, which is connected to the frame of the roller crusher at a fastening position of at least one scraper, or at a respective fastening position or a common fastening position of at least two scrapers.

[0078] According to one embodiment, at least one retaining clamp comprises at least one bracket and at least one wedge element, the structure and arrangement of which is used to attach at least one scraper or a related one of at least two scrapers to at least one bracket, so that the angular position of at least one scraper or a related one of at least two scrapers is offset relative to the angular position of at least one bracket in the rotation plane of the roller.

[0079] According to one embodiment, the roller crusher further comprises flexible holding means arranged to interconnect the at least one scraper or at least one scraper of the at least two scrapers and a frame of the roller crusher.

[0080] This may be advantageous if at least one scraper blade may not only be damaged structurally, but its attachment to the roll crusher may break, resulting in the scraper blade generally falling, where it will fall into the chute for the ground material and may hit lower arranged equipment, such as screening equipment or conveying equipment, and will also contaminate the ground material for further processing. By having a flexible retaining device, a scraper blade that breaks its attachment will only result in an immediate termination of the scraping performance of this particular scraper blade, but will not damage the lower arranged equipment or contaminate the ground material.

[0081] According to one embodiment, the roller crusher comprises two flanges, which are attached to opposite ends of one of the rollers, and wherein the at least one scraper comprises a first subset of at least one scraper and a second subset of at least one scraper, the first subset and the second subset are respectively arranged on corresponding end areas of the roller having the two flanges.

[0082] According to one embodiment, the roller crusher comprises two flanges, which are attached to opposite ends of one of the rollers, and wherein the at least two scrapers comprise a first subset of at least two scrapers and a second subset of at least two scrapers, the first subset and the second subset are each arranged on a respective end region of the roller having the two flanges.

[0083] According to one embodiment, at least one mechanical scraper comprises a trigger scraper positioned at a maximum permissible distance from the roller surface and / or the inner surface of the flange, the trigger scraper being configured to send a trigger signal to a control system of the roller crusher upon collision with accumulated material remaining on the outer surface of the flange and / or the roller end.

[0084] According to one embodiment, such a trigger signal may involve initiating a planned service shutdown to replace at least one scraper blade.

[0085] According to one embodiment, such a trigger scraper is located at the maximum allowable distance from the outer surface at the flange and / or the end of the roller, and includes a built-in sensor, such as an accelerometer or a strain gauge. Alternatively, the trigger scraper can be mounted on a retaining fixture with a built-in sensor. Alternatively, the retaining fixture can be attached to the frame of the roller crusher at a fastening position, and the sensor can be arranged in or at the fastening position and configured to output a trigger signal in response to a mechanical impact on the trigger scraper. Therefore, the term "trigger scraper" should not be interpreted as referring to a special type of scraper itself. The trigger scraper can be the same as any other scraper disclosed herein. Instead, the term is used to identify a specific scraper in at least one scraper that is configured to be used as a sensing device to provide information related to material accumulation. This can be achieved in different ways, as long as the mechanical interaction between the accumulated material and the trigger scraper is converted into an output signal.

[0086] The "maximum permissible distance" is a predefined distance beyond which the accumulated material is not allowed to pass. In other words, if the material accumulates to the maximum permissible distance, the accumulation must be cleared, or the machine must be shut down.

[0087] According to one embodiment, the roller crusher further comprises a remote material removal device configured to output a material removal beam to a target area, wherein the remote material removal device and at least one scraper are arranged to be continuous with each other at the end of the roller having a flange for at least partially removing material accumulated on the flange and / or the outer surface at the end of the roller.

[0088] The term "remote material removal device" should be interpreted in this context as a device that can output a beam with material removal capabilities to a target area remote from the device. This means that, in contrast to at least one mechanical scraper, the remote material removal device does not come into contact with the material to be removed. Instead, the material is removed by a material removal beam. The material removal beam has a defined beam direction. This means that the target area can be selected by adjusting the direction of the material removal beam. Depending on the type of remote material removal device, the material is removed by different processes, such as mechanical impact, heating, ablation, exothermic reaction, etc.

[0089] The term "target area" should be interpreted in this article as a limited area or field, which can be defined on the physical object at which the material removal beam of the remote material removal device is directed. Since the material removal beam has a defined direction, the area is limited, which means that the material removal beam has a defined spatial beam cross-section or beam profile. The spatial beam cross-section can be defined by the physical properties of the beam as a function of the radial distance from the beam direction axis. The physical properties can have an uneven distribution. This means that the material removal efficiency can vary within the target area. However, the material in all parts of the target area will be removed. The target area can be defined on the roller surface and / or the inner surface of the flange. Alternatively, the target area can be defined on the accumulated material accumulated on the flange and / or on the outer surface of the roller. There is an important difference between the two optional schemes: in the former case, once any accumulated material is removed, the material removal beam will impact the roller surface and / or the inner surface of the flange. This may be advantageous because it allows complete cleaning of the surface to be provided effectively and reliably. However, by removing roller surface material and / or flange surface material with a material removal beam, there may be a risk of inadvertently damaging the surface. For this case, the latter option may be beneficial. Here, the target area is selected so that the material removal beam does not hit the roller surface and / or the inner surface of the flange, so these surfaces are protected from the material removal beam at all times. The latter alternative can be provided by guiding the material removal beam substantially tangentially to the roller surface at the end of the roller with the flange.

[0090] The wording "the remote material removal device is arranged […] at the roller end" should be interpreted in this document as the remote material removal device being arranged at a position where the remote material removal device can provide sufficient material removal in the intended target area, that is, the area defined on the accumulated material present at the outer surface of the roller end and / or at the flange is the intended target area. As will be readily appreciated by those skilled in the art, the efficiency of material removal will depend on the distance between the remote material removal device and the target area and the angle formed by the material removal beam with the target area. The distance to the target area is typically in the range of 50–500 mm. It will also be readily appreciated by those skilled in the art that the rear portion of the remote material removal device may have an elongated body and may therefore be located at a certain distance from the flange and the outer surface of the roller end.

[0091] The roller crusher of this embodiment may be advantageous because it allows selective removal of material accumulated on the grinding roller during operation. In particular, the roller crusher of this embodiment allows at least partial removal of material accumulated on the flange and / or on the outer surface of the roller end. This particular part of the roller crusher is particularly susceptible to accumulation of material, which may risk damaging the roller if not removed.

[0092] A first advantage of at least one or at least two mechanical scrapers and remote material removal devices arranged in series with one another is that a more reliable system is provided for maintaining the accumulated material at the flange within acceptable levels. The at least one or at least two mechanical scrapers will provide a continuous scraping operation. Thus, the at least one or at least two mechanical scrapers will be ready to remove material at any given time during operation. However, since the mechanical scrapers remove material by mechanical interaction with the accumulated material, the at least one or at least two mechanical scrapers will be subject to wear. Since the roll crusher is started with a clean roll, there is no accumulated material at the flange, so during the first period of crushing operation, material will accumulate at the corner transition between the roll surface and the flange, thereby forming a material accumulation. During the first period of time after startup, such as the first hour of operation, the material accumulation will be relatively soft throughout the depth of the material, so the (one or more) mechanical scrapers will be able to effectively remove any excess accumulation at an acceptable wear rate of the at least one or at least two mechanical scrapers and an acceptable level of mechanical stress on the (one or more) clamps that hold the at least one or at least two mechanical scrapers in place relative to the roll crusher. However, after a crusher has been running continuously for a long time, the material buildup will become increasingly compacted, thereby hardening throughout the depth of the material. This will increase the wear rate of at least one or at least two mechanical scrapers and the level of mechanical stress on the (one or more) clamps that hold the at least one or at least two mechanical scrapers in place relative to the roller crusher. This problem is solved by removing the built-up material before it becomes too hard by a remote material removal device. By applying a material removal beam to a target area located at the end of a roller having a flange, the beam can partially or completely remove the material buildup located there. By removing the buildup, the wear life of the (one or more) mechanical scrapers and their (one or more) holding clamps will be increased, thereby providing a more reliable system for keeping the buildup at the flange within acceptable levels.

[0093] Another advantage of at least one or at least two mechanical scrapers and remote material removal devices arranged in succession to each other is that a more flexible and controllable system is provided for removing material accumulated on the grinding roller during operation. Although the (one or more) mechanical scrapers are always in operation, the remote material removal device can be controlled. Such control can, for example, activate the remote material removal for continuous time periods. The time period can be selected according to the conditions on site, i.e. the material to be crushed, humidity, temperature, etc. Alternatively, a feedback control system can be used. However, the obvious disadvantages of remote material removal devices, such as reliable power supply, pressurized water or air supply, dust generated, etc., can be minimized by selectively operating the remote material removal device only when it is most needed. The remaining material is then left for the (one or more) mechanical scrapers to remove.

[0094] Another advantage of at least one or at least two mechanical scrapers and remote material removal devices arranged in succession to each other is that it is easier to control the amount of material removed. During normal crushing operation, it is not necessary to completely clear the accumulated material. It is sufficient to remove the upper layer of material to ensure that the accumulation does not come into contact with the adjacent rollers. However, in certain situations, for example when the roller crusher is shut down for maintenance and replacement of (one or more) mechanical scrapers, it may be beneficial to completely clear the accumulation because it reduces the risk that the accumulated material may obstruct the newly attached (one or more) mechanical scrapers.

[0095] As will be readily appreciated by those skilled in the art from the above description, the combination of at least one or at least two mechanical scrapers and remote material removal devices will work synergistically due to their different advantages and disadvantages.

[0096] According to one embodiment, the target area of ​​the remote material removal device is located in front of the at least two scrapers.

[0097] Preferably, the target area is located in the lower part of the roll crusher. This means that the components of the remote material removal device can be arranged in the upper part of the roll crusher, but the material removal beam can be directed to the target area located in the lower part of the roll crusher.

[0098] According to one embodiment, the target zone of the remote material removal device is disposed at approximately 6 to 9 o'clock, 7-9 o'clock, or 7-8 o'clock of the roll when viewing the roll from the side showing clockwise rotation.

[0099] The term "target area" refers to that portion of the roller surface area and / or that portion of the inner surface of the flange and / or that portion of the outer surface of the material accumulation that may accumulate on the flange and / or on the outer surface of the roller end that will be impacted by the beam at any time during operation of the remote material removal device. Thus, the target area is typically located in front of the remote material removal device.

[0100] The phrase "in front of" means that during the rotation of the roller, if the remote material removal device is active, the target area of ​​the remote material removal device will first be impacted by the remote material removal device and then pass by or be scraped by the at least one or at least two mechanical scrapers on the outer surface and / or flange of the roller. Therefore, before the at least two mechanical scrapers can affect or scrape any material on the specific area or point of the outer surface and / or flange of the roller, the target area of ​​the remote material removal device will act on the accumulated material on the specific area or point of the outer surface and / or flange of the roller.

[0101] According to one embodiment, the remote material removal device is a fluid jet knife.

[0102] The term "fluid jet knife" is to be interpreted herein as a device having a pressurized fluid plenum chamber containing one or more holes or continuous slots through which the pressurized fluid is discharged in the form of a fluid plume during operation of the fluid jet knife. The fluid may be a liquid fluid, such as water. This means that the fluid jet knife may be a water jet knife. Alternatively, the fluid may be a gaseous fluid, such as air.

[0103] As described above, when the mechanical scraper is always in operation, the operation of the remote material removal device can be controlled, and the remote material removal can be started in a continuous period of time, and the target area of ​​the remote material removal device can be arranged in front of at least one or at least two mechanical scrapers. This will be advantageous because the wear of at least one or at least two mechanical scrapers can be reduced, thereby extending the operating time.

[0104] According to a second aspect of the present disclosure, this and other objects are also fully or at least partially achieved by a method of operating a roller crusher for grinding particulate material, wherein the roller crusher has two substantially parallel rollers arranged to rotate towards each other in opposite directions and separated by a gap, each roller having two ends, the roller crusher comprising:

[0105] a flange attached to at least one end of one of the rollers,

[0106] The flange extends in the radial direction of the roller,

[0107] The flange has a height (H) exceeding the outer surface of the roller, wherein the roller crusher further comprises at least one or at least two scrapers arranged successively to each other at the end of the roller having the flange, wherein the method comprises at least the following steps:

[0108] The material accumulated on the outer surface of the flange and / or the roller end is at least partially removed by at least one or at least two scrapers.

