Star wheel, blocked container handling installation and method for operating a star wheel

Abstract

The invention relates to a star wheel for a container handling installation having a carrier which can be rotatably driven and a plurality of grippers (1) movably arranged on the carrier, which are configured for transporting and transferring containers (2), the grippers (2) being configured to be guided at a transfer section (3) along a transfer path in a production mode. According to the invention, the grippers (1) are configured to be guided at the transfer section (3) along a avoidance path, set back from the transfer path, in a safety mode. The invention also relates to a blocked container handling installation having the star wheel, and to a method for operating the star wheel.

Description

[0001] Star wheel, blocked container treatment plant and method for operating a star wheel

[0002] Description:

[0003] The invention relates to a star wheel for a container processing system comprising a rotatably driven carrier and a plurality of grippers movably arranged on the carrier, which grippers are configured for transporting and transferring containers. The grippers are configured to be guided along a transfer path at a transfer section in a production facility. The invention further relates to a block-type container processing system comprising the star wheel and a method for operating the star wheel.

[0004] The container handling system is specifically designed for use in the beverage industry. A container handling system is typically comprised of a multitude of consecutive components that handle the containers. For example, a container handling system can consist of various container handling machines such as a blow molding machine, a labeling machine, a filling machine, a closing machine, and a coating machine. Appropriate guidance and transfer must be ensured within and between the individual machines.

[0005] It is common practice for an entire container processing plant or part of it to be interlocked. This means that the containers are continuously conveyed at a constant throughput, whereby the successive components are synchronized with one another and aligned at the transfer points so that a direct container transfer can take place. With an average throughput that remains constant, grouping can also be achieved using suitable star wheels, for example to coat groups of two to four containers together. In order to increase the distance between the containers while maintaining a constant throughput and thus increase the transport speed along the track, so-called pitch-delay star wheels are known.

[0006] The containers are transported, for example, using star wheels and carousels that are connected to one another, where a suitable transfer must then be provided.

[0007] Within the scope of the invention, bottles for beverages or other filling media can be handled, in particular. Particularly suitable PET bottles have a neck ring. During a grip change, grippers of successive devices can be arranged at different heights to grip the bottles above and below the neck ring. In this context, this is also referred to as over-neck and under-neck gripping. During such a grip change, the grippers can be guided at different heights to avoid collisions during transfer.

[0008] WO 2023 / 180415 A1 and WO 2003 / 1804241 disclose star wheels of this type with active grippers, which allow gripping at the same height during the transfer of containers, particularly bottles. During the transfer, the containers are released from the transferred grippers, guided along an intermediate support, and then actively gripped by the receiving gripper.

[0009] For proper operation, it is necessary for interlocked systems that consecutive components are synchronized with each other to ensure a controlled transfer. If synchronization is not achieved in an interlocked container handling system, the containers cannot be transferred as described. In some cases, even parts arranged at the same height in consecutive components such as star wheels and carousels may collide with each other. It should also be noted that in some designs, grippers engage in designated spaces during transfer, with other protruding components located adjacent to them.

[0010] Synchronization of consecutive components can be achieved, for example, through a common drive and a mechanical coupling. The synchronization is then determined by a mechanical coupling, for example, in the form of gears, a chain, or the like. The movement of components of a combined container handling system is then always synchronized thanks to the common drive and the mechanical coupling. However, the described mechanical coupling can result in disadvantages in terms of design freedom, energy efficiency, and construction effort.

[0011] The invention is based on the object of providing a star wheel that is particularly versatile while enabling safe use. Furthermore, a blocked container treatment system with the star wheel and a method for operating the star wheel are to be provided.

[0012] The subject matter of the invention and the solution to the problem are a star wheel according to patent claim 1, a blocked container treatment plant according to patent claim 12 and a method for operating a star wheel according to patent claim 15. Starting from a star wheel with the features of the preamble of patent claim 1, it is accordingly provided that the grippers are designed to be guided in a safety operation at the transfer section along an alternative path which is set back compared to the transfer path.

[0013] In this context, the present invention is based on the finding that, depending on the type of container transfer, there may be a risk of collision if synchronization is lost.

