EP2460761B1 - Method and device for filling containers - Google Patents

Description

The present invention relates to a method for filling containers with liquids. Such devices and methods have been known for a long time from the prior art. Thus, for example, filling devices are known which have a multiplicity of filling elements, which are arranged, for example, on a filling wheel and which respectively fill the containers arranged thereon with liquid. In this case, methods for controlling the respective filling elements from the prior art are known. For example, it is known that the individual filling elements time-controlled make the dosage of the liquid products. Also, for example, a weight-dependent control depending on an already reached filling weight would be possible.

In filling processes, it is not possible to keep the influencing variables constant on the filling process. Fluctuations in the boiler level, product temperature fluctuations, working pressure drops and different filler speeds occur during the filling process.

From the WO 97/00224 For example, a method for filling containers with a pressurized fluid is known. In this case, the pressure of a liquid is measured and fed to a control device, which controls the fill valve by means of a drive signal from the measured pressure of the liquid and the desired filling quantity to be filled. Furthermore, the control device calculates the actually filled filling quantity from a totaling Partial volumes, which result in consideration of the respectively measured pressure of the liquid, the time intervals between the individual pressure measurements and a pressure / flow characteristics of the filling valve.

The GB 2 288 168 A describes a "master slave" fill valve system in which a "master fill valve and at least one" slave "fill valve are provided, arranged on a carousel, including a boiler and supply line the preamble of claim 1. The WO 2005/080202 A1 describes a filling machine with time-controlled metering valves. In this case, at least one guide valve is provided, which has a flow measuring device which is connected to a computer unit which calculates the time for the filling. On the basis of this flow measuring device or the data output from this, the other filling valves of the system are controlled.

In this approach, it has proven to be problematic that the individual filling valves often differ and therefore the known from the prior art control method does not consider such a deviation of the valves with each other.

The present invention is therefore based on the object to provide a method for time-controlled metering of liquid products, which also takes into account differences in the individual filling elements or valves. This is achieved according to the invention by a method according to claim 1. Advantageous embodiments and Welterbildungen are the subject of the dependent claims.

In a method according to the invention for filling containers with liquids, the containers are filled by means of a plurality of controllable filling elements and the liquid is supplied to these filling elements starting from a reservoir common to the filling elements for holding the liquid. During the filling process, the containers are transported at least in sections along a circular path and the filling of the containers is controlled by at least one filling element as a function of at least one first parameter characteristic of the liquid in the reservoir. This parameter is set during the filling process at predetermined time intervals repeatedly determined.

Furthermore, the filling of the containers by at least one second filling element is likewise controlled in dependence on the parameter characteristic of the liquid present in the reservoir, with at least one characteristic parameter being taken into account for the control of at least one filling element.

According to the characteristic of the filling element parameter is determined by filling containers with at least two different quantities. Overall, therefore, a time-filling method is preferably carried out.

It is therefore initially proposed that during the filling of the liquid products, an incremental query of the influencing variables of the filling process is carried out. However, since the individual filling elements are not completely identical to each other and also do not show a completely identical filling behavior, it is proposed according to the invention that this difference in the individual filling elements is also taken into account. In this way it is possible, but not mandatory, that a control valve is used for the control, but the other valves or their differences are also taken into account.

Advantageously, the reservoir for the liquid rotates with the individual filling elements.

In a further advantageous method, the filling element and preferably have all filling elements each controllable filling valves, which control the filling of the liquid into the containers.

In order to be able to react constantly to the influencing variables of the filling process, for example variables which depend on the liquid in the reservoir, it is advantageous to use a controller which calculates the course of the filling process incrementally and thus controls the filling time.

For controlling a multiplicity of filling elements, at least one parameter which is characteristic in each case for these filling elements is advantageously taken into account. Advantageously, at least one parameter characteristic of each of these filling elements is taken into account for controlling all filling elements. This respective characteristic parameter can be determined, for example, within the scope of a calibration operation for each individual filling element.

