Filling machine with sterilization station

Abstract

A filling machine (10) configured to form, fill and seal individual packages (4) is provided. The filling machine comprises a sterilization station (100) configured to provide a flow of a gaseous sterilizing agent towards an open end of a to-be-filled packaging container (4) passing through the sterilization station (100). The filling machine comprises at least one clean air supply (150) and at least one baffle (138) arranged above the at least one clean air supply, wherein the air supply (150) is configured to direct a flow of clean air towards the to-be-filled packaging container (4), the clean air supply (150) in turn comprising at least one distribution pipe (150) and wherein the distribution pipe (150) extends in a horizontal direction, which is the direction of the packaging flow through said filling machine (10).

Description

TECHNICAL FIELD

[0001] The present invention relates to a filling machine, in particular to a filling machine configured to form, fill and seal individual packages. The present invention also relates to a method for such a filling machine. BACKGROUND

[0002] In the food industry, beverages and other products are often packaged in paper- or paperboard-based packages. Packages for liquid food products are often made from a packaging laminate comprising a paper or paperboard core layer, and a liquid-impermeable outer layer of thermoplastic material at least on the side of the core layer that will form the inside of the package.

[0003] A frequently occurring package is the so-called ready-to-fill package. Such a ready-to-fill package is provided as a sleeve of packaging laminate as described above, sealed at the bottom end before filling. The upper end can be formed by forming and sealing the upper end of the sleeve or by producing an upper part in the form of e.g. a polymer top; the upper end / upper part can be provided with opening / closing means, such as a screw cap.

[0004] Another type of package that can also be used with the invention described herein is produced in an inverted configuration, sealed at the top (which is arranged downwards) and having the bottom open for filling. Typically, the downwards pointing top is produced as a polymer top.

[0005] Irrespective of the type of package produced, the end- open packaging material sleeve is received at an infeed station of the filling machine, and then one end of the sleeve is sealed; the semi-finished package now has the shape to be filled. However, further processes are required to provide a hygienic package. At a downstream station, the open sleeve is at least internally sterilized in order to prolong the shelf life of the product to be stored in the package. Different levels of sterilization can be obtained, depending on the required shelf life and depending on whether the package is to be distributed and stored in a refrigerated environment or at room temperature. Sterilization is performed using a gaseous sterilizing agent, such as H2O2.

[0006] After sterilization of the packages, they are further transported to a filling area for product filling, to a sealing area for sealing the open end, and typically also to a final shaping area for final shaping of the package.

[0007] Transport of the packages is achieved by a series of carriers guided along a conveying path. The conveying path preferably passes continuously through the filling machine, such that the flow of packages moves through the filling machine and all required stations.

[0008] After sterilization of the ready-to-fill packages, it is important to maintain hygienic conditions, as the packages are filled and sealed by subsequent stations. Therefore, these filling machine stations are installed in a hygienic zone, in order to ensure minimal re-contamination of the sterilized packages.

[0009] In the above machine, the conveying system inside the hygiene chamber of the packages to be filled is kept at a relatively low temperature due to i) the cold environment in the hygiene chamber and ii) due to the lubrication of the conveying system by the cooling water.

[0010] During the sterilization process, the dew point of the H2O2 gas needs to be very high to ensure that H2O2 condenses on the entire inner surface of the packages to be filled. Consequently, the high dew point of the gas will also cause a significant amount of condensed H2O2 on the conveying system as well as on the outer surface of the packages.

[0011] The condensed H2O2 on the conveying system and on the outer surface of the packages will then be transported through the filling machine. As the condensation film slowly evaporates along the movement around the entire conveying system, emissions of H2O2 will occur from the filling machine openings; the infeed opening where the blanks are fed to the filling machine; and the outfeed opening where the formed, filled and sealed packages are discharged from the machine.

[0012] Furthermore, this will result in a significant enrichment of H2O2 in the entire filling machine, also in areas where there can be machine components that are not specifically designed to be compatible with H2O2 exposure. This can result in, for example, corrosion of such components or a shortened service life thereof.

[0013] Another problem is associated with machine downtime. During machine stoppage, access to the filling machine is preferably not allowed until the H2O2 has been evaporated and ventilated, resulting in a delay time.

