METHOD FOR DISCHARGED HOLLOW BODY FROM A MACHINING LINE FOR MACHINING HOLLOW BODY AND SYSTEM FOR EXECUTING THE METHOD

Description

[0001] The invention relates to processing lines for machining hollow bodies, wherein the hollow bodies correspond, for example, to preforms or containers. Preforms are hollow bodies that are produced from a thermoplastic material by a primary forming process, such as injection molding. Such preforms serve as blanks for the production of containers, such as plastic bottles, for example, for dispensing beverages. For this purpose, preforms are usually first temperature-conditioned, that is, brought to a temperature suitable for forming, and then formed, e.g., in a blow molding process, in which the previously tempered preform is expanded against an outer mold. The preform received in the outer mold is stretched axially, e.g., with a stretching bar, and a pressure fluid, e.g.,A gas is introduced into the preform to expand it under pressure until it assumes an inner contour of the outer shape. Such expanded and stretched preforms can then also be called containers. These containers are then filled with a liquid, such as a beverage, for example in a filling process.

[0002] It is also known that the forming process is carried out by the filling material being fed in under forming pressure, meaning that the expansion of the preform into the container occurs simultaneously with the filling. It is also known that preforms are subjected to further treatments or processing before their forming, e.g., sterilization, or that fully formed containers undergo further treatments or processing, e.g., labeling or sealing after filling. These treatment processes are typical examples of processes that are carried out individually or sequentially in a production line.

[0003] The machining of hollow bodies takes place in a machining line, for example, in several machining steps. To check whether a machining step along the machining line has been carried out correctly, one or more inspection devices are arranged along the line to check the characteristics of the hollow body. Inspection devices can also be positioned temporally and spatially before a machining step to determine, for example, the suitability of the hollow body for the upcoming machining process. This prevents hollow bodies identified as defective from entering a processing station, as such defective hollow bodies could otherwise cause significant disruptions.

[0004] Inspection equipment is typically associated with rejection units. These units serve to remove inspected hollow bodies that are identified as defective from the processing line. For example, the inspection of the opening of a hollow body might look for potential deformation or a defective sealing surface where, for instance, a filling element is intended to attach. If such a deformation is detected, preventing, for example, the reliable insertion of a transport mandrel, or if a defective sealing surface prevents the reliable and pressure-tight attachment of a filling nozzle, the defective hollow body can be prevented from entering a processing or transport unit before it is damaged or destroyed due to the defect.This could occur if a part falls off a transport mandrel or transport clamp, or if a poorly fitting filling nozzle cannot deliver the product under pressure, causing it to splash around. Both of these could lead to undesirable malfunctions and associated production downtime.

[0005] Accordingly, hollow bodies identified as defective by the inspection device are reported to a rejection unit so that this unit can remove the defective hollow body from the processing line. According to the current state of the art, it sometimes happens that an error occurs during the rejection process for removing a defective hollow body from the processing line, causing the defective hollow body to be transported further along a conveyor direction. This is detected by a rejection evaluation unit, and the processing line is stopped so that the hollow body can be removed manually. Removal is necessary because, depending on the type of defect, defective hollow bodies can lead to serious problems or even damage to downstream components of the processing line.

[0006] According to this, an unsuccessful rejection process results in downtime for the entire processing line, during which processing cannot continue. Such downtime must be avoided, as a complete production stoppage leads to economic losses. Furthermore, restarting production is a complex process that sometimes requires significant personnel resources. In some cases, it is also necessary to run certain processing equipment empty during a production stoppage, as otherwise further damage is likely.

[0007] In the priority-establishing German patent application, the German Patent and Trademark Office searched the following documents: DE 10 2016 113 006 A1 and DE 10 2020 103 583 A1.

[0008] Furthermore, document US 2022 / 0307989 A1 discloses a system and method for the optical inspection of preforms made of thermoplastic material. The system comprises a conveyor belt with lateral guides that hold the preforms at their flanges and transport them sequentially along an inspection path. Along this path is an inspection station with at least one inspection camera that captures image data of one preform at a time. The conveyor belt is designed to support two operating modes: one for preforms of a first size and one for a second size. An actuator allows switching between these two configurations.

[0009] Document US 2022 / 0032528 A1 discloses a method for handling immobilized preforms that are fixed in a heating station during a production interruption. The preforms follow a production stream, and the heating station comprises a conveying system and a heating chamber enclosed by at least one array of monochromatic electromagnetic radiation emitters. The method provides for removing cold preforms, which were immobilized before irradiation by the emitters, from the production stream and feeding them into a recycling stream. Hot preforms, which were wholly or partially exposed to the radiation, are fed into a separate reject stream.

[0010] Furthermore, document US 2017 / 0252960 A1 discloses a device and method for transporting preforms in the area of ​​a blow molding machine, in particular a sorting device for transporting preforms made of thermoplastic material. This device comprises a transport wheel with several receptacles distributed around its circumference, each receptacle holding and transporting a preform. A guide ring runs section by section around the transport wheel and holds the preforms in a suspended position between the wheel and the ring. A selection unit with a pivoting ejector star, which has several ejector arms, enables the targeted removal of individual preforms from the receptacles. The first ejector arm prevents the preforms from unintentionally falling out when at rest. Upon rotation, a subsequent second ejector arm selectively ejects a preform to be removed from its receptacle.After that, this arm takes over again to secure the passing preforms against falling out.

