Device and method for continuous vacuum cooling

Abstract

The invention relates to a device (1, 1', 1'', 1''') with at least one vacuum cooling station (5) which has a plurality of vacuum cooling chambers (6) which, while being moved along a cooling path (a) together with at least one product (P) accommodated therein, can each be controlled to vacuum cool the product (P) accommodated therein, wherein each vacuum cooling chamber (6) has its own control circuit device (7) configured for dynamic vacuum pressure generation.

Description

[0001] The present invention relates to a device having at least one cooling station according to claim 1. Furthermore, the invention relates to a method for vacuum cooling according to claim 13.

[0002] DE29607689U1 discloses a thermoforming packaging machine with a sealing station, which is followed in the transport direction by a mechanical cooling device which presses on sealed packages from above and below by means of cooling pads mounted thereon in order to cool them downstream of the sealing station after the sealing process.

[0003] JPS57-1021A discloses a thermoforming packaging machine with a forming station positioned at the beginning in the production direction for producing thermoforming trays, a sealing station for producing packages and a vacuum station positioned between the forming station and the sealing station for removing moisture from products enclosed therein.

[0004] US2004 / 0105927A1 discloses a thermoforming packaging machine with a pasteurization station positioned upstream of a sealing station of the packaging machine in the production direction. Within the pasteurization station, incoming products can be heat-treated by applying steam. Optionally, a vacuum cooling process can be performed following the pasteurization process.

[0005] EP4335759A2 discloses a thermoforming packaging machine with a plurality of vacuum cooling stations positioned along a filling line of the thermoforming packaging machine in order to cool successively arriving products combined in a work cycle step by step according to a machine work cycle by means of a generated vacuum so that they are cooled to a desired temperature level by the time they reach a sealing station positioned downstream.

[0006] When vacuum cooling is performed along multiple vacuum cooling stations integrated into the intermittent operation of a thermoforming packaging machine, these stations are opened and closed several times for the feed movement according to a machine cycle, the duration of which is, for example, 4 to 8 seconds, in order to carry out the vacuum cooling process in several stages. If longer cooling times are required for vacuum cooling, such as 60 to 90 seconds for cooling hot baked goods, multiple vacuum cooling stations must be used along the cooling line so that vacuum cooling can take place according to a shorter machine cycle, for example one with a duration of 4 to 8 seconds. The fact that multiple vacuum cooling stations may be necessary for the intermittent operation of a thermoforming packaging machine makes the design of the thermoforming packaging machine complex and energy-intensive, which increases manufacturing costs.In order to open the vacuum cooling stations for intermittent feed motion of the respective work cycles, they must also be ventilated after evacuation. This means that vacuum pressure must be repeatedly built up and then released again in the respective vacuum cooling stations. This repeated interruption of the vacuum cooling process on intermittently operating thermoforming packaging machines is time- and energy-intensive and can lead to unnecessary stress on the products pressurized by evacuation and / or venting, and possibly even damage.

[0007] WO2017053682A1 discloses a rotary machine with vacuum chambers for vacuuming products contained in packages and for sealing the vacuum-sealed packages while they are moved along a circular path. The rotary machine has a valve device by means of which various vacuum processes run intermittently depending on the position of the vacuum chambers.

[0008] The object of the present invention is to provide a device and a method for economical, in particular gentle, vacuum cooling of products.

[0009] This object is achieved by means of a device according to claim 1. Furthermore, the object is achieved by a method according to claim 13.

[0010] Advantageous further developments of the invention are given by the respective subject matters of the subclaims.

[0011] The invention relates to a device with at least one vacuum cooling station comprising a plurality of vacuum cooling chambers, each of which, while being moved along a cooling path together with at least one product accommodated therein, can be controlled to vacuum-cool the product accommodated therein. According to the invention, each vacuum cooling chamber has its own control loop configured for dynamic vacuum pressure generation. This allows the transport of the products, as well as the vacuum cooling of the products carried out during transport, to take place continuously along the entire cooling path.