[0014] In view of the above-mentioned disadvantages associated with the use of sterilizing agents, such as gaseous agents, like H2O2, there is a need to reduce the condensation of H2O2 on the conveying system and on the outer surface of the packages during the sterilization process, while still maintaining a controlled and sufficiently high concentration of the sterilizing agent inside the packages. SUMMARY

[0015] It is an object of the present invention to at least partly overcome one or more of the above-mentioned limitations of the prior art. In particular, it is an object to provide a filling machine that is able to ensure the required sterilization of the packages to be filled, while reducing the unwanted condensation and evaporation of gaseous sterilizing agents.

[0016] To solve these problems, a filling machine is provided. The filling machine is configured to form, fill and seal individual packages, whereby the filling machine comprises a sterilization station configured to provide a flow of a gaseous sterilizing agent towards an open end of a packaging container to be filled passing said sterilization station. The filling machine further comprises at least one clean air supply arranged in a vertical position below said open end of the packaging container to be filled and configured to direct a flow of clean air, preferably filtered or sterile air, towards the packaging container to be filled. Preferably, the clean air supply extends in machine direction past the position of the gaseous sterilizing agent supply.

[0017] The clean air supply can comprise at least one distribution pipe, whereby the clean air can be distributed in an efficient manner.

[0018] The distribution pipe can extend in a horizontal direction, which is the direction of the flow of packages through the filling machine.

[0019] The distribution pipe can be provided with a plurality of outlet holes distributed in a longitudinal direction of the distribution pipe. The outlet holes can be directed upwards and inwards towards the packaging container to be filled.

[0020] The filling machine can further comprise at least one baffle arranged vertically above the at least one clean air supply. The baffle is preferably arranged horizontally, with the advantage that several clean air jets merge into a planar jet. The baffle also provides a physical separation of the gaseous environment above the baffle from the clean air environment below the baffle to avoid mixing of the two. Thus, dilution of the gasses above the baffle is avoided, and thus a high concentration of gas can be maintained around the gas jets (i.e. the gas supplies), so that the jets and thus the gas in the packages are not diluted. Some of this is described in lines 14-17 of sheet 6, but here the plate is key.

[0021] Furthermore, the clean air jets are directed towards the baffle to achieve so-called "wall attachment", whereby wall jets are created. These wall jets will act as rectangular jet-like structures on the baffle, thereby protecting the open surface between the baffles. This protection of the open surface will reduce the gas flow in vertical direction from the gas supply nozzles, whereby more gas flow in horizontal direction is directed towards the downstream holding section, thereby helping to maintain the packages in the gaseous environment.

[0022] The small gas flows directed vertically between the baffles are proven to be more concentrated to the central plane, whereby the flows around a larger part of the package carrier surface are diluted by the clean air flows to avoid high concentration of gas at these areas.

[0023] The filling machine can comprise a first distribution pipe arranged on one side of the packaging to be filled, and a second distribution pipe arranged on the opposite side of the packaging to be filled.

[0024] The clean air supply can be configured to provide a planar jet of clean air toward the package to be filled, preferably by means of a baffle.

[0025] The filling machine may include multiple indexing positions for supplying gaseous sterilizing agent to multiple packages to be filled, wherein a clean air supply extends through the indexing position in the form of one or more distribution tubes.

[0026] Clean air supply units can be connected to air supply systems used for downstream ventilation devices.

[0027] According to a second aspect, a method for sterilizing a package to be filled is provided. The method includes a first step of supplying a gaseous sterilizing agent toward the interior of the package to be filled, and a second step of providing a clean airflow (preferably a filtered and / or sterile airflow) toward the outer surface of the package to be filled.

[0028] The step of providing a clean airflow toward the outer surface of the package to be filled may include directing multiple clean air jets toward a baffle to provide a planar jet of clean air.

[0029] Other objects, features, aspects and advantages of the invention will become apparent from the following detailed description and the accompanying drawings. Attached Figure Description

[0030] Embodiments of the invention will now be described by way of example with reference to the accompanying schematic diagrams, wherein:

[0031] Figure 1 This is a schematic diagram of a filling machine according to one embodiment;

[0032] Figure 2 It is a schematic isometric view of a sterilization station that forms part of a filling machine according to one embodiment;

[0033] Figure 3 This is a cross-sectional view of a sterilization station forming part of a filling machine according to one embodiment;

[0034] Figure 4 It is a schematic isometric view of a dispensing pipe forming part of a filling machine according to one embodiment;

[0035] Figure 5 It is a schematic diagram of a method according to one implementation scheme; and

[0036] Figures 6a to 6c This is a simulation diagram of a sterilization station during operation, which is part of a filling machine according to one embodiment. Detailed Implementation

[0037] refer to Figure 1, a filling machine 10 is schematically illustrated. Although the filling machine described hereinafter is configured to produce carton-based packages by closing the bottom end of a tube of packaging material and eventually closing the upper end thereof after sterilization and filling, the filling machine 10 can also be configured to produce other types of packages, such as plastic top packages briefly described in the background section of the present application.

