Sieve device and sieve shaft for a sieve device

Abstract

A sieving device (1) for separating solid mixtures as feed material according to particle size is shown and described, with a plurality of sieve shafts (4, 5) arranged downstream in a conveying direction of the feed material, wherein each sieve shaft (4, 5) rotates about its own axis of rotation and wherein a feed material is transported on the sieve shafts (4, 5) in the conveying direction according to the roller conveyor principle and is separated into a fine particle fraction and a coarse particle fraction. According to the invention, the sieve shafts (4, 5) are designed as conical sieve shafts with laterally projecting sieve blades (6) which form conical bodies of revolution when the sieve shafts (4, 5) are rotated, wherein the sieve shafts (4, 5) are arranged in the conveying direction of the feed material with alternating directions and wherein, when the sieve shafts (4, 5) are rotated, sieve gaps (9) are formed between the sieve blades (6) of adjacent sieve shafts (4, 5) for separating the feed material.

Description

[0001] The invention relates to a screening device for separating solid mixtures as feed material according to particle size, in particular for separating materials that are difficult to screen, moist and / or sticky and / or prone to wrapping, such as household and commercial waste, mixed construction waste, rubble, excavated soil, stockpile material from landfill remediation, alternative fuels, rolled goods and / or film and / or wire goods, biowaste, compost, waste wood, wood, green waste, with a separation deck comprising a plurality of screen shafts arranged side by side, wherein each screen shaft rotates about its own axis of rotation and wherein the feed material is transported in the conveying direction according to the roller conveyor principle and separated into a fine-grained fraction and a coarse-grained fraction.

[0002] Furthermore, the present invention relates to a sieve shaft for a sieve device of the aforementioned type.

[0003] The invention relates in particular to the technical field of classifying feed material, especially in the area of ​​waste separation. A clean or sufficiently precise separation of the feed material into different fractions makes it possible to directly utilize the various fractions of the feed material or to subject them to different post-treatment processes. For example, large or elongated pieces can be separated from smaller particles or components of the feed material.

[0004] In the context of the invention, the term "separation" includes, in particular, classification. Classification is understood to be a mechanical separation process for solid mixtures, whereby different geometric features, such as size and / or shape, are utilized for the separation process. This can result in a division into a fine-grained fraction and a coarse-grained fraction.

[0005] From EP 1 570 919 B1, a device for sorting essentially solid material is known, wherein in the known device spiral shafts rotate about their longitudinal axis as rotating elements. The spiral shafts are arranged parallel to each other in approximately one plane. Furthermore, the spiral shafts interlock and have the same direction of rotation. In the known device, the feed material is introduced laterally to the longitudinal axes of the spiral shafts. A coarse fraction of the feed material above the spiral shafts can be discharged through an open end of the spiral shafts, transverse to the longitudinal axis of the spiral shafts.

[0006] From DE 20 2022 105 600 U1, a star-shaped screening device with rotatable screening stars arranged on screening shafts, which interlock like a comb, is known. The feed material or material to be screened can be bulk materials, in particular mixtures containing soil, such as soil-covered crops and / or soil-covered stone material, compost, wood chips, or, for example, construction debris, household waste, or other municipal waste.

[0007] Problems during the separation of feed material with spiral shaft and star shaft screens can arise from long-fibered, thread-like, rope-like, net-like, or other coilable components contained in the feed material. Such materials can wrap around the screen shafts, requiring more energy for the rotary drive. In star shaft screens, the screen stars can also be damaged.

[0008] Spiral shaft sieving devices have the disadvantage that the feed material is often not moved sufficiently, as it is only transported flat over the shafts.

[0009] Star wave sieve devices are susceptible to embedded grain on both the left and right sides of the waves, which can damage the outer stars.

[0010] DE 195 00 022 A1 relates to a sieving device for classifying bulk materials that are difficult to sieve.

[0011] The object of the present invention is to provide a sieve of the type mentioned above that is improved compared to the prior art and is characterized by a very good separation result, particularly when separating feed material that tends to coil. In particular, it is an object of the present invention to provide a sieve that combines the advantages of spiral shaft sieves and star shaft sieves.

[0012] When handling material that tends to wrap, the screen shafts of the screen device should not be wrapped with long-fibered, thread-like, rope-like, net-like or other wrapable components, or only to a minimal extent.

[0013] Furthermore, when separating difficult-to-separate, moist or sticky material, blockages of the sieve gaps formed between the sieve shafts of the sieve device should be prevented to an improved extent by self-cleaning effects of the sieve shafts.

[0014] Manual loosening of feed material wound around sieve shafts should be avoided as much as possible during operation of the sieving device, so that uninterrupted operation of the sieving device is possible with low maintenance and operating costs as well as high efficiency, even when separating feed material that tends to wind.

[0015] Furthermore, improved removal of oversize material should be possible, with a high degree of loosening, separation, and mixing of the feed material occurring during transport on the screen shafts. In this context, it should be possible, in particular, to spread the feed material as far apart as possible during transport on the screen shafts, so that an approximately single-grain material layer is formed.

[0016] The aforementioned problems are solved by a sieving device with the features of claim 1 and by a sieve shaft for a sieving device with the features of claim 10. Advantageous embodiments of the invention are the subject of the dependent claims.

[0017] The screening device according to the invention comprises screen shafts with screen blades or profiles extending radially and longitudinally along the screen shafts. The invention proposes a screening device for separating solid mixtures as feed material according to particle size, in which the screen shafts are designed as conical screen shafts with laterally projecting screen blades. During rotation, the screen shafts form conical bodies of revolution, with the screen shafts arranged in alternating directions in the transport or conveying direction of the feed material. During rotation of the screen shafts, gaps are formed between the screen blades of adjacent screen shafts to separate the feed material.

