Stretch blow molding machine with pressure device

Abstract

Device (1) for treating plastic containers with a blow molding device (2) which expands preforms into containers (10), wherein this blow molding device has a plurality of blow molding stations (4) in which preforms can each be expanded into containers (10), with a transport device (8) arranged downstream of the blow molding device (2), characterized in that at least one pressure device (12) is provided which imprints the containers (10) with at least one design during transport with the transport device (8), wherein the transport device (8) receives the containers (10) expanded by the blow molding stations (4) and transports them singly, and wherein the transport device (8) is designed in the form of a discharge star, wherein the pressure device (12) is arranged on this discharge star, which is designed and provided for imprinting the containers.

Description

The invention relates to a device for treating plastic containers, and more precisely, a device for expanding plastic preforms into plastic containers. Such devices have been known in the art for a long time. Typically, these devices have a multitude of blow molds within which plastic preforms are expanded into plastic containers, for example, by means of compressed air. Downstream of these blow molds, there are usually further systems for treating the containers, such as disinfection systems, filling systems, cappers, and the like. Furthermore, such systems typically also include labeling machines that apply labels to the manufactured containers. Often, it is also desirable to individually identify containers during production. DE 2005 041 221 A1 discloses a device and a method for producing labels with RFID transponders. RFID systems comprise a reading device and an RFID transponder (an RFID tag). The reading device typically includes a high-frequency transmitter and receiver and a coupling element, such as a coil or antenna, for communication with the transponder. In many applications, the reading device also supplies the transponder with energy by emitting a high-frequency electromagnetic field, which induces a voltage in the transponder's antenna coil.From WO 2008 / 031558A1, a valid wiring configuration is known. Compared to identification systems such as barcodes, RFID transponders have the advantages of being reprogrammable, offering high data storage capacity and reliable readability. Accordingly, DE 10 2005 041 221 proposes integrating an RFID transponder into the label during its production. This approach allows for the identification of the container as soon as the transponder is attached. However, in some cases, it is desirable to enable container identification at an earlier stage. The present invention is therefore based on the objective of providing a device for treating plastic containers which allows for early individualization or identification of the containers. This is achieved according to the invention by a device according to claim 1 and a method according to claim 13. Advantageous embodiments and further developments are the subject of the dependent claims. An inventive device for treating plastic containers comprises a blow molding unit that expands preforms into containers. This blow molding unit has a plurality of blow molding stations, in each of which preforms can be expanded into containers. Furthermore, a transport device is provided that receives the containers expanded by the blow molding stations and transports them individually. According to the invention, a printing device is provided that imprints the containers with at least one design during transport by the transport device. In the following, the term "printing equipment" refers not only to printing equipment that physically acts on and changes the material to be printed, but also, in particular, to equipment that applies flowable and especially liquid materials to the containers. The inventive method therefore makes it possible to individualize or identify the container directly after its manufacture. Preferably, the imprint is not applied together with a label in a labeling machine, but immediately after the container is produced, particularly in an exit area of ​​the blow molding unit. Preferably, the printing device comprises at least one printing element that applies, and particularly preferably sprays, an electrically conductive substance onto the containers. A printing device of the type of an inkjet printer printhead is preferably used. However, the term "ink" is used here in a very general sense and is not limited to water- or oil-based inks, etc., but also includes liquids or flowable media containing electrically conductive particles such as stainless steel shavings, copper particles, or the like. Preferably, the printing device comprises at least one printing element that applies an electrically conductive substance to the containers. This electrically conductive substance is understood to be a conductive or semiconducting material. Therefore, the term "ink" as used above also includes any electrically conductive liquid suitable for printing, for example, using conventional printheads. In particular, the term "ink" here also encompasses polymers that can be printed in ultra-thin layers with high precision and can be processed similarly to ink. In a further advantageous embodiment, the printing device is arranged in a stationary position, meaning that the aforementioned transport device or the containers move relative to the stationary printing device. This allows the imprint to be generated while the containers are moving. Preferably, the imprint will be a smart label or components thereof. However, other imprints, such as, but not exclusively, colored images, would also be conceivable. Such colored images