DE102014019829B3 - Process for monitoring the weight of the packaging (TARA) of a product chain and changes in an X-ray device - Google Patents

Abstract

Method for monitoring the weight of the packaging (TARA) of a product chain and / or for monitoring changes in an X-ray device, characterized in thata) using a X-ray device determines a control value for a TARA region (K) in which no product is located and c) the control value for a TARE region (K) is evaluated in order to identify inadmissible deviations from a limit value.

Description

The invention relates to a method for monitoring the weight of the packaging (TARA) of a product chain and changes in an X-ray device. Such processes are found among others application in the food industry in the manufacture of prepackages. Tubular bags are usually used as enveloping packaging (for example, chips bag).

These tubular bags consist of a thin film, which is unrolled from a roll first as a long flat sheet, then folded and closed on one side (fold). The tube created in this way is then closed on the underside, so that a fillable sack or pouch results. This is filled with the product to be packaged and then also closed on a dividing line serving as the top.
The top closure of the first package also serves as the bottom closure for the subsequent second package. The sealed first tubular bag can then be separated from the following strand, that is to say from the second bag, and processed individually.

For further processing, for example, an inspection and control of the tightness, the labeling or the content of the bags can be considered. The content of the bag, ie the mass of product contained in the bag, is usually checked by weighing the separated bags. The examination for impermissible impurities is carried out using metal detectors or X-ray inspection devices. The analysis of the labeling on the bag can be carried out using image recognition (barcode scanner, etc.).

The entire procedure of product filling and bag inspection can be carried out in separate machines and systems or essentially carried out in a compact filling / packaging / inspection machine.

In some cases it is advantageous or desirable not to separate the bags immediately after filling them, but to process them further as a coherent strand or chain of products. In this case, the packaging is in the form of a coherent product chain consisting of filled and closed tubular bags.

If the filled tubular bags are still available as a coherent product chain and are to be weighed in the interconnected structure, for example to monitor, control or regulate the filling elements of the filling machine, then the precise determination of the product mass required for the filling head control in each of them Pouch required.

The measuring process requires a high level of accuracy in order to guarantee a specified or, if applicable, legally required net weight of the product mass within narrow tolerances (e.g. +/- 0.1 g).

In addition, the manufacture of industrially manufactured prepackages is usually carried out at a very high speed or very high throughput, so that the weighing must take place while it is moving, i.e. the package to be weighed is in motion during the weighing and does not stand still (dynamic weighing).

In principle, a distinction is made in dynamic weighing between continuous weighing and discontinuous weighing. Conveyor belt scales are used for continuous weighing, which determine the mass flow over time for an endless (continuous) flow of bulk material to be weighed. For discontinuous weighing, automatic scales for single weighing (so-called catchweighers) and automatic checkweighers (so-called checkweighers) are used, which are able to determine the individual weight values of discrete (separate) individual packs or containers.

When examining the weight of an interrelated product chain mentioned above, however, the weight of the product in the individual pouches can disadvantageously be determined neither with conveyor belt scales, nor with checkweighers or catchweighers, since the contiguous adjacent pouches exert mechanical coupling forces on one another, which due to this “force shunt” “Lead to impermissible measurement deviations.

The reason for this is that a conveyor belt scale can only determine a mass flow as the measurement result, the course of which, however, only allows rough conclusions to be drawn about the individual weight in the individual bags. Checkweighers and catchweighers as discontinuously weighing scales, on the other hand, usually only expect a single, separate (discrete) package to be weighed on the scale platform and, due to the "force shunt" between the adjacent bags in the product chain, can also only provide inaccurate measurement results.

The situation is made even more difficult if the weighing device, as the sole control measuring device in the production of prepackages, is to guarantee 100% control and comply with the legal requirements. Then this weighing device must have an official type approval, and the series device must pass a regularly recurring measurement test (re-verification). In addition to the high measurement accuracy, this also requires a high reproducibility of the measurements.

From the US2010 / 00551513 A1 and the GB 2 453 098 A Methods for monitoring changes in an x-ray device are known.

The present invention is therefore based on the object of providing a method and a device for carrying it out which enables the weight of the packaging (TARE) of a product chain to be monitored with high accuracy and speed.

This object is achieved according to the invention with a method with the features of claim 1 and with a device with the features of claim 8.

In the sense of the invention, a x-ray represents a x-ray with a radiation source (in particular an x-ray source) and inspection with a radiation-sensitive detector, in particular a camera.

In the following, the term weight commonly used in language and trade, such as gross or total weight and net weight or net weight of a weighing good or product, packaging weight (TARE), etc., is used, although the physically correct term would be mass.

The following procedure can be partial (semi-automatic) or completely manual or preferably automatic e.g. by a controller, in particular by an evaluation and / or control device. In addition, further processing steps, such as sorting, classifying, discharging (or the control of corresponding devices such as sorting, classifying device, etc.) can be carried out as a function of the values determined according to the invention.

According to the invention, a product chain consisting of a plurality of connected (mechanically coupled) product areas (preferably each product chain) is both weighed overall ( _{total gross} weight) and also screened overall. Each product chain is preferably weighed (as every time). As an alternative to this, the total weight ( _{total gross} weight) can be determined by forming a reference value (for example gray value) by weighing it once and comparing each product chain only with this reference value. As a result of the product chain being X-rayed with an X-ray device, values (gray values) are determined which correspond to that X-ray radiation which penetrates a defined area of the product chain or the entire product chain, ie has not been absorbed by the product or the packaging material.

A total, in particular summed up or integrated, total value ( _total gray value _gross ) from the above-mentioned values can be determined line by line or also from a single x-ray image or a single x-ray image of the entire product chain. Individual values for the product chain can also be obtained line by line or from a single x-ray of the entire product chain (by means of image evaluation).

By simply dividing _{(total gross} weight / gray level _{total gross),} for the Chain of a rough reference value Ref _gross in the unit [grams per gray value] to be determined. However, this does not take into account the density differences between the product and the packaging material. The product itself can also be made up of different materials or cereals (food), for example bags with bag soup (with pasta, peas, pieces of meat, etc.).

Furthermore, according to the invention, areas with a single product (product areas) contained therein are specified or selected by evaluating the determined values. Such a selection can be made, for example, via a detected sudden increase or decrease in the values determined. In the case of a product stream moving in the longitudinal direction of the product chain with an essentially constant width of the product chain, such a (product) area can be present as a longitudinal section. Of course, it is also conceivable to determine any flat area (envelope curve or outline including the individual product by means of image evaluation) or (in particular in the case of a previously known position and / or dimension of the product).

Likewise, the position of a straight dividing line between two adjacent packagings or the distance between two products can be determined or determined by evaluating the values obtained, in order to be able to distinguish individual (packaged) products from one another. For example, it is conceivable to create a dividing line (separation is detected and (logical) dividing line (logical packaging)) based on an analysis of the gray values obtained (half the distance between adjacent maxima or from areas above a certain value, possibly including averaging, etc.) detect or define and on this basis define areas (bag region) with (or without) the product contained in each. Such a defined dividing line does not have to match an actual, existing seam, in particular a sealed seam.

