DE102019128501A1 - Manufacturing process for plastic container and blow molding machine - Google Patents

Abstract

Manufacturing method (100) for plastic containers with a blow molding machine, wherein preforms made of plastic are heated with a heating device and introduced into blow molds (101), the preforms in the blow molds then during a first forming phase with a first blowing pressure to pre-blow bottles (102) and then during a second forming phase with a second blowing pressure that is higher than the first blowing pressure to form finished plastic containers (104), the finished plastic containers being demolded from the blow molds after the second forming phase (105), and with selected pre-blow bottles after the first forming phase For example, their temperature distribution, their material distribution, their material properties and / or their shape are inspected and inspection data are determined in order to monitor the manufacturing process for the plastic containers and / or to change at least one process parameter (103).

Description

The invention relates to a manufacturing method for plastic containers and a blow molding machine for manufacturing plastic containers with the features of the preamble of claims 1 and 11, respectively.

As is known, plastic containers can be produced from preforms using a blow molding machine. The preforms made of plastic are first heated with a heating device, for example with an oven, and introduced into blow molds. In the blow molds, the preforms are then subjected to a first blowing pressure during a first forming phase and formed into pre-blow bottles. During a subsequent, second forming phase, the pre-blow bottles are then formed into the finished plastic containers with a second blowing pressure that is higher than the first blowing pressure and then removed from the mold. In addition, it is known to use stretching rods in such blow molding machines in order to stretch the preforms during the deformation, in particular during the first deformation phase.

Various methods are known for monitoring the manufacturing process in order to record the material distribution of finished plastic containers.

The EP 1 175 990 B1 discloses an automated control of the material distribution in a stretch blow molded article, each preform having at least one indicator at a predetermined position along the axial extent of the preform which is then transformed during blow molding and subsequently detected. The material distribution of the blown containers is recorded and included in the process.

The EP 3 033 215 B1 discloses mold control systems and methods. Here, the produced containers are captured as an image with a camera and information on clarity and crystallinity is derived from this, which is then included in a model.

In addition, from the US 7,374,713 B2 and US 2017/0322018 A1 Methods are known in which the wall thickness of containers is measured by the absorption of light.

The disadvantage of the known devices and methods is that they often do not work precisely enough to adequately monitor all parameters of the manufacturing process.

Furthermore, the US 9,676,158 B2 a method for the production of containers from preforms, in which a feedback takes place as a function of a minimum pressure in a pre-blowing curve. However, the evaluation of the pre-blowing curve is often not precise and clear enough to draw conclusions about the material distribution, degree of stretching and the bottle quality.

The DE 10 2008 032 121 A1 discloses a device for expanding preforms into plastic containers with wireless temperature detection for monitoring the temperature of the blow molds.

The object of the present invention is therefore to provide a manufacturing method and a blow molding machine for plastic containers with which more precise process monitoring is possible.

To solve this problem, the invention provides a manufacturing method for plastic containers with a blow molding machine according to claim 1. Advantageous embodiments of the invention are specified in the subclaims.

Extensive investigations have shown that the pre-blow bottles are particularly characteristic of the forming in the blow molds and the process parameters set for them (for example, the performance of a blow molding station, a pre-blow start, a final blow pressure, a pre-blow end, a flow rate, a heating parameter and / or a stretching speed). The pre-blow bottles are not yet in contact with the blow molds in the area of their container bodies, but the quality of the finished plastic container can be inferred particularly well from their temperature distribution, their material distribution, their material properties and / or their shape.

The fact that selected pre-blow bottles are inspected for their temperature distribution, their material distribution, their material properties and / or their shape after the first forming phase, for example, and inspection data are determined, the manufacturing process for plastic containers can be monitored particularly precisely, for example with regard to an expected quality of the finished plastic containers and / or with regard to the process parameters. In addition, the shape and properties of the finished plastic containers can be controlled particularly precisely using the process parameters.

