RU2430002C2 - Method to sterilise packages - Google Patents

Abstract

FIELD: packing industry.

SUBSTANCE: method includes stages of dividing at least the inner surface of a package into at least two areas, which are to be sterilised. Two of at least two areas are sterilised by arrangement of an electronic beam sterilisation for each of two areas. Sterilisation devices are adapted to characteristics of every area. At the same time relative displacement is provided between the package and each of two electronic beam sterilisation devices. Then the package is transported to a station to fill the package with a product via an opening, and the package is sealed.

EFFECT: provision of even sterilisation of the package on its every part.

10 cl, 24 dwg

Description

The present invention relates to a method for sterilizing at least partially formed packages in a packaging machine.

State of the art

The food packaging industry has long used packaging formed from blanks of packaging material, a material made up of different layers of paper or cardboard, liquid barriers, such as polymers, and gas barriers, such as thin films of aluminum. The preforms are preformed from a web of material, which is sometimes provided with a pattern of fold lines that facilitate the formation and folding of packages. The canvas is cut into pieces, each piece has a size and shape to create a package. After cutting, each piece is bent into a blank having the shape of a flat pipe, having its longitudinal edges overlapping with each other. The longitudinal edges are then sealed by any suitable conventional technology, for example, such as heat sealing. The result is a flat-shaped blank. The formation of the blank from the web is essentially well known and will not be described in more detail.

In a packaging machine, a preform is molded to form a pipe, typically having a square or rectangular cross section, depending on the type of packaging. After that, one end of the pipe can be sealed transversely, forming the bottom (or top) of the package, and the package is ready for filling with a product, such as food products, such as, for example, drinks. These packaging options are marketed by the applicant under the brand name Tetra Rex®.

There are also cardboard bottle packaging made from a tube-shaped sleeve of packaging material, as described above, and a plastic cap sealed to the sleeve. The covers are either prefabricated outside the packaging machine or are injection molded directly onto the sleeve in the packaging machine. The covers are equipped with closures. These types of packages can be filled before the lower end of the liner is transversely sealed and finally folded into the bottom. They can also be filled through the filling opening of the capping part. Packages like these are marketed by the applicant under the brand names Tetra Aptiva® and Tetra Top®.

Partially formed packages that are open at one end for filling but sealed to form a bottom or top at the other are usually indicated as ready-to-fill packages (RTF packages). Subsequently, packages ready for filling will be indicated by the wording “packaging”.

In order to extend the shelf life of packaged products, it is known in advance that packages should be sterilized before the filling operation. Depending on how long a shelf life is required, and whether distribution and storage is performed at a chilled or ambient temperature, different sterilization levels can be selected. However, the form of the expression "sterilize" here is inclusive of any level of purification and microbiological suppression.

One method of sterilization is to irradiate the inside of a package with electrons emitted from an electron beam unit. Such a method and apparatus for implementing the method are disclosed by the applicant in the international patent publication WO 2005/002973, which is hereby incorporated by reference.

An exemplary system for sterilizing packages by electron beam technology includes an electron beam sterilization device for emitting an electron beam along a path. The device is connected to an electron beam generator, which is connected to a high voltage power source and a glow voltage source. The latter converts power from a high voltage power source to a suitable input voltage for the generator filament. The filament may be placed in a vacuum chamber. In action, electrons e from the filament are emitted along the path of the electron beam in the direction of the target. The grid around the filament is used to scatter the electron beam into a more uniform beam and to focus the electron beam in the direction of the target. Beam absorbers and magnetic fields can also be used to shape an electron beam. Electrons exit the sterilization device through the electron exit window.

However, when sterilizing the packages, it was found that it is difficult to achieve a uniform dose of the electron beam throughout the entire package taken with a single electron beam sterilization device. This is due to different forms of the physical parts of the package. Corners, openings, corking parts, bottle-shaped tops, bottoms, flat walls, etc. it must be sterilized sufficiently, but preferably without excessive exposure. This is also a cost issue. It is preferable not to be forced to use more energy than necessary.

Disclosure of invention

Therefore, the aim of the invention was to provide a method for sterilizing at least partially formed packages by irradiating an electron beam in a packaging machine, with which it is possible to obtain a substantially uniform dose on all parts of the package, that is, to achieve a predetermined level of sterilization , all parts of the package must be subjected to a predetermined dose of the electron beam.

