EP1874664A1

EP1874664A1 - Arrangement for running conveyor belt of belt conveyor

Info

Publication number: EP1874664A1
Application number: EP06725940A
Authority: EP
Inventors: Jukka Pajuranta
Original assignee: Sandvik Mining and Construction Oy
Current assignee: Sandvik Mining and Construction Oy
Priority date: 2005-04-28
Filing date: 2006-04-26
Publication date: 2008-01-09
Also published as: AU2006239144A1; CN101171191A; KR20080011174A; WO2006114481A1; FI20055201A; FI118992B; ZA200709130B; FI20055201A0; RU2007144102A; EP1874664A4

Abstract

The invention relates to a method for running a conveyor belt of a belt conveyor, a belt conveyor, and a guide element of a conveyor belt. The transport section of the belt conveyor (6) has a bend (16), in which the conveyor belt (10) runs upward along a curved path. At the bend, the belt edges are supported with elongated belt guides (23) that are stationary with respect to the belt. The belt guides have a curved sliding surface (26) that is arranged against the outer surface (10a) of the belt.

Description

ARRANGEMENT FOR RUNNING CONVEYOR BELT OF BELT CONVEYOR

BACKGROUND OF THE INVENTION

[0001] The invention relates to a method for running a conveyor belt in a belt conveyor, the method comprising: running a conveyor belt in the shape of a closed loop around at least two pulley drums; transferring on a moving top surface of the conveyor belt that serves as a transport section material from a feed station to a discharge station of the belt conveyor; transferring on a bottom return section of the belt conveyor the conveyor belt back to the feed station; running in the transport section the conveyor belt into at least one bend, in which the conveyor belt runs upward along an ascending curved path as seen in the transport direction; supporting the bottom surface of the conveyor belt with several support rolls in the transport section; arranging at least two support elements at the bend in the transport section; and supporting with the support elements the outer surface of the conveyor belt in the areas of the opposite edges of the conveyor belt.

[0002] The invention further relates to a belt conveyor comprising: at least two pulley drums; a conveyor belt that is in the shape of a closed loop and arranged to be run around the pulley drums; a first conveyor section and a second conveyor section that are at an angle to each other; at least one bend in the transport section of the belt conveyor between said conveyor sections and at the bend, the conveyor belt is arranged to run upward along an ascending curved path as seen in the transport direction; and at least two support elements on the opposite edge sections of the conveyor belt and arranged against the outer surface of the conveyor belt at said bend.

[0003] The invention yet further relates to a guide element of a conveyor belt comprising at least one support element that is arrangeable against the outer surface of the conveyor belt in the transport section of the belt conveyor.

[0004] In certain situations a belt conveyor is needed with two conveyor sections arranged at an angle to each other. In such a conveyor the conveyor belt does not run linearly on the section between the pulley drums, but makes a bend upward as seen in the direction of travel. The problem then is that, at the bend, the belt does not run on the support rolls below the belt, but rises upward, i.e. tries to straighten the bend. Attempts have been made to solve this problem by arranging idlers at the belt, which press the belt edge against the support rolls from the outer surface side of the belt. However, this has created a new problem, namely that the idlers have to be relatively wide and thus form a narrowing at the bend, through which the material on the belt needs to push. Another problem with the idlers is that they easily collect dirt, and long particles twist around them, whereby the idlers may stop turning and possibly damage. Therefore, the idlers need to be encased to prevent impurities from entering their structures. Unfortunately, casings surrounding the idlers narrow the free width of the conveyor even further at the bend. Thus, the transport capacity of the present belt conveyors equipped with idlers is significantly limited by the narrowing at the bend.

BRIEF DESCRIPTION OF THE INVENTION

[0005] The object of this invention is to provide a novel and improved method for running a conveyor belt in a belt conveyor, a belt conveyor, and a guide element of a conveyor belt.

[0006] The method of the invention is characterised by supporting the opposite edges of the conveyor belt at a bend by means of at least two elongated belt guides, and directing the edges of the conveyor belt to go between a support roll and a substantially stationary sliding surface on the bottom surface of the belt guide.

[0007] The belt conveyor of the invention is characterised in that it comprises at least two guide elements that are arranged substantially stationary with respect to the conveyor belt, and that the guide element comprises at least one elongated belt guide with a curved sliding surface arranged against the outer surface of the conveyor belt.