The manufacturing method for plastic containers with a blow molding machine can be used in a beverage processing plant. In particular, the production method can be carried out with a blow molding machine. Preferably, the preforms, the pre-blown bottles and / or the finished plastic container during the Production transported with one or more carriers. The blow molds can preferably be arranged on a conveyor, in particular on a carousel, so that the preforms, the pre-blow bottles and / or the finished plastic containers are transported during the first and second forming phases. After demolding, the finished plastic containers can be transported on to a filler and / or closer, where they are filled and / or closed with a flowable product, for example with a beverage product. The filled plastic containers can then be packed into bundles and / or palletized using a packaging machine.

The finished plastic containers can be provided to accommodate the flowable product, in particular the beverage product. The plastic of the preforms can specifically be a PET, PEN, HD-PE or PP plastic. The plastic containers can be designed as bottles, for example.

The term “pre-blow bottle” can mean an intermediate form between the preforms and the finished plastic container. In particular, the pre-blow bottle can have less than 95% internal volume of the finished plastic container. In other words, it can be an intermediate mold in which the pre-blow bottle does not yet completely rest against the blow molds from the inside during reshaping in the region of the container body. Likewise, a “pre-blowing bottle” can mean an intermediate form in which the second blowing pressure has not yet been reached 100%.

It is conceivable that the preforms made of plastic are heated in an oven as a heating device. For example, the preforms can be irradiated with at least one infrared radiation source for heating. In addition, the preforms and / or the pre-blow bottles in the blow molds can be heated with further heating devices during the first and / or second forming phase in order to control a temperature profile during the forming.

The preforms and the pre-blow bottles can be subjected to the first blow pressure and / or the second blow pressure through blow nozzles assigned to the blow molds. The blow nozzles can each seal the blow molds during forming, so that the first and second blow pressure cannot escape. The blow molding machine can be designed as a stretch blow molding machine. The preforms can be stretched by means of stretching rods during the first and / or second forming phase. The stretching rods can each be assigned to one of the blow nozzles and / or one of the blow molds.

The blow molds can consist of several parts that are moved apart when demoulding. In addition, the blow molds can each include an opening into which the preforms are introduced and / or which are sealed with the blow nozzles during shaping.

It is conceivable that the heating of the preforms with the heating device, the reshaping of the preforms during the first reshaping phase into the pre-blown bottles, the reshaping of the pre-blown bottles during the second shaping phase into the finished plastic containers and / or the demolding of the finished plastic containers from the blow molds with a control unit is controlled and / or regulated. For example, with the control unit, a temperature parameter of the heating device, the first blowing pressure, the start and / or end time for the application of the first blowing pressure, a first blowing curve, the second blowing pressure, a start and / or an end time for the application of the second Blowing pressure, a second blowing curve, at least one flow rate for the first and / or second blowing pressure, a stretching speed and / or temperature parameters of the further heating devices in the blow molds can be controlled.

It is conceivable that the first blowing pressure is changed according to a first blowing curve during the first forming phase. During the second forming phase, the second blowing pressure can be changed according to a second blowing curve. In other words, the first blowing pressure and / or the second blowing pressure can run dynamically. However, it is also conceivable that they run statically, i.e. constancy. The fact that the second blowing pressure is higher than the first blowing pressure can mean here that the second blowing pressure at the beginning or at any point in time during the second forming phase exceeds the first blowing pressure at the end of the first forming phase. In other words, the first forming phase can comprise a plurality of first partial phases with correspondingly assigned first blowing pressures. It is also conceivable that the second forming phase comprises a plurality of second partial phases with correspondingly assigned second blowing pressures. Correspondingly, the plurality of second blowing pressures can be higher than the maximum pressure of the plurality of first blowing pressures.