After subdivision of the product chain into product areas, according to the invention, a value (gray value _product area / _gross ) for each area with product (pouch region) or each "logical" packaging by adding up or integrating the values obtained, in particular gray values, from dividing line to dividing line ( or within an envelope).

ermittelt werden.According to the invention, a weight of the individual area with the product contained therein (weight _{product area gross} ) can be derived from the relationship from the aforementioned values $${\text{Weight}}_{\text{Gross product area}}=\frac{{\text{gray value}}_{\text{Gross product area}}}{{\text{gray value}}_{\text{Total brood to}}}\times {\text{Weight}}_{\text{Total brood to}}={\text{gray value}}_{\text{Gross product area}}\times {\text{Ref}}_{\text{Gross}}$$

be determined.

If the weight of the packaging material is very much smaller than the net weight of the product in the product area, then the gross weight weight _product area gross determined by the method according to the invention can be regarded as a sufficient approximation as the net weight (weight _{product area} net) of the product. This assumption can be made for the individual product area (one chamber of a multi-chamber packaging or a single chamber packaging) or for the entire product chain.

According to the invention, other details of a net filling quantity, such as a net volume of the product contained in a package, can also be obtained from the net weight determined. Such information can easily be obtained from the net weight determined by means of conversion using known parameters of the product chain. For example, a net volume with a predetermined, preferably homogeneous, product density can be obtained in a simple manner by multiplication with the net weight determined.

The method according to the invention preferably also enables the net filling quantity of an individual product area in a product chain with a plurality of connected (mechanically coupled) product areas to be determined while such a product chain is in motion and further processing steps follow a filling and closing process. In a production line, quality assurance measures, such as inspection for foreign bodies, contamination, labeling control, etc., can follow, the method according to the invention being integrated into an arbitrary position in the production line (as an integral part thereof) after filling and the presence of a product chain, or as an independent inspection device can be trained.

In a further embodiment of the invention, the weight of the product area without product (TARA weight of a product area) weight _{TARA can be} known or determined. Also, the tare weight might be already known the chain of products (weight _{GesamtTA RA)} or be determined.

bzw. $${\text{Gewicht}}_{\text{GesamtNetto}}={\text{Gewicht}}_{\text{Gesamtbrutto }}-{\text{Gewicht}}_{\text{GesamtTARA}}$$

In weiterer Ausgestaltung der Erfindung kann das Gewicht des Verpackungsmaterials (Gewicht_TARA /L) pro Längeneinheit (z.B. in Gramm pro Meter) bzw. pro Flächeneinheit (z.B. in Gramm pro Quadratzentimeter) vorbekannt sein oder ermittelt werden. Das Gewicht des einzelnen Produktbereichs ohne Produkt (Gewicht_TARA) kann damit aus dem Gewicht_TARA/L und der detektierten Fläche des Produktbereichs bzw. der detektierten Gesamtfläche der Produktkette (oder deren Längen bei konstanter Breite (Länge_{Produktbereich} bzw. Länge_Gesamt)) berechnet werden. Die Fläche bzw. Länge kann bevorzugt mittels der Röntgendurchleuchtung (und entsprechender Bildauswertung) bestimmt werden. Alternativ kann aber auch ein optischer Sensor, z.B. eine Lichtschranke oder eine optische Kamera, verwendet werden. $${\text{Gewicht}}_{\text{TARA}}=\frac{{\text{Gewicht}}_{\text{TARA}}}{L}\times \text{Fläche des Bereiches}$$

$$\text{Fläche des Bereich}={\text{Länge}}_{\text{Produktbereich}}\times \left(\text{konstante}\right)\text{Breite}$$

Das Nettogewicht des in einer Verpackung befindlichen Produkts (Gewicht_{ProduktbereichNetto}) lässt sich wieder aus der Differenz des Bruttogewichts (Gewicht_{ProduktbereichBrutto}) und dem Gewicht der Verpackung ohne Produkt (Gewicht_TARA) berechnen. $${\text{Gewicht}}_{\text{ProduktbereichNetto}}={\text{Gewicht}}_{\text{ProduktbereichBrutto}}-{\text{Gewicht}}_{\text{TARA}}$$

In einer weiteren Ausgestaltung der Erfindung wird mindestens eine Unterregion (z.B. rechteckförmig) ohne Produkt innerhalb der Produktkette vordefiniert (TARA-Region) und hierfür einen Grauwert bzw. eine Grauwertzahl (Grauwert_RegionTARA) und die Fläche der TARA-Region Fläche_RegionTARA ermittelt (Im Folgenden werden Grauwertzahl und Grauwert gleichartig verwendet). Bevorzugt können auch mehrere TARA-Regionen definiert und deren mittlere Grauwertzahl ermittelt werden. Hieraus kann mittels Division ein Grauwert_TARA in Abhängigkeit wenigstens eines Parameters der Abmessung (vorzugsweise der Länge oder der Fläche) gebildet werden. In contrast to the approximation explained above, the net weight of the _product in a package (weight of _{product area} net) or the net weight of the product _chain ( _total weight _net ) is now determined from the difference between gross weight and a specified or determined TARE weight. $${\text{Weight}}_{\text{Net product area}}={\text{Weight}}_{\text{Gross product area}}-{\text{Weight}}_{\text{TARA}}$$

respectively. $${\text{Weight}}_{\text{total net}}={\text{Weight}}_{\text{total gross}}-{\text{Weight}}_{\text{GesamtTARA}}$$

In a further embodiment of the invention, the weight of the packaging material (weight _TARA / L) per unit length (for example in grams per meter) or per unit area (for example in grams per square centimeter) can be known or determined. The weight of the individual product area without product (weight _TARA ) can thus be calculated from the weight _TARA / L and the detected area of the product area or the detected total area of the product chain (or their lengths at constant width (length of _{product area} or _total length)) , The area or length can preferably be determined by means of X-ray fluoroscopy (and corresponding image evaluation). Alternatively, however, an optical sensor, for example a light barrier or an optical camera, can also be used. $${\text{Weight}}_{\text{TARA}}=\frac{{\text{Weight}}_{\text{TARA}}}{L}\times \text{Area of the area}$$

$$\text{Area of the area}={\text{length}}_{\text{product range}}\times \left(\text{constant}\right)\text{width}$$

The net weight of the _product in a packaging (weight of _product area _net ) can be calculated again from the difference between the gross weight (weight of _product area gross) and the weight of the packaging without product (weight _TARE ). $${\text{Weight}}_{\text{Net product area}}={\text{Weight}}_{\text{Gross product area}}-{\text{Weight}}_{\text{TARA}}$$

In a further embodiment of the invention, at least one sub-region (for example rectangular) without a product is predefined within the product chain (TARA region) and a gray value or a gray value number (gray value _RegionTARA ) and the area of the TARA region area _{RegionTARA are} determined for this (hereinafter gray value number and gray value are used equally). Preferably, several TARA regions can also be defined and their average gray scale number can be determined. From this, a gray value _TARA can be formed by division as a function of at least one parameter of the dimension (preferably the length or the area).

