Device and method for warming plastic preforms with spatially resolved temperature detection

Abstract

A device (1) for producing plastic containers, comprising: a warming device (2), the warming device warming plastic preforms (10); and a reshaping device (4), the reshaping device reshaping the heated plastic preforms into plastic containers, wherein the reshaping device (4) is arranged downstream of the warming device in the transport direction of the plastic preforms, and wherein the warming device and / or the reshaping device has at least one regulating device (26, 42), which makes it possible to regulate the warming process and / or the reshaping process according to at least one characteristic of the plastic preforms (10). According to the invention, the at least one regulating device (26, 42) for regulating takes into account at least one variable (G1) that influences the warming process and / or the reshaping process and is variable.

Description

Technical Field

[0001] The invention relates to a device and a method for warming plastic preforms. Background Art

[0002] Such devices and methods have long been known from the prior art. Usually, in a multi-stage process, the plastic preforms are first heated and then reshaped into plastic containers by means of a reshaping device, for example a stretch blow moulding machine. In recent years, there has been an increasing trend towards using recycled materials for the plastic preforms. In particular, the material PET is used here. However, this material leads to the problems described below.

[0003] Firstly, recycled materials more frequently lead to impurities in the material and in the individual plastic preforms, and thus also to increased scrap rates, since these impurities are local defects in the assembly of the material structure and, starting from a certain size, can ultimately also lead to damage during the blow-molding process, such as bottle bursting, which causes disruptions and increased scrap rates.

[0004] Furthermore, fluctuations in the material or material properties, in particular the heat absorption of the plastic preforms, can lead to strong deviations in the heating behavior and thus to strong deviations in the final temperature when leaving the heating path, due in particular to different infrared absorption properties of the plastic preforms heated next to one another in the infrared oven. However, this can also lead to strongly different properties in the subsequent stretch blow molding process and ultimately to completely different container qualities. This can lead to the finished container being unusable (even if the container can still be blow molded) or even to the container bursting already during the production process, which also leads to increased scrap rates. Summary of the invention

[0005] The invention is therefore based on the object of reducing the scrap rate, in particular by recycling materials. This is achieved according to the invention by the subject matter of the independent patent claims. Advantageous embodiments and developments are the subject matter of the dependent claims.

[0006] The device for warming plastic preforms according to the invention comprises a transport device for transporting the plastic preforms along a preset transport path. In addition, the device comprises at least one heating device, which is arranged along the transport path of the plastic preforms so as to warm the plastic preforms during their transport.

[0007] According to the invention, the device comprises a temperature detection device which is suitable and intended for: detecting the temperature of the plastic preforms in a spatially resolved manner.

[0008] The heating device is particularly preferably an infrared oven, i.e. the heating of the plastic preforms is carried out by means of infrared radiation. However, the use of a microwave oven is also conceivable. In a preferred embodiment, the transport device has a surrounding transport mechanism. Advantageously, a plurality of holding devices are provided on the surrounding transport mechanism, which are used to hold the plastic preforms (especially individually), wherein the transport mechanism can be, for example, transport wheels, but can also be a transport chain or a transport belt.

[0009] The transport device preferably transports the plastic preforms along a transport track having a straight section and a curved section. In particular, the temperature detection device is arranged in a section in which the plastic preforms are transported along a curved transport path section. Thus, the transport device can convey the plastic preforms along two straight sections connected to each other by a curved section or curved sections.

[0010] It is therefore proposed to observe the plastic preforms in a heating device or in an oven, in particular in order to obtain information about measures which can lead to the measures described in more detail below, i.e. for example about ejecting the relevant plastic preforms (also called preforms) or intervening in a subsequent blow-molding machine, in order to avoid in any case the explosion of the container during the blow-molding process.

[0011] Furthermore, problems such as too rapid access or filling of the waste bin and thus machine downtime, or filling of perforated containers and thus contamination of the containers, etc., should be avoided. The invention therefore proposes that the plastic preforms are checked spatially resolved, that is to say that not only the temperature of the entire plastic preform is detected, but the plastic preform is checked in a spatially resolved manner, so that the temperature can be associated with specific surface areas of the plastic preform.

[0012] In a preferred embodiment, the temperature detection device has at least one infrared image recording device, which records spatially resolved images of the plastic preforms. It is therefore proposed that the plastic preforms at a specific position, in particular as described in more detail below, are recorded by the infrared image recording device or the infrared camera, i.e. to a certain extent halfway through the infrared furnace. This has the advantage that at least one complete development of the surface of each plastic preform that passes by can be determined and can subsequently be analyzed.

[0013] In this case, in particular, strongly different heating areas of the plastic preforms can be analyzed. In another preferred embodiment, the temperature detection device is arranged in a fixed manner. This means that the plastic preforms are preferably transported past the temperature detection device. Preferably, spatially resolved images of the plastic preforms can be recorded during the transport of the plastic preforms.

