WO2010136635A1

WO2010136635A1 - Pulley for a conveyor, apparatus and method

Info

Publication number: WO2010136635A1
Application number: PCT/FI2009/050452
Authority: WO
Inventors: Jouni Rajala; Pasi NÄSE
Original assignee: Metso Minerals Oy
Current assignee: Metso Finland Oy
Priority date: 2009-05-28
Filing date: 2009-05-28
Publication date: 2010-12-02
Anticipated expiration: 2011-11-28

Abstract

A pulley for a conveyor, comprising a rotatable shell (13), to the shell surface (14) of which cantilevers (2,20) are attached for supporting a conveyor belt on an exterior perimeter (3) of the pulley defined by the cantilevers (2,20). In the pulley (200,201,202) two sequential cantilevers are arranged such that the distance between said cantilevers is increase from the middle (200.1,201.1,202.1) of the pulley to the direction of both ends (200.2,201.2,202.1) of the pulley. An apparatus comprising a pulley according any embodiment of the invention, preferably a crushing plant (300). A method for processing material with the pulley.

Description

PULLEY FOR A CONVEYOR, APPARATUS AND METHOD

FIELD OF THE INVENTION

The invention relates to a pulley for a conveyor. Particularly, though not exclusively, the invention relates to a self-cleaning pulley of a belt conveyor.

BACKGROUND OF THE INVENTION

In belt conveyors, a conveyor belt encircles around conveyor pulleys. Self-cleaning pulleys are used in conveyors for stone material and sand. In self-cleaning pulleys, when leaving the pulley, sand and stones move in the direction of the radius of the pulley. Several metallic parts are needed, welded together, for achieving the cleaning effect. Typically, in manufacturing the pulley there is a lot of welding work. The surface of the pulley is typically metallic. In large rib pulleys, there are structural solutions available where a rubber wearing part is placed on the surface of the rib of the metallic pulley.

Said folding pulley 100 presented in Figs. 1 and 2 comprises a rigid axle 1 , to which plate structured wings 2 are attached. Fig. 1 presents the pulley 100 as a perspective figure and Fig. 2 presents the pulley of Fig. 1 from the end. Wings 2 are of the width of the conveyor belt on an exterior perimeter 3 of the pulley 100, which exterior perimeter is presented with a dotted line in Fig. 2. The rotation direction of the pulley is presented with an arrow 15. The wing 2 comprises a vertical part 4, which comprises a first surface 5 and an orbicular part 7 attached to an outer edge 6 of the vertical part 4, which orbicular part is in an angular position in relation to the vertical part 4. The orbicular part 7 comprises a second surface 8 in contact with the conveyor belt, which second surface is curved in the direction of the exterior perimeter. The second surface 8 has a curvature radius corresponding with the curvature radius of the exterior perimeter 3. The second surfaces 8 of the wings 2 form the intermittent circular exterior perimeter 3 of the pulley 100. Stones and sand may leave the pulley 100 through gaps 9 of somewhat even width, formed by adjacent wings 2 between them. Each gap 9 is formed between a free brim 10 of the orbicular part 7 of the first wing and the first surface 5 of the second wing.

The vertical part 4 of each wing 2 is attached to the axle 1 from its interior straight brim by welding such that the first surface 5 of the vertical part 4 is parallel with the axle 1 and the vertical part 4 protrudes from the axle 1 in the direction of the radius of the axle. The vertical part 4 is formed of two parts 4.1 and 4.2 which are attached to each other in the middle point of the pulley and are mirrors of each other. For forming a diameter of the exterior perimeter 3 of the pulley 100 greater in the middle point 100.1 of the pulley than in the ends 100.2, the height of the vertical part 4 in the direction of the radius of the pulley 100 in the ends 100.2 is smaller than in the middle point 100.1. The orbicular part 7 is welded from its interior area 11 to the exterior brim 6 of the vertical part 4. The curvature radius of the orbicular part of the interior area 11 is smaller than on the outer surface 8 of the orbicular part 7, which orbicular part ends in the free brim 10.

