DE102009030508A1 - Packaging machine has forming station for deforming web-shaped material, and has device for transferring energy to web-shaped material - Google Patents

Abstract

The packaging machine (1) has a forming station (2) for deforming a web-shaped material (8), and has a device (23) for transferring energy to the web-shaped material. A device (21) is provided for partial application of a heating agent on the web-shaped material. The heating agent is adapted to transfer energy to the web-shaped material for non-uniform heating of the web-shaped material during a spatially homogeneous energy transfer from the energy transferring device. Independent claims are also included for the following: (1) a web-shaped material with energy applications; and (2) a method for deforming a web-shaped material.

Description

The The present invention relates to a packaging machine according to the preamble of claim 1, to a web-shaped material for a packaging machine, which is thermoformable in a heated state, as well as on a method of deforming a sheet material in a packaging machine.

In In practice, various types of packaging machines are known. The most important types include thermoform packaging machines, Chamber machines, peel sealers or Shell sealing machines (also known in the trade as "tray sealers") as well as tubular bag closing machines.

Thermoforming packaging machines, for example, go from the DE 10 2007 021 397 A1 out. In thermoforming packaging machines, a sheet material is heated and deep drawn in a deep drawing tool to produce a container for receiving a product to be packaged. After the container has been formed, the product can be filled or inserted into the container, usually from above. Later, the deep-drawn containers can be sealed and sealed with a lid or foil. Prior to sealing, the packages may be evacuated and / or gassed for gas exchange or gas flushed.

For example, a tray sealing machine is made from the DE 10 2006 018 327 A1 or the DE 198 28 381 A1 out. Such machines are fed with already preformed and individualized trays, which are usually stored stacked after molding. The trays or containers are removed from the stock individually and placed on a conveyor belt, where they are filled from above with a product. Subsequently, a sealing film is usually applied to the upwardly open shells.

From the post-published DE 10 2009 020 892 It can be seen that a deep-drawing process can also be used with tray sealing machines. In this case, the deep drawing is used to deform the lidding film to form concave or convex shaped covers for the trays to be closed.

at the packaged products may be, for example, food or medical devices. Food packaged for as long as possible To be preserved, and thus packaged medical devices as possible stay sterile for a long time, it is extremely important that the packaging stays permanently tight so that the products and the surrounding atmosphere is not polluted. To achieve this goal, the container must and the lidding film even after deep drawing everywhere be stable, that damage the container or the lid and thus the penetration of impurities is avoided. The barrier property of the thermoformed film can be lost when falling below a minimum strength; this creates the danger of entering surrounding atmosphere.

task The present invention is a packaging machine and a method of their operation with constructive possible simple means to enhance both a sustainable Tightness of the packaging is guaranteed, as well the expense of changing the shape of the machine produced on the machine Packaging is minimized.

These Task is solved by a packaging machine with the features of claim 1, by a web-shaped material for a packaging machine having the features of claim 9, or by a method having the features of the claim 11. Advantageous developments of the invention are specified in the subclaims.

The inventive packaging machine has a workstation in which a web-shaped material is deep-drawn can be. The sheet material may be around the material for the cover foil or the material act for the containers themselves. The packaging machine also has a means for transmitting of energy to the web-shaped material. By the transfer of energy heats up the sheet-like material, so that it can be deep-drawn.

The inventive packaging machine records characterized by a device for at least partially applying a heat exchanger on the web-shaped material, wherein the heat facilitator is adapted to a spatially homogeneous transfer of energy to the web-shaped material for a spatially inhomogeneous warming to provide the sheet-like material.

Usually becomes the original sheet material of the Container or the lidding film on a certain surface heated homogeneously before the material is deep-drawn. The Heating causes the material in the first place in a thermoformable state. The deep-drawn form itself arises from the thermoforming tool.

The invention is based on the finding that deep-drawn packages can be more stable if the heating of the sheet-like material prior to thermoforming takes place spatially inhomogeneous. Due to the spatially inhomogeneous heating, the flow behavior of the web-like material during deep drawing can be controlled. It should be noted that the web-shaped material is subjected to different levels of stress during deep drawing at different points. At corners or edges of the thermoforming tool, the web-shaped material deforms the strongest. In these areas, therefore, the greatest danger is that the web-shaped material is weakened too much. Below a certain material thickness not only increases the risk of material fatigue, cracks or fractures, but even without the occurrence of cracks or fractures, the material can be permeable to certain gases, for example.

These Dangers can be avoided by the present invention, for example the particularly heavily used areas of the web-shaped Materials are heated less. In this way the flow and the deformation of the material will be at least partly on the less stressed areas of the web-shaped Distributed materials.

about However, this basic idea goes beyond the present invention, by applying the at least partially applying a heat transfer agent or heat generator on the web-shaped material provides. This heat transfer agent serves to heat to generate or particularly good to absorb heat and they to the provided with him areas of the web-shaped Transfer material. In these areas, the web-shaped Material therefore heated faster or stronger than in the areas not provided with the heat exchanger. Depending on the distribution of the heat mediator on the web-shaped material can thus also in a spatially homogeneous energy transfer, especially with a inexpensive, spatially homogeneous energy transfer device (For example, a hot plate) an inhomogeneous heating of the sheet material with the corresponding stability advantages be achieved.

Further Advantages unfolds the packaging machine according to the invention in that the shape of the packaging made with it very can be flexibly changed. If another heating pattern of the sheet material appears to be a To produce packaging with a different shape, the energy transfer device can not be replaced. Rather, it is sufficient, the device for the application of the heat exchanger to control so that the heat broker in a changed pattern is applied to the web-shaped material. Corresponding this changed pattern may be the web-shaped Material are then deep-drawn. Apart from one, maybe required replacement of the thermoforming tool are on the packaging machine no other mechanical setups necessary to the web-shaped material in different ways too deform.

Preferably is the device for applying the heat transfer agent for at least partial coating or printing of the web-shaped Materials configured with the heat exchanger. That has the advantage that the printing or loading pattern is very flexible from one working cycle of the packaging machine to the next Working cycle can be changed.

expedient the device is further configured to be web-shaped Material in a first area in a different layer thickness with to coat or print the heat exchanger as in a second area. This variant offers the advantage that inhomogeneous heating of the sheet material to control even finer. For example, the Heat brokers be set up so that it is all the more Produces heat and the web-like material correspondingly more heated, the thicker the layer is, in which the heat transfer agent is applied.

In In most cases, it will not be necessary to Heat transfer agent on both sides of the web-shaped Apply material. In this case, it is preferable if the Device for applying the heat transfer to the - related on the packaging - outer side of the web-shaped material is formed. In other words In this case, the heat transfer agent on the bottom of the deep-drawn container film or on the top applied to the deep-drawn lid sheet. This way you can a potentially unwanted contact between the product and the heat exchanger are avoided.

In an advantageous embodiment of the invention the heat transfer agent metallic or metallhaltig. Thereby The heat exchanger can be heated quickly. In addition, the high thermal conductivity ensures the metallic or metal-containing heat exchanger for a uniform distribution of heat over the provided with the heat exchanger areas of the web-shaped Material. Thus, both the distribution of heat, as well as deep drawing in a precisely defined way.

The heat mediator may be formed in a very different form to generate or absorb heat and then transmit it to the sheet material. For example, the heat mediator could be a chemical in which an exothermic Re can take action. The spatially homogeneous heating of the web-like material can then supply the necessary activation energy in order to allow the exothermic reaction to proceed only on the areas provided with the heat-mediator. Alternatively, the heat mediator may also be a chemical in which the delivery of another chemical triggers an exothermic reaction. If no additional activation energy is required, and if the areas of the sheet material not provided with the heat-exchanger are not to be heated at all, it may even be possible to dispense with the device for supplying energy.

A especially for the food industry harmless Variant, however, is that the means for transmitting of energy to the web-shaped material by means of electromagnetic Radiation is configured. The heat broker should then be designed to use the ones to transmit electromagnetic radiation absorbed as well as possible and converted into heat. In this way, the energy demand The packaging machine can be lowered, as the heating is almost completely on the heat exchanger and the so restricted area of the web-shaped material stays, without any further components or other area of the web-shaped Materials overly or at all would have to be heated.

