Material crusher equipped with grinding device, crushing plant and maintenance method

Abstract

The present invention relates to a material shredder 1, particularly for shredding recyclable cut materials, comprising a rotatably mounted rotor referred to as a cutting head 10 and a rotor housing referred to as a stator 20 substantially surrounding the cutting head 10, the rotor having a plurality of axially extending cutting blades 11 arranged on the rotor, the cutting blades being circumferentially spaced apart from one another and having radially outer cutting edges 12 forming a cutting circumference, the stator 20 and the cutting head 10 defining a cutting chamber 3 therebetween into which project the cutting blades 11 and at least one counter-blade 23 arranged on the inner circumference of the stator 20 and spaced radially apart from the cutting circumference so as to form a cutting gap 4, the stator 20 having at least one outlet 22 in which is arranged a sieve 24 defining the cutting chamber 3. According to the present invention, the material crusher 1 comprises a grinding device 30 with an abrasive holder 31 for holding an abrasive, the grinding device 30 being arranged outside the cutting circumference, and the abrasive and the sieve 24 being movable so that their respective radial spacing to the cutting circumference can be adjusted as desired. The present invention also relates to a crushing plant 100 with the material crusher 1 and a maintenance method.

Description

[Technical Field]

[0001] The present invention relates to a material crusher / shredder according to the features of the preamble of claim 1, which is specified for crushing / shredding waste, cutting material such as (fiber-containing) plastic material, in particular (recyclable) cutting material. The cutting or shredding material may contain interference material, for example silica-containing material and the like. Furthermore, when the cutting material is fed into the material crusher, it is not uniformly directed. [Background technology]

[0002] Crushers in general, and granulators in particular, have been known for a long time. Crushers of this type always have a cutting head, which is upright or horizontal, and are driven in rotation. Here, the term "cutting head" is used collectively for a rotor in the form of a drum, roller, etc., or for a rotor with one or more rotor blades. A number of shredding tools, in particular cutting blades, are generally arranged in the cutting head, and as the cutting head rotates, the cutting edges of the cutting blades form a cutting circumference. In the cutting region, and therefore at the periphery of the cutting circumference, the cutting blades may comprise a different material, such as tungsten carbide.

[0003] The cutting head is at least partially surrounded by a rotor housing, also referred to herein as a stator. The stator surrounds the rotatably mounted cutting head, and one or preferably several fixed counter blades are arranged on the inner circumference of the stator. The stator is generally designed as an at least partially cylindrical housing that defines a space surrounding the rotor, also referred to as a cutting chamber. The cut material is crushed in the cutting gap, which is formed as the radial distance between the cutting edge and the counter blade.

[0004] The cut material can be introduced into the cutting chamber through the inlet of the stator, and the crushed material can be discharged from the cutting chamber through the outlet of the stator (due to centrifugal force). Conveyor apparatuses that actively feed the cut material, i.e., conveyor apparatuses that partially push the cut material to the cutting circumference, are known. In a particularly simple embodiment, the inlet can be identical to the outlet. A conveyor and / or a collector can be provided adjacent to the outlet, respectively, to convey or collect the crushed material. A (perforated) screen arranged at the outlet and defining the cutting space in terms of size generally serves to determine the fine particle size of the crushed material discharged from the cutting chamber, whereby the cut material is crushed until it passes through the screen. Sieve sizes up to approximately 100 mm are particularly widely used. In connection with the counter blade, the screen allows the cut material to be partially cut multiple times, during which the cut material essentially does not receive a defined orientation in the cutting chamber.

[0005] The cutting blades and counter blades of a material shredder are subjected to various stresses during crushing, especially when the cut material contains silica-containing deposits. As wear progresses, the blade edge radius, i.e., the radius of the cutting edge realized by the two converging surfaces of the blade, which is crucial for shredding, increases, thereby increasing, for example, the required shredding energy. Furthermore, edge wear has the effect of widening the cutting gap. This leads to a decrease in cutting quality or cutting characteristics (cutting efficiency) because the cut material is crushed and / or torn, and the amount of unwanted dust with very small particle sizes in the cut material increases accordingly.

[0006] In order to nevertheless ensure sufficiently uniform cutting properties while using a moderate energy input and to ensure that the cut material can be transported reliably through the sieve, on the one hand the cutting edges and possibly also the counter blades must be regularly sharpened, i.e. the cutting edge radius must be reduced, and on the other hand the counter blade in particular must be readjusted so that the cutting gap can remain largely constant in relation to the appropriate cutting properties.

[0007] Patent Document 1 discloses a typical material crusher, proposing to arrange the cutting blades and counter-blade at an inclined angle relative to the rotation axis and at an equal angle to improve the cutting characteristics, so that the crushing of the cut material can be performed in a tangential cutting manner. Correspondingly, the spiral design of the cutting blade according to the present invention is said to be problematic in terms of regrind / sharpening the cutting blade. Currently, it is common practice to arrange the blades so that the cut material is crushed by tangential cutting, in order to reduce the stress on the blade or to extend its service life, respectively. It is also well known to provide the cutting edge with a particularly hard surface, etc., in order to extend its service life.

