EP2861520B1 - Probe for filling head in filling machine - Google Patents

Description

The invention relates to a probe according to the preamble of claim 1 and in particular to a fill level determining the filling probe and a filling system or a filling machine for filling containers with a flowable or liquid filling material according to the preamble of claim 6.

For the purposes of the invention, "pressure filling" is generally to be understood as meaning a filling process in which the container to be filled in each case rests in a sealing position against the filling element and, as a rule, before the actual filling phase, i. is biased before opening the liquid valve via at least one controlled, formed in the filling gas path with a pressurized gas clamping gas (inert gas or CO2 gas), which is then displaced during filling of the inflowing the container contents increasingly as return gas from the container interior , also via at least one controlled gas path formed in the filling element. This biasing phase may be preceded by further treatment phases, for example, evacuation and / or flushing of the container interior with an inert gas, e.g. CO2 gas, etc., also via the gas paths formed in the filling element.

For the purposes of the invention, "non-pressurized filling" is generally to be understood as meaning a filling process in which the container to be filled is preferably in sealing position against the respective filling element with its container mouth and the container interior is controlled before the actual filling phase, ie before the liquid valve is opened , formed in the filling element gas paths is pretreated, for example, evacuated and / or purged with an inert gas such as CO2 gas, in which case the gas as the return gas, which is increasingly displaced during filling of the inflowing the container contents, at least one controlled, formed in Fülleiement gas path is discharged from the container interior.

"In sealing position with the filling element befindlicher container" means in the context of the invention that each container to be filled in the manner known to the expert with its container mouth tightly against the filling element or to a local there, the at least one discharge opening of the filling element surrounding gasket pressed ,

"Container" in the context of the invention, in particular cans and bottles made of metal, glass and / or plastic, but also other packaging, which are suitable for filling liquid or viscous products for pressure filling or for pressureless filling.

"Headspace" of the container is in the sense of that part of the container interior below the container opening, which is not occupied by the filling after filling.

The term "essentially" in the context of the invention means deviations from the exact value by +/- 10%, preferably by +/- 5%, and / or deviations in the form of changes that are insignificant for the function.

Filling or filling systems for filling containers with a flowable or liquid filling material, in particular in their training as rotating machines are known in numerous designs. In particular, it is also known to control the respective filling process or its filling phase, in which the contents controlled by at least one liquid valve in the container in question by controlling the filling height determining probes provided on filling elements of the filling machine when filling in the respective container extend the container opening. These probes are then, for example, electrical level probes with at least one probe contact, which then, when it dips into the filling level rising in the container filling, a closes the liquid valve causing or initiating delay probe signal supplies, so that the respective target level or Target filling level is reached in the container. A certain disadvantage of the electric level probes is that in case of failure of the respective probe contact and / or the probe signal processing electronics to overfilling of the container in question may occur, which is not desirable in practice.

As the filling height determining probes and return gas tubes are known, via which is arranged in the filling of the in-sealing position with the filling element arranged container, the displaced from the contents of the container interior Rürkgas is derived. After immersion of the respective return gas pipe in the liquid level rising in the container, the further inflow of the contents into the container interior upon reaching the desired level or desired Füllfüllmenge is terminated by the removal of the return gas is interrupted from the container via the return gas pipe. Return gas tubes as fill level determining probes have the advantage that at least Ideally at the end of the respective filling phase, the inflow of the contents into the interior of the container in question without the need for an electrical probe signal and without the risk of a possible failure of a probe contact and / or the probe signal processing electronics is terminated,

In all known filling systems with return gas pipe but closing the respective filling element or the liquid valve necessarily takes place only after a more or less long time interval and at a predetermined position or angular position of the movement of the circulating transport element, although the desired filling level or the desired filling amount longest is reached. This procedure has significant disadvantages. Thus, there is the danger that it comes in the time interval between the achievement of the desired level or the desired filling and the closing of the liquid valve by interference to overfilling of the relevant container, for example due to pressure fluctuations and / or sudden changes in the rotational speed of the transport element and / or by vibrations etc.

Furthermore, it is often unavoidable that the contents rise after immersion of the return gas pipe in the Follgutspiegel the contents still far in the return gas pipe or in the gas channel. As a result, it is then necessary to empty the return gas tube at the end of the actual filling phase into the relevant container in order to allow the contents to drip off after the filled container has been drained off Container to avoid the filling element. The time required for emptying the return gas tube affects, among other things, the performance of the filling machine or the filling system (filled containers per unit time). Furthermore, there is a risk that contaminations due to a contaminated container will be carried off into subsequently filled containers.

