Transportation system
By using a multi-carrier system and a second guide rail with constant curvature, the high cost and time consumption problems of existing transportation systems when moving along circular paths are solved, achieving low-cost, synchronous movement and constant centrifugal force transportation effects.
Patent Information
- Application Number
- CN202510995710.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-07-23
- Filing Date
- 2025-07-18
- Publication Date
- 2026-01-23
AI Technical Summary
Existing transportation systems struggle to move products or items along guide rails with low cost and minimal effort, especially when circular paths are required, and redesigning segments is expensive and time-consuming.
A multi-carrier system is adopted, including multiple linear motors and a second guide rail with constant curvature. Combined with a transport unit and a load-bearing element, the linear motors are controlled by a control unit to move the transport unit along the first guide rail and move the load-bearing element in the lateral direction, so as to achieve synchronization with the second guide rail and avoid segment design adjustments.
It enables the movement of products or items along guide rails with low cost and minimal effort, maintaining constant centrifugal force, adapting to different segment designs, and synchronously moving transport units to maintain product stability.
Smart Images
Figure CN121376482A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The invention relates to a transport system, in particular a multi-carrier system, and to a method of operating a transport system. BACKGROUND
[0002] Such a transport system has a plurality of linear motors, also called segments, which are arranged in a row and which define a guide rail for moving a transport unit or transport element along the guide rail. The linear motors can individually move, stop, accelerate and decelerate the transport unit so that the transport unit can carry a product or article along the guide rail between defined stations in an assembly line. The guide rail usually consists of straight sections and curved sections.
[0003] In certain cases, it can be desirable to move the product or article along a circular path. This can be the case when the transport system is intended to replace a rotary table and to cooperate with machines in the assembly line that have previously cooperated with the rotary table and that are therefore arranged in a circle around the transport system. In addition, the circular path keeps the centrifugal force acting on the product or article constant. As a result, the product or article is less likely to fall from the transport unit.
[0004] However, it is sometimes not possible to define a circular guide rail because of the available segments, which are usually a mix of straight segments and curved segments. Usually, the segments can be redesigned to enable the creation of a circular guide rail. However, the redesign is expensive and time-consuming.
[0005] It is therefore an object of the invention to provide a transport system and a method of operating a transport system that allows a product or article to be carried along a guide rail at low cost and with little effort, which guide rail is independent of the design of the segments. SUMMARY
[0006] This object is met by a transport system having the features of claim 1 and by a method of operating a transport system having the features of claim 13. Advantageous embodiments are defined in the dependent claims and result from the description and the drawings.
[0007] According to an aspect, the invention relates to a transportation system, in particular a multi-carrier system. The transportation system comprises a plurality of linear motors and at least one transportation unit, the plurality of linear motors being arranged in a row and having a first guide rail, a curved second guide rail, wherein the curvature of the second guide rail is constant, the at least one transportation unit having a transportation element and a carrier element, the transportation element being movable along the first guide rail in a movement direction which can be clockwise or counterclockwise by means of the linear motors, the carrier element being configured to move together with the transportation element in the movement direction when the transportation element travels along the first guide rail, wherein the carrier element is movable relative to the transportation element in a transverse direction extending transversely to the movement direction, and wherein the carrier element is guided at the second guide rail. The transportation system further comprises a control unit configured to control the linear motors for moving the transportation unit along the first guide rail.
[0008] In this specification, a linear motor can also be referred to as a segment. Similarly, a transportation unit can also be referred to as a carrier.
[0009] The first guide rail and the second guide rail are at least partially different, which means not only that they are two physically different guide rails, but also that they are at least partially different in their course, i.e. at least partially have a different course. In other words, for example, if the first guide rail and the second guide rail are superimposed, the first guide rail and the second guide rail are not congruent, at least not over their entire course.
[0010] The movement direction and the transverse direction in particular refer to a common movement coordinate system of the transportation element. The transverse direction here refers to a direction transverse, i.e. orthogonal, to the movement direction. The transverse direction can in particular be the direction of action of the centrifugal force. The movement direction can also be designated as X direction, and the transverse direction can also be designated as Y direction. A third Z direction in the coordinate system moving together with the transportation element extends orthogonal to the X direction and the Y direction. The Z direction can in particular correspond to the vertical direction when the transportation element moves horizontally.