[0008] However, known material breakers commonly suffer from the problem that regrinding the cutting edges and / or counter blades is associated with economically inconvenient material breaker downtime, since the blades must eventually be removed for sharpening, which is very time-consuming, labor-intensive, and error-prone. Any downtime is particularly inconvenient in that material breakers typically represent a major piece of equipment within larger processing equipment, whereby the entire processing equipment is unproductive during maintenance of the material breaker. During blade removal and installation, it is further necessary to carefully clean the blade holder in which the blade is removably secured to prevent residue from remaining. Residue, particularly in the case of an uneven pressure fit when tightening the blade, can result in cracking or breaking of the secured blade or can locally exert increased stress on the cutting edge during the cutting process. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] DE865249C Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention is based on the problem of proposing a material crusher that can be operated in an economically advantageous manner with a longer service life, without compromising the cutting properties, i.e. the cutting quality, or without requiring a higher energy input to crush the cutting material, in particular recyclable waste, (fiber-containing) plastic material, etc. [Means for solving the problem]

[0011] This problem is solved by a material crusher according to the features of claim 1, a crushing plant according to the features of claim 15 and a method as claimed in claim 18.

[0012] The features of the device are described below. These design features may be implemented in conjunction with the present invention or are original in their own right independent of the present invention, and they may be implemented individually and independently of each other, or in any combination, including the implementation of all features described above, unless the combination is excluded due to expression or technical incompatibility.

[0013] In other words, the present invention proposes an apparatus for crushing cutting or crushing materials, specifically a material crusher. The present invention relates to a sharpening device that allows the cutting blades, particularly the cutting edges, of the cutting head to be sharpened while the cutting head is rotating, thereby economically avoiding long downtimes of the material crusher, since relatively high cutting characteristics, i.e., high cutting quality, can be ensured without removing the cutting blades. Furthermore, the risk of blade failure is reduced, since the clamping of the blade after sharpening is not always performed manually. Furthermore, as a result of the rotation during sharpening, an ideal geometric, substantially cylindrical cutting circumference can be achieved, so that the cutting edges of multiple cutting blades are each arranged circumferentially on the same circular orbit.

[0014] According to this proposal, the grinding device is arranged outside the cutting circumference, preferably radially outside the cutting circumference, with an abrasive receiver for holding the abrasive. The abrasive receiver may have an abrasive disc, an abrasive carrier, or the like connected to the abrasive, and the abrasive is particularly preferably detachably connected to the abrasive receiver, for example by adhesive bonding, adhesive, latching, or plug connection, so that the abrasive can be relatively easily replaced when worn. According to the present invention, the abrasive is movable in terms of its position, so that it can be selectively moved from a rest position in which it has no grinding effect, in which it is arranged outside the cutting circumference, to a grinding position in which it engages (interlocks) with the cutting edge of the cutting blade, and in the grinding position, a substantially tangential chamfer of the cutting blade is preferably generated toward the cutting circumference, thereby sharpening the cutting blade.

[0015] According to the present invention, the sieve, which occupies a substantial portion of the periphery of the stator, is likewise movable in its position, thereby allowing the cutting chamber, and thus the distance between the cutting circumference and the sieve, to be varied in size. If material removal increases during regrind of the cutting blades, the distance between the cutting circumference and the sieve is essentially enlarged. This is problematic insofar as the cutting blades function to push the cutting material through the sieve, if the cutting material is able to pass through the sieve. If the distance between the sieve and the cutting circumference increases, the cutting material is increasingly crushed, and the energy required to drive the cutting head increases. As a result of the sieve's mobility in its position, these disadvantages can surprisingly be avoided, and the stress acting on the cutting material can be reduced.

[0016] It is contemplated that one or more sieves may be arranged that are movable with respect to position. Furthermore, each sieve may be substantially integral or formed of multiple segments, whereby multiple sieve elements form one sieve. The sieve elements at the outlet may be aligned at an angle to each other. Alternatively, the sieve elements may be at least partially arcuate, so that multiple sieve elements achieve a larger arc.

[0017] In one design, the grinding device may have a guide, for example, in the form of a guide rail, a guide track, or the like. Particularly preferred is a linear guide, advantageously aligned substantially parallel to the longitudinal axis or rotation axis of the cutting head, in which the abrasive receiver is arranged so as to be movable along the cutting blade, specifically, so as to be movable with abrasive effect. For example, a grinding slide, grinding carriage, or the like, arranged on a running roller and movably connecting the abrasive receiver to the linear guide, may be arranged on the guide rail. The linear guide with the grinding slide functions to guide the abrasive back and forth in a reciprocating manner so as to produce a grinding effect along the longitudinal extension of the cutting blade. For example, scratches on the cutting edge of the cutting blade can be avoided due to the reciprocating motion. Furthermore, the cutting blade can be regrind very uniformly, producing a homogeneous cutting circumference along the cutting blade length. The area in which the abrasive engages the cutting blade is now referred to as the grinding area.

[0018] The abrasive slides, abrasive carriages, etc. are advantageously mechanically, hydraulically, pneumatically or electrically driven, for example by chain belt drive, tow rope drive, or the like.

[0019] In a very simple design, the abrasive can be held in a co-rotating manner on the abrasive receiver of the abrasive holder. In a preferred development, the abrasive holder can rotatably hold the abrasive, so that the abrasive is preferably rotatable around a rotation axis aligned substantially perpendicular to the rotation axis of the cutting head. The abrasive holder can be designed, for example, in the manner of a cup wheel. The abrasive can then be arranged in the cross-sectional area and rotatably held by the abrasive holder, so that the abrasive rotates in the direction of rotation of the cutting head and / or in the opposite direction during the reciprocating movement. The rotation speed of the abrasive is preferably slower than the rotation speed of the cutting head.

[0020] As an alternative to a cup wheel, the abrasive receiver may comprise a rotationally driven abrasive disc aligned substantially parallel to the axis of rotation of the cutting head, with abrasive disposed on at least its outer periphery, so that the abrasive is rotatable with or against the direction of rotation of the cutting head.

