Process for wall thickness control for blow-moulding machines
Patent Information
- Application Number
- PCT/EP2025/078010
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-13
- Filing Date
- 2025-09-30
- Publication Date
- 2026-09-17
Smart Images
Figure EP2025078010_17092026_PF_FP_ABST
Abstract
Description
[0001] Technology for wall thickness control in blow molding machines
[0002] Description
[0003] The invention lies in the field of manufacturing products from thermoplastic materials by blow molding.
[0004] In practice, it is known to produce a melt tube using a blow molding machine, to insert this into a blow mold and to expand it in order to create a product whose shape is influenced or predetermined by the cavity of the blow mold.
[0005] The products to be manufactured are subject to increasingly stringent requirements regarding one or more wall thickness specifications. It is particularly common to define at least one target wall thickness statically, whereby the actual manufactured wall thickness should correspond as closely as possible to the target wall thickness and may deviate from it only within a certain toleranced range.
[0006] Furthermore, it is known that the output of the melt tube at the extruder head can be influenced.
[0007] Devices for blow molding are known from EP 0105020 A1, EP 4331809 A1, WO 2019 / 063435 A1, DE 38 16273 A1 and EP 0 105 020 A1. These devices use manual wall thickness measurements or measurement methods such as ultrasonic measurement or optical sensors, in particular laser sensors.
[0008] The object of the present invention is to demonstrate an improved technique for wall thickness control in a blow molding machine. The invention achieves this object through the features defined in the independent claims.
[0009] 1088-145PCTThe disclosed technology comprises several aspects which can be used individually or in any combination, in particular a wall thickness control method, a blow molding machine, a wall thickness control for a blow molding machine, a software product (for creating or implementing a wall thickness control) and a blow mold.
[0010] The wall thickness control technology achieves control, in particular regulation, of the wall thickness of the melt tube exiting the extruder head in such a way that the actual wall thickness of the formed product adheres to the wall thickness specifications even faster and / or more precisely. For this purpose, the wall thickness control system and / or the control method processes, on the one hand, a measured wall thickness of the ejected melt tube and, preferably, also a measured wall thickness of the product formed (from this melt tube). At least one of these wall thickness measurements is performed using a radar sensor.
[0011] Advantageously, the manual adjustment of process parameters for calibrating a wall thickness can be dispensed with. The disclosed technique can be used both for setting a wall thickness when the wall thickness is to remain essentially constant along the length and / or circumference of the melt tube. On the other hand, it can be used for setting and, in particular, controlling a wall thickness when a wall thickness profile is to be output, i.e., when the wall thickness is to be specified with changing values along the length and / or circumference of the melt tube.
[0012] The disclosed wall thickness control technique can significantly reduce the amount of rejected products where the wall thickness specifications are (still) not met.
[0013] The wall thickness control can independently react to and compensate for external disturbances. Such disturbances can arise, for example, from changes in ambient temperature, the temperature of the blow mold, or changes in the composition of the melt. Furthermore, contact-based wall thickness measurement, which has proven to be error-prone and time-consuming in practice, can be eliminated.
[0014] The actual hose wall thickness and / or the actual product wall thickness can be measured very quickly. Subsequently, a large number or multiple values for the actual hose wall thickness and / or the actual product wall thickness can be recorded. Data acquisition is preferably digital.
[0015] A recorded value, and in particular each recorded value of an actual hose wall thickness and / or an actual product wall thickness, can be assigned to a section of the melt hose or the product, in particular with a local location.
[0016] A wall thickness control method according to the present disclosure is provided for controlling the wall thickness of a melt tube on a blow molding machine. The blow molding machine comprises an extrusion head, a wall thickness control unit, and at least one blow mold, either provided or associated with the blow molding machine, into which, in particular, the dispensed melt tube can be inserted. The blow molding machine dispenses a melt tube from the extrusion head for the production of a product. The wall thickness control unit adjusts the dispensed melt tube according to a target wall thickness. The method according to the present disclosure provides that the actual wall thickness of the dispensed melt tube is detected by means of a radar sensor. The target wall thickness is adjusted based on the detected actual wall thickness.
[0017] The radar sensor can detect wall thickness without contact and, in particular, non-destructively. Detection can be especially fast and precise. Wall thickness detection using the radar sensor can be achieved by utilizing any physical phenomenon and / or detection principle, in particular by utilizing:
[0018] - Detection of a time-of-flight difference between at least two reflected radar signals; wherein the radar signals are in particular each reflected
[0019] o on an outer surface of the melt tube; AND / OR o on an inner surface of the melt tube; AND / OR o at a layer transition between two different material layers of the melt tube;
[0020] - Detection of an amplitude change of at least one reflected radar signal compared to a transmitted radar signal;
[0021] - Detection of a frequency shift of at least one reflected radar signal relative to an emitted radar signal.
[0022] A radar signal emitted by the radar sensor can strike one or more sections of a melt tube or product. These can be adjacent sections. Alternatively or additionally, the multiple sections can be a section closer to the radar sensor, in particular a front wall section, and a section further away from the radar sensor, in particular a back wall section.
[0023] The radar sensor can detect the wall thickness for exactly one section or for a plurality of sections of the melt tube, in particular as a tube wall thickness profile, which can further be two- or three-dimensional. The wall thickness control method can preferably further provide that an actual product wall thickness of a product, in particular of the product that is formed or will be formed from the dispensed melt tube, is detected by means of a sensor, preferably a radar sensor. The target tube wall thickness can also be adjusted based on the detected actual product wall thickness.
[0024] Local variations in the wall thickness of the melt tube can have several effects. Firstly, a thinner wall area already present in the melt tube may stretch more during expansion than another, thicker wall area. Consequently, an insufficient (local) wall thickness in the melt tube can lead to an even greater, unacceptable reduction in wall thickness in the product. Conversely, an excessive wall thickness in the melt tube can lead to an even greater increase in wall thickness in the resulting product.
[0025] By jointly considering the recorded actual hose wall thickness and the actual product wall thickness, a particularly fast and successful adjustment of the melt hose output can be achieved, which can especially ensure that the wall thickness specifications for the product to be manufactured are reliably met.
[0026] Preferably, the actual product wall thickness can also be recorded for a plurality of sections of the formed product, in particular as a product wall thickness profile, and further in particular as a two- or three-dimensional wall thickness profile.
[0027] A two-dimensional wall thickness profile can preferably be defined in the circumferential direction of the tube and / or the product, or alternatively in the longitudinal direction of the tube and / or the product formed therefrom. The molten tube can be ejected from an extrusion head between a mandrel section (inside the tube) and a nozzle section (outer boundary of the tube).
[0028] The adjustment of the melt tube output according to a target tube wall thickness can be carried out in any way. At least one measure can be provided, which is implemented or instructed by a control intervention, in particular at least one adjustment measure and / or a profiling measure.
[0029] The output adjustment can include at least one of the following measures; the blow molding machine and, in particular, the wall thickness control can be configured for at least one of the following adjustment or profiling measures:
[0030] ■ Gap width adjustment / gap width profiling; in particular by adjusting the gap width between the mandrel section and the nozzle section, especially local adjustment and / or temporal adjustment during output;
[0031] ■ Mandrel body adaptation / mandrel body profiling; In particular by changing the arrangement position of the mandrel section, especially by moving a mandrel body along the output direction of the melt tube and / or transversely to the output direction;
[0032] ■ Nozzle body adaptation / nozzle body profiling; in particular by changing the arrangement position of the nozzle section, especially by moving a nozzle body along the discharge direction of the melt tube and / or transversely to the discharge direction;
[0033] ■ Output current adjustment / output current profiling; in particular by changing the output speed of the melt tube, especially temporarily during the output of the melt tube;
[0034] ■ Material layer adjustment / material layer profiling; in particular by changing the ratio of the addition of two or more melt materials to a multi-layer melt tube;
[0035] ■ Output temperature adjustment / output temperature profiling;
[0036] In particular by changing a local and / or instantaneous output temperature of the molten material along and / or across the output direction of the molten tube.