[0012] According to the invention, the vacuum cooling chambers moved along the cooling section can be controlled independently, in particular position-independently of one another, to carry out respective vacuum cooling processes. The respective vacuum cooling processes can be controlled without interruptions, i.e. continuously throughout the entire movement of the vacuum cooling chambers, so that the products accommodated therein can be vacuum-cooled along the cooling section in a continuous process, position-independently of the respective vacuum cooling chambers. For the vacuum cooling process of one product or a product format comprising several products, a single closing and opening of the respective vacuum cooling chamber is sufficient. This results in energy-efficient operation of the device and a cooling process that is gentle on the products. Likewise, due to the elimination of intermittent vacuum cooling steps, the invention enables an increased output of vacuum-cooled products.

[0013] By integrating the control loop devices according to the invention into the respective vacuum cooling chambers, it is possible to carry out controlled, continuous vacuum generation within the vacuum cooling chambers regardless of the position of the respective vacuum cooling chambers along the cooling line. The movement sequence can thus be functionally decoupled from the vacuum control at the respective vacuum cooling chambers. This promotes both continuous transport and continuous cooling of the products.

[0014] In the invention, the vacuum cooling chambers each form self-contained modules for vacuum control. The components used for this purpose are structurally integrated into the respective modules. This integral design, in itself, leads to more complex vacuum cooling chambers. However, because the vacuum cooling chambers are moved along the cooling line during vacuum control, the transport and vacuum cooling of the products can take place continuously. This leads to an increased output of vacuum-cooled products.

[0015] Preferably, the control loop devices are each configured for wirelessly receiving a vacuum target pressure gradient as a reference variable for dynamic vacuum pressure generation. This wireless signal transmission can simplify the design of the cooling station, in particular the design of a drive device for the vacuum cooling chambers. In particular, the control loop devices can each be configured for wirelessly receiving a ventilation target pressure gradient as a reference variable for dynamic ventilation pressure generation.

[0016] The wireless reception of the vacuum or ventilation target pressure gradient used as a reference variable can be achieved via a WLAN configured for data transmission, to which the control circuit devices of the respective vacuum cooling chambers are functionally connected. This particularly facilitates a simplified design of the equipment used for product transport.

[0017] According to one variant, all control loop devices are configured for wireless reception of all data signals required for controlling the respective vacuum cooling processes, so that only the power supply of the respective control loop devices is wired. Each vacuum cooling chamber thus forms a functioning system for controlling the respective vacuum cooling process.

[0018] An advantageous embodiment of the invention provides that the device has a common control device for the respective control loop devices for maintaining the respective vacuum target pressure gradient. This control can, for example, be present as a central control device for several machines that work together in conjunction with the device according to the invention. Alternatively, each vacuum cooling chamber can have its own control device to provide the respective vacuum and ventilation target pressure gradients.

[0019] It would be expedient if the control loop devices each had at least one controllable valve unit. Preferably, the respective valve unit for dynamic evacuation and / or dynamic venting had at least one adjustable throttle, a proportional valve, and / or a servo valve. This allows the flow cross-section to be varied in order to individually control the evacuation and / or venting with respect to their respective reference variable at the respective vacuum cooling chambers. Preferably, the valve unit comprises separate, controllable valves for evacuation and venting, in particular separate proportional valves and / or servo valves.

[0020] Preferably, the valve unit has at least one valve that can be switched in parallel with the throttle, the proportional valve, and / or the servo valve for an unregulated, maximum evacuation and / or ventilation capacity. This valve can be opened to accelerate pressure reduction during evacuation and / or to accelerate pressure buildup during ventilation, in particular in addition to the throttle, the proportional valve, and / or the servo valve.

[0021] Preferably, the respective control loop devices have at least one vacuum pump. The respective vacuum pumps are configured to generate a vacuum within the vacuum cooling chambers fluidically connected to them. It would be conceivable for the control loop devices to be connected to a central vacuum pump shared by them. The central vacuum pump can be connected to the respective valve units in such a way that pressure reduction and / or pressure buildup can be controlled independently of one another using the valve units in the associated vacuum cooling chambers.

[0022] Preferably, the control loop devices each comprise at least one pressure sensor for detecting an actual vacuum pressure gradient as a controlled variable. In particular, the respective pressure sensors are configured to continuously detect an actual pressure present within the respective vacuum cooling chambers during evacuation.

