DE102016203814B4 - Device for transporting packaging materials, in particular bottles or cups - Google Patents

Abstract

Device for transporting packaging materials, in particular bottles or cups, comprising
- at least one transport device (10),
- at least one drive (16, 18) for the transport device (10),
- at least one workstation (20, 22, 24, 26, 28),
- at least one packaging carrier (14) for transporting packaging material, which the transport device (10) moves along at least one work station (20, 22, 24, 26, 28),
where
- at least one sensor (30, 32, 35) is provided for monitoring the packaging carrier (14),
characterized by the fact that
- an evaluation unit, preferably a control unit (34), is provided which determines an elongation of the chain (12) by interpolation at at least one workstation (20, 22, 24, 26, 28) depending on the distance (38, 40) of two packaging carriers (14).

Description

State of the art

The present invention relates to a device for transporting packaging materials, in particular bottles or cups, according to the preamble of the independent claim.

A generic device for transporting bottles or the like is, for example, made from the DE 195 42 673 C2 known. The conveyor system has an endless chain, with at least one stationary measuring device for the length of the chain arranged on the orbit of the chain.

Furthermore, it is from DE 10 2012 004 372 A1 , DE 102 49 962 A1 and DE 10 2011 103 152 A1 A device for transporting packaging materials, comprising at least one transport device and at least one drive for the transport device, is known. EP 2 706 026 A1 , DE 10 2010 043 057 A1 and DE 10 2015 225 834 A1 A transport device is known.

The invention is based on the objective of further increasing the accuracy of the transport device. This objective is achieved by the features of the independent claim.

Disclosure of the invention

In contrast, the device according to the invention for transporting packaging materials according to the features of claim 1 has the advantage that the wear and elongation of the chain or the transport system, which would lead to reduced chain tension, are detected and mitigated. This enables precise positioning of the packaging material carriers relative to the processing stations. Mispositions that could lead to collisions with other stations are avoided. Furthermore, the movement quality of the packaging material carriers is improved by reducing shocks and vibrations that would otherwise cause significant wear and tear. Manual readjustment between the modules and the chain is unnecessary, as this can be done automatically with the device according to the invention.

According to the invention, this is made possible by providing at least one sensor for monitoring the packaging carrier. Monitoring the position of the packaging carrier is particularly advantageous for its precise positioning relative to a workstation. Furthermore, the position can be easily detected. This sensor makes it especially easy to determine wear on the transport device, particularly on a chain as a component of the transport device. The condition of the transport device can be monitored either intermittently or continuously using this sensor, and targeted countermeasures can be taken by appropriately controlling a drive for the transport device and/or the workstations. For this purpose, preferably at least one controller is provided that controls the drive based on at least one output signal from the sensor.

In a suitable further development, the sensor is arranged so that it can detect the distance between two packaging carriers. The distance, which represents a measure of chain elongation, can be detected in a particularly simple manner.

In a suitable further development, it is planned that the control system will activate at least one workstation depending on the sensor's output signal. Since the detected state of the transport system affects the relative positioning of the packaging carrier to the workstation, misalignments can be compensated for particularly easily. This increases the safety of the setup.

In a practical refinement, the sensor is positioned laterally to a chain of the transport device in such a way that it can detect the distance between two packaging carriers. The distance between two packaging carriers provides information about the extent to which the chain has already elongated. Furthermore, this measurement can be used to more precisely position the packaging carrier relative to the workstation.

In a suitable further development, an evaluation unit, preferably a control unit, is provided that generates a warning signal when a certain distance between two packaging carriers is exceeded. This allows for a particularly simple indication of impermissible chain elongation and the need for its replacement or other countermeasures such as retensioning, etc.

In a practical further development, the sensor is arranged to detect the distance between the packaging carrier and a receptacle, the receptacle connecting the packaging carrier to the transport device, in particular the chain. This allows the existing sensor to be used for further monitoring of the proper attachment of the packaging carrier. They can be used on the chain or attachment. This increases the safety of the setup.

In a preferred embodiment, the sensor is arranged laterally to the chain with a detection direction perpendicular to the transport direction of the conveying device. This makes it particularly easy to detect the distance between two packaging carriers. Particularly preferred is the sensor arranged with a detection direction perpendicular to the transport direction of the conveying device, preferably above or below the chain. This is especially space-saving.