[0021] Each abrasive can rotate one or more complete revolutions around its own rotation axis, and the cutting edge is sharpened during this rotation of the abrasive. Similarly, it is also possible for the abrasive to rotate discontinuously around each arc so that the cutting edge is at least temporarily sharpened by the non-rotating abrasive. In this case, partial rotations of 3° to 270°, particularly preferably 5° to 30°, are advantageous. Any (partial) rotation of the abrasive is currently referred to as a rotation. Furthermore, it is also possible for the abrasive to rotate outside and / or inside the grinding area.

[0022] For the design of the movable position of the abrasive, the grinding device can be particularly advantageously provided with an abrasive actuator, particularly preferably in the linear guide, the abrasive receiver, and / or the abrasive holder. During this operation, the abrasive is selectively moved toward the cutting edge of the cutting blade or the radial distance of the abrasive from the cutting head is reduced. To increase the effectiveness of the abrasive, it is sufficient to rotate the abrasive so that at least a portion of the abrasive is brought closer to the cutting circumference or engaged with the cutting blade. Operation by the abrasive effect, i.e., when the abrasive engages with the cutting circumference in the grinding area, is currently called operational grinding or micro-grinding, while grinding without operation is called sparking.

[0023] The abrasive actuation can function to move the abrasive from a remote rest position to the abrasive position with an abrasive effect and / or further function to define the intensity of material removal during abrasion, and the actuation can preferably be intended to be stepless and continuous. For this purpose, the actuator can have, for example, one or more actuation screws, by which the radial spacing can be adjusted. Alternatively or additionally, a hydraulically or pneumatically driven cylinder or the like can be provided to actuate the abrasive or move it to a rest position.

[0024] A particularly inventive development can relate to a nozzle device on the grinding device. One or more preferred suction nozzles, suction ports, etc., now collectively referred to as suction nozzles, function to allow potential grinding debris to be directly removed from the grinding area. For this purpose, the suction nozzle is aligned with the cutting circumference with a suction effect, meaning that the suction effect of the suction nozzle extends substantially to the cutting circumference. The nozzle device is advantageously fluidly connected to a collection device in which the grinding debris is collected. In this way, the grinding debris can be prevented from contaminating the crushed material. Alternatively or additionally, an application nozzle can be installed that supplies, for example, a cooling fluid to the cutting circumference.

[0025] In a further design, the sieve can be rotatably supported, preferably parallel to the rotation axis of the cutting head, so that it can be rotated out of the outlet and exposed, allowing the cutting head or stator to be easily cleaned. On the other hand, the rotatable mounting allows the radial distance of the sieve from the cutting head, and thus the size of the cutting chamber, to be selectively adjusted in accordance with the sieve operation. This type of sieve device is advantageous for ensuring a very uniform distance between the cutting circumference and the sieve, so that an economically efficient energy input for driving the cutting head and only minimal effects on the material properties of the cut material, such as its elastic mechanical strength, can be realized in connection therewith.

[0026] A rotatably mounted sieve holder, acting on an adjusting device arranged outside the cutting chamber, may be provided for adjusting the distance and for fixing the sieve. Advantageously, the adjusting device may have an actuating pin that is held so as to be movable, preferably steplessly, essentially radially, and that is connected to the sieve holder and determines the proximity of the sieve to the cutting circumference. Alternatively or additionally, a pneumatically or hydraulically driven cylinder or the like may be provided, by means of which the rotation range of the sieve holder and of the sieve is adjustable.

[0027] Typically, the sieve may have a substantially rectangular shape curved to correspond to the diameter of the cutting head or the stator, in which case the sieve is rotatably held by its non-curved longitudinal side. At one end of the sieve, specifically at the opposite longitudinal side, in the edge region of the sieve, now referred to as the transition region, the sieve has a tapered material thickness with a decreasing cross section, and the stator and sieve are arranged so that they overlap each other at least in the transition region, with the sieve positioned radially inward there. The material thickness preferably decreases in the direction of rotation of the cutting head, so that the cut material does not unintentionally clog the cutting chamber, etc. The tapered overlap of the sieve and stator in the transition region facilitates sieve operation adapted to material removal caused by grinding.

[0028] A further development of the invention may include a control device that is connected to the grinding device, in particular to the abrasive actuator, in a signal-transmitting manner, and whose degree of actuation is preferably adjustable by a program. Alternatively or additionally, the control device may provide feedback control of the reciprocating motion that guides the abrasive along the cutting edge. Advantageously, an operating element is linked to the control device, allowing the operator to define, for example, an actuation or an actuation program. Alternatively or additionally, multiple sensors may be provided that detect the drive power of the cutting head, from which conclusions related to the wear of the cutting edge can be drawn and regrind of the cutting edge can be initiated, particularly automatically. For this purpose, the control device may preferably be designed to control the rotation of the cutting head.

[0029] In a particularly advantageous inventive design, the stator may have, outside the cutting circumference, one or more point-like and / or linear guide elements in the form of cams, guide ribs, lips, etc., which project radially into the cutting chamber. The guide elements may have the function of aligning the cut material, in particular film pieces, film strips, etc., during rotation of the cutting head. Thus, inter alia, the movement of the cut material on the sieve is reduced, the cutting properties and the discharge of the cut material from the cutting chamber are improved, so that the cutting edges of the cutting blades are subjected to less stress, and therefore the service life of the material shredder may be increased. For a particularly advantageous design, it may be provided that the guide elements are arranged on the sieve.

