PACKAGING MACHINE WITHOUT DANCERS

Description

[0001] The present invention relates to a packaging machine that unwinds a bottom material web from a supply roll and transports it intermittently along the packaging machine. In a forming station, the bottom material web is optionally formed into packaging cavities, which are then covered / filled with a packaged product. Subsequently, a top material web is sealed to the bottom material web in a sealing station. The bottom and top material webs are each unwound from a supply roll, and at least one supply roll is motor-driven. Furthermore, the present invention relates to a method for producing packaging.

[0002] Such packaging machines are known from the prior art, for example from US 3 979 877 A. In these packaging machines, a base material web is unwound from a supply roll and intermittently transported along the packaging machine. In a forming station, a packaging trough is first formed into the base material web, if necessary, which is then filled with a packaged product, in particular a food product, or the unformed base material web is covered with a packaged product. The packaging trough is then closed in a sealing station with a top material web, which is sealed to the base material web. The top material web is also unwound from a supply roll. A dancer is provided between the supply roll and the sealing station, which must be adapted to the advancement of the base material web during advancement.

[0003] For example, WO 2012 / 116823 discloses such packaging machines in which a base material web is unwound from a supply roll and preferably transported intermittently along the packaging machine. In a forming station, a packaging trough is first formed into the base material web, which is then filled with a packaged product, in particular a food product. The packaging trough is then closed in a sealing station with a top material web, which is sealed to the base material web. The material web is also unwound from a supply roll. A dancer is provided between the supply roll and the sealing station, which must be adapted to the advance made by the base material web during a feed. In the past, this required a dancer individually designed for each packaging machine, which proved to be very complex.In addition, the web tension was subject to inherent fluctuations, which could be disadvantageous. The unwinding movement of the film was primarily generated by the feed of the packaging machine and the tension force in the film generated by the dancer.

[0004] WO 2016087169 A1 teaches an improved embodiment with a rotary dancer, wherein the upper material web is unwound from a supply roll and a dancer is provided downstream of the supply roll, which preferably has two rollers which are provided on a rod which rotates about a rotational axis driven by a rotary drive and thereby stores a certain length of material web and / or generates a desired tension in the material web.

[0005] This state-of-the-art technology has the disadvantage that the respective material web is significantly stretched, causing it to become damaged and / or warped. Furthermore, the sealed connections between the upper material web and the lower material web are often damaged during further transport, especially at the beginning of the transport process.

[0006] It was therefore the object of the present invention to provide a packaging machine and a method which do not have the disadvantages of the prior art.

[0007] The problem is solved with a packaging machine according to claim 1.

[0008] The statements made regarding this subject matter of the present invention apply equally to the other subject matters of the present invention, and vice versa. Features disclosed regarding this subject matter of the present invention may be incorporated into the other subject matters.

[0009] The present invention relates to a packaging machine in which a base material web, in particular a plastic material web, paper and / or cardboard material web and / or a combination of paper and / or cardboard material web and plastic material web, which preferably has a width of between 200 mm and 1 m or more, is unwound from a supply roll and transported intermittently / cyclically along the packaging machine, with each cycle advancing by a specific amount. For this purpose, a transport means is provided, for example two chains with a plurality of grippers, which reversibly grasp the base material web at both edges and transport it along the packaging machine. In a forming station, if present, this base material web is then first heated and, if necessary, packaging troughs are formed into the base material web by means of a deep-drawing tool.Typically, several packaging trays arranged in a so-called format are formed simultaneously and then transported along the packaging machine simultaneously. The size of the format, in particular its length in the transport direction of the product web, determines the length of the pre-drawn section. Each packaging tray is then filled with a packaged product, in particular a food product such as sausage, ham or cheese, or the non-deep-drawn product web is covered with a packaged product and, in a next step, sealed with an upper material web in a sealing station, whereby the upper material web is usually sealed to the lower material web. Those skilled in the art will understand that the packaged product can also be filled / placed in unformed product webs. The finished packaging is then separated. The upper material web is also unrolled from a supply roll.

[0010] The number of packages produced simultaneously and their length or width determine the length of the feed in one cycle, with up to 3 meters being quite common.

[0011] According to the invention, at least one, preferably both, supply roll(s) are driven by a motor whose parameters, in particular speed and / or torque, can be adjusted based on the parameters of the respective supply roll.

