Omnidirectional wheel and conveying installation
Patent Information
- Application Number
- EP2023761064
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-08-31
- Filing Date
- 2023-08-16
- Publication Date
- 2025-07-09
AI Technical Summary
Existing omnidirectional wheels in conveyor systems are inefficient due to space requirements and power loss between the driving mechanism and rollers, and they often have limited contact area with the goods being conveyed.
An omnidirectional wheel design featuring a worm drive with a combination of spherical rollers having an external helical thread, where the first and second sets of rollers are arranged at an angular offset and directly mesh with the drive screw, enhancing torque transfer and contact area, and utilizing a cage or frame mounting system for compactness and ease of assembly.
The design results in a compact, high-efficiency omnidirectional wheel with increased contact area for conveying goods, minimizing power loss and allowing for smooth operation with reduced installation space, while maintaining robustness and ease of maintenance.
Smart Images
Figure 1.1
Abstract
Description
[0001] Omnidirectional wheel and conveyor system
[0002] The invention relates to an omnidirectional wheel and a conveyor system with such an omnidirectional wheel.
[0003] Omnidirectional wheels are used to generate a preset speed without the need to pivot the omnidirectional wheel. Omnidirectional wheels are used, for example, in conveyor systems to convey and / or rotate piece goods, especially packages, in a specified direction.
[0004] DE 20 2016 006 843 U1 discloses an omnidirectional wheel in which spherical rollers have an external thread near their maximum diameter, each of which is driven by an associated drive gear. The drive gear, in turn, is driven by a worm shaft.
[0005] US 8752696 B2 describes an omnidirectional wheel drive in which the crowned rollers have a helical thread in the area of their maximum diameter, which is driven by a helical gear.
[0006] The invention is based on the object of providing an improved omnidirectional wheel.
[0007] The invention solves the problem by an omnidirectional wheel having the features of claim 1. It is advantageous, but not necessary, if the first set of rollers and / or the second set of rollers each have the same distance from the central shaft.
[0008] The advantage of the invention is that such an omnidirectional wheel can generally be constructed particularly compactly. Because the rollers are driven directly by the drive worm, no additional space is required between the central shaft and the rollers.
[0009] Another advantage is that the omnidirectional wheel usually has a comparatively high efficiency. In other words, the loss between the drive power and the power that can be transmitted via the rollers is minimal. This is due to the favorable combination of worm drive and helical gearing.
[0010] Another advantage is the large contact area between the rollers and the material being conveyed. In particular, the area of the rollers where the external thread is located can also contact and move the material being conveyed.
[0011] It is particularly advantageous if the first-set rollers and the second-set rollers mesh directly with the drive worm. In other words, the torque is transmitted directly from the drive worm to the first-set rollers and the second-set rollers without an intermediate transmission unit.
[0012] In the context of the present description, the feature that the rollers at least partially protrude beyond the bearing drum is understood in particular to mean that the rollers can come into contact with an external object, for example a package.
[0013] The feature that the first-set roller rotation axis runs transversely to the central shaft rotation axis is understood in particular to mean that an angular offset between the first-set roller rotation axis and the central shaft rotation axis is at least 42°, in particular at least 45° and at most 90°.
[0014] According to a preferred embodiment, the angular offset is 85° to 90°. According to a further preferred embodiment, the angular offset is 45° ± 3°. The first-set rollers and the second-set rollers are preferably arranged at equidistant angles. If there are exactly three first-set rollers—as provided in a preferred embodiment—they are each offset from one another by an offset angle of 120°. If there are exactly four first-set rollers—as provided in a preferred embodiment—they are offset from one another by an offset angle of 90°.
[0015] Preferably, the first-set rollers are arranged at the same axial first-set height relative to the central shaft. In other words, the projections of the centers of mass of the first-set rollers onto the central shaft's rotational axis are on top of each other, or at least so close together that they can be considered to be on top of each other to a good approximation. Alternatively, the first-set rollers can also be arranged at different axial heights. Preferably, the second-set rollers are arranged at the same axial second-set height relative to the central shaft, with the first-set height differing from the second-set height.
[0016] It is advantageous if the second set of rollers are arranged at an angular offset relative to the first set of rollers that corresponds to half the offset angle.
