Thermoforming Packaging Machine and Method for Controlling Film Punch

Abstract

This invention relates to a thermoforming packaging machine comprising a forming station, a filling path, a sealing station, a chain guide, a transverse cutting device, a longitudinal cutting device, and a control device. The transverse cutting device includes a film punch, an adjustment driver controllable by the control device to open and close the film punch, and a detection unit connected to the control device. The detection unit has at least one sensor for detecting the force progression occurring during the opening and closing of the film punch in each processing cycle. The control device is configured to dynamically adapt control signals for opening and / or closing the film punch in each processing cycle, wherein cutting of the film strip by means of the blade of the film punch can be detected as a result of the temporary force drop. The invention also relates to a method for controlled cutting of the film strip.

Description

Technical Field

[0001] This invention relates to a thermoforming packaging machine. It also relates to a method for controlling a film punch. Background Technology

[0002] A general-purpose thermoforming packaging machine is known from EP 3 109 017 B1. In this machine, a previously known film punch for cutting the film is calibrated between an open and closed position by means of a cylinder. During the associated force process, there is a sudden drop in force that causes the film cutting, as indicated in the force diagram. Nevertheless, the cylinder continues to build pressure until the pressure bar of the film punch presses against the blade of the film punch with a preset maximum force before the punching process is completed and the cylinder pressure is released. However, the repeated operation of the film punch to the preset maximum force level in each punching cycle results in high wear on the blade.

[0003] As an alternative to the above-described implementation, EP 3 109 017 B1 proposes a variation of the servo motor-controlled cutting method, which, compared to the pneumatic implementation, results in less stress on the film punch blade in each cutting cycle. To this end, the servo motor always moves the pressure bar to a preset working position corresponding to a specific position of the servo motor. The working position can be calibrated weekly, daily, or at each machine start-up of the thermoforming packaging machine by moving the pressure bar to contact the blade when the film is not present and storing the detectable angle used for this on the output shaft of the servo motor in the control system. However, this increases the calibration workload, especially since the film punch must be readjusted when changing the film. Summary of the Invention

[0004] The purpose of this invention is to provide a thermoforming packaging machine and a method for controlling a film punch, which is more efficient in operation than solutions used in the prior art, and most importantly, results in a shorter manufacturing cycle and reduced wear on the components used on the film punch.

[0005] This objective is achieved by a thermoforming packaging machine having the following characteristics. Furthermore, this objective is achieved by a method having the following characteristics.

[0006] The present invention relates to a thermoforming packaging machine having a forming station for thermoforming grooves in a film strip, a filling path for filling products into the grooves, a sealing station for sealing the grooves, a chain guide for guiding the film strip via a conveyor chain, a transverse cutting device for cutting through the film strip in a direction transverse to the conveying direction, a longitudinal cutting device for cutting through the film strip in the conveying direction, and a control device for controlling the processing performed on the thermoforming packaging machine.

[0007] The transverse cutting device includes a membrane punch, an adjustment drive that can be controlled by a control device to open and close the membrane punch, and a detection unit connected to the control device and having at least one sensor configured to detect the force process occurring at the membrane punch during the opening and closing of each processing cycle.

[0008] The intermittent thermoforming packaging machine is characterized in that the control device is designed to dynamically adapt control signals for opening and / or closing the film punch during each processing cycle of the film punch, when the force tends to increase in the force process, by means of a temporary slump in force detected by a sensor. With the help of this temporary slump in force, the cutting of the film strip by the blade of the film punch can be determined.

[0009] Compared to the preset operating position (where the film punch moves to the preset operating position in each processing cycle) according to the prior art, and compared to the preset maximum cutting force (where the film punch operates using the preset maximum cutting force in each processing cycle) according to the prior art, in this invention, a signal detected based on a force drop during the force process is used in each processing cycle to dynamically adapt the control signal of the control device to the opening and / or closing of the film punch. Therefore, during the operation of the thermoforming packaging machine, the force process can be automatically optimized for each processing cycle of the film punch, resulting in more precise operation of the film punch and less wear.