[0012] For example, the core diameter of the roll, the film width, the film thickness, the film length, the original and / or current weight of the supply roll, the original and / or current diameter of the supply roll, and / or the specific film weight are taken into account. Based on one or more of these parameters for the respective supply roll, the currently required torque or rotational speed is calculated, and the motor is controlled / regulated accordingly, in particular to provide the film length required for one cycle / feed. The motor drive is preferably a torque motor capable of providing such a high torque that the desired speed of the supply roll is always achieved.

[0013] Furthermore, according to the invention, it has now been found that it is advantageous to dispense with a dancer. This makes it possible to reduce the masses that must be accelerated by the material web, whereby the tensile force in the material web can be further reduced. In the area of ​​the upper material web and / or lower material web, a film brake, for example for aligning print marks, as disclosed, for example, in EP1339609A1, can be dispensed with. A roller brake, as disclosed, for example, in WO2004077913A2, can also be dispensed with, since the motor itself also generates the braking effect, whereby the usual and unwanted abrasion caused by a previous roller brake is eliminated. Very thin films can be processed with the packaging machine according to the invention.

[0014] The packaging machine preferably has a means for detecting the speed of the respective material web, in particular the base material web, preferably the speed profile during a feed / advance movement, and / or calculating the speed profile. Alternatively or additionally, the speed or speed profile can be stored as data and / or a data set in a control system of the packaging machine. The speed or speed profile is preferably taken into account when controlling / regulating the drive motor of the respective supply roll.

[0015] The motor is preferably a servo motor or a torque motor. The motor preferably has a means, for example an incremental encoder, with which the rotational position of the motor's output shaft can be detected. The motor is preferably a direct motor, i.e., a motor that is connected in a rotationally fixed or torsionally rigid manner to the shaft on which the respective supply roll is mounted. Alternatively, a rigid connection, for example, a toothed belt, is provided between the motor and the shaft on which the supply roll is mounted.

[0016] A torque motor is a servo motor optimized for high torque. Torque motors are typically built as brushless DC motors. However, switched reluctance motors are sometimes also referred to as torque motors.

[0017] Torque motors are either external rotor (stator inside, rotor ("rotor") outside) or internal rotor (rotor inside, stator outside). External rotors are preferred for torque motors because, due to the relationships shown below, they provide greater torque for the same size. The high drive torque of torque motors enables high accelerations and leads to high system dynamics. Torque motors have greater drive rigidity than conventional motor-gearbox units and preferably no backlash. This results in better control characteristics due to reduced disturbances and increased repeatability. High torques are required for large supply roll diameters, and high speeds are required for small supply roll diameters to drive the film roll at the preferred speed of the packaging machine. Both can be achieved with a servo and / or torque motor.

[0018] According to a preferred embodiment of the present invention, the shaft on which the supply roll is provided in a rotationally fixed manner is mounted at both ends, for example in order to minimize deformation / shaft deflection or its disruptive consequences and / or to form it symmetrically.

[0019] According to the invention, the drive of the transport means and the drive of the supply roll are at least temporarily synchronized during a feed such that the transport means and the material web move at least substantially at the same speed.

[0020] In this aspect of the present invention, the drive of the transport means for the base material web, in particular the two chains, and the drive of the supply roll(s) are synchronized, in particular by means of a control system, such that the speed profile of the transport means and the speed profile of the material web are at least temporarily identical during a pre-drawing process when the material web is pulled off the roll. This results in only minimal inertia-related forces in the material web. Preferably, the speeds / speed profiles are constant throughout the entire pre-drawing process.

[0021] According to another preferred embodiment, the speed of the material web at the beginning of a feed is higher than the speed of the transport means.

[0022] When synchronizing the speed of the material web and the transport device, an elongation / shortening of the transport device is preferably taken into account. This elongation / shortening of the transport device can be achieved, for example, using strain gauges or a non-contact, particularly optical or electromagnetic, method. The signal from this sensor is used to control the drive of the transport device and / or the supply roll.