The goal was achieved using a method containing the steps of: dividing at least the inner surface of the package into at least two areas that must be sterilized, sterilizing two of the at least two areas by providing an electron beam sterilization device for each of the two regions, the sterilization devices mentioned are adapted to the characteristics of each respective one of the two regions, as well as ensuring the corresponding relative movement between the packaging and each m of two electron beam sterilization devices, which movements are adapted to sterilize each respective one of the two areas with the help of the aforementioned sterilization devices, and transport the package to the filling point to fill the package with the product through the opening, and then seal the package.

In this way, one suitable sterilization device may be selected for each area to be sterilized. In other words, sterilization can be optimized for the reason that the configuration of each sterilization device can be adapted to characteristics, such as shape, size, etc., of the corresponding area. In addition to adapting the configuration of the sterilization device, the relative movement between the package and the sterilization device can also be adapted. Even if the sterilization device is adapted to a specific area, some areas may need a longer exposure time or a slower electron beam movement than others to sterilize sufficiently. By combining an adapted sterilization device with an adapted relative displacement, package sterilization can be very efficient in terms of energy and time consumption. The combination also makes it possible to achieve an economical sterilization system.

In a currently preferred embodiment of the invention, the method further comprises the step of sterilizing additional regions by providing an electron beam sterilization device for each of the regions, said sterilization devices being adapted to the characteristics of each respective one of the regions. The packaging can be divided into any number of areas, and the packaging machine can be equipped with an appropriate number of sterilization devices. In this way, very careful irradiation of the package can be performed.

In yet another embodiment of the invention, the method comprises the step of dividing at least the inner surface of the package so that the formed regions are at least partially overlapping. By doing this, it can be guaranteed that at least no part of the inside of the package remains unsterilized. In some cases, the area may be more or less completely overlapping another.

An additional embodiment comprises a preparation step for sterilizing an area, a sterilization device coupled to an electron beam generator. An electron beam generator can be placed in a sterilization device to form a compact unit that is easy to move and handle.

Yet another embodiment includes a preparation step for sterilizing areas, sterilization devices, some of which are coupled to the same electron beam generator. If applicable, a number of sterilization devices may be coupled to the same electron beam generator. This saves space and can be more economical than having one electron beam generator per sterilization device.

In a further embodiment, the method comprises a preparation step for sterilizing areas, sterilization devices, all of which are coupled to the same electron beam generator.

In a further embodiment, the method comprises the step of sterilizing the regions by sterilizing devices, each provided with at least one electron exit window to exit at least a portion of the electron beam formed by the at least one electron beam generator. The electron beam exit window is used to exit the electrons and is an important parameter for adapting the sterilization device to the area. Different window configurations give different exposure characteristics.

In yet another embodiment, the method comprises the steps of: preparing at least a first and a second treatment point in a sterilization chamber, each is arranged with at least one electron beam sterilization device, placing the package in the first paragraph and sterilizing, at least the first region of the interior of said package using an electron beam sterilization device in said first paragraph and placing the package in the second paragraph and sterilizing at least the second region interior of said package by means of electron beam sterilization apparatus in said second step.

An embodiment comprises additional steps of placing the package in at least one additional item, said item being arranged in a sterilization chamber and provided with at least one electron beam sterilization and sterilization device for at least a region containing part of the outside packing near her opening. In this way, re-contamination from the outside of the package and into the package can be prevented.

An additional embodiment further comprises the step of sterilizing more than one package at each point. In this way, the productivity of the packaging machine can be increased.

Brief Description of the Drawings

In the following, the currently preferred embodiment of the invention will be described in more detail with reference to the accompanying drawings, in which the same reference numbers were used to denote identical elements, on which:

FIG. 1 schematically shows two partially formed packages to be sterilized according to the method of the invention,

FIG. 2 schematically shows an example system for executing a method,

FIG. 3 schematically shows a view of a number of sterilization devices connected to a common electron beam generator,

FIG. 4 schematically shows a view, partially in cross section, of a sterilization chamber comprising three treatment points, each equipped with one sterilization device and a filling chamber,

FIG. 5 schematically shows a view similar to that of FIG. 4, but with two sterilization devices at each treatment point, and

FIG. 6a-f schematically show different embodiments of sterilization devices. Each sterilization device is shown in the outside view, partially in cross-sectional view, and axial end view provided with an exit window configuration.

