Arc-shaped and polygonal crusher tooth arrangement in rotor and roller crushers

Abstract

A crushing tooth arrangement on the circumference of the two rollers or rotors of a roller or rotor crusher with crushing teeth arranged in rows of teeth, wherein a row of teeth is described by a shortest and geometrically simplest connecting line of all teeth in an axial direction and a radial direction running along the circumference of the roller or rotor, wherein the connecting lines of the rows of teeth (1) of the rollers or rotors are arc-shaped, continuously differentiable lines and have opposite offset angle profiles (8) in the axial direction, which correspond to the profile of an axial mass flow (8) required to homogenize an inhomogeneous material distribution (6) along the length of the rollers or rotors, characterized in that the rows of teeth (1) have parabolic profiles (10) in the axial direction.

Description

[0001] The invention relates to the arcuate and polygonal arrangement of crushing teeth on the circumference of rotors or rollers of rotor or roller crushers (arc and polygonal formation). The tooth height h, relative to the rotor or roller outer diameter D, determines whether the crusher is a rotor crusher (shaft crusher, sizer) with toothed rotors (h / D ≥ 0.17) or a roller crusher with toothed rollers (h / D < 0.17).

[0002] Toothed rotors and rollers are used in rotor and roller crushers to improve feed rates and facilitate crushing through concentrated force application. The arrangement of the crushing teeth (tooth formation / crushing tooth arrangement) is of crucial importance. This affects the feed behavior, particularly the feed time for large material fragments, and thus the throughput behavior, especially the material distribution along the rotor or roller length (throughput behavior), and ultimately also the discharge behavior, particularly the proportion of oversize and deformed material in the crushed product. Furthermore, the crushing behavior, especially the required crushing work and the crushing force profile over time, and thus also the tooth wear along the rotor or roller length, can be influenced by the crushing tooth formation.

[0003] The tooth formation type is named after the shape of the connecting line between the tooth tips of a tooth row in the rotor or roller development. To uniquely characterize the formation type, it is first necessary to define which subset of teeth belongs to a tooth row, because otherwise any number of periodic patterns could be found. Fig. Figure 1 shows this using the example of an unwound roller with a spiral tooth arrangement according to EP 0 167 178 B1, where, in addition to the correct connecting line of the spiral formation (a), for example, lines of an arrow formation (b), multiple spiral formation (c) or alignment formation (d) could also be drawn.

[0004] First, it follows that the formation type depends only on the shape or inclination of axial connecting lines, and radial connecting lines as in Fig. 1(d) are not naming. The connecting line can, however, be partially ( Fig. 1a, b) or section by section also completely ( Fig. 1c) must be oriented radially, but must extend over the entire length of the roller. If it is further assumed that the shortest and geometrically simplest axial connection line is to be chosen, variants (b) and (c) are also eliminated, leaving only the desired variant (a). While straight lines or polygons always form the shortest connection line, they are not always the geometrically simplest (e.g., arrow formation with curved arrowheads according to EP 1 385 630 B1). By radially offsetting the in Fig. 1(a) defined tooth row by the value of the circumferential pitch t u This ultimately results in the complete tooth configuration of the roller.

[0005] Thus, a tooth row comprises all teeth in the axial direction that, in the unfolded view, describe the complete tooth configuration solely through radial offset and form the shortest and geometrically simplest connecting line (= formation line). Analogously to the tooth row, the tooth ring is defined in the radial direction, such that the number of teeth n is the product of the number of tooth rings n a and number of tooth rows n u is.

[0006] Based on this definition, the tooth arrangements belonging to the prior art, whether patented or otherwise, can be defined. Among the simplest formations is the alignment formation, in which the tooth row forms a straight line parallel to the axis of rotation of the roller or rotor body. Various offset formations are also well known, in which the tooth row forms a straight line or curved function that is not parallel to the axis.