[0014] In a further preferred embodiment, the temperature measuring device is arranged along the transport path of the plastic preforms downstream of the first group of heating devices and upstream of the second group of heating devices.

[0015] As described above, the heating device is preferably arranged in a stationary manner and the plastic preforms are transported by the transport device past the heating device. The heating device is preferably arranged along a straight transport section of the plastic preforms, and between the straight transport sections there are curved transport sections and in particular sections in which the transport direction of the plastic preforms is turned or reversed. The temperature detection device is particularly preferably located in this turning area.

[0016] The transport device thus preferably forms a turning zone in which the transport direction of the plastic preforms is reversed. The temperature detection device is preferably arranged in the turning zone. In this design, as described above, the inspection of the plastic preforms is performed to a certain extent halfway.

[0017] However, it is also possible to arrange the image recording device or the temperature detection device at the end of the heating device, that is, downstream of the second heating device. The arrangement in the turning area offers the advantage that retrofitting is possible. This arrangement around the turning area also offers the advantage that no further assemblies or units, such as temperature detection devices, have to be built downstream of the furnace, so that in this way the transport distance of the plastic preforms to the reforming device can also be kept short.

[0018] In a further preferred embodiment, the temperature detection device is suitable and intended to detect the temperature of the plastic preform along a substantially complete circumference and / or length thereof.

[0019] For this purpose, a variety of approaches can be considered. It is therefore possible that the temperature detection device has two image recording devices, which are arranged at two opposite moments of the transport path of the plastic preform and observe the plastic preform from both sides. In addition, it is possible that an image recording device is provided, which records a plurality of images of the plastic preform being transported. In a preferred embodiment, the device comprises a rotating device, which transports the plastic preform by rotating the plastic preform around its own longitudinal direction at least in sections along the transport path. Here, the rotating device can uniformly heat the plastic preform during the heating period.

[0020] In a further preferred embodiment, the device is suitable and intended to also detect the total temperature and / or the total heat of the plastic preforms.

[0021] In another preferred embodiment, the device is suitable for identifying and / or marking a specific plastic preform in response to the detected temperature (spatially resolved temperature or total temperature). Identification and / or marking is understood here in particular as identification for subsequent processing, such as a subsequent remolding process; that is, the machine in particular associates a future processing unit, such as a remolding station, with this specific plastic preform.

[0022] Thus, for example, it can be determined that the total heat of a specific plastic preform deviates from the set temperature. This deviation can be stored, for example in a shift register. Other information, such as the magnitude of the deviation compared to a reference, such as the currently running solution, can also be stored together.

[0023] This information can be forwarded to the control or regulating device so that it can change, for example, specific parameters, i.e., for example, the stretching speed, the pre-blowing duration or the pre-blowing time of a specific plastic preform. In this case, this can be done in a substation-specific manner for a specific reshaping station. In other words, the control and / or regulating device can preferably be adapted to the reshaping process for the plastic preforms.

[0024] However, preferably, a rotation device is also provided, which also rotates the plastic preforms during transport in the area where the image recording device or the temperature detection device is arranged. In this way, a plurality of photographs can be recorded from the same plastic preform.

[0025] Furthermore, a lighting device is particularly preferably provided, which illuminates the plastic preform at least during the image recording. The lighting device is therefore arranged in the region of the inspection device or forms part of the inspection device. The lighting device can be designed as a flashlight or have a flashlight.

[0026] In a further preferred embodiment, the device or the temperature detection device comprises an evaluation device which evaluates the images recorded by the image recording device and determines local temperature fluctuations of the plastic preforms.

[0027] In a preferred embodiment, the temperature detection device is suitable and intended to detect local heating deviations of the plastic preforms and preferably to mark the plastic preforms as defective or contaminated. In this embodiment, it is proposed that the evaluation device detects such heating deviations and marks the corresponding plastic preforms accordingly in response to such deviations (for example in a shift register). In response, the plastic preforms can be discharged, for example at the inlet of the blow molding wheel. In this case, the discharge can take place in particular before the start of the blow molding process.

[0028] Here, it is possible that the evaluation device first combines a plurality of images in order to obtain a complete development of the photograph of the corresponding plastic preform. Within these images, for example, local temperature fluctuations, such as more or less heated areas, can be searched for.

[0029] It is possible here to evaluate the image in the region of pixels or groups of pixels in order in this way to obtain a spatially resolved temperature profile of the plastic preform.

[0030] Preferably, the evaluation device uses artificial intelligence (AI) to evaluate the images recorded from the plastic pre-forms.

[0031] It is thus possible, for example, to provide image processing software which detects local heating deviations. The plastic preforms detected in this way can then be marked as defective and, for example, in a storage device, i.e., a shift register, as being contaminated. It is thus possible to discharge the plastic preforms thus marked at another location, for example, at the inlet of a reshaping device, before they are introduced into the blow-molding process. Alternatively, the blow-molding of such plastic preforms into containers can also be prevented in another way, for example, by shutting off the relevant blow-molding station for the blow-molding process.