In a further advantageous method, the filling of the containers is controlled in dependence on a multiplicity of parameters characteristic of the liquid present in the reservoir. It is possible that the said parameters are recorded regularly.

In a further advantageous method, the parameter is selected from a group of parameters which include a temperature of the liquid in the reservoir, a geodetic level of the liquid in the reservoir, an angular frequency of a rotation of the reservoir, a level of the liquid in the reservoir , a density of the liquid in the reservoir, a pneumatic working pressure, combinations thereof and the like.

Advantageously, the pneumatic working pressure, the filler speed, the product temperature and the current boiler level are queried in each time increment and the filling quantity of this time interval is calculated therefrom. The individual quantities of the time increments are added up in the course of the filling and compared with the Abschaltfüllmenge. Advantageously, a shutdown signal is output when reaching the Abschaltfüllmenge and thus the relevant filling valve is closed.

In a further advantageous method, the parameter characteristic of the filling element is determined as a function of a flow rate of the liquid passing through this filling element. In particular, the said filling element is held in an open position and the flow passing through this opened valve is determined.

In a further advantageous method, a height of the level of the liquid in the reservoir is determined as a function of a distance to a geometric axis of rotation of the reservoir. It should be noted that the level, especially at faster revolutions, depending on this distance is not constant, but, for example, funnel-like formations can result, which cause closer to the axis of rotation of the level is lower and further out the level is higher ,

In a further advantageous method, at least one characteristic parameter is determined in a calibration operation of the system and stored in a memory device. In this case, for example, the respective filling quantities or the flow rates through the individual open filling valves can be measured and based on these filling quantities and / or flow rates actual deviations of the filling elements with each other or also with respect to a reference value can be determined.

Advantageously, the characteristic of the filling element parameter is determined by filling containers with at least two different quantities. The individual filling elements deviate from one another, in particular during the opening process of the valves and during the Schlleßvorgangs the valves, but also during the filling process at a constant flow rate. By calibrating with two different filling quantities, it is possible in this way to determine very precisely those differences which occur, in particular, during the opening and closing of the respective valve.

Furthermore, a device not claimed here for filling containers with liquids is described. This device has a rotatable about a predetermined axis of rotation carrier on which a plurality of controllable filling elements for filling the containers is arranged. Furthermore, the device has a reservoir for storing the liquid to be filled and for supplying the filling elements with the liquid. In this case, this reservoir is also rotatable about the predetermined axis of rotation and equipped with at least one first sensor device, which detects at least one characteristic for the liquid present in the reservoir first parameter.

Furthermore, a control device is provided, which controls the filling of the containers by the individual filling elements on the basis of the first parameter.

In this device, the filling curves are controlled independently by the individual filling elements and the control device takes into account for the control of at least one filling element additionally at least one characteristic of this second filling element or a filling process by means of this filling element parameters.

Therefore, it is also proposed on the device side that the differences in the individual filling elements or the special characteristics of the individual filling elements are taken into account in their control.

In a preferred embodiment, the device has a memory device in which characteristic parameters are stored for each individual filling element.

Further advantages and embodiments will become apparent from the accompanying drawings;

• Fig. 1 eine schematische Darstellung einer Vorrichtung zum Befüllen von Behältnissen;
• Fig. 2 eine Darstellung eines Füllverlauf für ein Füllelement; und
• Fig. 3 eine weitere Darstellung zur Aufteilung des Füllverlaufs.

Show:

• Fig. 1 a schematic representation of an apparatus for filling containers;
• Fig. 2 a representation of a filling curve for a filling element; and
• Fig. 3 another illustration of the distribution of the filling process.

