Conveying system for an industrial manufacturing facility

Abstract

The invention relates to a conveying system for an industrial manufacturing plant, having a conveying section, which is provided with a linear conveying mechanism (27) driven in a stationary manner, in particular at least one toothed belt or chain extending in the conveying direction, wherein a component carrier (21) can be moved along the conveying section by means of the conveying mechanism (27). Here, the component carrier (21) can be connected in a form-fit to the conveying mechanism (27) and can be decoupled from the conveying mechanism (27), wherein a stationary locking unit (23) is provided at the conveying section, and wherein the locking unit (23) serves for decoupling the component carrier from the conveying mechanism (27) and for fixing the component carrier (21) in a fixed position in a work single pass. By means of the conveying system, the component carrier can be fixed at the correct position of the machining station together with the component to be machined independently of the slip and vibration of the conveying mechanism, wherein the conveying mechanism can be continued to be used for other transport tasks during the machining duration, and wherein high accelerations and decelerations can be achieved with low wear. Furthermore, by means of the locking unit, the component carrier can be transported to another section of the conveying section without the component carrier being unguided during this time.

Description

Technical Field

[0001] The present invention relates to high-performance conveying facilities for cyclic production lines, and in particular to a conveying system for industrial manufacturing facilities according to the preamble of claim 1. Background Technology

[0002] In mass production, such as automobile manufacturing, different tasks are performed at each workstation in an assembly line or takt cycle, typically semi-automatically or fully automatically. A key objective of takt cycle mass production is to keep changeover times as short as possible, since no components are processed during the transport process in between. To transport components at each workstation, they are typically placed on component carriers.

[0003] During processing, components typically must remain stationary or fixed. However, not all components are processed or transported simultaneously in a factory, and the transport paths between processing stations are often of varying lengths. This results in either the component or the underlying component carrier being decoupled from the transport system during its processing time, or the transport sections being segmented, with each processing station having its own individually controllable and, in particular, stopable section.

[0004] Horizontal transport tasks are typically carried out using friction-based chain / belt or roller conveyors, as they are an economical solution due to their simple and robust construction. However, due to the friction-based principle, these conveyors reach their limits under high acceleration or deceleration. If the acceleration or deceleration forces become too large, the frictional or force fit between the material pairs is no longer sufficient to prevent the component carrier from slipping on the load-bearing drive element. Consequently, reliable positioning of the component can no longer be guaranteed.

[0005] Another problem arises when transporting multiple components simultaneously, as the high start-up current overloads the energy supply network. Therefore, the drives of the conveying equipment, especially those for sequentially arranged sections, often start at staggered times. Since the component carrier contacts the two conveyors of the two related sections as it crosses the docking point between them, the rotational speed or velocity of the load-bearing drive elements must be synchronized to prevent slippage, which negatively impacts the entire drive and its components. This ratio is influenced by the length of the component carrier and the conveyor, and the designed travel profile. Similarly, a minimum distance must be maintained between the component carriers to avoid rear-end collisions and ensure collision-free stopping in case of malfunction.

[0006] Therefore, in the aforementioned conveying principle, the synchronization requirement and the resulting drive device dependence negatively impact the cycle time of the entire facility. Furthermore, synchronization can cause undesirable peak loads in the energy balance of the conveying system due to the accumulation of starting current.

[0007] Reference WO 2019 / 187778 A1 - Sugimoto et al. "CONVEYANCE PALLET, ANDPALLET CONVEYANCE DEVICE AND PALLET CONVEYANCE METHOD THAT USE SAME transport pallet and pallet transport device and pallet transport method using the pallet" discloses a device consisting of two interconnected conveying sections having a coupling mechanism for coupling a carrying mechanism to the corresponding conveying mechanism.