The definition of the sub-region can exist in different variants before analysis of the gray values obtained and can be changed to an expected value range during an evaluation by means of a causality check. In addition, it is also conceivable to define a TARE region yourself by analyzing the gray values (analogous to the definition of the product areas) (using image evaluation or threshold value analysis, e.g. an area with constant low values, i.e. minima or falling below a gray value threshold value).

$${\text{Gewicht}}_{\text{TARA}}={\text{Gewicht}}_{\text{RegionTARA}}\times \frac{{\text{Fläche}}_{\text{Produktbereich}}}{{\text{Fläche}}_{\text{RegionTARA}}}$$

If the weight ( _RegionTARA weight) of the previously selected (guaranteed product-free) TARA region is known, or if it was determined, for example, by multiplying the gray value number ( _RegionTARA gray value) by the reference (Ref _Gross ), then the TARA weight of the entire bag can be determined be calculated. This takes place via the ratio of the area _{TARE region of} the TARE region to the area _product area of the product area in the X-ray image, and is permissible because a packaging material representing TARA is also present around the product in the area with product (product region). $${\text{Weight}}_{\text{RegionTARA}}={\text{Ref}}_{\text{Gross}}\times {\text{gray value}}_{\text{RegionTARA}}$$

$${\text{Weight}}_{\text{TARA}}={\text{Weight}}_{\text{RegionTARA}}\times \frac{{\text{area}}_{\text{product range}}}{{\text{area}}_{\text{RegionTARA}}}$$

Die bisher genannten Methoden vernachlässigen, dass das anfangs ermittelte Gesamtgewicht der Produktkette (Gewicht_Gesamtbrutto) und der Gesamtgrauwert der Produktkette (Grauwert_Gesamtbrutto) ein Gemisch aus dem Produkt und dem Verpackungsmaterial darstellen, welche aber unterschiedliche Dichtewerte aufweisen. If a (preferably one-off) reference measurement with a TARE section of an empty package of any dimension (e.g. packaging snippets) could be used to determine both its weight ( _Section TARE section weight) and its gray value (TARE _section gray value) and area (or length), In order to improve the TARE determination, the more suitable Ref _TARE can be used instead of the _gross ref. $${\text{Ref}}_{\text{TARA}}={\text{Weight}}_{\text{AbschnittTARA}}{\text{/Weight}}_{\text{AbschnittTARA}}$$

The methods mentioned so far to neglect that the first total weight determined representing a mixture of the product and the packaging material of the chain of products (weight _{total gross)} and the total gray value of the product chain (gray value _{total gross),} which have but different density values.

In a preferred embodiment of the invention, the TARE weight of the entire product _chain ( _{total TARE} weight) is determined.

This can be done, for example, by the weight of the packaging material (weight _{length TARA} ) per unit length ( _e.g. in grams per meter) or per unit area (e.g. in grams per square centimeter) is known or determined, this with the detected area _total area of the product chain ( or whose length length _total with constant width) is multiplied, and from this the TARE weight of the entire product _chain (weight _{chain TARE} ) is calculated. The area or length of the product chain can preferably be determined by means of X-ray fluoroscopy (and corresponding image evaluation). $${\text{Weight}}_{\text{GesamtTARA}}={\text{Weight}}_{\text{LängeTARA}}\times {\text{length}}_{\text{total}}$$

Danach kann das ermittelte Nettogewicht der gesamten Produktkette (Gewicht_GesamtNetto) zu korrekten Anteilen auf die einzelnen Beutel aufgeteilt werden. Dies erfolgt erfindungsgemäß durch eine einfache Verhältnisrechnung. Die aufsummierten Grauwerte der Beutel-Region (Grauwert_{produktbereichlBrutto}) werden ins Verhältnis gesetzt zum Gesamtgrauwert der Produktkette (Grauwert_Gesamtbrutto). $${\text{Gewicht}}_{\text{ProduktbereichNetto}}={\text{Gewicht}}_{\text{GesamtNetto}}\times \left({\text{Gewicht}}_{\text{ProduktbereichBrutto}}{\text{/Grauwert}}_{\text{Gesamtbrutto}}\right)$$

Diese Methode verwendet nicht mehr den möglicherweise fehlerbehafteten groben Referenzwert Ref_Brutto, vernachlässigt bei der Integration des Grauwertes für jeden Beutel aber ebenfalls, dass das Produkt und das Verpackungsmaterial unterschiedliche Dichtewerte aufweisen. Denn in der Produktregion überlagert sich das Produkt mit der unteren und der oberen Verpackungsfolie.The net weight of the product _chain ( _total weight _net ) can then be calculated from the difference between the gross weight of the product chain ( _total weight _gross ) and the TARE weight of the product chain ( _total weight _TARE ). $${\text{Weight}}_{\text{total net}}={\text{Weight}}_{\text{total gross}}\times {\text{Weight}}_{\text{GesamtTARA}}$$

The net weight of the entire product _chain (total net weight) can then be distributed to the individual bags in correct proportions. According to the invention, this is done by a simple ratio calculation. The total gray values of the bag region (gray value _{product range} / _gross ) are related to the total gray value of the product chain (gray value _{total gross} ). $${\text{Weight}}_{\text{Net product area}}={\text{Weight}}_{\text{total net}}\times \left({\text{Weight}}_{\text{Gross product area}}{\text{/ Gray value}}_{\text{total gross}}\right)$$

This method no longer uses the possibly incorrect gross reference value Ref _Gross , but also neglects when integrating the gray value for each bag that the product and the packaging material have different density values. Because in the product region, the product overlaps with the lower and the upper packaging film.

In a further preferred embodiment of the invention, therefore, the x-ray image is normalized before the gray value (gray value _{product area gross} ) of the bag is integrated.

As described above, the TARE weight of the entire product _chain ( _{total TARE} weight) is first determined.

For this purpose, at least one sub-region of at least one package is predefined again (TARE region) and for this a gray value number (gray value _RegionTARA ) is determined depending on at least one parameter of the dimension and the area area _RegionTARA . Preferably, several TARA regions can also be defined and their average gray scale number can be determined.

The definition of the sub-region can exist in different variants before analysis of the gray values obtained and can be changed to an expected value range during an evaluation by means of a causality check. In addition, it is also conceivable to define a TARA region yourself by analyzing the gray values (for example, area with constant low values, i.e. minima).

$${\text{Gewicht}}_{\text{GesamtTARA}}={\text{Gewicht}}_{\text{RegionTARA}}\times \frac{{\text{Fläche}}_{\text{Gesamt}}}{{\text{Fläche}}_{\text{RegionTARA}}}$$

Falls vorab aus einer (einmaligen) Referenzmessung mit einem TARA-Abschnitt einer leeren Verpackung von beliebiger Dimension sowohl deren Gewicht (Gewicht_{AbschnittTARA}) als auch deren Grauwert (Grauwert_{AbschnittTARA}) und Fläche (bzw. Länge) ermittelt werden konnten, so kann zur Verbesserung der TARA-Bestimmung anstelle des Ref-Brutto der besser geeignete Ref_TARA verwendet werden. $${\text{Ref}}_{\text{TARA}}={\text{Gewicht}}_{\text{AbschnittTARA}}{\text{/Grauwert}}_{\text{AbschnittTARA}}$$

Anschließend wird das Nettogewicht der Produktkette (Gewicht_GesamtNetto) aus der Differenz des Bruttogewichts der Produktkette (Gewicht_Gesamtbrutto) und dem TARA-Gewicht der Produktkette (Gewicht_GesamtTARA) berechnen werden. $${\text{Gewicht}}_{\text{GesamtNetto}}={\text{Gewicht}}_{\text{Gesamtbrutto}}-{\text{Gewicht}}_{\text{GesamtTARA}}$$

