RADOME-FREE ANTENNA UNIT

Description

I. Area of ​​application

[0001] The invention relates to antennas, mostly high-frequency antennas for the frequency range from 1 GHz to about 40 GHz, which both transmit and receive, as they are arranged in particular in pressure-tight rooms with a cable connection through the metallic wall of the pressure-tight room to the outside. II. Technical background

[0002] A typical application is the pressure vessel of a freeze-drying system. Depending on the process, the process temperature varies from approximately -70 °C to approximately +120 °C, and the process pressure varies from atmospheric pressure or even negative pressure to typically 3 bar above atmospheric pressure.

[0003] In order to wirelessly query the temperature of temperature sensors positioned in the products, an antenna of an antenna unit, which usually includes an antenna at the level of each of the levels of the pressure vessel, sends out a request signal, which also provides the temperature sensor, which does not have its own power supply, with the energy to not only measure the temperature, but also to send a response signal representing the measured temperature back to the antenna.

[0004] A cable connection, usually using coaxial cables, leads from the antenna unit to the outside. This cable must be routed pressure-tight through the wall of the pressure vessel and is connected outside the pressure vessel to an electronic interrogation unit or the control unit of the freeze-drying system there.

[0005] It is known to use an antenna unit that is built on an antenna base and protected inside a radome, i.e. a usually dome-shaped protective housing, due to the consideration that the antenna unit then has only a single sealing point, namely between the radome and the antenna base, which must be permanently sealed, apart from the cable feedthrough from there through the wall of the pressure vessel.

[0006] However, the radome must be permeable to radio waves, so it must almost necessarily be made of plastic, while all other parts, especially the antenna base, are made of stainless steel due to existing hygiene regulations.

[0007] Due to the completely different physical behavior of plastic on the one hand and stainless steel - usually of the type 1.4.4.2004 / AISI 31GL-FDA / GMP or 1.4.4.2004 / AINSI 316L - on the other hand, maintaining the tightness in the long term is a problem under the above-mentioned operating conditions when pressure and / or temperature changes.

[0008] Furthermore, the operators of freeze-drying plants want, if possible, that all additional components in the pressure vessel are made only of materials that are already present in the vessel and are therefore approved, especially from a hygienic point of view, since freeze-drying plants usually produce food or pharmaceuticals that are even more sensitive in terms of process conditions.

[0009] The document US 2021 / 047919 A1 discloses an antenna unit according to the preamble of claim 1. Furthermore, reference is made to the documents CN 211 350 926 U and US 2020 / 342186 A1. III. Description of the invention a) Technical task

[0010] It is therefore the object of the invention to provide an antenna unit and in particular a freeze-drying system equipped therewith, as well as a method for producing and assembling the antenna unit, which minimizes or completely solves these problems. b) Solution to the task

[0011] This object is achieved by the features of claims 1, 16 and 18. Advantageous embodiments emerge from the subclaims.

[0012] Regarding the Antenna unitThis task is solved in that the antenna unit - usually comprising several individual antennas - comprises on the one hand an antenna part, which also carries the several individual antennas, and a feed part, through which one or more cables, in particular high-frequency cables - which can each consist of several cable sections one behind the other - are fed in a protected manner to the antenna part and the antennas there.

[0013] The antenna part is attached to the feed part by means of a flange block, and can be removed without destroying the connection, for example by loosening a screw connection, which should be possible in less than 1 to 2 minutes.

[0014] After opening the flange block—that is, separating the two block sections, which are usually cap-shaped and can be pressed tightly against each other with their open sides—the cable sections of the cables routed through it are accessible at this point and easily detachably connected to each other in the flange block using a cable coupling, either a plug-in coupling or, in particular, a plug-in coupling that also requires the loosening of a union nut. In this way, the cable sections of the feeder section can be very quickly separated from the cable sections of the antenna section.

[0015] When installed in a pressure vessel, such as a freeze-dryer, the feed section can always remain permanently mounted, while the antenna section with the attached antennas can be easily detached and removed, either to replace a defective antenna or to improve access to components located behind it in the pressure vessel. Since the antennas are usually high-frequency antennas, operating in the range of 1 GHz to 40 GHz, coaxial cables are used as cables and cable sections to prevent signal radiation through the cables themselves.

[0016] In this context, tight means pressure-tight, i.e. gas-tight, especially in the case of pressure differences where the lowest pressure is in the negative pressure range of up to 1 / 10,000,00 bar, in particular 1 / 1,000,000 bar, and the highest pressure is in the positive pressure range of 5 bar overpressure and more.