[0011] The ability of the carrier element to move relative to the transportation element in the transverse direction means that the movement of the carrier element relative to the transportation element has at least one movement component in the transverse direction. It is not necessary to move precisely and exclusively in the transverse direction. In particular, the carrier element can be slidably mounted to the transportation element in the transverse direction.
[0012] Each linear motor can in particular have six outer surfaces, namely an upper side, a lower side, an outer side, an inner side, and two side surfaces. In this respect, the side surfaces of adjacent linear motors are spaced apart from each other by a small expansion gap of about 0.1 mm to 0.2 mm or are in direct contact with each other. The guide rail for the transportation element can be formed at the outer side. The inner side is arranged in the region of an inner space of the transportation system.
[0013] The transport elements are in particular magnetically driven. To this end, the transport elements have one or more permanent magnets, which are force-loaded by means of a varying and / or drifting magnetic field generated by a linear motor. The driving force causes the transport elements to move in the movement direction along the first guide rail. The transport elements can in particular move independently of and separately from one another. By means of the carrier elements, items, such as workpieces, products or goods, can be transported with the respective transport units.
[0014] The second guide rail can in particular be arranged at the outside of the segments. The second guide rail can be arranged radially outward from the first guide rail. The second guide rail can be mechanically mounted to the segments or at least some of the segments. However, the second guide rail can also be attached to a separate device or a part of a building, such as a wall or a floor.
[0015] According to the application, the curvature of the second guide rail is constant. For example, when the carrier elements travel along the second guide rail at a constant speed, the centrifugal forces acting on the carrier elements and on the items or products carried by the carrier elements are constant.
[0016] Furthermore, by providing a second guide rail having a constant curvature, it is possible to avoid adapting the design of the segments. Thus, the provision of a second guide rail for guiding the carrier elements contributes to a very cost-effective solution which can be realized with relatively little outlay.
[0017] The second guide rail can be circular in a top view. In particular, the second guide rail can be a closed, complete circle in a top view.
[0018] In a preferred embodiment, the first guide rail has straight and / or curved track segments, while the second guide rail is curved. Thus, the distance between the first guide rail and the second guide rail in the transverse direction can vary along the track. In the case of a first guide rail having straight and curved track segments, the first guide rail can be assembled together by using segments that are generally available in a modular design. The second guide rail can in particular be designed to enclose the first guide rail.
[0019] The carrier elements can be rotatable relative to the transport elements about an axis, which is perpendicular to a movement plane defined by the movement direction and the transverse direction. This enables the carrier elements to not only be movable relative to the transport elements in the transverse direction, but also to be rotatable relative to the transport elements about the axis at least to a certain extent. The maximum angle of the relative rotation can be individually adjusted as required. The relative rotation facilitates, for example, a quick compensation of movement changes of the transport elements relative to the carrier elements at transitions from straight segments to curved segments of the first guide rail.
[0020] The transport system or multi-carrier system can be formed such that the linear motor forms a closed first rail along which the transport unit or the plurality of transport units can theoretically continuously move in the same direction. However, the linear motor can also form an open first rail with a starting point and an end point. The second rail can also be a closed rail or an open rail.
[0021] Preferably, the second rail comprises a track and the carrier element has a roller rolling along the track, wherein the carrier element has in particular at least one roller on opposite sides of the track. The track in particular forms the second rail. When the carrier element is moved by the transport element, its roller moves along the track such that the carrier element is guided to move along the second rail.
[0022] One of the carrier element and the transport element can comprise a long hole and the other of the carrier element and the transport element can comprise a pin extending into the long hole to allow a relative movement of the carrier element in the transverse direction with respect to the transport element. Thus, the long hole serves to absorb a distance difference between the first rail and the second rail. In particular, the pin can extend perpendicularly when the movement plane is a horizontal plane.
[0023] The transport system can comprise two transport units, which together are referred to as a pair of transport units. The pair of transport units can travel along the rail synchronously, wherein a predetermined gap is maintained between the two transport units. The predetermined gap can be individually set as desired. The predetermined gap can be defined between the carrier elements of the pair of transport units. Synchronous means that the pair of transport units travels at substantially the same speed at any time, such that the predetermined gap can be maintained between the two transport units. This allows that a product or an article can be transported picked up by the carrier elements of the two transport units.
