Additively manufactured conveyor track for a vibratory conveyor

Abstract

The invention relates to a conveyor track (10) for a vibratory conveyor, which conveyor track is designed to guide an object (16) to be conveyed, during its movement, over a predetermined conveying path (S) along a transport direction (T), and at the same time to rotate the object (16) by a predetermined conveying angle, in particular by 180°, about a conveyor-track central axis (C) which extends parallel to the transport direction (T), wherein the conveyor track (10) comprises a guiding arrangement (12) having a plurality of guide rails (14) which wind around the conveyor-track central axis (C) along the conveying path (S) in accordance with the conveying angle, and wherein the conveyor track (10) is produced in one piece by an additive manufacturing process, for example by selective laser sintering or 3D printing, preferably from stainless steel.

Description

[0001] Additively manufactured conveyor track for a vibratory conveyor

[0002] Description

[0003] Vibratory conveyors are used in many industries, especially to provide small parts in the correct orientation for automated further processing.

[0004] In the medical and pharmaceutical sector, such vibratory feeders are used, for example, in the automatic sealing of pharmaceutical containers to automatically feed closure elements from a supply to a sealing device in the desired position, as disclosed, for example, in German patent applications DE 102014222127 A1 and DE 102020134792 A1. The closure elements are guided and moved along groove-shaped conveyor tracks by vibration.

[0005] The conveyor belts also form a buffer zone for the sealing elements, whereby the backflow that forms on the conveyor belts during operation ensures that even with fluctuations in the feed, there are always enough sealing elements available for a timed insertion process.

[0006] To ensure the desired purity and freedom from particles, vibratory conveyors, especially in the medical and pharmaceutical sector, are often supplied from above with a laminar flow (LF flow) of clean or sterile air.

[0007] To ensure that critical surfaces of the sealing elements—that is, the surfaces that will later be in contact with the interior of the container to be sealed—are supplied with clean air from above for as long as possible, the sealing elements are rotated 180° into the correct insertion position just before being placed in the containers. The two aforementioned publications describe a separate turning device at the distal end of the conveyor tracks for this purpose. However, practical experience has shown that the 180° rotation of the conveyed objects can also be achieved using appropriately shaped conveyor tracks, thus eliminating the need for the separate turning device.

[0008] An example of such a conventional conveyor system currently used in practice, with the features of the preamble of claim 1, is shown in Fig. 1 and is explained in more detail in the figure description.

[0009] The conveyor system of this type is designed to guide an object to be conveyed along a predetermined conveying path as it moves along a transport direction, rotating the object by a predetermined conveying angle, in particular by 180°, around a conveyor central axis that runs parallel to the conveying path, wherein the conveyor system has a guide arrangement with several guide rails that wind around the conveyor central axis along the conveying path according to the conveying angle.

[0010] Up to now, the guide rails have been bent by hand from individual metallic profile strips, tacked, welded and fixed at various points along the conveyor line in the desired position and orientation to each other using vertical retaining plates, whereby the retaining plates become an integral part of the conveyor line.

[0011] However, the well-known manual manufacturing process requires a significant investment of time and personnel, as well as considerable craftsmanship and experience.

[0012] Against this background, the object of the present invention is to improve the reproducibility and repeatability precision of the known guideway.

[0013] This problem is solved by a conveyor belt with the features of claim. According to the invention, it is provided that the conveyor belt is manufactured in one piece using an additive manufacturing process, for example by selective laser sintering, selective laser melting or 3D printing, preferably from stainless steel.

[0014] In this way, the shape and orientation of the guideways relative to each other are precisely defined beforehand, for example in a CAD model, and the conveyor track can be manufactured almost entirely by machine in significantly reduced time and with reduced overall costs. Reproducibility and repeatability are considerably increased, and comprehensive, automated process monitoring is possible.

[0015] Furthermore, the new manufacturing process opens up new possibilities for the geometric design of the conveyor track, which can be optimized with regard to mass and friction reduction, flow characteristics, and vibration behavior. In particular, dead spaces and turbulence during the LF flow from above can be minimized.

