EP3812344A1 - Device and method for filling a container with a filling product - Google Patents

Abstract

Device (10) and method for filling a container with a filling product, preferably a foodstuff, the device (10) comprising: a product path (1, 2, 7) for transporting and introducing the filling product into the container; a viscosity determination device (8) for determining a viscosity of the filling product in the product path (1, 2, 7); a filling pressure setting device (1a, 9) for setting a filling pressure under which the filling product is introduced into the container; and a control device (6) which is communicatively coupled to the viscosity determination device (8) and the filling pressure setting device (1a, 9) and is configured to use a viscosity-filling pressure relationship from the viscosity of the filling product determined by the viscosity determination device (8), which is a functional relationship between the viscosity and the filling pressure, to determine a target filling pressure and to control the filling pressure setting device (1a, 9) to adjust the filling pressure to the target filling pressure.

Description

Technical area

The invention relates to a device and a method for filling a container with a filling product, preferably a food. The invention is particularly directed to the filling of viscous filling products.

State of the art

Viscous filling products in the food industry, such as ketchup or mayonnaise, are mostly filled in free-jet filling machines with a rotary design. In order to be able to fill cleanly and with high accuracy, an optimal flow rate specific for the filling product must be maintained. The flow rate can be determined empirically by filling tests or directly on the filling machine with the respective filling product. The flow rate is regulated by an excess gas pressure in the product storage container, whereby the gas can be sterile-filtered compressed air or another gas, mostly inert gas. The higher the viscosity of the filling product, the greater the gas overpressure in the product storage container must be in order to set the target flow rate, and vice versa.

Various more or less suitable flow rates for a large selection of products are known from experience. Flow times for different products have also been determined empirically in laboratory tests and are available as guide values for the design of new filling machines and basic settings for filling programs and processes.

Viscosity measurements can be carried out in the laboratory with so-called rheometers. The viscosity depends, among other things, on the shear rate with which the product is applied and the temperature. The measurements therefore normally take place at given shear rates and temperatures. However, the measurement results have little relation to practice, i.e. to the conditions prevailing in ongoing production, for example with regard to temperature and temperature fluctuations, behavior of non-Newtonian fluids (e.g. thixotropy), etc., so that the values determined in the laboratory are often unsuitable for practice . For example, they are at least insufficient for creating a filling print matrix as a function of a determined product viscosity.

For each production program in the filling machine, predetermined start filling pressures are usually stored for the types of filling product, which, however, relate to a specific viscosity of the filling product. Since the viscosity of the filling products can vary greatly depending on the temperature and from batch to batch, one or more filling tests are usually carried out when starting up or even during production on the filling machine in order to determine the filling pressure required for the currently prevailing viscosity conditions and / or to correct it accordingly .

Even if the filling machines are stopped for a long time, the ideal filling pressure can shift in comparison to the last filling pressure set by the pressure control for many products with thixotropic flow properties, i.e. a time-dependent viscosity, or due to temperature-dependent viscosity fluctuations. The restart of production will therefore usually not proceed optimally, and some time and fillings will pass before the pressure is adjusted to the optimal flow rate again. In this case, the filling accuracy is impaired under certain circumstances, and it can lead to underfilled but also overfilled containers that have to be sorted out, resulting in product loss.

Carrying out filling tests to determine the viscosity-dependent optimum start-up filling pressure takes time, which must be deducted from the actual production time. The filling tests reduce the efficiency of the system.

In addition, the product in the filling machine can experience a temperature change (cooling or warming) during the time in which the filling tests are carried out, so that the values determined from the filling tests may already be out of date or only briefly when production is restarted correct and therefore need to be corrected depending on the temperature. Any corrections or checks of the same can again result in time-consuming filling tests.

If filling tests are not carried out to determine the viscosity-dependent optimal filling pressure, e.g. for the purpose of increasing the efficiency of the filling system, underfilling of the filling pressure can occur if the filling pressure is too low and overfilling of the container if the filling pressure is too high. Underfilled and overfilled containers have to be sorted out, which leads to a loss of product. In addition, in the event of overfilling it can happen that filling product escapes from the containers. This can lead to contamination of the container as well as the filling machine and any other components of the filling line. In this case, the system has to be cleaned in the meantime, which in turn leads to a loss of time and thus to a deterioration in efficiency and also to the use of cost-intensive cleaning media.

Since the viscosity is temperature-dependent and can fluctuate from batch to batch, a rigid, inflexible filling pressure and fluctuating viscosity lead to a considerable impairment of the filling accuracy.

A change in viscosity as a source of error or disruption of the filling process was identified in the DE 10 2013 100 702 A1 recognized. It is proposed therein to monitor the viscosity of the medium on the basis of the filling characteristic and the pressure curve and to check whether the viscosity is within a specified expected range. Consideration of the viscosity is also known from other filling processes, for example from WO 97/00224 A1 .

Presentation of the invention

Starting from the known prior art, an object of the present invention is to provide an improved device and an improved method for filling a container with a filling product, preferably a food, in particular to improve the performance and / or reduce the product loss.

The object is achieved by a device with the features of claim 1 and a method with the features of the independent method claim. Advantageous developments follow from the subclaims, the following presentation of the invention and the description of preferred exemplary embodiments.

The device according to the invention, also referred to herein as a "filling device", is used to fill containers with a filling product. The filling device is particularly suitable for filling filling products with a comparatively high and / or variable viscosity. The filling device is particularly preferably used in the food industry, for example for filling sauces, for example ketchup or mayonnaise, viscous beverages such as fruit juices or smoothies, syrup and the like. However, viscous products from other industrial areas, such as paints, varnishes and the like, can also be filled with the filling device set out herein.