[0007] EP 0 167 178 B1 discloses a spiral formation in which the tooth row forms a straight line inclined at an angle in the rotor or roller development. This formation is found on the two counter-rotating crushing rollers of a mineral crusher, between which the feed material is crushed. The spiral arrangement of one roller can run in the same or opposite direction to the opposing roller (cf. Fig. 2) If the material is fed in from the side parallel to the roller axes (axis-parallel feeding), the opposing spiral formation results in directed transport from the fed side of the roller to the opposite side. The same-direction spiral formation, on the other hand, causes undirected material transport above the rollers. With axis-perpendicular feeding, where the material is concentrated primarily in the center of the roller, the opposing spiral formation is only conditionally suitable, as it directs the material from the center in only one direction and thus only effectively utilizes one half of the roller. In both variants of this formation, each tooth of one roller is axially offset by t relative to its corresponding tooth on the opposing roller. a / 2 (cf. Fig. 1) so that they can mesh with each other as the rollers rotate. As another example, WO 2010 / 032037 A1 discloses a mineral crusher with rows of teeth having segmentally offset tooth groups, and in which a crushing gap is formed between a crushing roller and a side panel attached to a hinge.

[0008] If throughput and wear behavior are critical, particular attention must be paid to a uniform material distribution along the entire rotor or roller length. With axially parallel material feed from one rotor or roller end, this can best be achieved by a counter-rotating spiral formation (see figure). Fig. 2, A) are achieved because they activate axial transport to the opposite side, thus relieving the feed side. The axial transport processes above the rotors or rollers are effected by the offset tooth formation of the rotor or roller and the counter-rotor or counter-roller. As they move towards each other, these form an opening angle δ in the unfolding. In the case of the opposing spiral formation ( Fig. 2, A) this corresponds, for example, to twice the offset angle γ (δ = 2γ, cf. Fig. 1) However, rotor and roller crushers are usually fed perpendicular to the axis, resulting in varying material distribution along the rotors or rollers depending on the cross-sectional area of ​​the feed conveyor. A one-sided, axially parallel material feed is therefore not very advantageous.

[0009] EP 1 385 630 B1 describes an arrow formation, also classified as an offset formation, which is intended to solve the problem of one-sided material transport in a centric, perpendicular feed. The rollers of the multi-roll crusher described in this publication are equipped with rows of teeth that run arrow-shaped towards the center in the roller's development. Typically, the opposing arrow formations of both rollers are offset by half the axial pitch t. a / 2 offset from each other to allow the teeth to be combed. The following formations are revealed in the script (cf. Fig. 3): - Formations with equal / unequal arrow sides, - Formations with equally / unequally inclined arrow flanks, - Formations with straight / concave curved arrowheads, - Formations whose arrowhead points towards / away from the fracture line.

[0010] Material transport to the roller edges on both sides is only possible if the arrowheads point towards the crushing gap. Otherwise, the material moves towards the center of the rotor or roller.

[0011] From the prior art, tooth orders are also known in which the basic formations occur multiple times per row of teeth, resulting in a zigzag (multiple arrow formation) or obliquely offset (multiple spiral formation) shape.

[0012] It is also known to combine several basic formation types in each tooth row. For example, DE 20 2006 014 902 U1 describes a spiral arrow formation using the example of a single-roll crusher, in which the toothed roll interacts with an anvil, thus crushing the feed material. The arrangement principle is then transferred to a two-roll crusher. It is characterized by the fact that the teeth are initially grouped into tooth rings in the circumferential direction. Two adjacent tooth rings of a roll are offset from each other by a specific angle and form a tooth ring pair. Since, in addition to the tooth rings of a tooth ring pair, the tooth ring pairs of a roll are also axially offset, a spiral tooth arrangement with a superimposed arrow formation is created (cf. Fig. 4).

[0013] The invention is based on the objective of overcoming the disadvantages of the prior art and optimizing the intake, discharge, throughput, crushing and / or wear behavior of rotor and roller crushers through improved tooth arrangements.

[0014] This problem is solved by the crushing tooth arrangements of dependent claims 1, 5 and 9. Preferred embodiments of the invention are the subject of the respective dependent claims referring back.

[0015] According to the invention, the problem is solved by a crushing tooth arrangement on the circumference of the two rollers or rotors of a roller or rotor crusher, characterized in that the connecting lines of the tooth rows of the rollers or rotors are arc-shaped, continuously differentiable lines and have opposite offset angle profiles in the axial direction, which correspond to the course of an axial mass flow required to homogenize an inhomogeneous material distribution along the length of the rollers or rotors (arc formation).