[0008] The guide element of the invention is characterised in that it comprises at least one elongated belt guide, and that the belt guide has a sliding surface that is substantially stationary with respect to the conveyor belt and arrangeable against the outer surface of the belt.

[0009] The idea of the invention is that guide elements are arranged on the opposite edges of the belt to support the belt at the bend in the transport section. The guide element has an elongated belt guide with a sliding surface on its bottom surface, which can be arranged against the outer surface of the belt. The belt then runs between the sliding surface of the belt guide and the support rolls below the belt. [0010] The invention provides the advantage that the belt guides can be designed to be narrow components in the cross-direction, in which case they require clearly less space in the edge area of the conveyor belt than the presently used idlers. In addition, the belt guides do not necessarily need to be encased, which further makes it possible to have a greater free width between the support elements. Thus, the conveyor does not have a point of discontinuity in the material flow at the bend. Another advantage is that the construction of the belt guide is simple, whereby it may be inexpensive in price. Because there are no moving parts between the conveyor belt and guide element, the structure of the guide element of the invention is strong and needs little maintenance.

[0011] An idea of an embodiment of the invention is that two or more belt guides are arranged one after the other in the longitudinal direction at a distance from each other. The conveyor belt can then be supported over a relatively long section at the bend. In addition, consecutive belt guides in the transport direction can be arranged on both sides of a turning link between the conveyor sections.

[0012] An idea of an embodiment of the invention is that the conveyor sections are at a fixed angle to each other and that on the edge of the belt, one relatively long belt guide or several consecutive belt guides are arranged in such a manner that the guide element covers the entire bend as a substantially uniform structure.

[0013] An idea of an embodiment of the invention is that the guide element comprises control elements to adjust the position of the belt guide in relation to the conveyor belt. At their simplest, the control elements comprise manual means, such as a screw or eccentric mechanism, for positioning the belt guide and locking it in place. Alternatively, the control elements may comprise one or more actuators for moving and locking the belt guide. An automatic device may have a control unit to control the operation of the control element on the basis of information received from one or more sensors.

[0014] An idea of an embodiment of the invention is that the belt guide comprises a sliding surface made of a plastic material and arranged to be set against the outer surface of the conveyor belt. The sliding surface may be of polyamide (PA), polytetrafluoroethylene (PTFE), polyethylene (PE- UHIvIW), or some other wear-resistant material suitable for sliding elements. [0015] An idea of an embodiment of the invention is that the belt guide comprises a detachable sliding element that can be replaced when necessary. Further, the sliding element may have a curved sliding surface made during manufacturing, or alternatively the sliding element may be made of a flexible material and bent against the curved mounting face of the belt guide during installation.

[0016] An idea of an embodiment of the invention is that the belt guide has a curved sliding surface that is coated with a plastic material.

[0017] An idea of an embodiment of the invention is that the edges of the conveyor have side rims and the belt guides are arranged outside the side rim structure. The belt guides are then protected from dirt.

BRIEF DESCRIPTION OF THE FIGURES

[0018] Some embodiments of the invention will be described in more detail in the attached drawings, in which

Figure 1 is a schematic view of a waste treatment device to which the belt conveyor of the invention can be applied,

Figure 2 is a schematic side view of a belt conveyor with an ascending bend in the transport direction of the belt,

Figure 3 is a top view of a known solution for directing the conveyor belt on the bend section,

Figure 4 is a schematic side view of a section of a belt conveyor of the invention,

Figure 5 is a schematic top view of an inventive method of supporting the conveyor belt at the bend, and

Figure 6 is a partly cross-sectional view of a guide element of the invention in the longitudinal direction of the conveyor.

[0019] In the figures, some embodiments of the invention are shown simplified for the sake of clarity. Similar parts are marked with the same reference numbers in the figures.

DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE INVENTION

[0020] Figure 1 shows a waste crusher 1 that processes waste for further use. The waste crusher 1 can be arranged on a moving carrier 2, such as a trailer. Waste 4 can be fed into the feed opening 3 of the waste crusher 1 , from which it is then led between crushing elements 5 where the waste 4 is chopped and then drops to a belt conveyor 6 connected to the waste crusher 1 , which transports the processed waste 4 to a storage location 7. The frame of the belt conveyor 6 can comprise a sliding mechanism or the like so that the conveyor 6 can easily and quickly be pushed in its place on the carrier 2, and, on the other hand, the conveyor 6 can easily and quickly be pulled off the carrier 2 for maintenance and repairs, for instance. The belt conveyor 6 may comprise at least a first section 6a and a second section 6b. The first section 6a of the conveyor is essentially horizontal and arranged on the carrier 2 in such a manner that processed waste 4 or other material may fall on its transport section, i.e. moving top surface. The second section 6b of the conveyor is, in turn, outside the waste crusher 1 and may be arranged in an angular position A with respect to the first conveyor section 6a. The transport section, i.e. moving top surface, of the second conveyor section 6b moves the processed waste 4 horizontally to a distance from the waste crusher 1 , and at the same time, it moves the waste vertically up so that the processed waste 4 can fail off the discharge end 8 of the belt conveyor 6 and form a pile 9. This way, it is possible to form a relatively high pile 9 of the waste 4, which reduces the need to move the waste crusher 1. So that the structure of the belt conveyor 6 was as simple as possible and that it took as little space as possible, a mobile solution should, instead of several separate conveyors, use a belt conveyor 6 in which one conveyor belt 10 is run as one uniform endless structure around pulley drums 11 and 12. Typically, one of the pulley drums is a driver pulley that transmits moving force to the conveyor belt. The pulley drum that does not transmit moving force to the belt is usually called a return pulley. Further, the conveyor 6 may also have one or more turning devices 13 to turn the second conveyor section 6b to a desired angular position A with respect to the first conveyor section 6a. The turning may occur around a turning link 14. The turning device 13 can be a mechanical device or a pressure medium-operated actuator, such as a hydraulic cylinder. Further, the conveyor 6 may have one or more second turning links 15, in which case the conveyor 6 can be turned into a transport position that requires only a little space in the longitudinal direction.

[0021] Figure 2 shows the bend 16 between the first 6a and second 6b sections of the belt conveyor 6, in which the top section, i.e. transport section, of the conveyor belt 10 curves upward when the belt 10 is run in its normal direction of travel B. At the bend 16, the outer surface 10a of the conveyor belt 10, i.e. the surface against the material being transported, forms a curved inner surface. On the return section, i.e. the bottom section of the conveyor belt 10, the belt runs in the return direction C, and its outer surface 10a forms a curved outer surface at the bend 16. On the transport section, several support rolls 17 support the belt 10 on its inner surface 10b side. Correspondingly, on the return section, the support rolls 17 support the belt 10 on its outer surface 10a side. If the belt 10 is not supported on the outer surface 10a side of the transport section at the bend 16, it tends to detach from the surface of the support rolls 17 and to straighten the bend 16. As illustrated in Figure 2, the belt 10 tries to move on the transport section in the direction of the arrows to the position shown by dashed line 18. On the return section, there may be a transverse support roll 19 at the bend on the inner surface 10b side of the conveyor belt 10 to prevent the return section of the belt 10 to straighten at the bend 16.

[0022] Figure 3 shows a known solution for supporting the transport section of the conveyor belt 10 on the outer surface 10a thereof so that the belt 10 runs along a designed curved path at the bend 16. Idlers 20 on the outer surface 10a side press the outer edges of the conveyor belt. So that the idlers 20 would not collect the material being transported on the belt 10 into their structures, they are protected by casings 21. The protective casings 21 direct the material transported on the conveyor belt 10 past the idlers 20. However, at the same time, the idlers 20 and protective casings 21 form a significant narrowing to the material flow on the belt. The entire width L1 of the conveyor belt 10 can then not be utilised, and the transport capacity must be designed according to the smallest free width of the conveyor 6, i.e. according to the width L2 of the narrowing at the bend 16. Even if the capacity was dimensioned correctly, the strong narrowing would cause a point of discontinuity in the material flow, and consequently, the conveyor would be susceptible to malfunctions, such as blockage.

