Device and method for measuring a property of a gas found in an item of food packaging

Abstract

The application relates to a device for measuring a property of a gas found in an item of food packaging. The device comprises a sensor for measuring the property of the gas, wherein the sensor is designed to measure the property of the gas through the food packaging without damaging the food packaging. The device also comprises a movement unit in order to move the sensor relative to the food packaging and / or a stationary base. The application also relates to a method for measuring a property of a gas found in an item of food packaging by means of a sensor, said method comprising the steps of: providing the food packaging in a food processing line, moving the sensor relative to the food packaging and / or a stationary base into a measuring position, measuring the property of the gas through the food packaging without damaging the food packaging.

Description

[0001] Apparatus and method for measuring a property of a gas contained in a food package

[0002] The invention relates to a device for measuring a property of a gas contained in food packaging. The gas contained in the food packaging is also called the atmosphere or protective atmosphere.

[0003] It is known to create a protective atmosphere in food packaging to increase the shelf life of the food contained within the food packaging. The protective atmosphere is typically created by extracting air from the packaging and / or injecting protective gas into the packaging.

[0004] One relevant value for food shelf life, for example, is the oxygen content in food packaging, as many bacteria require oxygen to multiply. Therefore, keeping the oxygen content in food packaging as low as possible is helpful in delaying spoilage of the food inside the packaging for as long as possible.

[0005] To control the oxygen content in food packaging, it is common practice to check a certain number of packages at regular intervals to determine the oxygen content of the gas contained in the food packaging.

[0006] Typically, a format consisting of several packages is removed, for example, by a separating robot behind a packaging machine. There, a number of packages can be placed in a so-called inspection drawer, which is then removed from the packaging machine by the operator.

[0007] A measuring device is then used to pierce the film of one of the packages and measure the oxygen content within the package. These packages are then disposed of, which over a longer period of time can lead to a large amount of wasted food and significant costs.

[0008] If the measurement reveals an excessive oxygen content, the packaging used for the measurement and all packaging produced since the last good measurement are generally disposed of.

[0009] It is an object of the present invention to eliminate the disadvantages of the prior art and to provide a device which allows a property of a gas contained in a food package to be measured for control purposes and at the same time keeps the number of food packages to be disposed of and the resulting costs as low as possible.

[0010] It is also an object of the present invention to provide a method by means of which it is possible to measure a property of a gas contained in a food package for control purposes and to keep the number of food packages to be disposed of and the resulting costs as low as possible.

[0011] The object is achieved by a device having the features of claim 1 and, in particular, in that the device comprises a sensor for measuring the properties of the gas, and the sensor is designed to measure the properties of the gas through the food packaging without damaging the food packaging. Such a sensor can be obtained, for example, from the company GASPOROX. Alternatively, the OxyCheck sensor from GEA can be used.

[0012] This allows the property of the gas contained in the food packaging to be inspected to be measured without having to subsequently dispose of the food packaging. In addition, the device comprises a movement unit for moving the sensor relative to the food packaging and / or a stationary base. This allows the device to be attached to a food processing line and the sensor to be moved into multiple measuring positions by the movement unit. This makes it possible to inspect different food packaging of the same format while the format of food packaging remains in the food processing line. This has the advantage that in the case of good measurements, i.e. measurements where the measured property lies within a range defined as acceptable, no food packaging needs to be disposed of.

[0013] The invention is based on the idea of ​​providing a movable sensor to enable inspection of food packaging at different positions within a format, preferably in an automated manner. Furthermore, the measurement for monitoring a property of a gas contained in a food package is performed without damaging the packaging. Thus, inspection of all food packages of a format can be performed "in-line," i.e., without removing the food packages from the food processing line.

[0014] Advantageous embodiments of the invention can be found in the dependent claims, the description and the drawings.

[0015] The sensor is preferably designed to measure the oxygen content of the gas contained in the respective food packaging. Alternatively or additionally, the sensor can be designed to measure the nitrogen content, the carbon dioxide content, or another content of the gas contained in the respective food packaging.

[0016] According to one embodiment, the movement unit is designed to move the sensor relative to the food packaging and / or the stationary base in at least two, in particular exactly three, dimensions. This allows the sensor to be positioned, for example, above the food packaging to be inspected. If the sensor is movable in three dimensions, the sensor can be moved from above towards the food packaging and downwards. This allows the distance between the sensor and the food packaging to be precisely adjusted, which can improve the measurement result.

[0017] According to one embodiment, the movement unit comprises a first drive for moving the sensor in an X-direction. The X-direction is preferably the direction of movement of the food packaging along the food packaging line. The first drive can be designed as a linear drive. For this purpose, the first drive can comprise at least one guide element and a carriage driven to move along the guide element.

[0018] The movement unit preferably comprises a second, i.e., further, drive for moving the sensor in a Y-direction. The Y-direction preferably extends horizontally and perpendicularly to the direction of movement of the food packaging along the food packaging line. The second drive can be designed as a linear drive. For this purpose, the second drive can comprise at least one guide element and a carriage driven to move along the guide element.