It is also known to determine the filling height determining probes, namely electrical Füllstandsandsanden or return gas pipes for adjusting the level or the level axially adjustable.

A probe with the features of the preamble of claim 1 and a filling machine with the features of the preamble of claim 6 are known ( US 4,586,548 A ), wherein the probe is formed by a gas pipe, which has probe contacts on a strip-like or lance-like section of the wall of the gas pipe. The gas pipe, which extends into a container when a container is arranged in a sealing position on the filling element, also serves as a return gas pipe for returning return gas, which is displaced from the container during filling by the inflowing product. The aim is to end the respective filling process with the probe contacts before the return gas tube dips into the mirror of the filling material rising in the container.

Filling elements are also known ( EP 0 658 511 A1 . WO 94/00377 A1 . EP 0 761 591 A1 . FR 2 592 869 A1 ), which in each case have, inter alia, a gas pipe extending into the respective sealing layer on the filling element and a rod-shaped probe element with at least one probe contact. The probe element extends through the gas pipe, specifically to form an annular gas channel surrounding the probe element in the gas pipe. The latter is used when filling the container as a return gas pipe for returning the displaced from the contents of the container rear gas. The disadvantage here but, inter alia, that only a greatly reduced flow cross-section remains through the probe element for the gas channel.

It is also known ( DE 42 37 044 A1 ), Return gas tubes also form as electrical level probe, ie on the inside of the tube or within the Gas channels of the return gas pipe to be provided with electrical probe contacts that generate an electrical probe signal after the response, ie after immersion return gas tube in the Füllgutspiegel and after the rise of the contents in the gas channel. The probe contacts or the electrical signals generated by these serve to indicate the respective level within a container.

It is also known ( DE 20 2013 676 ) To provide return gas pipes at its lower end or in the region of the local opening of its gas channel with lateral recesses or openings in order to influence the time course of the filling process at the end of the filling or the filling phase, and from the time at which the Fill in the container ascending Follgutsplegel has reached the bottom of the return gas pipe.

The object of the invention is to provide a filling level determining the filling probe for use in filling elements or filling machine, with which the disadvantages of known electrical level sensors and known return gas pipes are avoided with simplified construction and reduced production costs and which in particular a termination of the respective filling phase before Entry of contents into the gas channel of the return gas pipe or before the filling process and / or the performance of the filling machine impairing entry of the filling material into the gas channel allows, with high reliability. To solve this problem, a probe according to claim 1 is formed. A filling machine is the subject of patent claim 6.

The invention ideally combines the advantages of an electric fill level probe with the fundamental advantages of a return gas tube for filling level limitation, without the disadvantages of such a return gas tube necessarily having to be accepted, at least during trouble-free operation. At least during filling or during the filling phase, the containers are each in sealing position on the respective filling element.

Further developments, advantages and applications of the invention will become apparent from the following description of exemplary embodiments and from the figures. In this case, all described and / or illustrated features alone or in any combination are fundamentally the subject of the invention, regardless of their summary in the claims or their dependency. Also, the content of the claims is made an integral part of the description.

Fig. 1

in schematischer Darstellung und in Draufsicht eine Füllmaschine gemäß der Erfindung;

Fig. 2

in vereinfachter Darstellung und im Schnitt eines der Füllelemente der Füllmaschine der Figur 1, zusammen mit einem in Dichtlage am Füllelement angeordneten Behälter in Form einer Flasche;

Fig. 3 und 4

in vereinfachter Schnittdarstellung das untere Ende einer die Füllhöhe des Füllgutes in dem jeweiligen Behälter bestimmende Sonde im Schnitt sowie in Ansicht von unten;

Fig. 5

in einem Zeitdiagramm das Öffnen und Schließen des Flüssigkeitsventils der Füllelemente der Füllmaschine der Figur 1.