[0017] In this case, the pressure-tight separation between different spaces can be provided: On the one hand, the interior spaces of the feed part on the one hand and the antenna part on the other hand can be pressure-tightly separated from each other by means of the closed flange block, which then of course requires a pressure-tight feedthrough of the cable section there through the cable through-opening of the corresponding block part at least in one of the two block parts.

[0018] In any case, the interior spaces of the feed part on the one hand and the antenna part on the other hand - regardless of whether they are pressure-tightly separated from each other when the flange block is closed or are pressure-connected to each other and form an interior space - are pressure-tightly sealed against the environment of the feed part on the one hand and / or the antenna part on the other hand.

[0019] When installing the antenna unit in a pressure chamber, e.g. a freeze-drying system or a sterilization system, the interior of the feed part and / or the antenna part can still have a connection to the environment of the pressure chamber in such an assembled state.

[0020] An SMA coupling is preferably used as the cable coupling, wherein the antenna-side coupling part of the cable coupling, in particular an SMA coupling, is preferably not only fixed to the antenna part, in particular the antenna-side block part of the flange block, as is usual by screwing, but is also glued or welded to it in a pressure-tight manner.

[0021] This prevents any leaks at the cable outlet, e.g. of the antenna part.

[0022] Preferably, the antenna part comprises a hollow, in particular tubular, support body, which is preferably made of metal, in particular stainless steel, wherein preferably the same material, in particular the same type of stainless steel, is used for the entire antenna unit as far as possible as for the pressure vessel itself.

[0023] The corresponding cable sections are led from the flange block through the hollow support body to the usually several antennas that are tightly attached to the support body. A cable section coming from the flange block can also branch out in the support body and supply several antennas, which then activate the antennas with a time delay via an antenna multiplexer, which is usually included in the control system.

[0024] To ensure the hollow support body is sealed from the environment, the individual antennas are mounted on, above, or at a respective opening in the wall of the support body through which the cable reaches the back of the antenna, so that this opening is sealed pressure-tight by the antenna. The antenna is preferably made of the same material as the support body, preferably stainless steel, and can therefore be welded to the support body.

[0025] The most striking difference to previous solutions is that the antenna unit and in particular its antenna part does not have a protective cover in the form of a radome that surrounds the individual antennas in a pressure-tight manner and is connected in a pressure-tight manner to an antenna base or the antenna support body.

[0026] Although the antenna part may have a protective device to protect the antennas present on the antenna part from damage in a purely mechanical way, these do not provide a tight protective cover around the antenna part.

[0027] Thus, the protective device can comprise only a grid or only protective rods running essentially parallel to the tubular support body and arranged around it outside the antennas, which do not pose a problem during the usually automatic cleaning of the interior of the pressure vessel, since they are accessible from all sides, usually drain freely downwards and cleaning fluid can drip freely downwards.

[0028] Since the emission of electromagnetic radiation by the antenna must not be made more difficult, such a protective device such as a grid or protective rods is usually made of plastic, for example from PEEK or polyetheretherketone for reasons of mechanical strength.

[0029] The individual antennas themselves usually consist of a - usually plate-shaped - radiator, i.e. the actual transmitter and receiver of the antenna, as well as a reflector plate arranged behind it at a distance against the radiation direction, which is usually larger than the plate-shaped radiator and whose task is to reflect the electromagnetic waves of the response signal arriving in the area around the radiator in the direction of the radiator and thus to improve, in particular to amplify, its useful signal.

[0030] In this case, "plate-shaped" doesn't necessarily mean that the plates must be flat, nor does it mean that they must be solid or closed. Depending on the frequency and thus the wavelength of the radiation used, both the reflector plate and a plate-shaped radiator can have a variety of openings. In particular, the antenna protection tube can form the reflector in whole or in part.

[0031] Preferably, both the reflector plate and the radiator and / or the spacer sleeve are made of the same material, in particular the same material as the pressure vessel.

[0032] Preferably, a coupling part of a cable coupling is attached to the rear side of the reflector plate facing away from the radiator, to which the cable section in the support body can be connected, e.g. plugged in, before or after welding the reflector plate to the support body in order to seal the corresponding opening.

[0033] The distance between the reflector plate and the radiator can be bridged by a cable section running between the reflector plate and the radiator - which is in particular firmly and permanently attached to the radiator, for example soldered or welded - or by this cable coupling being designed in such a way that it extends from the back of the reflector plate through it and to the back of the radiator, where the inner conductor of the coaxial cable couples the high-frequency oscillation into the radiator.

