Belt conveyor with free-running support rollers and driving sections

Abstract

A simple mechanical belt conveyor (12) for generating a predetermined transport distance (T) between a first conveyed item (46) and a second conveyed item (46) along a transport direction (TR, L) of the belt conveyor (12) is disclosed; wherein the belt conveyor (12) has a conveyor belt (24) which is configured for endless circulation and which is formed by links (30) interconnected in an articulated manner; wherein the links (30) have a multiplicity of first links (32), each of these having at least one free-running roller (40) which has a first coefficient of friction (µRoll); wherein contact regions between the free-running rollers (40) and the conveyed items (46) define a transport surface (TF) on which the conveyed items (46) to be transported lie on the belt conveyor (12) during transport; wherein the links (30) moreover have at least one second link (34) which has a driving section (36) which is arranged in the transport surface (TF) and has a second coefficient of friction (µHaft and / or µGleit) greater than the first coefficient of friction; wherein each of the second links (34) is positioned with respect to the conveyor belt (24) in such a way that the first and second conveyed items (46) are driven (only) by the respective driving section (36) at the predetermined transport distance (T), while the conveyor belt (24) is moved (continuously) through under the first and second conveyed items (46), and while undersides of the first and second conveyed items (46) are at least partially in contact with the moving conveyor belt (24).

Description

[0001] Belt conveyor with free-running rollers and carrier sections

[0002] The present disclosure relates to a (roller-accumulating) belt conveyor configured to set predetermined distances between conveyed goods in a flow of goods, wherein the belt conveyor has free-running support rollers on which the conveyed goods rest. Furthermore, the disclosure relates to a conveyor system comprising a corresponding belt conveyor.

[0003] Conveyor systems are known which are used to separate bundles which are initially provided in the form of a single pallet layer. For this purpose, several conveyor modules are arranged in a cascade-like manner, one behind the other and adjacent to one another. The modules are operated at different speeds, with the downstream modules preferably operating at a higher speed than the directly adjacent upstream modules. In this way, gaps parallel to the conveying direction can be created between individual rows of bundles in the pallet layer. To further separate the bundles in the already staggered rows, adjacent modules are aligned differently (e.g. by a 90° curve). In addition to classic belt conveyors, conveyor modules are also used which comprise endlessly circulating conveyor belts which in turn are formed from a large number of links which are connected to one another by hinges.Each of the links further includes at least one free-running idler roller that extends vertically beyond a base body of the link to define a transport surface on which the containers rest. These idler rollers can be driven in a targeted manner, for example, by applying a specific force from below to move the containers in a different direction in addition to the actual movement of the belt. A corresponding conventional conveyor system is available online at www.intralox.com under the product "ARB Pallet Layer Discrambler S400."

[0004] An alternative layer separation system is offered, for example, under the name "celluveyor DEPAL".

[0005] A basic requirement for separation and safe transport is that the floor surfaces of the conveyed goods have a flat surface. This requirement is not always met, especially when the conveyed goods (e.g., a six-pack of PET bottles) are wrapped in a PVC protective film.

[0006] Furthermore, existing systems often require the use of a camera system for product and position detection in order to specifically target individual containers within the pallet layer. This results in significant control effort and high demands on the containers themselves. For example, the containers must be clearly visible so that they and their position can be identified using image processing.

[0007] The document DE 101 46 981 A1 relates to an accumulating conveyor with a roller chain onto which support pieces can be attached in order to enable the material to be transferred without slippage.

[0008] It is therefore an object of the present disclosure to provide a conveyor and a conveyor system that increases the range of products to be separated, improves the independence from product properties and minimizes control effort.

[0009] This object is achieved by a belt conveyor for generating a predetermined transport distance between a first conveyed item and a second conveyed item, which are preferably provided without a distance therebetween in a conveyed item flow, along a (main) transport direction of the belt conveyor, wherein the belt conveyor has a conveyor belt which is designed for endless circulation and which is formed from links which are connected to one another in an articulated manner, wherein the links have a plurality of first links, each of which has a free-running roller (in the transport direction) which has a first (goods-specific) rolling friction coefficient, wherein contact areas (point, line or surface) between the free-running rollers and the conveyed items define a (substantially flat) transport surface on which the goods to be transported rest during transport on the belt conveyor, wherein the links further have at least one second link,which has a driving section arranged in the transport surface and which has a second (adhesive and / or sliding) friction coefficient that is greater than the first rolling friction coefficient, wherein each of the second members is positioned with respect to the conveyor belt such that the first and second conveyed goods are carried, in particular only, by the respective driving section at the predetermined transport distance, while the conveyor belt is moved (continuously) beneath the first and second conveyed goods and while undersides of the first and second conveyed goods are (successively in time) at least partially in contact with the moving conveyor belt.

[0010] With this belt conveyor, distances between conveyed goods in the transport direction can be created purely mechanically, without the use of camera systems, additional actuators, or complex control algorithms. The conveyor belt of the belt conveyor is provided with areas that result in higher frictional resistance between the conveyed goods and the conveyor belt. These areas are formed by the carry sections. The carry sections represent special areas of the conveyor belt that carry the conveyed goods compared to the other areas. The other areas slide and / or roll underneath the conveyed goods without carrying the goods with them. Thus, the (mechanical) distribution and arrangement of the carry sections alone can cause conveyed goods to be separated from a stream in which the conveyed goods are arranged without any distance from one another.

[0011] Preferably, each of the links has an identical base body which extends substantially perpendicular to the transport direction of the belt conveyor during transport, wherein the free-running rollers are preferably mounted in parallel rows perpendicular to the transport direction on the base bodies of the first links.

[0012] If all links have an identical base body, the drive sections can be easily repositioned, especially if the links themselves need to be replaced for this purpose. In other words, this means that the conveyor belt is formed from identically shaped base elements that differ in their drive characteristics. This simplifies the disassembly and reassembly of the links to form the conveyor belt.

[0013] In particular, the at least one second link is designed to be roller-free, so that its driving section projects into or beyond the transport surface instead of the at least one free-running roller of the first links, in particular with a friction element.