In a suitable further development, an evaluation unit, preferably a control unit, is provided that determines the total elongation of the chain depending on the distance between two packaging carriers. This allows the last workstation, especially a packer, to be positioned precisely so that any gripping operations can be carried out accurately and without damaging the packaging material.

According to the invention, an evaluation unit, preferably a controller, is provided which determines the elongation of the chain by interpolation at at least one workstation, depending on the distance between two packaging carriers. This allows the respective positional offset of the packaging carrier relative to the respective workstation to be determined and corrected if necessary.

Preferably, the workstations are a transfer station and/or a sealing station and/or a filling station and/or a packaging station and/or a testing station and/or a packer.

In a suitable further development, at least one additional drive is provided for powering the transport device, with at least one of the two drives being controlled to adjust the desired tension of the transport device, in particular a chain and/or belt of the transport device, for the further transport of the packaging carrier. Especially in combination with the sensor that detects chain elongation, the appropriate control of the drives can compensate for this elongation, particularly by adjusting the desired chain tension. This increases the positioning accuracy of the workstations relative to the packaging carriers, which contributes to eliminating susceptibility to malfunctions and thus to the safety of the device.

Further appropriate training courses result from other dependent requirements and the description.

Brief description of the drawing

• 1 eine perspektivische Ansicht der Transportvorrichtung beim Durchlaufen verschiedener Arbeitsstationen,
• 2 eine vergrößerte Darstellung der Anordnung des Sensors am Ende der Transportvorrichtung,
• 3 eine vergrößerte Darstellung der Anordnung des Sensors zu Beginn der Transportvorrichtung,
• 4 eine perspektivische Ansicht der Transportvorrichtung mit drei Sensoren sowie
• 5 eine perspektivische Ansicht der Transportvorrichtung mit einer alternativen Anordnung von zwei Sensoren.

Preferred embodiments of the invention are described in detail below with reference to the accompanying drawing. The drawing shows:

• 1 a perspective view of the transport device as it passes through various workstations,
• 2 an enlarged view of the sensor arrangement at the end of the transport device,
• 3 an enlarged view of the sensor arrangement at the beginning of the transport device,
• 4 a perspective view of the transport device with three sensors as well as
• 5 a perspective view of the transport device with an alternative arrangement of two sensors.

Description of the exemplary embodiment

The following refers to the 1 , 2 , 3 , 4 until 5 A transport device 10 is described in detail. The transport device 10 is used for transporting packaging materials such as cups or bottles, particularly in filling plants for liquid or pasty food products. However, its use is not limited to this. The transport device 10 comprises at least one chain 12 or a belt. A plurality of carriers 13 are attached to the chain 12. These carriers 13 interact with packaging carriers 14 that are attached to them. The packaging carriers 14 have receptacles 15 in the form of circular recesses for receiving a packaging material (not shown). Several receptacles 15 can be provided per packaging carrier 14, so that several packaging materials can be transported and processed simultaneously, for example, filled and sealed. Each of the two end faces of a packaging carrier 14 is connected to a chain 12. The packaging carriers 14 are moved along different stations 24, 26 or workstations via the chains 12.

The chain 12 is driven via at least one drive wheel 17, which is moved by a drive 16. A deflection 19 is provided on the other side of the transport device 10. The deflection 19 is also driven by another drive 18. Here, for example, teeth (not shown) engage with the chain 12.

A sensor 30 is arranged on the transport device 10, preferably at the beginning of the transport device 10. The sensor 30 is located, for example, in the area of the transfer station 20. As will be shown in more detail later, the sensor 30 is arranged outside the chain 12 so that any elongation of the chain 12 can be reliably detected. Optionally, a further sensor 32 can be provided. This could, for example, be arranged at the other end of the transport device 10, as shown in the exemplary embodiment. In the exemplary embodiment, the further sensor 32 is located in the area of the packer 28. However, it is also possible to arrange only a single sensor 30 on the transport device 10. Alternatively, only the further sensor 32 could be provided in the area of the packer 28.

