Conveying system and method for operating a conveying system with collision monitoring

Abstract

In order to allow a safe change of the movement limit or of the size of the movers in the conveying system (1) in the form of a long-stator linear motor during operation of the conveying system (1), it is provided that during operation of the conveying system (1) a new movement limit or a new size is predetermined for a first conveying unit (Tn) and it is checked whether the new movement limit or the new size leads to a risk of collision with another adjacent conveying unit (Tn) or with a barrier (B) of the conveying system (1) due to a predetermined collision logic and if no risk of collision is identified, the new movement limit is used as a collision movement limit for the first conveying unit (Tn) in the collision logic or the new size is used as a collision size for the first conveying unit (Tn) in the collision logic.

Description

Technical Field

[0001] This invention relates to a method for operating a conveyor system in the form of a long stator linear motor having multiple conveying units. During operation of the conveyor system, a predetermined collision logic continuously monitors whether the distance between adjacent conveying units or between a conveying unit and a barrier is sufficiently large, thereby preventing collisions between adjacent conveying units or between a conveying unit and a barrier, taking into account predetermined collision dimensions of the multiple conveying units (adjacent conveying units) or a single conveying unit and predetermined collision movement limits. The invention also relates to a conveyor system in the form of a long stator linear motor having multiple conveying units and a system control unit for controlling the movement of the conveying units. The collision control unit is configured to continuously monitor whether the distance between adjacent conveying units or between a conveying unit and a barrier is sufficiently large during operation of the conveyor system via a predetermined collision logic, thereby preventing collisions between adjacent conveying units or between a conveying unit and a barrier, taking into account predetermined collision dimensions of the multiple conveying units or a single conveying unit and predetermined collision movement limits. Background Technology

[0002] In a linear motor, there is a main component (stator) and a secondary component (mover), the secondary component being arranged to be movable relative to the main component. A magnetic field generating unit is arranged on the main component, while an excitation magnet is arranged on the secondary component; or vice versa. The excitation magnet is designed as a permanent magnet, an electric coil, or a short-circuited winding. The magnetic field generating unit can be designed as a drive coil. The drive coil is an energized electric coil used to generate an electromagnetic field by applying a coil voltage. However, the magnetic field generating unit can also be designed as a movable magnet (permanent magnet) to generate an electromagnetic field, for example, as described in EP 3 582 376A1. Due to the interaction of the (electro)magnetic fields of the excitation magnet and the magnetic field generating unit, a force acts on the secondary component, causing it to move relative to the main component. The linear motor can be designed as, for example, a synchronous motor or an asynchronous motor. The magnetic field generating unit of the linear motor is arranged along the direction of movement or in a plane of movement. The secondary component can move along this direction of movement or move freely in both directions within the plane of movement. There are also differences between short stator linear motors and long stator linear motors. In long stator linear motors, the auxiliary components are shorter or smaller than the main components, while in short stator linear motors, the main components are shorter or smaller than the auxiliary components.

[0003] This invention relates to long stator linear motors, specifically including linear long stator linear motors (having movement in one direction of movement) and planar long stator linear motors (having movement in a plane of movement, often also referred to as planar motors). In long stator linear motors, multiple sub-components typically move simultaneously and independently of each other along the main component (either in the direction of movement or in the plane of movement). Long stator linear motors are therefore frequently used in electromagnetic conveying systems, where multiple conveying units (sub-components) for performing conveying tasks move simultaneously along the stator (main component). The movement of each conveying unit can be independent of each other.