[0014] For example, if the star wheel is intended as a feeder for a labeling machine, the grippers of a conventional design could collide with components of the labeling machine if they are misaligned if they are lost. Similar considerations also apply in combination with other machines and components, especially if the grippers engage a free space or similar area during synchronized operation that is no longer available if synchronization is lost.

[0015] Within the scope of the invention, such a collision can be avoided by guiding the grippers along an alternative path at the transfer section during safety operation, which is offset far enough back from the transfer path to prevent a collision under all circumstances. Switching can occur, in particular, if synchronization is lost or not ensured.

[0016] Within the scope of the invention, the grippers are movable in such a way that they can be relocated from the transfer path to the avoidance path to such an extent that a collision is reliably avoided. It is understood that the containers will then not be transferred on the avoidance path. To enable re-starting, for example, the containers can be detached from the grippers as needed using a simple ejector or the like, or released from the grippers by a corresponding control system. A preferred embodiment is one in which the guidance of the grippers along the avoidance path causes the containers to be automatically ejected.

[0017] The transfer of the grippers from the transfer path to the bypass path can be accomplished in various ways. For example, an electric motor drive is possible, with each gripper then being provided with a dedicated electric motor as a changeover drive.

[0018] To enable the simplest and most reliable design possible, a preferred embodiment of the invention provides for the grippers to be redirected to the alternative path by a mechanical guide. In particular, it can be provided that the grippers are guided along the transfer section, at least in sections, by a mechanical guide even during actual production operation, with the mechanical guide then being switchable to provide production operation and safety operation.

[0019] This is possible, for example, by guiding the grippers along the transfer section by a control cam, with the control cam being movably arranged to provide both production mode and safety mode. The switchover between production mode and safety mode is then achieved by movement, and in particular, by shifting the control cam. It may be advantageous for the control cam to have an extended inlet and / or an extended outlet to combine the various movement options.

[0020] The control curve can be switched, for example, by shifting it in the radial direction.

[0021] If the switching is carried out with a control cam, only a suitable movement of the control cam must be ensured, whereby, for example, a switching drive acts on the control cam as a mechanical guide, so that not every gripper has to be equipped with its own switching drive.

[0022] A pneumatic cylinder, for example, is suitable as a changeover drive, which can be supplied with working compressed air, particularly via valves. The valves are then conveniently connected to a machine control system or a higher-level system control system, which is configured to determine the condition of the star wheel or its connected components.

[0023] The pneumatic cylinder design of the actuator is merely an example. The previously described control cam can also be driven by electric motors or similar devices.

[0024] Regardless of the specific design, the changeover drive can also have an end-position lock so that, with the exception of the changeover process itself, the transfer path on the one hand and the bypass path on the other hand are predefined as possible movement paths, and the movement then always occurs in a defined manner within this framework. The inventive design of the star wheel is also intended to enable safe operation in the event of any type of malfunction. To provide such a safety function, it is particularly expedient for the changeover drive to have a fail-safe feature. For an electric changeover drive or the valves of a pneumatic changeover drive, for example, an uninterruptible power supply can be provided to enable changeover even in the event of a power failure.An uninterruptible power supply (UPS) can also ensure that the previously described limit position locking of the changeover drive is possible under all circumstances. In this context, a sufficiently large tank may also be useful for providing the working air, so that sufficient working pressure is initially guaranteed for a sufficient duration in the event of a power failure in a pneumatic changeover drive.

[0025] Within the scope of the invention, the grippers are moved out of a potential collision and danger zone by the guide along the avoidance path, if necessary, particularly if synchronization is lost or at least not guaranteed in a blocked container handling system. The specific design of the grippers is not restricted by this. The grippers can be designed as passive grippers or as active grippers. The gripper is referred to as an active gripper if it performs an active opening and / or closing movement. In particular, two interacting arms can be provided which are moved relative to one another by an actively driven movement. If, on the other hand, two interacting arms are movable but are only moved, for example, by the insertion of the container, the gripper is a passive gripper.Particularly suitable are designs of the grippers as known from WO 2023 / 180415 A1 and WO 2023 / 180424 A1.