[0014] Alternatively, each of the links has the at least one free-running roller, wherein the driving section of the at least one second link is realized by the respective at least one free-running roller, the freewheeling of which can be inhibited or locked.

[0015] There are therefore two types of second links. The first type is visually indistinguishable from normal links (with normally free-running rollers), in that its normally free-running rollers can be selectively blocked or locked. If all links of the conveyor belt are second links with blockable or lockable rollers, reconfiguration of the carrier sections (and thus the desired spacing) is simplified by selectively blocking or locking the rollers of the required links. In this case, replacing links is not necessary.

[0016] Otherwise, the conveyor belt must be disassembled and the secondary links repositioned, as is the case when the drive sections are not implemented by the normally free-running rollers. The drive sections can be implemented, for example, by (rigid) friction elements. The friction elements are easily distinguishable for a technician visually from the primary links with rollers. The corresponding secondary links are easier to locate visually, which simplifies maintenance.

[0017] The relative positioning of these second links can be more easily verified visually. This makes commissioning errors, i.e., errors in the positioning of the second links within the conveyor belt, easier to locate and correct.

[0018] In a further alternative, all links are identically designed, wherein the driving section of the at least one second link is realized by a separate driving element which covers the at least one free-running roller of the respective second link in such a way that the corresponding driving element is in contact with one of the first and second conveyed goods during transport instead of the at least one free-running roller of the respective second link.

[0019] The carrier element is provided separately and can be positioned on any of the first links with free-running rollers of the entire belt, thus transforming them into second links. Here, too, the position of the carrier section is visually recognizable.

[0020] Furthermore, the carrier elements can be easily repositioned by manually removing them and reinstalling them at a different location, e.g., by attaching the carrier element to one or more other free-running rollers of the first links. The length of the carrier section (in the width direction of the conveyor) can also be easily configured by cutting the carrier element (e.g., as a rubber profile from a roller) to size and mounting it on the first links with rollers.

[0021] Preferably, the driving element is fixed in a form-fitting and releasable manner on at least one of the free-running rollers of the respective second member.

[0022] The positive locking mechanism supports easy assembly and disassembly of the carrier element. The carrier element is reusable and visually identifiable. A single free-running roller is sufficient to install the carrier element, especially in a captive manner.

[0023] In this design, the (rolling) friction coefficient or coefficient of friction of the rolling freewheel is generally replaced by the (adhesion and / or sliding) friction coefficient of the material of the carrier element. Rubber, plastics, and metals are examples of suitable materials for the carrier element. Chrome-plated steel has proven to be superior to other materials due to its significantly better wear resistance. Plain stainless steel would also be suitable.

[0024] Alternatively, the driving element can be releasably attached to a base body of the respective second link.

[0025] Instead of attaching the carrier element to the roller, it can also be attached to the base body of the corresponding link, for example, with a screw. In this case, too, the carrier element can be easily repositioned by unscrewing it from the original second link and screwing it onto another first link, which then becomes the second link.

[0026] Furthermore, the object is achieved by a conveyor system comprising: a feed conveyor, which is preferably an accumulating conveyor with or without free-running support rollers; a discharge conveyor; and a belt conveyor of the type described above, which is arranged in a transport direction between the feed conveyor and the discharge conveyor; wherein the feed conveyor and the discharge conveyor each adjoin the belt conveyor in the transport direction.

[0027] Preferably, the belt conveyor is operated at a first, in particular continuous, speed. The feed conveyor is operated at a second speed that is less than or equal to the first speed. The discharge conveyor is operated at a third speed that corresponds to the first speed.

[0028] This speed distribution ensures that the materials are safely removed from the infeed conveyor and transferred from the belt conveyor to the outfeed conveyor without any change in distance.

[0029] Furthermore, it is advantageous if the feed conveyor and the discharge conveyor are oriented horizontally and if the belt conveyor is oriented in the transport direction with an inclination angle a which is preferably in a range of 2 degrees to 30 degrees.

[0030] The inclined belt conveyor ensures that the free-running rollers of the links pass beneath the conveyed material. Since the continuous belt conveyor pushes the material forward with a corresponding rolling friction force due to rolling friction between the rollers and the underside of the material, the downward force caused by the inclined plane ensures that the material is not dragged along. The material is only dragged along if the drag section engages beneath the material, which creates greater frictional resistance.

[0031] In this way, it is possible for the feed conveyor to exert a certain back pressure on the material to be conveyed, which is provided in the transition area between the feed conveyor and the belt conveyor, without having to provide mechanical stops to hold back the material being conveyed.

[0032] In particular, the feed conveyor is designed and arranged to provide the first and second conveyed goods one after the other at its downstream end in such a way that the free-running rollers of the first links of the belt conveyor are permanently in contact with at least a downstream end section of an underside of the conveyed goods(s) provided.

[0033] Furthermore, it is preferred if the belt conveyor is permanently operated at a preferably constant speed.

[0034] This measure reduces control effort to zero. A camera system for separating is also not required, nor is it required for setting a desired distance between adjacent conveyed items.

[0035] The belt conveyor can be used as a separation conveyor, fusion conveyor or pallet layer separation device.

[0036] The belt conveyor is preferably designed with multiple tracks.

[0037] In the case of a multi-track design, the belt conveyor can be used in particular as a fusion conveyor to merge several conveyor streams without collision.

[0038] It is understood that the features mentioned above and those to be explained below are conceivable not only in isolation but also in combinations without departing from the scope of the disclosure.

[0039] Embodiments of the disclosure are illustrated in the following drawings and are described in more detail with reference to them.

[0040] Fig. 1 shows a block diagram of a conveyor system.

[0041] Fig. 2 shows a block diagram of a belt conveyor. Fig. 3 shows a perspective view of a conventional belt conveyor with articulated links.

[0042] Fig. 4 shows a perspective view of an isolated member of the belt conveyor of Fig. 3.

[0043] Fig. 5 shows a side view of a conveyor system.

[0044] Fig. 6 shows a side view (Fig. 6A) and a top view (Fig. 6B) of a single-track conveyor system.

[0045] Fig. 7 shows a side view of a second link.

[0046] Fig. 8 shows a side view of a slightly modified link, which is basically constructed like the link in Fig. 7.

