Transport system
The transportation system achieves efficient, low-cost transport along a circular path by integrating a second guide track with constant curvature, overcoming the need for segment redesign, and maintaining consistent centrifugal force.
Patent Information
- Application Number
- JP2025122525
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-07-23
- Filing Date
- 2025-07-22
- Publication Date
- 2026-02-04
AI Technical Summary
Existing transportation systems face challenges in creating a circular guideway without redesigning segments, which is costly and time-consuming.
A transportation system with a first guide track and a second guide track of constant curvature, allowing transport units to move along a circular path without altering existing segments, using linear motors and a control unit to manage transitions between straight and curved segments.
Enables cost-effective and efficient transport along a circular path, maintaining constant centrifugal force, suitable for replacing rotary tables in assembly lines, with minimal redesign effort.
Smart Images
Figure 2026017538000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a transportation system, in particular a multi-carrier system, and to a method of operating a transportation system. [Background technology]
[0002] Such a transport system has multiple linear motors, also called segments, arranged in a line to define a guideway for moving transport units or elements along the guideway. The linear motors can individually move, stop, accelerate, and decelerate the transport units so that they can carry products or articles along the guideway between defined stations in an assembly line. The guideway is typically composed of straight and curved sections.
[0003] In certain circumstances, it may be desirable to move products or articles along a circular path. This may be the case when the transport system is intended to replace a rotary table and to cooperate with machines in an assembly line that previously cooperated with the rotary table and are therefore arranged in a circle around the transport system. Furthermore, a circular path keeps the centrifugal force acting on the products or articles constant. Therefore, the products or articles are less likely to fall off the transport unit.
[0004] However, it may not be possible to define a circular guideway with the available segments, which are usually a mixture of straight and curved segments. Generally, the segments can be redesigned to allow for the creation of a circular guideway. However, redesign is expensive and time consuming. Summary of the Invention [Problem to be solved by the invention]
[0005] It is therefore an object of the present invention to provide a transportation system and a method for operating a transportation system that allows products or objects to be transported along a guide track that is independent of the design of the segments, at low cost and with little effort. [Means for solving the problem]
[0006] This object is met by a transport system having the features of claim 1 and by a method for 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 one aspect, the present invention relates to a transportation system, specifically a multi-carrier system. The transportation system includes a plurality of linear motors arranged in a row and having a first guide track, a curved second guide track having a constant curvature, transport elements movable by the linear motors along the first guide track in a movement direction that may be clockwise or counterclockwise, and at least one transport unit having a carrying element configured to be moved together with the transport elements in the movement direction when the transport elements move along the first guide track, the carrying element being movable relative to the transport elements in a transverse direction extending transverse to the movement direction, and the carrying element being guided in the second guide track. The transportation system further includes a control unit configured to control the linear motors to move the transport units along the first guide track.
[0008] Within the scope of this specification, the linear motors may also be referred to as segments, and similarly, the transport units may also be referred to as carriers.
[0009] The first guide track and the second guide track are at least partially different, which not only means that they are two physically different guide tracks, but also that they are at least partially different in terms of their paths, i.e., have at least partially different paths. In other words, the first guide track and the second guide track do not coincide, at least not over their entire paths, for example when they are superimposed.
[0010] The moving direction and the transverse direction refer in particular to the co-moving coordinate system of the transport element. Here, the transverse direction means the direction transverse to the moving direction, i.e., the direction perpendicular to the moving direction. The transverse direction may specifically be the direction in which centrifugal force acts. The moving direction may also be referred to as the X direction, and the transverse direction may also be referred to as the Y direction. A third Z direction in the coordinate system moving with the transport element extends perpendicular to the X and Y directions. The Z direction may specifically correspond to the vertical direction when the transport element moves horizontally.