For example the energy transmission device could be transmitted of energy configured by means of microwave radiation or laser radiation be. It would also be conceivable, however, that electromagnetic Radiation from other spectral regions for energy transmission used, for example, for heating by induction.

at The packaging machine may in particular be a thermoforming packaging machine or a tray sealer act.

The The invention relates not only to a packaging machine, but also to a thermoformable in a heated state, sheet material. At least in a first area This sheet material is a heat transfer agent provided on or in the material, or the heat exchanger is permanent or temporary on the web-shaped Material can be applied while in a second area of the sheet material no heat transfer agent or at least less heat mediators per unit area is provided. At an energy input on the web-shaped Material will vary depending on the distribution of Heat broker the first area more heat as the second area. This leads to the advantages described above, in particular to increased stability the packaging made with it. Even if the web-shaped Material preferably used in the packaging sector, would be It is quite possible, this material also in other technical Use areas in a deep drawing process.

The The invention also relates to a method for deforming a sheet material in a packaging machine. In this process, a heat transfer agent on the web-shaped Applied material before an energy input in the sheet-like Material takes place. With this energy input, the web-shaped Material depending on the distribution of the heat exchanger spatially inhomogeneous heating of the sheet-like material, before or while the sheet material is deformed becomes. The heating becomes spatially inhomogeneous even then be when the energy input to the web-like material even spatially homogeneous.

Preferably the application of the heat mediator is done by a Coating or printing process. Already mentioned was the possibility of being the heat broker in different areas in different layer thickness on the web-shaped material is applied.

Preferably A controller of the packaging machine controls a device for applying the heat transfer agent to the web-shaped Material to the composition of the heat exchanger, the pattern for distribution of the heat mediator on the web-shaped material and / or the local layer thickness pretend, adjust and change the heat mediator. This method allows a very flexible use the packaging machine, changing the specifications by the Control immediately in the device for applying the heat exchanger be converted into a different or more stable form of packaging can lead without further mechanical retooling operations would be required.

expedient it is when the sheet material in the deformed Areas after thermoforming everywhere at least one predetermined Has minimum wall thickness. That's how stability becomes the packaging is guaranteed in all areas and prevents permeation.

in the Below is an advantageous embodiment of Invention explained in more detail with reference to a drawing. In detail show:

1 a schematic side view of a packaging machine according to the invention in Form of a thermoforming packaging machine,

2 a bottom view of the sheet material in the in 1 designated II-II area of the packaging machine, and

3 a schematic vertical section through the web-shaped material and some components of the packaging machine to the in 2 III-III designated place.

Same Components in the figures are consistent with the same Provided with reference numerals.

1 shows a schematic view of a packaging machine according to the invention 1 in the form of a thermoforming packaging machine. The thermoforming packaging machine 1 has a molding or workstation 2 , a sealing station 3 , a cross-cutting device 4 and a slitter 5 auf, in this order in a direction R on a machine frame 6 are arranged. The input side is located on the machine frame 6 a feed roll 7 of which a first sheet-like material 8th is deducted. In the area of the sealing station 3 is a material store 9 provided, of which a second sheet-like material 10 is withdrawn as a cover sheet. On the output side is at the packaging machine 1 a discharge facility 13 provided in the form of a conveyor belt to be transported with the finished, isolated packaging. Furthermore, the packaging machine 1 a feed device, not shown, which is the first web-shaped material 8th takes and in a main working cycle in cycles in the direction R further transported. The feed device can be realized for example by laterally arranged transport chains.

In the illustrated embodiment, the working or forming station 2 formed as a thermoforming station, in which in the first sheet-like material 8th by deep-drawing containers 14 be formed. In this case, the forming station 2 be configured such that in the direction perpendicular to the working direction R a plurality of containers 14 be formed next to each other. In working direction R behind the forming station 2 is an insertion route 15 provided in which the in the first sheet-like material 8th shaped container 14 with product 16 be filled.

