WO2019240571A1

WO2019240571A1 - Modular conveyor belt transfer system

Info

Publication number: WO2019240571A1
Application number: PCT/NL2019/050349
Authority: WO
Inventors: Cornelis Hendrik Mijndert Menke
Original assignee: Rexnord Flattop Europe B.V.
Priority date: 2018-06-11
Filing date: 2019-06-11
Publication date: 2019-12-19
Also published as: EP3802376A1; NL2021102B1

Abstract

A transfer system comprising a pair of modular conveyor belts that is arranged end to end, each conveyor belt having a pitch of the modules along a length of the conveyor belt of 1 inch (about 25.4 mm) or less, and including a plurality of adjacent modules across a width of the conveyor belt, the conveyor belts each extending along a top run located in a conveying plane of the transfer system, and at the facing ends thereof extending respectively out of and into the conveying plane about a return, and respectively from and to the return further extending along a bottom run that is located below the conveying plane. Each return includes a guide surface that extends in width direction of the conveyor belt with a curved cross section. The transfer system further includes a cover surface that extends in the conveying plane to close a gap between the top runs at the facing ends of the conveyor belts.

Description

Title: Modular conveyor belt transfer system

The invention relates to a transfer system, comprising a pair of modular conveyor belts that is arranged end to end.

Modular conveyor belts are generally known, and are for example used for conveying discrete products such as plastic bottles. The belts are built up of modules of which the top surfaces form a conveying surface for supporting the products to be conveyed. The modules are usually

manufactured by molding, and are often manufactured from a plastics material. The length of the belt may be varied by placing modules in a row in a conveying direction, and by coupling successive modules in the row with hinge pins that extend transverse to the conveying direction. The width of the belt can be varied by placing several modules next to each other transverse to the conveying direction.

The belts are usually of endless design, so that they can circulate over a conveying track using returns, usually a set of sprocket wheels at each end. Such sprocket wheels are provided with teeth that engage the bottom of the modular belt. To ensure that there are sufficient teeth in engagement with the belt, the sprocket wheels typically need to have a relatively large diameter. The modular nature of the belt causes the belt to round the sprocket wheels in a polygonal shape. In practice, this polygonal shape can cause the conveying surface to move up- and down slightly where it starts to round the sprocket wheel, which effect can be lessened when the return is chosen to be a sprocket wheel of relatively large diameter.

When products are transferred from two subsequent conveyor belts that are aligned in conveying direction, e.g. when the length of a single modular conveyor belt is insufficient, a so called end to end transfer system may be used.

An end to end transfer system typically comprises a pair of modular conveyor belts that is arranged end to end, each conveyor belt having a pitch of the modules along a length of the conveyor belt, and including a plurality of adjacent modules across a width of the conveyor belt, the conveyor belts each extending along a top run located in a conveying plane of the transfer system, and at the facing ends thereof extending out of respectively into the conveying plane about a return, and further to or from the return along a bottom run that is located below the conveying plane.

The relatively large diameter of the sprocket wheels causes a relatively large gap in the conveying plane at the facing ends of the conveyor belts, which is often too large for products to be conveyed from one belt to the next without toppling over. To address this, it is known to provide a slide-over plate between the conveying surfaces of the successive belts such that a smooth transition can be realized at the facing sprocket wheels. A disadvantage of such slide-over plate is that when finishing a product run, some products may be left behind in a so-called‘dead-zone’ of the slide-over plate.

In order to have a smooth transition between successive belts without the problem of the dead-zone mentioned above, it has been proposed to place the ends of the conveyor belts as closely together as possible, while reducing the pitch of the modules to less than 1 inch (about 25.4 mm) and while embodying the return as a guide surface that extends in width direction of the conveyor belt with a curved cross section. By using a small pitch and a guide surface as a return instead of a sprocket wheel, the modular conveyor belts can be arranged end to end without using a slide- over plate. In practice, when using so-called‘nose-overs’ as guides, the gap can be reduced to such an extent that a smooth transition can be achieved such that the problem of products toppling over is mitigated for most products. The pitch may even be between ½ inch (about 12.7mm) and ¼ inch (about 6.35 mm), e.g. be about V3 inch (about 8.5 mm).

Although quite satisfactory for reliably transferring products, it has been found that such an end-to-end transfer arrangement can in certain situations be hazardous. In particular when only one conveyor belt of the pair is moving, fingers of an operator may get pinched between the ends of the successive conveyor belts, e.g. when an operator is trying to remove objects that got entangled between the belts, or debris that have

accumulated there.