The fact that the temperature distribution of the selected pre-blow bottles is inspected can mean here that the temperature is determined at at least two points on each of the selected pre-blow bottles, in particular a flat distribution on at least one section. The fact that the selected pre-blow bottles are inspected for their material distribution can mean here that at least partially a local distribution of the material is inspected in each case in one of the selected pre-blow bottles. “Partly” can mean here that the local distribution of the material in a section of one of the selected pre-blow bottles is inspected, for example on the container body. A material property can mean here, for example, a crystallinity, a clarity and / or a color distribution. It is conceivable that a local distribution of the material property is inspected at least in a subsection of one of the selected pre-blow bottles. The fact that the shape of the selected pre-blow bottles is inspected can mean that their surface is recorded three-dimensionally with several coordinates. It is conceivable that this takes place in each case for one of the selected pre-blow bottles at predetermined measuring points and / or over an area.

A prediction model for the pre-blow bottles can be trained on the basis of the inspection data, so that the properties of the pre-blow bottles can be predicted using the prediction model based on the process parameters. This makes it possible to virtually predict the influence of the process parameters on the manufacturing process, so that the process parameters can then be manipulated in a targeted manner. With process parameters, for example, the temperature parameters of the heating device, the first blowing pressure, the start and / or the end time for the application of the first blowing pressure, the first blowing curve, the second blowing pressure, the start and / or the end time for the application of the second Blowing pressure, the second blowing curve, the at least one flow rate for the first and / or second blowing pressure, the stretching speed and / or the temperature parameters of the further heating devices in the blow molds are meant. The prediction model can include, for example, a learning algorithm, artificial intelligence and / or “deep learning”. The prediction model can be designed to predict the properties of the pre-blow bottles from the process parameters. The properties can mean the temperature distribution, the material distribution, the material properties and / or the shape of the pre-blow bottles.

The finished plastic containers can partially be inspected with regard to at least one quality feature, a correlation being determined between the inspection data of the selected pre-blow bottles and the quality features of the finished plastic containers. This allows conclusions to be drawn from the properties of the pre-blow bottles on the finished plastic containers, so that the manufacturing process can be monitored even more specifically. It is conceivable that the prediction model for the pre-blow bottles is trained on the basis of the inspected quality features of the finished plastic containers. This enables the prediction model to predict the properties of the pre-blow bottles even more precisely. “Quality features of the finished plastic container” can mean a material distribution, degree of stretching, crystallinity and / or clarity of the finished plastic container.

The selected pre-blowing bottles can be recorded as camera images during inspection with at least one camera and / or with at least one infrared camera, the inspection data being determined from the camera images. As a result, the temperature distribution, the material distribution, the material property and / or the shape can be recorded particularly easily. With the at least one infrared camera, it is particularly easy to determine the temperature distribution of the selected pre-blow bottles. It is also conceivable that at least one light source and with the at least one camera or with at least one photosensor in transmitted light are used to determine absorption properties of the selected pre-blow bottles, for example in order to determine the material distribution or the material property.

The selected pre-blow bottles can be inspected in the blow molds. This allows the selected pre-blown bottles to be inspected during the forming process and without environmental influences after the removal from the mold. In addition, the selected pre-blown bottles can go through the second forming phase after the inspection, so that they are formed into the finished plastic containers. This prevents the selected pre-blow bottles from being rejected. It is conceivable that sensors such as temperature sensors, cameras, infrared cameras, photo sensors and / or light sources are arranged in the blow molds for this purpose.

Alternatively, it is conceivable that the selected pre-blow bottles are inspected at an outlet or downstream of the blow molding machine. As a result, the blow molds can be designed more easily and without sensors. It is conceivable that the selected pre-blow bottles are inspected during transport at the outlet or downstream of the blow molding machine. The sensors, such as, for example, a temperature sensor, a camera, an infrared camera, a photo sensor and / or a light source, can be arranged at the outlet or downstream of the blow molding machine. The selected pre-blown bottles can then be discharged from a main container flow with the finished plastic bottles after the inspection at the outlet or downstream of the blow molding machine. This prevents the selected pre-blow bottles from passing through further treatment stations. For example, they can be discharged with a switch or the like.