[0032] It is also possible not only to detect the fact that a temperature deviation exists, but also to locate its position. For example, the subsequent blow molding process can be adapted to this relevant defect and, for example, the corresponding plastic preform can be blown with different blow molding parameters. In this case, it is possible to also mark the plastic preform in the case of a total thermal deviation, for example by means of a shift register, but together with information about the size of the deviation compared to a reference or (ideal) plastic preform. However, in this case, of course, the reference can also be the solution that is currently running or should be blown later. In this way, as described in more detail below, the temperature profile of the plastic preform can be used to output a prediction about a container to be made in the future.

[0033] The plastic preforms used preferably consist of PET.

[0034] It is possible to pass this information to a control or regulating device or a blow molding control device so that the stretch blow molding parameters, in particular the stretching speed of the stretch rod expanding the plastic preform, the pre-blowing duration or the pre-blowing time, can be intervened in a station-specific manner.

[0035] In this way, the information from the temperature detection device can be used (for example with the aid of an algorithm) to blow-mold bottles as before, which bottles correspond at least to a certain extent to the material distribution of the reference process.

[0036] It is also possible to check the results of the temperature detection device by appropriate online checking techniques after the blow molding process, i.e., for example, wall thickness measurement or bottom inspection. In another preferred embodiment of the invention, these additional measuring techniques can be reflected and used for parameter optimization of the algorithm. In this way, the algorithm or control device described here can be established in a self-learning manner.

[0037] It is therefore possible to compare the results of the temperature detection with subsequent checks, such as container wall thickness checks or bottom checks. Based on these comparisons, further process parameters, such as in particular blow molding parameters, can be adapted in order to obtain a self-improving solution for the device according to the invention in this way.

[0038] In a preferred embodiment, however, the parameters of the algorithms are permanently stored in the control device in a basic embodiment, wherein the algorithms can be executed in a protocol-dependent or protocol-independent manner.

[0039] Here, the influencing parameters for the software or algorithm are selected from the following parameter groups, which include the geometry of the plastic preform, the geometry of the finished container, the infrared absorption of the plastic preform, one or more parameters of the stretch blow molding process (which can also be throttling information about the blow molding process), and a basic scheme is created for these parameter groups.

[0040] In a further preferred embodiment, the apparatus comprises a further inspection device which is arranged in particular downstream of the reforming device for reforming the plastic preforms into plastic containers. The further inspection device can hereby inspect the result of the reforming.

[0041] Thus, the result of the remolding process can be checked by appropriate detection techniques and in particular online inspection techniques (e.g. wall thickness measurement, bottom inspection) after the blow molding process. These additional measurement techniques can be reflected in another embodiment of the concept and used for the parameter optimization of the algorithm. In this way, a self-learning parameter optimization can be performed.

[0042] The present invention also relates to an equipment for manufacturing plastic containers with the aid of an apparatus of the above-mentioned type and a remolding device arranged downstream of the apparatus in the transport direction of the plastic preforms, the remolding device being used to remold the plastic preforms into plastic containers, wherein the remolding device has a plurality of remolding stations for remolding the plastic preforms into plastic containers, and the equipment includes an associating device which associates a specific remolding station with each plastic preform checked by a temperature detection device, and the plastic preforms are remolded in the remolding station.

[0043] In this way, the individual adaptation of the reshaping process can be adapted individually to each plastics material preform and in particular to the inspection results of the plastics material preforms.

[0044] In another preferred embodiment, the device has a control device and / or a regulating device, which controls and in particular regulates the reshaping process in response to the result of the temperature detection and / or the result from the temperature detection device. For example, the parameters of the blow molding process, i.e., for example, the blow molding pressure or the blow molding duration, can be adapted and / or changed.

[0045] The equipment preferably comprises a discharge device, which is suitable for and intended to discharge the plastic preforms from the transport path. Here, in particular, the discharge device is arranged downstream of the warming device. In another preferred embodiment, the discharge device is arranged upstream of the reshaping device.

[0046] The invention further relates to a method for warming plastic preforms, wherein the plastic preforms are transported along a predetermined transport path by means of a transport device and are warmed during the transport of the plastic preforms by means of at least one heating device which is arranged along the transport path of the plastic preforms.

[0047] According to the invention, the temperature detection device detects the temperature of the plastic preforms in a spatially resolved manner. Preferably, the temperature of the plastic preforms is detected during transport of the plastic preforms, ie during their transport movement.

[0048] Based on this temperature detection, at least one value is advantageously output, which is used for controlling or regulating the warming device and / or a reforming device arranged downstream thereof.