[0011] The object of the present invention is therefore to address the problems of the prior art. In particular, a way is to be found to avoid a downtime of a processing line when the rejection of a defective hollow body has been unsuccessful. In any case, an alternative to what is known from the prior art is to be found.

[0012] The invention relates to a method for removing defective hollow bodies from a processing line according to claim 1.

[0013] The invention relates to a method for removing defective hollow bodies from a processing line used for processing hollow bodies.

[0014] According to the invention, hollow bodies are in particular preforms or containers. Preforms are used to manufacture containers from a thermoplastic material, such as polyethylene terephthalate, or PET for short, and are produced in a preliminary step prior to a forming process. Preforms are produced, for example, by conventional injection molding. To produce containers, such as bottles, the finished preforms are first heated, in particular by infrared emitters, and then transferred into an outer mold.

[0015] Single-stage processes are also known, in which the preform is fed into the forming process immediately after its injection molding production. In two-stage processes, the injection molding production and the forming are separated in time, so that the forming does not take place immediately after injection molding, but rather the manufactured preform is first cooled and then heated to a forming temperature at a later time.

[0016] Both single-stage and two-stage processes are well known in the prior art. Various forming processes are also generally known in the prior art, both with and without the use of a drawing bar. It is also known in the prior art to use a gaseous fluid, e.g., compressed air, or a liquid forming fluid, e.g., a filling material, in these forming processes.

[0017] A container produced from a preform, as described above, using a gaseous forming fluid, can be used, for example, for filling beverages. Accordingly, the invention also relates to containers, such as bottles, which are particularly well-made from preforms. The hollow bodies preferably comprise hollow bodies made of a thermoplastic material, e.g., PET. The preforms are also referred to as "preforms".

[0018] A processing line typically consists of a series of consecutive devices for processing hollow bodies, but it can also consist of just one device. Such processing devices include, for example, equipment for carrying out the aforementioned forming process. Other devices in the processing line can include filling stations for the hollow bodies, for example with a beverage, devices for labeling the hollow bodies, and devices for sealing the hollow bodies. Sorting devices, cleaning devices, or sterilizing devices can also be considered such equipment. The above list of devices is not exhaustive and is intended as an example only.

[0019] The individual devices of a processing line are connected by conveying devices of a conveying system, which may also include conveying devices within the processing devices themselves, in order to convey the hollow bodies preferably continuously from one end of the processing line to the other in a single conveying direction. Conveying devices of the conveying system thus correspond to conveying devices within processing devices of the processing line or conveying devices that serve to transport the hollow bodies from one processing device to the next between individual processing devices of the processing line. A conveying device comprises, for example, several grippers or holders moving in the conveying direction, each for holding a hollow body. A conveying device can also correspond to a conveyor belt.Typical conveying devices include transport wheels with circumferentially spaced conveying pockets or clamps mounted on them, or conveying mandrels, or circulating conveyor chains with transport mandrels as chain links, as are known, for example, for heating devices for preforms. This list is also purely exemplary and not exhaustive. A large number of such conveying devices are known in the prior art.

[0020] Machining hollow bodies therefore encompasses all steps that can be performed on these hollow bodies within a production line. This includes heating, forming, filling, labeling, marking, sealing, and similar processes. This list is purely exemplary and not exhaustive.

[0021] According to the invention, the method comprises conveying several hollow bodies along the processing line in a conveying direction. Furthermore, each hollow body is inspected by a first inspection device of the processing line. An inspection device includes, for example, a camera device with which an image of the hollow body is captured. The inspection device can also utilize any other or additional measuring means and methods to, for example, detect a surface, a wall, a shape, or another property of the hollow body. Such inspection devices are also known in the prior art in numerous forms.

[0022] An example of the arrangement and function of an inspection device is one that, after the preforms have been transferred to the blow molding machine, examines them for defects, for example, in the neck area. Features that are inspected include, for example, areas of the sealing surfaces, sections of the thread, areas of the handling ring, contaminants in the base or inside the hollow body, or the geometric shape of the hollow body. For example, incorrectly curved preforms that could come into contact with heaters, such as infrared emitters, during heating are detected. Furthermore, it is possible to examine the color and length of the preform on a deflection wheel of a heating device, or even its side surface.

[0023] Furthermore, the process includes determining whether the hollow body inspected by the inspection device is defective or defect-free. This determination is performed by a first evaluation unit assigned to the first inspection device. An evaluation unit is therefore considered a component of the inspection device or corresponds, for example, to a part of a control system for managing the process. In this system, a processor uses data acquired by the inspection device, such as image data, to determine whether the inspected hollow body meets the desired requirements with respect to one or more characteristics.In the case of image data, the evaluation unit can, for example, include image processing in which the image captured by the hollow body is compared with a reference image, or geometric data is extracted from the image captured by the hollow body and compared with reference data. The evaluation unit can be integrated into the inspection device, located directly on the inspection device, or located remotely from the inspection device, e.g., centrally in an area where other evaluation or control units are located.

[0024] Furthermore, the invention relates to the execution of a first rejection process. The rejection process serves to remove a hollow body identified as defective by the first evaluation unit from the processing line. The first rejection unit is arranged following the first inspection device in the conveying direction, e.g., immediately after it or at some distance. A rejection unit serves to remove a hollow body from the sequence of hollow bodies. Ejectors, in which hollow bodies identified as defective are mechanically ejected, are known, for example. It is also known that hollow bodies identified as defective are ejected from the conveying system with a burst of compressed air. Ejection from the conveying system by a lever using a rejection unit is also possible. According to another example, rejection is achieved by dropping the preform identified as defective, e.g.,by opening a pair of pliers or by releasing a holding force of a holding device of the conveying system that is holding a defective hollow body.