[0038] The filling machine 10, which is configured to form, fill and seal packages 4, has an infeed station 12, wherein blanks 2 of packaging material are received. The blanks 2 are typically produced as sleeves of carton-based packaging material, as is well known in the art and has been briefly described in the background section. The infeed station 12 is arranged upstream of a bottom sealing station 14, wherein the blanks 2 are erected into a tubular shape, in the bottom sealing station 14, the bottom end of each blank is sealed to form a semi-finished package having one closed and sealed bottom end, while the upper end of the package is still open.

[0039] The semi-finished packages are transported to a sterilization station 100, in which the amount of live microorganisms is reduced. As explained in the background section, the level of sterilization can vary depending on the user target. The sterilization of the packaging material is accomplished by means of a treatment with a gaseous sterilizing agent [preferably H2O2 (hydrogen peroxide)].

[0040] The sterilization station 100 comprises an upstream supply station 110, which provides a flow of gaseous sterilizing agent. A discharge station 120 is arranged downstream of the supply station 110.

[0041] A hygiene cell is arranged downstream of the sterilization station 100. The hygiene cell comprises other stations of the filling machine. Arranged immediately downstream of the sterilization station 100 is a filling station 30. Here, the to-be-filled packages are filled with the desired product content. After filling, the packages can be transported to a pre-folding station 32, in which the upper part of the end-opened packages is formed into the desired shape. After pre-formation, the packages are transported to a heating station 34, in which the heat-sealable material of the packaging material is heated to an elevated temperature. The elevated temperature of the upper end of the packages facilitates the sealing of the upper end when the packages enter a sealing station 36, which is arranged immediately after the heating station 34.

[0042] Once sealed, the packages 4 no longer require hygienic conditions as they exit the hygiene cell. At the end of the filling machine 10, a discharge station 16 is arranged, which is configured to discharge the finished packages 4 from the filling machine 10 to downstream equipment, storage and / or transport.

[0043] Figure 2A sterilization station 100 is further shown. It can be seen that the sterilization station 100 has the shape of a tunnel. The packages to be filled (not shown) are fed into the sterilization station 100 from the left-hand side of the figure. The packages to be filled are conveyed by a conveyor comprising a plurality of successive magazines; each magazine carries the packages to be filled. For the sake of illustration, the conveyor, as well as the magazines and the package containers carried therein (although these machine components can be seen in Figure 3

[0044] Conveyors of this type comprising magazines are well known in the art and will not be further described here.

[0045] As can be seen in Figure 2 The sterilization station 100 is provided with a plurality of baffles 132. Two vertical baffles 132 are provided at the inlet side of the sterilization unit 100, extending from the bottom of the tunnel to the upper part of the tunnel. The baffles 132 are spaced apart in the machine direction, and the space formed between these baffles 132 serves as an inlet section 134 of the sterilization station 100.

[0046] Downstream of the inlet section 134, a supply section 110 is arranged. The purpose of the supply section 110 is to provide a flow of gaseous sterilant, preferably H2O2, so as to sterilize the interior as well as the exterior of the packages to be filled. As mentioned in the background section above, the dew point of the H2O2 gas ensures that H2O2 condenses on the inner surfaces of the packages to be filled.

[0047] The sterilization station 100, in particular the supply section 110, is preferably provided as a continuous tunnel in which, in the aerated portion at the vertical upper part, an atmosphere of gaseous sterilant of high concentration and relatively uniform is created in order to create a controlled and uniform distribution of the gas into the packages to obtain the required sterilization effect. This is achieved without causing a substantial condensation on the conveyor at the vertical lower part, as explained below.

[0048] Vertical baffles 136 are provided at the upper part of the supply section 110. The baffles 136 of the supply section 110 extend upwards from horizontally arranged baffles 138. The horizontal baffles 138 are spaced apart so that the magazines and the packages to be filled can pass between the horizontal baffles 138.

[0049] ​The vertical baffle 136 of the supply section 110 divides the space within the channel into four different indexing positions. In a preferred embodiment, each indexing position is associated with a gas supply pipe 140, preferably arranged at the longitudinal position of the vertical baffle 136. Thus, four packages to be filled can be positioned in the indexing positions at the same time, whereby the gas supply pipes 140 are activated to supply the gas sterilant towards the interior of the packages to be filled. In some embodiments, however, one or more gas supply pipes 140 can be replaced by, for example, a gas station, meaning that these positions are void of gas supply. In order to reduce the amount of sterilant on the conveyor, distribution pipes 150 are provided. Reference will be made to Figure 3 These distribution pipes 150 are further described.

[0050] Referring again to Figure 2 immediately downstream of the indexing positions is a holding section 112; here, the condensation is allowed to accumulate for a certain amount of time.

[0051] In another embodiment, H2O2 is used as sterilant, in combination with UV light sources arranged at the downstream holding section 112. The initial gas concentration can in this variant be much lower, for example 3% H2O2 compared to 35% H2O2, but since the dew point of the gas is much higher, the amount of condensation will increase significantly compared to the case of 35% H2O2.

[0052] Downstream of the holding section 112 is arranged a discharge station 120, the purpose of which is to evaporate all sterilant from the packages to be filled.

[0053] Turning now to Figure 3 a cross-section of the supply section 110 is shown. The packages to be filled 4 are carried by a magazine 5, which extends almost along the entire vertical extension of the packages to be filled 4. The magazine 5 in turn is driven by a conveyor (not shown) which is connected to the bottom of the magazine 5.

[0054] The gas supply pipes 140 are directed downwards, whereby sterilant is allowed to enter the packages to be filled 4 so that the interior is sterilized. An amount of sterilant will also condense on the outer surface of the packages 4 as well as on the magazine. The distribution pipes 150 arranged on each side of the magazine 5 and extending in horizontal direction, i.e. in the direction of the flow of the packages through the filling machine, help to reduce the amount of sterilant on the magazine 5 and on the conveyor. The distribution pipes 150 form a clean air supply which extends horizontally at a vertical position below the open end of the package container and is configured to direct a flow of clean air, preferably filtered and / or sterile air, towards the package container.

[0055] The idea is to introduce two distribution pipes 150 for cleaning air supply, one on each side of the conveyor / cassette 5 extending in horizontal direction and placed slightly below the horizontal baffle 138 in vertical direction, i.e. in a direction orthogonal to the flow of packages through the filling machine. These distribution pipes 150 are designed with a row of outlet holes 152 (see Figure 4 ). The distance between the distribution pipe 150 and the associated baffle 138 arranged vertically above the distribution pipe 150 is in the range of 2-100 mm.

[0056] The distribution pipes 150 extend along indexed positions so that four cassettes 5 can be exposed to cleaning air simultaneously.

[0057] Further details of the distribution pipes 150 are shown in Figure 4 . Typical dimensions of the outlet holes 152 can include a diameter of 4 mm and a centre-to-centre distance of 12 mm, although other dimensions can also be considered.

[0058] The outlet holes 152 are placed at an angle to the horizontal baffle 138 (see Figure 3 ), which will create a planar jet towards the conveyor and the outer surface of the package in the direction of package movement, as indicated by the arrows in Figure 3 . This planar jet of cleaning air will reduce the concentration of sterilizing agent, such as H2O2, in the vicinity of the conveyor and the outer surface of the package to be filled, without affecting the uniform and high concentration of gas above the horizontal baffle 138.

[0059] The introduced air flow can be very small, since the inlet air jet will entrain air from the lower part of the channel of the supply section 110, thereby further enhancing the gas dilution effect. This also means that the velocity of the resulting planar air jet will be very small, so that a high and controlled concentration can be maintained in the upper part of the supply section 110.

[0060] The supply of cleaning air to the distribution pipes 150 can preferably be integrated with the air supply system of the ventilation device 122. If branching is made after the heater connected to the air supply system, two benefits are obtained. First, since the cleaning air is relatively warm, it will also contribute to heating the horizontal baffle 138 and further enhance the evaporation of the condensation film on the cassettes 5 and the outer surface of the package containers 4. This will contribute to increasing the robustness of the system, also maintaining hygienic conditions within the piping system.