[0047] Fig. 9 shows a side view of a further modified link.

[0048] Fig. 10 shows a side view (Fig. 10A) of a conveyor system analogous to the conveyor systems of Figs. 5 and 6, and a top view (Fig. 10B) of the same conveyor system.

[0049] Fig. 11 shows a plan view of another embodiment of a conveyor system used as a pallet layer separating device.

[0050] Fig. 12 shows a side view of a conveyor belt with second links formed by friction elements.

[0051] Fig. 13 shows a side view of a conveyor belt with links, each having two support rollers arranged one behind the other in the longitudinal direction, with second links being provided with separate drive elements. Fig. 14 shows a side view of a conveyor belt with links, each having two support rollers arranged one behind the other in the longitudinal direction, with second links being provided with other separate drive elements.

[0052] Fig. 15 shows a side view of a conveyor belt with links, each having a support roller in the longitudinal direction, wherein second links are provided with separate driving elements.

[0053] Fig. 16 shows a side view of a conveyor belt with links, each having two support rollers one behind the other in the longitudinal direction, the rollers being locked by second links.

[0054] The equipment described below can be used either in distribution centers or in the receiving areas of production centers. The equipment is primarily used for order picking in intralogistics.

[0055] Fig. 1 shows a block diagram of a conveyor system 10. The conveyor system 10 includes a belt conveyor 12. The conveyor system 10 may further include an infeed conveyor 14, a discharge conveyor 16, and / or a material flow controller (MFC) 18. The material flow controller 18 is communicatively connected to the conveyors 12, 14, and 16 via fixed lines and / or wirelessly (not shown).

[0056] The belt conveyor 12 can be operated, for example, as a separation conveyor 20 or as a fusion conveyor 22, as will be described in more detail below with reference to Figs. 6 and 10.

[0057] Fig. 2 shows a block diagram of the belt conveyor 12 of Fig. 1. The belt conveyor 12 has a multi-link conveyor belt 24, a machine frame 26, and at least two deflection rollers 28. The conveyor belt 24 is formed from a plurality of links 30, which are preferably all constructed identically in their basic structure, as will be explained in more detail below. The links 30 are configured to be connected to one another along a longitudinal direction L. The links 30 are all articulated to form the belt 24. The belt 24 is preferably closed in itself in order to be guided in an endless circulation around the deflection rollers 28.

[0058] In particular, the conveyor belt 24 is formed from a plurality of links 32 of a first type, i.e., first links 32, and at least one link 34 of a second type, i.e., at least one second link 34. The conveyor belt 24 has one or more driving sections 36, which can be formed separately from the first links 32 and / or as an (integrated) part of the second links 34.

[0059] Each of the first links 32 has a base body 38 and at least one free-running (support) roller 40. A support roller supports conveyed goods 46 (see Fig. 5) during transport. Free-running means that the roller 40 is mounted on or in the base body 38 in a substantially torque-free manner.

[0060] Conventional link belt conveyors with accumulation function consist only of the first links 32, see Fig. 3.

[0061] Each of the second links 34 also has a base body 28, at least one driving section 36, and optionally one or more free-running (support) rollers 40. The base bodies 38 of the first and second links 32 and 34 are preferably identical, particularly with regard to their dimensions and joint connections, in order to be interchangeably connectable to one another.

[0062] If the driving section 36 is implemented by a separately provided driving element 48, a first link 32 can be converted into a second link 34 by combining it with the separately provided driving element 48. Alternatively, the driving section 36 can be formed as an integral part of the second link 34, for example by changing the frictional resistance that the roller 40 exerts on a conveyed item 46 by locking the normally free-running roller 40 or by making the normally free-running roller 40 more difficult to rotate. As long as the roller 40 is free-running, its frictional resistance is caused solely by rolling friction. If the roller 40 is more difficult to rotate, the (relatively higher) frictional resistance is caused by a combination of sliding and rolling friction. If the roller 40 is locked, i.e. can no longer rotate, the frictional resistance is caused by the (even higher) static friction.

[0063] Fig. 3 shows a partial perspective view of a conventional, exemplary, multi-link, endlessly circulating belt conveyor 12, the links 30 of which have free-running (support) rollers 40 in order to implement an accumulation function. The exemplary single-track belt conveyor 12 of Fig. 3 is disclosed in the document EP 2 334 667 B1, to which reference is made here. The belt conveyor 12 of Fig. 3 can be used to implement the present invention, for example by mounting separately provided carrier elements 48 on the links 30, as shown, for example, in Figs. 7 and 8. The basic structure of a belt conveyor 24 will be explained below using the example of Figs. 3 and 4, with modifications of the embodiments specifically shown in Figs. 3 and 4 being discussed at the same time, which are not shown but could nevertheless be used to implement the present invention.

[0064] Basically, the links 30 of the conveyor belt 24 are pivotally connected to one another, with corresponding pivot axes 42 extending transversely in a transverse direction Q, in particular perpendicularly, to a longitudinal direction L of the belt 24. The links 30 are pivotally connected to one another via pivot pins 44 (see Fig. 4), which extend in the transverse direction Q. The longitudinal direction L is oriented parallel to the transport direction TR of the belt conveyor 12. The transverse direction Q is oriented perpendicularly to the longitudinal direction L. In the example of Fig. 3, the links 30 comprise only first links 32.

[0065] In the invention, the conveyor belt 24 is formed from several link types and has at least one second link 34. Regardless of the number of link types used, the links 30 preferably each have an identically shaped base body 38, which simplifies assembly of the belt 24 and replacement of individual links 30. This means that the first and second links 32 and 34 preferably have the same base body 38. The rollers 40 are freely mounted in the base body 38. It is understood that the links 30 could generally also be designed with fewer or more rollers 40, in particular with only a single roller 40 each. The second links 34 do not have to have any (supporting) roller 40 at all (cf. e.g.

[0066] Fig. 9).

[0067] Fig. 4 shows a perspective view of a single, unconnected link 30 of Fig. 3, which has, by way of example, twenty-two rollers 40. The rollers 40 are arranged, for example, in two rows R1 and R2 of eleven rollers 40 each, parallel to one another and parallel to the transverse direction Q (width direction of the conveyor belt 24). The rollers 40 are freely rotatable about roller axes 45. The roller axes 45 are oriented parallel to the transverse direction Q. The rollers 40 are free-running in the transport direction TR, ie, they are mounted essentially torque-free.

