Method for filling cylindrical containers, in particular cans, and filling arrangement of a filling device and a container

Abstract

In a method for filling a predefined cylindrical container, a closed filling valve is moved with its filling tip through the container opening into the container. A gas contained in the container is displaced or compressed in the container. The container opening is sealed about the filling valve; the point in time of sealing determines a pressure in the container. The container is filled by opening the filling valve to allow fluid flow. The end face of the filling valve is below a fluid level in a radial gap volume between container wall and filling valve. Upward movement of the filling valve is adjusted according to predefined control parameters; filling occurs below fluid level in that the fluid level is above the end face of the filling valve. The filing valve is closed upon reaching the predefined filling volume. The closed filling valve is removed from the container.

Claims

1. A method for filling a container having a predefined cylindrical form with a fluid by using a filling device for the container, wherein the container comprises a concentric container opening comprising a diameter (d.sub.Do) which amounts to 70% to 99.5% of a container interior diameter (d.sub.Di), wherein the filling device comprises a filling valve, the filling valve comprising a piston controllably guided in a filling tube and comprising an open position in which the filling valve is in an open state and a closed position in which the filling valve is in a closed state, wherein the filling valve is movable relative to the container and comprises an outer diameter (d.sub.Fa) matching the diameter (d.sub.Do) of the concentric container opening so that a filling tip of the filling valve is insertable and retractable coaxially into/from the container through the concentric container opening with little play but without contact and without friction, wherein the filling tip of the filling valve comprises a volume (V.sub.F) occupying in the container a volume in a range of 49% to 99% of a container volume (V.sub.D) of the container; the method comprising the steps of: a) moving the filling valve, in the closed state, and the container relative to each other, wherein the filling tip of the filling valve is received through the concentric container opening in the container, and displacing a gas that is contained in the container in accordance with a volume (V.sub.F) of the filling tip of the filling valve out of the container or compressing in the container the gas that is contained in the container; a0) sealing the concentric container opening about the filling valve with a sealing element prior to step a) or during step a), wherein a point in time of sealing the concentric container opening determines a pressure (p) existing in the container after the filling valve has been completely inserted into an end position in the container; b) performing a filling process by moving the piston into the open position and allowing flow of the fluid into the container so that an end face of the filling valve, facing a container bottom and comprising a valve opening, is located below a fluid level in a radial gap volume (V) between a container wall of the container and the filling valve; c) adjusting during the filling process a relative upward movement of the filling valve within the container up to the concentric container opening according to a predefined control parameter, wherein the predefined control parameter takes into consideration a predefined filling volume in the container, wherein the filling process is carried out below fluid level in that the fluid level in the radial gap volume (V) during the relative upward movement is positioned above the end face of the filling valve during the filling process; d) closing the filing valve by moving the piston into the closed position when the predefined filling volume in the container is reached; and e) removing the filling valve in the closed state from the container.

2. The method according to claim 1, wherein, in an end position of the filling valve, the filling valve: is positioned at a predefined distance relative to the container bottom, or is positioned so that the end face of the filling valve contacts the container bottom directly or indirectly via a spacer.

3. The method according to claim 1, wherein the filling valve comprises a separation tube disposed about the filling tube, wherein the separation tube is controllably movable independent of the filling tube and of the piston; wherein: step a) includes: (a moving the filling valve to a position in the container such that a lower end of the separation tube of the filling valve is in an axial position with an axial gap (A) remaining between the lower end of the separation tube and the container bottom; step b) includes: (b0) allowing the fluid to flow through the axial gap (A) into the radial gap volume (V) between the container wall and the separation tube of the filling valve until a pressure compensation between a pre-adjusted filling pressure and a predefined container pressure is present, wherein a filling level (h) in the radial gap volume is determined by the pressure compensation; (b1) performing a relative upward movement of the filling tube within the separation tube, while the separation tube remains in the axial position relative to the container bottom and the piston remains in the open position of the filling valve, and filling the separation tube with the fluid; and (b2) at a predefined height (H) terminating the relative upward movement of the filling tube; step d) includes retracting the separation tube when the predefined height (H) is in a region of the concentric container opening and the container is completely filled.

4. The method according to claim 3, wherein an achievable filling level (h) achievable in the radial gap volume is smaller than a maximum filling level (h.sub.max) predefined by the container in the radial gap volume; the method further comprising: performing, after step (b2) and prior to step d), a relative downward movement of the filling tube, with the piston in the closed position, and forcing a fluid volume, present in the separation tube, through the axial gap (A) into the radial gap volume up to the predefined height (H); wherein step c) includes moving upwardly the filling tube, with the piston in the open position of the filling valve, within the separation tube up to the predefined height (H) which is located in a region of the concentric container opening and filling the separation tube with fluid; wherein step d) includes retracting the separation tube after step b2), wherein the fluid present in the separation tube remains in the container.

5. The method according to claim 4, comprising repeating the steps b0), b1), b2), and a.sub.1) until in step a.sub.1) the radial gap volume is filled completely up to the maximum filling level (h.sub.max).

6. The method according to claim 3, wherein, for filling the radial gap volume in step a1) with a single downward movement, the method further comprises, prior to performing the filling process according to step b), the step of determining a first predefined height (H.sub.1) as a function of the achievable filling level (h) in the radial gap volume that is achievable in step b0) with the pre-adjusted filling pressure and the predefined container pressure (p) so that a volume, which is limited in the separation tube (12) by the filling tube (11) at the first predefined height (H.sub.1), corresponds to a volume difference of the radial gap volume (V) between a maximum filling level (h.sub.max) and the achievable filling level (h).

7. The method according to claim 3, wherein the filling valve comprises an elastically expandable body, wherein: step a) includes completely inserting the filling valve together with the elastically expandable body through the concentric container opening into the container, expanding the elastically expandable body, and contacting an inner surface of the container with the elastically expandable body; step b) includes compressing the elastically expandable body by the fluid flowing into the container until the elastically expandable body contacts the separation tube of the filling valve and the radial gap volume between the container wall and the separation tube of the filling valve is filled.

8. The method according to claim 1, wherein the predefined control parameter is selected from the group consisting of a pre-adjusted filling time derived from a predefined filling volume in the container and an adjusted filling volume flow of the filling device, wherein closing of the filling valve in step d) is realized after the predefined filling time has lapsed; a predefined height (H) in a region of the concentric container opening (21) at which the upward movement of the filling valve or of the filling tube is terminated and the piston (10) is transferred into the closed position.