For simplicity, such features in different embodiments will be denoted by the same reference numbers.

The implementation of the invention

FIG. 1 shows two embodiments of partially molded packages, indicated by reference number 10, which are to be sterilized by the method of the invention. As mentioned in the introduction, partially formed packages are usually closed at one end 12 and have an opening 14 at the other end. The closed end 12 may be formed as a bottom or top, and the opening 14 may be the open end of the packaging sleeve, which may later be sealed, or, for example, a bulk opening surrounded by a neck of a closure, which may later be provided with a lid or the like. An embodiment of packaging on the right in the figure has a sealed lower end and an opening in the upper part in the form of a filling opening surrounded by a threaded neck of a closure. An embodiment of packaging on the left has an open (lower) end and is provided with an upper and a sealed closure on the other end.

Subsequently and with reference to FIG. 2, an electron beam generator 16, an electron beam sterilization device 18, and an electron beam sterilization concept will be briefly described. The electron beam generator 16 comprises means for emitting an electron beam 20 along the path and is connected to a sterilization device that extends the beam 20 to the package 10.

Typically, an electron beam generator 16 is connected to a high voltage power supply 22 suitable for supplying sufficient voltage to drive an electron beam generator 16 for a desired application. An electron beam generator 16 is also coupled to a glow voltage source 24, which converts the power from the high voltage power source 22 to a suitable input voltage for the filament 26 of the generator 16. In addition, the high voltage power source 22 includes a grid control 28 to control the grid 30 generator 16 electron beam.

Electron beam generators used to sterilize packages are usually referred to as low-voltage electron beam units, which units typically have voltages below 300 kV. In the disclosed structure, the accelerating voltage reaches about 70-90 kV. This voltage results in kinetic (motor) energy of 70-90 kiloelectron-volts in relation to each electron.

The filament 26 can be made of tungsten and can be placed in the vacuum chamber 32. In an exemplary embodiment, the vacuum chamber can be sealed. During operation, an electric current is supplied through the filament 26, and the electrical resistance of the filament makes the filament heat up to a temperature of about 2000 ° C. This heating causes the filament 26 to emit a cloud of electrons e. Electrons are emitted along the path of the electron beam towards the target region, in this case, the region on the package 10. The grid 30, placed between the filament and the exit window of the electron beam, is equipped with a number of openings and is used to scatter the electron beam 20 into a more uniform beam and for focusing a beam of 20 electrons on the target region.

In the shown embodiment, the means of the electron beam generator is located in the device 18 electron beam sterilization. The sterilization device 18 comprises a vacuum chamber, which in this case is the same vacuum chamber as the vacuum chamber 32 of the electron beam generator 16. The sterilization device 18 is further provided with an electron exit window 34. The window 34 may be made of a metal foil, for example, such as titanium, and may have a thickness of about 4-12 microns. A reinforcing mesh formed of aluminum or copper supports the foil from within the electron beam generator 16. Electrons exit the vacuum chamber 32 through the exit window 34.

In this embodiment, the sterilization device 18 with the electron beam generator 16 inside has a cylinder shape with a substantially circular cross section, and the exit window 34 is located at the first end of the cylinder.

In another embodiment shown in FIG. 3, the electron beam generator 16 and the sterilization device 18 are, of course, connected, but only the sterilization device 18 interacts with the package 10, that is, the sterilization device 18 is at least partially located or moves either inside or around the package 10 during irradiation . Vacuum chambers (not shown externally) are then in communication with each other, and the sterilization device 18 functions as an extension cord or nozzles of the electron beam generator 16, that is, is used to reach the parts of the package that must be sterilized.

A support (not shown) is provided to support the target, i.e., the package 10 within the region of the target. The support, for example, may be a conventional conveyor conveyor, which conveys the package 10 through a sterilization chamber. During sterilization of the package 10, similar to that on the left of FIG. 1, the package 10 can be placed upside down (i.e., the top is installed downward) on a support.

In addition, during sterilization, relative movement is performed between the package 10 and the sterilization device 18. The sterilization device 18 is lowered in or near the package 10 or the package 10 is raised to surround the device 18, or each is moving towards each other. To achieve such a support can be fixed or adapted to perform movement to and from the sterilization device 18.

At the second end of the sterilization device 18, comprising an electron beam generator 16, there is a means (not shown) provided for attaching it to a preferred element in the environment. For example, such a tool may be a means for mixing the sterilization device or the electron beam generator from the inner upper wall of the sterilization chamber with the electron beam exit window 34 facing down towards the package 10. Alternatively, the second end face is equipped with means (not shown) for providing relative movement (see arrow) between the package 10 and the sterilization device 18 to bring them into position or in motion in which said device 18 is located at least frequently chno in or around the package 10 for treating it.

Relative movement can be done in many different ways. For example, it may comprise slowly lowering the sterilization device into the package, followed by a short stop and a quick rise from the package. Alternatively, the relative movement may include lowering and rising without any stop. In an additional alternative embodiment, lowering and lifting are very fast, but with some short stops during the journey.

FIG. 4 shows a sterilization chamber 36 through which packages 10 are transported in the direction of the horizontal arrow to sterilize. In order to extend the shelf life of packaged products, it is known in advance that packages should be sterilized before the filling operation. Depending on how long a shelf life is required, and whether distribution and storage is carried out at a chilled or ambient temperature, different sterilization levels can be selected. For ambient temperature, sterilization to a level that is indicated as being sterile commercially is preferred. However, the form of the expression "sterilize" here is inclusive of any level of purification and microbiological suppression.

The figure also shows a filling chamber 38. The packages 10 are transported to the filling chamber 38 after they have been sterilized in the sterilization chamber 36. The filling chamber 38 is provided with at least one filling point 40 for filling the packages 10 with the product through their opening. As mentioned previously, the opening may be either the still open end of the package or part of an unsealed closure, such as, for example, a filler opening surrounded by a neck.

Said filling point 40 may be part of any suitable type of packaging filling system. For example, a linear filling system or a rotary filling system may be used. The filling system will not be described in more detail.

The sterilization method according to the invention comprises the step of dividing at least the inner surface of the package 10 into at least two regions that must be sterilized. Each of the areas is sterilized by a respective electron beam sterilization device 18. By using a number of sterilization devices 18 and treating the package 10 of a certain area at a time, each sterilization device 18 can adapt to characteristics, such as the shape and size, of the area that it will be sterilized. This means that each device 18 can be significantly optimized for the area that it will irradiate, that is, it will be able to produce an electron beam 20 or part of it on a trajectory suitable for the specific area to be sterilized. For this purpose, the sterilization chamber 36 is provided with at least two electron beam sterilization devices 18 for at least two areas.

The area here is defined as the surface of the package to which the sterilization device is adapted. Dividing into regions can be done in any convenient way. For example, the region may be in the form of a lower portion of a package. Another area may be in the form of part of the inner surface of the packaging shell. Another other area may be in the form of a closure or top of the package. However, the division is not necessarily limited to the physical parts of the package. For example, the area may be composed of a portion of the bottom and a portion of the lower end of the inner surface of the shell. Another area, for example, may be composed of a closure and the top of the package. Another area, for example, may be composed of a closure and the top of the package. The parts and surfaces of the package, included in one area, do not need to be continuous or connected, they can be completely separate from each other. The required number of different sterilization devices is dependent on the number of different areas present in the package.

The regions can at least slightly overlap each other to ensure that no part of the package is endowed with too low an electron beam dose. In some cases, the area may be more or less completely overlapping another. A sterilization device adapted to sterilize an area of the top of a package will be described later. However, it may be necessary for the dose to be increased over the area of the closure in the upper part by another sterilization device in order to be effectively sterilized. The second region in this case will be completely overlapping the first.

Each sterilization device 18 is configured to optimally irradiate the designated area that it will irradiate. The features of the sterilization device 18, which can be modified to achieve different radiation characteristics required for different areas, for example, are the shape and dimensions of the sterilization device 18, as well as the number of electron beam exit windows 34 and their placement and shape. For additional changes in the characteristics of the electron beam 20, the filament 26 and the control grid 30 can be modified.

In addition, the relative movement between the package 10 and the sterilization device 18, which is schematically shown by the vertically arranged arrows in FIG. 4 is configured for optimal exposure with sterilization device 18.

In the exemplary embodiment described in FIG. 4, the sterilization chamber 36 is equipped with the first and second processing points I, II. It will be described later that an additional, in this case, third point III is also provided in the sterilization chamber 36.

The first point I is the point at which the first packing area 10 should be sterilized, and the second paragraph is the point at which the second packing area 10 should be sterilized. Each of the mentioned points I, II contains one electron beam sterilization device 18 for sterilization of the respective areas.

Sterilization devices 18 in paragraphs of FIG. 4, both can be separate sterilization devices, each of which is attached to its own electron beam generator. The electron beam generator 16 in this case can be placed in the vacuum chamber 32 of the sterilization device 18. Alternatively, sterilization devices 18 are connected to a common electron beam generator 16, as shown in FIG. 3. However, for clarity, it should be noted that the items in FIG. 3 are shown as being equipped with sterilization devices other than those shown in FIG. four.

In the embodiment of FIG. 4, the first paragraph I is used to sterilize the area containing the wrong side of the upper part and the wrong side of the closed closure. The second paragraph II is used to sterilize the area in the form of the inner surface of the packaging shell.

The sterilization device 18 in the first paragraph I will be described later in more detail with reference to FIG. 6a. It contains a flat exit window to create a wide circular beam, suitably used to irradiate the area, for example, in the form of a domed top of the package. The sterilization device 18 in the second paragraph II, which will be described later with reference to FIG. 6d is equipped with a plurality of electron beam exit windows arranged to create an electron beam suitably used, for example, for irradiating, the circular surface of the package shell 10.

As mentioned previously, the sterilization chamber 36 also comprises an additional third point III for sterilizing at least a portion of the outer side of the package 10 near its opening before filling the package 10. Such a sterilization device 18 will be described later in more detail with reference to FIG. 6f.

The package 10, with its top pointing downward, enters the sterilization chamber 36 on the left in FIG. 4 and transported to the first processing point I. In the first processing point I, the first sterilization device 18 is lowered a suitable distance into the package 10 from the upper position shown and irradiates the first area of the package 10. The area is irradiated for a predetermined time, which time depends on the relative movement between the package 10 and the sterilization device 18. After a predetermined time, the sterilization device 18 rises again, and the package 10 is transported to the second processing point II, where the second region is irradiated with the sterilization device 18 in the said paragraph II. The sterilization device 18 is lowered and raised in a similar manner. The relative displacement and, therefore, the exposure time may be similar or different than in the first paragraph.

After the second processing point II, the package is transported to the third paragraph III, in which a region in the form of at least part of the outer side of the package 10 near its open end is sterilized to prevent re-contamination of the inside of the package. Similarly, the sterilization device 18 is lowered near the open end 12 of the package 10 and is sterilized for a predetermined time. The sterilization device 18 is then lifted, and the sterilization of the package 10 is completed. The package 10 is then ready to move into the next chamber, the filling chamber 38, in order to be filled. After filling, the package 10 is sealed. In this case, the package 10 is sealed for the reason that the open end 12 of the package sleeve is compressed and transversely sealed by heating in a conventional manner.

In an alternative embodiment where the package is sterilized and filled through the filling opening at the top of the package, see the package on the right in FIG. 1, the sealing procedure comprises supplying a neck, a surrounding filler opening, a membrane and / or a cap, such as, for example, a screw cap.

FIG. 5 shows a second embodiment of a sterilization chamber 36 in FIG. 4. In this second embodiment, treatment points are provided, each of which comprises more than one electron beam sterilization device 18 of the same kind. In this way, more than one package can be sterilized at some point in time at each point. Preferably, the sterilization devices 18 may be coupled to a common electron beam generator similar to that shown in FIG. 3. The packaging machine must double-index the packages, that is, the package 10, being in the first sterilization device 18 in the first paragraph I, is transported directly to the first sterilization device 18 in the second paragraph II.

In the following, a number of sterilization devices 18 will be described having different characteristics of the electron beam, for example, due to different shapes and configurations of windows.

The first sterilization device 18 shown in FIG. 6a has a cylindrical rounded body 42 of a size corresponding to the size of a package having a circular cross section. A cylindrical housing 42 surrounds the electron beam generator 44, and the filament and the generator grid are shown schematically in the figure. An electron beam exit window 46 is provided on one axial end of the cylindrical body. In this embodiment, the window 46 is flat, round and has a size substantially corresponding to the round end of the housing 42. The filament may be in the form of a ring or in a straight line. The grid is adapted to scatter the electron beam 20 into a more uniform beam and to focus the electron beam 20 on the exit window 46 in some way to cause the electron beam to exit the window essentially through its entire surface or through selected portions thereof. This configuration is suitably used, for example, to irradiate the area in the form of a flat bottom of the package. The sterilization device 18 is then lowered into the package from the open top end of the package or the package is lifted to surround the sterilization device. Alternatively, this sterilization device 18 may be used to irradiate a circle-shaped area on top of a symmetrical or domed package. The sterilization device 18 is then lowered into the package from the open bottom end of the package or the package is lifted to surround the sterilization device 18. Alternatively, the region is formed by the bottom and the inner surface of the packaging shell. Relative movement in this case may include a slow lowering of the sterilization device and a short stop near the bottom of the package.

The second sterilization device 18 shown in FIG. 6b is substantially similar to the first, but the housing 42 is provided with a narrow rounded nozzle 50. An electron beam exit window 46 is located at one of the axial ends and is flat and round. The sterilization device 18 can be used to irradiate packages, such as bottles with a narrow open end, through which the sterilization device must be lowered and raised. A configuration such as this is also used to amplify the electron beam 20 in a specific area, such as in a small area, such as openings or closures and other irregularities. It should be clear that the shape of the nozzle may be different than round, for example, it may be in the form of a square, rectangle, triangle, oval or have any other shape.

The third sterilization device 18 shown in FIG. 6c is also substantially similar to the first sterilization device in its basic design, but provided with a plurality of exit windows 46 arranged in a cone-shaped configuration to create a wide circular beam 20 with a reinforced dose in the direction of each window 46. If four windows 46 are arranged, like shown, the sterilization device 18 is used appropriately to irradiate a symmetrical square package with corners. To ensure a uniform dose inside the package, the windows are preferably arranged to face the corners. This configuration is also suitable for irradiating the rounded inner surface of the shell. Compared to the configuration in the first sterilization device, this configuration will be faster during sterilization of the shell surface of cylindrical packages, since the average electron path length is shorter.

The fourth sterilization device 18 shown in FIG. 6d, is substantially similar to the previous one and is also provided with numerous windows 46. Windows 46 are arranged on the shell surface of a cylindrical rounded body 42. A window 46 may also be provided at the end of the body. The created electron beam 20 propagates both downward and sideways, and the sterilization device 18 is suitably used to irradiate an area containing both the substantially flat bottom of the package and the inner surface of the package shell.

The fifth sterilization device 18 shown in FIG. 6e is substantially similar to the first, but provided with an axial, square-shaped, flat electron beam exit window 46. The size of the window 46 is larger than the cross-section of the round body 42. Therefore, the end face made with the window 46 is provided with a flange 52. The end face of the flange 52 connected to the round body 42 is round, and the end face provided with the window 46 is square. The grid is adapted to focus the electron beam 20 on the exit window 46 in some way to cause the electron beam 20 to exit the window 46 essentially through its full surface or selected portions thereof. This configuration is suitably used to irradiate the area in the form of a square-shaped bottom of the package or a square-shaped inner surface of the package. Alternatively, the window 46 has a different shape, such as elliptical or cruciform, for irradiation with appropriate shaped packages.

The sixth sterilization device 18 shown in FIG. 6f is essentially similar to the previous devices, but it differs in that it can be used properly for irradiating non-planar forms. A funnel-shaped portion 54 is provided at the end of the rounded housing 42. The width of the funnel-shaped portion 54 increases in the direction from the housing 42. Numerous electron exit windows 46 are arranged inside the funnel-shaped portion 54 of the conical shape 56. The conical shape 56 narrows toward the housing 42. Thus, the exit windows 46 can move close to the surface of the package, even if the surface is convex or provided with a protruding closure. Preferably, the area on the outside of the bottle-shaped top of the package can be irradiated with this device. In addition, covers may also be irradiated.