[0068] The roller axes 45 can have axial play, so that a gap width, i.e., a clear distance, between the rollers 40 can be variable in the longitudinal direction L. The rows R1 and R2 of Fig. 4 are spaced apart from one another in the longitudinal direction L of the belt 24, i.e., the rows R1 and R2 define a gap between them in the longitudinal direction L. It is understood that the rows R1 and R2 could generally each be equipped with a different number of rollers 40. Furthermore, it is understood that more or fewer than two rows R can be provided.

[0069] In general, the rollers 40 are arranged along an upper side of the conveyor belt 24 to define a (flat) transport surface TF there. The transport surface TF is (in the mathematical ideal case) oriented tangentially to the rollers 40 and is defined by support points or areas where the rollers and the conveyed goods 46 (not shown here) touch. In practice, however, the transport surface TF is defined as a wave-shaped surface where the conveyed goods 46 to be transported and the rollers 40 touch one another. During transport, the conveyed goods 46 rest on the rollers 40.

[0070] The conveyed goods 46 can be accumulated on the belt conveyor 12 by moving an obstacle (e.g., a stop movable into the conveying path) above the rollers 40 transversely into a transport path, thus stopping the conveyed goods on the belt 24 so that the stopped conveyed goods 46 remain on the free-running, rotating rollers 40, even though and while the belt 24 continues to move. The accumulation can be resolved by moving the obstacle back out of the transport path, so that the conveyed goods 46 are again carried along by the conveyor belt 24 (by frictional rolling).

[0071] A jam situation is shown as an example at a downstream end of a feed conveyor 14 in the side view of Fig. 5. Fig. 5 shows a first embodiment of a conveyor system 10 designed according to Fig. 1.

[0072] The conveyor system 10 of Fig. 5 has (directly adjacent to one another downstream of the conveyor) a feed conveyor 14, a belt conveyor 12, and a discharge conveyor 16. The belt conveyor 12 has an endlessly circulating conveyor belt 24 according to Fig. 2. The feed conveyor 14 can be a conventional, endlessly circulating belt conveyor (with or without rollers), which thus, in comparison to Fig. 2, only has no carrier sections 36 - and thus no second links 34 - but otherwise can preferably be designed analogously to the belt conveyor 24 of Figs. 3 and 4. The discharge conveyor 16 is preferably a classic continuous conveyor, such as an (endlessly circulating) belt conveyor, a link chain conveyor (with, see Fig. 3, or without free-running rollers 40), or a roller conveyor consisting of discretely arranged rollers.

[0073] The feed conveyor 14 and the discharge conveyor 16 are oriented horizontally, for example, while the centrally arranged belt conveyor 12 preferably has an angle of inclination a relative to the horizontal which is in a range from 2° to 30°, preferably from 3° to 15° and particularly preferably from 3° to 10°.

[0074] The feed conveyor 14 is operated as an accumulating conveyor, preferably in an endlessly rotating manner. The conveyed goods 46-1 and 46-2 move downstream at a (constant) speed v1. The speed v1 corresponds to the (constant) speed at which the multi-element belt 24 of the feed conveyor 14 is permanently moved relative to the machine frame 26 of the feed conveyor. Despite the permanently moving belt 24, the conveyed goods 46-3 and 46-4 remain stationary, i.e., they have a speed of essentially zero, apart from smaller, possible oscillatory movements (back and forth) in practice, which are caused by the permanent (rolling friction) force transmission to these conveyed goods 46-3 and 46-4 due to the rolling friction between the rollers 40 and the undersides of the conveyed goods 46-3 and 46-4. It is understood that the feed conveyor 14 could also be designed without rollers 40, for example.In this case, the rollerless links 30 would transfer a force to accumulated conveyed goods 46 in a sliding frictional manner.

[0075] The frictional force transmission ensures a certain dynamic pressure in the transport direction TR, i.e. a force that actually drives the conveyed goods 46-3 and 46-4 permanently forward in the transport direction TR, i.e. from left to right in Fig. 5. The dynamic pressure or the corresponding force presses the conveyed goods 46-3 and 46-4 against each other and against the rising belt 24 of the centrally arranged belt conveyor 12. The front conveyed goods 46-4 protrudes slightly into the middle belt conveyor 12 with a section that is at the front in the transport direction, in particular until the downhill force of the conveyed goods 46-4 and the dynamic pressure cancel each other out. The downhill force represents the above-mentioned "obstacle" that causes the accumulation.

[0076] The degree of overlap between the conveyed material 46-4 and the belt conveyor 12 determines the location where the conveyed material 46-4 is picked up. The conveyed materials 46 are picked up in the area of ​​their leading edges.

[0077] The centrally arranged belt conveyor 12 of Fig. 5 is designed according to Fig. 2, i.e., it has, in particular, locally discretely distributed second links 34 with entrainment sections 36, which ensure that the conveyed goods 46-5 to 46-7 are entrained by the belt 24 of the belt conveyor 12 despite its free-running rollers 40. The entrainment sections 36 will be described in more detail with reference to Fig. 6.

[0078] The belt conveyor 12 of Fig. 5 is preferably operated continuously and in particular at a constant speed v2. The speed v2 can be identical to the speed v1. However, it is understood that the belt conveyor 12 can also be operated discretely and at other, higher or lower, speeds v2. Preferably, the speeds v1 and v2 are similar to prevent idling or clogging of the (single-track) feed conveyor 14.

[0079] The discharge conveyor 16 is operated at a speed v3, which is, in particular, constant and identical to the speed v2. The discharge conveyor 16 is operated synchronously with the belt conveyor 12. These measures ensure that the conveyed goods 46 are not displaced during the transition from the belt conveyor 12 to the discharge conveyor 16.