could also be used to identify the containers. This proposes that a printing device be provided on the transport system, which could, for example, be designed as a transfer star, enabling the direct printing of a smart label (especially with conductive ink or paint) onto the containers. The smart labels can be printed on the bottom, at the mouth or shoulder, or in a central area of ​​the containers. This intelligent printing process enables the regulation and control of the subsequent material flow within a downstream production line. This control can be extended all the way to the shipping warehouse. The printing on these smart labels thus incorporates printable electronics that allow for the writing and reading of information, enabling communication with control units, particularly those located downstream of the blow molding unit, throughout the entire filling and packaging line. This communication is therefore possible not only during container manufacturing but also during filling, labeling, packaging, palletizing, in a finished goods warehouse, and even during truck transport. In another advantageous embodiment, the printing device is designed to apply a smart label to the containers. Advantageously, the printing device has a plurality of nozzles for applying the print. In addition to the printing device that prints an intelligent smart label onto the containers, it would also be possible to arrange further printheads on the transport device, which, for example, could apply a colored image to the container using multicolor printing. The aforementioned plurality of nozzles for applying the print makes it particularly advantageous, for example, to create an antenna or the like for the intelligent printing process. Preferably, a drying device for the print is provided downstream of the printing device. This drying device can be a near-infrared drying device for drying printed ink. Alternatively, a curing device, such as an ultraviolet curing device, can be provided for curing ink as well as any connections between a microchip and the other components of the smart label. This latter device can be used to connect a microchip to the container and bring it into electrical contact with the antenna of an RFID transponder, for example, by bonding it to the substrate or the surface of the container. In this context, reference is made to the above-mentioned DE 10 2005 041 211 A1, the disclosure content of which is hereby also made fully the subject of the present application by reference. In a further advantageous embodiment, the printing device comprises a plurality of printing elements arranged one after the other in the transport direction of the containers. In this way, a substrate can first be applied to the containers, followed by a semiconductor coating, then an insulator, and finally electrodes or an antenna. Preferably, at least one printing element applies a carrier material to the container, which as a whole serves as a carrier for a transponder. Advantageously, the support material contains a substance selected from a group of substances including polyalkylthiophenes (PAT), polyfluorenes (PF), polyphenylenevinylene (PPV), polystyrene (PS), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), combinations thereof, and the like. Specifically, particular support materials such as the aforementioned PAT, PF, or PPV are preferably used in combination with PS, PMMA, or PET, the latter serving as the insulator or support substrate. Furthermore, the transport device features rotating bodies that cause the containers to rotate around their longitudinal axis. This means that the containers are not only moved along, for example, a circular path by the transport device itself, but also rotated around their own axis. In this way, it is possible to print on the containers over a larger circumferential angle. This method would also allow for complete printing on the containers. Furthermore, a camera is preferably provided to monitor the containers during transport with the transport device. This allows the printed design to be checked and its functionality to be tested visually. For example, it is possible to check the antenna's functionality. Preferably, the camera is arranged downstream of the printing device. The present invention further relates to a method for treating containers. In a first process step, preforms are introduced into a blow molding device which has a plurality of blow molding stations, each of which expands a preform into a container. In a further step, the preforms are transported by the blow molding device, whereby the preforms are expanded into containers during transport. Finally, the expanded containers are transferred to a transport device located downstream of the blow molding device, which transports the containers individually. According to the invention, the containers are individually printed during transport with the transport device using a printing device. The inventive method also proposes printing the containers essentially immediately after their manufacture or expansion. Printing is understood to include, in particular, spraying flowable and especially liquid materials onto the container. Preferably, the printing device applies a flowable material to the containers. It is therefore proposed to use a printing device similar to an inkjet printer for printing on the containers. Advantageously, the printing device applies an electrically conductive material to the containers, and this electrically conductive material is advantageously used to apply smart labels to the containers. In another preferred method, the printing device prints an antenna device onto the containers, wherein this antenna device is also preferably used as an antenna for a smart label. In another advantageous method, the