FEEDING DEVICE FOR BELT CONVEYORS

Abstract: A goods-feeding device for a belt conveyor, especially of the type having a conveyor belt flexible in the transverse direction, has a roller (10) which in the circumferential direction is partially enclosed by a goods-carrying side of the belt of the conveyor and which forms a gap with respect to said side of the belt between the edges thereof. The roller (10) is designed with a plurality of surface areas engaging the roller-enclosing side of the belt and supporting the belt both centrally and at the edges thereof, the roller (10) having in its central part one or more discs (14) forming the central supporting surface areas.

Description: FEEDING DEVICE FOR BELT CONVEYORS The present invention relates to a goods-feeding device for a belt conveyor, especially of the type having a conveyor belt which is flexible in the trans¬ verse direction. It is previously known to accelerate goods trans¬ ported on a conveyor belt by making the belt pass over a so-called disc roller which in the circumferen¬ tial direction is partially enclosed by the goods- carrying side of the belt of the conveyor and which further forms a gap with respect to said side of the belt between the edges thereof (see SE Patent Applica¬ tion 8301822-6). This known disc roller however requires a belt having flexural rigidity in the transverse direction, which means that the flow of goods tends to diverge and also makes the known disc roller use¬ less in connection with transversely flexible belts, such as are used e.g. in belt conveyors having twisted belts. The object of the present invention is to provide a goods-feeding device which permits accelerating the goods without this spreading or diverging, i.e. which maintains a concentrated flow of goods, and which is usable in a belt conveyor having twisted belts and especially as goods feeder in such belt con- veyors. These and other objects of the invention are achieved by means of a feeding device which is of the type stated in the introduction to this specifi¬ cation and which is characterized in that the roller is formed with a plurality of surface areas engag¬ ing the roller-enclosing side of the belt and sup¬ porting the belt both centrally and at the edges there¬ of and allowing conveyance of goods radially into and out of the roller. According to a particularly advantageous aspect of the invention, the roller has in its central part one or more discs forming said central supporting surface areas. These discs which should have a considerably smaller thickness than diameter contribute to accelerating the goods and maintaining the distribution of the goods ' transversely of the belt, even if the shaft of the roller is in¬ clined. Embodiments of the device according to the inven- tion will be described in greater detail hereinbelow with reference to the accompanying drawings. Fig. 1 shows a preferred embodiment of a roller according to the present invention usable as a feeding device. Fig. 2 is a side view of the roller with the associated conveyor belt. Fig. 3 illustrates an embodiment of the device according to the invention used in a single- belt conveyor having a twisted belt throughout the path of conveyance. Fig. 4 illustrates the use of the device according to the invention in a double-belt conveyor. Fig. 5 shows a further embodiment of the feeding device according to the invention. Fig. 6 is a top plan view of the device shown in Fig. 5. Fig. 7 is a cross-sectional view taken along the line A-A in Fig. 6. Figs. 8-10 show examples of the use of the inventive device as a feeder. As shown in Fig. 1, the conveyor belt roller 10 according to the invention has a shaft 11 on the outer ends of which two wheels 12 and 13 are mounted. Between the wheels, three discs 14 are mounted on the shaft 11. Thus, the peripheral surface of the roller is divided into axially separated sections, the wheels 12, 13 and the discs 14 each having a re¬ spective peripheral surface area. The embodiment of the roller 10 as illustrated in Fig. 1 is particularly advantageous, but other embodiments of the roller are conceivable within the scope of the invention as long as the roller forms a gap with respect to the roller-enclosing side of the belt between the edges of the belt and is designed with surface areas which engage said enclosing side of the belt and support the belt both centrally and at the edges thereof and allow the goods to pass ra¬ dially into and out of the roller, i.e. through the gap defined by the roller. Thus, the roller should have spaces radially inwardly of its peripheral sur¬ face for the passage of material conveyed, and the surface areas should be such that the material can pass radially into and out of these spaces. It goes without saying that the roller according to the invention is usable for instance as a deflec¬ tion roller for transferring goods between different parts of a belt conveyor running in different directions, without necessitating any reloading, as on- or infeed roller or outfeed roller. In the configuration shown in Fig. 2, a roller 10 according to the invention is used in combination with a conveyor belt 