Device for sterilising containers

p0001The present invention relates to an apparatus for sterilizing containers, specifically for sterilization of containers before their filling. Specifically intended by the apparatus according to the invention the inner wall of containers to be filled, particularly bottles having a mouth to be sterilized.

p0002When foods are filled in a container, it is necessary to sterilize the container itself. It is known, for example, to sterilize the inner wall of containers with steam or hydrogen peroxide. Such methods are, however, associated with disadvantages, since it for example with hydrogen peroxide can lead to a softening of the material through the treatment. Therefore, it has long been known from the prior art to sterilize the containers with the aid of charge carriers as in particular electron beams.

p0003From the <patcit id="pcit0001" dnum="JP2002255125A"><text>JP 2002-255125</text></patcit> discloses an apparatus for sterilizing containers. In this case, an opening provided outside of the container radiation source is provided the radiation is directed into the interior of the container. Also in the<patcit id="pcit0002" dnum="JP2001225814A"><text>JP 2001-225814</text></patcit> is a corresponding apparatus for inner wall sterilization of containers is described in which a radiation source of radiation radiates outside into the container.

p0004From the <patcit id="pcit0003" dnum="FR2815769"><text>FR 2815769</text></patcit> is an electron beam source known that emits two electron beams.

p0005The <patcit id="pcit0004" dnum="DE19882252T1"><text>DE 198 82 252 T1</text></patcit> describes a technique for internal sterilization of a container by means of electrons. In this case, an electron beam source is also provided which directs the radiation from outside into the interior of the container.

p0006These said devices have the disadvantage that the radiation always through the mouth of the container from entering from the outside into this and thus in the interior of the container is difficult to be varied with respect to their beam direction.

p0007From the <patcit id="pcit0005" dnum="EP0885142B1"><text>EP 885 142 B1 0</text></patcit> discloses a method for the sterilization of packages eluant. It is in particular to packagings with an open side. In this process, high acceleration voltages should be avoided, as are produced as an unwanted side effect of this high acceleration voltages X-rays and this would in turn be shielded with a lead sheath. In order to achieve both an interior cleaning effect, is in the<patcit id="pcit0006" dnum="EP0885142B1"><text>EP 885 142 B1 0</text></patcit> proposed to use a gas stream, which is in contact with an electron beam and in this way contributes to the electrons can reach the inner wall of the container. The in<patcit id="pcit0007" dnum="EP0885142B1"><text>EP 885 142 B1 0</text></patcit> however described method for cleaning the inside of bottles or generally containers with a mouth diameter unsuitable because in the <patcit id="pcit0008" dnum="EP0885142B1"><text>EP 885 142 B1 0</text></patcit> Electron-beam source described could not be passed through this orifice and at least not together with the in <patcit id="pcit0009" dnum="EP0885142B1"><text>EP 885 142 B1 0</text></patcit> described air pipe, which generates the air flow inside the container, could be introduced into this container.

p0008The present invention is therefore based on the object, an efficient apparatus and method for cleaning the inside of containers compared to the container cross-section closer orifice cross-section to provide.

p0009This is inventively achieved by a device according to claim 1, an arrangement according to claim 15 and a method according to claim 20th Advantageous embodiments and developments are subject matter of the dependent claims.

p0010The inventive device for sterilization of containers comprises a treatment head, which in turn comprises an exit window, can pass through which charge carriers. Furthermore, a carrier generation source is provided which generates charge carriers, and an acceleration means which accelerates the carriers in the direction of the exit window.

p0011According to the invention the cross-section of the treatment head is such that the treatment head can be guided by the mouth of the container and the accelerating device accelerates the carriers such that the emerging from the exit window carrier, preferably directly on an inner wall of the container are directable.

p0012When the charge carriers are electrons, in particular, but it is also conceivable that other carriers, such as ions, are used.

p0013In contrast to the cited prior art thus accelerating voltages are used, which are high enough that the emerging electron beam impinges directly on the inner wall of the container, without through the intermediary of a gas stream that is activated by the electron beam for a sterilizing effect. Under an exit window is understood to mean a device which, although the interior of the device, ie, the region between the charge carrier generating source and the exit window air-tight manner, by which, however, nevertheless the charge carriers can occur in particular through the electron It should be noted that the emerging from the exit window electrons are strongly decelerated, so that in contrast to that of the<patcit id="pcit0010" dnum="EP0885142B1"><text>EP 885 142 B1 0</text></patcit> known device significantly higher energies or accelerating voltages are used.