[0109] According to an embodiment of the second aspect of the present disclosure, the roller crusher also includes a remote material removal device, which is configured to output a material removal beam toward a target area, wherein the remote material removal device is arranged to be continuous with at least one or at least two continuous scrapers at the end of a roller having a flange, wherein the method also includes at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller with the help of the remote material removal device.

[0110] According to an embodiment of the second aspect of the present disclosure, the roller crusher also includes a remote material removal device, which is configured to output a material removal beam to a target area, wherein the remote material removal device is arranged to be continuous with at least one or at least two continuous scrapers at the end of a roller having a flange, wherein the method also includes intermittently at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller by means of the remote material removal device.

[0111] According to one embodiment of the second aspect, at least two scrapers include a trigger scraper, which is positioned at a maximum allowable distance from the outer surface at the end of the flange and / or the roller, and the trigger scraper is configured to initiate material removal by the remote material removal device when colliding with accumulated material remaining on the outer surface at the end of the flange and / or the roller.

[0112] Again, the "maximum allowable distance" is a predefined distance beyond which the accumulated material is not allowed to pass. In other words, if the material accumulates to the maximum allowable distance, the accumulation must be cleared, or the machine shut down.

[0113] A "trigger scraper" refers to a scraper that is capable of providing a trigger signal to initiate remote material removal when contacting the accumulated material, i.e., step b). The trigger scraper may be a conventional scraper with trigger capability. This can be achieved in different ways. For example, the trigger scraper may have a built-in sensor, such as an accelerometer or a strain gauge. Alternatively, the trigger scraper may be mounted on a retaining fixture with a built-in sensor. Alternatively, the retaining fixture may be attached to the frame of the roll crusher at a fastening position, and the sensor may be arranged in or at the fastening position and configured to output a trigger signal in response to a mechanical impact on the trigger scraper. Therefore, the term "trigger scraper" should not be interpreted as referring to a special type of scraper per se. The trigger scraper may be the same as any other scraper disclosed herein. Instead, the term is used to identify a specific scraper in at least one scraper that is configured to be used as a sensing device to provide information related to material accumulation. This can be achieved in different ways, as long as the mechanical interaction between the accumulated material and the trigger scraper is converted into an output signal.

[0114] According to an embodiment of the second aspect of the present disclosure, such a trigger scraper is positioned at a maximum distance from the outer surface at the end of the flange and / or the roller for sending a signal to the control system of the roller crusher, which signal may involve initiating a planned service shutdown to replace at least two consecutive scrapers.

[0115] According to a third aspect of the present disclosure, there is provided a roller crusher having two substantially parallel rollers arranged to rotate towards each other in opposite directions and separated by a gap, each roller having two ends, the roller crusher comprising:

[0116] a flange attached to at least one end of one of the rollers,

[0117] The flange extends in the radial direction of the roller,

[0118] The height of the flange is higher than the outer surface of the roller, and

[0119] A moving blocking device constructed and arranged to limit the gap between the rollers to a minimum gap of at least 45 mm,

[0120] Wherein the roller crusher further comprises at least one scraper positioned at the end of the roller having the flange, and wherein the scraper is positioned such that a minimum roller distance between the at least one scraper and the outer surface of the roller is at least 70% of the minimum gap.

[0121] The roller crusher of the third aspect may be advantageous because it allows selective removal of accumulated material only to the extent necessary to avoid any harmful effects that the accumulated material may have on the flange and the edge of the opposing crushing roller. It is beneficial to selectively remove only the material that is absolutely necessary to be removed for several reasons. First, the overall wear of the at least one scraper will be reduced because the scraper suffers a significantly smaller degree of wear when the at least one scraper is positioned further away from the roller surface. In addition, it is well known that the risk of accidental failure of the scraper, such as severe and immediate structural damage to the scraper and / or even tearing of the scraper from the roller crusher, will increase with decreasing distance from the roller surface. This is because the mechanical stress on the at least one scraper will increase significantly when it is close to the roller surface. Therefore, the utility model concept is also associated with the extended durability of the at least one scraper and the reduced risk of accidental failure events during operation. Avoiding these unexpected failure events is advantageous because it reduces overall downtime and, importantly, reduces the risk of unexpected blockages in the plant's material chain, which would normally require the unexpected and sometimes challenging shutdown of several adjacent processing machines in the plant to avoid the accumulation of excess feed at the stopped roll crusher.

[0122] As will be readily appreciated by those skilled in the art, in order to prevent any detrimental effects of the accumulated material on the roll crusher, the maximum possible distance between the scraper and the roll surface will be equal to the minimum gap. Within this limit, the scraper will be able to remove sufficient material to allow the two rolls to move relative to each other without the risk of the accumulated material adversely affecting the flange and the edge of the opposing crushing roll, for example, through impact or compression forces. However, since the scraper is constantly subject to wear during operation, positioning the scraper at this distance may not be preferred, as scraper wear will effectively remove material from the scraper, thereby increasing the distance as the crusher operates for an increasing period of time. Through extensive testing, it has been recognized that by placing the scraper at a minimum distance of at least 70% of the minimum gap from the roll having the flange (i.e. the roll where material accumulation occurs), the roll crusher can be operated for an economically acceptable period of time, and the scraper has worn to the extent that the distance between the scraper and the outer surface of the roll will approach the minimum gap, and the scraper must be adjusted in place or replaced.

[0123] The term "movement blocking device" should be interpreted as any device on a roller crusher that is capable of physically preventing the rollers from approaching each other beyond a specified minimum gap. For a roller crusher in which only one roller is movable relative to the crusher frame, the movement blocking device may act only on the movable roller. The movement blocking device can be implemented, for example, by providing a mechanical blocking element that is arranged at the bearing seat of the movable roller in the support frame. However, as will be readily appreciated by a person skilled in the art, there are many alternative ways of providing such mechanical movement blocking. The movement blocking device can be constructed and arranged to be adjustable, thereby allowing the minimum gap to be adjusted.

[0124] According to one embodiment, the at least one scraper is positioned such that a minimum flange distance between the at least one scraper and the inner surface of the flange is 1-25 mm.

[0125] Preferably, the method further comprises positioning the scrapers such that a minimum flange distance between at least one scraper and an inner surface of the flange is at least 11 mm.

[0126] According to one embodiment, the at least one scraper is positioned such that the minimum flange distance between the at least one scraper and the inner surface of the flange is 15-20 mm.

[0127] This embodiment involves substantially the same advantages as those already described in detail with reference to the first aspect. In particular, by allowing at least 11 mm from the flange, it has been found that the risk of flange bending is significantly reduced. Flange bending is undesirable because it can cause material to slip out of the lateral crusher gap, thereby causing part of the material to bypass the roll crusher, ultimately resulting in the material output from the roll crusher not having the specified size distribution.

[0128] According to one embodiment, the structure and arrangement of the mobile blocking means limits the gap between the rollers to a minimum gap of at least 50 mm. It is also conceivable that the structure and arrangement of the mobile blocking means limits the gap between the rollers to a minimum gap of at least 55 mm, or at least 60 mm, or at least 65 mm, or at least 70 mm. As will be readily appreciated by a person skilled in the art, the minimum gap may depend on many factors, for example, the size of the crushing rollers and / or the size and material properties of the material to be crushed.

[0129] According to a fourth aspect of the present disclosure, there is provided a method for arranging a roller crusher having two substantially parallel rollers arranged to rotate towards each other in opposite directions and separated by a gap, each roller having two ends, the roller crusher comprising:

[0130] a flange attached to at least one end of one of the rollers,

[0131] The flange extends in the radial direction of the roller,

[0132] The height of the flange is higher than the outer surface of the roller, and

[0133] A moving blocking device constructed and arranged to limit the gap between rollers to a predetermined minimum gap, wherein the method comprises:

[0134] At least one scraper is positioned at the end of the flanged roller such that a minimum roller distance between the at least one scraper and the outer surface of the roller is less than or equal to the minimum gap.

[0135] The fourth aspect generally has the same advantages as the first aspect. However, it is emphasized that the method is applicable and suitable for any size-independent roller crusher. This means that the method is applicable and suitable for roller crushers of any roller size operating at any minimum gap setting and initial gap setting.

[0136] According to an embodiment of the fourth aspect, the method further comprises positioning at least one scraper at the end of the roller having the flange such that a minimum roller distance between the at least one scraper and the outer surface of the roller is in the range of 70-100% of the minimum gap.

[0137] According to an embodiment of the fourth aspect, the method further comprises positioning the scrapers so that a minimum flange distance between at least one scraper and an inner surface of the flange is 1-25 mm.

[0138] Preferably, the method further comprises positioning the scrapers such that a minimum flange distance between at least one scraper and an inner surface of the flange is at least 11 mm.

[0139] Preferably, the method further comprises positioning the scrapers such that a minimum flange distance between at least one scraper and the inner surface of the flange is 15-20 mm.

[0140] According to one embodiment of the method, the structure and arrangement of the movement blocking means limits the gap between the rollers to a minimum gap of at least 45 mm.

[0141] Similarly, corresponding to the first aspect of the disclosure above, each of the second, third and fourth aspects of the present disclosure will provide substantial advantages over prior art solutions.

[0142] The utility model provides a roller crusher, which has a frame and two substantially parallel rollers arranged to rotate toward each other in opposite directions and separated by a gap, each roller having two ends. The roller crusher comprises:

[0143] a flange attached to at least one end of one of the rollers,

[0144] The flange extends in the radial direction of the roller,

[0145] The flange has a height exceeding the outer surface of the roller,

[0146] wherein the roller crusher further comprises at least one scraper arranged at the end of the roller having the flange for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller, and

[0147] Each of the at least one scraper blades comprises a scraping element having a scraping surface, the scraping surface comprising polycrystalline diamond.

[0148] Preferably, the scraping element further comprises a wear-resistant material, and the polycrystalline diamond is at least partially embedded in the wear-resistant material.

[0149] Preferably, the wear-resistant material is one of the following: a ceramic material, a metal-ceramic composite material and a metal-matrix composite material.

[0150] Preferably, the scraping surface of the at least one scraper is arranged inclined relative to the normal to the inner surface of the flange and inclined such that the distance between the normal to the inner surface of the flange and the scraping surface decreases towards the flange.

[0151] Preferably, the at least one scraper has a surface facing the flange, the surface having an extension from the scraping element toward the rear end of the at least one scraper, wherein the at least one scraper is constructed and arranged so that the distance between the surface facing the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension.

[0152] Preferably, the at least one scraper has a surface facing away from the flange, the surface having an extension from the scraping element toward the rear end of the at least one scraper, wherein the at least one scraper is constructed and arranged so that the distance between the surface facing away from the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension.

[0153] Preferably, the scraping element comprises a front part and a rear part attached to each other, and wherein the front part has the scraping surface.

[0154] Preferably, the rear portion has a surface facing the flange and a surface facing away from the flange, the surfaces being substantially parallel to an inner surface of the flange.

[0155] Preferably, the at least one scraper is arranged in a lower part of the roll crusher.

[0156] Preferably, the at least one scraper is arranged such that a scraping surface of the at least one scraper is at least partially facing downwards to allow removed material to escape from the roller and the scraping surface by gravity.

[0157] Preferably, the at least one scraper has a fastening position, which is located at a certain distance from the outer surface of the roller, wherein the at least one scraper is arranged so that the scraping surface of the at least one scraper is located at a radial axis or is continuous with the radial axis, and the radial axis extends from the rotation axis of the roller and passes through the fastening position.

[0158] Preferably, the roll crusher further comprises at least one holding clamp for the at least one scraper, the at least one holding clamp being connected to the frame of the roll crusher at the fastening location of the at least one scraper.

[0159] Preferably, the at least one retaining fixture comprises at least one bracket and at least one wedge element, wherein the wedge element is constructed and arranged to attach the at least one scraper to the at least one bracket so that the angular position of the at least one scraper is offset in the rotation plane of the roller relative to the angular position of the at least one bracket.

[0160] Preferably, the roller crusher further comprises flexible holding means arranged to interconnect the at least one scraper and a frame of the roller crusher.

[0161] Preferably, the at least one scraper is at least two scrapers arranged successively to each other at the end of the roller having the flange for at least partially removing material accumulated on the outer surface at the flange and / or the end of the roller.