[0023] When synchronizing the speed of the material web and the transport means, the reaction time(s) of individual components are preferably taken into account, for example the reaction time(s) of the control system, the drive, for example a drive, in particular a drive motor, and / or the mechanical component(s) of the drive, for example the transport means. Reaction times can arise, for example, from signal transmission delays and / or component inertia and / or slippage. These reaction times can be determined by calculation, for example based on empirical values ​​and / or manufacturer specifications and / or approximate calculations, and / or in tests directly after completion, maintenance, and / or general overhaul of the packaging machine.A reaction time preferably indicates the time difference between the start of a command in a line of the control code, which is intended, for example, to causally initiate the movement of a component, such as the supply roll, until the start of the movement of the component itself. Reaction times are preferably taken into account by starting the movements of the supply roll and the transport means at different times, with the time offset preferably corresponding at least to the difference between the reaction times for the start of the supply roll and the transport means. The reaction time of the transport means is dimensioned such that it includes the time until the start of the movement of the material web at the last sealed seam produced.In this way, the movements of the material web at the position of the last created sealing seam connecting the upper and lower material webs and the supply roll can start, preferably substantially, synchronously.

[0024] According to another preferred embodiment, the speed of the upper and / or lower material web at the end of a pull and / or at the start of the pull and / or during the entire pull is lower than the speed of the transport means that transports the lower material web, wherein the preferred time for reducing the speed depends, for example, on the material properties of the upper and / or lower material web; for example, particularly stretchable or shrinkable and / or thin films are preferably subjected to the speed reduction rather late in order to minimize the unwanted constriction in the transverse direction as a result of the desired longitudinal stretch.

[0025] For example, areas of upper material webs printed with a printed image and intended as lids for the packaging tray are typically manufactured minimally shorter than the nominal dimension, and to date, according to the prior art, for example WO2004096645A1, are stretched or extended using a film brake immediately before sealing so that each printed image or each lid is essentially congruent with the corresponding packaging tray and, in particular, no offset or overlap with adjacent packaging trays occurs or builds up across one or more packs. Preferably, the speed of the material web, in this case the upper material web, is now selected to be lower than the speed of the transport means of the lower material web, preferably at the end of a feed, so that, for example, at the end of a feed, the material web lags behind the transport means.This can be achieved, for example, by rotating the drive of the supply roll of the face material web somewhat slower relative to the transport means, whereby the material web, in this case the face material web, is elastically and / or plastically stretched, preferably essentially between its discharge point from the supply roll and the sealing seam of the previous pre-roll, until the length of the printed image and / or lid area essentially corresponds to the corresponding length of the packaging tray(s) or pre-roll. After this, the face material web can be sealed to the packaging tray(s). An additional film brake can be omitted.

[0026] Alternatively, the speed of the upper and / or lower material web is selected to be lower than the speed of the transport means of the lower material web, at the latest at the end of a feed, by means of a film brake that grips and decelerates the material web, thereby achieving the desired target stretch. Stretching the material web using a film brake is preferred over stretching by driving the supply roll when the force required to generate the required target stretch is high, for example, when the material web is rather stiff and / or thick, requiring a drive with a disproportionately high torque.

[0027] Preferably, the number of deflection rollers provided downstream of the supply roll is preferably a maximum of two, particularly preferably a maximum of one and most preferably none at all.

[0028] Preferably, the drives of the lower material web and the upper material web are functionally connected to one another in such a way that they can be controlled to drive the respective material web synchronously or asynchronously. For example, the drive of the upper material web roll receives information about the rotational movement and / or the control of the drive of the lower material web and / or vice versa. This information can include the rotational path, the rotational speed, and / or the acceleration, particularly during a cycle.

[0029] A further inventive or preferred subject of the present invention is therefore a packaging machine in which the material web is guided parallel to the transport plane of the transport means, in particular horizontally, without deflection after unwinding from the supply roll.

[0030] The statements made regarding this subject matter of the present invention apply equally to the other subject matters of the present invention, and vice versa. Features disclosed regarding this subject matter of the present invention may be incorporated into the other subject matters.

[0031] Preferably, the supply roll is provided so that it is height-adjustable on the packaging machine and during operation of the packaging machine. This allows the material web to be guided parallel to the transport plane of the transport means, in particular horizontally, without deflection after unwinding from the supply roll, despite a reduction in the diameter of the supply roll.

[0032] According to the invention or preferably, the transport means is driven between the sealing station and / or the insertion station and the sealing station and / or in the region of the sealing station and / or downstream of the sealing station.

[0033] The statements made regarding this subject matter of the present invention apply equally to the other subject matters of the present invention, and vice versa. Features disclosed regarding this subject matter of the present invention may be incorporated into the other subject matters.