[0026] Accordingly, when the grippers are designed as active grippers, it is not only possible for two interacting arms to perform opening and closing gripping movements. According to one embodiment of the invention, the grippers are configured to perform an at least partially radial transfer stroke during a container transfer.

[0027] Return and / or holding devices can be connected to the grippers to keep them in a production position during production. Suitable return devices include springs such as coil springs, which urge the radially movable grippers toward the production position. The springs can then also be used to enable the previously described transfer stroke with a suitable guide.

[0028] Furthermore, the grippers can be moved back when guided along the compensation path against the force of return devices, so that after passing through the avoidance path, the grippers can be moved back to a normal position.

[0029] The transfer path and the bypass path guide the grippers differently at the transfer section, whereby the transfer path and the bypass path typically only extend over a comparatively small angular range at the transfer section relative to the entire circumference of the star wheel. It is preferably provided that the grippers are guided in the same way upstream and downstream, regardless of the switching between the transfer path and the bypass path.

[0030] The diverging paths of the transfer path and the bypass path and / or a control curve provided for switching can, for example, extend over an angular range between 25° and 55°, in particular between 30° and 45°. It should be noted that a control curve extending only over part of the circumference generally extends over a somewhat larger angular range with respect to the aforementioned paths, because the two paths then conveniently coincide again within the control curve.

[0031] It is understood that when transporting containers with the star wheel, containers are picked up, transported, and released again. A total of two transfer sections are provided for picking up and releasing, with at least one of the two transfer sections being designed as described to prevent collisions. Of course, it is also possible within the scope of the invention for the described measures to be provided at both transfer sections.

[0032] The invention also relates to a block-type container treatment system with the star wheel described above. The star wheel is then one of several components of the entire container treatment system.

[0033] The container treatment system preferably comprises at least two container treatment machines selected from the group consisting of a blow-molding machine, a labeling machine, a filling machine, a closing machine, and a coating machine. The star wheel can then be a component of a container treatment machine or, preferably, arranged between two consecutive container treatment machines. For example, the star wheel can be arranged between a blow-molding machine and a labeling machine, whereby, for the sake of a particularly compact design, the star wheel can be directly adjacent to a blow-molding wheel of the blow-molding machine and / or a labeling carousel of the labeling machine.

[0034] Finally, the invention also relates to a method for operating the star wheel, wherein containers, in particular PET beverage bottles, are picked up by the grippers at a first transfer section in a production plant, transported and delivered to a second transfer section, wherein during the changeover from the production operation to the safety operation, the grippers are diverted from a transfer path to a relocated alternative path by a machine or system control at at least one of the transfer sections.

[0035] For example, such a transfer is provided when synchronization is not present or at least not guaranteed during container transport. Synchronization and / or misalignment of grippers or the like during a transfer can occur, for example, if the star wheel and a machine adjacent to one of the transfer sections are driven by separate drives.

[0036] Thus, according to a preferred embodiment of the invention, the star wheel and the at least one adjacent machine are each driven by a servo motor, resulting in a comparatively simple design overall. A mechanical coupling of the drives or the like is not necessary. When the star wheel and the at least one adjacent machine start from a standstill, synchronization is generally not yet achieved during the start-up and acceleration phases. Asynchronicity or spatial misalignment of transfer devices can also be caused by malfunctions. In this case, safety mode is expediently provided. However, if synchronous operation and correct position assignment between the star wheel and the adjacent machine are determined, a switch from safety mode to production mode can take place.

[0037] The star wheel can, for example, be used to transfer PET beverage bottles to the labeling carousel of a labeling machine. During production, the grippers then transfer the PET beverage bottles to suitable receptacles on the labeling carousel of the labeling machine.

[0038] If synchronization is lost, the grippers could, for example, collide with the labeling carousel's receptacles, which could lead to damage.

[0039] Against this background, the invention then allows switching to the relocated bypass path, where the grippers are then retracted and cannot collide with parts of the labeling carousel. Accordingly, no transfer of picked-up PET beverage bottles takes place.