Fig. 1 shows a schematic representation of a device 1 for filling containers. This device has a reservoir 4, in which a liquid 5 is arranged. This reservoir rotates here about an axis of rotation D. The reference numeral 8 roughly indicates a carrier, such as a filling wheel, on which a plurality of filling elements 2 are arranged, each of which serves to fill the containers 10. For this purpose, the filling elements 2 on filling valves, said filling valves here have filling cone 22, which along the double arrow P are movable. The reference numeral 24 denotes a support for the container and reference numeral 26 is a so-called CIP cap, which can be placed on the discharge opening 28 of the filling element 2 for cleaning the filling element. The reference numeral 36 refers to a return line for returning a cleaning medium. The carrier is also rotatably arranged about the rotation axis D, wherein it rotates in synchronism with the reservoir 4 at the same angular frequency.

The reference numeral 30 designates in its entirety a drive for the filling element 2, i. the drive that controls the filling of the containers 10. The reference numeral 34 denotes the product line leading from the reservoir 4 to the individual filling elements 2. By means of a diaphragm valve 16 filling speeds can be controlled, more precisely, the switch can be made to a second filling speed here. The reference numeral 32 denotes a throttle, which is arranged at the outlet of the reservoir 4.

The reference numeral 12 roughly indicates a sensor device which measures at least one characteristic property of the liquid 5 in the reservoir 4. As mentioned above, this may be, for example, a temperature or a level of this liquid. However, it is also possible to provide a plurality of sensor devices.

A control device 20 controls the filling of the containers 10 with the contents as a function of the measured parameter.

FIG. 2 shows a flow curve K, which illustrates the filling of the containers with a certain filling valve. The time in seconds is plotted on the ordinate and the flow Q in ml / s on the coordinate. It can be seen that in an initial section A first the flow rate Q increases sharply, then remains substantially constant over a certain period of time (section B) and finally returns to zero in a section C again. The black line K indicates the actual flow and the line K1 an approximation of the flow.

It can be seen that the filling process is divided into a plurality of time increments Z, during which the individual measurement parameters are measured.

An important component in the calculation of this flow curve K1 is the maximum flow rate Qmax. This is recalculated in each time increment Z and depends, for example, on the geodetic height z of the product to be filled (this geodetic height resulting from the base height of the reservoir plus the boiler level.) Another parameter for determining the flow velocity is the centrifugal acceleration a _z (at an angular frequency w) and the product temperature T. Taking these parameters into account, the flow rate Qmax is calculated according to the following formula: $$\begin{array}{l}{Q}_{\mathrm{Max}}=(\left(-{1\cdot 10}^{-5}<figure-callout\; id="2"\; label="\cdot \; \omega "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>\left(\frac{{\omega }^{}}{}\right)\left(\frac{{}^2}{2\cdot G}\cdot \left({r_i}^2-{{\mathrm{<figure-callout\; id="2"\; label="r\; s"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">r\; </figure-callout>}}_s}^2\right)+z_s\right)-\mathrm{8th}.4\cdot {10}^{-3}\right)<figure-callout\; id="2"\; label="\cdot \; T"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>T^{}{}^2+\left(-{4\cdot 10}^{-4}<figure-callout\; id="2"\; label="\cdot \; \omega "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>\left(\frac{{\omega }^{}}{}\right)\left(\frac{{}^2}{2\cdot G}\cdot \left(r_i^2-{\mathrm{<figure-callout\; id="2"\; label="r\; s"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">r\; </figure-callout>}}_s^{}\right)+z_s\right)1.3525\right)\cdot T+\\ (15.68\cdot {10}^{-2}<figure-callout\; id="2"\; label="\cdot \; \omega "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>\left(\frac{{\omega }^{}}{}\right)\left(\frac{{}^2}{2\cdot G}\cdot \left(r_i^2-{\mathrm{<figure-callout\; id="2"\; label="r\; s"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">r\; </figure-callout>}}_s^{}\right)+z_s\right)+70.01))+{\tilde{a}}_z\cdot \left(-5.6543\cdot {10}^{-3}<figure-callout\; id="2"\; label="\cdot \; \omega "\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">\cdot \; </figure-callout>\left(\frac{{\omega }^{}}{}\right)\left(\frac{{}^2}{2\cdot G}\cdot \left(r_i^2-{\mathrm{<figure-callout\; id="2"\; label="r\; s"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">r\; </figure-callout>}}_s^{}\right)+z_z\right)+10.979\right)\end{array}$$

However, the individual filling elements are mechanical components that bring different dead times and flow resistance because of their manufacturing tolerances. Therefore, a correction method for the other filling valves is proposed according to the invention.

