High stiffness belt

Abstract

The invention provides a modular conveyor belt link of the type for use in an endless conveyor belt assembled from a plurality of such modular conveyor belt links wherein the endless conveyor belt has a bearing surface and an underside opposite the bearing surface, wherein the modular conveyor belt link has a body extending in a width direction of the modular belt link, and wherein a plurality of eyelet portions extend forward and rearward from the body, the eyelet portions spaced apart in the width direction of the modular belt link, and wherein the forward extending eyelet portions are offset relative to the rearward extending eyelet portions, wherein, when two modular conveyor belt links are pushed together, the eyelet portions on one link will cooperate with each other between the eyelet portions on the other modular belt link, and wherein holes are laterally arranged in each eyelet portion, such that when eyelet portions of two adjacent modular conveyor belt links cooperate with each other, the holes will overlap, and wherein the holes will overlap with each other when the eyelet portions of the two adjacent modular conveyor belt links cooperate with each other. The invention relates to a modular conveyor belt chain link comprising a bearing surface and an underside so as to form a through-hole from one side to the opposite side of the conveyor belt, characterized in that a reinforcing structure is embedded in the material of the modular conveyor belt chain link between the bearing surface and the underside, and wherein the reinforcing structure extends into the hole portion.

Description

Field of the Invention

[0001] The present invention relates to a modular conveyor belt link and a conveyor belt assembled from such modular conveyor belt links. One of the specific features of the modular conveyor belt link according to the present invention is that reinforcement is embedded in the modular belt link, which provides a number of advantages as discussed below. Background of the Invention

[0003] Conveyor belts assembled from multiple modular conveyor belt links are used in a variety of industries, but they present challenges in certain applications. Modular conveyor belt links, as in the case of the present invention, are typically injection-molded from polymer materials, a relatively inexpensive method for mass-producing large numbers of essentially identical modular conveyor belt links. These links are assembled into relatively inexpensive conveyor belts, which offer numerous advantages. However, certain applications, such as those in the automotive industry, where very long conveyor belts are used—perhaps 400, 500, or 600 meters long and 4 to 5 meters wide—present unique challenges.

[0004] During normal production use, these types of belts are heavily loaded, potentially exposing them to stresses of up to 80,000 Newtons per meter. Under these loads, the conveyor belt itself is under heavy load, so it's stressed. However, when the belt is unstressed, it can relax, so even small localized loads can cause a phenomenon known as pulsating. Pulsating means that localized loads will cause the belt to stretch upstream, while the force will decrease downstream. This causes fluctuations in belt speed, leading to sudden, localized movements in the belt, which can be inconvenient or even dangerous for, for example, people crossing the belt.

[0005] In order to make the belt stiffer and thus reduce this phenomenon of pulsating movement, it has been proposed to incorporate fishplates made of steel in order to stiffen the modular conveyor belt.

[0006] Typically, modular conveyor belts are assembled from modular conveyor belt links, wherein eye portions extend from the leading and trailing edges of the belt links. Transverse apertures are arranged in the eye portions such that when the eye portions of adjacent belt links engage with each other, lateral throughgoing apertures are disposed across the conveyor belt. To assemble the conveyor belt links into a conveyor belt, connecting pins are inserted through the overlapping apertures, thereby hingedly connecting adjacent modular conveyor belt links.

[0007] By inserting steel fishplates that have the same length as the modular conveyor belt modules in the direction of travel of the conveyor belt and providing holes in the fishplates that overlap the transverse holes in the belt modules, the fishplates can be inserted into the conveyor belt structure so that the connecting pins will also pass through the holes in the fishplates. An example of this construction is disclosed in EP 0916598A1. When the fishplates overlap, a more or less continuous steel belt is created within the conveyor belt structure. In this way, stresses are transferred to the steel structure (the fishplates), which is stronger than the polymer structure of the modular conveyor belt links, thereby achieving a very rigid conveyor belt.

[0008] However, these constructions present several disadvantages. The mixing of materials places special demands on, for example, sprockets and shafts. Furthermore, the polymer portion of the belt wears differently from the steel portion, so these portions tend to wear against each other, reducing the life expectancy of such combined belts. Another issue is that the physical properties of the materials differ regarding temperature-induced expansion and contraction, so different portions of the belt may move relative to each other, creating deflection in the belt and causing additional wear. An example of such a construction incorporating steel fishplates is disclosed in EP1932781.

[0009] Purpose of the Invention

[0010] It is therefore an object of the present invention to provide an improved modular conveyor belt link which does increase the stiffness of the belt link but at the same time solves some of the problems mentioned above.