When terms such as "container", "filling organ" and others are used in the singular herein, this is primarily for the sake of linguistic simplicity. The plural is included unless it is expressly or technically excluded.

The filling device according to the invention has a product path for transporting and introducing the filling product into the container. The product path here is the path through which the filling product flows from the last treatment step of a product preparation or product processing to the Introducing the filling product referred to in the container. The device has a viscosity determination device for determining a viscosity of the filling product in the product path. The viscosity-determining device can be implemented in different ways, as is set out below in relation to preferred embodiments. The device also has a filling pressure setting device for setting a filling pressure under which the filling product is introduced into the container. The flow rate of the filling product depends on its viscosity. In order to set an optimal flow rate and maintain it during production, a filling pressure adjustment device is therefore available that can change the filling pressure. The filling device also has a control device which is communicatively coupled to the viscosity determination device and the filling pressure setting device. The coupling can be wireless or wired and is used to transmit data, for example measurement data or data derived therefrom, control commands and the like in one or in both directions.

According to the invention, the control device is set up to determine a target filling pressure from the viscosity of the filling product determined by the viscosity determining device using a viscosity-filling pressure relationship, which is a functional relationship between the viscosity and the filling pressure, and to use the filling pressure setting device to adjust the ( actual) filling pressure to control the target filling pressure. In other words, the control device determines a suitable or optimal filling pressure from the currently determined viscosity of the filling product in the product path, using a predetermined viscosity-filling pressure relationship, and regulates this filling pressure.

This enables the efficiency of the filling device to be increased in several respects. On the one hand, filling tests at the start of production or when restarting the system after an interruption in production can be dispensed with, since the control device determines and sets a suitable filling pressure from the viscosity-filling pressure relationship immediately before the first container is filled. On the other hand, filling tests after strong or abrupt changes in the viscosity of the filling product, for example due to temperature fluctuations or different batch properties, can be dispensed with. Furthermore, when new, previously unknown filling products are put into operation, filling tests can be dispensed with due to the data collected (viscosities, densities, etc.), for example by comparing them with the current filling product data and the resulting optimal filling pressures in practice.

A filling pressure optimized in this way also contributes to a reduction or avoidance of overfilled and thus possibly contaminating containers, whereby machine stops, cleaning times and restart situations are minimized.

Product losses can also be minimized through the optimization of the filling pressure described here. The materials required for filling tests - filling product, container and the like - usually have to be discarded for reasons of hygiene and quality. By eliminating filling tests, material loss can be minimized. Furthermore, the containers rejected due to overfilling or underfilling can be minimized. Ideally, the filled containers are salable from the first round of filling, which further improves the performance of the filler.

A further technical contribution of the invention lies in an improvement of the filling accuracy through always optimal flow rates set via the viscosity-dependent filling pressure regulation. Even slight fluctuations in viscosity with simultaneous impairment of the filling accuracy can be responded to quickly, almost immediately. Substantially constant filling conditions result in a reduction in soiled containers.

The product path preferably has a product inlet, a product tank in fluid connection therewith and one or more filling elements in fluid connection therewith, the product inlet being set up to guide the filling product into the product tank, and the filling elements being set up to feed the product tank to introduce the filling product in the container accordingly. The product tank serves, for example, as an intermediate buffer for the filling product in order to ensure continuous and reliable filling operation. The product tank provides the filling product to be filled to the filling organs via corresponding product lines. The filling members are preferably each equipped with a filling valve through which the containers to be filled are filled with the filling product. In this case, the filling product is preferably introduced into the corresponding container in a free jet.

The filling device is preferably constructed in a rotary design, in which case the filling elements are installed on a carousel and the product tank can be designed as a stationary or co-rotating central boiler.

The product tank preferably has a head space above the filling product which is filled with gas, preferably sterile air or an inert gas. In this case, the filling pressure can be modified by changing the gas pressure in the head space of the product tank. For this purpose, the filling device preferably has a pressure regulator which is communicatively coupled to the control device and which is set up to regulate the gas pressure in the head space of the product tank. Furthermore, a pressure sensor can be provided which is communicatively coupled to the control device and is set up to measure the gas pressure in the head space of the product tank and the To transmit control device, whereby the regulation of the filling pressure to the target filling pressure can be carried out efficiently.

The product tank set out above is part of the product path and, together with the pressure regulator, forms a preferred, mechanically simple and reliable implementation of the filling pressure setting device by regulating the filling pressure via the gas pressure in the head space. It should be pointed out that the filling pressure can, if necessary, also be technically set and regulated in other ways, for example by means of a pump, vacuum device or the like.

The filling device preferably has a fill level sensor for determining, for example, the current fill level of the filling product in the product tank and / or a temperature sensor for determining, for example detecting, the filling product temperature in the product tank. These data can be transmitted to the control device for further processing and optimization of the filling process.