[0016] For example, each guide rail may have a teardrop shape in cross-section, with a single point designed to make contact with the object as it moves along the conveyor track. The section plane of the cross-sectional view is perpendicular to the conveyor track's central axis. A teardrop shape is defined as any cross-sectional shape that is rounded except for the single point, or has only rounded edges; for example, a shape that is essentially circular or elliptical except for the single point.

[0017] The teardrop-shaped cross-section ideally reduces the contact area between the guide rail and the conveyed object to line contact, thereby reducing friction between the object and the guide rail during transport and improving the flow characteristics of the conveyor track. The teardrop shape of the guide rails, which is rounded except for the tip, also improves the flow characteristics of the conveyor track when exposed to air.

[0018] In particular, horizontal surfaces in the conveyor track, on which dust and other particles or germs could settle during operation, can be largely or completely dispensed with.

[0019] When viewed in cross-section, the tips of the guide rails can always point inwards, towards the central axis of the guide track or towards the conveyed object, or at least always point in a direction that forms an angle of less than 45° with a line connecting the tip of the guide rail and the central axis of the guide track, preferably less than 30° (see Fig. 7).

[0020] The tips of the guide rails can each form an angle of about 70° to about 90°, preferably about 75° to about 85°, particularly preferably about 80°, in order to avoid a flat contact surface for the objects to be conveyed.

[0021] According to a preferred embodiment of the present invention, the guide arrangement comprises exactly three guide rails. This allows, in particular, the reliable guidance of closure elements that are cylindrically symmetrical and taper continuously or in steps from one end to the other along the axis of symmetry, and which are referred to here as "plugs". The conveyor track can therefore also be called a plug track.

[0022] In general, however, a wide variety of objects, such as syringe stoppers, crimp caps, screw caps, bottles, vials, syringes, plugs, capsules, lids, cartridges, and other containers, can be transported using the conveyor system according to the invention, and the shape and number of guide rails can be adapted to the specific object being transported. For example, it is also possible for the guide arrangement to comprise exactly four guide rails. To join the guide rails together in one piece during manufacturing using an additive process and thus define their relative position and orientation to one another, a suitable connection structure must be provided.

[0023] Preferably, the conveyor track further comprises at least one connecting rail that winds completely around the conveyor track's central axis and the guide arrangement at least once or, for example, at least twice, connecting the guide rails in one piece.

[0024] Preferably, the conveyor track comprises two connecting rails that wind in opposite directions at least once completely around the conveyor track's central axis and around the guide assembly, integrally connecting the guide rails. The two connecting rails form a cage for the guide rails within which the object is moved. Preferably, the connecting rails wind in opposite directions twice completely around the guide assembly.

[0025] Preferably, each connecting rail runs along an (imaginary) cylindrical shell whose cylinder axis coincides with the conveyor track's central axis, and the guide arrangement is housed inside this cylindrical shell.

[0026] The connecting rails can have the shape of a helix, but the slope of the connecting rails can also vary along the conveyor route.

[0027] For manufacturing reasons, it is advantageous if each of the connecting rails and each of the guide rails runs at an angle steeper than 45° to the conveyor's central axis at every point along the conveyor track. This ensures that the guide and connecting rails are self-supporting and self-supporting during additive manufacturing, eliminating the need for additional support structures that would unnecessarily increase the weight of the resulting structure or require manual removal after manufacturing, necessitating costly post-processing steps (grinding, polishing, etc.) to achieve the desired surface quality.

[0028] To improve the flow characteristics, the connecting rails preferably have a rounded, for example circular or oval, cross-section.

[0029] For mounting on a support structure through which the vibration movement of the vibratory conveyor is initiated, two support structures can be provided, arranged in or near opposite end regions of the conveying path. The support structure can, for example, be a base plate on which several conveyor tracks are preferably mounted side by side.

[0030] For example, a threaded hole can be provided in the underside of each support structure to screw the conveyor belt to the support structure.

[0031] For a stable connection in a conveyor system with two connecting rails winding in opposite directions around the central axis and guide arrangement, it can be provided that each of the two support structures is connected to the connecting rails at at least one intersection point of the two connecting rails.