[0049] The present invention also relates to an apparatus for manufacturing plastic containers, which comprises: a warming device for warming plastic preforms, wherein the warming device has a transport device for separately transporting the plastic preforms along a preset transport path during the heating of the plastic preforms; and at least one heating device, which warms the plastic preforms while they are transported along the transport path, wherein the warming device preferably also has a first control device, and in particular has a first regulating device for controlling and / or regulating the heating process.

[0050] In addition, the apparatus comprises a reforming device for reforming the heated plastic preforms into plastic containers, wherein the reforming device comprises a plurality of reforming stations for reforming the plastic preforms into plastic containers, wherein the reforming device is arranged downstream of the heating device along the transport direction of the plastic preforms, and wherein the heating device and / or the reforming device comprises at least one regulating device for regulating the heating process and / or the reforming process according to at least one characteristic of the plastic preforms.

[0051] In this case, the reforming device can have a second control device and in particular a second regulating device which controls the regulation of the reforming process as a function of at least one property of the plastic preforms.

[0052] Furthermore, the device preferably has at least one temperature-detecting device, which is arranged in the region of the warming device or between the warming device and the reforming device and which is suitable and intended for detecting the temperature of the plastic preforms.

[0053] According to the invention, at least one of the control device and / or regulating device for regulating takes into account at least one variable which influences the heating process and / or the reshaping process and is variable.

[0054] The property of the plastic preform is advantageously selected from the group of properties comprising the water content, the IR characteristic value and the temperature of the plastic preform.

[0055] These properties can also be characteristic properties of the plastic, which are given, for example, by its material.

[0056] It should be noted that the advantageous embodiments and modifications described with respect to the present invention can also be applied to the above-mentioned invention. Likewise, the advantageous embodiments and modifications proposed with reference to the above-mentioned invention can be applied to the invention mentioned here. In a particularly preferred embodiment, the two inventions can also be combined with each other, which can be advantageous in particular with respect to the adjustment of the reshaping device.

[0057] In the current prior art, in particular the regulation of reshaping equipment, ie for example a blow moulding machine, is a relatively inexpensive process. It is therefore known to measure the temperature of the plastic preforms at the outlet of the warming device and then (re)regulate the warming device itself.

[0058] However, changes and disturbance variables such as plastic preform properties or also environmental conditions are first detected via the temperature change of the plastic preform and then used for regulation. Regulation can be carried out to a certain extent subsequently, for example after determining a deviation of the temperature of the plastic preform from a predetermined temperature.

[0059] Furthermore, it is also known that the user manually intervenes in the heating device or also in the blow molding machine in order to change the corresponding remolding process in this way. Accordingly, systems are also known which control the process, for example, by measuring the wall thickness of the already blow-molded container. Thus, for example, the changed input temperature of the plastic preforms is only taken into account for regulating the machine when the changed input temperature of the plastic preforms has already influenced a change in the output temperature and thus also a change in the container properties. In the process proposed here, the invention is therefore also based on the above-mentioned object: namely, to enable regulation at an early point in time.

[0060] It is therefore proposed that the control already takes into account the variable variables in advance, i.e. "in advance" is understood here to mean that these variables are taken into account before they are influenced in a measurable manner, for example by the temperature heating of the plastic preforms. In this case, the machine can in particular predict how certain variable variables or their changes will influence the production method and in particular the heating process and / or the reforming process or also the finished container.

[0061] Preferably, the variable variable can be selected from the group of variables comprising air humidity, ambient pressure, ambient temperature, properties of the plastic preforms, etc.

[0062] In the context of the present invention, it is therefore proposed that the temperature distribution after the heating process will be under respectively given conditions, or how certain initial conditions or variable variables will influence the temperature distribution.

[0063] Furthermore, other properties, namely for example the wall thickness distribution, can also be predicted (particularly from the above-mentioned variable variables).

[0064] Therefore, within the scope of the present invention, in order to regulate the heating process and / or the remolding process or the blow molding process, changes in the properties of the plastic preforms and / or other influencing variables (these other influencing variables are explained in more detail below) are used directly for the heating and / or blow molding process of the entire machine or for individual plastic preforms, without having to first wait for the results of the process produced by the changing characteristics of the regulating variables.

[0065] Thus, for example, changing properties of the plastic preforms, i.e., different materials, for example, can already be taken into account when adjusting the heating device and / or the reforming device before these properties become apparent during the actual heating process. Both regulating devices, i.e., the regulating device of the heating device and also the regulating device of the blow-molding device, preferably take into account the mentioned variable variables—in particular, take into account the mentioned variable variables in advance. It is possible here that the regulating devices are separately associated with the heating device and the reforming device. However, it is also conceivable that an entire or common regulating device is provided, which regulates both the heating device and the reforming device.

[0066] In another preferred embodiment, the warming device has a plurality of heating devices. Preferably, the heating devices are arranged fixedly relative to the transport path of the plastic preforms. Preferably, the plurality of heating devices can also be controlled and / or adjusted independently of each other.