[0011] Description of the Invention

[0012] Thus, the present invention provides a modular conveyor belt link of the type for use in an endless conveyor belt assembled from a plurality of such modular conveyor belt links, wherein the endless conveyor belt has a load-bearing surface and an underside opposite the load-bearing surface, wherein the modular conveyor belt link has a body extending in the width direction of the modular belt link, and wherein a plurality of eyelet portions extend forwardly and rearwardly from the body, the eyelet portions being spaced apart in the width direction of the modular belt link, wherein the forwardly extending eyelet portions are offset relative to the rearwardly extending eyelet portions so that when two modular conveyor belt links are pushed together, the eyelet portions on one link will engage between the eyelet portions on the other modular belt link, and wherein holes are arranged transversely in each eyelet portion so that When the eyelet portions of two adjacent modular conveyor belt links cooperate with each other, the holes will overlap, thereby forming a through hole from one side of the conveyor belt to the opposite side, characterized in that a reinforcement structure is embedded in the material of the modular conveyor belt link between the load-bearing surface and the underside, and wherein the reinforcement structure extends into the eyelet portion, wherein the reinforcement structure is made of a material different from the material of the modular belt link, and wherein the transverse hole in the eyelet portion has a transverse center axis parallel to the load-bearing surface, and wherein the reinforcement structure in the eyelet portion extends below the center axis of the hole, and at least the portion of the reinforcement structure extending below the center axis of the hole is provided with a hole.

[0013] The inventive construction, designed specifically for loads significantly less than those normally experienced by conveyor belts, incorporates a high degree of rigidity into the conveyor belt due to the reinforcement structures embedded in the material of the modular conveyor belt links. Specifically, when the reinforcement structures extend into the eyelets, there is an overlap between adjacent eyelets from adjacent modular belt links, allowing the reinforcement structures in the eyelets to pass through the connecting pins, thereby establishing a longitudinal reinforcement system. Furthermore, by being able to embed reinforcement structures as described in the inventive embodiments of the present invention, the overall construction height of the conveyor belt modules can be reduced, which can be a space-saving advantage in secondary conveyor belt constructions. Prior art solutions using steel fishplates require a certain construction height to accommodate sufficient steel sheet material to transmit the forces generated in the conveyor belt. However, with the inventive reinforcement structures embedded and extending into all eyelets, the loads are distributed transversely across the entire belt, whereas with prior art arrangements, only a relatively small number of fishplates are built into the constrictions, resulting in each fishplate experiencing a concentrated load much higher than the load borne by the eyelets themselves.

[0014] In a further advantageous embodiment, the transverse hole in the eyelet portion has a transverse centre axis parallel to the bearing surface, and wherein the reinforcement structure extends between the bearing surface and the hole and below the centre axis of the hole.

[0015] In this embodiment, the reinforcement structure extends into the eyelet portion and passes through the transverse hole for inserting the connecting pin in such a way that a hook-shaped reinforcement structure is formed that is embedded inside the material of the modular conveyor belt chain link. Since the adjacent eyelet portions that mesh with each other between the eyelet portions of the first link will have the same structure, these hooks will together circumscribe most of the circumference of the connecting pin and thus provide a very efficient load transfer structure.

[0016] In another advantageous embodiment of the invention, at least the portion of the reinforcement structure extending below the central axis of the hole is provided with a hole. By providing the hole in the reinforcement structure, it is foreseen that during the molding process of the modular conveyor belt link, the liquid polymer material from which the modular conveyor belt link is manufactured will flow through the hole, thereby fully integrating the reinforcement structure into the modular conveyor belt link.

[0017] In another advantageous embodiment of the present invention, the reinforcement structure is a metal structure, wherein the metal can be steel, stainless steel, or spring steel. Alternatively, in another advantageous embodiment, the present invention provides that the reinforcement is a composite structure made of fiber-reinforced resin, wherein the fibers can be made of carbon, glass, ceramic, steel, or a polymer or a mixture of materials. All of these materials have in common that they have or can be designed to have very high tensile strength while retaining a certain degree of flexibility, allowing them to be integrated into the injection-molded thermoplastic body of the modular conveyor belt.

[0018] One of the challenges of molding reinforcements into thermoplastic materials is that, for example, POM (which is a widely used material for making these types of modular conveyor belt links) has a tendency to shrink by 3%-4%, while the reinforcement material has a much smaller shrinkage rate. This, of course, causes some internal tension issues in the molded modular conveyor belt link, but by properly designing the reinforcements, the reinforcement grid can absorb or accommodate this shrinkage without deforming the modular belt link.