[0023] One variant provides that the respective control loop devices are designed to determine a manipulated variable for the respective valve unit during an evacuation of the respective vacuum cooling chamber, taking into account a target / actual comparison of an actual pressure gradient determined on the basis of actual pressure values ​​detected by the pressure sensor with the respective received vacuum target pressure gradient, by means of which the respective valve unit can be controlled from an initial pressure until a final vacuum pressure is reached within the respective vacuum cooling chamber. The target / actual comparison carried out here of the vacuum target pressure gradient (reference variable) with the actual pressure gradient determined on the basis of the fed-back, measured actual pressure values ​​(controlled variable) may lead toto a control deviation, on the basis of which a controller of the respective control loop devices dynamically adjusts the manipulated variable for the evacuation process in order to dynamically influence the evacuation process via the valve unit based on the manipulated variable in such a way that a desired evacuation pressure curve can be specifically created within the respective vacuum cooling chamber. Using the respective control principle, the evacuation process can be specifically influenced depending on the product to be cooled and the predetermined vacuum target pressure gradient or the desired vacuum pressure curve in order to carry it out effectively and gently in a product-specific manner. Above all, using the present control principle it is possible to actively control the amount of water vapor extracted from the product during evacuation, taking into account a falling product temperature during evacuation, by dynamically adjusting the manipulated variable.

[0024] Preferably, the respective control loop devices are designed to determine a control variable for the valve unit during ventilation of the respective vacuum cooling chamber, taking into account a target / actual comparison of an actual pressure gradient determined on the basis of actual pressure values ​​detected by the pressure sensor with the respective received ventilation target pressure gradient, by means of which the valve unit can be controlled from the final vacuum pressure reached, at least temporarily, until an adjustable ventilation pressure is reached, which preferably corresponds to the initial pressure of the evacuation process. The target / actual value comparison of the ventilation target pressure gradient (reference variable) with the actual pressure gradient determined on the basis of the fed-back, measured actual pressure values ​​(controlled variable) carried out during ventilation in this variant may lead toto a control deviation, on the basis of which a controller of the respective control loop device dynamically adjusts the manipulated variable for the aeration process in order to dynamically influence the aeration process via the valve unit based on the manipulated variable in such a way that a desired aeration pressure curve can be created. This allows the aeration process to be specifically influenced depending on the product to be cooled and the predetermined aeration target pressure gradient or the desired aeration pressure curve in order to carry it out effectively and gently for each product. Above all, this variant makes it possible to actively control the forces generated by the aeration pressure and acting on the product during aeration by dynamically adjusting the valve setting in such a way that the products are not damaged.

[0025] It would be expedient if the respective control loop devices had at least one temperature detection unit, for example, a thermal imaging camera or an infrared thermometer. This could be integrated into the respective vacuum cooling chambers to detect a product temperature before, during, and / or after evacuation and / or venting. Based on this, possibly based on an averaged product temperature of several products accommodated in the respective vacuum cooling chambers, a dynamic adjustment of the respective reference variables in the control loop devices could take place, in particular a dynamic adjustment of the vacuum target pressure gradient or the desired vacuum pressure curve.

[0026] An advantageous variant provides that the valve unit is adjustable, at least temporarily during evacuation, to maintain a constant steam mass flow or steam volume flow, particularly taking into account a decreasing vacuum target pressure gradient maintained by the control circuit device. The valve unit thus counteracts the increasing water vapor extraction associated with decreasing pressure. This promotes particularly gentle evacuation. An expedient variant provides that the valve unit is adjustable, at least temporarily during aeration, to maintain a constant force generated by the pressure buildup, particularly taking into account a decreasing vacuum target pressure gradient maintained by the control circuit device. This prevents the cooled products from being damaged during aeration.

[0027] According to one variant, the device has a central power supply for the respective control loop devices. For example, a central power supply via a rotary feedthrough would be conceivable. The rotary feedthrough can be part of a carousel transport device configured to move the vacuum cooling chambers along a circular cooling path.

[0028] It would be advantageous if the vacuum cooling station had at least one drive device for linear and / or non-linear movement of the vacuum cooling chambers along the cooling section. The type of drive device may depend on the machines the device is used with and the space available at the installation site.

[0029] According to one embodiment, the drive device comprises opposing drive units for moving respective chamber halves of the vacuum cooling chambers. These drive units can each have a return line for returning the respective chamber halves from an outlet to an inlet of the vacuum cooling station. At the inlet, related chamber halves can be brought together by means of the drive units to form a closed vacuum cooling chamber.