[0004] Long-stator linear motors are known prior art. In long-stator linear motors, magnetic field generating units are arranged sequentially along a support structure in the direction of movement or in a plane of movement. In the case of planar motors, the arrangement of magnetic field generating units is also known, wherein each magnetic field generating unit is arranged on a stator in multiple planes, and multiple magnetic field generating units in one plane can be used for one direction of movement. The magnetic field generating units arranged on the support structure form the stator of the long-stator linear motor, which extends in the movement space of the conveying system. An excitation magnet, whether a permanent magnet or an electromagnet, is arranged on the mover and generates a magnetic excitation field. In the conveying system, the mover functions as a conveying unit, for example, for moving an object. If a drive coil is energized in the region of the mover, an electromagnetic drive magnetic field is generated, which interacts with the excitation field of the excitation magnet to generate a driving force on the mover. The same effect can be achieved by using a moving magnet as a magnetic field generating unit by means of which the drive magnetic field is generated. By controlling the energization of the drive coil or the movement of the magnet, a moving drive magnetic field can be generated, which allows the mover to move in the direction of movement or in the plane of movement of the long stator linear motor. The advantage is that a large number of movers can move independently of each other on the stator simultaneously, and the movement of each mover along the stator can be controlled individually and independently by means of control. For this purpose, the magnetic field generating units can be controlled individually or in groups.

[0005] Because each mover can move individually and independently on the stator, collision avoidance is known. The purpose of collision avoidance is to prevent unwanted collisions between two movers with overlapping movement paths or between a mover and another part of the conveying system, such as part of a processing station located on the conveying system. Overlapping movement paths can occur in linear motors with long stators when two movers move sequentially in the same direction or when they approach each other. Such collision avoidance can be found, for example, in EP3 202 612 A1. For this collision avoidance, it is continuously checked whether the conveying unit can perform a stationary maneuver with predetermined kinematics without the risk of colliding with a forward-driven conveying unit or a stationary barrier. It can also be checked whether the movement of the mover can be altered by adjusting the maneuver to avoid stationary maneuvers.

[0006] EP 3 196 719 A2 also describes collision avoidance in long stator linear motors. In this case, a minimum collision avoidance distance is set for each mover, and it is ensured that no other mover enters that collision avoidance distance.

[0007] Well-known collision avoidance strategies utilize knowledge of the mover's expansion in the direction of movement and its current state of motion (specifically, position, velocity, and acceleration) to detect potential collisions with other movers in the surrounding environment and intervene in movement as necessary to avoid a collision. This also requires knowledge of possible movement constraints on the mover, such as acceleration constraints (in the sense of deceleration and / or acceleration) or velocity constraints, as these constraints naturally limit possible interventions in the mover's movement and therefore also limit the likelihood of reacting to a potential collision. For example, the maximum possible deceleration has a significant impact on the mover's possible braking distance. Such movement constraints are configured in the control of long-stator linear motors or in controlled collision avoidance, and are therefore known.

[0008] However, when operating a conveyor system in the form of a long-stator linear motor, movement limits may need to be altered. For example, it may be necessary to reduce the distance between movers that drive each other at the same speed to achieve higher conveying capacity. It may be necessary to adjust acceleration limits so that collision avoidance can respond to shorter distances and, if necessary, prevent collisions. It may also occur, for example, because the production system integrated with the conveyor system has changed, or because the products being conveyed have changed, that the movers must brake more gently than before. The conveyor system may also need to be stopped, in which case the conveyor system is typically designed to stop with movement limits different from those predetermined in normal operation. Furthermore, there are certainly many other reasons that may arise to change the movement limits of the movers in a conveyor system in the form of a long-stator linear motor.

[0009] Similarly, the dimensions of the movers may change during the operation of a conveyor system, particularly expanding in the direction of movement, but also changing laterally. This can happen, for example, when the movers are loading or unloading products to be conveyed. Adjusting the dimensions to the loading state can minimize the distance between the movers, thereby increasing the conveying capacity of the conveyor system or improving the utilization rate of the processing station. Furthermore, there are certainly many other reasons for changing the dimensions of the movers in a conveyor system.

[0010] However, such changes during operation are problematic because they could cause collision avoidance to identify a collision risk after the change and thus intervene in the movement of the mover. In the worst case, collision avoidance could also trigger an erroneous response or an emergency stop of one or more movers, which is to be avoided during the operation of the conveyor system. For example, such an emergency stop could simply propagate throughout the conveyor system and cause the entire system to come to a standstill. Summary of the Invention

[0011] Therefore, the object of the present invention is to allow for the safe alteration of the movement limit or size of the mover in a conveying system in the form of a long stator linear motor during operation of the conveying system.