15 which partially encloses the roller 10. The belt 15 leaves the roller 10 in a di¬ rection 16 which is the desired direction of flow of the goods. The goods are fed into the roller 10 through the periphery within a sector designated by arrows 17. The goods can also be supplied at an angle to a portion 19 of the belt 15. In such a case, the goods will be entrained by the belt 15 towards the roller 10 and into the spaces 20 defined between the wheels 12, 13 and the discs 14 of the roller. When the belt 15 changes its direction of travel on the roller 10, the goods will be flung by the centrifugal force radially outwardly against the side of the belt 15 facing the roller 10 and will there follow the belt 15 while exerting an increased pressure thereon. The goods can also be guided along the belt por¬ tion 19, for instance by being supported and entrained by the belt 15 towards the roller 10. The process in the roller 10 will then be substantially the same as described above. To conclude, the flow of goods is thus guided towards or along a portion 21 of the path of travel of the conveyor belt 15, which thereafter changes its direction of travel, especially by following the periphery like the portion 21, such that the goods are subjected to a centrifugal force directed towards the conveyor belt 15 and. the pressure of the goods against the conveyor belt 15 increases. Since, in the illustrated example, the portion 21 also produces a change of the direction of travel of the conveyor belt 15, the goods will be subjected, also within the portion 21, to a centrifugal force directed towards the conveyor belt 15, with an ensuing increase of the pressure of the goods against the belt. It- should be emphasized that the arrangement of the discs 14 provides a support for the central parts of the belt 15 between the edges thereof, so that a transversely flexible conveyor belt 15 can be used, which is especially advantageous in belt conveyors having twisted belts. When the roller is used as a feeder roller, the goods can thus be supplied to the roller radially, with or without a tangential component of. motion. To this end, it is possible, in the simplest case, to use a hopper or funnel together with a suitable feeding mechanism, such as a screw conveyor, which raises the goods in the funnel so as to be fed into the feeder roller. Both screw conveyors and conveyors of other types can of course be used in different combinations with the feeder roller, as will be under¬ stood from the following. In Fig. 3, there is shown a single-belt conveyor having two rollers 10 according to the invention. The undulatory line in Fig. 3 indicates that the belt is twisted about its own axis so as to form a tube. both between the rollers 10 according to the invention and between the upper of these rollers and an end roller 22. The goods are here supplied at the lower roller 10, as indicated by an arrow 23, and is dis- charged in a conventional manner over the end roller 22, as indicated by an arrow 24. The upper roller 10 in Fig. 3 operates in the manner shown in Fig. 2 but with a vertical direction of infeed of the goods and a horizontal direction of outfeed of the goods. Fig. 4 illustrates the use of the device according to the invention in a double-belt conveyor where the goods are transported between two belts. From the point of outfeed to the point of infeed of the goods, the belts in this case are returned in a substantially planar state. In both cases, the infeed takes place by means of the conveyor belt roller 10 according to the invention at the point indicated by the arrow 23. In this case, a guide roller 25 is a conventional roller over which the goods are transported between the two belts. The belt conveyors illustrated in Figs. 3 and 4 " are schematically illustrated. In a practical embodi¬ ment, the conveyor in Fig. 3, for example, normally requires further rollers for guiding the belt along the desired path of travel which seldom is in a single plane. Fig. 5 shows an embodiment where three rollers 10 are used. An embodiment using still further rollers 10 located adjacent each other is also possible. To prevent large pieces of goods from coming in between the belt 15 and the peripheral surfaces of the rollers 10, it is possible according to Figs. 5-7 to provide U-shaped baffles 27 in a bridging fashion between the discs 14 of the rollers 10. Similarly, baffles 28 can be provided at the inner sides of the wheels 12 and 13 of the rollers 10, such that material pass¬ ing through the rollers 10 will be prevented from coming in between the belt 15 and the peripheral sur¬ faces of the wheels 12, 13 and of the discs 14. In Fig. 8, there is shown a variant of the combi¬ nation of a bucket elevator and the roller 10 according to the invention. The axis of rotation of the bucket elevator 29 is substantially parallel to the shaft 11 of the roller 10, and the bucket elevator 29 feeds the goods into the roller 10 through a radially and axially directed chute 30. Instead of the bucket elevator 29 in Fig. 8, it is possible to use a vertically mounted screw con¬ veyor 31, as shown in Fig. 9. The screw conveyor 31 