Abstract
Electron beam emitter, in particular for sterilization of packaging material, comprising a housing and an insert, wherein the housing comprises a first annular channel for guiding a medium, and wherein the first annular channel at least partially surrounds the insert and is adapted to provide the medium, characterized in that the first annular channel is at least partly formed by the insert.
Claims
1. Electron beam emitter, in particular for sterilization of packaging material, comprising a housing and an insert, wherein the housing comprises a first annular channel for guiding a medium, and wherein the first annular channel at least partially surrounds the insert and is adapted to provide the medium, the first annular channel being at least partly formed by the insert.
2. Electron beam emitter according to claim 1, wherein the insert is adapted to form part of an electron exit window (26).
3. Electron beam emitter according to claim 1, wherein the housing comprises a first body and a second body, wherein the first body comprises a cathode housing and a filament, and wherein the insert is arranged at the second body.
4. Electron beam emitter according to claim 1, wherein the insert comprises a support structure and a wall structure, wherein the wall structure forms at least partly the first annular channel.
5. Electron beam emitter according to claim 1, wherein the insert comprises a support structure, wherein the electron beam emitter comprises a foil element, and wherein the foil element is arranged to be supported by the support structure.
6. Electron beam emitter according to claim 1, wherein the insert comprises a partition wall, wherein the partition wall forms at least partly a second annular channel.
7. Electron beam emitter according to claim 6, wherein the insert comprises at least one opening, and wherein the at least one opening is adapted to provide a connection between an internal space of the housing and the second annular channel.
8. Electron beam emitter according to claim 5, wherein the foil element is arranged at a retainer, and wherein the retainer is arranged at the housing.
9. Electron beam emitter according to claim 1, wherein the housing comprises at least one inlet channel and at least one outlet channel which are in fluid connection with the first annular channel, and which are adapted to supply the medium to the first annular channel, and wherein the housing comprises at least one connection port for the inlet channel and at least one connection port for the outlet channel, said connection ports being connected to a medium supply.
10. Electron beam emitter according to claim 1, wherein the housing comprises at least one cover plate (44), wherein the at least one cover plate (44) is adapted to form an outer surface (47) of the housing and to at least partly form the inlet and outlet channel.
11. Electron beam emitter according to claim 1, wherein the housing comprises a tubular element (46), wherein the tubular element and the insert form the first annular channel.
12. Electron beam emitter according to claim 9, wherein the inlet and outlet channels debouche at mutual opposite positions in the first annular channel such that the medium, upon entering the first annular channel from the inlet channel, will be divided into two flows one taking a clockwise direction and the other a counterclockwise direction towards the outlet channel.
13. Electron beam emitter according to claim 1, wherein the medium is water or other liquid coolant.
14. Sterilization device, in particular for packaging material, comprising a power supply unit and at least one electron beam emitter, wherein the electron beam emitter comprises a housing and an insert, wherein the housing comprises a first annular channel, and wherein the first annular channel surrounds the insert, wherein the first annular channel is adapted to provide a medium, wherein the first annular channel is at least partly formed by the insert.
Description
[0023] Additional aspects and features of the current invention are shown in the following description of preferred embodiments of the current invention with reference to the attached drawings. Single features or characteristics of respective embodiments are explicitly allowed to be combined within the scope of the current invention.
[0024] FIG. 1: shows a principle scheme of an embodiment of an electron beam emitter;
[0025] FIG. 2: shows a cross section of a second body of an electron beam emitter;
[0026] FIG. 3: shows an embodiment of an insert from an inside of a housing;
[0027] FIG. 4: shows an embodiment of an insert arranged at a housing;
[0028] FIG. 5a: shows an intersection plane for the sectioning of FIG. 5b;
[0029] FIG. 5b: shows the sectioning as indicated in FIG. 5a;
[0030] FIG. 6: shows a further embodiment of an electron beam emitter;
[0031] FIG. 7: shows the arrangement of an insert at a housing;
[0032] FIG. 8: shows a further embodiment of an insert and its arrangement at a housing.
[0033] Referring now to FIG. 1, an electron beam emitter 20 is shown wherein the electron beam emitter 20 comprises a housing 40. The housing 40 comprises a first body 21 and a second body 22. Both bodies 21, 22 extend along a longitudinal centre axis A. Cross sections of the first body 21 and the second body 22 are basically round, in particular circular, wherein a diameter of the first body is bigger than a diameter of the second body 22. According to one or more embodiments, the first body 21 comprises a cathode housing and a filament (not shown in FIG. 1). Amongst others, the bigger diameter of the first body 21 which comprises the above named components decreases the risk of electric arcs. According to one or more embodiments, the first body 21 is connected or connectable, respectively, to a power supply unit (not shown in FIG. 1). The second body 22 and at least a part of the first body 22 comprise a vacuum, i.e. form a vacuum chamber. The second body 22 comprises cover plates 44, a tubular element 46 and a retainer 29 that forms an end of the housing 40. A sectional view of the second body 22 that is indicated by the small arrows is explained in FIG. 2.