[0040] Depending on the status of the star wheel and labeling machine, either the transfer path or the bypass path is set up. When the star wheel and labeling machine are switched on, the bypass path is preferably active because synchronous movement cannot be guaranteed when approaching the components. As soon as all relevant components are running synchronously and are correctly aligned with regard to the position of grippers or similar, a transfer takes place.

[0041] If an asynchrony between the star wheel and the labeling carousel and / or an incorrect position is detected during operation, the system switches to the alternative path, and this position is then expediently locked. It can also be expedient to stop the star wheel, the labeling carousel, and possibly other connected system components or the entire interlocked container handling system. If the asynchrony and / or incorrect position is detected, the transfer of containers to the star wheel can also be expediently prevented. PET beverage bottles picked up by the star wheel can then be ejected, for example, by a stripper, by opening the grippers, or the like. As already explained above, a preferred embodiment is one in which the guidance of the grippers along the alternative path causes the containers to be automatically ejected.

[0042] Once synchronization and proper alignment are reestablished during continued rotation or after a standstill, the conveyor can be transferred to the production facility or transfer route again. However, it is advisable to ensure that all PET beverage bottles have been removed from the star wheel beforehand.

[0043] During a production stop, it may be useful to transfer to the alternative path after the star wheel has come to a standstill, so that subsequent handling is the same as during power-up. If a malfunction or interruption is due to a power failure, appropriate fail-safe measures are provided, as previously explained. An uninterruptible power supply may be particularly useful.

[0044] In principle, when operating a combined container handling system, it is also possible for the star wheel and the labeling carousel to be slowed down or stopped while maintaining synchronization. For example, it is conceivable that a malfunction in a combined container handling system could affect another machine. As long as synchronization is ensured between the labeling machine and the star wheel in question, production can continue there, with the transfer path configured.

[0045] The invention is explained below with reference to exemplary drawings. They show:

[0046] Fig. 1 a star wheel with a connected container treatment machine in a highly schematic production plant,

[0047] Fig. 2 shows the components according to Fig. 1 in a safety operation.

[0048] Figure 1 shows a highly schematic view of a star wheel for a container processing plant. The star wheel comprises a rotating, drivable support (not shown) and a plurality of grippers 1 movably arranged on the support. For clarity, only one gripper 1 is shown.

[0049] According to Fig. 1, the gripper 1 carries a container 2 in the form of a PET

[0050] Beverage bottle. In the embodiment shown in Fig. 1, the star wheel rotates counterclockwise, with the container 2 shown located at the beginning of a transfer section 3 with respect to the direction of movement, in order to be transferred to a downstream machine, for example, a labeling machine. The gripper 1 is accordingly located at the beginning of a control cam 4 that is fixed with respect to the rotation of the carrier but radially movable, with which the grippers 1 can be moved in the radial direction.

[0051] As also shown in Fig. 2, the individual grippers 1 are adjustable in the radial direction against return means 5 in the form of springs, wherein the gripper 1 shown in Fig. 1 is in a front position.

[0052] Fig. 1 shows a production operation in which the grippers 1 are guided along a transfer path at the transfer section 3. For this purpose, a reference path 6 is shown, which refers to a center point of a gripping receptacle 7 of the grippers 1 or of the containers 2 held at the gripping receptacle 7. At the transfer section 3, the reference path 6 corresponds to the transfer path to enable the transfer of the containers 2 in a known manner.

[0053] The control cam 4 has an extended inlet 8, an extended outlet 9 and a central sector 10 arranged between them. With regard to the production operation and the transfer path, the central sector 10 is provided so that the grippers 1, which are movable in the radial direction, release the containers 2 during transfer with a radial transfer stroke inwards without a collision. The transfer stroke can be seen in the reference path 6 as a deformation of a circular shape. In the production operation envisaged in Fig. 1, the star wheel shown moves synchronously and in the correct position with the downstream machine. In the event of misalignment and / or loss of synchronization, depending on the design, there is a risk of the grippers 1 colliding, which could cause damage.

[0054] In order to avoid such collisions, the control cam 4, which is fixed relative to the rotation of the star wheel, is movable in the radial direction and can be moved back radially in order to then, in a safety mode, move the grippers

[0055] 1 at the transfer section 3 along a relocated alternative route.

