APPARATUS AND METHOD FOR TREATING CONTAINERS

Abstract

An apparatus for treating containers includes a fixed machine element, a rotating machine element, first and second walls that delimit an interior. The first wall is part of the fixed machine element and the second wall is part of the rotating machine element. A labyrinth seal is formed between the first and second walls, the labyrinth seal has an annular slit that forms a channel. The channel has an inner end that faces the interior and an outer end that faces away from the interior. An underpressure source comprising a blade is at the outer end. Rotation of the underpressure source causes the blade to generate an underpressure in the labyrinth seal. This underpressure generates gas flow from the inner end to the outer end.

Claims

1-15. (canceled)

16. An apparatus for treating containers, said apparatus comprising a fixed machine element, a rotating machine element, first and second walls that delimit an interior, a labyrinth seal formed between said first and second walls, said labyrinth seal comprising an annular slit that forms a channel, said channel having an inner end that faces said interior and an outer end that faces away from said interior, and an underpressure source at said outer end, said underpressure source comprising a blade, wherein rotation of said underpressure source causes said blade to generate an underpressure in said labyrinth seal, and wherein said underpressure generates gas flow from said inner end to said outer end and wherein said first wall is part of said fixed machine element and said second wall is part of said rotating machine element.

17. The apparatus of claim 16, wherein said rotating machine element rotates about a first axis of rotation, said underpressure source rotates about a second axis of rotation that coincides with said first axis of rotation.

18. The apparatus of claim 16, wherein said underpressure source is securely connected to said rotating machine element.

19. The apparatus of claim 16, further comprising a drive, wherein said drive rotates said underpressure source.

20. The apparatus of claim 16, wherein said blade is curved.

21. The apparatus of claim 16, wherein said blade is one of a plurality of rotatable blades, wherein each of said blades is mounted to rotate relative to a bearing.

22. The apparatus of claim 16, further comprising an inclination adjuster that adjusts an inclination of said blade.

23. The apparatus of claim 16, further comprising a cover that covers at least a portion of said outer end.

24. The apparatus of claim 16, further comprising a cover, wherein said cover is securely connected to said underpressure source.

25. The apparatus of claim 16, further comprising a passage having a first end and a second end, wherein said first end is located at said outer end, and wherein said first end is subjected to said underpressure.

26. The apparatus of claim 16, further comprising a filter and passage through which air is drawn towards said outer end by said underpressure, said air having passed through said filter before reaching said outer end.

27. The apparatus of claim 16, further comprising a passage through which ambient air is drawn towards said outer end by said underpressure.

28. The apparatus of claim 16, further comprising a passage having an opening connected to a reservoir of sterile gas, wherein said underpressure draws sterile gas from said reservoir through said passage and towards said outer end.

29. The apparatus of claim 16, further comprising a line that leads into said interior for delivering sterile gas into said interior.

30. The apparatus of claim 16, wherein said blade moves along a circular path defined by said rotating machine element and said blade is rotatable to form an angle relative to said circular path.

31. A method comprising treating containers with an apparatus that comprises a fixed machine element, a rotating machine element, first and second walls that delimit an interior, a labyrinth seal formed between said first and second walls, said labyrinth seal comprising an annular slit that forms a channel, said channel having an inner end that faces said interior and an outer end that faces away from said interior, and an underpressure source at said outer end, said underpressure source comprising a blade, wherein rotation of said underpressure source causes said blade to generate an underpressure in said labyrinth seal, and wherein said underpressure generates gas flow from said inner end to said outer end and wherein said first wall is part of said fixed machine element and said second wall is part of said rotating machine element, said method comprising causing said underpressure source to draw air from said interior through said labyrinth seal from said inner end to said outer end.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0028] The invention is explained in greater detail hereinafter on the basis of the Figures relating to exemplary embodiments. The Figures show:

[0029] FIG. 1 is a schematic section through a container-treatment machine;

[0030] FIG. 2 is a view of an embodiment of a labyrinth seal with an alternative underpressure generating device having a passage;

[0031] FIG. 3 is a view of another underpressure generating device;

[0032] FIG. 4 shows an underpressure generating device having its own motor;

[0033] FIG. 5a is a side view of a blade element's curve; and

[0034] FIG. 5b shows an inclination-adjustment device to adjust inclination of a group of blade elements.

[0035] Identical reference numbers are used in the figures for elements of the invention which are the same or have the same effect. Moreover, for the sake of easier overview, only reference numbers are represented in the individual figures which are required for the description of the respective figures.

DETAILED DESCRIPTION

[0036] FIG. 1 shows a container-treatment machine 1, examples of which include a rinsing machine, a sterilizer, a filling machine, and aa closing machine. The containers 2 shown in FIG. 1 are bottles. However, other types of containers 2 can be used, such as cans.

[0037] During treatment, the containers are in a sterile interior 3. This is useful for cold aseptic filling of heat-sensitive beverages such as, for example, fruit juices.

[0038] Only the relevant components of the container-treatment machine 1 are shown. These include a fixed element 4 and a rotating element 5. The rotating element 5 comprises holders 6 that hold the containers 2 during transport thereof by the rotating element 5 about a first axis RA1.