The preforms can be provided with markings, the positions of the markings being determined during the inspection of the selected pre-blow bottles in order to draw conclusions about the material distribution and / or the shape. Because the markings move accordingly from the preforms to the pre-blown bottles during the forming process, it is possible to analyze particularly well in which area the pre-blown bottles have been stretched more or less.

It is conceivable that one of the selected pre-blow bottles is reshaped in a first blow mold during a first shaping phase, with at least one of the process parameters for at least one other, second blow mold then being changed on the basis of the inspection of the one selected pre-blow bottle. This means that fewer of the pre-blow bottles need to be inspected and the process parameters can be passed on to other blow molds. For example, the process parameters of the first blow mold and an associated blow nozzle can be found to be good and then transferred to the at least one other, second blow mold.

In addition, the invention provides a blow molding machine for producing plastic containers with the features of claim 11 to solve the problem. Advantageous embodiments are mentioned in the subclaims.

Because one or more inspection units are assigned to the blow molding machine, which are designed to inspect the selected pre-blow bottles after the first forming phase, for example for their temperature distribution, their material distribution, their material properties and / or their shape and thereby to determine the inspection data the blow molding machine can be monitored particularly precisely, for example with regard to an expected quality of the finished plastic container and / or with regard to process parameters of the blow molding machine. In addition, the shape and properties of the finished plastic containers can be controlled particularly easily using the process parameters.

The blow molding machine can be designed to carry out the above-described manufacturing method for plastic containers, in particular according to one of claims 1-10. The blow molding machine can include individual features or any combination of features previously described in relation to the manufacturing method.

The blow molding machine can be arranged in a beverage processing plant. The blow molding machine can be arranged upstream of a rinser, a filler, a closer, a labeling machine, a direct printing machine and / or a packaging machine.

The blow molding machine can preferably be designed as a stretch blow molding machine, a stretching rod being assigned to each of the blow nozzles and / or blow molds in order to stretch the preforms and / or the pre-blow bottles during shaping. One of the blow nozzles can preferably be assigned to each of the blow molds. The blow molding machine can comprise a conveyor at which the blow station, each with one of the blow molds and with one of the blow nozzles are arranged. The blowing stations can preferably each comprise a stretching rod. The conveyor can preferably be a carousel on which the blow molds and blow nozzles and, optionally, the stretching rods are arranged so as to run along. Further transporters can be assigned to the transporter, in particular a transport star at the inlet and another transport star at the outlet.

The inspection units can be integrated in the blow molds, so that the selected pre-blow bottles can be inspected in the blow molds. As a result, the selected pre-blow bottles can be inspected after demoulding without environmental influences. For example, cameras, pressure sensors and / or temperature sensors can be integrated as inspection units in the blow molds.

The one or more inspection units can be arranged at an outlet or downstream of the blow molding machine in order to inspect the selected pre-blow bottles after they have been removed from the mold. As a result, the blow molds can be designed more easily and without sensors. The one or more inspection units can preferably be arranged on a conveyor. The blow molding machine can include a discharge device, in particular a switch, in order to discharge the selected pre-blow bottles before or after the inspection. This means that the selected pre-blown bottles that can no longer be used can be recycled or disposed of after the inspection.

It is conceivable that the one or more inspection units for inspecting the selected pre-blow bottles comprise a camera and / or an infrared camera in order to determine the inspection data from camera images. As a result, the temperature distribution, the material distribution, the material property and / or the shape can be recorded in a particularly simple, spatially resolved manner. It is also conceivable that the one or more inspection units comprise a temperature sensor, a light source and / or a photo sensor in order to determine the inspection data.