[0011] The conveying element being movable relative to the transport element in the transverse direction means that the movement of the conveying element relative to the transport element has at least one movement component in the transverse direction. It is not essential that the movement takes place exactly and exclusively in the transverse direction. In particular, the conveying element can be slidably attached to the transport element in the transverse direction.
[0012] Each linear motor may specifically have six outer surfaces: an upper surface, a lower surface, an outer surface, an inner surface, and two side surfaces. In this regard, the side surfaces of adjacent linear motors may be spaced apart by a small expansion gap of approximately 0.1 mm to 0.2 mm or may be in direct contact with each other. Guide tracks for the transport elements may be formed on the outer surface. The inner surface may be located within the interior space of the transport system.
[0013] The transport elements are specifically magnetically driven. For this purpose, they have one or more permanent magnets that are acted upon by a driving force generated by a linear motor, which generates a varying and / or wandering magnetic field. The driving force causes the transport elements to move in a direction along the first guide track. The transport elements can specifically be moved independently and separately from one another. The transport elements allow transported goods, such as workpieces, products, or articles, to be transported with the respective transport units.
[0014] The second guide track can be arranged, in particular, on the outside of the segment. The second guide track can also be arranged radially outward from the first guide track. The second guide track can be mechanically attached to the segments or to at least some of the segments. However, it is also possible for the second guide track to be attached to a separate device or to part of a structure such as a wall or base.
[0015] According to the invention, the curvature of the second guide track is constant, i.e., if the conveying element moves at a constant speed along the second guide track, the centrifugal force acting on the conveying element and on the article or product conveyed by the conveying element is constant.
[0016] Furthermore, by providing a constant curvature to the second guide track, the design of the segments can be left unadapted. Thus, providing a second guide track for guiding the conveying elements contributes to a very cost-effective solution that can be achieved with relatively little effort.
[0017] The second guide track may be circular in top view, specifically, the second guide track may be a closed complete circle in top view.
[0018] In a preferred embodiment, the first guide track has straight and / or curved track segments, while the second guide track is curved. Therefore, the transverse distance between the first and second guide tracks can vary along the track. With a first guide track having straight and curved track segments, the first guide track can be assembled together using segments that are typically available in a modular design. The second guide track can be specifically designed to surround the first guide track.
[0019] The conveying element may be rotatable relative to the transport element about an axis perpendicular to the plane of movement defined by the direction of movement and the transverse direction. This allows the conveying element to be not only movable relative to the transport element in the transverse direction but also rotatable relative to the transport element at least to some extent about the axis. The maximum angle of relative rotation can be individually adjusted as needed. The relative rotation serves to quickly compensate for changes in the movement of the transport element relative to the conveying element, for example, at the transition from the straight segment to the curved segment of the first guide track.
[0020] The transport system or multi-carrier system can be configured so that the linear motor forms a closed first guideway along which the transport units can theoretically move infinitely in the same direction. However, it is also possible for the linear motor to form an open first guideway with a starting point and an end point. The second guideway can also be a closed or open guideway.
[0021] Preferably, the second guide track comprises a rail, and the transport element has rollers that roll along the rail, and the transport element in particular has at least one roller on each side of the rail. The rail in particular forms the second guide track. When the transport element is moved by the transport element, the rollers of the transport element move along the rail so that the transport element is guided to move along the second track.
[0022] One of the conveying element and the transport element can have a slot, and the other of the conveying element and the transport element can have a pin extending into the slot to allow relative movement of the conveying element with respect to the transport element in the transverse direction. The slot thus serves to absorb the distance difference between the first guide track and the second guide track. In particular, the pin can extend vertically when the movement plane is horizontal.
[0023] The transport system may include two of the transport units, collectively referred to as a transport unit pair. The transport unit pair may move synchronously along a guideway with a predetermined gap maintained between the two transport units. The predetermined gap may be set individually as needed. The predetermined gap may be defined between the transport elements of the transport unit pair. Synchronously means that the transport unit pair moves at essentially the same speed at all times so that the predetermined gap can be maintained between the two transport units. This allows products or objects to be picked up and transported by the transport elements of the two transport units.
