Connection device for extraction equipment

Abstract

The invention relates to a connection device (10) for an extraction device for vacuum membrane filtration applications, the connection device comprising: a carrier (14) for accommodating a membrane filter or a filter substrate (16); a cavity (30) formed below the membrane filter or the filter substrate (16); a suction channel, the suction channel opens centrally into the cavity (30); and a ventilation channel, the ventilation channel opens laterally into the cavity (30). The connection device (10) also comprises a closing element (18) that can be moved into a plurality of switching positions, the closing element being able to cut off or release the suction channel and the ventilation channel according to the switching position.

Description

Technical Field

[0001] The invention relates to a connection device for a withdrawal device for vacuum membrane filtration applications. Background Art

[0002] In the context of microbiological hygiene studies of aqueous samples, so-called membrane filtration methods are often used, in which a membrane filter with a matching pore size is inserted into a filtration apparatus and the sample is filtered so that the microorganisms contained in the test material are retained on the filter surface by the retention effect of the membrane filter. The contamination present in the liquid medium is usually very small, so that a sample volume of more than 100 ml is usually required for the test.

[0003] In the known vacuum membrane filtration equipment for microbiological research of liquid medium, the filter equipment is composed of a filter substrate, a membrane filter (preferably 47 to 50 mm in diameter) and a funnel for pouring liquid samples. In most applications, the filter equipment is installed on a reusable stainless steel extraction bar, and via the stainless steel extraction bar, negative pressure (hereinafter referred to as vacuum for simplicity) derives the filtrate to a pump. In addition, a culture medium is needed, and the filter contacts the culture medium after filtering. For this reason, culture dishes of different sizes (preferably about 55 millimeters in diameter) are usually used.

[0004] For such sample quantities, the extraction strip, filter substrate and membrane filter remain unchanged, whereas the size of the pouring funnel is usually adapted to the volume of the medium to be examined. Therefore, a system is advantageous in which different versions of the funnel are suitable for the same receptacle or filter substrate.

[0005] Filter bases and pouring funnels are commercially available as stainless steel units, and can also be purchased in the form of structures made of plastic. In the latter case, these are usually commercially available in a pre-sterilized form and are intended for single use. In all processing steps, it is important to maintain the sterility of the auxiliary means used, because otherwise the product and / or the diagnostic result can be distorted.

[0006] In the case of stainless steel designs, the membrane filter must always be inserted individually between the pouring funnel and the filter substrate. To ensure sterility, this is usually done with the aid of heat-sterilized tweezers. The membrane filter is removed again with the aid of re-heat-sterilized tweezers for subsequent inspection.

[0007] There are also various membrane filter devices made of plastic, in which the membrane filter is already inserted and the entire device is available for use in a sterile manner. The task of inserting the membrane filter in the filter device is omitted here.

[0008] As and mentioned, in most applications, the filter device is mounted on a reusable stainless steel extraction strip, via which the vacuum leads the filtrate to the pump. Because the side facing away from the membrane filter is directly connected to the vacuum source and other pipes and containers, these areas are considered to be germicidal. Usually, the side facing away from the filtration is not sterilized before each filtration. This mostly occurs only at the end of the day, for example, at night.

[0009] During vacuum membrane filtration, a vacuum is applied to the side facing away from the filtration, which is not interrupted even after the filtration is finished. As long as there is no ventilation between the membrane filter and the filtrate, the residual liquid cannot flow out. However, a wet membrane filter blocks ventilation.

[0010] It is difficult to remove a wet membrane filter when applying a vacuum, so in various commercially available systems the vacuum is interrupted via a pull-out strip or a pump unit. However, since the vacuum chamber is attached directly below the filter substrate, this causes splashing of residual amounts of filtrate that have not flowed out. In the process, splashed water can cause recontamination.

[0011] In product name A vacuum membrane filtration system with a stainless steel withdrawal strip sold by the applicant is known, which provides connection possibilities for multiple filter stations. Each filter station can be aseptically ventilated via a corresponding connection of the withdrawal strip in order to exclude secondary contamination of the lower side of the filter during ventilation. The vacuum position and the ventilation position can be switched by means of an operating element. In the vacuum position, a suction channel is released, which leads centrally below the horizontally arranged membrane filter. Via the suction channel, the liquid substance contained in the corresponding filter station is sucked through the membrane filter. In the ventilation position, the closing element cuts off the suction channel and simultaneously releases the ventilation channel in such a way that the closing element establishes a fluid connection between a separate ventilation channel and the upper part of the suction channel. The ventilation channel is thus formed by the ventilation channel and the upper part of the suction channel, which leads centrally below the membrane filter.

[0012] Furthermore, vacuum drainage devices for filter devices with a suction channel are known, for example, from EP 1 556 152 B1 and CN 102586082, which lead to a receiving surface of a mechanical support facing the membrane filter in order to suck liquid substances contained in the filter device through the membrane filter. For ventilation, a ventilation channel completely separated from the suction channel is provided, which can be closed and opened by means of a dedicated valve. Summary of the invention

[0013] The object of the present invention is to simplify the ventilation of the area below the membrane filter, which is required to avoid recontamination, in particular by means of a connecting device which is also sufficient without complex valves or electric actuators and can be implemented with the aid of a small number of instrument parts that can be easily installed and removed, easily cleaned and sterilized.

