Method for monitoring folding tools

Abstract

The invention relates to a method for monitoring folding tools (8, 9) for a capper (1000) for closing a container (100), wherein the method comprises the following: providing a folding tool (8, 9) and a monitoring device (20) for monitoring the folding tool (8, 9), wherein the monitoring device (20) comprises a rotation sensor (21, 22) connected to the monitoring device (20) by means of which the rotation of the folding tool (8, 9) can be measured; rotating the folding tool (8, 9) and monitoring the folding tool (8, 9) by measuring a time course of the rotation of the folding tool (8, 9) by means of the rotation sensor (21, 22).

Description

[0001] The invention relates to a method for monitoring the folding tools of a seamer. The invention further relates to a device and a seamer for carrying out the method according to the invention.

[0002] In the filling process for beverage or food cans, the cans, after being filled with the beverage or food, pass through a can sealer. The filled cans enter the machine via one feed path, and can lids enter via another. The can sealer typically has several identical, carousel-like arrangements, each of which seals a can with a lid. The lids are guided onto the cans and held in place by a crimping head. This holding action also prevents the cans from breaking out of their circular path within the sealer due to centrifugal force. Inside the sealer, the can and lid are crimped over a crimping roller, thus sealing the can. The crimping head usually also rotates the can and lid around its own axis of symmetry during this process.For rotation, the folding rollers and folding heads are arranged on a respective folding shaft or folding roller bolt.

[0003] A can sealer of this type is described in DE 749636 and DE 4234115 A1. The can sealer comprises a clamping device for holding a can to be sealed. In the operating state, the can to be sealed is placed in the clamping device and secured by it in the axial and radial directions. A can lid is also positioned centrally over the opening of the can to be sealed. The can has a circumferential can flange in the area of ​​the opening, and the can lid has a circumferential lid flange. To seal the opening with the lid, the can sealer additionally comprises two crimping rollers, each rotatably mounted about an axis, which press the can flange and the lid flange together by means of a substantially radial force. This pressing is achieved by continuous rolling in the circumferential direction along the circumference of the can opening.

[0004] Another can sealer is known from GB 2098899 A. This can sealer comprises a clamping device for holding the can to be sealed and a crimping roller. In operation, the can to be sealed is placed in the clamping device and secured axially and radially by it. A can lid is also positioned centrally over the opening of the can to be sealed. The can has a circumferential can flange in the area of ​​the opening of the can body, and the can lid has a circumferential can lid flange.

[0005] To seal the cans, folding tools are required, including the aforementioned folding rollers and folding heads. These tools deform the metal of the can and lid and are therefore subject to wear caused by pressure and friction. The folding tools must therefore be replaced periodically. An important quality indicator for folding rollers is the number of cans guaranteed by the manufacturer to be sealed with that roller.

[0006] If the data is recorded properly, the number of sealed cans from a folding roll can be roughly determined, and the wear of the folding tools can be roughly monitored. However, this requires manual record-keeping by the user.

[0007] Therefore, there is no reliable method to monitor the wear of folding tools.

[0008] The object of the invention is therefore to provide a method for monitoring folding tools, as well as a device and a sealer, which avoid the adverse effects known from the prior art. In particular, it should be possible to monitor the wear of folding tools of a sealer accurately and reliably. This object is achieved by a method according to the invention for monitoring folding tools of a sealer, as well as by a device and a sealer for carrying out the method according to the invention.

[0009] According to the invention, a method for monitoring folding tools for a sealing device for closing a container is proposed. The method according to the invention comprises providing a folding tool and providing a monitoring device for monitoring the folding tool. The monitoring device includes a rotation sensor connected to the monitoring device via a signal, by which the rotation of the folding tool can be measured. The folding tool is rotated, in particular about a folding axis, and monitored by measuring the rotation of the folding tool over time using the rotation sensor.

[0010] In accordance with the invention, the measured temporal profile of the rotation can be evaluated by the monitoring device. This evaluation can, in particular, include determining the wear state of the folding tool from the temporal profile of the rotation.