[0025] The first discharge unit is therefore arranged downstream of the first inspection device in the conveying direction, the invention being not limited to the first discharge unit being arranged immediately or directly downstream of the first inspection device. "Downstream of the first inspection device" therefore simply means that the first discharge unit is arranged downstream of the first inspection device in the conveying direction along the processing line, wherein, according to particular embodiments, for example, one or more components, such as processing devices, may be arranged between the first inspection device and the first discharge unit.

[0026] According to the procedure, the next step involves checking with a first rejection evaluation unit whether the initial rejection process was successful or unsuccessful. A successful rejection process, therefore, refers to the execution of a first rejection process that resulted in the removal of the hollow body identified as defective from the processing line. An unsuccessful first rejection process, therefore, corresponds to a first rejection process in which the hollow body identified as defective continues to be conveyed along the processing line by the conveyor system despite the execution of the first rejection process.

[0027] According to the procedure, the next step involves sending a first signal indicating a failed diversion attempt if the initial diversion process was unsuccessful. This first signal, therefore, indicates a failed diversion attempt and is sent from the first diversion evaluation unit to a second diversion unit. The second diversion unit is positioned downstream of the first diversion unit in the conveying direction. In practice, this sending of a first signal to a second diversion unit can mean, for example, that a control unit of the second diversion unit receives a signal indicating that the diversion attempt of the first diversion unit was unsuccessful. This control unit of the second diversion unit, e.g., a control module, does not have to be directly integrated into the second diversion unit but can also be located remotely.It is logically assigned to it in that it takes over the control of the second discharge unit.

[0028] Furthermore, according to the procedure, a second rejection process is carried out with the second rejection unit to remove the hollow body identified as defective from the processing line if the first signal indicating the rejection attempt is received by the second rejection unit. Therefore, if the second rejection unit receives the signal from the first rejection evaluation unit indicating a rejection attempt, i.e., an unsuccessful first rejection process, a second rejection process is carried out with the second rejection unit.

[0029] This process provides a second rejection step to remove defective hollow bodies that could not be successfully rejected in the first step. This increases the probability of successfully removing a defective hollow body from the processing line after two rejection attempts. As a result, the number of production line stops required for the manual removal of defective hollow bodies can be reduced. The problems associated with stopping or halting the production line can thus be mitigated.

[0030] According to a first embodiment, a second rejection evaluation unit is provided, which is assigned to the second rejection unit. The second rejection evaluation unit checks whether the second rejection process was successful or unsuccessful. The second rejection evaluation unit therefore checks whether the hollow body identified as defective by the first inspection device has been removed from the processing line, i.e., from the conveyor system, and thus the second rejection process was successful, or whether the hollow body identified as defective by the first inspection device continues to be conveyed through the conveyor system and remains in the processing line, i.e., the second rejection process was unsuccessful.

[0031] According to this embodiment, a second signal is generated by the second rejection evaluation unit, indicating a failed rejection attempt by the second rejection unit if the second rejection process has been unsuccessful. This signal is then sent by the second rejection evaluation unit to a third rejection unit. The third rejection unit is positioned downstream of the second rejection unit in the conveying direction. Thus, a third rejection process can be executed by the third rejection unit based on the second signal. According to an alternative to this embodiment, the processing line is stopped if the second rejection evaluation unit detects a failed second rejection process. Stopping the processing line serves, for example, to manually remove the hollow body identified as defective from the processing line.

[0032] By providing a second signal for a third ejection unit for a third ejection process, the probability of safely removing a hollow body identified as defective from the processing line is further increased, or by stopping the process, it is ensured that the hollow body identified as defective and still in the processing line despite two ejection attempts does not, for example, cause problems in a processing step in a processing device of the processing line.

[0033] According to another embodiment, the second discharge unit follows directly after the first discharge unit or the first discharge evaluation unit associated with the first discharge unit in the conveying direction of the processing line. The second discharge unit thus follows directly after the first discharge unit and the first discharge evaluation unit if these two units are designed as separate devices and, for example, arranged one after the other in the conveying direction.

[0034] The rejection evaluation unit can, for example, include a light barrier that checks in the processing line whether the hollow body identified as defective is no longer present. Alternatively, the rejection evaluation unit can be located on a branch that carries rejected hollow bodies, so that the rejection evaluation unit would not be part of the conveyor system itself, but rather a branch of the conveyor system. In this case, the second rejection unit follows directly after the first. According to another alternative, the rejection unit and the rejection evaluation unit can be designed as a single, integrated unit.

[0035] The second rejection process can therefore be carried out immediately after the unsuccessful execution of the first rejection process, if necessary. Consequently, no further processing or inspection steps are required between the first and second rejection units. "Immediately" means that the first rejection unit follows directly after the second rejection unit in the conveying direction, and preferably the first and second rejection units are provided on a common conveying system. Therefore, the process can be implemented by inserting a second rejection unit into an existing processing line after the first rejection unit. The additional installation effort for the second rejection unit reduces the likelihood of the processing line stopping.