[0012] This objective is achieved by the following: if a new movement limit or a new size is specified for a first conveyor unit during conveyor system operation, before using the new movement limit as a collision movement limit or the new size as a collision size in the collision logic, it is checked whether the new movement limit or the new size poses a risk of collision with another adjacent conveyor unit or with a barrier of the conveyor system due to a predetermined collision logic. If no collision risk is identified, the new movement limit is used as the collision movement limit for the first conveyor unit in the collision logic, or the new size is used as the collision size for the first conveyor unit. This prevents unpredictable states of the conveyor system due to changes in collision size or collision movement limits, which could trigger undesirable responses from the collision monitoring system. A changed collision size or changed collision movement limit is only adopted if no collision risk is identified.

[0013] If the collision risk is checked repeatedly at predetermined time intervals when the collision risk of adjacent conveying units is identified, the adoption can be carried out immediately after the collision risk is eliminated.

[0014] In cases where a collision risk is identified, it is also advantageous to first modify the movement of the first and / or another conveyor unit so that the collision risk is eliminated when a new movement limit is used as the collision movement limit for the first conveyor unit, or when a new size is used as the collision size for the first conveyor unit. Only in this way is the new movement limit or the new size used as the collision size for the first conveyor unit incorporated into the collision logic. If necessary, this allows for proactive intervention in the movement before adopting the modified collision size or modified collision movement limit, so that the adoption can be carried out as soon as possible. Attached Figure Description

[0015] In the following text, reference will be made to Figure 1 To describe the invention in more detail, Figure 1 Illustrative and non-limiting advantageous embodiments of the invention are shown by way of example. In the accompanying drawings:

[0016] Figure 1 This is a possible configuration for a conveying system in the form of a linear motor with a long linear stator. Detailed Implementation

[0017] The structure and function of long stator linear motors are well-known, which is why the following references only. Figure 1 A brief description is given, and only to the extent necessary to understand the invention. Although the invention is described with reference to linear long stator linear motors, this description is equally applicable to planar long stator linear motors.

[0018] Figure 1 A conveying system 1 in the form of a linear motor with a long linear stator is shown, having a normally stationary stator 2 (the main component of the motor), and a large number of conveying units T1 to Tn (secondary components of the motor) that can move along the stator 2. Here, n is used as an index to facilitate differentiation between the conveying units Tn. Of course, the conveying units Tn need not have the same design, but can be different, particularly in their dimensions or in terms of their possible movement.

[0019] The stator 2 can also consist of multiple conveying paths P1, P2, wherein each conveying unit Tn is capable of moving on various conveying paths P1, P2. For this purpose, conveying paths P1, P2 can be connected to each other via interchanges (turnouts, switches) W, and conveying units Tn can be switched from one conveying path P1, P2 to another at interchanges W1, W2. Conveying paths P1, P2 can be closed or open paths. By arranging conveying paths P1, P2 in a desired manner, a conveying system 1 with different movement spaces for the conveying units Tn can be implemented very easily and flexibly. This movement space is not limited to a plane (e.g., a plane). Figure 1 (A simple example in the text), but it can also be extended freely in space.

[0020] The magnetic field generating unit 3 is arranged along the stator 2. The magnetic field generating unit 3 can be in the form of a drive coil, but it can also be in the form of a moving permanent magnet. For clarity, in Figure 1 Only some magnetic field generating units 3 are shown in the figure.

[0021] The stator 2 can also be configured as stator segments Sm, wherein multiple magnetic field generating units 3 are arranged on each stator segment Sm. The stator segments Sm are arranged side by side or sequentially, and can have different geometries, such as straight segments, different curved segments, adapter segments, etc.