[0030] According to one variant, sections of a product conveyor, for example a conveyor belt, are clamped between opposite, merged chamber halves along the cooling section to form a plurality of vacuum cooling chambers that move synchronously with the product conveyor along the cooling section.

[0031] One variant provides for the respective vacuum cooling chambers to be lockable along the cooling line. This improves process reliability.

[0032] According to one embodiment, the drive device comprises a plurality of hood-shaped covers for forming the vacuum cooling chambers. The respective control circuit devices can be structurally integrated into or on these covers.

[0033] It would be conceivable for the vacuum cooling chambers to have a closed chamber wall formed by a product conveyor. This product conveyor, for example in the form of a conveyor belt, could be combined with a hood-shaped cover placed on top to form a hermetically sealed vacuum cooling chamber. At the outlet of the vacuum cooling station, the cover can separate from the product conveyor and return via a return line to the inlet of the vacuum cooling station, where it can once again form a vacuum cooling chamber with the product conveyor along the cooling section.

[0034] One variant provides for the device to have a conveyor system for continuously feeding products into the vacuum cooling station. This can be a conveyor belt assigned to the vacuum cooling station. This can be moved continuously, synchronously with the vacuum cooling chambers.

[0035] In particular, a packaging line with a baking line, a device according to the invention, and a flow-wrapping machine would be conceivable. In this variant, the device, configured according to the invention as a cooling line, follows the baking line in the direction of production in order to continuously receive products from the baking line, cool them during continuous onward transport, and transfer them in cooled form to the flow-wrapping machine, along which the cooled products can be packaged. A U-shaped packaging line would be conceivable for this purpose, in which the baking line and the flow-wrapping machine are aligned in opposite directions to one another and the device configured as a cooling line is arranged in the form of a rotary machine in the product flow between the baking line and the flow-wrapping machine. This enables a compact design to enable a continuous overall process.

[0036] The invention further relates to a method for vacuum cooling products accommodated in continuously moving vacuum cooling chambers. According to the invention, each vacuum cooling chamber, while being moved along a cooling section together with at least one product accommodated therein, is operated by a dedicated control circuit device configured thereon for dynamic vacuum pressure generation. This allows the transport of the products and the vacuum cooling of the products performed during transport to take place continuously along the entire cooling section.

[0037] Preferably, the control loop devices each wirelessly receive a vacuum target pressure gradient as a reference variable for dynamic vacuum pressure generation. This wireless signal transmission can simplify the design of the cooling station, in particular a drive device for the vacuum cooling chambers.

[0038] According to one embodiment of the invention, the desired vacuum pressure gradients are formed as a function of the temperature of the products to be cooled. It would be expedient if the respective control loop devices, by means of at least one temperature detection unit formed thereon, for example by means of a thermal imaging camera or an infrared thermometer, detect a product temperature in the respective vacuum cooling chambers before, during, and / or after evacuation and / or venting. Based on this, possibly based on an averaged product temperature of several products accommodated in the respective vacuum cooling chambers, a dynamic adjustment of the respective reference variables could be carried out at the control loop devices, in particular a dynamic adjustment of the desired vacuum pressure gradient or the desired vacuum pressure curve could be carried out.

[0039] The products, in particular baked goods, preferably have a core temperature of below 35°C after vacuum cooling, in particular between 18°C ​​and 25°C. Preferably, the product or baked good has a core temperature of at least 70°C, preferably at least 78°C, and more preferably at least 85°C, at the start of vacuum cooling in the vacuum cooling chamber.

[0040] In particular, during vacuum cooling, the products can be cooled by at least 5°C, preferably at least 10°C, preferably at least 15°C, preferably at least 20°C, preferably at least 25°C, preferably at least 30°C, preferably at least 35°C.

[0041] Embodiments of the invention are explained in more detail with reference to the following figures. They show: Fig. 1 a packaging line with a baking device, a device for vacuum cooling baked products and a flow-wrapping machine for packaging chilled products in a schematic representation, Fig. 2 a device for continuous vacuum cooling of products in schematic representation, Fig. 3 shows a further device for continuous vacuum cooling of products in a schematic representation, Fig. 4 shows a further device for continuous vacuum cooling of products in a schematic representation, and Fig. 5 a continuous vacuum cooling process according to the invention and a stepwise vacuum cooling process not according to the invention in a schematic representation.

[0042] Technical features are provided with the same reference symbols throughout the figures.

[0043] Fig. 1 shows a packaging system A. The packaging system A has a device 1 which is configured for the continuous vacuum cooling of products P transported along it. According to Fig. 1, the device 1 is configured as a rotary machine 2. Upstream of the device 1 configured as a rotary machine 2, a baking device 3 is arranged to continuously feed hot baked goods or products P to the device 1. These products P are continuously vacuum-cooled during their transport along the device 1 in order to be transferred at a desired temperature level to a downstream flow-wrapping machine 4. The flow-wrapping machine 4 is designed to package the vacuum-cooled products.

[0044] The device 1 for vacuum cooling the products P forms a vacuum cooling station 5 with several vacuum cooling chambers 6 between the baking device 3 and the flow-wrapping machine 4. The device 1 configured as a vacuum cooling station 5 could alternatively be placed between other devices or machines for the removal of hot products P and for the delivery of vacuum-cooled products P in order to continuously cool the products P during their transport by means of a vacuum. It would be conceivable, for example, for the device 1 configured as a vacuum cooling station 5 to continuously transfer vacuum-cooled products to a buffer station, for example at least to a conveyor belt, from which the vacuum-cooled products P are fed to an intermittently operating packaging machine, for example a thermoforming packaging machine, according to a main machine work cycle.In such a packaging system, gentle, particularly time-reduced, continuous vacuum cooling of hot products could be combined with an intermittent packaging process.

[0045] Fig. 1 shows that the respective vacuum cooling chambers 6 have separate, i.e., their own control devices 7, i.e., each comprises a control device 7 configured independently for dynamic vacuum pressure generation. One of these control circuit devices 7 is shown in a schematically enlarged representation in Fig. 1 shown.

[0046] The respective control circuit devices 7 are designed for wireless reception of a vacuum target pressure gradient V as a reference variable for dynamic vacuum pressure generation. According to Fig. 1, the device 1, in particular the packaging system A, has a controller 8. The controller 8 has the task of controlling and monitoring the processes taking place on the device 1, in particular as a whole along the packaging system A, in particular the vacuum cooling carried out continuously during the transport of the products P along the device 1. In particular, the controller 8 forms a transmitter, preferably a transceiver, in order to wirelessly transmit the desired vacuum pressure gradients as reference variables to the respective vacuum cooling chambers 6. For this purpose, the respective vacuum cooling chambers 6 can be provided with individual addresses in order to be able to reliably receive data signals from the controller 8 wirelessly, for example via WLAN, in the existing network.

[0047] The control device 7 from Fig. 1 has a regulator 9, a valve unit 10 and a vacuum pump 11. As an alternative to the shown integrated design of the vacuum pump 11 on the rotary machine 2, the vacuum pump 11 could be positioned as a central vacuum pump 11, for example on a turntable of the rotary machine 2 or completely isolated from it (in Fig. 1 as a dashed, schematic representation of the vacuum pump 11). As a central vacuum pump 11 used by all vacuum cooling chambers 6, it is connected to the respective valve units 10 of the vacuum cooling chambers 6.

[0048] According to Fig. 1, the controllable actuators are all integrated into the structure of the vacuum cooling chamber 6, in particular are located on a cover formed thereon. The vacuum pump 11 could, however, also be positioned in isolation from the respective vacuum cooling chambers 6 in order to be used jointly as a central vacuum pump 11 by the respective vacuum cooling chambers 6. The valve unit 10 and / or the vacuum pump 11 can be dynamically controlled, taking into account a target-actual comparison 12 between a detected vacuum-actual pressure gradient 13 or actual pressure fed back into the control loop during evacuation, with the maintained vacuum-target pressure gradient V by means of the control deviation e formed therefrom and a manipulated variable 14 that can be produced therefrom, in order to continuously and dynamically control the evacuation process during the transport of the products P in the respective vacuum cooling chamber 6.To detect the actual vacuum pressure gradient 13, at least one pressure sensor 15 can be used on the control circuit device 7.