[0030] Once it leaves the cutting chamber, the cutting material can be an indicator of cutting edge wear. In the case of advanced wear, the cutting material typically exhibits a fibrous, torn coating surface. Furthermore, the dust content, i.e., the proportion of small cutting material particles, increases. Therefore, in one development, optical detection of the cutting material is provided, for example, by a camera detecting basic characteristics of the cutting material, such as its geometry and surface properties, which are preferably evaluated by software. If the detected actual value deviates excessively from the stored target value, an alarm signal can be emitted, drawing the user's attention to the need for regrind, for example. Alternatively, the alarm signal can be transmitted to a control device, which automatically initiates regrind.

[0031] Alternatively or additionally, the dust content in the outlet flow can be detected, for example, by resistance measurement, electrically, or by sieving methods, where the dust content is first separated and the weight of the dust content is then determined. As already indicated above, sensors can be installed to detect the power consumption of the drive for the cutting head, with increased power consumption of the drive generally indicating advanced wear of the cutting blade. In response to the established or derived cutting blade wear, a sharpening process can be carried out, initiated by the user or, particularly preferably, automatically by the control device.

[0032] Acoustic sensors, for example in the form of knock sensors, intended to detect the structure-borne noise vibrations created when the cutting edge passes the counter-blade, are particularly advantageous, and the size of the cutting gap generates a characteristic acoustic signal that is generally or perceptibly recognizable as a knock sound, respectively. In this way, conclusions regarding the wear of the cutting edge can be easily drawn and, if necessary, can be reacted to by manual or automatic regrind, as described above.

[0033] Alternatively or additionally, an acoustic sensor such as a knock sensor may serve, inter alia, to determine the distance between the abrasive and the cutting circumference, which is important, for example, when activating the abrasive: if activation is performed too quickly or if the abrasive engages too much with the grinding circumference, there is a risk of damaging the material breaker.

[0034] In one design, the material shredder may have a metal sensor that identifies metal components in the cutting material. Components of this type may be advantageously detected before being fed to the cutting chamber, preventing possible damage to, for example, cutting blades. To this end, the metal sensor may be connected to a control device that stops the feeding of cutting material to the cutting chamber and / or stops the cutting head upon detection of a metal component.

[0035] An essential factor for the cutting performance is, among other things, the size of the cutting gap between the cutting circumference and the counter blade. Advantageously, a blade holder can be provided that releasably fastens the counter blade to the stator, the blade holder being movable relative to the cutting head so that the counter blade can preferably continuously and steplessly approach the cutting circumference. Particularly preferably, regardless of the blade holder modification, the material shredder can currently have at least two counter blades. Preferably, the blade holder is electrically adjustable, for example, by a linear motor with an adjustment spindle, and a signal-transmitting drive is preferably connected to the control device for automatic adjustment of the cutting gap. Preferably, the counter blade is held in the blade holder in a clamping manner, for example, by a disk spring and / or hydraulic compression. This eliminates manual adjustment, leading to an extended service life. In particular, to enable manual readjustment of the counter blade, the blade holder can have multiple adjustment screws that determine the cutting gap.

[0036] In a further development of the invention, the blade holders can each have so-called blade seats for a number of counter-blades, the blade holders being preferably fastened to the blade seats by means of screws and being rotatably mounted so that the first blade seat with the counter-blade can be aligned in the operating position forming the cutting gap or in the rest position. In this way, the first counter-blade can be operated in the operating position, thereby significantly reducing the setup time, while the second counter-blade of the blade holder can be maintained, in particular sharpened.

[0037] In a particularly advantageous design, instead of or in addition to the nozzle device, a suction device can be provided connected to the outlet, in particular with a suction flow effect, so that the cut material in the cutting chamber can be sucked through the sieve to the outlet and eventually into the collection device. The suction supports the continuous removal of the cut material from the cutting chamber, so that the cut material can be crushed with high cutting quality and obstacles, for example, in the cutting chamber or on the sieve, can be avoided.

[0038] Furthermore, a suction device is advantageous for sucking in the shavings during the grinding process, for example, to avoid contamination of the cutting material when the cutting head is rotated and the cutting blade is sharpened, but the cutting material is not in the cutting chamber. In one development, a suction device can be installed that sucks in the shavings directly from the abrasive. For this purpose, for example, a suction nozzle can be provided that is connected to the grinding device with a suction flow effect and is installed on the grinding device. By arranging a filter or the like in the suction flow, the shavings can be separated from the suction flow, so that in principle, the cutting material can be crushed during grinding without contamination of the cutting material. This makes it possible to economically extend the service life of the material crusher.

[0039] A particularly preferred embodiment having one or more of the features described herein relates to a material crusher in the form of a granulator, which is used in particular to provide, after cutting, particularly fine material fragments, i.e. advantageously having a maximum edge length of substantially less than 100 mm, preferably substantially in the range from 20 to 100 mm, particularly preferably substantially less than 20 mm.

[0040] It is further proposed that the waste shredding plant is provided with a shredding device which is a material shredder, in particular a granulator, having the features according to the proposal and possibly according to the above-described developments, etc. Furthermore, the proposed shredding plant has a feeding device which transfers the cut material to the material shredder without substantial loss of the cut material, for example in the form of a funnel device, etc. Furthermore, the shredding plant can advantageously have a discharge device which conveys the material shredded by the material shredder, for example by means of a screw conveyor, slide, air current, etc.

[0041] In one design, the crushing plant may have at least one container for the shredded material, into which the crushed shredded material is conveyed as it passes through the sieve.