[0018] Each screen shaft of the sieve device according to the invention has a plurality of flat screen blades extending along the axis of rotation of the respective screen shaft and preferably being planar. The longitudinal edges of the screen blades can form the lateral edges of a right, regular pyramid. The radially outer corners of the screen blades lie on a circle with a center point that lies on the axis of rotation of the screen shaft. The screen blades thus form a regular pyramid.

[0019] When the sieve shafts rotate, the laterally projecting sieve blades form cone- or conical bodies of revolution, defining the cone apex, a cone base and a cone shell or the generatrix of the body of revolution.

[0020] When the screen shaft rotates, the longitudinal edges of the screen blades form the lateral surface of a cone-shaped body of revolution extending from a cone base to a cone apex. The apex may be flattened, so that the body of revolution formed when the screen shaft rotates has the shape of a truncated cone. The cone base is located at one end of the screen shaft, with the screen blades having their maximum radial extent or maximum height at the base. The radial extent of the screen blades can then decrease towards the cone apex at the other end of the shaft, with the blades at the apex having their smallest radial extent. The longitudinal edges of the screen blades then form the generatrix of the cone-shaped body of revolution, connecting the base and the apex.The shape of the conical rotating bodies, which slopes downwards towards the cone tip, largely prevents the wrapping of the sieve shafts and moves the feed material inwards or towards the cone tip.

[0021] The longitudinal edges of the sieve blades preferably have a straight profile extending from the cone base of the rotating body formed by the rotation of the sieve shafts to the cone apex. An embodiment in which the longitudinal edges have a non-straight profile is not excluded.

[0022] The term “direction of a sieve shaft” within the meaning of the invention refers in particular to the orientation of the sieve shaft from the cone base of the body of revolution formed when the sieve shaft is rotated in the direction of the cone apex of the body of revolution.

[0023] The term "conical body of revolution" also includes bodies of revolution formed during the rotation of the screen shaft that are flattened at the cone apex, so that the body of revolution resembles a truncated cone. The truncated cone shape can positively influence the functioning of the screen shafts and the entire screening device. For example, a flattened cone apex can help to transport and separate the feed material more efficiently, as it is less likely that the material will become stuck at the tip of the conical shaft.

[0024] The sieve device according to the invention is characterized by a number of advantages over the prior art due to the design of the sieve shafts as conical sieve shafts with laterally projecting sieve blades.

[0025] The sieving device according to the invention combines the advantages of spiral shaft sieving devices and star shaft sieving devices, wherein the sieving device according to the invention consists of sieve shafts with pyramid-shaped sieve blades that form conical bodies of rotation when rotating, so that the feed material can always slide to the narrower end of the pyramid formed by the sieve blades or to the pyramid tip.

[0026] The screening device according to the invention is particularly suitable for separating feed material that tends to coil, achieving an improved separation result and, in particular, reducing or even completely preventing coiling of the screen shafts. A suitable design of the screen blades allows for self-cleaning effects, so that coiling of feed material around the screen shafts detaches from the shafts without manual intervention and is then carried away in the conveying direction. This means that the operation of the screening device according to the invention does not have to be stopped to manually remove feed material coiled around the screen shafts, resulting in lower maintenance and operating costs and increased efficiency.

[0027] Furthermore, the sieving device according to the invention is characterized by a very good sieving result when separating any solid mixtures, with efficient removal of oversize particles, a high degree of loosening or strong separation of the feed material, and intensive mixing of the feed material. In particular, it is possible to pull the feed material apart on the sieve shafts so that an approximately single-particle material layer can be formed. With suitable sieve shaft bearings and adjustability, the feed material can be pulled apart across the entire width of the sieve shafts. Extending the residence time of the feed material on the sieve shafts is also possible, which contributes to efficient separation of the feed material.

[0028] The screen shafts each have a plurality of laterally projecting or radially extending screen blades, preferably spaced equidistant from one another in the circumferential direction of the screen shaft. This enables a uniform distribution of the feed material on the screen shaft and efficient separation of the feed material.

[0029] In particular, the screen blades are arranged in a cross or star shape, oriented towards the axis of rotation of the screen shafts. This ensures effective separation of the feed material and effective self-cleaning of the screen shafts.

[0030] The longitudinal edges of the sieve blades preferentially form the lateral edges of a regular, straight pyramid. When the sieve shafts rotate, cone-shaped or conical bodies of revolution are thus produced.

[0031] In the case of shortening the sieve blades at one end of the sieve shaft in such a way that a frustoconical body of revolution is formed when the sieve shaft rotates, a shortening of the sieve blade tips by 1 cm to 10 cm, preferably 5 cm, can be provided.

[0032] The length of a sieve shaft can be between 1.0 m and 1.5 m, for example between 1.1 m and 1.2 m.

[0033] The screen blades have a triangular or trapezoidal contour, preferably a uniform contour. This shape of the screen blades helps to transport and separate the feed material towards the center of the separation deck as the screen shafts rotate. In particular, optimal utilization of the available screen blade area can be achieved. As the screen shafts rotate, conical bodies of revolution are formed, preferably with a straight generatrix from the base to the apex.