The viscosity determination device preferably has a flow measuring device and / or an inline viscometer for determining the viscosity of the filling product in the product inlet and / or a process viscometer for determining the viscosity of the filling product in the product tank. In this way, the viscosity of the filling product can be determined in a mechanically simple and reliable manner. The flow measuring device can be or comprise, for example, a Coriolis flow measuring device. The flow measuring device can also be a combined measuring device which, in addition to the mass flow in the product feed to the product tank, determines or detects other variables, such as the temperature, the specific density and / or viscosity of the filling product. If equipped accordingly, the flow measuring device can send direct data about the viscosity to the control device. Alternatively, data of equivalent physical quantities or quantities from which the viscosity can be derived or calculated can be transmitted to the control device. For example, the volume flow or mass flow can be detected by the flow measuring device and sent to the control device, the control device deriving the viscosity therefrom, for example using the Hagen-Poiseuille law.

An alternative method for determining the viscosity, which does not require a measurement of the mass or volume flow, uses the pressure drop that occurs in the product path. For this purpose, the viscosity determination device preferably has at least two pressure sensors, which are set up to detect the pressure occurring during a flow of filling product at at least two different points in the product path, the control device being set up to measure the pressure difference between the two pressure sensors to use as a measure of the viscosity of the filling product or to calculate such from the pressure difference.

With this method, i) instead of a viscosity-filling pressure relationship, a pressure difference-filling pressure relationship can be stored in the control device, so that an explicit determination, i.e. calculation or detection, of the viscosity can be dispensed with. Alternatively, ii) a pressure difference-viscosity relationship can be stored with which, in an intermediate step, a viscosity associated with the pressure difference is first determined, which is then used in a second step to determine the filling pressure. Both approaches and associated technical devices fall under the terms "viscosity determination", "viscosity determination device" and the like herein. In the first case i) an explicit determination of the viscosity in a physical unit of viscosity is dispensed with; However, since the pressure difference between the pressure transducers is proportional to the viscosity, the pressure difference can be viewed and used as a physical measure for the viscosity. For this reason, the above-mentioned pressure difference-filling pressure relationship also falls under the designation "viscosity-filling pressure relationship" here.

The control device is preferably set up to calculate the target filling pressure at the start of production and / or after an interruption in production and / or in the case of a viscosity change exceeding a threshold value from the viscosity of the filling product determined by the viscosity determining device using the viscosity-filling pressure relationship to determine. Such special phases of the filling process - start of production, interruption of production, strong or abrupt changes in viscosity, etc. - are linguistically different from a regular operation in which the filling device produces with little or no fluctuations in viscosity.

The regulation of the filling pressure from the viscosity set out here is particularly suitable for the irregular phases mentioned, in which, for example, an alternative regulating method cannot keep the flow rate within a predetermined window, or only with difficulty.

In regular operation of the filling device, regulation can also take place via the viscosity-filling pressure relationship; however, an alternative regulation can also be carried out, for example by comparing a measured or otherwise determined current flow rate with a target flow rate. Since inflexible maintenance of a preset filling pressure can lead to the flow rate fluctuating unintentionally when the viscosity changes, the filling pressure can be adjusted during ongoing production so that the actual flow rate is kept within a permissible range of the target flow rate.

The viscosity-filling pressure relationship is preferably determined empirically or experimentally. It is, for example, a product-specific, empirically determined function that indicates an optimal or at least suitable filling pressure as a function of the viscosity. Thus, a product database with empirically determined viscosity-filling pressure relationships can be stored in the control device, or the control device can access such a database. The functional relationship between viscosity and filling pressure can be stored or displayed in any way. A tabular representation is just as possible, for example, as an analytical expression, if known. In addition to an experimental or empirical determination of the viscosity-filling pressure relationship, this can also be obtained, for example, from model calculations or simulations, provided the data determined in this way are suitable for practice.

The above-mentioned object is also achieved by a method for filling a container with a filling product, preferably a food. The method comprises: transporting the filling product along a product path and introducing the filling product into the container; Determining a viscosity of the filling product in the product path by means of a viscosity determining device; Determining a target filling pressure from the viscosity of the filling product determined by the viscosity determining device using a viscosity-filling pressure relationship which is a functional relationship between the viscosity and the filling pressure; and regulating or setting the filling pressure, under which the filling product is introduced into the container, by controlling a filling pressure setting device, so that the filling pressure adapts to the target filling pressure.

The features, technical effects, advantages and exemplary embodiments that were described in relation to the device apply analogously to the method.

Thus, the product path preferably has a product inlet, a product tank in fluid connection therewith and one or more filling elements in fluid connection therewith, the filling product being transported or conducted via the product inlet into the product tank, from the product tank to the filling elements, and the filling elements Pour the filling product into the container accordingly. For the reasons mentioned above, the product tank preferably has a head space above the filling product filled with gas, preferably sterile air or an inert gas, the gas pressure in the head space in this case being regulated by a pressure regulator, whereby the filling pressure is set, preferably taking into account Measured values from a pressure transducer that measures the gas pressure in the head space of the product tank.

For the reasons mentioned above, the viscosity determining device preferably has a flow measuring device and / or an inline viscometer, which determine the viscosity of the filling product in the product feed, i.e. measure it directly or derive it from other physical quantities. As an alternative or in addition, the viscosity determination device has a process viscometer which determines the viscosity of the filling product in the product tank.

For the reasons mentioned above, the viscosity determination device preferably has at least two pressure sensors which detect the pressure occurring during a flow of filling product at at least two different points in the product path, the pressure difference between the two pressure sensors being used as a measure of the viscosity of the filling product or such is calculated from the pressure difference.

For the reasons mentioned above, the target filling pressure at the start of production and / or after an interruption in production and / or in the case of a viscosity change exceeding a threshold value is preferably determined from the viscosity of the filling product determined by the viscosity determination device using the viscosity-filling pressure relationship determined.