p0014In order to generate the electron beam preferably a compact electron beam unit is used with a beam finger, as mentioned above, dimensioned so that it can dip into the bottle in order to apply an electron cloud with the least possible energy to the inner surface of the (PET) bottles. In the case of a rotary assembly, it is possible that operating units of the apparatus, such as transformers or power supplies run along the electron gun on a carousel, thereby simultaneously simplifies the supply of high voltage. In a preferred embodiment, the exit window and the acceleration device are arranged within an outer casing and this outer casing is such that it can be guided by the mouth of the container. The treatment head is thus provided at the lower end of this outer housing or it is also possible that the treatment head to the outer casing is integrally formed. Preferably, therefore, the entire outer housing of the treatment head has a cross section which is insertable through the mouth of a container. The treatment head cross section may be of any desired shape. Particularly preferably, the device has a circular Quersch on Nitt with a diameter which is less than 40 mm, preferably less than 30 mm and most preferably below 25 mm.

p0015Preferably the entire apparatus is surrounded by a shielding device and in particular by a lead sheath to prevent the escape of X-rays and thus adverse effects on the user.

p0016In a further preferred embodiment, the apparatus comprises an inner housing within which the acceleration means is arranged and the outer housing surrounds this inner housing. The interior of this inner casing, in which the charge carrier generating source and the acceleration device are preferably provided to be, particularly preferably subjected to a vacuum. Particularly preferred is a treatment up to the head extending space is formed between the outer casing and the inner casing, through which a medium, in particular a gaseous medium is feasible. This gaseous medium is used in particular for cooling of the exit window and to this end the gaseous medium along the inner casing is fed to the treatment head and also past the exit window. Preferably so that a space is formed in the form of a channel or several channels between the outer housing and the inner housing, wherein particularly preferably a lower end portion of the outer housing is designed so that the gas stream is led past also, for example, in the radial direction of the device and thus also to the exit window becomes. It should be noted that the flow of the gaseous medium and not, at least not directly reaches the inner wall of the container, but, as stated, serves in particular to be guided past the exit window.

p0017the gaseous medium is advantageously selected from a group of gaseous media which helium, nitrogen, argon, carbon dioxide, mixtures thereof or the like.

p0018The exit window is particularly preferably made of a material which is selected from a group of materials consisting of titanium, fused silica, diamond, combinations thereof and the like.

p0019Thus, in this embodiment at least a part of the apparatus is double-walled, wherein between the outer casing and the inner casing, a gas or air for cooling of the steel pipe, ie of the inner housing and the window is enabled. As mentioned, the interior of the inner housing is evacuated and preferably carries the exit window at the end of a titanium window. In a further preferred embodiment, the exit window has a thickness which is between 3 microns and 30 microns, preferably between 4 micron and 25 microns and more preferably between 5 microns and 20 microns. Thus, it is possible to use for a window, the exit window foil for example of titanium with a thickness of 8 microns, 10 microns, 13 microns and 15 microns. However, it may also be another suitable material be used. This exit window and the window foil to the inner housing, which is also made of a suitable material (such as. For example, also made of titanium) is vacuum-tightly welded. It is possible that the exit window is tensioned cantilevered over the opening of the inner housing, however, it is also possible that a supporting structure such as a perforated plate is provided, which supports the exit window. In case of using a supporting structure for the exit window, it is also conceivable that this support structure is cooled by a suitable fluid, which is discharged through one or more channels between the inner housing and the outer housing to the support structure every now and then.

p0020In a preferred embodiment, the exit window over its surface away to a uniform thickness. However, it would also be conceivable depending on the application, that the thickness varies, for example increases from the outside inwards. So it is possible that the window film has also over its surface across different thicknesses, for example, swaying 4-13 microns, or even in the form of a Dickenperforation in lines or dots. In this way, it is possible to differently fast electrons in the atmosphere, that is to receive the outer side of the exit window and thus of a conventional stray field deviating stray field.

