Deep drawing packaging machine with a vacuum cooling station and method for vacuum cooling hot-packaged products

Abstract

The present invention relates to a deep-drawing packaging machine (1) having a forming station (2) for deep-drawing a tray (11) into a film (9), a loading section (12) for filling the product (13) into the tray (11), and a sealing station (4) for sealing the tray (11), characterized in that the deep-drawing packaging machine (1) includes at least one vacuum cooling station (3) which is located upstream of the sealing station (4) in the transport direction (R) and is configured to perform vacuum cooling on the product (13) placed in the tray (11) along the loading section (12). The present invention also relates to a method for vacuum cooling a product (13).

Description

Technical Field

[0001] The present invention relates to a deep-drawing packaging machine having a vacuum cooling station. The present invention also relates to a method for vacuum-cooling hot-packaged products. Background Art

[0002] Such a deep-drawing packaging machine is used to manufacture tray-shaped packages, wherein the product to be packaged is filled into the manufactured trays along the loading section of the deep-drawing packaging machine, and then the filled trays are transported to a sealing station for sealing the trays.

[0003] If the product placed in the tray is a hot product, such as a pre-cooked filled pasta meal, it can be slightly cooled by the evacuation process performed in the sealing station. However, since the evacuation phase employed in the sealing station cannot last long enough, the associated cooling effect is insufficient to cool the product to the desired temperature level before the sealing process. However, encapsulating an overheated product can cause undesirable deposits to accumulate inside the sealed package.

[0004] DE 296 07 689U1 discloses a deep-drawing packaging machine having a sealing station, which has a mechanical cooling device downstream in the transport direction, and the mechanical cooling device presses on the sealed packages from above and below by using cooling pads mounted thereon in order to cool them downstream of the sealing station after the sealing process. Summary of the Invention

[0005] The present invention is based on the following object: to provide a deep-drawing packaging machine and a method by which, in particular, products to be hot-packaged can be packaged with a uniform packaging quality and at an increased machine output rate.

[0006] This object is achieved by the following deep-drawing packaging machine and method.

[0007] A deep-drawing packaging machine according to the present invention includes a forming station for deep-drawing a tray into a film, a loading section for filling the tray with a product, and a sealing station for sealing the tray. According to the present invention, the deep-drawing packaging machine includes at least one vacuum cooling station which is arranged upstream of the sealing station in the transport direction and is configured to perform vacuum cooling on the product placed in the tray along the loading section. The thermally introduced product can be pre-cooled to a desired (pre-) temperature level at a certain point upstream of the sealing station in the transport direction on the deep-drawing packaging machine before being transported to the sealing station for the sealing process. This particularly ensures that the product filled with heat along the loading section is cooled before entering the sealing station so that the product reaches the desired temperature level before the sealing process, such that the evacuation process carried out in the sealing station only needs to provide a reduced cooling capacity. Thus, with the present invention, the actively controlled product cooling has started upstream of the sealing station in a separate vacuum cooling station according to the present invention. In this way, in terms of the sealing process, the product can be brought to the predetermined temperature level precisely and at a fixed time in a particularly efficient manner.

[0008] Preferably, the vacuum cooling station and the sealing station exist on the deep-drawing packaging machine in the form of spatially separated workstations and are respectively configured to form at least one hermetically sealable evacuation chamber. In this way, the cooling of the thermally filled product can be selectively distributed to different workstations, such that the product can be cooled to the desired temperature level more effectively due to the continuous cooling effect obtained.

[0009] A variant provides that the vacuum cooling station includes a plurality of hermetically sealable evacuation chambers arranged continuously in the transport direction. In this way, a plurality of evacuation chambers are used upstream of the sealing station on the deep-drawing packaging machine, and the product passing through them can be gradually cooled by using the plurality of evacuation chambers, such that the cooling process can be divided into multiple machine working cycles. This results in a significantly increased machine output while maintaining consistent packaging quality. This allows the product to be cooled particularly slowly, that is, cooled a little in each cooling chamber.

[0010] Advantageously, the vacuum cooling station provides a separate vacuum pump. This means that the vacuum cooling station can perform the evacuation process independently of other workstations of the deep-drawing packaging machine, just like a self-sufficiently operating workstation. In particular, the operation of the vacuum pump of the vacuum cooling station is independent of the operation of the vacuum pump used at the sealing station, such that the cooling process at the vacuum cooling station can be better controlled in a product-specific manner.

[0011] As an alternative, it can be conceived that the evacuation processes occurring at the sealing station and the vacuum cooling station are carried out simultaneously by a shared vacuum pump. The sealing station and the vacuum cooling station almost have the same vacuum pump.