For the reasons mentioned above, the filling pressure is preferably regulated in a regular filling operation by an alternative control without taking into account the viscosity-filling pressure relationship, preferably by comparing the actual flow rate with a target flow rate.

For the reasons mentioned above, the viscosity of the filling product is preferably determined by the viscosity determination device in regular filling operation - this can be done continuously or at regular or uneven time intervals - with corrective action being taken in the alternative control mentioned, for example in the event of strong or abrupt changes in viscosity.

For the reasons mentioned above, the viscosity-filling pressure relationship is preferably determined empirically or experimentally. For example, a product-specific function can be determined and / or a database can be created that specifies a suitable or optimal filling pressure as a function of the viscosity.

Further advantages and features of the present invention can be seen from the following description of preferred exemplary embodiments. The features described therein can be used alone or in combination with one or more of the features set out above implemented as long as the features do not contradict each other. The following description of preferred exemplary embodiments is made with reference to the accompanying drawings.

Brief description of the figures

Figur 1

eine schematische Füllvorrichtung zum Befüllen eines Behälters mit einem Füllprodukt;

Figur 2

eine schematische Füllvorrichtung zum Befüllen eines Behälters mit einem Füllprodukt gemäß einem weiteren Ausführungsbeispiel;

Figur 3

eine schematische Füllvorrichtung zum Befüllen eines Behälters mit einem Füllprodukt gemäß einem weiteren Ausführungsbeispiel;

Figur 4

eine schematische Füllvorrichtung zum Befüllen eines Behälters mit einem Füllprodukt gemäß einem weiteren Ausführungsbeispiel;

Figur 5a

ein Diagramm, das die Viskosität als Funktion des Abfülldrucks zeigt; und

Figur 5b

eine Sequenz von Diagrammen zur Bestimmung des Abfülldrucks.

Preferred further embodiments of the invention are explained in more detail by the following description of the figures. Show:

Figure 1

a schematic filling device for filling a container with a filling product;

Figure 2

a schematic filling device for filling a container with a filling product according to a further embodiment;

Figure 3

a schematic filling device for filling a container with a filling product according to a further embodiment;

Figure 4

a schematic filling device for filling a container with a filling product according to a further embodiment;

Figure 5a

a diagram showing the viscosity as a function of the filling pressure; and

Figure 5b

a sequence of diagrams to determine the filling pressure.

Detailed description of preferred exemplary embodiments

Preferred exemplary embodiments are described below with reference to the figures. Identical, similar or identically acting elements are provided with identical reference symbols in the different figures, and a repeated description of these elements is in some cases dispensed with in order to avoid redundancies.

A device 10 for filling containers, also referred to herein as a "filling device", according to one embodiment is shown schematically in FIG Figure 1 shown. The filling device 10 is particularly suitable for filling filling products of variable viscosity. The containers to be filled are not shown in the figures.

The filling device 10 has a product tank 1 and a plurality of filling members 2 in fluid communication therewith. The filling device 10 is preferably constructed in a rotary design, in which case the filling elements 2 are installed on a carousel and the product tank 1 can be designed as a stationary or co-rotating central boiler.

The product tank 1 provides the filling product to be filled to the filling organs 2 via corresponding product lines. The filling members 2 are each equipped with a filling valve through which the containers to be filled are filled with the filling product, preferably in a free jet process. For this purpose, the containers to be filled are received in container receptacles, not shown in the figures, and placed with the container mouths below the filling valves of the filling elements 2 so that the product can be introduced into the container in a free jet. Alternatively, the container mouths can be pressed against corresponding outlet openings of the filling members 2, so that a liquid-tight and / or gas-tight contact is established between them.

The product tank 1 is supplied with the filling product to be filled into the container to be filled via a product inlet 7. The product inlet denotes a path through which the filling product flows to the product tank 1, including all areas touched by the finished, fillable filling product, ie from the last treatment step of product preparation to the entry into the product tank 1. The path through which the fill product flows from the last treatment step of product preparation to The outlet of the corresponding filling element 2 is also referred to herein as a “product path”.

The filling product is preferably a viscous fluid from the food sector, such as sauces, thick drinks, syrups and the like. In particular, seasoning sauces, for example ketchup or mayonnaise, come into consideration. However, viscous products from other industrial sectors, such as paints, varnishes and the like, can also be filled with the filling device 10 set out herein.

The product tank 1 has a head space 1a above the filling product, in which there is a gas atmosphere, the pressure and / or composition of which can change in the course of the regular operation of the filling device 10, i.e. during the filling process. There is preferably sterile air or an inert gas in the head space 1a.

To regulate the gas atmosphere in the head space 1a of the product tank 1, a gas feed line, a gas discharge line and a pressure regulator 9 coupled thereto are provided, which is set up to regulate the gas pressure in the head space 1a. The gas pressure in the head space 1a of the product tank 1, thus also the filling pressure, i.e. the pressure under which the filling product is fed to the filling members 2 and filled, can be measured via a pressure sensor 3.

The filling device 10 preferably also has a fill level sensor 4 for determining, for example detecting, the current fill level of the fill product in the product tank 1 and / or a

Temperature sensor 5 for determining, for example detection, the filling product temperature in the product tank 1.

The product tank 1 set out above is part of the product path and implements a filling pressure setting device in that the filling pressure is regulated via the gas pressure in the head space 1a. It should be pointed out that the filling pressure can, if necessary, also be technically set or regulated in other ways, for example by means of a pump, vacuum device or the like. The product tank 1 together with the pressure regulator 9 is thus a preferred technical implementation of the filling pressure setting device, but not necessarily the only possible one.