[0017] According to a preferred embodiment, the external thread has a helix angle of at least 3°, in particular at least 6°. Alternatively or additionally, the helix angle is at most 65°. In particular, the drive worm has a high-pitch thread.
[0018] Preferably, the first-set rollers and the second-set rollers have a barrel-shaped outer contour, at least in the area of the respective external thread. The external thread is preferably formed by recesses countersunk into the outer contour. This means, in particular, that without the recesses, the outer contour would be strictly convex in the circumferential and longitudinal directions.
[0019] It is advantageous if the tooth root of the external thread is concavely curved. This creates a particularly short area in which the external thread is formed, while simultaneously enabling good torque transfer from the drive worm to the external thread. It is particularly advantageous if the tooth root is more curved than an outer contour of the first-set roller in the area of the external thread with respect to the direction of the corresponding roller rotation axis.
[0020] The tooth base preferably has a tooth base curvature radius, and the drive worm has a drive worm outer radius. The quotient of the tooth base curvature radius as the numerator and the drive worm outer radius as the denominator is preferably between 2 and 0.5. This allows for a small installation space while still allowing a sufficiently high torque to be transmitted from the drive worm to the rollers.
[0021] According to a preferred embodiment, at least one roller, in particular a plurality of rollers, preferably all rollers, has (a) a first material region, called the toothing region, in which the external thread is formed, and (b) a second material region, called the conveying region, which differs from the first material region in terms of its hardness, its static friction coefficient compared to cardboard and / or plastic (for example acrylonitrile-butadiene-styrene copolymer). In other words, the rollers in the conveying region are tribologically optimized so that the rollers have good grip on cardboard and / or plastic containers. The material in the toothing region is preferably harder than the material in the roller shaft region.
[0022] The conveying area is preferably the area in which the rollers come into contact with the material being conveyed, i.e. the objects to be conveyed, during operation of the omnidirectional wheel, in particular of the conveyor system.
[0023] Preferably, at least one roller, in particular a plurality of rollers, preferably all rollers, are manufactured additively. According to a preferred embodiment, at least one roller, in particular a plurality of rollers, preferably all rollers, are coated and / or manufactured by injection molding. For example, the omnidirectional wheel in the conveying area can be constructed from rubber or silicone or comprise a rubber or silicone object. The bearing drum preferably has a cylindrical outer contour that has a bearing drum curvature in the circumferential direction. In the longitudinal direction, i.e. with respect to a section in the longitudinal axis direction, the rollers have a wheel curvature that preferably corresponds to the bearing drum curvature, i.e. deviates from it by in particular at most 20%.
[0024] It is advantageous if the outer contour of one of the rollers is designed so that the outer contours of the wheels of the first set of rollers extend along a common circle. When the omnidirectional wheel rotates around its central shaft axis, this results in particularly smooth running.
[0025] Preferably, a majority of the replacement rollers are of identical construction, in particular, all of the first-set rollers are of identical construction. Preferably, a majority of the second-set rollers, in particular, all of the second-set rollers, are of identical construction to each other and to the first-set rollers. In particular, all of the rollers are of identical construction.
[0026] Preferably, at least a majority of the rollers, in particular all of the rollers, are mounted on the bearing drum by means of a cage. A cage is understood to be a device by means of which the rollers are mounted and which can be separated from the bearing drum. The cage itself is attached to the bearing drum. This allows for easy installation of the rollers on the bearing drum from the axial outside (relative to the bearing drum). Furthermore, the gap between the bearing drum and the roller is thus generally advantageously smaller than it would be if the rollers were attached to the bearing drum from the axial outside without a cage.
[0027] Preferably, the cage is connected to the bearing drum by a snap connection, particularly a reversible one. A snap connection is understood to be a connection in which a positive connection is created, and during the creation of which a part, in this case preferably the cage, undergoes elastic deformation before the positive connection is achieved. The cage preferably has a snap hook.
[0028] Preferably, the snap connection is reversible, i.e., detachable. This allows the cage to be repeatedly detached from the bearing drum, and one of these can be attached, without damaging the cage or the bearing drum. Preferably, the cage contains a bearing for the corresponding roller. In particular, the roller is fully supported on the cage. This means that the bearing seat for the roller is formed entirely on the cage.