[0036] According to a further embodiment, the second discharge unit follows a second inspection unit in the conveying direction. The second inspection unit is preferably arranged after the first inspection unit and after the first discharge unit. According to a particular embodiment, a first inspection unit, followed by a first discharge unit, preferably followed by at least one processing unit, followed by a second inspection unit, and then the second discharge unit can be arranged along the conveying direction. In any case, a second inspection unit is arranged between the first discharge unit and the second discharge unit.

[0037] According to the latter embodiment, a second rejection unit, assigned to a second inspection device, is used for the process. The second rejection unit, which was previously used in an existing processing line to reject hollow bodies identified as defective by the second inspection device, is thus also used, or additionally used, to reject hollow bodies identified as defective by the first inspection device if a first rejection attempt has failed. Therefore, by providing the second rejection unit with the first signal indicating the failed rejection attempt, the process can be executed without having to integrate an additional rejection unit into an existing processing line. The second rejection unit thus functions, on the one hand, to reject the hollow bodies identified as defective by the second inspection device. This can be understood as its primary function.On the other hand, the second rejection unit also removes hollow bodies that were identified as defective by the first inspection unit but could not be rejected by the first rejection unit. The second rejection unit performs this additional task when it receives a corresponding signal, namely when the first rejection evaluation unit determines that the first rejection attempt has failed.

[0038] According to a further embodiment, the first inspection device checks at least one first feature of the hollow body. The second inspection device checks at least one second feature of the hollow body. The second feature differs from the first feature. The first and second features are important for a subsequent processing step, for example, in that their non-fulfillment can lead to problems or malfunctions. A hollow body should therefore exhibit a specific degree of different features depending on the processing step. Features include, for example, size, shape, orientation, wall thickness, and similar properties of the hollow body. The two inspection devices thus serve to check different features of the hollow body.

[0039] According to this embodiment, the method further comprises detecting with the first inspection device or its evaluation unit whether the hollow body corresponds to a defective hollow body or a non-defective hollow body with respect to the first feature, and detecting with the second inspection device or its evaluation unit whether the hollow body corresponds to a defective hollow body or a non-defective hollow body with respect to the second feature. A second rejection process is therefore carried out with the second rejection unit if it is detected that the hollow body is defective with respect to the second feature, or if it is detected that the hollow body is defective with respect to the first feature and, in addition, a first rejection process was unsuccessful.

[0040] An existing second rejection unit can therefore be used to reject defective hollow bodies identified by the second inspection device after intended use, but also to increase the probability of a successful rejection attempt of hollow bodies identified as defective by the first inspection device.

[0041] According to a further embodiment, several inspection devices, several discharge units, and preferably several processing devices are arranged along the conveying direction, and a control system for controlling at least the several inspection devices and discharge units is provided. This control system is to be understood as a control device.

[0042] The control system can activate several or all of the multiple rejection units following one of the multiple inspection devices in the conveying direction to execute a rejection process for a defective hollow body. Activation continues until the rejection of a hollow body identified as defective is successful. Accordingly, the control system is configured to activate multiple or all rejection units, particularly with a signal indicating failed rejection attempts, so that a defective hollow body identified as defective with respect to a feature by one of the inspection devices will be rejected until the rejection process is successful.

[0043] Preferably, one or more predefined criteria are stored in the control system. A predefined criterion is preferably stored for each or several of the machining units. The criterion indicates which features of the hollow body, in particular features that are inspected by an inspection device before machining with the respective machining unit, must be free of defects or may be defective for the respective machining unit(s). Thus, each machining unit or multiple machining units is assigned one of several predefined criteria, indicating which features of a hollow body must be free of defects or may be defective in order for machining to be carried out in the machining unit.

[0044] The criterion therefore indicates whether machining with the machining equipment could lead to a fault in the machining equipment if a hollow body has a defect with respect to a feature, or whether such a defect will not cause any problems during machining with the machining equipment. The control system stops the machining line before a defective hollow body, which does not meet the criterion of a machining equipment, reaches the corresponding machining equipment.

[0045] According to this embodiment, rejection processes for defective hollow bodies are carried out until the defective hollow body is conveyed to a processing unit whose criteria it does not meet, i.e., it has a defect with respect to a feature that could lead to a problem in the processing unit. In this case, the processing line stops to avoid a problem in the processing unit.

[0046] Accordingly, the invention serves to perform continuous rejection tests for defective hollow bodies, preferably without stopping the processing line, taking into account that defective hollow bodies that remain in the processing line even after several rejection tests do not necessarily lead to problems in the processing equipment. The type of defect and the type of processing equipment are taken into account.

[0047] According to a further embodiment, if a defective hollow body is removed from the line or after the defective hollow body is detected, a processing station associated with the position of the defective hollow body in one or all processing units is deactivated. Accordingly, processing units are provided that have several processing stations. Each processing station processes one hollow body, and several hollow bodies can be processed essentially in parallel within a single processing unit with multiple processing stations. If a hollow body is removed from the processing line, i.e., removed from the line, there is no longer a hollow body to be processed at the original position of the defective hollow body. The processing station associated with this position is therefore deactivated according to this embodiment.