9. The method according to claim 1, wherein the step a0) includes arranging a volume compensation attachment, prior to the filling process of step b), between the concentric container opening and the sealing element, wherein a volume of an annular gap, formed between the volume compensation attachment and the filling valve, corresponds to a displaced volume that is caused by a portion of the filling valve present within the container when closing the filling valve in step d), wherein in the steps b) and c) a portion of the fluid flows into the annular gap and in step e) the portion of the fluid flows into the container so that the predefined filling volume is provided in the predefined container.

10. The method according to claim 9, wherein the filling valve comprises an elastically expandable body, wherein: step a) includes completely inserting the filling valve together with the elastically expandable body through the concentric container opening into the container, expanding the elastically expandable body, and contacting an inner surface of the container and of the volume compensation attachment with the elastically expandable body; step b) includes compressing the elastically expandable body by the fluid flowing into the container until the elastically expandable body contacts the filling valve and the radial gap volume between the container wall and the filling valve and an annular gap between the volume compensation attachment wall and the filling valve is filled, and upwardly moving the filling tube with the piston in the open position up to a predefined height (H) in a region of the concentric container opening.

11. The method according to claim 10, further comprising preventing the pressure in the container from surpassing a predefined highest pressure for the filling process by arranging a check valve or an overflow valve in the sealing element or in the volume compensation attachment.

12. The method according to claim 9, further comprising preventing the pressure in the container from surpassing a predefined highest pressure for the filling process by arranging a check valve or an overflow valve in the sealing element or in the volume compensation attachment.

13. The method according to claim 1, wherein the filling tube is a combined separation/filling tube and wherein the outer diameter (d.sub.Fa) of the filing valve corresponds to an outer diameter of the combined separation/filling tube, wherein the combined separation/filling tube is thin-walled and comprises an inner diameter (d.sub.Fi), wherein the combined separation/filling tube comprises a sealing seat for the piston, wherein the piston comprises an outer diameter (d.sub.K) matched to the inner diameter (d.sub.Fi) of the separation/filling tube, wherein the piston comprises a first open position, in which the piston is arranged proximal to the sealing seat, and comprises at least one second open position, in which the piston is arranged distal to the sealing seat, wherein the piston in the at least one second open position limits a displacement volume (V.sub.V) within the combined separation/filling tube (112), wherein the displacement volume together with the radial gap volume (V) results in the predefined filling volume of the container; wherein: step b) includes (b0) transferring the piston into the first open position and allowing flow of the fluid into a radial gap volume between the container wall and the separation/filling tube; (b1.1) upwardly moving the separation/filling tube with the piston in the first open position and allowing the fluid to flow farther into the radial gap volume until in the radial gap volume a pre-definable filling level is reached that depends on the pre-adjusted filling pressure and a pre-definable container pressure (p); (b2) at a second predefined height (H.sub.2), stopping the separation/filling tube and transferring the piston into the closed position, wherein the second predefined height (H.sub.2) is determined, prior to the filling process, as a function of the filling level in the radial gap volume (V) achievable in (b1.1) so that a volume that is limited below the separation/filling tube at the second predefined height (H.sub.2) corresponds to a volume difference of the radial gap volume (V) between the maximum filling level (h.sub.max) and the filling level (h) achievable in (b1.1), subsequently, completely inserting the separation/filling tube with the piston in the closed position into the container, subsequently, transferring the piston into the first open position and allowing flow of the fluid into the radial gap volume between the container wall and the separation/filling tube; wherein step c) includes transferring the separation/filling tube into a position in which an axial gap (A) between a lower end of the separation/filling tube and the container bottom remains, and transferring the piston into the at least one second open position, located in a region of the concentric container opening, and filling the separation/filling tube with the fluid, step d) includes retracting the separation/filling tube, when the at least one second open position is reached, until the piston is in the closed position and allowing the fluid to pass from the separation/filling tube into the container to completely fill the container.

14. The method according to claim 1, wherein the filling valve comprises an elastically expandable body, wherein: step a) includes completely inserting the filling valve together with the elastically expandable body through the concentric container opening into the container, expanding the elastically expandable body, and contacting an inner surface of the container with the elastically expandable body; step b) includes compressing the elastically expandable body by the fluid flowing into the container until the elastically expandable body contacts the filling valve and the radial gap volume between the container wall and the filling valve is filled, and upwardly moving the filling tube with the piston in the open position up to a predefined height (H) in a region of the concentric container opening.

15. The method according to claim 1, wherein in step a) the gas is displaced out of the container when the container opening about the filling valve is not sealed by the sealing element.

16. The method according to claim 1, wherein in step a) the gas is compressed in the container when the container opening about the filling valve is sealed by the sealing element.

17. A filling arrangement for performing the method according claim 1, wherein the filling arrangement comprises: a container having a predefined cylindrical form and comprising a concentric container opening comprising a diameter (d.sub.Do) that amounts to 70% to 99.5% of a container interior diameter (d.sub.Di) of the container; a filling device comprising a filling valve, the filling valve comprising a filling tube and a piston controllably guided in the filling tube; a sealing element arranged about the filling valve at the concentric container opening; the filling valve comprising an outer diameter (d.sub.Fa) matching the diameter (d.sub.Do) of the concentric container opening so that a filling tip of the filling valve is insertable and retractable coaxially into/from the container through the concentric container opening nearly without play but without contact and without friction; wherein the filling device is configured to provide a relative movement between the filling valve and the container to coaxially insert the filling tip of the filling valve into the container through the concentric container opening; wherein the filling tip of the filling valve comprises a volume (V.sub.F) that occupies in the container a volume in a range of 49% to 99% of a container volume (V.sub.D) of the container; wherein the filling device comprises a control action without a return air tube.

18. The filling arrangement according to claim 17, wherein the control action is configured to control the filling arrangement as a function of a predefined filling time at which the upward movement of the filling tube is terminated and the piston is moved into the closed position.

19. The filling arrangement according to claim 17, wherein the control action is configured to control the filling arrangement as a function of a predefined height (H) at which the upward movement of the filling tube is terminated and the piston is moved into the closed position.