• 1 ein Ausführungsbeispiel eines erfindungsgemäßen Herstellungsverfahrens für Kunststoffbehälter mit einer Blasformmaschine nach der 2 bzw. 5 als Flussdiagramm;
• 2 ein Ausführungsbeispiel einer erfindungsgemäßen Blasformmaschine zur Durchführung des Herstellungsverfahrens aus der 1 in einer Draufsicht, wobei ausgewählte Vorblasflaschen an einem Auslauf der Blasformmaschine inspiziert werden;
• 3A - 3C ein Vorformling, eine Vorblasflasche und ein fertiger Kunststoffbehälter beim Umformen in einer Blasform der Blasformmaschine aus der 2 in seitlichen Schnittansichten;
• 4A - 4C verschiedene Vorblasflaschen in seitlichen Ansichten, die während der ersten Umformphase mit unterschiedlichen Prozessparametern umgeformt sind;
• 5 ein weiteres Ausführungsbeispiel einer erfindungsgemäßen Blasformmaschine zu Durchführung des Herstellungsverfahrens aus der 1 in einer Draufsicht; und
• 6 eine Vorblasflasche bei der Inspektion in einer Blasformen der Blasformmaschine aus der 5 in einer seitlichen Schnittansicht.

Further features and advantages of the invention are explained in more detail below with reference to the exemplary embodiments shown in the figures. It shows:

• 1 an embodiment of a manufacturing method according to the invention for plastic containers with a blow molding machine according to the 2 or. 5 as a flow chart;
• 2 an embodiment of a blow molding machine according to the invention for performing the manufacturing method from FIG 1 in a plan view, wherein selected pre-blow bottles are inspected at an outlet of the blow molding machine;
• 3A - 3C a preform, a pre-blow bottle and a finished plastic container being formed in a blow mold from the blow molding machine 2 in side sectional views;
• 4A - 4C side views of various pre-blow bottles that are formed with different process parameters during the first forming phase;
• 5 Another embodiment of a blow molding machine according to the invention for performing the manufacturing method from FIG 1 in a plan view; and
• 6th a pre-blow bottle during the inspection in a blow molding of the blow molding machine from the 5 in a side sectional view.

• Zu sehen ist, dass die Vorformlinge 10 im Schritt 101 zunächst in der Wärmeeinrichtung 2 erhitzt werden. Beispielsweise kann die Wärmeeinrichtung 2 als Ofen ausgebildet sein, indem die Vorformlinge 10 beim Durchlaufen über eine Glasübergangstemperatur hinaus soweit erwärmt werden, dass sie nachfolgend in den Blasformen 3 umgeformt werden können. Denkbar ist beispielsweise, dass die Wärmeeinrichtung 2 mit Infrarotstrahlen ausgebildet ist, um die Vorformlinge zu erhitzen. Nach der Wärmeeinrichtung 2 werden die Vorformlinge über einen Transportstern jeweils in eine Blasformen 3 am Karussell 5 eingebracht und während des Transports in der Richtung R zu fertigen Kunststoffbehältern umgeformt.

In the 1 is an embodiment of a manufacturing method according to the invention 100 for plastic containers 12th with a blow molding machine 1 after 2 or. 5 shown as a flow chart. The manufacturing process 100 is initially based on the in the 2 illustrated embodiment of a blow molding machine according to the invention 1 explained in more detail:

• It can be seen that the preforms 10 in step 101 first in the heating facility 2 be heated. For example, the heating device 2 be designed as a furnace by the preforms 10 when passing through a glass transition temperature are heated to such an extent that they are subsequently in the blow molds 3 can be reshaped. It is conceivable, for example, that the heating device 2 is formed with infrared rays to heat the preforms. After the heating device 2 the preforms are each placed in a blow mold via a transport star 3 at the carousel 5 introduced and formed into finished plastic containers during transport in the direction R.

In the 3A - 3C are a preform 10 , a pre-blow bottle 11 and a finished plastic container 12th when forming in a blow mold 3 the blow molding machine 1 from the 2 shown in side views.