[0042] One development can provide a metering device arranged on the supply device to allow cutting material to be introduced into the cutting chamber as needed. First, this can prevent blockages in the cutting chamber, etc. Second, the supply of cutting material can be configured so that optimal utilization of the drive power of the cutting head can be achieved, for example, by a uniform load situation. Third, a substantially uniform drive power serves to detect wear of the cutting blades at an early stage and to react as needed, for example, by sharpening. Fourth, a kind of buffer storage can be created by the metering device, especially when spaced supply of cutting material is provided, for example, by individual trucks, wheel loaders, etc.

[0043] Advantageously, a conveying device can be provided which forms a conveying section which merges with the supply device, and by means of which the cutting material can be conveyed and supplied as continuously as possible, and in this connection the conveying device can also or in particular function as a metering device for the demand-dependent supply of cutting material.

[0044] The invention further relates to a maintenance method for a materials crusher, in particular for (re)establishing the operability of the material crusher, wherein an abrasive material is actuated towards the cutting edges of the cutting blades, the abrasive material is guided along the cutting blades, a sieve is actuated towards the cutting head, and the cutting head rotates at least during grinding. Preferably, the materials crusher has one or more of the above-described features.

[0045] In connection with actuation, as described above, abrasive material from an abrasive-free device is engaged with the cutting edge of the cutting blade, while the cutting blade is arranged to extend axially on a rotatably mounted rotor of the material breaker, referred to as the cutting head. As soon as the abrasive material engages the cutting edge, material can be removed from the cutting edge, reducing the cutting edge radius. On the other hand, material removal can be determined by actuation. With increasing actuation, i.e., the abrasive material moving radially closer to the cutting head, greater material removal is achieved, especially at the cutting edge.

[0046] According to this proposal, the abrasive material is guided along the cutting blades, preferably in a reciprocating motion, multiple times with a grinding effect, and it is crucial that the cutting head rotates during this process. Since the cutting edges can be machined, i.e., sharpened, while the cutting head is rotating, the service life of the material shredder can be economically extended. It is no longer necessary to disassemble the cutting blades before sharpening and then install the sharpened cutting blades in a costly manner. Furthermore, the rotation during sharpening achieves an ideal geometric shape, a substantially cylindrical shape of the cutting circumference, so that the cutting edges of the multiple cutting blades are each circumferentially arranged in the same circular path.

[0047] According to this proposal, the distance between the sieve and the cutting head or blade is reduced, and the sieve is located at the outlet of the stator. By reducing the distance, it is ensured that the cutting material is conveyed through the sieve when the cutting blade is sharpened, ensuring consistent cutting characteristics. The operation of the sieve can be carried out substantially simultaneously with the sharpening process.

[0048] In a further development of the method, radial movement of one or more counter blades may be provided, which are / are arranged on the inner circumference of a stator surrounding the cutting head, so that a substantially constant cutting gap between the counter blade and the cutting edge can be achieved. As material is removed from the cutting edge during sharpening, it may be necessary to adjust the radial spacing between the counter blade and the cutting blade or cutting head. A substantially constant cutting gap helps to extend the service life of the cutting blade, so that maintenance costs can be reduced and the service life can be extended.

[0049] The present invention is based on the concept of proposing an economically advantageous solution. Extensive automation significantly contributes to this. In particularly inventive developments, process steps can therefore be implemented in a feedback-controlled, i.e., coordinated, and particularly preferably, automatically, manner. The control device first evaluates signals that indicate increased cutting edge wear due to deviations of actual values ​​from target values. The power consumption of the cutting head and / or the cutting quality or dust content can be used as indicators of increased cutting edge wear. If increased wear is detected, sharpening of the cutting edge is initiated by the control device. For this purpose, the control device controls the activation of the abrasive material and its guidance along the cutting edge. As soon as the desired cutting quality is achieved again and / or the cutting edge has been sharpened based on known sharpening experience, sharpening is interrupted, where, for example, a certain number of strokes and / or a specific sharpening duration can be decisive. Because sharpening occurs during cutting head rotation and the rotational speed of the cutting head rotation is correspondingly feedback controlled, the cutting grade or cutting quality can be directly verified without costly installation and / or removal operations of the cutting blade.

[0050] The grinding chips are particularly advantageously sucked in during grinding. For this purpose, it is possible for the control device to provide feedback control of a suction device or the like. Furthermore, the control device can initiate the application of a coolant or the like to cool the cutting edge during grinding.

[0051] Furthermore, it is preferably provided that the control device feedback-controls the operation of the counter blade depending on the grinding intensity. For this purpose, the control device can process signals that can induce the material removal associated with grinding. On the other hand, it is also provided that the control device processes signals that can induce the spacing between the counter blade and the cutting circumference.

[0052] Alternatively or additionally, the feedback control of the maintenance steps can be according to predetermined (time) intervals, the individual process steps being particularly preferably feedback-controlled by a control device.

[0053] Advantageously, it may be provided that the counter blade is sharpened, in particular manually sharpened, before the actuation of the counter blade takes place.

[0054] It is contemplated that the above-described method steps are performed sequentially. Likewise, it is contemplated that some or all of the method steps are performed at least partially simultaneously. For example, a radial abrasive action is performed (step a) while the cutting edge is sharpened (step b). Furthermore, a radial sieve action (step c) is performed while the abrasive is being actuated and / or while the abrasive sharpens the cutting edge. A counter-blade action (step d) is initiated or completed after completion of steps a)-c) or during one of steps a), b), or c).