[0037] The aforementioned measures can essentially make a static adjustment for a single melt tube dispensing process. An adjustment can affect the entire circumference and / or the entire length of the dispensed melt tube.
[0038] In the aforementioned measures, profiling can provide at least two different values for a single melt tube output process. Profiling can have different effects on at least two sections of the melt tube, in particular on two sections along the circumference of the melt tube and / or on two sections along the length of the melt tube.
[0039] The blow molding machine, and in particular the extrusion head, can comprise one or more devices, especially controllable actuators and / or controllable heating or cooling devices, suitable for performing one or more of the aforementioned measures. The blow molding machine, and in particular the wall thickness control, is preferably connected to the at least one controllable actuator and / or the controllable heating or cooling device. The blow molding machine, and in particular the wall thickness control, is configured to output at least one command value for the at least one controllable actuator and / or the controllable heating or cooling device based on the target tube wall thickness, in order to perform at least one adjustment or profiling measure.
[0040] The present disclosure also relates to a software product comprising instructions configured, when executed on a data processing device, to execute a wall thickness control method according to one of the preceding claims. The data processing device may, in particular, be or constitute the wall thickness control of the blow molding machine.
[0041] The present disclosure further relates to a blow molding machine with an extrusion head configured to dispense a melt tube that can be expanded in a blow mold to form a product from the melt tube. The blow mold can be an integral part of the blow molding machine, be associated with the blow molding machine at least temporarily, or be an external component. The blow molding machine further comprises a wall thickness control configured to adjust the dispensed melt tube according to a target tube wall thickness, in particular by performing at least one adjustment or profiling action. The wall thickness control obtains an actual tube wall thickness from a radar sensor that detects the wall thickness of a dispensed melt tube. The wall thickness control adjusts the target tube wall thickness based on the detected actual tube wall thickness.
[0042] The adjustment of a target tube wall thickness can be performed, on the one hand, for the melt tube currently being dispensed from the extrusion head (internal adjustment / internal profiling). Alternatively or additionally, and particularly preferably, the target tube wall thickness can be adjusted for a subsequent melt tube to be dispensed (subsequent adjustment / subsequent profiling). The present disclosure further relates to a blow mold with a cavity for receiving a melt tube and for forming a product from the melt tube by expansion and solidification of the melt. According to the present invention, the blow mold includes a radar sensor that detects the actual tube wall thickness of an inserted melt tube and / or the actual product wall thickness of the product formed in the cavity.The radar sensor is preferably connectable or connected to the wall thickness control of a blow molding machine according to the present disclosure.
[0043] All wall thickness measurements according to the present disclosure can be performed by the same radar sensor or by different and, in particular, separate sensors, and furthermore, in particular, separate radar sensors. In particular, a hose thickness radar sensor and a separate product thickness radar sensor can be provided. Alternatively, at least one common radar sensor can be used, which can be used, or is used, for measuring the actual hose wall thickness on the one hand and the actual product wall thickness on the other.
[0044] Further advantageous embodiments of the invention are specified in the dependent claims, the following description, and the accompanying drawings. The invention is illustrated by way of example and schematically in the drawings. These show:
[0045] Figure 1: a schematic representation of a blow molding machine, a blow mold and a manufactured product;
[0046] Figure 2: an enlarged representation of an extrusion head with possible arrangement positions of a radar sensor relative to a melt tube.
[0047] Figure 1 shows an example of a blow molding machine 1 with an extrusion head 2. The blow molding machine and the extrusion head can be designed as desired. The extrusion head is designed and configured to dispense a melt tube 3. The melt tube 3 consists in particular of at least one thermoplastic material, and more specifically, at least one thermoplastic polymer.