printing device prints several layers one after the other onto the containers. Further advantages and embodiments can be seen from the attached drawings: This document shows: Fig. 1 A representation of a device according to the invention; Fig. 2 A block diagram illustrating a system with a device according to the invention; Figs. 3a - 3c Illustrations illustrating printing devices according to the invention; Fig. 4 A further illustration illustrating a printing method; Fig. 5 A schematic representation illustrating a printing device; Fig. 6 A further schematic representation illustrating the invention; and Fig. 7 A side view of the representation shown in Fig. 6. Fig. 1 shows a schematic representation of a device according to the invention. Reference numeral 32 refers to a sorting device which positions preforms in a desired orientation in order to subsequently feed them to a heating device 34. The containers 10 are fed to the heating device 34 by means of a single-feed wheel 3, whereby the containers are separated from this single-feed wheel or transported by their respective gripping elements. After the heating process in the heating device 34, the preforms enter a stretch blow molding machine 2 via an infeed star wheel 6. In this stretch blow molding machine 2, the preforms are expanded into plastic containers. For this purpose, the stretch blow molding machine 2 has a plurality of blowing stations 4, in each of which the preforms are expanded. A transport device 8 in the form of a star-shaped discharge unit is connected to this stretch blow molding machine 2. A printing device 12 is arranged on this star-shaped discharge unit, which imprints the containers. Here, the term printing device is not only understood to mean a printing device in the narrow sense, but any device that applies symbols or legible elements to a template. More precisely, the printing device 12 is preferably an inkjet printing device, which generates the print by spraying flowable substances onto the containers 10. A transport device 9, such as a conveyor belt, is connected to the discharge star 8. This means that the containers 10 are no longer guided individually downstream of the discharge star 8, but rather in rows. However, since the containers are printed with a design, they can be individually identified at a later time via this design. Preferably, an image acquisition device 14, such as a camera, is also provided on the printing device 12. This device checks the printed designs, for example, in the case of a smart label, whether the geometric shape is correct. Preferably, this image acquisition device 14 is connected to a control device in order to report any errors to this control device. It would also be possible to reject containers 10 with defective printed designs. Fig. 2 shows a block diagram of a system with a device 1 according to the invention. The arrows refer to the transport direction of the containers through the system. After the containers are produced in the blow molding unit 2, they are individualized by the printing unit 12 according to the invention. Reference numeral 40 refers to control and regulating devices that are capable of reading and writing generated smart labels. Downstream of the blowing device 2, a filling device 42 is arranged, which fills the containers with a beverage. This filling device 42 is designed such that it has several filling elements 43 which can fill the containers with different beverages. Depending on the incoming bottle, it is therefore possible to select which beverage the containers are filled with. In this way, the control device is suitable for identifying the respective container and, in response to this identification, initiating filling with a specific beverage. Simultaneously, the control unit 40 can also write information to the smart label, such as which product was filled, information about a filling date, and the like. A disinfection unit 44 and / or a cold water rinser is connected to the filling unit 42. The reference numeral 46 refers to a labeling unit that has several different labeling elements 47, which are capable of applying different labels to the containers. Accordingly, a control unit is also provided here, which reads a smart label to determine which label is to be applied to the container. Reference numeral 46 indicates a closure device, at whose inlet a corresponding control and regulating device 40 may also be provided, which decides with which closure a particular container is to be fitted. Reference numeral 48 designates a shrink tunnel, which is also equipped with a control and regulating device 40 to ensure that certain containers are fitted with the packaging intended for them. Reference numeral 49 refers to a further transport device. Accordingly, a packaging system 52 can use the information read from the smart label to decide which transport path 53 the containers should be directed to. However, other system components could also be conceivable that can be controlled by means of appropriate control and regulating devices 40, such as palletizing systems, depalletizing systems, conveyor belts, and the like. As mentioned above, the smart labels are produced by printing their individual components directly onto the containers using an inkjet printer. Special printing inks, primarily organic polymers, are used for this purpose. These inks are electrically conductive or semiconducting. The ink can be applied to the containers in a mist-like manner or in fine lines as an electrically conductive substance. Nanosilver-containing substances can be cited as an example of an electrically conductive substance. Preferably, the particles in the inks have a structural size of less than 30 µm. Figures 3a-3c show further embodiments of the arrangement of a printing device 