[0162] Preferably, the at least two scrapers in succession are arranged at equal distances from the flange and / or from the outer surface at the end of the roller.

[0163] Preferably, the at least two scrapers in succession are arranged at different distances from the flange and / or from the outer surface at the end of the roller.

[0164] Preferably, the at least two scrapers in succession are arranged with a decreasing distance from the flange and / or from the outer surface of the roller, seen from a front scraper to one or more successive scrapers.

[0165] Preferably, the at least two continuous scrapers comprise at least two subsets of at least two continuous scrapers, wherein the at least two continuous scrapers in each subset are arranged at the same distance from the flange and / or the roller surface, and wherein the at least two subsets of continuous scrapers are arranged at different distances from the outer surface at the end of the flange and / or the roller.

[0166] Preferably, said at least two subsets of consecutive scrapers are arranged at decreasing distances from said flange and / or the outer surface at the end of said roller, seen from a leading subset to one or more consecutive subsets.

[0167] Preferably, the roller crusher comprises two flanges attached to opposite ends of one of the rollers, and wherein the at least one scraper comprises a first subset of at least one scraper and a second subset of at least one scraper, the first subset and the second subset being each arranged on a respective end region of the roller having the two flanges.

[0168] Preferably, the roller crusher further comprises a remote material removal device, which is enabled to output a material removal beam towards a target area, wherein, at the end of the roller having a flange, the remote material removal device and the at least one scraper are arranged continuously with each other for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller.

[0169] Preferably, the target area of ​​the remote material removal device is located in front of the at least one scraper.

[0170] Other objects, features and advantages of the present disclosure will appear from the following detailed disclosure, the attached claims and the drawings.It should be noted that the present disclosure relates to all possible combinations of features.

[0171] In general, all terms used in the claims should be interpreted according to their ordinary meaning in the technical field, unless otherwise explicitly defined herein. Unless otherwise explicitly stated, all references to "a / an / the [element, device, component, method, step, etc.]" should be open to interpretation as references to at least one instance of the element, device, component, method, step, etc. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

[0172] As used herein, the term "comprising" and its synonyms do not exclude other additives, components, integers or steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0173] The present disclosure will be described in more detail with reference to the accompanying drawings, which show examples of currently preferred embodiments of the present disclosure.

[0174] Figure 1 It is a perspective view of a roller crusher according to the prior art.

[0175] Figure 2A yes Figure 1 Schematic top view of the two rollers of a roller crusher.

[0176] Figure 2B is a schematic top view of two rollers of a prior art roller crusher according to an alternative embodiment.

[0177] Figure 3A is a top cross-sectional view of a portion of a roll crusher according to the prior art.

[0178] Figure 3B is a side cross-sectional view of a portion of a roll crusher according to an embodiment of the present disclosure.

[0179] Figure 3C is a top view of a portion of a roll crusher according to an embodiment of the present disclosure.

[0180] Figure 4A is a partial cross-sectional side view of a roll crusher according to an embodiment of the present disclosure.

[0181] Figure 4B is a partial cross-sectional side view of a roll crusher according to another embodiment of the present disclosure.

[0182] Figure 4C is a partial cross-sectional side view of a roll crusher according to another embodiment of the present disclosure.

[0183] Figure 4D is a partial cross-sectional side view of a roll crusher according to another embodiment of the present disclosure.

[0184] Figure 5A It is shown Figure 4APartial cross-sectional side view of the relative sizes of a roll crusher's scraper.

[0185] Figure 5B It is shown Figure 4D Partial cross-sectional side view of the relative sizes of a roll crusher's scraper.

[0186] Figure 6 is a perspective view of a scraper and a holding fixture for mounting the scraper on a roll crusher according to one embodiment of the present disclosure.

[0187] Figure 7 According to one embodiment of the present disclosure Figure 6 A perspective view of three scrapers and their associated clamps mounted in series with one another on a flanged roller of a roller crusher.

[0188] Figure 8 is a perspective view of two pairs of continuous scrapers mounted on a common fixture on a roll crusher according to another embodiment of the present disclosure.

[0189] Figures 9A-9C is a partial cross-sectional side view of a roll crusher according to another embodiment of the present disclosure showing the use of an air knife to remove accumulated material at three consecutive time locations.

[0190] Fig.10 is a partial cross-sectional side view of a roll crusher according to another embodiment of the present disclosure.

[0191] Fig.11 is a partial cross-sectional side view of a roll crusher according to another embodiment of the present disclosure.

[0192] Fig.12 is a schematic side view of a roll crusher monitoring system.

[0193] Fig.13A is a perspective view of a material removal system including a mechanical scraper and an air knife according to an embodiment of the present disclosure.

[0194] Fig. 13B yes Fig.13A A perspective cutaway view of a material removal system.

[0195] Fig. 13C yes Fig. 13B A sectional side view of a portion of the roller with flanges is shown in FIG.

[0196] Fig.14A is a perspective view of a scraper for a roll crusher according to an embodiment of the present disclosure.

[0197] Fig. 14B is a top view of a portion of a roll crusher according to an embodiment of the present disclosure.

[0198] Fig. 14C yes Fig.14A Exploded view of the scraper.

[0199] Fig.15A is a perspective view of a scraper for a roll crusher according to an embodiment of the present disclosure.

[0200] Fig. 15B is a top view of a portion of a roll crusher according to an embodiment of the present disclosure.

[0201] Fig. 15C yes Fig.15A Exploded view of the scraper.

[0202] Fig.16 is a perspective view of two scrapers mounted on a common fixture on a roll crusher according to another embodiment of the present disclosure. DETAILED DESCRIPTION

[0203] The present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which presently preferred embodiments of the present disclosure are shown. However, the present disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to be thorough and complete and to fully convey the scope of the present disclosure to the skilled person. Like reference numerals refer to like elements throughout.

[0204] As described in the background section of this disclosure, by arranging flanges to the ends of the crushing rollers (such as Figure 2A , and discussed further below), or by providing a flange at each end of one of the grinding rollers (such as Figure 2A , and further discussed below), or by providing a flange on each grinding roller (such as Figure 2B The invention relates to a roller crusher which is a type of roller crusher which is used for the production of grinding rollers. The roller crusher ...

[0205] refer to Figure 1 , Figure 2A , Figure 2B , Figure 4A , Figure 4B , Figure 4C , Figure 4D , Figure 5A , Figure 5B , Figure 7 , Figure 8 , Fig.10 This is achieved completely or at least partly by a roller crusher 1 having two substantially parallel rollers 3, 4, 3', 4' arranged to rotate towards each other in opposite directions and separated by a gap G (see Figure 3A ), each roller having two ends. The roller crusher 1 further comprises a flange 36, 36' attached to at least one end of one of the rollers 3, 4, 3', 4', the flange 36, 36' extending in the radial direction of the rollers 3, 4, 3', 4' and having a height exceeding the outer surface 37, 37' of the rollers 3, 4, 3', 4'. The roller crusher 1 further comprises at least one scraper 100, 200, 300, 100a, 100b, 100c, 100d, 100t, which is arranged at the end of the roller 3, 4, 3', 4' having the flange 36, 36', for at least partially removing material accumulated on the flange 36, 36' and / or on the outer surface 37, 37' at the end of the roller 3, 5, 3', 4'.

[0206] Reference Figure 1 , Figure 2A , Figure 2B , Figure 4A , Figure 4B , Figure 4C , Figure 4D , Figure 5A , Figure 5B , Figure 7 , Figure 8 , Fig.10 , which is also achieved in whole or at least in part by a method of operating a roller crusher 1 for grinding particulate material, the roller crusher 1 having two substantially parallel rollers 3, 4, 3', 4' arranged to rotate towards each other in opposite directions and separated by a gap G, each roller having two ends, the roller crusher 1 further comprising a flange 36, 36' attached to at least one end of one of the rollers 3, 4, 3', 4', the flange 36, 36' extending in a radial direction of the roller 3, 4, 3', 4' and having a height exceeding an outer surface 37, 37' of the roller 3, 4, 3', 4'. The roller crusher 1 further comprises at least one scraper 100, 200, 300, 100a, 100b, 100c, 100d, 100t, which is arranged at the end of the roller 3, 4, 3', 4' having the flange 36, 36'. The disclosed method comprises at least one step of at least partially removing material accumulated on the flange 36, 36' and / or the outer surface 37, 37' at the end of the roller 3, 4, 3', 4' by at least one scraper 100, 200, 300, 100a, 100b, 100c, 100d, 100t.

[0207] For some exemplary embodiments, two or more scrapers 100, 100a, 100b, 100c, 100t are arranged to be arranged continuously with each other at the end of the roller 3, 4, 3', 4' having the flange 36, 36'. The arrangement of at least two scrapers 100, 100a, 100b, 100c, 100d, 100t arranged in series allows for extended operation time. The scraper 100, 100a, 100c that will first encounter the accumulated material (referred to herein as the "front scraper" or "first-in-line scraper") will suffer significant wear. Therefore, over time, the material of the front scraper 100, 100a, 100c will gradually wear away due to wear, thereby increasing the distance between the front scraper 100, 100a, 100c and the roller surface 37, 37' and / or the flange 36, 36'. As this wear process gradually occurs, the scraper 100, 100b, 100c, 100d, 100t arranged in series with and following the front scraper 100, 100a, 100c (referred to herein as the "second scraper" or "first following scraper") will be increasingly exposed to the accumulated material and will gradually take on more and more of the tasks that the front scraper 100, 100a, 100 would have performed if the scraper was new. This gradual transfer of scraping responsibility from the front scraper 100, 100a, 100c to the first following scraper 100, 100b, 100c, 100d, 100t thus allows to extend the operating time before the scraper has to be replaced, thereby reducing the downtime of the roll crusher 1 and helping to improve the overall efficiency of the plant.

[0208] However, the present disclosure should not be interpreted as being limited to providing two or more scrapers at the end of a roller with a flange. As will be described in detail below, the present invention concept will also be implemented by a scraper at the end of a roller with a flange. Figures 11 to 16 An example embodiment is described having only one scraper at the end of the flanged roller.

[0209] Figure 1A roller crusher 1 according to the prior art is shown. Such a roller crusher 1 comprises a frame 2 in which a first fixed crushing roller 3 is arranged in bearings 5, 5'. The bearing seats 35, 35' of these bearings 5, 5' are fixedly attached to the frame 2 and are therefore immovable. The second crushing roller 4 is arranged in bearings 6, 6' in the frame 2, which are arranged in the frame 2 in a slidably movable manner. The bearings 6, 6' can be moved in the frame 2 in a direction perpendicular to the longitudinal direction of the first and second crushing rollers 3, 4. Typically, guide structures 7, 7' are arranged on the first and second sides 50, 50' of the frame along the upper and lower longitudinal frame elements 12, 12', 13, 13' of the roller crusher 1. The bearings 6, 6' are arranged in movable bearing seats 8, 8', which can slide along the guide structures 7, 7'. Furthermore, a plurality of hydraulic cylinders 9, 9' are provided between the movable bearing blocks 8, 8' and first and second end supports 11, 11', which are provided near or at the first end 51 of the roller crusher 1. These end supports 11, 11' are attached to upper and lower longitudinal frame elements 12, 12', 13, 13' and also play a supporting role for the forces generated at the hydraulic cylinders 9, 9', as these hydraulic cylinders adjust the gap width and react to the forces generated at the crushing rollers due to the material fed to the roller crusher 1.

[0210] This type of roller crusher works according to a technique called inter-particle crushing. The crushing rollers 3, 4 rotate in opposite directions to each other, such as Figure 1 This is schematically indicated using arrows. The gap between the crushing rollers 3, 4 is adjusted by the interaction of the feed load and the hydraulic system which influences the position of the second crushing roller 4. Figure 1 As shown, and Figure 2A The rollers 3, 4 are shown from above, wherein one of the grinding rollers 3 further comprises flanges 36, 36' arranged at opposite ends of the grinding roller 3, wherein each flange 36, 36' has an outer edge which radially extends beyond the outer surface 37 of the roller body of the grinding roller 3 by a height H (see Figure 3A ) and is axially positioned on the outside of the roller body of the opposite grinding roller 4.

[0211] For example, another prior art roller crusher is disclosed in WO2013 / 156968, wherein each grinding roller with bearings is arranged in an interconnected arched frame part, wherein each interconnected arched frame part is pivotally connected to a base frame. The subject matter disclosed in the present disclosure is also applicable to such prior art roller crusher arrangement.

