Patent Grant
11891202
The present invention relates to a packaging machine and to a method for producing a packaging.
Packaging machines of this type are known from the prior art. In these packaging machines, a bottom film web is unwound from a supply roll and conveyed, preferably intermittently, along the packaging machine. In a forming station, there is formed into the bottom film web a packaging cavity, which is subsequently filled with a product to be packaged, in particular a food product. After this, the packaging cavity is closed off in a sealing station with a top film, which is sealed to the bottom film. The film web is here likewise unwound from a supply roll. Between the supply roll and the sealing station is here provided a dancer roll, which has to be adapted to the initial draw which the bottom film web makes in one feed.
For instance, WO 2012/116823 discloses packaging machines in which a bottom film web is unwound from a supply roll and is conveyed, preferably intermittently, along the packaging machine. In a forming station there is firstly formed into the bottom film web a packaging cavity, which is subsequently filled with a product to be packaged, in particular a food product. After this, the packaging cavity is closed off in a sealing station with a top film, which is sealed to the bottom film. The film web is here likewise unwound from a supply roll. Between the supply roll and the sealing station is here provided a dancer roll, which has to be adapted to the initial draw which the bottom film web makes in one feed. For this, a dancer roll which was individually designed for the packaging machine had formerly to be provided, which proved to be very costly. Moreover, the material web tension was subject to inherent fluctuations, which could be detrimental. The unwinding motion of the films was preferably generated by the feed of the packaging machine and the tensioning force, generated by the dancer roll, in the film.
WO 2016087169 A1 teaches an improved version with rotational dancer roll, wherein the top film web is unwound from a supply roll, and downstream of the supply roll is provided a dancer roll which preferably has two rolls provided on a linkage that, driven by a rotary drive, rotates about a rotation axis and thereby stores a certain length of film web and/or generates a desired tension in the film web.
It was therefore the object of the present invention to provide a packaging machine having a dancer roll, and a method for producing a packaging, the range of application of which is markedly widened and/or tensions in the respective film web are markedly reduced.
The object is achieved with a packaging machine which unwinds a bottom film web from a supply roll and conveys it intermittently or continuously along the packaging machine and herein, in a forming station, forms into the bottom film web packaging cavities, which are then filled with a product to be packaged, wherein subsequently, in a sealing station, a top film web is sealed to the bottom film web, wherein the bottom and top film web are respectively unwound from a supply roll and the bottom and top film web are respectively tensioned by means of a dancer roll, wherein the supply roll is driven by means of a motor, the parameters of which, in particular rotation speed and/or torque, can be set on the basis of the parameters of the respective supply roll.
The comments made regarding this subject of the present invention apply equally to the other subjects of the present invention, and vice versa. Features which have been disclosed in relation to this subject of the present invention can be incorporated into the other subjects.
The present invention relates to a packaging machine in which a bottom film web, in particular a plastics film web, which preferably has a width between 200 mm and 1 m and more, is unwound from a supply roll and is conveyed, preferably intermittently/in cycles, along the packaging machine. In a forming station, this bottom film web is then firstly warmed and, by means of a deep-drawing tool, packaging cavities are formed into the bottom film web. Generally, a plurality of packaging cavities, which are arranged in a so-called format, are formed simultaneously and thereafter simultaneously conveyed along the packaging machine. After this, each packaging cavity is filled with a product to be packaged, in particular a food product, such as, for instance, sausage, ham or cheese, and in a next step, in a sealing station, closed off with a top film, wherein the top film is generally sealed to the bottom film web. The person skilled in the art will understand that the product to be packaged can also be filled/placed into unformed films. After this, the thus finished packaging is separated. The top film web is likewise unwound from a supply roll. In relation to the direction of transport of the respective film web, downstream of at least one supply roll is found a dancer roll, which keeps the tension in the film web at least substantially constant. The dancer roll can be constituted, for instance, by a linear or a rotational dancer roll or a pivot arm dancer roll.
The number of simultaneously produced packagings and the length or width thereof determine the length of the feed within a cycle, wherein up to 3 meters are perfectly normal.
According to the invention, at least one, preferably both, supply roll(s) are driven by means of a motor, the parameters of which, in particular rotation speed and/or torque, can be set on the basis of the parameters of the respective supply roll.