[0012] A preferred variant provides that the vacuum cooling station includes at least one filter unit for the ventilation process. Then the filtered air can be used to ventilate the vacuum cooling station, which prevents the product from being contaminated by bacteria.

[0013] The sealing station and the vacuum cooling station, in particular their chamber walls, can preferably be heated to a predetermined temperature level. In this way, precipitation of moisture in the sealing station and the vacuum cooling station can be prevented or at least reduced.

[0014] Preferably, the deep-drawing packaging machine includes at least one condenser for selectively removing moisture. For example, the condenser can be used to selectively separate moisture from the extracted air of the sealing station and / or the vacuum cooling station, which particularly results in a hygienic operation of the deep-drawing packaging machine. It is conceivable that the sealing station and / or the vacuum cooling station transfer the extracted air from the respective extraction chamber to the condenser via a heating line, in which the moisture can be separated from the heated extracted air.

[0015] Preferably, the vacuum cooling station can be installed on the frame of the deep-drawing packaging machine at an optional different position upstream of the sealing station. This means that the vacuum cooling station can be used in a more flexible manner to pre-cool products filled at different temperatures. One variant provides linear guides on the frame, on which the vacuum cooling station is mounted such that it can be displaced in the transport direction.

[0016] A particularly advantageous variant provides that the vacuum cooling station is configured in the form of a rollable carriage unit, which can be temporarily positioned in a position-fixed manner on the deep-drawing packaging machine. This enables the vacuum cooling station to be used movably on the deep-drawing packaging machine. The vacuum cooling station in the form of a rollable carriage unit is particularly suitable for maintenance and cleaning purposes.

[0017] In order to pre-treat the filled product, the vacuum cooling station can include a protective gas device, which forms a gas flushing for the product subsequently vacuum-cooled therein. This means that a gas envelope can be provided for the filled product for further transportation.

[0018] Preferably, the opening and closing of the vacuum cooling station can be synchronized with the opening and closing of the sealing station located downstream in the transport direction. It is conceivable that the opening and closing of the vacuum cooling station are triggered by the opening and closing of the sealing station.

[0019] Preferably, the deep-drawing packaging machine comprises a control unit for controlling and monitoring the processes running at the vacuum cooling station, regardless of the form in which the vacuum cooling station is present upstream of the sealing station on the thermoforming packaging machine and / or at which position the vacuum cooling station is present. In particular, this can be the same control unit which is also provided for controlling other workstations of the deep-drawing packaging machine, for example, the forming station and / or the sealing station for producing trays located at the inlet on the machine frame.

[0020] Regarding the product temperature recorded along the loading section, one variant provides for being able to activate the evacuation pressure which can be varied at the vacuum cooling station and / or being able to control the evacuation pressure curve running therein, for example, in the form of a controlled pressure curve. In this way, regarding the measured product temperature, the cooling process can be carried out in a product-specific manner within the vacuum cooling station, such that it is possible to seal products with a uniform product temperature within the sealing station. In other words, the products can thus be supplied to the sealing station at a desired product temperature, such that it is possible to seal packages with a uniform product quality therein.

[0021] It is conceivable that the vacuum cooling station comprises a temperature measuring unit in the form of, for example, a temperature sensor or a thermal imaging camera, by means of which the product temperature of the product available immediately upstream of the vacuum cooling station can be recorded, based on which the evacuation process can be controlled. Alternatively, the temperature measuring unit can be present as a separate unit upstream of the vacuum cooling station.

[0022] The invention also relates to a method for cooling products placed in trays along the loading section of a deep-drawing packaging machine. According to the invention, the products placed in the trays are cooled outside the sealing station within the vacuum cooling station of the deep-drawing packaging machine located upstream of the sealing station in the transport direction by a controlled evacuation process. In this way, the products placed in the trays have already reached a reduced temperature level outside the sealing station, based on which better packages with consistent quality can be produced by the subsequent processes carried out within the sealing station. The cooling of the products upstream of the sealing station actively controlled within the vacuum cooling station has already led to at least a partial cooling effect, which is advantageous for the subsequent processes carried out within the sealing station. In particular, the products can be precisely brought to the desired temperature level until the sealing process is carried out. Description of the Drawings

[0023] The advantageous embodiments of the invention will be further illustrated below based on the drawings, wherein

[0024] Figure 1 a deep-drawing packaging machine with a vacuum cooling station is shown,

[0025] Figure 2 a deep-drawing packaging machine with a vacuum cooling station in the form of a carriage unit is shown, and

[0026] Figure 3 A deep-drawing packaging machine with a multi-chamber vacuum cooling station is shown. Detailed implementation

[0027] In all the figures, the same reference numerals denote the same components.