[0048] For example, a series of containers are conveyed consecutively in the conveyor system, with one position having no container because the container that was located there was rejected due to a defective feature. If the containers are now fed into a processing unit, such as a filling unit, the processing station associated with the position of the missing container would, if it were not deactivated, attempt to discharge liquid to the position where the defective container was previously located in the conveyor system. The liquid would thus be discharged into thin air. According to the preferred embodiment, this is avoided by deactivating the affected filling station when no container is present.In this example, "deactivated" means that no filling process is carried out, or more generally, that the processing step of the processing station is not executed.

[0049] Even if a machining unit were to automatically perform a check for the presence or absence of a hollow body at its machining stations, this check could be faulty. Therefore, by deactivating the machining stations as soon as a faulty hollow body is detected, a double safeguard against accidental machining of an unoccupied position can be achieved.

[0050] Furthermore, the invention comprises a control system for diverting defective hollow bodies from a hollow body processing line. The control system includes a first evaluation unit associated with a first inspection device. The evaluation unit is configured to detect whether a hollow body inspected by the inspection device is defective or defect-free. The evaluation unit is also configured to control a diverting unit that follows the inspection device in a conveying direction. The control system serves to control the diverting unit to execute a first diverting process to remove a detected defective hollow body from the processing line.

[0051] Furthermore, a first rejection evaluation unit of the control system is provided, which is configured to check whether the first rejection operation was executed successfully or unsuccessfully. This first rejection evaluation unit is also configured to send a first signal indicating a rejection attempt failure to at least one second rejection unit following the first in the conveying direction if the first rejection operation was executed unsuccessfully. Thus, the rejection evaluation unit serves to control the execution of a second rejection operation with a second rejection unit that received the first signal indicating the rejection attempt failure, in order to reject any detected defective hollow body from the processing line during the execution of the second rejection operation.

[0052] The control system is further configured to execute a procedure according to one of the aforementioned embodiments.

[0053] Furthermore, the invention relates to a system for diverting defective hollow bodies from a machining line for machining hollow bodies. The system preferably comprises a control system according to one of the aforementioned embodiments. Preferably, the system is configured to execute one embodiment of the method.

[0054] The system according to the invention comprises a conveying system for transporting several hollow bodies along the processing line. The conveying system preferably comprises several conveying devices. Furthermore, the system comprises a first inspection device for inspecting each hollow body and a first evaluation unit associated with the first inspection device. The evaluation unit serves to determine whether the hollow body being inspected is defective or non-defective.

[0055] Furthermore, the system includes a first rejection unit, which follows the first inspection unit in the conveying direction. The first rejection unit is used to execute an initial rejection process to remove any hollow body identified as defective from the processing line. The system also includes a first rejection evaluation unit, which is assigned to the first rejection unit. This evaluation unit verifies whether the first rejection process was successful or unsuccessful.

[0056] Furthermore, the system includes at least one second rejection unit following the first rejection unit in the conveying direction. The first rejection evaluation unit is configured to send an initial signal indicating a failed rejection attempt to the second rejection unit if the first rejection operation is unsuccessful. Upon receiving the initial signal indicating the failed rejection attempt, the second rejection unit is configured to execute a second rejection operation to remove the detected defective hollow body from the processing line.

[0057] According to one embodiment of the system, a second rejection evaluation unit is provided, which is associated with the second rejection unit. The second rejection evaluation unit serves to check whether the second rejection process was executed successfully or unsuccessfully. The system also includes a third rejection unit following the second rejection unit, wherein the second rejection evaluation unit is configured to send a second signal, indicating a failed rejection attempt, from the second rejection evaluation unit to the third rejection unit. According to an alternative to providing a third rejection unit and the second signal, the second rejection evaluation unit is configured to stop the processing line to allow for the manual removal of the defective hollow body identified for rejection.

[0058] According to another embodiment, the second discharge unit follows directly after the first discharge unit or the first discharge evaluation unit associated with the first discharge unit in the conveying direction. According to a further embodiment, the system includes a second inspection device. The second discharge unit follows the second inspection device in the conveying direction, so that the second inspection device is thus arranged after the first discharge unit and before the second discharge unit in the conveying direction.

[0059] According to a further embodiment of the system, the first inspection unit is configured to check at least one first feature of the hollow body. The second inspection unit is configured to check at least one second feature of the hollow body that differs from the first feature. The second evaluation unit is configured to determine whether the hollow body is defective or non-defective with respect to the second feature. The system is configured to execute a second rejection operation with the second rejection unit to remove a defective hollow body detected with respect to the second feature, and a defective hollow body detected with respect to the first feature, in the event of a first signal indicating a failed rejection attempt.

[0060] According to another embodiment of the system, it comprises several inspection units, each with an assigned evaluation unit. Each evaluation unit is configured to control several or all of the discharge units following the respective inspection unit in the conveying direction.

[0061] According to another embodiment of the system, the system comprises one or more processing devices arranged along the conveyor line to form a processing line and to process hollow bodies.

[0062] Further embodiments are shown in the exemplary embodiments explained in more detail in the figures. These show: Fig. 1 shows a system according to an embodiment and Fig. 2 shows the steps of a method according to an embodiment.