[0023] Figure 4 shows a solution of the invention for supporting the transport section of the conveyor belt 10 on the outer surface 10a side of the belt with guide elements 22. In this case, two guide elements 22a, 22b are arranged one after the other on both edges of the belt 10. The guide elements 22a, 22b may be at a distance from each other so that the turning link 14 is between them. The guide element 22 may comprise an elongated belt guide 23 that may be supported by means of one or more supports 24 to the frame 25 of the conveyor. The support 24 may have control elements to adjust the position of the belt guide 23 in relation to the belt 10. The belt guide 23 may have a sliding surface 26 that may be curved and arranged with the control elements against the outer surface 10a of the belt so that the belt 10 is supported between the support roll 17 and sliding surface 26. The sliding surface 26 may be a fixed part of the belt guide 23. Thus, the sliding surface 26 may for instance be moulded as part of the belt guide 23, or the belt 10 side surface of the belt guide 23 may be coated with a suitable sliding material, such as a suitable plastic material. Alternatively, the sliding surface may be a separate replaceable wear element 27 made of polyamide or polytetrafluoroethylene, for instance.

[0024] For the sake of clarity, Figures 1 , 2, and 4 do not show side rims on the edges of the conveyor 6, which prevent the material being transported from falling cross-wise off the transport section.

[0025] It should be noted that the length of the belt guide 23 may be designed nearly equal to the distance between the support rolls 17 against the inner surface 10b of the belt on the transport section, or larger.

[0026] Figure 5 shows that a required number of guide elements 22a to 22d may be arranged against the outer surface 10a of the belt 10. The guide elements 22 may be arranged on the opposite edges of the belt 10 so that the outermost section of the belt 10 remains between the guide element 22 and support roll 17, as clearly shown in Figure 6. Because the structure of the guide elements 22 is narrow in cross-direction, and because the guide elements 22 are arranged at the very edge of the belt 10, a width L3 remains between the guide elements 22a, 22c and 22b, 22d, respectively, on the opposite edges of the belt 10, which is significantly larger than the free width L2 of the known solutions.

[0027] Figure 6 shows a possible construction of the guide element 22. The guide element 22 comprises a belt guide 23 that has a replaceable sliding element 27 attached to its bottom surface, and the sliding element has on its bottom surface a sliding surface 26 arrangeable against the outer surface 10a of the belt 10. A support 24 supports the belt guide 23 to the frame 25 of the conveyor. The support 24 also has control elements 28 with which it can be adjusted in direction E in relation to the belt 10. Further, it is possible to arrange means to the support 24 to adjust the belt guide 23 in the cross-direction F of the belt 10. The control elements 28 may comprise a mechanical control component, such as a screw or eccentric, or alternatively, the adjustment can be made with an actuator. [0028] It is also possible to have one or more side guide elements 29 on both sides of the belt 10 at the bend 16. The side guide element 29 may be connected to the guide element 22, for instance, or it may be fastened to the frame 25 of the conveyor. If the conveyor belt 10 tries to move to the edge of the conveyor for some reason, the side guide element 29 restricts this movement. Then the edge of the conveyor belt 10 does not rub against the structures of the conveyor 6 and damage. In addition, the side guide elements 29 prevent the edges of the belt 10 from moving away from below the belt guides 23, and consequently, the guide elements 22 always support the belt on both edge sat the bend 16. The side guide element 29 may be an elongated element that may comprise a replaceable sliding element 30 made of a suitable wear-resistant plastic material. There may be several consecutive side guide elements 29 at the bend in the transport direction B. Further, the side guide element 29 may be integrated to the belt guide 23 or sliding element 27, as shown in Figure 6 by dashed line 32.

[0029] Supporting the belt 10 on the edges to a curved path with the elongated belt guides 23 over a relatively long way prevents the bending of the midsection of the belt 10 at the bend 16. In addition, when at the bend 16, the belt 10 curves and is, thus, also stiffer than before at the midsection. Further, because the side guide elements 29 control the movement of the belt 10 to the side, the belt 10 is all the time supported at the bend 16.

[0030] As Figure 6 shows, the guide element 22 may be arranged outside the side rims 31 of the belt conveyor 6, whereby the guide element 22 is well protected from the effects of the material being transported.

[0031] Two or more consecutively arranged belt guides 23 may be connected to each other by a link. The ϋnk allows the belt guides 23 to move with respect to each other if the conveyor sections 6a, 6b are turned with respect to each other.

[0032] In some cases, the features presented in this application can be used as such regardless of the other features. The features presented in this application can also be combined as necessary to form various combinations.

[0033] The drawings and the related description are only intended to illustrate the idea of the invention. The invention may vary in detail within the scope of the claims.