[0010] Because the control signal of the control device is automatically adjusted with respect to the detected penetration event of the film in each processing cycle (i.e., in each cutting process), the optimal operating mode of the film punch can be adjusted in a self-controlled manner on the thermoforming packaging machine. In this invention, compared with previously known methods with predetermined working positions or maximum cutting forces, the film punch operates dynamically with respect to film cutting in each processing cycle; that is, the subsequent force progression of opening and / or closing the film punch can be adapted accordingly in each processing cycle based on the detectable film cutting time.

[0011] Dynamic adaptation of the control signal can, for example, come from the following facts: by detecting membrane perforation, the control is adapted to slow down the stroke speed of the membrane punch, abruptly or with a delay stop the membrane punch from closing before it is fully closed, increase the control force after membrane perforation is detected until the membrane punch is opened using a temporary rate of force change smaller than the rate of force change detected before membrane perforation, and / or generate a start signal based on a sudden drop in force (especially in real time), thereby triggering the opening of the membrane punch with or without a delay.

[0012] One variation provides a sensor comprising a measuring base and at least one strain gauge attached to the measuring base. This can be used to detect force processes, particularly to detect sudden force drops that occur when a membrane is cut, using simple, inexpensive construction components.

[0013] Preferably, the measuring seat is positioned to be pushed onto the vertical pull rod of the film punch. This allows the measuring seat to be attached to the film punch in a cost-effective manner and to be well integrated into the force flow of the film punch. Such a measuring seat can also be easily retrofitted to a delivered film punch (i.e., remounted to a delivered thermoforming packaging machine). For its measuring applications, the measuring seat can be configured onto the pull rod with a simple procedure.

[0014] One advantageous variation for measurement purposes is that, with the diaphragm punch in the open position, the measuring seat is pre-tightened to the pull rod by means of a (screw) nut. This pre-tightening can be released at least until the membrane is cut by actuating the diaphragm pressure cutter (i.e., when the diaphragm punch is closed), as the force tends to increase during the force progression, which can be detected by means of a strain gauge. The pre-tightening of the measuring seat allows the strain gauge attached to the measuring seat to detect changes in the force progression of the diaphragm punch particularly quickly.

[0015] Preferably, the tie rod includes a threaded portion for securing the nut. The threaded portion may have fine threads. This allows for particularly precise setting of the nut's preload. Furthermore, due to the increased self-locking property of the fine threads, better measurement results can be obtained over multiple processing cycles.

[0016] According to one embodiment, the compression of the measuring seat along the pull rod by means of the nut is greater than the longitudinal extension of the pull rod that occurs during the operation of the diaphragm punch. This allows the force progression when the diaphragm is pressed against the blade to be detected by means of the resulting longitudinal elongation of the measuring seat.

[0017] If the strain gauge is constructed as a semiconductor strain gauge and / or a rosette strain gauge, the sensor technology used in the membrane punch can be improved. This allows for more precise detection of force progression, and most importantly, more precise detection of force drop progression (i.e., membrane cutting) in real time, enabling the control signals of the control system to dynamically adapt in a fast-response manner to optimize the opening and / or closing of the membrane punch for each processing cycle.

[0018] Preferably, the strain gauge is disposed on the inner circumference of the measuring seat. In this variation, the measuring seat can be considered as the housing of the strain gauge and as a protection against undesirable influences such as moisture. To improve the hygienic operation of the diaphragm punch, the measuring seat can be made of stainless steel.

[0019] Preferably, when the film punch is closed, the film strip moves out of its conveying plane and is pressed against the blade. This allows for additional tension on the film strip, which can speed up the cutting process and result in better cut edges on the packaging material.

[0020] If the blade is mounted in a fixed position, the membrane punch is particularly stable. The adjustment drive can be a servo motor configured to adjust the pressure bar of the membrane punch. When the membrane punch is closed, the pressure bar presses the membrane strip against the blade located above it from below. As the membrane strip is cut, the pressure bar and the blade come into contact with each other, which typically results in a sudden drop in force during the measured force process.