[0048] The extrusion head 3 can be configured as an accumulator head. It can have a melt chamber 11 in which a polymer melt is iteratively introduced and stored. During the discharge of the melt from the melt chamber 11, the melt tube 3 can be formed, particularly until the melt chamber 11 is emptied.
[0049] Alternatively, the extrusion head can be designed for the continuous or semi-continuous output of a melt tube and, in particular, can be designed without a melt chamber 11.
[0050] The blow molding machine 1 comprises at least one melt feed through which a thermoplastic and molten material is fed to the extrusion head 2. Preferably, the blow molding machine 1 comprises at least two and, in particular, three melt feeds through which, in particular, at least two different materials are fed. The two or more materials can be combined in several layers in the extrusion head 2 and, in particular, in the melt chamber 11. The extrusion head 2 can preferably be configured to dispense a multi-layer melt tube 3, in particular a two-layer or three-layer melt tube 3.
[0051] At least one radar sensor R, R1, R2, R3 is provided. The radar sensor can be a component of the blow molding machine 1 and / or the blow mold 5. Alternatively or additionally, a radar sensor R, R2 can be provided separately.
[0052] The blow molding machine 1 includes a wall thickness control 4. The wall thickness control 4 may include a data processing unit or be formed by a data processing unit. The wall thickness control 4 may be combined with or integrated into a plant control system of the blow molding machine 1.
[0053] The wall thickness control 4 is connected to at least one radar sensor R, R1 , R2, R3.
[0054] At least one manipulator M, M' can be provided to assist or bring about a relative movement between a radar sensor R, R1 , R2, R3 and a melting tube 3 and / or a product 6 and / or a blow mold 5.
[0055] The at least one manipulator M, M' can be configured in any way. A first example shown in Figure 1 provides that a manipulator M is configured as a multi-axis robot, in particular as an industrial robot. The robot can move at least one radar sensor R, R1 and / or a blow mold 5 and / or a product 6.
[0056] A second example, sketched in Figure 1, provides that a manipulator M' is formed by a single- or multi-axis motion device. The motion device can move, on the one hand, a radar sensor R, R3 and / or, on the other hand, a product 6 and / or a blow mold 5. In the example shown, the multi-axis motion device comprises, on the one hand, a rotary device by which a product 6 and / or a blow mold 5 can be rotated about an axis, in particular a vertical axis. Alternatively or additionally, the motion device comprises a slide guide by which a radar sensor R, R2 can be moved in at least one direction relative to the product 6 and / or a blow mold 5.
[0057] A preferred embodiment provides that, in the wall thickness control method, an assignment of at least one section of the dispensed melt tube 3 to a section of the product formed from the melt tube 3 is determined, in particular by a simulation. Alternatively or additionally, it can be provided that an assignment of at least one section of the dispensed melt tube 3 to a section of the product 6 formed from the melt tube 3 is monitored, in particular by a thickness measurement during an expansion of the melt tube in the cavity 10 of the blow mold 5. In the simulation and / or monitoring of the assignment, section-specific strains and / or thickness changes can be determined. The determination of the assignment can also be carried out with separate measurements of the actual tube wall thickness DSI and the actual product wall thickness DPI.
[0058] Within the scope of the present disclosure, it may suffice that only either the actual hose wall thickness DSI or the actual product wall thickness DPI is detected by a radar sensor R. Preferably, both wall thicknesses DSI and DPI are detected by at least one radar sensor R.
[0059] The adjustment of the target hose wall thickness DSS is preferably based on a plurality of recorded values of the actual hose wall thickness DSI and / or the actual product wall thickness DPI. The adjustment of the target hose wall thickness DSS is further preferably carried out by a control system and / or by a learning control system, in particular by a learning module.
[0060] The learning control system can be configured in any way desired. In particular, the learning control system, and especially the AI module, can comprise at least one neural network.
[0061] The learning controller can preferably detect a correlation between, on the one hand, several values of an actual tube wall thickness and an actual product wall thickness. These several values can relate to a plurality of sections of the melt loop 3 and the product 6 formed from this melt loop. Furthermore, the several values can relate to a plurality of melt loops 3 and products 6 formed from them, particularly those output sequentially.