[0011] In the inventive method, several folding tools, which can be used in particular for attaching a lid to a container, can be provided and monitored. Furthermore, a capper can be provided, which includes the folding tool and the monitoring device to monitor the folding tools during operation of the capper. Alternatively, the folding tool and the monitoring device can also be part of a test station for checking folding tools, which in particular checks folding tools after their manufacture.

[0012] In a preferred embodiment, the rotation sensor can be attached to the folding tool, and in particular, arranged within the folding tool. For example, the rotation sensor can be arranged within the folding tool by being mounted on a cover of the folding tool or on the inside of a housing of the folding tool. Alternatively or additionally, the rotation sensor can be arranged relative to the folding tool in such a way that the rotation of the folding tool is measurable. In particular, more than one rotation sensor can be used to check a single folding tool in order to verify the sensor measurements.

[0013] In this embodiment of the invention, the rotation sensor can be a Hall sensor, i.e., a sensor that measures a voltage difference generated across an electrical conductor when a magnetic field is perpendicular to the direction of electric current. In this way, rotation can be detected, since the Hall sensor can detect an approaching or receding magnetic field during rotation.

[0014] While the rotation sensor can also be an optical sensor or gyrometer, a Hall sensor is particularly preferred. Advantageously, the monitoring device can include a magnet, especially a permanent magnet, which interacts with the Hall sensor to measure the rotation of the folding tool. The Hall sensor can particularly preferably be a 3D Hall sensor. The magnet (especially the magnets) is preferably attached to or integrated into the folding tool, and the Hall sensor is preferably attached to or within the housing of the sealer or device. This can be implemented, in particular, by providing the Hall sensor as part of a measuring head inside the sealer / device. The Hall sensor can comprise a semiconductor layer supplied with a constant current.A magnetic field component perpendicular to the direction of the constant current influences the current, and the Hall sensor provides a usable Hall voltage that can be tapped and used to record the rotation over time. The Hall sensor thus interacts with the magnet by being excited differently depending on the rotational movement of the folding tool.

[0015] Furthermore, the monitoring device can include an electrical circuit board for generating output signals. To shield against external interference, the Hall sensor can be positioned between metallic shielding elements. The metallic shielding element can simultaneously act as a flux concentrator for the magnetic field generated by a permanent magnet component. A change in the Hall sensor signal is caused by a change in the relative distance between the Hall sensor and the magnet resulting from the rotation of the folding tool.

[0016] The folding tool can be a folding device rotatable around a folding axis, such as a folding roller for folding a lid onto the container, or a folding head for holding and rotating the container with the lid.

[0017] Within the scope of the invention, the rotation sensor can measure the rotation of the folding tool around the folding axis, i.e., how often the folding tool rotates within a specific time. In particular, the rotation sensor can measure the rotation frequency of the folding tool. Changes in the rotation frequency of the folding tool can be monitored. The wear condition of the folding tool can be determined, in particular, from abrupt changes in the rotation frequency. A sudden, especially step-like, decrease in the rotation frequency can be an indication of wear on the folding tool. If such a change in the rotation frequency is detected by the monitoring device, a wear signal can be output, allowing the corresponding folding tool to be replaced.

[0018] In the inventive method, it is particularly preferred to measure the rotation of the folding tool after completion of a container closing process and / or the rotation of the folding tool when the folding tool (in particular the folding roller) is not engaged with the container, or after the folding tool has been engaged with the container. If a folding tool such as the folding roller is no longer in contact with the container after it has been closed, the folding roller continues to rotate for a certain period of time due to the kinetic energy transferred from the container to the folding roller. The folding roller thus coasts down. Sudden changes in the rotational frequency during this coasting down, such as the folding roller suddenly stopping, can indicate that the folding roller is worn. If the folding roller coasts down for too long, this can also be an indication of increasing wear.

[0019] Monitoring the folding tool can include comparing the measured rotational profile of the folding tool with a standard. This standard can be stored in the monitoring device and represent the rotational frequency profile of a new / unworn folding tool. In particular, the measured downtime (time until standstill) of the folding tool can be compared with the standard (i.e., the downtime of a new / unworn folding tool).