The sealing station 3 has a lockable chamber 17 in which the atmosphere in the containers 14 can be replaced, for example by gas purging with a replacement gas or with an exchange gas mixture before sealing.

The cross cutter 4 is formed as a punch, which is the first web-shaped material 8th and the second sheet material 10 in a direction transverse to the working direction R between adjacent containers 14 severed. The cross-cutting device works 4 such that the first sheet material 8th is not divided over the entire width ge, but is not severed at least in a peripheral area. This allows a controlled onward transport by the feed device.

The slitting device 5 is formed in the illustrated embodiment as a knife assembly with which the first sheet material 8th and the second sheet material 10 between adjacent containers 14 and at the lateral edge of the first sheet material 8th be severed so that behind the slitter 5 individual packages are available.

The packaging machine 1 also has a controller 18 , The control 18 has the job in the packaging machine 1 control and monitor ongoing processes. A display device 19 with controls 20 serves to visualize or influence the process sequences in the packaging machine 1 for or by an operator.

Between the feed roller 7 for the first sheet-like material 8th and the work station 2 for deforming the sheet material 8th is a device 21 arranged, by means of which a heat transfer agent on the web-shaped material 8th can be applied. In the present embodiment, the device has 21 via at least one printhead 22 , By means of which, if necessary, dispersed in a pressure medium heat transfer agent on the underside of the sheet-like material 8th can be printed. The heat mediator can be, for example, metallic particles, for example metallic microparticles or nanoparticles.

In working direction R is the printing device 21 An institution 23 for transmitting energy to the sheet material 8th downstream. The device 23 serves to heat the sheet material 8th so that afterwards in the forming station 2 can be deep-drawn. According to the invention, it is provided that the energy transmission device 23 the heat exchanger heated more or faster than the non-provided with the heat transfer area of the sheet material 8th , If the heat transfer agent is metallic or metal-containing particles, it could be used as energy transfer device 23 For example, a microwave radiator can be used.

2 shows a bottom view of the first sheet material 8th in the 1 II-II designated area of the packaging machine 1 , In which sheet-like material 8th it is a thermoformable plastic film. By means of the feed device of the packaging machine 1 can the plastic film 8th cyclically in the direction R be transported.

In the original state, ie when removing from the feed roller 7 , has the web-shaped material 8th Uniform material properties across its entire width.

By means of the printing device 21 becomes a heat broker 25 on the first web-shaped material 8th printed. The one single container 14 assigned print pattern consists in the present embodiment of a central area 26 and one the central area 26 annular outer region 27 , Between the two areas 26 . 27 there is an annular area 28 who is not with the heat broker 25 is provided. In a work cycle brings the printing device 21 n × m of such patterns for each individual container 14 on the first sheet-like material 8th on, where n, m are integers. In the present embodiment, n = 1, m = 2; ie in a work cycle two adjacent printing patterns 29 on the web-shaped material 8th applied. The printing patterns 29 shift at the next feed cycle to that of the feed device of the packaging machine 1 predetermined feed distance D.

3 shows a schematic vertical section through the web-shaped material 8th as well as some components of the packaging machine 1 at the in 2 with III-III designated place.

3 shows that the heat exchanger 25 in the form of a layer on the underside 30 of the sheet material 8th is printed. In the outer area 27 of the printing pattern 29 is the layer thickness d1 of the heat exchanger 25 smaller than the layer thickness d2 in the central area 26 , In the intermediate, annular area 28 does not become a heat transfer agent on the sheet material 8th applied. As in 3 is indicated, the printhead 22 the printing device 21 relative to the sheet material 8th movable. Alternatively, the printing could be done through a mask. The printing device 21 can have a reservoir (not represent) for storing a pressure medium, wherein the heat exchanger 25 is dispersed in the printing medium.

In the following, the method according to the invention or the operating sequence of the packaging machine according to the invention will be described 1 in particular with reference to 3 described.