According to the exemplary embodiment of FIG Figure 1 a flow measuring device 8a on the product inlet 7, which is set up to detect the mass flow or volume flow in the product inlet 7. The flow measuring device 8a can be or comprise, for example, a Coriolis flow measuring device. The flow measuring device 8a can be a combined measuring device which, in addition to the mass flow or volume flow in the product inlet 7, determines or detects other variables, such as the temperature, the specific density and / or directly the viscosity of the filling product.

The various pickups, sensors, actuators, electronic devices and the like communicate with a control device 6. This can be done wirelessly or by wire.

The flow measuring device 8 a is set up to transmit the measurement data to the control device 6. If equipped accordingly, the flow measuring device 8 a can send direct data on the viscosity to the control device 6. Alternatively, data of equivalent physical quantities or quantities from which the viscosity can be derived or calculated can be transmitted to the control device 6. It is thus possible for the volume flow or the mass flow to be detected by the flow measuring device 8a and corresponding data to be sent to the control device 6, the control device 6 deriving the viscosity therefrom, for example using the Hagen-Poiseuille law.

The flow measuring device 8a, if it is set up to detect or otherwise determine the viscosity, or otherwise the combination of the flow measuring device 8a and the control device 6 are referred to herein as “viscosity determining device” 8. This applies in an analogous manner to the design variants set out below.

The viscosity detected in this way is used by the control device 6 as a basis for determining the filling pressure. This takes place on the basis of a viscosity-filling pressure relationship, preferably an empirically determined product database and the product-specific function (s) of the necessary, suitable or optimal filling pressure derived therefrom as a function of the viscosity.

Such a functional viscosity-filling pressure relationship is in the Figure 5a shown. The filling pressure is plotted on the x-axis and the viscosity is plotted on the y-axis. Starting from a viscosity determined in the product inlet 7, the desired filling pressure can be read off therefrom, as indicated by dashed arrows in FIG Figure 5a is shown in order to finally achieve the required target flow rate.

Of course, the functional relationship between viscosity and filling pressure can also be obtained and expressed in other ways. A tabular representation is just as possible, for example, as an analytical expression, if known. The functional dependency can be determined empirically, experimentally or, for example, from a model calculation or simulation.

The filling pressure obtained in this way is set by the pressure regulator 9 in the product tank 1. For this purpose, the gas pressure in the head space 1a of the product tank 1 is measured and transmitted to the control device 6. The control device 6 can now approximate and set the gas pressure in the head space 1a to the previously determined starting pressure by means of a suitable control algorithm. Such a control based on the viscosity-filling pressure relationship is preferably carried out for the starting filling pressure when starting, restarting or after an interruption in production

After the start of the filling process, the viscosities determined by means of the flow measuring device 8 are used in the control device 6, for example, once, several times, continuously or at specific, uniform or non-uniform time intervals, in order to determine regulations or corrections of the filling pressure based on the viscosity-filling pressure relationship to pass on to the pressure regulator 9, so that optimal production conditions are maintained.

Alternatively or additionally, the flow rate of the filling product through the filling elements 2 can be determined, for example by the control device 6, and compared with a target flow rate stored in the control device 6. If the target flow rate matches the current average flow rate, the filling pressure can be maintained; when the target flow rate If it deviates beyond the specified limits, the filling pressure can be readjusted: Flow rate too high -> filling pressure is reduced, and vice versa.

The pressure regulation is preferably carried out using a viscosity-filling pressure relationship by means of the flow measuring device 8 only at the start of production, during longer interruptions and / or with strongly changing viscosities, until the desired flow rate is reached. In this case, the filling pressure is then further regulated by the specified flow rate. However, the pressure regulation can also be carried out using a viscosity-filling pressure relationship by means of the flow measuring device 8 over the entire operation, including regular and irregular conditions.

The Figure 2 shows a filling device 10 according to a further embodiment, which differs from that of the Figure 1 The difference is that instead of a flow measuring device 8a, an inline viscometer 8b is installed in the product inlet 7. The inline viscometer 8b detects the viscosity of the filling product in the product inlet 7 to the product tank 1 and transmits the detected viscosity data to the control device 6, which controls the filling pressure based on a viscosity-filling pressure relationship, as in relation to the embodiment of FIG Figure 1 described.

The Figure 3 shows a filling device 10 according to a further embodiment, which differs from that of the Figure 1 differs in that a process viscometer 8c is installed in the process tank 1 instead of a flow measuring device 8a. While an inline viscometer 8b is installed in the product inlet 7, ie in a transport line, the process viscometer 8c is set up to detect the viscosity of the filling product in the process tank 1. The control of the filling pressure, in particular the starting filling pressure and / or any corrections during the filling process or after interruptions, takes place as in relation to the exemplary embodiment of FIG Figure 1 described.

The Figure 4 shows a filling device 10 according to a further exemplary embodiment, in which the viscosity-dependent pressure drop in systems with a flow is used to determine and control the filling pressure. For this purpose, two pressure sensors 8d and 8e are installed in the product inlet 7, which measure the pressure occurring there during the flow at two different points in the product inlet 7. The pressure difference thus determined between the pressure sensors 8d and 8e, assuming a laminar flow through the product inlet 7, is directly proportional to the product viscosity. The assumption is generally justified in the case of comparatively highly viscous products and the flow velocities occurring here.