[0016] The axial mass flow required for homogenization or equalization results from the differential mass balance between the excess or insufficient material added relative to a uniform cross-sectional area along the roller or rotor axis ( Fig. 5 A). Thus, for a real bulk cross-section, with a linear increase on both sides to a feed maximum in the center of the roller or rotor at L / 2 (L = roller length), the material to be fed or discharged axially has a double parabolic curve over the roller or rotor length with maxima at L / 4 and 3L / 4 and a minimum at L / 2 ( Fig. 5B). This axial mass flow, which achieves a uniform material distribution along the rotor or roller length, results from the integration of the linear progression of the difference in pile height between the idealized homogeneous and the real pile cross-section ( Fig. 5A, B).

[0017] To generate this axial mass flow, axial feed forces are necessary, which in rotating rollers or rotors are generated by the tooth tips of tooth arrangements with an offset angle γ > 0. The magnitude of this feed force depends on sin(γ), and since for small angles sin(γ) ≈ γ, there is a proportional relationship between the offset angle γ and the axial feed force or velocity. It follows that the offset angle profile required for homogenization corresponds to the profile of the axial mass flow required for homogenization. Fig. 5B). Only with an opposing arrangement of the tooth rows of the two rollers or rotors does a directed movement result from the respective axial feed forces generated.

[0018] Since the rises of a tooth row of the two rollers or rotors correspond exactly to the offset angle, their course can be determined by integrating the offset angle profile or the profile of axial mass flow ( Fig. 5B) determine directly. For the non-uniform fill cross-section with a linear increase on both sides to the feed maximum at L / 2 ( Fig. 5A) therefore arc-shaped tooth rows are necessary for homogenization ( Fig. 5C). For integration, the offset angle profile must be at least piecewise continuous (see below). Fig. 5, B). Consequently, the resulting formation line of the crushing teeth is continuously differentiable along the entire axial extent of the roller according to the invention. Advantageously, the crushing tooth arrangement according to the invention can thus homogenize any uneven material feed, provided it is known, along the rollers or rotors. Such homogenization along the rotors or rollers is advantageous because it reduces tooth wear in the center of the roller and thus increases the service life of the roller or rotor. In addition, it advantageously increases the material flow in the edges with low flow, thereby enabling a higher throughput.

[0019] According to the invention, each tooth of one roller is axially offset to its corresponding tooth on the counter roller in such a way that they can mesh with each other when the rollers rotate.

[0020] In a preferred embodiment of the arc formation according to the invention, the tooth rows are defined in the axial direction by polynomial functions second (cf. Fig. 7, A), third (cf. Fig. 7, B) or higher degree. Particularly preferably, the offset angles of the tooth rows decrease continuously in the axial direction up to a vertex S and exhibit a continuous profile over the entire axial extent of the roller or rotor. In contrast to known arrow formations, the vertices S of the arc-shaped connecting lines do not form any points of discontinuity (arrowhead), thus counteracting excessive stress on the central tooth ring. With the further preferred tooth rows, which have a parabolic profile in the axial direction, many real bulk material cross-sections can be advantageously homogenized easily, without knowledge of the exact cross-section, and thus conveniently along the roller or rotor axis.

[0021] Multiple configurations of the crushing tooth arrangement according to the invention are also preferred, wherein the tooth rows have in the axial direction repeating crushing tooth arrangements or offset angle profiles according to the invention. This allows several crushing centers to be established along the roller or rotor axis and also enables the homogenization of complex bulk material cross-sections. Such a crushing tooth arrangement particularly preferably has tooth rows that exhibit wave-like profiles in the axial direction. If several parabolic tooth configurations are arranged one after the other in the axial direction, the resulting multiple configuration is not continuously differentiable at the transitions of the repeating crushing tooth arrangements. Preferably, the multiple configuration has no further discontinuities apart from these transitions.

[0022] In a further preferred embodiment of the arc formation according to the invention, the tooth rows of both rollers or rotors have different offset angle profiles. Thus, the axial feed forces generated by the individual rollers can differ from one another. This advantageously allows the use of different rollers, whereby, for example, a more heavily loaded roller is replaced after a certain service life, while the other remains in the roller or rotor crusher.