20. The filling arrangement according to claim 17, wherein the control action requires no measuring means.

21. The filling arrangement according to claim 17, wherein the filling valve comprises a separation tube arranged about the filling tube, wherein the separation tube is controllably movable independent of the filling tube and of the piston.

22. The filling arrangement according to claim 17, wherein the filling tube is a combined separation/filling tube comprising an outer diameter (d.sub.Fa) matching the diameter (d.sub.Do) of the concentric container opening, wherein the combined separation/filling tube comprises a sealing seat, wherein the combined separation/filling tube is thin-walled and comprises an inner diameter (d.sub.Fi), and wherein the controllably guided piston is embodied as piston comprising a diameter (d.sub.K) matched to the inner diameter (d.sub.Fi) of the combined separation/filling tube, wherein the piston comprises a first open position in which the piston is arranged proximal to the sealing seat and further comprises at least one second open position in which the piston is arranged distal to the sealing seat.

23. The filling arrangement according to claim 17, further comprising a volume compensation attachment arranged about the filling valve between the sealing element and the concentric container opening.

24. The filling arrangement according to claim 23, wherein the sealing element or the volume compensation attachment comprises a valve.

25. The filling arrangement according to claim 24, wherein the valve is a check valve or an overflow valve.

26. The filling arrangement according to claim 17, wherein the filling valve comprises an end facing a container bottom of the container and provided with radial flow channels or spacers.

27. The filing arrangement according to claim 26, wherein the spacers are elastic or springy spacers or a unilaterally acting annular seal.

28. The filling arrangement according to claim 26, wherein the end of the filling valve is embodied by an end face of the filling tube or by an end face of a separation tube arranged about the filling tube.

29. The filling arrangement according to claim 26, wherein the filling tube is a combined separation/filling tube and wherein the end of the filling valve is embodied by an end face of the combined separation/filling tube.

30. The filling arrangement according to claim 17, wherein the filling valve comprises an elastically expandable body arranged along the filling tip at least at one section or about a section of the filling tube.

31. The filling arrangement according to claim 17, wherein the filling valve comprises a centering section arranged at the filling tip and tapering toward an end face of the filling valve facing a container bottom of the container.

32. The filling arrangement according to claim 17, wherein the filling tube and the piston each comprise an exchangeable filling tip section.

33. The filling arrangement according to claim 17, wherein the filling tube or the piston comprises at least one gliding radial spacer device configured to center the piston in the filling tube.

34. The filling arrangement according to claim 17, wherein the filling valve comprises a separation tube arranged about the filling tube and further comprises an elastically expandable body arranged along the filling tip at least at one section or about a section of the separation tube.

35. The filling arrangement according to claim 17, wherein the filling valve comprises a flow guiding structure arranged at an inner side of the filling tube; at an outer side of the piston; or at the inner side of the filling tube and at the outer side of the piston, wherein the flow guiding structure is disposed above sealing surfaces of the filling valve at an end of the filling valve facing a container bottom of the container.

36. The filling arrangement according to claim 35, wherein the flow guiding structure is formed by a coil web.

37. The filling arrangement according to claim 35, wherein the flow guiding structure is formed by an annular arrangement of guide vanes that are curved at least in one plane.

38. The filling arrangement according to claim 35, wherein the flow guiding structure is an annular arrangement of curved or uncurved moving vanes arranged at the rotatably arranged piston.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further embodiments as well as some of the advantages that are correlated with these and further embodiments will be more clearly and better comprehensible by means of the following detailed description with reference to the accompanying drawings. Objects or parts thereof which are substantially identical or similar may be provided with the same reference characters. The Figures are only a schematic illustration of an embodiment of the invention. It is shown in this context in:

(2) FIG. 1 sectioned side views of a filling arrangement according to the invention with a filling valve of filling tube and piston according to steps a) to e) of an embodiment of the method according to the invention;

(3) FIG. 2 sectioned side views of an alternative filling arrangement with a filling device that in addition comprises a separation tube, according to the steps a), b1), and b2) of an alternative embodiment of the method according to the invention;

(4) FIG. 3 a sectioned side view of a further embodiment of the filling arrangement of FIG. 2 in which the filling opening at the filling valve is sealed during a step a0) of an alternative embodiment of the method according to the invention;

(5) FIG. 4 a sectioned side view of a further embodiment of the filling arrangement of FIG. 2 in which a volume compensation attachment between sealing element and filling opening is arranged during a step b2) of an alternative embodiment of the method according to the invention;

(6) FIG. 5 sectioned side views of the filling arrangement of FIG. 3 in accordance with the steps b2), a1), and b1) as a continuation of the embodiment of the method according to the invention according to FIG. 2;

(7) FIG. 6 sectioned side views of a further filling arrangement according to the invention with a filling valve of the thin-walled combined separation/filling tube and a wider piston with greater stroke travel and two opened positions according to the steps a) to d1) of an alternative embodiment of the method according to the invention;

(8) FIG. 7 sectioned side views of a further filling arrangement according to the invention in accordance with FIG. 4, in addition with an elastically expandable body surrounding the separation tube, according to the steps a) to d1) and d2) of a further alternative embodiment of the method according to the invention;

(9) FIG. 8 schematic sectioned side views of a filling arrangement corresponding to FIG. 1 according to the steps 0) to e) of an embodiment of the method according to the invention with the course of the filling level;

(10) FIG. 9 schematic sectioned side views of a filling arrangement according to FIG. 2 and FIG. 5 according to the steps 0) to e) of an alternative embodiment of the method according to the invention with the course of the filling level;

(11) FIG. 10 a sectioned side view of a further embodiment of the filling arrangement with a valve in the sealing element and a unilaterally acting annular seal at the end face of the filling valve in order to avoid return flow out of the annular gap during counter pressure filling;

(12) FIG. 11 schematic sectioned side views of a filling arrangement according to FIG. 1, as in FIG. 8, with a filling valve with a conically tapering centering section at the filling tip;

(13) FIG. 12 a sectioned side view of a further embodiment of the filling arrangement with a filling valve with exchangeable filling tip and concentric spacer;

(14) FIG. 13 a schematic longitudinal section view of a filling valve according to the invention with a coil web-type flow guiding structure in the filling tube;

(15) FIG. 14 a schematic longitudinal section view of a filling valve according to the invention with a coil web-type flow guiding structure at the piston;

(16) FIG. 15 a schematic cross-section view of a filling valve according to the invention with a flow guiding structure of guide vanes at the piston;

(17) FIG. 16 a schematic cross-sectional view of a filling valve according to the invention with a flow guiding structure of moving vanes at the rotating piston.