[0067] It is therefore also proposed that certain variables, i.e., for example, environmental parameters, such as the ambient temperature, or also properties of the plastic preforms, in particular properties based on empirical values, be taken into account in advance and that corresponding modifications be carried out, for example already before or during the plastic preforms enter the heating device or warming device, in order to achieve the desired result for the subsequent reforming process.

[0068] It is therefore proposed that the control of the machine and / or the aforementioned regulating device can generate a prediction of the influence of a change in an input variable in any manner and in particular in a predetermined manner. As explained above, the variable variable is preferably an input variable for a process and / or a treatment method, which then regulates the warming device and / or the reforming device. Preferably, the prediction is generated to compensate for a change in the input variable without causing a significant change in the container properties.

[0069] An example of such an input variable is also the above-mentioned spatially resolved detection of the temperature of the plastic preforms. Based on this spatially resolved temperature, the control device of the warming device and / or the regulating device for the reshaping device can be readjusted so that a satisfactory quality of the produced plastic containers is obtained as a result.

[0070] The control device preferably also takes into account the values ​​output by the temperature detection device. In this way, the warming device and / or the reshaping device can also be adjusted based on these values.

[0071] In a preferred embodiment, the reshaping device has a movable and in particular rotatable carrier. The reshaping stations are preferably arranged on the carrier, wherein the reshaping stations preferably each have a blow mold in which the plastic preforms can be shaped into plastic containers.

[0072] Furthermore, the reshaping station preferably also has a rod-shaped body, in particular a so-called stretching rod, which can be introduced into the interior of the plastic preforms in order to stretch the plastic preforms in the longitudinal direction of the plastic preforms.

[0073] In a further preferred embodiment, the reforming stations each have a loading device which loads the plastic preforms with a flowable medium, in particular a gaseous or liquid medium.

[0074] The regulating device preferably acts on one and preferably a plurality of regulating variables. Here, the regulating variable is selected from the group of variables, which group of variables includes one or more pressures for applying pressure to the plastic preform, the speed of the stretch rod, the magnitude of the pre-blowing pressure, the magnitude of the intermediate blowing pressure, the magnitude of the final blowing pressure, the order of applying pressure, etc.

[0075] The first regulating device for regulating the heating device can also preferably change and / or control at least one and preferably at least a plurality of regulating variables. These variables are selected from a group of variables, which group of variables includes heating power, in particular the heating power of the individual heating devices, the heating power of the heating devices as a function of the height of the plastic preform, etc. The heating device preferably has a plurality of heating radiators, which are particularly preferably arranged one above the other in the direction of the plastic preform to be heated. It is possible here that the individual heating radiators can be controlled individually and thus preferably different regions in the longitudinal direction of the plastic preform are heated differently.

[0076] Another variable to be adjusted can be, for example, the speed of rotation of the plastic preforms about their own axis. The warming device particularly preferably has a rotation device, which rotates the individual plastic preforms relative to their longitudinal direction. It is possible here that each individual plastic preform is rotated individually. However, it is also possible that the plastic preforms can also be rotated uniformly. In this way, it is particularly preferred to also adapt, for example, the speed of rotation of the plastic preforms relative to their longitudinal direction.

[0077] Particularly preferably, the device comprises a processor device which determines a set variable based on the variable variable and / or based on a change in the variable variable, which set variable can be used by at least one of the control devices and preferably both control devices for the control and / or which generates the corresponding control. It is thus possible that the processor device can determine, for example from a variable indicating a changing ambient temperature of the machine, how to adapt the control of the heating device and / or the reshaping device. In this case, the heating device and / or the reshaping device are controlled accordingly.

[0078] By this, variable variables are preferably understood to be changing input variables, i.e., for example, a changed material of the plastic preform or a changed ambient temperature. From these variable variables, the processor device determines a defined variable which indicates or is a measure of how the variable variable influences, for example, how a changed ambient temperature influences the temperature of the plastic preform at the outlet of the warming device. The control device then adapts the controlled variables, i.e., for example, the heating power of the warming device and / or the blowing pressure of the reforming device, based on the defined variables, so that the heating output and / or the blowing pressure are correspondingly the controlled variables.

[0079] The processor device is preferably suitable and intended to determine and / or predict the influence of the variable variable and / or the change of the variable variable on the heating process and / or the reshaping process, and on this basis, influence the regulation and / or the regulation.

[0080] In a preferred embodiment, the device and / or the processor device determines the specified variables and / or the regulating variables based on the model. The control and / or regulation thereby preferably implements a model which determines the correlation between the influencing variables and the results or the container properties and / or the specified variables. The model can be permanently stored in the machine control. However, it can also be parameterized by the operator or by measurements of the device itself and / or the container properties.

[0081] In a preferred embodiment, the device therefore also has a testing device which tests the finished or blow-molded containers. In this case, for example, the containers can be tested with respect to the wall thickness of their walls. In addition, local differences in wall thickness can also be determined. The results of this testing are preferably also taken into account when adjusting the warming device and / or the reshaping device.