[0024] Preferably, the first guide track has straight and curved track segments, and the control unit is configured to control the linear motor to decelerate the transport unit at transitions from the straight track segments to the curved track segments and to accelerate the transport unit at transitions from the curved track segments to the straight track segments. When the transport elements of the transport unit transition from the straight segment to the curved segment, a change in the direction of movement at a constant speed causes the transport elements in the second guide track to accelerate. To compensate for this acceleration, the transport unit is decelerated. On the other hand, the transition from the curved track segment to the straight track segment causes the transport elements in the second guide track to decelerate. Therefore, the transport unit is accelerated to compensate for this. The deceleration and acceleration are particularly useful for ensuring that the pair of transport elements of the transport unit move synchronously along the second guide track.
[0025] According to another aspect, the present invention relates to a method for operating a transportation system, particularly a multi-carrier system, comprising: a plurality of linear motors arranged in a row and having a first guide track; a curved second guide track having a constant curvature; transport elements movable by the linear motors in a movement direction along the first guide track; and at least one transport unit having transport elements configured to be moved together with the transport elements in the movement direction as the transport elements move along the first guide track, the transport elements being movable relative to the transport elements in a transverse direction extending transverse to the movement direction, the transport elements being guided in the second guide track; and a control unit. The method comprises controlling the linear motors to move the transport units along the first guide track.
[0026] Preferably, the transport system comprises at least two of the transport units that together form a pair of transport units, in which case the method comprises controlling the linear motors to move the pair of transport units synchronously along the guide track while maintaining a predetermined gap between the two transport units, in particular between the conveying elements of the pair of transport units.
[0027] Further, the first guide track can have straight and curved track segments, in which case the method comprises controlling the linear motor to decelerate the transport unit at transitions from the straight track segments to the curved track segments, and to accelerate the transport unit at transitions from the curved track segments to the straight track segments.
[0028] It should be noted that the features, details and advantages described above in relation to the transportation system also apply to the method of operating the transportation system, even if the description does not specifically mention it, and vice versa.
[0029] The invention will be explained below with reference to exemplary embodiments that are illustrated diagrammatically in the drawings. [Brief explanation of the drawings]
[0030] [Figure 1] FIG. 1 illustrates an embodiment of a multi-carrier system in a top view. [Figure 2] FIG. 2 is another top view of the multi-carrier system of FIG. 1. [Figure 3] FIG. 3 is an enlarged view of detail A in FIG. 2. DETAILED DESCRIPTION OF THE INVENTION
[0031] 1 and 2, a transportation system 10 is shown in top view and is embodied as a multi-carrier system. The transportation system 10 has multiple linear and curved linear motors 11 arranged in a row to define a closed first guide track 12. As shown in FIGS. 1 and 2, the first guide track 12 has an overall polygonal shape in top view with rounded corners. However, the first guide track 12 may instead be an open guide track with an end and a beginning, or may have any other shape defined by the type and order of the linear motors 11.
[0032] The transportation system further includes a second guideway 13, which has a constant curvature along its entire length. In this embodiment, the second guideway 13 is also a closed track. Therefore, the second guideway 13 is embodied as a complete circle. The second guideway 13 includes rails, which are not shown in detail. The second guideway 13 can be attached to at least some of the linear motors. Alternatively, the second guideway 13 can be attached to a different device or to part of a structure, such as a floor or wall.
[0033] Several transport units 14 are provided, each of which can move along the tracks 12, 13. Each transport unit 14 includes a transport element 16 and a conveying element 17. The transport elements 16 can be moved along the first guide track 12 by a linear motor 11. That is, the transport elements 16 are guided, for example, by rails defining the first guide track 12 and magnetically driven by the linear motor 11. Each transport element 16 has one or more permanent magnets (not shown) that are acted upon by a driving force due to a changing and / or wandering magnetic field generated by the linear motor 11. The driving force causes the transport elements 16 to move in a moving direction X along the first guide track 12. The transport elements 16 can be moved independently and separately from one another. In FIG. 1, the moving direction X is shown as clockwise, but it may alternatively be counterclockwise.