DESCRIPTION OF PREFERRED EMBODIMENTS

(18) The invention concerns filling of cylindrical containersfor example, cansby means of a special filling arrangement. In this context, advantage is taken of the fact that cans, which in addition to bottles and cartons are the most important packaging for beverages, primarily for carbon dioxide-containing beverages such as beer or soft drinks, have an extremely precisely produced cylindrical shape with a coaxial filling opening that is only minimally smaller than the container diameter. The most commonly used can volumes in Europe are 0.33 l and 0.5 l, but there are also cans with a volume of 0.15 l, 0.2 l, and 0.25 l, as well as 1 l and 5 l. According to the invention, however, also containers with other volumes can be filled as long as the container volume is known.

(19) In the Figures, respective sequences of the filling arrangement in different method steps are illustrated; reference characters are therefore not provided in each illustration of the filling arrangement. The correlation with the components and objects without label is however easily apparent due to the equivalence of the illustrations.

(20) FIG. 1 shows a simplest embodiment of the method and of a filling arrangement suitable therefor which is comprised of the filling valve 1 and the container 2. In this context, a can is provided here whose substantially cylindrical shape at the upper end tapers slightly toward the coaxial filling opening 21. The taper serves primarily for receiving the cover, not illustrated here, which after completion of the filling process is attached and connected by (multiple) crimping with the rim of the can. The method according to the invention uses this difference between container (interior) diameter d.sub.Di, and the diameter d.sub.Do of the container opening 21.

(21) The diameter d.sub.Do of the container opening 21, as shown in the illustrated example of FIG. 1, can amount to between 70 and 99.5%, usually between 80 to 90% of the container interior diameter d.sub.Di.

(22) The movable filling valve 1 that is comprised in the simplest embodiment of filling tube 11 and controllably guided piston 10 comprises an outer diameter d.sub.Fa that is matched to the diameter d.sub.Do of the container opening 21 in such a way that the filling valve 1 can be inserted without contact and without friction but also, as much as possible, without play through the container opening 21 into the container 2. The method, that is also illustrated schematically simplified in FIG. 8, provides that the container 2 (in step 0) is arranged in relation to the filling valve 1 such that a coaxial centric insertion of the filling valve 1 through the container opening 21 into the container 2 is enabledthis can be realized by axial movement of the filling valve or of the container, for example, by means of a corresponding movable container receptacle (not illustrated). Prior to insertion, the container volume V.sub.D is filled with ambient air (optionally also another gas) at an initial pressure p.sub.0 (e.g. ambient pressure).

(23) In step a0) in FIG. 8, it is indicated by the block arrow that the filling valve 1 is inserted into the container 2 so that the pressure p in the container rises when the container opening 21 is sealed. However, also without sealing action, a (temporary) pressure increase may occur when the air can escape only slowly through the filling opening 21 about the filling valve 1.

(24) Step a) in FIG. 1 and FIG. 8 shows the filling valve 1 that has been completely inserted into the container 2. The filling tip of the filling valve 1 with the volume V.sub.F which has penetrated into the container 2 causes in this context either a pressure increase in the remaining gap volume V when the filling opening 21 is sealed or a displacement of a major portion of the gas volume out of the container so that the quantity of gas or air and thus oxygen that is present in the gap volume V (difference between container volume V.sub.D and inserted filling valve volume V.sub.F) is significantly reduced.

(25) As can be seen moreover in FIG. 1, the container 2 has a shaped bottom 22. So that the filling valve 1 can be completely inserted without deforming the bottom 22, the filling tube 11 at the end face end that comprises the sealing seat 13 for the piston 10 is shaped in accordance with the shape of the bottom 22.

(26) In method step b), the valve 1 is moved by transfer of the piston 10 into an open position so that fluid can flow into the container 2 while at the same time the open filling valve 1 is moved upwardly. In FIG. 8, the step b) is shown in two illustrations b.1) and b.2) wherein in the illustration b.1), by means of the block arrow, the opening action of the filling valve 1 is illustrated that is lifted only slightly away from the container bottomor comprises channels in the end faceso that fluid can flow into the gap volume V. In the second illustration b.2) of step b), the block arrow indicates the upward movement of the open filling valve 1 wherein the rate of upward movement is matched to the inflow rate of the fluid so that the end face of the valve 1 with the valve opening is always below the liquid level in the gap volume V.

(27) It is apparent that the contact surface of the fluid in the gap volume V is only a circular ring with ring width s (difference of half the container interior diameter d.sub.Di and of half the filling valve outer diameter d.sub.Fa). Due to this filling below fluid level in which the fluid level in the gap volume V is above the end face of the filling valve 1, the fluid contacts only at the circular ring-shaped contact surface the gas which is present in the container 2. The circular ring of the ring width s constitutes an extremely small contact surface so that the absorption of gas (in particular air oxygen) into the fluid is very minimal. The filling process below liquid level is continued by the upward movement of the filling tube 11 with the piston 10 in open position whereby hardly any turbulences are produced and the gas introduction through the contact surface is further reduced in this way. The reduced contact surface, together with the reduced air volume and the filling process below liquid level, leads to a significant reduction of oxygen absorption in the fluid.

(28) Step c), illustrated in FIG. 1, shows the open filling valve 1 at a level of the container opening 21 up to which the upward movement of the filling valve 1 within the container 2 is coordinated in regard to the filling process or the filling quantity or the filling rate. For this purpose, a predefined control parameter is employed that takes into consideration the predefined filling volume in the container 2. Since cans are very exactly manufactured in regard to their volume, the predefined filling volume corresponds to the nominal volume. In the method illustrated in FIGS. 1 and 8, the control parameter in step c) can be a predefined filling time which is derived from a predefined filling volume in the container 2 and an adjusted filling volume flow of the filling device. Advantageously, no complex sensor means are thus required in this context.

(29) After the predefined filling time, during which the upward movement of the open filling valve 1 with the inflow process below liquid level takes place, or upon reaching the predefined height H in the region of the container opening 21, closing of the filling valve 1 in a step d) takes place, as is indicated by the block arrow in the corresponding illustration in FIG. 8, wherein the predefined filling volume in the container 2 has been reached. Finally, in step e) the closed filling valve 1 is retracted so that the next container 2 can be subjected to the filling process.