12. These printing devices are suitable not only for printing containers with smart labels but are also generally suitable for printing on bottles, for example, instead of using labels. Reference numeral 10 refers to a bottle that is transported by the aforementioned transport device 8. A printing device 12 prints on the outer wall of this bottle, and in the embodiment shown in Figure 3a, the printing device 12 is adjustable along the double arrow P, i.e., in its height, in order to print the entire area of ​​the outer wall of the container. A printing unit could also be located at a different point in the system, for example, after a filler. It would also be possible for one or more printing units to replace a labeling unit. Fig. 3b shows an application in which bottles with a rounded or bulbous body can be printed. Here, too, it is possible to design the printing device 12 at a height that allows the entire body area of ​​the container 10 to be printed. In a further embodiment, it would also be possible to make individual printing elements 12a, 12b, and 12c slidable relative to each other, so that, for example, in Fig. 3b, the uppermost and lower segments 12a can be moved towards the container 10 in the direction of arrow A, in order to achieve equal or similar distances between the printing elements and the container. Fig. 3c shows a further embodiment of a printing device 12 according to the invention. In this case, it would be possible to tilt the printing device as shown in order to print on inclined outer walls of the containers as well. It would also be possible to combine the embodiments shown in Figs. 3a - 3c in order to produce prints on a wide variety of containers 10. Fig. 4 shows a further embodiment of a printing device 12 according to the invention. In addition to rotating the transport device along arrow P2, it is also possible to rotate the containers themselves about their own axis (arrow P1). In this way, a larger circumferential area of ​​the respective containers can be printed with the printing device 12, since the relative speed between the outer wall of the container and the printing device 12 increases. It would also be possible to rotate the containers in Fig. 4 in the opposite direction to reduce the relative speed between the outer wall of the containers 10 and the printing device 12. This could be particularly interesting for high-speed systems or in cases where a very high-quality print is required. Furthermore, it would also be possible to arrange several identical printing devices one after the other in the transport direction of the containers in order to increase the throughput. In this case, only every nth container would be printed by a specific printing device, where n is the number of printing devices. Fig. 5 shows a schematic representation of a printing device 12. The arrow P3 symbolizes the direction of movement of the containers. This printing device 12 has a plurality of printing elements 16a, 16b, 16c. In a preferred embodiment, each of these printing elements 16a, 16b, 16c has a plurality of nozzles, for example 512 nozzles, each of which dispenses a printing medium. The printing device shown in Fig. 5 would be suitable, for example, for applying a four-color print to the containers, with the two upper rows I printing the first color, the two rows II printing the next color, the two rows III printing the third color, and finally the two rows IV printing the fourth color. Thus, the printing elements 16a, 16b, and 16c are arranged one behind the other in the transport direction P3, so that the colors are applied sequentially. It can be seen that the individual printing elements 16a, 16b, and 16c of row I are offset from one another. It should be noted that the individual printing elements have side margins. If the individual printing elements 16a, 16b, and 16c were arranged in a row, an unprinted area would occur in the transition between them. By offsetting the printing elements along arrow P3, this offset can be compensated for, thus creating a continuous print. More precisely, this ensures that the individual nozzles of the printing elements 16a, 16b, and 16c are directly adjacent to one another. A drying unit 24, which may include a UV lamp, is connected to the printing unit 12. Fig. 6 shows a further embodiment of a transport device according to the invention. Here, the container 10 is guided eccentrically relative to the transport device 8 by means of a rotary table 28 and a guide device 26, in order to ensure that a distance d between the pressure device 12 and the outer wall of the container is essentially constant within a certain range. The entire rotary table 28 moves on a circular path (see Fig. 4). By skillfully adjusting the eccentric rotation with the guide device 26 to the transport speed of the transport device 8, the aforementioned distance d can be kept essentially constant. If the container 10 rotates around its own axis again, this area can be enlarged at essentially constant distances. Fig. 7 shows a side view of the representation shown in Fig. 6. It can be seen that a bottle tray 28, which is part of the transport device 8, is rotatable about its axis of rotation D, and the container 10 itself is rotated about its own axis with respect to the axis L. It is possible for the rotation about the axis D and the rotation about the axis L to occur in the opposite direction. Depending on the application, however, it would also be possible for the rotations about the axes L and D to occur in the same direction, or for the container not to be rotated about its own longitudinal axis L. All features disclosed in the application documents are claimed to be essential to the invention, provided that they are novel individually or in combination compared to the prior art.