[0034] Such a drive in the area of ​​the sealing station reduces the elongation / shortening of the transport means, in particular the chain, which is relevant for the synchronization of the speed of the transport means and the speed of the material web, thus minimizing inaccuracies.

[0035] According to the invention, the packaging machine has at least one sensor that measures the elongation and / or the web tension and / or the web force of the respective material web, in particular the upper material web. The signal from this sensor is preferably used to control the drive of the transport means of the lower material web and / or the supply roll of the upper and / or lower material web. For example, as soon as the elongation force in the respective material web exceeds a certain value and / or the increase in the elongation force is too great, the rotational speed for unwinding the supply roll of the upper and / or lower material web is increased and / or the speed of the transport means at which the lower material web is transported along the packaging machine is reduced, thereby reducing the web force / web tension in the upper and / or lower material web.Alternatively or additionally, if the stretching of the upper material web is required, for example, for precise placement of the upper material web on the lower material web, the rotation of the supply roll of the upper material web can be changed, in particular reduced, and / or the speed of the transport means of the lower material web can be increased to achieve greater stretch in the upper material web. The sensor signal can be used to detect fluctuations in the web tension, which can arise, for example, from an out-of-round supply roll and / or deflection roll and / or winding errors in the supply roll, and compensate for them if necessary.

[0036] Preferably, the sensor is a means that detects the torque of the drive motor that drives the supply roll of the respective material web, and / or a measuring roller that measures, for example, an average value of the web tension of the respective material web and / or the web force at various measuring points, preferably with spatial resolution, and / or the sensor is a measuring bearing on at least one deflection roller(s). However, the sensor is preferably a non-contact sensor that is based, for example, on deflecting the material web with an air stream and determining the local path deviations, for example with an optical sensor, and / or according to the principle of dynamic pressure measurement.

[0037] The length of the upper material web between the supply roll and the rear end of the sealing seam of the previous pre-roll, relative to the transport direction of the material webs, is preferably short and / or corresponds at least to the length of a packaging tray or a pre-roll, but particularly preferably to a multiple of the length of a packaging tray or a pre-roll. This length is also preferably adjustable.

[0038] The object is also achieved with a method for producing packaging with a packaging machine which unwinds a base material web from a supply roll and transports it intermittently by means of a transport means along the packaging machine and in the process forms packaging troughs in the base material web in a forming station, wherein the base material web is then covered / filled with a packaged item, wherein an upper material web is subsequently sealed to the base material web in a sealing station, wherein the base and upper material webs are each unrolled from a supply roll and the supply roll is unrolled by means of a motor and the drive of the supply roll is at least temporarily synchronized during a feed such that the transport means and the material web move at least substantially at the same speed.

[0039] The statements made regarding this subject matter of the present invention apply equally to the other subject matters of the present invention, and vice versa. Features disclosed regarding this subject matter of the present invention may be incorporated into the other subject matters.

[0040] Preferably, at the beginning of a feed, the unwinding of the upper and / or lower material webs is ahead of the speed of the transport means of the lower material web. This can at least reduce the increased force in the respective material web caused by the mass inertia of the respective material web.

[0041] Preferably, at the end of a pre-roll, the unwinding of the upper and / or lower material web follows the speed of the transport means of the lower material web. This allows stretching to be created in the respective material web, in particular the upper material web, for example, to correctly position the upper material web on the lower material web before sealing.

[0042] Preferably, the speed of the material web, preferably of the upper and / or lower material web and / or of the transport means of the lower material web, is controlled by means of a sensor which detects the elongation and / or web tension and / or web force of the respective material web.

[0043] In the following, the inventions are described on the basis of Figures 1 to 4 These explanations are merely exemplary and do not limit the general concept of the invention. The explanations apply equally to all subject matter of the present invention.

[0044] In the following, the invention is described with reference to Figures 1 to 9 These explanations are merely exemplary and do not limit the general concept of the invention. The explanations apply equally to all subject matter of the present invention. Figure 1 shows the packaging machine according to the invention. Figures 2 - 4 each show an embodiment of an upper material web unwinding without dancer. Figures 5 and 6 each show an embodiment of a top material web unwinding with a printer. Figure 7 shows the force-time curve in a material web during a pull. Figures 8 and 9 each show an embodiment of a bottom material web unwinding without dancer.