[0021] Advantageously, the control device has a controller configured to dynamically adapt to the control current of the servo motor used as a control signal for opening and / or closing the membrane punch in a transverse cutting device. Therefore, the angle of the servo motor's output shaft can be approached based on the membrane strip cutting detected in each processing cycle, the angle being dynamically generated in response to the membrane strip cutting, wherein the servo motor's retraction (i.e., the opening of the membrane punch) preferably occurs simultaneously with reaching the adjusted angle or has an adjustable delay.

[0022] It is conceivable that the dynamic adaptation of the control signals used to open and / or close the membrane punch depends on the predetermined amount of force drop reached and / or on the delay following the detection of the force drop. Therefore, interfering variables in the force process can be filtered out.

[0023] A preferred variation provides a control device configured to determine the thickness of the membrane strip to be cut based on the detected force progression. This can be achieved by detecting the position of the pressure bar when the membrane strip is absent, with the membrane punch in the closed state, and comparing that position with the position of the pressure bar when the membrane is present, as the force tends to increase during the force progression. It is conceivable that the operating parameters of the transverse cutting device and / or the longitudinal cutting device can be automatically adjusted based on the detected thickness.

[0024] It is conceivable that the detected nominal force of the cut film strip can be used to dynamically adapt the control signals for controlling the operation of the downstream longitudinal cutting device. This enables the transverse and longitudinal cutting devices to interact collaboratively, thereby precisely separating the packages along the thermoforming packaging machine.

[0025] The control device can be configured to determine the degree of blade wear based on the start time detected during the force process, the detected force used for cutting, and / or the amount of temporary force drop. The degree of wear can preferably be visually displayed on a display device mounted on the thermoforming packaging machine. It is conceivable that the display device be directly mounted on the film punch. In this context, it is conceivable that the maintenance or upkeep interval of the film punch blade can be automatically indicated.

[0026] One embodiment provides a thermoforming packaging machine having a display and / or control device capable of visualizing the force progression of the film punch, configured to generate a control algorithm based on detected force progression and / or based on several detected force progressions. The display may be part of a display device, and therefore preferably part of an operation panel available in the area of ​​the sealing station.

[0027] It is conceivable that the control device is configured to correct the control algorithm based on detected data from the film punch and / or other workstations of the thermoforming packaging machine that have been executed since the machine’s startup when the thermoforming packaging machine is turned off or when the operation of the thermoforming packaging machine is terminated. The purpose is to update the control algorithm available on the control device when the thermoforming packaging machine is restarted.

[0028] The present invention also relates to a method for detecting the cutting of a film strip in a thermoforming packaging machine, the cutting being performed by means of a film punch of a transverse cutting device disposed on the thermoforming packaging machine. For this purpose, in each processing cycle of the film punch, the force process caused by the opening and closing of the film punch is detected at least segmentally at the transverse cutting device by means of at least one sensor.

[0029] The method according to the invention is characterized in that, in response to a temporary drop in force detected by means of a sensor during a period when the force tends to increase in the force process, the control device of the thermoforming packaging machine performs dynamic adaptation to the control signal for opening and / or closing the film punch in each processing cycle of the film punch, wherein the cutting of the film strip by means of the blade of the film punch is detected as a result of the temporary drop in force.

[0030] Therefore, because thermoforming packaging machines (especially film punches) react dynamically to the cutting of the film strip in a self-controlled manner, the operation of the film punch can be optimally adapted for each processing cycle. This significantly reduces the amount of calibration required and at least slows down the wear of the blades used on the film punch.

[0031] Dynamic adaptation can be performed on control signals, for example, the control system slows down the stroke speed for closing the membrane punch due to the detection of membrane perforation, suddenly or with a delay stops closing the membrane punch before it is fully closed, the control force is increased after the detection of membrane perforation until the membrane punch is opened using a temporary force change rate smaller than the force change rate detected before membrane perforation, and / or a start signal is generated based on a sudden drop in force, particularly in real time, thereby triggering the opening of the membrane punch with or without a delay.

[0032] According to an embodiment of the invention, the sensor measures the force progression of each processing cycle of the membrane punch by means of at least one strain gauge in the force flow disposed on a preload measuring seat. The measuring seat is mounted on a vertical tie rod of the membrane punch under preload (i.e., with compressive load) by means of a nut, such that the measuring seat, mounted in a compressed manner, also expands according to the extension of the tie rod when the membrane strip is cut. As a result, the force progression of each processing cycle of the membrane punch can be accurately determined by means of the strain gauge attached to the measuring seat.

[0033] Preferably, the temporary drop in force approximates a triangular process, which allows for reliable detection of sudden punching of the membrane strip. The triangular process, or a similar sudden process, can trigger an adjustment of the control signal, allowing the membrane punch to open simultaneously or with a certain delay. Attached Figure Description

[0034] The embodiments of the present invention will now be explained in more detail with reference to the accompanying drawings. Wherein:

[0035] Figure 1 A thermoforming packaging machine is shown in 3D view;

[0036] Figure 2a A transverse cutting device in the form of a film punch of a thermoforming packaging machine is shown in the open position;

[0037] Figure 2b The closed position is shown. Figure 2a Horizontal cutting device;

[0038] Figure 3 A membrane punch with a measuring seat and an enlarged portion thereof are shown;

[0039] Figure 4 The measuring stand with strain gauges is shown in a separate view;

[0040] Figure 5a A diagram showing the positional displacement of the adjustable pressure bar of the membrane punch during the cutting process is shown; and

[0041] Figure 5b The force progression that can be detected at the membrane punch during the processing cycle is shown. Detailed Implementation

[0042] In all the accompanying drawings, the same parts are given the same reference numerals.

[0043] Figure 1A perspective view of an intermittently operating thermoforming packaging machine 1 according to the present invention is shown. The thermoforming packaging machine 1 has a forming station 2, a sealing station 3, a transverse cutting device 4, and a longitudinal cutting device 5 arranged sequentially along the conveying direction R on a frame 6. On the input side, a feed roller 7 is located on the frame 6, from which the lower film 8 is drawn out. Furthermore, the thermoforming packaging machine 1 has a conveyor chain 11 that holds the lower film 8 in each major operating cycle and further conveys the lower film 8 along the conveying direction R.

[0044] In the illustrated embodiment, forming station 2 is configured as a thermoforming station, in which grooves are formed in the lower film 8 by thermoforming, for example, by means of compressed air or vacuum. Forming station 2 can be configured such that several grooves are formed adjacent to each other in a direction perpendicular to the conveying direction R.

[0045] A filling path 12 is provided downstream of the conveying direction R of the forming station 2, in which the product is used to fill the groove formed in the lower film 8.

[0046] The sealing station 3 includes a hermetically sealable chamber 3a, wherein, for example, before sealing with an upper membrane 10 dispensed from the upper membrane receiver 9, the atmosphere in the tank can be purged and / or replaced by an exchange gas or gas mixture.

[0047] The transverse cutting device 4 includes a membrane punch 15 (see reference). Figure 2a The membrane punch 15 cuts the lower membrane 8 and upper membrane 10 (hereinafter also referred to as membrane belts 8 and 10) between adjacent slots in a direction transverse to the conveying direction R. In this context, the transverse cutting device 4 is operated such that the lower membrane 8 is not separated over its entire width, but is not cut through at least in the edge region. This allows for controlled forward conveying via the conveyor chain 11.

[0048] The longitudinal cutting device 5 can be configured as a blade configuration, which cuts the lower film 8 and the upper film 10 along the conveying direction R between adjacent slots and at the side edge of the lower film 8, so that the separated package appears downstream of the longitudinal cutting device 5.