[0082] The device preferably comprises a memory device in which the defined variables and deviations of the input variables as well as the variables resulting from the inspection of the finished containers and / or the heated plastic preforms are recorded. In this way, a plurality of value tuples can be determined.

[0083] For example, when there are specific environmental parameters, such as ambient temperature, and plastic preforms of a specific material are used here, it can be determined and stored: what wall thickness and what temperature of the heated plastic preforms are obtained. In addition, a plurality of such values ​​can be entered in the storage device.

[0084] In this way, it is possible that the machine can learn itself to a certain extent and store a plurality of such relationships in a memory device. If, in future operation, environmental properties, such as the ambient temperature, change, this change can be taken into account and readjustment can be performed accordingly based on the stored empirical values ​​in order to keep the container quality constant.

[0085] It is therefore particularly proposed that within the scope of the regulation of the remolding device and / or the heating device, not only the result is taken into account as a regulating variable, as is customary, but also a changing input variable. For example, for a plastic preform of a specific material, a plurality of ambient temperatures and, for example, also a plurality of thicknesses of the wall of the plastic preform are stored. In this case, for example, an expected value can be associated with a specific material, i.e. how to heat the plastic preform, in a database or a query table or with the aid of a regression model for a specific temperature and a specific wall thickness. This expected value can be transmitted to the regulating device of the blow molding machine and the heating device, and the regulating device can control or modify the process accordingly (in a manner corresponding to the case of the measured result).

[0086] In a preferred embodiment, the variables influencing the heating process and / or the remolding process are selected from a group of variables, which group of variables includes the physical properties of the plastic preforms to be processed, such as in particular their material, their dimensions, wall thickness, etc.; environmental conditions such as in particular ambient temperature, ambient pressure or ambient air humidity, etc.; machine conditions of the equipment, etc.

[0087] In another preferred embodiment, at least the second control device enables individual regulation for each plastic preform. It should be taken into account that, as described above, the reshaping device has a plurality of reshaping stations, each of which is used to produce a container. However, this also allows the blow-molding process of each individual plastic preform to be controlled individually.

[0088] In a preferred embodiment, the device comprises an associating device which associates a specific reshaping station with each plastic preform fed to the warming device, the specific reshaping station reshaping the plastic preform. In this way, the process can be individually adapted to the respective plastic preform.

[0089] It should be noted that the above-mentioned design of the temperature of the plastic preforms detected locally in a spatially resolved manner is a feasible design of the invention described here. Therefore, the value of the check is already supplied to the adjustment part of the heating device or also the subsequent blow molding machine before its final implementation.

[0090] In a further preferred embodiment, the device comprises at least one detection device for detecting a variable variable. Thus, for example, a detection device can be provided in or during the warming device, which detects, for example, the wall thickness of the plastic preform or its material. These values ​​can be used in advance as variable input variables for the regulation.

[0091] In a further preferred embodiment, the device comprises a detection device which is suitable and intended to detect the absorption behavior of the plastic preforms. The detection device can be arranged in an inlet area in which the plastic preforms enter the warming device or also along the warming route. A plurality of such detection devices can also be provided.

[0092] In a further advantageous embodiment, the device comprises an adaptation device and / or an additional temperature control device and in particular an additional warming device in order to change and in particular increase the heating of individual plastic preforms or groups of plastic preforms (in particular individually). In this way, an individual setting of the heating power and / or the heating time of the plastic preforms can be carried out. In this case, the adaptation can be carried out, for example, in response to the (in particular measured) absorption behavior and / or the (in particular measured) temperature.

[0093] Therefore, the heating power can be adapted to individual plastic preforms or (especially groups of plastic preforms following each other) and in particular the heating power can be increased. Here, the adaption device can be configured so that additional heating of the entire plastic preform is performed, but it is also possible to perform such adaptation in specific local areas of the plastic preform.

[0094] Preferably, the adapter device is arranged along the transport path of the plastic preforms, for example in the inlet or along the transport route.

[0095] In an advantageous embodiment, the adapter device has at least one radiation device and in particular at least one laser. The radiation device can locally additionally heat individual regions of the plastic preforms, or alternatively also heat the individual plastic preforms as a whole. Additional heating by means of microwaves is also possible.

[0096] However, (individual) cooling of the individual plastic preforms is also conceivable, for example by subjecting them to cooling air (or for additional warming by subjecting them to hot air).

[0097] The present invention also relates to a method for manufacturing plastic containers, wherein a heating device heats plastic preforms, and wherein a transport device of the heating device transports the plastic preforms separately along a preset transport path during the heating of the plastic preforms, and at least one (especially fixedly arranged) heating device heats the plastic preforms during the transport of the plastic preforms along the transport path, and wherein a reshaping device reshapes the heated plastic preforms into plastic containers, wherein the reshaping device has a plurality of reshaping stations for shaping the plastic preforms into plastic containers, wherein the reshaping device is arranged downstream of the heating device in the transport device for the plastic preforms, and wherein at least one regulating device of the heating device and / or the reshaping device controls and / or regulates the heating process and / or the reshaping process according to at least one characteristic of the plastic preform (10).

