HK1217685B - Decentralized linear motor regulation for transport systems - Google Patents

Description

Distributed linear motor regulation for transport systems

Technical Field

The present invention relates to an electric linear drive arrangement, in particular for a moving walkway (Fahrsteige) or other transport device for transporting persons or objects. The electric linear drive arrangement comprises, as an active main part, a long stator (Langstator) moving in a direction of movement and a plurality of passive secondary parts which are movable relative to the main part and are arranged one after the other in the direction of movement, the long stator having several successive long stator segments in the form of coil sets in the direction of movement. The invention also relates to a method for operating an electric linear drive arrangement for moving a secondary part in a non-uniform manner.

Background

For transporting people, such moving walkways are known: in order to bridge large distances in a relatively short time, the moving walkway has a variable speed over its length. In order to allow easy access for the transported person, the end of the moving walkway is moved at a first, lower speed. After the entrance area, the moving walkway, which is usually formed by a single moving walkway plate, is accelerated to a higher second transport speed, after which a further deceleration to a lower speed (e.g. a first speed) is performed at the exit area. In practice, a velocity of, for example, 0.6m/s may be provided for the inlet and outlet regions, while the higher second velocity is 2 m/s.

In order to achieve the described speed change along the length of the moving walkway, the moving walkway plate must be movable in a telescopic manner with respect to the other moving walkway plate. In order to achieve driving at acceleration and different speeds, known practices are: the moving walkway plates are driven in the entry and exit areas by means of a worm screw (Schnecke) with variable pitch (Steigung). Then, the moving walkway plate is accelerated to and decelerated from the second speed using such a worm; and a chain moving at a second, higher speed is provided between the worms.

Mechanically driven moving walkways with variable speed are known from EP 1253101B 1, EP 1300359B 1, EP 1582494B 1, EP 1939127B 1, EP 1939128 a2, EP 1939129B 1 and EP 1939130B 1. Even though the moving walkways described have proven themselves in practice, there is still a need for a simplified design. Specifically, the mechanical drive requires a relatively complicated arrangement, and thus the amount of maintenance common to the mechanical drive also increases.

EP 1258447B 1 and EP 1502891B 1 disclose a drive arrangement, in particular such a moving walkway: single step in the form of a moving walkway step or moving walkway plateProvided with its own electric drive. This leads firstly to the following benefits: the central drive train in the form of an endless chain or the like may be omitted. Furthermore, EP 1258447B 1 also proposes moving the moving walkway at an increased speed on the return transport path, which results in that the number of moving walkway plates can be reduced as a whole. However, the assembly of the motor itself for moving the walkway plates is associated with considerable overall costs (Aufwaden).

The invention is based on an electrically powered linear drive arrangement known in practice. The linear drive arrangement has a coil group as an active main part arranged one after the other in a stationary manner along a movement direction, and a plurality of movable secondary parts in the form of permanent magnets. Using a plurality of current transformers (Umrichter) for sectionalizing the power supply for the stationary coil assembly, the position of the secondary part, the feed forceAnd the motor current through the coil assembly is controlled by a central regulator (Regler) through the corresponding current transformer. In this case, it is known in practice to use an absolute sensor arranged on the secondary part to detect the position, so as to mark, for example, a magnetic strip detected by a static sensor along the direction of movement. The central control of all long stator segments of the main part can be used to move the secondary parts in a variable manner in a manner matching each other. However, the described electric linear drive arrangement with central control of the movement of the secondary part requires a relatively complex circuit configuration.

EP 1845428 a2 discloses an electric linear drive arrangement in which the secondary parts are each fitted with two permanent magnets that interact with different primary parts or segments. The two magnets form, with the respectively assigned main part, two linear motors which are separated from one another. Thus, at the transfer point, movement is transferred from one linear motor to the other. The linear motor formed in this way is only activated alternately. A sensor may be used to determine the position of the tray fitted with two permanent magnets.

EP 2161826B 1 discloses a transmission device with a dynamically variable drive region. The primary part is subdivided into a plurality of zones with secondary parts per zone. The boundaries of the divided regions move with the secondary components dynamically, and individual secondary components may move with a predefined movement profile (bewegungsprodil). In this case, successive secondary members may move in a completely uniform manner, or in different manners from one another.

Disclosure of Invention

The present invention aims to provide an electric linear drive arrangement and a method for operating an electric linear drive arrangement which enable a simple technical configuration and which are particularly suitable for a moving walkway for transporting persons or objects.

The present invention relates to an electric linear drive arrangement, and a method for operating an electric linear drive arrangement, and thereby achieves the above-mentioned objects.

Starting from the arrangement with the features described at the outset, the electric linear drive arrangement is characterized in that: each long stator segment has its own control device for controlling the movement of the secondary part, the control device being configured to move the secondary part using control parameters specific to the respective long stator segment.