[0034] As the transport elements 16 move in the movement direction X, each transport element 17 moves together with the transport elements 16 due to the mechanical connection. In this embodiment, as can be seen in FIG. 3 , the transport elements 16 have pins 20 extending into slots 19 formed in the transport elements 17. Through the pins 20 and the slots 19, the transport elements 16 take each transport element 17 along as they move along the first guide track. At the same time, the slots 19 ensure that the transport elements 17 are movable relative to the transport elements 16 in a transverse direction Y that intersects the movement direction X. This allows compensation for changes in the distance d between the guide tracks 12, 13 due to the different shapes of the guide tracks 12, 13. Furthermore, the transport elements 17 are rotatable relative to the transport elements 16 around an axis perpendicular to the movement plane of the transport unit 14, which is defined by the movement direction X and the transverse direction Y. The axis is also the axis of symmetry of the pins 20.
[0035] The transport elements 17 comprise rollers 18 that roll along the rails of the second guide track 13. The rollers 18 are provided on both sides of the rails. In this embodiment, each transport element 17 comprises four rollers 18, two on each side of the rails. The transport elements 17 allow transport items, such as workpieces, products or goods, to be transported together with the respective transport unit 14.
[0036] The transport system 10 also includes a control unit (not shown) that controls the linear motors 11 to move the transport units 14 along the first guide track 12. When the transport elements 16 move along the first guide track 12, the respective conveying elements 17 move together with the transport elements 16. Rollers 18 cause the conveying elements 17 to move along the second guide track 13. The trajectory of the conveying elements 17, along which the transported items can be placed, is therefore a circle with a constant curvature. This is particularly advantageous when the transport system 10 is intended to replace a rotary table and to cooperate with machines in an assembly line that previously cooperated with a rotary table and are therefore arranged in a circle around the transport system 10. Furthermore, the circular trajectory keeps the centrifugal force acting on the products or objects constant.
[0037] As can be seen in the figure, in this embodiment, the transport units 14 move in pairs 15 of transport units, each pair 15 consisting of two transport units 14 in this embodiment. The transport units 14 of each pair 15 move together synchronously, which means that a predetermined gap g is maintained between the respective conveying elements 17 of the transport units 14 of each pair 15, i.e., one predetermined gap g is assigned to each pair 15. Besides moving in pairs 15 as disclosed herein, the transport units 14 can also move in groups of more than two transport units 14.
[0038] 1, the gap g may vary between pairs 15, meaning that each pair has an individual gap g. The gap g may be predetermined, for example, to be in the range of 50 mm to 350 mm, preferably 100 mm to 200 mm.
[0039] Since the transport units 14 of each pair 15 move synchronously, this means that the respective transport elements 17 can carry goods or products together. However, when the transport elements 16 of a transport unit 14 reach the transition between the straight and curved segments, this means that a change in the direction of movement X at a constant speed causes the associated transport elements 17 in the second guide track 13 to accelerate. To compensate for this acceleration, the transport units 14 are decelerated at the transition. Similarly, the transition from the curved track segment to the straight track segment causes the transport elements 17 in the second guide track 13 to decelerate, so the transport units 14 are accelerated at the transition to compensate for this. The deceleration and acceleration, respectively, ensure that the transport elements 17 of a transport unit pair 15 move synchronously along the second guide track 13.