For instance, 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. On the basis of one or more of these parameters of the respective supply roll, the currently required torque or the required rotation speed is calculated and the motor is controlled/regulated accordingly, in particular in order to provide the film length required for a cycle/feed.
The packaging machine according to the invention has the advantage that very small but also very large feed lengths can be realized without the film being placed under heavy mechanical strain, for instance stretched. Feed lengths of just a few mm up to 3 meters or more can be realized without problems. The drive of the respective supply roll is preferably activated already from a feed of 0.1 mm and above. In the region of the top film and/or bottom film, a film brake, for instance for the alignment of print marks, can be dispensed with. A roll brake can also be dispensed with, since the motor itself also generates the braking effect, after which customary and unwanted abrasion produced by a previous roll brake is no longer an issue. With the packaging machine according to the invention, very thin films are able to be processed.
Preferably, the packaging machine has a means which registers the speed of the respective film web, in particular the bottom film web, preferably the speed pattern during an initial draw/feed. Alternatively or additionally, the speed or the speed pattern can be stored as data and/or a data record in a control system of the packaging machine. The speed and the speed pattern are preferably taken into account in the controlling/regulation of the drive motor of the respective supply roll.
Preferably, the motor is a servo motor or a torque motor. Preferably, the motor has a means, for instance an incremental encoder, with which the rotational position of the power take-off shaft of the motor can be registered. Preferably, the motor is a direct motor, i.e. a motor which is connected in a rotationally secure or torsion-proof manner to the shaft on which the respective supply roll is mounted. Alternatively, between the motor and the shaft on which the supply roll is mounted is provided a rigidly designed connection, for instance a toothed belt.
A torque motor is a servo motor optimized for high torques. Torque motors are usually constructed as brushless direct-current motors. Sometimes, switched reluctance motors are also, however, referred to as a torque motor.
Torque motors are external rotors (stator on the inside, rotor on the outside) or internal rotors (rotor on the inside, stator on the outside). In torque motors, external rotors are preferred, since, with these, due to the correlations represented below, a greater torque is available while the overall size remains the same. The large drive torque of torque motors allows large accelerations and leads to high dynamics of the system. Torque motors have a higher drive stiffness than traditional motor-gear units and, more preferably, no backlash. Hence better control characteristics are obtained by virtue of reduced disturbance variables and an increased repeat accuracy. In the case of large supply roll diameters, high torques, and in the case of small supply roll diameters, high rotation speeds, are required in order to drive the film roll in accordance with the initial draw speed of the packaging machine. Both can be realized with a servo and/or torque motor.
Preferably, the dancer roll, which is provided downstream of the respective supply roll, has a movement transducer, in particular a rotary encoder. The signal of this movement transducer is preferably used to regulate/control the motor. Alternatively or additionally, the signal of this movement transducer, in interaction with the incremental encoder of the drive motor of the respective supply roll, is used to determine the diameter of the supply roll, in particular the initial diameter after a change of supply roll. As a result, when the supply roll is changed, the diameter is determined automatically without having to be measured by a worker. This value is then taken into account when setting the parameters of the drive motor of the drive shaft of the supply roll. Preferably, during operation, in the course of, before or after each cycle, or after a specific number of cycles, the current diameter of the film roll is also determined and taken into account when setting of the parameters of the drives of the supply roll, in particular when setting the torque, the speed and/or the number of increments through which the drive shaft of the supply roll is meant to rotate. Preferably, the roll diameter is determined in respect of each initial draw/feed, wherein the regulation/control does not however take account of an updated value within each cycle, but more rarely, for instance only once every 3-7 cycles, and then, quite particularly preferably, forms a mean value from the measurements, for instance in order to avoid a miscalculation.
According to a preferred embodiment of the present invention, the shaft is supported at both ends, wherein a mounting is preferably provided pivotably, for instance pivotably about a vertical axis, in order to be able to easily perform a change of supply roll.
A further subject of the present invention is a packaging machine which unwinds a bottom film web from a supply roll and conveys it intermittently or continuously along the packaging machine and herein preferably, in a forming station, forms into the bottom film web packaging cavities, which are then filled with a product to be packaged, wherein subsequently, in a sealing station, a top film web is sealed to the bottom film web, wherein the bottom and top film web are respectively unwound from a supply roll and the supply roll is rotatably mounted on a shaft, wherein, as a result of the rotation, a film web is unwound in a running direction, and wherein the shaft is provided such that it is displaceable along its longitudinal center axis.
The comments made regarding this subject of the present invention apply equally to the other subjects of the present invention, and vice versa. Features which have been disclosed regarding this subject of the present invention can be incorporated into the other subjects.
Preferably, the shaft, during production, is longitudinally displaced, in particular in order to align an edge of the film web, for instance, relative to the frame of the packaging machine and/or to the film transport.
The shaft can be displaced relative to its mounting, and/or the mounting relative to the frame of the packaging machine.
Preferably, the adjustment of the shaft is realized by a servo drive.
Preferably, the shaft is driven by a motor, in particular a torque motor. This motor can be provided in fixed arrangement or can be jointly displaced as one with the shaft.
Should the motor be provided in fixed arrangement, a coupling, in particular a sliding coupling, is preferably provided between the shaft and the motor.
Preferably, the packaging machine has a sensor, which detects the position of the film web, for instance relative to the frame of the packaging machine or to the means of conveyance of the film web. For instance, the sensor is a web edge detection means.
Preferably, the sensor controls/regulates the servo drive, which longitudinally displaces the shaft.
In addition, the object is achieved with a method for producing a packaging with a packaging machine which unwinds a bottom film web from a supply roll and conveys it intermittently or continuously along the packaging machine and herein preferably, in a forming station, forms into the bottom film web packaging cavities, which are then filled with a product to be packaged, wherein subsequently, in a sealing station, a top film web is sealed to the bottom film web, and the bottom and top film web are respectively unwound from a supply roll and the bottom and top film web are respectively tensioned by means of a dancer roll, wherein the supply roll is unwound, driven by means of a motor.
The comments made regarding this subject of the present invention apply equally to the other subjects of the present invention, and vice versa. Features which have been disclosed in relation to this subject of the present invention can be incorporated into the other subjects.
In this subject of the present invention, the unwinding of the film web is realized at least substantially by means of a motor which drives the respective supply roll rotatively, and not, as in the prior art, by a movement of conveyor chains which convey the bottom film web along the packaging machine, or by means of the bottom film web to which the top film is sealed. Nor, according to the present invention, is a supporting of the unwinding movement sufficient. The motor preferably also acts as a brake in order to avoid an unwanted unwinding of the film web from the supply roll.
Preferably, the supply roll is unwound, at least substantially, in accordance with a feed rate of the bottom film web. For this, data concerning the initial draw length and/or the speed profile of the feed are available to a control system. The rotation speed of the supply roll is set accordingly. Since the drive of the supply roll is preferably a torque motor with a very large torque, the drive can accordingly also respond dynamically to an indexed drive.
Preferably, the parameters of the motor which drives the respective supply roll, in particular the rotation speed, the number of increments through which the power take-off shaft of the motor is intended to rotate, and/or the torque, are set on the basis of the parameters of the supply roll, in particular the weight and/or the diameter thereof, wherein preferably the respectively current weight or the respectively current diameter of the supply roll, which diameter changes upon the initial draw, is taken into account. Particularly preferably, at least when the film is changed, the diameter and/or weight of the supply roll is determined automatically or inputted into the control/regulating system of the packaging machine.
Preferably, the dancer roll has a movement transducer, in particular a rotary encoder. On the basis of the signal of the movement transducer and on the basis of the incremental encoder of the motor which drives the supply roll, the original or initial or current diameter of the film roll can be determined. Preferably, the signal of the movement transducer is used to regulate/control the motor, for instance in that the torque, the rotation speed and/or the turning length of the power take-off shaft of the motor which drives the supply roll is calculated and the motor controlled/regulated accordingly.
Preferably, at least during the automatic unwinding of the supply roll, a deviation of the actual position from the target position of the dancer roll system is registered and, from this, a correction value to the previously calculated unwinding speed/torque is determined and taken into account. As a result, in the event of an undesirably high deviation of the position of the dancer roll from the desired position, the drive of the supply roll can be accelerated or reduced in order that the dancer roll makes its way back into the desired target position.
Preferably, the nominal width of the films is inputted or read out automatically.
According to another preferred embodiment of the present invention, the original supply roll parameters are drawn from a database and/or a data carrier. For instance, in the database can be contained the film width, the supply roll weight, the supply roll diameter, the length of the film web, and/or the internal and/or external diameter of the core. The data can be arranged, for instance, on a data carrier disposed on the supply roll, for instance a transponder. The supply roll can also, however, have an identification means, for instance a barcode or QR code, on the basis of which the data can be retrieved from a database.