(30) FIG. 11 shows a filling valve 1 with a conically tapering centering section 19 at the filling tip by which the coaxial centered introduction of the filling valve 1 through the container opening 21 into the container 2 is assisted.

(31) FIGS. 2 to 5 and FIGS. 9, 10 show method steps with a preferred filling arrangement in which the filling valve 1 in addition comprises a separation tube 12 that is directly and coaxially arranged about the filling tube 11 and can be controllably moved independent thereof. FIG. 2 shows the filling arrangement without seal, and in FIG. 5 with seal. The respectively illustrated method steps are however applicable to both variants.

(32) Identified method steps which corresponds to the method disclosed in FIGS. 1 and 9 will optionally not be described again. The method that is performed with the filling device with separation tube 12 is also characterized by the reduced contact surface, a reduced air volume, and the filling process below liquid level which lead to a significantly reduced oxygen absorption in the fluid.

(33) Accordingly, here also the filling valve 1 is completely inserted in step a) through the container opening 21 into the container 2. However, between the lower end of the separation tube 12 and the container bottom 22 an axial gap A remains in this context in order to allow fluid to flow into the gap volume V that is formed between the container wall 20 and the separation tube 12 when, as shown in FIG. 9 in step b0) by means of the block arrow in the piston, the piston 10 has been transferred into an open position of the filling valve 1.

(34) The filling method that utilizes a filling valve 1 with separation tube 12, as shown in FIG. 2, can be performed without sealing the container opening 21 so that gas or air can escape.

(35) However, in particular in the variant with the separation tube 12 a counter pressure filling process can be performed also in which the container opening 21 is sealed about the filling valve 1, as illustrated in FIGS. 3, 4, 5, and 10.

(36) In step b0), the piston 10 is transferred into an open position of the filling valve 1 and the fluid is allowed to flow through the axial gap A into the radial gap volume V between the container wall 20 and the separation tube 12. The fluid flows into the radial gap volume V until a pressure compensation between the filling pressure pre-adjusted in the filling device and the container pressure p exists, whereby the filling level h in the radial gap volume V is determined. The container pressure p can be predefined and depends on whether the container opening is sealed or not and whether a check valve or overflow valve is present.

(37) Thus, the fluid level does not rise any farther in the gap volume V in the container 2 with open filling valve 1 when a pressure compensation between pressure in the container 2 and filling pressure is reached.

(38) In order to now fill the gap volume completely up to the filling level h.sub.max, preferably a pumping step is performed (as needed, also several of the pumping steps described in the following can be performed).

(39) Upon the now following upward movement of the filling tube 11 with the piston 10 in open position within the separation tube 12, as indicated in step b1) by the block arrow above the piston, the separation tube 12 remains in its completely inserted position so that the separation tube 12 fills with fluid.

(40) In FIG. 2 and FIG. 9, it is moreover illustrated that in step b2) the upward movement of the filling tube 11 with the piston 10 in the open position is terminated at a predefined height H.sub.1 and the piston 10 is transferred into closed position. This height H.sub.1 is predefined as a function of the filling level h in the radial gap volume V which is achieved by the pre-adjusted filling pressure and the predefined container pressure p in step b0): The height H.sub.1 can be calculated based on the volume which is limited in the separation tube 12 by the filling tube 11 at the height H.sub.1 and that is to correspond to the volume difference of the gap volume V between the maximum filling level h.sub.max and the achievable filling level h.

(41) The fluid volume that is existing after step b2) up to the predefined height H.sub.1 in the separation tube 12 is pushed in step a1) (FIGS. 5 and 9), by complete insertion of the filling tube 11 with the piston 10 in closed position, out of the separation tube 12 through the axial gap A into the radial gap volume V. The fluid level therein rises correspondinglypreferably up to the maximum filling level, wherein the residual gas that is present is completely displaced out of the container. When the complete filling of the gap volume V cannot be achieved with one pumping step, optionally the step sequence b0)-b1)-b2)-a1)-b0) . . . must be repeated until in a step a1) the gap volume V is filled completely up to a region of the container opening 21.

(42) In the step c1) illustrated in FIG. 9, the filling tube 11 with the piston in open position is then moved upwardly within the separation tube 12 up to a region of the container opening 21, and the entire separation tube volume fills with fluid. The upward movement(s) of the filling valve 1 within the container 2 up to the container opening 21 is realized here also by time control because all volumes (filling volume, gap volume, volume difference, volume in the separation tube etc.) are predefined or can be predefined. After c1), the piston 10 is transferred into closed position and the separation tube 12 is retracted in step d1), when the filling tube 11 has reached the predefined height H in the region of the container opening 21, wherein the fluid column existing previously in the separation tube 12 up to the valve remains in the container 2 which is thus completely filled, so that the filling valve 1 is retracted in step e).

(43) For performing a counter pressure filling process with post pressurization enabled by the separation tube 12, the container 2 is sealed at the filling valve 1, as illustrated in FIG. 3 or 4. FIG. 3 shows a method step a0) during insertion of the filling valve 1 into the container 2 at a point in time at which the seal 14 is attached. By means of the point in time of attaching the seal 14 or the penetration depth of the filling valve 1 into the container 2 at this point in time, the pressure p is determined which is present in the sealed container 2 when the filling valve 1 according to step a) is completely inserted.

(44) As a function of the desired pressure p, the seal 14 can also be placed onto the container 2 prior to insertion of the filling valve 1, wherein a maximum pressure is achieved, based on the container volume V.sub.D and the volume V.sub.F of the completely inserted section of the filling valve 1, after the complete insertion of the filling valve 1 through compression of the gas quantity present in the container volume V.sub.D. For counter pressure filling, in order to prevent foaming of carbon dioxide-containing fluids during filling, a pressurization pressure of 3 bar can be adjusted in the container 2, for example, when a filling pressure of 2 bar is provided.

(45) In particular in such a case it is particularly advantageous when, as indicated in FIG. 10, at the end face of the separation tube 12 in the axial gap A a circumferentially extending unilaterally acting annular seal 18 such as, for example, a sealing lip is employed that prevents that fluid or gas can flow out of the gap volume V back into the separation tube 12. Escape of fluid through the axial gap A is permitted and can in particular be realized through one or several of the afore described pumping steps.