[0032] In general, the supporting structures are preferably designed to avoid sharp corners and edges as well as horizontal surfaces.

[0033] To monitor the conveying movement, a sensor recess can be provided, particularly at one end of the conveying path, on one of the guide rails. During operation, a detection beam from a sensor, for example from below, can pass through this recess to detect when an object passes through it. From a manufacturing perspective, it is advantageous to have a support structure, preferably ring- or frame-shaped, at one end of the conveying path. This support structure integrally connects the guide rails and preferably also the connecting rails. The support structure has a flat bearing surface perpendicular to the central axis of the conveying path, upon which the conveying path rests and is supported during its manufacture.

[0034] To ensure controlled and desired vibration behavior of the conveyor track, it is preferably necessary to ensure that its lowest natural frequency is sufficiently far removed from the excitation frequency of the vibratory drive of the vibratory conveyor, approximately at least five or ten times the excitation frequency. With a typical excitation frequency of about 50 Hz, the conveyor track is therefore preferably designed such that its lowest natural frequency is at least 250 Hz, preferably at least 400 Hz, and particularly preferably at least 500 Hz.

[0035] Another advantage of the additive manufacturing process compared to the previous manual method is that the vibration behavior of the conveyor track can be determined in advance using simulation calculations and the shape of the conveyor track can be adjusted accordingly.

[0036] Furthermore, protection is also sought for a vibratory conveyor, particularly for stoppers or other objects with a cylindrical basic shape, preferably for medical or pharmaceutical applications, and especially preferably for use in a filling plant for pharmaceutical products. The conveyor comprises a support structure, particularly in the form of a base plate, and at least one conveyor track according to the invention, arranged on and attached to the support structure, as described in this application. Preferably, several conveyor tracks according to the invention are arranged side by side and parallel to each other on and attached to the support structure. In particular, the vibratory conveyor can also include a vibration drive coupled to the support structure in order to transmit a vibrational movement to the conveyor tracks via the support structure.According to another aspect, the problem of the invention mentioned in the introduction is also solved by a method for producing a one-piece conveyor track according to the invention in an additive manufacturing process according to the independent method claim.

[0037] The method according to the invention comprises the following steps:

[0038] Providing data, for example CAD data, that defines the shape of the conveyor path; building the conveyor path layer by layer along a build direction in an additive manufacturing process based on the provided data, in particular by selective laser melting or selective laser sintering, wherein the conveyor path's central axis preferably runs parallel to the build direction. The layer thickness can be, for example, 25 pm to 60 pm.

[0039] The assembly can be done using 3D printing with LPBF (Laser Powder Bed Fusion) with a closed powder circuit and a twin laser, which currently allows one track to be produced in 20 hours, and up to eight tracks simultaneously in 30 hours.

[0040] Stainless steel is particularly suitable as a material, preferably 1.4404.

[0041] After removing the conveyor belt from the substrate, also known as the substrate plate, one or more of the following post-processing steps can be carried out, depending on the requirements for the finished conveyor belt:

[0042] - Removal of any support structures that may be required on the supporting structures,

[0043] - Grinding of connection surfaces,

[0044] - Removal of powder material from cavities,

[0045] - Blasting of accessible surfaces (glass blasting / sandblasting / trolling)

[0046] - Mechanical manufacturing of threads on the support structures

[0047] - Chemical and / or mechanical pre-cleaning

[0048] - Chemical pickling according to VHC700 - Electrochemical polishing of the surface, preferably with a material removal rate of 10-15 µm

[0049] - Rinsing, passivation, final cleaning, drying.

[0050] Preferably, the conveyor is manufactured in such a way that an arrangement formed from the guide rails and the connecting rail or rails largely or completely supports and carries itself during manufacture.

[0051] This means that the connecting and guide rails are supported during manufacturing at most on the ring- or frame-like support structure of the conveyor track described above on a substructure.

[0052] However, for the conveyor belt support structures described above, the construction of suitable additional structures to support the support structures on the substructure may be necessary during manufacturing.

[0053] These additional structures must be removed in a post-processing step after additive manufacturing.