In the pulley 100, shell parts 13 are attached between adjacent wings 2 by welding. An exterior shell surface 14 of the shell part 13 comprises shell portions 14.1 and 14.2 which are inclined from the middle 100.1 of the pulley to the direction of the ends 100.2. Inside the pulley i.e. between the wings 2, a stone moves slowly along the inclined shell portions of the shell surface 14 from the middle 100.1 of the pulley to the direction of the ends 100.2. The shell part 13 comprises a symmetric plate structure, which comprises plate parts which are wider in the middle of the pulley than in the ends, to make the diameter of the intermittent shell perimeter formed together by the shell surfaces 14 greater in the middle of the pulley than in the ends. The shell part 13 is welded to the first surface 5 of the vertical part 4 of the first wing 2 from its first brim 13.1 and to the second surface 12 of the second vertical part 4 of the second wing 2 from its second brim 13.2. In each vertical part 4, the second surface 12 is on the other side of the structure than the first surface 5. The shell part 13 is attached to the axle 1 from its ends. In the pulley 100 there are many metallic parts welding of which takes a lot of time and in several spots near the wings 2 there are spots that are difficult to weld. Sand and stone material leave the inside of the pulley because of the influence of gravity. The steel pulley is intensely worn due to the wearing effect of stones and sand.

In the publication US 4984363, there is presented a self-cleaning pulley where the ribs protrude radially out from the shell surface of the pulley which shell surface is inclined to the direction of the ends of the pulley. The removal slots of the material on the exterior perimeter of the pulley are of even width.

In publications US 2003/0173190 A1 and US 7527142, there are presented self- cleaning pulleys where the ribs are in v-shape. The leaving slots of the material to be removed on the exterior perimeter of the pulley are of even width.

In the publication US 3995487, there is presented a self-cleaning pulley where an elastomer layer is attached to a cylindrical steel shell which layer comprises longitudinal elastic ribs. The ribs protrude radially out from the tubular framework of the elastomer layer.

SUMMARY

According to a first aspect of the invention, a pulley for a conveyor is provided, which pulley comprises a shell surface to which cantilevers are attached for supporting the conveyor belt on the exterior perimeter of the pulley defined by the cantilevers. Two sequential cantilevers in the pulley are arranged such that the distance between said cantilevers increases from the middle of the pulley to the directions of both ends.

The distance between the cantilevers may increase in each radial distance from the rotating axle of the pulley in the middle of the pulley to the direction of both ends. According to a second aspect of the invention, a method for processing material with the pulley is provided, which pulley comprises a shell surface to which cantilevers are attached for supporting the conveyor belt on the exterior perimeter defined by the cantilevers, and in the method, the pulley is rotated in the rotating direction. In the method, material is transferred from the middle of the pulley to the direction of each ends of the pulley in a space defined between them by the shell surface, the conveyor belt and two sequential cantilevers, the distance between which increases from the middle of the pulley to the direction of each end.

According to a third aspect of the invention, an apparatus comprising a pulley according to any aspect or embodiment of the invention is provided.

The apparatus may comprise a crushing plant which may be fixed or mobile. The crushing plant preferably comprises a crusher. The apparatus may comprise a belt conveyor which preferably comprises a belt.

The cantilever may comprise vertical surfaces arranged to the direction of the rotation in a head first advancing v-shape, which vertical surfaces join from their upper brim to the orbicular surface arranged towards the belt.

The shell and the cantilever may be made of the same material.

The distance between the cantilevers may increase in the direction of the radius between the shell surface and the exterior perimeter.

The cantilever may comprise a wing. The wing may comprise a reinforcement which is arranged between the orbicular surface and the shell surface behind the vertical surface.

The reinforcement may comprise posterior vertical surfaces arranged in v-shape joining from their upper brim to the orbicular part comprising the orbicular surface arranged towards the belt and from their lower brim to the shell surface of the pulley, and the v-shaped posterior vertical surface is directed to the opposite direction of the rotation.

The cantilever may comprise a rib. The cantilever may be made of a plate by bending. The cantilever may be made of elastomer material such as rubber, polyethylene plastic or polyurethane, for instance cast polyurethane.

The cantilever structure of the pulley may comprise inclinations to multiple directions for removing material from between the pulley and the conveyor belt arranged to the pulley.

The thickness of the rib in the direction of the perimeter in a certain radial distance from the rotating axle may decrease from the middle of the pulley towards the end.

