APPARATUS AND METHOD FOR FILLING PRODUCT INTO CONTAINERS

Abstract

An apparatus for filling product into containers includes a working chamber through which the containers pass and the containers are acted upon by a sterile fluid to avoid contamination. An external line extends through the working chamber having a plurality of gas openings for the introduction of sterile air into the working chamber and that an internal line extends into the external line having a plurality of openings for spraying a cleaning medium. An annular chamber extends in a longitudinal direction between the internal and the external line. The cross-sectional area of the annular chamber varies in the longitudinal direction so that an even distribution of sterile air emerging from the gas openings into the working chamber is achieved.

Claims

1.-22. (canceled)

23. An apparatus, comprising: a working chamber through which the containers are conveyed in a longitudinal direction of the working chamber from an inlet side to an outlet side; at least one station in the working chamber which executes a working step on the containers; an external line configured as a gas distribution pipe extending through the working chamber and having a plurality of openings for introducing a sterile fluid into the working chamber to create a sterile atmosphere in the working chamber; an internal line configured as a spray pipe extending into the external line and having a plurality of openings for spraying a cleaning medium; an annular chamber having a closed end, extending in the longitudinal direction, and being defined between the internal line and the external line; and an inlet for supplying the sterile fluid into the annual chamber, the inlet predefining a flow direction in the annular chamber for the sterile fluid starting from the inlet toward the closed end, wherein a cross-sectional area of the annular chamber varies in the longitudinal direction, at least in sections of the annular chamber.

24. The apparatus according to claim 23, wherein the working chamber is divided in the longitudinal direction into a sterilizing region proximate the inlet side and a filling region distal from the inlet side, the sterilizing region being separated from the filling region by a separation wall extending transversely to the longitudinal direction, the at least one station comprises a filling station for filling the containers with a product, the filling station disposed in the filling region, and the cross-sectional area of the annular chamber varies in the longitudinal direction substantially over an entire length of the filling region.

25. The apparatus according to claim 24, wherein the cross-sectional area of the annular chamber varies linearly substantially over the entire length of the filling region.

26. The apparatus according to claim 23, wherein the cross-sectional area of the annular chamber decreases in the flow direction.

27. The apparatus according to claim 24, wherein a cross-section of the external line is constant over an entire length of the working chamber.

28. The apparatus according to claim 27, wherein a cross-section of the internal line increases substantially over the entire length of the filling region in the longitudinal direction.

29. The apparatus according to claim 23, wherein the external line and the internal line are rotatable relative to one another about longitudinal axes thereof.

30. The apparatus according to claim 23, further comprising at least one profile provided with openings extending over the containers disposed in the working chamber, the at least one profile distributing the sterile fluid introduced by the external line over the containers.

31. The apparatus according to claim 30, wherein each the at least one profile is rotatable about an axis between a first operating position, when containers are present in the working chamber, and a second cleaning position, when no containers are present in the working chamber.

32. The apparatus according to claim 29, wherein the internal line is rotatable in the external line to at least one closed position in which at least one closure element closes the openings in the inner line with respect to the annular chamber.

33. The apparatus according to claim 24, wherein the external line in the flow direction upstream of the filling region has no openings for the introduction of a sterile fluid into the working chamber.

34. The apparatus according to claim 24, further comprising at least one flow body disposed in the filling region configured to provide a flow resistance to the sterile fluid emerging from the openings of the external line.

35. The apparatus according to claim 34, further comprising at least one profile provided with openings extending over the containers disposed in the working chamber, which distributes the sterile fluid introduced by the external line over the containers, wherein the at least one profile is rotatable about an axis between a first operating position and a second cleaning position, each the at least one flow body filling the free cross-section of the working chamber in the filling region above each the at least one profile, when the at least one profile is located in the first operating position.

36. The apparatus according to claim 34, wherein the at least one flow body is disposed in the flow direction upstream of the filling station in the filling region.

37. A method comprising the steps of: introducing a sterile fluid into a working chamber using an external line configured as a gas distribution pipe having a plurality of openings and extending through the working chamber; conveying containers in a longitudinal direction through the working chamber; performing at least one working step on the containers in a sterile atmosphere; introducing a cleaning medium through an internal line configured as a spray pipe having a plurality of openings, the internal line extending into the external line, and spraying the cleaning medium into an annular chamber which extends in the longitudinal direction between the internal line and the external line; and supplying the sterile fluid in a flow direction in the annular chamber, a cross-sectional area of the annular chamber varying at least in sections in the longitudinal direction.

38. the method according to claim 37, wherein the working chamber is divided by a separation wall into a sterilizing region and a filling region, the step of performing at least one working step includes filling the containers in the filling region, and the step of supplying the sterile fluid is performed in a flow direction in the annular chamber, wherein the cross-sectional area of the annular chamber varies in the longitudinal direction over the entire length of the filling region.