[0054] The present invention will now be explained in more detail with reference to some selected embodiments and comparative examples, which are illustrated in the accompanying figures.

[0055] Fig. 1 shows an example of a conveyor system known from the prior art in a perspective view.

[0056] Fig. 2 shows a perspective view of a first embodiment of a conveyor system according to the invention.

[0057] Fig. 3 shows the object of Fig. 2 in a top view.

[0058] Fig. 4 shows the object of Fig. 2 in a bottom view. Fig. 5 shows, in partial figures (a), (b) and (c), the object of Fig. 3 in a cross-sectional view for the section planes labeled AA, BB and CC in Fig. 3.

[0059] Fig. 6 shows the comparative example from Fig. 1, known from the prior art, in a cross-sectional view.

[0060] Fig. 7 shows the partial figure (a) from Fig. 5 in an enlarged view, with the object to be transported omitted.

[0061] Fig. 8 shows a top view of parts of a known vibratory conveyor with the conveying paths from Fig. 1.

[0062] Fig. 9 shows in a top view parts of an embodiment of a vibratory conveyor according to the invention with conveying tracks according to Fig. 2.

[0063] Fig. 10 shows a perspective view of more parts of the vibratory conveyor from Fig. 9.

[0064] Fig. 11 shows a flowchart of an embodiment of a method according to the invention for producing a conveyor belt.

[0065] Fig. 12 shows in simplified and schematic form a system for the production of a conveyor system according to the invention.

[0066] Identical or corresponding features in the figures for the various embodiments and comparative examples are identified by the same reference numerals. If a figure contains several similar elements, not all are necessarily provided with a reference numeral for the sake of clarity. Generally, only those features in a figure that are necessary or useful for explaining and understanding the respective figure are provided with a reference numeral. Unless otherwise specified or evident from the context, terms such as "top," "bottom," "horizontal," and "vertical" in this application refer to the usual arrangement of a conveyor track in a vibratory conveyor, wherein the transport direction is horizontal and the conveyor track is attached to the top of a support structure and is pressurized with air from above during operation.

[0067] Fig. 1 illustrates an example of the previously known construction of a conveyor track 10 for a vibratory conveyor, which has a guide arrangement 12 with three guide rails 14, which is designed to guide objects to be conveyed from a proximal end 10p to a distal end 10d of the conveyor track 10 along a transport direction T over a conveying distance S and to rotate the objects 16 by a conveying angle of 180° around a conveyor track central axis C (short: central axis).

[0068] In the conventional conveyor 10 shown in Fig. 1, the individual guide rails 1 are formed from angular and partially beveled profile strips made of metal, which are each bent by hand around the central axis C and are arranged in a series of upright retaining plates 11 positioned along the conveyor path S and fixed to these by welding in such a way that the position and orientation of the three guide rails 14 relative to each other along the conveyor path S always remains essentially the same, while the orientation of the entire guide arrangement 12 at the distal end 10d of the conveyor 10 is rotated by 180° around the central axis C relative to the orientation at the proximal end 10p.

[0069] The retaining plates 11, mounted on a support rail 13, are necessary to determine the alignment of the guide assembly 12 at defined points along the conveyor path S during the manual production of the conveyor track 10. For identification purposes, the retaining plates 11 are numbered consecutively from the proximal end 10p to the distal end 10d and designated 11.1 to 11.6. Manual production by cold forming is time-consuming and labor-intensive, requiring experience and skill, which negatively impacts the reproducibility and repeatability of the conveyor track.

[0070] A conveyor track 10 produced by an additive process according to a first embodiment of the present invention is shown in different views in Figures 2 to 5.

[0071] In contrast to the conventional solution, the conveyor track 10 is manufactured here in a single, continuous piece using an additive manufacturing process, such as selective laser melting, selective laser sintering, or 3D printing. This new manufacturing process allows for a significantly more delicate design of the conveyor track 10, resulting in lower mass and improved flow characteristics compared to the prior art, while maintaining similar stiffness, comparable vibration characteristics, and the same conveying properties. Welds, edges, sharp corners, and horizontal surfaces can be completely or largely eliminated.

