EP2297007A1

EP2297007A1 - Belt conveyor

Info

Publication number: EP2297007A1
Application number: EP09788212A
Authority: EP
Inventors: Lodewijk Stephanus Magaretha Joseph Van Der Borg
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-07-07
Filing date: 2009-07-07
Publication date: 2011-03-23
Also published as: NL2001774C2; RU2011104086A; WO2010005300A1; RU2533776C2

Abstract

Belt conveyor (1), particularly for a helical conveyor, comprising a conveyor belt extending along a conveyance path, comprising a series of elongated support members or links (4) for supporting goods to be conveyed, which links extend transverse to the belt, and a series of connecting rods (20) for connecting the links one to the other, wherein a number of first links each comprise a drive body (131) of a magnetic material, and a drive mechanism (100) comprising one or more magnets placed along the conveyor belt for generating a magnetic field for exerting a driving force on one or more of the drive bodies near the magnets, and wherein the drive mechanism is placed in a bend.

Description

Belt conveyor

BACKGROUND OF THE INVENTION

The invention relates to a conveyor, particularly to a conveyor belt adapted for traversing bends in the horizontal and the vertical plane and for instance having an open supporting structure.

Such conveyor belts are predominantly used in the food industry, particularly in so-called helical towers, for cooling or heating, rising (proving) etc., in which the conveyor belt traverses a helical path, engaged at the inside for driving.

Said conveyor belts, below called link belt, among others have to be easy to clean, and to that end often have an open structure. They have been built up from elongated, transversely oriented synthetic support members or links, having a kind of zig-zag shape, which in the direction of the conveyor belt extend into each other, and are connected there by means of connecting rods.

Such link belts are for instance used in a helical conveyor for during a certain period of time under conditioned circumstances having products circulate, particularly food products, such as dough products. Such a helical conveyor comprises a framework for supporting a helical path having a number of windings or storeys placed above one another, a link belt resting on the helical path and able to move along it. Within the helical path a rotatable drum is positioned against which the side of the link belt facing the drum abuts for driving the link belt using friction. The peripheral velocity of the drum is slightly higher than the speed of locomotion of the link belt. Slight slippage will therefore occur. The conveyors in question however, are exposed to temperature changes and sometimes the products will soil as well. The friction coefficient between the drum and the link belt can as a result acquire a different value which may give rise to problems.

The known helical conveyor is furthermore provided with a rotatable drum, in the shape of a stainless steel pipe. Said pipe forms a costly element of the helical conveyor and, in view of the dimensions of the known helical conveyors, has large dimensions which may give rise to problems when transporting or building up the helical conveyor.

It is an object of the invention to provide a conveyor of the above- mentioned type, that needs to be maintained/repaired less often.

It is a further object of the invention to provide a conveyor of the above-mentioned type, wherein wear of the conveyor belt is reduced or can even be avoided.

SUMMARY OF THE INVENTION

In order to at least achieve one of these objects the invention provides, according to one aspect, a belt conveyor comprising a conveyor belt extending along a conveyance path, comprising a series of elongated support members or links for supporting goods to be conveyed, which links extend transverse to the belt, and a series of connecting rods for connecting the links one. to the other, wherein the series of links comprises a number of drive links that each comprise a drive body of a magnetic material, and a drive mechanism comprising one or more magnets placed along the conveyor belt for generating a magnetic field for exerting a driving force on one or more of the drive bodies near the magnets, wherein the conveyance path comprises a bend and wherein the drive mechanism is placed in the bend.

The conveyor belt according to the invention comprises drive links that each have a drive body of a magnetic material. As a result the movements of the drive links in the conveyor can be influenced by means of magnetic fields, particularly for driving the conveyor belt. The drive means according to the invention comprise one or more magnets placed along the conveyance path for generating a magnetic field for exerting a driving force on the drive links that have been provided with a magnetic material. The magnetic fields that are placed along the conveyance path by the one or more magnets have a certain range over which the magnetic fields are able to exert a driving force on a drive body in a drive link. Said range forms a drive track for the one or more magnets in question. Within said drive track links with drive bodies can be driven.