[0008] exist Figure 1 The diagram illustrates a prior art roller conveyor with a base frame 10 and six load-bearing rollers 17, the latter coupled to an electric motor drive 15 via a toothed belt 16. Arrows are drawn here visually indicating the conveying direction. In this variant, lateral guidance of the component carrier (not shown) is achieved by means of lateral actuating discs at the load-bearing rollers 17 and two guide rollers 18 on the input side, abutting against the outer side of the component carrier and aligning them. An overrun protection device 19 serves as a safety device, mechanically preventing the component carrier from overrunning in case of failure. Additional equipment for defining the position of the component carrier is typically provided, but... Figure 1 Not shown in the image.

[0009] The position detection of the component carrier is typically performed via an external sensor system 11-14. This sensor system consists of at least one holding position sensor 12, another sensor 13 that provides a signal for switching between the maximum design conveyor speed and a second, slower speed (also known as fast / slow switching), and a sensor 11 that provides a signal to shut down the drive. If the component carrier moves beyond the holding position, this is detected by the other sensor 14.

[0010] Once the signal to be sent to the workstation is given by the upper control unit, the drive starts to its maximum operating speed and only slows down when the fast / slow speed sensor reports a signal, and finally shuts down completely with the help of the last sensor signal. This approach and holding position is unusable for most fully automated operations because the position of the component carrier is often inaccurate and the drive scheme has slippage; therefore, additional definition of the processing position is necessary.

[0011] A known prior art solution to the aforementioned problem is a conveying system that drives the component carrier in segments using multiple permanent magnet synchronous linear motors arranged in a grid. In this solution, the current-carrying primary component of the synchronous motor is fixed to a stationary support structure with a fixed grid, and the secondary component, having permanent magnets, is similarly fixed to the component carrier with a fixed grid. In a variant shown, the component carrier is configured with load-bearing rollers, which in turn have laterally attached flanged discs to ensure lateral guidance. The positional information required for drive adjustment from the primary to the secondary components is provided by an external displacement measurement system, which is also used to determine the position of the component carrier. However, this solution has some drawbacks.

[0012] External displacement measurement systems are costly and susceptible to vibration, which can disrupt processes, especially in harsh manufacturing environments common in mass production, such as automotive manufacturing. The strong attraction between primary and secondary components necessitates a stable load-bearing structure, negatively impacting the structural design flexibility of the component carrier. The structurally determined open design makes ferromagnetic contamination unavoidable, leading to recurring maintenance tasks. Similarly, the flexibility of the component carrier's return path is limited. The large number of synchronous linear motors and displacement measurement technologies results in a very high procurement cost for the entire conveyor system. Summary of the Invention

[0013] The objective of this invention is to create a low-cost, flexible, and reliable high-performance conveying facility for cyclic production lines, which can transport large quantities of material between processing stations in a reliably efficient manner and with repeatable accuracy in a very short time.

[0014] The present invention presents a solution to the identified problem based on a drive principle associated with a workstation, wherein a drive element, driven by a linear conveying mechanism (toothed belt, chain, or the like), is shape-fitted to a component carrier, and its position is detected directly or indirectly by means of a displacement measurement system. Within the processing station, the component carrier is transferred indirectly or directly by feed motion to the drive element of the next station, and then to the drive element of the next section of the conveying segment.

[0015] This objective is achieved, in particular, by the conveying system according to claim 1. Here, a conveying system for industrial manufacturing facilities is proposed, comprising a conveying section equipped with a stationary, linearly driven conveying mechanism, particularly having at least one toothed belt or chain extending in the conveying direction, wherein a component carrier can move along the conveying section by means of the conveying mechanism. Here, the component carrier can be form-fitted to and decoupled from the conveying mechanism; for this purpose, a stationary locking unit is provided at the conveying section, wherein the locking unit is designed to decouple the component carrier from the conveying mechanism and to fix the component carrier in a fixed position during a single work stroke. With this conveying system, the component carrier, together with the component to be processed, can be fixed at the correct location at the processing station and independently of the slippage and vibration of the conveying mechanism, wherein the conveying mechanism can continue to be used for other transport tasks during the processing duration, and wherein high acceleration and deceleration can be achieved with low wear. Furthermore, the component carrier can be transferred to another section of the conveying section by means of the locking unit, without the component carrier becoming unguided in between.