[0063] Fig. 1Figure 10 shows a schematic representation of a system 10 for removing defective hollow bodies 36 from a machining line according to an exemplary embodiment. The system 10 comprises a machining line 12 that includes several machining units 14a, 14b, 14c for machining hollow bodies 36. For clarity, the machining units 14a, 14b, 14c are shown here as blocks. Each machining unit 14a, 14b, 14c has an internal conveying device 16 to convey hollow bodies 36 through the respective machining unit 14a, 14b, 14c. Further conveying devices 18a, 18b, 18c are shown outside the processing devices 14a, 14b, 14c to convey hollow bodies 36 from one processing device 14a, 14b, 14c to the next processing device 14a, 14b, 14c in a conveying direction 20.Between the internal conveying facilities 16 and the conveying facilities 18, 18b, 18c, transfer points 21 are provided for the transfer of the hollow bodies 36 between the conveying facilities.

[0064] All conveying devices 16, 18a, 18b, 18c together form a conveying system 22 with a conveying section 24. Each of the conveying devices 18a, 18b, 18c is equipped with an inspection device 26a, 26b, 26c with an associated evaluation unit 28a, 28b, 28c, a discharge unit 30a, 30b, 30c, and a discharge evaluation unit 32a, 32b, 32c. These serve to check the properties of the hollow bodies, e.g. B. to check the result of a previous processing step in one of the processing devices 14a, 14b, 14c during the transfer of the hollow bodies 36 from one processing device 14a, 14b, 14c to the next processing device 14a, 14b, 14c and, if necessary, to reject defective hollow bodies 36.

[0065] Accordingly, a device 34 is provided with which hollow bodies 36 in the form of preforms 38 are introduced from a supply 40 into a first conveying device 18a. For clarity, grippers or holding devices that hold the hollow bodies 36, as well as the hollow bodies 36 themselves, are not shown. Along the conveying direction 20, the hollow bodies 36 are then inspected by a first inspection device 26a, whereby a first evaluation unit 28a detects whether the inspected hollow body 36 is defective or non-defective. In a first rejection unit 30a, hollow bodies 36 identified as defective are rejected, and in a first rejection evaluation unit 32a, it is checked whether a first rejection process with the first rejection unit 30a was successful or unsuccessful.The first inspection device 26a checks the hollow bodies 36 designed as preforms 38, for example, for geometric properties, in order to ensure that the preforms 38 can be formed into containers in a first processing device 14a, which corresponds, for example, to a blow molding device 42.

[0066] After passing through this first processing unit 14a, the hollow bodies 36, now configured as containers 44, are inspected again via the conveyor unit 18b. For this purpose, a second inspection unit 26b with an associated second evaluation unit 28b, a second discharge unit 30b, and a second discharge evaluation unit 32b are provided. The initially empty container 44 is checked again for its geometry by the second inspection unit 26b in order to be labeled in a second processing unit 14b, which corresponds, for example, to a labeling device 46. The conveyor unit 18c then conveys the labeled hollow bodies 36 to another processing unit 14c, which is, for example, a filling unit 49. A third inspection unit 26c with an associated third evaluation unit 28c, a third discharge unit 30c, and a third discharge evaluation unit 32c are arranged on the conveyor unit 18c.Further processing equipment 14a, 14b, 14c and conveying equipment 16, 18a, 18b, 18c may follow until the processing of the hollow body 36 is completed, but are not shown for clarity.

[0067] Furthermore, a control unit 47 of system 10 is provided, which controls the processing line 12. The evaluation units 28a, 28b, 28c, as well as parts of the rejection evaluation units 32a, 32b, 32c, are preferably part of the control unit 47, but are shown here as external components for clarity. The control unit 47 is configured to generate a first signal 48 and send it to the second rejection unit 30b in the event of an unsuccessful execution of a first rejection operation detected by the first rejection evaluation unit 32a.

[0068] The first signal 48 indicates a failed rejection attempt and prompts the second rejection unit 30b to reject a defective hollow body 36 detected by the first inspection unit 26a and the first evaluation unit 28a, if it was not successfully rejected by the first rejection unit 30a. Furthermore, the control unit 47 is also connected to the second rejection evaluation unit 32b and configured to generate a second signal 50 if a second rejection process 78 with the second rejection unit 30a also fails, as detected by the second rejection evaluation unit 32b. The second signal 50 is fed to the third rejection unit 30c to execute a third rejection process in order to reject the hollow body 36, which was detected as defective by the first inspection unit 26a and the first evaluation unit 28a.

[0069] The control unit 47 is also configured to activate the third discharge unit 30c with the second signal 50 even if the second inspection unit 26b with its associated evaluation unit 28b detects a defective hollow body 36 that could not be discharged by the second discharge unit 30b. This is detected by the second discharge evaluation unit 32b. Thus, the control unit 47 is configured to activate discharge units 30a, 30b, 30c arranged downstream of each inspection unit 26a, 26b, 26c in the conveying direction 20 until a discharge process has been successfully carried out for the hollow body 36 identified as defective.

[0070] Fig. 2Figure 60 shows the steps of a method for diverting defective hollow bodies 36 from a processing line 12 for processing hollow bodies 36 according to an exemplary embodiment. In step 60, hollow bodies 36 are conveyed along the processing line 12 in a conveying direction 20. In step 62, each hollow body 36 is inspected by a first inspection device 26a of the processing line 12. In step 64, it is determined whether the inspected hollow body 36 is defective or non-defective. This is done by a first evaluation unit 28a. Furthermore, a first diversion process 66 is carried out by a first diversion unit 30a to divert a hollow body 36 identified as defective from the processing line 12.