[0019] Alternatively or additionally, the movement unit can comprise a third drive for moving the sensor in a Z-direction. The Z-direction preferably extends vertically and perpendicularly to the direction of movement of the food packaging along the food packaging line. The third drive can be designed as a linear drive. For this purpose, the third drive can comprise at least one guide element and a carriage driven for movement along the guide element.

[0020] According to one embodiment, the traversing unit can comprise three drives that enable linear movement of the sensor in three mutually perpendicular directions. Alternatively, the traversing unit can comprise, for example, a delta robot that enables movement of the sensor in three dimensions.

[0021] According to one embodiment, the sensor is coupled to a holding device. A suction unit, in particular with one or more suction cups, is preferably arranged on the holding device. The suction unit preferably serves to suction onto the top side of the food packaging.

[0022] According to one embodiment, the sensor comprises a suction unit. The suction unit of the sensor can comprise one or more suction cups. The suction unit of the sensor can be used to apply a tensile force in the direction of the sensor to a section of an upper side of the food packaging. Preferably, the device comprises a first suction unit and a second suction unit. The first suction unit and the second suction unit are preferably designed such that, in a first suction phase, the first suction unit initially comes into contact with an upper side of the food packaging and attracts the upper side of the food packaging. Subsequently, in a second suction phase, the second suction unit pulls on the upper side of the food packaging, preferably creating a dome which can be used by the sensor to measure the property of the gas contained in the food packaging.This allows over- and under-gassed food packaging to be detected and / or measured.

[0023] According to one variant, the sensor can be designed to measure a percentage of a component, for example oxygen, of the gas through the food packaging without damaging the food packaging. The sensor can be designed and configured to measure through a transparent part of the top film of the food packaging.

[0024] According to a further variant, the sensor can be designed to measure the gas pressure through the food packaging without damaging the food packaging. For example, the sensor can be designed to press on the top film of the food packaging from the outside and thereby detect the pressure inside the food packaging and / or whether a counterpressure decreases over time, thus indicating that the packaging has a leak.

[0025] According to one embodiment, the device comprises multiple sensors. The sensors can be configured to measure the same property in parallel, i.e., simultaneously, on two different food packages. This allows more food packages to be inspected per work cycle than with just one sensor.

[0026] Alternatively, the sensors can be configured to measure two different properties in a food package. For example, one sensor can measure the pressure in the food package, and another can measure the oxygen concentration in the food package. Preferably, the sensors are configured and set up to measure the different properties in parallel, i.e., simultaneously.

[0027] According to one embodiment, the distance between the sensors is variable. The distance can thus be adapted to the dimensions of the food packaging to be inspected. Adjusting the distance between the sensors can also be useful, for example, when a different top film is being processed whose optimal measuring point is located at a different location due to a design change. This can also be the case if the dimensions of the packaging do not change. Preferably, the distance between the sensors is automatically variable. For example, a control device can be provided which sends a signal to a servomotor depending on the packaging to be inspected, whereby the distance between the sensors is automatically adjusted.

[0028] According to one embodiment, a threshold value for a gas property used to differentiate between good and bad packaging is adjustable. This allows the operator of the food processing line to define their own threshold values. The threshold value can be manually adjustable or retrieved from a data set for a particular food product being processed or a particular food packaging.

[0029] According to one embodiment, the sensor comprises a transmitter and a receiver. The transmitter is thus preferably part of the device and not part of the food packaging.

[0030] According to one embodiment, the sensor is coupled to a print head of a printer such that the sensor and the print head can be moved together by means of the moving unit relative to the food packaging and / or the stationary base.

[0031] This allows the travel unit to be used jointly for the sensor and the print head, saving costs and space.

[0032] The invention also relates to a food processing line with a slicer, in particular a high-performance slicer, a sorting and conveying line, a robot cell and / or a feeder and a packaging machine with a device for measuring a property of a gas contained in a food package, in particular with at least one of the features mentioned above or below.

[0033] The device is preferably integrated into the food processing line in such a way that the food packaging can be inspected while passing through the food processing line. In other words, the device is designed and configured to inspect food packaging as it passes through the food processing line in a regular manner.

[0034] According to one embodiment, the food processing line comprises a display unit for indicating good packaging and / or bad packaging to a user. The display unit is preferably designed and configured to mark good packaging and / or bad packaging. For example, the display unit can be designed and configured to illuminate the good packaging and / or bad packaging with colored light. For example, all detected good packaging can be illuminated with green light and / or all detected bad packaging with red light. This allows the user to immediately and easily identify the good packaging and / or bad packaging. Alternatively, a display could indicate which food packaging items were classified by the device as good packaging and / or bad packaging.The display unit can, for example, be located after a transverse and longitudinal separation station to allow manual sorting of the defective packaging in individual pieces. Alternatively, a robot can be provided to sort the defective packaging based on provided data.