[0024] Preferably, the first rail has straight rail segments and curved rail segments and the control unit is configured to control the linear motor to decelerate the transport unit at a transition from a straight rail segment to a curved rail segment and to accelerate the transport unit at a transition from a curved rail segment to a straight rail segment. Changing the direction of movement at a constant speed when the transport element of the transport unit transitions from a straight segment to a curved segment involves an acceleration of the carrier element at the second rail. To compensate for this, the transport unit is decelerated. On the other hand, the transition from a curved rail segment to a straight rail segment involves a deceleration of the carrier element at the second rail. Therefore, the transport unit is accelerated to compensate for this. The deceleration and the acceleration in particular help to ensure that the carrier elements of the pair of transport units move synchronously along the second rail.
[0025] According to another aspect, the invention relates to a method of operating a transportation system, in particular a multi-cargo system, the transportation system comprising a plurality of linear motors and a control unit, the linear motors being arranged in a row and having a first guide rail, a curved second guide rail (wherein the curvature of the second guide rail is constant), at least one transportation unit having a transportation element movable along the first guide rail in a movement direction by means of the linear motor, and a carrier element configured to move together with the transportation element in the movement direction as the transportation element travels along the first guide rail, wherein the carrier element is movable relative to the transportation element in a transverse direction extending transversely to the movement direction, and wherein the carrier element is guided at the second guide rail. The method comprises controlling the linear motors for moving the transportation unit along the first guide rail.
[0026] Preferably, the transportation system comprises at least two transportation units which together are a pair of transportation units, wherein the method comprises controlling the linear motors so as to move the pair of transportation units for travelling synchronously along the guide rail, wherein a predetermined gap is maintained between the two transportation units, in particular between the carrier elements of the pair of transportation units.
[0027] Further, the first guide rail can have straight and curved track segments, wherein the method comprises controlling the linear motors so as to decelerate the transportation unit at a transition from a straight track segment to a curved track segment and to accelerate the transportation unit at a transition from a curved track segment to a straight track segment.
[0028] It has to be noted that features, details and advantages mentioned above with respect to the transportation system also apply to the method of operating the transportation system and vice versa, even if this is not mentioned separately in the description. BRIEF DESCRIPTION OF DRAWINGS
[0029] In the following, the invention will be described with reference to the exemplary embodiments schematically depicted in the drawings. In the drawings,
[0030] Figure 1 is a top view showing an embodiment of a multi-cargo system,
[0031] Figure 2 is Figure 1 shows Figure 1 another top view of the multi-cargo system of
[0032] Figure 3 shows Figure 2 a magnified view of detail A in DETAILED DESCRIPTION
[0033] In Figure 1 and Figure 2In a top view, a transport system 10 is shown, which is embodied as a multi-carrier system. The transport system 10 has a plurality of straight and curved linear motors 11, which are arranged in a row in order to define a closed first guide rail 12. As Figure 1 and Figure 2 shown, the first guide rail 12 has a generally polygonal shape with rounded corners in a top view. However, the first guide rail 12 can alternatively be an open guide rail with an end and a beginning and can have any other shape defined by the kind and order of the linear motors 11.
[0034] Furthermore, the transport system comprises a second guide rail 13, which has a constant curvature along its entire extension. In this embodiment, the second guide rail 13 is also a closed track. Thus, the second guide rail 13 is embodied as a complete circle. The second guide rail 13 comprises a track, which is not shown in detail. The second guide rail 13 can be mounted to at least some of the linear motors 11. Otherwise, the second guide rail 13 can also alternatively be mounted to a part of a different device or building, for example a floor or a wall.
[0035] A number of transport units 14 are provided, which can travel along the tracks 12, 13. The transport units 14 comprise a transport element 16 and a carrier element 17, respectively. The transport elements 16 can be driven along the first guide rail 12 by means of the linear motors 11, i.e. they are guided by the track defining the first guide rail 12 and magnetically driven by the linear motors 11, for example. The transport elements 16 have one or more permanent magnets (not shown), respectively, which are force-loaded by means of a varying and / or drifting magnetic field generated by the linear motors 11. The driving force causes the transport elements 16 to move in a movement direction X along the first guide rail 12. The transport elements 16 can be moved independently and separately from each other. In Figure 1 the movement direction X is shown as a clockwise direction, but can alternatively also be a counterclockwise direction.