The movements of the drive links in a conveyance direction of the conveyor can be influenced by means of magnetic fields. In the device according to the invention the magnetic fields can moreover be used for guiding the conveyor belt through the bend. The magnets of the drive mechanism, apart from being a driving force, can also be adapted for exerting a force on the drive links that is directed substantially transverse to the conveyance path. Said transverse force can be utilised for guiding the links through the bend. In this way for instance at least at the location of the drive mechanism, a mechanical guidance of the conveyor belt through the bend may no longer be necessary, as a result of which friction of the conveyor belt when moving along the conveyance path can be reduced.

A further advantage of such a device is that physical contact between the drive means and the links is not necessary in order to drive them. As a result wear due to the drive means can at least be limited or even be avoided, as a result of which maintenance/repairs need to take place less often.

A further advantage of reducing or avoiding wear is a reduction of wearing products that constitute a source of pollution. This is among others advantageous for using the conveyor according to the invention in for instance the food industry, where pollution should be minimised.

In one embodiment at least the drive links are built up from a number of particularly elongated modules, which at their longitudinal ends have been provided with coupling means that inter-engage for snug-fitting coupling of the modules one to the other and forming a rotation-fixed connection in the plane of the belt, wherein at least one of the modules of a drive link comprises the drive body.

Due to said coupling adjacent modules inter-engage and mutual displacement and rotation is counteracted and they form one unity as it were. In the links thus built up an optimum transmission of forces in transverse direction can take place.

Coupling modules into links prior to connecting the links to each other can take place easily in a controlled manner. Moreover a drive link can easily be formed by placing at least one module with drive body in the link. In this way the series of links forming the conveyor belt can largely be built up by using two types of modules; a large number of first modules without drive body and for each drive link at least one second module including drive body.

In one embodiment the drive body is placed in the link, preferably in the plane of the link.

In one embodiment the drive body is placed near an end of the link forming an edge of the conveyor belt, wherein the drive mechanism is placed near the edge of the conveyor belt.

In one embodiment the drive mechanism is placed at an outer side of the bend. In that case the magnets of the drive mechanism are adapted for exerting a rejecting force on the drive links which force is directed substantially transverse to the conveyance path.

In one embodiment the belt conveyor comprises one or more magnet means placed along the conveyance path for generating a magnetic field for guiding the conveyor belt, at least its drive links, through the bend. Said magnet means are preferably placed in or near a bend in the conveyance path where no drive mechanism is placed. The magnet means may form a guidance device for guiding the conveyor belt through the bend.

In one embodiment the magnet means comprise electromagnets. As a result the strength of the magnetic fields can be adjusted to the desired values, as a result of which the operation of the conveyor can be optimised.

According to a further aspect the invention provides a belt conveyor comprising a conveyor belt extending along a conveyance path, comprising a series of elongated support members or links for supporting goods to be conveyed, which links extend transverse to the belt, and a series of coupling means for coupling the links one to the other, wherein a number of first coupling means each comprise a drive body of a magnetic material, and a drive mechanism comprising one or more magnets placed along the conveyor belt for generating a magnetic field for exerting a driving force on one or more of the drive bodies near the magnets.

Instead of arranging drive bodies of a magnetic material on or in the links, the drive bodies are placed on or in the coupling means. In that way it will not be necessary to utilise specially formed links or link members and the known links that are usually made of synthetic material, can be used.

In one embodiment the coupling means comprise connecting rods. In one embodiment the conveyance path comprises a bend and the drive mechanism is placed in the bend.

According to a further aspect the invention provides a helical conveyor comprising a belt conveyor as described above, further comprising a framework for supporting a helical conveyance path having a first number of windings or storeys placed above one another; wherein the conveyor belt is placed on the helical path and able to move over it; wherein the drive mechanism comprises one or more drive units at a second number of windings or storeys placed above one another, wherein the second number is smaller than or equal to the first number; wherein the helical conveyor comprises a freely rotatable support roller which is positioned within the helical path for having a side of the conveyor belt that faces the inner side of the helical path support against it, and wherein the drive mechanism is placed at an outer side of the helical path.