The thickness of the rib may decrease when moving further from the shell surface in the direction of the radius of the pulley.

When the distance between the cantilevers increases in the axial direction of the pulley from the middle of the pulley to the direction of each end, the moving of stones outward intensifies or at least the stones loosen more likely than when the distance between the cantilevers is constant. When the distance between the cantilevers increases in the axial direction outward from the middle, the area of the moving space of the stones increases.

The cantilever structure of self-cleaning pulley may be formed in a simple manner. According to some embodiments the wing of the pulley may be made of one part by folding. The wing may be plate-structured.

The cleaning capability of the pulley can be increased when the vertical surface of the structure protruding from the perimeter of the pulley is inclined in forwarding direction in respect of the rotating direction. When the pulley is rotating, the stones may leave the pulley when the wing or the vertical surface of the rib is inclined such that the stones move outward from inside the pulley in the direction of the radius. When the pulley is rotating the stones may leave the pulley when the wing or the vertical surface of the rib is inclined such that the stones move from the middle area of the pulley towards the ends of the pulley. An advantage of the forwarding inclined vertical surface is its capability to transfer material among others in the radial direction outward from inside the pulley during the rotation of the pulley or at least a capability to dislodge the stone material from the shell surface. When the leaving space or the leaving slot of the stone material between the wings or the ribs increases from inside of the pulley towards the ends, the stones do not lodge to the slot but are able to leave freely. The leaving slot or space of the stone material may increase in the axial direction of the pulley. The distance between cantilevers such as ribs for the leaving of the stone material may increase in the direction of the radius. The leaving slot of the stone material may increase in the axial direction of the pulley and in the direction of the radius of the pulley. A rib structure inclined in multiple direction enables an intensified leaving of material from between the belt and the pulley.

According to some embodiments, when the cantilevers ribs are arranged in v- shape, the contact of the belt with the cantilever may be levelled and thus the vibration caused by the contact in the conveyor may be decreased. A longer lasting contact of one cantilever with the belt decreases the vibration of the belt. A simultaneous contact of several cantilevers of the pulley with the belt decreases the vibration of the belt. The v-shape of the cantilevers intensifies the centralising the belt in the axial direction on a folding pulley.

According to some embodiments, when the inner shell surface of the exterior perimeter may be formed to a cylindrical hollow axle such as a tubular axle, the manufacturing of the pulley is simplified and sped up.

According to some embodiments, by changing the qualities of the rib material a desires wearing endurance of the pulley may be achieved. Preferably, the shell part of the pulley and the rib may be made of the same material when separate joints and joining are not needed. Other advantages can be found in the following description and claims. Aforementioned embodiments of the invention are described or have been described only with reference to one or more aspects of the invention. It will be evident to a person skilled in the art that any embodiment of any aspect can be applied in the same aspect and other aspects of the invention as such or in combination with other embodiments.

SHORT DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of example only with reference to the accompanying drawings with charts, in which:

Fig. 3 presents a first wing pulley as a perspective figure;

Fig. 4 presents from side a cylindrical axle of the pulley in Fig. 3, with one wing attached to the axle; Fig. 5 presents the wing of the pulley in Fig. 3 planar before bending;

Fig. 6 presents a cross-section of the pulley in Fig. 3 from the end of the pulley;

Fig. 7 presents a cross-section of the pulley in Fig. 3 from the middle of the pulley;

Fig. 8 presents a rib pulley as a perspective figure;

Fig. 9 presents a cross-section of the pulley in Fig. 8 from the end of the pulley; Fig. 10 presents a cross-section of the pulley in Fig. 8 in from the middle of the pulley;

Fig. 11 presents a second wing pulley as a perspective figure;

Fig. 12 presents the pulley in Fig. 11 from the end;

Fig. 13 presents the wing of the pulley in Fig. 11 as a perspective figure; Fig. 14 presents a reinforcement of the wing in Fig. 13 as a perspective figure; and

Fig. 15 presents a crushing plant which comprises a belt conveyor.