Claims

Device (1) for treating plastic containers with a blow molding device (2) which expands preforms into containers (10), wherein this blow molding device has a plurality of blow molding stations (4) in which preforms can each be expanded into containers (10), with a transport device (8) arranged downstream of the blow molding device (2), characterized in that at least one pressure device (12) is provided which imprints the containers (10) with at least one design during transport with the transport device (8), wherein the transport device (8) receives the containers (10) expanded by the blow molding stations (4) and transports them singly, and wherein the transport device (8) is designed in the form of a discharge star, wherein the pressure device (12) is arranged on this discharge star, which is designed and provided for imprinting the containers. Device (1) according to claim 1, wherein the pressure device (12) has at least one pressure element (16). Device (1) according to at least one of the preceding claims, wherein the pressure device (12) is arranged in a stationary position. Device (1) according to at least one of the preceding claims, wherein the printing device (12) has a plurality of nozzles for applying the print. Device (1) according to at least one of the preceding claims, wherein a drying device (24) and / or a curing device for the print is provided downstream with respect to the printing device (12), and wherein the curing device preferably comprises an ultraviolet curing device for curing ink. Device (1) according to at least one of the preceding claims, wherein the pressure device (12) has a plurality of pressure elements (16, 18, 20). Device (1) according to claim 6, wherein the printing elements (16, 18, 20) are arranged one behind the other in the transport direction of the containers (10), wherein at least one printing element (16, 18, 20) is a printhead which applies ink to the container (10) according to the inkjet principle. Device (1) according to at least one of the preceding claims, characterized in that at least one pressure element (16, 18, 20) is displaceable in the longitudinal direction (L) of the containers. Device (1) according to at least one of the preceding claims, characterized in that the transport device (8) has rotatable bodies which cause the containers (10) to rotate about their longitudinal axis (L) and wherein the containers are not only moved along a circular path by the transport device itself but are also rotated about their own axis. Device (1) according to at least one of the preceding claims, wherein further printheads are arranged on the transport device which apply a multicolor print to the container and wherein the further printheads apply a colored image to the container via the multicolor print. Device (1) according to at least one of the preceding claims, wherein an inlet star (6) is arranged upstream of the blowing device (2) and a heating device (34) is arranged upstream of the inlet star (6) and a single-stroke wheel (3) is arranged upstream of the heating device (34), wherein the preforms are separated from this single-stroke wheel or transported on the gripping elements assigned to them and a sorting device (32) is arranged upstream of the single-stroke wheel, which brings preforms into a desired orientation. Device (1) according to at least one of the preceding claims, wherein an image acquisition device (14), in particular a camera, is arranged on the printing device (12), which checks the imprints and the image acquisition device (14) is connected to a control device in order to report any errors to this control device. Device (1) according to at least one of the preceding claims, wherein a filling device (42) is arranged downstream of the blowing device (2), which fills the containers (10) with a beverage. Device (1) according to at least one of the preceding claims, wherein one or more printing devices are suitable to replace a labeling device. Device (1) according to at least one of the preceding claims, wherein the printing device (12) is designed to be tiltable in order to print on inclined outer walls of the containers (10). Device (1) according to at least one of the preceding claims, wherein several similar pressure devices (12) are arranged one behind the other in the transport direction of the containers (10). Device (1) according to claim 16, wherein only every nth container is printed by a specific printing device, where n is the number of printing devices. Device (1) according to at least one of the preceding claims, wherein the transport device comprises a rotatable turntable (28) for receiving the container (10). Device (1) according to claim 18, wherein the entire turntable (28) moves itself on a circular path.

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