An object of the invention therefore is to provide a transfer system that mitigates the above mentioned drawback, while maintaining or improving the reliability of the transfer of products.

Thereto, the invention provides a transfer system comprising a pair of modular conveyor belts that is arranged end to end, each conveyor belt having a pitch of the modules along a length of the conveyor belt of 1 inch (about 25.4 mm) or less, and including a plurality of adjacent modules across a width of the conveyor belt, the conveyor belts each extending along a top run located in a conveying plane of the transfer system, and at the facing ends thereof extending out of respectively into the conveying plane about a return, and then extending from respectively to the return along a bottom run that is located below the conveying plane, each return including a guide surface that extends in width direction of the conveyor belt with a curved cross section, the transfer system further including a cover surface that extends in the conveying plane to close a gap between the top runs at the facing ends of the conveyor belts.

The cover surface acts as a protective barrier that restricts access to the gap such that fingers of an operator can not get pinched between the ends of the successive conveyor belts. In addition, entanglement of objects and accumulation of dirt in the gap can be reduced, thereby improving the operative stability and reliability of the transfer system. In addition, as the cover surface may also prevent a protruding foot portion of a conveyed product from entering into the space below the gap in the conveying surface, stable transfer of products may be enhanced. Preferably, in length direction of the conveyor belt, the dimension of the cover surface is less than three times the pitch of the modules of the conveyor with the smallest pitch of the pair of conveyors, more preferably less than two times the pitch of the modules. Preferably, the dimension of the cover surface is between a half and one and a half times the pitch of the modules, for example the

dimension of the cover surface may be between ½ inch (about 12.7 mm) and ¼ inch (about 6.35 mm), e.g. be about 'A; inch (about 8.5 mm).

When the cover surface includes a support that is arranged to extend in the space between the returns located below the gap in the conveying plane that is closed by the cover surface, it can be achieved that the cover surface remains secured in place during use. The support of the cover surface e.g. allows mounting by screws into a body of the conveyor support at side edges of the conveyor belts, so that a stable and reliable construction can be realized relatively easily. In addition, the support may be used to fill the space below the gap in the conveying surface, so that space for entrapment or accumulation of debris is limited.

By spacing the facing ends of the conveyor belts apart, and by designing the support to include a part that extends through an interspace between the facing ends of the conveyor belts, an even more stable and reliable construction can be realized. This is particularly useful in providing support for the cover surface across the width of the conveyor belt, which width can be significant due to the plurality of modules being arranged transverse to the conveying direction.

The support may e.g. be integrally formed with the cover surface to form a profile, and may have a width in the range of about 150 mm - 1100 mm, in particular about 170 mm - 1020 mm. When the support extends through the interspace between the facing ends of the conveyor belts, the height may be chosen relatively largely, such that it may be mounted into the side of a body of the conveyor support at side edges of the conveyor belts without sagging. This way, the support may be clear of the conveyor belt, i.e. be suspended freely. The support may e.g. be mounted to brackets that extend longitudinally along the length direction at opposing side edges of the conveyor belts. By mounting the support only at its sides to the conveyor body, the construction may be facihtated as there is no need to provide an additional frame part to suspend the support.

The height of the support or profile may e.g. be in the range of about 50 - 90 mm, in particular about 60 - 80 mm. The maximum length of the support or profile in conveying direction may e.g. be in the range of about 30 -10 mm, in particular about 20 - 10 mm. The maximum length may be at the cover surface. The minimum length may e.g. be about 5 mm, at the point where the conveyors are closest together. The cover surface of the support or profile may be of plastics material, e.g. HDPE. The support or profile may be made of plastics material, e.g. a machined beam or extruded profile of plastics material. The support or profile may comprise metal or alternatively be made of metal, e.g. stiffening rods that extend between sides of the conveyor body. To further prevent sagging, the support or profile may be carried on threaded rods that extend between the sides of the conveyor body, and that e.g. may be tensioned. When a radius of curvature of the curved guide surface corresponds to the pitch of the modular conveyor belt or is less than the pitch, it can be achieved that the module when rounding the return can follow the rounded contour i.e. circular form of the return relatively well. In practice, during rounding this results in a smooth and reliable operation of the transfer system. The diameter of curvature, which is twice the radius of curvature, may for example be between ½ inch (about 12.7 mm) and V» inch (about 3.2 mm), e.g. be about ¼ inch (about 6.35 mm).