In bevorzugter Ausgestaltung der Erfindung kann anschließend eine Normierung des Röntgenbildes ausgeführt werden. Hierzu kann man z.B. die mittlere Grauwertzahl der TARA-Region(en) vom gesamten Röntgenbild subtrahieren, und dann z.B. alle entstandenen negativen Grauwertzahlen verwerfen (löschen). Man erhält dann ein normiertes Röntgenbild, welches nur noch aus reinen dem Produkt zugeordneten Grauwertzahlen besteht. If the weight ( _RegionTARA weight) of the previously selected (guaranteed product-free) TARA region is known, or was determined, for example, by multiplying the gray value number ( _RegionTARA gray value) by the reference (Ref _Gross ), then the TARA weight of the entire product chain can subsequently be used _{Total TARE} weight can be calculated. This takes place via the ratio of the area _{TARE region of} the TARE region to the _total area of the product chain in the X-ray image, and is permissible because a packaging material representing TARE is also present around the product in the area with product (product region). $${\text{Weight}}_{\text{RegionTARA}}={\text{Ref}}_{\text{Gross}}\times {\text{gray value}}_{\text{RegionTARA}}$$

$${\text{Weight}}_{\text{GesamtTARA}}={\text{Weight}}_{\text{RegionTARA}}\times \frac{{\text{area}}_{\text{total}}}{{\text{area}}_{\text{RegionTARA}}}$$

If from a (one-time) reference measurement with a TARE section of an empty package of any dimension both its weight ( _Section TARE section weight) and its gray value (TARE _section gray value) and area (or length) could be determined, then the TARA determination can be used instead of the gross ref of the more suitable Ref _TARA . $${\text{Ref}}_{\text{TARA}}={\text{Weight}}_{\text{AbschnittTARA}}{\text{/ Gray value}}_{\text{AbschnittTARA}}$$

The net weight of the product _chain ( _total weight _net ) will then be calculated from the difference between the gross weight of the product chain ( _total weight _gross ) and the TARE weight of the product chain ( _total weight _TARE ). $${\text{Weight}}_{\text{total net}}={\text{Weight}}_{\text{total gross}}-{\text{Weight}}_{\text{GesamtTARA}}$$

In a preferred embodiment of the invention, the X-ray image can then be normalized. To do this, you can, for example, subtract the mean gray scale number of the TARE region (s) from the entire X-ray image and then, for example, discard (delete) all negative gray scale numbers that have arisen. A standardized x-ray image is then obtained, which only consists of pure gray value numbers assigned to the product.

The previously determined net weight of the entire product _chain (total weight _net ) can then be distributed to the individual bags or product areas in correct proportions.

According to the invention, this is done by a simple ratio calculation. The total gray values of the (standardized) product area (gray value _{product area} standardized) are related to the (standardized) total gray value of the product chain. However, the original gray value ( _{total gross} value gray value) mixed by the product and packaging material is not used, but the newly calculated sum of all standardized gray values of the product _chain ( _total value gray value _normalized ). $${\text{Weight}}_{\text{PreduktbereichNetto}}={\text{Weight}}_{\text{total net}}\times \left({\text{Weight}}_{\text{Product range Standardized}}{\text{/Weight}}_{\text{total normalized}}\right)$$

The advantage of the solution according to the invention is that the gross total weight (for example by weighing an empty product chain or the packaging material therefor) and possibly also the total TARA weight can be determined by means of a calibrated scale (s). Then the net total weight created by digital subtraction is also calibratable and also the net weight created by digital relationship formation (percentage distribution) in the individual bags.

The scale (s) can be part of the device or can be arranged separately.

The weight can be determined before, during or after screening. Instead of using scales, the weight can also be determined by means of fluoroscopy itself, for example by means of so-called comparative X-ray weighing (where the weights of all other packs are determined by comparing the gray values with those of the reference pack by means of at least one weight reference measurement of a known reference pack.

Another advantage of the solution according to the invention is the fact that the proportionate division of the exactly determined net total weight can be derived from a single x-ray image and is independent of the calibration of the x-ray device, which may have been influenced by external influences or long-term effects.

Another advantage of this solution is that no complicated geometry analysis or surface analysis is required, but that simple geometries such as rectangles or triangles can be used. However, it is also conceivable to use an exact geometry evaluation of the border (contour) of the regions in order to achieve even more accuracy.

Another advantage of the solution according to the invention is that when using the above-mentioned TARA region (s), a control _value K _RegionTARA can be determined for this TARA region (s). $${\text{K}}_{\text{RegionTARA}}={\text{gray value}}_{\text{RegionTARA}}{\text{/Area}}_{\text{RegionTARA}})$$

The control value can be evaluated to identify impermissible deviations from a limit value and e.g. generate a warning message to the operator. The control value can serve the permanent monitoring of the TARA in the running production process and report TARA fluctuations. The change in the TARA gray values in relation to a specific TARA area does not only have to be due to a change in the thickness of the packaging material. They may also be caused by changes to the fluoroscopic device, e.g. due to fluctuations in the voltage of the X-ray tube.

If a TARA reference measurement was carried out beforehand with a known (unfilled) TARA section (see above), the control value of the TARA region K _{RegionTARA can} also be compared or related to the control _{value of} the section K _{TARA, e.g.} by generate a correction value Corr for the entire measuring arrangement. For example, the determined TARE weight of the bag or even the net weight of the bag could be multiplied by the correction value corr.

$$\text{Korr}={\text{K}}_{\text{RegionTARA}}{\text{/K}}_{\text{TARA}})$$

This correction could additionally or alternatively compare the current K _RegionTARA with older K _RegionTARA , determine a "moving average" for the TARA and enable tracking of the "moving average". $${\text{K}}_{\text{TARA}}={\text{gray value}}_{\text{AbschnittTARA}}{\text{/Area}}_{\text{AbschnittTARA}})$$

$$\text{corr}={\text{K}}_{\text{RegionTARA}}{\text{/ K}}_{\text{TARA}})$$

In the solution according to the invention, any angular errors of the x-ray geometry that may occur can be corrected in a known manner based on the precise local knowledge of the product geometry (from the x-ray image).

In practice, the solution according to the invention has given very good results for packaging material made of thin film, since the simple absorption law could be used there without problems and a constant absorption coefficient (alpha) was assumed.

In a preferred solution, however, the solution according to the invention can also be supplemented by a correction of the absorption coefficient (alpha). This correction can influence the frequency, i.e. take into account the thickness dependence of the absorption coefficient (alpha). However, it can also take other effects into account, such as the noise of the X-ray detector, the voltage change on the X-ray tube, the coating of the packaging film with e.g. metallic materials such as Aluminum (vapor deposition) and more.

The correction can work with a correction value, e.g. by determining the weight and the gray scale number of a representative bag both with and without a product.

According to the invention, the fluoroscopic device can work with several energy levels in order to improve the above-mentioned correction. (Keyword: dual energy)

According to the invention, the above-mentioned subregions can be selected as desired, that is to say also across packaging.

In a further embodiment of the invention, a plurality of subregions (TARA regions) can be predefined, as explained above. A gray _{scale number} (gray _{scale TARA} ) as a function of at least one parameter of the dimension can then be determined over all TARA regions, averaging being conceivable in particular in the case of varying individual gray values.

In a further embodiment of the invention, a plurality of product chains can be processed in parallel next to one another, so that the net filling quantity according to the invention is determined simultaneously for packaging of adjacent product chains which are not connected to one another.

Of course, it is also conceivable that a product chain not only has packaging next to one another in the form of an array (consisting of several rows and columns) not only in the direction of movement but also transversely to the direction of movement. In the case of multiple tracks, several individual scales or a common upstream or downstream scale can be used to weigh the product chains.