[0212] like Figure 3AAs shown, each flange 36 is arranged at one end of the roller 3 so that the inner surface 39 of the flange 36 is at a distance F from the end of the opposite roller 4. The distance F is necessary to avoid contact between the flange 36 and the roller 4, which may cause damage to the material. At the same time, the distance F should not be too large, because this increases the risk of material leaving the roller crusher through the gap formed thereby. The distance F can be achieved by mounting the flange 36 to the roller 3 via the spacer 15, as shown in FIG. Figure 3A The purpose of the flanges 36, 36' is to prevent material from leaving the gap at its ends, thereby forcing all material entering the roller crusher to be crushed through the crushing gap. Alternative embodiments of roller crushers with flanges are Figure 2B The only difference between these two embodiments is that Figure 2B The roller crusher in the embodiment has a flange 36 arranged on the second grinding roller 4' instead of the first grinding roller 3', which means that each grinding roller 3', 4' has a flange 36, 36'. As will be readily appreciated by a person skilled in the art, the technical effect of preventing the material from leaving the crusher 1, 1' at the end of the gap will be achieved equally well for both disclosed embodiments. Importantly, the disclosed utility model concept is equally applicable to both embodiments.

[0213] As mentioned before, the gap between the rollers 3, 4 can be adjusted. For the crushing operation, the roller crusher 1 is preset to have a certain distance between the rollers, the so-called starting gap G. Figure 3A As shown. The starting gap G is selected based on several different factors, such as the size of the roll crusher (i.e. the diameter of the grinding rollers), the desired characteristics of the crushed material, etc. The starting gap G can be in the range of 10 to 140 mm. However, typically, the starting gap G is in the range of 60 to 90 mm.

[0214] The roller crusher also includes a movement blocking device 20, which is constructed and arranged to limit the gap between the rollers to a minimum gap M. There are many different ways to provide such a movement blocking device known in the prior art, so they will not be discussed in detail herein. A common solution, namely Figure 1 The solution shown is to provide a pair of mechanical engagement elements 20a, 20b on the bearing seats 35, 35'. For some roll crushers and / or materials to be crushed, the minimum gap M may be relatively small, for example in the range of 10 to 30 mm. However, typically the minimum gap M is at least 45 mm. However, it is conceivable that the minimum gap is larger, for example at least 55 mm, or at least 60 mm, or at least 65 mm or at least 70 mm.

[0215] As initially mentioned, one problem with this type of grinding assembly is that material tends to form in the corner 40 between the outer surface 37 of the grinding roller 3 and the inner surface 39 of the flanges 36, 36' (see FIG. Figure 3A ) are piled up. Figure 1 and Figure 2A The roller crusher 1, this material is piled up 41 as Figure 3A Schematically shown, this is generally undesirable because it creates an increased local load in this area during operation, which may cause wear, damage and / or deformation on the opposing grinding roller 4 without flanges. In order to provide a solution to this problem, a device for removing at least a portion of this accumulated material 41 is provided. The present disclosure relates to two different such devices, a mechanical scraper and a remote material removal device. Reference will be made to Figures 2 to 3 to 4. Figure 8 Figure 14 to Fig.16 The mechanical scraper will be discussed, and then the remote material removal device will be discussed with reference to Figures 9 to 13.

[0216] Figure 3B A mechanical scraper 100 according to an embodiment of the present disclosure is shown in a front view. The mechanical scraper 100 is attached to a roller crusher, such as in a frame or other supporting feature, but is shown here separately relative to the crushing roller to enhance clarity. The mechanical scraper 100 includes two wear elements 102a, 102b arranged at the ends of the scraper 100 so as to define a scraping surface 104 that is generally facing the material to be removed. The statement "generally facing the material to be removed" means that the scraping surface 104 is basically arranged tangentially to the roller surface. The wear elements 102a, 102b are attached to the scraper body 103 (at Figure 3B Not visible in the front view, but in Figure 3C ). Figure 3C As shown, Figure 3C Shown in top view Figure 3B The scraper 100 together with a portion of the roller 3 with the flange 36, when rotating toward the scraper 100 as shown by the arrow, which indicates the tangential speed of the rotating roller 3, the wear elements 102a, 102b can be arranged on the scraper body 103 so that the scraping surface 104 of the scraper 100 is arranged to be inclined relative to the normal N of the inner surface 39 of the flange 36, and the inclination is such that the distance L1 between the normal N of the inner surface 39 of the flange 36 and the scraping surface 104 decreases toward the flange 36. The normal N is defined as a line orthogonal to the plane defined by the inner surface 39 of the flange 36. This allows the material, once scraped off, to be more easily transported away from the corner 40 between the inner surface 39 of the flange 36 and the outer surface 37 of the roller 3, thereby facilitating an efficient material removal process.

[0217] The nature of the material accumulation 41 and the speed at which the at least one mechanical scraper 100 encounters the material accumulation 41 tends to cause the material removal to be substantially impact driven. Thus, rather than the scraper forming a notched depression in the material accumulation over time, a large surface portion of the material accumulation 41 breaks off almost instantaneously when encountering the scraper. Figure 3B and 3C Schematically shown. It has been found that the remaining portion of the material accumulation 41 presents a relatively uniform outer surface. It is not necessary to completely remove the material accumulation 41. Preferably, only a portion of the accumulation 41 should be removed. Partial removal of the material accumulation 41 will reduce the overall wear of the scraper 100 because the scraper 100 is subject to a significantly lesser degree of wear when it is positioned further away from the roller surface 37. It has been recognized that a preferred position for the scraper 100 may be when the scraper 100 is positioned so that the minimum roller distance S1 between each of the at least one scraper 100 and the outer surface 37 of the roller 3 is at least 70% of the minimum gap M. The minimum roller distance S1 is as shown in FIG. Figure 3B It should be noted that for Figure 3B In the exemplary embodiment shown, the scraper 100 is constructed and arranged so that the distance between the scraper 100 and the outer surface 37 of the roller 3 is substantially constant. This means that the minimum roller distance S1 will coincide with the substantially constant distance. However, for other undisclosed embodiments, the scraper may be constructed and / or arranged so that the distance between the scraper 100 and the outer surface 37 of the roller 3 varies. For such embodiments, the minimum roller distance S1 will be the shortest distance between the scraper and the outer surface 37 of the roller 3. At this position of the scraper 100 with the minimum roller distance S1, the roller crusher 1 can operate for an economically acceptable period of time before the scraper 100 has worn to the extent that the distance between the scraper 100 and the outer surface 37 of the roller 3 will become close to the minimum gap M, and the scraper 100 must be repositioned or replaced. Figure 3B As shown, the scraper 100 is located at the minimum flange distance S2 from the inner surface of the flange 26. Figure 3A and Figure 3BAs shown, this minimum flange distance S2 is greater than the distance F between the roller 4 and the inner surface 39 of the flange 36. This may seem a bit surprising, because it can be expected that the scraper 100 may miss removing the material that needs to be removed in order to completely avoid contact between the roller 4 and the material accumulation 41. However, positioning the scraper 100 closer to the flange 36 is associated with other disadvantages. First, it increases the risk of the scraper 100 being damaged by the flange 36 and / or the material accumulation 41 on the flange 36, which increases as the distance to any moving surface decreases. Secondly, this increases the risk of damaging the flange 36 itself. By positioning the scraper 100 at the minimum flange distance S2 greater than the distance F, a reasonable compromise is obtained. A sufficient amount of material is removed from the accumulated material 41 at the flange 36, while keeping the scraper 100 at a safe distance from the flange, which results in an extension of both the scraper life and the flange life. Preferably, the scrapers 100 are positioned so that the minimum flange distance S2 between at least one scraper 100 and the inner surface 39 of the flange 36 is 1-25 mm. More preferably, the scrapers 100 are positioned so that the minimum flange distance S2 between at least one scraper 100 and the inner surface 39 of the flange 36 is at least 11 mm. It has been found that at this distance, the risk of flange damage is significantly reduced. Needless to say, flange bending is undesirable because it can cause material to slip out of the crusher gap at the side, resulting in part of the material bypassing the roll crusher, ultimately resulting in the material output from the roll crusher not having the specified size distribution.

[0218] Scraper 100 only Figure 3B and 3C 4 to 5, in order to determine the preferred position of the scraper 100 relative to the roll crusher 1, or more specifically, relative to the roll surface 37 and / or flange 36. Figure 8 , the scraper (such as Figure 3B How to use the scraper 100 in combination on the roll crusher.

[0219] FIG. 4A to FIG. 4D Four different example embodiments of roll crusher scraper assemblies are shown. For each scraper included in these assemblies, the above reference Figure 3B The preferred positioning of the scraper 100 described in FIG. 1 may apply. When describing the example embodiments, attention will be directed to the differences in positioning and other characteristics between the various scrapers.

[0220] Figure 4AA scraper assembly 1000 according to a first exemplary embodiment is shown. The scraper assembly 1000 comprises two scrapers 100a, 100b which are arranged in series with one another at the end of a roller 3 having a flange 36. The scrapers 100a, 100b are positioned relative to the roller 3 such that the scrapers are located at the same or substantially the same minimum distance from the roller surface 37 (in other words: the same minimum roller distance S1, see Figure 3B ). In addition, the scrapers 100a, 100b are positioned so that the scrapers are located at the same or substantially the same minimum distance from the flange 36 (in other words: the same minimum flange distance S2, see Figure 3B ). Thus, for the scraper assembly 1000, the front scraper, i.e., scraper 100a, will be the only scraper that actually performs any material removal, at least for the first period of time after the scraper assembly 100 is installed. Figure 4A In the figure, only the front scraper 100a is used to remove the material 60a. In case the front scraper 100a fails, the scraper 100b will serve as a pure spare scraper. This is advantageous because it prolongs the operating time before the crusher must be shut down for replacement.

[0221] Over time, the wear elements 102a, 102b of the front scraper 100a will gradually wear away, effectively moving the scraper "away" from the roller surface 37 and / or the inner surface 39 of the flange 36. This wear process will result in more and more material of the material accumulation 41 not being removed by the first scraper 100a, resulting in an increase in the thickness of the material accumulation 41 advancing toward the second scraper 100b. Since the second scraper 100b is initially positioned in the same relative position relative to the roller surface 37 and the flange 36 as the front scraper 100a, it has been protected from wear by the front scraper 100a up to this point. This means that the second scraper 100b will still maintain its original minimum distance to the roller surface 37 at this time. Therefore, the second scraper 100b can now be used to remove excess material that the worn front scraper 100a can no longer remove. In this way, as it wears, the second scraper 100b will become increasingly important to the overall material removal of the scraper assembly 100. Thus, the scraper 100b initially functions as a pure standby scraper and eventually functions as a scraper in operation. The front scraper 100a and the second scraper 100b may each be mounted on a respective holding fixture 110a, 110b, which in turn may be mounted on a support structure 150, which may be part of the frame of the roll crusher, or a bracket or support element attached to the frame. The holding fixture will be described in more detail later with reference to FIG. 5.

[0222] Figure 4BA scraper assembly 2000 according to a second exemplary embodiment is shown. The scraper assembly 2000 differs from the first exemplary embodiment 1000 only in that the scrapers 100a and 100b are arranged at different minimum distances from the roller surface 37 (in other words: they have different minimum roller distances S1), wherein the minimum roller distance S1 of the second scraper 100b is smaller than the minimum roller distance S1 of the front scraper 100a. As will be readily understood by a person skilled in the art, this means that the front scraper 100a and the second scraper 100b will remove material already from the beginning in the first operating period. This is Figure 4B In the example, only the removal of material 60a by the front scraper 100a and the removal of material 60b by the second scraper 100b are illustrated. Therefore, the second example embodiment will share the technical effect presented by the first example embodiment after the first time period. The front scraper 100a and the second scraper 100b are preferably at a position with the same or substantially the same minimum distance from the inner surface of the flange (i.e., the same as the first example embodiment). However, it is also conceivable that the second scraper 100b is positioned so that the minimum distance between the scraper 100a and the inner surface 39 of the flange 37 is greater than the corresponding distance of the second scraper 100b (i.e., the minimum flange distance S2 of the front scraper 100a is greater than the minimum flange distance S2 of the second scraper 100b). As is readily understood by those skilled in the art, for different minimum roller distances S1, this relative positioning provides similar technical effects as those already described.