[0055] Exemplary embodiments of the invention are explained in more detail below in connection with the purely schematic drawings, in which individual features or combinations of features of the illustrated embodiments can also be realized independently of the remaining embodiments in the material crusher or in the crushing plant according to the proposal, respectively. [Brief explanation of the drawings]

[0056] [Figure 1a] 1 shows a cross-sectional view of a first exemplary embodiment of a crushing plant; [Figure 1b] FIG. 1 is a detailed view of a portion of a crushing plant. [Figure 1c] FIG. 1 is a detailed view of a portion of a crushing plant. [Figure 2] 2 is a perspective view of the polishing apparatus of the exemplary embodiment shown in FIG. 1, seen obliquely from above. [Figure 3] 3 is a detailed perspective view of the polishing apparatus of FIG. 2 as seen obliquely from below. [Figure 4] FIG. 2 is a perspective view of the exemplary embodiment of FIG. 1. [Figure 5] 1 shows another exemplary embodiment of an open crushing plant in a perspective view from diagonally above; [Figure 6] FIG. 6 shows a cross section of the example embodiment of FIG. [Figure 7] 6 is a cross-sectional view of the exemplary embodiment of FIG. 5 in a closed state. DETAILED DESCRIPTION OF THE INVENTION

[0057] FIG. 1 shows a first exemplary embodiment of a crushing plant 100 with a material crusher 1 and a feeding device 2 in a cross-sectional view. Several rotor blades 14 are arranged on a rotor shaft 15 to form a rotor, also referred to as a cutting head 10. The rotor is horizontally aligned, rotatably mounted, and driven, for example, by an electric motor. The cutting head 10 surrounds a rotor housing, designated a stator 20, which defines between them a cutting chamber 3 in which the cutting material is crushed. The stator 20 has an inlet 21 into which a funnel-shaped feeding device 2 opens (merges) to introduce the cutting material into the cutting chamber 3. The stator 20 further has an outlet 22 in which a (perforated) sieve 24 (hereinafter also referred to as sieve 24) is arranged. The sieve allows only sufficiently crushed cutting material to pass through, and thus, the material that can pass through the sieve. The shredded material leaving the sieve 24 enters a conveying device 5 which conveys the shredded material for further processing (not shown in the drawings). A selectively openable inspection flap 7 allows access to the cutting chamber 3.

[0058] The cutting head 10 in Figure 1a has a plurality of circumferentially spaced, axially extending cutting blades 11 with radially outer cutting edges 12 forming a cutting circumference. Arranged on the inner circumference of the stator 20 are a plurality of counter blades 23 which project into the cutting chamber 3 and form a cutting gap 4 with a radial clearance to the cutting blades 11 (Figure 1b). With increasing wear of the cutting blades 11 at the cutting edges 12 or with an increasing cutting edge radius, the cutting gap 4 increases (see also Figure 1c).

[0059] 1b shows in particular the sharpening device 30 in an enlarged detail. The sharpening device has a carriage-like abrasive receptacle 31, which is arranged outside the cutting circumference of the cutting blade 11. The abrasive receptacle 31 is guided along a linear guide 32 (see also FIGS. 2 and 4). A deflecting wedge 6 prevents, in particular, bulky cutting material from being inadvertently jammed or pushed into the crushing plant, so that the risk of breakdowns can be reduced. By engaging the sharpening pin 34 with the cutting edge 12, the cutting edge radius can be reduced.

[0060] The counter blade 23 is connected to a linear motor by means of an adjusting spindle 36 so as to be movable with respect to its position (FIG. 1c), so that the counter blade 23 can be operated largely automatically, in particular depending on the material removal by grinding. Furthermore, as can be seen in particular in FIG. 1c, there is a flap 37 which opens during the grinding of the cutting edge 12. In contrast, this flap 37 can be selectively closed if no grinding process is provided to close the opening in the stator 20 in order to prevent loss of cutting material.

[0061] 1a is arranged at the outlet 22, the sieve 24 occupies a substantial part of the circumference of the stator 20 surrounding the cutting head 10 and is fixed so as to be movable with respect to its position in a sieve holder 25. The sieve holder 25 is rotatable by means of a rotating base 26, the axis of rotation being adjusted and aligned with the axial direction of the cutting head 10 so that the radial spacing of the sieve 24 from the cutting head 10 or to the cutting circumference, respectively, can be adjusted.

[0062] In Fig. 1a an adjusting device 40 with an actuating pin 41 is arranged to act on the sieve holder 25, which causes a radial movement of the sieve 24 towards the cutting circumference so that the distance between the sieve 24 and the cutting blade 11 or the cutting circumference, respectively, is adjustable, in particular by means of a control dial. Despite the increased material removal associated with the grinding at the cutting edge 12, the distance between the cutting circumference and the sieve 24, which is related to the cutting characteristics and the drive energy requirements, can be kept largely constant and optimal, for example depending on the cutting material.

[0063] 2 shows a perspective view from diagonally above of the sharpening device 30 of the exemplary embodiment of FIG. 1. An abrasive receptacle 31 is held in a carriage-like manner along a linear guide 32, by means of which the sharpening pin 34 can be guided along the cutting edge 12. The abrasive receptacle includes, among other things, a nozzle device 35, with an application nozzle 35a arranged above the sharpening pin 34 and a suction nozzle 35b arranged below the sharpening pin 34. During sharpening, a cooling fluid is applied by the application nozzle 35a. The suction nozzle 35b has the function of making it possible to directly suck in the abrasive debris to prevent contamination of the cutting material.