(46) FIG. 4 shows the additional arrangement of a volume compensation attachment 15 which is employed between the container opening 21 and the sealing element 14 in a sealing fashion when sealing the container opening 21 about the filling valve 1. The volume compensation attachment 15 is used preferably in an embodiment of the method that comprises in addition an elastically expandable body and that will be explained later on in connection with FIG. 7 in more detail.

(47) In order not to surpass a predefined highest pressure for the respective filling process in the container 2, a pressure relief valve 16 can be arranged in the sealing element 14 (see FIGS. 5 and 6) or in the volume compensation attachment 15 (see FIG. 7) and, as illustrated, can open, but must not open, into a gas discharge line 16.

(48) With the pressure relief valve 16 upon post pressurization in step a1), wherein the fluid volume that is present after step b2) up to the predefined height H.sub.1 in the separation tube 12 is pushed by complete insertion of the filling tube 11 with the piston 10 in closed position out of the separation tube 12 through the axial gap A into the radial gap volume V, it is prevented that the pressure p in the container 2 surpasses the predefined highest pressure. In addition, by keeping constant the pressure in the container 2, an increased gas introduction is avoided which otherwise would take place with increasing pressure.

(49) FIG. 6 shows in eight illustrations an embodiment of the method that employs an alternative filling valve 1 with a combined separation/filling tube 112. The difference to the filling valve 1 of FIG. 1 resides in that the separation/filling tube 112 with identical outer diameter d.sub.Fa, which is embodied to match the diameter d.sub.Do of the container opening 21, has a greater inner diameter d.sub.Fi and therefore has a significantly thinner wall than the filling tube 11 of FIG. 1. Therefore, the corresponding controllably guided piston 100 has a corresponding greater diameter d.sub.K which is matched to the inner diameter d.sub.Fi of the separation/filling tube 112. A further difference to the filling valve 1 of FIG. 1 resides in a significantly enlarged stroke travel of the piston 100 in the separation/filling tube 112: In addition to the (first) open position in which the piston 100, like the one in FIG. 1, is arranged proximal to, i.e., near a sealing seat 13 of the separation/filling tube 112, the thick piston 100 in the separation/filling tube 112 can be moved into a second open position in which the piston 100 is arranged distal to, i.e., remote, relative to the sealing seat 13 of the separation/filling tube 112. In this second open position, the piston 100 delimits a displacement volume V.sub.V within the separation/filling tube 112 that provides together with the gap volume V the predefined filling volume of the container 2.

(50) In the method variant illustrated in FIG. 6, in step a) the filling valve 1 is completely inserted into the container 2 until the end face of the filling valve 1 contacts the container bottom 22. The illustrated variant shows counter pressure filling wherein the container opening 21 is sealed about the filling valve 1. The adjustment of the pressure is realized as described above. The method can be performed however also without sealing action.

(51) The counter pressure filling method performable with this filling arrangement with the separation/filling tube 112 combines the method steps of the above-described method wherein in step b0) the filling valve 1 is opened in that the piston 100 is moved into the first open position of the filling valve 1 so that fluid can flow into the radial gap volume V between the container wall 20 and the separation/filling tube 112. Subsequently, an upward movement of the separation/filling tube 112 with the piston 100 in open position is performed in the step b1.1), wherein here also a filling process below fluid level is achieved in that the fluid level (not illustrated) in the gap volume V during the filling process during the upward movement is located above the end face of the filling valve 1. The additional advantages of the above examples are also realized with this embodiment.

(52) Thus, in step b2) at a predefined height H.sub.1 the upward movement of the separation/filling tube 112 with the piston 100 in the first open position is stopped and the piston 100 transferred into the closed position. Even without separate separation tube 12, by renewed complete insertion of the separation/filling tube 112 with the piston 100 in closed position in the step a1), a post pressurization or pumping step can be performed with which the level of the fluid level in the gap volume V can be raised, wherein the pressure in the container 2 due to the pressure relief valve 16 remains constant. Then, step b0) is repeatedwhether steps b1.1), b2), and a1) are repeated depends on the geometric conditions and the predefined height H.sub.1before in step c1) the separation/filling tube 112 is transferred into a position in which an axial gap A, as for the separation tube 12, remains between the lower end of the separation/filling tube 112 and the container bottom 22 before the piston 100 is moved into its second open position and the separation/filling tube 112 is filled with fluid. The position of the piston 100 in the second open position is selected such that the displacement volume V.sub.V within the separation/filling tube 112 supplements the gap volume V to the predefined filling volume so that in step d1) the separation/filling tube 112 is retracted to the predefined height H in the region of the container opening 21 until the piston 100 reaches the closed position so that the fluid passes from the separation/filling tube 112 into the container 2 and the latter is completely filled. The step e), not illustrated, follows in which the filling valve 1 is retracted. This method also uses the known geometric parameters and can be performed with time control with a coordinated movement sequence.

(53) A further advantageous embodiment of the method according to the invention with a filling arrangement that is also in accordance with the invention is illustrated in FIG. 7. Here, a filling valve 1 with separation tube 12 is used which is surrounded by an elastically expandable body 17 which extends along the entire section of the separation tube 12 inserted into the container 2 (including volume compensation attachment 15 in this embodiment). Of course, here also deviating arrangements are conceivable. For example, also several elastically expandable bodies can be arranged circumferentially and/or axially distributed about and at the filling valve 1. Also, an arrangement of an elastically expandable body at one of the described filling valves without separation tube 1 is conceivable. And in a variant without volume compensation attachment 15, the elastically expandable body extends accordingly only along the entire section of the separation tube 12 inserted into the container 2. Type, number, and arrangement of the elastic expandable body or bodies depends on the latter being allowed to expand in step a1), after in step a) the closed filling valve 1 has been inserted completely into the container 2 which is sealed thereby, so that in step a2) it contacts the inner surfaces of the container 2 and, as in the illustrated example, the inner surface of the volume compensation attachment 15 and, at the same time, almost completely forces the ambient air (or another gas) present before in the container 2 through the pressure relief valve 16 present in the volume compensation attachment 15. The expansion of the elastically expandable body 17 can be effected by supply of an expansion fluid which can be a gas, but it is also conceivable that, after complete insertion of the filling valve 1 whereby gas has been displaced from the container, the filling tube 11 with the piston 10 in closed position is moved upwardly so that in the container 2 a vacuum is produced which causes expansion of the elastically expandable body 17. The latter is however possible only in containers that are sufficiently stable relative to external pressure; usually, beverage cans have a high strength regarding internal pressure but the external pressure resistance of unfilled cans is not very highempty cans can be relatively easily crushed. Therefore, the expansion by supply of an expansion fluid may be preferred.