[0080] Fig. 6 shows a first application in which the system 10 of Fig. 1 is used with a single-track arrangement of conveyors 12, 14, and 16 according to Fig. 5. Fig. 6A shows the same side view as Fig. 5. Fig. 6B shows a top view of the system 10 of Fig. 6A. The conveyed goods 46-1 to 46-9 of Fig. 6 are in the same states as shown in Fig. 5. The conveyors 12, 14, and 16 of Fig. 6 form a track by being arranged directly one behind the other downstream. The belt conveyor 12 of Fig. 6 is used as a separating conveyor 20 (cf. Fig. 1) to create an arbitrarily adjustable distance, in the longitudinal direction L or in the transport direction TR, between the respective leading edges of the conveyed goods 46.

[0081] The top view of Fig. 6B illustrates the regularly distributed, grid-like arrangement of the free-running rollers 40 with respect to the belts 24 of the conveyors 12 and 14. In comparison to the feed conveyor 14, however, the belt 24 of the belt conveyor 12 has, in addition to the free-running rollers 40, a plurality of driving sections 36, which are, for example, simply designed as separate driving elements 48, which are plugged onto the rollers 40 at a desired distance relative to one another.

[0082] Fig. 6 shows, by way of example, three driving sections 36, each defined by, for example, two driving elements 48. It is understood that more or fewer driving sections 36 can be provided. In particular, only a single driving section 36 could be provided, which, as a result of the endless circulation, separates the conveyed goods 46-3 and 46-4 (also with a distance between them that depends on the length of the belt 24). In Fig. 6, the driving sections 36 are arranged at a predetermined distance or pitch T from one another in the transport direction TR. The distance T is defined, for example, between a front edge of one of the driving sections 36 and a front edge of an adjacent one of the driving sections 36. The distance T could also be defined between the front and rear edges of adjacent conveyed goods 46, in particular if the conveyed goods are all of the same size.The distance T is preferably selected such that directly consecutive, i.e., adjacent, conveyed goods 46 in the conveying flow have a conveying gap between them. Preferably, the distances T between adjacent carrier sections 36 in the transport direction TR are all the same.

[0083] It is understood that the belt conveyor 12 of Fig. 6 has more than three drive sections 36 in the longitudinal direction L, with the remaining sections being merely concealed, i.e., not visible. Only the upper run of the belt 24 is visible in Fig. 6. The number of drive sections 36 along the length of the belt 24 can be chosen arbitrarily. The number can also be one, although the distance T is still established due to the circulation of the belt 24.

[0084] In Fig. 6, the carrier sections 36 are designed as separate carrier elements 48, which can be (subsequently) attached to a conventional link belt accumulating roller conveyor, positioned as required for the application, and removed again. Alternatively or additionally, the carrier sections 36 could also be implemented by the links 30, in particular the rollers 40 of the first links 32 (see Fig. 2), by modifying their running characteristics, in particular the rolling resistance of the rollers 40, as will be explained in more detail below.

[0085] The carrier elements 48 of Fig. 6 are, by way of example, strip-shaped and are designed to cover six adjacent, free-running rollers 40 in the transverse direction Q and one roller 40 in the longitudinal direction L. It is understood that the length and width of the (separate) carrier elements 48 are selected depending on the application. "Application-dependent" means, in particular, depending on the dimensions of the conveyed goods 46 and / or depending on the desired spacing T. In Fig. 6, the rollers 40 are arranged in rows, evenly distributed across the entire width B of the belt conveyor 12. The carrier elements 48 cover selected rows of rollers 40, so that these rollers 40 are no longer part of the transport surface TF and also no longer come into contact with the undersides of the conveyed goods 46 to be transported. The carrier elements 48 are made of a material that has a higher coefficient of friction than the rollers 40.This means that the carrier elements 48 have a better grip than the freely rotating rollers 40 and thus transfer greater forces caused by friction to the conveyed goods 46.

[0086] Friction generally describes the inhibition of movement or resistance to movement. A distinction must be made between: static friction, in which the bodies in contact do not move relative to each other; sliding friction, in which the surfaces of the bodies move relative to each other; and rolling friction, in which one body rolls against the other.

[0087] Sliding friction occurs, for example, when a force is applied to one body against another, causing one body to slide relative to the other. Sliding friction forces arise because, viewed microscopically, the surfaces of materials are never completely smooth, but rather rough. This causes the molecules on the two surfaces to "hook up" with each other. This then manifests itself macroscopically as a (frictional) force acting opposite to the direction of movement. Sliding friction is lower than static friction. Rolling friction is lower than sliding friction. Under comparable conditions, rolling friction is considerably lower than sliding friction.

[0088] The frictional force is proportional to the weight or normal force of a body and is independent of the size of the contact surface.

[0089] The coefficient of friction, also called frictional resistance coefficient or friction number (symbol p or f), is a dimensionless proportionality factor that expresses the ratio of the corresponding frictional force (adhesive, sliding, or rolling friction force) to the contact force (normal force) between two bodies. The friction number p depends, particularly in the case of adhesive and sliding friction, on the surface structure or the material of the bodies. The rolling friction number depends not only on the material pairing of the contacting bodies but also on the geometry, in particular on the radius, of the rolling body. The friction number is always defined for specific material pairings (e.g. cardboard on plastic). For the sake of simplicity, the specific material pairing will not be listed below; the friction number always represents a standard conveyed item on the respective material of the carrier section 36.

[0090] Returning to Fig. 6, the carrier elements 48 therefore have a higher coefficient of friction than the (rotating) rollers 40 when they come into contact with the underside of the conveyed material 46-4. The resulting frictional resistance is sufficiently large to overcome the downhill force of the conveyed material 46-4 and thus to carry the conveyed material 46-4 along, as already illustrated for the conveyed materials 46-5 to 46-7. Although in Fig. 6 two carrier elements 48 are mounted one behind the other on two rows of rollers in the transport direction TR, one of the carrier elements 48 alone can be sufficient for the transport, since the frictional force is independent of the area, as already explained above, provided that an equal normal force acts between the conveyed material 46 and the carrier elements 48.