[0034] In order to seal the interior of the supporting body, either such a cable section or part of the cable coupling must be tightly enclosed, for example by means of a spacer sleeve through a pressure-tight connection to both the reflector plate and the radiator, or the cable coupling, in particular a pressure-tight one, must be attached in a pressure-tight manner to the passage opening of the reflector plate for the coupling or the cable, for example by welding or gluing the coupling flange plate, which is usually attached to the back of the reflector plate by screwing, to the reflector plate after screwing, or by providing the carrier plate with a welded or soldered vacuum-tight high-frequency feedthrough

[0035] In the second case described, additional measures must be taken to ensure that no leakage occurs between the inner conductor protruding on the radiator side of the cable coupling and the surrounding cable coupling into the cable and thus into the interior of the support body.

[0036] This can be achieved, for example, with designs of cable coupling, in particular an SMA coupling, where there is no leakage along the inner conductor in the form of a through-hole through the cable coupling.

[0037] Cable couplings are possible with a capacitive high-frequency coupling of the inner conductors on both sides via a link made of an electrical insulator, for example so-called glass bushings, in which the electrical insulator, for example a glass plate or glass sphere, is welded pressure-tight into the surrounding coupling housing, reaches up to the inner conductor on both sides and contacts them, thus passing the high frequency of the applied alternating current across the electrical insulator.

[0038] Regardless of this, a cable coupling can consist of two coupling parts, each with a cable section attached, which are then coupled together by directly connecting the two coupling parts to each other.

[0039] In addition, a cable coupling can also have three coupling parts, namely an additional middle piece - which is often designed as an adapter - on each side of which one of the two further coupling parts connected to a cable section is attached.

[0040] On one of the two or three coupling parts there may be a radially projecting coupling flange which serves for fixing, in particular screwing, to a component of the surroundings, whereby the entire coupling is then positioned.

[0041] Alternatively, the radiator can also be detachably attached to the reflector plate, in particular screwed, in particular by means of spacers which are mounted at a distance, in particular offset, from the cable connection.

[0042] The hollow support body is thus circumferentially closed by its walls and the openings therein, which are sealed pressure-tight by the antennas, at one end by a block part of the flange block, and at the opposite end by an essentially closed end wall.

[0043] Preferably, in the lower region, in particular at the lowest point, of the hollow support body - in the case of an upright tubular support body which is tightly connected to the feed part at the upper end, in the lower end wall - there is an access opening which can, however, be closed in a pressure-tight manner, for example by being designed as a threaded opening into which a sealing plug can be tightly screwed.

[0044] This access opening, which is closed during normal operation, can be used for various purposes when open: For example, a gassing device can be tightly connected to it, through which an inert gas such as helium can be introduced into the interior of the support body in order to detect, by means of appropriate sensors, whether this gas is present in the area surrounding the support body, which could then only have reached the area through a leak in the support body.

[0045] A leak test can also be carried out in other ways, for example by pressurising the interior of the support body via the access opening with gas at a specified holding pressure, which must not fall below a defined threshold value within a specified time.

[0046] Condensation fluid can also be drained through such an access opening.

[0047] The Flange block, which tightly connects the two parts of the antenna unit, usually comprises two cap-shaped block parts that can be pressed tightly against each other, in particular screwed together pressure-tight, each with a through-opening for the cable(s).

[0048] The free interior space created by the two block sections pressed against each other with their cap edges is large enough to accommodate a cable coupling, with one coupling section being attached to each of the cables inserted into the flange block through one of the through openings. By tightly fastening each of the two coupling sections to the block section that supports it, in particular by gluing or welding it into it, the feed section and antenna section are tightly separated from one another with regard to their interior spaces when the flange block is tightly closed, so that even when the antenna section is removed, the interior of the feed section is not opened, and preferably vice versa. In addition, the feed section with its open plug connections can be hermetically sealed with a sealing cap.

[0049] Welded in this case means that only a circumferential welding of the coupling part relative to the block part is required, not a welding all around the entire side.

[0050] Preferably, the two block parts are made of the same material, in particular the same material as the adjacent feed part and / or support part of the antenna part, in particular stainless steel, and preferably the same material as the pressure vessel.

[0051] The Feed part has a tubular feed body open on both sides, in which runs at least one cable which connects the control to the radiator of the antenna.