Instead of the rotatable drum positioned within the helical path according to the state of the art, the helical conveyor according to the invention is provided with a freely rotatable support roller, which is positioned within the helical path for having a side of the link belt that faces the inner side of the helical path support against it, particularly near the location where the drive mechanism is placed at the outer side of the helical path and engages onto the outer side of the link belt. The conveyor belt is thus passed between the support roller at the inner side of the conveyance path and the drive mechanism at the outer side of the conveyance path. As the freely rotatable support roller in the helical conveyor according to the invention is only used for having the conveyor belt support against it, and not for driving the conveyor belt using friction, it can be designed much more lightweight, the conveyor belt will substantially not slip along the support roller, and the diameter of the support roller can be smaller than an inner diameter of the helical path.

By substantially avoiding slippage between the conveyor belt and the support roller, the link belt will be less prone to wear which may result in reducing pollutions due to wearing products and/or extending the lifespan of particularly the conveyor belt.

In one embodiment the support roller and the drive mechanism are placed on either side of the conveyor belt. In one embodiment the drive mechanism is placed such with respect to the support roller that the support roller is able to suitably absorb possible radial forces exerted by the drive mechanism on the conveyor belt. In one embodiment the drive mechanism is placed substantially radial with respect to the support roller.

In one embodiment the drive mechanism, for each of the second number of windings placed above one another, comprises a drive unit for drivingly engaging a side of the modular conveyor belt that faces the outer side of the helical path. In that way the forces exerted by the drive mechanism on the modular conveyor belt can be distributed over a number of locations along the length of the helical path, particularly over a number of locations situated above one another along the helical path.

In one embodiment the drive unit extends at least partially above an edge area of the modular conveyor belt. In this embodiment the conveyor belt is confined in vertical sense near the drive element between the helical path at the lower side and at least a part of the drive unit at the upper side. Said confinement ensures that the conveyor belt at least near the drive element cannot fold upwards, as a result of which the operational connection between the drive element and the conveyor belt is guaranteed.

In one embodiment the drive unit extends at least partially below an edge area of the modular conveyor belt.

From a further aspect the invention provides a helical conveyor comprising a belt conveyor as described above, and further comprising: a framework for supporting a helical conveyance path having a first number of windings or storeys placed above one another; wherein the conveyor belt is placed on the helical path and able to move over it; wherein the drive mechanism comprises one or more drive units at a second number of windings or storeys placed above one another, wherein the second number is smaller than or equal to the first number; wherein the drive mechanism is placed at an inner side of the helical path.

As already stated above the movements of the drive links in a conveyance direction of the conveyor can be influenced by means of magnetic fields, but moreover the conveyor belt can be guided trough the bend. The magnets of the drive mechanism apart from supplying a driving force can also be adapted for exerting a force on the drive links which force is directed substantially transverse to the conveyance path. Said transverse force can be utilised for guiding the links through the bend. Preferably the drive mechanism is placed at an inner side of the bend. In that case the magnets of the drive mechanism are adapted for exerting a rejecting force on the drive links which force is directed substantially transverse to the conveyance path. The drive mechanism at the inner side, at least at the location of the drive mechanism, replaces the drive drum or support roller within the helical path and is able to keep the conveyor belt at the desired radial distance by means of a force that is directed substantially radially to the outside. In that way at least at the location of the drive mechanism, a mechanical guidance of the conveyor belt at the inner side of the helical conveyor may no longer be necessary, as a result of which friction of the conveyor belt when moving along the conveyance path can be reduced.

According to a further aspect the invention provides a drive mechanism suitable and intended for a belt conveyor or a helical conveyor as described above.

The invention further provides an apparatus for subjecting goods, especially bakery goods, to a treatment, comprising a conveyor belt according to the invention.

The aspects and measures described in this description and the claims of the application and/or shown in the drawings of this application may where possible also be used individually. Said individual aspects may be the subject of divisional patent applications relating thereto. This particularly applies to the measures and aspects that are described per se in the sub claims.

SHORT DESCRIPTION OF THE DRAWINGS

The invention will be elucidated on the basis of a number of exemplary embodiments shown in the attached drawings, in which:

Figure 1 shows a top view of a part of a conveyor belt according to the invention, in a bend track;

Figure 2 shows a detail of the belt of figure 1 ;

Figure 3 shows a cross-section according to Ill-Ill in figure 2; Figure 4 shows a view of an embodiment of a helical conveyor according to the state of the art;

Figure 5 shows a view in cross-section of the helical conveyor according to figure 4;

Figure 6 shows a schematic top view of an exemplary embodiment of a helical conveyor according to the invention;

Figure 7 shows a schematic side view of exemplary embodiments of the helical conveyor according to figure 6;

Figure 8 shows a schematic top view of a second exemplary embodiment of a helical conveyor according to the invention; and

Figure 9 shows a schematic side view of exemplary embodiments of the helical conveyor according to figure 8.