Within the scope of the invention, the secondary components are thus subject to distributed control. Thus, each long stator segment can operate autonomously with a predefined movement configuration for the secondary part stored in the memory assigned to each control device. Thus, the central control of the long stator segments and thus of the coil groups for the different long stator segments is omitted. Instead, the complete long stator is divided into a plurality of static long stator segments, each having a designated current transformer, each long stator segment having its own control device. Once the secondary component reaches the long stator segment, the secondary component moves autonomously by using the assigned control device of the stored movement configuration.

Within the scope of the invention, the following arrangements are preferably made: at each long stator segment, successive secondary parts move in the same way or at least according to the same specifications, different moving speeds can be set along the complete long stator. For example, the acceleration and deceleration sections or other regions of constant moving speed may be implemented in a single long stator section.

As mentioned above, the individual sub-components are moved in the long stator segments by means of a designated control device. In this case, the following setting may optionally be made: immediately adjacent motor segments are brought into communication with each other so that the secondary components can be transferred directly and smoothly. Immediately adjacent long stator segments may communicate with each other in a master/slave mode, e.g. if a secondary component is located at the junction of two consecutive long stator segments, a coordinated control is performed.

Within the scope of the invention, a fixed local allocation of long stator segments is performed, thereby omitting complex dynamic adjustments and allocations. The individual long stator segments operate autonomously except for communication between immediately successive long stator segments. The controller of the individual long stator segments can be set to monitor and adjust the position, speed and feed force of the individual secondary parts.

The specific configuration of the long stator segments has different possibilities. The following settings may be made: the number of long stator segments is greater than the number of sub-components. A high degree of flexibility is achieved by finely subdividing the long stator into short long stator segments. If in this case the length of all long stator segments is also shorter than the distance between successive sub-parts, the sub-parts are guided only for some of the long stator segments. In this case, the change of the movement characteristics based on the respective programs is easily implemented in a wide range.

However, in general, at least the movement configuration to be implemented next is known, for example when arranging long stator segments. If a linear drive arrangement is provided for a moving walkway, for example, for transporting people or objects, the end regions of the moving walkway are set as acceleration or deceleration sections, whereas in the middle of the moving walkway a high forward speed is advantageous. It is therefore advantageous to configure the long stator segments with different lengths according to the respective requirements. It is also advantageous here to provide long stator segments of longer length, for example if the secondary part passes through an area at high speed. The longer length also allows for the following: during faster movements, a greater distance is covered per unit time.

In addition, within the scope of the invention, it is also not necessary to guide only one sub-component precisely in each long stator segment during operation. In principle, it is also possible to move two or more subcomponents simultaneously in a long stator segment by means of a specific control device. In operation, in particular when no significant deceleration or acceleration is provided in the respective long stator segment, a plurality of secondary components can be simply guided in the long stator segment. For a moving walkway for transporting people or objects, the central section between the entrance area and the exit area may be bridged by, for example, one long stator section or a plurality of long stator sections having a relatively long length.

In this case, advantageously, at least one sensor for detecting the state of the secondary component is connected to the control device, respectively. In the simplest case, a sensor for determining the position is provided for each control device. An absolute sensor for detecting position may be realized by, for example, combining an incremental encoder and a non-contact proximity switch. Such an absolute sensor can also generate a reference index in terms of direction at the end of travel. The secondary part may also be equipped with a device for continuously determining the position, for example a magnetic strip. The feed force required to move the secondary part can be determined in a known manner by measuring the coil current or voltage.

Within the scope of the invention, the control device may be connected to a central controller; however, unlike the arrangements known in the prior art, the central controller does not control the complete movement sequence and the control of the current transformer.

In order to be able to change the complete movement sequence of the electromotive linear drive arrangement, the central controller can interact with the control device of the individual long stator segments in the following manner: the devices are controlled synchronously using a clock signal. Then the stored movement configuration for each controller is adapted to the clock signal as a time reference. If the clock frequency changes, the following settings are intended: specifically, in each long stator segment, the speed of the secondary component is varied in a proportional manner. Thus, the clock signal can be used to vary the speed of the secondary components globally along the long stator.

In addition, the central controller may also use the corresponding connection to send a start signal, a stop signal or a signal for changing the operating mode. For example, for each control device, a different movement profile for a different operating mode may be stored, and if there is a corresponding signal from the central controller, all control devices subsequently change to different operating modes simultaneously. Since the parameters for the respective operating mode are already stored for each control device, such a change can be carried out very simply and rapidly. The synchronization with the clock signal can be performed, for example, by means of a field bus system (e.g. EtherCAT). In this case, it should be taken into account that a single long stator segment (except for the optionally provided master/slave pattern of immediately successive long stator segments) does not need to relate to state variables or state information of other long stator segments.