(54) In the next b-steps, first the transfer of the piston 10 into the open position of the filling valve 1 is carried out so that fluid flows into the radial gap volume V between the container wall 20 and the filling valve 1 whereby the elastically expandable body 17 in step b1 a) is compressed until it is contacting again the separation tube 12 (step bib). When the gap volume V and the annular gap between the volume compensation attachment 15 and the filling valve 1 is filled, an upward movement of the filling tube 11 with the piston 10 in open position up to a predefined height H in a region of the container opening 21 is performed in the step b2) (not illustrated), wherein the separation tube 12 remains in the completely inserted position with the axial gap A so that the separation tube 12 is filled with fluid. The filling valve 1 in step d1) is closed when in step b2) the predefined height H in the region of the container opening 21 is reached. In step d2) the retraction of the separation tube 12 follows which here advantageously opens at the same time the seal 14 which is connected to the separation tube 12. Subsequently, the closed filling valve 1 in step e), not illustrated, is retracted from the completely filled container 2.

(55) The volume compensation attachment 15, which is also shown in FIG. 4, provides together with the annular gap 15, which is formed between the inner wall of the volume compensation attachment 15 and the separation tube 12, a volume which corresponds to a displaced volume that is caused by the portion of the filling valve 1 that upon closing of the filling valve 1 in step d1) is located within the container 2, which in this case is the separation tube 12. In this way, the fluid, which has flowed upon filling of the container 2, initially the gap volume V, in the steps b) and c) up to the annular gap 15 of the volume compensation attachment 15, can flow into the container 2 when opening the seal 14 by retraction of the separation tube 12 in step d2) so that the predefined filling volume is present in the container 2.

(56) The filling arrangement in accordance with the invention according to a further embodiment, which is illustrated in an exemplary fashion in FIG. 12, shows a volume compensation attachment 15 wherein here also a sealing element 14 is illustrated with which the volume compensation attachment 15 is sealed at the container opening 21 of the container 2. The above described embodiments with volume compensation attachment 15 can also be sealed with a suitable sealing element at the container opening 21.

(57) Moreover, the filling valve 1 illustrated in FIG. 12 comprises a filling tube 11 and a piston 10 which are furnished each with an exchangeable filling tip section 7, 8. These filling tip sections 7, 8 can be connected by any screwing, locking or plug-in mechanism, for example, also by a bayonet closure. With the exchangeable filling tips 7, 8, the filling valve 1 can be simply and quickly matched, for example, to containers with different bottom geometries. Moreover, by different filling tip sections, the outflow behavior of the fluid can be affected. Finally, the elimination of leaks by simple exchange of the filling tip sections can also be performed significantly more quickly.

(58) The centering section 19 which is present at the filling tip 8 of the piston 10 and tapers toward the end face can ensure an improved sealing action when the valve is closed because the sealing seats 11, 13 will always come to rest on each other with proper fit in this way.

(59) In order to enhance the centered guiding action of the piston 10 in the filling tube 11, the filling valve 1 has a radial spacer device 6 which in the illustrated example is comprised of a ring attached to the piston and from which spacer sections are radially projecting. Due to the section illustration, in FIG. 12 only one of these spacer sections can be seen which are arranged symmetrically about the center axis defined by the piston 10. The spacer sections of the spacer device 6 are in this context embodied such that they can glide along the inner side of the filling tube 11 when the piston 10 is moved up and down for opening and closing the valve 1. Preferably, a spacer device 6 can comprise three radial spacer sections which are symmetrically arranged at an angle of 120 relative to each other because in this way the centering action is ensured and in this way the flow cross section in the filling tube 11 is only minimally reduced. However, more than three radial spacer sections that are symmetrically arranged relative to each other can be provided. Different than illustrated, a radial spacer device can also be arranged at the inner side of the filling tube wherein the spacer sections are contacting glidingly the piston 10.

(60) It is noted that, different than illustrated, also filling valves according to the invention without exchangeable filling tip sections can be provided with centering section and/or spacer device. For example, the elements described in connection with FIG. 10, centering section 19, exchangeable filling tip sections 7, 8, and radial spacer device 6, must not mandatorily be realized in the illustrated combination but can also be individually present at filling arrangement or filling valve according to the invention. For example, a filling valve can have an exchangeable tip without the latter comprising a tapering centering section or radial spacer and without the filling arrangement comprising a sealed volume compensation attachment, etc. Also, these elements are not limited to a simple filling valve but can also be present at filling arrangements with separation tube, combined separation/filling tube, and with expandable body. The same applies also to the embodiments of the filling valve with flow guiding structure described in the following.

(61) In order to further improve the filling process and to achieve essentially laminar flow conditions so that the fluid level in the gap volume rises calmly and enclosed gas bubbles are avoided, a further embodiment of the invention provides that the filling valve 1 comprises a flow guiding structure 9 that imparts to the outflowing fluid a defined swirling or vortex movement. In this way, it is avoided that the fluid, which is exiting at filling pressure, impacts radially against the container wall and rebounds causing more gas bubbles to be enclosed which would accumulate to the end of the filling process and then cause a strong foaming action.

(62) The flow guiding structure, as shown in FIG. 13, can be present at an inner side of the filling tube 11 or, as shown in the examples of FIGS. 14 to 16, at an outer side of the piston 10 above the respective sealing surfaces 11, 13. Different than illustrated, flow guiding structures interacting with each other can be provided at both filling tube and piston, while the filling valve can also be a filling valve that opens outwardly or downwardly.

(63) The examples in FIGS. 13 and 14 show each in the filling tube 11 and at the piston 10 a flow guiding structure 9 that is formed by a coil web similar to a thread. Also, several parallel extending coil webs can be provided.

(64) FIGS. 15 and 16 show a vane structure as flow guiding structures at the outer side of the piston 10. Different than illustrated, a vane structure can also be provided at the inner side of the filling tube.