[0040] According to the invention, guidance of the conveying elements 17 moving along a path with a constant curvature can be achieved. At the same time, this can be achieved independently of the segment design and with particularly low cost and effort. Therefore, available linear motors can be easily used to provide a product that is well adapted to customer needs. [Explanation of symbols]
[0041] 10 Transportation Systems 11 Linear motor 12 Guideway 13 Guideway 14 Transport Units 15 Transport Units 16 Transportation Elements 17 Conveying Elements 18 Laura 19 slotted hole 20-pin d distance g specified gap X direction of movement Y transverse direction
Claims
1. a plurality of linear motors arranged in a row and having a first guide track; a curved second guide track, the second guide track having a constant curvature; At least one transport unit having a transport element movable along the first guide track in a moving direction by the linear motor, and a transport element configured to be moved in the moving direction together with the transport element when the transport element moves along the first guide track, wherein the transport element is movable relative to the transport element in a transverse direction extending transversely to the moving direction, and the transport element is guided in the second guide track; a control unit configured to control the linear motor to move the transport unit along the first guide track; and A transportation system comprising:
2. the transportation system is a multi-carrier system; The transportation system of claim 1 .
3. The second guide track is circular in top view. The transportation system of claim 1 .
4. The second guide track is a closed circle in a top view. The transportation system of claim 3 .
5. the first guide track has straight and / or curved track segments; The transportation system of claim 1 .
6. a distance in the transverse direction between the first guide track and the second guide track is variable along the guide track; The transportation system of claim 1 .
7. the conveying element is rotatable relative to the transport element about an axis perpendicular to a plane of movement defined by the direction of movement and the transverse direction; The transportation system of claim 1 .
8. At least one of the first and second guide tracks is a closed track. The transportation system of claim 1 .
9. the second guide track comprises a rail, and the conveying element has a roller that rolls along the rail; The transportation system of claim 1 .
10. The conveying element has at least one roller on each side of the rail, 10. The transportation system of claim 9.
11. one of the conveying element and the transport element comprises a slot, and the other of the conveying element and the transport element comprises a pin extending into the slot to allow relative movement of the conveying element with respect to the transport element in the transverse direction; The transportation system of claim 1 .
12. two of the transport units together form a transport unit pair, the transport unit pair moving synchronously along the guide track with a predetermined gap maintained between the two transport units; The transportation system of claim 1 .
13. The predetermined gap is defined between the conveying elements of the pair of transport units; 13. The transportation system of claim 12.
14. the first guide track has straight and curved track segments, and the control unit is configured to control the linear motor to decelerate the transport unit at a transition from a straight track segment to a curved track segment and to accelerate the transport unit at a transition from a curved track segment to a straight track segment; 13. The transportation system of claim 12.
15. 1. A method of operating a transportation system, the transportation system comprising: a plurality of linear motors arranged in a row and having a first guide track; a curved second guide track, the second guide track having a constant curvature; At least one transport unit having a transport element movable along the first guide track in a moving direction by the linear motor, and a transport element configured to be moved in the moving direction together with the transport element when the transport element moves along the first guide track, wherein the transport element is movable relative to the transport element in a transverse direction extending transversely to the moving direction, and the transport element is guided in the second guide track; a control unit, wherein the method comprises: controlling the linear motor to move the transport unit along the first guide track; A method comprising:
16. The method of claim 15 , wherein the transportation system is a multi-carrier system.
17. the transport system comprises at least two of the transport units that together form a transport unit pair, and the method comprises: controlling the linear motors to synchronously move the pair of transport units along the guide track while maintaining a predetermined gap between the two transport units; The method of claim 15, comprising:
18. the transport system comprises at least two of the transport units that together form a transport unit pair, and the method comprises: controlling the linear motors to synchronously move the pair of transport units along the guide track while maintaining a predetermined gap between the conveying elements of the pair of transport units; The method of claim 15, comprising:
19. the first guide track has linear and curved track segments, and the method further comprises: controlling the linear motor to decelerate the transport unit at transitions from straight track segments to curved track segments and to accelerate the transport unit at transitions from curved track segments to straight track segments; The method of claim 15, comprising: