Device and method for shaping plastic parisons into plastic containers with valve wear check

Abstract

The invention relates to a device and a method for forming plastic parisons into plastic containers with valve wear check. The invention relates to a device (100) for shaping plastic preforms (V) into plastic containers (F), comprising a movable carrier (22) on which a plurality of shaping stations (24) for shaping the plastic preforms (V) into the plastic containers (F) are arranged, the shaping stations (24) each having a valve assembly (80), the valve assemblies (80) are arranged on the plastic parisons (V) in order to apply a flowable and in particular gaseous medium to the plastic parisons (V) in order to expand the plastic parisons (V), and wherein each of the valve assemblies (80) has at least two controllable valve devices (60), the valve devices (60) having a movable piston device (75), the piston devices can switch the valve devices (60) between at least two valve positions, characterized in that the device has a monitoring device for checking the wear state of at least one of the valve devices, the monitoring device has at least one detection device (64) for detecting the wear state of at least one of the valve devices, the detection device is adapted and ascertained for optically and contactlessly detecting the wear state of the valve device (60).

Description

Technical Field

[0001] The invention relates to an apparatus and a method for forming a plastic preform into a plastic container and to a valve device. The invention is described with reference to a valve device for controlling the blowing air for inflating the plastic preform.

[0002] However, it should be noted that the present invention is also applicable to other valve devices, particularly valves for air. In addition, the present invention can also be used for other types of valves, which are used for other flowable media, such as water, oil, steam, etc. Background Art

[0003] Such machines are known from the prior art for a long time in the form of blow molding machines, for example. These blow molding machines usually have valve assemblies which apply different pressures to the plastic parison to be expanded. For this purpose, these valve assemblies each have a plurality of valve devices.

[0004] In many machines, such valve devices are installed in hard-to-reach areas of the machine. Furthermore, in the prior art, there is hardly any possibility to check the wear state of these valves. In the applicant's not yet published patent application DE 10 2022 105 440 A1, a device and a method for checking the wear of such valves are proposed. The patent is based on an electrical check of the wear state. Summary of the invention

[0005] The object of the invention is to create a possibility for creating a wear state of these valves, in particular valves of a device for molding plastic preforms into plastic containers, in particular plastic bottles.

[0006] According to the invention, this object is achieved by a device and a method according to the independent claims. Advantageous embodiments and developments are the subject matter of the dependent claims.

[0007] According to the present invention, the device for molding a plastic preform into a plastic container has a preferably movable carrier, on which a plurality of molding stations for molding the plastic preform into the plastic container are arranged, wherein each of the molding stations has a valve assembly for applying a flowable and in particular gaseous medium to the plastic preform to expand it, and wherein each of the valve assemblies has at least two controllable valve devices, wherein the valve devices have movable piston devices that can switch the valve devices between at least two valve positions, or the piston devices are suitable and determined for switching the valve devices between at least two valve positions.

[0008] According to the invention, the device has a monitoring device for checking the wear state of at least one of the valve devices, wherein the monitoring device has at least one detection device which is suitable and designed to detect the wear state of the valve device by means of electromagnetic radiation and / or in an acoustic and contactless manner.

[0009] Preferably, the wear state is detected optically, in particular by means of light. However, an acoustic version is also conceivable, for example by means of sound waves, in particular by means of ultrasound. Furthermore, it is possible that, for example, X-rays can also be used. The applicant reserves the right to claim acoustic detection of the wear state, in particular by means of sound waves, in particular by means of ultrasound.

[0010] Particularly preferably, the movable carrier is a rotatable carrier.Single forming stations are preferably arranged on the carrier, in particular equidistantly.

[0011] Preferably, the forming stations each have a blow mould in which the plastic parisons can be expanded into plastic containers.

[0012] Furthermore, the forming stations preferably each have a stretching rod which can be inserted into the plastic preforms in order to stretch them in their length direction.

[0013] The individual blow moulds can preferably be opened and closed so that the plastic parisons are introduced therein, and then a flowable medium, in particular compressed air, is applied to the plastic parisons. The flowable medium is therefore in particular (compressed) air, but it is also conceivable that a liquid is applied to the plastic parisons.

[0014] In a further preferred embodiment, the device has at least one pressure accumulator in which the flowable medium can be stored at a predetermined pressure. Preferably, the device has at least two, preferably at least three and preferably at least four pressure accumulators for different pressure levels. Preferably, the pressure accumulators are arranged on the rotatable carrier, on which the forming station is also arranged. In a further preferred embodiment, the pressure accumulator is an annular channel.

[0015] Preferably, these pressure accumulators can be connected to the valve assembly of the individual molding station in flow. It is possible to apply different pressures to the individual molding stations from the individual pressure accumulators through the valve assembly.

[0016] Preferably, the individual forming stations each have an application device in order to apply an individual pressure to the plastic preform. These application devices are preferably movable in the longitudinal direction of the plastic preform and can be fed to the mouth of the plastic preform. It is also conceivable to feed the application device to a support ring of the plastic preform or to a blow mold in which the plastic preform is located.

[0017] In another preferred embodiment, the detection device is suitable and designed for recording a spatially resolved image of at least one component of the valve device. Thus, the detection device can be, for example, a camera or other image recording device.

[0018] Preferably, the component of the device is the above-mentioned piston device, in particular the end of the piston device. However, the component may also be a valve seat, against which the piston device is supported or against which the piston device temporarily rests when the valve device is in a certain position. Preferably, the piston device or the end of the piston device is formed from a softer material than the valve seat. Preferably, the component made of the softer material is checked for wear.

[0019] Preferably, the device has an evaluation device which evaluates at least one image of the valve device recorded by the detection device. The wear state of the valve device, in particular the wear state of the valve piston, can preferably be determined by means of this evaluation.

[0020] In a preferred embodiment, the valve device is a pneumatically or electrically controlled valve, or a solenoid valve, i.e., a magnetically controlled valve. In a preferred embodiment, the valve device has a control valve and a pilot valve. The control valve is preferably an electrically or pneumatically controlled valve.

[0021] In a preferred embodiment, the detection device is suitable and designed to detect the state of the valve device when the valve device is in a predetermined state, for example when the valve device is in an open or closed state. It is possible to monitor the wear state in continuous operation and / or in an online manner. However, it is also possible to monitor the wear state when the device is in maintenance operation or in response to an error message.

[0022] In another preferred embodiment, at least one valve device has a housing in which the piston device is movable, and the detection device is suitable and determined for detecting the wear state of the valve device through the wall of the housing, or the detection device is integrated into the housing, in particular into the wall of the housing.

[0023] In one embodiment, the detection device is arranged outside the housing and can detect the wear state of the piston device and / or the valve seat through the components of the housing wall. For this reason, the detection device can preferably take at least one image of the piston device and / or the valve seat.

[0024] However, it is also possible that the detection device is directly integrated into the housing, in particular into the wall of the housing. Like this, for example, the observation window of the detection device can also form a part of the inner wall of the valve device.

[0025] However, the valve device is preferably removable from the housing and / or mountable on the housing. If the detection device is integrated into the housing, it is preferably integrated into a region of the housing in which there are no sealing devices (such as O-rings etc.) for sealing the piston device relative to the housing or guide devices for guiding the valve piston.

[0026] In a further advantageous embodiment, the housing has at least one wall portion which is transparent to light, in particular to visible light, and the detection device is preferably adapted and designed to observe the wear state of the valve device through the transparent wall portion. In this embodiment, it is also possible for the machine operator to check its wear state instead of or in addition to the detection device.

[0027] In this way, the detection device can preferably capture an image of the piston device and / or the valve seat through this wall portion. However, it is also conceivable that the entire housing of the valve device is formed from a transparent material, in particular transparent to visible light. However, this material is preferably a material that is resistant to cleaning agents and / or sterilizing agents.

[0028] In this case, the wall portion can be made, for example, of glass or plastic (eg PET), and the housing can also be made, for example, of glass or plastic (eg PET).

[0029] Preferably, the housing is closed at least in the region of the wall portion.

[0030] In a preferred embodiment, the detection device is arranged and / or positioned in such a way that it can observe at least one part of the piston device in all directions, in particular the end portion, so that the wear state of the piston device can be determined in all directions.

[0031] In a preferred embodiment, the detection device is arranged and / or positioned in such a way that the detection device can observe at least one part of the valve seat in all directions, so that the wear state of the valve seat can be determined in all directions.

[0032] In another preferred embodiment, the device has a control device that is suitable and designed to control and / or regulate the device based on at least one value output by the detection device, and / or the device has at least one processor device that is suitable and designed to evaluate at least one value output by the detection device and to output a signal for characterizing the wear state of the valve device.

[0033] In a preferred embodiment, the device, in particular the control device, has a memory device in which images of the valve component, in particular images of the piston arrangement and / or the valve seat, are stored.

[0034] Particularly preferably, the device has a comparison device which is suitable and designed to compare the recorded images of the piston device and / or the valve seat with stored images, in particular in order to be able to output information characterizing the wear state of the valve device in this way.

[0035] In this way, for example, an indication of an impending failure of the valve device can be output. It is also possible to provide the user with information about the expected remaining service life of the valve device.

[0036] Preferably, the spatially resolved images are stored in a storage device. The storage device is preferably a cloud. Preferably, images of other machines are also stored in the storage device, in particular in the cloud, wherein these other machines are preferably machines of the same structure or machines with valves of the same structure.

[0037] In another preferred embodiment, a signal can also be output if wear has already occurred but the valve is still functional. Thus, the operator can order the part to be replaced before the machine is shut down. Optionally, the part can also be ordered automatically.

[0038] It is also conceivable that such a signal is sent to a mobile terminal.

[0039] In another preferred embodiment, the detection device is arranged stationary relative to the valve device. Thus, the detection device can be arranged, for example, in a fixed position, in which the detection device is always suitable for detecting the state of the piston device and / or the valve seat and / or in which the detection device can always capture an image of the valve device.

[0040] In a further preferred embodiment, the detection device is arranged displaceably relative to the valve device.

[0041] Preferably, the detection device is arranged movably in such a way that it can monitor the wear state of several valve devices. It is possible to detect several valves with the aid of one detection device.

[0042] In a preferred embodiment, the detection device is suitable and designed to detect at least one piece of information and / or identification feature that characterizes the molding station to which the valve device is assigned. In this case, the information and / or identification feature can be the station number of the molding station or also a personalized mark arranged at the molding station, such as a QR code or the like. In this way, the value determined for a specific valve device can be assigned to a specific molding station. In this way, it is possible to trace which molding station is worn later.

[0043] In another preferred embodiment, the detection device can be guided on a robot arm. In this way, several valve devices can be monitored in one maintenance operation, for example.

[0044] The detection device may be arranged on a mobile robot. The mobile robot may have several wheels or legs, by means of which it can move. Alternatively, the mobile robot may be a drone that transports the detection device or transports a detection device. The mobile robot may check or detect by sensor not only the valve of one valve device, but also the valves of a plurality of valve devices.

[0045] The valve devices can be arranged on a movable carrier, such as a blowing wheel, along the circumference of the movable carrier. By rotating the blowing wheel, individual valve devices or valves can be presented to a detection device or the detection device in turn.

[0046] Alternatively, a testing device or the testing device can be moved along the circumference of the blow moulding wheel by means of a mobile robot in order to check a plurality of valve devices.

[0047] A mobile robot having a detection device or the detection device can be used for a plurality of valve devices of different devices for molding plastic preforms into plastic containers.

[0048] In another preferred embodiment, the detection device is suitable and designed for monitoring the wear state of several valve devices. Here, the detection device can also be arranged stationary relative to the valve device. In this way, the detection device can be arranged, for example, above several valve devices of the valve assembly and detect the valve pistons of several valve devices.

[0049] Particularly preferably, the valve component is designed in such a way that a rod-shaped body, in particular the above-mentioned stretch rod, can be guided through it.

[0050] As already mentioned above, the wear state can preferably also be detected, in addition to optical methods, using a detection device which is suitable and designed for detecting the state electromagnetically and / or acoustically, in particular by means of electromagnetic radiation and / or acoustic means.

[0051] In the context of electromagnetic testing of the wear state, the detection device preferably has an inductive and / or capacitive sensor. In this case, preferably at least one part of the piston device, in particular at least one part of the end and / or the valve seat, is detected inductively and / or capacitively. The position of the piston device and / or the valve is thus detected.

[0052] Furthermore, the wear state of the valve device can also be checked preferably via a leak test, for example by measuring the flight time of the valve, i.e. the switching time between leaving the starting position and reaching the end position. From this flight time, conclusions can be drawn about the correct functioning of the valve.

[0053] Such a wear check using inductive and / or capacitive sensors can here preferably be carried out at the electrically driven pilot valve and / or the pneumatically driven main valve.

[0054] The inspection or detection of the wear state can preferably be performed by a self-learning system such as artificial intelligence (AI), wherein preferably a trial run can be performed and the AI ​​is trained according to certain patterns or predetermined patterns corresponding to the wear state and / or health state of the relevant components. This can also be done via a so-called DoE (Design of Experiments).

[0055] The evaluation of the data detected by the acoustic sensors and / or AI is preferably performed centrally at the system, or decentralized at another location, and in the latter case transmitted to the system or an operator.

[0056] If the evaluation finds that an error exists and / or that a specific or foreseeable error will occur in the near future, an error message may preferably be output. The error message may preferably be an acoustic and / or visual signal to the operator via a signal lamp at the operator terminal or the system. Preferably, a suggestion for action may also be output together with the error message, such as a suggestion to order spare parts or to replace certain components.

[0057] Preferably, values ​​or limit values ​​characterizing the wear state are predetermined, in particular limit value ranges within which the tool should lie. If these values ​​are undershot or exceeded, wear can be indicated. Preferably, a dynamic limit value setting can also be performed here, so that the limit value is adjusted, preferably automatically, depending on requirements or changing environmental conditions.

[0058] These inductive and / or capacitive measurements can also be preferably performed outside the optical spectrum, for example in the infrared range. For example, additional wear parameters can be identified via the heat distribution in or at the valve piston, which can provide conclusions about preferably future wear.

[0059] X-ray methods are also conceivable, with which the internal structure of the piston, in particular the material structure of the piston, can also be checked, depending on the design of the piston. Preferably, material testing can be carried out with such X-ray methods, in order, for example, to be able to identify weaknesses in the material, in particular in the material of the piston, at an early stage.

[0060] Furthermore, the detection device can preferably also have an acoustic sensor for wear detection. Here, preferably Acoustic position detection is performed on at least one part of the piston arrangement, in particular the end and / or at least one part of the valve seat. The position of the piston arrangement and / or the valve is thus detected. This is preferably done by measuring or detecting vibrations and / or vibration times, for example, of piston impacts or by measuring grinding noises / sliding noises in the valve seat and detecting the position of the piston.

[0061] The wear check can preferably also be performed by means of an acoustic sensor via the switching times of the valve arrangement, wherein the switching time and the impact time of the piston are preferably detected acoustically and the time between these two times is measured.

[0062] As well as inductive and / or capacitive sensors, preferably also acoustic sensors can be used to determine the wear state via the tightness, for example detecting leakage noise in the actual closed state of the valve device. For this purpose, the frequency band can be analyzed, for example, by the user or automatically by an evaluation device.

[0063] Preferably, the acoustic sensor is connected to high-pass and / or low-pass filters that block unwanted noise that might otherwise make acoustic inspection difficult. For example, flow noise from the pilot valve and / or the main valve might be blocked or, as described above, they might also be analyzed to detect abnormal noise.

[0064] In order to check the wear state of the valve device, in a preferred embodiment a diaphragm is arranged on the outside of the valve block or in the interior of the blowing air channel, by means of which diaphragm acoustic vibrations can be recorded, just like a microphone.

[0065] In another preferred embodiment, the wear state check is performed by means of an acoustic method by arranging a microphone. Preferably, each valve block has at least one microphone, and particularly preferably, each valve device or each valve has at least one such microphone.

[0066] As mentioned above, software or artificial intelligence (AI) may also be used to detect and / or check the wear state of the valve arrangement.

[0067] Preferably, for this purpose, the AI ​​is trained using a plurality of good pistons and / or good seals as well as worn pistons and / or worn seals so that these states can be recognized. Here, it is also preferred that an analysis of data measured or detected from a plurality of workstations / machines is provided to the AI ​​and these results are preferably used for assessing the wear state and / or the wear prediction. Preferably, for this purpose and in particular for training the AI, a plurality of different measurement data are used, such as image and acoustic measurement data.

[0068] These data can preferably be superimposed with additional (measured) data, such as the blowing pressure curve (especially its slope) and / or the number of blowing cycles and / or data on the quality of the bottle, such as wall thickness measurements or material distribution.

[0069] If necessary or possible, the AI ​​adjusts the pilot valve, for example, so that the piston is controlled in a gentle manner, for example by building up a small pressure, so that the piston does not hit the valve seat too quickly. However, this adjustment should not reduce the bottle quality. At the same time, the AI ​​can also preferably adjust the extension speed at the switching time of the P1 pilot valve.

[0070] The regulation or control is therefore preferably carried out by the AI ​​in such a way that the AI ​​determines the optimum operating point between bottle mass and valve switching time and controls it accordingly. It may also be possible to preferably use the results of the above-mentioned calorimetry in the valve piston, for example in the infrared range, to determine these switching times.

[0071] The above-described electromagnetic and acoustic methods for checking the state of wear are advantageous because wear of the valve can thereby be detected at an early stage.

[0072] The present invention also relates to a valve device, in particular a valve device for a device of the above-mentioned type, wherein these valve devices have a medium inlet for a flowable medium and a medium outlet for the flowable medium; and have a linearly movable piston device, which is movable between at least two positions of the valve device, wherein in one of the two positions, a medium flow of the flowing medium from the medium inlet to the medium outlet is enabled, and in the other of the two positions, the medium flow of the flowing medium from the medium inlet to the medium outlet is (substantially) blocked or throttled.

[0073] In this case, the valve device has a housing in which a piston device is movable.

[0074] According to the invention, at least one part of the piston arrangement and / or the valve seat is observable by means of an optical detection device, in particular observable through a region of the housing.

[0075] The invention also relates to a monitoring device for monitoring the wear state of a valve device, which comprises a valve device of the above-described type and a detection device which is suitable for detecting and determining at least one wear state of a piston device and / or a valve seat.

[0076] Preferably, the detection device is suitable and designed for recording a spatially resolved image of the piston arrangement and / or the valve seat.

[0077] In a further preferred embodiment, the monitoring device has an evaluation device in order to draw conclusions about the wear state of the valve device from the recorded images of the piston device and / or the valve seat.

[0078] The present invention also relates to a method for molding plastic preforms into plastic containers, wherein a movable, in particular rotatable carrier transports the plastic preforms, and a plurality of molding stations for molding the plastic preforms into plastic containers are arranged on the carrier, wherein each of the molding stations has a valve assembly, by means of which a flowable and in particular gaseous medium is applied to the plastic preform (10) to expand it, and wherein each of the valve assemblies (80) has at least two controllable valve devices (60), wherein the valve devices have movable piston devices, which switch the valve devices between at least two valve positions.

[0079] According to the invention, a monitoring device is provided for checking the wear state of at least one of the valve devices, wherein the monitoring device has at least one detection device which optically detects at least one element of the valve device in order to detect and / or determine the wear state of the valve device in an optical and contactless manner.

[0080] Particularly preferably, the detection device records at least one spatially resolved image of the valve device, in particular the piston device and / or the valve seat (for the piston device). Preferably, the evaluation device evaluates the spatially resolved image in order to determine the wear state of the valve device in this way.

[0081] The present invention also relates to a method for monitoring a valve device of a molding station, in particular a method for monitoring the wear state of a valve device of a molding station, the method comprising the following steps:

[0082] - Switching valve devices to release media under pressure, especially gaseous media

[0083] - The plastic preform is formed into a plastic container with the aid of this medium

[0084] - Use detection equipment to detect the area of ​​the valve device

[0085] - Use the detection device to capture and store image data

[0086] -Generate digital images

[0087] - analyzing the image or the image data using an evaluation device

[0088] -Optionally take action when errors are found

[0089] The detection device is preferably a digital camera.

[0090] Furthermore, the advantageous embodiments and methods described above may also be applied to this method. Thus, the evaluation may be performed using artificial intelligence as described above.

[0091] Preferably, the region of the valve device is the valve piston and / or a part of the valve piston, in particular the end.

[0092] Preferably, the medium under pressure can be introduced into the plastic preform to be expanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] Further advantages and embodiments can be seen from the accompanying drawings:

[0094] in:

[0095] Figure 1 A first embodiment of a valve device according to the invention is shown;

[0096] Figure 2 Shows Figure 1 The wear condition of the valve device shown in;

[0097] Figure 3 A second embodiment of a valve device according to the invention is shown;

[0098] Figure 4 A fourth embodiment of a valve device according to the invention is shown;

[0099] Figure 5 A fifth embodiment of a valve device according to the invention is shown;

[0100] Figure 6 A sixth embodiment of the device according to the invention is shown;

[0101] Figure 7 A valve assembly having a plurality of valve devices is shown; and

[0102] Figure 8 A diagrammatic representation of a device according to the invention for forming plastic preforms into plastic containers is shown. DETAILED DESCRIPTION

[0103] Figure 1 The valve device 60 is shown in a first embodiment. Reference numeral 75 here refers to a valve piston which can be linearly moved between two end positions. Reference numeral 72 denotes a medium inlet via which compressed air can be supplied to the valve device. Reference numeral 74 denotes a medium outlet via which the air present at the medium inlet or pressure inlet 72 can be conveyed further, in particular to the blow mold, when the valve device is in the open state.

[0104] Reference numeral 76 denotes a housing of the valve device 60, within which the piston device 75 is movable. Reference numeral 77 denotes a guide device for guiding the piston device relative to the housing.