DETAILED DESCRIPTION OF THE DRAWINGS

The conveyor belt 1 shown in figure 1 , largely corresponds with the one shown in applicant's European patent application 90.202922 and is laid on guides 3. The belt is built up from transversely oriented links 4, that are connected to each other by connecting rods 20. At the inside radius the links 4 may run into a permanent side guide 2 (not shown) or be propelled by a driven drum.

The links 4 are substantially zig-zag shaped, having "hills" 5 with accommodation spaces 9 situated in between them and "valleys" 6 with accommodation spaces 8 situated in between them, the "valleys" 6 extending in the accommodation spaces 9 of a next link 4 and the "hills"

5 in the accommodation spaces 8 thereof. The "hills" and "valleys" 5 and

6 of a link are formed as a unity with each other from synthetic material and are connected to each other via bodies 7. The "hills" 5 are provided with a spacious passage 10 for a rod 20, and the "valleys" 6 are provided with a narrow passage 1 1 for a rod 20. In between the bodies 7 the "valleys" 6 have a circular cross-section, coaxial to the passages 1 1. The links 4 are composed of an edge module 4a, an edge module 4b and one or more -depending on the desired belt width- intermediate modules 4c. The edge module 4a sits on the guide 3. The edge module 4b also sits on a guide 3 and is guided sideward or driven, respectively, by guide 2.

Near an end portion 13 the edge modules 4a and 4b have been provided with a drive body 131 of a magnetic material. A drive mechanism 100 comprising one or more magnets placed along the conveyor belt 1 for generating a magnetic field is adapted for together with the drive bodies 131 forming a linear motor for generating a driving force on one or more of the drive bodies 131.

The modules 4a-4c are coupled to each other by couplings 14, see figure 2 and 3. The one module, for instance 4c, has dovetailed protrusions 15 extending over the full height, which protrusions have slanting sides 18 and a surface 19 oriented in transverse direction, two surfaces 21a,b oriented in transverse direction being present adjacent to the protrusion

15. The other module, for instance 4a, at the opposite end has a continuing recess 16, having slanting sides 17 and a surface 20 oriented in transverse direction, formed correspondingly for a snug, tight fitting with protrusions 15, two surfaces 22a, b oriented in transverse direction being present at the recess 16. After the modules 4a, 4b and 4c have been coupled, the surfaces 17-18, 21a,b-22a,b and 19-20 sit tightly against each other. The coupling here extends in width {longitudinal direction of the belt) and height over the entire area where the modules meet each other.

The modules thus already form one well-manageable unity, capable of absorbing tensile forces. Due to the dovetail the rigidity of the coupling

14 against bending in the horizontal and in the vertical plane can be large.

It can furthermore be seen that the passages 1 1 extend through the couplings 14. After the rods 20 have been passed through the passages 1 1 , fitting yet axially movable, they are retained outwardly by pins 12 at both ends, and therefore confined, in the end portions 13 of the edge modules 4a and 4b. The modules cannot run apart due to the couplings between the modules. As a result of a frictional fitting of their coupling members the modules can be retained against mutual displacement in a direction perpendicular to the belt. The rod 20 as well can rule out such a movement due to snug fitting in the modules.

As an alternative of the edge modules 4a and 4b which near an end portion 13 are provided with a drive body 131 of a magnetic material, the connecting rods 20, at least near one or both ends thereof, may also be provided with magnetic material for forming a drive body.

Figure 4 shows a helical conveyor according to the state of the art consisting of a framework of girders 41 and posts 42. On the posts 42 that have been positioned according to a polygon, inwardly oriented holders 43 are disposed which by means of a helical path 44 offer support to a conveyor belt 45. Within the helical path 44 a drum 46 is positioned which can rotatably be driven about a vertical axis 47 by means of a motor (not shown). The drum 46 is covered with spaced apart substantially vertical beams 49. When the conveyor belt 45 is kept at the right tension, the rotating drum 46 takes along the conveyor belt 45. Some intentional slippage occurs in the process. In figure 5, the known helical conveyor is shown in cross-section, along a plane substantially transverse to the vertical axis 47.