The invention is not restricted to a coherent product chain or a coherent array of containers, each with only one chamber or only a single product area. It is also suitable for the determination of the net filling quantity in possibly already isolated containers, which, however, have several separate, contiguous chambers or product areas (and thus a product chain with several contiguous product areas), e.g. for the main product (e.g. yoghurt) and for cereals (e.g. fruit or chocolate chips). Since such containers are formed by deep drawing from a continuous strand of a thicker continuous film and are only separated after filling, according to the known prior art, separate weighing of the unfilled container (TARA) is not possible during ongoing production, and thus also regulation of the filling process , As an alternative, the prior art could be used to switch to several weighings before and after filling the individual chambers. As a result, however, several scales or the time-consuming weighing on only one scale with a complicated logistical process in the production line are disadvantageously required.

When producing a single-chamber cup by deep drawing from a e.g. circular blank, the thickness of the deep-drawn material changes in the drawn inner regions of the blank. On the X-ray, however, the deep-drawn cup appears in the same way as the original flat round blank. The method according to the invention can therefore also be used in the case of complicated deep-drawn containers without, for example, geometrically punching out (empty) intermediate regions having to be analyzed.

Even with loose product (e.g. powder) in a tubular bag, no complex image analysis of the mostly fissured product areas is required, which would also often be strongly influenced by the energy level of the X-rays used.

Another embodiment of the invention is used when the packaging material has a strongly fluctuating thickness over its length or width. Then, according to the invention, a TARE X-ray image of the unfilled packaging is taken. This TARA x-ray image is subtracted pixel by pixel from the gross x-ray image which is subsequently illuminated when filled. For this purpose, the object must be positioned as identically as possible for the fluoroscopy. Alternatively, by using image processing and using so-called Passa marks on the product chain, a congruent assignment of the pixels in both X-ray images can subsequently be produced. This method can be used in particular in the pharmaceutical sector, where the TARE (and thus the relative thickness variation of the packaging material) is very large compared to the nominal filling quantity (net).

The method according to the invention can be used in various configurations not only for checking and monitoring (logging) the net filling quantity, but also for monitoring, controlling or regulating a device for filling, for example the filling elements of a filling device.

In order to enable a particularly high processing speed, the net weight or the net filling quantity of a product in a single packaging ( _net weight) can be determined dynamically, that is to say while the packaging or the product chain is moving. Even a non-clocked, i.e. continuous, even movement of the product chain is possible.

In the preferred embodiments of the invention explained above, the weight of the packaging without product ( _TARA weight) is automatically determined by X-ray and evaluation in order to calculate the net filling quantity and to check and / or to label it on the packaging in accordance with the specifications, in particular the pre-packaging regulation ,

In addition to or in addition to flat product chains, it is also conceivable to apply the method according to the invention to multi-layer product chains. For this purpose, an x-ray device can have a plurality of x-ray sources and detectors offset from one another in order to enable a depth representation (three-dimensional).

1. 1. Kette wiegen
2. 2. Kette durchleuchten
3. 3. Brutto Beutel bestimmen
4. 4. TARA Beutel bestimmen
5. 5. Netto Beutel berechnen
6. 6. Ggf. Korrektur ausführen

Process steps "bag" (see flow chart 5 )

1. 1. Weigh the chain
2. 2. Scan the chain
3. 3. Determine the gross bag
4. 4. Determine the TARE bag
5. 5. Calculate the net pouch
6. 6. If necessary Make correction

• 1. Kette wiegen
• 2. Kette durchleuchten
• 3. TARA Kette bestimmen
• 4. Netto Kette berechnen
• 5. Aufteilen Netto der Kette auf die Beutel
• 6. Ggf. Korrektur ausführen

Process steps "chain" (see flow chart 6 )

• 1. Weigh the chain
• 2. Scan the chain
• 3. Determine the TARE chain
• 4. Calculate the net chain
• 5. Divide the net of the chain into the bags
• 6. If necessary Make correction

Further advantageous configurations result from the dependent claims.

The invention is explained in more detail below with reference to exemplary embodiments shown in the drawing.

• 1 eine Draufsicht eines Ausschnittes einer nach dem erfindungsgemäßen Verfahren arbeitenden Produktionslinie (erstes Ausführungsbeispiel) zum Befüllen und zur Verarbeitung von Schlauchbeuteln;
• 2 eine Schnittansicht entlang der Linie I-I' in 1;
• 3 eine Draufsicht eines Ausschnittes einer nach dem erfindungsgemäßen Verfahren arbeitenden Produktionslinie (zweites Ausführungsbeispiel) zum Befüllen und Verarbeiten von Bechern;
• 4 eine Schnittansicht entlang der Linie II-II' in 3:
• 5 ein Ablaufdiagramm Variante „Beutel“:
• 6 ein Ablaufdiagramm Variante „Kette“;
• 7 eine Draufsicht auf einen Mehrkammerbecher;
• 8 eine perspektivesche Ansicht eines Mehrkammerbechers nach 7;
• 9 eine einspaltige Produktkette aus mehreren Mehrkammerbechern nach 7 und 8 und
• 10 ein Array einer Produktkette aus mehreren Mehrkammerbechern nach 7 und 8.
• 11a eine Seitenansicht einer Beutelkette (Produktkette) mit mehreren voneinander separierten (unterteilten), jedoch zusammenhängenden Beuteln,
• 11b eine Draufsicht auf die Beutelkette nach 11 a;
• 11c ein Grauwertbild der Beutelkette nach 11b;
• 11d ein korrigiertes (bereinigtes) Grauwertbild nach 11c;
• 11e ein invers dargestelltes Grauwertbild nach 11 d mit einem eingezeichneten Produktbereich und
• 11f . ein invers dargestelltes Grauwertbild nach 11 d mit eingezeichneten TARA-Regionen.

The drawing shows:

• 1 a plan view of a section of a production line working according to the inventive method (first embodiment) for filling and processing tubular bags;
• 2 a sectional view along the line I-I ' in 1 ;
• 3 a plan view of a section of a production line working according to the inventive method (second embodiment) for filling and processing cups;
• 4 a sectional view along the line II-II ' in 3 :
• 5 a flow chart of the "bag" variant:
• 6 a flowchart variant "chain";
• 7 a plan view of a multi-chamber cup;
• 8th a perspective view of a multi-chamber cup 7 ;
• 9 a single column product chain consisting of several multi-chamber cups 7 and 8th and
• 10 an array of a product chain from several multi-chamber cups 7 and 8th ,
• 11a 2 shows a side view of a bag chain (product chain) with a plurality of bags which are separated from one another (divided) but connected,
• 11b a plan view of the bag chain after 11 a ;
• 11c a gray scale image of the bag chain 11b ;
• 11d a corrected (adjusted) grayscale image 11c ;
• 11e an inverse gray value image 11 d with a marked product area and
• 11f , an inverse gray value image 11 d with marked TARE regions.

In the 1 product chain shown 1 or the product line has several contiguous, non-separated individual packages 4a - 4e (for example in the form of bags) of products contained therein 3a to 3e on. The tube formation from a film web of constant width on a roll, the filling with products, as well as the subdivision or separation (without the product chain 1 to separate) in coherent packaging by means of sealing seams (welding, pressing, etc.) is carried out in the usual way, such as in the WO 2011/050355 A1 described. For a net fill quantity, in particular net weight, of an individual packaging 4a - 4e The main problem to be identified is that the actual sealed seams 27 . 29 . 31 . 33 . 35 are welded unevenly between the individual bags and therefore the rigidity of the sealed seams 27 . 29 . 31 . 33 . 35 varies, and thus always different force effects occur between two adjacent bags. Weighing a section within the product chain 1 therefore only leads to imprecise results, for example results that do not meet the requirements of the prepackaging regulation.