Fig. 3 shows a diagram illustrating this method. The flow process is divided into five time intervals t1, t2, t3, t4 and t5. At the time t1 acts it is the dead time of the valve, which is dependent on the working pressure of the pneumatic valve control. The time period t2 indicates the rising range of the flow curve, which period depends on the level of the reservoir, its speed and the product temperature. The time period t3 denotes the constant filling area up to the switch-off time which can be calculated as a function of the filling quantity to be filled.

The periods t4 and t5 designate the follow-up time from the switch-off time, this follow-up time in turn being dependent on the level, the speed and the product temperature.

In the following, the calibration of the individual filling elements will be described in detail. When filling two different quantities only the length of time t3 changes. A filling with a first filling quantity, for example 500 ml, and a filling with a second filling quantity, for example 1000 ml, are used as a basis. The ratio of the calculated time intervals t3 to the fill amounts is, for example, as experimentally confirmed 1: 2.24. The nominal volume is first set to 500 ml on the device 1 and then to 1000 ml and then a filling process is carried out in each case. The actual quantities are weighed to determine the volume actually filled. The deviation from actual to nominal volume is designated for the 500 ml filling with ΔV ₅₀₀ and for the 1000 ml filling with ΔV ₁₀₀₀ . Subsequently, these values .DELTA.V ₅₀₀ and .DELTA.V _{1000 are} each divided into a deviation in the constant filling area X1 and a deviation in the rising area X2. The ratio of the running times of the constant filling area of a 1000 ml and a 500 ml filling is 2.24. This results in the following relationships for the two filling quantities:

For the filling quantity deviation with the 500 ml filling: $${\mathrm{.DELTA.V}}_{\mathrm{500}}={\mathrm{<figure-callout\; id="1"\; label="X"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">X</figure-callout>}}_{\mathrm{1}}+{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">X</figure-callout>}}_{\mathrm{2}}$$

For the filling quantity deviation with the 1000 ml filling: $${\mathrm{.DELTA.V}}_{\mathrm{1000}}=\mathrm{2}.\mathrm{24}\cdot {\mathrm{<figure-callout\; id="1"\; label="X"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">X</figure-callout>}}_{\mathrm{1}}+{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">X</figure-callout>}}_{\mathrm{2}}\mathrm{,}$$

$$X_1={\mathrm{\Delta V}}_{500}-\frac{2.24\cdot \mathrm{\Delta }{V}_{500}-V_{1000}}{1.24}$$

In this way, the following relationships arise for the deviations: $${\mathit{<figure-callout\; id="2"\; label="X"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">X</figure-callout>}}_2=\frac{2.24\times \Delta V_{500}-V_{1000}}{1.24}$$

$$X_1={\mathrm{.DELTA.V}}_{500}-\frac{2.24\cdot \mathrm{\Delta }{V}_{500}-V_{1000}}{1.24}$$

$$\mathrm{\Delta }{Q}_2=\frac{X_1}{t_3}$$

In this way, the exact deviations of the filling amount can be determined in the respective areas. For the determination of the flow corrections ΔQ1 and ΔQ2, the filling amount in the rising range is divided by the rising time and the filling amount in the constant filling range by the time span of this filling range: $$\mathrm{\Delta }{\mathrm{<figure-callout\; id="1"\; label="Q"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Q</figure-callout>}}_1=\frac{X_2}{{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">t</figure-callout>}}_2}$$

$$\mathrm{\Delta }{\mathrm{<figure-callout\; id="2"\; label="Q"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Q</figure-callout>}}_2=\frac{X_1}{{\mathrm{<figure-callout\; id="3"\; label="t"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">t</figure-callout>}}_3}$$

The parallel displacement of the flow path by ΔQ1 and ΔQ2 in the range of t2 and t3 is shown in Figure 3 represented by the lines V ₁ and V ₂ .