[0035] The food processing line can comprise a control device or regulating device designed to change a process variable or a process sequence of the food processing line depending on the measured property of the gas, preferably to prevent defective packaging. For example, depending on the measured property of the gas, a process parameter or a process sequence can be changed, in particular automatically, to prevent the measured property of the gas from falling below a threshold value. A change to a process variable can, for example, comprise a change to a target time, a target pressure, or another process variable. A change to the process sequence can, for example, comprise not filling food packaging positions of a format that have produced defective packaging.The change of the process parameter or the process sequence can be done automatically or with manual approval by first displaying suggestions for setting values ​​on an operator interface.

[0036] According to one embodiment, a process parameter of the sealing station or a process sequence at an insertion station is changed. The control device can preferably be configured to automatically increase a target time depending on a percentage of a component, for example, oxygen, of the gas. This can be achieved, for example, by increasing a target time during which a vacuum is still maintained in the food packaging after a target negative pressure has been reached, or by increasing a target time during which a gas valve remains open for filling the food packaging with a gas.

[0037] According to one embodiment, the control device can be configured, in particular automatically, to send a signal to a labeler or printer to change a label on the food packaging depending on the measured property of the gas in the food packaging. A change to the label on the food packaging can, for example, include a change in the best-before date or a change in a classification (A, B, or C product). The change in the best-before date or the classification can be made in stages depending on the measured property of the gas, for example, the oxygen content or the pressure of the gas.

[0038] According to one embodiment, the food processing line comprises a display unit for marking parcels of a sealing station or insertion area in which good packaging and / or bad packaging were produced. This allows the user to be easily informed about which parcels should be checked because a bad packaging was produced there. According to one embodiment, the display unit can be designed and configured to illuminate those parcels that have produced good packaging and / or bad packaging with colored light. For example, all parcels in which good packaging was produced can be illuminated with green light and / or all parcels in which bad packaging was produced can be illuminated with red light. This allows the user to immediately and easily identify which parcels have produced good packaging and / or bad packaging.Alternatively, a display could show which parcels in the sealing station or the insertion area have produced good packaging and / or bad packaging.

[0039] In order to detect defective packaging and the associated production errors as early as possible, it is advantageous if the device for measuring the properties of the gas contained in the food packaging is located downstream, immediately behind the sealing station of the packaging machine. However, it is also conceivable to integrate the device for measuring the properties of the gas contained in the food packaging into a singulation robot, for example, if there is a separation robot between the sealing station and other stations (e.g., a conveyor belt).

[0040] B. transverse cutting station and longitudinal cutting station) there is no space for it.

[0041] The invention also relates to a method for measuring a property of a gas contained in a food package by means of a sensor, comprising:

[0042] - Providing food packaging in a food processing line,

[0043] - Moving the sensor relative to the food packaging and / or a stationary base into a measuring position,

[0044] - Measuring the property of the gas through the food package without damaging the food package while the food package is in the food processing line.

[0045] In other words, the preferably sealed food packaging is inspected in the food processing line by moving a sensor for measuring a property of a gas contained in the food packaging into a measuring position, and then measuring the gas property through the food packaging without damaging the food packaging. This allows the food packaging, if declared as good packaging, to be further processed through the food processing line like a non-inspected food packaging. Thus, no waste is generated with good packaging.

[0046] According to one embodiment, moving the sensor comprises positioning the sensor above the food packaging. Positioning the sensor can comprise moving the sensor in an X direction using a first drive, for example a linear drive. Furthermore, positioning the sensor can comprise moving the sensor in a Y direction using a second drive, for example a linear drive. The linear drive can comprise a toothed belt. The X direction and the Y direction are preferably arranged perpendicular to one another. For example, the X direction can extend in the transport direction of the food processing line and the Y direction can extend horizontally perpendicular to the transport direction of the food processing line.

[0047] According to one embodiment, the movement of the sensor comprises lowering the sensor toward the food packaging. The lowering of the sensor can be effected by means of a cylinder. Preferably, the sensor is lowered vertically onto a top film of the food packaging.

[0048] According to one embodiment, the method comprises applying suction to the top film of the food packaging. Suctioning the top film can be performed using one or more suction cups. This allows a portion of the top film of the food packaging to be subjected to a tensile force in the direction of the sensor.

[0049] According to one embodiment, the method comprises a second suction action on the top film of the food packaging. The second suction action on the top film can be performed using one or more smaller suction cups. This can create a dome in which the sensor can measure the gas properties through the food packaging without damaging the food packaging. Preferably, the second suction action on the top film comprises suction action on a transparent section of the top film. This results in a more precise measurement result.