39. the method according to claim 37, wherein the working chamber is divided by a separation wall into a sterilizing region and a filling region, the step of performing at least one working step includes filling the containers in the filling region, and the step of supplying the sterile fluid is performed in a flow direction in the annular chamber, wherein the cross-sectional area of the annular chamber decreases linearly in the longitudinal direction over the entire length of the filling region.

40. the method according to claim 37, wherein the internal line and the external line are rotated at least temporarily relative to one another about longitudinal axes thereof during the step of introducing the cleaning medium through the internal line.

41. the method according to claim 37, wherein the sterile fluid introduced by the external line is distributed over the containers in the working chamber by at least one profile with openings.

42. the method according to claim 41, wherein the at least one profile is rotated from a first position, in which sterile fluid is introduced into the working chamber, to a second position, in which the cleaning medium is applied.

43. the method according to claim 37, wherein the openings in the internal line are closed during the step of introducing of the sterile fluid into the working chamber.

44. the method according to claim 37, wherein a flow resistance to the sterile fluid introduced in the filling region of the working chamber is provided by a flow body during the step of introducing the sterile fluid.

Description

[0028] The invention is explained in greater detail below on the basis of the figures:

[0029] FIG. 1 shows a schematic partial longitudinal cross section through a filling machine;

[0030] FIG. 2A) shows an enlarged cross section through an internal line and an external line extending through the filling machine shown in FIG. 1;

[0031] FIG. 2B) shows an enlarged partial cross section through the internal line and the external line extending through a sterilzing region of the filling machine shown in FIG. 1; and

[0032] FIG. 2C) shows an enlarged partial cross section through the internal line and the external line extending through a filling region of the filling machine shown in FIG. 1.

[0033] The filling machine 1 comprises a sterile working chamber 2, having the form of a hollow substantially rectangular block.

[0034] Containers 3 designed to hold beverages are conveyed from an inlet side 4a to an outlet side 4b of the working chamber 2 along at least one conveying path in a longitudinal direction 5 of the working chamber 2 by means of an endless conveyor 2a.

[0035] Proceeding from the inlet side 4a, the working chamber 2 is divided along the length of the working chamber into a sterilizing region 6 and a filling region 7. The sterilizing region 6 is separated from the filling region 7 by a separation wall 8 extending transversely to the longitudinal direction 5.

[0036] The sterilizing region 6 starting from the inlet side 4a comprises a pre-heating zone 6a, a sterilization zone 6b and a drying zone 6c. The adjoining filling region 7 comprises a filling zone 7a and a closure zone 7b. The filling of the liquid foodstuffs into the containers 3 pre-treated in the sterilizing region 6 takes place in the filling zone 7a by means of a filling station 15. The filled containers 3, which have been open until now, subsequently enter into the closing zone 7b in which the containers 3 are closed.

[0037] Feed elements for hot air, hydrogen peroxide and optionally for a process gas such as nitrogen dioxide to prevent oxidation of the beverage project from the ceiling of the working chamber 2 into the different zones 6 a, b, c of the sterilizing region 6.

[0038] At least one external line 9 configured as a gas distribution pipe for sterile air is arranged under the ceiling of the working chamber 2 concentric to the longitudinal axis of an internal line 10 configured as a spray pipe for a cleaning medium. The external line 9 and the internal line 10 extend through the entire working chamber 2 from the inlet side 4a to the outlet side 4b. In a vertical projection the external line 9 is located offset to the left or right of the conveying path of the containers 3.

[0039] Each external line 9 has a plurality of gas openings 9a, which are distributed uniformly over the section of the external line 9 extending through the filling region 7 and also uniformly around its circumference. On a line parallel to the longitudinal axis of the external line 9 extending through the sterilzing and filling region 6,7, some openings 9b are present which are larger than the gas openings 9a. On a line parallel to the longitudinal axis of each internal line 10, several cleaning medium openings 10a of fan jet nozzles are arranged on the lateral surface of the external line 10. The size and contour of the cleaning medium openings 10a agree approximately with the size and contour of the openings 9b in the external line 9.

[0040] An annular chamber 11 extends in the longitudinal direction 5 between the internal line 10 and the external line 9 having a closed end 11a at the outlet side 4b of the working chamber 2.

[0041] An inlet 12 for supplying sterile air into the annular chamber 11 is arranged on the opposite end of the annular chamber whereby a flow direction of the sterile air starting from the inlet 12 towards the closed end 11a of the annular chamber 11 is defined.

[0042] On one side 10b, the internal line 10 is sealed off at its end. On the opposite side, the internal line is connected to a supply for the cleaning medium to the interior of the internal line 10.

[0043] The external line 9 and the internal line 10 are able to rotate independently of each other around their longitudinal axes by means of a drive, installed at one end outside the working chamber 2.

[0044] Below the external line 9 and above a filling plane for the containers 3 profiles 13, configured as flat perforated plates are mounted on a driven shaft. These perforated plates can be rotated out of the horizontal operating position shown in FIG. 1 into a cleaning position and vice versa. The whole-area coverage by the perforated plates in the filling region 7 when in their operating position has the result of optimally distributing the sterile air supplied through the external line 9 in the filling plane located underneath the perforated plates.