[0034] Two sieve blades can be formed by an identical flat sheet metal component as a base body. The base body can have a central recess or slot and, preferably, the contour of an isosceles triangle. Two base bodies can be interlocked by means of a complementary arrangement of the slots or recesses after one base body is rotated 180 degrees. Preferably, the base bodies can be welded together. In this way, a cross-shaped arrangement with four sieve blades can be easily obtained, which is stable and easy to assemble without requiring additional screws or bolts. In particular, the base bodies can be welded together.

[0035] For optimal separation, it is preferably provided that the screen blades extend longitudinally along the conical screen shafts, ideally over essentially the entire length of the shafts within the separation deck. This ensures maximum contact area between the feed material and the screen blades, which in turn can contribute to increasing the efficiency of the feed material separation.

[0036] The screen blades of adjacent screen shafts can be disengaged when the screen shafts rotate. However, to increase the interaction between the screen blades and the material being fed, it is also possible for the screen blades of adjacent screen shafts to interlock or mesh with each other when the screen shafts rotate. This can lead to more efficient screening and a more uniform distribution of the material across the screen surface.

[0037] Preferably, the axes of rotation of the screen shafts are aligned parallel to each other and / or can be aligned. The gaps between adjacent screen shafts can then have the same width. This results in a uniform separation across the entire length of the screen shaft.

[0038] To adjust the width of the screen gap or the screen space between the screen blades of adjacent screen shafts to the feed material, an adjustment mechanism for adjacent screen shafts relative to each other in the axial direction can be provided, in particular whereby screen shafts with different directions can be adjusted towards and away from each other. The adjustment of the screen gap width can be made, in particular, depending on the feed material. In particular, a design of the screening device according to the invention can be provided such that screen shafts with the same direction can be adjusted synchronously. Preferably, all screen shafts with the same direction can be adjusted together. The synchronous adjustability of the screen shafts leads to a consistent screening result over the entire length of the separation deck in the direction of the downstream screen shafts and enables a simple design of the screen shaft adjustment mechanism.

[0039] Synchronization of the screen shaft adjustment can be achieved using suitable mechanical, electrical, or electronic devices. For example, the screen shafts can be connected to a common drive, enabling simultaneous adjustment. Alternatively, the screen shafts can also be equipped with individual drives synchronized by a control unit.

[0040] Adjacent screen shafts can be arranged, or are to be arranged, in such a way that the axes of rotation of the screen shafts, in particular of all screen shafts, lie in a common, preferably horizontal, transport plane.

[0041] By tilting the screen shafts upwards and / or downwards, the angle of the screen shafts to the horizontal can be changed, and the material being fed onto the screen shafts can be spread out to a greater or lesser extent. According to the invention, adjacent screen shafts can be pivoted upwards and / or downwards, in particular, adjacent screen shafts can be pivoted towards or away from each other, and / or screen shafts with the same direction of rotation can be pivoted synchronously. This makes it easy to adjust the material being fed to a uniform width in the conveying direction of the subsequent screen shafts.

[0042] Tilting the screen shafts upwards directs the feed material more strongly outwards towards the cone base of the rotating body formed by the screen shaft's rotation, or towards the outer edge of the separating deck. The material width increases. Conversely, tilting the screen shafts downwards directs the feed material more strongly inwards towards the center of the separating deck.

[0043] In particular, the pivot angle between the axis of rotation of the respective screen shaft, in the raised or lowered position of the screen shaft, and a horizontal axis position of the screen shaft can be adjusted within a slope range of +0° to +45°, particularly up to +30°, and / or within a tilt range of -0° to -45°, particularly up to -30°. The positive sign refers to pivoting the screen shaft upwards with the cone pointing upwards, while the negative sign refers to pivoting downwards. This allows for a very effective change in the feed width of the material, with the greatest feed width being achieved transversely to the conveying direction of the material when the axes of rotation of the screen shafts are pivoted upwards relative to the horizontal axis position, particularly when the generatrix of the rotating body formed by the respective screen shaft during rotation is horizontally oriented.

[0044] Adjustable screen shafts allow the screening device to be adapted to different requirements dictated by the material being separated. This increases the flexibility of the screening device and enables optimal separation performance for a wide variety of materials.

[0045] For the synchronous adjustment of multiple screen shafts, two shaft supports can be provided, with each shaft support holding only screen shafts with the same direction of travel. Structurally, a separating deck is defined by the two shaft supports, positioned transversely to the conveying direction of the feed material.

[0046] Preferably, both wave carriers can be moved laterally to the conveying direction of the oversize material or in the direction of the rotation axes of the screen shafts and relative to each other, in particular, shifted, and together with the respective wave carrier, the screen shafts held on them can be moved. This allows influence on the screen gap width between adjacent screen shafts.

[0047] By pivoting the respective shaft carrier up and down around an axis transverse to the axis of rotation, the screen shafts held on it can be pivoted towards or away from each other, thus enabling a simple, synchronized pivoting motion of screen shafts in the same direction. As described above, this allows influence on the thrust width transverse to the conveying direction of the feed material.

[0048] The shaft supports can form side walls of the screening device according to the invention, optionally with further components, wherein the side walls are laterally supporting components of a screen box of the screening device and wherein the side walls can then be moved laterally towards and away from each other in the conveying direction of the oversize material or in the direction of the axes of rotation of the screen shafts and relative to each other, and / or pivoted up and down about an axis transverse to the axis of rotation. This allows the adjustability of the screen shafts relative to each other described above to be implemented in a simple manner.