p0021As mentioned above, different gases may be used as the cooling gas. In this way, an improved heat transfer of the gases to be achieved, especially with helium but it would also be possible to influence the conditions for the electrons in the atmosphere, that is, after exiting from the exit window. Thus, for example, leads to the use of helium as the atmosphere to form larger ranges of electrons because helium has a lower density than air. Further, ie the interior of the container, achieved by feeding the gases, a inertization of the treatment space, which in turn leads to a reduction in the ozone formation.

p0022As beam generator can be both an open and a closed electron beam unit, for example, are made of X-ray tubes and the like is known, used. The electron source itself may be made of point-like or planar electron source to which the inner casing or the emitting finger is directly attached.

p0023The device of the invention is hereinafter referred to as beam fingers.

p0024In a further advantageous embodiment, the device comprises a deflection unit for deflecting the charge carriers. Particularly preferably, this deflector is located between the charge carrier generating source and the exit window. Thus, an electromagnetic deflection of the electrons take place before the exit window to give the electrons in addition a preferred direction in the direction of the bottle wall. In this way it is possible to distribute the radiation dose more evenly across the inner surface of the container. It is also possible in this manner, the electron beam uniformly over the entire exit surface of the exit window to lead in order to achieve in this way a more uniform stress of the exit window in its entirety or to the so-called it. Hotspots on the window to prevent. However, it is also conceivable that the deflection unit is arranged in the direction of the electron beam to the exit window.

p0025Preferably, the inner housing in the region of the treatment head an enlarged inner diameter in order to simplify these mentioned deflection of the charge carriers.

p0026Furthermore, the treatment head is particularly preferred over the containers in a longitudinal direction of the container is movable. In this way, a larger-scale section of the inner wall of the container can be sterilized in one operation.

p0027In a further advantageous embodiment of the treatment head relative to the receptacle is rotatable. This is particularly advantageous if the carrier leak in a preferred radial direction relative to the treatment head. In a further advantageous embodiment of the treatment head relative to the container in a radial direction of the container is movable. Thus, it is possible, for example, that is pivoted about a predetermined pivot axis during the sterilization process, the treatment head itself or the device or that the container itself is tilted relative to the treatment head. In this case, a pivot axis in a region of the mouth of the container and is provided slightly above the mouth of the container particularly preferred. In this way, the treatment head can be brought close to the inner wall of the container.

p0028The present device is further directed to an arrangement for the handling of containers with at least one device of the type described above. Preferably, a plurality of the devices described above are next to one another or behind one another in order to sterilize several containers simultaneously. For example it is possible to perform the entire assembly as a rotary or linear actuator, wherein a treatment chamber is provided, which serves for internal sterilization of beverage bottles by electron beams. So it is also possible to integrate the device of the invention in a stretch or a filling or order as stand-alone unit, to retrofit existing lines or arrangements can.

p0029Preferably, the arrangement has a device for filling containers and the inventive device is disposed upstream with respect to this device.

p0030Furthermore, the arrangement may comprise a displacement device which moves the containers in the longitudinal direction of the containers relative to the apparatus. In principle, it would also be possible to maintain the height of the containers, and only to move the device in the longitudinal direction of the containers. However, since the device or the beam fingers are relatively intricately designed and usually applied with high voltages, it makes sense to rather to hold them steady and rather to move the containers relative to the apparatus.

p0031Furthermore, the device between an expansion device for the containers and means for filling the containers is advantageously arranged. Thus, a sterilization of this arrangement is performed after expansion of the containers or the bubbles of the containers.

p0032Advantageously, the arrangement comprises a plurality of devices of the type described above, which individual apparatuses are particularly preferably arranged along a circular path. However, it would also be possible to arrange a plurality of devices along a substantially straight path, for example, parallel to a straight line extending in the conveyor belt.

p0033The present invention is further directed to a method for the sterilization of containers, wherein in a device for sterilizing of the containers produced charge carriers and accelerated in the direction of an exit window, this exit window is arranged in a treatment head. According to the invention the treatment head of the device is inserted through a mouth of the container into the interior of the container and from the treatment head accelerated charge carriers are directed to the inner wall of the container and the container preferably moved relative to the treatment head.