As mentioned above, one preferred configuration of the invention provides a predefined movement configuration for the secondary part stored in a designated memory for each control device. The memory is preferably provided directly at the control device or as an integrated component of the control device, so that signal transmission from the individual control device to the remotely arranged memory can be omitted.

By convention, the term "long stator" relates to the constructive configuration of an electric linear drive arrangement. It is obvious that the invention is not limited to movements in a linear direction. Curves, bends, downhill sections, inclinations, etc. may also be provided, in particular along the direction of movement. In particular, the long stator may form a closed movement circuit for the secondary part. If the electric linear drive arrangement is part of a moving walkway for transporting people (e.g. people moving from a starting point to an ending point), then in that case the secondary component must then return to the starting point again.

Since within the scope of the invention the mechanical construction is simplified by omitting a central drive in the form of a chain or the like, with this electric linear drive arrangement it is also possible to realize a moving walkway with sections moving in opposite directions, both intended to convey people, in a particularly simple manner. Then the individual subcomponents must be transferred between the segments only in an appropriate manner.

If the secondary part is only moved between the end point and the starting point and returned in order to transport a person or object, the drive can also be performed with maximum speed in order to bridge the return area as fast as possible and with as few secondary parts as possible.

At least between the starting point and the end point for transporting a person or object, the secondary parts or elements driven by the secondary parts in the form of moving walkway plates can be mechanically guided close to each other and/or mechanically coupled to each other. Such a mechanical coupling may also avoid the formation of intermediate spaces between two successive moving walkway trays in case of failure of the linear drive arrangement. However, such a mechanical connection can be cancelled if the secondary part or an element driven by the secondary part in the form of a moving walkway plate moves between the end point and the starting point when no person or no object is conveyed. In particular, it is also possible within the scope of the invention to remove or add individual secondary components during operation. For example, individual secondary components may also be replaced during operation for maintenance purposes.

The invention relates in particular to such a linear drive arrangement using a moving walkway for transporting people or objects.

The invention also relates to a method for operating said electric linear drive arrangement, predefining different movement configurations for respective controllers for at least some of the long stator segments in order to move the secondary part in a non-uniform manner along the long stator. As mentioned above, in this case the average speed of the secondary components along the long stator may preferably be varied by the frequency of the clock signal from the central controller.

The long stator segment preferably controls the designated sub-assembly autonomously, except optionally in view of a clock signal, and a matching movement sequence may be provided for each long stator segment of the successive sub-assembly here.

Drawings

The invention is explained below using the accompanying drawings, which show only one exemplary embodiment, in which:

figure 1 shows an electric linear drive arrangement according to the prior art,

figure 2 shows a linear drive arrangement according to the invention,

figure 3A shows a moving walkway for transporting people using an electric linear drive arrangement,

figure 3B shows a velocity profile of the movement of the secondary part along the moving walkway according to figure 3A,

fig. 4 shows a possible constructional arrangement of a moving walkway for transporting people.

Detailed Description

Fig. 1 shows an electric linear drive arrangement according to the prior art known in practice with a long stator moving in the direction of movement and with individual long stator segments 1 in the form of coil groups.

The current transformers 2 for controlling the coils of the respective long stator segments 1 are each upstream of the stationary long stator segment 1. All current transformers 2 are controlled by a central controller 3 to move a plurality of secondary components (not shown in fig. 1) in the form of permanent magnets 6 along the long stator formed by the long stator segments 1 according to a predefined movement configuration. Along the long stator there are also arranged sensors 4, the signals from which sensors 4 are processed by a central controller 3.

A relatively complex connection as a whole is created, in which case the control signals are continuously transmitted from the central controller 3 to the individual converters during operation of the electric linear drive arrangement. The complete signal processing (including safety logic) is performed at the central controller 3, which in this case also stores the exact movement configuration of the secondary parts along the long stator.

In contrast, fig. 2 shows the configuration of an electric linear drive arrangement according to the invention, in which case a separate control device 5 for controlling the movement of the secondary part is provided for each long stator segment 1. The control devices 5 each include a memory that stores the movement configuration set for each path segment.

In order to move the sub-components along the respective long stator segments 1, the movements are individually controlled by a designated control device 5, the control device 5 operating in a largely autonomous manner. The similarly arranged sensors 4 according to fig. 2 are each connected to a designated control device 5 and are not connected to the central controller 3'. The central controller 3' is only provided for synchronizing the control device 5 for each long stator segment using a clock signal. In addition, the central controller 3' may also send a start signal, a stop signal or a signal for changing the operating mode. The transmission of other data is neither necessary nor provided, so that a significant simplification is achieved by distributed control. In particular, there is no need for central monitoring of the complete movement sequence of the individual secondary parts on a long stator.