Can be seen in the 3A that the preform 10 Is designed like a sleeve and consists of a PET plastic here only by way of example. At the top of the preform 10 there is a collar and a thread for a container closure in the usual manner. The preform 10 becomes during the step 101 through the opening 3.1 from above into the closed blow mold 3 introduced, which then with the air nozzle 4th is sealed pressure-tight. The air nozzle 4th includes a fluid supply 4.1 for a pressurized fluid, around the preform or the pre-blow bottle 11 to be reshaped by pressure. The horizontal bar can also be seen 8th for stretching the preforms 10 and the pre-blow bottles 11 during forming. The stretching rod can be moved in the S direction by means of a control cam or a drive.

The preforms are then made in step 102 formed into the pre-blow bottles in the blow molds during a first forming phase with a first blowing pressure. This is more precise in the 3B shown. For this purpose, the fluid is supplied via the fluid supply 4.1 into the preform with the first blowing pressure 10 pressed in so that it goes to the pre-blow bottle 11 is inflated. It is conceivable that a pressure curve is provided for the first blowing pressure according to a first blowing curve. It can also be seen that the horizontal bar 11 during the first forming phase along the direction S into the blow mold 3 is pressed in, so that the preform 10 or the pre-blow bottle 11 is additionally stretched. As a result, the material distribution, the material properties and / or the shape of the pre-blow bottle 11 by the first blowing pressure and the pushing in of the stretching rod 11 being controlled.

Then the pre-blow bottles 11 according to the 3C and step 104 in a second forming phase with a second blowing pressure, which is higher than the first blowing pressure, to the finished plastic containers 12th reshaped. For this purpose, the fluid is supplied via the fluid supply 4.1 supplied with the second blowing pressure. It is conceivable that the second blowing pressure is changed along a second blowing curve. At the end of the second forming phase, the container body of the finished plastic container is then located 12th from the inside of the blow mold 3 at. In addition, the stretching rod can also be used during the second forming phase 8th still further in the direction S into the blow molds 3 be pushed in.

Then the finished plastic containers 12th in step 105 from the Blow molding 3 demolded. It is conceivable that the plastic container 12th can be transported directly to further treatment steps, for example to a filler and a closer.

Can also be seen in the 2 that at the outlet 13th the blow molding machine 1 an inspection unit 6th is arranged to the selected pre-blow bottles 11 after the first forming phase, for example, to inspect their temperature distribution, their material distribution, their material properties and / or their shape and thereby determine inspection data.

To do this, the selected pre-blow bottles run through 11 the steps 104 and 105 after 1 not, but after the first forming phase in the step 102 not further reshaped. You will then be at the outlet 13th with the inspection unit 6th inspected (step 103 ). For example, the inspection device comprises 6th a camera and / or an infrared camera to determine the shape, the temperature distribution or the material distribution of the selected pre-blow bottles 11 to be determined as inspection data. For example, the shape in the camera images can be captured from the side and evaluated by means of image evaluation. It is also conceivable that the temperature distribution of the selected pre-blow bottles can be measured with the infrared camera 11 determined and optionally inferred about the material distribution.

By having the selected pre-blow bottles 11 after the first forming phase 102 For example, their temperature distribution, their material distribution, their material properties and / or their shape are inspected and inspection data are determined in the process (step 103 ), the manufacturing process can 100 for plastic containers 12th be monitored particularly closely, for example with regard to an expected quality of the finished plastic container 12th and / or with regard to the process parameters. In addition, the shape and properties of the finished plastic container can be determined using the process parameters 12th particularly easy to control.

Furthermore, in the 2 the discharge device 7th to see with which the selected pre-blow bottles 11 from the main container flow with the finished plastic containers 12th be discharged. The inspected pre-blow bottles 11 can then be recycled or disposed of.