[0050] According to one embodiment, the sensor measures a percentage of a component, for example oxygen, of the gas through the food packaging without damaging the food packaging. Preferably, the sensor measures the percentage of the component of the gas through a transparent portion of the top film. According to another embodiment, the sensor measures a pressure of the gas through the food packaging without damaging the food packaging.

[0051] To avoid negatively impacting the production process of a food processing line, it is advantageous to measure the properties of the gas contained in the food packaging during a work cycle of the food processing line. It would also be conceivable to perform several measurements consecutively on different food packaging using a single sensor during a work cycle of the food processing line, provided the work cycle allows for multiple measurements.

[0052] To ensure that as many food packages as possible can be inspected during short cycle times, multiple sensors can be installed. In this case, during one cycle of the food processing line, the same gas property can be measured in parallel for two different food packages and / or two different gas properties can be measured for one food package. Preferably, the two different food packages are part of the same food package format.

[0053] According to one embodiment, food packaging is automatically classified into acceptable and unacceptable packaging based on the measured gas properties. For this purpose, a threshold value for differentiating between acceptable and unacceptable packaging can be set manually or retrieved from a data set for a particular product to be processed or a particular food packaging.

[0054] According to one embodiment, a plurality of food packaging items in formats with nxm food packaging items are produced per work cycle. In this case, the food packaging items of a work cycle are arranged at different positions in the format. Preferably, in regular operation, during a first work cycle, the test, i.e. the measurement of the property of the gas through the respective food packaging, begins with a food packaging item of a first format arranged at a first position, and during a subsequent second work cycle, the test begins with a food packaging item of a second format arranged at a second position. In other words, in regular operation, testing begins at different positions in the format in order to check as many positions as possible for production errors over time.

[0055] Preferably, the food packaging arranged in the second position is not inspected during the first work cycle. Alternatively or additionally, the food packaging arranged in the first position can not be inspected during the second work cycle. In other words, in each work cycle, a subset of the positions that were not inspected in a previous work cycle can be inspected. Preferably, the positions of the formats can be processed in a specific order during the inspection, i.e. during the measurement of the properties of the gas in the food packaging. This makes it possible to inspect each position in the format once after X work cycles during ongoing production, without having to check all positions in each work cycle. This allows process errors to be detected in all areas of a format.

[0056] The number of food packages to be measured per measurement and / or the positions at which the measurements begin can be selected in advance by the user. Alternatively, the number of food packages to be measured per measurement and / or the positions at which the measurements begin can be determined automatically by a computer program. In particular, the computer program can determine the number based on parameters such as the number of packages per format, the number of cycles after which each position must be checked at least once, or the time after which each position must be checked at least once.

[0057] In order to carry out a complete inspection of all packaging at regular intervals, the entire format can be measured after a predefinable time or a predefinable number of partially measured formats. In other words, after a predefinable time or a predefinable number of partially measured formats, each food packaging of the format can be checked with regard to the gas property to be measured. To further increase process reliability or to comply with local regulations, the method can comprise removing at least one food packaging, in particular one format of food packaging, from the food processing line. In addition to the measurement in the food processing line, a property of a gas contained in the food packaging can then be measured using a further sensor outside the food processing line.

[0058] According to one embodiment, the measurement of the gas property is performed while the food packaging is connected to other food packaging. Preferably, the measurement of the gas property is performed while the food packaging forms a format or film web with the other food packaging.

[0059] In order to minimize the personnel effort required to sort out defective packaging on the food processing line, food packaging that has been declared as defective packaging can be automatically not labeled, printed, and / or automatically sorted out, or can be labeled differently.

[0060] If a deviation from an optimal value for a gas property exceeds a first threshold but falls below a second threshold, resulting in a product with a reduced shelf life that does not need to be classified as waste, a change can be automatically made to the labeling of the corresponding food packaging. The change to the labeling on the food packaging could, for example, include a change to the best-before date or a change to the classification (A, B, or C product). The change to the best-before date or classification can be made gradually depending on the measured gas property. For example, such a product could be sold at a lower price but would not have to be disposed of.

[0061] To quantify a production defect as quickly as possible, if a food package is declared defective, the packaging machine can be stopped until all packages of the format have been inspected. This allows for immediate determination of whether the defect occurred only in one food package or affects all food packages of the format.

[0062] According to one embodiment, based on a position and a number of identified defective packages, an analysis is carried out to determine which potential sources of error need to be checked. This analysis is preferably performed automatically by the food processing line. Artificial intelligence could be used for this purpose, for example. If several packages are found to be defective, this could indicate, for example, a fault in the gassing process. If only this one food package is defective, the sealing edge could be contaminated by crumbs, or a seal could be damaged.

[0063] Preferably, based on a position and the number of detected defective packages, the device learns which positions in the format produce defective packages more frequently, i.e., which positions are to be considered critical. These positions could be targeted more frequently by the sensor, particularly automatically. It would also be conceivable to modify process parameters, particularly automatically, in such a way as to avoid position-related errors. For example, the position of a gassing nozzle or the duration of the gassing process could be changed.

[0064] According to one embodiment, each food package is marked with an individual marking. If a position-related packaging defect is detected, all markings of the food packages produced at this position since the last pass inspection can be output. This has the advantage that not all packages of a format or all formats since the last pass inspection need to be disposed of.

[0065] According to one embodiment, during at least one type of interruption of the food processing line, for example during a film change on the packaging machine, the measurement of the property of the gas is continued through the food packaging.

[0066] This allows a complete format inspection to be performed in fewer work cycles, or, in the case of longer interruptions, an entire format can be checked at once during that interruption. According to one embodiment, during interruptions with known time frames, where the time frames exceed a threshold value, the measurement of the gas properties can be continued through the food packaging. Examples of an interruption with a known time frame include changing film rolls on the packaging machine, changing product batches on the loading side of the slicer, or changing product grippers on a picking robot. These typically result in a standstill of the packaging machine and can be known at least approximately by the control system.For example, there might be a command for changing the gripper that moves the robot close to the door so that the user can easily reach the gripper, or a command that moves the film roll holder to a change position. If such a command is executed, it is known that the interruption has a known time frame that exceeds the threshold. Certain error codes can also typically be associated with longer interruptions than others, which can also trigger further testing from the next positions until the format is complete. The line control system can record these times and calculate a minimum or average time, which can then be used to make a decision. During all other interruptions, the measurement of the gas properties through the food packaging cannot be continued. This has the advantage of avoiding constant movement of the sensor during only short interruptions.

[0067] According to one embodiment, the sensor is coupled to a print head of a printer. The sensor and the print head are preferably coupled such that they can be moved together. Before or after the measurement is taken by the sensor, the food packaging can be printed using the printer. For example, a best-before date can be printed on the food packaging. To save ink, good packaging can be printed using the printer and bad packaging left unprinted.

[0068] The invention will now be described by way of example only, with reference to the accompanying drawings. In the drawings:

[0069] Fig. 1 shows a packaging machine with its various stations; Fig. 2A shows a perspective side view of a device according to the invention for measuring a property of a gas contained in a food package;

[0070] Fig. 2B is a perspective bottom view of the device of Fig. 2A;

[0071] Fig. 3A is a plan view of the device of Fig. 2A;

[0072] Fig. 3B is a bottom view of the device of Fig. 2A;

[0073] Fig. 4A is a side view of the device of Fig. 2A;

[0074] Fig. 4B is an end view of the device of Fig. 2A;

[0075] Fig. 5A is a side view of a sensor unit of the device of Fig. 2A;

[0076] Fig. 5B is a perspective view of the sensor unit of Fig. 5A;

[0077] Fig. 6A is a side view of the sensor unit of Fig. 5A without the housing; and Fig. 6B is a perspective view of the sensor unit of Fig. 5A without the housing.

[0078] The packaging machine 12 shown in Fig. 1, which operates in a transport direction T, comprises a machine frame 47. A transport chain 27, shown only schematically here at the upstream end of the machine, is guided on a left side frame and a right side frame of the machine frame 47. The two transport chains 27 together form a conveying means for a bottom film 23 pulled from a supply roll 23a.

[0079] The packaging machine 12 comprises a plurality of work stations following one another in the transport direction T, namely a forming station 11, also referred to as a deep-drawer or thermoformer, an insertion station 13 for products 10 to be packaged, a feed station 14 for an upper film 25 pulled from a supply roll 25a, a sealing station 15 for connecting the lower film 23 to the upper film 25, a labeling station 16, a transverse cutting station 17 and a longitudinal cutting station 19.

[0080] The products 10 to be packaged are, for example, food products, here in the form of so-called portions, each comprising several slices that were previously separated from a loaf- or bar-shaped food product such as sausage, cheese, ham or meat using a food slicer (not shown). A central control device 41 controls the operation of the packaging machine 12, including the aforementioned workstations. Furthermore, the packaging machine 12 is provided with an operating device 45, which includes, for example, a touchscreen, on which all necessary information can be displayed to an operator and on which the operator can make all necessary settings before and during operation of the machine.

[0081] At the forming station 11, which comprises an upper tool 11a and a lower tool 11b, depressions 29, also referred to as troughs, are formed in the bottom film 23 during a deep-drawing process. The aforementioned products or portions 10 are inserted into these depressions 29 at the insertion station 13. The insertion station 13 here comprises a so-called inserter, of which two endless conveyor belts 13a, 13b are shown. Alternatively or additionally, the insertion station 13 can comprise a robot 49, also shown schematically here, e.g., in the form of a so-called "picker," which can be designed as a delta robot with a gripper 52 comprising two scoops each jointly holding a portion 10. Such robots and their use in handling foodstuffs, in particular in inserting portions into packaging depressions, are generally known to those skilled in the art, which is why further explanations are not necessary here.