[0105] Reference numeral 75a denotes sealing surfaces of the piston arrangement 75, which are here made of a softer material than the valve seat for the piston arrangement 75. In this embodiment, these sealing surfaces 75a are therefore subject to wear. Figure 1 The valve arrangement is shown in the open state with an unworn piston.

[0106] Reference numeral 80 denotes a valve assembly supporting a single valve device, and reference numeral 73 denotes a pilot valve. The pilot valve may be implemented as an electric or pneumatic valve, for example.

[0107] Reference numeral 76a denotes a transparent part of the housing wall through which a detection device, such as a camera, can look into the interior of the housing 76, in particular into the piston device 75, and there in particular into its sealing surface.

[0108] Reference numeral 85 denotes as a whole an evaluation device for evaluating the images captured by the detection device 64 .

[0109] Furthermore, a control device may be provided for controlling corresponding devices, a PLC, an LMS, an Internet connection, a cloud, a database and / or a comparison device.

[0110] Figure 2 Shows Figure 1 Other conditions of the device shown in. Here, the valve device is also open, but the piston device is worn, which can also be detected by the detection device.

[0111] Figure 3 Another embodiment of the valve device according to the invention is shown. In this embodiment, the piston device 75 is made of a relatively hard material, but the sealing surface 80a or the valve seat is made of a soft material, so that the latter is subject to wear. In this embodiment, the detection device 64 looks at the sealing surface of the valve component 80a through the transparent wall part. Correspondingly, the image of the sealing surface captured is preferably evaluated here.

[0112] Figure 3 This shows the condition of the open valve device when the sealing surface 80a is worn.

[0113] Figure 4 A further embodiment of the embodiment according to the invention is shown. Here, the sealing surface 85a is also a wear surface and is observed or detected accordingly. However, other areas of the piston device 75 can also be detected here in addition, for which purpose a further transparent housing part 76b is preferably provided. The detection device 64 can preferably have a larger viewing angle range here, or two detection devices can also be provided.

[0114] Figure 5Another embodiment of the valve device according to the invention is shown. In this embodiment, the entire housing 76 is preferably embodied transparent, whereby the valve device or its inner workings can be inspected from several sides. This makes it possible, for example, to monitor both the piston device 75 and its guide device 77. In addition, it is also possible here to monitor the valve seat.

[0115] Figure 6 A further embodiment of the device according to the invention is shown. In this embodiment, the detection device does not detect the interior of the piston device and / or the housing "from the outside in", but is inserted into the recess. In this way, the detection device can directly observe the piston device and / or the valve seat. Therefore, in this embodiment, the detection device, for example a camera, is an integral part of the housing of the valve device.

[0116] Figure 7 A valve assembly with a plurality of valve devices is shown. Here, a transparent wall section of the housing is provided on the upper side of the valve assembly. A detection device 64 can preferably monitor the inner workings of several and preferably all valve devices, in particular piston devices and / or valve seats. Preferably, the detection device here looks obliquely from top to bottom out of the image plane into the viewing window or the transparent wall section.

[0117] Reference numeral 87 denotes a rod-shaped body or the above-mentioned stretch rod, which is movable within the valve assembly, in particular in the longitudinal direction of the plastic parison to be expanded.

[0118] Figure 8 A schematic top view of a container handling machine or a device for forming plastic parisons into plastic containers in the form of a hollow body manufacturing machine 100 is shown. In the present exemplary embodiment, the device is designed as a continuously operating stretch blow molding machine. The parisons V are fed via a so-called sawtooth star device 140 to a temperature control device 150, in which the parisons V are preferably continuously passed through a heating tunnel (not shown in detail) by means of heating mandrels arranged on a circumferential chain, which advantageously consists of a plurality of infrared radiation heaters and oppositely disposed reflectors.

[0119] Alternatively, the temperature control device 150 may be a rotating device having a plurality of heating stations, such as microwave resonators or heating bags (not shown), mounted at the circumference of the rotating device.

[0120] After temperature control, the parisons V are transferred by grippers 131 circulating on an inlet star 130 to a blow-molding wheel 22 , on the circumference of which a plurality of blow-molding or forming stations 24 are arranged.

[0121] After the forming process is completed in the blow molding station 24, the blown bottle F is taken out by the extraction star device 120. The bottle F is then transported to a labeling device, a filling device and a packaging device not shown in the figure. The transport routes of the parison V and the bottle F are each indicated by an arrow.