p0034Preferably, the charge carriers before reaching the exit window are deflected in a radial direction of the container and the device. Coils or the like can be used for this deflection.

p0035Further advantages and embodiments will be apparent from the accompanying drawings:<ul><li>Therein:<dl id="dl0001"><dt>Fig. 1A</dt><dd>a partial view of an apparatus for sterilizing containers;</dd><dt>Fig. 1B</dt><dd>an outer casing for the device of <figref idrefs="f0001">Fig. 1A</figref>;</dd><dt>Fig. 1C</dt><dd>an inner housing for the device of <figref idrefs="f0001">Fig. 1A</figref>;</dd><dt>Fig. 1d</dt><dd>a supporting body with exit window for the apparatus of <figref idrefs="f0001">Fig. 1A</figref>;</dd><dt>Fig. 1e</dt><dd>a plan view of the support window <figref idrefs="f0001">Fig. 1d</figref>;</dd><dt>Fig. 1f</dt><dd>a plan view of the exit window from <figref idrefs="f0001">Fig. 1A</figref>;</dd><dt>Fig. 1g</dt><dd>a further embodiment of a support window;</dd><dt>FIG. 2</dt><dd>a further embodiment of a device according to the invention;</dd><dt>Fig. 3</dt><dd>a further embodiment of a device according to the invention;</dd><dt>Fig. 4</dt><dd>an arrangement for treating containers;</dd><dt>Fig. 5</dt><dd>another example of an arrangement for treating containers; </dd><dt>Fig. 6</dt><dd>a detailed view of an arrangement for treating containers;</dd><dt>Fig. 7</dt><dd>sectional schematic side view of an arrangement for treating containers and</dd><dt>Fig. 8</dt><dd>a further embodiment of a device according to the invention.</dd></dl></li></ul>

p0036<figref idrefs="f0001">Fig. 1A</figref> shows a partial representation of an apparatus for sterilizing containers. This device comprises at its lower end to a treatment head 5 to which an exit window 8 is provided through which an electron beam can escape. At this time, as usual in the prior art, first, for example by means of a tungsten cathode, the electrons generated. These electrons are then accelerated through a (not shown in detail) accelerator. 6 As electron generation source punctiform or planar electron sources can be used.

p0037The device 1 for the sterilization of containers comprises an outer housing 16 and an inner housing 20, and is thus double-walled. Between the outer housing 16 and the inner casing 20, a gap 22 is formed, along which air, another gaseous medium or a liquid medium can be guided. In this case, the air gap 22 may be formed circumferentially in the circumferential direction, but it is also possible that a plurality of channels 22 is provided. In principle, it is possible, that the gas jet is guided past the exit window 8 during operation of the device 1 in the radial direction R, however, it is also possible that the gas flow is led past in the time period at the exit window 8, in which the device 1 is not active or the radiation source is not active. In this way it can be prevented that the emerging electron beam is influenced by the air flow. It is pointed out that the gas stream is used exclusively for cooling the exit window and not for guiding the electron beam.

p0038In principle, the beam current is in the case of an optimally selected acceleration voltage of maßgebenende factor, to produce the corresponding necessary dose in the container in the shortest possible time. However, this beam current leads in the exit window 8 in losses 8 sooner or later limit the maximum beam power of electron beam unit or device 1 depending on the execution of this exit window. With the described air, gas or liquid cooling, but also the necessary cooling of the exit window can be ensured. In other words intended to achieve the maximum possible beam current is minimized ie the maximum possible throughput, the number of ejection units or the clock time can be increased. It would also be possible to improve the scattering geometry of the atmosphere that is, outside of the exit window eighth

p0039The electrons are at energy in a range of 100 keV - 200 keV preferably accelerated between 120 keV and 180 keV, preferably 130 keV and 170 keV.

p0040<figref idrefs="f0001">Fig. 1B</figref> shows an outer housing 20 for an inventive device 1. It can be seen that 20 in the radial direction inwardly projecting walls 11 are provided at the lower end of the outer housing. These walls 11 are used for air or gas guide that they cause gas are at least guided past also sections exit window. 8 Through these walls 11 an opening 15 is further formed, through which also the resulting electron can escape to the outside.