[0056] For this purpose, reference is made to Fig. 2. A guide roller 11 of the gripper 1 then comes into contact with the extended control cam 4 already in the inlet 8. Due to the then relocated control cam 4, the entire gripper 1 is displaced far back against the force of the return means 5, whereby the gripper receptacles 7 are guided correspondingly far behind the reference path 6.

[0057] According to Fig. 2, no container 2 is shown on the gripper 1. It is understood that by moving the grippers 1 back, the containers are not transferred to the following machine. Preferably, the guidance of the grippers 1 along the deflection path causes the containers 2 to be automatically ejected. The grippers 1 are thereby kept free for the resumption of proper operation. If the container

[0058] 2 is not removed directly in the transfer section 3, the container 2 can still be arranged on the gripper 1 in the configuration shown in Fig. 2.

[0059] By applying force to the grippers 1 by the return means 5, the grippers 1 are displaced outward again at the outlet 9 of the control cam 4, so that the transfer path and the avoidance path are then brought together again. The differing paths of the transfer path and the avoidance path can, for example, extend over an angular range between 15° and 65°, in particular between 25° and 50°.

[0060] Reference symbol

[0061] Gripper container transfer section control cam return means reference path gripper holder inlet

[0062] Expiry of middle sector leadership role

Claims

Patent claims:

1. Star wheel for a container treatment plant with a rotatably drivable carrier and a plurality of grippers (1) which are movably arranged on the carrier and which are designed for transporting and transferring containers (2), wherein the grippers (2) are designed to be guided along a transfer path at a transfer section (3) in a production operation, characterized in that the grippers (1) are designed to be guided along an alternative path which is set back relative to the transfer path at the transfer section (3) in a safety operation.

2. Star wheel according to claim 1, characterized in that the grippers (1) are guided along the transfer section (3) by a mechanical guide, wherein the mechanical guide is switchable to provide the production mode and the safety mode.

3. Star wheel according to claim 2, characterized in that the grippers (1) are guided along the transfer section (3) by a control cam (4), wherein the control cam (4) is movably arranged for the provision of the production operation and the safety operation.

4. Star wheel according to claim 3, characterized in that the control cam (4) has an enlarged inlet (8) and / or an enlarged outlet (9).

5. Star wheel according to one of the preceding claims, characterized in that a changeover drive is provided for the transfer between the production mode and the safety mode.

6. Star wheel according to claim 5, characterized in that the changeover drive has a pneumatic cylinder.

7. Star wheel according to claim 5 or 6, characterized in that the changeover drive has an end position lock.

8. Star wheel according to one of claims 5 to 7, characterized in that the changeover drive has a fail-safe device.

9. Star wheel according to one of the preceding claims, characterized in that the grippers (1) are designed as active grippers.

10. Star wheel according to one of the preceding claims, characterized in that the grippers (1) are designed to perform an at least partially radial transfer stroke during a container transfer.

11. Star wheel according to one of the preceding claims, characterized in that return and / or holding means (5) are connected to the grippers (1) in order to hold the grippers (1) in a production position during production operation.

12. Blocked container treatment plant with a star wheel according to one of the preceding claims and at least two container treatment machines selected from the group blow molding machine, labeling machine, filling machine, closing machine, Coating machine.

13. Blocked container treatment plant according to claim 12, wherein the star wheel is arranged on a labeling machine and in particular between a blow molding machine and a labeling machine.

14. Blocked container treatment plant according to claim 13, wherein the star wheel is directly adjacent to a blowing wheel of the blowing machine and a labeling carousel of the labeling machine.

15. Method for operating a star wheel according to one of claims 1 to 11, wherein containers (2) in the production operation are picked up by the grippers (1) at a first transfer section (3), transported and delivered to a second transfer section (3), wherein when changing from the production operation to the safety operation by a machine or system control at at least one of the transfer sections (3) the grippers (1) are diverted from a transfer path to a relocated alternative path.

16. The method according to claim 15, wherein the star wheel and a machine adjacent to one of the transfer sections (3) are driven by separate drives, wherein a changeover from the safety mode to the production mode takes place when synchronous operation and a correct position assignment between the star wheel and the adjacent machine is determined.

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