[0034] FIG. 2 shows a lower part of the second body 22 of the housing 40. An insert 60 is arranged at an end portion of the housing 40. In particular, an end portion 67 of the insert 60 is arranged at a wall 50 of the housing 40. In other words, the shape of the cross section of the wall 50 is continued by a wall structure 62 of the insert 60. Hence, the wall structure 62 is annular, i.e. formed as a sleeve or a shell with an extension along longitudinal axis A. The insert 60 comprises also a disc-shaped support structure 64 that has a radial extension being basically perpendicular to the longitudinal axis A of the housing 40. The wall structure 62 of the insert 60 forms at least partly a first annular channel 41. The first annular channel 41 is also formed by a tubular element 46 that is arranged at the wall 50. Cover plates 44 and the wall 50 of the housing 40 form inlet and outlet channels 52, 54 that extend basically along the longitudinal axis A. The inlet and outlet channels 52, 54 are connected to the first annular channel 41 at mutual opposite locations. The first annular channel 41 is limited along the longitudinal axis A by a partition wall 66 that basically surrounds the perimeter of the wall structure 62. The partition wall 66 forms at least partly a second annular channel 42. The second annular channel 42 is connected to an internal space 48 of the housing 40 via an opening 68 that is arranged at and/or in the insert 60. The insert 60 or its wall structure 62, respectively, forms a seamless inner surface 49. Due to the connection of the internal space 48 to the second annular channel 42 via the opening 68 a vacuum that is inside the housing 40 is also in the second annular channel 42. Therefore, a foil element 28 and a retainer 29 can be optimally arranged at the support structure 62 and at the housing 40 or the tubular element 46, respectively. The foil is preferably bonded to an outer surface of the retainer, e.g. by diffusion bonding. The outer surface of the retainer 29 is arranged at a distance, along the longitudinal axis A, from the outer surface of the support structure 62. Thereby, the bonding line of the foil is formed on a plateau, i.e. elevated, compared to the outer surface of the support structure 62.
[0035] FIG. 3 shows an end portion of a housing 40. In particular, an insert 60 is shown from an inside of the housing 40. The housing 40 is formed by a wall 50, wherein inlet and outlet channels 52, 54 are formed by the wall 50 and appropriate cover plates 44. The cover plates 44 and the wall 50 form an outer surface 47 of the housing 40. In the same way, the outer surface 47 is continued by a tubular element 46 that surrounds the insert 60. The insert 60 comprises a support structure 64 and a wall structure 62, wherein the wall structure 62 and the wall 50 form an inner surface 49 of the housing 40. An internal space 48 of the housing 40 is connected to a second annular channel (not visible) via at least one opening 68. The tubular element 46 may be an integrated, i.e. in one piece formed, portion of the rest of the housing 40.
[0036] FIG. 4 shows an embodiment of an insert 60 that is arranged at the housing 40. A tubular element 46 is arranged at the housing 40. However, the tubular element 46 is shown transparent so that a shape of an inlet channel 52 can be seen. The outlet or inlet channel 52, 54 is connected to a first annular channel 41 that is formed by the insert 60 and in particular by a wall structure 62 of the insert 60. The outlet channel is not visible in FIG. 4 since it is being located opposite the inlet channel 52. The flow of the medium entering the first annular channel 41, from the inlet channel 52, will be divided into two flows, one directed clockwise towards the outlet channel and the other directed counterclockwise towards the outlet channel. Arrows illustrate this. An end portion 67 continues the form and design of a wall 50 of the housing 40. The inlet or outlet channel 52, 54 is formed by the wall 50 of the housing 40 and a cover plate 44. The cover plate 44 forms together with the wall 50 of the housing 40 an outer surface 47. The insert 60 comprises a partition wall 66 that is adapted to form at least partly a second annular channel 42 (see FIG. 2), wherein a connection from an internal space of the housing 40 to the second annular channel 42 can be realized by a plurality of openings 68. The insert 60 comprises a grid- or web-like support structure 64.
[0037] FIG. 5a just shows an intersection plane of an embodiment of an electron beam emitter 20 comprising a first body 21 and a second body 22, wherein the second body 22 comprises an electron exit window 26. The small arrow indicates a viewing direction for the sectioning shown in FIG. 5b.