[0091] As soon as the conveyed goods 46-5 to 46-7 reach the downstream end of the middle belt conveyor 12, they are taken over by the discharge conveyor 16. The discharge conveyor 16 is preferably operated at the same speed as the belt conveyor 12 so as not to change the gaps set there between the conveyed goods 46. The length of the gaps is identical if the conveyed goods 46 are identically dimensioned (and aligned). It is understood that in the transition area between the conveyors 12 and 16, the length of the gaps can also be influenced by a suitable selection of the speed v3 of the discharge conveyor 16.

[0092] With reference to Figs. 7 and 8, different designs of separately provided carrier sections 36, i.e. designs of carrier elements 48, are described below, which can be used instead of or in addition to the carrier elements 48 of Fig. 6. Fig. 7 shows a side view of an individual (conventional) link 30 of a (conventional) conveyor belt 24 with free-running rollers 40 according to DE 10 2012 104 891 A1, to which reference is made here with regard to the structure of the corresponding conveyor belt 24, which consists exclusively of first links 32. Three parallel rows of free-running rollers 40 are mounted in the base body 38, which are spaced apart from one another in the longitudinal direction L and which, in the height direction H, usually define the transport surface TF on their upper side. The carrier element 48' of Fig. 7 is inserted into the link 30 from above, i.e.mounted detachably and securely, whereby the conventional first member 32 becomes a second member 34 according to the invention in the sense of Fig. 2.

[0093] The driving element 48' of Fig. 7 has a flat support section 50 and, for example, two finger-like engagement sections 52. The support section 50 and the engagement sections 52 are connected to one another and are preferably formed in one piece.

[0094] In the assembled state shown in Fig. 7, the support section 50 extends substantially horizontally, i.e., in the QL plane. A length of the support section 50 in the longitudinal direction L is selected such that the support section 50 covers all rollers 40 of the corresponding link 30. If the link has more or fewer rollers 40 in the longitudinal direction L, the support section 50 is configured to be correspondingly shorter or longer. The support section 50 preferably ends in the longitudinal direction L just outside the highest point of the roller 40, which usually comes into contact with the conveyed material 46 (not shown here). If the link 30 has only a single roller 40 in the longitudinal direction L, the support section 50 is correspondingly shorter in the longitudinal direction L than in Fig. 7. However, the support section 50 preferably does not protrude beyond the corresponding link 30 or its base body 38 in the longitudinal direction L in order to facilitate the deflection around the deflection rollers 28 (cf. Fig.2 and 6) and possibly get lost there.

[0095] The engagement sections 50 of Fig. 7 extend vertically, i.e., parallel to the height direction H, and preferably each have a thickened portion 54 at their lower, free ends, which is dimensioned larger in the longitudinal direction L than a clear distance between the rollers 40. At least the outer rollers 40 (in the longitudinal direction L) can be mounted with a certain axial play 56 in the base body 38 (or alternatively in a bearing attached to the base body 38). During assembly, the engagement sections 52, which are preferably rigid, force at least the outer rollers 40 outward in the longitudinal direction L to clear the way for the thickened portions 54 to move downward through the gaps between the rollers 40. As soon as the thickened portions 54 have passed these gap areas between the rollers 40, the rollers 40 automatically move back to their original normal positions. The rollers 40 themselves can be elastically deformable.The mounting of the rollers 40 can cause elastic restoring forces. The carrier element 48' is then securely fixed between the rollers 40 and can be repositioned at any time (in the longitudinal direction L and / or in the transverse direction Q), in particular to adapt the spacing T (see Fig. 6) to the specific application.

[0096] Fig. 8 shows the member 30 of Fig. 7, on which a modified driving element 48" is mounted. The driving element 48' of Fig. 7 and the driving element 48" of Fig. 8 differ essentially in the engagement sections 52.

[0097] The driving element 48" of Fig. 8 has only one engagement portion 52. The engagement portion 52 of Fig. 8 is elastic. The engagement portion 52 is claw-shaped and is designed to be positively inserted onto the central roller 40 from above. Finger-like portions of the engagement portion 52 of Fig. 8 are preferably round in side view in order to fit tightly around the roller 40.

[0098] In a further variant, which is not illustrated in Figs. 7 and 8, the driving elements 48 could also be designed such that they are detachably mounted on the base bodies 38 of the links 30 instead of on the free-running rollers 40. The base bodies 38 and driving elements 48 could, for example, be designed such that the driving elements 48 are screwed to the base bodies 38. Any other type of preferably detachable connection of the separately provided driving elements 48 to the links 30 is possible, with positive and non-positive connections being preferred over material-to-material connections. After exemplary second links 34 (cf. Fig.2) which convert a conventional conveyor belt 24 comprising first links 32 with free-running rollers 40 into a belt conveyor 12 according to the invention by mounting separately provided carrier elements 48 on the first links 32 to make them second links 34, further variants are described below in which the conveyor belt 24 is actually formed from different links 30.

[0099] The corresponding conveyor belts 24 are essentially formed from first links 32 of the type described above, whereas further second links 34 are provided which do not require additional driving elements 48, either by their rollers 40 being designed to produce a variable frictional resistance or by the rollers being replaced by friction elements 58, cf. Fig. 9.

[0100] These second links 34 are configured to replace the first links 32 in the articulated connection of the conveyor belt 24. In practice, this means that (locally) selected first links 32 are replaced by the second links 34, e.g., by removing the corresponding first links 32 from the belt 24 and replacing them with the second links 34, which are subsequently installed. In these cases, changing the (relative) location of the driving sections within the belt 24 is somewhat more difficult than in the embodiments of Figs. 7 and 8, because the "chain" must be dismantled and then reassembled. However, the desired functionality is achieved with the same effect.

[0101] Ideally, the second links 34 are configured essentially identically to the first links 32 in terms of external shape, in particular by having a compatible base body 38 and similarly arranged rollers 40. However, the rollers 40 can either be selectively locked or their rolling resistance can be variable. If the rollers 40 are selectively lockable, they can either rotate freely and are thus free-running, or their rotation can be blocked, e.g., by inserting a cotter pin from the outside so that they no longer rotate.In this case, the frictional resistance on the conveyed goods 46 changes from rolling friction to sliding friction, so that greater frictional forces are transferred from the rollers 40 to the (undersides of the) conveyed goods 46, while the conveyor belt 24 is continuously moved under the successively delivered conveyed goods 46, so that the undersides of the conveyed goods 46 are at least partially in contact with the moving conveyor belt 24 (one after the other in time), see, for example, the situation in Fig. 6.