[0036] As the transport elements 16 travel along the movement direction X, the respective carrier elements 17 move along with the transport elements 16 due to the mechanical connection. In the present embodiment, as Figure 3 shown, the transport elements 16 have a pin 20, which extends into an elongated hole 19 formed at the carrier element 17. By means of the pin 20 and the elongated hole 19, the transport elements 16 carry the respective carrier elements 17 when traveling along the first guide rail. At the same time, the elongated hole 19 ensures that the carrier elements 17 are movable relative to the transport elements 16 in a transverse direction Y transverse to the movement direction X. Thus, variations in the distance d between the guide rails 12, 13 due to the different shape of the guide rails 12, 13 can be compensated for. Furthermore, the carrier elements 17 are rotatable relative to the transport elements 16 about an axis, which is perpendicular to a movement plane of the transport units 14 defined by the movement direction X and the transverse direction Y. The axis is also the axis of symmetry of the pin 20.
[0037] The carrying element 17 comprises rollers 18 which roll along the track of the second guide rail 13. The rollers 18 are arranged on opposite sides of the track. In the present embodiment, each carrying element 17 comprises four rollers 18, two on each side of the track. By means of the carrying element 17, transport items such as workpieces, products or articles can be transported with the respective transport unit 14.
[0038] The transport system 10 further comprises a control unit (not shown) which controls the linear motor 11 for moving the transport unit 14 along the first guide rail 12. When the transport element 16 travels along the first guide rail 12, the respective carrying element 17 moves along with the transport element 16. Due to the rollers 18, the carrying element 17 follows the second guide rail 13. The trajectory of the carrying element 17 on which the transport items can be placed is thus a circle with constant curvature. This is particularly advantageous when the transport system 10 is intended to replace a rotary table and to cooperate with machines which have previously cooperated with the rotary table in the assembly line and which are thus arranged in a circle around the transport system 10. Furthermore, the circular trajectory keeps the centrifugal force acting on the products or articles constant.
[0039] It can be seen that in the present embodiment, the transport units 14 move as pairs of transport units 15, wherein each pair of transport units 15 consists of two transport units 14 in the present embodiment. The transport units 14 of each pair of transport units 15 travel synchronously together, which means that a predetermined gap g is maintained between the respective carrying elements 17 of the transport units 14 of each pair of transport units 15, i.e. one predetermined gap g is assigned to each pair of transport units 15. In addition to pairs of transport units 15 travelling as disclosed here, the transport units 14 can also travel in groups of more than two transport units 14.
[0040] It can be seen from Figure 1 that the gap g can be different for a pair of transport units 15. This means that each pair of transport units has an individual gap g. The gap g can for example be predetermined to be in the range of 50 mm to 350 mm, preferably in the range of 100 mm to 200 mm.
[0041] Since the transport units 14 of each pair of transport units 15 travel synchronously, this means that the respective carrier elements 17 can together carry an article or product. However, when the transport elements 16 of the transport units 14 reach the transition between a straight section and a curved section, this means that the change in the direction of movement X at a constant speed involves an acceleration of the associated carrier elements 17 at the second guide rail 13. In order to compensate for this acceleration, the transport units 14 decelerate at the transition. Likewise, the transition from a curved track section to a straight track section involves a deceleration of the carrier elements 17 at the second guide rail 13, so that the transport units 14 accelerate at the transition to compensate for this. The deceleration and acceleration, respectively, ensure that the carrier elements 17 of a pair of transport units 15 move synchronously along the second guide rail 13.
[0042] With the present application, it is possible to realize a guidance of the carrier elements 17 which follows a path with a constant curvature. At the same time, this can be realized independently of the design of the sections and, in particular, at low cost and with little effort. Thus, linear motors which are available can easily be used to provide a product which is well adapted to the customer's needs.