Sensor 30 sends a sensor signal 31 to a controller 34. The other sensor 32 sends another sensor signal 33 to the controller 34. The controller 34 may be used to control the drive 16 and/or the other drive 18. The controller 34 may also receive corresponding position signals from the drives 16 and 18, or other parameters of the drives 16 and 18, such as the applied torque, speed, or similar information. An operator interface 36 is connected to the controller 34. The user can send corresponding operating commands to the controller 34 via this interface 36. Furthermore, relevant information or warning messages can be output to the operator via the interface 36. The controller 34 can optionally be connected to the transfer station 20 and/or the further stations 24, 26 and/or the reference station 22 and/or the packer 28 as examples of possible workstations for controlling and/or providing feedback of relevant parameters. The term controller 34 is by no means to be interpreted restrictively, but encompasses the control systems typical for servo drives with associated control loops, for example, regarding position, speed, torque, or similar parameters.

A transfer station 20 is provided at the beginning of the transport device 10. The packaging material can be fed to the respective packaging carrier 14 via this transfer station 20. The transfer station 20 is slidable along a transport direction 9 of the transport device 10 or the chain 12, preferably in a horizontal direction. The transfer station 20 extends over the entire packaging carrier 14, so that each of the receptacles 15 can be filled with packaging material.

A reference station 22 is arranged transversely to the transport direction 9 of the transport device 10, spanning the entire width of the transport device 10. The reference station 22 could, for example, be located in the center of the transport device 10. The reference station 22 is a specific workstation whose position serves as the reference position for the drives 16, 18. Particularly when using servomotor drives 16, 18, automatic referencing to the freely chosen zero point in the machine is possible.

Further stations 24 and 26 are connected; two workstations are shown as examples, but there can be fewer or more. These further stations 24 and 26, or even just individual workstations, can also be moved in the transport direction 9 of the transport device 10. This adjustability of stations 24 and 26, or workstations, can be used to adjust the positioning of stations 24 and 26 to any detected changes in the length of the chain 12. Possible stations 24 and 26, or workstations, include, for example, a sterilization module, a filling device, a sealing device for applying a lid film, or similar components to a filled package. Stations 24 and 26 can also be used for extracting foreign particles, applying snap-on lids, control systems (e.g., for cup tightness), or labeling systems for marking or coding a lid, or similar functions. The packaging carriers 14 serve to transport the packaging material to the workstations 20, 22, 24, 26, 28 required depending on the work steps.

As its final station, the transport device 10 approaches a packer 28. This packer 28 can pick up appropriately processed packaging materials (e.g., filled and sealed cups) and feed them into further processing steps. When the transport device 10 is integrated as part of a filling machine with a downstream packaging system, in which the packer 28 is used, the gripper system of the packer 28 is subject to increased demands. The packer 28 collects individual packages in a tray to form a multi-pack. Even slight deviations in positioning can lead to malfunctions in the packer 28 or damage to the packaging material. The sensor signal 33, which measures the positional deviation of two adjacent packaging carriers 14—namely, the determined distance 40 relative to a target dimension—can be transmitted to the packer 28. The packer 28 can then precisely control the picking movement of a gripper to the center of the packaging carrier 14. This is preferably done depending on the determined distance 40 or a deviation from the target. Alternatively, sensor signals 33, 37 from further sensors 32, 35 could also be used. In this case, the elongations of the chain 12 determined by further sensors 32, 35 can be extrapolated to the position of the packer 28. It is assumed that the chain 12 has elongated uniformly. Based on the known distance between the respective sensor 32, 35 and the packer 28 or the other desired workstation 20, 22, 24, 26, the resulting elongation is extrapolated or interpolated. Using this determined elongation, the corresponding workstations 20, 22, 24, 26, 28 can be moved further in the transport direction 9.

An excerpt from the 1 is now in 2 The sensor 32 is shown enlarged. It is positioned laterally to the chain 12 such that, in a specific position, it determines the distance 38 between two adjacent packaging carriers 14 along the transport direction 9. The sensor 32 is located at the end of the transport device 10 near the packer 28. The elongation of the chain 12 is determined based on the distance 38 between two adjacent packaging carriers 14. For this purpose, the sensor 32 is oriented with its detection range transversely to the transport direction 9 of the transport device 10. The detection range is preferably selected such that the distance 38 between two packaging carriers 14 can be reliably detected, both in the normal state and in the state of an elongated chain 12. The corresponding sensor signal 33 is sent to the control unit 34 for further evaluation. Sensor 32 thus serves to measure the offset of the chain links or packaging carriers 14 in the transport direction of the transport device 10. Sensor 30, 32 detects the current elongation of the chain 12 based on the determined distances 38, 40.