The first web-shaped material 8th gets off the feed roll 7 withdrawn and transported by means of the feed device in the working direction R. If the sheet material 8th the printing device 21 reached there is by means of the printhead 22 a heat broker 25 in a certain pattern 29 on the web-shaped material 8th applied. In the present embodiment, the printing pattern 29 on the bottom 30 of the sheet material 8th applied, ie on the later outside of the finished packaging. In this embodiment, the printing pattern exists 29 from a central area 26 with layer thickness d2, and from an annular, outer area 27 with a smaller layer thickness d1, where the range 26 . 27 through a blank area 28 are separated from each other.

The next work cycle will be the web-shaped material 8th transported by the feed distance D on. The printed pattern 29 is now below or inside the facility 23 , by means of which energy to the web-shaped material 8th is transmitted. In the present embodiment, the device is 23 around a flat microwave radiator, the web-like material 8th over its entire surface comparatively homogeneous with microwave radiation 31 applied.

The heat exchanger 25 absorbs the microwave radiation 31 stronger than the sheet material 8th , Consequently, the heat with the heat exchanger 25 coated area 26 . 27 stronger than the uncoated area 28 of the material 8th because of the heat transfer agent 25 its heat to the web-shaped material 8th emits. The temperature distribution in the web-shaped material 8th is more inhomogeneous than the distribution of microwave radiation 31 the device 23 specified. Because of the larger layer thickness d2, the temperature in the central area 26 Beyond that higher than in the outer, annular area 27 ,

The next work cycle will be the web-shaped material 8th transported so that the coated and heated area in the forming station 2 located. The forming station 2 has an upper tool 32 and a lower tool 33 , The two tools 32 . 33 are closed so that the web-shaped material 8th between both tools 32 . 33 to an open-topped container 14 is deep-drawn.

The coating pattern 29 is formed so that the uncoated annular area 28 with the lower edge 34 of the container 14 matches. Through the edges of the tools 32 . 33 becomes the sheet material 8th most deformed in this area. Because of the lack of coating with the heat transfer agent 25 and the resulting, lower temperature than in the In other areas, the material resists 8th However, too much deformation, so that the material is stretched there less and so the risk of overloading or excessive weakening of the material at the edges 34 of the container 14 is avoided. Instead, the deformed with the heat exchanger 25 coated area 26 . 27 stronger than the area 28 , In this way, a concentration of deformation on the area 28 avoided; instead, the deformation is largely uniform over the larger areas of the areas 26 . 27 distributed. Overall, the container produced 14 this way more stable.

In the next working cycle of the packaging machine 1 the container arrives 14 to the insertion distance 15 in which a product 16 in the container 14 is filled.

Starting from the illustrated embodiment, the packaging device according to the invention 1 , the material of the invention 8th and the inventive method can be modified in many ways. For example, it could be in the packaging machine 1 also be a tray sealing machine in which the lidding film 10 first with the heat transfer agent 25 coated and then deep-drawn to covers. The heat exchanger 25 does not necessarily have to the bottom 30 of the sheet material 8th be applied, but it could also be applied to the top or both sides.

It would also be conceivable that the heat exchanger 25 not only in the packaging machine 1 on the material 8th is applied, but from the beginning in a certain pattern 29 on or in the web-shaped material 8th is available. If against the use of the heat exchanger 25 For example, health concerns may exist, the excess heat facilitator 25 after heating or after thermoforming, remove by suitable means.

The distribution pattern 29 the heat broker 25 on or in the sheet-like material 8th can differ significantly and in any way from the illustrated embodiment. In particular, the heat exchanger needs 25 not be applied in different layer thicknesses d1, d2. The heater 23 does not necessarily have to be from the forming station 2 but they could also be in the forming station 2 be integrated. The heater 23 can also be designed as induction heating, being used as a heat transfer agent 25 preferably ferromagnetic substances are to be used.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102007021397 A1 [0003]
• - DE 102006018327 A1 [0004]
• - DE 19828381 A1 [0004]
• - DE 102009020892 [0005]

Claims (15)