When the guide surface is a passive surface, it can be

implemented cost-effectively. By providing a stationary guide surface, the design can be simplified further and a reliable construction can be achieved as the guide can be provided without moving parts. The cover surface can advantageously be designed to extend across the conveyor belt, preferably continuously. When the support also extends across the conveyor belt, a reliable construction can be realized. Applying these features in combination and implementing them in a continuous fashion provides for a particularly simple and reliable

construction.

By designing the cover surface and the support to be integrally formed as a profile, a particularly reliable construction can be realized cost- effectively.

When the support includes a cross section that broadens out towards the cover surface, the stiffness of the cover surface can be improved. When the support is substantially tapered and/or T-shaped in cross section, the cover surface may be well supported near its edges, such that a reliable construction can be realized cost-effectively.

When the support includes a top core that substantially fills an upper part of the space between the return adjacent the top runs of the conveyor belts, a narrow fit can be realized such that debris and other foreign objects are impeded from entering the space. This way, a very reliable operation of the transfer system can be achieved cost-effectively.

By providing a further part that extends through the interspace between the facing ends of the conveyor belts, and that connects to the top core, the stiffness of the construction can be improved.

When the support includes a bottom core that substantially fills a lower part of the space between the returns adjacent the bottom runs of the conveyors, and that connects to the further part, the stiffness of the construction can be further improved. In this manner, a reliable

construction can be achieved cost-effectively.

By providing both a top and bottom core that is connected via a further part that extends through the interspace between the facing ends of ί the conveyors, a self locking structure is achieved that facilitates that the cover surface remains positioned in the conveying plane.

When the support is concavely shaped at at least one side facing the return, and cooperates with the guide surface to define a narrow, curved slot there between for passage of the modules of the modular conveyor belt, a self-locking construction can be realized cost-effectively. In particular, the support may then be reliably positioned with its cover surface in the conveying plane relatively easily, as it is prevented from migrating out of its position in the conveying plane by interaction with the top surfaces of the modules in the return part, and may even be at least partially supported thereon. Thereby, a particularly stable and reliable construction can be achieved. In the context of this application, self-locking relates to the tendency of the support to secure itself with the cover surface positioned in the conveying plane when the conveyor belts are driven during operation of the transfer system.

By designing the support to be substantially hour glass shaped, a particularly elegant and cost-effective design can be realized, that achieves a particularly stable and reliable construction.

In an advantageous manner, a connecting bracket may be provided which forms a connection between the support of the conveyor belts and the support of the cover surface, such that a stable and reliable construction can be realized relatively easily.

It should be noted that the technical features described herein may each on its own be embodied in a transfer system, i.e. isolated from the context in which it is described, separate from other features, or in combination with only a number of the other features described in the context in which it is disclosed. Each of these features may further be combined with any other step or feature disclosed, in any combination.

The invention will be further elucidated on the basis of an exemplary embodiment represented in the drawings. In the drawings: Fig. 1 shows a schematic perspective view from the top of a transfer system according to the invention;

Fig. 2 shows a schematic cross section of the transfer system of Fig. 1 along the line A- A.

In the Figures identical or corresponding parts are represented with the same reference numerals. The drawings are only schematic representations of a preferred embodiment of the invention, which is given by manner of non-limiting exemplary embodiment.

Fig. 1 shows a schematic perspective view from the top of a transfer system 1. The transfer system 1 comprises a pair 2 of modular conveyor belts 3, 4. The pair 2 of modular conveyor belts 3, 4 is arranged end to end, and are successive in length direction L. The conveyors 3, 4 are of a modular design with a row of modules 5 successive in length direction L. Successive modules 5 are hingedly connected to each other with the aid of hinge pins that extend transversely across the conveyor belt 3, 4. Each conveyor belt 3, 4 has a pitch of the modules 5 along the length direction L of the conveyor belt of 1 inch (about 25.4 mm) or less. In this example the pitch is about ½ inch (about 12.7 mm). Each conveyor belt is embodied as a mat that includes a plurality of adjacent modules 5 across a width direction W of the conveyor belt 3, 4. Top surfaces of the modules 5 together

constitute a conveying face of the conveyor belt. The conveyor belts 3, 4 each extend along a top run 6 located in the conveying plane P of the transfer system 1. At the top run 6, the conveying face of the conveyors is arranged to support products to be conveyed in a conveying plane P.