[0062] The learning control system can be specifically trained to learn how to derive corresponding values of an actual product wall thickness from the one or more values of an actual tube wall thickness on the product 6, which is formed from the melt tube 3.
[0063] Alternatively or additionally, a learning control system is preferably trained to learn how one or more measures for adjusting the output of the melt tube affect it, in particular in the generation of at least one recorded value of the actual tube wall thickness DSI and / or the actual product wall thickness DPI.
[0064] The learning controller can further be preferably trained to learn how one or more measures for adjusting the output of the melt tube 3 affect it depending on at least one material used and / or a melting temperature. An actual tube wall thickness DSI and / or an actual product wall thickness DPI can be determined at any relative position of radar sensor R, R1, R2 and melt tube 3 or product 6, respectively.
[0065] According to a preferred embodiment, the actual tube wall thickness DSI is detected while a radar sensor R, R1, R2 is located inside the melt tube 3. The radar sensor R, R1 can be arranged, in particular, in an output direction of the melt tube 3 downstream of the extrusion head 2, and especially downstream of a mandrel section 7 of the extrusion head 2.
[0066] The detection of an actual product wall thickness DPI can preferably be carried out while a radar sensor R, R1 , R2 is located inside the formed product 6, and in particular inside the blow mold 5.
[0067] In particular, it is possible that a radar sensor R, R1 is initially arranged downstream of the extrusion head 2 during the discharge of the melt tube 3. Subsequently, the same or a different radar sensor R, R1 can be moved into or arranged in a blow mold 5.
[0068] Alternatively or additionally, an actual tube wall thickness DSI and / or an actual product wall thickness DPI can be detected while at least one radar sensor R, R1 , R2 is located outside the melt tube 3 and / or outside the formed product 6.
[0069] Measuring the wall thickness with a radar sensor located inside the melt tube 3 and / or the product 6 can facilitate particularly fast and comprehensive wall thickness measurement, especially for a large number of sections of the melt tube 3 or the product 6, and furthermore, especially for full-surface measurement of the wall thickness on the melt tube 3 and / or the product 6. Measuring the wall thickness with a radar sensor located outside the melt tube 3 and / or the product 6 can be advantageous if the product 6 to be manufactured has no or only very small openings through which a radar sensor R can be removed, or if the melt tube 3 has a small diameter.
[0070] In a preferred embodiment, a target hose wall thickness is defined as a hose thickness profile. In particular, a target hose wall thickness DSS can be specified differently for at least two sections of the melt hose 3 to be dispensed, and furthermore, in particular, differently for at least two sections in the circumferential direction of the melt hose 3, so that a circumferential thickness profile is specified, and / or differently for at least two sections in the longitudinal direction of the melt hose 3, so that a longitudinal thickness profile is specified. The specification of a circumferential thickness profile and / or a longitudinal thickness profile is preferably carried out such that a plurality of measured values of the actual hose wall thickness at sections of the product 6 correspond to the specified target wall thickness in a permissible manner.
[0071] The at least one radar sensor R, R1, R2 is preferably movable. It can be rotatable about at least one axis, in particular about an axis that runs parallel to the output direction of the melt tube 3. The axis can in particular be a central axis of the melt tube 3 or a central axis of the extrusion head 2. The at least one radar sensor is further preferably movable in a controlled manner. The movement can be effected in any desired way. On the one hand, the blow molding machine 1 and in particular the extrusion head 2 can comprise at least one actuator for moving a radar sensor R, R1, R2. Alternatively or additionally, the at least one radar sensor R, R1, R2 can be movable in a controlled manner by a manipulator M, M'. The manipulator M, M' can be an integral part of the blow molding machine 1 or be an external component.The blow molding machine 1, and in particular the wall thickness control 4, is preferably configured to specify a movement, in particular a controlled movement, of the at least one radar sensor R, R1, R2. The blow molding machine 1, and in particular the wall thickness control, is preferably connected to the at least one manipulator M, M' and / or a movement device via interference detection.