[0043] List of reference signs
[0044] 10 transport system
[0045] 11 linear motor
[0046] 12 guide rail
[0047] 13 guide rail
[0048] 14 transport unit
[0049] 15 pair of transport units
[0050] 16 transport element
[0051] 17 carrier element
[0052] 18 roller
[0053] 19 long hole
[0054] 20 pin
[0055] d distance
[0056] g predetermined gap
[0057] X direction of movement
[0058] Y transverse direction
Claims
1. A transport system, comprising: a plurality of linear motors arranged in a row and having a first guide rail, a curved second guide rail, wherein the curvature of the second guide rail is constant, at least one transport unit having a transport element and a carrier element, the transport element being movable along the first guide rail in a movement direction by means of the linear motors, the carrier element being configured to move together with the transport element in the movement direction as the transport element travels along the first guide rail, wherein the carrier element is movable relative to the transport element in a transverse direction extending transversely to the movement direction, and wherein the carrier element is guided at the second guide rail, and a control unit configured to control the linear motors for moving the transport unit along the first guide rail.
2. The transport system according to claim 1, wherein the transport system is a multi-car system.
3. The transport system according to claim 1, wherein the second guide rail is circular in a top view.
4. The transport system according to claim 3, wherein the second guide rail is a closed circle in a top view.
5. The transport system according to claim 1, wherein the first guide rail has straight and / or curved track segments.
6. The transport system according to claim 1, wherein a distance between the first guide rail and the second guide rail in the transverse direction is variable along the guide rails.
7. The transport system according to claim 1, wherein the carrier element is rotatable relative to the transport element about an axis perpendicular to a movement plane defined by the movement direction and the transverse direction.
8. The transport system according to claim 1, wherein at least one of the first guide rail and the second guide rail is a closed track.
9. The transport system according to claim 1, wherein the second guide rail comprises a railway and the carrier element has a roller rolling along the railway.
10. The transport system according to claim 9, wherein the carrier element has at least one roller on opposite sides of the railway.
11. The transport system according to claim 1, wherein one of the carrier element and the transport element comprises a long hole and the other of the carrier element and the transport element comprises a pin extending into the long hole to allow relative movement of the carrier element relative to the transport element in the transverse direction.
12. The transport system according to claim 1, further comprising two transport units, the two transport units together being a pair of transport units, wherein the pair of transport units travel along the guide rails synchronously, a predetermined gap being maintained between the two transport units.
13. The transport system according to claim 12, wherein the predetermined gap is defined between the carrier elements of the pair of transport units.
14. The transport system according to claim 12, wherein the first guide rail has straight track sections and curved track sections, wherein the control unit is configured to control the linear motors to decelerate the transport unit at a transition from a straight track section to a curved track section and to accelerate the transport unit at a transition from a curved track section to a straight track section.
15. A method of operating a transport system, the transport system comprising a plurality of linear motors arranged in a row and having a first guide rail, a curved second guide rail, wherein a curvature of the second guide rail is constant, at least one transport unit having a transport element and a carrier element, the transport element being movable along the first guide rail in a movement direction by means of the linear motors, the carrier element being configured to move together with the transport element in the movement direction as the transport element travels along the first guide rail, wherein the carrier element is movable relative to the transport element in a transverse direction extending transversely to the movement direction, and wherein the carrier element is guided at the second guide rail, and a control unit, wherein the method comprises: controlling the linear motors for moving the transport unit along the first guide rail.
16. The method according to claim 15, wherein the transport system is a multi-vehicle system.
17. The method according to claim 15, wherein the transport system comprises at least two transport units, the two transport units together being a pair of transport units, wherein the method comprises: controlling the linear motors so as to move a pair of transport units synchronously to travel along a guide rail, a predetermined gap being maintained between the two transport units.
18. The method according to claim 15, wherein the transport system comprises at least two transport units, the two transport units together being a pair of transport units, wherein the method comprises: controlling the linear motors so as to move a pair of transport units synchronously to travel along a guide rail, a predetermined gap being maintained between the carrier elements of a pair of transport units.
19. The method according to claim 15, wherein the first guide rail has straight track sections and curved track sections, wherein the method comprises: controlling the linear motors to decelerate the transport unit at a transition from a straight track section to a curved track section and to accelerate the transport unit at a transition from a curved track section to a straight track section.