In addition, it is with the inspection unit 6th or a further inspection unit, not shown here, possible in step 106 the finished plastic containers 12th to inspect for quality characteristics, which then with the inspection data of the selected pre-blow bottles 11 be correlated. This allows conclusions to be drawn about the properties of the pre-blow bottles 11 on the finished plastic container 12th be drawn so that the manufacturing process 100 can be monitored even more specifically.

In step 107 is then based on the inspection data from the step 103 a prediction model is trained for the pre-blow bottles, so that properties of the pre-blow bottles can be used with the prediction model on the basis of the process parameters 11 are predictable. This makes it possible to control the influence of the process parameters on the manufacturing process 100 can be virtually predicted so that the process parameters can then be manipulated in a targeted manner. With process parameters, for example, the temperature parameters of the heating device 2 , the first blowing pressure, the first blowing curve, the second blowing pressure, the second blowing curve, the stretching speed of the stretching rod 8th and / or the temperature parameters of the further heating devices in the blow molds 3 be meant.

It is conceivable that one of the selected pre-blow bottles 11 in a first blow mold 3 is deformed during the first deformation phase, after which on the basis of the inspection of the one selected pre-blow bottle 11 at least one of the process parameters for at least one other, second blow mold 3 is changed. This means that fewer pre-blow bottles need to be used 11 can be inspected and the process parameters can be applied to other blow molds 3 be inherited. For example, the process parameters of the first blow mold 3 and an associated blow nozzle 4th are found to be good and then on the at least one other, second blow mold 3 be transmitted.

In the 4A - 4C are different pre-blow bottles 11A-11C shown in side views during the first forming phase 102 were formed with different process parameters.

It can be seen that during the first forming phase 103 the pre-blow bottles 11A , 11B and 11C were reshaped in this order with an increasing, first blowing pressure. It can be seen that as the first blowing pressure increases, the upper area A is in relation to the lower area B of the pre-blowing bottles 11A-11C is made increasingly larger. This is due to the fact that the lower area of the preforms 10 is thick-walled than the upper area. Correspondingly, via the first blowing pressure during the first forming phase in step 102 the material distribution of the pre-blow bottles 11A-11C controlled in a targeted manner.

In the 5 is a further embodiment of a blow molding machine according to the invention 1 to carry out the manufacturing process from the 1 shown in a top view. It differs from the embodiment in FIG 2 only by the fact that the inspection device 6th here not at the outlet of the blow molding machine 1 is arranged, but that the blow molding 3 are each designed with an inspection device 6 '. This allows the selected pre-blow bottles 11 can be inspected after demoulding without environmental influences. All other features from the exemplary embodiment of 2 apply accordingly.

In the 6th is a pre-blow bottle 11 during the inspection in the blow mold 3 the blow molding machine 1 from the 5 shown in a side sectional view. It can be seen that the inspection facility 6 ' designed as an infrared camera and in the bottom of the blow mold 3 is arranged so that it is the pre-blow bottle 11 captured from below. This makes a floor area particularly good 11.1 the pre-blow bottle 11 are recorded, which will later be the container bottom of the finished plastic container 12th forms. For example, the temperature distribution of the forecourt container can thereby 11 on the floor area 11.1 detected and inferred about its material distribution and / or material properties.

Then the pre-blown bottles are inspected 11 in the previously described step 104 during the second forming phase with the second blowing pressure, which is higher than the first blowing pressure, to the finished plastic containers 12th reshaped. Consequently, it is with an arrangement of the inspection units 6 ' in the blow molds 3 no longer necessary, pre-blow bottles 11 after the blow molding machine 1 out of the main container flow.