[0072] According to a preferred embodiment, the at least one radar sensor R, R1 , R2 is provided and configured to separately detect the actual hose wall thickness DSI for at least two material layers of the melt hose 3, and / or to separately detect the actual product wall thickness DPI for at least two material layers of the product 6.
[0073] Material-layer-specific wall thickness measurement can be performed simultaneously or in separate measurement steps. It can be performed as an alternative to, or in addition to, the measurement of the total thickness.
[0074] The blow molding machine 1 according to the present disclosure, and in particular a wall thickness control 4, is preferably configured to perform all the steps described above, individually or in combination, for the wall thickness control method. Alternatively, the wall thickness control method according to the present disclosure may preferably include all features, individually or in combination, disclosed for the blow molding machine 1, the wall thickness control 4, and / or the blow mold.
[0075] The blow molding machine 1, and in particular the wall thickness control 4, preferably obtains an actual product wall thickness DPI from a radar sensor R, R2, which detects the wall thickness of the product 6. This can be done in addition to obtaining an actual tube wall thickness DSI. The detection of the actual product wall thickness DPI can further relate, in particular, to the product 6 formed from the dispensed melt tube 3 for which an actual tube wall thickness DSI has already been detected. The blow molding machine 1 can preferably include at least one radar sensor R, R1, R2, which is used jointly for detecting the actual tube wall thickness and for detecting the actual product wall thickness.
[0076] Alternatively or additionally, the blow molding machine 1 can include at least one first radar sensor R1 for detecting the actual tube wall thickness DSI and at least one further radar sensor R2, R3 for detecting the actual product wall thickness DPI.
[0077] The wall thickness control 4 can preferably output at least one control value to a manipulator M, M'. This can be done in particular to
[0078] ■ to specify at least one relative movement between a radar sensor R, R1, R2 and the melting tube 3; and / or
[0079] ■ to specify at least one relative movement between a radar sensor R, R1, R2 and the product 6, in particular the product 6 formed from the melt tube 3; and / or
[0080] ■ to specify at least one relative movement between a radar sensor R, R1 , R2 and a blow mold 5 in which the melt tube 3 is expanded or has expanded.
[0081] The blow molding machine 1 can include a statically arranged radar sensor and / or a radar sensor that is only rotatable, in particular rotatable about a longitudinal axis of the melt tube 3. The at least one radar sensor R can be arranged one or more times inside or outside the melt tube 3.
[0082] Alternatively or additionally, the blow molding machine can include a radar sensor R, R1, R2, R3, which is movable and controlled by a manipulator M, M'. Various modifications of the invention are possible. In particular, all features disclosed for the embodiments can be combined or substituted for one another in any way.
[0083] A radar sensor R, in particular a hose thickness radar sensor, can be attached to or below the extrusion head. A radar sensor R, in particular a product thickness radar sensor, can be arranged or attached to a measuring table or in a measuring cell.
[0084] The actual wall thickness of the tube can preferably be measured at several longitudinal sections and, in particular, over the entire length of a dispensed melt tube. The actual wall thickness of the tube can preferably be measured at several circumferential sections, in particular over the entire circumference of the melt tube.
[0085] The setting of the target tube wall thickness (DSS) is preferably based on recorded values from two measurement cycles for the same batch of material, in particular on the one hand the recorded actual tube wall thickness (DSI) of the melt tube, and on the other hand the recorded actual product wall thickness (DPI) of the product that is formed from this melt tube.
[0086] The target tube wall thickness (DSS) is preferably set based on values recorded from two measurement cycles for different material batches, in particular, on the one hand, a recorded actual tube wall thickness (DSI) of a melt tube, and on the other hand, the recorded actual product wall thickness (DPI) of a product formed from another melt tube, in particular from the preceding melt tube.