[0016] Advantageous designs for the conveying system are given in the dependent claims. Their features and advantages can be achieved individually or in a reasonable combination.

[0017] Advantageously, the locking unit is designed to couple the component carrier to the conveying mechanism and to release the component carrier from a fixed position during a single work stroke. Thus, the component carrier can be returned to the conveying operation. By implementing coupling and release within a single stroke, the locking unit can be constructed with a single actuator, and this also ensures that release occurs along with coupling; conversely, this also applies to decoupling processes within the same single work stroke as the fixed position.

[0018] Particularly advantageously, the locking unit is designed to provide uninterrupted form-fit guidance for the component carrier during decoupling and fixing and / or coupling and releasing of the component carrier. This eliminates unwanted movement of the component carrier.

[0019] According to the invention, the conveying system comprises multiple interconnected sections of a conveying segment, each section having the aforementioned or additional statically driven linear conveying mechanism. Static locking units are arranged at the junction of two sections such that a component carrier can be selectively connected to or decoupled from either the first or second section of the conveying mechanism. The component carrier is transferred between sections, with the sections overlapping each other in the transfer area, and the component carrier is secured between its form-fitting connection to the first and second sections. Therefore, at the overlapping junction of two sections, the transfer of the component carrier, and thus the transport of goods—typically components to be processed—is safe and feasible without requiring the simultaneous conveying mechanisms of the sections. It must be ensured only that the conveying mechanism that is just decoupled stops for the process; this also applies only to the point in time when the conveying mechanism is coupled later. Thus, the starting and braking processes and the resulting operating currents can be decoupled in time, and peak loads caused by the time dependence of the process can be avoided.

[0020] In order to fix the component carrier, it is advantageous to perform a shape-fitting connection between the component carrier and the locking unit or the stationary component of the conveying section, especially the load-bearing frame of the conveying section, so that the force generated during the processing of the conveyed component is not introduced into the conveying mechanism, but into the load-bearing structure and then directly into the foundation of the manufacturing facility.

[0021] The locking unit essentially comprises a movable component, particularly a slider arranged transversely to the direction of travel of the component carrier, wherein the component is designed to be coupled or decoupled from the connection mechanism of the component carrier, particularly a pin, and wherein the component is designed to decouple or couple the drive element of the conveying mechanism from the said or other connection mechanism of the component carrier during the same movement. Since the two processes are completed by a common component, there is a necessary execution of both processes in a common single-pass operation, which improves operational safety.

[0022] Especially in the case of long conveyor sections and heavy transported goods, positioning accuracy at the point of stop is limited, particularly because inherent tolerances and vibrations of the facility cannot be adjusted or eliminated when using motion detection or position detection systems on the drive side. Therefore, the locking unit advantageously has a capture area relative to the longitudinal direction of the conveyor, wherein the capture area is designed to compensate for the positioning tolerances of the component carrier at the point of fixation and / or to compensate for the positioning tolerances of the conveyor mechanism at the point of coupling of the component carrier to the conveyor mechanism. However, here, the capture area does not exceed the positional or orientational tolerances of the component carrier in the conveying direction required by the processing procedure. This saves on separate demarcation or stop elements, especially since said demarcation or stop elements, and the component carrier and its load thereby stopped, often experience significant mechanical impulses. In an advantageous variant, the locking unit can be equipped with a damping system to absorb the mechanical shocks that occur upon locking.

[0023] The conveying system advantageously incorporates an energy storage device designed to at least partially store the kinetic energy of the component carrier during deceleration before engagement with the locking unit, and designed to release the stored energy after the component carrier is coupled to the conveying mechanism. A sensor for detecting the coupling state of the locking unit is provided at the locking unit to control the timing of energy release. This reduces peak loads from the power grid, and the energy supply system can be designed to be more cost-effective.