[0028] Figure 1 A deep-drawing packaging machine 1 with intermittent operation according to the present invention is shown. The deep-drawing packaging machine 1 includes a forming station 2, a vacuum cooling station 3, a sealing station 4, a transverse cutting device 5, and a longitudinal cutting device 6 that are sequentially arranged on a frame 7 in the transport direction R.

[0029] A supply roller 8 is arranged on the inlet side of the frame, and a base film 9 is drawn out from the supply roller 8. In addition, the deep-drawing packaging machine 1 includes a transport chain 10 that grips the base film 9 and transports the base film 9 forward in the transport direction R in each main working cycle.

[0030] In accordance with Figure 1 In the illustrated embodiment, the forming station 2 is configured as a deep-drawing station, where trays 11 are formed into the base film 9 by deep-drawing using, for example, compressed air and / or vacuum. The forming station 2 can be configured such that a plurality of trays 11 are formed adjacent to each other in a direction perpendicular to the transport direction R. A loading section 12 is provided downstream of the forming station 2 in the transport direction R, and in this loading section, the trays 11 formed in the base film 9 are filled with products 13.

[0031] The vacuum cooling station 3 includes a sealable enclosure in which the gas in the trays 11 can be evacuated. The vacuum cooling station 3 includes a vacuum pump 16 for evacuating the chamber 3a.

[0032] Figure 1 The vacuum cooling station 3 including a protective gas device 17 is also shown. The protective gas device is configured to perform gas flushing on the products 13 cooled in vacuum. Then, the products 13 transported to the vacuum cooling station 3 can be both vacuum-cooled and gas-flushed with an exchange gas or a gas mixture.

[0033] The sealing station 4 includes a sealable enclosure, in which the gas in the trays 11 is, for example, evacuated and / or replaced with a replacement gas or a gas mixture before the trays 11 are sealed using a top film 15 dispensed from a top film holder 14.

[0034] The transverse cutting device 5 can be configured as a punch that cuts the base film 9 and the top film 15 between adjacent trays 11 in a direction transverse to the transport direction R. The transverse cutting device 5 there operates in such a way that the base film is not cut across the entire width, so that the film is not cut at least in one edge region. This enables the forward transport to be controlled by the transport chain 10.

[0035] The longitudinal cutting device 6 can be configured as a blade assembly with which the base film and the top film are cut between adjacent trays 11 and at the side edges of the base film along the transport direction R, such that separate packages V are present downstream of the longitudinal cutting device 6.

[0036] The deep-drawing packaging machine 1 further comprises a control unit 18. It is for the purpose of controlling and monitoring the processes running at the workstations in the deep-drawing packaging machine 1. A display device 19 with elements 20 serves to visualize for the operator respectively the processes running in the deep-drawing packaging machine 1 or to influence the processes running in the deep-drawing packaging machine 1 by the operator.

[0037] According to Figure 1 , the vacuum cooling station 3 and the sealing station 4 are configured in the form of spatially separated workstations on the deep-drawing packaging machine 1. Different from the vacuum cooling station 3, the sealing station 4 includes its own vacuum pump 21 for performing the evacuation process within the evacuation chamber 4a. Thus, the vacuum pump 16 of the vacuum cooling station 3 and the vacuum pump 21 of the sealing station 4 exist as separate vacuum pumps 16, 21, which can be controlled separately from each other by the control unit 18.

[0038] Furthermore, Figure 1 The vacuum cooling station 3 shown in dashed lines upstream of the sealing station 4 can include more than two evacuation chambers 3a for performing a continuous vacuum cooling process. The product 13 can be cooled particularly gently thereby.

[0039] Furthermore, Figure 1 The vacuum cooling station 3 including a filter unit 22 is schematically shown, through which sterile air filtered by a ventilation process flows into the chamber after vacuum cooling.

[0040] Figure 1 A temperature measurement unit 25 is also shown, through which the product temperature T of the transported product 13 passing underneath can be measured. By means of the control unit 18 of the deep-drawing packaging machine 1, preferably the evacuation pressure and / or the evacuation pressure curve with respect to the recorded product temperature T can be set in an automated manner for each evacuation process within the downstream vacuum cooling station 3.

[0041] Figure 2 Shown is Figure 1 the deep-drawing packaging machine 1, wherein the vacuum cooling station 3 is configured in the form of a rollable carriage unit 23, which is located on the deep-drawing packaging machine 1, upstream of the sealing station 4, for cooling the product 13 by an evacuation process before the product 13 passing through it reaches the downstream sealing station 4. The carriage unit 23 forms a mobile module that is particularly suitable for being used flexibly for various types of deep-drawing packaging machines, since its positioning between the loading section 12 and the sealing station 4 can be freely selected.