[0072] Instead of the retaining plates, two connecting rails 18 are provided here, which wind in opposite directions along the conveyor line S around the guide arrangement 12 and around the central axis C, connecting the guide rails 14 in one piece.

[0073] In the example shown, the two connecting rails 18 in a central area Sc and a distal end area Sd of the conveyor section S (see Fig. 3) each have the shape of a helix and wind themselves in opposite directions a total of a little more than twice completely around the guide arrangement 12 and the central axis C.

[0074] In a proximal end region Sp of the conveyor section S, the connecting rails 18 in the illustrated example deviate from the helical shape for reasons explained later and run parallel to each other in an arc in a vertical plane. The connecting rails 18 thus form a largely helical cage, which provides stability and rigidity to the conveyor track 10 and also ensures that, with the exception of the support structure 24 explained later, no additional support structures are required during the manufacturing process for the guide and connecting rails 14, 18. The arrangement of guide and connecting rails 14, 18 is largely or completely self-supporting during manufacturing.

[0075] This can be achieved, for example, by ensuring that the connecting rails 18 and guide rails 14 run at each point of the conveyor track at an angle to the conveyor track central axis C, which lies in a range between 0° and 45°, including the aforementioned interval limits.

[0076] A rounded cross-sectional shape of the connecting rails 18 allows for improved flow characteristics around the conveyor track 10 when supplied with sterile air from above, the direction of which is indicated by an arrow L in Fig. 2, thus reducing the deposition of particles during operation of the conveyor track 10.

[0077] The guide rails 14 run parallel to the central axis C in the proximal end region Sp and in the distal end region Sd (see Fig. 3), in the middle region they wind by half a turn, i.e. corresponding to a conveying angle of 180° around the conveying track central axis C, so that an object 16, when transported over the middle region Sc of the conveying track S, also performs a 180° turn around the central axis C, as illustrated by objects 16 which are shown at various points on the conveying track 10 in the guide arrangement 12.

[0078] In the proximal end region Sp and in the distal end region Sd of the conveying path S, the objects are moved only by vibration along the conveying direction T, without changing their rotational position with respect to the central axis C.

[0079] As can be seen in particular from the cross-sectional views of Fig. 5 and Fig. 7, the guide rails 14 have a teardrop shape in cross-section, which is rounded except for a single tip 14s (see Fig. 7) in order to reduce friction during the transport of the object 16 and to improve the flow characteristics of the guide arrangement 12.

[0080] Each of the tips 1 s preferably forms an angle α of less than 90°, in particular of about 80°, as shown in Fig. 7.

[0081] Furthermore, the three tips 14s together form, for example, an isosceles triangle in all cross-sectional views (see Fig. 7), wherein the tip 14s opposite the base of this triangle points to the conveyor track central axis C, while the other two tips 14s can each point in a direction which encloses an angle β of less than 45°, preferably less than 30°, with a connecting line V between the respective tip 14s and the guide track central axis C.

[0082] As illustrated by the cross-sectional views in partial figures (a) to (c) of Fig. 5, the configuration of exactly three guide rails 14 is particularly suitable for holding and guiding cylindrically symmetrical objects 16 that taper stepwise or continuously along their axis of symmetry Z (see Fig. 5(b) and (c)) in such a way that they can only move along the conveyor track S and rotate about the conveyor track's central axis C during this movement. This arrangement is therefore particularly suitable for plug transport.

[0083] In the proximal end region Sp of the conveyor section S, the guide rail 14, located furthest down in this region in Fig. 2, is widened in sections and has a sensor recess 19 (see Figs. 3 and 4) in which a sensor (not shown here) can be arranged or through which a detection beam from a sensor can pass to monitor the conveying movement of the objects 16 along the conveyor track 10 during operation of the vibratory conveyor. The shape of the connecting rails 18 in the proximal end region Sp was chosen so that the connecting rails 18 do not impede the detection process. To mount the conveyor track 10 on a support structure through which the vibration of the vibratory conveyor can be introduced, two support structures 22 are provided in or near the opposite end regions Sd, Sp of the conveyor section S and are formed integrally with the guide and connecting rails 14, 18.The support strip from the prior art (13 in Fig. 1) is omitted.