In the enlarged view according to 3 Sensor 30 is located in the area of the transfer station 20. Similar to sensor 32 at the packer 28, sensor 30 is oriented so that a distance 40 between two adjacent packaging carriers 40 can be reliably detected in the area of the transfer station 20. A corresponding sensor signal 31 is forwarded to the controller 34. The other sensor 32 is stationary and located laterally to the moving chain 12. Its detection range is oriented so that it reliably detects the end faces of the packaging carriers 14 and their distance 40. Alternatively, sensor 30, 32 could also be oriented so that it also detects the area between the carrier 13 and the packaging carrier 14, i.e., a distance perpendicular to the transport direction 9. This allows monitoring of the correct attachment of the packaging carrier 14 to the carrier 13. If the distance between the carrier 13 and the end face of the packaging carrier 14 is too large, perpendicular to the transport direction 9, a faulty fastening is assumed. This can be signaled to the user with a corresponding message at interface 36.

The order according to 4 differs from that of the 1 The design includes an additional sensor 35, resulting in a total of three sensors 30, 32, and 35. This (third) sensor 35 is also located laterally to the chain 12 in the area of reference station 22. The first sensor 30 is located at the beginning of the transport device 10 in the area of transfer station 20. The (second) sensor 32 is located at the end of the machine or transport device 10 on the packer 28. This measures the total elongation of the chain 12 from station 20, through station 22, to station 28. The additional sensor 35 sends another sensor signal 37 to the controller 34.

The order according to 5 differs from that of the 4 The difference lies in the fact that sensor 32 is now missing in the area of packer 28. Therefore, only two sensors are provided: sensor 35 in the area of reference station 22 and sensor 30 in the area of transfer station 20, each arranged laterally to the chain 12. The chain elongation at the end of the machine or transport device 10 at packer 28 is scaled linearly up over the distance from station 20 to station 22, and possibly to further workstations, such as packer 28.

The drive wheel 17, which serves to propel the chain 12, is driven by the drive 16, preferably a servo motor, particularly with a gearbox. The deflection wheel or deflection 19 is also moved by a further drive 18, which likewise acts to propel the chain 12. This further drive 18 can also preferably be a servo motor, particularly with a gearbox. The drives 16, 18 operate in a mode in which the chain 12 is tensioned without play in an upper chain run during movement and standstill and is subjected to the lowest possible preload defined by the drives 16, 18. For this purpose, at least one of the two drives 16, 18 is controlled to set a desired tension of the transport device 10, in particular of the chain 12 and/or a belt of the transport device 10. In this context, tension is understood in particular to mean a mechanical load exerted on the transport device 10, in particular on the chain 12. For this purpose, the drives 16, 18 are moved into positions in which the chain 12 is preferably tensioned without play. With the desired backlash-free tension of the chain 12, the position of the drives 16, 18 depends over time on the increasing elongation of the chain. Chain 12 is disengaged. Thus, at least one of the drives 16, 18, taking into account any elongation of the chain 12, is moved to a position relative to the other drive 16, 18 in which this elongation is compensated. This could, for example, correspond to the increase in elongation. Alternatively, at least one of the drives 16, 18 could, for example, be actuated and moved while the other drive 16, 18, which exerts a holding torque on the chain 12, is stationary, until a significant increase in torque would be necessary to achieve the next position increment. This increase in torque indicates that the chain 12 is now sufficiently tensioned.

The drives 16,18 can then be controlled for normal transport of the packaging carrier 14, for example synchronously with speed, as described below, so that the desired tension of the chain 12, for example in the form of the desired length of the chain 12, which lies between the two drive wheels 17,19, is maintained.