[0022] An excitation magnet 4, typically a permanent magnet arrangement but also in the form of an electromagnet, is arranged on each conveying unit Tn, generating an excitation magnetic field. To move the conveying unit Tn, the excitation magnetic field of the conveying unit Tn interacts with the driving magnetic field generated by the magnetic field generating unit 3 in the region of the conveying unit Tn. The number of magnetic field generating units 3 used to generate the driving magnetic field is irrelevant. For example, a driving voltage is applied to a driving coil, which serves as a magnetic field generating unit 3, to generate the desired driving magnetic field. Alternatively, the permanent magnet, which serves as a magnetic field generating unit 3, is moved to generate the desired driving magnetic field. To move the conveying unit Tn, the driving magnetic field is moved in the moving direction by appropriately controlling the magnetic field generating units 3. Through the interaction of the driving magnetic field and the excitation magnetic field, a force can be generated on the conveying unit Tn in the moving direction (or opposite to the moving direction) (or, in the case of a planar long stator linear motor, in both directions in the moving plane), but a force orthogonal to the conveying unit can also be generated. Such a normal force can be used in adapters W1 and W2 to steer the conveying unit Tn onto the desired conveying paths P1 and P2 to guide the conveying unit Tn on the stator 2 (e.g., a floating conveying unit Tn of a planar long stator linear motor), but it can also hold the conveying unit Tn on the stator 2. It can also be used to generate torque in all spatial directions on the conveying device Tn. The principle of this motor is well known.

[0023] like Figure 1 As shown, the excitation magnet 4 can also be arranged on both sides of the conveying unit Tn so as to interact with the magnetic field generating unit 3 on both sides of the conveying unit Tn. This can be provided, for example, in the adapters W1 and W2. However, the force can also be increased, especially in the direction of movement.

[0024] A processing station 5 can also be provided along the stator 2 of the conveying system 1 to process or manipulate the product 6 conveyed by the conveying unit Tn. The product 6 can be held on the conveying unit Tn during processing, and the conveying unit Tn can be stopped or moved during processing. However, the product 6 can also be removed from the conveying unit Tn for processing, and after processing, the product 6 can be placed back on the conveying unit Tn or on another conveying unit to continue moving. A transfer station 7 can also be provided independently of the processing station 5 to place the product 6 on the conveying unit Tn for continued conveying in the conveying system 1 (e.g., for feeding products into the conveying system 1) and / or to remove the product 6 from the conveying unit Tn (e.g., after processing has been completed). A manipulation device 8, such as a robot, can be provided for this purpose. The product 6 can be placed or removed when the conveying unit Tn is stationary or when the conveying unit Tn is moving.

[0025] System control unit 10 is configured to control the movement of conveying units Tn of conveying system 1. System control unit 10 specifically controls magnetic field generating unit 3 to implement the desired movement of conveying units Tn. The desired movement of conveying units Tn is typically predetermined, for example, based on a movement plan. At each time step of the movement control of conveying units Tn, typically within a range of 10 or 100 milliseconds, a movement setpoint for each conveying unit Tn is known, such as a set position or set speed. System control unit 10 determines a control signal from this set position / set speed, which is then executed (implemented) by magnetic field generating unit 3 interacting with the corresponding conveying unit Tn. The control signal is, for example, the coil voltage of a drive coil, which can then be generated by power electronics and applied to the drive coil. To determine the control signal, the current position of the conveying unit Tn on stator 2 can also be determined, for example, as the actual position of the conveying unit Tn, and made available to system control unit 10 for control of movement. For this purpose, position sensors can also be arranged along stator 2 in a well-known manner to detect the position of the conveying units Tn.

[0026] The system control unit 10 can also be designed as a distributed control system with multiple control units working together. For example, multiple section control units 11 are provided, each responsible for a specific part of the stator 2. Individual section control units 11 can also be configured, for example, via... Figure 1 The data buses 12 shown are interconnected to allow for the exchange of required data. In addition to the section control unit 11, the system control unit 10 may also include a higher-level control unit 13, which, for example, generates setpoints for the movement of the transport units Tn, and may also implement collision logic 14 to prevent collisions between the transport units Tn. However, this collision logic 14 can also be implemented in a separate collision control unit 15 (as in...). Figure 1 In the example, the control unit can also be connected to other control units of the system control unit 10, for example, via the data bus 12. The collision control unit 15 can be part of the system control unit 10. Other components of the conveying system 1 can also be connected to the system control unit 10 via the data bus 12, such as the control unit of the manipulating (transporting) device 8 (e.g., Figure 1 (as shown by the dashed line in the diagram) or the control unit of processing station 5.