[0084] Each of the support structures 22 can have, for example, a cylindrical trunk section 22s and several branch sections 22a extending upwards from the trunk section 22a in different directions and branching out, wherein each branch section 22a can be connected at its distal end to at least one connecting rail 18 or at least one guide rail 14.

[0085] Overall, the support structures 22, as well as the rest of the conveyor track 10, have a rounded structure, particularly with an organic or bionic appearance, avoiding sharp edges and corners as well as horizontal surfaces.

[0086] As can best be seen in Figure 4, the support structure 22 in the illustrated example has two branch sections 22a in or near the proximal end region Sp, one of which extends upwards and in the transport direction T and is connected to the two connecting rails 18 at an intersection point 18k1. The other branch section 22a extends upwards from the trunk section 22s and against the transport direction T and is connected to the guide rail 14 shortly behind the sensor recess 19, which supports the object 16 from below in the proximal end region Sp.

[0087] The support structure 22 in or near the distal end region Sd has three branch sections 22a, one of which extends upwards from the trunk section 22s and opposite to the transport direction T, and is connected to the two connecting rails 18 at a further intersection point 18k2. The other two branch sections 22a extend upwards from the trunk section 22s symmetrically to each other at an angle to the transport direction and are each connected to a connecting rail 18 at a connection point 18v.

[0088] Threaded holes 23 can be provided on the underside of the trunk sections 22s, with which the conveyor track 10 can be screwed onto a support structure not shown here.

[0089] The support structures 22 are also designed with rounded edges and avoiding horizontal surfaces.

[0090] At one end, here the proximal end 10p of the conveyor track 10, for example a ring-shaped support structure 24 can be provided, which connects the guide rails 14 in one piece, and which has a flat support surface 25 that runs perpendicular to the conveyor track central axis C (see Fig. 2).

[0091] In the present example, the transport direction T coincides with the assembly direction of the manufacturing process (see Fig. 12), so that the conveyor track 10 under assembly can rest on an assembly substrate with the first produced support structure 24 during the manufacturing process.

[0092] Alternatively, it is of course possible to manufacture the conveyor track using an additive manufacturing process in such a way that the build direction runs opposite to the transport direction. In this case, a corresponding support structure can be provided at the distal end of the conveyor track.

[0093] In the present embodiment, an additional stabilizing bracket 26 is provided in the distal end region Sd of the conveying section 10 for stabilization purposes. The two arms 26a of this bracket, at least when viewed from below (see Fig. 4), appear as an extension of the two front arm sections 22a of the distal support structure 22 and converge above the guide rail 14, which is located furthest up at the distal end 10d, in a similar manner to the connecting rails 18 near the plane CC in Fig. 3. To enable the parallel conveying of several objects 16, a vibratory conveyor 100, as shown by way of example and in detail in Fig.Figure 9 shows that several (here eight) conveyor tracks 10 according to the invention are arranged next to each other and parallel to each other on a support structure 110 and are attached to it, wherein the support structure 110 is designed, for example, in the form of a base plate and serves to introduce the vibration which provides for the movement of the objects along the conveyor tracks 10.

[0094] A comparison with a corresponding construction with conventional conveyor belts in Fig. 8 shows at first glance that the construction according to the invention is considerably more permeable to the application of sterile air from above than the known solution.

[0095] Flow simulations also show that, compared to the prior art, dead spaces and turbulence in the flow can be significantly reduced by the solution according to the invention.

[0096] Furthermore, in the conventional design shown in Fig. 8, different versions of the conveyor tracks 10 had to be manufactured and installed due to space constraints, depending on the position of the retaining plates 11. Thanks to the space-saving design of the new conveyor tracks 10 in Fig. 9, only a single variant of the conveyor track is now required.

[0097] From above, the effect of the new helical structure of the connecting rails is also visible. In Fig. 8, one sees an almost closed surface block formed by the retaining plates 11 of the conventional solution, which is problematic for the flow of sterile air. In Fig. 9, i.e., the new design, the permeability and openness are shown with the same frequency and stability.