[0122] The individual molding or blowing stations 24 are supplied with a gaseous medium, here compressed air, via a compressor 160 having several compressor stages 161. In the first stage (shown on the right), the air is compressed to a pressure of, for example, 5 bar, in the next stage to 10 bar, and so on, until the air has a pressure of 45 bar after the last stage.

[0123] The air is then supplied to a rotary distributor 165 via a delivery line 162, which connects the stationary part of the hollow body manufacturing machine 100 with the rotating part (blowing wheel 22). Several pressure reducers (not shown) are preferably also provided on the rotary distributor 165, which reduce the pressure provided by the compressor 160 to different pressure levels, which are used for the annular lines S1 to S3 which are also preferably mounted on the blowing wheel 170.

[0124] The annular lines S1, S2, S3 serve as pressure accumulators and / or distributors for the individual blowing stations 24 on the blowing wheel 22. In the annular line S3, a pre-blowing pressure of, for example, 10 bar is provided, in the annular line S2, an intermediate blowing pressure of, for example, 20 bar is provided, and in the annular line S1, a final blowing pressure of, for example, 35 bar is provided.

[0125] Each blowing station or forming station 24 here comprises a valve unit or valve assembly 80, which is connected to the individual annular lines S1, S2, S3 and which connects the individual annular lines S1, S2, S3 to the parisons to be blown V. After the parisons V are sealed by the blow-molding nozzle or the application device, the parisons are connected to the individual annular channels in sequence and in the following order: S1, S2, S3.

[0126] After the expansion is completed, the air in the bottle F (still at the final blowing pressure) is preferably first returned to the annular channel S2, advantageously for such a long time until the pressure in the bottle F almost reaches the pressure in the annular channel S2. Subsequently, the air in the bottle F (now approximately at the pressure of the annular channel S2) is supplied to the channel S3.

[0127] If you want to ensure that the minimum pressure is always provided in the pre-blowing channel S3, it can also be advantageous to first use this pre-blowing channel for air recovery. The recovery time can also be adjusted via the pressure in the channels S2, S3, S4 by a pressure sensor (not shown).

[0128] If a sufficient amount of air is recovered, it is also possible to dispense with the pressure reducers which preferably supply pressure to the channels S2 and S3 during production, although they are advantageous for the start-up of the blow molding machine.

[0129] As an alternative to a blow molding machine, the invention can also be used for filling machines (or their product valves, CIP valves, gas valves, etc.) or for all valves, in particular valve nodes, for controlling CIP media or products in the process technology part of a beverage processing process technology component.

[0130] This also includes disk valves, seat valves and double-seat valves. For example, the housing foil of a double-seat valve can be made at least partially of a transparent material so that the seal can be monitored.

[0131] The mobile robot with camera / sensor described above may also be able to check valves at the filling machine and process technology valves. In order to check for wear, it may also be possible for the mobile robot to remove the valves and view them in the disassembled state. For this purpose, the valves can be mounted using quick-release fasteners. As long as it is reasonable, the content of the proposed prior art shall also be part of the technology of the invention.

[0132] The blowing air is then fed back into channel S4 to a level of 3-5 bar, instead of letting the remaining air escape into the atmosphere via outlet E. Since pre-blowing from channel S3 at a certain pressure (here 10 bar) must be the first step in the manufacture of the hollow body, in this embodiment, the annular channel S4 is used exclusively for (temporary) storage or transfer of the circulating blowing air from the bottle F due to its low pressure level, and is not used for blowing.

[0133] From this annular channel, the air can either continue to be supplied to the blow molding wheel 22, for example the pilot valve 9 or other drives of the blow molding station (for example the drive for the stretch rod), or it can be returned to the stationary part of the machine via another line and via a rotary distributor 165 via line 163. From this stationary part, the air can be sent back, for example, to an intermediate stage of the compressor 161 or supplied via line 164 to the plant compressed air network or to another use, for example, for bottle base post-cooling or a labeler or filler.

[0134] The annular conduits S1, S2, S3, S4 may also be designed to be annular only in certain areas. For example, the annular channels S1, S2, S3, S4 may also be formed by two semicircles. Typically, the pressure accumulator will be referred to as S hereinafter.

[0135] The above-mentioned outlet E is present at each station Bs and is used to discharge the remaining 3 bar to 5 bar in the bottle F before the blow molding nozzle 8 is raised again and the bottle F is taken out.

[0136] The applicant reserves the right to claim all features disclosed in the application documents that are essential to the invention, insofar as they are novel compared to the prior art, either individually or in combination. It is further noted that features that can be advantageous in themselves are also described in individual drawings. A person skilled in the art will immediately recognize that a certain feature described in a drawing can be advantageous even without the use of other features in the drawing. In addition, a person skilled in the art will recognize that advantages can also be derived by combining several features shown in a single drawing or in different drawings.