[0102] Alternatively, the running or rotating properties of the rollers 40 could be selectively influenced in such a way that the rollers 40 rotate more sluggishly and thus cause greater rolling resistance. This can be achieved, for example, by using thicker axles which do not rotate or rotate more sluggishly in their displacements and on which the plain-bearing rollers 40 do not rotate or rotate more sluggishly.

[0103] Instead of influencing the rolling properties of the rollers 40, the at least one roller 40 can also be replaced by a static element, such as a friction element 58. This is schematically illustrated in Fig. 9, where the member 30 of Figs. 7 and 8 has been modified accordingly.

[0104] Fig. 10 illustrates an alternative application of the belt conveyor 12 of Fig. 1 in a conveyor system 10 which is exemplary almost identical to the conveyor system 10 of Fig.

[0105] 5 and 6. In contrast to the system 10 of Fig. 6, which has a single-track structure, the system 10 of Fig. 10 has two tracks SP1 and SP2 in the area of ​​the feed conveyor 14 and the belt conveyor 12, which are combined into a single track with a smaller overall width in the area of ​​the discharge conveyor 16. Fig. 10 illustrates an example in which the belt conveyor 12 assumes the function of a fusion conveyor 22 mentioned in Fig. 1.

[0106] Fig. 10A shows a side view and Fig. 10B shows a top view of the system 10 of Fig. 10. The belt conveyor 12 and the feed conveyor 14 are each formed with two tracks SP1 and SP2. The tracks SP1 and SP2 of the belt conveyor 12 can, for example, be provided alternately with driving sections 36. The driving sections 36-1 and 36-3 are arranged in the track SP1. The driving section 36-2 is arranged in the track SP2 of the belt conveyor 12. Instead of the belt conveyor 12, which is composed of two conveyor belts 24, which are arranged, for example, directly adjacent to one another in the transverse or width direction Q, a belt conveyor 12 with a single conveyor belt 24 that is twice as wide (not shown) can be used. The feeding of the conveyed goods 46 could also take place in a single track (with a conveyor means that is twice as wide) (not shown). The driving sections 36 are shown in Fig. 10 by way of example by the driving elements 48 as in Fig.6 trained.

[0107] The distances T between the driving sections 36-1 to 36-3 can be selected to be constant in the longitudinal direction L, as in Fig. 6. However, the driving sections 36-1 and 36-3 of the first track SP1 have a relative distance of 2T from one another. The driving section 36-2 of the second track SP2 is arranged - in the longitudinal direction L - centrally between the driving sections 36-1 and 36-2, but laterally offset from the driving sections 36-1 and 36-2 in the transverse direction Q. Thus, the side view of Fig. 10A shows the same picture as in Fig. 6A, although further conveyed goods 46-10 to 46-12 are present, forming a second conveying stream to be merged with the first conveying stream on the first track SP1.

[0108] The two tracks SP1 and SP2 are combined into a single track at the downstream end of the belt conveyor 12. The discharge conveyor 16 can again be implemented as a roller conveyor and can additionally have two guide elements 60 to converge the material flows from the input-side tracks SP1 and SP2 into a single track. The guide elements 60 are arranged vertically above the transport surface TF. The guide elements 60 can be implemented as plate-shaped elements, similar to guard rails. The guide surfaces of the guide elements 60 are oriented essentially vertically. The guide elements 60 can also be vertically oriented belt conveyors set at the same speed as the discharge conveyor in order to prevent the materials 46 or packages from shifting relative to one another due to friction on static guide elements, counter to the transport direction TR. In the top view of Fig.10B, the guides 60 are oriented downstream, preferably at the same angle, to the center of the transverse direction Q.

[0109] A further application of the belt conveyor 12 of Fig. 1 will be described below with reference to Fig. 11. The belt conveyor 12 can also be used to separate packages in a pallet layer, as schematically illustrated in Fig. 11. In this case, the packages represent the conveyed goods 46.

[0110] Fig. 11 shows a plan view of a belt conveyor 12 and a feed conveyor 14, which are part of a system 10. A discharge conveyor 16 with guide elements 60 is not shown, but can be connected downstream of the belt conveyor 12, as shown in Fig. 10. A pallet layer 62 of, preferably equally dimensioned, conveyed goods 46 is provided via the feed conveyor 14. The pallet layer 62 consists of, for example, twelve conveyed goods 46, of which the conveyed goods 46-1 to 46-3 have already been withdrawn, i.e., separated, from the conveyor belt 24 of the belt conveyor 12 at the desired distance T.

[0111] The (visible) driving sections 36-1 to 36-3 are distributed evenly across the width B of the conveyor belt 24 in the transverse direction Q and spaced apart by T in the longitudinal direction L. The belt 24 in turn has a plurality of (not shown) free-running rollers 40, to which driving elements 48 have been attached.

[0112] Thus, various applications of the belt conveyor 12 and various configurations of the carrier sections 36 have been described. It has been described that conventional accumulating roller conveyors with free-running (support) rollers can be subsequently converted into multi-element belt conveyors 12 according to the invention. The belt conveyor 12 creates desired spacings between the conveyed goods 46 using simple mechanical means and does not require expensive and complex additional systems such as cameras, actuators, and image processing and control software.

[0113] Figs. 12-16 illustrate side views of modifications of second links 34. Figs. 12-16 show only a partial view of the corresponding conveyor belts 24, which are composed of the first and second links 32 and 34, with the first link 32 shown on the left being shown in a deflection state. Fig. 12 shows rollerless second links 34 with friction elements 58, with the first links 32 each being provided with two rollers 40 (in the longitudinal direction L). The friction elements protrude vertically upward from the transport surface TF.

[0114] Fig. 13 shows a belt 24 formed from first links 32, each having two rollers 40, wherein a separate carrier element 48 is clipped between the rollers 40 of the middle links 30, so that these become second links 34. Here, too, the carrier elements 48 protrude vertically upward from the transport surface TF, which is defined by the rollers 40.