[0049] The shaft supports can be adjusted by suitable mechanical devices, such as levers or hydraulic or pneumatic cylinders. Adjustment can be manual or automatic, for example, via a control unit. The adjustability of the shaft supports allows the position of the screen shafts to be adapted to the different requirements of the material to be separated. This increases the flexibility of the screening device according to the invention and enables optimal separation performance for a wide variety of materials.

[0050] Screen shafts with the same orientation are preferably held on one side by a shaft support. The screen shafts extend from their respective shaft supports inwards or towards the opposite shaft support, to which screen shafts with different orientations are held. The shaft ends or the conical tips of the rotating bodies formed by the rotation of the screen shafts are spaced apart from the respective opposite shaft supports, so that there is no risk of collision between the screen shafts and the opposing shaft supports.

[0051] The distance between opposing wave carriers can be between 1.1 m and 1.6 m, for example between 1.2 m and 1.3 m.

[0052] The shaft supports can be movable relative to each other, in particular wherein the shaft supports are preferably adjustable independently of each other transversely to the transport direction and / or preferably pivotable independently of each other about a pivot axis extending in the transport direction.

[0053] The screen shafts of a first shaft carrier and the screen shafts of a second shaft carrier can then be arranged laterally offset from each other, so that the conical apex of the conical bodies of revolution formed when the screen shafts rotate in a first direction faces the base surfaces or the respective conical base of the conical bodies of revolution formed when the screen shafts rotate in a second direction, and vice versa. In the transport or conveying direction, the screen shafts are then arranged alternately.

[0054] A drive device can be provided for driving the sieve shafts held and supported on the shaft carrier, wherein a control and / or regulation of the drive device can be provided such that the sieve shafts have the same rotational speed or different rotational speeds, in particular wherein the rotational speed increases or decreases in the conveying direction.

[0055] Different, alternating axle speeds can lead to better mixing of the feed material and thus to an improved screening result. Higher speeds of the screen shafts in the front section of the separating deck, where the material is fed onto the screen shafts, transport the feed material more quickly to the rear section and distribute it evenly across the screen shafts. However, the rotational speed of the screen shafts can also be higher in the front section of the separating deck than in the rear section.

[0056] The drive can be powered by an electric motor and a chain drive to the individual screen shafts. For stepless speed control, electric drives can be equipped with frequency converters. The speed and rotational speed can be optimally regulated for the material being screened. The rotational speed of the screen shafts can range from 60 rpm to 120 rpm or even higher.

[0057] Each shaft support can be assigned a separate drive arrangement, wherein a control and / or regulation of the drive device is provided in such a way that the sieve shafts held on the first shaft support with first direction and the sieve shafts held on the second shaft support with opposite second direction can be driven with the same rotational speed or with different rotational speeds.

[0058] A transverse deflection zone is formed between adjacent screen blades of a screen shaft, extending along the entire length of the screen blades in the direction of the screen shaft's axis of rotation. To subdivide the transverse deflection zone, at least one separating web, running transversely or obliquely to the axis of rotation, can be provided. This web is arranged between the adjacent screen blades and is preferably rigidly connected to them. By dividing the transverse deflection zone into several sub-zones, particularly long particles can be prevented from becoming lodged in the area between adjacent screen blades and then unintentionally passing through the gaps between the conical screen shafts. This significantly improves the screening result. Furthermore, a special shape of the webs allows the feed material to be actively conveyed against the incline of the conical screen shafts, thus extending the residence time on the screen shafts.to spread the feed material wider, so that an approximately single-grain material layer can be created.

[0059] In a preferred embodiment, several separating bars are arranged side by side in the circumferential direction of the screen shaft, in particular wherein the separating bars divide the transverse area into sub-spaces with different widths in the conveying direction of the feed material. To further improve the screening result, it can be provided that separating bars adjacent to both sides of a screen blade are arranged laterally offset from one another and / or are arranged on a preferably straight separation line.

[0060] The radial extent of the sieve blade can be greater than or equal to the radial extent of the separating bar. When the sieve shafts rotate, the separating bars then do not extend radially beyond the sieve blades.

[0061] The geometry of the flat side of the separating bar can be adapted to the geometry of the transverse area between two adjacent sieve sheets, in particular where the flat side of the separating bar can have a triangular contour.

[0062] Furthermore, the separating bar can be permanently connected to adjacent sieve blades, in particular by welding. The separating bar and the sieve blades are preferably made of sheet metal.

[0063] The number of ribs and the width of the separation zones or pockets formed by the ribs can be adapted to the properties of the workpiece. The sheet metal parts can be manufactured using laser cutting, which enables cost-effective production.

[0064] The screen blades and / or the separating bars can be made of metal, especially steel, or highly abrasion-resistant plastic, especially polyurethane. This reduces friction and wear on the screen blades and separating bars, and enables simple and cost-effective manufacturing of the screen shafts.

[0065] Particularly preferred is a single-sided bearing arrangement for the screen shafts at a shaft end located on the outside of the separating deck, or in the region of the cone base of the rotating bodies formed during rotation of the screen shafts. Multiple bearing arrangements for the shaft end are preferred. This results in high stability of the shaft bearing arrangement.