[0027] Control units (e.g., system control units, section control units, higher-level control units, collision control units, control units of manipulators or processing stations) are typically implemented as microprocessor-based hardware, such as computers, microcontrollers, programmable logic controllers, etc. Suitable control software is executed on the microprocessor-based hardware in a known manner to achieve the desired function. The hardware may have suitable interfaces to achieve the desired function. However, embodiments as integrated circuit control units are also conceivable, such as field-programmable gate arrays (FPGAs) or application-specific integrated circuits (ASICs). Hybrid forms are also conceivable.

[0028] The collision logic 14 of the system control unit 10 is typically in the form of collision software, using predetermined, such as programmed or configured criteria, to check for the risk that a conveyor unit Tn will collide with an adjacent conveyor unit Tn-1 or the barrier B of the conveyor system 1 due to its movement. The adjacent conveyor unit Tn-1 can be a conveyor unit Tn-1 driven in front of or behind the conveyor unit Tn (regardless of its direction of movement) (especially in the case of a linear long stator linear motor, but also in the case of a planar long stator linear motor), or a conveyor unit Tn-1 driven next to the conveyor unit Tn (especially in the case of a planar long stator linear motor, or in the area of ​​the adapter W). The barrier B of the conveyor system 1 can, for example, be part of the path of the conveyor unit Tn that is blocked. An example of this is a door at processing station 5 that is closed when another conveyor unit Tn is inside. On the other hand, an open door is not a barrier B. However, the barrier B is only logically present in the system control. For example, when a transport unit Tn is currently located in a switch (exchange, turnout, switch) W, this logical barrier B can be used to block other transport units from entering the switch area. However, this logical barrier B can also be used to implement areas with speed or acceleration restrictions. In this case, barrier B, for example, prevents the transport unit Tn from entering the speed-restricted area at a speed exceeding the defined maximum speed.

[0029] Collision logic 14 specifically checks the distance A between adjacent conveyor units Tn, Tn-1 or between conveyor unit Tn and barrier B in the direction of movement (in the case of a planar motor, this means both directions of movement, or laterally to the direction of movement in the area of ​​adapter W), and assesses whether distance A is sufficient to change the movement of conveyor units Tn, Tn-1 in the event of an error to avoid a collision. This change in movement can be achieved, for example, by stopping conveyor units Tn, Tn-1 with a predetermined maximum deceleration (acceleration limit) or by reducing the current speed to a predetermined lower speed with a predetermined deceleration. Other changes in movement can also be envisioned, such as changes in direction on a planar long stator linear motor. For this purpose, a collision distance K in the direction of movement (in the case of a planar motor, this means both directions of movement, or laterally to the direction of movement in the area of ​​adapter W) can be predetermined between two adjacent conveyor units Tn, Tn-1 or between conveyor unit Tn and barrier B, and this distance must not be lower than this distance; otherwise, movement can no longer be adjusted to avoid a collision.