[0023] In the inventive tooth arrangement for the teeth to mesh, it is also necessary that the rows of teeth on the two rollers are offset from each other in the axial direction. Therefore, arc formations according to the invention are particularly preferred in which the rows of teeth on both rollers or rotors are offset by a distance d in the axial direction. a > 0 (cf. Fig. 8) and reflection across a symmetry axis parallel to the axis of rotation can be brought into alignment. Advantageously, this allows for the realization of decentering or centering tooth formations with tooth rows whose vertices point towards or away from the fracture gap.

[0024] The crushing tooth arrangement according to the invention advantageously ensures that the teeth of the rotor or roller are used more evenly, which increases both the service life of the tooth assembly and the throughput of the rotor or roller crusher.

[0025] A further advantage is the versatile applicability of the arc formation according to the invention, which can be used for any ratio of tooth height h to tooth tip diameter D, i.e., both in rotor crushers with toothed rotors (h / D ≥ 0.17) and in roller crushers with toothed rollers (h / D < 0.17). Arc formations can also advantageously be made from any number of tooth rows n.u and toothed rings n a Arc formations can be formed with any spacing, not just equal spacing. Furthermore, arc formations can also be used for any rotor and roller pairings, e.g., one rotor and one roller, or two or more rotors and rollers with any tooth configuration relative to the interacting partner.

[0026] A further aspect of the invention is a crushing tooth arrangement on the circumference of the two rollers or rotors of a roller or rotor crusher, characterized in that the tooth rows of the rollers or rotors consist of axially aligned tooth subgroups with at least two teeth, which are offset in an arrow shape and arranged opposite to each other, such that a tooth subgroup forming the arrowhead has a greater distance to the entrance of the crusher gap in a roller or rotor cycle than the axially outer tooth subgroups. According to the invention, each tooth of one roller is axially offset from its corresponding tooth on the counter roller in such a way that they can mesh with each other as the rollers rotate (polygon formation).

[0027] The tooth rows are each formed from at least three tooth subgroups. The simplest arrow-shaped offset arrangement consists of the outermost tooth subgroups in the axial direction being positioned closer to the breaking gap in the roller or rotor configuration than the middle tooth subgroup. If the tooth row consists of more than three tooth subgroups, the outermost tooth subgroups in the axial direction are positioned radially closest to the breaking gap in the roller or rotor configuration. This radial distance then increases with each tooth subgroup, with the tooth subgroup forming the "arrowhead" having the greatest distance to the breaking gap in the roller or rotor configuration. If the tooth row has the same offset angle on both sides from this "arrowhead" towards the next tooth subgroups, corresponding tooth subgroups in the "arrow flanks" occupy the same radial positions.

[0028] A rotor or roller pairing with these crushing tooth arrangements with opposing tooth rows advantageously forms a polygonal crushing chamber in the unfolded state for penetrating and crushing large pieces of material (cf. Fig. 9, B). Due to the dependence of the feed behavior on the primary crushing space formed between the teeth above the rotors or rollers, this crushing tooth arrangement results in optimized feed behavior, particularly for large and hard pieces. Furthermore, a more uniform load can be achieved during crushing, as fewer teeth are engaged simultaneously. The polygonal formation according to the invention also advantageously reduces the risk of blockage during crushing operation due to the offset of the tooth subgroups.

[0029] In a preferred embodiment of the polygon formation, the row of teeth has different offset angles from the “arrowhead” towards the next tooth subgroups or between two corresponding tooth subgroups of the two “arrow flanks” (see figure). Fig. 10, A). Then, corresponding tooth subgroups in the two arrowheads of a tooth row each assume different radial positions. This advantageously prevents elongated oversize particles from slipping between the tooth rows uncrushed. Furthermore, this advantageously reduces the number of teeth simultaneously engaging the material to be crushed.

[0030] In a preferred embodiment of the crushing tooth arrangement, the tooth subgroups are tooth pairs or tooth triplets. It is also preferred that the number of crushing teeth varies between the individual tooth subgroups. This allows for the formation of complex polygonal crushing spaces, which can advantageously be adapted to a fracture pattern frequently occurring in a particular type of rock.