[0223] Figure 4C FIG. 3 shows a scraper assembly 3000 according to a third exemplary embodiment. The scraper assembly 3000 differs from the second exemplary embodiment only in that the scrapers 100a and 100b are followed by other scrapers arranged in series, and the third scraper 100c is directly followed by a trigger scraper 100t. Figure 4C As shown, the first three scrapers 100a-c are arranged at different minimum distances from the roller surface 37 (in other words: they have different minimum roller distances S1), and the minimum roller distance S1 of each consecutive scraper in the scraper row starting from the front scraper 100a gradually decreases. As will be readily understood by those skilled in the art, this means that all three scrapers 100a-c will remove material from the start of operation. This is Figure 4CAs shown in , the front scraper 100a removes material 60a, the second scraper 100b removes material 60b, and the third scraper 100c removes material 60c. The trigger scraper 100t is arranged at the end of the continuous scraper column and thus acts as a rear scraper. The trigger scraper 100t is arranged at the maximum allowable distance T from the roller surface 37 and is configured to provide a trigger signal in response to contacting the material accumulation 41. In the exemplary embodiment, this is achieved by a strain gauge 96 mounted on the holding fixture 110t. Therefore, during normal operation of the roller crusher, the trigger scraper 100t does not contact the material accumulation 41. However, over time, the scrapers 100a-c will gradually wear, so the material accumulation 41 will gradually become thicker and thicker. When the accumulated material 41 has reached the maximum allowable distance T, it will contact the trigger scraper 100t. This will generate mechanical strain in the holding fixture 110t, which will be reflected in the signal output from the strain gauge 96. Monitoring this signal allows determining when the "active scrapers" (i.e., scrapers 100a-c) have all used up their useful time and need to be replaced. Thus, the trigger signal from the strain gauge 96 can be used to determine when the machine must be shut down to replace the scraper. Although it is preferably not intended to do so, the trigger scraper 100t itself is still a scraper. This means that if the roller crusher is running for a period of time after the trigger scraper 100t first induces a signal to stop the crusher, the trigger scraper 100t will provide scraping. Therefore, the trigger scraper 100t is not just a sensor - it is also an additional backup scraper. In order to prevent damage to the rollers and / or flanges, the maximum allowable distance T can be selected so that the roller crusher can also run for a period of time after starting scraping with the trigger scraper 100t. The term "trigger scraper" should not be interpreted as referring to a special type of scraper itself. The scraper 100t can be the same as any other scraper disclosed herein, such as scrapers 100a, 100b and 100c. Rather, the term is used to identify a specific scraper of the at least one scraper that is configured to act as a sensing device to provide information about material accumulation 41. This can be achieved in different ways as long as the mechanical interaction between the accumulated material and the triggered scraper is converted into an output signal.

[0224] Figure 4DA scraper assembly 4000 according to a fourth exemplary embodiment is shown. The scraper assembly 4000 differs from the second exemplary embodiment in that the scrapers 100a and 100b are here mounted on a common holding fixture 410a, which together with the scrapers 100a and 100b forms a first subset 400a of scrapers, and the scraper assembly 4000 also contains a second subset 400b of scrapers including scrapers 100c and 100d, which second subset 400b is arranged consecutively with the first subset 400a. Each common holding fixture 410a, 410b can be mounted on a support structure 450, which can be part of the frame of the roller crusher, or a bracket or support element attached to the frame. Figure 4D As shown, a pair of scrapers of a subset is arranged at an equal minimum distance S1 from the roller surface. However, the minimum distance S1 of the first subset 400a is greater than the minimum distance S1 of the second subset 400b. As will be readily appreciated by those skilled in the art, during the first time period or crushing operation, the first scraper 100a of the subset 400a and the first scraper 100c of the subset 400b will perform material removal in the same manner as previously described for the scraper assembly 2000 of the second exemplary embodiment. However, the difference between the fourth and second exemplary embodiments is that the fourth exemplary embodiment will provide a spare scraper in the form of a second column of scrapers in each subset (i.e., a scraper 100b for the first subset 400a and a scraper 100d for the second subset 400b). As the scrapers 100a and 100c have worn, the scrapers 100b and 100d will gradually start to work. Therefore, the fourth exemplary embodiment provides backup and shared scraping. Another difference between the fourth example embodiment and the previously described example embodiments is that each subset of scrapers 400a, 400b constitutes its own unit. Specifically, the front scraper 100a and the second scraper 100b of the first scraper subset 400a can be mounted on a common fixture 410a, and the scrapers 100c and 100d of the second scraper subset 400b can be mounted to the common fixture 410b. The importance of the common holding fixture relative to the single holding fixture of the previous example embodiments will be described below.

[0225] The four exemplary embodiments described above constitute different combinations or arrangements of a single utility model aspect, such as using two or more scrapers, using spare scrapers, using scrapers together to share scraping operations, etc. Those skilled in the art will appreciate that many other combinations of these utility model aspects are also possible. For example, within the scope of the claims, a trigger scraper can be added to any one of the other exemplary embodiments or any other exemplary embodiment. As another non-limiting example, two or more scrapers can be arranged to be equal to the minimum distance from the roller surface (minimum roller distance S1), but different from the minimum distance from the flange (minimum flange distance S2). The scraper can also be positioned at different angular positions relative to the axis of rotation of the roller 3. It is conceivable that the scraper is positioned substantially at any angular position along the roller except for the gap. However, preferably, the scraper is arranged at the bottom of the roller crusher. This means that the scraper is arranged below the horizontal plane associated with the rotation axes R1 and R2 of the two rollers 3 and 4. Even more preferably, the scraper is arranged so that the scraping surface of the scraper is at least partially facing downward to allow the removed material to leave the roller and the scraping surface by gravity. Preferably, the scraper is arranged at approximately 6 to 9 o'clock, 7-9 o'clock or 7-8 o'clock of the roller 3 when the roller 3 is viewed from the side showing clockwise rotation.

[0226] Now refer to Figure 5A and Figure 5B Describe the scraper blade holding fixture in detail. Figure 5A Shows Figure 4A Each scraper 100a, 100b can be attached to a corresponding retaining fixture 110a, 110b, which in turn can be attached to the support structure 150 by fasteners 120a, 120b at a fastening position P2, which is located at a distance from the outer surface 37 of the roller 3. Figure 5A As shown, the holding clamps 110a, 110b are shaped in a specific manner. In particular, each scraper 100a, 100b is arranged relative to the roller crusher 1 so that the position P1 of each scraping surface 104 of the scraper 100a, 100b is located at or continuous with the radial axis A, which extends from the rotation axis R1 of the roller 3 and passes through the corresponding fastening position P2. By this arrangement, it is ensured that any unintentional movement of the scraper 100a, 100b due to strong impact forces generated, for example, by interaction with the accumulated material 41 will force the scraper to move away from the roller surface 37. This is in Figure 5AThe scraper 100b indicated by the dotted line in the figure shows how the disconnected retaining fixture 110b and its scraper 100b pivot clockwise after being subjected to a strong impact force, thereby pivoting outward around its fastening position P2. This process means that the fastener 120b breaks at the fastening position P2. This represents a conceivable way to achieve the preferred effect, that is, intentionally designing a weak point at the fastening position P2. The retaining fixture does not have to be fixedly attached at the fastening position P2. It is also conceivable that the retaining fixture is pivotally attached at the fastening position P2. In order to ensure that the scrapers 100a, 100b remain in their predetermined positions during operation, this pivotably arranged scraper can be mechanically locked in the predetermined position by a locking system (e.g., gears, cams, etc.). An example will be given below.

[0227] Figure 5B Shows Figure 4D The scraper assembly 4000 shown in . As previously mentioned, scrapers 100a and 100b can be mounted on a common retaining fixture 410a, which together with scrapers 100a, 100b forms a first subset 400a of scrapers. In the same way, scrapers 100c and 100d can be mounted on a common retaining fixture 410b, which together with scrapers 100c, 100d forms a second subset 400b of scrapers. Each common retaining fixture 410a, 410b can be attached to a support structure 450 at a corresponding fastening position P3. However, the fastening for this embodiment is different from the fastening for scraper assembly 3000. Instead of being rigidly fastened by fasteners 120a, 120b, retaining fixtures 410a, 410b are pivotally fastened and biased toward the working position. This is achieved by fasteners 420a and 420b, respectively. The size of the bias should keep the scraper 100a-d in the working position until a predetermined threshold force is reached. Similarly, such a predetermined threshold force is set to ensure that the outer surface of the flange and / or the roller end will not be damaged by the collision between the scraper and the non-removable material. The bias can be achieved by a spring. It is also possible to consider using a non-biased pivotable fastener combined with a torque limiter. For such an embodiment, the retaining clamp will appear to be rigidly attached to the roller crusher until the scraper has been subjected to a force exceeding a specific threshold force at which the torque limiter is activated, and the retaining clamp is allowed to swing the scraper away from the roller surface. The torque limiter can be combined with a biasing device (e.g., a spring).

[0228] Discussing the second subset 400b, since more than one scraper is attached to the same common holding fixture, the holding fixture must preferably be designed so that the position P1 of the two scrapers 100a, 100b is located or continuous with the radial axis A, which extends from the rotation axis R1 of the roller and passes through the common fastening position P3. This means that it must be ensured that the scraping surface 104 of the scraper 100a and the scraper 100b are both located at or continuous with the radial axis A. This will ensure that any unintentional movement of the scrapers 100a, 100b due to strong impact forces, for example, generated by interaction with the accumulated material 41, will force the scrapers to move away from the roller surface 37. This is in Figure 5B The second subset of scrapers 400b indicated by dashed lines in FIG. 4 shows how the disconnected first subset of scrapers 400b pivots clockwise about their respective common fastening position P3 and thus pivots outwards after being subjected to a strong impact force.

[0229] Figure 6 The described scraper 100 is shown together with a retaining fixture 510 according to another example embodiment. The retaining fixture 510 can include a square beam 512, which is constructed and arranged to be attached to the support structure of the roll crusher. Attached to the square beam 512 is a bracket 514, which exhibits an attachment surface 516 with a through hole 518. The scraper 100 can be attached to the bracket 518 via a wedge element 520. The wedge element 520 has a first surface 522 and a second surface 524, the first surface 522 is configured to be attached to the attachment surface 516 by a fastener (such as a bolt and screw), and the body 103 of the scraper 100 is attached to the second surface 524, such as by welding. A chain 526 interconnects the wedge element 520 with the square beam 512 and acts as an additional safety measure. In the event that a sudden impact force would break the attachment between the wedge element 520 and the bracket 514, the chain 526 will prevent the scraper 100 and the wedge element 520 from falling into the material output section of the roll crusher (not shown). This is advantageous because it prevents damage to the underlying structure, such as conveyor belts, screens, chute surfaces, etc.

[0230] Figure 7 A scraper assembly 6000 is shown, which consists of three scrapers 100 mounted on the reference Figure 6 The three scrapers 100 are arranged successively to each other here, and the scraper assembly 6000 is intended to be arranged in the same manner as previously described. FIG. 4A to FIG. 4DThe same arrangement is arranged along the roller with flanges for at least partially removing material accumulated on the flanges and / or on the outer surface of the roller ends. Each holding fixture 510 is mounted to the roller crusher by means of a corresponding plate 620, which can be attached to the frame element 610. During installation, the position of each scraper 100 is adjusted by carefully adjusting the plate 620 before attaching it to the frame element 610. The relative position between each scraper and the roller surface and / or flange can be adjusted as described above with reference to Figures 4A to 4D Thus, it is conceivable that the scrapers 100 of the scraper assembly 6000 have an equal minimum roller distance S1 from the roller surface 37, but may alternatively have different minimum roller distances S1 from the roller surface 37. In the same manner, it is conceivable that the scrapers 100 of the scraper assembly 6000 have an equal minimum flange distance S2 from the inner surface 39 of the flange 36, but may alternatively have different minimum flange distances S2 from the inner surface of the flange.