[0019] In a further advantageous embodiment of the invention, the reinforcement has a material thickness measured perpendicularly to the load-bearing surface of between 0.3 mm and 4 mm, more preferably between 0.5 mm and 2 mm.

[0020] In order to ensure better adhesion between the reinforcement and the material from which the modular conveyor belt links are made, in another advantageous embodiment of the invention, the reinforcement can be surface-treated with a compound to achieve improved adhesion to the material from which the modular belt links are made. Alternatively, the surface of the reinforcement can be given a roughened surface, wherein the surface area of ​​the reinforcement is increased, so that the interface between the reinforcement and the material from which the modular conveyor belt links are made is greatly increased, thereby enabling the reinforcement to transfer forces to and from the material from which the modular conveyor belt links are made.

[0021] The present invention also relates to an endless conveyor belt assembled from a plurality of modular conveyor belt links as described above, wherein the eyelets of adjacent modular belt links partially overlap, thereby forming a through transverse hole, in which a connecting pin is inserted to hingedly connect the adjacent modular belt links, whereby the reinforcing structures in adjacent modular belt links overlap in the intended direction of travel of the endless conveyor belt.

[0022] In this way, a very strong, endless modular conveyor belt can be assembled. When the reinforcement structures overlap, the entire endless conveyor belt is provided with reinforcement, particularly for tension. Typically, when an endless conveyor belt is assembled from modular conveyor belt links manufactured from thermoplastic materials, for example during an injection molding process, the conveyor belt itself is relatively light compared to conveyor belts manufactured from steel. However, by incorporating the reinforcement structures into the injection-molded belt links, considerable strength is incorporated into the conveyor belt without adding significant weight to the belt itself.

[0023] This is further improved in another advantageous embodiment in which the connecting pin is made of the same material as the reinforcement structure or a material that is stronger than the reinforcement structure. Steel is the preferred material here, as it is a material that has been proven to be strong in tension, is relatively inexpensive, and is easy to process. However, other more exotic materials, such as reinforced plastic, can also be used. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematically shown is a top view of a modular conveyor belt link that can be assembled from a plurality of substantially identical modular belt links to construct a conveyor belt.

[0025] Figure 2a A cross section through a modular belt link is shown.

[0026] Figure 2b Shown is a view from the front of one or more laterally arranged modular belt links.

[0027] Figure 3 An embodiment is shown in which two modular belt conveyor links 1 , 1 ′ mesh with each other.

[0028] Figure 4a and Figure 4b An example of a reinforcement structure 30 according to the invention is shown.

[0029] Figure 5 An example of a surface structure on a reinforcement structure is shown.

[0030] Detailed Description of the Invention

[0031] Generally, in the drawings, the material from which the modular belt links are made is shown as transparent so that the reinforcement structure can be observed. In reality, the material from which the modular belt links are made is usually opaque.

[0032] exist Figure 1 , a top view of a modular conveyor belt link is schematically shown, which can be assembled with a plurality of substantially identical modular conveyor belt links to construct a conveyor belt. The modular conveyor belt link 1 has a load-bearing surface 10 and an underside 12 (see FIG2 ). A thickness of material exists between the load-bearing surface 10 and the underside 12; however, for construction purposes, various voids, cavities, etc. may be provided, particularly in the underside, to both reduce weight and allow a sprocket to engage the underside 12 of the modular belt link 1, thereby propelling the conveyor belt.

[0033] The modular belt link 1 has a main body 14 extending in the width direction of the modular belt link 1 , and wherein a plurality of eyelet portions 16 , 18 extend in forward and rearward directions relative to the main body portion 14 .

[0034] In this regard, "forward" and "rearward" should be interpreted as the intended direction of travel of the conveyor belt.

[0035] exist Figure 1 The conveyor belt modules shown in FIG can travel in either direction, but for purposes of description, one direction or the other has been selected as the forward direction and the rearward direction. The eyelet portions 16, 18 are spaced apart in the width direction (transversely) such that adjacent eyelet portions are separated by an opening 20. In addition, as shown Figure 1 As shown in FIG, the eyelet portions along one edge 16 are offset relative to the eyelet portion 18 and the opposing edge of the modular belt link 1. In this manner, when two identical modular belt links 1 are pushed together, the eyelet portion 16 on one edge will fit into the opening 20 between the eyelet portion 18 and the opposing side, and thus the modular belt link 1 can interengage with the overlapping eyelet portions.

[0036] In addition, if Figure 2a As shown in FIG, the holes 22 are arranged transversely in the eyelet portion, as also shown in FIG. Figure 1When two adjacent substantially identical modular belt links are engaged with each other as described above, the transverse holes 22 will overlap, thereby allowing the hinge pin to be inserted transversely, thereby hingedly connecting the adjacent modular belt links.

[0037] Figure 2a A cross section through a modular conveyor belt link is shown, for example as described above with reference to Figure 1 As described, the reinforcing structure 30 is embedded in the material of the modular conveyor belt link 1 between the bearing surface 10 and the underside 12. Figure 2a It can be clearly seen that the reinforcement structure 30 extends into the eyelet portions 16 , 18 and, in this particular embodiment, extends over the hole 22 and further curves with the eyelet portions below the central axis 24 of the hole 22 .

[0038] In this embodiment, the hole 22 is positioned closer to the load-bearing surface than to the underside. Furthermore, the hole is shown as a circular aperture 22, but depending on the intended use of the conveyor belt module, the hole may be generally oblong. The size and design of the hole are not critical to the present invention; however, it is important that the reinforcement structure 30 extends into the hole and, in the preferred embodiment, extends downwardly below the central axis 24 of the hole.

[0039] exist Figure 2b In the embodiment, identical or similar modular belt links are arranged transversely. It can be seen that the eyelet portions 16 along one edge are arranged at a transverse distance from each other, as are the eyelet portions 18 along the other edge. This allows adjacent modular belt links to be staggered. Furthermore, the reinforcement structure 30 is shown curved into the eyelet portions 16, 18. It can also be seen that a hole 40 is provided near the distal end of the reinforcement structure. This hole 40 allows the material used to make the modular belt link to flow through it, thereby securing the reinforcement structure. This securing helps activate the reinforcement structure when the modular belt link is subjected to tension.

[0040] exist Figure 3 , an embodiment is shown in which two modular belt conveyor links 1, 1' are intermeshed so that the transverse holes 22' overlap and form a through-hole 22'. To connect adjacent modular belt links 30, 30', a hinge pin (not shown) can be inserted into the overlapping through-holes 22'. Due to the configuration of the reinforcement structures 30, 30' (wherein the reinforcement structures extend into the eyelet portions 16, 18 and extend below the central axis 24 of the eyelet portions (and thus pass through the center of the hinge pin, not shown)), horizontal tension in the belt is transferred to the reinforcement structures 30, 30' due to the fact that the reinforcement structures 30, 30' extend below the central axis of the hole 22.

[0041] Figure 4a and Figure 4b An example of a reinforcement structure 30 according to the present invention is shown. The reinforcement structure 30 has a central section 32 that is embedded in the body of the modular conveyor belt link. A plurality of fingers 34, 36 extend bidirectionally from the central section 32. These fingers 34, 36 are shown in FIG. 2 and FIG. Figure 3 The embedding in the eyelet portion is such that the distance between adjacent fingers 34 and 36 is at least equivalent to the distance of the opening 20 in the finished modular belt link. Naturally, the embedded reinforcement structure 30 will be covered by a molded material, preferably a thermoplastic injection molded material, and likewise, the fingers 34, 36 embedded in the eyelet portion will also be covered by the injection molded material.

[0042] In this embodiment, holes 40 are provided near the distal ends 38 of the fingers. The holes 40 are provided so that the injection molded material can completely surround the reinforcing structure so that the injection molded material of the eyelet portion will have an intimate contact and stress-transmitting connection with the fingers 34, 36. In this way, they will be able to better transfer loads through the conveyor belt, as described above with reference to Figure 3 As stated.

[0043] Additional or additional holes 42 may be provided in the reinforcement structure to allow for better and more secure contact between the material from which the modular belt links are made and the reinforcement structure. When the reinforcement structure is in the form of a mesh, this facilitates excellent contact and integration. However, in some production situations, particularly during the injection molding process, correctly arranging the mesh in the mold can be challenging.

[0044] In some embodiments, it may be advantageous to provide the reinforcement structure with a surface treatment to improve the connection between the injection molded material and the reinforcement structure. To this end, various surface treatments may be applied.

[0045] exist Figure 5 An example of such a surface structure is shown in FIG. Figure 5 , at least four different types of surface treatments are shown. This does not mean that the modular belt links should be provided with all four of the five treatments, but rather that these treatments are merely examples of treatments that may be applied to the reinforcement structure. Within the reinforcement structure, an area a is indicated where the surface has been roughened, for example by grinding with very coarse sandpaper or the like, in order to increase the roughness of the surface and simultaneously increase the surface area.