The invention will be explained in more detail below with reference to the figures of an embodiment. Show it:

Fig. 1

in schematic representation and in plan view of a filling machine according to the invention;

Fig. 2

in a simplified representation and in section one of the filling elements of the filling machine of FIG. 1 , together with a container arranged in sealing position on the filling element in the form of a bottle;

3 and 4

in a simplified sectional view of the lower end of the filling height of the filling material in the respective container determining probe in section and in view from below;

Fig. 5

in a time chart, the opening and closing of the liquid valve of the filling elements of the filling machine of FIG. 1 ,

In the figures, 1 is a filling machine of continuous design for filling containers 2 in the form of bottles with a flowable or liquid filling material. The filling machine 1 includes, inter alia, a transport element in the form of a rotor 3 driven in rotation around a vertical machine axis MA, on the circumference thereof in uniform angular intervals distributed around the machine axes MA and arranged in each case in the same radial distance from the machine axis MA a plurality of filling positions 4 is provided. Each filling position 4 comprises a filling element 5 and a container carrier 6, which is embodied in the illustrated embodiment by way of example as a bottle plate and with which the respective container 2 is pressed against the filling element 5 at least when filling in sealing position, in the region of an annular dispensing opening 7 (FIG. In a housing 9 of the filling element 5 are controlled by, for example pneumatically actuated control valves gas paths 10 and a liquid channel 11 is formed, which opens at the bottom of the filling element 5 at the discharge opening 7 and at its Top is connected via a product line 12 with a on the rotor 3 for all filling positions 4 jointly provided Füllgutkessel 13, which is filled during filling of the container 2 with the liquid contents, for example, with the filling material under a filling. Within the liquid channel 11, a liquid valve 14 is further provided, which is opened and controlled to fill the respective container at the beginning of the respective filling phase is closed when the level of contents in the container 2, the desired filling level or the target filling amount corresponding target level N1 has reached, that is, the respective container 2 is filled with the required Sollfüllhöhe or the corresponding desired filling quantity. In the illustrated embodiment, the liquid valve 14 includes a valve body 15 cooperating with a valve face in the liquid passage 11, which is moved up and down by an actuator 14.1 in a vertical filler axis FA oriented parallel to the machine axis MA to open and close the liquid valve 14.

The filling element 5 further comprises a filling height determining probe 16 from a coaxially arranged with the Füllelementachse FA return gas pipe 17, which forms a gas channel 18 and during filling with its lower end forming a probe end or with the local lower opening 18.1 of the gas channel 18 in the upper region (headspace) of the arranged at the filling position 4 container 2 extends. During the filling phase, the gas and / or vapor medium displaced from the inflowing contents from the container interior (for example, air or inert gas or CO 2 gas from a preceding rinsing and / or prestressing phase) via the gas channel 18 and the controlled gas paths 10, for example, in a gas space formed in the Füllgutspiegel Füllgutkessel 13 and / or in a rotor 3 for all filling positions 4 common annular channel 19 passed.

In conventional methods or filling systems for filling containers using return gas tubes as the filling height determining probes, the inflow of the filling material into the respective container is terminated when the lower end of the return gas pipe 17 is immersed sufficiently deep in the filling level in the container interior rising Füllgutspiegel, so that a further displacement of the return gas from the contents of the container 2 not occupied by the contents of the container 2 via the gas channel 18 is no longer possible and thereby the inflow of the filling material in the container 2 is inevitably terminated (return gas pipe / gas barrier principle). Only at a later time, i. At a predetermined angular position of the rotational movement of the rotor 3 then takes place, the closing of the liquid valve 14. As stated above, this known approach has considerable disadvantages. In order to avoid this, the probe 16 or its return gas pipe 17 is additionally designed as an electrical level probe with a probe contact 20, specifically outside the gas channel 18 at a lower open end 18.1 of the gas channel 18 in the direction of the Füllelementachse FA down ie in the direction of the container carrier 6 wegstehende lance or tab-like portion 21 of the return gas pipe 17th

In the illustrated embodiment, the portion 21 in the circumferential direction of the return gas pipe 17 has a width which is significantly smaller than the circumference of the return gas pipe 17 at its lower end. Furthermore, the portion 21 in the illustrated embodiment is partially formed by a lashing or lance-like continuation or by a lance-like or lance-like portion 22 of the wall of the return gas tube 17 made of an electrically conductive material, preferably made of a metallic material. This partial section 22 is produced, for example, by disengaging a tube piece forming the return gas tube 17 at its lower end. The probe contact 20, which is exposed at the lower, free end of the section 21 at the level N2 in the illustrated embodiment, is, for example, from the lower end of a conductor track 23 of a electrically conductive material formed outside of the probe contact 20 by insulating layers 24 opposite the return gas pipe 17 is electrically insulated and externally covered.