[0029] The cage is preferably made of plastic. For example, the cage can be designed as an injection-molded part. It is advantageous if the cage is constructed of reinforced, particularly fiber-reinforced, plastic. Alternatively or additionally, the cage can have an insert made of metal, for example. This reinforces the cage. Alternatively, the cage can be a metal injection-molded part.
[0030] The cage preferably has a bearing bush for supporting the roller. For example, the roller is rotatably mounted by means of a shaft, in particular made of metal. This shaft is accommodated in the bearing bush. It is advantageous, but not necessary, for the roller to rotate around the shaft. In other words, the shaft is stationary or rotates more slowly than the roller. This minimizes wear on the bearing bush. Preferably, exactly one roller is mounted on each cage and / or each roller is mounted on exactly one cage.
[0031] According to one embodiment, at least a majority of the rollers are mounted on the bearing drum by means of a frame. The frame, together with the bearing drum, forms a bearing seat for the roller. The frame is preferably connected to the bearing drum by a snap connection, in particular reversibly. A frame differs from a cage in that the cage completely supports the roller, i.e., the bearing seat is formed entirely on the cage. In contrast, the bearing seat is only partially formed on the frame; the rest of the bearing seat is formed on the bearing drum. The frame preferably has the additional features mentioned above for the cage.
[0032] It is advantageous if a slot between the roller on the one hand and the cage or the frame on the other hand is at most 1 mm. If the slot does not have a constant width, the average value of the slot width is at most 1 mm. In this way, the probability of an object to be conveyed being drawn into the slot is reduced. It is advantageous if, for at least a majority of the rollers, a tooth base of the rollers runs along a strip that runs spirally on the outer surface of a cylinder. In particular, a majority of the tooth bases, in particular all tooth bases, each run along a strip that runs spirally on the outer surface of a cylinder. In particular, the tooth bases are wired. In particular, the strip, in particular each strip, runs helically. Such a roller is particularly easy to manufacture.
[0033] Also according to the invention are an omnidirectional shaft and an omnidirectional matrix, each having all the components of an omnidirectional wheel according to the invention and additionally having at least a third set of rollers which (i) are mounted on the bearing drum so as to be rotatable about a respective axis of rotation which runs transversely to the central shaft axis of rotation, (ii) are arranged at an angular distance from one another around the central shaft and (iii) each have an external thread and mesh with the drive worm.
[0034] In the omnidirectional shaft, the sets of rollers are arranged along the central shaft's rotation axis. In the omnidirectional matrix, the omnidirectional wheels are arranged in a regular pattern. A regular pattern is one with translational symmetry.
[0035] With such an omnidirectional shaft, large objects resting on multiple rollers at the same time can be moved in a specified direction.
[0036] Preferably, the omnidirectional wheel or the omnidirectional shaft has (a) a bearing drum drive for rotating the bearing drum about the central shaft axis of rotation, (b) a central shaft drive for rotating the central shaft, and (c) a control unit configured to automatically control the bearing drum drive and the central shaft drive. The higher the rotational frequency of the bearing drum drive and the central shaft drive, the faster an object in contact with the rollers is conveyed. The greater the rotational frequency difference between the bearing drum drive and the central shaft drive, the more the object is conveyed in the axial direction relative to the central shaft axis of rotation. The control unit has or is connected to a digital memory in which the associated rotational frequency of the bearing drum drive and the central shaft drive is stored for each speed.This can be done, for example, as a formula or in the form of a characteristic map. Velocity is a vector and has a magnitude and a direction.
[0037] It is advantageous if (a) the bearing drum has a bearing rib for each initial set roller, (b) each bearing rib has two bearing points for each roller, (c) the bearing ribs are connected circumferentially by two connecting ribs each, and (d) the connecting ribs have a radial and / or concave recess in the circumferential direction between two bearing points. The connecting ribs are preferably of the same shape. This recess increases the stability of the bearing drum at the same weight.
[0038] It is particularly advantageous if both the first set of rollers and the second set of rollers are mounted on the bearing drum.
[0039] The invention is explained in more detail below with reference to the accompanying drawings.