[0045] Figure 1shows the packaging machine 1 according to the invention, which has a thermoforming station 2, a filling station 7 and a sealing station 15. A base material web 8, here a plastic web 8, is pulled off a supply roll 22 and transported in cycles along the packaging machine according to the invention from right to left. In each cycle, the base material web 8 is transported further by one format length / feed length. For this purpose, the packaging machine has two transport means (not shown here), in this case two endless chains each, which are arranged to the right and left of the base material web 8. Both at the beginning and at the end of the packaging machine, at least one gearwheel is provided for each chain, around which the respective chain is deflected. At least one of these gearwheels is driven. The gearwheels in the input area and / or in the output area can be connected to one another, preferably by a rigid shaft.Each transport means has a plurality of clamping means, each of which clamps the bottom material web 8 at its edge in the inlet area 19 and transfers the movement of the transport means to the bottom material web 8. In the outlet area of ​​the packaging machine, the clamped connection between the transport means and the bottom material web 8 is released again. Downstream of the inlet area 19, a heating means 13 can be provided, which heats the material web 8, particularly when it is stationary. In the thermoforming station 2, which has an upper tool 3 and a lower tool 4 that has the shape of the packaging tray to be produced, the packaging trays 6 can be formed into the heated material web 8. The lower tool 4 is arranged on a lifting table 5, which, as symbolized by the double arrow, is vertically adjustable. Before each film feed, the lower tool 4 is lowered and then raised again.As the packaging machine continues, the packaging troughs are then filled with the packaging material 16 in the filling station 7. The person skilled in the art will recognize that the formation of packaging troughs in the lower material web can also be omitted. In the subsequent sealing station 15, which also consists of an upper tool 12 and a vertically adjustable lower tool 11, an upper material web 14 is firmly attached to the lower material web 8 by sealing. This transfers the movement of the lower material web 8 to the upper material web 14. In the sealing station, the upper tool and / or the lower tool are also lowered or raised before and after each material web transport. The upper material web 14, in particular a plastic film, can also be guided in transport means or transported by transport chains, whereby these transport means then extend only in front of the sealing station and, if necessary, downstream.Otherwise, the statements made regarding the means of transport of the lower material web apply. The upper material web can also be heated with a heating medium and deep-drawn. For sealing, a heatable sealing frame is provided as the lower tool 11, for example, which has an opening for each packaging cavity into which the packaging cavity dips during sealing, i.e. during the upward movement of the lower sealing tool. For sealing, the upper and lower material webs are pressed together between the upper and lower tools 12, 11 and bond under the influence of heat and pressure. After sealing, the tools 11, 12 are moved apart vertically again. According to the invention, no dancer is provided between the supply roll 21 and the sealing tool. The person skilled in the art will understand that several upper material webs can be present, for example in a multi-layer pack or a pack with several upper material webs.Preferably, no dancer is provided along the length of each upper material web. A person skilled in the art will further understand that a dancer is preferably not provided in the area of ​​the lower material web either. Before and / or during sealing of the upper material web to the lower material web, a gas exchange preferably takes place in each packaging tray. For this purpose, the air present in the packaging tray is first partially sucked out and then replaced with a replacement gas. For this purpose, holes are made in the lower material web in the area of ​​the transport chains in the area of ​​each format, through which the air between the material webs 8, 14 is sucked out and the replacement gas is then blown in. As the packaging machine continues, the finished packages are separated, which in the present case is carried out by the cross cutter 18 and the longitudinal cutter 17. In the present case, the cross cutter 18 can also be raised or lowered by a lifting device 9.lowerable.

[0046] According to the invention, at least one supply roll 21, 22 is driven by a motor, in particular a torque motor, and / or the material web is deflected so little that the length of the respectively required feed of the respective material web is unwound from the roll without the tensile force of the two transport means, the transport chains and / or the tensile force of the lower material web being significantly transferred to the upper material web and / or the lower material. As a result, the respective material web is only subjected to comparatively low tension and is therefore not pre-stretched and does not develop wrinkles. Even comparatively thin material webs can be processed using the packaging machine according to the invention and the method according to the invention. No film brake is required for the upper material web in order to adapt the position of the print marks on the upper material web to the position of the troughs in the lower material web.