[0046] In the region b of the reinforcing structure 30 , the surface of the reinforcing structure 30 is provided with dimples or small, shallow indentations in order to also improve adhesion to the injection-molded material in which the reinforcing structure 30 is to be embedded.

[0047] In region C, the ridges and / or grooves are positioned perpendicular to the intended direction of travel so that the ridges and / or grooves will form a strong bond with the injection molded material to transfer any stresses / strains down the conveyor belt.

[0048] Finally, in region D, chemical etching is shown on the surface of the reinforcement structure 30. Similar to the other examples mentioned above, chemical etching will improve the roughness of the surface of the reinforcement structure 30 and may simultaneously improve the bonding affinity between the injection molded material from which the conveyor belt module is made and the material of the reinforcement structure 30.

[0049] In this regard, as already discussed above, it is contemplated that the reinforcement structure may be made of any suitable material, but as preferred materials, in particular steel, spring steel, tin metal, various composite materials such as, for example, carbon fiber reinforced resin or ceramic fiber reinforced resin are contemplated within the scope of the present invention. Furthermore, the reinforcement structure may be, for example, Figure 4a , but it may also be a mesh, or it may be woven, for example, from stainless steel wires. Likewise, it may be (loosely) woven or non-woven in a manner that allows the material of the modular belt link to integrate the reinforcement structure into the body of the modular belt link.

Claims

1. A modular conveyor belt link of the type for use in an endless conveyor belt assembled from a plurality of such modular conveyor belt links, wherein the endless conveyor belt has a load-bearing surface and an underside opposite the load-bearing surface, wherein the modular conveyor belt link has a body extending in a width direction of the modular belt link, and wherein a plurality of eyelet portions extend forwardly and rearwardly from the body, the eyelet portions being spaced apart in the width direction of the modular belt link, wherein the forwardly extending eyelet portions are offset relative to the rearwardly extending eyelet portions so that when two modular conveyor belt links are pushed together, the eyelet portions on one link will engage between the eyelet portions on the other modular belt link, and wherein holes are arranged transversely in each eyelet portion so that when the eyelet portions of two adjacent modular conveyor belt links engage with each other, the holes will overlap to form a through hole from one side of the conveyor belt to an opposite side, It is characterized by: A reinforcement structure is embedded in the material of the modular conveyor belt link between the load-bearing surface and the underside, and wherein the reinforcement structure extends into the eyelet portion, wherein the reinforcement structure is made of a material different from the material of the modular belt link, and wherein the transverse hole in the eyelet portion has a transverse center axis parallel to the load-bearing surface, and wherein the reinforcement structure in the eyelet portion extends below the center axis of the hole, and at least the portion of the reinforcement structure extending below the center axis of the hole is provided with a hole.

2. The modular conveyor belt link according to claim 1, wherein: The modular belt links are injection molded from a thermoplastic material.

3. A modular conveyor belt link according to any one of claims 1 or 2, wherein: The reinforcement structure is a metal structure, wherein the metal can be steel, stainless steel, or spring steel.

4. A modular conveyor belt link according to any one of claims 1 or 2, wherein: The reinforcement structure is a composite structure made of fiber reinforced resin, wherein the fibers can be made of carbon, glass, ceramic, steel or a polymer or a mixture of materials.

5. A modular conveyor belt link according to any one of claims 3 or 4, wherein: The reinforcement structure has a material thickness measured perpendicularly to the load-bearing surface of between 0.3 mm and 4 mm, more preferably between 0.5 mm and 2 mm.

6. A modular conveyor belt link according to any one of claims 1 to 5, wherein: The reinforcing structure is surface treated with a compound in order to obtain improved adhesion to the material of the modular belt links.

7. A modular conveyor belt link according to any one of claims 1 to 5, wherein: The surface of the reinforcement structure is provided with a rough surface.

8. A modular conveyor belt link according to any one of claims 1 to 5, wherein: The reinforcement structure is provided with holes, or the reinforcement structure is a mesh, or the reinforcement structure is a knitted, woven or non-woven structure.

9. An endless conveyor belt assembled from a plurality of modular conveyor belt links according to any one of claims 1 to 8, wherein: The eyelets of adjacent modular belt links partially overlap to form a through transverse hole into which a connecting pin is inserted to hingedly connect adjacent modular belt links, whereby the reinforcing structures in adjacent modular belt links overlap in the intended direction of travel of the endless conveyor belt.

10. The endless conveyor belt according to claim 9, wherein: The connecting pin is made of the same material as the reinforcing structure or a material stronger than the reinforcing structure.

Images