[0040] Figure 1 in part 1a an omnidirectional wheel according to the invention in a perspective view, in part 1b the omnidirectional wheel according to figure 1a without the bearing drum and in part 1c a view perpendicular to the central shaft rotation axis,
[0041] Figure 2 in part 2a a first set roller in a perspective view, in part 2b the first set roller in a view perpendicular to the roller rotation axis or axial to the central shaft and in part 2c the first set roller in a sectional view, in part 2d the first set rollers and the second set rollers in a plan view in the axial direction,
[0042] Figure 3 shows a bearing drum in a perspective view in part 3a and a cross-sectional view in part 3b. Figure 4 shows an omnidirectional wheel unit according to the invention in part 4a, which has a bearing drum drive and a central shaft drive, and in part 4b an omnidirectional shaft and
[0043] Figure 5 shows an omnidirectional matrix according to the invention comprising a plurality of omnidirectional wheel units.
[0044] Figure 6 in the sub-figures 6a-6g a bearing drum for a double-row omnidirectional wheel,
[0045] Figure 7 in the sub-figures 7a-7c a (first set or second set) roller of an omnidirectional wheel according to the invention,
[0046] Figure 8 in part 8a an omnidirectional wheel according to the invention and an omnidirectional shaft according to the invention, with rollers fastened by means of a cage and in part 8b a perspective view of the cage,
[0047] Figure 9 in part figure 9a an omnidirectional wheel according to the invention and an omnidirectional shaft according to the invention, with rollers fastened by means of a frame and in part figure 9b a perspective view of the frame and
[0048] Figure 10 in the sub-figures 10a-1 Od a (first set or second set) roller of an omnidirectional wheel according to the invention.
[0049] Figure 1 shows an omnidirectional wheel 10 according to the invention with a central shaft 12 extending along a central shaft rotation axis A12. The omnidirectional wheel 10 has three first-set rollers 14.i (i=1, 2, 3) which are rotatably mounted about a respective first-set roller rotation axis Ai4.i. Between the central shaft rotation axis and the respective first-set rotation axis, an angular offset is formed, which, as in the present case, can be 90°, but does not have to be. In particular, the angular offset can be less than 90° and is preferably in the interval e [43°, 90°]. Figure 2d shows that the first-set rollers 14.i are arranged at an offset angle y around the central shaft 12. In the present case, y = 120°.
[0050] Figure 1a shows that the omnidirectional wheel 10 also has three secondary rollers 16.i, each of which is rotatably mounted about a secondary roller rotation axis Ai6.i (in Figure 1a: Aw.i). The secondary rollers 16.i are arranged at an angular distance around the central shaft 12 by the same offset angle y.
[0051] The first-set rollers 14.i each have a first-set roller external thread 18.i (in Figure 1a: 18.1), and the second-set rollers 16.i each have a second-set roller external thread 20.i (in Figure 1a: 20.1). The central shaft 12 has a drive worm 22 that meshes with both the first-set roller external threads 18.i and the second-set roller external threads 20.i, thus driving them.
[0052] Figure 1 shows that the first set of rollers 14. i and the second set of rollers 16. i are fastened to a bearing drum 24. The bearing drum 24 has a bearing drum rotation axis A24, about which the bearing drum 24 can be rotatably mounted. To rotate the bearing drum 24, the bearing drum can have a threaded portion 26. By means of a second threaded portion 28, the central shaft 12 can be rotated relative to the bearing drum 24. In this way, a speed v can be set which is determined with respect to a reference plane E. The reference plane E runs parallel to the central shaft rotation axis A12 and at a distance from the central shaft rotation axis A12 such that one of the rollers 14. i, 16. i touches the reference plane E. In order for such a reference plane E to exist, the rollers 14. i, 16. i partially project beyond the bearing drum 24.
[0053] Figure 2a shows that the first set rollers 14. i and the second set rollers 16. i have a spherical outer contour K.
[0054] Figure 2b shows that the first-set roller external thread 18 is formed by recesses 30.j that are countersunk into the outer contour K. Preferably, the number J of recesses is between 5 and 50.
[0055] A helix angle a exists between the respective roller rotation axis A and the direction of the tooth base. This angle is, for example, a = 5°. Figure 2c shows the recesses 30.1, 30.8. A tooth base G is concavely curved and has a tooth base curvature radius RG. The tooth base curvature radius RG is the radius of the circle that optimally approximates the tooth base G.