[0064] FIG. 3 shows a detailed perspective view of the grinding device 30 of FIG. 2, viewed obliquely from below. The grinding pin 34 held in the grinding holder 33 is visible. A gear rim 38 around the grinding holder 33 interacts with a spring clip 39, which causes the grinding holder 33 to rotate the grinding pin 34 in only one direction and always in partial rotations, which correspond to a tooth length or a multiple thereof. Each partial rotation causes the grinding pin 34 to actuate, i.e., move closer to the cutting circumference or closer to the cutting edge 12 of the cutting blade 11, respectively. Here, actuation is preferably performed by rotating the cutting head 10 in the grinding region, which produces operational grinding.

[0065] A perspective view of a fragment of the exemplary embodiment of Figure 1 is shown in Figure 4. The linear guide 32 is fixed so as to be aligned parallel to the longitudinal extension of the cutting blade 11 and so as not to move. In a reciprocating manner indicated in the drawing by a double-headed arrow, the abrasive receiver 31 is moved back and forth during the sharpening process along the linear guide 32 and thereby along the cutting blade 11, while the sharpening pin 34 engages the cutting edge 12.

[0066] FIG. 5 shows another exemplary embodiment of a particularly compact solution for a crushing plant 100 in a perspective view from diagonally above. In this case, the crushing plant 100 is shown in an open state, i.e., in particular, with two sieves 24 pivoted upwards, each exposing an outlet 22, of which only one outlet 22 is visible here for illustration reasons (see also FIG. 6). In contrast to the first exemplary embodiment, the cutting head 10 is aligned vertically. The cutting material is fed from above via a feed device 2 parallel to the axis of rotation of the cutting head. A further difference is that instead of one, two sieves 24 are provided, each of which is pivotably held in a sieve holder 25. The linear guide 32 of the grinding device 30 is aligned parallel to the axis of rotation of the cutting head 10.

[0067] In Figure 6, the exemplary embodiment of Figure 5 is shown in a cross-section. The flap 37 is shown in an open state, which allows sharpening of the cutting edge 12 of the cutting blade 11 by means of the sharpening pin 34. The feed cone 8 of the cutting head 10 guides, among other things, the cutting material towards the rotating cutting blade 11. The cutting blade 11 interacts with the counter blade 23 to crush and shred the cutting material.

[0068] The exemplary embodiment of Figures 5 and 6 is shown in a cross-sectional view in a closed state in Figure 7. On the one hand, the flap 37 is shown in a closed state, so that the grinding device 30 cannot be operated in this configuration. On the other hand, the sieve 24 is shown with the outlet 22 closed. The cutting blade 11 of the cutting head 10, which together with the counter blade 23 defines the cutting gap 4, is also visible.

[0069] As an example, a maintenance method to be applied when the cutting blade 11 is particularly worn will be described below.

[0070] In doing so, the abrasive is engaged (meshed) with the cutting circumference formed by the cutting edge 12 of the cutting blade 11. The abrasive is actuated towards the cutting blade 11, i.e. the radial distance between the abrasive and the cutting edge 12 is reduced until the abrasive contacts the cutting edge 12. Depending on the further actuation of the abrasive after the initial contact between the abrasive and the cutting edge 12, the amount and degree of material removal of the cutting blade 11 is determined.

[0071] Starting either before or during feeding, the abrasive material is guided along the cutting edge 11 arranged axially on the cutting head 10. The cutting edge 12 is preferably ground multiple times in a reciprocating manner over the entire length of the cutting edge 11. It is important that the rotatably mounted cutting head 10 rotates during this process. The abrasive material is preferably held in the cross section of a cup wheel, which also rotates, while the abrasive material is guided back and forth along the cutting edge 12 in a reciprocating motion.

[0072] In the context of the exemplary maintenance method, the sieve 24 located at the outlet 22 of the stator 20 is further radially actuated, reducing the radial spacing of the sieve 24 from the cutting blades 11 .

[0073] After sharpening the cutting blade 11, or already during this time, the counter blade 23 arranged on the inner circumference of the stator 20 is activated so that the radial distance between the cutting blade 11 and the counter blade 23 is reduced, thereby setting a specific distance also called the cutting gap 4. If the counter blade 23 has become worn, it is also sharpened before activation. The operating steps of the maintenance method are feedback-controlled by a control device, so that an optimal and largely automatic maintenance can be performed. [Explanation of symbols]

[0074] 1 Material crusher 2 Feeding device 3 Cutting chamber 4 Cutting gap 5. Transporting Device 6 Deflection Wedge 7 Examination flap 8 Feeding Cone 10 cutting head 11 cutting blade 12 Cutting edge 14 rotor blades 15 rotor shaft 20 Stator 21 Entrance 22 Exit 23 Counter Blade 24 Sieve 25 Sieve holder 26 Rotating table 30 Polishing equipment 31 Abrasive Receptor 32 Linear guide 33 Abrasive holder 34 Polishing pin 35 Nozzle device 35a Applicable nozzle 35b Suction nozzle 36 Linear motor with adjustable spindle 37 Flap 38 Gear Rim 39 Spring Clip 40 Adjustment device 41 Operating pin 100 Crushing Plant

Claims

1. A material crusher (1) for crushing, in particular, recyclable cut materials, comprising: a rotatably mounted rotor called cutting head (10); a rotor housing, called a stator (20), that substantially surrounds the cutting head (10); The rotor is provided with a plurality of axially extending cutting blades (11) which are circumferentially spaced apart from one another and have radially outer cutting edges (12) which define a cutting circumference; The stator (20) and the cutting head (10) define a cutting chamber (3) disposed therebetween, into which the cutting blade (11) and at least one counter blade (23) disposed on the inner periphery of the stator (20) project; the counter blade (23) is positioned radially away from the cutting circumference to form a cutting gap (4); and A material crusher (1), wherein the stator (20) has at least one outlet (22) in which a sieve (24) defining the cutting chamber (3) is arranged, The material crusher (1) has an abrasive device (30) equipped with an abrasive receiver (31) for holding an abrasive; The grinding device (30) is positioned outside the cutting circumference; and 10. A material crusher (1) characterized in that the abrasive material and the sieve (24) are movable with respect to their positions such that their respective radial spacing from the cutting circumference is selectively adjustable.