According to the method according to the invention, the product chain 1 therefore by means of an X-ray device, not shown in the drawing, consisting of an X-ray source and a sensor, in particular a line sensor, so that gray values are obtained as a function of the dimension (length with constant width, area, etc.) of the product chain. For this purpose, a line sensor can, for example, be perpendicular in the drawing plane to the product flow direction B below the product chain 1 and the x-ray source above the product chain 1 be stationary so that the product chain from its beginning 51 until the end 53 completely in gray values depending on the respective longitudinal position. Of course, it is also conceivable to record the product chain in one go using a suitable sensor (camera, large film, etc.) and to obtain individual gray values per longitudinal position and / or area from the overall image (read out using suitable image processing). From the gray values obtained in the product chain 1 can add up a _{total gross} value for the entire product chain by adding up or integrating 1 be determined.

The product chain continues 1 Weighed overall by means of a weighing device not shown in the drawing and thus the weight of the product chain ( _{total gross} weight) determined.

To an X-ray, in contrast to a product 3a - 3e separation that is difficult to detect, in particular a sealed seam 41 . 43 . 45 . 47 between the individual packages 4a - 4e To define in an approximate and sufficient manner, the gray values obtained can instead be analyzed in this regard. For example, it is conceivable to maxima gray values depending on their longitudinal position (in the direction B ) in the product chain 1 to investigate. Such maxima stand for a point within the range in which a product is within the packaging 4a - 4e is located, this gray value in any case the top and bottom of the packaging including the product 3a - 3e contains.

To define a separation 41 . 43 . 45 . 47 a distance between two neighboring maxima can be determined and this can be halved. 1 shows, for example, a determined (evaluated) distance A between the (gray scale) maxima 5d and 5e so that at the position of the center of the distance A / 2 the sealed seam 47 was defined. The sealing seams are corresponding 41 . 43 , and 45 as half the distance between the neighboring (gray value) maxima 5a and 5b . 5b and 5c . 5c and 5d Are defined.

Of course, it is also conceivable for the sealing seams 41 . 43 . 45 . 47 to be defined in another way, for example by analyzing the gray values with regard to a product area and defining the seal seams 41 . 43 . 45 . 47 outside of adjacent product areas, for example by halving their distance. As shown below, is a determination of the actual position of a seal 41 . 43 . 45 . 47 for determining the most exact possible net fill quantity, in particular net weight ( _net weight), is not critical or even necessary. An undesired incorrect definition of a position of a sealed seam 41 . 43 . 45 . 47 Within an actual product area, this can be avoided as far as possible in a simple manner, or can be excluded by means of a causal check (for example, gray value level, which must not be exceeded for this purpose).

According to the length L _p the product chain 1 Sections with the respective lengths L _a, L _b . L _c . L _d and L _e Are defined. How out 1 can be seen, the section ends on the center of an actual sealing seam, such as in the case of the sealing seams 41 and 45 , fall.

The beginning 51 or the end 53 the product chain, on the other hand, is about evaluating the gray values of a product chain 1 Generally, it is easy to detect exactly by X-ray technology (first or last gray value), but due to the lack of gray values outside the product chain, there is also no need to shift defined limits for determining the most exact possible net fill quantity, in particular net weight ( _net weight) is.

About the individual packaging or packaging sections or product areas subdivided in this way 4a - 4e can over their respective lengths L _a, L _b . L _c . L _d and L _e Gray values, for example by adding up or integrating the gray values obtained, can be determined for these areas. Accordingly, there is a gray value for each section for the respective individual packaging with the product contained in the _gross value _gross . In order to include the packaging, in particular film, the x-ray device is adjusted accordingly for this.

Furthermore, the length (and position) within a respective section or product area L _a, L _b . L _c . L _d and L _e At least one sub-region (TARE region) is specified or defined, which is within the packaging area or within the area of the product chain 1 lies in which, however, there is no product 5a - 5e located. Examples of this are in 1 through TARA regions 7 . 9 . 11 . 13 . 15 . 17 . 19 . 21 . 23 specified in different positions and extensions. The products are very different in their position and dimensions 3a - 3e to understand only to illustrate different locations of TARA regions, since location and area of the products 3a - 3e usually within the respective packaging sections for product chains 1 deviate from each other to a lesser extent.

Such zones can be predefined on the basis of empirical values or can also be defined as a function of the gray values obtained for a product chain using appropriate algorithms (image evaluation). For example, areas with an essentially constant gray value can be defined as a TARE region.

Because the tubular bag or the product chain 1 not only the product region, but the entire bag is wrapped in two foils (top and bottom foil), which may overlap at the joint over the entire length. In order to take better account of the overlapped film section if necessary, it may be advantageous to arrange the TARE region transversely to the longitudinal direction so that the overlap (usually at the center line) is also recorded, preferably even over the entire width. The TARA region can possibly also be placed exactly in a sealed seam region.

However, a TARE region can also be defined across areas (neighboring packaging sections) without adversely affecting the determination of the most exact possible net fill quantity, in particular net weight (weight of _{product area} net). For this purpose, for example, the determined position of a sealed seam can be used and a TARE region can be defined in this area or projecting beyond it to a predetermined extent. Of course, it is also conceivable to determine limits for an end and a beginning of adjacent product areas as explained above and a TARA region 25 in the intermediate area - between the products 3d and 3e the product areas or packaging sections 4d and 4e comprehensive - to be defined.

A gray value is determined for the respective TARE region depending on its extent (length and / or area) and on the respective section or product area 4a - 4e with the length L _a . L _b . L _c . L _d and L _e extrapolated. In this way, a gray value of the packaging without a product (gray value _TARA ) can be determined.

For this gray value _TARA and the already determined or present values gray value _{total gross} weight and _{total gross,} according to the following equation of the specific weight of a package portion without product weight _TARA be determined. $${\text{Weight}}_{\text{TARA}}=\frac{{\text{gray value}}_{\text{TARA}}}{{\text{gray value}}_{\text{Total brood to}}}\times {\text{Weight}}_{\text{Total gross to}}$$

The respective weight of a packaging section with product weight _{product area gross} can be determined from the already determined or available values gray value _{product area gross} , gray value _{total gross} and weight _{total gross} according to the following equation. $${\text{Weight}}_{\text{product gross}}=\frac{{\text{gray value}}_{\text{Gross product area}}}{{\text{gray value}}_{\text{Total brood to}}}\times {\text{Weight}}_{\text{Total gross to}}$$

From the two values obtained in this way, the net weight weight _net or weight _{product range net of} a product contained in a packaging section can be calculated as follows: $$\begin{array}{l}{\text{Weight}}_{\text{net}}={\text{Weight}}_{\text{Gross product area}}-{\text{Weight}}_{\text{TARA}}\\ =\frac{{\text{gray value}}_{\text{Gross product area}}}{{\text{gray value}}_{\text{Total brood to}}}\times {\text{Weight}}_{\text{Total gross to}}-\frac{{\text{gray value}}_{\text{TARA}}}{{\text{gray value}}_{\text{Total brood to}}}\times {\text{Weight}}_{\text{Total brood to}}\\ =\frac{{\text{Weight}}_{\text{Total brood to}}}{{\text{gray value}}_{\text{Total brood to}}}\times \left({\text{gray value}}_{\text{Gross product area}}-{\text{gray value}}_{\text{TARA}}\right)\end{array}$$

From this net weight, weight _net or weight _{product range net} , other types of a net filling quantity can also be determined in a simple manner. For example, in the case of a liquid product, a net volume could be determined by multiplying the determined net weight weight _net by a density known for the liquid.