[0231] Figure 8 A scraper assembly 7000 according to another example embodiment is shown. The scraper assembly 7000 includes four scrapers 100 arranged in pairs along both ends of a roller 3 having a double flange 36. Each scraper 100 in a pair of scrapers is arranged continuously with the other scraper 100 in the pair of scrapers, and can be installed according to any of the aforementioned combinations or any undescribed combination within the scope of protection of the claims. In particular, a pair of scrapers 100 can have substantially the same minimum roller distance S1 and / or minimum flange distance S2, or can have different minimum roller distances S1 and / or minimum flange distances S2. The scrapers 100 are each mounted to a support structure 710, which in turn is mounted to the frame of the roller crusher. As will be readily appreciated by those skilled in the art, the scraper assembly 7000 is constructed and arranged to be located at approximately 6 to 9 o'clock of the roller 4 when the roller 4 is viewed from the side showing clockwise rotation.

[0232] 9A to 9CA scraper assembly 8000 according to another example embodiment is shown. The scraper assembly 8000 includes a scraper 100 and an air knife 800, which are arranged in succession to each other at the end of a roller 3 having a flange 36 for at least partially removing material accumulated on the flange 36 and / or on the outer surface 37 at the end of the roller 3. From here on, the scraper 100 will be referred to as a "mechanical scraper 100" in this document to clearly distinguish it from the air knife 800, which also removes material but not through mechanical interaction (the air knife can be regarded as a non-contact scraper). The air knife 800 is constructed and arranged to at least intermittently direct an air plume 820 of pressurized air towards a target area 822 located at the outer surface 37 at the end of the roller 3. The air plume 820 provides sufficient air impact at the target area 822 for at least partially removing the material accumulated thereon. The term "intermittently" herein means that the air knife directs the plume to the target area at irregular or regular intervals during operation of the roll crusher. This means that the air knife may not be in continuous or steady operation. However, for some applications and some embodiments of the remote material removal device, the device may be in continuous or steady operation.

[0233] The air knife 800 includes a body 802 having an elongated extension. For the present exemplary embodiment, the body 802 is arranged substantially horizontally in the lower part of the roll crusher. Pressurized air is supplied to the air knife 800 through a duct 806, which is connected to a high pressure air source 98. The air knife 800 will be described in more detail later. As will be readily appreciated by those skilled in the art, the efficiency of material removal will depend on the distance between the outlet nozzle of the air knife and the target area 822 and the angle formed between the air plume 820 and the target area 821. The distance may be in the range of 50–500 mm from the target area 822.

[0234] Air knife 800 is an example of a fluid jet knife, which is an example of a class of devices that can remove material from a distance. These devices are referred to herein as "remote material removal devices." These devices are configured to output a material removal beam toward a target area, and the material removal beam interacts with the material present in the target area to at least partially remove the material. Depending on the type of remote material removal device, the material is removed through different processes, such as mechanical impact, heating, ablation, exothermic reaction, etc. Fluid jet knives create high-speed fluids for us to remove material through impact. Other examples of remote material removal devices are lasers, which can be used to remove material through laser heating and material ablation. Although the exemplary embodiments disclosed herein focus primarily on air knives, the concepts of the present invention should not be construed as limited thereto, and it is contemplated that in any exemplary embodiment, any suitable alternative remote material removal device may be used in place of the air knife.

[0235] like Fig.9A As shown, the target area 822 of the air knife 800 is located in front of the mechanical scraper 100. This means that when in operation, the accumulated material 41 at the flange 36 will encounter the target area 822 of the air knife 800 before encountering the mechanical scraper 100. Although the present inventive concept is not limited to this particular order, it is considered to be a preferred order because the air knife 800 can be used to remove extra hard and / or excess accumulated material 41 at the flange 36 before the material hits the mechanical scraper 100. As will be readily appreciated by those skilled in the art, this reduces the risk of structural damage to the mechanical scraper 100.

[0236] The advantage of the air knife 800 over the mechanical scraper 100 is that the air knife 800 allows for control. This advantage also applies to other remote material removal devices, such as fluid jet knives and lasers. Thus, the air knife can be used only at the specific location where it is most needed. To this end, the air knife 800 can be connected to a control system. The control system can be a roll crusher control system 80 (such as Fig.12 ), a control system of the scraper assembly 8000, or even an external system (such as a general control system of the plant), or forms part of such systems. When the roll crusher is started with clean rolls 3, 4, there is no accumulated material 41 at the flanges 36, 36', and during the first time period of the crushing operation, material will accumulate at the corner transition between the roll surface 37 and the flange 36, thereby forming a material accumulation 41. During the first time period after startup, such as the first hour of operation, the material accumulation 41 will be relatively soft throughout the depth of the material, so that the mechanical scraper 100 will be able to effectively remove any excess accumulation at an acceptable wear rate of the mechanical scraper 100 and an acceptable level of mechanical stress on the retaining clamp 110, thereby maintaining the mechanical scraper 100 in place relative to the roll crusher. This period of time and the operation of the scraper assembly 8000 during this period are as shown. Fig.9A shown.

[0237] After a long period of continuous operation of a roll crusher, the material buildup 41 will become increasingly compacted, hardening throughout the depth of the material. This will increase the wear rate of the mechanical scraper 100 and the level of mechanical stress on the retaining fixture 110, increasing the risk of damage to the mechanical scraper 100. This problem can be addressed by removing the builtup material with an air knife 800 before the builtup material becomes too hard. By applying an air plume 820 to a target area 822 located at the end of the roller 3 having the flange 36, the air plume 820 can partially or completely remove the material buildup 41 located there. By removing the material buildup 41, the wear life of the mechanical scraper 100 and its retaining fixture 110 will be increased, providing a more reliable system for retaining the builtup material 41 within acceptable levels at the flange. This Fig. 9B and9C FIG. 4 shows the initial stage of substantially completely removing the particle accumulation 41 using the air knife 800 ( Fig. 9B ) and the final stage ( Fig. 9C ).like Fig. 9C As shown, the removed material 60a may be directed into a dedicated container 99. The container 99 may be advantageous because it allows reducing the dust cloud formed at the roll crusher when using an air knife.

[0238] The air knife 800 may be operably connected to a control unit. In an exemplary embodiment, the air knife 800 is operably connected to a control unit 80 of a roll crusher. Fig.12 As shown. The air knife 800 can be controlled in different ways. For example, the air knife 800 can be turned on within a predetermined time range, such as every 3, 4 or 5 revolutions of the roller 3. Alternatively, the air knife 800 can be turned on at a time position determined by the roller crusher monitoring system data, which is related to the accumulation level of material accumulated on the outer surface 37 of the flange 36 and / or the end of the roller 3. Such roller crusher monitoring system data can be obtained by the monitoring system 90 of the roller crusher, which will be further described later. It is also preferred to turn on the air knife 800 for a period of time before the roller crusher is shut down to allow the material accumulated on the outer surface 37 of the flange 36 and / or the end of the roller 3 to be removed. By removing the accumulated accumulation material 41 before shutting down, it will be easier to maintain the mechanical scraper (such as the scraper 100), such as replacing, adjusting or inspecting the mechanical scraper.

[0239] In the concept of the present invention, there are several conceivable combinations of mechanical scrapers and remote material removal devices. Figure 8 Any combination of mechanical scrapers discussed may be combined with a remote material removal device such as an air scraper. By way of non-limiting example only, Fig.10 FIG. 8 shows a scraper assembly 8000' according to an alternative exemplary embodiment. The scraper assembly 8000' differs from the scraper assembly 8000 of FIG. 9 in that, first, the scraper assembly 8000' has three scrapers 100a, 100b and 100t arranged in series, instead of a single mechanical scraper, wherein the first two scrapers 100a, 100b are working scrapers and the last scraper 100t is a trigger scraper. The function of the trigger scraper 100t has been described with reference to FIG. Figure 4C The arrangement of the two working scrapers 100a, 100b is the same as that in the previous reference. Figure 4AThe description is similar, that is, the minimum roller distance S1 of scraper 100a is substantially the same as the minimum roller distance S1 of scraper 100b. Another difference is that the remote material removal device in the scraper assembly 8000' is not an air knife, but a high-energy laser. For the exemplary embodiment, a high-energy continuous wave CO2 laser is used, but other preferably pulsed high-power lasers are also conceivable. The material removal beam constituting the laser beam 820' is thus directed to the target area 822' and the accumulated material is removed by laser ablation. It may be necessary to move (i.e., scan) the laser beam during operation to fully remove the material accumulation. This can be achieved by an optical system based on lenses and / or mirrors and is known in the art.

[0240] Fig.11 Another non-limiting example embodiment is shown, namely a scraper assembly 8000". Scraper assembly 8000" differs from scraper assembly 8000 in that the remote material removal device is a water jet knife 800", connected to a pressurized water supply 98", the water jet knife 800" is configured to output a water spray 820" to a target area 822", and the relative position of the scraper 100 and the water jet knife 800" on the roller crusher is within the area 9 to 12 o'clock of the roller when the roller is viewed from the side showing clockwise rotation. An advantage of using a water jet knife as compared to an air jet knife can be reduced dust formation. An advantage of this position can be that material will be more easily removed from the roller crusher because the direction of impact is generally downward - opposite to the substantially horizontal impact direction of the previously described embodiments.

[0241] Fig.12 A monitoring system 90 for a roller crusher is shown, here taking a scraper assembly 8000 as an example. In this example, the crushing roller 3 has a flange 36, where the deposited material 41 has accumulated as described in detail above. The monitoring system 90 may include a controller connected to a series of sensor peripherals. Fig.12In the example embodiment shown, the control unit 80 of the roll crusher also acts as the control unit of the monitoring system 90. In particular, these sensor peripherals may include a first monitoring camera 92 arranged so that the accumulated material 41 is within the field of view. By analyzing the signals sent from the first monitoring camera 92, the level of material accumulation can be inferred by the control system 80. By allowing the first monitoring camera 92 to observe the flange 36, it is also conceivable to infer the degree of flange deformation based on the analysis of the signals from the first monitoring camera 92. The monitoring system 90 may also include a second monitoring camera 93 arranged so that the spray plume of the scraper 100 and / or the air knife 800 is within the field of view. By analyzing the signals sent from the second monitoring camera 93, the control system 80 may infer the condition of the scraper 100 and / or the air knife 800. The monitoring system 90 may also include a plurality of strain gauges 94 arranged on the flange 36. By analyzing the signals transmitted by the strain gauges 94, the condition of the flange 36 can be monitored. The strain gauges 94 may be arranged to transmit the signals wirelessly. The monitoring system 90 may also include a strain gauge 96 mounted on the scraper blade 100. By analyzing the signal transmitted by the strain gauge 96, the condition of the mechanical scraper blade 100 may be monitored. Although shown here as being mounted on the scraper blade 100, it is also contemplated that the strain gauge may be provided on the holding fixture 110.

[0242] FIG. 13A to FIG. 13C A scraper assembly 9000 according to another example embodiment is shown. The scraper assembly 9000 is similar to the scraper assembly 8000 described previously and is based on a combination of an air knife and a mechanical scraper. However, the scraper assembly 9000 also includes some features, which will now be discussed in detail.

[0243] The scraper assembly 9000 comprises a scraper 900 having two wear elements 904a, 904b. The scraper 900 is mounted to a wedge-shaped element 920 which is attached to a bracket 914 by bolts. The bracket 914 is attached in a beam 912 which can be mounted on the frame of the roll crusher. Openings are provided in the wedge-shaped element 920 and the bracket 914 which form through openings 921 in the elements when they are mounted together. The purpose of the through openings 921 is to allow the air plume 820 from the air knife 800 to pass through the structure. The air injector 800 is arranged with its air nozzle 804 located just behind the through openings 921. As Fig. 13B and Fig. 13CAs best shown, the air knife 800 includes a conduit 806 that fluidly connects the air nozzle 804 with an air inlet 808 located at the opposite end of the air knife body 802. Immediately downstream of the air inlet 808, a valve system 810 is provided. The valve system 810 can be controlled from a remote location, such as by the control system described in detail above. The air knife 800 is attached to the support structure 960 of the roll crusher by a beam 926.

[0244] The scraper assembly also includes a wear protection device 950 for protecting the air knife 800. For the exemplary embodiment, the wear protection device includes two separate features: First, the body 802 of the air knife 800 is protected by a wear protection member 952 disposed on the top of the body 802. The wear protection member 952 has an inclined top surface for allowing falling material to deflect from the air knife 800. Second, the air nozzle 804 of the air knife 800 is protected by a bracket 914 and a wedge-shaped element 920. Since the elements are disposed very close to the air nozzle 804, they will act as a shield for the air nozzle 804, thereby protecting the air nozzle from foreign objects such as falling broken material. The through opening 921 allows the air plume 820 to pass through the wear protection structure, such as Fig. 13C Best shown.