[0030] Distance A is obtained from the collision dimensions of conveying units Tn and Tn-1 and the current positions of adjacent conveying units Tn and Tn-1 on stator 2. The current position can be determined using a position sensor, or it can be determined in the system control unit 10, or it can simply be a pre-determined set value for the position. The collision dimensions are obtained from the geometry of conveying units Tn and Tn-1. Based on... Figure 1 In the embodiments, the collision dimensions are given by the length L and width b of the conveyor units Tn, Tn-1. The collision dimensions can be real values ​​obtained directly from the geometry of the respective conveyor units Tn, Tn-1, but can also be purely logical values, for example, by placing a simple geometry (e.g., a rectangle) around the conveyor units Tn, Tn-1 that defines the collision dimensions, at least around the collision-related region of the conveyor units Tn, Tn-1. This simplifies the calculation of distance A. On a straight extension of a long stator linear motor, the collision dimensions in the direction of movement may be sufficient to determine distance A. In bends, or in the adapter W, the collision dimensions transverse to the direction of movement may also be important, as the conveyor units Tn, Tn-1 can deflect at both ends of the bend, and the distance can decrease radially inward. The collision dimensions of the conveyor units Tn, Tn-1 required for collision logic 14 can in any case be assumed to be known.

[0031] The collision distance K, distance A, and position are naturally related to the specific reference points of the conveying units Tn and Tn-1, such as the centers of the conveying units Tn and Tn-1 (e.g., ...). Figure 1 ) or its front or back end (each is viewed in the direction of movement).

[0032] The collision distance K depends on the current movement state of the conveyor units Tn and Tn-1, particularly their speed and acceleration. The collision distance K is selected or predetermined so that collisions can be avoided by intervening in the movement of adjacent conveyor units Tn and Tn-1, or conveyor unit Tn (in the case of barrier B). Predetermined collision movement limits also play a crucial role in determining the collision distance K, as this determines how to intervene in the movement of conveyor units Tn and Tn-1, such as braking with maximum deceleration (acceleration limit) or potentially accelerating to maximum speed with maximum acceleration (speed limit). The collision distance K can be configured, for example, via collision logic 14, but can also be continuously adjusted during operation.

[0033] Therefore, during the operation of the conveying system 1, taking into account predetermined collision movement limits and given collision dimensions of conveying units Tn, Tn-1, predetermined collision logic 14 continuously monitors whether the distance A between adjacent conveying units Tn, Tn-1 or between conveying unit Tn and barrier B on stator 2 is sufficiently large to prevent collisions between adjacent conveying units Tn, Tn-1 or between conveying unit Tn and barrier B. The collision movement limits determine how the movement of conveying units Tn, Tn-1 should be changed if necessary, for example, by the maximum deceleration that can be used for braking. This check is performed in time steps of collision control, typically in the range of 10 to 100 milliseconds, preferably corresponding to the time step for adjusting the movement of conveying unit Tn.

[0034] Given predetermined boundary conditions (collision movement limits, collision size, and involved transport units Tn and Tn-1), a collision distance K can be determined and remains unchanged if the boundary conditions remain constant. The collision distance K may differ for different combinations of transport units Tn and Tn-1, but this will not alter the basic procedure. If the boundary conditions change, the collision distance K can be redefined. This can be accomplished through simple kinematic calculations.

[0035] Since the collision distance K depends on the collision size and collision movement limits of the (multiple) conveyor units Tn and Tn-1 involved, changes in the collision size or collision movement limits can lead to unexpected conditions on conveyor system 1. In the worst case, this could result in a collision or an emergency stop of part or even the entire conveyor system 1. This is illustrated using the following striking example, although other examples are possible.

[0036] The collision size of the conveyor unit Tn increases in the direction of movement, for example, because a specific product 6 is placed on the conveyor unit Tn and the product extends beyond the front edge of the conveyor unit Tn, such as... Figure 1The dashed line on the middle conveyor unit T1 is shown. This will cause the distance to the conveyor unit Tn-1 moving forward in the same direction of movement, or the distance to the barrier B in front of it, or the distance A to the conveyor unit Tn-1 moving towards the conveyor unit Tn, to decrease, because distance A depends on the collision size. In this case, the collision distance K between the two conveyor units Tn, Tn-1 or to the barrier B may not be reached.

[0037] For example, since a specific product 6 is placed on conveyor unit Tn, the collision size of conveyor unit Tn increases against the direction of movement. This will cause the distance A to the rear-driven conveyor unit Tn-1, or to the barrier B located behind it, or to the conveyor unit Tn-1 driven away from conveyor unit Tn, to decrease, because distance A depends on the collision size. In this case, the collision distance K between the two conveyor units Tn, Tn-1, or to the barrier B may not be reached.