[0098] Fig. 10 shows, in a perspective view, further parts of a vibratory conveyor 100 according to the invention, comprising a vibratory feed bowl 120 for storing the objects to be conveyed and a sorting device (distributor rake) 130 adjoining it. From the sorting device, eight objects at a time can be fed in the correct orientation to the eight adjacent conveyor tracks 10, i.e., with the end facing upwards, which is later to be placed in a container. On the conveyor tracks 10, the objects are then turned 180°. A vibratory drive (not shown here) can be arranged under the vibratory feed bowl 120 and the conveyor tracks 10, or under the support structure 110. The feed bowl 120, the distributor rake 130, and the conveyor tracks 10 are also referred to as the feeder.

[0099] At the distal end 10d of the conveyor tracks 10, a receiving device 140 is positioned, which receives the closure plugs on the conveyor tracks 10, each rotated by 180°, in order to insert them into containers not shown here, which are passed under the receiving device 140 in a timed sequence, as indicated by arrow B in Fig. 10.

[0100] Fig. 11 is an extremely simplified representation of a flowchart of an embodiment of a method according to the invention for producing a conveyor track in an additive manufacturing process.

[0101] In a first step S1, data is ordered or generated that defines the shape of the conveyor track, for example CAD data for the shape shown in Figures 2-5.

[0102] Then, in step S2, the conveyor belt is built up layer by layer in an additive process based on the provided data, for example in a DMG SLS printer, in which up to 28 conveyor belts can currently be produced simultaneously in 200h.

[0103] After assembly, various post-processing steps can follow. For example, the conveyor tracks are first removed from the base plate of an assembly chamber. Support structures, which may be present in the area of ​​the support structures to brace them during manufacturing, can be removed, for example, by milling, and a thread can be cut on the underside of the support structures. Cleaning and surface treatment of the conveyor track can involve processes such as glass bead blasting, sandblasting, vibratory finishing (tumbling), and / or electropolishing.

[0104] Fig. 12 illustrates, in a highly simplified manner, essential parts of a known system 500 for carrying out the additive manufacturing process, in the example shown being selective laser melting. The conveyor tracks, which are still under construction, are labeled 10' in Fig. 12.

[0105] The system 500 comprises in particular a build-up chamber 540 which can be moved in the z-direction by means of a lifting device 520 in accordance with the double arrow Z shown, a source 510 for laser radiation 515, the focus of which can be selectively adjusted in a plane E perpendicular to the z-direction, and a control device 550 for automatically controlling the various components of the system 500, in particular for controlling the lifting position of the build-up chamber and for controlling and adjusting the laser radiation 515.

[0106] The material to be processed 150, in particular stainless steel powder, is applied layer by layer to the floor 530 of a build-up chamber 540, smoothed out, and then selectively fused locally at the desired locations using laser radiation 515, so that a solid layer of material forms at these locations after solidification.

[0107] The build-up chamber 540 is then lowered according to the thickness of the powder layer, and the process is repeated so that one or more conveyor tracks 10' are produced simultaneously layer by layer in the build-up direction A, with the build-up direction A running parallel to the central axis C of the conveyor tracks. During build-up, the resulting conveyor tracks 10' are supported on the floor 530 of the build-up chamber 540 by the first ring- or frame-shaped support structure 24 produced. Additional support structures are only required at the support structures, which are not visible in this view. Figure 12 clearly shows that the guide and connecting rails are sufficiently steep for a self-supporting build-up, i.e., they run at an angle to the build-up direction A of no more than 45°.Overall, the present invention completely redesigns the known conveyor belt, which was previously welded together manually from metal strips and retaining plates, and optimizes it with regard to additive manufacturing and subsequent application for pharmaceutical filling systems, particularly with regard to reducing friction and mass, improving the flow characteristics when exposed to sterile air, and the vibration behavior during operation.