Figure 6 shows a first exemplary embodiment of a helical conveyor 60 according to the invention. Figure 6 shows a top view that extends substantially transverse to the axis of symmetry of the helical conveyor 60. The helical conveyor 60 according to this first exemplary embodiment comprises a framework comprising girders 61 and posts 62. On the posts 62 outwardly oriented outriggers 63 are disposed which, by means of the guides 64 that are placed in a helical path on the outriggers 63, offer support to the conveyor belt 65.

Within the helical path a number, in this example four, of freely rotatable support rollers 66 are disposed for having a side 151 of the modular conveyor belt 65 facing the inner side of the helical path support against it. The support rollers 66 are placed along a substantially vertical axis so as to be freely rotatable. The support rollers 66 are for instance at their upper and lower sides connected to further girders (not shown) of the framework. The view of figure 6 shows a further advantage of the device according to the invention. The framework namely can be substantially situated within the helical path. As outside of the helical path vertical posts 62 substantially need not be present, the conveyor belt 65 can easily be placed on the guides 64 of the helical path. In one embodiment, the modular belt sits unfastened, particularly detached on the guides 64 of the helical path.

The helical conveyor 60 according to this first exemplary embodiment is provided with a drive mechanism in the form of magnets 67 which are placed at an outwardly facing side 152 of the modular conveyor belt 65 for engagement with the drive bodies 13 of the conveyor belt. The drive magnets 67 are placed substantially radially opposite one of the support rollers 66, as shown in figure 6.

As shown in figure 7 the helical conveyor 60 is provided with a number of drive magnets 67 placed above one another, each able to drive the conveyor belt 65 at a storey of the helical conveyor 60.

Figure 8 shows a second exemplary embodiment of a helical conveyor 80 according to the invention. This second exemplary embodiment also comprises a framework provided with girders 81 and posts 82. On the posts 82 outwardly oriented outriggers 83 are disposed, which are provided with guides 84 forming a helical path for having the conveyor belt 85 support against it. At the location of the conveyor belt 85, the posts 82 situated near the helical path are provided with freely rotatable support rollers 86.

In this embodiment the freely rotatable support rollers 86 substantially do not extend over the full height of the helical conveyor 80, but only at the location of the helical path are the posts 82 provided with support rollers of a limited height that are adapted for adequately having a side 251 of the modular conveyor belt 85 facing the inner side of the helical path support against them. Said combination of vertical posts 82 with support rollers 86 placed thereon is schematically shown in figure 9. In the second exemplary embodiment, as shown in the top view of figure 8, a drive mechanism in the form of magnets 87 is placed at an inwardly oriented side 252 of the modular conveyor belt 85 for engagement with drive bodies 13 of the conveyor belt 85.

As shown in figure 9 the helical conveyor 80 is provided with a number of drive magnets 87 placed above one another, which are each able to drive the conveyor belt 85 at a storey of the helical conveyor 80. In that case the magnets 87 of the drive mechanism are adapted for exerting a rejecting force on the conveyor belt 85 which force is directed substantially transverse to the conveyance path. The drive mechanism 87 at the inner side, at least at the location of the drive mechanism, replaces the drive drum or support roller 86 within the helical path and is able to keep the conveyor belt at the desired radial distance by means of a force that is directed substantially radially to the outside.

The above description is included to illustrate the operation of preferred embodiments of the invention and not to limit the scope of the invention. Starting from the above explanation many variations that fall within the spirit and scope of the present invention will be evident to an expert.

For instance a helical conveyor according to the invention may be provided with several drive mechanisms placed at a circumference. In addition a drive mechanism placed adjacent to a first helical conveyor can also drive a further adjacently placed second helical conveyor.

Claims

1 . Belt conveyor comprising a conveyor belt extending along a conveyance path, comprising a series of elongated support members or links for supporting goods to be conveyed, which links extend transverse to the belt, and a series of connecting rods for connecting the links one to the other, wherein a number of first links each comprise a drive body of a magnetic material, and a drive mechanism comprising one or more magnets placed along the conveyor belt for generating a magnetic field for exerting a driving force on one or more of the drive bodies near the magnets, wherein the conveyance path comprises a bend and wherein the drive mechanism is placed in the bend.