[0082] Subsequently, the bottom film 23, provided with the filled recesses 29, and the top film 25 are fed to the sealing station 15, which comprises an upper tool 15a and a lower tool 15b. These tools 15a, 15b bond the top film 25 and the bottom film 23 together. This seals the recesses 29 and thus the packages 21 formed by the top film 25 and bottom film 23. Sealing points 43, also referred to as sealing seams, running transversely to the transport direction T, are schematically indicated in Fig. 1.

[0083] Following the sealing station 15, the packages 21 are still connected by the top film 25 and the bottom film 23, and therefore still need to be separated. The transverse separation station 17 and the longitudinal separation station 19 serve this purpose.

[0084] The packaging machine 12 also has a device 50 for measuring a

[0085] Property of a gas contained in a food package 52, which is schematically illustrated in Fig. 1. The device 50 is described in more detail below with reference to Figures 2A to 6B.

[0086] The device 50 comprises a sensor 54 designed to measure a property, such as an oxygen content, of a gas in a food packaging 52 through the food packaging 52 without damaging the food packaging 52. The sensor 54 is movably arranged on a base 58 designed as a frame. The base 58 is designed and configured to be fixedly connected to a machine frame 47 of the packaging machine 12. For this purpose, a plurality of fixing means 59 (see Fig. 2A) are provided to couple the base 58 to the machine frame 47. In an assembled state, the frame of the base 58 is arranged on the packaging machine 12 and extends over a working area of ​​the packaging machine 12.

[0087] The sensor 54 is mounted on the base 58 for movement in three directions. By means of a first drive 60a, the sensor 54 is linearly movable in an X direction. The X direction runs parallel to the transport direction T. By means of a second drive 60b, the sensor 54 is linearly movable in the Y direction, i.e., in a horizontal direction perpendicular to the transport direction T. In addition, a third drive 60c (see Fig. 6A) is provided to lower the sensor 54 in a Z direction, i.e., in a vertical direction, onto the food packaging 52. For this purpose, the third drive 60c comprises an actuating cylinder.

[0088] The sensor 54 forms a sensor unit with a holding device 62 (see Fig. 6A), wherein the sensor unit can be moved relative to the base 58 by the drives 60a-60c. Two suction cups 66 are attached to the holding device 62, which together form a first suction unit 64. When the sensor unit is lowered, the suction cups 66 come into contact with an upper film of the respective food packaging 52 to be inspected and pull it towards the sensor 54. Further, generally smaller, suction cups 70 are provided on the sensor 54, which form a second suction unit 68. After the first suction unit 64 has sucked the upper film of the respective food packaging 52 towards the sensor 54, the upper film of the respective food packaging 52 comes into contact with the suction cups 70 of the second suction unit 68. These are arranged obliquely, as shown in Fig. 6A, to attract the top film so that a dome, ieA three-dimensional convex outer surface section is created in the top film. The two-stage suction makes it possible to detect and / or measure over- and under-gassed food packaging. After the measurement, the respective food packaging 52 is released, and the sensor 54 can be moved to another food packaging 52 of the same format using the movement unit 56.

[0089] By measuring the oxygen content of the gas in the food packaging 52, it can be determined, for example, whether the food packaging 52 adequately protects the food product 10 contained therein from spoilage. If this is not the case, i.e. if the food packaging 52 represents defective packaging, the food packaging 52 can be sorted out. For this purpose, a display unit 72 (see Fig. 1 ) can be provided which marks all detected defective packaging so that a user can sort out the defective packaging. For example, the display unit 72 can be arranged after the transverse cutting station 17 and the longitudinal cutting station 19. As an alternative to such a display unit, the packaging machine 12 could automatically sort out the defective packaging.

[0090] To enable efficient error analysis, the packaging machine 12 includes a display unit 74 for marking parcels of a sealing station 15 or a loading area 76 in which good packages and / or defective packages were produced. This can signal to the user which parcels experienced production problems and which parcels should therefore be inspected. Alternatively or additionally, it would be conceivable to provide the data measured by the sensor 54 to the control device 41. The control device 41 could automatically make changes to the packaging machine 12 based on the measured data in order to reduce the number of defective packages in the future. List of Reference Symbols

[0091] 10 Product forming station

[0092] 11 a Upper tool 11 b Lower tool 12 Packaging machine 13 Feeding station 13a Endless conveyor belt

[0093] 13b Endless conveyor belt 14 Feed station 15 Sealing station 15a Upper tool 15b Lower tool

[0094] 16 Labeling station 17 Cross-cutting station

[0095] 19 Longitudinal cutting station 21 Packaging

[0096] 23 Bottom film 23a Supply roll 25 Top film 25a Supply roll 27 Transport chain

[0097] 29 Recess 41 Control device 43 Sealing point 45 Operating device 47 Machine frame

[0098] 49 Robot 50 Device 52 Food packaging 54 Sensor

[0099] 56 Traversing unit 58 Base 59 Fixing device 60a First drive

[0100] 60b second drive 60c third drive 62 holding device 64 first suction unit 66 suction cup

[0101] 68 second suction unit 70 suction cup 72 display unit 74 display unit 76 insertion area

Claims

Claims 1. Device (50) for measuring a property of a gas located in a food packaging (52), comprising a sensor (54) for measuring the property of the gas, wherein the sensor (54) is designed to measure the property of the gas through the food packaging (52) without damaging the food packaging (52), and comprising a displacement unit (56) for displacing the sensor (54) relative to the Food packaging (52) and / or a stationary base (58).