[0071] In step 68, a first discharge evaluation unit 32a checks whether the first discharge operation 66 was successful or unsuccessful. In step 70, a first signal 48 indicating a discharge failure attempt is sent from the first discharge evaluation unit 32a to at least one second discharge unit 30b following the first discharge unit 30a in the conveying direction 20 if the first discharge operation 66 was unsuccessful. Subsequently, in step 72, the hollow body 36 is processed by a first processing device 14a.

[0072] In step 74, the hollow body 36 is then inspected by a second inspection device 26b, and in step 76, a second evaluation unit 28b determines whether the inspected hollow body 36 is defective. A second rejection process 78 is executed with a second rejection unit 30b if the first signal 48 was received by the second rejection unit 30b or if the hollow body 36 was identified as defective by the second evaluation unit 28b in step 76.

[0073] In a further step 80, a second rejection evaluation unit 32b checks whether the second rejection process 78 was successful. If the second rejection process 78 was unsuccessful and a criterion for the next processing step of a second processing unit 14b is not met, the processing line 12 is stopped in step 82. Otherwise, a second signal 50 is generated, and a further processing step is executed in a second processing unit 14b in step 82.

[0074] After step 82, another inspection is carried out with a third inspection unit 26c in step 84, whereby in step 86 it is checked whether the hollow body 36 corresponds to a defective hollow body 36 or a non-defective hollow body 36. If the hollow body 36 corresponds to a defective hollow body 36, a third rejection process 88 is carried out by a third rejection unit 30c. The third rejection process 88 is also carried out if the second signal 50 is received by the third rejection unit 30c, emitted by the second rejection evaluation unit 32b. The procedure continues in this way until the processing of the hollow body 36 is completed. Reference sign

[0075] 10 System 12 Processing line 14 First processing unit 14b Second processing unit 14c Third processing unit 16 Conveyor 18 First conveying device 18b Second conveying device 18c Second conveying device 20 Conveyor direction 21 Transfer points 22 Conveyor system 24 Conveyor section 26 First inspection unit 26b Second inspection unit 26c Third inspection unit 28 First evaluation unit 28b Evaluation unit 28c Evaluation unit 30 First discharge unit 30b Second discharge unit 30c Third discharge unit 32 First discharge evaluation unit 32b Second discharge evaluation unit 32c Third discharge evaluation unit 34 Device 36 Hollow body 38 Preforms 40 Stock 42 Blow molding device 44 Container 46 Labeling device 47 Control 48 First signal 49 Filling device 50 Second signal 60 Conveying hollow bodies 62 Checking hollow bodies with first inspection device 64 Detecting,66 First rejection process 68 Check whether the first rejection process was successful or unsuccessful 70 Send a first signal indicating a failed attempt 72 Execute processing of the hollow body 74 Check hollow body 76 Detect whether the tested hollow body corresponds to a defective hollow body 78 Second rejection process 80 Check whether the second rejection process was successful 82 Stop processing line 84 Inspection with a third inspection device 86 Check whether the hollow body corresponds to a defective hollow body or a defective hollow body 88 Third rejection process

Claims

1. Method for rejecting defective hollow bodies (36), in particular preforms (38) or containers (44), from a processing line (12) for processing hollow bodies (36), comprising: - conveying a plurality of hollow bodies (36) along the processing line (12) in a conveying direction (20), - testing of each hollow body (36) with a first inspection device (26a) of the processing line (12), - determining whether the tested hollow body (36) corresponds to a defective hollow body (36) or a defect-free hollow body (36) with a first evaluation unit (28a) assigned to the first inspection device (26a), - execution of a first rejection operation (66) for the discharge of a hollow body (36) recognized as defective from the processing line (12) with a first rejection unit (30a) following the first inspection device (26a) in the conveying direction (20), - checking whether the first rejection operation (66) was carried out successfully or unsuccessfully with a first rejection evaluation unit (32a) assigned to the first rejection unit (30a), characterized by - transmitting a first signal (48) indicating a failed rejection attempt from the first rejection evaluation unit (32a) to at least one second rejection unit (30b) following the first rejection unit (30a) in the conveying direction (20) in the case of an unsuccessful first rejection operation (66), and - execution of a second rejection operation (78) for the discharge of the detected defective hollow body (36) from the processing line (12) in the case of receipt of the first signal (48) indicating the rejection failure attempt with the second rejection unit (30b), wherein the second rejection unit (30b) in the conveying direction (20) follows a second inspection device (26b), wherein the second inspection device (26b) in the conveying direction (20) is followed by the first rejection unit (30a) and thus between the first and second rejection units (30a, 30b).

2. The method according to Claim 1, wherein a second rejection evaluation unit (32b) is assigned to the second rejection unit (30b) and the second rejection evaluation unit (32b) is used to test whether the second rejection process (78) was successfully or unsuccessfully executed, and - transmission of a second signal (50) indicating a failed rejection attempt from the second rejection evaluation unit (32b) to at least one third rejection unit (30c) following the second rejection unit (30b) in the conveying direction (20) in the event of an unsuccessful second rejection operation (78) or - stopping of the processing line (12) for the manual removal of the detected defective hollow body (36) from the processing line (12).

3. The method according to Claim 1 or 2, wherein at least one first feature of the hollow body (36) is tested with the first inspection device (26a) and at least one second feature of the hollow body (36) which differs from the first feature with the second inspection device (26b), wherein the method further comprises: - detecting whether the hollow body (36) corresponds to a defective hollow body (36) or a defect-free hollow body (36) with respect to the second feature with a second evaluation unit (28b) assigned to the second inspection device (26b), and - execution of a second rejection process (78) for the removal of a defective hollow body detected with respect to the second feature (36) and with respect to a defective hollow body detected with respect to the first characteristic (36) in the case of receiving the first signal indicating the rejection failure attempt (48).