Thanks to the preferably servo-motor-driven drives 16, 18, automatic referencing to a freely selectable zero point in the machine is possible. The drives 16, 18 can be set in a freely selectable ratio to distribute the pulling and pushing loads. For example, the pulling load is assigned a ratio of 50–90% of the total load, and the pushing load a ratio of 10–50% of the total load. The design of the drives 16, 18, including the size-determining drive 16, 18, can typically be one standard size smaller than with individual drives. The maximum load of the chain 12 of the packaging carrier 14 is higher than with individual drives.

The drives 16 and 18 preferably operate in a master-slave configuration with a tensioning function between drive 16 and drive 18. This ensures that the chain 12 is kept constant and smooth, without backlash. The drive system is referenced to a defined zero point. During production, the system can be held at the center of the station (the respective station 24 or 26). Alternative reference points can be defined in the transport chain 12, which can be activated as needed.

The pulling drive 16, 18 is the master, the pushing drive 18, 16 the slave. In the exemplary embodiment, with the transport direction 9 shown, drive 18 would be the pulling drive, i.e., the master, and drive 16 at the beginning of the transport device 10 would be the slave. There are different ways to operate the drives 16, 18. In a first variant, the control technology is simpler. Here, the slave drive 18, 16 follows the master drive 16, 18 synchronously. For this purpose, the controller 34 sends corresponding setpoint speed values to the two drives 16, 18.

In another variant, both drives 16, 18 follow the motion profile of a virtual axis. The slave drive 18, 16 operates with a position offset (input, e.g., 2 mm). The position offset causes a slight lag, resulting in tension on the chain 12. As the chain 12 gradually stretches during operation, the drive torque of the slave drive 18, 16 decreases. The controller 34 of the slave drive 18, 16 detects this decreasing torque. The controller 34 increases the offset value to maintain a constant torque of the slave drive 18, 16 and thus a constant tension on the chain 12.

The return of the chain 12 or the upper run, which is not explicitly shown in the figures, can be tension-free. There are different variations. For example, the chain 12 can be laid down during the return run. Alternatively, a chain 12 with tensioning wheels could be provided during the return run. Furthermore, a drive wheel 17 or a deflection 19 with a tensioning function in the transport direction 9 would be possible.

The machine length, or the length of the transport device 10, is known. Therefore, the target dimension (theoretical dimension) of the machine or transport device 10 from station 20 to station 28 is known. The machine and the modules or stations 20, 22, 24, 26, 28 mounted on it have a displacement range of approximately half the width of the packaging carrier 14 (e.g., 50 mm). When the chain stretches by approximately 0.5%, the limit of the adjustment range of a module or station 20, 22, 24, 26, 28 is reached. After this, a chain 12 must be replaced with a new one. Using sensors 30, 32, and 35 for measuring chain elongation and machine operating times, predictions for maintenance and adjustment of the machine are possible, for example, a prediction of the time until the next readjustment of modules or stations 20, 22, 24, 26, and 28, or the time for a chain change. This information is output via interface 36. The actual position of chain 12 can be calculated for each machine station (stations 20, 22, 24, 26, and 28). The offset between the actual value and the target value yields the current difference. The controller 34 and interface 36 inform the operator whether the machine is operating within a safe operating range or whether the workstation (stations 20, 22, 24, 26, and 28) or the module needs readjustment. Readjustments can be performed fully automatically or manually. For this purpose, the controller 34 could send corresponding signals to the (Work) stations 20, 22, 24, 26, 28 are given in order to, for example, slightly change the position according to the current lengthening of chain 12.

The sensor 30, 32, 35 for the positioning accuracy of the packaging carrier 14 or the chain 12 can receive a signal in the vertical direction in addition to a signal in the transport direction 9 (chain elongation measurement function). Packaging carrier 14 that has become detached from the carrier 13 of the chain 12 (for example, due to loosened screw connections) is thus detected when the distance between the packaging carrier 14 and the carrier 13 exceeds a permissible dimension. The interface 36 alerts the operator to the need for troubleshooting. The packaging carrier 14 can be automatically moved to a repair position.

Alternatively, the sensor(s) 30, 32, 35 could be arranged above or below the packaging carriers 14, preferably laterally, to detect the gap between two adjacent packaging carriers 14 from above or below. Alternatively, a bore or countersink in the packaging carrier 14 or a pin on the packaging carrier 14 could also be detected. Detecting a roller of the chain 12 during a measurement from below also provides information about the condition of the chain 12. Thus, the sensor 30, 32, 35, which is equipped with a certain level of intelligence, can directly output a signal corresponding to an analog value of the chain elongation. Furthermore, the sensor 30, 32, 35 could directly output an alarm signal if the chain 12 is worn. This would occur if the current chain elongation exceeds a permissible limit.