p0041However, it would also be possible to supply gas 20 on one side with respect to the inner housing and this discharging on the other side of the inner housing 20 again.

p0042<figref idrefs="f0001">Fig. 1C</figref> shows an inner casing 20. This inner casing 20 has at its lower end or to the treatment head 5 has a recess 24 to receive the exit window 8 and also a supporting body 26 of the exit window eighth

p0043<figref idrefs="f0001">Fig. 1d</figref> shows a support body 26 for supporting the actual in <figref idrefs="f0001">Fig. 1f</figref> shown the exit window 8 is used. In this embodiment, this supporting body 26 forms a plurality of channels 26a, through which the electron beam may occur. In addition, the supporting body 26 may have channels through which a cooling liquid or a cooling gas can be passed through the.

p0044This in <figref idrefs="f0001">Fig. 1f</figref> actual exit window 8 shown is for example welded to the support body 26th

p0045For the inner casing 20 or the entire device 1 different embodiments are conceivable. Thus, it is possible to execute the device, for example of quartz glass, that is to say in particular run the inner tube 20 of quartz glass. It can for instance be melted down as the exit window 8, a thin silica film. Such films having a thickness of 20 microns are already known from the prior art. The density of such windows is in a range of 2.2 g / cm³ and corresponding to 44 g / cm², This corresponds to the surface density of a titanium film having a thickness of 10 microns.

p0046Such quartz glass films permit operating temperatures up to 1000 ° C that is for cooling a high temperature gradient is also possible. Another advantage of such glass films made of quartz glass, the quartz glass films are elastic in this thickness.

p0047Another possibility would be to make the apparatus 1 and the inner casing 20 made of quartz glass and the exit window 8 of diamond. Here, too, sheets having a thickness of 10 microns are already known. Such films have a density in the range of 3.5 g / cm³ or 35 g / cm² on. The advantage of such films of diamond have a further improved thermal conductivity, for example, exceeds the thermal conductivity of copper by a factor of the fifth

p0048Furthermore, it would also be possible to make the device 1 including, in particular the inner tube or inner housing 20 made of metal (eg. As titanium) and the exit window 8, as mentioned above, made of diamond with the characteristics referred to above. It would be possible that the exit window 8 is soldered or fused. If glass tubes are used, they should be metallized advantageous because over the relatively long distance can occur boots.

p0049<figref idrefs="f0002">FIG. 2</figref> shows a further embodiment of an inventive device 1. In this case, the inner casing 20 and inner pipe at the top of a relatively small internal cross section that widens in the region of the treatment head fifth In this manner, a relatively large space 22 is formed between the inner housing 20 and outer housing sixteenth In the area of ​​the treatment head 5, the inner housing has a conically enlarged end portion 21st With this end portion 21, it is possible to direct the electron beams under relatively high angle. To deflect the electron beam, for example deflection coils 7 may be provided. Because in addition to the in<figref idrefs="f0002">FIG. 2</figref> shown coil pair arranged yet another vertically positioned pair of coils, the electron beams can be sent out in principle in all directions. When in<figref idrefs="f0002">FIG. 2</figref> illustrated embodiment is only 8 provided an exit window in the form of a titanium foil. It could, however, also a support body 26 as in the<figref idrefs="f0001">1a</figref> his or 1e provided.

p0050Instead of in <figref idrefs="f0002">FIG. 2</figref> However conical extension shown could also be formed, for example, hemispherical, the lower portion 21st Furthermore, it would also be possible that the deflection coils are arranged outside of the outer housing sixteenth It would also be possible to arrange the deflection coils only below the device first When in<figref idrefs="f0002">FIG. 2</figref> illustrated embodiment is also the inner housing 20 is formed of titanium.

p0051<figref idrefs="f0002">Fig. 3</figref> shows a further embodiment for a device according to the invention. In this device, a relatively thin air gap 22 is provided between the inner housing 20 and outer housing sixteenth In order to avoid contacts between the inner housing 20 and outer housing 16, it is possible, between the two housings 16, 20 to arrange the spacer body 17, wherein the spacer bodies 17 are advantageously electrically insulated. As with the in<figref idrefs="f0002">FIG. 2</figref> illustrated embodiment could also occur with the in <figref idrefs="f0002">Fig. 3</figref> illustrated embodiment, deflection coils 7 may be provided for deflecting the electron beam.