[0020] According to the invention, a device for carrying out the method according to the invention is further proposed. The device comprises the folding tool and a monitoring device for monitoring the folding tool, wherein the monitoring device includes the rotation sensor connected to the monitoring device via a signal, by which the rotation of the folding tool can be measured. In particular, the device can be the test station.

[0021] Furthermore, a sealing device for carrying out the method according to the invention is proposed, which comprises the folding tool for attaching a lid to a container and the monitoring device for controlling and monitoring the sealing device, wherein the monitoring device comprises the rotation sensor connected to the monitoring device by means of which the rotation of the folding tool can be measured.

[0022] The sealer can have an arrangement within its working area comprising a plurality of sealing stations encompassing the folding tool. The rotation sensor can be positioned on the folding tool and / or the sealer such that the folding tool can be monitored by measuring its rotation around the folding axis.

[0023] In this embodiment of the invention, the monitoring device can be part of a control system for the seamer. The inventive method makes it possible to assign the wear status of each folding tool within the control system. For this purpose, each folding tool is equipped with a sensor (i.e., a rotation sensor) that allows the rotation of the folding tool to be measured.

[0024] The folding element is preferably detachably arranged at one end of the folding shaft, meaning it can be attached to the folding shaft via a fastening mechanism and thus be replaceable (e.g., for tool changes). The folding shaft can be designed as a folding head shaft, and the folding element as the folding head for fixing the can lid to the can body. The folding axis is then the axis around which the folding head shaft or the folding head rotates during operation. Alternatively or additionally, the folding shaft can be designed as a folding roller shaft, and the folding element as the folding roller for folding the can lid to the can body. The folding axis is then (alternatively or additionally) the axis around which the folding roller shaft or the folding roller rotates during operation.

[0025] Each folding tool can have a rotation sensor at the same location on a stator (i.e., a static / immobile part of the folding tool during operation / when the container is being sealed). Since increased hygiene requirements must be met in the sealing machine's working area, the rotation sensor can be recessed in the upper part of the sealing machine and only extend into the working area when the folding tools are being monitored. The rotation sensor can therefore be positioned on the sealing machine in such a way that it can be inserted into the working area.

[0026] In accordance with the invention, a limit value for a specific rotation parameter can be stored in the monitoring device, and a wear signal can be output via the monitoring device once this limit value is reached for the folding tool. This wear signal can either inform the user and / or stop the closing mechanism, thus enabling timely replacement / inspection of the folding tools.

[0027] The sealing process can include positioning the container on a lifting station of the sealing station and folding the lid onto the container using the folding roller and folding head. Finally, the sealed container can be removed from the sealing machine's working area.

[0028] The sealing station can include a sealing head for closing the container with the lid. The sealing head can include the folding means for folding the lid onto the container. The folding means can be the folding roller and the folding head. Each sealing head can therefore include at least one folding roller (especially preferably two folding rollers) and a folding head. The sealing head can include a folding shaft or folding roller pin rotatable about a folding axis, with the folding means arranged at one end of the respective folding shaft / folding roller pin (the folding head and folding roller are thus rotatable about the respective folding shaft / folding roller pin).

[0029] In particular, two folding rollers can be arranged on one folding lever, one folding roller for a first folding operation and one folding roller for a second folding operation. However, the first and second folding rollers can also be arranged on separate folding levers. The closing device or arrangement according to the invention can further comprise the lifting station (or a plurality of lifting stations) for lifting the container. The lifting stations can be arranged opposite the closing heads.

[0030] The sealing device according to the invention is preferably designed as a can sealer. The container can be a can and the lid a can lid, which are folded together by the can sealer. The can sealer typically comprises several identical sealing stations (preferably sealing heads and lifting stations) arranged in a carousel, in each of which a can is sealed with a can lid.

[0031] In the operating state of the can seamer, the seaming rollers, with their respective seaming profiles, are brought into contact with a can lid flange and a can flange of the can. Rotation of the can then causes the seaming roller to rotate circumferentially, seaming the can flange against the can lid flange. For rotation of the can, it is preferably clamped between the seaming head and the lifting station, with the seaming head rotating around the seaming axis along with the seaming shaft.