[0098] In this case, the control device and / or regulating device of the reforming device can regulate the reforming process as a function of at least one characterizing property of the plastic preforms.

[0099] Furthermore, preferably at least one temperature detection device in the region of the warming device or between the warming device and the reforming device detects the temperature of the plastic preforms.

[0100] The first control and / or regulating device of the warming device preferably controls and / or regulates the warming process at least temporarily.

[0101] According to the invention, at least one of the regulating devices for regulating anticipates at least one variable that influences the warming process and / or the reshaping process and is variable, and also performs regulation based on this variable. Preferably, both regulating devices anticipate variable variables.

[0102] Therefore, the method also proposes that, in contrast to previous controls, input variables of the process are also taken into account. Preferably, it is determined here from the input variables or variable variables how they influence the heating process and / or the reforming process (especially empirically).

[0103] In a preferred method, the regulation is performed based on a model which predicts the effect of a variable variable on the heating process and / or the reshaping process, for example, a changing material may result in a change in infrared absorption, and this may be predicted, for example, based on previously known data or based on learned experience and / or empirical values.

[0104] Preferably, the model can be parameterized. It is possible here that the model can be parameterized by a user or by the machine itself, for example in a self-learning manner. However, it is also possible that the model is stored permanently.

[0105] In a further advantageous method, the heating of individual preforms or individual groups of preforms is adapted and in particular increased.

[0106] The adaptation is preferably carried out by at least one laser, in particular as a function of the absorption behavior of the plastic preforms. Preferably, the adaptation is carried out during transport, such as in particular during movement of the plastic preforms.

[0107] The absorption behavior of the plastic preforms is preferably characterized. BRIEF DESCRIPTION OF THE DRAWINGS

[0108] Further advantages and embodiments can be seen from the attached drawings. The drawings show:

[0109] Figure 1 A schematic diagram is shown of an apparatus for producing containers according to the invention. DETAILED DESCRIPTION

[0110] Figure 1 A schematic diagram of a device for producing containers according to the invention is shown. Here, the plastic preforms 10 are first separated and fed to a warming device, which is provided with the reference numeral 2 as a whole. The warming device 2 has a transport device 22. The transport device is designed as a circulating transport chain, on which a plurality of holding devices 28 are arranged, each holding a plastic preform. Figure 1 It can be seen that the plastic preforms are also rotated here relative to their longitudinal axis. A plurality of heating devices 24a, 24b are arranged stationary along the transport path P. The plastic preforms 10 are guided past the holding device and are heated in the process.

[0111] Reference numeral 6 denotes an inspection device which is arranged in the deflection region of the transport path P and in particular in a region where no heating device is provided. As already mentioned above, the inspection device records spatially resolved images of the plastic preforms and in particular of their temperature behavior.

[0112] Reference numeral 12 denotes a further temperature detection device which detects the overall temperature or the complete temperature of the heated plastic preforms. The temperature value can also be used to control and / or regulate the heating device or the subsequent reshaping device 4.

[0113] Reference numeral 26 denotes a regulating device for regulating the warming device 2. A transport device 41 and a reshaping device 4 are connected to the warming device 2. The reshaping device 4 has a plurality of reshaping stations 44 arranged on a carrier 46. Reference numeral 42 denotes a regulating device for regulating the reshaping device.

[0114] Reference numeral 14 roughly schematically designates a processor device which, taking into account at least one input variable, in particular the above-mentioned variable variables, determines a defined variable which predicts a specific behavior or a specific property of the plastic preform or the finished container.

[0115] The applicant reserves the right to claim the features disclosed in the present application documents as the essence of the present invention, as long as the features are novel with respect to the prior art, either individually or in combination. In addition, it should be noted that features that can be advantageous in themselves are also described in the various figures. It should be immediately recognized by those skilled in the art that specific features described in the figures can also be advantageous without adopting other features in the figures. In addition, those skilled in the art recognize that advantages can also be obtained by combining more features shown in individual or different figures.