[0245] FIG. 14A to FIG. 14C A scraper 200 according to a second exemplary embodiment of the present disclosure is shown. The scraper 200 may be used in place of the scraper 100 already described, which replaces the scraper in any one of FIGS. 4 to 13 . Fig. 14B In FIG. 3 , the scraper 200 is shown in a predetermined position at the flange 36 of the roller 3 . The black arrow indicates the tangential speed of the rotating roller 3 .

[0246] The scraper 200 includes a scraping element 210. The scraping element 210 has a scraping surface 204. FIG. 14A to FIG. 14C As shown, the scraping surface 204 is used for the scraper 200 defined on a single element, namely the scraping element 210. This is different from the scraper 100 of the first exemplary embodiment, in which the scraping surface 104 is defined by the wear elements 102a and 102b together. Another difference between the scraper 200 and the scraper 100 is that the scraping surface 204 of the scraping element 210 includes polycrystalline diamond (PCD).

[0247] As those skilled in the art will readily appreciate, diamond can be a single, continuous crystal or it can be composed of many smaller crystals (polycrystals). Large, shiny and transparent single-crystal diamond is commonly used as a gemstone. Polycrystalline diamond (PCD) is composed of many small grains and is easily visible to the naked eye through strong light absorption and scattering; it is not used as a gemstone but is used in industrial applications such as mining and cutting tools. Polycrystalline diamond is often described by the average size (or grain size) of the crystals that make it up. Grain sizes range from nanometers to hundreds of micrometers and are often referred to as "nanocrystalline" diamond and "microcrystalline" diamond, respectively.

[0248] For scraper 200, scraping element 210 also includes a wear-resistant material in which polycrystalline diamond (PCD) is at least partially embedded. In alternative embodiments, polycrystalline diamond (PCD) may be attached to the surface of the wear-resistant material of scraping element 210. For exemplary embodiments, the wear-resistant material is a sintered carbide including tungsten carbide and cobalt as a binder. The binder content can typically be 10-15wt%. Other wear-resistant materials are also conceivable. Such alternative materials include other ceramic materials, such as titanium carbide or vanadium carbide; metal-ceramic composites, such as sintered carbides, such as titanium carbide, tungsten carbide or vanadium carbide, where cobalt is used as a binder; or metal matrix composites including titanium carbide, tungsten carbide or vanadium carbide.

[0249] In one embodiment, polycrystalline diamond (PCD) is embedded in tungsten carbide, vanadium carbide, or titanium carbide.

[0250] One advantage of a scraping surface 204 comprising polycrystalline diamond (PCD) is that it can significantly extend the wear life of the scraper 200. Typically, such a scraping surface 204 would include a wear-resistant material such as ceramic or a composite material including tungsten carbide, titanium carbide, and vanadium carbide, but for a scraping surface 204 comprising polycrystalline diamond (PCD), the wear life can be extended by up to about 50 times compared to a composite material comprising, for example, tungsten carbide alone.

[0251] The scraping element may include a layer of polycrystalline diamond (PCD).The polycrystalline diamond (PCD) layer may have a thickness of 0.4 to 3.2 mm, or 1.0 to 2.0 mm, or 1.35 to 1.8 mm, or 1.4 to 1.6 mm, or about 1.5 mm.

[0252] The diamond grain size of the polycrystalline diamond (PCD) of the scratched surface may be 0.8 to 30 μm, as determined by image analysis using a scanning electron microscope (SEM).

[0253] The grain size of the diamond can be measured by various measurement techniques, such as a laser size analyzer or a scanning electron microscope (SEM). An example of a laser size analyzer is the Malvern particle size analyzer device based on laser diffraction. The value determined using the laser size analyzer may be the initial diamond grain size, which in some embodiments may be subsequently subjected to high pressure and high temperature sintering. When the diamond particles have been sintered and compacted to form the scratched surface polycrystalline diamond (PCD), image analysis by scanning electron microscopy is used to determine the final microstructure grain size distribution, i.e. the diamond grain size of the scratched surface polycrystalline diamond (PCD).

[0254] The scraper 200 also includes a scraper body 203, which is structured and arranged to support the scraper element 204 during use. The scraper body 203 can be made of a resilient material such as steel. However, other materials are also contemplated, such as hardened white cast iron and / or manganese steel.

[0255] Although not shown here, it is also conceivable to provide polycrystalline diamond (PCD) for other surfaces of the scraper element 210. For example, the side surface of the scraper element 210 can include polycrystalline diamond (PCD). Expressed in another way, the scraping surface 210 can extend to also surround the side surface of the scraper element 210.

[0256] The scraping element 210 and the scraper body can be attached to each other by brazing. However, other alternative attachments are also possible, such as welding, gluing, hook and loop fasteners, threading or bolting, or a combination thereof.

[0257] like Fig. 14B Best shown with Figure 3C Like the scraper 100 shown in , the scraping surface 204 is arranged to be inclined relative to the normal N of the inner surface of the flange 39, and the inclination is such that the distance L1 between the normal N of the inner surface 39 of the flange 36 and the scraping surface 204 decreases toward the flange 36. The advantage of inclining the scraping surface 204 relative to the normal of the inner surface 39 of the flange 36 and decreasing the distance L1 toward the flange 36 is that the material removed from the position in the corner formed by the outer surface 37 of the roller 3 and the inner surface 39 of the flange 36 will be pushed toward the center of the roller 3 by the inclined scraping surface 204, rather than being squeezed and compacted between the scraper element 210 and the inner surface 39 of the flange 36. For the exemplary embodiment, the scraping surface 204 is substantially planar. Therefore, for the exemplary embodiment, the varying distance L1 as described above can be further expressed as an angle α defined between the scraping surface 204 and the normal N. As Fig. 14B The angle α may be 1 to 15°, or 2 to 10°, or 3 to 8°, or 4 to 6°, or 5°.

[0258] The scraper 200 has an extension from the scraping element 210 toward the rear end 209 of the scraper 200. Fig. 14B As best shown, the scraper body 203 has a surface 206 facing the flange 36 and two surfaces 207, 208 facing away from the flange 36. When the scraper 200 is mounted at a predetermined position on the roll crusher 1, some of these surfaces 206, 207, 208 form an oblique angle with the inner surface 39 of the flange 36. In particular, the scraper 200 is constructed and arranged so that the distance L2 between the surface 206 facing the flange 36 and the inner surface of the flange 39 decreases towards the scraping element 210 over at least a portion of the extension. This shape can allow material removed from a location in the corner formed by the outer surface 37 of the roller 3 and the inner surface 39 of the flange 36 to tend to flow along the surface 206 of the scraper 200 facing the flange 36, and as the distance away from and downstream of the scraping surface 204 increases, the removed material will be allowed to be removed toward the center of the roller, rather than being squeezed and compacted between the scraper 200 and the inner surface 39 of the flange 36. For the exemplary embodiment, the surface 206 is substantially planar. Therefore, for the exemplary embodiment, the varying distance L2 as described above can be further expressed as an angle β defined between the surface 206 facing the flange 36 and the inner surface 39 of the flange 36. This is also Fig. 14B The angle β may be 5 to 25°, or 5 to 20°, or 5 to 15°, or 8 to 12°, or 10°.

[0259] In addition, the structure and arrangement of the scraper 200 further causes the distance L3 between the surfaces 207, 208 facing away from the flange 36 and the inner surface 39 of the flange 36 to decrease toward the scraping element 210 over at least a portion of the extension. For the scraper 200, the surface 207 will have a varying distance starting from the minimum distance S3 to the inner surface 39 of the flange 36 and extending away from the inner surface 39 of the flange 36, while the surface 208 is substantially parallel to the inner surface 39 of the flange. The surfaces 207, 208 facing away from the flange 36 are opposite to the surface 206 facing the flange 36. Likewise, the scraper 200 provides a surface 207 that will push the removed material toward the center of the roller 3, which is beneficial. For the exemplary embodiment, the surfaces 207, 208 facing away from the flange 36 include a surface 207 and a surface 208, and both surfaces 207 and 208 are substantially planar. As shown in FIG. Fig. 14B As can be clearly seen, surface 208 is substantially parallel to inner surface 39 of flange 36. Thus, for the exemplary embodiment, the varying distance L3 as described above can be further expressed by an angle γ defined between surface 207 facing away from flange 36 and inner surface 39 of flange 36. This is also illustrated in FIG. Fig. 14BAngle γ may be 5 to 25°, or 5 to 20°, or 5 to 15°, or 8 to 12°, or 10°. Angle β and angle γ may be equal to each other in some embodiments.

[0260] A person skilled in the art will appreciate that not only the shape of the scraper (i.e. the scraper body 203 and the scraper elements 210) must comply with these geometrical restrictions, but also the orientation in which the scraper 200 is mounted to the roll crusher 1. In other words, the scraper 200 is constructed and arranged relative to the roll crusher 1 to achieve the described technical effect.

[0261] Scraper 200, similar to Figure 6 As shown, it is attached to the wedge-shaped element 520 described above. The through hole 527 is used to attach the wedge-shaped element 520 to the attachment surface by a fastener, such as Figure 6 The attachment surface 516 is shown. The through hole 528 is used to connect the chain 526 to an adjacent structure (such as Figure 6 The square beam 512 shown is connected.

[0262] Fig.16 The scraper 200 and the scraper 200' are shown when mounted on a roll crusher. The scraper 200' differs from the scraper 200 only in that it is a mirror image, in that it is disposed on the flange 36 opposite to the flange 36 on which the scraper 200 is disposed. Specifically, Fig.16 A scraper assembly 7000' is shown according to another example embodiment. The scraper assembly 7000' is similar to the scraper assembly 7000 described previously, but differs in that the scraper 100 is replaced by a scraper 200, 200', and there is only one scraper 200, 200' at each flange 36. In other words, the scraper assembly 7000' includes two scrapers 200, 200', each of which is arranged along a corresponding end of the roller 3 having a double flange 36. Within the scope of protection of the claims, each scraper 200, 200' can be installed according to any of the aforementioned combinations or any combination not described. The scrapers 200, 200' are each mounted on a support structure 710', which is in turn mounted on the frame of the roller crusher. As will be readily understood by those skilled in the art, the scraper assembly 7000' is constructed and arranged to be located at approximately 6 to 9 o'clock of the roller 4 when the roller 4 is viewed from the side showing clockwise rotation.

[0263] FIG. 15A to FIG. 15CA scraper 300 according to a third exemplary embodiment of the present disclosure is shown. The scraper 300 can be used to replace the scraper 100 or the scraper 200 already described, to replace the scraper in any one of Figures 4 to 14. The scraper 300 differs from the scraper 200 only in that the scraping element 310 includes a front portion 310a and a rear portion 310b attached to each other. The front portion 310a has a scraping surface 304. Although the front portion 310a of the scraper 300 and the scraping element 210 of the scraper 200 can be implemented differently from each other, such as by the selection of wear-resistant materials, thickness, etc., it is also conceivable that the front portion 310a of the scraper 300 and the scraping element 210 of the scraper 200 are the same as each other. The rear portion 310b has a surface 305 facing the flange 36 and a surface 301 facing away from the flange 36. The surface 305 and the surface 301 are substantially parallel to each other. In addition, the surface 305 and the surface 301 can be substantially parallel to the inner surface 39 of the flange 36. It is conceivable that the surface 305 and the surface 301 include polycrystalline diamond (PCD). It is also conceivable that the other or all side surfaces of the rear portion 310b include polycrystalline diamond (PCD). The scraper 300 also includes a scraper body 303, which is constructed and arranged to support the scraper element 310 during use. The scraper body 303 can be made of the same kind of material as the scraper body 203 listed above. The difference between the scraper body 303 and the scraper body 203 is that the scraper body 303 has a shorter extension from the scraping element 310 to the rear end 309 to adapt to the larger size of the scraping element 310. The scraper element 303 has a surface 307, 308 away from the flange 36 and a surface 306 facing the flange 36. The scraper 300, in particular the shape and arrangement of the scraper body 303 relative to the roller 3 can be the same as the shape and arrangement of the scraper 200 and its scraper body 203 described in detail above. Specifically, the distances L1, L2, and L3 that may be defined for scraping surface 304 and surfaces 307, 308, and 306 may vary in the same general manner as scraper 200. The angular intervals for angles α, β, and γ may also follow the ranges provided for scraper 200 above.