DETAILED DESCRIPTION

In the following description like references denote like parts. It shall be understood that the presented Figures are not in entirely to scale, and that they mostly serve to illustrate embodiments of the invention. The folding pulley 200 presented as a perspective figure in Fig. 3 comprises a rigid cylindrical shell 13 to which plate-structured wings 2 are attached. The wings 2 are of the width of the conveyor belt on the exterior perimeter of the pulley 200. The rotating direction of the pulley is shown with an arrow 15. Inside the shell 13 there may be a uniform axle fitted with a bearing to the both ends of the shell or the axle may be attached without rotating inside the shell or the pulley 200 may comprise a separate axle in both ends of the shell 13, which axle is fixed or fitted with a bearing in the end of the shell 13 (the axle is not presented in the Figs.).

There are wings 2 as a cantilever structure in the surface of the pulley 200, which wings are v-shaped in the rotation direction when viewed from their front part. The wings 2 are form of their shape as a v-type plough where the head is in the middle 200.1 of the pulley and during the rotation of the pulley steers the material being processed from the middle 200.1 of the pulley sideward to both ends 200.2 of the pulley and from the ends outside of the pulley 200. The wings 2 are stiffened from their upper brim. The stiffening has been implemented by plate-structure bendings which are preferably made regarding bending axles of different directions (bending spots 6.1 , 6.2 and 6.3). A sufficient amount of cantilevers are place on the surface of the pulley 200. The more capacity there is to place cantilevers 2 on the shell of the pulley the more steadily the belt moves over the pulley 200.

The wing 2 comprises a vertical part 4 which comprises a first surface 5 being foremost regarding the rotating direction 15 and an orbicular part 7 attached to the vertical part 4 through first bending radii 6.1 , which orbicular part is in an angular position regarding the vertical part 4. The first bending radii 6.1 on both sides of the middle point 200.1 of the wing 2 form a v-shape with each other. The spot of the bending radii 6.1 in the wing 2 is marked with a dotted line. The orbicular part 7 comprises a second bending radius 6.2 between the first bending radii 6.1 and the free brim 10 of the wing, the spot of the second bending radius in the wing 2 being marked with a double dotted line. The first bending radii 6.1 are situated symmetrically regarding the symmetry axle 1' of the pulley 200 in an angular position. The orbicular part 7 is planar between the first and the second bending radius. At least during the manufacturing there is a slot 20 presented in a dotted line in Fig. 3 in the middle point 200.1 in the wing 2. The orbicular part 7 of the wing 2 is bent in the middle point 200.1 in the spot of the bending radius 6.3 such that the diameter of the exterior perimeter 3 of the pulley may be greater in the middle 200.1 than in the ends 200.2. The slot 20 enables placing the vertical parts 4 of the wing 2 in v-shape in an angular position in the pulley 200.

The orbicular part 7 comprises a second surface 8 in contact with the conveyor belt, the second surface comprising a v-shaped anterior brim being first in contact with the belt in the rotation direction in the spot of the first bending radii 6.1. The second surface 8 continues as planar triangular areas until the second bending radius 6.2 after which the second surface 8 ends in the free brim 10.

The second surfaces 8 of the wings 2 form the intermittent circular exterior perimeter 3 of the pulley 200. The stones and sand may leave the pulley through slots defined by adjacent wings 2, the shell surface 14 of the shell 13 and the belt on the pulley 200.

The vertical part 4 of each wing is attached to the shell surface 14 from its interior brims 4' by welding such that the first surfaces 5 of the vertical part 4 and the radius of the pulley 200 form an angle between them. The vertical part 4 is formed of two parts 4.1 and 4.2 divided by the slot 20 and when desired, possibly attached to each other, and the parts are mirrors of each other.

The shell part 13 comprises an exterior shell surface 14. Inside the pulley i.e. between the wings 2, a stone moves sloWly on the shell surface 14 and/or along the inclined first surfaces 5 of the vertical parts 4 from the middle 200.1 of the pulley to the direction of the ends 200.2. The shell part 13 is preferably hollow. The shell part 13 is preferably formed of a tube.

Fig. 4 presents from side the cylindrical shell part 13 of the pulley 200 in Fig. 3 to which one wing 2 is attached. Fig. 5 presents the wing 2 of the pulley 200 planar before bending from the first radii 6.1 , the second bending radius 6.2 and the third bending radius 6.3. Bevels 17 are made to the joining point of the end surfaces 16 of the wing and the interior brim 4' of the vertical part 4 by removing triangular pieces of plate.