[0052] Furthermore, one of the block parts of the flange block is attached, in particular welded, in a pressure-tight manner to one of the open ends of the feed body, namely the antenna-side end.

[0053] At the opposite end of the feed body, facing away from the antenna, there is a wall feedthrough with which the feed body can extend through a corresponding recess in the wall of the pressure vessel and can be sealed against this wall.

[0054] This wall feedthrough can be an integral part of the feed body, for example, by being an annular plate that is tightly welded to the outer circumference of the tubular feed body in order to be sealed and fixed to the wall of the pressure vessel around a change passage.

[0055] Here too, the wall feedthrough is preferably made of the same material as the feed body to which it is attached.

[0056] The supply part can be a shaped part such as a straight or curved, circumferentially pressure-tight pipe, or a circumferentially pressure-tight, flexible hose such as a stainless steel corrugated hose.

[0057] A straight pipe would be preferable, but is not always feasible, since the desired position of the antenna part in the pressure vessel, for example, is usually not aligned with the opening in the wall for the feed part.

[0058] The antenna part and / or the feed part can also comprise a dehumidification unit in order to remove or bind moisture created, for example, by condensation in the interior thereof, for example by means of a moisture-absorbing substance such as silica gel.

[0059] Preferably, such a substance is then arranged in a dehumidification container in an exchangeable manner, for example as a replaceable cartridge, and this container is connected to the interior of the antenna part and / or the feed part via a tight connection, wherein an air flow, for example an annular air flow, can also be actively generated between the two, for example via two tight connections between their dehumidification container and the respective interior.

[0060] Since the antenna unit, or at least its antenna part, can be disruptive for certain work at the installation site, this antenna part can be moved, in particular pivoted, from its operating position to a parking position even when the antenna unit is fully assembled, preferably together with the feed part.

[0061] In order to be able to adjust the antennas attached to the antenna part as precisely as possible with regard to the radiation direction, the support body of the antenna part can be pivoted about its greatest extension direction, i.e. its longitudinal axis, relative to the feed part even in the fully assembled state of the antenna unit and can be fixed in any desired pivot position.

[0062] One Freeze-drying plant usually comprises a temperature-controlled and pressure-controllable pressure vessel and an electronic control arranged outside the pressure vessel, wherein an antenna unit can be arranged inside the pressure vessel in order to wirelessly query the temperature from a plurality of temperature sensors arranged therein, positioned in the product or its containers,

[0063] In such a freeze-drying system, the existing problem is solved in that the antenna unit is designed according to one of the preceding claims.

[0064] In order to be able to arrange the antenna part exactly in a desired position inside the pressure vessel, the latter preferably comprises a holding device inside it, to which the antenna unit, preferably only its antenna part, can be fastened detachably and movably, but fixable in any possible position.

[0065] The wall opening in the wall of the pressure vessel for the antenna unit can be designed - depending on the size and shape of the wall opening of the antenna unit - in such a way that the antenna unit, in particular its feed part, can be inserted through the wall opening from the inside or from the outside.

[0066] Regarding the Procedure for the Producean antenna unit as described above with an antenna part and a feed part for cables to the antenna part, in particular an antenna part as described above, this object is achieved in that for producing the antenna part the cable is inserted into the supporting body of the antenna part, the antenna-side end of the cable protruding from the opening is connected to the antenna, in particular its cable section, the antenna is fastened tightly on or in the opening as a closure of the opening.

[0067] Preferably, the antenna is welded onto the opening.

[0068] The antenna-side end of the cable can be connected to the antenna by detachable contact or detachably only by destroying the connection, in particular by soldering or welding.

[0069] Regarding the Procedure for the Mountan antenna unit, in particular as described above, with an antenna part and a feed part in a freeze-drying plant, in particular as described above, the existing task is solved by the feed part with at least one cable section therein is tightly fastened in the wall passage of the pressure vessel, the antenna part is positioned in front of or after it with at least one cable section therein in a desired position in the pressure vessel and in particular is fixed to a holding device of the pressure vessel, the feed part and antenna part are mechanically pressure-tightly connected to one another via a flange block and with regard to their cable sections.

[0070] Preferably, the supply part is inserted from the outside into the wall passage of the pressure vessel and fixed pressure-tight against the wall of the pressure vessel. c) Examples of implementation

[0071] Embodiments of the invention are described in more detail below by way of example. They show: Figure 1a, b: the antenna unit in two 90° different side views, Figure 2a: the antenna part cut along the line II - II, Figure 2b: a section enlargement. Figure 2a , Figure 3: an axial section through the flange block between the feed part and the antenna part, Figure 4: in enlargement compared to the Figures 1a , b the end of the feed part facing away from the antenna when attached to the wall of the pressure vessel, e.g. a freeze-drying system.