[0049] The left and right conveyor chains 11 of the thermoforming packaging machine 1, which hold the lower film 8 on both sides, are guided in chain guides 13. The chain guides 13 are protected from external influences by side plates 14 of the thermoforming packaging machine 1, and the chain guides 13 are attached to the side plates 14 if necessary. The side plates 14 may be metal plates.

[0050] The thermoforming packaging machine 1 also includes a control device 19, which has the task of controlling and monitoring the processes performed in the thermoforming packaging machine 1. A display device 20 with operating elements 21 is provided for the operator to visualize or is used by the operator to influence the processing sequence in the thermoforming packaging machine 1.

[0051] Figure 2a The membrane punch 15 of the transverse cutting device 4 is shown. Figure 2a In the middle, the diaphragm punch 15 is in the open position. Figure 2a A schematic diagram illustrates a control device 19 functionally connected to an adjustment driver 16 of a diaphragm punch 15. The adjustment driver 16 is configured to open and close the diaphragm punch 15 and may include a servo motor. Furthermore, the diaphragm punch 15 includes a detection unit 17 functionally connected to the control device 19 and includes a sensor 18 configured to detect the force progression K (see reference) occurring at the diaphragm punch 15 during the opening and closing phase of each processing cycle. Figure 5b ).

[0052] The diaphragm punch 15 has a mounting surface such as Figure 2a The knife 22 is shown in a fixed position. Furthermore, the diaphragm punch 15 has... Figure 2a An adjustable pressure bar 30 is configured in the lowered position. The height of the adjustable pressure bar 30 is adjusted by means of the adjustment driver 16, so as to press against the stationary blade 22 from below during the processing cycle for cutting the membrane belts 8, 10.

[0053] exist Figure 2b In this configuration, the blade 22 and the pressure rod 30 are arranged to contact each other. Therefore, the diaphragm punch 15... Figure 2b The membrane strips 8 and 10 are in the closed position. With the membrane strips 8 and 10 clamped between the blade and the pressure bar, the force progress K can be detected by means of the sensor 18 of the detection unit 17, and the force progress K can be forwarded to the control device 19. Based on the force progress K, the adjustment driver 16 of the membrane punch 15 can be dynamically controlled by adapting the control signal x.

[0054] Figure 3 An enlarged view of the membrane punch 15 is shown, particularly the enlarged portion of the detection unit 17. The detection unit 17 (particularly the sensor 18) is configured as a measuring seat 23. The measuring seat 23 is pushed onto a vertical pull rod 24. According to... Figure 3 The measuring seat 23 is pre-tightened onto the pull rod 24 by means of a nut 25. The pull rod 24 has a threaded portion 31 for tightening the nut and for setting the preload on the measuring seat 23.

[0055] During the stamping process, when the pressure rod 30 presses against the die 22 from below, the pull rod 24 extends, causing the support 26 formed on the pull rod 24 for the measuring seat 23 to move downward in the y-direction, thereby causing the measuring seat 23 located on the pull rod 24 to extend in the y-direction. The expansion of the measuring seat 23 due to the tensile stress of the pull rod can be detected by means of a strain gauge 27 attached to the measuring seat. This is in Figure 3 The magnified portion of C is shown. Figure 3In the magnified portion C, the measuring seat 23 has a corresponding strain gauge 27 on its inner side 28 (see also...). Figure 4 The strain gauge 27 measures the force progression K during the processing cycle of the membrane punch 15 (i.e., particularly during the punching process in which the pressure bar 23 presses the membrane strips 8, 10 against the knife 22 located above the pressure bar 23 from below).

[0056] Figure 4 Sensor 18 is shown in a separate view. Measuring base 23 is constructed as a short tube and has opposing strain gauges 27 on its inner side 28. At measuring base 23, strain gauges 27 are switched by means of a full-bridge (bridge circuit) to detect the force progression K during the processing cycle of diaphragm punch 15.