[0045] In order to achieve an even distribution of sterile air, a uniform pressure distribution and a uniform flow velocity of the sterile fluid in the particularly critical filling region 7, the cross-section area 11b of the annular chamber 11 varies substantially over the entire length of the filling region 7 in the longitudinal direction 5. As best shown in FIG. 2 c the cross-sectional area 11b of the annular chamber 11 decreases linearly in the flow direction towards the closed end 11a of the annular chamber 11. The reduction of the cross-sectional area 11b counteracts the increase in the static pressure towards the closed end 11a of the annular chamber 11. Simultaneously the flow velocity is becoming more even.

[0046] For construction reasons the circular cross-section 9c of the external line 9 configured as a pipe is uniform over the entire length of the working chamber 2. The linear variation of the cross-sectional area 11b of the annular chamber 11 is achieved by the internal line 10 configured as a pipe which diameter increases substantially over the entire length of the filling region 7.

[0047] Under certain operation conditions the sterile air emerging from the gas openings 9a in the external line 9 still may have a high flow velocity in the longitudinal direction 5 of the working chamber 2, resulting in turbulence in the working chamber 2 and an area within the filling region 7 behind the separation wall 8 with a too low static pressure. This too low static pressure may cause a back-flow of the sterile air through the perforated plates 13. In order to avoid turbulence and locally a too low static pressure in one embodiment of the invention a flow body 14 is disposed between the separation wall 8 and the filling station 15 in the filling region 7, which offers a flow resistance to the sterile fluid emerging from the openings 9a of the external line 9. The said flow body 14 is an additional wall arranged in a parallel distance from the separation wall 8 filling the free cross-section of the working chamber 2 in the filling region 7 above the perforated plate 13 when this is located in the horizontal working position as shown in FIG. 1. This additional wall creates an additional chamber within the filling zone 7a limiting the flow of sterile air in this zone and thereby reducing turbulence and increasing the static pressure.

[0048] Additionally under such operation conditions it may be advisable to limit the spill-over of sterile air from the sterilization region 6 to the filling region 7 by providing sealing elements which more fully close the separation wall 8 between the two regions 6,7.

[0049] The filling machine operates during the filling of containers 3 with beverages and during the following cleaning process with a cleaning medium as follows:

[0050] A conveyor 2a conveys a plurality of containers 3 simultaneously into the preheating zone 6a first, in which all of the containers 3 are treated simultaneously with the hot air. Then the containers 3, thus heated with hot air, advance to the sterilization zone 6b, where they are treated with hydrogen peroxide. In the next step of the process, the containers 3 are sent to the drying zone 6c, where the hydrogen peroxide is dried off with air. The sterilized containers 3 leaving the sterilizing region 6 now advance to the filling zone 7a, where they are filled with beverages simultaneously through feed elements of the filling station 15, before the top flaps, which are oriented parallel to the conveying path are mechanically closed by guide profiles in the following closure zone 7b and then heated and pressed together by sealing tools 7c. Finally, the now sealed containers 3 leave the working chamber 2 at the outlet side 4b.

[0051] In order to maintain a clean-room atmosphere in the working chamber 2 until the containers 3 have been sealed in the closure zone 7b, sterile air, which flows out into the working chamber 2 through the gas openings 9a, is supplied continuously through the external line 9. The external line 9 configured as a pipe with uniform circular cross-section 9c together with the internal line 10 configured as a pipe which diameter increases substantially over the entire length of the filling region providing a constant pressure distribution and an even distribution of the sterile air emerging from the gas openings 9a within the filling region 7a.

[0052] After completion of the filling and conveying of a large number of containers 3 through the working chamber 2, the filling machine 1 must be cleaned completely before the next filling operation. For this purpose, the internal line 10 is supplied with cleaning medium, which emerges through the cleaning medium openings 10a arranged in a straight line. During the cleaning process the internal line 10 rotates around its longitudinal axis. The larger openings 9b in the external line 9 are aligned with cleaning medium openings 10a of the fan jet nozzles of the internal line 10 to ensure the unhindered outflow of the cleaning medium during the cleaning operation. The external line 9 rotates synchronously with the internal line 10 in the same direction, so that the cleaning medium openings 10a remain aligned with the larger openings 9b during the entire cleaning operation.

[0053] Finally the rotation of the external line 9 is stopped and/or its rotational direction reversed to ensure that the cleaning medium emerging from the cleaning medium openings 10a is distributed over the entire inside surface of the external line 9.

[0054] So that the areas underneath the perforated plates 13 can also be cleaned effectively during the cleaning of the working chamber 2, the perforated plates are pivoted into a vertical cleaning position during the cleaning operation. To clean the perforated plates 13 themselves on all sides, these plates 13 are pivoted 360 degrees at least once, preferably several times, so that all surfaces of the perforated plates 13 are exposed at least once directly to the cleaning medium emerging from the cleaning medium openings 10a.