How out 2 the product is visible 3a within the packaging section 4a with a corresponding expansion (thickness) in the middle below the fold 61 or the overlap of the folded film 63 , In the - in 2 - Folded area shown in dashed lines 65 lies the foil 63 therefore due to the overlap in almost twice the material density.

The product 3a Left and right side areas of the packaging that are not filled can, depending on the application, be filled with air or protective gas or have a vacuum.

This in 3 and 4 The second exemplary embodiment shown shows the application of the inventive method to another type of product chain, namely a cup chain 71 , for example a six-pack of yogurt, in the form of a 3x2 array.

This mug chain 71 has two tracks or columns arranged next to each other (cup 73a - c and 73d - f ) and three rows arranged in succession (cup 73a , D; 73b . e and 73 c . f ) in the direction of the product flow B on. Here are the cups 73a - 73f as well as the packaging sections in the exemplary embodiment explained above, not separated, but connected to one another (mechanically coupled).

For the already filled and possibly already closed cups 73a - 73f Due to the mechanical connection, it is just as difficult or not possible to determine the net filling quantity of individual cups in a simple and quick manner, as in the case of the above-explained example of a tubular bag strand or a product chain 1 ,

The above statements for the first embodiment are also used here, with the only difference that the product chain 1 through a two-track or two-column cup array 71 is replaced. Because the mug 73a - 73f can be manufactured by means of deep drawing, by means of a within the peripheral cup rim 77a-f arranged (predefined or determined by means of evaluation) TARA region as well, as explained in the first embodiment, a net volume can be determined. The distinction between product area and area without product, as well as definition of subdivisions can also be made in the manner already described.

However, in the case of a somewhat more precisely defined shape (due to the deep-drawing process) of the packaging, a TARE region can be specified in a simple manner, since the position and dimensions of the edge areas 77a - 77f have only the slightest deviations and TARE regions, for example the regions 79 . 81 in an edge area 77c , can be precisely specified.

Against this are the sealed seams 29 . 31 . 33 . 35 as well as beginning 51 and end 53 subject to major deviations due to the production of a tubular bag (sealing seam inaccurate, deformed, oblique, etc.), so that the definition of a TARE region in this embodiment can be advantageous, preferably by evaluating the gray values and subsequent definition (definition) with a possible causality check.

A determined gray value for a TARE region (per length or area) can easily be extrapolated (from the ratio length TARE region to packaging length or area TARE region to packaging area) to a TARE value (gray value _TARE ) of the packaging, since the distance from product separation (sealed seam, subdivision, etc.) is known as the length of the packaging and the width of the packaging material, in particular before processing (film width before tubing or a deep-drawing process). In the preferred embodiments of the invention, the gray value for the TARA film material is thus determined at at least one TARA position, in which only the pure film portion is present (TARA region). This can be done for a known length or area, so that the TARE can then be calculated exactly for the entire bag length.

This process advantageously runs automatically, quickly and with a high degree of accuracy (for example with an accuracy of 0.1 g). Learning and periodic review of a reference value (Ref _Tare , Ref _Gross ) are therefore not absolutely necessary. The TARE is determined individually for each bag in a packaging chain or an array from the gray values. TARA fluctuations can be automatically recognized and / or corrected by changing the film thickness or the packaging geometry. The TARE is determined individually for each bag in the chain from the gray values.

Such a determination of the TARA per packaging and its consideration when determining a product net or net weight is much more precise than using a mean TARA value determined on a sample basis.

For those in 5 and 6 The flow diagrams shown for the "bag" and "chain" versions apply that the different steps outlined above for determining a net quantity or a net weight do not have to take place in a fixed time sequence. Rather, different steps can take place at different times before or one after the other. In addition, the flow diagrams are followed by 5 and 6 it can be seen that a different methodology (claimed as alternatives in claim 1) can also be used to achieve the same goal.

For the sake of simplicity, the two flowcharts are designed for the example of single-chamber bags which are connected to one another in the form of a coherent, in particular single-column chain to form a product chain. Of course, the processes shown can also be transferred to multi-chamber cups or bags, whereby the term "bag" used in the flowcharts is to be replaced by the term "product range".

• Grauwert_BeutelBrutto anstelle Grauwert _{ProduktbereichBrutto}
• Gewicht_BeutelNetto anstelle Gewicht_{ProduktbereichNetto}
• Gewicht _BeutelTARA anstelle Gewicht_TARA
• Gewicht_BeutelBrutto anstelle Gewicht_{ProduktbereichBrutto}
• Gewicht_KetteNetto anstelle Gewicht_GesamtNetto

Accordingly, in the diagrams ( 5 and 6 ) uses the following terms:

• _Gray value of _{bag gross} instead of gray value of _{product range gross}
• Weight _{bag net} instead of weight _{product area net}
• Weight _{bag TARA} instead of weight _TARA
• Weight _{bag gross} instead of weight _{product range gross}
• _{Chain net} weight instead of _{total net} weight

The processes differ essentially 5 and 6 because in the variant bag ( 5 ) a gray value of _{bag gross} or gray value of _{product area gross is} determined at an earlier point in time and the weight of _{bag net} or weight of _{product area net is} determined from the difference between the weight of _{bag gross} and the weight of _{bag TARE} or weight _TARA . For this purpose, the weight _BeutelTARA is either approximately assumed to be zero (in the event expected to be very low weight compared with weight _{bag gross)} or in the manner indicated.

In contrast, in the variant "chain" ( 6 ), As shown, determines the net weight of the chain _net weight _chain or _{total net} weight approximately, or by determination of the tare weight of the chain. As a final step, this weight _{total net} weight is _divided according to the gray value _components of the individual bags or product areas and the weight of _{bag net} or _net weight is determined from this.

In both flowcharts, the right branch shows the possibility that if a control value for the TARA region is _{not observed,} K _RegionTARA compared to a previously determined control _value K _TARA a warning can be issued to a user. In the case of such a warning, it is possible, for example, to determine a correction value Korr as a function of the deviation and, as explained above, to use it (for example to improve the accuracy).

The in 7 Multi-chamber cup shown 91 comprises, as shown in the example, two separate product areas 93 and 95 , In the product area 93 is for example as a product 97 a desired amount of yogurt, whereas separate in the range 95 as a product 99 for example cereals, fruit preparation or the like. The multi-chamber mug 91 must therefore in its different product areas 93 and 95 with different products 97 and 99 can be filled both in type and in different quantities. By means of the method according to the invention, it is now possible not only to check a cover film, but even after it has been applied, not only to check the quantity but also the type (due to different density, which is accordingly reflected in the gray values) and to use the filling production system to control a control device accordingly.

Due to the presence of several, namely shown in the example two product areas within a cup 91 can this mug 91 according to the invention as a product chain.

Of course, such multi-chamber cups, as in 7 and in perspective in 8th shown, also in the form of a single column product chain as in 9 shown, that is to say with several, for example four, contiguous cups.

Moreover, it is also like in 10 shown, conceivable that such multi-chamber cups 91 just as single-chamber cups or bags are available as an array or matrix (with several columns and several rows). As in 10 Such a matrix can consist, for example, of three columns and four rows, ie 12 multi-chamber cups 91 consist.