(65) The flow guiding vane structure 9 at the piston 10 in FIG. 15 is formed by an annular arrangement of guide vanes that are curved at least in two planes in order to impart a swirling or vortex movement to the fluid flowing past them.

(66) FIG. 16 shows an example in which the flow guiding vane structure 9 is formed by an annular arrangement of moving vanes that are uncurved here. In order to impart a swirling or vortex movement to the fluid passing them, the piston 10 is designed to be driven in rotation, as is indicated by the block arrow. When the moving vanes are curved, it is sufficient when the piston 10 is rotatably supported because the fluid flowing past the moving vanes will cause the piston 10 to rotate so that the swirling or vortex generation is assisted even without a drive.

(67) Advantageously, a flow guiding structure can be at the same time embodied as a radial spacer device or the radial spacer sections can be designed as flow guiding structure, i.e., in a vane shape.

(68) 35 It is noted that in the illustrated examples the opening direction of the filling valve is always illustrated with a movement of the piston inwardly or upwardly wherein the sealing seat at the piston points downwardly and the sealing seat at the filling tube upwardly. However, aside from the variant with combined separation/filling tube, in accordance with the invention also embodiments of filling valves are to be expressly encompassed which open in opposite direction, i.e., in which the piston for opening is moved downwardly for which purpose the piston tip comprises usually a plate-shaped widened end section in order to provide an upwardly facing sealing seat which can contact a corresponding downwardly facing sealing seat of the filling tube.

(69) It is apparent that, based on the basic principle of the invention, a plurality of different embodiments of the method are conceivable of which here only some have been explained in an exemplary fashion and which are not meant to limit the protection defined by the claims.

(70) Any modification which utilizes the basic principles of the invention is to be encompassed: According to the invention, the filling quantity determination is realized by means of the known geometries (volume) of the container (can) and of the filling valve that at the same time represents a displacement element. Various embodiments are conceivable for the filling valve. A filling valve according to the invention (with or without separation tube, expansion body . . . ) is matched with its outer diameter to the diameter of the container to be filled which exhibits only a minimal difference to the container diameter. Accordingly, in comparison to the prior art, expensive measuring devices such as MID sensors can be eliminated. Also, the control action of filling based on filling level, adjusted by the position of the opening of a return air pipe or of a return air bore or by means of sensor, actor or suitable control logic, can be dispensed with.

(71) With the geometric conditions of the filling arrangementthe size of the annular surface between container wall and filling valve is dependent on container diameter and container opening diameter and can therefore be also very smallthe contact surface reduction is realized that leads to a reduced gas absorption into the filled-in fluid. While in the prior art the ambient air present in the container is purged by carbon dioxide which causes a very high carbon dioxide consumption, the oxygen quantity is significantly reduced according to the invention already by the mechanical displacement of the air out of the container due to the geometric conditions, even in embodiments without expandable body. Due to the filling process below fluid level about the separation or filling tube, reduced or no turbulence of filled-in fluid and residual gas in the container is produced so that the oxygen absorption is further minimized. In the variant with the pumping step or post pressurization, with the transfer of the fluid into the gap volume further residual gas (and thus oxygen) is removed from the container through the pressure relief valve so that here also no oxygen absorption occurs. Moreover, a very quick filling process which in its realization is almost laminar can be obtained due to this post pressurization.

(72) Furthermore, the required pressure (counter pressure, saturation pressure, filling pressure) for counter pressure filling which in the prior art is generated by compressed gas, mostly carbon dioxide or nitrogen, can be provided mechanically by sealing the filling opening during insertion of the filling valve so that pressurization gas and corresponding devices for supply can be dispensed with. The desired pressure is adjustable in a simple way by determining the required insertion depth for given geometric conditions.

(73) Also, a counter pressure filling without return air tube is enabled so that the separate control action, cleaning, and maintenance of the return air tubes or return air conduits is not needed while still required in the prior art: Here usually the one-chamber principle for filling is employed. The container to be filled and a storage container at the filling device (annular reservoir) form together a chamber during the actual filling process. The liquid that is flowing into the container to be filled displaces the gas contained therein into the storage container. There are also multi-chamber solutions which however up to now have not found acceptance because the individual chambers can be separated properly only when a filling material loss is accepted. A true separation of the chambers can be done only with a complex apparatus structure with a balloon element or impermeable membrane.

(74) In summary, for filling containers such as cans, measuring means for monitoring the filling quantity as well as purging or pressurization gas can be dispensed with by means of the invention wherein the employed filling device is of a really simple construction and hardly prone to failure. Even though the invention preferably does not require purging and pressurization gas, performing such steps in the method according to the invention is not excluded.

(75) In this invention, known parameters are used that prior to, during, and after the filling process do not change. It is decisive that these parameters cannot be changed or controlled. The ambient pressure, the can volume, and the displacement volume of the filling valve remain constant and cannot be controlled. These parameters are determined at a suitable time (measured or calculated) and are used at a different point in time for pressure and (filling) volume determination during the filling process. These parameters are moreover used such that during the filling process at a predefined point in time a nominal pressure and/or a nominal volume can be adjusted solely by a relative movement of the individual parts (filling valve, seal, separation tube . . . ) along an axis in relation to the container.

LIST OF REFERENCE CHARACTERS

(76) 1 filling valve 10 piston 11, 11 filling tube, sealing seat 12 separation tube 13 sealing seat/contact surface 14, 14 sealing element 15, 15 volume compensation attachment 16 valve 16 gas discharge conduit 17 elastically expandable body 18 unilaterally acting annular seal, sealing lip 19 centering section 100 wide piston 112 combined separation/filling tube 2 cylindrical container, can 20 container wall 21 container opening 22 container bottom 6 radial spacer 7 exchangeable filling tube filling tip section 8 exchangeable piston filling tip section 9 flow guiding structure d.sub.Fa outer diameter filling device d.sub.Fi inner diameter filling tube d.sub.K piston diameter d.sub.Di container interior diameter d.sub.Do inner diameter container opening A axial gap H predefined height h, h.sub.max filling level in gap volume, maximum s gap width in gap volume V.sub.D container volume V.sub.V displacement volume V.sub.F inserted filling valve volume V radial gap volume p.sub.0 ambient pressure p container pressure