In this way it is altogether possible to determine correction factors or flow corrections ΔQ1 and ΔQ2, which are characteristic of the individual filling elements, on the basis of the actual filling quantities filled by the individual filling elements. For each individual valve, these corrections .DELTA.Q1 and .DELTA.Q2 can be stored in a memory device and taken into account in the actual working operation in each case for the respective filling elements.

It is recommended that at certain intervals, for example once a month, perform this calibration provided here again to determine in this way the respective flow corrections ΔQ1 and ΔQ2 for the individual filling elements.

LIST OF REFERENCE NUMBERS

1

contraption

2

infill

4

reservoir

5

liquid

8th

carrier

10

containers

12

sensor device

16

diaphragm valve

20

control device

22

filling cone

24

carrier

26

CIP cap

30

drive

32

throttle

34

product line

36

Return line

A

initial section

a _z

centrifugal acceleration

B

section

C

section

D

axis of rotation

K

Flow curve, actual flow

K1

Approximation of the flow

P

double arrow

Q

flow

Qmax

flow rate

T

product temperature

Z

time increment

t1

Dead time of the valve

t2

Rise region of the flow curve

t3

constant filling area

t4, t5

Follow-up time from the switch-off time

X1

constant filling area

X2

rising range

ΔQ1, ΔQ2

Flow Corrections

ω

angular frequency

Claims (7)

1. Method for filling containers (10) with liquids, wherein the containers (10) are filled by means of a plurality of controllable filling elements (2) and the liquid is fed to these filling elements (2) starting from a reservoir (4), common to the filling elements (2), for storing the liquid, wherein during the filling the containers (10) are transported at least in sections along a circular track and wherein the filling of the containers (10) by at least one filling element (2) is controlled as a function of at least one first parameter characteristic of the liquid in the reservoir (4) and this parameter is determined repeatedly at given intervals of time during the filling operation,
   wherein
   the filling of the containers by at least a second filling element is likewise controlled as a function of the parameter characteristic of the liquid in the reservoir (4), wherein for the control of at least one filling element (2) at least one parameter (ΔQ1, ΔQ2) characteristic of this filling element (2) is additionally taken into account,
   characterized in that
   the parameter (ΔQ1, ΔQ2) characteristic of this filling element is determined by filling of containers with at least two different filling amounts.
2. Method according to claim 1,
   characterized in that
   for the control of a plurality of filling elements (2), at least one parameter (ΔQ1, ΔQ2) in each case characteristic of these filling elements (2) is taken into account.
3. Method according to claim 1,
   characterized in that
   the filling of the containers (10) is controlled as a function of a plurality of parameters characteristic of the liquid in the reservoir (4).
4. Method according to at least one of the preceding claims,
   characterized in that
   the parameter is chosen from a group of parameters which contains a temperature of the liquid in the reservoir (4), a geodetic height of the liquid in the reservoir (4), a circular frequency of a rotation of the reservoir (4), a density of the liquid in the reservoir (4), a pneumatic working pressure or combinations of these.
5. Method according to at least one of the preceding claims,
   characterized in that
   the parameter (ΔQ1, ΔQ2) characteristic of the filling element (2) is determined as a function of a flow-through amount of the liquid passing through this filling element (2).
6. Method according to at least one of the preceding claims,
   characterized in that
   a height of the level of the liquid in the reservoir (4) is determined as a function of a distance from a geometric axis of rotation (D) of the reservoir (4).
7. Method according to at least one of the preceding claims,
   characterized in that
   at least one characteristic parameter (ΔQ1, ΔQ2) is determined in a calibration operation of the unit and is stored in a memory device.

Images