[0061] Turning now to Figure 5The diagram schematically illustrates a method 200 for sterilizing a package 4 to be filled. Method 200 includes a first step 202 of supplying a gaseous sterilizing agent toward the interior of the package 4 to be filled, and a second step 204 of providing a stream of clean air toward the outer surface of the package 4 to be filled. Preferably, step 204 of providing a stream of clean air toward the outer surface of the package 4 to be filled includes directing a plurality of clean air jets toward a baffle 138 to provide a planar stream of clean air.

[0062] Turn now Figures 6a to 6c The diagram illustrates a filling machine 10 during a simulated process, where a gaseous sterilizing agent (in this case, H2O2) is supplied toward the open ends of a series of packages 4 to be filled. Each package 4 is carried by a cartridge 5 as described above. Figure 6a As can be seen, sterilization occurs at four graduation points.

[0063] Figure 6a This shows that the sterilizing agent is concentrated inside the package to be filled 4, in contrast, in Figure 6c In the simulation, the sterilizing agent leaked and distributed around the package to be filled 4. Figure 6a The filling machine 10 and Figure 6c The difference between the filling machines is that, Figure 6a One type of clean air supply is in the form of two distribution pipes 150 that provide a jet of clean air toward the package to be filled 4.

[0064] exist Figure 6b middle, Figure 6a The filling machine 10 is shown in cross-section, further illustrating the function of the dispensing tube 150.

[0065] As can be seen from the above description, although various embodiments of the invention have been described and illustrated, the invention is not limited thereto, but may be implemented in other ways within the scope of the subject matter defined by the appended claims.

Claims

1. A filling machine (10) configured to form, fill, and seal individual packaging containers, the filling machine (10) comprising a sterilization station (100) configured to provide a gaseous sterilizing agent flow toward an open end of a packaging container (4) to be filled passing through the sterilization station (100), Its features are, The filling machine further includes at least one clean air supply, wherein the air supply is configured to direct a stream of clean air toward the packaging container (4) to be filled. The packaging container (4) to be filled is conveyed by a conveyor comprising a plurality of consecutive cassettes (5), wherein the cassettes (5) carry the packaging container (4) to be filled. The clean air supply includes at least one distribution pipe (150) extending in a horizontal direction, the direction in which the packaging flow passes through the filling machine (10), and the distribution pipe (150) being provided with a plurality of outlet holes (152) distributed along the longitudinal direction of the distribution pipe (150). The filling machine includes baffles (138) arranged above the at least one clean air supply, wherein the baffles (138) are spaced apart such that the cassette (5) and the packaging container (4) to be filled can pass between the baffles (138).

2. The filling machine according to claim 1, wherein the outlet hole (152) points upward and inward toward the packaging container (4) to be filled.

3. The filling machine according to claim 1 or 2, comprising a first dispensing tube disposed on one side of the packaging container (4) to be filled, and a second dispensing tube disposed on the opposite side of the packaging container (4) to be filled.

4. The filling machine according to claim 1 or 2, wherein the clean air supply is configured to provide a planar jet of clean air toward the packaging container (4) to be filled.

5. The filling machine according to claim 1 or 2, comprising multiple indexing positions for supplying a gaseous sterilizing agent to a plurality of packaging containers (4) to be filled, wherein the clean air supply in the form of one or more distribution tubes (150) extends through the indexing positions.

6. The filling machine according to claim 1 or 2, wherein the clean air supply is connected to an air supply system for a downstream ventilation device (122).

7. A method for sterilizing a packaging container (4) to be filled, the method comprising supplying (202) a gaseous sterilizing agent toward the interior of the packaging container (4) to be filled, and providing (204) a clean air stream toward the outer surface of the packaging container (4) to be filled, wherein providing (204) the clean air stream toward the outer surface of the packaging container (4) to be filled comprises directing a plurality of clean air jets toward a baffle (138) to provide planar jets of clean air; in, The baffle (138) is arranged above at least one clean air supply, wherein the air supply is configured to direct the clean air flow toward the packaging container (4) to be filled; wherein the packaging container (4) to be filled is conveyed by a conveyor comprising a plurality of consecutive cartridges (5), wherein the cartridges (5) carry the packaging container (4) to be filled, wherein the baffles (138) are spaced apart such that the cartridges (5) and the packaging container (4) to be filled can pass between the baffles (138).

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