[0066] An embodiment of the invention is explained below with reference to the figures. Features that become apparent in the embodiment, both individually and in every combination of features, advantageously further define the subject matter of the claims in the above-explained manner. The figures show: Fig. 1 a perspective view of a sieving device according to the invention for separating solid mixtures as feed material according to particle size; Fig. 2 a top view of the sieving device Fig. 1; Fig. 3 the partial view III from Fig. 1 in an enlarged view; Fig. 4 the partial view III from Fig. 1, in which a wave carrier of the sieve device is freed; Fig. 5 a top view of detail V from Fig. 2, wherein shaft supports, drive and bearing parts of the sieve device are exempt; Fig. 6 a cross-sectional view of the sieving device Fig. 1 along the intersection line VI-VI; Fig. 7 a schematic top view of several sieve shafts of the sieve device according to the invention Fig. 1 with the first gap width of the sieve gaps formed between subsequent sieve shafts set; Fig. 8 a schematic top view of several sieve shafts of the sieve device according to the invention Fig. 1 with set second gap width of the sieve gaps formed between subsequent sieve shafts; Fig. 9 a schematic front view of two sieve shafts following each other in the conveying direction of the sieve device according to the invention Fig. 1 when the rotation axes are horizontally aligned; Fig. 10 a schematic front view of two sieve shafts following each other in the conveying direction of the sieve device according to the invention Fig. 1 after the sieve shafts have swung out relative to each other; Fig. 11. A perspective view of a sieve shaft of the sieve device. Fig. 1; Fig. 12 a top view of the sieve shaft from Fig. 11 with a view to a base disc of the sieve shaft; Fig. 13 a side view of the sieve shaft Fig. 11; Fig. 14 a side view of a second embodiment of a sieve shaft for the in Fig. 1 sieve device shown; Fig. 15 a top view of the sieve shaft from Fig. 14 with a view to a base disc of the sieve shaft; Fig. 16 a side view of a third embodiment of a sieve shaft for the in Fig. 1 sieve device shown and Fig. 17 a side view of a fourth embodiment of a sieve shaft for the in Fig. 1 sieve device shown.

[0067] The Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 to Fig. Figure 6 shows a screening device 1 for separating solid mixtures as feed material according to particle size. The screening device 1 has two side walls 2, 3 as lateral supporting components of a screen box of the screening device 1, which are connected to at least one crossbeam (not shown) and provide the necessary rigidity of the screen box.

[0068] The sieving device 1 further comprises a plurality of sieve shafts 4, 5 arranged downstream in a conveying or transport direction X of a feed material, wherein each sieve shaft 4, 5 rotates about its own axis of rotation Y, and wherein a feed material is transported in the conveying direction X according to the roller track principle and separated into a fine grain fraction and a coarse grain fraction.

[0069] The sieve shafts 4 and 5 are identical.

[0070] As can be seen on the Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15, Fig. 16 to Fig. 17 results in each sieve shaft 4, 5 having a plurality of sieve leaves 6. The longitudinal edges 7 of the sieve leaves 6 form the lateral edges of a right regular pyramid.

[0071] In the present embodiment, four sieve blades 6 are provided, which are arranged evenly distributed over the circumference of the sieve shaft 4, 5 and whose longitudinal edges 7 form the side edges of a straight square pyramid.

[0072] The screen shaft 4, 5 can also have two, three, or even more than four screen blades 6, which preferably have an equal distance from each other in the circumferential direction. For example, if three screen blades 6 are provided, arranged in a star shape around the axis of rotation Y of the screen shaft 4, 5, their radially outer longitudinal edges then form the lateral edges of a regular triangular pyramid. Alternatively, two screen blades 6 can be provided, which then lie in the same plane on both sides of the axis of rotation of the screen shaft 4, 5.

[0073] The longitudinal edges 7 of the sieve blades 6, when the sieve shafts 4, 5 rotate, form the lateral surface of a cone-shaped body of revolution extending from a cone base to a cone apex. The cone base is located at the shaft end where the sieve blades 6 have their maximum radial extent. The radial extent of the sieve blades 6 then decreases towards the cone apex, with the sieve blades 6 having their smallest radial extent at the apex. The longitudinal edges 7 of the sieve blades 6 then form the generatrix of the cone-shaped body of revolution, with the generatrix connecting the cone base to the cone apex.

[0074] The flat sides of the sieve sheets 6 accordingly have the contour of a right-angled triangle. By rotating the sieve sheets 6 around the legs of the right-angled triangle formed by the contour line, which are arranged parallel to the axis of rotation, a cone-shaped solid of revolution is obtained.

[0075] An embodiment in which the sieve blades 4, 5 have a trapezoidal contour is not excluded, so that a frustoconical body of revolution is formed when the sieve shafts 4, 5 are rotated.

[0076] On the conical screen shafts 4, 5 thus formed, the feed material is transported in the conveying direction X according to the roller conveyor principle and separated into a fine and a coarse fraction. Due to the downward slope of the screen shafts 4, 5 towards the center of the screen box, the wrapping of the screen shafts 4, 5 by feed material that tends to wrap around them is largely prevented, whereby, with the rotation axes Y of the screen shafts 4, 5 arranged horizontally, the feed material is conveyed inwards, i.e., towards the center of the formed separation deck. The inclination of the screen blades 6 towards the cone apex of the rotating bodies formed by the rotation of the screen shafts results in a self-cleaning effect of the screen shafts 4, 5, so that manual removal of feed material, such as rolled material and / or film material, from the screen shafts 4, 5 is not necessary, or at least occurs less frequently than with known spiral shaft and star shaft screens.This results in lower maintenance and operating costs.

[0077] Furthermore, the sieve blades 6 on the sieve shafts 4, 5 ensure efficient removal of oversize material with a high degree of loosening or strong separation, as well as thorough mixing of the feed material. The sieving device 1 is therefore characterized by an improved sieving result.