[0047] Furthermore, according to the invention, it has now been found that it is advantageous to dispense with a dancer. This allows the masses that must be accelerated by the material web to be reduced, thereby further reducing the tensile force in the material web. In the area of ​​the upper material web and / or lower material web, a film brake, for example for aligning print marks, can be dispensed with. A roller brake can also be dispensed with, since the motor itself also generates the braking effect, thus eliminating the usual and unwanted abrasion caused by a previous roller brake. The packaging machine according to the invention can process very thin films.

[0048] Preferably, the drive of the transport means for the lower material web, in particular the two chains, and the drive of the supply roll(s) are synchronized, in particular by means of a control system, such that the speed profile of the transport means and the speed profile of the material web are identical, at least temporarily, during a pull-up. This results in only minimal inertia-related forces in the material web. Preferably, the speeds / speed profiles are constant throughout the entire pull-up.

[0049] Due to the low tensile force in the material web, especially at the beginning of the pull, the sealing seam produced in the last cycle is only slightly stressed and therefore not damaged.

[0050] Figure 2shows a first embodiment of an upper material unwinder without a dancer. The upper material web 14 is provided as a supply roll 21 on the driven shaft 23 in a rotationally fixed manner and is unrolled from this and then deflected around a roll 24 to then be introduced into the sealing station 15, in which it is materially bonded to the lower material web 8, so that material webs 8, 14 then move together. The roll 24 preferably has a very low mass inertia and / or an air cushion is provided between the roll 24 and the material web 14, which reduces the friction between the roll and the material web. The supply roll 21 is driven at least temporarily such that the material web 14 is unrolled at the same speed profile as the speed profile at which the conveyor moves along the packaging machine.

[0051] Figure 3 shows an embodiment according to Figure 2, whereby in the present case two supply rolls 21, each driven, are provided. One supply roll serves as a spare roll, so that only a very small production loss is guaranteed when changing rolls. However, the material webs 14 of both rolls are generally not guided around the roll 24 at the same time. Otherwise, please refer to the explanations for Figure 2 referred to.

[0052] Figure 4shows a design of a top material web unwinder that does not have a deflection roller 24. In this case, the material web 14 is fed directly into the sealing station 15. To achieve this, the material web roll 21 is provided on a height-adjustable, driven shaft 23 to ensure that the angle (here 0 degrees) at which the material web 14 enters the sealing station is always the same. The dashed line shows an advanced level of material web consumption, with the diameter of the roll having reduced accordingly. The height adjustment of the roll is represented by the double arrow 25, whereby when the top material web is unwinded during production, the shaft 23 is merely lowered. Only when the supply roll is used up is the shaft 23 raised to its original position.The adjustment of the shaft 23 is preferably carried out automatically, for example by measuring and / or calculating the diameter of the supply roll and adjusting the shaft 23 accordingly.

[0053] The Figures 5 and 6 each show an embodiment in which the upper material web 14 is printed either on one side or, as shown here, on both sides. For this purpose, a printer 26 is provided, which can print the upper material web 14 on one or both sides. Again, the rollers 24 are preferably provided such that they have either a certain mass inertia and / or very low friction between the deflection roller 24 and the material web. In the embodiment according to Figure 6 a more complicated printer is planned, which may require two rolls 24.

[0054] Figure 7shows the force-time curve in the bottom or top material web over the time course of a pre-pulling movement. Three examples are shown: a traditional unwinding system with a dancer, an improved unwinding system with a dancer, and the system according to the invention without a dancer. All curves show that at the beginning of the pre-pulling movement, marked "Start," a force peak develops, which has already been significantly reduced in the improved unwinding system compared to the traditional unwinding system with a dancer. In the unwinding system without a dancer and with preferably optimized or non-existent deflection rollers 24, this peak is generated solely by the mass inertia of the material web 8, 14. Due to the significantly reduced force in the material web 8, 14, damage to this web can be avoided, and vibrations in the material web are significantly reduced.At the same time, the seal seam of already sealed packages is significantly reduced. To further reduce or even completely eliminate the initial peak, it may be advantageous for the material web 8, 14 to precede the transport means at the beginning of a pre-feed, for example, by unwinding the material web before the conveyor starts and / or by initially unwinding the material web at a higher speed than the speed of the transport means.