[0056] Figure 2d shows that the outer contour K of the rollers 14.i, 16.i has an outer contour curvature radius RK. A ratio V = RG / RK is preferably between 0.1 and 0.5. The drive worm 22 has a drive worm outer radius RA. The quotient Q = RG / RA is between 2 and 0.5.
[0057] Figure 3 shows that the bearing drum 24 has a bearing drum curvature radius Ri_ in the circumferential direction, which corresponds to the radius of the circumferential circumference. The circumferential circumference is the circle with the minimum radius surrounding the bearing drum. The bearing drum curvature radius RL corresponds to the outer contour curvature radius RK, which means that both should be as similar as possible, but can differ from each other by, for example, a maximum of 20%, in particular a maximum of 10%.
[0058] Figure 3a shows that the bearing drum 24 has a bearing rib 32.i for each initial set roller 14.i. Each bearing rib 32.i has two bearing points 34a.i, 34b.i for each roller. Thus, the first initial set roller 14.1 is mounted at the bearing points 34a.1 and 34b.1.
[0059] Each bearing web 32.i is connected to the adjacent bearing web 32.(i+1)mod3 by two connecting webs 36a.i, 36b.i (mod denotes the modulo function, mod(3+1)=1). Thus, the bearing web 32.1 is connected to the bearing web 32.2 by means of the connecting webs 36a.1, 36b.1. The connecting webs 36a.i, 36b.i can each have a radial depression 38a.i, 38b.i in the circumferential direction U between two bearing webs. The connecting webs are preferably of the same shape. The depressions 38a.i, 38b.i increase the stability of the bearing drum 24 at the same weight.
[0060] Figure 4a shows an omnidirectional wheel unit 40 according to the invention, which, in addition to the features according to claim 1, has a bearing drum drive 44 for rotating the bearing drum 24 about the central shaft rotation axis A12 and a central shaft drive 42 for rotating the central shaft 12. The omnidirectional wheel unit 40 can also have a control unit 46 for controlling the bearing drum drive 42 and the central shaft drive 44.
[0061] Figure 4b shows an omnidirectional shaft 48 according to the invention, which has the central shaft 12 and sets 50.m of rollers. The first set 50.1 of rollers contains the first set of rollers 14.i, and the second set 50.2 of rollers contains the second set of rollers 16.i. The total number M of sets of rollers is preferably at least K = 4 and at most K = 500. All rollers are driven via the central shaft 12.
[0062] Figure 5 shows a conveyor system 52 according to the invention with a plurality of omnidirectional wheel units 40.n, which are arranged in a regular pattern, in the present case checkerboard-like, and form a matrix 54.
[0063] The conveyor system 52 comprises a feed conveyor 56, by means of which a package 58 to be sorted is conveyed to a top side of the matrix 54. Using a detection device 60, for example a camera or an RFID reader, the package 58 is identified and assigned by a computing unit 62 to one of several discharge conveyors 64. p (p = 1, ... P; here: P = 9).
[0064] The computing unit 62 captures images from the camera 60 and calculates the position and orientation of the package 58 from these images. From these images, the computing unit 62 determines the omnidirectional wheel units 40.i' located below the package 58 and controls them so that the package 58 is conveyed to the assigned discharge conveyor 64.p'. It is possible for the computing unit 62 to control the corresponding control units 46.i' so that the package 58 is conveyed to a predetermined position, for example, with its longitudinal axis in the conveying direction of the corresponding discharge conveyor 64.p'.
[0065] Figure 6 shows in the sub-figures 6a-6g a bearing drum 24 for a two-row omnidirectional wheel.
[0066] Figure 7 shows, in sub-figures 7a-7c, a first-set roller or second-set roller of an omnidirectional wheel 10 according to the invention, which has a first material region 66 and a second material region 68. In the present case, the roller consists in the first material region 66 of a first plastic, for example, polyoxymethylene, and in the second material region 68 of a second plastic, which has a higher coefficient of static friction with cardboard as a friction partner than the plastic in the first material region 66, for example, silicone, rubber and / or thermoplastic urethane.