It goes without saying that the features described in the exemplary embodiments are not restricted to this combination of features, but are also possible individually or in any other combinations.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 1175990 B1 [0004]
• EP 3033215 B1 [0005]
• US 7374713 B2 [0006]
• US 2017/0322018 A1 [0006]
• US 9676158 B2 [0008]
• DE 102008032121 A1 [0009]

Claims (15)

Manufacturing method (100) for plastic containers with a blow molding machine, wherein preforms made of plastic are heated with a heating device and introduced into blow molds (101), the preforms in the blow molds then during a first forming phase with a first blowing pressure to pre-blow bottles (102) and then during a second forming phase with a second blowing pressure that is higher than the first blowing pressure to form finished plastic containers (104), and wherein the finished plastic containers are demolded from the blow molds (105) after the second forming phase, characterized in that selected pre-blow bottles according to During the first forming phase, for example, their temperature distribution, their material distribution, their material properties and / or their shape are inspected and inspection data are determined in order to monitor the manufacturing process for the plastic containers and / or to change at least one process parameter (103). Manufacturing process (100) according to Claim 1 , wherein a prediction model for the pre-blow bottles is trained on the basis of the inspection data, so that properties of the pre-blow bottles can be predicted using the prediction model on the basis of the process parameters (107). Manufacturing process (100) according to Claim 1 or 2 wherein the finished plastic containers are partially inspected with regard to at least one quality feature, and wherein a correlation between the inspection data of the selected pre-blow bottles and the quality features of the finished plastic containers is determined (106). Manufacturing method (100) according to one of the preceding claims, wherein the selected pre-blow bottles are captured as camera images during inspection with at least one camera and / or with at least one infrared camera, and the inspection data is determined from the camera images. The manufacturing method (100) according to any one of the preceding claims, wherein the selected pre-blow bottles are inspected in the blow molds. Manufacturing process (100) according to Claim 5 , wherein the selected pre-blown bottles go through the second forming phase after the inspection, so that they are formed into the finished plastic containers. The manufacturing method (100) according to any one of the preceding claims, wherein the selected pre-blow bottles are inspected at an outlet or downstream of the blow molding machine. Manufacturing process (100) according to Claim 7 , the selected pre-blown bottles being discharged from a main container flow with the finished plastic bottles after the inspection at the outlet or downstream of the blow molding machine. Manufacturing method (100) according to one of the preceding claims, wherein the preforms are provided with markings, and wherein when inspecting the selected pre-blow bottles, positions of the markings are determined in order to draw conclusions about the material distribution and / or the shape. Manufacturing method (100) according to one of the preceding claims, wherein one of the selected pre-blow bottles is reshaped in a first blow mold during the first shaping phase, and then based on the inspection of the selected pre-blow bottle at least one of the process parameters for at least one other, second blow mold is changed . Blow molding machine (1) for producing plastic containers (12), in particular for carrying out the production method (100) according to one of the Claims 1 - 10 , with a heating device (2) to heat preforms (10) made of plastic, and with blow molds (3) and blow nozzles (4) which are designed to pre-blow the preforms (10) during a first forming phase with a first blowing pressure (11) and then, during a second forming phase, to form finished plastic containers (12) with a second blowing pressure which is higher than the first blowing pressure, characterized in that the blow molding machine (1) has one or more inspection units (6, 6 ') which are designed to inspect selected pre-blow bottles (11) after the first forming phase, for example for their temperature distribution, their material distribution, their material properties and / or their shape and thereby to determine inspection data. Blow molding machine (1) according to Claim 11 , wherein the inspection units (6 ') are integrated in the blow molds (3), so that the selected pre-blow bottles (11) in the blow molds (3) can be inspected. Blow molding machine (1) according to Claim 11 , wherein the one or more inspection units (6) is arranged at an outlet (13) or downstream of the blow molding machine (1), around the to inspect selected pre-blow bottles (11) after demolding. Blow molding machine (1) according to Claim 13 , wherein the blow molding machine (1) comprises a discharge device (7), in particular a switch, in order to discharge the selected pre-blow bottles (11) before or after the inspection. Blow molding machine (1) according to one of the Claims 11 - 14th wherein the one or more inspection units (6, 6 ') for inspecting the selected pre-blowing bottles (11) comprise a camera and / or an infrared camera in order to determine the inspection data from camera images.

Images