Claims

1. A device (100) for molding a plastic preform (V) into a plastic container (F), the device having a preferably movable carrier (22), on which a plurality of molding stations (24) for molding the plastic preform (V) into the plastic container (F) are arranged, wherein each of the molding stations (24) has a valve assembly (80) for applying a flowable medium to the plastic preform (V) to expand it, and wherein each of the valve assemblies (80) has at least two controllable valve devices (60), wherein the valve device (60) has a movable piston device (75) which is capable of switching the valve device (60) between at least two valve positions, It is characterized in that The device has a monitoring device for checking the wear state of at least one of the valve devices (60), wherein the monitoring device has at least one detection device (64) which is suitable and designed for detecting the wear state of the valve device (60) by means of electromagnetic radiation and / or in an acoustic and contactless manner.

2. The device (1) according to claim 1, It is characterized in that The detection device is suitable for recording a spatially resolved image of at least one component of the valve device.

3. The device (1) according to claim 1, It is characterized in that At least one valve device (60) has a housing (76) in which the piston device is movable, and the detection device is suitable and designed for detecting the wear state of the valve device through a wall of the housing or is integrated into the housing.

4. The device (1) according to claim 1, It is characterized in that The detection device (64) is or has an image recording device.

5. The device (1) according to claim 3, It is characterized in that The housing (66) has at least one wall portion (68) which is transparent to light.

6. The device (1) according to claim 1, It is characterized in that The detection device (64) is suitable and designed for detecting a wear state of the valve piston.

7. The device (1) according to claim 1, It is characterized in that The device (1) has a control device, which is suitable and designed to control the device (1) based on at least one value output by the detection device, and / or the device has at least one processor device, which is suitable and designed to evaluate at least one value output by the detection device and output a signal for characterizing the wear state of the valve device.

8. The device (1) according to claim 1, It is characterized in that The detection device is arranged to be stationary relative to the valve device, or the detection device is arranged to be relatively movable relative to the valve device.

9. A valve device (60), wherein the valve device has a medium inlet (72) for a flowable medium and a medium outlet (74) for the flowable medium; and has a linearly movable piston device, the piston device is movable between at least two positions of the valve device, wherein in one of the two positions, the flow of the flowable medium from the medium inlet (72) to the medium outlet (74) is enabled, and in the other of the two positions, the flow of the flowable medium from the medium inlet (72) to the medium outlet (74) is blocked; and has a housing (76), the piston device (75) is movable in the housing, It is characterized in that At least one part of the piston arrangement (75) and / or the valve seat is observable through a region of the housing (80) by means of an optical detection device (64).

10. The valve device (60) according to claim 9, It is characterized in that The housing has at least one transparent housing part through which the piston device and / or the part of the valve seat can be viewed, and / or the housing has a recess into which the detection device can be inserted.

11. The valve device (60) according to claim 9, It is characterized in that The valve device is a pneumatically or electrically controlled valve device.

12. A monitoring device for monitoring the wear state of a valve device, the monitoring device having a valve device according to claim 9 and having a detection device (64) which is suitable and designed to detect at least one wear state of the piston device and / or the valve seat.

13. A method for molding a plastic preform (V) into a plastic container (F), wherein a movable carrier (22) transports the plastic preform, and a plurality of molding stations (24) for molding the plastic preform into the plastic container (15) are arranged on the carrier, wherein each of the molding stations (24) has a valve assembly (80), by means of which a flowable medium is applied to the plastic preform (V) to expand it, and wherein each of the valve assemblies (80) has at least two controllable valve devices (60), wherein the valve device (60) has a movable piston device, which switches the valve device between at least two valve positions, It is characterized in that A monitoring device is provided for checking the wear state of at least one of the valve devices, wherein the monitoring device has at least one detection device (64) which detects at least one element of the valve device optically in order to detect and / or determine the wear state of the valve device optically and contactlessly.

14. A method for monitoring a valve device (60) of a forming station (24), the method comprising the following steps: - switching the valve device (60) to release the medium under pressure; - shaping the plastic preform (V) into a plastic container (F) with the aid of the medium; - detecting the area of ​​the valve device (60) using a detection device (64); - using the detection device (64) to capture and store image data; - generating a digital image using said image data; - analyzing the image or the image data using an evaluation device; -Optionally take action when errors are found.

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