can then feed the goods into the roller 10 in the same manner as the bucket elevator 29 in Fig. 8. Fig. 10 illustrates a practical embodiment of the combination of a screw conveyor 32 and a single- belt conveyor 33 having a roller 10 according to the invention. In this case, the screw conveyor 32 is provided at its lower end with a per se known feeder 34 and is driven by a shaft 35 which extends substan¬ tially parallel to the belt 36 of the belt conveyor 33. Both the upward and the downward run of the belt 36 are twisted about their own axis so as to form a tube for vertical conveyance of goods. From the screw conveyor, the goods are conducted through an ejector tube 37 radially into the roller 10 which causes the goods to follow the upward belt run and pass into the tube formed by it. The lower end of the tube is open to the roller 10 and to ensure that the goods will follow the belt conveyor upwardly, a hood 38 can be provided for closing the opening of the tube, except to the roller 10. In a further variant, the shaft of the roller 10 can be divided, with the different parts disposed at an angle to each other. In this way, the extension of the belt in the transverse direction can be guided to some extent during the passage of the belt over and in connection with the roller, which may sometimes be desirable. At least one of the wheels 12, 13 may also be an idler wheel mounted on the shaft 11 by means of a spherical ball bearing, and the discs 14 may serve to guide the belt. In this case, the discs 14 may have a certain flexibility along their periphery. The shaft of the roller 10 may also be divided in such a manner that the axially central part of the roller, e.g. the discs 14 or a further wheel, can be removed and reinserted in the radial direction. This can be done, for example in an initial phase, especially for supporting the central part of the belt or for allowing large pieces of material to pass through. It is evident that the roller according to the invention can be used for all types of belt conveyors, for instance belt conveyors having a single planar belt and belt conveyors having two belts cooperating for the conveyance of the goods, but it is especially useful for belt conveyors having twisted belts. The roller according to the invention thus aims at im¬ parting a convex shape to the belt when enclosing the roller, with a view to achieving self-alignment of the belt on the roller, providing sufficient space for receiving the goods conveyed, accelerating the goods, and maintaining the distribution of the goods across the width of the belt. Finally, it goes without saying that the device according to the invention is useful in any belt con- veyor type and that the embodiments described above should only be regarded as examples of the invention.

Claims: CLAIMS 1. A goods-feeding device for a belt conveyor, especially of the type having a conveyor belt flexible in the transverse direction, said device comprising a roller (10) which in the circumferential direction is partially enclosed by a goods-carrying side of the belt (15) of the conveyor and which forms a gap in relation to said side of the belt between the edges thereof, c h a r a c t e r i z e d in that the roller (10) is formed with a plurality of surface areas engag- ing said roller-enclosing side of the belt and support¬ ing the belt both centrally and at the edges thereof and allowing conveyance of goods radially into and out of the roller. 2. Device as claimed in claim 1, • c h a r a c - t e r i z e d in that the roller (10) in its central part has one or more discs (14) forming said central supporting surface areas. 3. Device as claimed in claim 1 or 2, c h a ¬ r a c t e r i z e d in that the shaft (11) of the roller (10) is axially divided. 4. Device as claimed in claim 3, c h a r a c ¬ t e r i z e d in that the shaft is divided into two parts which are disposed at an angle to each other. 5. Device as claimed in one any of claims 1-3, c h a r a c t e r i z e d in that an axially central part of the roller is movable in the radial direction between a position in contact with and another position out of contact with the belt. 6. Device as claimed in claim 2, c h a r a c - t e r i z e d by at least one further roller (10) of the same design, baffles (27, 28) being provided between each pair of rollers to prevent goods from coming in between the belt (15) and the peripheral surfaces of the discs (14). 7. Device as claimed in any one of claims 1-6, c h a r a c t e r i z e d in that the surface areas of the roller (10) constitute part of the surface of a cambered cylinder. 8. Device as claimed in any one of claims 1-7, c h a r a c t e r i z e d by a goods feeder (29, 31, 32) for radially feeding goods into the interior of the roller (10) serving as infeed means. 9. Device as claimed in claim 8, c h a r a c - t e r i z e d in that the goods feeder is a screw conveyor (31, 32 ) .

Inventors: LOODBERG JAN AOKE TORSTEN, WALL ARNE EVERT, LOODBERG, JAN, AOKE, TORSTEN, WALL, ARNE, EVERT
Applicants: SCANIAINVENTOR AB, AB SCANIAINVENTOR
Application year: 1985
Main classification: B65G15
IPC codes: B65G15, B65G47, B65G65