2. Device according to claim 1, wherein the displacement unit (56) is designed to move the sensor (54) relative to the food packaging (52) and / or the stationary base (58) in at least two, in particular three, dimensions.

3. Device according to claim 2, wherein the displacement unit (56) comprises a first drive (60a), in particular a linear drive, in order to move the sensor (54) in an X-direction, and / or wherein the displacement unit comprises a second drive (60b), in particular a linear drive, in order to move the sensor (54) in a Y-direction, and / or wherein the displacement unit comprises a third drive (60c), in particular a linear drive, in order to move the sensor (54) in a Z-direction.

4. Device according to one of the preceding claims, wherein the sensor (54) is coupled to a holding device (62), and wherein a suction unit (64), in particular with one or more suction cups (66), is arranged on the holding device (62) in order to suck up an upper side of the food packaging (52).

5. Device according to one of the preceding claims, wherein the sensor (54) comprises a suction unit (68), in particular with one or more suction cups (70), in order to apply a tensile force in the direction of the sensor to a portion of an upper side of the food packaging, in particular wherein the suction unit (68) is designed to create a dome in the upper film.

6. Device according to one of the preceding claims, wherein the sensor (54) is designed to measure a percentage of an ingredient, for example oxygen, of the gas through the food packaging (52), in particular through a transparent part of a top film, without damaging the food packaging (52), or wherein the sensor (54) is designed to measure a pressure of the gas through the food packaging (52) without damaging the food packaging (52).

7. Device according to one of the preceding claims, wherein the device (50) comprises a plurality of sensors (54), in particular wherein the sensors (54) are designed to measure in parallel an identical property in two different food packaging (52) or two different properties in one food packaging (52).

8. Device according to claim 7, wherein a distance between the sensors (54) is variable, in particular automatically.

9. Device according to one of the preceding claims, wherein a limit value of a property of the gas used to differentiate between good packaging and bad packaging is adjustable, in particular wherein the limit value is manually adjustable or can be retrieved from a data set for a respective product to be processed or a respective food packaging (52).

10. Device according to one of the preceding claims, wherein the sensor (54) comprises a transmitter and a receiver and / or wherein the sensor (54) is coupled to a print head of a printer such that the sensor (54) and the print head can be moved together by means of the displacement unit (56) relative to the food packaging (52) and / or the stationary base (58).

11. A food processing line comprising a slicer, a sorting and conveying section, a robot cell and / or a feeder, and a packaging machine (12), comprising a device (50) for measuring a property of a gas contained in a food package (52) according to at least one of the preceding claims, wherein the device (50) is integrated into the food processing line such that the food package (52) can be inspected while passing through the food processing line.

12. Food processing line according to claim 11, wherein the food processing line comprises a display unit (72) for displaying good packaging and / or bad packaging to a user, in particular wherein the display unit (72) is designed to mark good packaging and / or bad packaging, in particular to illuminate them with colored light.

13. Food processing line according to claim 11 or 12, with a control device (41) which is designed to change a process variable or a process sequence of the food processing line, in particular of a sealing station (15), or a marking of the food packaging (52) depending on the measured property of the gas, in particular wherein the control device (41) is designed to automatically increase a target time depending on a percentage of an ingredient, for example oxygen, of the gas, for example a target time in which a vacuum is still present after reaching a target negative pressure in the food packaging (52) or a target time in which a gas valve for filling a gas into the food packaging (52) remains open.

14. Food processing line according to at least one of claims 11 to 13, with a display unit (74) for marking parcels of a sealing station (15) or a loading area (76) in which good packaging and / or bad packaging were produced.

15. Food processing line according to at least one of claims 11 to 14, wherein the device (50) for measuring the property of the gas in the food package (52) is arranged downstream immediately behind a sealing station (15) of the packaging machine (12).

16. A method for measuring a property of a gas contained in a food package (52) by means of a sensor (54), comprising: providing the food package (52) in a food processing line, Moving the sensor (54) relative to the food packaging (52) and / or a stationary base (58) into a measuring position, Measuring the property of the gas by means of the sensor (54) through the food packaging (52) without damaging the food packaging (52) while the food packaging (52) is in the food processing line.