[0032] Within the scope of the invention, the term "can" can be understood to mean a rotationally symmetrical container which is closed by means of the can sealer and the associated crimping roller. A can preferably comprise a metal, in particular aluminum or steel.

[0033] In principle, the capper can preferably comprise at least two types of folding rollers with preferably different folding profiles (whereby the corresponding capping head includes folding rollers of both types), so that cans can be capped according to a double-fold principle, in which the cans are generally capped in two stages. Each type of folding roller is responsible for one stage. The first type of folding roller creates a pre-fold (first folding operation), while the second type of folding roller completely caps the can / container (second folding operation).

[0034] When the can is clamped in the sealing station between the lifting station and the folding head, the first folding operation is performed with the first folding roller of the sealing station, but the second operation is preferably performed with the second folding roller of a different (adjacent) sealing station. Therefore, the folding rollers of two sealing stations can always be involved in sealing a can.

[0035] The invention will now be explained in more detail using exemplary embodiments and with reference to the drawings. Fig. 1 a top view of a can sealer; Fig. 2 a side view of a locking station; Fig. 3 a folding roll; Fig. 4 A comparison of rotation frequencies of folding rollers.

[0036] Fig. 1 shows a top view of a can sealer 1000 according to the invention.

[0037] The can sealer 1000 according to Fig. 1 comprises two lid supply devices 11 for supplying a lid 101 to a lid feeder 10, which transports the lids 101 to the can 100.

[0038] The lid feeder 10 includes a lid movement device 4, which is arranged to be movable such that the lid 101 can be moved towards the can 100 by the lid movement device 4. For this purpose, the lid movement device 4 is attached to a shaft and arranged to be rotatable by this shaft, so that the lid 101 can be moved by a rotation of the lid movement device 4.

[0039] Furthermore, the lid feeder 10 includes a lid guide 15A, 15B arranged on the lid movement device 4 for guiding the lid 101 to the can 100. For this purpose, the lid guide 15A, 15B has a first rail 15A and a second rail 15B running parallel to the first rail 15A, wherein the lid 101 is arranged between the rails 15A, 15B such that the lid 101 is guided by the movement of a lid driver 19 of the lid movement device 4 between the rails 15A, 15B in the direction of point Z, where the lid 101 is joined with the can 100 entering along A from a container feeder 12.

[0040] Furthermore, the can sealer 1000 includes a folding process / arrangement 14 with sealing stations in the form of folding stations for sealing the can 100 with the lid 101. The folding process 14 is arranged in a working chamber 2 of the can sealer 1000, which is surrounded by a housing 3.

[0041] The lid 101 is inserted along C through the lid supply device 11 into the working chamber 2 of the can sealer 1000 and guided by the lid guide 15A, 15B to the can 100.

[0042] However, before the lids are placed on the lid guide 15A, 15B, a destacking process takes place in which the lids 101 are individually separated from a stack.

[0043] The cans 100 with lids 101 are then fed to the folding process 14. During feeding to the folding process 14, the can 100 and the lid 101 are gassed by a gassing device 5, which is stationary at the lid feeder 10 and the container feeder 12. Afterwards, the can 100 with the lid 101 is clamped and sealed by the folding process 14. The sealed can is conveyed by a further rotor into a can outlet 18.

[0044] Fig. 2 Figure 1 shows a schematic representation of a sealing station 1 with the can 100 to be sealed and the can lid 101, in which a monitoring device 20 is connected with rotation sensors 21, 22.

[0045] The sealing station 1 comprises a can support with lifting station 23, a folding head 9, and a folding roller 8 rotatably mounted about a folding shaft, with a folding roller profile 111. The can lid 101 is centered above the opening of the can 100. The can 100 has a circumferential can flange in the area of ​​the can opening, and the can lid 101 has a circumferential can lid flange.

[0046] During the closing process, the crimping roller 8 is brought into contact with the can flange and the can lid flange via the crimping roller profile 111. The can flange and the can lid flange are then pressed together by means of a substantially radial force applied via the crimping roller 8. This pressing is achieved by the continuous rolling of the crimping roller 8 in the circumferential direction along the circumference of the can opening.