[0057] On the diaphragm punch 15, a measuring seat 23, mounted on and pre-tightened on the pull rod 24, forms a cost-effective component for detecting the force progression K. Calibration of the measuring seat 23 can be performed simply by adjusting the preload using a nut 25. Since the measuring seat 23 is positioned on the pull rod 24, the effects of temperature and / or bending variations in the pull rod 24 are substantially compensated. The strain gauges 27 are also well protected from external influences by the measuring seat 23 surrounding them, and the strain gauges 27 can be easily replaced.

[0058] Figure 5a The positional displacement P of the pressure bar 30 during the processing cycle D of the membrane punch 15 is shown. Figure 5b The corresponding force process K is shown.

[0059] When the membrane punch 15 opens at the start time t1 of processing cycle D, the pressure rod 30 is in the position... Figure 2a The location shown.

[0060] At time t2, pressure rod 30 and blade 22 clamp membrane strips 8 and 10 between them. When pressure rod 30 presses membrane strips 8 and 10 against blade 22 located above it from below, membrane strips 8 and 10 are cut, as shown by the sudden drop in force E at cutting time t3. Figure 5b In the force process K shown, the force in force process K tends to increase and then suddenly decreases. This means that the membrane strips 8 and 10 are completely cut and the pressure rod 30 comes into contact with the blade 22.

[0061] Figure 5bThe diagram schematically illustrates the force progression K (particularly the determined force drop E) detected by the control device 19 and determined by the detection device 17. The control device 19 is configured to dynamically adapt the control signal x in response to the opening of the membrane punch 15. In particular, the controller 35 of the control device 19 can be used for control signal adaptation. The control of the regulating driver 16 (particularly the servo motor 36) of the membrane punch 15 is adjusted according to the control signal x, which is redefined time and again for each processing cycle D, so as to control the cutting pressure lever 30 with 8 and 10 as detected.

[0062] according to Figure 5b The sudden drop in force E has a triangular process V. The triangular process V and / or the amount B, which is the skewness of the sudden drop in force E, can exist as a prerequisite for the dynamic adaptation of the control signal x.

[0063] In response to the cutting of membrane strips 8 and 10, control device 19 can adapt control signal x to adjustment driver 16 so that until time t4, blade 22 and pressure rod 30 are further pressed together in a contact state. The duration of time interval t3-t4 can be variably set at control device 19.

[0064] Starting at time t4, the diaphragm punch 15 opens (i.e., the pressure rod 30 moves back to the open position), causing the measured force to decrease from time t4 to time t5. Starting at time t5, the pressure rod 30 and the blade 22 are no longer in contact.

[0065] It can be inferred that during the time interval t3-t4, when the increase in force is reached, the time t4 can be determined, and the control signal x can be dynamically adjusted accordingly.

[0066] Figure 5a and Figure 5b The diagram illustrates the detection of the initiation of penetration of membrane strips 8 and 10 by a sudden, temporary drop in force E during the force process K. This allows the membrane punch 15 to be shut off in each processing cycle D until penetration of membrane strips 8 and 10 is detected. Furthermore, unnecessary overload of the knife 22 can be avoided by shutting off the membrane punch 15 until penetration of membrane strips 8 and 10 is detected or after a slight delay.

[0067] Based on the aforementioned force process K, the presence of film strips 8 and 10 in the film punch 15 can be detected by evaluating characteristic points (such as the impact of pressure rod 30 on film strips 8 and 10 at time t2 and the departure of pressure rod 30 from knife 22 at time t5). If film strips 8 and 10 are present, i.e., positions M (impact of pressure rod 30 on film strips 8 and 10) and N (departure from the lower edge of knife) are different, where these detection values ​​M and N are the same in the case of missing film. When the absence of film strips 8 and 10 is detected, an emergency stop function can be triggered on the thermoforming packaging machine 1.