[0049] The respective control circuit devices 7 of the vacuum cooling chambers 6 of the Fig. 1 may have a central power supply 16. The central power supply 16 is located in Fig. 1 via a rotary union 17. Thus, the design of the device 1 in Fig. 1 ensures that only power is supplied to the vacuum cooling chambers 6 via a cable from outside. All data signals required for control are sent wirelessly or received by the vacuum cooling chambers 6. Furthermore, the respective control circuit components used for continuous evacuation are all provided on the respective vacuum cooling chambers 6 in order to be able to evacuate them independently of one another.

[0050] The Fig. The vacuum cooling chambers 6 shown schematically in Figure 1 can have plate-shaped product conveyors for transporting the products P, which can be brought together by means of hood-shaped cover parts that can be placed thereon to form hermetically sealed vacuum cooling chambers 6.

[0051] The baking device 3 from Fig. 1 is assigned a temperature detection device 30 for detecting a product temperature C at the output. The temperature detection device 30 is functionally connected to the controller 8. Based on the temperature measurements, for example an average product temperature C of several products P that are to be fed together to a vacuum cooling chamber 6, the controller can send an adapted vacuum target pressure gradient V to the control circuit device 7 of this vacuum cooling chamber 6 in order to carry out the vacuum cooling process individually therein depending on the detected, (averaged) product temperature C. For this function, i.e. for the temperature-dependent determination of specific vacuum target pressure gradients V, it would be conceivable to equip the respective vacuum cooling chamber 6 itself with a corresponding temperature detection unit in order to measure the temperature of products P arriving therein and forward it to the controller 8.The function described here in connection with temperature measurement can also be used on the versions shown in the following figures.

[0052] Fig. 2 shows an isolated, schematic representation of a device 1' configured for the continuous vacuum cooling of products P transported on a product conveyor 18, in particular on a conveyor belt, in the transport direction R. During the transport of the products P in the transport direction R, they are continuously vacuum-cooled by means of the device 1' assigned to the product conveyor 18. For this purpose, vacuum cooling chambers 6 are formed one behind the other along the device 1' in order to continuously vacuum-cool the products P during their transport in the transport direction R.

[0053] The vacuum cooling chambers 6 from Fig. 2 are each formed from combined lower and upper chamber halves 6a, 6b, which are moved along a transport path a synchronously with the product conveyor 18 in the transport direction R and thereby continuously vacuum-cool the products P enclosed therein during their transport.

[0054] To move the chamber halves 6a, 6b, opposite drive units 19a, 19b are Fig. 2. At the respective vacuum cooling chambers 6 from Fig. 2, autonomous control devices 7 are provided in order to be able to control the vacuum cooling processes taking place therein independently of one another.

[0055] In schematic top view, Fig. 2 further illustrates how the product P transported on the product conveyor 18 can be enclosed by the chamber halves 6a, 6b during the continuous cooling process. The chamber halves 6a, 6b extend laterally beyond the width of the product conveyor 18 to form the vacuum cooling chambers 6 therebetween.

[0056] Fig. 3 shows an alternative device 1" for the continuous vacuum cooling of products P while they are transported along the transport direction R on the product conveyor 18. In this variant, the respective vacuum cooling chambers 6 are formed by the product conveyor 18 and hood-shaped covers 20 placed thereon in order to regulate the respective vacuum processes therein. From the Fig. 3, it can be seen that the hood-shaped covers 20, in horizontal projection, are seated completely within a span of the product conveyor 18, for example on a conveyor belt, in order to define the vacuum cooling chambers 6 together with the latter. The device 1" from Fig. 3 therefore forms, relative to the device 1', Fig. 2 a space-reduced vacuum cooling device for continuous vacuum cooling of the transported products P.

[0057] Fig. 4 shows a further device 1''', which is configured for the continuous vacuum cooling of products P fed to it. The device 1''' of Fig. 4 has lower chamber halves 21a, 21b which are mounted so as to be adjustable in and against the transport direction R. These can be combined with chamber halves 22a, 22b positioned above them in such a way that they each form vacuum cooling chambers 6 in order to be able to vacuum-cool products P received therein continuously during their transport in the transport direction R, if necessary even against the transport direction R.