[0047] For folding, the can 100 is rotated by a clamping device consisting of lifting station 23 and folding head 9, by rotating the folding head 9 with the folding shaft around the folding axis X.

[0048] The monitoring device 20 can be used to monitor the folding roller 8 and / or the folding head 9.

[0049] For this purpose, the folding roller 8 comprises a first permanent magnet 6 and the folding head 9 a second permanent magnet 7. In addition, the rotation sensors 21, 22, which are connected to the monitoring device 20, are arranged on the folding roller 8 and the folding head 9 respectively in such a way that the permanent magnets 6, 7 can act on the rotation sensors 21, 22, i.e., the permanent magnet 6 on the rotation sensor 21 and the permanent magnet 7 on the rotation sensor 22.

[0050] The rotation sensors 21 and 22 are Hall effect sensors. To monitor the folding roller 8 and the folding head 9, the folding head 9 is rotated together with the can 100 and the lifting station 23. Since the folding roller 8 moves circumferentially along the circumference of the can opening, it is also set into rotation. After the closing process of the can 100 is complete, i.e., when the folding roller 8 and the folding head 9 are no longer engaged with the can 100 and the lid 101, the rotation profile or rotation frequency of the folding roller 8 and the folding head 9 is recorded by the rotation sensors 21 and 22. The winding of the folding roller 8 is of particular interest here. Of course, it is also possible to monitor only the folding roller 8 or only the folding head 9.

[0051] To monitor the folding roller 8 and the folding head 9, the Hall sensors 21, 22 are supplied with a constant current by the monitoring device 21. The permanent magnets 6, 7 exert a magnetic field component perpendicular to the current direction on the constant current, and the Hall sensor provides a measurable Hall voltage, which is tapped by the monitoring device 20 and used to detect the rotational frequency. The folding roller 8 and folding head 9 can each comprise a plurality of permanent magnets.

[0052] If a sudden change in the rotation frequency, such as a sudden stop of the folding roller 8 as it is winding down, is detected, this is recognized by the monitoring device 20. The monitoring device 20 can then indicate, by means of an output signal, that the corresponding folding roller 8 is worn and needs to be replaced or inspected.

[0053] Furthermore, a standard for the temporal profile of the rotation of folding roller 8 and / or folding head 9 can be stored in the monitoring device 20. The measured profile of the rotation frequency is then compared with the standard by the monitoring device. This allows not only the detection of sudden changes as deviations from the standard, but also a comparison of downtimes. If a folding roller 8 runs for an excessively long time, this can indicate wear, in particular bearing wear.

[0054] Monitoring of the folding roller 8 and / or the folding head 9 can be performed either after each can 100 is sealed or at regular intervals, for example after 1000, 10000 or 100000 cans. The desired monitoring interval can be stored in the monitoring device 20 and, in particular, reduced as the number of sealed cans increases.

[0055] Fig. 3 Figure 1 shows a preferred embodiment of a folding roller 8 for the method according to the invention. The folding roller 8 comprises four permanent magnets 6 (in principle, any number of permanent magnets 6, such as 2 or 3, can also be used). The permanent magnets 6 are arranged on a folding roller cover 60 of the folding roller 8, which covers a bearing of the folding roller 8. Alternatively, the permanent magnets 6 can also be arranged on an inner surface of the folding roller cover 60.

[0056] Fig. 4 This shows a comparison of a rotation frequency of 81 on a worn folding roller with a rotation frequency of 82 on a good folding roller (which can be used as a standard). The comparison shows the rotation frequency of worn-out folding rollers.

[0057] It can be seen that the rotation frequency 81 of the worn folding roller decreases more slowly in contrast to the rotation frequency 82.

[0058] This means that the time until the worn folding roller comes to a stop (i.e., the standstill time / run-down time) is longer than with a good folding roller.

[0059] During the sealing process, the folding roller rotates with the cans. Once the folding process is complete, the folding roller rotates until it comes to a stop. The deceleration of the folding roller until it stops can be measured using the inventive method. The time until the folding roller comes to a stop is a characteristic of the roller's wear condition. This can indicate bearing wear, necessitating replacement of the folding roller.