[0116] Reference numerals list

[0117] 1 Equipment

[0118] 2 Heating device

[0119] 10 Plastic preforms

[0120] 12 Temperature detection device

[0121] 14 Processor device

[0122] 22 Transport device

[0123] 24a, 24b Heating device

[0124] 26 Heating device adjustment device

[0125] 28 Holding device

[0126] 41 Transport device

[0127] 42 Adjustment device (of reshaping device)

[0128] 44 Reshaping Station

[0129] P Transportation Path

Claims

1. A device (1) for manufacturing plastic containers, comprising: A warming device (2) for warming plastic preforms (10), wherein the warming device has a transport device (22) for separately transporting the plastic preforms (10) along a predefined transport path (P) during the warming of the plastic preforms, and comprises at least one heating device (24a, 24b) for warming the plastic preforms during their transport along the transport path; and a reshaping device (4), wherein the reshaping device reshapes the heated plastic preforms into plastic containers, wherein the reshaping device (4) has a plurality of reshaping stations (44) for reshaping the plastic preforms into plastic containers, and wherein the reshaping device (4) is arranged downstream of the warming device in the transport direction of the plastic preforms, and wherein the warming device and / or the reshaping device has at least one regulating device (26, 42), which makes it possible to regulate the heating process and / or the reshaping process according to at least one characteristic of the plastic preforms (10), and wherein the device also includes at least one temperature detection device (12), which is arranged in the area of ​​the warming device (2) or between the warming device (2) and the reshaping device (4), and which is suitable for and intended to detect the temperature of the plastic preforms (10), It is characterized in that At least one of the regulating devices (26, 42) for regulating takes into account at least one variable that influences the heating process and / or the reshaping process and is variable, The variable variables considered in advance are understood here to mean that these variables are considered before they are influenced in a measurable way, and the machine is able to predict how certain variable variables or changes thereof will influence the heating process and / or the reshaping process or also the finished container, and further, wherein To regulate the heating and / or reshaping process, changes in the properties of the plastic preforms are used directly for the heating and / or blowing process of the entire machine or of individual plastic preforms without first having to wait for the results of the process by changing the properties of the regulating variables.

2. The device (1) according to claim 1, It is characterized in that The device comprises a processor device (14) which determines a setpoint variable (B1) based on a variable variable and / or based on a change in the variable variable, which setpoint variable can be used by at least one of the regulating devices (26, 42) for regulation.

3. The device (1) according to claim 2, It is characterized in that The processor device (14) is suitable for determining the influence of the change of the variable variable on the heating process and / or the reshaping process.

4. The device (1) according to claim 2, It is characterized in that The device (1) and / or the processor device (14) determines the predetermined variable based on a model.

5. The device (1) according to claim 1 It is characterized in that The variables influencing the warming process and / or the reshaping process are selected from the group of variables comprising physical properties of the plastic preforms to be processed, environmental conditions, and machine states of the installation.

6. The device (1) according to claim 1, It is characterized in that At least one of the regulating devices (26, 42) enables individual regulation of the treatment of each plastic preform.

7. The device (1) according to claim 1, It is characterized in that The device (1) comprises an association device which associates with each plastic preform conveyed to the warming device (2) a specific reshaping station which reshapes the plastic preform.

8. The device (1) according to claim 1, It is characterized in that The device (1) comprises at least one detection device for detecting the changeable variable.

9. The device (1) according to claim 1, It is characterized in that The device (1) comprises an adaptation device in order to vary the heating of individual plastic preforms or groups of plastic preforms.

10. The device (1) according to claim 9, It is characterized in that The adapter device has at least one radiating device.

11. A method for manufacturing plastic containers, wherein a warming device (2) warms plastic preforms (10), wherein a transport device (22) of the warming device transports the plastic preforms (10) separately along a preset transport path (P) during the warming of the plastic preforms, and at least one heating device (24a, 24b) warms the plastic preforms during the transport of the plastic preforms along the transport path, and wherein a reshaping device (4) reshapes the heated plastic preforms into plastic containers, wherein the reshaping device (4) has a A plurality of reshaping stations (44) for forming plastic containers, wherein the reshaping device (4) is arranged downstream of the heating device in the transport direction of the plastic preforms, and wherein at least one regulating device (26, 42) of the heating device and / or the reshaping device controls and / or regulates the heating process and / or the reshaping process as a function of at least one property of the plastic preforms (10), and wherein at least one temperature detection device (12) in the area of ​​the heating device (2) or between the heating device (2) and the reshaping device (4) detects the temperature of the plastic preforms (10), It is characterized in that At least one of the regulating devices (26, 42) for regulating takes into account at least one variable (G1) that influences the heating process and / or the reshaping process and is variable, and also performs the regulation based on the variable, The variable variables considered in advance are understood here to mean that these variables are considered before they are influenced in a measurable way, and the machine is able to predict how certain variable variables or changes thereof will influence the heating process and / or the reshaping process or also the finished container, and further, wherein To regulate the heating and / or reshaping process, changes in the properties of the plastic preforms are used directly for the heating and / or blowing process of the entire machine or of individual plastic preforms without first having to wait for the results of the process by changing the properties of the regulating variables.

12. The method according to claim 11, It is characterized in that The regulation is carried out on the basis of a model which, on the basis of variable variables, predicts the influence of the variable variables on the heating process and / or the reshaping process.

13. The method according to claim 12, It is characterized in that The model can be parameterized.

14. The method according to claim 11, It is characterized in that The heating is adapted to the individual preforms or groups of preforms.

Images