As can be seen in Fig. 2, the conveyor belts 3, 4 at facing ends 7 thereof extend out of respectively into the conveying plane P about a return 8. From respectively to the returns 8, the conveyor belts 3, 4 further extend along a bottom run 9 that is located below the conveying plane P. Each return 8 includes a guide surface 10 that extends in width direction W of the conveyor belt 3, 4 with a curved cross section. In this embodiment, the guide surface is part of a passive guide surface. In particular, here, the guide surface is part of a stationary guide surface that is embodied as a so-called nose-over. Alternatively, passive guide surfaces can e.g. be embodied as passive rollers that are driven by the respective conveyor belts 3, 4 during use.

The transfer system 1 further includes a cover surface 11 that extends in the conveying plane P to close a gap 12 in the conveying plane P between the top runs 6 at the facing ends 7 of the conveyor belts 3, 4. The cover surface 11 is placed at an end-to-end transition between the successive modular conveyor belts 3, 4. The conveyor belts 3, 4 are endless, and circulate between returns 8, of which only the facing returns are shown in Fig. 2. The conveyor belts 3, 4 each circulate about further returns (not shown). The conveyor belts 3, 4 are driven with drive wheels, for instance sprocket wheels not represented in the drawings. The sprocket wheels may e.g. be arranged between the returns.

Fig. 2 shows a schematic cross section of the transfer system 1 of Fig. 1 along the hne A-A. The cover surface 1 includes a support 13 that extends in the space between the returns 8. The space is located below the gap 12 that is closed by the cover surface 11. In the exemplary embodiment, the cover surface 11 and support 13 are integrally formed as a profile 14, e.g. an extruded profile that is substantially hour glass shaped.

The cover surface 11 and the support 13 are in this exemplary embodiment integrally formed as a profile 14 that is machined out of a beam of HDPE. The profile 14 has a width of 1020 mm, a height of 80 mm, and a maximum length in conveying direction of 20 mm, at the cover surface. The minimum is 5 mm, at the point where the conveyors are closest together.

The support part 13 of the profile 14 extends through the interspace between the returns 8 at the facing ends of the conveyor belts 3,4 and is mounted into the side of a body of the conveyor support at side edges of the conveyor belts without sagging. In particular, the support part 13 of the profile 14 is mounted to brackets that extend longitudinally along the length direction at opposing side edges of the conveyor belts 3, 4. The support is be clear of the conveyor belts 3, 4 and is suspended freely.

Alternatively, the cover surface 11 and support 13 may be formed as parts that are arranged for mounting together, for example using a screw connection, an adhesive connection or a welded connection. The returns 8 of a pair 2 of modular conveyor belts 3, 4 arranged in end-to-end transition may be coupled via a connecting element (not represented) e.g. a connecting bracket extending along the length direction L at opposing side edges of the conveyor belts 3, 4. In this manner, the support 13 can be coupled via the connecting element to the returns 8 for a stable and reliable construction. For instance, the support may be bolted or screwed to the connecting element, which can in turn be bolted or screwed to the returns 8. The support 13 includes a top core 15 that substantially fills an upper part 16 of the space between the returns 8 adjacent the top run 6 of the respective conveyor belts 3, 4. The support 13 further includes a bottom core 17 that is provided with holes 18. Similar to the top core 15, the bottom core 17 substantially fills a lower part 19 of the space between returns 8 adjacent the bottom run 9 of the respective conveyor belts 3, 4. That is to say, the support 13 is concavely shaped at both sides, each facing a return 8. The support 13 cooperates with the guide surface 10 to define a narrow, curved slot 20 there between for passage of the modules 5 of the respective modular conveyor belts 3, 4. The holes 18 are arranged for mounting multiple adjacent cover surfaces 11 including supports 13 across the width direction W, for example using dowel pins, screws or bolts (not represented).

Alternatively, the cover surface 11 and support 13 can be formed as a continuous member, without holes 18 for mounting. The support 13 includes a part 21 that extends through an interspace 22 between the facing ends 7 of the conveyor belts 3, 4. This causes enlargement of the interspace 21 between the conveyor belts 3, 4 and goes against the prior art concept of placing the conveyor belts as closely together as possible in a transfer system. However, it allows for simple and reliable positioning of a cover surface, which in addition to increased safety improves stability of the products to be transferred. The support 13 includes a further part 23 that extends through the interspace 21 between the facing ends 7 of the conveyor belts 3, 4, and that connects to the top core 15. In the exemplary

embodiment of Fig. 1, the cover surface 11 and the support 13 (which support is not represented) extend continuously across the conveyor belts 3, 4 in width direction W.