In filling machines where the transport device 10 is preferably used, workstations such as stations 20, 22, 24, 26, and 28 with high positioning accuracy are particularly important. These include, for example, stations 24 and 26 for the extraction of foreign particles, snap-on lids, cup leak testing, and lid marking or coding.

These machines, along with their associated transport devices, are primarily used in the dairy industry and for filling liquid to pasty foods, including baby and hospital food. Increasingly, these filling machines are also being used for soft drinks, soups, and sauces.

Claims (14)

Device for transporting packaging materials, in particular bottles or cups, comprising: - at least one transport device (10), - at least one drive (16, 18) for the transport device (10), - at least one work station (20, 22, 24, 26, 28), - at least one packaging carrier (14) for transporting packaging materials, which the transport device (10) moves along at least one work station (20, 22, 24, 26, 28), wherein - at least one sensor (30, 32, 35) is provided for monitoring the packaging carrier (14), characterized in that - an evaluation unit, preferably a control unit (34), is provided which determines an elongation of the chain (12) by interpolation at at least one work station (20, 22, 24, 26, 28) depending on the distance (38, 40) between two packaging carriers (14). Device according to Claim 1 , characterized in that the sensor (32, 32, 35) is arranged such that the sensor (30, 32, 35) can detect a distance between two packaging carriers (14). Device according to one of the preceding claims, characterized in that the sensor (30, 32, 35) is provided for detecting a dimension (38, 40) for detecting wear, in particular elongation of a chain (12) of the transport device (10). Device according to one of the preceding claims, characterized in that at least one control unit (34) is provided which, depending on at least one output signal (31, 33, 37) of at least the sensor (30, 32, 35), controls the drive (16, 18). Device according to one of the preceding claims, characterized in that at least one controller (34) is provided which controls at least one workstation (20, 22, 24, 26, 28) depending on the output signal (31, 33, 37) of the sensor (30, 32, 35). Device according to one of the preceding claims, characterized in that an evaluation unit, preferably a control unit (34), is provided which generates a warning signal when a distance (38, 40) between two packaging carriers (14) is exceeded. Device according to one of the preceding claims, characterized in that at least dest a control (34) is provided which positions at least one workstation (20, 22, 24, 26, 28) relative to the packaging carrier (14) depending on the output signal (31, 33, 37) of the sensor (30, 32, 35). Device according to one of the preceding claims, characterized in that the sensor (30, 32, 35) is arranged such that the sensor (30, 32, 35) determines a distance between the packaging carrier (14) and a receptacle (13), wherein the receptacle (13) connects the packaging carrier (14) with the transport device (10), in particular the chain (12). Device according to one of the preceding claims, characterized in that the sensor (30, 32, 35) is arranged laterally from the chain (12) with a detection direction transverse to the transport direction (9) of the transport device (10). Device according to one of the preceding claims, characterized in that the sensor (32, 30, 35) is arranged with a detection direction perpendicular to the transport direction (9) of the transport device (10), preferably above or below the chain (12). Device according to one of the preceding claims, characterized in that the sensor (30, 32, 35) is arranged adjacent to at least one work station (20, 22, 24, 26, 28), preferably at the beginning and/or in the middle and/or at the end of the transport device (10). Device according to one of the preceding claims, characterized in that an evaluation unit, preferably a control unit (34), is provided which determines a total elongation of the chain (12) depending on the distance (38, 40) of two packaging carriers (14). Device according to one of the preceding claims, characterized in that at least one further drive (16, 18) is provided for driving the transport device (10), wherein at least one of the two drives (16, 18) is controlled to adjust a desired tension of the transport device (10), in particular a chain (12) and/or a belt of the transport device (10), for the further transport of the packaging carrier (14). Device according to one of the preceding claims, characterized in that the work station (20, 22, 24, 26, 28) is at least a transfer station and/or a sealing station and/or a filling station and/or a packaging station and/or a testing station and/or a packer.