Claims

1. A thermoforming packaging machine (1) having a forming station (2) for thermoforming pockets in a film web (8, 10), a filling path (12) for filling products into the pockets, a sealing station (3) for sealing the pockets, a chain guide (13) for guiding the film web (8, 10) with a conveyor chain (11), a transverse cutting device (4) for cutting the film web (8, 10) in a direction transverse to the conveying direction (R), a longitudinal cutting device (5) for cutting the film web (8, 10) in the conveying direction (R), and a control device (19) for controlling the processes carried out on the thermoforming packaging machine (1), wherein the transverse cutting device (4) comprises a film punch (15), an adjustment drive (16) controllable by means of the control device (19) to open and close the film punch (15), and a detection unit (17) connected to the control device (19), the detection unit (17) having at least one sensor (18) configured to detect a force progression (K) during opening and closing at the film punch (15) in each process cycle (D), characterized in that the control device (19) is configured to perform a dynamic adaptation of a control signal (x) for opening and / or closing the film punch (15) in each process cycle (D) of the film punch (15) as a function of a force temporary drop (E) detected by means of the sensor (18) during a force tendency to increase (Z) of the force progression (K), wherein a cutting of the film web (8, 10) by means of a knife (22) of the film punch (15) can be detected as a result of the force temporary drop (E), wherein the sensor (18) comprises a measuring seat (23) and at least one strain gauge (27) attached to the measuring seat (23), wherein the measuring seat (23) is pushed onto a vertical pull rod (24) of the film punch (15).

2. The thermoforming packaging machine according to claim 1, characterized in that, The measuring seat (23) is pre-tensioned on the pull rod (24) by means of a nut (25).

3. The thermoforming packaging machine according to claim 2, characterized in that, The compression of the measuring seat (23) along the pull rod (24) by means of the nut (25) is greater than the longitudinal extension of the pull rod (24) occurring during operation of the film punch (15).

4. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The strain gauge (27) is configured as a semiconductor strain gauge and / or a rosette strain gauge.

5. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The strain gauge (27) is arranged on an inner circumference (28) of the measuring seat (23).

6. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The film web (8, 10) is moved out of a conveying plane of the film web in the direction of the knife (22) when the film punch (15) is closed.

7. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The control device (19) comprises a controller (35) configured to adapt a control current of a servo motor (36) of the transverse cutting device (4) for opening and / or closing the film punch (15) as a control signal (x).

8. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The control device (19) is configured to determine the thickness of the film web (8, 10) to be cut based on the detected force progression (K).

9. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The control device (19) is configured to determine the degree of wear of the knife (22) based on the start time (t3) and / or the amount (B) of the force temporary drop (E) detected in the force progression (K).

10. The thermoforming packaging machine according to any one of claims 1 to 3, characterized in that, The thermoforming packaging machine (1) has a display device (20) on which the force progression (K) of the film punch (15) can be visualized and / or the control device (19) is configured to generate a control algorithm based on the detected force progression (K).

11. A method on a thermoforming packaging machine (1) for detecting a cut of a film web (8, 10) by means of a film punch (15) of a transverse cutting device (4) arranged on the thermoforming packaging machine (1), wherein a force progression (K) caused by opening and closing of the film punch (15) is detected at least section-wise on the transverse cutting device (4) by means of at least one sensor (18) per processing cycle (D) of the film punch (15), characterized in that The control device (19) of the thermoforming packaging machine (1) performs a dynamic adaptation of the control signal (x) for opening and / or closing the film punch (15) per processing cycle (D) of the film punch (15) in response to a force temporary drop (E) detected by means of the sensor (18) during a force tendency to increase (Z) in the force progression (K), wherein a cut into the film web (8, 10) by means of a knife (22) of the film punch (15) as a result of the force temporary drop (E) is indicated, wherein the sensor (18) measures the force progression (K) by means of at least one strain gauge (27) attached to a pre-tensioned measuring seat (23), wherein the measuring seat (23) is pushed onto a vertical pull rod (24) of the film punch (15).

12. The method of claim 11, wherein, The force temporary drop (E) has the shape of an approximately triangular progression (V).

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