According to Darcy-Weisbach, the pressure difference and the viscosity are related to the following fluid mechanics:

Druckverlustbeiwerte.Here, Dp _1/2 denote the pressure loss between the two pressure sensors 8d and 8e, the density p of the filling product, v the mean flow velocity, λ the pipe friction factor, L is the length of the pipeline, ie the distance between the two pressure sensors 8d and 8e, d is the Inner diameter of the pipeline and

Pressure loss coefficients.

According to the Hagen-Poiseuille law, the following applies to the fully developed laminar flow in a circular pipe: $$\lambda =64/\mathit{re}$$

Here Re denotes the Reynolds number: $$\mathit{re}=\frac{\mathit{\lambda vd}}{\eta }$$

$$\to {\mathit{\Delta }\mathit{p}}_{1/2}\sim \eta ,\rho$$

This depends on the dynamic viscosity η . It follows: $$\to {\mathit{<figure-callout\; id="1"\; label="\Delta p"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\Delta p</figure-callout>}}_{\frac{1}{2}}=\frac{32\eta }{d}+\frac{{\mathit{<figure-callout\; id="2"\; label="\rho v"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\rho v</figure-callout>}}^2}{2}{\mathit{\Sigma \varsigma }}_i$$

$$\to {\mathit{<figure-callout\; id="1"\; label="\Delta \; p"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\Delta </figure-callout>}\mathit{p}\mathit{}}_{1/2}\sim \eta ,\rho$$

ist die Produktviskosität demnach proportional zum Druckabfall bzw. zur Druckdifferenz Δp _1/2 zwischen den beiden Druckaufnehmern 8d und 8e. Zwar haben Dichteänderungen ebenfalls einen Einfluss auf den Druckverlust, doch können diese in der Regel vernachlässigt werden.With a constant flow velocity v of the system and with a constant flow diameter d and drag coefficients

is the product viscosity, therefore, proportional to the pressure drop or the pressure differential Dp _half between the two pressure sensors 8d and 8e. Although changes in density also have an influence on the pressure loss, these can usually be neglected.

So can with the in the Figure 5b depicted relationships of the filling pressure over the pressure loss can be shown and found, for example as the starting filling pressure and for any corrections, as in relation to the embodiment of FIG Figure 1 set out.

Here, i) instead of a viscosity-filling pressure relationship, a pressure difference-filling pressure relationship can be stored in the control device 6, so that an explicit determination, ie calculation or detection, of the viscosity can be dispensed with. Alternatively, ii) a pressure difference-viscosity relationship can be stored with which, in an intermediate step, a viscosity associated with the pressure difference is first determined, which is then determined in a second step for Determination of the filling pressure is used, as in relation to the embodiment of FIG Figure 1 explained.

Both approaches and associated technical devices fall under the terms "viscosity determination", "viscosity determination device" and the like herein. In the first case i) an explicit determination of the viscosity in a physical unit of viscosity is dispensed with; however, since the pressure difference between the pressure sensors 8d and 8e is proportional to the viscosity, the pressure difference can be viewed and used as a physical measure for the viscosity. Because of this, the Figure 5b The pressure difference-filling pressure relationship shown is also referred to as "viscosity-filling pressure relationship".

It should be noted that, of course, combinations of the Figures 1 to 4 Embodiments shown are possible. By using several techniques for determining viscosity, for example, the accuracy of the determination of the filling pressure can be improved or the probability of failure can be reduced.

1. 1. Ermittlung der Viskosität des Füllprodukts während des Anfüllens des Produkttanks 1 der Füllvorrichtung 10, beispielsweise im Produktzulauf 7 oder im Produkttank 1, über dazu geeignete Messgeräte, beispielsweise mittels einer Durchflussmesseinrichtung 8a mit der Möglichkeit der Viskositätsmessung, eines Inline- oder Prozess-Viskosimeters 8b, 8c oder mittels zumindest zweier Druckaufnehmer 8d, 8e zur Ermittlung des Druckabfalls im durchströmten Produktzulauf 7;
2. 2. Weitergabe der Viskositätsdaten, umfassend einen etwaig detektierten Druckabfall, an die Steuereinrichtung 6;
3. 3. Ermittlung des viskositätsabhängigen Start-Abfülldrucks aus einer in der Steuereinrichtung 6 hinterlegten Viskositäts-Abfülldruck-Beziehung;
4. 4. Einstellen des Start-Abfülldrucks an der Füllvorrichtung 10, d.h. des Gasdrucks im Kopfraum 1a des Produkttanks 1, beim Anlauf oder nach einer Unterbrechung der Produktion mittels des Druckreglers 9 und des Druckaufnehmers 3;
5. 5. Gegebenenfalls Übernahme der Druckregelung durch ein System, das die aktuelle Fließleistung mit einer Soll-Fließleistung abgleicht und den Gasdruck im Kopfraum 1a entsprechend weiterregelt;
6. 6. Gegebenenfalls bei festgestellter Viskositätsänderung, Einstellen eines neuen Abfülldrucks im Kopfraum 1a, wenn ein unter Schritt 5 beschriebenes System zur Druckregelung nicht innerhalb einer parametrierbaren Zeit einen neuen Abfülldruck einregeln kann.