[0038] FIG. 5b shows a filament 24 that is arranged inside the first body 21 of a housing 40. Two semicircular pockets are shown that merge to the already known shape of the inlet and outlet channels 52, 54, as for example shown in FIG. 4. This allows a basically perpendicular deflection of a (cooling) medium flow from connection ports 56 to the inlet and outlet channels 52, 54 respectively. The connection ports 56 are indicated by the dotted lines.
[0039] FIG. 6 shows a further embodiment of an electron beam emitter 20 comprising a housing 40, wherein the housing 40 comprises a first body 21 and a second body 22. The housing 40 extends along a longitudinal axis A, wherein the second body 22 comprises an electron exit window 26 with a foil element 28 at its end portion. Between the first body 21 and the second body 22 there is arranged a kind of flange, wherein the flange comprises two connection ports 56 that are adapted to supply a cooling medium. In addition, the flange comprises four openings or holes that can be used to arrange the electron beam emitter for example at a movable or rotatable carousel or carrier plate.
[0040] FIG. 7 shows a principle scheme of an arrangement of an insert 60 at a housing 40. The housing 40 comprises a wall 50 (without cover plates). The insert 60 comprises a wall structure 62 and a support structure 64. A first annular channel 42 is formed by the insert 60 and in particular by the wall structure 62 and by a partition wall 66. The partition wall 66 forms furthermore a second annular channel 42 that is connected via an opening 68 to an internal space 48 of the housing 40. A foil element 28 and a retainer 29 can be easily arranged at the insert 60 and the housing 40 e.g. moving it along the direction of the small arrow that extends along the longitudinal axis A.
[0041] FIG. 8 shows a further embodiment of an insert 60 that comprises a support structure 64 and a wall structure 62. However, the arrangement at a housing 40 that comprises inlet and outlet channels 52, 54 is different. In particular, the housing 40 forms a kind of flange, wherein the insert 60 can be arranged at the flange via appropriate fixing material, e. g, indicated by the dashed lines. A foil element and its arrangement are not shown in FIG. 8.
[0042] The electron beam emitter may be connected to a conditioning system as described in the Swedish Patent Application No. SE 1450217-3 filed by the applicant. In such system the cooling medium is first used to cool a power supply unit connected to the electron beam emitter. Hence, the flow direction of the medium is directed from the power supply unit to the electron beam emitter. Generally, the temperature level of the power supply unit is lower than a temperature level of the electron beam emitter. This means that the medium flow that has already been heated up during cooling of the power supply unit can still be used for cooling the electron beam emitter and in particular its electron exit window. Further, it is an advantage if the electron exit window is cooled with a medium flow that is warmer than an ambient temperature of the electron exit window. In that way condensation on the electron exit window may be avoided.
[0043] The electron beam emitter 20 according to the invention can be arranged in an irradiation chamber in a filling machine. The filling machine comprises at least one filling station for filling content into the packaging container and at least one station for sealing the opening after filling. The electron beam emitter can for example be applied in the application described in the international application No. PCT/EP2013/076870 filed by the applicant. A plurality of emitters can be provided on a carousel or the like which is adapted to rotate. The emitters may be arranged in holes in the carousel. The packaging containers, which are transported for example via a conveyor, reach the carousel and are engaged with one of the (rotating) emitters for interior surface sterilization. During at least a part of one rotation of the carousel the interior sterilization takes place. During interior sterilization a relative movement is created between the packaging container and the electron beam emitter, in particular the packaging containers are lifted to surround the electron beam emitters such that the electron cloud emitted through the electron exit window is inserted into the packaging container and can reach the interior surface thereof. After sterilization the packaging container is removed from the emitter or from the carousel, respectively. The packaging container is then subsequently transported through an electron cloud provided in a gap between two emitters for outside surface sterilization.
REFERENCE NUMERALS
[0044] 20 electron beam emitter [0045] 21 first body [0046] 22 second body [0047] 24 filament [0048] 26 electron exit window [0049] 28 foil element [0050] 29 retainer [0051] 40 housing [0052] 41 first annular channel [0053] 42 second annular channel [0054] 44 cover plate [0055] 46 tubular element [0056] 47 outer surface [0057] 48 internal space [0058] 49 inner surface [0059] 50 wall [0060] 52 inlet channel [0061] 54 outlet channel [0062] 56 connection port [0063] 60 insert [0064] 62 wall structure [0065] 64 support structure [0066] 66 partition wall [0067] 67 end portion [0068] 68 opening [0069] A longitudinal axis