Fig. 2 indicates that immediately consecutive control devices 5 may optionally be connected to each other in order to transfer the secondary parts from the long stator segment 1 to the long stator segment 1.

Fig. 3A shows a highly schematic view of the use of an electric linear drive arrangement according to the invention on a moving walkway for transporting people, where only the position of the secondary part in the form of a permanent magnet 6 along the complete moving direction is shown.

The long stator forms a closed moving loop for the secondary part, having an upper run 7 and a lower run 8. Moving walkway plates 9 (fig. 4) which are movable relative to each other are provided to the individual permanent magnets 6 as secondary components.

At point X₀And X₁The permanent magnets 6 as secondary components and thus the moving walkway plates 9 fastened to the permanent magnets 6 are accelerated from a low speed (which enables the person to come up) to a continuous transport speed in between. Moving walkway plate at point X₁And X₂At which transport speed. Subsequently, at point X, in order to allow the passenger to descend from the indicated moving walkway₂And X₃Performs deceleration.

Subsequently, in order to move the individual secondary components with permanent magnets 6 and the moving walkway plate 9 back to the inlet area, these components are at point X in the lower row 8₄And X₅At high speed, resulting in that the distance can be quickly bridged with a small number of components. Subsequently, the sub-component is again transferred to the start point X₀And is thus guided in the loop at a variable speed.

By way of example, fig. 3B shows a possible speed configuration along a full stroke.

Fig. 4 shows a possible configuration of the moving walkway plate 9 for the moving walkway for transporting people. The moving walkway plates 9 are movable relative to each other, the moving walkway plates 9 are squeezed together at a slower advancing speed and only the end sections 10 are exposed. If the speed is increased, the telescopic section 11 of the moving walkway plate 9 is gradually released, resulting in a corresponding increase in the effective length of the individual moving walkway plate 9. At least in the upper run 7, the moving walkway plates 9 are guided laterally on guide rails 12 and are preferably also anchored to each other in the direction of stretching. The single moving walkway plate 9 is also connected to the permanent magnet 6 as a secondary component of the electric linear drive arrangement. As described above, at the downstream 8, the following settings can be made: the moving walkway plates 9 can be completely separated from each other for faster movement.

Claims (12)

1. An electric linear drive arrangement, in particular a moving walkway for transporting people or objects, comprising a long stator moving along a moving direction, which works as an active main part, and a plurality of passive secondary parts, which are movable relative to the main part and are arranged one after the other along the moving direction, which long stator comprises a number of successive long stator segments (1) in the form of coil groups, wherein the long stator segments are arranged along the moving direction, characterized in that each long stator segment (1) comprises its own control device (5) for controlling the movement of the secondary parts, which control device (5) is set to move the secondary parts using control parameters specific to the respective long stator segment (1), different movement configurations being predefined for the respective control devices (5) for at least some of the long stator segments (1), in order to move the secondary components in a non-uniform manner along the long stator, the average speed of the secondary components along the long stator is varied by the frequency of the clock signal from the central controller (3').

2. Linear drive arrangement according to claim 1, characterized in that a predefined movement configuration for the secondary part is stored in a designated memory for each control device (5).

3. Linear drive arrangement according to claim 1 or 2, characterized in that the control device (5) is connected to a central controller (3 '), which central controller (3') uses a clock signal to synchronize the control device (5).

4. Linear drive arrangement according to claim 1 or 2, characterized in that the number of long stator segments (1) is larger than the number of secondary parts.

5. A linear drive arrangement according to any of claims 1 to 2, wherein the long stator forms a closed moving loop for the secondary part.

6. A linear drive arrangement according to any of claims 1 to 2, wherein each long stator segment comprises a number of coils and its own current transformer for controlling the coils.

7. A linear drive arrangement according to any of claims 1 to 2, wherein the secondary part is formed from a permanent magnet.

8. Linear drive arrangement according to any of claims 1 to 2, characterized in that at least one sensor (4) for detecting the status of the secondary component is connected to the control device (5), respectively.

9. A method for operating an electric linear drive arrangement according to any of claims 1 to 8, different movement configurations being predefined for the respective control devices (5) for at least some of the long stator segments (1) in order to move the secondary parts in a non-uniform manner along the long stator, the average speed of the secondary parts along the long stator being varied by the frequency of the clock signal from the central controller (3').

10. The method according to claim 9, the control device (5) autonomously controlling the secondary components respectively assigned to the corresponding long stator segments (1) in addition to taking into account the clock signal.

11. Method according to any one of claims 9 to 10, moving successive secondary parts along the long stator in a matching sequence of movements.

12. The method according to any one of claims 9 to 10, wherein the number of secondary components is varied.