[0078] In the illustrated embodiment, the longitudinal edges 7 of the sieve blades 6 have a straight course, with the radial extent of the sieve blades 6 decreasing from a shaft end, where the sieve blades 6 have their maximum radial extent and where the cone base of the body of revolution formed by rotation of the sieve shafts 4, 5 is located, towards an opposite free shaft end, where the sieve blades 6 have their smallest radial extent and where the cone apex of the body of revolution is located. An embodiment in which the longitudinal edges 7 of the sieve blades 6 have a non-straight course from the cone base to the cone apex is not excluded.

[0079] In the illustrated embodiment, the sieve blades 6 are essentially tapered to a point towards the free end of the sieve shaft 4, 5. An end piece 8 is provided at the free end of the sieve shafts 4, 5, which abuts the tips of the sieve blades 6. However, in a welded construction, the end piece 8 can be omitted. Likewise, the sieve blades 6 can be welded directly to one another without the use of a [missing element]. Fig. 11 polygonal profile tubes shown.

[0080] The screen shafts 4, 5 are arranged in the conveying direction X of the feed material with alternating orientations. The term "orientation" refers to the extent of the screen shafts 4, 5 extending from a conical base of the rotating body formed by the rotation of the respective screen shaft 4, 5, where the screen blades 6 have their greatest radial extent, towards a conical apex of the rotating body, where the screen blades 6 have their smallest radial extent. In other words, the conical apex of the rotating bodies formed by the rotation of the screen shafts 4, 5 alternately points to the left and to the right. In the illustrated embodiment, the conical apex of the rotating bodies formed by the rotation of the screen shafts 4, 5 points to the left, while the conical apex of the rotating bodies formed by the rotation of the screen shafts 5 points to the right.

[0081] As can be seen in particular from the Fig. 7 and Fig. As the sieve shafts 4 and 5 rotate, gaps 9 are formed between the sieve blades 6, through which a fine-grained fraction falls downwards into a receiving chamber 10 during the sieving process. A coarse-grained fraction is transported via the sieve shafts 4 and 5 by the roller conveyor effect in the conveying direction X to an open end 11 of the sieving device 1 and exits the separating deck there. With the design shown, the sieve shafts 4 and 5 constantly clean each other of deposits and snags.

[0082] To adjust the gap width 12 of the sieve gaps 9, adjacent sieve shafts 4, 5 can be adjusted relative to each other in the axial direction, whereby sieve shafts 4, 5 can be adjusted towards and away from each other in different directions. As can be seen from the Fig. 7 and Fig. As further shown in section 8, the axes of rotation Y of the sieve shafts 4, 5 can be adjusted parallel to each other. By moving the sieve shafts 4, 5 towards each other in opposite directions, the gap width 12 of the sieve gaps 9 decreases, while it increases when the sieve shafts 4, 5 move apart in the direction of the axes of rotation Y. It is preferably provided that sieve shafts 4, 5 can be adjusted synchronously in the same direction.

[0083] The possible adjustment movement of the sieve shafts 4, 5 in the direction of the axes of rotation towards each other and away from each other is shown in the Fig. 7 and Fig. 8 shown by movement arrows 13.

[0084] How further developments will emerge Fig. 9 results in adjacent sieve shafts 4, 5 being aligned or alignable such that the axes of rotation Y of the sieve shafts 4, 5 lie in a common, preferably horizontal, conveying plane.

[0085] Out of Fig. It follows from paragraph 10 that adjacent screen shafts 4, 5 can also be mounted so that they can pivot up and down, wherein adjacent screen shafts 4, 5 can pivot towards or away from each other in different directions, and, in particular, wherein screen shafts 4, 5 can pivot synchronously in the same direction. The pivotability of the screen shafts 4, 5 is in Fig. 10 schematically shown by movement arrows 14, wherein the swivel angle a between the rotation axis Y of a sieve shaft 4, 5 in the up or down swiveled state of the sieve shaft 4, 5 and a horizontal axis position can be adjusted in a slope range of + 0° to + 45°, in particular up to + 30°, and / or in a tilt range of - 0° to - 45°, and / or up to - 30°.

[0086] Each sieve shaft 4, 5 is supported on one side with a shaft end 16 on a shaft support 17, wherein sieve shafts 4, 5 with the same direction of travel are supported on the same shaft support 17.

[0087] The shaft supports 17 and thus the sieve shafts 4, 5 mounted on the shaft supports 17 are adjustable in the direction of the axes of rotation Y and can be pivoted up and / or down about an axis transverse to the axis of rotation Y.

[0088] In particular, the side walls 2, 3, as laterally supporting components of the sieve box of the sieve device 1, together with the shaft supports 17 and the sieve shafts 4, 5 mounted on the shaft supports 17, can be adjusted towards each other and away from each other in the direction of the axes of rotation Y and / or pivoted up and / or down about an axis transverse to the axis of rotation Y.

[0089] For support, each screen shaft 4, 5 has a shaft flange 18 which is connected via a shaft journal 33 to a base plate 25 of the screen shaft 4, 5. The base plates 25 serve as supports for the screen blades 6 and ensure stable mounting as well as even load distribution on the screen shaft 4, 5.

[0090] The shaft flange 18 is connected to a flange disc 32 of a bearing piece 19 for force and torque transmission. The connection can be made via a bolted joint.

[0091] The bearing piece 19 is supported twice by bearing elements 20 and 21. The double support results in increased stability, better load distribution, and helps to compensate for tilting moments.

[0092] As can be seen from Fig. As 6 results, the shaft support 17 is integrated into the cheek housing 15 of the respective side cheek 2, 3. All sieve shafts 4, 5 are mounted on the respective shaft support 17 with the same direction of rotation.