[0087] 1 blow molding machine
[0088] 2 extrusion heads
[0089] 3 melt hose (issued)
[0090] 4 Wall thickness control
[0091] 5 blow mold
[0092] 6 products
[0093] 7 Thorn section / Thorn body
[0094] 8 Nozzle section / nozzle body
[0095] 9 blowpipe
[0096] 10 Cavity
[0097] 11 Melting chamber
[0098] DSS target hose wall thickness
[0099] DSI Actual Hose Wall Thickness
[0100] DPI Actual Product Wall Thickness
[0101] R radar sensor
[0102] R1 First radar sensor / hose thickness radar sensor R2 Additional radar sensor / product thickness radar sensor R3 Additional radar sensor
[0103] M Manipulator
[0104] M' Manipulator
Claims
Claims 1. Wall thickness control method for controlling the wall thickness of a melt tube (3) on a blow molding machine (1) with an extrusion head (2), a wall thickness control (4) and at least one blow mold (5), wherein the blow molding machine (1) outputs a melt tube (3) from the extrusion head (2) for the production of a product, and wherein the wall thickness control (4) adjusts the output of the melt tube (3) according to a target tube wall thickness (DSS), characterized in that the method comprises the following steps: Determining the actual wall thickness (DSI) of the dispensed melt tube (3) using a radar sensor (R, R1); Adjusting the target hose wall thickness (DSS), especially for the next melt hose to be issued, based on the recorded actual hose wall thickness (DSI).
2. Wall thickness control method according to claim 1, further comprising the steps: Determining the actual product wall thickness (DPI) of a product (6), in particular the product (6) that is formed or is formed from the dispensed melt tube (3), in particular by means of a radar sensor (R, R2); Adjusting the target tube wall thickness (DSS), especially for an additional melt tube to be dispensed, based on the recorded actual product wall thickness (DPI).
3. Wall thickness control method according to claim 2, wherein the actual hose wall thickness (DSI) is recorded for a plurality of sections of the melt hose (3), in particular as a two- or three-dimensional hose wall thickness profile; AND / OR the actual product wall thickness (DPI) is recorded for a plurality of sections of the formed product (3), in particular as a two- or three-dimensional product wall thickness profile.
4. Wall thickness control method according to claim 2 or 3, wherein an assignment of at least one section of the dispensed melt tube (3) to a section of the product (6) formed from the melt tube (3) is determined, in particular by a simulation.
5. Wall thickness control method according to one of the preceding claims, wherein the adjustment of the target hose wall thickness (DSS), in particular on the basis of a plurality of recorded values of the actual hose wall thickness (DSI) and / or the actual product wall thickness (DPI), is carried out. Through a regulation; AND / OR Through a learning control system, in particular through a learning module.
6. Wall thickness control method according to one of the preceding claims, wherein an actual hose wall thickness (DSI) and / or an actual product wall thickness (DPI) is detected while the radar sensor (R, R1, R2) is located within the melt tube (3), in particular in the discharge direction of the melt tube (3) downstream to the mandrel section (7) of the extrusion head (2); AND / OR is located within the formed product (6), in particular within the blow mold (5).
7. Wall thickness control method according to one of the preceding claims, wherein a target hose wall thickness is defined as a hose thickness profile, in particular wherein a target hose wall thickness (DSS) is specified differently for at least two sections of the melt hose (3) to be dispensed, in particular differently for at least two sections in the circumferential direction of the melt hose, so that a circumferential thickness profile is specified, and / or differently for at least two sections in the longitudinal direction of the melt hose (3), so that a longitudinal thickness profile is specified.
8. Wall thickness control method according to one of the preceding claims, wherein the at least one radar sensor (R, R1 , R2) is movable, in particular movable in a controlled manner, furthermore in particular movable by means of a manipulator (M, M'); AND / OR as a common radar sensor used on the one hand for detecting the actual hose wall thickness (DSI) and on the other hand for detecting the actual product wall thickness (DPI), in particular used alternately.