Preferably, on the basis of the parameters of the supply roll and/or a registered unwinding history, the residual length of the film web is determined. On the basis of this known residual length, the approaching film end can, for instance, be indicated to the operator and/or can initiate an automated film change.
A further subject of the present invention is a method in which a bottom film web unwinds from a supply roll and conveys intermittently or continuously along the packaging machine and herein, where appropriate, in a forming station, forms into the bottom film web packaging cavities, which are then filled with a product to be packaged, wherein subsequently, in a sealing station, a top film web is sealed to the bottom film web, wherein the bottom and top film web are respectively unwound from a supply roll and the supply roll is rotatably mounted on a shaft, wherein, as a result of the rotation, a film web is unwound in a running direction, and in which the shaft is displaced along its longitudinal center axis.
The comments made regarding this subject of the present invention apply equally to the other subjects of the present invention, and vice versa. Features which have been disclosed regarding this subject of the present invention can be incorporated into the other subjects.
The inventions are explained in greater detail below with reference to
According to the invention, at least one supply roll 21, 22 is driven by a motor, in particular a torque motor, such that the length of the respectively required feed of the respective film web is unwound from the roll without the tensile force of the two conveying means, of the conveyor chains, and/or the tensile force of the bottom film web, being significantly transmitted to the top film web. As a result, the respective film web is subjected only to a comparatively small tension and thus is not prestretched and does not crease. With the packaging machine according to the invention or with the method according to the invention, also comparatively thin film webs can be processed. No film brake for the top film web is required in order to adapt the position of the print marks on the top film to the position of the cavities in the bottom film web. The dancer roll must be designed only for very small movements or for a very small, or even no, film web storage volume.
Preferably, the rotation of the motor which drives the supply roll 21, 22 is controlled/regulated by a computer means, which can be part of the packaging machine or part of a linear control system. In particular, the rotation speed of the supply roll is controlled such that the unwound film web length corresponds to the feed, and/or such that the speed profile of the unwinding of the film web and/or of the feed of the conveying means, in particular of the conveyor chains, is at least substantially identical. The respectively current diameter or the respectively current weight of the supply roll is here taken into account.
Preferably, the dancer roll is provided with a movement transducer, for instance a rotary encoder or a linear, with which can be determined the stored film length to which the movement of the dancer roll corresponds. This information can be used, for instance, to determine the diameter of the supply roll.
Preferably, a dancer roll is provided in the region of the bottom and of the top film web. Preferably, the supply roll of the bottom film web and/or of the top film web is driven with a motor such that the unwinding of the respective film web is realized with a motor drive such that the respective film web is at most only slightly tensioned.
Preferably, the packaging machine according to the invention has a sensor 39, which is preferably a web edge detection means. This web edge detection means 39 detects the position of the web edge, for instance relative to the frame of the packaging machine or to some other, preferably fixed, location. Should the web edge be located beyond a desired limit, the adjustment drive 35 is preferably activated, which then moves the shaft 23 or the frame 29 in the direction symbolized by the arrows 37 to the point where the film web is again within the desired limit.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2018 207 924.2 | May 2018 | DE | national |