It is understood that the return gas tube 17 may be formed in the region of the probe contact 20 differently than described above, it is for example basically also possible that the over the lower, open end 18.1 projecting portion 21 exclusively of the conductor 23 and ggs. is formed by the insulating layers 24. However, all versions have in common that the probe contact 20 is located at the level N2 and thus in the direction of the filling element axis FA at a distance below the open end 18.1 of the return gas pipe 18.

The FIG. 5 shows in a time chart the opening and closing of the respective liquid valve 14 at the beginning or end of a filling phase. In the FIG. 5 is denoted by "1" the open and "0" the closed state of the liquid valve 14.

The operation of the filling machine 1 can be described, for example, as follows: The containers to be filled 2 are fed via an outer feed dog in the direction of arrow B and arrive via a container inlet 25 individually to a filling position 4. The filled container 2 to the filling positions taken from a container outlet 26 and fed according to the arrow C to a further treatment. On the angular range of the rotary movement of the rotor 3 between the container inlet 25 and the container outlet 26, for example, a pretreatment of the container 2 is carried out at least first by rinsing and / or biasing the interior of the respective in sealing position with a filling element 5 arranged container 2 with an inert gas, preferably with CO2 gas, and then in the actual filling phase, the filling of the container 2 with the contents. The filling phase is in each case at the time t1 ( Fig. 5 As soon as the filling material level of the filling material rising during filling in the container interior reaches the level N 2 and the probe contact 20 responds, which, for example, at the Angular position W2 or at time t2 (FIG. FIG. 5 ) is the case, a timer function is activated, which after a Time delay .DELTA.t at time t3, a closing of the liquid valve 14 causes ( Fig. 5 ). The time delay .DELTA.t is set so that the level of contents in the container 2 after closing the liquid valve 14 has the desired level N1. At least during filling or during the filling phase, the containers 2 are in sealing position on the respective filling element. 5

For example, while the angular position W1 at which the filling phase is initiated by opening the respective liquid valve 14 is fixed, the angular positions W2 and W3 are inter alia. depends on the rotational speed of the rotor 3. Regardless of the rotational speed of the rotor 3, the time delay .DELTA.t. This is determined, for example, from previous filling cycles and / or from tests and is stored, for example, as the type of filling material and the respective type and / or size of the container 2 typical process parameters in a filling machine 1 controlling computer 27 retrievable.

The inventive design of the filling machine 1 or its filling element 5 not only avoids the aforementioned disadvantages of the prior art, but also ensures an increased reliability in a simplified mechanical design and reduced manufacturing and / or assembly costs, as in a possible failure of at least one Probe contact 20 and / or the associated electronics in any case, the return gas pipe 17 acts as the filling level limiting element, ie after immersion of the return gas pipe 17 in the filling material level of the contents rising in the container interior further feed of contents is stopped in the container in question.

The return gas pipe 17 preferably also has other functions, for example, for a pretreatment of the container 2 in at least one of the actual filling phase preceding pretreatment phase. For example, the return gas tube 17 serves to rinse and / or bias the container interior with an inert gas, e.g. CO2 gas, etc.

In the illustrated embodiment of the invention, the return gas pipe 17 at the lower open end 18.1 in addition to at least one lateral recess 28th Mistake. This makes it possible to flush after completion of the filling phase, ie after closing the liquid valve 14 not occupied by the contents headspace of the respective filled container 2 with an inert gas, in spite of a short, based on the Füllelementachse FA axial length of the section 21st and despite the fact that the desired level N1 is slightly above the level of the open end 18.1.

The invention has been described above by means of an embodiment. It is understood that numerous changes and modifications are possible. Thus, it is possible, for example, to provide a plurality of probe contacts 20, again preferably so that at least one probe contact 20 is located at a distance below the open end 18.1 of the gas channel 18. In the case of at least two probe contacts 20, which are spaced apart at least in the direction of the filling element axis FA, then there is the possibility that, when the probe contact 20, which has the greater axial distance from the open end 18.1, responds, the relevant filling element 5 is in a state of "rapid filling is controlled in a state of "slow filling" and only when the response of the further probe contact 20, the timer function for the time-delayed closing of the liquid valve is activated.