Fig. 6 presents a cross-section of the pulley 200 from the end of the pulley and Fig. 7 presents a cross-section of the pulley 200 from the middle of the pulley. With Figs. 6 and 7 it can be clearly seen that in the pulley 200, the size of the slots 9 defined by adjacent wings 2, the shell surface 14 of the shell 13 and the belt on the pulley 200 increases when moving from the middle 200.1 of the pulley to the direction of the ends 200.2 of the pulley. Thus the departure of stones becomes more effective. In Fig. 6, there is presented distance 9.2 which for sequential wings 2 is in the middle 200.1 of the pulley. In the example, the distance between two wings 2 in the end 9.2 is greater than the distance 9.1 in the middle.

The folding pulley 201 presented in Fig. 8 as a perspective figure comprises a cylindrical shell 23 to which plate-structured ribs 22 are attached. The ribs are preferably formed of elastomer material such as rubber or polyethylene plastic or polyurethane or corresponding material enduring wearing of rough and fine material, for instance stone substance. The ribs 22 are of the width of the conveyor belt on the exterior perimeter of the pulley 201. The circling direction of the pulley 201 is presented with an arrow 15. Inside the shell 23 there may be a uniform axle fitted with a bearing to the both ends of the shell or the axle may be attached without rotating inside the shell or the pulley 201 may comprise a separate axle in both ends of the shell 23, which axle is fixed or fitted with a bearing in the end of the shell 23.

A rigid tubular axle 21 arranged inside the shell 23 is presented in Fig. 8. When the axle 21 is rigid the shell 23 does not need to carry all the load of the pulley. The rotating axle of the pulley is marked 21 '.

The shell 23 is preferably formed of the same material as the ribs 22. When the ribs 22 and the shell 23 are of elastomer material, they may be made of several pieces by joining them together and attached without rotating around the rigid axle 21. In the example in Fig. 8, the shell 23 is made of four pieces cylindrical of their exterior surface, which are attached to each other with the axle 21 such that the exterior surface 24 of the shell 23 forms an inclined uniform shell surface 24 from the middle 201.1 of the pulley to the ends 201.2 of the pulley.

V-shaped ribs 22 are attached to or formed in the manufacturing phase for cantilever structure to the shell surface 24 of the pulley 201. Ribs 22 are formed in a form of a v-type plough the head of which is in the middle 201.1 of the pulley and the rib 22 in the form of a v-type plough guides the material being processed during the rotation of the pulley from the middle 201.1 of the pulley to both ends 201.2 of the pulley and from the ends outside the pulley 201. The ribs 22 may be stiffened from their upper brim. The stiffening may be implemented for instance with a possibly v-shaped stiffener arranged inside the rib 22. A sufficient amount of cantilevers 22 are place on the surface of the pulley 201. The more capacity there is to place cantilevers 22 on the shell of the pulley the more steadily the belt moves over the pulley 201.

The rib 22 comprises a first surface 25 being foremost regarding the rotating direction 15 and a posterior second surface 26, which surfaces join the orbicular surface 27 of the rib 22 with their exterior brims placed on the perimeter of the pulley. The orbicular surfaces 27 form the contact surface of the pulley 201 to the belt. According to some embodiments the orbicular surface 27 forms a right angle with the first 25 and the second 26 surface. Preferably, the thickness of the rib in the orbicular direction is greater in the middle 201.1 of the pulley 201 than in the end 201.2 of the pulley. Preferably, the thickness of the rib 22 in a certain radial distance of the rotating axle 21' decreases from the middle 201.1 of the pulley towards the end 201.2 of the pulley. Preferably, the thickness of the rib 22 may decrease when moving further from the shell surface 24 in the direction of the radius.

The second orbicular surfaces 27 of the ribs 22 for an intermittent circular exterior perimeter of the pulley 201. Stones and sand may leave the pulley 201 through slots 9 defined by adjacent ribs 22, the shell surface 24 of the shell 23 and the belt on the pulley 201.