The curvature of the guide surface 10 of the return 8 corresponds to a curvature of a concave bottom surface of the modules 5. This way, he modular conveyor belt can follow the curvature of the guide surface of the nose over well.

It will be clear to the skilled person that the invention is not limited to the exemplary embodiment represented here. Many variations are possible. For example the cover surface with the support can be

substantially be T-shaped in cross section, or the support can be

substantially tapered, broadening out towards the cover surface. For instance, the part of the support that substantially fills the upper part of the space between the returns adjacent the top run of the respective conveyor belts may have a triangular or cone shaped cross section. Further, the top core and bottom core might have a triangular cross section, which are inverted relative to one another and connected to each other by the further part. Furthermore, the cover surface and support may be a kit of parts that are arranged to be mounted together, for example using a screw connection, an adhesive connection or a welding connection. The conveyor belts can be designed, for instance, as metal or plastic modular conveyor belts or modular conveyor chains, but can also be of non-modular design, such as, for instance, endless rubber conveyor belts. Such variations shall be clear to the skilled person and are considered to fall within the scope of the invention as defined in the appended claims.

List of reference signs

1. Transfer system

2. Pair of modular conveyor belts 3. First conveyor belt

4. Second conveyor belt

5. Module

6. Top run

7. Facing ends

8. Return

9. Bottom run

10. Guide

11. Cover surface

12. Gap

13. Support

14. Profile

15. Top core

16. Upper part

17. Bottom core

18. Holes

19. Lower part

20. Slot

21. Part

22. Interspace

23. Further part

L. Length direction of the conveyor belt W. Width direction of the conveyor belt P. Conveying plane

Claims

1. A transfer system comprising a pair of modular conveyor belts that is arranged end to end, each conveyor belt having a pitch of the modules along a length of the conveyor belt of 1 inch (about 25.4 mm) or less, and including a plurality of adjacent modules across a width of the conveyor belt, the conveyor belts each extending along a top run located in a conveying plane of the transfer system, and at the facing ends thereof extending respectively out of and into the conveying plane about a return, and respectively from and to the return further extending along a bottom run that is located below the conveying plane, each return including a guide surface that extends in width direction of the conveyor belt with a curved cross section, the transfer system further including a cover surface that extends in the conveying plane to close a gap between the top runs at the facing ends of the conveyor belts.

2. Transfer system according to cl im 1, wherein the cover surface includes a support that is arranged to extend in the space between the returns located below the gap in the conveying plane that is closed by the cover surface.

3. Transfer system according to cl im 2, wherein the facing ends of the conveyor belts are spaced apart, and wherein the support includes a part that extends through an interspace between the facing ends of the conveyor belts.

4. Transfer system according to any one of the preceding claims, wherein a radius of curvature of the curved guide surface of the guide is equal to or less than the pitch of the modules.

5. Transfer system according to any one of the preceding claims, wherein the guide surface is a passive guide surface, preferably a stationary guide surface.

6. Transfer system according to any one of claims 2-5, wherein the cover surface and preferably the support extends across the conveyor belt, preferably continuously across the conveyor belt.

7. Transfer system according to any one of claims 2-6, wherein the cover surface and the support are integrally formed as a profile, preferably and extruded profile.

8. Transfer system according to any one of claims 2-7, wherein the support includes a cross section that broadens out towards the cover surface.

9. Transfer system according to any one of claims 2-8, wherein the support is substantially tapered or T-shaped in cross section.

10. Transfer system according to any one of claims 2-9, wherein the support includes a top core that substantially fills an upper part of the space between the returns adjacent the top runs of the respective conveyor belts.

11. Transfer system according to any one of claims 2-10, wherein the support includes a further part that extends through the interspace between the facing ends of the conveyor belts, and that connects to the top core.

12. Transfer system according to any one of 2-11, wherein the

support includes a bottom core that substantially fills a lower part of the space between the returns adjacent the bottom runs of the respective conveyor belts, and that connects to the further part.

13. Transfer system according to any one of 2-12, wherein the

support is concavely shaped at a side facing the return, and cooperates with the guide surface to define a narrow, curved slot there between for passage of the modules of the modular conveyor belt.

14. Transfer system according to any one of claims 2-13, wherein the support is substantially hour glass shaped.