2. 2. The material crusher (1) according to claim 1, characterized in that the grinding device (30) has a linear guide (32), and the abrasive receiver (31) is arranged in the linear guide (32) so as to be movable along the cutting blade (11).

3. 3. A material crusher (1) according to claim 1 or 2, characterized in that the abrasive receiver (31) comprises an abrasive holder (33) for rotatably holding the abrasive so that the abrasive is rotatable about an axis of rotation aligned substantially perpendicular to the axis of rotation of the cutting head (10).

4. 4. The material crusher (1) according to any one of claims 1 to 3, characterized in that the abrasive device (30) has an abrasive actuator specified for selectively adjusting the radial spacing of the abrasive material from the cutting head (10).

5. The polishing device (30) has a nozzle device (35), 5. A material crusher (1) according to any one of claims 1 to 4, characterized in that at least one suction nozzle (35b) is aligned with the cutting circumference with a suction effect and / or one application nozzle (35a) is aligned with the cutting circumference with an application effect.

6. The sieve (24) is held rotatably coaxially with the rotation axis of the cutting head (10), 6. A material crusher (1) according to any one of claims 1 to 5, characterized in that an adjusting device (40) acting on the sieve (24) so ​​that the radial distance of the sieve (24) from the cutting head (10) and therefore the size of the cutting chamber (3) is selectively adjustable is arranged outside the cutting chamber (3).

7. The sieve (24) in its edge region, called the transition region, has a material thickness that decreases in cross section at one end, and The stator (20) and the sieve (24) are arranged to overlap each other in the transition region; 7. Material crusher (1) according to any one of claims 1 to 6, characterized in that the sieves (24) are arranged radially inside.

8. Material crusher (1) according to any one of the preceding claims, characterized in that it comprises a control device connected to the grinding device (30) by signal transmission.

9. 9. A material crusher (1) according to any one of claims 1 to 8, characterized in that guide elements projecting radially inward into the cutting chamber (3) are arranged on the stator (20) outside the cutting circumference.

10. 10. A material shredder (1) according to any one of the preceding claims, characterized in that it comprises an optical detector of the cut material, which detects the cut material as it leaves the cutting chamber (3).

11. 11. A material crusher (1) according to any one of the preceding claims, characterized in that it comprises an acoustic sensor for detecting acoustic vibrations that occur when the cutting blades (11) pass over a counter blade (23), said acoustic vibrations serving to determine wear of the cutting blades (11).

12. Counter blades (23) are removably fixed to blade holders arranged on the stator (20); 12. A material crusher (1) according to any one of claims 1 to 11, characterized in that the blade holder is movable relative to the cutting head (10) so that the counter blade (23) has continuous access to the cutting circumference.

13. A blade holder arranged on the stator (20) has blade seats for a plurality of counter blades (23); and Material crusher (1) according to any one of the preceding claims, characterized in that the blade holder is rotatably mounted.

14. 14. A material crusher (1) according to any one of the preceding claims, characterized in that it comprises a suction device acting on the cutting chamber (3) via the outlet (22) for a suction effect.

15. A crushing plant (100), in particular for crushing recyclable cutting material, comprising a crushing device and a feeding device (2) specified for feeding the cutting material to said crushing device, Crushing plant (100), characterized in that the crushing device is a material crusher (1) according to any one of claims 1 to 14.

16. 16. The crushing plant (100) according to claim 15, characterized in that it comprises a metering device joining the feeding device (2), the metering device being specified for introducing a metered amount of chopped material into the cutting chamber (3).

17. 17. Crushing plant (100) according to claim 15 or 16, characterized in that it comprises a conveying device forming a conveying section, said conveying section joining said feeding device (2) and / or said metering device.

18. A maintenance method for a material crusher (1), comprising: a) radially applying an abrasive material to the cutting blades (11) arranged on the rotor of the rotatably mounted material crusher (1), the rotor being called the cutting head (10), so that said abrasive material is brought into abrasive engagement with the cutting edges (12) of said cutting blades (11); b) guiding the abrasive material along the cutting edge (11) with an abrasive effect, while the cutting head (10) rotates; c) radially moving the sieve (24) located at the outlet (22) of the stator (20) so that the radial distance of the sieve (24) from the cutting blades (11) is reduced; A maintenance method comprising method steps.

19. 20. A maintenance method according to claim 18, characterized in that d) radially actuating counter-blades (23) arranged in a rotor housing called a stator (20) surrounding the cutting head (10) so that the radial spacing between the cutting blades (11) and the counter-blades (23) is reduced.

20. 20. The maintenance method according to claim 18 or 19, wherein the method steps are feedback-controlled by a control device.

21. The maintenance method according to any one of claims 18 to 20, characterized in that the counter blade (23) is sharpened before operation.

Images