Packaging machine ( 1 ) with a forming station ( 2 ) for deforming a web-shaped material ( 8th ), and with a facility ( 23 ) for transferring energy to the web-shaped material ( 8th ), characterized by a device ( 21 ) for the at least partial application of a heat transfer agent ( 25 ) on the web-shaped material ( 8th ), wherein the heat exchanger ( 25 ) is designed, in the case of a spatially homogeneous transfer of energy from the device ( 23 ) for transferring energy to the web-shaped material ( 8th ) for an inhomogeneous heating of the web-shaped material ( 8th ) to care. Packaging machine according to claim 1, characterized in that the device ( 21 ) for at least partial coating or printing of the web-shaped material ( 8th ) with the heat mediator ( 25 ) is configured. Packaging machine according to claim 2, characterized in that the device ( 21 ) is configured to convey the sheet material ( 8th ) in a first area ( 26 ) in a different layer thickness with the heat transfer agent ( 25 ) to coat or print than in a second area ( 27 ). Packaging machine according to one of the preceding claims, characterized in that the device ( 21 ) for applying the heat transfer agent ( 25 ) on the outer side (in relation to the packaging) 30 ) of the sheet material ( 8th ) is trained. Packaging machine according to one of the preceding claims, characterized in that the heat exchanger ( 25 ) is metallic or metal-containing. Packaging machine according to one of the preceding claims, characterized in that the device ( 23 ) for transferring energy to the web-shaped material ( 8th ) is configured by means of electromagnetic radiation. Packaging machine according to one of the preceding claims, characterized in that the device ( 23 ) for transferring energy to the web-shaped material ( 8th ) is configured by means of microwave radiation or laser radiation. Packaging machine according to one of the preceding claims, characterized in that the packaging machine ( 1 ) is a thermoforming packaging machine. Web-shaped material ( 8th . 10 ) for a packaging machine ( 1 ), the material ( 8th . 10 ) is deep-drawable in a heated state, characterized in that at least in a first region ( 26 . 27 ) of the sheet material ( 8th . 10 ) a heat transfer agent ( 25 ) on or in the web-shaped material ( 8th . 10 ) or permanently or temporarily on the web-shaped material ( 8th . 10 ) and that at least in a second area ( 28 ) of the sheet material ( 8th . 10 ) no heat transfer agent ( 25 ) is provided, wherein at an energy input to the web-shaped material ( 8th . 10 ) the first area ( 26 . 27 ) of the sheet material ( 8th . 10 ) due to the heat mediator ( 25 ) heated more than the second area ( 28 ) of the sheet material ( 8th . 10 ). Web-shaped material according to claim 9, characterized in that the heat exchanger ( 25 ) is metallic or metal-containing. Method for deforming a web-like material ( 8th . 10 ) in a packaging machine ( 1 ), characterized in that on the web-shaped material ( 8th . 10 ) a heat transfer agent ( 25 ) is applied before an energy input into the sheet-like material, wherein the sheet-like material ( 8th . 10 ) depending on the distribution of the heat mediator ( 25 ) on the web-shaped material ( 8th . 10 ) is heated inhomogeneously in space before or while the sheet material ( 8th . 10 ) is deformed. A method according to claim 11, characterized in that the application of the heat exchanger ( 8th . 10 ) by a coating or printing process. Method according to claim 12, characterized in that the heat exchanger ( 25 ) in different areas ( 26 . 27 ) in different layer thickness on the web-shaped material ( 8th . 10 ) is applied. Method according to one of claims 11 to 13, characterized in that a controller ( 18 ) of the packaging machine ( 1 ) a device ( 21 ) for applying the heat transfer agent ( 25 ) on the web-shaped material ( 8th . 10 ) to determine the composition of the heat exchanger ( 25 ), the areas ( 26 . 27 ) of the sheet material ( 8th . 10 ) for applying the heat transfer agent ( 25 ) and / or the local layer thickness of the heat mediator ( 25 ) pretend. Method according to one of claims 11 to 14, characterized in that the web-shaped material ( 8th . 10 ) has in the deformed areas after deformation anywhere at least a predetermined minimum wall thickness.