[0058] The upper chamber halves 22a, 22b can be moved back from the outlet of the device 1''' via a common return 23 in order to re-enclose hot products P supplied to the device 1'''. Fig. In the device 1''' shown in Fig. 4, in particular the two lower chamber halves 21a, 21b together with their linear drive device 24, which is configured to adjust the two chamber halves 21a, 21b in and against the transport direction R, can be integrated within the structure of the product conveyor 18.

[0059] The products P can be supplied to the product conveyor 18 from a Fig. 4, in particular a feed belt. The cooled products P can be transferred from a Fig. 4. A picker device (not shown) may be associated with this device to pick up the cooled products P from the discharge belt 28 and transfer them to a packaging machine, for example, a downstream, intermittently operating thermoforming packaging machine.

[0060] Fig. 5 shows a pressure curve 25 according to which a continuous vacuum cooling takes place, for example a vacuum cooling of products P from an initial pressure P carried out continuously by means of the device 1, 1', 1'', 1'''. A up to a final vacuum pressure P E .

[0061] Furthermore, Fig.5 shows a schematic representation of a pressure curve 26 for a stepwise vacuum cooling process. Such a vacuum cooling process occurs in particular along an intermittently operating packaging machine, at vacuum cooling stations integrated therein and mounted one behind the other in a stationary manner. These stations are intermittently closed and opened according to a main machine work cycle of the packaging machine in order to carry out the respective vacuum cooling processes step by step, i.e., with interruptions, one after the other.

Claims

[1] Device (1, 1', 1'', 1''') with at least one vacuum cooling station (5) which has a plurality of vacuum cooling chambers (6) which, while being moved along a cooling path (a) together with at least one product (P) accommodated therein, can each be controlled for vacuum cooling the product (P) accommodated therein, wherein each vacuum cooling chamber (6) has its own control circuit device (7) configured for dynamic vacuum pressure generation. [2] Device according to claim 1, characterized by that the control circuit devices (7) are each designed for wireless reception of a vacuum target pressure gradient (V) as a reference variable for dynamic vacuum pressure generation. [3] Device according to claim 1 or 2, characterized by that the device (1, 1', 1'', 1''') has a common control device (8) for the respective control circuit devices (7) for maintaining the respective vacuum target pressure gradient (V). [4] Device according to one of the preceding claims, characterized by that the control circuit devices (7) each have at least one controllable valve unit (10) and / or a vacuum pump (11). [5] Device according to one of the preceding claims, characterized by that the control circuit devices (7) each comprise at least one pressure sensor (15) for detecting a vacuum actual pressure gradient (13) as a controlled variable. [6] Device according to one of the preceding claims, characterized by that the device (1, 1', 1'', 1''') has a central power supply (16) for the respective control circuit devices (7). [7] Device according to one of the preceding claims, characterized by that the vacuum cooling station (5) has at least one drive device for linear and / or non-linear movement of the vacuum cooling chambers (6) along the cooling section (a). [8] Device according to claim 7, characterized bythat the drive device has opposite drive units (19a, 19b) for moving respective chamber halves (6a, 6b) of the vacuum cooling chambers (6). [9] Device according to one of the preceding claims, characterized by that the vacuum cooling chambers (6) have a chamber wall in the closed state which is formed by a product conveyor (18). [10] Device according to one of the preceding claims, characterized by that the respective vacuum cooling chambers (6) along the cooling section (a) can be locked. [11] Device according to one of the preceding claims, characterized by that the device (1, 1', 1'', 1''') has a conveyor device (27) for the continuous supply of products (P) into the vacuum cooling station (5). [12] Packaging system (A) with a baking device (3), a device (1, 1', 1'', 1''') according to one of the preceding claims and with a tubular bag machine (4). [13] Method for vacuum cooling of products (P) accommodated in continuously moving vacuum cooling chambers (6), characterized by that each vacuum cooling chamber (6), while it is moved along a cooling section (a) together with at least one product (P) accommodated therein, is operated by means of a separate control circuit device (7) designed thereon for dynamic vacuum pressure generation. [14] Method according to claim 13, characterized by that the control circuit devices (7) each wirelessly receive a vacuum target pressure gradient (V) as a reference variable for dynamic vacuum pressure generation. [15] Method according to claim 13 or 14, characterized by that the vacuum target pressure gradients (V) are formed as a function of a temperature (C) of the products (P) to be cooled.

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