[0093] The cheek housing 15 is designed as a sheet metal part and has an outer housing section 22 and an upper housing section 23.

[0094] The inner end is formed by a side panel 24, which can be made of plastic and is connected to the upper housing section 23. The side panel 24 prevents feed material from entering the side wall housing 15 of the respective side wall 2, 3 via the screen shafts 4, 5.

[0095] Circular openings for the base discs 25 of the sieve shafts 4, 5 are provided in the side panel 24.

[0096] The drive of the sieve shafts 4, 5 is provided by hardened sprockets 26 and reinforced roller chains, which are arranged in the cheek housing 15 between the shaft carrier 17 and the outer housing section 22 of the cheek housing 15 and are thus encapsulated in the cheek housing 15 and protected from interference and contamination.

[0097] The shaft drive can be powered via an electric motor and a chain drive to the individual screen shafts 4, 5, although this is not shown in detail. A drive housing 27 is provided at a closed end 28 of the screen box of the screening device 1 to accommodate the drive with electric motor and drive sprocket. The speed and rotational speed of the screen shafts 4, 5 can be optimally controlled and / or regulated for the material being screened. In particular, it is provided that the drive is controlled and / or regulated such that the screen shafts 4, 5 can have the same rotational speed or different rotational speeds, especially where the rotational speed can increase or decrease in the conveying direction X.

[0098] Each shaft support 17 is preferably assigned a separate drive, wherein a control and / or regulation can be provided such that the sieve shafts 4 held on the first shaft support 17 can be driven with the first direction of rotation and the sieve shafts 5 held on the second shaft support 17 can be driven with the opposite second direction of rotation at the same rotational speed or at different rotational speeds.

[0099] The area between two adjacent sieve blades 6 following each other in the circumferential direction of a sieve shaft 4, 5 forms a transverse laying area 29 of a sieve shaft 4, 5 extending in the direction of rotation Y over the entire length of the sieve blades 6 ( Fig. 11, Fig. 12 to Fig. 13).

[0100] To divide the transverse laying area 29 into several separation areas 30 with a smaller width or extension in the direction of rotation Y compared to the entire transverse laying area 29, separating webs 31 arranged transversely or obliquely to the axis of rotation Y can be provided between the adjacent sieve blades 6 ( Fig. 14, Fig. 15, Fig. 16 to Fig. 17). The separating bars 31 prevent long parts in the feed material from passing through the screen gaps 9 between the screen shafts 4, 5.

[0101] In the embodiments shown, the separating areas 30 have different widths or extensions in the direction of the axis of rotation Y. It is also possible that the separating webs 31 are spaced equidistant from each other in the longitudinal direction of the sieve shafts 4, 5.

[0102] The radial extent of the sieve sheets 6 is preferably always greater than or equal to the radial extent of the separating webs 31 ( Fig. 15). The separating bars 31 do not extend beyond the sieve leaves 6 in a radial direction.

[0103] Furthermore, the separating webs 31 in the illustrated embodiments have a triangular contour.

[0104] The separating bars 31 can be permanently connected to the sieve sheets 6, in particular welded.

[0105] Dividing bars 31 adjacent to both sides of a sieve sheet 6 can be arranged on a preferably straight dividing line ( Fig. 14, Fig. 15) or be arranged offset from each other ( Fig. 16).

[0106] Slantly arranged separating bars 31, which border a sieve sheet 6 and lie on a slanted separating line, show Fig. 17.

[0107] By using a suitable shape for the separating bars 31, the feed material can be actively conveyed against the slope of the sieve sheets 6 in order to extend the residence time of the feed material on the sieve sheets 6 or to spread the material more widely.

[0108] The connection of the sieve sheets 6 to each other and / or to the separating bars 31 can be achieved by material bonding, in particular by welding.

[0109] Furthermore, the sieve sheets 6 and / or the separating bars 31 can be made of metal, in particular steel, or of an abrasion-resistant plastic, in particular polyurethane.

[0110] The length-to-width ratio of the sieve shafts 4, 5 is chosen only as an example. The sieve shafts 4, 5 may have a length-to-width ratio that differs from the one shown. The aforementioned length-to-width ratio of the sieve shafts 4, 5 refers to the maximum extension length l of the sieve blades 6 from the base disk 25 to the end piece 8 and the maximum extension width b of the sieve shafts 4, 5, which corresponds to the maximum edge distance of two sieve blades 6 arranged in a common plane transverse to the axis of rotation at their outer corners adjacent to the base disk 25. This is in Fig. 13 shown schematically.

[0111] The production of the sieve shafts 4, 5 can be carried out, for example, as follows: For example, a sheet metal part forming two adjacent sieve blades 6 lying in a common plane can be welded to the base disc 25. The base disc 25 can be connected to the shaft flange 18 via the shaft journal 33, in particular by welding. Further sieve blades, arranged perpendicular to the sheet metal part in the region of the central longitudinal axis, are then welded to the sheet metal part, so that the Fig. The welded construction shown in section 11 results. This is shown in Fig. The medium polygonal profile tube shown in section 11 does not necessarily have to be provided.