The shell part 23 comprises the cylindrical shell surface arranged with a diameter decreasing from the middle 201.1 of the pulley to the ends 201.2. Inside the pulley

201 i.e. between the ribs 22 a stone moves on the shell surface 24 and/or guided by the vertical first surface 25 and/or second surface 26 from the middle 201.1 of the pulley to the direction of the ends 201.2.

Fig. 9 present a cross-section of the pulley from the end of the pulley and Fig. 10 presents a cross-section of the pulley 201 from the middle of the pulley. With Figs. 9 and 10 it can be clearly seen that in the pulley 201 , the size (cross-section area) of the slots 9 defined by adjacent ribs 22, the shell surface 24 of the shell 23 and the belt on the pulley 201 or of the leaving spaces 9 increases when moving from the middle 201.1 of the pulley to the direction of the ends 201.2 of the pulley. Thus the leaving of stones becomes more effective. The distance 9.2 which for adjacent ribs 22 is in the end 201.2 of the pulley is presented in Fig. 9. The distance 9.1 which for adjacent ribs 22 is in the end 201.1 of the pulley is presented in Fig. 10. In the example the distance between two ribs 22 is greater in the end 9.2 than in the middle 9.1.

A second wing pulley 202 is described with Figs. 11. The wing 2 of the wing pulley

202 differs from the wing of the type of wing pulley 200 described with Figs. 3-7 such that the wing 2 also comprises a reinforcement 18 which is arrange between the orbicular surface 8 of the wing and the shell surface 14 of the pulley 202 behind the vertical surface 5. The orbicular part 7 of the wing 2 may be supported with the reinforcement 18 for instance such that the orbicular part 7 becomes more rigid in the direction of the radius of the pulley.

The reinforcement 18 comprises posterior vertical surfaces 19.1 , 19.2 arranged in v-shape joining from their upper brim to the orbicular part 7 comprising the orbicular surface 8 arranged towards the belt and from their lower brim to the shell surface 14 of the pulley 202. Preferably, the reinforcement comprises a plate which is bent in the middle 202.1 of the pulley. The ends of the reinforcement 18 are attached to the posterior surface 12 of the vertical part 4. The v-shaped posterior vertical surface 19 formed uniform is focused in the opposite direction 15' regarding the direction of the rotation 15 of the pulley 202. The pulley 202 has been formed by the wings 2 equipped with the reinforcement 18, in which pulley two sequential wings are arranged such that the distance between said wings increases from the middle 202.1 of the pulley to the direction of both ends 202.2.

Fig. 12 presents the pulley in Fig. 11 from the direction of the end 202.2. Fig. 13 presents the wing 2 of the pulley in Fig. 11 shown from below the wing such that the empty space between the vertical part 4 and the reinforcement is seen. Preferably, the reinforcement 18 is welded to the other parts of the wing before joining the wing to the shell surface 14 for instance by welding. Fig. 14 presents the reinforcement 18 of the wing in Fig. 13 before joining it to the wing 2.

The wing 2 may be formed of a uniform piece which may be enclosed or which does not have a hollow structure but which has the preferred appearances of the wing described by Figs. 11-14.

In Fig. 15, there is presented a processing apparatus of mineral material, a crushing plant 300 where there is a feeder 303 for feeding material to a crusher 304 and a belt conveyor 306 for transferring crushed product further from the crushing plant.

The belt conveyor 306 presented in the figure comprises a belt 307 which is arranged to move around at least one pulley 200, 201 , 202. The pulley 200, 201 , 202 according to different embodiments of the invention may also be used in connection with a different type of crusher such as a gyratory, cone or centrifugal crusher. The crushing plant 300 also comprises a power source and a control centre 305. The power source may be for instance a diesel or electronic motor which provides energy for the use of process units and hydraulic circuits.

The feeder, crusher, power source and conveyor are attached to the framework 301 which in this embodiment also comprises a roll platform 302 for moving the crushing plant. The crushing plant may also be with totally or partly wheel platform or movable on legs. Alternatively, it may be movable/trailable for instance by a trailer lorry or some other exterior power source.

Mineral material may be for instance mined stone or it may be demolition waste of a building, such as cement, tiles etc. In addition to the aforementioned, the crushing plant may be a fixed crushing plant.