[0060] Furthermore, the measurements allow for the monitoring of other defects. Not only can it be checked whether the folding roller lid is coming loose, but the quality of the fold can also be checked during the closing process.

[0061] The inventive method allows for the acquisition of current knowledge about the condition of machines and tools, thus preventing machine downtime due to defective tools. Data on tool quality can be collected, and production losses caused by poor folding, such as skidders, can be avoided.

[0062] The invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and brought about by those skilled in the art when practicing a claimed invention by studying the drawings, the disclosure, and the dependent claims. In the claims, the word "comprising" does not exclude any other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are repeated in different dependent claims does not mean that a combination of these measures cannot be used advantageously. Any reference numerals in the claims should not be interpreted as limiting the scope.

Claims

1. Method for monitoring folding tools (8, 9) for a capper (1000) for closing a container (100), the method comprising providing a folding tool (8, 9) and a monitoring device (20) for monitoring the folding tool (8, 9), the monitoring device (20) comprising a rotation sensor (21, 22) connected to the monitoring device (20) by which the rotation of the folding tool (8, 9) can be measured; rotating the folding tool (8, 9); monitoring the folding tool (8, 9) by measuring a time course of the rotation of the folding tool (8, 9) by the rotation sensor (21, 22).

2. Method according to claim 1, wherein the closure device (1000) is provided and comprises the folding tool (8, 9) and the monitoring device (20).

3. Method according to one of the preceding claims, wherein the rotation sensor (21, 22) is arranged on the folding tool (8, 9), in particular in the folding tool (8, 9).

4. Method according to one of the preceding claims, wherein the rotation sensor (21, 22) is arranged in such a way as to the folding tool (8, 9) that the rotation of the folding tool (8, 9) can be measured.

5. Method according to one of the preceding claims, wherein the rotation sensor (21, 22) is a Hall sensor (21, 22) and the folding tool (8, 9) in particular comprises a permanent magnet (6, 7).

6. Method according to one of the preceding claims, wherein the folding tool (8, 9) is a folding means (8, 9) rotatable about a folding axis (X).

7. Method according to claim 6, wherein the folding means (8, 9) is a folding roll (8) for folding a lid (101) onto the container (100).

8. Method according to one of the preceding claims, wherein the rotation sensor (21, 22) measures a rotation frequency of the folding tool (8, 9) and in particular monitors a change in the rotation frequency of the folding tool (8, 9).

9. Method according to one of the preceding claims, wherein the rotation of the folding tool (8, 9) is measured after completion of a closing process of the container (100) and / or the rotation of the folding tool (8, 9) is measured when the folding tool (8, 9) is not engaged with the container (100).

10. Method according to one of the preceding claims, wherein monitoring the folding tool (8, 9) comprises comparing the measured time course of the rotation of the folding tool (8, 9) with a standard.

11. Method according to claim 10, wherein a measured downtime of the folding tool (8, 9) is compared with the standard.

12. Device for carrying out a method according to one of the preceding claims comprising a folding tool (8, 9) and a monitoring device (20) for monitoring the folding tool (8, 9), wherein the monitoring device (20) comprises a rotation sensor (21, 22) connected to the monitoring device (20) by means of which the rotation of the folding tool (8, 9) can be measured.

13. Sealer for carrying out a method according to one of claims 1-12 comprising a folding tool (8, 9) for attaching a lid (101) to a container (100) and a monitoring device (20) for controlling and monitoring the sealer (1000), wherein the monitoring device (20) comprises a rotation sensor (21, 22) connected to the monitoring device (20) by means of which the rotation of the folding tool (8, 9) can be measured.

14. Sealer according to claim 13 comprising an arrangement (14) arranged in a working space (2) of the sealer (1000) with a plurality of sealing stations (1) comprising the folding tool (8, 9).

15. Sealer according to claim 13 or 14, wherein the rotation sensor (21, 22) is arranged on the folding tool (8, 9) and / or the sealer (1000) such that the folding tool (8, 9) can be monitored by measuring the rotation of the folding tool (8, 9) about a folding axis (X).

Images