17. The method according to claim 16, wherein the movement of the sensor (54) comprises positioning the sensor (54) above the food packaging (52), in particular wherein the positioning of the sensor (54) comprises moving the sensor (54) by means of a first drive (60a), for example a linear drive, in an X direction and by means of a second drive (60b), for example a linear drive, in a Y direction.

18. The method according to claim 16 or 17, wherein the movement of the sensor (54) comprises lowering the sensor (54) in the direction of the food packaging (52), in particular wherein the lowering of the sensor (54) is effected by a cylinder.

19. Method according to at least one of claims 16 to 18, wherein the method comprises sucking a top film of the food packaging (52), in particular by means of one or more suction cups (66), in order to apply a tensile force in the direction of the sensor (54) to a portion of the top film of the food packaging (52).

20. The method according to claim 19, wherein the method comprises a second suction of the top film of the food packaging (52), in particular by means of one or more suction cups (70).

21. Method according to at least one of claims 16 to 20, wherein the sensor (54) measures a percentage of an ingredient, for example oxygen, of the gas through the food packaging (52), preferably through a transparent section of a top film, without damaging the food packaging (52), or wherein the sensor (54) measures a pressure of the gas through the food packaging (52) without damaging the food packaging (52).

22. Method according to at least one of claims 16 to 21, wherein the measurement of the property of the gas in the food packaging (52) is carried out during a work cycle of the food processing line.

23. Method according to at least one of claims 16 to 22, wherein during a work cycle of the food processing line, an identical property of gases is measured in parallel in two different food packagings (52) and / or two different properties of a gas are measured in one food packaging (52).

24. Method according to at least one of claims 16 to 23, wherein, depending on the measured property of the gas, an automatic division of the food packaging (52) into good packaging and bad packaging is carried out, in particular wherein a limit value for Differentiation between good packaging and bad packaging is set manually or is retrieved from a data set for a respective product to be processed (10) or a respective food packaging (52).

25. Method according to at least one of claims 16 to 24, wherein a plurality of food packaging units (52) in formats with nxm food packaging units (52) are produced per work cycle and thus food packaging units (52) of a work cycle are arranged at different positions in the format, and wherein in a regular operation during a first work cycle the testing of the food packaging unit (52) is started with a food packaging unit (52) of a first format arranged at a first position, and wherein during a subsequent second work cycle the testing of the food packaging unit (52) is started with a food packaging unit (52) of a second format arranged at a second position.

26. The method according to claim 25, wherein the food packaging (52) arranged in the second position is not checked during the first work cycle, wherein the food packaging (52) arranged in the first position is not checked during the second work cycle and / or wherein the positions of the formats are processed in a specific order.

27. Method according to at least one of claims 25 or 26, wherein a number of food packages (52) to be measured per measurement / test and / or the positions at which the measurements / tests are started are selected in advance by the user.

28. Method according to at least one of claims 25 to 27, wherein the entire format is measured after a predefinable time or a predefinable number of partially measured formats.

29. The method according to at least one of claims 16 to 28, further comprising: Removing at least one food packaging (52), in particular a format of food packaging (52), from the food processing line and Measuring a property of a gas contained in the food packaging (52) by means of a further sensor outside the food processing line.

30. Method according to at least one of claims 16 to 29, wherein the measurement of the property of the gas is carried out while the food packaging (52) is connected to other food packaging (52), and in particular forms a format or a film web with the other food packaging (52).

31. Method according to at least one of claims 16 to 30, wherein food packaging (52) which has been declared as defective packaging is automatically not labelled or printed or is labelled or printed differently and / or is automatically sorted out.

32. Method according to at least one of claims 16 to 31, wherein, if a food package (52) is declared as defective packaging, the packaging machine is stopped until all packages of the format have been checked.

33. Method according to at least one of claims 16 to 32, wherein, based on a position and / or a number of detected defective packaging, it is analyzed which possible sources of error are to be checked and / or wherein, based on a position and / or a number of detected defective packaging, the device learns which positions in the format produce defective packaging more frequently and these positions are approached more frequently by the sensor.

34. Method according to at least one of claims 16 to 33, wherein each food package (52) is marked with an individual marking and wherein upon detection of a position-related packaging defect, all markings of the food packaging (52) produced at this position since the last good test are output.

35. The method according to at least one of claims 16 to 34, wherein, in the event of at least one type of interruption of the food processing line, the measurement of the property of the gas is continued through the food packaging (52).

36. The method according to claim 35, wherein during interruptions with known time frames, wherein the time frames exceed a threshold value, the measurement of the property of the gas through the food packaging (52) is continued, and in particular during all other interruptions the measurement of the property of the gas through the food packaging (52) is not continued.

37. Method according to at least one of claims 16 to 36, wherein the sensor (54) is coupled to a print head of a printer in order to move the sensor (54) and the print head together, and wherein before or after the measurement by means of the sensor (54) at least one food packaging (52) is printed by means of the printer, in particular wherein good packaging is printed by means of the printer and bad packaging is not printed.

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