The foregoing description provides non-restricting examples of some embodiments of the invention. It is clear to a person skilled in the art that the invention is not restricted to the presented details but that the invention can be implemented in other equivalent means.

Some of the features of the presented embodiments may be used to advantage without the corresponding use of other features. As such, the foregoing description shall be considered as merely illustrative of the present invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.

Claims

1. A pulley (200,201 ,202) for a conveyor, comprising a rotatable shell (13,23) to a shell surface (14,24) of which cantilevers (2,22) are attached for supporting a conveyor belt (307) on an exterior perimeter (3) defined by orbicular surfaces (8,27) comprised by the cantilevers (2,22), characterised by arranging two sequential cantilevers (2,22) in the pulley (200,201 ,202) such that the distance (9.1 ,9.2) between said cantilevers increases from the middle (200.1 ,201.1 ,202.1 ) of the pulley to the direction of both ends (200.2,201.2,202.2).

2. A pulley according to claim 1 , characterised in that the cantilever (2,22) comprises vertical surfaces (5,25) arranged to the direction of the rotation (15) in a head first advancing v-shape, which vertical surfaces join from their upper brim to the orbicular surface (8,27) arranged towards the belt (307).

3. A pulley according to claim 1 or 2, characterised in that the shell (13,23) and the cantilever (2,22) are made of same material.

4. A pulley according to claims 1 to 3, characterised in that the distance between the cantilevers (2,22) increases in the direction of a radius between the shell surface (14,24) and the exterior perimeter (3).

5. A pulley according to any of claims 1 to 4, characterised in that the cantilever (2) comprises a wing.

6. A pulley according to claim 5, characterised in that the wing (2) comprises a reinforcement (18), which is arranged behind the vertical surface (5) between the orbicular surface (8) and the shell surface (14).

7. A pulley according to claim 6, characterised in that the reinforcement (18) comprises posterior vertical surfaces (19.1 ,19.2) arranged in v-shape, which surfaces join from their upper brim to the orbicular part (7) comprising the orbicular surface (8) arranged towards the belt (307) and from their lower brim to the shell surface (14) of the pulley (202), and the v-shaped posterior vertical surface (19) is directed to the opposite direction (15') of the rotation (15).

8. A pulley according to any one of claims 1 to 5, characterised in that the cantilever (22) comprises a rib.

9. A pulley according to any one of claims 1 to 8, characterised in that the cantilever (2,22) is made of plate, preferably by bending.

10. A pulley according to any one of claims 1 to 9, characterised in that the cantilever (2,22) is made of elastomer material such as rubber, polyethylene plastic or polyurethane.

11. A pulley according to any one of claims 1 to 10, characterised in that the cantilever structure (2,22) comprises inclinations to several directions for removing material from between the pulley (200,201 ) and the conveyor belt (307) arranged onto the pulley.

12. A pulley according to any one of claims 1 to 11 , characterised in that the thickness of the cantilever (2,22) in a certain radial distance from a rotating axle

(21 ') decreases from the middle (201.1 ) of the pulley towards the end (201.2).

13. A pulley according to any one of claims 1 to 12, characterised in that the thickness of the rib (22) decreases when moving further from the shell surface (24) in the direction of the radius of the pulley.

14. An apparatus comprising a pulley (200,201 ,202) according to any one of claims 1 to 13.

15. An apparatus according to claim 14 comprising a crushing plant (300), comprising a crusher (304).

16. An apparatus according claim 14 or 15 comprising a belt conveyor (306), comprising a belt (307).

17. A method for processing material with a pulley (200,201 ,202) comprising a shell surface (14) to which cantilevers (2,22) are attached for supporting a conveyor belt (307) on an exterior perimeter (3) of the pulley, defined by the cantilevers, and in the method, the pulley is rotated in a rotating direction (15), characterised in that in the method, material is transferred from the middle

(200.1.201.1.202.1 ) of the pulley (200,201 ,202) to the direction of both ends

(2.0.2.201.2,202.2) of the pulley in a space (9) defined between them by the shell surface (14), the conveyor belt (307) and two sequential cantilevers (2,22), the distance (9.1 ,9.2) between which increases from the middle of the pulley to the direction of each end.