[0038] If product 6 protrudes laterally (as well as...) Figure 1 As shown, the same situation may occur, especially in the case of planar long stator linear motors. Lateral expansion can also lead to a reduction in the distance A in the bend of the linear long stator linear motor or in the adapter W.

[0039] The maximum deceleration of the conveyor unit Tn increases. For example, if the forward-driven conveyor unit Tn is braked at this increased maximum deceleration, the distance A from the adjacent conveyor unit Tn-1 may become too small.

[0040] The maximum deceleration of the conveyor unit Tn decreases. For example, if the conveyor unit Tn is braked at this reduced maximum deceleration, and thus the braking distance becomes longer, the distance A from the forward-driving conveyor unit Tn-1 may become too small. The same applies to the case of barrier B, where the distance A to the barrier may become too small.

[0041] In principle, collision avoidance issues arise particularly when the braking distance of the forward-driven conveyor unit Tn is shortened due to changes in movement restrictions, or when the braking distance of the rear-driven conveyor unit Tn is lengthened.

[0042] To avoid this situation when a new movement restriction or new size is specified for a conveyor unit Tn during the operation of the conveyor system 1, the procedure is as follows: Check whether the new movement restriction or size results in a risk of collision with an adjacent conveyor unit Tn-1 or with barrier B. This could be a conveyor unit Tn-1 that is driven in the front, rear, or opposite directions. In the case of a planar long stator linear motor, both directions of movement must, of course, be checked. However, the new movement restriction or new size is initially stored only in the system control unit 10 and is not immediately adopted by the collision logic 14. The collision logic 14 checks whether a risk of collision with another conveyor unit Tn-1 or with barrier B is identified when the new movement restriction is used as the collision movement restriction for the first conveyor unit Tn or when the new size is used as the collision size for the first conveyor unit Tn. This can be easily accomplished using criteria predetermined in the collision logic 14 for checking collision risks, where the new size or new movement restriction is assumed for the check, for example, for determining distance A or collision distance K. If no collision risk is identified, a new movement limit is adopted as the new collision movement limit for the transport unit Tn, or a new size is used as the collision size for the transport unit 14 and used in the collision logic 14 from this point onwards (until any possible new changes).

[0043] The check can be repeated, for example, at each time step of the check, until the new size or movement restriction can be adopted. If the movement of adjacent conveyor units Tn, Tn-1 does not change, it is possible that the new size or movement restriction will not be adopted at all. However, this is unlikely, especially when conveyor system 1 has long or multiple movement paths P1, P2 and multiple conveyor units Tn.

[0044] If the system controller 10 allows, it is also possible to try to change the movement of at least one of the adjacent conveying units Tn, Tn-1, thereby allowing for the adoption of new dimensions or new movement restrictions.

[0045] If collision logic 14 identifies a collision risk, it can therefore first modify the movement of conveyor unit Tn and / or, if necessary, modify the movement of adjacent conveyor unit Tn-1, thereby eliminating the collision risk when a new movement limit is used as the collision movement limit for the first conveyor unit Tn, or when a new size is used as the collision size. When the adjustment of the movement means that a collision risk is no longer identified, in collision logic 14, the new movement limit is used only as the collision movement limit for the first conveyor unit Tn, or the new size is used as the collision size for the first conveyor unit Tn, to avoid collision.

[0046] This collision risk check can be performed by collision logic 14 at each time step of collision control, or it can be performed at longer time intervals (e.g., integer multiples of the time steps of collision control).

[0047] In the event of a change in the collision size of the conveying unit Tn, particularly an increase, it is advantageous to make the change in the system control unit 10 before the actual change is made on the conveying system 1, i.e., before the product 6 is actually placed on the conveying unit Tn. Therefore, it is possible that when an actual change occurs on the conveying system 1, the collision logic 14 is already operating with the new collision size.