[0072] The Figures 1a , b show that the antenna unit 1 consists of two elongated, bar-shaped parts, which follow one another in the axial direction, namely the antenna part 50, on which the antennas 2 are located, and the feed part 60.

[0073] The purpose of the design is to make the antenna unit 1 itself sealed, including the passage of the cables through the passage 102 of the pressure vessel 100, in order to thereby access the sealed cover hood, usually referred to as a radome, attached to the inside of the wall of the pressure vessel - as in Figure 1b indicated by dashed lines - and to ensure better assembly and accessibility to the antenna unit 1.

[0074] For this purpose, the connections between the hollow tubular feed body 61 of the feed part 60 and the hollow support body 51 of the antenna part 50, which is open at least on one side, must be designed to be tight, as must the fastening of the antennas 2 on the outside of the support body 51.

[0075] The main direction of extension of the antenna unit 1, i.e. the direction in which it has its size of extension, is defined as the longitudinal direction 1' and is usually identical with the longitudinal direction 50' of the antenna part 50, since its supporting body 51 is usually straight, while the feed body 61 can also be bent one or more times, as in Figure 1a visible. Since the antenna unit 1 is often mounted suspended from an upper wall 101a of the pressure vessel 101, the longitudinal direction 1' is often identical to the vertical 10.

[0076] For reasons of ease of assembly and repair, the feed body 61 is usually first mounted in the passage 102 of the wall 101a of the pressure vessel 101, usually inserted into the passage 102 from the outside of the pressure vessel 101.

[0077] The prefabricated antenna part 50 is then attached to it, i.e. the support body 51 with the antennas 2 attached thereto, including the cable sections 3.50 of the cables 3 that are already connected to the antennas and are located in the support body 51 and extend to the upper open end of the support body 51.

[0078] The antenna part 50 comprises a hollow, tubular - in this case with a rectangular cross-section - support body 51 and the feed part 60 a hollow feed body 61, because the antennas 2 must each be connected with a cable 3 - as on the uppermost of the four antennas 2 in Figure 1b shown as an example - which, from bottom to top, runs first in the support body 51 and then in the feed body 61 and extends through a passage 102 in the wall 101a of a pressure vessel 101, so that the cable is connected outside the pressure vessel 1 with a Figure 4 suggested electronic query system 1* the antenna unit 1 of the system to which the pressure vessel 101 belongs.

[0079] In the lower, closed end of the support body 51 there may be an access opening 7, in particular a threaded opening 7, which serves to provide access to the interior of the support part 51, for example in order to gasse the interior with protective gas or for other purposes.

[0080] Figure 1b further shows in the upper area of ​​the feed body 61 on the outside thereof a dehumidification unit 90 with a dehumidification container 91 with a moisture-absorbing content, which is in communication with the interior of the feed body 61 and absorbs moisture present there.

[0081] According to Figure 3the upper, open end of the hollow support body 51 is tightly connected to the lower, open end of the feed body 61 by means of a coupling block 70 which has two block parts 70a, b which can be pressed tightly against one another in the longitudinal direction 50'.

[0082] In this case, the lower block part 70a is placed on the upper end face of the support body 51 and welded to it in a sealed manner all around, whereby this plate-shaped, lower block part 70a is usually bowl-shaped with an upwardly open depression, but above all has passages running in the longitudinal direction 50', into each of which an intermediate piece 4c is screwed, preferably tightly, which has a coupling part both on the side of the feed body 61 and on the side of the support body 51, onto which a coupling part 4a, b can be screwed at the end of a cable section 3.50 or a cable section 3.60.

[0083] The upper, annular block part 70b can be pressed from above against a radially outwardly projecting, annular flange 63 at the lower end of the feed part 61 and this onto a seal 64 which is located between this flange 63 and the lower block part 70a.

[0084] Inside the coupling block 70, the cable sections 3.50 leading from below from the support body 51 are electrically connected to the cable sections 3.60 leading from above from the feed body 61 via the cable couplings 4, usually an SMA coupling.

[0085] How Figure 1b shows, the individual antennas 2 each consist of a reflector plate 21, which is fastened tightly to the support body 51, and a radiator 22, which may be plate-shaped and is located on the front side 21a of the reflector plate 21 facing away from the support body 51 and at a distance from it.