[0264] The front portion 310a and the rear portion 310b may be attached to each other by brazing, but may also be integrally manufactured with the polycrystalline diamond provided at the scraping surface 304 of the scraping element 310. The rear portion 310b and the scraper body 303 may also be attached to each other by brazing. However, other alternative attachments are also possible, such as welding, gluing, hook and loop fasteners, threaded or bolted connections, or combinations thereof.

[0265] Those skilled in the art will appreciate that the present disclosure is by no means limited to the preferred embodiments described above. On the contrary, within the scope of the appended claims, many modifications and variations are possible. In addition, by studying the drawings, the present disclosure, and the appended claims, the technical staff practicing the claims can understand and implement the changes to the disclosed embodiments.

[0266] List of Examples

[0267] Embodiment 1. A roller crusher having two substantially parallel rollers arranged to rotate toward each other in opposite directions and separated by a gap, each roller having two ends, the roller crusher comprising:

[0268] a flange attached to at least one end of one of the rollers,

[0269] The flange extends in the radial direction of the roller,

[0270] The flange has a height (H) exceeding the outer surface of the roller,

[0271] wherein the roller crusher further comprises at least one scraper arranged at the end of the roller having the flange for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller, and

[0272] Each of the at least one scraper blades includes a scraping element having a scraping surface, the scraping surface including polycrystalline diamond (PCD).

[0273] Embodiment 2. The roll crusher according to embodiment 1, wherein the scraping element further comprises a wear-resistant material, and the polycrystalline diamond (PCD) is at least partially embedded in the wear-resistant material.

[0274] Embodiment 3. The roller crusher according to embodiment 2, wherein the wear-resistant material is one of the following: a ceramic material, a metal-ceramic composite material, and a metal-matrix composite material.

[0275] Embodiment 4. A roller crusher according to any one of embodiments 1 to 3, wherein the scraping surface of at least one scraper is arranged to be inclined relative to the normal line of the inner surface of the flange, and is inclined so that the distance between the normal line of the inner surface of the flange and the scraping surface decreases toward the flange.

[0276] Embodiment 5. A roller crusher according to any one of embodiments 1 to 4, wherein at least one scraper has a surface facing the flange, which has an extension from the scraping element toward the rear end of the at least one scraper, wherein at least one scraper is constructed and arranged so that the distance between the surface facing the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension.

[0277] Embodiment 6. A roller crusher according to any one of embodiments 1 to 5, wherein at least one scraper has a surface facing away from the flange, which has an extension from the scraping element toward the rear end of the at least one scraper, wherein at least one scraper is constructed and arranged so that the distance between the surface facing away from the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension.

[0278] Embodiment 7. A roll crusher according to any one of embodiments 1 to 6, wherein the scraping element comprises a front part and a rear part attached to each other, and wherein the front part has a scraping surface.

[0279] Embodiment 8. A roller crusher according to embodiment 7, wherein the rear portion has a surface facing the flange and a surface facing away from the flange, the surfaces being substantially parallel to an inner surface of the flange.

[0280] Embodiment 9. The roll crusher according to any one of embodiments 1 to 8, wherein at least one scraper is arranged at a lower portion of the roll crusher.

[0281] Embodiment 10. A roller crusher according to any one of embodiments 1 to 9, wherein at least one scraper is arranged so that a scraping surface of the at least one scraper is at least partially facing downward to allow removed material to leave the roller and the scraping surface by gravity.

[0282] Embodiment 11. A roller crusher according to any one of embodiments 1 to 10, wherein at least one scraper has a fastening position, which is located at a certain distance from the outer surface of the roller, and wherein at least one scraper is arranged so that the scraping surface of at least one scraper is located at a radial axis, or is continuous with the radial axis, which extends from the rotation axis of the roller and passes through the fastening position.

[0283] Embodiment 12. A roller crusher according to any one of embodiments 1 to 11, wherein the roller crusher further comprises at least one holding clamp for at least one scraper, the at least one holding clamp being connected to the frame of the roller crusher at a fastening position of the at least one scraper.

[0284] Embodiment 13. A roller crusher according to embodiment 12, wherein at least one retaining clamp includes at least one bracket and at least one wedge element, which is constructed and arranged to attach at least one scraper to at least one bracket so that the angular position of at least one scraper is offset in the rotation plane of the roller relative to the angular position of at least one bracket.

[0285] Embodiment 14. The roller crusher according to any one of embodiments 1 to 13, wherein the roller crusher further comprises a flexible retaining device arranged to interconnect at least one scraper with a frame of the roller crusher.

[0286] Embodiment 15. A roller crusher according to any one of embodiments 1 to 14, wherein at least one scraper is at least two scrapers arranged continuously to each other at the end of the roller having a flange, for at least partially removing material accumulated on the outer surface of the flange and / or the end of the roller.

[0287] Embodiment 16. A roller crusher according to embodiment 15, wherein at least two consecutive scrapers are arranged at an equal distance from the flange and / or from the outer surface at the end of the roller.

[0288] Embodiment 17. A roller crusher according to embodiment 15, wherein at least two consecutive scrapers are arranged at different distances from the flange and / or from the outer surface at the end of the roller.

[0289] Embodiment 18. A roller crusher according to embodiment 17, wherein at least two consecutive scrapers are arranged with a decreasing distance from the flange and / or from the outer surface of the roller as seen from the leading scraper to the consecutive scraper.

[0290] Embodiment 19. A roller crusher according to embodiment 17, wherein the at least two continuous scrapers include at least two subsets of at least two continuous scrapers, wherein at least two continuous scrapers in each subset are arranged at the same distance from the flange and / or the roller surface, and wherein at least two subsets of the continuous scrapers are arranged at different distances from the outer surface at the end of the flange and / or the roller.

[0291] Embodiment 20. A roller crusher according to embodiment 19, wherein at least two subsets of consecutive scrapers are arranged at decreasing distances from the outer surface of the flange and / or the end of the roller as seen from a leading subset to a consecutive subset.

[0292] Embodiment 21. A roller crusher according to any one of embodiments 1 to 20, wherein the roller crusher includes two flanges attached to opposite ends of one of the rollers, and wherein at least one scraper includes a first subset of at least one scraper and a second subset of at least one scraper, the first subset and the second subset are each arranged on a corresponding end region of the roller having the two flanges.

[0293] Embodiment 22. A roller crusher according to any one of embodiments 1 to 21, wherein the roller crusher also includes a remote material removal device, which is configured to output a material removal beam toward a target area, wherein, at the end of a roller having a flange, the remote material removal device and at least one scraper are arranged continuously with each other for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller.

[0294] Embodiment 23. A roll crusher according to Embodiment 22, wherein the target area of ​​the remote material removal device is located in front of at least one scraper.

Claims

1. A roller crusher, characterized in that: Having a frame and two substantially parallel rollers arranged to rotate in opposite directions towards each other and separated by a gap, each roller being arranged in a respective bearing seat arranged in the frame, each roller having two ends, the roller crusher comprising: a flange attached to at least one end of one of the rollers, The flange extends in the radial direction of the roller, The flange has a height (H) exceeding the outer surface of the roller, wherein the roller crusher further comprises at least one scraper arranged at the end of the roller having the flange for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller, and Each of the at least one scraper blades comprises a scraping element having a scraping surface, the scraping surface comprising polycrystalline diamond.

2. The roller crusher according to claim 1, characterized in that The scraping element further comprises a wear-resistant material, and the polycrystalline diamond is at least partially embedded in the wear-resistant material.

3. The roller crusher according to claim 2, characterized in that The wear-resistant material is one of the following: a ceramic material, a metal-ceramic composite material and a metal-matrix composite material.

4. The roller crusher according to any one of claims 1 to 3, characterized in that The scraping surface of the at least one scraper is arranged to be inclined relative to a normal to an inner surface of the flange and is inclined such that a distance between the normal to the inner surface of the flange and the scraping surface decreases towards the flange.

5. The roller crusher according to any one of claims 1 to 3, characterized in that The at least one scraper has a surface facing the flange, the surface having an extension from the scraping element toward the rear end of the at least one scraper, wherein the at least one scraper is constructed and arranged so that the distance between the surface facing the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension.

6. The roller crusher according to any one of claims 1 to 3, characterized in that The at least one scraper has a surface facing away from the flange, the surface having an extension from the scraping element toward the rear end of the at least one scraper, wherein the at least one scraper is constructed and arranged so that the distance between the surface facing away from the flange and the inner surface of the flange decreases toward the scraping element over at least a portion of the extension.

7. The roller crusher according to any one of claims 1 to 3, characterized in that The scraping element comprises a front part and a rear part attached to each other, and wherein the front part has the scraping surface.

8. The roller crusher according to claim 7, characterized in that The rear portion has a surface facing the flange and a surface facing away from the flange, and the surfaces are substantially parallel to the inner surface of the flange.

9. The roller crusher according to any one of claims 1 to 3, characterized in that The at least one scraper is arranged at a lower part of the roll crusher.

10. The roller crusher according to any one of claims 1 to 3, characterized in that The at least one scraper is arranged such that a scraping surface of the at least one scraper is at least partially facing downwardly to allow removed material to escape from the roller and the scraping surface by gravity.

11. The roller crusher according to any one of claims 1 to 3, characterized in that The at least one scraper has a fastening position, which is located at a certain distance from the outer surface of the roller, wherein the at least one scraper is arranged so that the scraping surface of the at least one scraper is located at a radial axis or is continuous with the radial axis, which extends from the rotation axis of the roller and passes through the fastening position.

12. The roller crusher according to any one of claims 1 to 3, characterized in that The roll crusher further comprises at least one holding clamp for the at least one scraper, the at least one holding clamp being connected to the frame of the roll crusher at a fastening location of the at least one scraper.

13. The roller crusher according to claim 12, characterized in that The at least one retaining fixture comprises at least one bracket and at least one wedge element, wherein the wedge element is constructed and arranged to attach the at least one scraper to the at least one bracket so that the angular position of the at least one scraper is offset in the rotation plane of the roller relative to the angular position of the at least one bracket.

14. The roller crusher according to any one of claims 1 to 3, characterized in that The roller crusher further comprises flexible holding means arranged to interconnect the at least one scraper and a frame of the roller crusher.

15. The roller crusher according to any one of claims 1 to 3, characterized in that The at least one scraper is at least two scrapers arranged successively to each other at the end of the roller having the flange for at least partially removing material accumulated on the outer surface at the flange and / or the end of the roller.

16. The roller crusher according to claim 15, characterized in that The at least two scrapers in succession are arranged at equal distances from the flange and / or from the outer surface at the end of the roller.

17. The roller crusher according to claim 15, characterized in that The at least two scrapers in succession are arranged at different distances from the flange and / or from the outer surface at the end of the roller.

18. The roller crusher according to claim 17, characterized in that The at least two scrapers in succession are arranged in such a way that the distance from the flange and / or from the outer surface of the roller decreases, seen from the front scraper to one or more successive scrapers.

19. The roller crusher according to claim 17, characterized in that The at least two continuous scrapers include at least two subsets of at least two continuous scrapers, wherein the at least two continuous scrapers in each subset are arranged at the same distance from the flange and / or the roller surface, and wherein the at least two subsets of continuous scrapers are arranged at different distances from the outer surface at the end of the flange and / or the roller.

20. The roller crusher according to claim 19, characterized in that The at least two subsets of consecutive scrapers are arranged at decreasing distances from the flange and / or the outer surface at the end of the roller, seen from a leading subset to one or more consecutive subsets.

21. A roller crusher according to any one of claims 1 to 3, characterised in that The roller crusher comprises two flanges attached to opposite ends of one of the rollers, and wherein the at least one scraper comprises a first subset of at least one scraper and a second subset of at least one scraper, the first subset and the second subset are each disposed on a respective end region of the roller having the two flanges.

22. The roller crusher according to any one of claims 1 to 3, characterized in that The roller crusher also includes a remote material removal device, which is enabled to output a material removal beam towards a target area, wherein, at the end of the roller having a flange, the remote material removal device and the at least one scraper are arranged continuously with each other for at least partially removing material accumulated on the flange and / or on the outer surface at the end of the roller.

23. The roller crusher according to claim 22, characterized in that The target area of ​​the remote material removal device is located in front of the at least one scraper.

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