[0067] Figure 8a shows a partially exploded view of an omnidirectional wheel 10 according to the invention in a design as an omnidirectional shaft 48, in which the rollers are each mounted by means of a cage 70. The cage 70 surrounds the roller, in Figure 8a the roller 14.3, in a frame-like manner. The roller is rotatably mounted by means of a shaft 72. The shaft 72 can be accommodated in bearing bushes 74.1, 74.2, but this is not necessary. The cage 70 forms a snap connection with the bearing drum 24. For this purpose, the cage 70 can have at least one snap hook 76. A bearing seat 78 of the shaft 72 is formed entirely on the cage 70.
[0068] The omnidirectional shaft 48 can have third-set rollers 80.i, which are constructed and arranged like the first-set rollers 14.i. An axial height H is shown. It can be seen that the first-set rollers 14.i are arranged at the same axial height, the first-set height Hu. The second-set rollers 16.i are arranged at the second-set height H, which differs from the first-set height Hu.
[0069] Using the cage 70, the rollers can be attached to the bearing drum 24 from the axial outside (as shown in Figure 8a). A gap S between the roller and the cage is so small that it is very unlikely that objects to be conveyed will be drawn into the gap.
[0070] Figure 8b shows the cage 70 in a perspective view.
[0071] Figure 9a shows a partially exploded view of an omnidirectional wheel 10 according to the invention in a configuration as an omnidirectional shaft 48, in which the rollers are mounted by means of a frame 82. A first bearing seat part 78a is formed on the frame 82. A second bearing seat part 78b, however, is formed on the bearing drum 20. The bearing drum 24 could also be referred to as a bearing tube or bearing shaft. The frame 82 is connected to the bearing drum 24 by means of a snap connection. For this purpose, the frame 82 can have a snap hook 76.
[0072] Figure 9 b shows the frame 82 in a perspective view.
[0073] The cage 70 (Figure 8b) and the frame 82 (Figure 9b) can each have actuating holes 84 designed for the insertion of a tool W, by means of which the snap hook 76 can be moved from its closed position to an open position. For this purpose, the tool W presses, for example, on the snap hook 76. In its closed position, the positive connection exists between the cage 70 or the frame 72 and the bearing drum 24.
[0074] Figure 10a shows a roller according to a preferred embodiment. The tooth base G runs along a flat strip that spirals along the outer surface of a cylinder.
[0075] Figure 10b shows a roller 14.1 constructed from three components, namely a central part 86 and two caps 88.1, 88.2. The caps 88.1, 88.2 are constructed from a material that has a lower hardness than the material of the central part 86. As a result, the caps 88.1, 88.2 generally experience greater wear, but the grip on the objects being conveyed is improved.
[0076] Figure 10c shows the central part 86, which is a plastic injection-molded part. Figure 10d shows the cap 88.1, which is also a plastic injection-molded part and is designed to be positively connected to the central part 86.
[0077] The central part 86 is made of POM (polyoxymethylene), for example. The caps 88.1, 88.2 are made of polyurethane, for example. The central part 86 can have several struts 90.j (e.g., j = 1, 2, ... 6) that interact in a form-fitting manner with recesses 92.j in the caps.
[0078] Figure 11 shows an alternative embodiment of a roller 14 for an omnidirectional wheel according to the invention, an omnidirectional shaft according to the invention, and an omnidirectional matrix according to the invention. The caps 88.1, 88.2 are injection-molded onto the central part 86. Preferably, the caps are integrally molded onto the central part 86. To manufacture the roller 14, the central part 86 is first manufactured by plastic injection molding.
[0079] The caps 88.1, 88.2 are then injection-molded onto the central part 86 in the same injection mold or - which is preferred but not necessary - in a different injection mold. The central part 86 is - which represents a preferred embodiment even without the other features of the described embodiment - axially permeable to liquids so that plastic can and does pass from one side along the axis of rotation of the roller 14 to the other side when the caps 88.1, 88.2 are injection-molded. In other words, the caps 88.1, 88.2 are connected to one another in one piece, i.e. without joints, directly (i.e. not via an intermediate element). It is advantageous if the caps 88.1, 88.2 are injection-molded from one side of the central part 86, for example from the side of the cap 88.1. The material that forms the other cap, in the example cap 88.2, flows through the central part 86.