2. Belt conveyor according to claim 1 , wherein at least the first links are built up from a number of particularly elongated modules, which at their longitudinal ends have been provided with coupling means that inter-engage for snug-fitting coupling of the modules one to the other and forming a rotation-fixed connection in the plane of the belt, wherein at least one of the modules of a first link comprises the drive body.

3. Belt conveyor according to claim 1 or 2, wherein the drive body is placed in the link, preferably near an end of the link forming an edge of the conveyor belt.

4. Belt conveyor according to claim 3, wherein the drive mechanism is placed near an edge of the conveyor belt.

5. Belt conveyor according to any one of the preceding claims, wherein the drive mechanism is placed at an outer side of the bend.

6. Belt conveyor according to any one of the preceding claims, further comprising one or more magnet means placed along the conveyance path for generating a magnetic field for guiding the conveyor belt, at least its drive links, through the bend.

7. Belt conveyor comprising a conveyor belt extending along a conveyance path, comprising a series of elongated support members or links for supporting goods to be conveyed, which links extend transverse to the belt, and a series of coupling means for coupling the links one to the other, wherein a number of first coupling means each comprise a drive body of a magnetic material, and a drive mechanism comprising one or more magnets placed along the conveyor belt for generating a magnetic field for exerting a driving force on one or more of the drive bodies near the magnets.

8. Belt conveyor according to claim 7, wherein the coupling means comprise connecting rods.

9. Conveyor belt according to claim 7 or 8, wherein the conveyance path comprises a bend, and wherein the drive mechanism is placed in the bend.

10. Helical conveyor comprising a belt conveyor according to any one of the preceding claims further comprising a framework for supporting a helical conveyance path having a first number of windings or storeys placed above one another; wherein the conveyor belt is placed on the helical path and able to move over it; wherein the drive mechanism comprises one or more drive units at a second number of windings or storeys placed above one another, wherein the second number is smaller than or equal to the first number; wherein the helical conveyor comprises a freely rotatable support roller which is positioned within the helical path for having a side of the conveyor belt that faces the inner side of the helical path support against it, and wherein the drive mechanism is placed at an outer side of the helical path.

1 1. Helical conveyor according to claim 10, wherein the support roller and the drive mechanism are placed on either side of the modular conveyor belt.

12. Helical conveyor according to claim 10 or 1 1 , wherein the drive mechanism is placed substantially radially opposite the support roller.

13. Helical conveyor according to claim 10, 1 1 or 12, wherein the drive mechanism, for each of the second number of windings placed above one another, comprises a drive unit for drivingly engaging a side of the modular conveyor belt that faces the outer side of the helical path.

14. Helical conveyor comprising a belt conveyor according to any one of the claims 1 -9, and further comprising: a framework for supporting a helical conveyance path having a first number of windings or storeys placed above one another; wherein the conveyor belt is placed on the helical path and able to move over it; wherein the drive mechanism comprises one or more drive units at a second number of windings or storeys placed above one another, wherein the second number is smaller than or equal to the first number; wherein the drive mechanism is placed at an inner side of the helical path.

15. Helical conveyor according to claim 14, wherein the drive mechanism, for each of the second number of windings placed above one another, comprises a drive unit for drivingly engaging a side of the modular conveyor belt that faces the inner side of the helical path.

16. Helical conveyor according to claim 13 or 15, wherein the drive unit extends at least partially above an edge area of the modular conveyor belt.

17. Helical conveyor according to claim 13, 15 of 16, wherein the drive unit extends at least partially below an edge area of the modular conveyor belt.

18. Drive mechanism suitable and intended for a belt conveyor or a helical conveyor according to any one of the preceding claims.

19. Belt conveyor or helical conveyor provided with one or more of the characterising measures described in the attached description and/or shown in the attached drawings.

20. Drive mechanism provided with one or more of the characterising measures described in the attached description and/or shown in the attached drawings.

21. Method provided with one or more of the characterising measures described in the attached description and/or shown in the attached drawings.

22. Conveyor belt provided with one or more of the characterising measures described in the attached description and/or shown in the attached drawings.

23. Apparatus for subjecting goods, particularly bakery goods, to a treatment, comprising a conveyor belt according to any one of the preceding claims.