In the method of the invention, for example, at least the first and second sterilization devices can be used to sterilize a package similar to the one on the left in FIG. 1. The first sterilization device is a sterilizing area containing the surface of the shell and the surface of the upper part, while the second sterilization device gives additional reinforcement in relation to the area in the form of a back of the closure. A sixth sterilization device may be added to sterilize an area containing a portion of the outer surface of the package near the opening 14. Relative movement is adapted to each area.

Although the present invention has been described with respect to the currently preferred embodiments, it will be understood that various modifications and changes can be made without departing from the subject and scope of the invention as defined in the appended claims.

In a further embodiment, the two processing points are combined. For example, the first and second paragraphs are provided in the same place for sterilizing the package, first using the electron beam sterilization device of the first paragraph, and then sterilizing the package with the electron beam sterilization device of the second paragraph. The package is not transported anywhere between doses of radiation, but sterilization devices are either replaced once or twice during stopping the package, or served together. In the example of FIG. 4 instead, for example, two sterilization devices may be provided in the first paragraph, in reality, forming two paragraphs. The first sterilization device can be adapted to sterilize the area in the form of a back of the closure, and the second sterilization device can be adapted to sterilize the area in the form of an upper part, that is, the area around the closure. Similarly, for example, a second paragraph and an additional third paragraph may be combined. Sterilization devices in this case, for example, can be arranged one around the other.

In addition, the packages have been described as having an inner surface of the shell, and the figures show that the packages have a circular cross section. However, it should be understood that the form of expression of the inner surface of the package shell should be interpreted as the inner wall or walls of the package, regardless of the cross section of the package. The cross section of the package can have almost any shape, such as a round, square, rectangular, oval, triangular, orthogonal or other shape.

Claims (10)

1. The method of sterilization of at least partially formed packages (10) by irradiation with an electron beam in a packaging machine, characterized in that it contains stages in which:
divide at least the inner surface of the package (10) into at least two areas that must be sterilized,
sterilizing two of the at least two regions by providing an electron beam sterilization device (18) for each of the two regions, said sterilization devices (18) being adapted to the characteristics of each of the respective one of the two regions, and also that provide relative relative movement between the package (10) and each of the two electron beam sterilization devices (18), these movements are adapted to sterilize each respective one of two areas using said sterilization devices (18), and
transport the package (10) to the filling point (40) to fill the package (10) with the product through the opening (14), and then seal the package (10). 2. The method according to claim 1, in which it comprises the step of sterilizing additional areas by providing an electron beam sterilization device (18) for each of the areas, said sterilization devices (18) being adapted to the characteristics of each respective one from areas. 3. The method according to claim 1, in which it comprises the step of dividing at least the inner surface of the package (10) so that the formed regions at least slightly overlap each other. 4. The method according to any one of claims 1 to 3, in which it comprises the step of sterilizing the device with a sterilization device (18) connected to an electron beam generator (16). 5. The method according to any one of claims 1 to 3, in which it comprises the step of sterilizing devices (18) for sterilizing the regions, some of which are connected to the same electron beam generator (16). 6. The method according to any one of claims 1 to 3, in which it comprises the step of sterilizing devices (18) for sterilizing the regions, all of which are connected to the same electron beam generator (16). 7. The method according to any one of claims 1 to 3, in which the areas are sterilized by sterilization devices (18), each equipped with at least one electron exit window (46) to exit at least a portion of the electron beam (20) formed by at least one electron beam generator (16). 8. The method according to claim 1, in which it further comprises stages in which:
provide at least the first and second treatment item (I, II) in the sterilization chamber (36), each is made with at least one electron beam sterilization device (18),
place the package (10) in the first paragraph (I) and sterilize at least the first interior region of said package (10) using the electron beam sterilization device (18) in said first paragraph (I) and
place the package (10) in the second paragraph (II) and sterilize at least the second region of the inside of said package (10) using the electron beam sterilization device (18) in the said second paragraph (II). 9. The method according to claim 8, in which it contains additional steps, which place the package (10) in at least one additional paragraph (III), said paragraph (III) is arranged in a sterilization chamber (36) and provided, at least one electron beam sterilization device (18), and at least a region containing a portion of the outer side of the package (10) near its opening (14) is sterilized. 10. The method according to claim 8 or 9, in which it further comprises the step of sterilizing more than one package (10) in each paragraph.

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