[0112] However, it is also possible to place a welded assembly, consisting of a polygonal profile tube, the shaft flange 18, the shaft journal 33, and the base plate 25, into a casting mold and then cast the sieve blades 6 completely onto the welded assembly. Other methods for manufacturing the sieve shafts 4, 5 are possible. Reference symbol list: 1 sieve device 2 side cheek 3 Side cheek 4 sieve shaft 5 sieve shaft 6 sieve sheets 7 Long edge 8 End piece 9 sieve gap 10 Recording room 11 End 12 gap width 13 Arrow 14 Arrow 15 cheek cases 16 Wave end 17 wave carriers 18 wave flange 19 stock items 20 Bearing part 21 Bearing part 22 Housing section 23 Housing section 24 side panels 25 Base plate 26 sprocket 27 Drive housings 28 End 29 Cross laying area 30 separation area 31 dividing bridge 32 Flange washer 33 wave-shaped pins

Claims

Screening device (1) for separating solid mixtures as feed material according to particle size, in particular for separating difficult-to-screen, moist and / or sticky and / or coiling material, such as household and commercial waste, mixed construction waste, rubble, excavated soil, stockpile material from landfill remediation, alternative fuels, coiled goods and / or film and / or wire goods, biowaste, compost, waste wood, wood, green waste, with a plurality of screen shafts (4, 5) arranged downstream of the feed material in a conveying direction, wherein each screen shaft (4, 5) rotates about its own axis of rotation and wherein the feed material is transported on the screen shafts (4, 5) in the conveying direction according to the roller conveyor principle and is separated into a fine-grained fraction and a coarse-grained fraction, characterized in that the screen shafts (4, 5) are designed as conical screen shafts with laterally projecting screen blades (6) which, when the screen shafts (4, 5) rotate form cone-shaped bodies of revolution,wherein the screen shafts (4, 5) are arranged in the conveying direction of the feed material with alternating directions and wherein, when the screen shafts (4, 5) rotate, screen gaps (9) are formed between the screen blades (6) of adjacent screen shafts (4, 5) for separating the feed material. Sieve device (1) according to claim 1, characterized in that each sieve shaft (4, 5) has a plurality of radially projecting sieve leaves (6), wherein the sieve leaves (6) are spaced equally apart from each other in the circumferential direction of the sieve shaft (4, 5) and / or wherein longitudinal edges (7) of the sieve leaves (6) form the side edges of a regular straight pyramid and / or wherein the sieve leaves (6) have the same sieve leaf contour, in particular a triangular contour or trapezoidal contour. Sieve device (1) according to one of the preceding claims 1 or 2, characterized in that the axes of rotation of the sieve shafts (4, 5) are aligned parallel to each other or can be aligned and / or adjusted, in particular wherein adjacent sieve shafts (4, 5) are adjustable relative to each other in the direction of the axes of rotation, further in particular wherein sieve shafts (4, 5) with different directions are adjustable towards each other and away from each other, further in particular wherein sieve shafts (4, 5) with the same direction are adjustable synchronously. Sieve device (1) according to one of the preceding claims, characterized in that adjacent sieve shafts (4, 5) can be aligned such that the axes of rotation of the sieve shafts (4, 5) lie in a common, preferably horizontal, conveying plane, in particular wherein adjacent sieve shafts (4, 5) can be pivoted up and / or down, further in particular wherein adjacent sieve shafts (4, 5) can be pivoted towards or away from each other and / or wherein sieve shafts (4, 5) can be pivoted synchronously in the same direction. Sieve device (1) according to one of the preceding claims, characterized in that two shaft supports (17) are provided for holding the sieve shafts (4, 5), wherein only sieve shafts (4, 5) with the same direction of travel are held on each shaft support (17) and the sieve shafts (4, 5) of the first shaft support (17) and the sieve shafts (4, 5) of the second shaft support (17) are arranged alternately in the conveying direction and wherein, preferably, the sieve shafts (4, 5) are synchronously adjustable in the direction of the axes of rotation by an adjustment movement of at least one shaft support (17), in particular of both shaft supports (17) and / or wherein the sieve shafts (4, 5) are synchronously pivotable up and / or down by a pivoting movement of at least one shaft support (17), in particular of both shaft supports (17) about an axis transverse to the axis of rotation. Sieve device (1) according to one of the preceding claims, characterized in that the sieve shafts (4, 5) are each mounted on one side on a shaft carrier (17), wherein, preferably, the sieve shafts (4, 5) are mounted multiple times on one side. Sieve device (1) according to one of the preceding claims, characterized in that at least one separating web (31) arranged transversely or obliquely to the axis of rotation of the sieve shaft (4, 5) is provided between two adjacent sieve blades (6) following in the circumferential direction of a sieve shaft (4, 5) for dividing a transverse laying area (29) formed between the adjacent sieve blades (6) over the longitudinal extent of the sieve blades (6) into several separation areas (30). Sieve device (1) according to one of the preceding claims, characterized in that between two sieve sheets (6) following in the circumferential direction of a sieve shaft (4, 5) several separating webs (31) arranged transversely or obliquely to the axis of rotation are provided for dividing a transverse laying area (29) formed between the adjacent sieve sheets (6) over the longitudinal extent of the sieve sheets (6) for feed material into several separation areas (30) of different widths and / or that separating webs (31) adjoining a sieve sheet (6) on both sides are arranged laterally offset from each other and / or are arranged on a preferably straight separation line. Sieve device (1) according to one of the preceding claims, characterized in that the radial extent of the sieve sheets (6) is greater than or equal to the radial extent of the separating web (31) and / or the separating web (31) has a triangular contour and / or the separating web (31) is inseparably connected to the sieve sheets (6), in particular welded. Sieve shaft (4, 5) for a sieving device (1) according to one of the preceding claims for separating solid mixtures as feed material according to particle size.

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