| 10 2018 218 582.4 | Oct 2018 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2019/062937 | 5/20/2019 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2019/219966 | 11/21/2019 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3762125 | Prena | Oct 1973 | A |
| 3965656 | Gerben | Jun 1976 | A |
| 3979877 | Vetter | Sep 1976 | A |
| 4054251 | Henderson | Oct 1977 | A |
| 4200481 | Faller | Apr 1980 | A |
| 4691499 | Umeda et al. | Sep 1987 | A |
| 4833862 | Bortolani | May 1989 | A |
| 4996819 | Davis | Mar 1991 | A |
| 5163269 | Williams | Nov 1992 | A |
| 5170611 | Buchko | Dec 1992 | A |
| 5176334 | Dreschau | Jan 1993 | A |
| 5558263 | Long | Sep 1996 | A |
| 6033502 | Coenen | Mar 2000 | A |
| 6138439 | McMahon | Oct 2000 | A |
| 6820394 | Plourde | Nov 2004 | B2 |
| 6820399 | Send | Nov 2004 | B2 |
| 6826888 | Hendriks | Dec 2004 | B2 |
| 6843038 | Haws | Jan 2005 | B1 |
| 6868654 | Douglas | Mar 2005 | B2 |
| 8474226 | Izquierdo | Jul 2013 | B2 |
| 10065755 | Palumbo | Sep 2018 | B2 |
| 11117771 | Hada | Sep 2021 | B2 |
| 11174050 | Palumbo | Nov 2021 | B2 |
| 20020184858 | Ausnit | Dec 2002 | A1 |
| 20040123568 | Send | Jul 2004 | A1 |
| 20050247020 | Niesar | Nov 2005 | A1 |
| 20050284109 | Jones | Dec 2005 | A1 |
| 20060093794 | Yukawa | May 2006 | A1 |
| 20060230708 | Granili | Oct 2006 | A1 |
| 20080034710 | Ehrmann | Feb 2008 | A1 |
| 20090152261 | Capriotti | Jun 2009 | A1 |
| 20100011718 | Donges | Jan 2010 | A1 |
| 20100287881 | Ehrmann | Nov 2010 | A1 |
| 20110017860 | Vaughn | Jan 2011 | A1 |
| 20110061344 | Ehrmann | Mar 2011 | A1 |
| 20120199685 | Weiss | Aug 2012 | A1 |
| 20120289388 | Ehrmann | Nov 2012 | A1 |
| 20130248411 | Bader | Sep 2013 | A1 |
| 20140018220 | Wilhelm | Jan 2014 | A1 |
| 20140150377 | Ehrmann | Jun 2014 | A1 |
| 20140249007 | Ehrmann | Sep 2014 | A1 |
| 20150033679 | Takahashi et al. | Feb 2015 | A1 |
| 20150096263 | Ehrmann | Apr 2015 | A1 |
| 20150102152 | Duehring | Apr 2015 | A1 |
| 20150104563 | Lowe | Apr 2015 | A1 |
| 20150135650 | Lau | May 2015 | A1 |
| 20150185673 | Atay | Jul 2015 | A1 |
| 20150203223 | Ehrmann | Jul 2015 | A1 |
| 20150229845 | Duss | Aug 2015 | A1 |
| 20160068292 | Fries | Mar 2016 | A1 |
| 20160177983 | Ehrmann | Jun 2016 | A1 |
| 20160187484 | Bloomfield | Jun 2016 | A1 |
| 20160194101 | Palumbo | Jul 2016 | A1 |
| 20160280440 | von Sybel | Sep 2016 | A1 |
| 20170029141 | Cherney | Feb 2017 | A1 |
| 20170029150 | Ehrmann | Feb 2017 | A1 |
| 20170107070 | Franke | Apr 2017 | A1 |
| 20170113825 | Naoi | Apr 2017 | A1 |
| 20170253451 | Kito | Sep 2017 | A1 |
| 20170327257 | Sabato | Nov 2017 | A1 |
| 20180110579 | Kalyankar | Apr 2018 | A1 |
| 20180186484 | Kikuchi | Jul 2018 | A1 |
| 20180222619 | Ehrmann | Aug 2018 | A1 |
| 20190061301 | Öhman | Feb 2019 | A1 |
| Number | Date | Country |
|---|---|---|
| 202186781 | Apr 2012 | CN |
| 103193102 | Jul 2013 | CN |
| 103935811 | Jul 2014 | CN |
| 19516870 | Nov 1996 | DE |
| 102014211786 | Dec 2015 | DE |
| 0067481 | Dec 1982 | EP |
| 0872419 | Oct 1998 | EP |
| 2163499 | Mar 2010 | EP |
| 1296251 | Nov 1972 | GB |
| 1451662 | Oct 1976 | GB |
| 2014031226 | Feb 2014 | JP |
| 2017002915 | Jan 2017 | WO |
| Entry |
|---|
| Chinese First Office Action dated Dec. 24, 2021, for Chinese patent application No. 2019800333481. |
| English Translation of the International Preliminary Report on Patentability for International Application PCT/EP2019/062937, dated Oct. 22, 2020. |
| International Search Report and Written Opinion for International Application PCT/EP2019/062937, dated Sep. 6, 2019. |
| Office Action from CN Application No. 201980033348.1, dated Sep. 5, 2022. |
| Number | Date | Country | |
|---|---|---|---|
| 20210214110 A1 | Jul 2021 | US |