4. The method according to any one of the preceding claims, wherein a plurality of inspection devices (26a, 26b, 26c), a plurality of rejection units (30a, 30b, 30c), preferably a plurality of processing devices (14), and a control system (47) for controlling at least the plurality of inspection devices (26a, 26b, 26c) and rejection units (30a, 30b, 30c) are arranged along the conveying direction (20), and - with the control system (47), a plurality of or all of the plurality of discharge units (30a, 30b, 30c) following in the conveying direction (20) to one of the plurality of inspection devices (26a, 26b, 26c) are controlled for the execution of a rejection operation (66, 78, 88) of a defective hollow body (36) until a rejection operation (66, 78, 88) of the defective hollow body (36) is successful, wherein, in particular: - a predefined criterion is stored in the control system (47) for a plurality of or each of the processing equipment (14), wherein the criterion indicates which characteristics of the hollow body (36) must be defect-free and / or may be defective for the respective processing device (14), wherein the control system (47) stops the processing line (12) before a defective hollow body (36) which does not meet the criterion of a processing device (14), the corresponding processing device (14).

5. The method according to any one of the preceding claims, wherein in the case of a rejected defective hollow body (36) and / or after detecting the defective hollow body (36) of the position of the defective hollow body (36), at least one assigned processing station of one or a plurality of selected processing equipment (14) is deactivated.

6. The system (10) for the discharge of defective hollow bodies (36), in particular preforms (38) or containers (44), from a processing line (12) for the processing of hollow bodies (36), wherein the system (10) is in particular configured to carry out the method according to one of claims 1 to 5, wherein the system (10) comprises: - a conveyor system (22), in particular with a plurality of conveyors (16, 18), for conveying a plurality of hollow bodies (36) along the processing line (12), - a first inspection device (26a) for testing each hollow body (36), - a first evaluation unit (28a) assigned to the first inspection device (26a) for detecting whether the tested hollow body (36) corresponds to a defective hollow body (36) or a defect-free hollow body (36), - a first rejection unit (30a) following the first inspection device (26a) in the conveying direction (20) for carrying out a first rejection operation (66) for the removal of a hollow body (36) from the processing line (12) which has been identified as defective, - a first rejection evaluation unit (32a) assigned to the first rejection unit (30a) for checking whether the first rejection operation (66) was carried out successfully or unsuccessfully, and - at least one second rejection unit (30b) following the first rejection unit (30a) in the conveying direction (20), characterized in that the first rejection evaluation unit (32a) is configured to send a first signal (48) indicating a failed rejection attempt to the second rejection unit (30b) to the second rejection unit (30b) in the event of an unsuccessful first rejection operation (66) and the second rejection unit (30b) is configured to execute a second rejection operation (78) to reject the detected defective hollow body (36) from the processing line (12) in the event of receiving the first signal (48) indicating the rejection failure attempt, wherein the system (10) has a second inspection device (26b), wherein the second rejection unit (30b) follows the second inspection device (26b) in the conveying direction (20) and the second inspection device (26b) is thus located in the conveying direction (20) after the first rejection unit (30a) and before the second rejection unit (30b).

7. The system (10) according to Claim 6, wherein system (10) comprises a second rejection evaluation unit (32b) assigned to the second rejection unit (30b), for checking whether the second rejection operation (78) was successfully or unsuccessfully executed, - wherein the system (10) comprises a third rejection unit (30c) following the second rejection unit (30b) in the conveying direction (20) and the second rejection evaluation unit (32b) is configured to send a second signal (50) from the second rejection evaluation unit (32b) to the third rejection unit (30c) indicating a failed rejection attempt in the event of an unsuccessful second rejection operation (78), or - the second rejection evaluation unit (32b) is configured to stop the processing line (12) for the manual removal of the defective hollow body (36) detected for rejection from the processing line (12).

8. The system (10) according to any one of the Claims 6 or 7, wherein the first inspection device (26a) is configured, to test at least one first feature of the hollow body (36) and the second inspection device (26b) is configured to test at least one second feature of the hollow body (36) which differs from the first feature, wherein the second evaluation unit (28b) is configured to detect whether the hollow body (36) corresponds to a defective hollow body (36) or a defect-free hollow body (36) with respect to the second feature, and the system (10) is further equipped to carry out a second rejection process (78) for the removal of a defective hollow body (36) detected with respect to the second characteristic and with regard to a defective hollow body (36) detected with regard to the first characteristic in the case of the reception of the first signal (48) from the processing line (12) with the second rejection unit (30b).

9. The system (10) according to any one of the Claims 6 to 8, comprising a plurality of inspection devices (26a, 26b, 26c), which is assigned an evaluation unit (28a, 28b, 28c), wherein each of the evaluation units (28a, 28b, 28c) is configured to control a plurality of or all of the rejection units (30a, 30b, 30c) following the respective inspection device (26a, 26b, 26c) in the conveying direction (20).

10. The system (10) according to any one of the Claims 6 to 9, wherein the system (10) comprises one or a plurality of processing devices (14) which are arranged along the conveyor line (24) and form a processing line (12).