[0086] For the tight connection, as best Figure 2a shows - one side wall of the support body 51 is removed over such a length that a reflector plate 21 of corresponding length in the axial direction fits onto the U-shaped cross section of the support body 51 then remaining in this area and can be welded tightly to the support body 51 all around.

[0087] This usually happens after the radiator 22, including the coupling piece 15 with the coupling pin 15 protruding therefrom, is fastened to the reflector plate 21 in an opening 5 of the reflector plate 22 - which forms part of the wall of the support body 51 -, wherein the coupling pin 15 on the rear side 22b of the radiator 22 facing the support body 51 contacts the latter at the feed point 23 and introduces the high-frequency oscillation into the radiator 22.

[0088] After welding the reflector plate 21 to the profile of the support body 51, accessibility would be extremely poor.

[0089] Away from the feed point 23, the radiator 22 is screwed via, in this case, two screw connections 24 through spacer sleeves 25, which are arranged between the radiator 22 and the reflector plate 21, at a position at which the radiator 22 oscillating with the applied high frequency has a wave node.

[0090] An angle piece 14c is screwed onto the coupling part 14a of the respective antenna 2, which projects from the rear of the coupling piece 15 and thus transversely to the longitudinal direction 50', to which a cable section 3.50 can be fastened via a coupling part 14b, which runs from there inside the support body 51 to its open end facing the feed body 61.

[0091] Figure 2aIt further shows that the four cable couplings for connecting each 3.50 mm cable section to each 3.60 mm cable section are arranged in a square. Within the passage of the block section.

[0092] Figure 2a further shows the purely mechanical protective device 8 around the antenna unit 1, which here consists of protective rods 9 extending in the axial direction 1' and distributed in a circle around the outside of the antenna unit 1, one of which runs next to the side edge of the reflector plates 21 extending in the longitudinal direction 50' of the antenna part 50.

[0093] The space inside such a pressure vessel 101 is usually very limited, as it contains a number of components that frequently require maintenance and repairs. The protective device 8 prevents damage to the antenna unit 1 by a technician or a moving part in the pressure vessel 101.

[0094] The Figure 4 shows the fastening of the feed body 61 to the wall 101a of the pressure vessel 101 such that the cable sections 3.60 located therein extend through the passage 102 in the wall 101a of the pressure vessel 101, wherein the passage 102 must be large enough to allow the flange 63 at the lower end of the feed body 61 to pass through when inserted from the outside.

[0095] For this purpose, the feed body 61 has, at its end region facing away from the antenna, not only a flange 61b projecting radially outwards from its wall in a ring shape, but also a further flange 61a set back from it.

[0096] Furthermore, at the passage 102, offset outwards from the wall 101a of the pressure vessel 101 by means of a pipe socket 104 at the free end of the pipe socket, there is a radially outwardly projecting, annular flange 103 whose outer diameter corresponds to the diameter of the flange 61a.

[0097] After threading the antenna-side end of the feed body 61 from the outside through the passage 102 in the wall 101a, the flanges 61a and 103 lie axially on one another and can be pressed together radially tightly, for example by a clamping device 80 pressed from the radial outside - if necessary with a seal arranged therebetween.

[0098] These known clamping devices 80 consist of two hinged half-rings, each having a U-shaped cross-section, whereby the free ends of the half-rings can be pressed against each other by a clamping screw. The axial pressing of the flanges against each other is achieved by the conical flanks of the U-shaped cross-section and the similarly conical outer sides of the two flanges to be pressed against each other, facing away from the other flange, which thus become thinner radially outward.

[0099] The flange 61b present at the end of the feed body 61 serves, for example, to be able to tightly attach a flange 65.1 of a tubular extension part 65, be it a straight sleeve or a T-piece as shown in the left half of the figure, through which the cable sections 3.60 can continue to run.