[0048] Changes to the collision size or collision movement limit of the transport unit Tn can be initiated by the user, but can also be performed by the system control unit 10, such as the higher-level control unit 13. For example, the user can easily adjust the safe distance between transport units Tn and Tn-1 or to barrier B via the collision size. If the movement command of the transport unit Tn is replaced by another movement command with different collision movement limits, a change in the system control unit 10 may occur.

Claims

1. A method for operating a conveying system (1) having multiple conveying units (Tn) in the form of a long stator linear motor, wherein, During operation of the conveying system (1), a predetermined collision logic (14) continuously monitors whether the distance (A) between adjacent conveying units (Tn) or between a conveying unit (Tn) and a barrier (B) is sufficiently large to prevent collisions between adjacent conveying units (Tn) or between a conveying unit (Tn) and the barrier (B), taking into account predetermined collision movement limits and predetermined collision dimensions of the conveying unit (Tn) or the plurality of conveying units (Tn). The system is characterized in that, during operation of the conveying system (1), a new movement limit or a new dimension is specified for the first conveying unit (Tn). Before using the new movement limit as a collision movement limit or the new size as a collision size in the collision logic (14), it is checked whether the new movement limit or the new size will cause a risk of collision with another adjacent conveying unit (Tn) or with the barrier (B) of the conveying system (1) due to the predetermined collision logic, and wherein, if no risk of collision is identified, the new movement limit is used as a collision movement limit for the first conveying unit (Tn) in the collision logic, or the new size is used as a collision size for the first conveying unit (Tn) in the collision logic.

2. The method according to claim 1, characterized in that, When a collision risk is identified between the adjacent transport unit (Tn) or between the transport unit (Tn) and the barrier (B), the collision risk is checked repeatedly at predetermined time intervals.

3. The method according to claim 1, characterized in that, If a collision risk is identified, the movement of the first conveying unit and / or the other conveying unit (Tn) is first modified so that the collision risk is eliminated when the new movement limit is used as the collision movement limit of the first conveying unit (Tn) or when the new size is used as the collision size of the first conveying unit (Tn). Only in this way is the new movement limit used as the collision movement limit of the first conveying unit (Tn) or the new size used as the collision size of the first conveying unit (Tn) in the collision logic.

4. A conveying system, said conveying system being in the form of a long stator linear motor, having a plurality of conveying units (Tn) and a system control unit (10) for controlling the movement of said conveying units (Tn), wherein, The collision control unit (15) is configured to continuously monitor, by means of predetermined collision logic (14), during operation of the conveying system (1) that the distance (A) between adjacent conveying units (Tn) or between a conveying unit (Tn) and a barrier (B) is sufficiently large, thereby preventing collisions between adjacent conveying units (Tn) or between a conveying unit (Tn) and the barrier (B), taking into account predetermined collision movement limits and predetermined collision dimensions of the conveying units (Tn) or the plurality of conveying units (Tn). The unit is characterized in that, during operation of the conveying system (1), a new movement limit or a new dimension can be specified for the first conveying unit (Tn), and... Before using the new movement limit as the collision movement limit or the new size as the collision size in the collision logic (14), the collision control unit (15) checks whether the new movement limit or the new size will cause a risk of collision with another adjacent conveyor unit (Tn) or with the barrier (B) of the conveyor system (1) due to the predetermined collision logic (14), and where there is no risk of collision, the collision logic (14) adopts the new movement limit as the collision movement limit of the first conveyor unit (Tn), or adopts the new size as the collision size of the first conveyor unit (Tn) in the collision logic (14).

5. The conveying system according to claim 4, characterized in that, Upon identifying a collision risk, the system control unit (10) first changes the movement of the first conveying unit and / or the other conveying unit (Tn) so as to eliminate the collision risk when the new movement limit is used as the collision movement limit of the first conveying unit (Tn) or when the new size is used as the collision size of the first conveying unit (Tn). Only in this way does the collision logic use the new movement limit as the collision movement limit of the first conveying unit (Tn) or use the new size as the collision size of the first conveying unit (Tn).

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