Claims

Claims 1. Conveyor track (10) for a vibratory conveyor (100), wherein the conveyor track (10) is designed to guide an object (16) to be conveyed along a transport direction (T) over a predetermined conveying distance (S) and to rotate the object (16) by a predetermined conveying angle, in particular by 180°, about a conveyor track central axis (C) which runs parallel to the transport direction (T), wherein the conveyor track (10) has a guide arrangement (12) with several guide rails (14) which wind around the conveyor track central axis (C) along the conveying distance (S) according to the conveying angle, characterized in that the conveyor track (10) is manufactured in one piece in an additive manufacturing process, for example by selective laser sintering or 3D printing, preferably from stainless steel.

2. Conveyor track (10) according to claim 1, wherein each of the guide rails (14) has a teardrop shape in cross-section, with a single tip (14s) designed to be in contact with the object (16) when the object (16) moves over the conveyor track (S).

3. Conveyor track (10) according to claim 2, wherein each of the tips (14s) of the guide rails (14) forms an angle (a) of about 70° to about 90°, preferably of about 75° to about 85°, particularly preferably of about 80°.

4. Conveyor track (10) according to one of the preceding claims, wherein the guide arrangement (12) has exactly three guide rails (14).

5. Conveyor track (10) according to one of claims 1 to 4, wherein the conveyor track (10) further comprises at least one connecting rail (18) which winds at least once completely around the conveyor track central axis (C) and around the guide arrangement (12) along the conveyor route (S) and connects the guide rails (14) in one piece.

6. Conveyor (10) according to one of claims 1 to 4, wherein the conveyor (10) further comprises two connecting rails (18) which wind in opposite directions at least once completely around the guide arrangement (12) and the conveyor central axis (C) along the conveyor section (S) and connect the guide rails (14) in one piece.

7. Conveyor (10) according to one of claims 5 or 6, wherein the connecting rail (18) or each of the connecting rails (18) has at least sectionally the shape of a helix.

8. Conveyor (10) according to one of claims 5 to 7, wherein each of the guide rails (14) and the connecting rail or each of the connecting rails (18) runs at each point of the conveyor route (S) at an angle to the conveyor central axis (C) which is not less than 0° and not greater than 45°.

9. Conveyor track (10) according to one of the preceding claims, further comprising two support structures (22) arranged in or near opposite end regions (Sp, Sd) of the conveyor track (S) and designed to fix the conveyor track (10) on a support structure (110).

10. Conveyor track (10) according to claim 9 in combination with claim 6, wherein each of the two support structures (22) is connected to the connecting rails (18) at a crossing point (18k1 , 18k2) of the two connecting rails (18).

11. Conveyor track according to one of the preceding claims, wherein a sensor recess (19) is provided in an end region (Sp) of the conveyor track (S) on one of the guide rails (14).

12. Conveyor (10) according to one of the preceding claims, wherein the conveyor (10) has at one end (10p) a preferably ring-shaped or frame-shaped support structure (24) which integrally connects the guide rails (14) and preferably also the connecting rails (18), and which has a flat support surface (25) perpendicular to the conveyor's central axis (C).

13. Conveyor (10) according to one of the preceding claims, wherein a lowest natural frequency of the conveyor (10) is at least 250Hz, preferably at least 400Hz, particularly preferably at least 500Hz.

14. Vibratory conveyor (100) particularly for plugs or other objects (16) with a cylindrically symmetrical basic shape, preferably for medical or pharmaceutical applications, comprising a support structure (110), particularly in the form of a base plate, and at least one conveyor track (10) arranged on and attached to the support structure (110) according to one of the preceding claims, preferably several conveyor tracks (10) arranged side by side and parallel to each other on and attached to the support structure (110) according to one of the preceding claims.

15. Method for producing a conveyor track (10) according to any one of claims 1 to 13, in particular for a vibratory conveyor (100) according to claim 14, comprising the following steps: Providing (S1) data that defines the shape of the conveyor path (10), building up (S2) the conveyor path (10) layer by layer along a build direction (A) in an additive manufacturing process based on the provided data, in particular by selective laser melting or selective laser sintering.

16. Method according to claim 15 for producing a conveyor track (10) according to claim 5 or 6, preferably in combination with a further of the Claims 1 to 13, wherein the conveyor (10) is manufactured such that an arrangement formed from the guide rails (14) and the connecting rail (18) or the connecting rails (18) largely or completely supports and carries itself during manufacture.

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