[0024] The conveying system advantageously features variable propulsion of the conveying mechanism, wherein this variable propulsion is controlled so that the conveying mechanism stops at the point when the component carrier is connected to the locking unit and at the point when the component carrier is coupled to the conveying mechanism. This reduces both electrical and mechanical peak loads. Attached Figure Description

[0025] An embodiment of the conveying system according to the present invention will now be described with reference to the accompanying drawings.

[0026] This is shown here: Figure 2 A three-dimensional view is shown of the conveying system (hereinafter also referred to as the conveying device) according to the present invention. Figure 3 The conveying system is shown in a detailed top view. Figure 4 A front view showing the conveyor system in a stationary, locked state, and Figure 5 A conveying system with a pivotable drive unit that engages with a component carrier is shown in a front view. Detailed Implementation

[0027] exist Figures 2 to 5In the figures, the same reference numerals 20-29 always denote the same components.

[0028] In the embodiment shown here, cycle-type transport is carried out by the reciprocating motion of a slide driven by an electric motor. Alternatively, cyclic operation is also feasible.

[0029] exist Figures 2 to 5 The conveying system shown is an advantageous design according to the subject matter of the invention. For better illustration, only a portion of the conveying system is shown, wherein... Figure 3 The arrows drawn visually indicate the transport direction. Illustrations of components (loads, such as the body-in-white in vehicle manufacturing) that form a shape-fitting contact with component carrier 21 are omitted. In a variant not shown, goods may be transported directly without a component carrier, and the goods then become their own component carrier.

[0030] All solutions shown here are based on the load-bearing roller 24 and the slider or guide slide with guide rail, which can be implemented such that the load-bearing roller or guide slide can be selectively or mixedly stationary or fixed to the movable part.

[0031] The system components 23-29 shown here are mounted on the load-bearing frame or foundation frame 22.

[0032] In the illustrated embodiment, as a conveying mechanism, the driving motion originates from a toothed belt drive driven by an electric motor, which causes a guided drive slide 26 with a pivotable drive element 29 fixed thereto to move reversibly between two positions, wherein the travel areas of the two sections of the conveying system intersect. More precisely, the drive unit 28 is implemented by means of two electric motors mechanically synchronized with each other, thereby combining two parallel-running toothed belts as the conveying mechanism 27 to obtain advantageous redundancy in the drive system. If there is no requirement for a redundant drive system, a solution with only one toothed belt and drive can be used. The drive system can also be designed with alternative conveying mechanisms that use drive elements such as chains, lead screws, or rack and pinion drives, or also use linear motor technology or fluid-based actuators. Since the toothed belt drive requires very little maintenance, this drive element was chosen for the embodiment according to the invention shown here.

[0033] In the travel area of ​​the two sections of the conveying section of the conveying system, and further in the area where the conveying mechanisms intersect, the component carrier 21 is transferred to the next conveying unit and the conveying mechanism there, i.e., to the next section of the conveying system. The transfer position defined there is simultaneously a stationary processing position. In the illustrated variant, two outer toothed belts are fixed to a first driven drive slide, and two inner toothed belts are fixed to a subsequent driven drive slide, so that the toothed belts can be manipulated independently of each other. The asymmetrical structure of the toothed belt drive also makes it feasible for the drive slides to travel in a staggered manner.

[0034] The linking principle of the section or conveying mechanism continues along the entire length of the conveying section.

[0035] Figure 3 The stationary manipulation and locking unit 23, referred to simply as locking unit 23, is shown as the central element.

[0036] Since the component carrier 1 has a form-fitting relationship with the connecting mechanism 29 (hereinafter also referred to as the drive member) or the stationary operating and locking unit 23 throughout the entire time, component processing can begin directly after the transport motion ends. The return stroke of the unlocked drive slide 26 is thus achieved during the processing. If the drive slide 26 is back in its starting position, the pivotable drive member 29 fixed thereon can pivot into the next connecting mechanism (drive bolt) at the component carrier 21 by means of the locking unit 3. Therefore, the pivotable drive member 29 can take a locked or unlocked posture toward the component carrier 21.