[0039] A first wall 7, which is assigned to the positionally fixed machine element 4, and a second wall 8 delimit an interior 3. The first wall 7 is that of the fixed element 5 and the second wall 8 is that of the rotating element 5, delimit the interior 3.

[0040] A labyrinth seal 9 between the first and second walls 7, 8 inhibits flow of non-sterile ambient air into the interior 3. To further inhibit such flow, it is useful to maintain the interior 3 at a pressure that is higher than that of the ambient air. This drives sterile air outward through the labyrinth seal 9, thus discouraging flow of air inwards. A gas line, which is omitted for clarity from FIG. 1 but shown in FIG. 4, brings new sterile air to replace this lost sterile air.

[0041] An annular slit 10 that forms a channel through the labyrinth seal 9. This creates a tortuous flow path for air and thus increases flow resistance between the interior 3 and the exterior. This increased flow resistance reduces flow of sterile gas outward, thus reducing the required volume of replacement sterile gas. The annular slit 10 extends between an inner end 11, which faces the interior 3, and an outer end 12, which faces away from the interior 3.

[0042] The container-treatment machine 1 also includes a rotatable underpressure source 13 arranged in the region of the outer end 12. In the illustrated embodiment, the underpressure source 13 is part of the rotating element 5. The rotatable underpressure source 13 comprises one or more blades 14. As a result of being rotated, the blades 14 generate an underpressure that draws sterile air from interior 3 through the labyrinth seal 9 from the inner end 11 to the outer end 12. This further impedes ingress of non-sterile ambient air into the sterile interior 3.

[0043] FIG. 2 shows a section through a further container-treatment machine 1 for treating containers 2, in the region of the labyrinth seal 9. The embodiment shown includes a cover 15 that is securely connected to the fixed element 4, and that covers at least sections of the outer end 12. The resulting partial covering of the outer end 12 further impedes a penetration of non-sterile air into the interior 3.

[0044] The embodiment shown in FIG. 2 further includes a passage 16 having an upper opening that lies near the outer end 12 and a lower opening 17 into ambient air. The passage 16 is likewise covered by the cover element 15.

[0045] Operation of the underpressure source 13, i.e. by rotating the rotating element 5, subjects the passage 16 to an underpressure. This draws ambient air through the lower opening 17 and results in a gas flow through the passage 16. The resulting directed flow also impedes entry of non-sterile air into the interior 3.

[0046] Some embodiments include a filter pack 30 at the lower opening 17 to prevent drawing foreign bodies or contaminants substances into the region of the labyrinth seal 9. In an alternative embodiment, the opening 17 connects to a reservoir of sterile gas or air.

[0047] In the embodiment shown in FIG. 3, the cover element 15 forms a part of the underpressure source 13. A screw 18 forms a detachable connection between the underpressure source 13 and the rotating element 5.

[0048] The cover 15 comprises slits 19 that are arranged on a side edge near the blade 14. Underpressure generated resulting from rotation of the blades 14 causes a gas flow that is directed outwards through the opening slits 19. This also results in an underpressure at the outer end 12. This embodiment allows for the formation of defined flow conditions in the region of the outer end 12 of the labyrinth seal 9 and therefore provides good protection against the ingress of non-sterile ambient air into the sterile interior 3.

[0049] FIG. 4 shows an embodiment in which a separate motor 30 rotates the underpressure source 13 about a second axis RA2. The embodiment shown in FIG. 4 makes it possible for the underpressure source 13 to be rotated independently of the rotating element 5. This permits the blades 14 to rotate more rapidly than the rotating element 5, thus generating a more powerful underpressure in the region of the outer channel end 12. Preferably, the first and second axes RA1, RA2 coincide.

[0050] An underpressure source 13 with its own drive 20 is particularly advantageous if the rotating element 5 must be stopped briefly for operational reasons. In this case, the drive 20 can continue to rotate underpressure source 13 and thus maintain the desired gas flow conditions in the region of the outer end 12.

[0051] FIG. 4 also shows line 21 having an outlet 22 that opens into the interior 3. The line 21 provides a way to introduce sterilizing medium into the interior 3 at intervals or as required to re-establish or maintain sterile conditions in the interior 3.

[0052] In the view shown in FIG. 5a, it is possible to see a curve in the blade 14. The shape of the curve provides a way to cause an aerodynamic interaction that results in attainment of a desired underpressure at the outer end 12 or attainment of a nearly constant underpressure.

[0053] FIG. 5b shows a group of blades 14, each of which has a proximal end and a distal end. The proximal end couples to a bearing 23 to permit rotation relative to the bearing 23. The distal end couples to a link 25. A rod 24 extends to connect all of the links 25. This results in inclination adjuster 26 that adjusts the inclination of the blades 14. The inclination of the blades 14 provides a way to control underpressure in the labyrinth seal 9 or the desired gas flow from the inner end 11 to the outer end 12.

[0054] In some embodiments, a motor controls the adjustment device 26, either hydraulically or pneumatically. Some embodiments provide automatic control of the inclination of the blades 14 based on feedback, based on the rotation speed of the underpressure source 13, the pressure difference between the interior 3 and surrounding environment, and/or the degree of contamination of the ambient air.

[0055] The invention has been described heretofore on the basis of exemplary embodiments. It is understood that a large number of variants or derivatives are possible, without thereby departing from the scope of protection of the invention defined by the claims.