9. Wall thickness control method according to one of the preceding claims, wherein the at least one radar sensor (R, R1 , R2) the actual tube wall thickness (DSI) for at least two material layers of the melt tube (3) is recorded separately; AND / OR the actual product wall thickness (DPI) is recorded separately for at least two material layers of the product (6).
10. Software product comprising instructions which, when executed on a data processing device, are configured to execute a wall thickness control method according to any of the preceding claims.
11. Blow molding machine comprising an extrusion head (2) configured to dispense a melt tube (3) which is expandable in a blow mold (5) to form a product (6) from the melt tube (3), wherein the blow molding machine (1) further comprises a wall thickness control (4) configured to adjust the dispensing of the melt tube (3) according to a target tube wall thickness (DSS), characterized in that the wall thickness control obtains an actual tube wall thickness (DSI) from a radar sensor (R, R1, R2) which detects the wall thickness of a dispensed melt tube (3), and that the wall thickness control (4) adjusts the target tube wall thickness (DSS) based on the detected actual tube wall thickness (DSI), in particular the target tube wall thickness (DSS) for a further dispensed melt tube.
12. Blow molding machine according to the preceding claim, wherein the wall thickness control (4) further obtains an actual product wall thickness (DPI) from a sensor, preferably from a radar sensor (R, R2), wherein the sensor detects a wall thickness of a product (6), in particular of the product (6) formed from the dispensed melt tube (3), and wherein, in particular, the wall thickness control (4) further adjusts the target wall thickness (DSS) based on the detected actual product wall thickness (DPI), in particular for a next melt tube to be dispensed.
13. Blow molding machine according to any one of the preceding claims, wherein the blow molding machine (1) and, in particular, the wall thickness control (4) is configured to perform a wall thickness control method according to any one of the preceding claims.
14. Blow molding machine according to one of the preceding claims, wherein the blow molding machine (1) comprises at least one radar sensor (R, R1 , R2), in particular At least one radar sensor (R) shared for measuring the actual hose wall thickness and the actual product wall thickness; OR At least one first radar sensor (R1) for detecting the actual hose wall thickness (DSI) and at least one further radar sensor (R2) for detecting the actual product wall thickness (DPI).
15. Blow molding machine according to one of the preceding claims, wherein the blow molding machine (1), in particular the wall thickness control (4), is configured to output a control specification to at least one manipulator (M, M') in order to To specify at least one relative movement between a radar sensor (R, R1, R2) and the melting tube (3); AND / OR To specify at least one relative motion between a radar sensor (R, R1, R2) and the product (6) formed from the melt tube (3); AND / OR 16. Blow molding machine according to one of the preceding claims, wherein a radar sensor (R, R1, R2) is movable in a controlled manner by a manipulator (M, M').
17. Blow molding machine according to one of the preceding claims, wherein the at least one radar sensor (R, R1, R2) is arranged at least temporarily in the output direction of the melt tube (3) downstream of the extrusion head (2), in particular Within the melt tube (3), further in particular downstream to a mandrel section (7) of the extrusion head (2); OR Outside the melt tube (3).
18. Blow molding machine according to one of the preceding claims, wherein the at least one radar sensor (R, R1, R2) is arranged at least temporarily within a blow mold (5), in particular within the expanding or expanded melt tube (3).
19. Blow molding machine according to one of the preceding claims, wherein the at least one radar sensor (R, R1, R2) the actual tube wall thickness (DSI) for a plurality of sections of the melt tube (3) is recorded, in particular as a two- or three-dimensional tube wall thickness profile; AND / OR the actual product wall thickness (DPI) for a plurality of sections of the formed product (3) is recorded, in particular as a two- or three-dimensional product wall thickness profile.
20. Blow mold with a cavity (10) for receiving a melt tube (3) and for shaping a product (6) from the melt tube by expansion and solidification of the melt, characterized in that the blow mold (5) comprises a radar sensor (R, R3) which detects an actual tube wall thickness (DSI) of an inserted melt tube (3) and / or an actual product wall thickness (DPI) of the product (6) formed in the cavity (10).