[0115] Fig. 14 shows the belt 24 of Fig. 13, wherein differently shaped carrier elements 48 are used, which are pulled (in the transverse direction Q) over both rollers 40 of the second links 34.

[0116] Fig. 15 shows three links 30 of a belt 24, each provided with a roller 40, wherein the driving elements 48 of the second links 34 are each clipped onto the corresponding roller 40.

[0117] Fig. 16 shows the belt 24 of Figs. 12 and 13, wherein a locking element 64 (removable) is placed between the rollers 40 of the second links 34, which locks the freewheel of the rollers 40. The locking elements 64 do not protrude into the transport surface TF.

[0118] List of reference symbols

[0119] 10 Conveyor system

[0120] 12 belt conveyors

[0121] 14 feed conveyors

[0122] 16 discharge conveyors

[0123] 18 material flow computers (M FR)

[0124] 20 separation conveyors

[0125] 22 Fusion conveyor 24 Conveyor belt

[0126] 26 Machine frame

[0127] 28 pulleys

[0128] 30 links

[0129] 32 1st members

[0130] 34 2nd members

[0131] 36 Takeaway section

[0132] 38 basic bodies

[0133] 40 rolls of the 1st and 2nd links

[0134] 42 Joint axis

[0135] 44 hinge pins

[0136] TF transport area

[0137] 45 roller axle

[0138] 46 Conveyed material

[0139] R (roller) row

[0140] 48 Driving element

[0141] 50 supporting sections

[0142] 52 intervention section

[0143] 54 Thickening

[0144] 58 friction elements

[0145] 60 guide elements

[0146] 62 pallet layers

[0147] 64 locking element

Claims

Claims: Belt conveyor (12) for generating a predetermined transport distance (T) between a first conveyed item (46) and a second conveyed item (46) along a transport direction (TR, L) of the belt conveyor (12); wherein the belt conveyor (12) has a conveyor belt (24) that is set up for endless rotation and that is formed from articulated links (30); wherein the links (30) have a plurality of first links (32), each having at least one free-running roller (40) that has a first coefficient of friction for the conveyed items (46); wherein contact areas between the free-running rollers (40) and the conveyed items (46) define a transport surface (TF) on which the conveyed items (46) to be transported rest during transport on the belt conveyor (12);wherein the links (30) further comprise at least a second link (34) which has a carrying section (36) which is arranged in the transport surface (TF) and which has a second coefficient of friction which is greater than the first coefficient of friction;wherein each of the second links (34) is positioned with respect to the conveyor belt (24) such that the first and second conveyed goods (46) are carried along by the respective carrying section (36) at the predetermined transport distance (T), while the conveyor belt (24) moves under the first and second conveyed goods (46) and while undersides of the first and second conveyed goods (46) are at least partially in contact with the moving conveyor belt (24). Belt conveyor (12) according to claim 1, wherein each of the links (30, 32, 34) has an identical base body (38) which extends substantially perpendicular to the transport direction (TR, L) of the belt conveyor (12) during transport, and wherein the free-running rollers (40) are preferably arranged in parallel rows; (R) are attached perpendicular to the transport direction (TR, L) to the base bodies (38) of the first links (32).

3. Belt conveyor (12) according to claim 2, wherein the at least one second member (34) is designed without rollers, so that its drive section (36) projects into or beyond the transport surface (TF) instead of the at least one free-running roller (40) of the first members (32), in particular with a friction element (58).

4. Belt conveyor (12) according to claim 1 or 2, wherein each of the links (30, 32, 34) has the at least one free-running roller (40), and wherein the drive section (36) of the at least one second link (34) is realized by the respective at least one free-running roller (40), the free-running of which can be locked or stopped.

5. Belt conveyor (12) according to claim 1 or 2, wherein the links (30, 32, 34) are all identically designed, and wherein the driving section (36) of the at least one second link (34) is realized by a separate driving element (48) which covers the at least one free-running roller (40) of the respective second link (34) in such a way that the corresponding driving element (48) is in contact with one of the first and second conveyed goods (46) during transport instead of the at least one free-running roller (40) of the respective second link (34).

6. Belt conveyor (12) according to claim 5, wherein the drive element (48) is fixed in a form-fitting manner on at least one of the free-running rollers (40) of the respective second link (34).

7. Belt conveyor (12) according to claim 6, wherein the driving element (48) is detachably attached to a base body (38) of the respective second member (34).

8. Conveyance system (10) with: a feed conveyor (14), which is preferably a chain conveyor with or without free-running support rollers (40); a discharge conveyor (16); and a belt conveyor (10) according to one of the preceding claims, which is arranged in a transport direction (TR) between the feed conveyor (14) and the discharge conveyor (16); wherein the feed conveyor (14) and the discharge conveyor (16) are each directly adjacent to the belt conveyor in the transport direction (TR).

9. Conveyor system (10) according to claim 8, wherein the belt conveyor (12) is operated at a first, preferably continuous, speed (v1), the feed conveyor (14) is operated at a second speed (v2) which is less than or equal to the first speed (v1), and the discharge conveyor (16) is operated at a third speed (v3) which corresponds to the first speed (v1).

10. Conveyor system (10) according to claim 8 or 9, wherein the feed conveyor (14) and the discharge conveyor (16) are horizontally oriented, and the belt conveyor (12) is oriented in the transport direction (TR) with an incline angle α which is preferably in a range of 2° to 30°.

11. Conveyor system (10) according to one of claims 8 to 10, wherein the feed conveyor (14) is set up and arranged to provide the first and second conveyed goods (46-3, 46-4) successively at its downstream end such that the free-running rollers (40) of the first links (32) of the belt conveyor (12) are permanently in contact with at least a downstream end section of an underside of the provided conveyed goods (46).

12. Conveyor system (10) according to one of claims 8 to 11, wherein the belt conveyor (12) is operated permanently at a preferably constant speed. Conveyor system (10) according to any one of claims 8 to 12, wherein the belt conveyor (12) is a separating conveyor (20), a fusion conveyor (22), or a pallet layer singulation device. Conveyor system (10) according to any one of claims 8 to 13, wherein the belt conveyor (12) is configured as a multi-lane conveyor.

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