[0100] The continuation part 65 can also be a cover plate closing the front opening of the feed part 61, to or in which the free ends of the cable sections 3.60 are fastened with corresponding plug parts or socket parts. LIST OF REFERENCE SYMBOLS

[0101] 1 Antenna unit 1*Electronic interrogation system. 1 Axial direction 2 Antenna 3 Cable 3.50 Cable section 3.60 Cable section 4 Cable coupling 4a, b Coupling part 4c Intermediate part 5 Breakthrough 6 Spacer sleeve 7 Access opening, threaded opening 8 Protection device 9 Protection rod 10 Vertical 11. in particular horizontal, transverse direction 12. in particular horizontal, transverse direction 13 Coupling piece 14 Cable coupling 14a, b Coupling part 14c Elbow piece 15 Coupling pin 21Reflector plate 21aFront 21bRear 22Radiator 22aFront 22bRear 23Feed point 24Screw connection 25Spacer sleeve 50Antenna part 50'Longitudinal direction 51Support body 51aWall 60Feeder part 61Feeder body 61a, bFlange 62Cable feedthrough 63 64Seal 65Sleeve 65.1Flange 70Flange block 70a, bBlock part 80Clamping device 90Dehumidification unit 91Dehumidification container 100Freeze-drying system 101Pressure vessel 101aWall 102Passage 103Flange 104Pipe socket

Claims

1. Antenna unit (1) comprising - an antenna part (50) comprising a plurality of individual antennas (2), - a feed part (60) for feeding at least one cable (3) comprising a plurality of cable portions (3.50, 3.60) to the antenna part (50) in a protected manner, characterised in that - the antenna part (50) is detachably fastened to the feed part (60) by means of a flange block (70), but in a pressure-tight, i.e. gas-tight, manner, also under a vacuum, relative to the surroundings around the parts (50, 60, 70) of the antenna unit (1), - the cable portion (3.60) of the feed part (60) is fastened to the cable portion (3.50) of the antenna part (50) so as to be easily detachable by means of a cable coupler (4).

2. Antenna unit according to claim 1, characterised in that - the cable (3) is a coaxial cable and / or - the cable coupler (4) is a high-frequency coupler or an SMA coupler, - the antenna-side coupler part (4a) is in particular welded or screwed into the antenna part (50).

3. Antenna unit according to any of the preceding claims, characterised in that the antenna part (50) comprises - a hollow, in particular tubular, carrier body (51), - which in particular consists of metal, preferably stainless steel, - at least one antenna (2), which is fastened to the carrier body (51) and thus closes a cut-out (5) in the wall (51a) of the carrier body (51) in a pressure-tight manner.

4. Antenna unit according to claim 3, characterised in that the part of the antenna (2) fastened to the carrier body (51) consists of the same material as the carrier body (51) and is welded or bonded thereto.

5. Antenna unit according to any of the preceding claims, characterised in that - the antenna part (50) does not comprise a protective casing surrounding the at least one antenna (2) in a leak-tight manner or - the antenna part (50) comprises a protective device surrounding the antenna (2) in a non-leak-tight manner, - which in particular substantially, preferably only, consists of protective rods, for example made of PEEK, arranged around the antenna part (50).

6. Antenna unit according to any of the preceding claims, characterised in that - the antenna (2) comprises a reflector plate (21) and a radiator (22) arranged at a distance therefrom, - in particular, the reflector plate (21) is fastened to, in particular welded to, the carrier body (51) so as to close the cut-out (5) in a leak-tight manner.

7. Antenna unit according to claims 3 and 6 and, if desired, according to claim 4 or 5, characterised in that - at least the reflector plate (21) and / or the radiator (22) and / or the carrier body (51) consist of the same material and in particular consist of the same material as the pressure vessel (101), in particular stainless steel, in particular of the 1.4.4.2004 / AISI 31GL-FDA / GMP or 1.4.4.2004 / AINSI 316L type, and / or - the radiator (22) is detachably fastened to the reflector plate (21).

8. Antenna unit according to claim 6 and, if desired, according to claim 7, characterised in that - a coupler part (14a) of a cable coupler (14), which protrudes from the rear face of the coupling piece (13) into the interior of the carrier body (51), is arranged in a cut-out in the reflector plate (21) or on the rear face (21b) of the reflector plate (21) in front of a cut-out (5) and - the coupler part (14a) is electrically connected to the radiator (22), in particular is fixed, in particular soldered or welded, thereto permanently, i.e. in a manner in which it is not detachable without destroying the connection, via a coupling piece (13) which in particular comprises a coupling pin (15).

9. Antenna unit according to claim 6 and, if desired, according to claim 7 or 8, characterised in that - an access opening (7) is provided in the lower region, in particular at the lowest point, in particular in the lower end wall of the carrier body (51), - which access opening is in particular designed as a threaded opening (7) which can be closed in a leak-tight manner - and is in particular suitable for attaching a gassing device for the purpose of leak testing, for example.