[0080] When molding the caps 88.1, 88.2, the open tooth valleys are preferably sealed using slides. These slides can each create a circumferential groove 94.1, 94.2.
[0081] List of reference symbols 30 Deepening
[0082] 32 bearing bridge
[0083] 10 Omnidirectional wheel 34a, 34b bearing point
[0084] 12 Central shaft 36 Connecting bridge
[0085] 14 first set rollers 38a, 38b recess
[0086] 16 second set casters 40 omnidirectional wheel unit
[0087] 18 First set roller external thread 42 Central shaft drive
[0088] 20 Second set roller external thread 44 Bearing drum drive
[0089] 22 Drive worm 46 Control unit
[0090] 24 Bearing drum 48 Omnidirectional shaft
[0091] 26 first thread section 50 set
[0092] 28 second threaded section 52 conveyor system matrix 92 recess
[0093] Feeder package a helix angle
[0094] Detection device cp Angular offset Computing unit y Offset angle Discharge conveyor A Roller rotation axis first material area A12 Central shaft rotation axis second material area Ai4.i First set roller rotation axis cage E Reference plane shaft G Tooth base
[0095] Bearing bush K Outer contour Snap hook M Total number of sets of rollers Bearing seat RG Tooth base curvature radius Third set roller RK Outer contour curvature radius Frame RL Bearing drum curvature radius Mounting hole U Circumferential direction Central part v Speed Cap W Tool Strut
Claims
Patent claims 1. Omnidirectional wheel (10) with (a) a central shaft (12) extending along a central shaft rotation axis (A12) and (b) a bearing drum (24) rotatable about a bearing drum rotation axis, (c) at least three first set rolls (14.i) which (i) are mounted on the bearing drum (24) so as to be rotatable about a respective first-set roller rotation axis (Au.i) which runs transversely to the central shaft rotation axis (A12), (ii) are arranged at an angular distance from one another around the central shaft (12) and (iii) each have a helical first set roller external thread (18) (d) at least three second set rolls (16. i) which (i) are mounted on the bearing drum (24) so as to be rotatable about a respective second set roller rotation axis which runs transversely to the central shaft rotation axis (A12), (ii) are arranged at an angular distance from one another, in particular with a respective angular offset (q>) to the first set rollers (14. i), around the central shaft (12) and (iii) each have a helical second set roller external thread (20) (e) wherein the rollers project at least partially beyond the bearing drum (24) and (f) wherein the omnidirectional wheel (10) is designed such that a rotation of the central shaft (12) about the central shaft rotation axis (A12) relative to the bearing drum (24) causes a rotational movement of the rollers about their respective rotational axes in the same direction of rotation, characterized in that (g) the central shaft (12) has a drive worm (22) that meshes with the external threads. Omnidirectional wheel (10) according to claim 1, characterized in that the at least three first-set rollers (14.i) are arranged at the same distance from the central shaft, and the at least three second-set rollers (16.i) are arranged at the same distance from the central shaft. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that (a) the first set rollers (14.i) and the second set rollers (16.i) have a barrel-shaped outer contour (K) at least in the area of the respective external thread and (b) the external thread is formed by recesses (30. i) sunk into the outer contour (K) and (c) the external thread extends over at most half, in particular at most 0.4 times the height of the rollers. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that the tooth base (G) of the external thread is concavely curved and / or a helix angle α of the external thread is between 3° and 65°. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that the tooth base (G) is more strongly curved than an outer contour (K) of the first-set roller (14) in the region of the external thread with respect to the direction of the wheel's rotation axis. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that (a) the tooth root (G) has a tooth root curvature radius (Rc), (b) the drive worm (22) has a drive worm outer radius and (c) a quotient of the tooth base curvature radius (Rc) as numerator and the drive worm outer radius as denominator is between 2 and 0.
5. Omnidirectional wheel (10) according to one of the preceding claims, characterized by at least a third set (50) of rollers, which (i) are mounted on the bearing drum (24) so as to be rotatable about a respective axis of rotation which runs transversely to the central shaft axis of rotation (A12), (ii) are arranged at an angular distance from one another around the central shaft (12) and (iii) each have an external thread and mesh with the drive worm (22). Omnidirectional wheel (10) according to one of the preceding claims, characterized by (a) a bearing drum drive (44) for rotating the bearing drum (24) around the central shaft rotation axis (A12), (b) a central shaft drive (42) for rotating the central shaft (12) and (c) a control unit (46) which is designed to automatically control the bearing drum drive (44) and the central shaft drive (42).
9. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that (a) the bearing drum (24) has a bearing web (32) for each first-set roll (14), (b) each bearing web (32) has two bearing points (34a, 34b) for one roller each, (c) the bearing webs (32. i) are connected in the circumferential direction (U) with two connecting webs each and (d) and the connecting webs (36. i) have a radial depression (38a, 38b) in the circumferential direction (U) between two bearing points (34a, 34b).
10. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that at least one roller (a) has a first material region (66) in which the external thread (18, 20) is formed, and (b) a second material region (68) which differs from the first material region in terms of its hardness, its coefficient of static friction with respect to cardboard and / or acrylonitrile-butadiene-styrene copolymer.
11. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that (a) at least a majority of the rollers are mounted on the bearing drum by means of a cage, (b) the cage is reversibly connected to the bearing drum by a snap connection.
12. Omnidirectional wheel (10) according to claim 11, characterized in that the cage (a) is made of plastic and (b) has a bearing bush for supporting the roller.
13. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that the rollers are rotatably mounted by means of a shaft, wherein the roller is rotatable relative to the shaft.
14. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that (a) at least a majority of the rollers are mounted on the bearing drum by means of a frame, (b) the frame together with the bearing drum forms a bearing seat for the roller and that (c) the frame is reversibly connected to the bearing drum by a snap connection.
15. Omnidirectional wheel (10) according to one of claims 11 to 14, characterized in that a slot between the roller on the one hand and the cage or the frame on the other hand is at most 1 mm.
16. Omnidirectional wheel (10) according to one of the preceding claims, characterized in that for at least a majority of the rollers, a tooth base of the rollers runs along a strip which runs spirally on the outer surface of a cylinder.
17. Omnidirectional shaft (48) with (a) a central shaft (12) extending along a central shaft rotation axis (A12) and (b) a bearing drum (24) rotatable about a bearing drum rotation axis, (c) at least three first set rolls (14.i) which (iv) are mounted on the bearing drum (24) so as to be rotatable about a respective first-set roller rotation axis (Aui) which runs transversely to the central shaft rotation axis (A12), (v) are arranged at equal distances and angularly spaced from one another around the central shaft (12) and (vi) each have a helical first set roller external thread (18) (d) at least three second set rolls (16. i) which (iv) are mounted on the bearing drum (24) so as to be rotatable about a respective second set roller rotation axis which runs transversely to the central shaft rotation axis (A12), (v) are arranged at the same distance and angularly spaced from each other and with a respective angular offset (q>) to the first set rollers (14. i) around the central shaft (12) and (vi) each have a helical second set roller external thread (20) (e) wherein the rollers project at least partially beyond the bearing drum (24), (f) wherein the omnidirectional shaft (48) is designed such that a rotation of the central shaft (12) about the central shaft rotation axis (A12) relative to the bearing drum (24) causes a rotational movement of the rollers about their respective rotational axes in the same direction of rotation, (g) wherein the central shaft (12) has a drive worm (22) which meshes with the external threads and (h) at least a third set of rollers which - are mounted on the bearing drum so that they can rotate around a respective axis of rotation which runs transversely to the central shaft axis of rotation, - are arranged at an angular distance from each other around the central shaft and - each have an external thread and mesh with the drive worm. Conveyor system (52) with (a) a plurality of omnidirectional wheels (10) or omnidirectional shafts (48) according to one of the preceding claims, which are arranged along a conveying plane, and (b) a controller which is designed to automatically carry out a method comprising the steps (i) detecting a desired conveying speed for at least one omnidirectional wheel (10) or one omnidirectional shaft (48) and (ii) Controlling the bearing drum drive (44) and the central shaft drive (42) of this omnidirectional wheel (10) or this Omnidirectional shaft (48), such that a contact point speed of the points of the at least one omnidirectional wheel (10) or the omnidirectional shaft (48) which projects furthest beyond the conveying plane corresponds to the desired conveying speed.