[0042] Figure 3 Shows a deep-drawing packaging machine 1 having a vacuum cooling station 3 configured as a multi-chamber vacuum cooling station, which is located upstream of a sealing station 4 in the transport direction R. The individual evacuation processes are carried out successively in the chambers of the vacuum cooling station 3, which results in a controlled stepwise vacuum cooling of the product 13 before it is transported into the sealing station 4 for encapsulating the tray 11 with the top film 15.

[0043] According to Figure 3 , the vacuum cooling station 3 and the sealing station 4 are configured as directly adjacent workstations, and even an integrally formed structure can be envisaged for these two workstations. Figure 3 Also shown is a deep-drawing packaging machine 1 including a condenser 24 configured to selectively remove moisture. The condenser 24 can also be used in combination with Figure 1 and Figure 2 the vacuum cooling station 3 in

[0044] The suction line 4b leads from the sealing station 4 to the condenser 24. A corresponding suction line 3b also leads from the chambers of the vacuum cooling station 3 to the condenser 24. Preferably, the suction lines 3b, 4b are configured to be heatable so that moisture is separated from the air drawn out of the chambers only selectively at the condenser 24.

[0045] The present invention enables the products 13 thermally inserted along the loading section 12 of the deep-drawing packaging machine 1 to be cooled to a desired temperature level before they reach the sealing station 4 by vacuum cooling (stepwise when using a multi-chamber cooling system), enabling the sealing process to be carried out in the sealing station 4 in a more economical manner and with a consistent packaging quality.

Claims

1. A deep-drawing packaging machine (1) comprising a forming station (2) for deep-drawing a tray (11) into a film (9), a loading section (12) for filling the tray (11) with a product (13), and a sealing station (4) for sealing the tray (11). It is characterized in that The deep-drawing packaging machine (1) comprises at least one vacuum cooling station (3) which is arranged upstream of the sealing station (4) in the transport direction (R) and is configured to vacuum-cool the product (13) placed in the tray (11) along the loading section (12). The deep-drawing packaging machine (1) comprises at least one condenser (24) for selectively removing moisture from the air extracted from the vacuum cooling station (3). The sealing station (4) and the vacuum cooling station (3) can be heated to a predetermined temperature level to prevent or at least reduce the precipitation of moisture at the sealing station and the vacuum cooling station. The vacuum cooling station (3) comprises a plurality of sealable and closable suction chambers (3a) arranged continuously in the transport direction (R), and by using the plurality of suction chambers (3a), the product passing through them can be gradually cooled, so that the cooling process can be divided into a plurality of machine working cycles.

2. The deep drawing packaging machine according to claim 1, characterized in that, The vacuum cooling station (3) and the sealing station (4) exist on the deep-drawing packaging machine (1) in the form of spatially separated workstations and are both configured to form at least one sealable and closable suction chamber (3a, 4a).

3. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, The vacuum cooling station (3) provides a separate vacuum pump (16).

4. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, The vacuum cooling station (3) comprises at least one filter unit (22) for the ventilation process.

5. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, The vacuum cooling station (3) can be installed on the frame (7) of the deep-drawing packaging machine (1) at different positions upstream of the sealing station (4).

6. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, The vacuum cooling station (3) is configured in the form of a rollable carriage unit (23) which can be positioned on the deep-drawing packaging machine (1) in a position-fixed manner.

7. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, The vacuum cooling station (3) comprises a protective gas device (17) which is configured to gas-flush the vacuum-cooled product (13).

8. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, The opening and closing of the vacuum cooling station (3) can be synchronized with the opening and closing of the sealing station (4) located downstream in the transport direction (R).

9. The deep-drawing packaging machine according to claim 1 or 2, characterized in that The deep-drawing packaging machine (1) comprises a control unit (18) for controlling and monitoring the processes running at the vacuum cooling station (3).

10. The deep-drawing packaging machine according to claim 1 or 2, characterized in that, Regarding the product temperature (T) recorded along the loading section (12), the suction pressure and / or the suction pressure curve can be activated.

11. A method for cooling a product (13) using a deep-drawing packaging machine (1) as claimed in any one of claims 1 to 10, wherein the product (13) is placed in a tray (11) along a loading section (12) of the deep-drawing packaging machine (1), characterized in that, In a vacuum cooling station (3) upstream of the sealing station (4) in the transport direction (R) of the deep-drawing packaging machine (1), a controlled vacuum cooling process is used to cool the product (13) placed in the tray (11) outside the sealing station (4). By means of the machine cycle of the deep-drawing packaging machine (1), the product (13) placed in the tray (11) passes through a plurality of suction chambers (3a) arranged continuously at the vacuum cooling station (3) along the transport direction (R) so as to be gradually cooled.

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