In order to (logically) separate the product areas within such a cup, it is possible, for example, during or after an image pattern recognition (or image processing) a straight oblique dividing line T between the two product areas 93 and 95 define. Of course, it is also possible, however, to direct the product areas, in particular via image evaluation of an overall gray value image, for example in the form of a circumferential line or envelope curve 93 and 95 to determine.

In the case of a single column product chain, as in 9 shown, adjacent cups can also by means of a straight vertical dividing line L ₁ . L ₂ . L ₃ be distinguished from one another by image evaluation or threshold value analysis of the detected gray values.

Exist as in 10 shown, several, such as three columns, the columns can in turn by means of image evaluation or threshold value analysis of the gray values by straight, horizontal lines W ₁ and W ₂ (logically or for determining the filling weight or quantity). Of course, instead of the simplified variant with straight (horizontal, vertical or oblique) dividing lines, it is also possible to use envelopes to record one product area or several product areas (e.g. two and thus one cup) as one unit. In any case, it is also the case with multi-chamber cups 91 as shown, possible for each product area 93 and 95 as well as every single cup 91 (Whether in isolation, in a single-column product chain or an array as a product chain) to capture product areas individually and preferably also a cup as a unit and to apply the method according to the invention for determining the net filling quantity, in particular the net weight, to these areas.

In 11a - 11f the method according to the invention is based on a bag chain 101 with several separate (subdivided) but connected bags 103 shown. Such chains of bags 101 can be a smaller number to a larger arbitrary number, such as between two, three, four, five, six to ten or even more, of bags 103 include.

How out 11c the product chain becomes apparent 101 illuminated in full width (top view or floor plan), whereby a typical gray value image as in 11c shown arises. Here they are in different forms with the desired product 105 (for example powder) filled and separated areas or product areas can be seen, different pixels or grayscale levels also appearing in the original image in the areas without a product. These measurement errors, which arise due to tolerances and errors, such as noise, can preferably be used before further processing Image analysis or image evaluation are corrected or adjusted so that an in 11d shown cleaned image arises.

Regardless of the actual or inverse representation, as in 11e and 11f now product areas 107 be defined using vertical (red) logical dividing lines (with constant width) between neighboring products. The dividing lines (vertical lines of the rectangle 107 ) are within a range without a product. Of course, the product areas 107 also, as shown, by a flat area 107 , for example rectangular as in 11e (shown as a red border) or as any envelope around the product 105 be defined around.

As in 11f areas without a product, for example as rectangular areas, as TARE regions 109 . 111 . 113 . 115 . 117 to determine a weight _TARA , _{total TARA} up to control _values K _RegionTARA (for TARA regions), K _TARA (for sections or product areas) as well as reference _values Ref _TARA .

LIST OF REFERENCE NUMBERS

1

chain of Custody

3a-e

Products

4a-e

individual packaging or packaging sections

5a-e

Maxima gray values

7,9,11,13,15,17,19,21,23

TARA regions

25

Cross-TARA region

27,29,31,33,35, 53

actual sealing seams

41,43,45,47

defined sealing seams (logical dividing lines)

51 = 27

Beginning of the product chain (actual first sealed seam)

53

End of product chain (actual last sealed seam)

61

fold

63

Foil (tube)

65

Fold area (dashed)

71

Cup chain or array of cups

73a-f

cups

75c

product

77c

peripheral edge area

79.81

TARA regions

91

Cavity cups

93

Product area with product 97

96

Product area with product 999

97

product

99

another product

101

bag chain

103

single bag

105

Product inside a bag

107

product range

109

TARE regions (vertical) or TARE area

111

overarching TARE regions (vertical) or TARE area

113

TARE regions (vertical) or TARE area

115

TARE regions (vertical) or TARE area

117

overarching TARE regions (horizontal) or TARE area

A

distance between 5d and 5e

A / 2

half distance for definition 41 . 43 . 45 . 47

B

Direction of movement of the product chain

T

oblique, straight dividing line between areas 93 and 95

L ₁ -L ₃

vertical, straight dividing lines between cups 91

W ₁ , W ₂

horizontal, straight dividing lines between columns of cups 91

L _p

Product chain length

L _a -L _e

defined length of packaging

I-I '

intersection

II-II '

intersection

Gray _{total gross} value

Gray value for the entire product chain

Total _gross weight

Weight of the product chain

Weight of _{product range}

Net weight of a product (within a product area without packaging or packaging material

Grayscale _{product range Gross}

Gray value of a product area with product and packaging

Weight _{Product range Gross}

Weight of a product area with product and packaging

_TARA gray value

Gray value of the product area without product

Weight _TARE

Weight of a product area without a product, i.e. Package weight

_Total weight _TARE

TARE weight of the entire product chain

Ref _gross

Reference value of the product chain ( _gross ref = weight _{total gross} / gray value _{total gross}

_Total weight _net

Net weight of the product chain

_Total weight _TARE

Weight of the product chain without product, i.e. Total weight of the packaging material in a product chain

_{Product range} length

Length of the product area

_Total length

Length of the product chain

_Total area

X-ray image of the area of the product chain

TARA region

Sub-region of the product chain without a product in it

_{Grayscale region TARA}

Gray value of the TARE region

Area _regionTARA

Area of the TARA region

Weight _regionTARA

Weight of the TARE region

Ref _TARA

Reference value of a section or product area of an empty packaging (Ref _TARA = weight _TARA / gray value _TARA )

Grayscale _{product range}

Gray values of the (standardized) product area

_{Grayscale total normalized}

calculated sum of all standardized gray values of the product chain

K _RegionTARA

Control value for TARE region (s)

K _TARE

Control value of the section or product area

corr

Correction _value (= K _RegionTARA / K _TARA )

Claims (9)

Method for monitoring the weight of the packaging (TARA) of a product chain and / or for monitoring changes in an X-ray device, characterized in that a) by means of an X-ray device, a control value for a TARA region (K _RegionTARA ) in which no product is located , is determined and c) the control value for a TARA region (K _RegionTARA ) is evaluated in order to identify impermissible deviations from a limit value. Procedure according to Claim 1 , characterized in that the control value for a TARA region (K _RegionTARA ) is determined from the ratio of a gray value number of the TARA region (gray value _RegionTARA ) to the area of the TARA region (area _RegionTARA ). Procedure according to Claim 1 or 2 , characterized in that the weight of the packaging (TARE) is continuously monitored in an ongoing production process. Method according to one of the preceding claims, characterized in that the control value for a TARA region (K _RegionTARA ) is compared with a control _{value of} a section (K _TARA ) or is related to this. Procedure according to Claim 4 , characterized in that the control value for a TARA region (K _RegionTARA ) is compared with or compared to the control _{value of} the section (K _TARA ) in order to generate a correction value (corr) for the entire measurement arrangement. Method according to one of the preceding claims, characterized in that for the correction the current control value for a TARE region (K _RegionTARA ) is compared with an older control value for a TARE region (K _RegionTARA ). Procedure according to Claim 6 , characterized in that a moving average for the TARE is determined for correction and tracking of the moving average is made possible. Device for carrying out a method according to one of the preceding claims, characterized in that a) the device comprises an X-ray device which enables a control value for a TARE region (K _RegionTARA ) to be determined, b) the device comprises an evaluation device which is designed in this way is that the control value for a TARA region (K _RegionTARA ) is evaluated in order to detect impermissible deviations from a limit value. Device after Claim 8 , characterized in that the evaluation device is designed such that the control value for a TARE region (K region _TARE ) is determined from the ratio of a gray value number of the TARE region (gray value _{Region TARE} ) to the area of the TARE region (area _{Region TARE} ).

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