In the following, exemplary methods for determining the start filling pressure at the start of production or resumption of production after a long production stop as well as for viscosity-dependent regulation of the filling pressure during production are presented:
Determination of a start filling pressure at the start of production or resumption of production after a production stop or a production interruption:

1. 1. Determination of the viscosity of the filling product during the filling of the product tank 1 of the filling device 10, for example in the product inlet 7 or in the product tank 1, using suitable measuring devices, for example by means of a flow measuring device 8a with the possibility of viscosity measurement, an inline or process viscometer 8b , 8c or by means of at least two pressure sensors 8d, 8e to determine the pressure drop in the product inlet 7;
2. 2. Forwarding of the viscosity data, including any detected pressure drop, to the control device 6;
3. 3. Determination of the viscosity-dependent starting filling pressure from a viscosity-filling pressure relationship stored in the control device 6;
4. 4. Setting the starting filling pressure on the filling device 10, ie the gas pressure in the head space 1a of the product tank 1, during start-up or after an interruption in production by means of the pressure regulator 9 and the pressure sensor 3;
5. 5. If necessary, the pressure control is taken over by a system which compares the current flow rate with a target flow rate and further regulates the gas pressure in the head space 1a accordingly;
6. 6. If necessary, if a change in viscosity is detected, setting a new filling pressure in the head space 1a, if a pressure control system described in step 5 cannot regulate a new filling pressure within a parameterizable time.

1. 1. Ermittlung der Viskosität des Füllprodukts, beispielsweise im Produktzulauf 7 oder im Produkttank 1, über dazu geeignete Messgeräte, beispielsweise mittels einer Durchflussmesseinrichtung 8a mit der Möglichkeit der Viskositätsmessung, eines Inline- oder Prozess-Viskosimeters 8b, 8c oder mittels zumindest zweier Druckaufnehmer 8d, 8e zur Ermittlung des Druckabfalls im durchströmten Produktzulauf 7;
2. 2. Weitergabe der Viskositätsdaten, umfassend einen etwaigen Druckabfall, an die Steuereinrichtung 6;
3. 3. Ermittlung des viskositätsabhängigen Abfülldrucks, beispielsweise aus einer in der Steuereinrichtung 6 hinterlegten Viskositäts-Abfülldruck-Beziehung;
4. 4. Einstellen des Abfülldrucks an der Füllvorrichtung 10, d.h. des Gasdrucks im Kopfraum 1a des Produkttanks 1, mittels des Druckreglers 9 und des Druckaufnehmers 3;
5. 5. Wiederholung der Schritte 1 bis 4 bis Produktionsende;

Viscosity-dependent regulation of the filling pressure during regular production:

1. 1. Determination of the viscosity of the filling product, for example in the product inlet 7 or in the product tank 1, using suitable measuring devices, for example by means of a flow measuring device 8a with the possibility of viscosity measurement, an inline or process viscometer 8b, 8c or by means of at least two pressure sensors 8d, 8e for determining the pressure drop in the product feed 7 through which the flow passes;
2. 2. Forwarding of the viscosity data, including a possible pressure drop, to the control device 6;
3. 3. Determination of the viscosity-dependent filling pressure, for example from a viscosity-filling pressure relationship stored in the control device 6;
4. 4. Setting the filling pressure on the filling device 10, ie the gas pressure in the head space 1a of the product tank 1, by means of the pressure regulator 9 and the pressure sensor 3;
5. 5. Repeat steps 1 to 4 until the end of production;

Depending on the implementation of the control software and / or control hardware of the control device 6, deviations and / or additions to the processes set out above are possible.

Controlling the filling pressure through the viscosity of the filling product determined in the product path enables the efficiency of the filling device 1 to be increased. This is achieved on the one hand by eliminating filling tests at the start of production or when restarting after a production interruption. On the other hand, filling tests after strong or abrupt changes in the viscosity of the filling product, for example due to temperature fluctuations or due to different batch properties. Furthermore, when new, previously unknown filling products are put into operation, filling tests can be dispensed with due to the data collected (viscosities, densities, etc.), for example by comparing them with the current filling product data and the resulting optimal filling pressures in practice.

A filling pressure optimized in this way also contributes to a reduction or avoidance of overfilled and thus possibly contaminating containers, whereby machine stops, cleaning times and restart situations are minimized.

Product losses can be minimized by optimizing the filling pressure as described here. The materials required for filling tests - filling product, container and the like - usually have to be discarded for reasons of hygiene and quality. By eliminating filling tests, material loss can be minimized. Furthermore, the containers rejected due to overfilling or underfilling can be minimized. Ideally, the filled containers are salable from the first round of filling, which optimizes the performance of the filler.

Another technical contribution consists in improving the filling accuracy by means of always optimal flow rates set via the viscosity-dependent filling pressure control. Even slight fluctuations in viscosity with simultaneous impairment of the filling accuracy can be responded to quickly, almost immediately. The almost constant filling conditions result in a reduction in soiled containers.

As far as applicable, all of the individual features shown in the exemplary embodiments can be combined with one another and / or exchanged without departing from the scope of the invention.