[0037] Figure 5 A front view of an embodiment of the invention in a static locked state is shown, wherein the actuating and locking unit 23 surrounds the driving bolt 20, i.e., the connecting mechanism, in a shape-matched manner.

[0038] Alternatively, a drive component modification is possible, wherein the torque load generated by the distance from the toothed belt 27 to the drive bolt 20 is absorbed by the component carrier 21 rather than by the drive slide 26.

[0039] Similarly, replacing the reciprocating drive mechanism here can also achieve one or more cyclic drives, but this means a more complex drive system design and a negative impact on structural space. If only a very small amount of structural space is available transversely to the transport direction, a reversible drive principle based on horizontal telescopic forks would be considered; however, this is also associated with higher manufacturing costs.

[0040] Furthermore, the movable drive units 26 and 29 can be designed so that no external medium supply is required.

[0041] The position detection of the guided and driven slide 26 is indirectly performed via an angle measurement system at the electric motor drive unit 28. This is because, in a traction-operated and thus flexible drive system, direct length measurement of the travel path negatively impacts the adjustability and vibration characteristics of the drive, and consequently, the positioning accuracy of the component carrier. Furthermore, the tension of the toothed belt due to acceleration or deceleration forces must be considered. Since high repeatability is required during deceleration, the synchronous pulley at the rear of the toothed belt drive in the conveying direction should be driven. This advantageously allows for the loading of a shorter section of the toothed belt drive during deceleration.

[0042] As a safety device, a redundant drive system in the illustrated variant is proposed, featuring a dual-motor implementation. Alternatively, at least at the end of the conveying section (section), a manipulated overrun protection device with feedable damping technology is considered.

[0043] The previously described synchronization problem of drives between processing stations is avoided by using undriven load-bearing rollers.

[0044] If, for example, additional lifting of the component carrier is required for better accessibility to the production process, the component carrier can be transported directly on the load-bearing drive slide 26, thus eliminating the need for the load-bearing rollers 24.

[0045] To buffer the high energy demands during acceleration and deceleration phases, the transport section should be equipped with energy storage devices. These devices could be based on capacitors or secondary battery technology (storage batteries), which would significantly reduce the load on the energy supply network. Mechanically operated energy storage devices in the form of flywheel energy storage units are also considered, but these are structurally costly.

[0046] A key aspect of the solution presented is the creation of a shape-fitting horizontal conveying system capable of reliably and repeatedly achieving highly dynamic positioning tasks with large masses and consequently high acceleration and deceleration forces within a very short cycle time. Specifically, the conveying motion is performed via electric motor-driven, station-associated actuators 26 and 29, which are shape-fitted to the component carrier, and their positions are detected directly or indirectly using a displacement measurement system.

[0047] Therefore, it can eliminate the cost of external displacement measurement technology at the component carrier, which is susceptible to vibration and interference.

[0048] Inside the processing station, the component carrier is transferred indirectly or directly to the drive unit of the next station by means of a feed motion, wherein the component carrier is kept mechanically guided throughout the entire area of ​​the conveying facility according to the invention, i.e., continuously and form-fittingly connected to the conveying mechanism or fixed component.

[0049] Further advantages are derived from the design of the component carrier, which can be equipped with drive elements of a simple and robust design, a significant economic advantage given the large number of component carriers in manufacturing facilities and, consequently, in conveyor systems. Similarly, component carriers can be transported in areas of the return route or in assembly line operation, in a manner that is not necessarily form-fitting in conventional conveying technologies. The subject matter of the invention allows for both low-cost manufacturing and low-maintenance operation of the entire conveyor system, and can be implemented with the aid of redundant structures, ensuring high reliability and thus facility availability. Combined with a suitable energy storage device capable of buffering high energy demands or flows during acceleration and deceleration phases of the conveying process, the invention forms the basis for reliable and energy-efficient high-performance conveyor facilities for cyclic mass production.