p0052<figref idrefs="f0003">Fig. 4</figref> shows an inventive arrangement for treating containers. This arrangement has sorter 40 for preforms, preferably designed as a rotating disc sorting means 40 and a heating or an oven 35 to be heated in the preforms. At this heating distance to a blower 38 connects, which blows the preforms into containers. Next to this there is a blowing device or a plurality of devices 1 according to the invention for sterilizing the containers already blown. Here, reference numeral 18 denotes a shielding means, such as a lead sheath surrounding the entire apparatus 1, to prevent the escape of X-rays.

p0053The reference numeral 19 refers to a transport element which transports the containers by the blowing device 38 to a filling device 32nd Thus, a blow device 38 are followed by a filling 32 and possibly subsequently also provided a labeling machine in the direction of movement of the containers initially. However, it would also be possible, that the blower 38, first, a labeling machine and a filling device 32 then follows. In the inventive arrangement, the device 1 is in each case arranged immediately downstream of the blowing device 38th

p0054It would be further possible to provide in addition to the device 1 according to the invention, other similar types of sterilization devices which serve for cleaning the exterior that is, the sterilization of the outer walls of the containers. The individual containers can be performed on a rotary machine for internal sterilization and then each of the inventive devices are immersed in the containers. It is, as mentioned above, advantageous to keep the individual devices or emitting finger at a constant height level and move the containers towards them.

p0055In other words, the beam fingers 1 are immersed for the internal sterilization in the containers. Most preferably, the individual containers are passed in rotation to each inventive devices. However, it is additionally also possible to drive past the individual containers to a curtain with electron beams, to effect in this manner an outer sterilization.

p0056<figref idrefs="f0003">Fig. 5</figref> shows a detailed view of a further inventive arrangement of a sterilization apparatus.

p0057In principle, it is possible that the containers transported by a chain or be carried by a chain in a treatment room and plunge there jet finger over a lifting movement in the bottle. It would also be possible to pass the containers on a star in the neck handling to a sterilization facility and to move there over a stroke on the beam fingers.

p0058When in <figref idrefs="f0003">Fig. 5</figref> illustrated embodiment is initially through an irradiation device 1b an external irradiation of the containers, preferably during a rotation thereof. It accelerated electron beams are used to irradiate each to about 150 keV. Is then carried out an internal irradiation of the containers in the manner described above by the apparatus 1a.

p0059<figref idrefs="f0004">Fig. 6</figref> shows a schematic illustration of a method according to the invention for the internal sterilization of containers 10. The containers 10 are brought in via a conveyor belt 19 in the direction of arrow P, and brought to a sterilization arrangement via an inlet star 27th In a first sector I is initially a Ausfahrwinkel of 135 °, a lowering of the jet fingers in the interior of the containers 10 and a lifting of the containers 10. In a further sector II the beam fingers are moved back and the containers 10 are lowered. During this extension of the ray finger from the containers 10, the device 1 is activated and carried out in this way an internal sterilization of the containers 10th

p0060Then the containers are transported via an outlet star 28th

p0061<figref idrefs="f0004">Fig. 7</figref> shows a schematic representation of the external gear 31. This planet wheel 31 has a plurality of devices 1 according to the invention, which are each arranged at the same height, however, it can be seen that the individual containers are lifted 10 up to a maximum position and in this way the device 1 or the beam finger, depending on the rotation position are different depths immersed in the containers 10th During this entire process, the inventive devices 1 are activated and in this way the inner wall of the containers 10 is sterilized over the entire height of the containers the first The length of the beam finger is chosen such that an effective sterilization of the floors of the containers 10 is possible.

p0062<figref idrefs="f0005">Fig. 8</figref> shows a further embodiment for a device according to the invention. In this device, the area between the inner housing 20 and outer housing 16 is designed such that the formation of two gas channels 22a and 22b. The gas stream is supplied by one of the two channels 22a and clips laterally evenly over the outlet window 8, through the other channel 22b of the gas stream can be discharged again.

p0063All features disclosed in the application documents are claimed as essential to the invention, provided that they individually or in combination, over the prior art are new.