Furthermore, it is also possible to initiate the closing of the liquid valve 14 without delay, or to switch the filling element 1 into a different operating state when the probe contact 20 responds, for example, from the state "fast filling" to the state "slow filling", wherein the inflow of the filling material into the arranged in sealing position on the filling element 1 container 2 by the return gas pipe 17 or by the immersion of the return gas pipe in the rising in the container 2 Füllgutspiegel. This switching from the operating state "fast filling" to the operating state "slow filling" means that in the operating state "slow filling" the filling material flows into the respective container 2 with a reduced filling speed (product quantity per unit time).

LIST OF REFERENCE NUMBERS

1

filling Machine

2

container

3

rotor

4

filling position

5

filler

6

container carrier

7

discharge opening

8th

centering bell

9

control valve

10

gas path

11

liquid channel

12

product line

13

Füllgutkessel

14

liquid valve

14.1

actuator

15

valve body

16

probe

17

Return gas pipe

18

gas channel

18.1

Lower open end of the gas channel

19

annular channel

20

probe contact

21

section

22

Part of the wall of the return gas pipe

23

conductor path

24

insulating

25

container inlet

26

container outlet

27

process computer

28

opening

A

Direction of rotation of the rotor 3

B, C

Transport direction of the container 2

M

machine axis

FA

filling element

N1, N2

Level of the product level

Claims (11)

1. Probe for use in filling elements of filling systems or filling machines (1) for filling containers (2) with a free-flowing or liquid filling material, wherein the probe (16), which during filling extends into the respective container (2) with one probe end and determines the filling level of the filling material in the container (2), is designed as a gas return pipe (17) with at least one gas channel (18), which is open at one end of the gas return pipe (17) at an opening (18), and additionally comprises at least one electrical probe contact (20), wherein the at least one electrical probe contact (20) is located in the axial direction of the gas return pipe (17) spaced at a distance in front of the opening (18.1) of the gas channel (18), and wherein the at least one probe contact (20) is provided at a section (21) of the wall of the gas return pipe, projecting over the end of the gas return pipe (17) in the form of a strip or lance,
   characterised in that
   the gas channel (18) at the end of the gas return pipe (17) is additionally open at at least one lateral cut-out aperture (28).
2. Probe according to claim 1, characterised in that the at least one probe contact (20) is located at the end of the strip or lance shaped section which is remote from the gas return pipe (17).
3. Probe according to claim 1 or 2, characterised in that the strip or lance shaped section (21) is formed partially from a part section (22), preferably from a part section (22) of the wall of the gas return pipe (17), produced by mortising out.
4. Probe according to any one of the preceding claims, characterised in that the at least one electrical probe contact (20) is located outside the gas channel (18).
5. Probe according to any one of the preceding claims, characterised by at least two probe contacts (20), which are spaced apart from one another at least in the axial direction of the gas return pipe (17), and of which at least one is located outside the gas channel (18) and spaced at distance in front of the opening (18.1) of the gas channel (18).
6. Filling machine for the filling of containers (2) with a free-flowing or liquid filling material, with at least one filling element (1), which comprises a probe (16), which during filling extends into the containers and which determines the filling level in the respective container (2), which is configured according to any one of the preceding claims, characterised in that
   the gas return pipe (17) forms a further element determining the filling height in the respective container (2).
7. Filling machine according to claim 6, characterised in that the at least one filling element (1), together with a container carrier (6), forms a filling position (4), and that the at least one probe contact (20) is offset in the direction towards the container carrier (6) in relation to the at least one opening (18.1) of the gas channel 18).
8. Filling machine according to claim 6 or 7, characterised by a control device (27), which, on actuation of the at least one probe contact (20), generates a signal which causes the closure of the at least one liquid valve (14) and/or the switching over of the operational state of the filling element (1).
9. Filling machine according to claim 8, characterised in that the control device (27), on the actuation of the at least one probe contact (20), activates a timer function for a time-delayed closure of the at least one liquid valve (14).
10. Filling machine according to claim 9, characterised in that in the control device (27) the time delay (Δt) is adjusted, and/or is stored as a typical process parameter for the type and/or size of the containers (2) and/or for the nature of the filling material, in such a way that, at the closure of the at least one liquid valve (14), the reference filling level (N1) is reached in the respective container.
11. Filling machine according to any one of the preceding claims, characterised in that the control device (27), on actuation of the at least one probe contact, causes a switchover of the filling element (1) from one state (rapid filling) into another state (slow filling).

Images