Claims

1. A conveying system for industrial manufacturing facilities, The conveying system has a conveying section equipped with a stationary-driven linear conveying mechanism (27), specifically including at least one toothed belt or chain extending in the conveying direction. in, The component carrier (21) can move along the conveying section by means of the conveying mechanism (27). The component carrier (21) can be connected to the conveying mechanism (27) in a form-fitting manner and can be decoupled from the conveying mechanism (27). At least one stationary locking unit (23) is provided on the conveying section, and The locking unit (23) is designed to decouple the component carrier from the conveying mechanism (27) and to fix the component carrier (21) in a fixed position during a single working stroke. Its features are, The conveying section of the conveying system consists of multiple interconnected sections. Each section is equipped with the linear conveying mechanism or another stationary driven linear conveying mechanism (27). The stationary locking unit (23) is arranged at the connection point of the two sections, allowing the component carrier (21) to be selectively connected to or decoupled from the first or second section of the two sections of the conveying mechanism (27), wherein the component carrier (21) is transported between the sections. Wherein, the segments overlap each other in the transfer area, and Among them, a fixation is provided between the component carrier (21) and the shape-matching connection between the shape carrier (27) of the first section and the second section and the component carrier (21).

2. The conveying system according to claim 1, Its features Suppose that, during the transfer process, both the decoupled and coupled conveying mechanisms are stopped.

3. The conveying system according to any one of the preceding claims, Its features are, The locking unit (23) is designed to couple the component carrier (21) to the conveying mechanism (27) and to release the component carrier (21) from a fixed position during a single work trip.

4. The conveying system according to any one of the preceding claims, Its features are, The locking unit (23) is designed to provide uninterrupted guidance of the shape fit of the component carrier (21) during decoupling and fixing and / or during coupling and release of the component carrier (21).

5. The conveying system according to any one of the preceding claims, Its features are, In order to fix the component carrier (21), the component carrier (21) can be connected to the locking unit (23) or to the stationary component of the conveying section, especially to the shape of the bearing frame or base frame (22) of the conveying section.

6. The conveying system according to any one of the preceding claims, Its features are, The locking unit (23) has movable components, particularly sliders arranged transversely to the direction of travel of the component carrier (21), wherein the components are designed to be coupled or decoupled from the connection mechanism (20) of the component carrier (21), particularly pin coupling, and wherein the components are designed to decouple or couple the drive of the conveying mechanism (27) from the connection mechanism or other connection mechanism (20) of the component carrier (21) during the same movement.

7. The conveying system according to any one of the preceding claims, Its features are, The locking unit (23) has a capture area relative to the longitudinal direction of the conveyor, wherein the capture area is designed to compensate for the positioning tolerance of the component carrier (21) when the component carrier (21) is fixed, and / or to compensate for the positioning tolerance of the conveying mechanism (27) when the component carrier (21) is coupled to the conveying mechanism (27).

8. The conveying system according to any one of the preceding claims, Its features are, The conveying system has an energy storage device, wherein the energy storage device is designed to store at least partially the kinetic energy of the component carrier (21) and / or other movable parts of the conveying system, particularly the conveying mechanism (27), during deceleration before engagement with the locking unit (23), and wherein the energy storage device is designed to release the stored energy after the component carrier (21) is coupled to the conveying mechanism or other conveying mechanism (27), and In order to control the timing of energy release, a sensor is provided on the locking unit (23) to detect the coupling state of the locking unit (23).

9. The conveying system according to any one of the preceding claims, Its features are, The conveying system has a variable propulsion of the conveying mechanism (27), wherein the variable propulsion is controlled such that the conveying mechanism (27) stops at the time when the component carrier (21) is connected to the locking unit (23) and at the time when the component carrier (21) is coupled to the conveying mechanism (27).

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