Claims

1. A method for running a conveyor belt in a belt conveyor, the method comprising: running a conveyor belt (10) in the shape of a closed loop around at least two pulley drums (11, 12); transferring on a moving top surface of the conveyor belt (10) that serves as a transport section material from a feed station to a discharge station of the belt conveyor (6) in the transport direction (B); transferring on a bottom return section of the belt conveyor (6) the conveyor belt (10) back to the feed station; running in the transport section the conveyor belt (10) into at least one bend (16), in which the conveyor belt (10) runs upward along an ascending curved path as seen in the transport direction (B); supporting the bottom surface (10b) of the conveyor belt (10) with several support rolls (17) in the transport section; arranging at least two support elements at the bend (16) in the transport section; and supporting with the support elements the outer surface (10a) of the conveyor belt (10) in the areas of the opposite edges of the conveyor belt (10), characterised by supporting the opposite edges of the conveyor belt (10) at the bend (16) by means of at least two elongated belt guides (23); and directing the edges of the conveyor belt (10) to go between a support roll (17) and a substantially stationary sliding surface (26) on the bottom surface of the belt guide (23).

2. A method as claimed in claim ^characterised by supporting the edges of the conveyor belt (10) at the bend (16) by means of at least two consecutive belt guides (23) in the transport direction (B).

3. A method as claimed in claim 1 or 2, characterised by adjusting the distance between the belt guide (23) and the outer surface (10a) of the conveyor belt (10) with at least one control element (28).

4. A belt conveyor comprising: at least two pulley drums (11, 12); a conveyor belt (10) that is in the shape of a closed loop and arranged to be run around the pulley drums (11 , 12); a first conveyor section (6a) and a second conveyor section (6b) that are at an angle (A) to each other; at least one bend (16) in the transport section of the belt conveyor (6) between said conveyor sections (6a, 6b), and at the bend (16), the conveyor belt (10) is arranged to run upward along an ascending curved path as seen in the transport direction (B); and at least two support elements on the opposite edge sections of the conveyor belt (10) and arranged against the outer surface (10a) of the conveyor belt at said bend (16), c h a r a c t e r i s e d in that the belt conveyor (6) comprises at least two guide elements (22) that are arranged substantially stationary with respect to the conveyor belt (10); and the guide element (22) comprises at least one elongated belt guide (23) with a curved sliding surface (26) arranged against the outer surface (10a) of the conveyor belt.

5. A belt conveyor as claimed in claim 4, c h a r a c t e r i s e d in that at the bend (16), there are at least two consecutive belt guides (23) in the transport direction (B), the first belt guide (23a, 23c) being on the first conveyor section (6a) and the second belt guide (23b, 23d) being on the second conveyor section (6b).

6. A belt conveyor as claimed in claim 4 or 5, c h a r a c t e r i s e d in that the belt conveyor (6) is arranged to a crusher (1 ) equipped with a moving carrier (2); the first conveyor section (6a) comprises quick clamping means for arranging the conveyor (6) detachably on the carrier (2); there is a turning link (14) between the first conveyor section (6a) and second conveyor section (6b); and the second conveyor section (6b) is turnable with a turning device (13) with respect to the substantially horizontal first conveyor section (6a).

7. A guide element of a conveyor belt comprising at least one support element that is arrangeable against the outer surface (10a) of the conveyor belt (10) in the transport section of the belt conveyor (6), characterised in that the guide element (22) comprises at least one elongated belt guide (23); and the belt guide (23) has a sliding surface (26) that is substantially stationary with respect to the conveyor belt (10) and arrangeable against the outer surface (10a) of the belt.

8. A guide element as claimed in claim 7, characterised in that a separate sliding element (27) is fastened to the belt guide (23), and its bottom surface forms a curved sliding surface (26).

9. A guide element as claimed in claims 7 or 8, characterised in that the sliding surface (26) is made of a plastic material.

10. A guide element as claimed in any one of the preceding claims 7 to 9, characterised in that the guide element (22) comprises at least one control element (28) to adjust the position of the belt guide (23) in relation to the conveyor belt (10).

11. A guide element as claimed in any one of the preceding claims 7 to 9, characterised in that there is at least one side guide element (29) connected to the guide element (22) for restricting the transverse movement of the conveyor belt (10).