Reference list

10

Device for filling containers with a filling product

1

Product tank

1a

Headspace of the product tank

2

Filling organ

3

Pressure transducer

4th

Level sensor

5

Temperature sensor

6th

Control device

7th

Product feed

8th

Viscosity determination device

8a

Flow meter

8b

Inline viscometer

8c

Process viscometer

8d

Pressure transducer

8e

Pressure transducer

9

Pressure regulator

Claims (15)

Device (10) for filling a container with a filling product, preferably a food, wherein the device (10) comprises: a product path (1, 2, 7) for transporting and introducing the filling product into the container; a viscosity determination device (8) for determining a viscosity of the filling product in the product path (1, 2, 7); a filling pressure setting device (1a, 9) for setting a filling pressure under which the filling product is introduced into the container; and a control device (6) which is communicatively coupled to the viscosity determination device (8) and the filling pressure setting device (1a, 9) and is configured to determine from the viscosity of the filling product determined by the viscosity determination device (8) using a viscosity-filling pressure relationship which a functional relationship between the viscosity and the filling pressure is to determine a target filling pressure and to control the filling pressure adjustment device (1a, 9) for adjusting the filling pressure to the target filling pressure. Device (10) according to Claim 1, characterized in that the product path (1, 2, 7) has a product inlet (7), a product tank (1) in fluid connection therewith and one or more filling elements (2) in fluid connection therewith , wherein the product inlet (7) is set up to guide the filling product into the product tank (1), and the filling members (2) are set up to feed the filling product located in the product tank (1) into containers. Device (10) according to Claim 2, characterized in that the product tank (1) has a head space (1a) above the filling product, which is filled with gas, preferably sterile air or an inert gas, and a pressure regulator (6) communicatively coupled to the control device (6). 9) is provided, which is set up to regulate the gas pressure in the head space (1a), whereby the filling pressure can be adjusted, wherein a pressure sensor (3) is preferably provided, which is communicatively coupled to the control device (6) and is set up to measure the gas pressure to measure in the head space (1a) of the product tank (1) and to transmit to the control device (6). Device (10) according to claim 2 or 3, characterized in that the viscosity determination device (8) a flow measuring device (8a) and / or an inline viscometer (8b) for determining the viscosity of the filling product in the product inlet (7) and / or a Process viscometer (8c) for determining the viscosity of the filling product in the product tank (1). Device (10) according to one of the preceding claims, characterized in that the viscosity determination device (8) has at least two pressure sensors (8d, 8e) which are set up to measure the pressure occurring during a flow of filling product at at least two different points in the product path detect, wherein the control device (6) is set up to use the pressure difference between the two pressure sensors (8d, 8e) as a measure for the viscosity of the filling product or to calculate such from the pressure difference. Device (10) according to one of the preceding claims, characterized in that the control device (6) is set up to set the target filling pressure at the start of production and / or after an interruption in production and / or in the event of a viscosity change exceeding a threshold value to determine the viscosity of the filling product determined by the viscosity determination device (8) using the viscosity-filling pressure relationship, and otherwise preferably to regulate the filling pressure by comparing a current or average flow rate with a target flow rate. Device (10) according to one of the preceding claims, characterized in that the viscosity-filling pressure relationship is determined empirically or experimentally, preferably a product-specific, empirically determined function or database that indicates a suitable or optimal filling pressure as a function of viscosity. A method for filling a container with a filling product, preferably a food, the method comprising: Transporting the filling product along a product path (1, 2, 7) and introducing the filling product into the container; Determining a viscosity of the filling product in the product path (1, 2, 7) by means of a viscosity determining device (8); Determining a target filling pressure from the viscosity of the filling product determined by the viscosity determining device (8) using a viscosity-filling pressure relationship which is a functional relationship between the viscosity and the filling pressure; and Setting the filling pressure under which the filling product is introduced into the container by controlling a filling pressure adjustment device (1a, 9), so that the filling pressure adapts to the target filling pressure. Method according to Claim 8, characterized in that the product path (1, 2, 7) has a product inlet (7), a product tank (1) in fluid connection therewith and one or more filling elements (2) in fluid connection therewith, the filling product is transported via the product inlet (7) into the product tank (1), from the product tank (1) to the filling elements (2) and the filling elements (2) introduce the filling product accordingly into containers, with
the product tank (1) has a head space (1a) above the filling product, which is filled with gas, preferably sterile air or an inert gas, and
the gas pressure in the head space (1a) is regulated via a pressure regulator (9), whereby the filling pressure is set, preferably taking into account the measured values of a pressure sensor (3) which measures the gas pressure in the head space (1a) of the product tank (1). Method according to claim 9, characterized in that the viscosity determination device (8) has a flow measurement device (8a) and / or an inline viscometer (8b) which determine the viscosity of the filling product in the product inlet (7), and / or the viscosity determination device (8) ) has a process viscometer (8c) which determines the viscosity of the filling product in the product tank (1). Method according to one of claims 8 to 10, characterized in that the viscosity determination device (8) has at least two pressure sensors (8d, 8e) which detect the pressure occurring during a flow of filling product at at least two different points in the product path, and the pressure difference between the two pressure sensors (8d, 8e) are used as a measure of the viscosity of the filling product or such is calculated from the pressure difference. Method according to one of claims 8 to 11, characterized in that the target filling pressure at the beginning of a production and / or after an interruption of production and / or in the case of a viscosity change exceeding a threshold value from the viscosity determined by the viscosity determination device (8) Filling product is determined using the viscosity-filling pressure relationship. Method according to Claim 12, characterized in that, in a regular filling operation, the filling pressure is controlled by an alternative regulation without taking into account the viscosity-filling pressure relationship is regulated, preferably by comparing a current or average flow rate with a target flow rate. Method according to Claim 13, characterized in that the viscosity of the filling product in regular filling operation is determined by the viscosity determination device (8) and the alternative regulation is corrected. Method according to one of Claims 8 to 14, characterized in that the viscosity-filling pressure relationship is determined empirically or experimentally, preferably a product-specific function or database is determined which indicates a suitable or optimal filling pressure as a function of the viscosity.

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