10. Antenna unit according to any of the preceding claims, characterised in that - the flange block (70) comprises two in particular cap-shaped block parts (70a, b) that can be pressed, in particular screwed, against one another in a leak-tight manner and each comprise at least one through-opening for the cable (3), - the free interior space in the flange block (70) is large enough for receiving the at least one cable coupler (4), in particular - at least one of the coupler parts (4a, b, c), in particular a coupler adapter (4c), is fastened, in particular fastened in a leak-tight manner, in particular welded or screwed in a leak-tight manner, in one of the block parts (70a, b) and / or - the two block parts (70a, b) consist of the same material, in particular metal, in particular stainless steel.

11. Antenna unit according to any of the preceding claims, characterised in that the feed part (60) comprises - a tubular feed body (61) which is open on either side and in which the at least one cable (3) extends, - one of the block parts (70b) or a flange (63), which is fastened, in particular welded, in a leak-tight manner to the feed body (61) on the antenna-side end, - a wall feedthrough (62) on the end of the feed body (61) remote from the antenna, which feedthrough is an integral component of the feed body (61) or is connected thereto in an extensively leak-tight manner.

12. Antenna unit according to any of the preceding claims, characterised in that the block part (70b) consists of the same material as the feed body (61).

13. Antenna unit according to any of the preceding claims, characterised in that the feed part (60) is - a straight or curved tube that keeps its shape or - an extensively leak-tight, flexible hose, in particular a corrugated hose, in particular made of stainless steel.

14. Antenna unit according to any of the preceding claims, characterised in that - the antenna part (50) and / or the feed part (60) comprises a dehumidifying unit (90), - in particular, a moisture-absorbing substance such as silica gel is replaceably arranged in a dehumidifying vessel (91), which is connected to the interior space of the part (50, 60) via a leak-tight connection.

15. Antenna unit according to any of the preceding claims, characterised in that - in the fully installed state of the antenna unit (1), the antenna part (50) can be pivoted and fixed about its greatest direction of extension (50') relative to the feed part (60), - in particular by means of a flange block (70) or cable feedthrough (62) designed as a rotating coupler.

16. Freeze-drying system (100) comprising - a temperature-controllable pressure vessel (101), - an electronic controller (100*) arranged outside the pressure vessel (101), - an antenna unit (1) comprising - an antenna part (50) arranged in the pressure vessel (101), - a feed part (60), the feed body (61) of which is equipped with a cable feedthrough (62) from the antenna unit (50) to the controller (100*) or electronic query unit (1*) for the antennas (2) through the wall of the pressure vessel (101), characterised in that the antenna unit (1) is designed according to any of the preceding claims.

17. Freeze-drying system according to claim 16, characterised in that a retaining device is provided in the interior of the pressure vessel (101) for in particular detachably or movably, in particular additionally, fastening the antenna unit (100), in particular its antenna part (50), to the pressure vessel (101).

18. Method for producing an antenna unit (1) comprising an antenna part (50) and a feed part (60) for cables (3) to the antenna part (50) according to claim 3 and, if desired, according to any of claims 4 to 15, characterised in that for producing the antenna part (50), - the cable (3) is introduced into the carrier body (51) of the antenna part (50), - the antenna-side end (3a) of the cable (3) is connected to the antenna (2), in particular its coupling piece (13), so as to project from the cut-out (5), - the antenna (2) is fastened to or in the cut-out (5) in a leak-tight manner as a closure of said opening.

19. Method according to claim 18, characterised in that - the antenna-side end of the cable (3) is detachably connected to the antenna (2), in particular by soldering or welding, by detachable contacting or only by destroying the connection, and / or - the antenna (2), in particular its coupling piece (13), is welded to or in the cut-out (5).

20. Method for installing an antenna unit (1) according to any of claims 1-15 in a pressure vessel (101), in particular a freeze-drying system (100) according to any of claims 16 or 17, characterised in that - the feed part (60) having at least one cable portion (3.60) therein is fastened in the wall passage in the pressure vessel (101) in a leak-tight manner, - the preceding or following antenna part (50) having at least one cable portion (3.50) therein is positioned in the pressure vessel (101) in an intended position and is in particular fixed to a retaining device of the pressure vessel (1), - the feed part (60) and the antenna part (50) are interconnected in a mechanically leak-tight manner and in respect of their cable portions (3.50 and 3.60) via a flange block (70).

21. Method according to claim 20, characterised in that the feed part (60) is inserted into the wall passage (102) in the wall (101a) of the pressure vessel (101) from outside and is fixed in a leak-tight manner against the wall (101a) of the pressure vessel (101).