[0031] A polygonal formation is also preferred, in which the tooth rows have multiple tooth subgroups offset from each other in an arrow-like manner. This allows several fracture zones to be advantageously created along the roller or rotor length (cf. Fig. 11, A).

[0032] The polygon formations according to the invention are advantageously versatile, in particular for any ratio of tooth height h to tooth tip diameter D, i.e. both in rotor crushers with toothed rotors (h / D ≥ 0.17), as well as in roller crushers with toothed rollers (h / D < 0.17), for any number of tooth rows n u and toothed rings n a , which have any, in particular not only equal, distances from each other and for any rotor or roller interaction pairings consisting of one rotor and one roller or two or more rotors and rollers with any tooth formation relative to the interaction partner. Examples of implementation

[0033] The invention will be explained in more detail below with reference to several exemplary embodiments and illustrations, without being limited to these examples. The illustrations show: Fig. 1: Roll development of a roll with spiral (a), arrow (b), multiple spiral (c) or "alignment" (d) formation shown, as well as offset angle γ, circumferential pitch t u and axial division t a , Fig. 2: Roll development of a roll with spiral tooth arrangement according to EP 0 167 178 B1 with opposite (A) or similar orientation (B) of the tooth rows of roll and counter roll, Fig. 3: Roll development of a roll with arrow-shaped tooth arrangement according to EP 1 385 630 B1 with straight (A) and hollow conically curved (B) arrow flanks pointing towards the break gap, Fig. 4: Roll development of a roll with spiral tooth arrangement with superimposed arrow formation according to DE 20 2006 014 902 U1, Fig. 5: (A) the layer height applied across the roller or feed width of an idealized (5) and a real (6) layer cross-section at an angle of repose with a layer height maximum at L / 2; (B) the axial mass flow applied across the roller width for equalizing or homogenizing the idealized (7) and the real (8) layer cross-section; (C) roller development with the tooth row with alignment formation (9) required for homogenizing the idealized layer cross-section and the tooth row with arc formation (10) required for homogenizing the real layer cross-section, Fig. 6: an isometric 3-D view of a roller (A) and the associated roller development of an arc formation (10) (B), Fig. 7: Arc formation with formation lines of a polynomial function of second (A) and third (B) order, Fig. 8: Roller developments of a decentering (A) and a centering arc formation (B), Fig. 9(B): a roll development with polygon formation (11), Fig. 10: Roller developments of a polygon formation with unequal (A) and equal (B) offset angles between the tooth subgroups, Fig. 11: Roller development of a multi-polygon formation with two crushing chambers (A) and a polygon formation with different tooth subgroups (B).

[0034] A crushing roller with an arc formation 10 according to the invention is in Fig. 6 shown in a 3D view in cavalier perspective as well as in a roller development.

[0035] The in Fig. The seven exemplary arc formations include an arc formation with formation lines of a second-order (A) and third-order (B) polynomial function. Advantageously, the arc formations can be represented by polynomial functions of arbitrary order, since these are always continuously differentiable and exclude points of discontinuity, such as those that occur at the arrowhead in the arrow formation.

[0036] In Fig. Figure 8 shows arc formations with decentering (A) and centering (B) arc segments pointing towards and away from the crushing gap, respectively. Arcs pointing towards the crushing gap direct the material towards the rotor / roller edge (decentering), while arcs pointing towards the center (centering) are used for this purpose.

[0037] It is also possible to connect several arch formations in a wave-like sequence within a row of teeth in a multi-arch formation.

[0038] A crushing roller with a polygonal formation 11 according to the invention, with a polygonal crushing chamber 12, is in Fig. 9 is shown in an isometric 3D view as well as in a roller development.