[0055] The Figures 8 and 9 each show an embodiment of a bottom material web unwinding system. In the present case, the bottom material web 8 is unwound from a supply roll, which is also provided on a driven shaft, and is gripped by the grippers of the chain and transported further. Figures 8 and 9only the chain idler wheel 27 is shown. In the embodiment according to Figure 8 , the material web 8 is still deflected by the chain circulation 27, which in the embodiment according to Figure 9 is not the case. In the embodiment according to Figure 9 the shaft 23 on which the supply roll 22 of the base material web 8 is mounted must be as in the example according to Figure 4 , height can be adjusted. List of reference symbols:

[0056] 1 Packaging machine 2 Forming station, thermoforming station 3 Upper tool of the thermoforming station 4 Lower tool of the thermoforming station 5 Lifting table, support of a tool of the sealing, thermoforming station and / or the cutting device 6 Packaging tray 7 First filling station 8 Material web, lower material web, product web 9 Lifting device 10 Drive 11 Lower tool of the sealing station 12 Upper tool of the sealing station 13 Heating medium 14 Upper material web, lid film, product web 15 Sealing station 16 Packaged goods 17 Longitudinal cutter 18 Cross cutter 19 Infeed area 20- 21 Supply roll of the upper material web 22 Supply roll of the lower material web 23 Shaft / rotary drive of the supply roll 21 24 Roll 25 Height adjustment 26 Printer 27 Transport means, chain, chain circulation

Claims

1. Packaging machine (1), having supply rolls (21, 22), a drive for at least one of the supply rolls (21, 22), a transport means (27), a drive for the transport means (27), a forming station (2) and a sealing station (15), wherein a lower material web (8) unrolls from the supply roll (22) and is transported intermittently along the packaging machine by means of the driven transport means (27) and, in the process, in a forming station (2), optionally forms pack cavities (6) in the lower material web (8), which are then occupied by / filled with a packaged material (16), wherein subsequently in the sealing station (15) an upper material web (14) is sealed onto the lower material web (8), wherein the lower and the upper material web (8, 14) are each unrolled from the supply roll (21, 22) and at least one supply roll (21, 22) is driven by a motor, characterized in that the drive of the transport means (27) and the drive of the supply roll (21, 22), during drawing, are at least temporarily synchronized so that the transport means (27) and the material web (8, 14) move at least substantially at the same speed, wherein at the beginning of drawing the material web (8, 14) is ahead of the transport means and at the end of drawing the material web (8, 14) is behind the transport means, wherein said packaging machine has a sensor which measures the elongation and / or web tension and / or web force of the material web (8, 14).

2. Packaging machine according to Claim 1, characterized in that a lengthening / shortening of the transport means is taken into account during synchronization.

3. Packaging machine according to one of Claims 1 to 2, characterized in that response time(s) of individual components are taken into account during synchronization.

4. Packaging machine according to one of the preceding claims, characterized in that the material web (8, 14), upon unwinding from the supply roll, is carried without deflection, in particular horizontally, parallel to the transport plane of the transport means.

5. Packaging machine according to Claim 4, characterized in that the supply roll (21, 22) is provided so as to be height-adjustable on the packaging machine and during operation of the packaging machine.

6. Packaging machine according to one of the preceding claims, characterized in that the transport means is driven between the sealing station and / or the insertion station and the sealing station and / or in the region of the sealing station and / or downstream of the sealing station.

7. Packaging machine according to Claims 1 to 6, characterized in that the signal of the sensor is used for feedback control of the drive of the transport means and / or of the supply roll.

8. Method for producing an item of packaging using a packaging machine (1), which unrolls a lower material web (8) from a supply roll (52) and intermittently transports it along the packaging machine by means of a transport means (27) and, in the process, in a forming station (2) preferably forms pack cavities (6) in the lower material web (8), which are then occupied by / filled with a packaged material (16), wherein subsequently in a sealing station (15) an upper material web (14) is sealed onto the lower material web (8), wherein the lower and the upper material web (8, 14) are each unrolled from a supply roll (21, 22), characterized in that the supply roll (21, 22) is unrolled in a manner driven by a motor, and the drive of the supply roll (21, 22), during drawing, is at least temporarily synchronized so that the transport means (27) and the material web (8, 14) move at least substantially at the same speed, wherein at the beginning of drawing the unwinding of the material web (8, 14) is ahead of the speed of the transport means and at the end of drawing the unwinding of the material web (8, 14) is behind the speed of the transport means, wherein the speed of the material web (8, 14) and / or of the transport means (27) is subject to feedback control by means of a sensor which detects the elongation and / or web tension and / or web force of the material web (8, 14).