[0039] The continued in Fig. The 10 exemplary polygon formations include those with the same ( Fig. 10B) and unequal ( Fig. 10A) Offset angle between the tooth subgroups and polygon formation with two 4 ( Fig. 10, Fig. 11) and three 13 ( Fig. 9, Fig. 11) Teeth per tooth subgroup. The number of teeth per tooth subgroup can also vary within a rotor or roller, or relative to the counter-rotor or counter-roller ( Fig. 11, B). Finally, it is also possible that several polygon formations are linked together within a row of teeth (multiple polygon formation) and thereby form several breaking spaces 12 ( Fig. 11, A). Reference symbol list 1 row of teeth 2 toothed ring 3 Ejection tooth (tip) 4 pairs of teeth 5 Idealized cross-sectional area 6 Actual cross-sectional area of ​​fill at an angle of repose 7 Axial mass flow rate required to homogenize the idealized bulk cross-section 8 Axial mass flow rate or offset angle profile required to homogenize the actual fill cross-section 9. Row of teeth required to homogenize the idealized pour cross-section (corresponds to alignment formation) 10. Number of teeth required to homogenize the actual pour cross-section (corresponds to arc formation) 11 Polygon formation 12 Polygonal primary refracturing chamber 13 tooth triplet

Claims

A crushing tooth arrangement on the circumference of the two rollers or rotors of a roller or rotor crusher with crushing teeth arranged in rows of teeth, wherein a row of teeth is described by a shortest and geometrically simplest connecting line of all teeth in an axial direction and a radial direction running along the circumference of the roller or rotor, wherein the connecting lines of the rows of teeth (1) of the rollers or rotors are arc-shaped, continuously differentiable lines and have opposite offset angle profiles (8) in the axial direction, which correspond to the profile of an axial mass flow (8) required to homogenize an inhomogeneous material distribution (6) along the length of the rollers or rotors, characterized in that the rows of teeth (1) have parabolic profiles (10) in the axial direction. Breaking tooth arrangement according to one of claims 1, characterized in that the offset angles of the tooth rows (1) decrease in the axial direction and in the direction of a vertex (S) and have a continuous course. A crusher tooth arrangement on the circumference of the two rollers or rotors of a roller or rotor crusher, with crusher teeth arranged in rows, wherein a row of teeth is described by a shortest and geometrically simplest connecting line of all teeth in an axial direction and a radial direction extending along the circumference of the roller or rotor, wherein the connecting lines of the rows of teeth (1) of the rollers or rotors are arc-shaped, continuously differentiable lines in axial sections and have opposite offset angle profiles (8) in the axial direction, which correspond to the course of an axial mass flow (8) required to homogenize an inhomogeneous material distribution (6) along the length of the rollers or rotors, wherein the rows of teeth (1) are formed from crusher tooth arrangements according to claim 1 that repeat themselves section by section in the axial direction. Breaker tooth arrangement according to one of the preceding claims, characterized in that the tooth rows of both rollers or rotors have different offset angle profiles (8). Breaker tooth arrangement according to one of the preceding claims, characterized in that the tooth rows (1) of both rollers or rotors can be brought into alignment by displacement in the axial direction by a distance da≥ 0 and reflection across an axis of symmetry parallel to the axis of rotation. A crusher tooth arrangement on the circumference of the two rollers or rotors of a roller or rotor crusher, with crusher teeth arranged in rows of teeth, wherein a row of teeth is described by a shortest and geometrically simplest connecting line of all teeth in an axial direction and a radial direction running along the circumference of the roller or rotor, characterized in that the rows of teeth (1) of the rollers or rotors each consist of at least three axially aligned tooth subgroups (13) with at least two crusher teeth (3) each, wherein the tooth subgroups are offset in an arrow shape and the rows of teeth are arranged opposite to each other, such that a tooth subgroup forming the arrowhead in a roller or rotor development has a greater distance to the entrance of the crushing gap than the tooth subgroups outer in the axial direction, wherein the tooth subgroups are arranged with different offset angles to each other. Breaking tooth arrangement according to claim 6, characterized in that the tooth subgroups are tooth pairs (4) or tooth triples (13). A crushing tooth arrangement according to one of claims 6 to 7, characterized in that the number of crushing teeth (3) varies between the tooth subgroups. Breaking tooth arrangement according to one of claims 6 to 8, characterized in that the tooth row (1) is formed from three tooth subgroups. Breaking tooth arrangement according to one of claims 6 to 8, characterized in that the tooth rows (1) have multiple tooth subgroups offset to each other in an arrow shape.

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