[0014] This object is achieved by a connecting device for a draw-off device for vacuum membrane filtration applications having the features of the invention. Advantageous and expedient embodiments of the connecting device according to the invention are given in this application.

[0015] The connection device for the extraction device according to the invention is provided for vacuum membrane filtration applications and comprises: a carrier for accommodating a membrane filter or a filter substrate; a cavity formed below the membrane filter or the filter substrate; a suction channel, which opens centrally into the cavity; and a ventilation channel, which opens laterally into the cavity. According to the invention, the connection device also comprises a closing element that can be moved into a plurality of switching positions, which, depending on the switching position, can not only cut off or release the suction channel but also the ventilation channel.

[0016] The present invention is based on the following recognition: if the closing element is configured so that it can cut off or release not only the suction channel but also the ventilation channel at the same time in the corresponding switching position independently, that is, independently of other regulating mechanisms, then additional components can be saved in the connecting device. Therefore, additional valves or the like for selectively releasing the ventilation channel can be omitted. The closing element that can be moved to different switching positions can be designed so that when changing the switching position, the suction channel and the ventilation channel are placed in a state corresponding to the switching position (released or cut off) only by the movement of the closing element. Since the additional regulating mechanism for the ventilation channel is omitted, the structure of the connecting device according to the present invention is simplified, and the connecting device is correspondingly low-cost when manufactured.

[0017] The connecting device according to the present invention can reduce the vacuum applied to the suction channel below the membrane filter or achieve pressure balance with the environment during desired ventilation, so that the filtrate will not splash back onto the bottom side of the membrane filter and the residual liquid can be sucked out from below the membrane filter at the same time.

[0018] The ventilation channel should open into the cavity below the membrane filter as far as possible at the top, in order to prevent liquid in the cavity or splashing liquid from being able to enter the ventilation channel as effectively as possible. Accordingly, in a preferred embodiment of the invention, the ventilation channel opens above the collecting section of the cavity. The collecting section should be understood here as the lower area of ​​the cavity below the membrane filter, in which (residual) liquid is present during or after the filtration process. That is to say, the opening of the ventilation section is above the liquid level of the (residual) liquid, as can usually be found during or after filtration.

[0019] Preferably, in the connection device according to the invention, the ventilation channel is separated from the suction channel in each switching position, that is to say there is no direct fluid connection between the ventilation channel and the suction channel - unlike, for example, in The situation in vacuum membrane filter systems. The continuous separation allows the suction channel and the ventilation channel to be designed according to the respective requirements without having to make any compromises. However, the decisive advantage is that the suction channel and the pressure channel can be released or cut off independently of each other by the closing element. This makes it possible in particular to achieve the desired switching position for pressure balance below the membrane filter while extracting residual liquid, in which the suction channel and the pressure channel are both released.

[0020] In a preferred embodiment of the invention, the closing element has at least one suction channel section for completing the suction channel in at least one switching position and at least one ventilation channel section for completing the ventilation channel in at least one switching position. By appropriate movement of the switching element, these channel sections can be brought into a position such that the suction channel or the ventilation channel or both are completed and thus released.

[0021] The connecting device according to the invention has at least two, ideally three different switching positions:

[0022] In the first switching position, the suction channel is released and the ventilation channel is blocked. This corresponds to the "vacuum" position, in which filtering operation is carried out and simultaneous ventilation is not desired.

[0023] In the second switching position, not only the suction channel but also the ventilation channel is released. This corresponds to the "ventilation" position, in which the vacuum that continues to be applied to the suction channel after the filtration is completed ensures that the residual liquid is sucked out without causing splashing.

[0024] In the first switching position, the suction channel is blocked and the ventilation channel is released. This corresponds to a "stop" position in which no filtering operation is performed, but ventilation is meaningful or desired in order to easily remove the membrane filter or filter substrate from the carrier.

[0025] The above-mentioned switching positions with regard to the suction channel can be realized most simply by forming two suction channel sections in the closing element, one of which completes the suction channel in the first switching position (“vacuum”) and the other completes the suction channel in the second switching position (“ventilation”).

[0026] With regard to the ventilation channel, the switching position can be realized most simply by forming two ventilation channel sections in the closing element, one of which completes the ventilation channel in the second switching position (“ventilation”) and the other completes the ventilation channel in the third switching position (“stop”).

[0027] Particularly preferred is an embodiment of the invention in which the closing element is rotatably mounted in a body of the connection device, into which the carrier is also inserted. The rotation of the closing element into different switching positions, if necessary by means of an operating element acting on the closing element, is a switching movement that can be performed easily and intuitively for the operator. However, in addition to the rotatable mounting of the closing element, the body also fulfills another function in this embodiment in that it serves as a receptacle for the carrier of the connection device.

[0028] The body of the connecting device, into which the carrier is inserted, is preferably made of stainless steel or aluminum and is connected securely or releasably to the withdrawal device, which is usually also made of stainless steel or aluminum.

[0029] The closing element is preferably releasably supported in the body. Since the closing element can wear due to its movement and contact with the medium, it is expedient to design it as a replacement part.

[0030] In the above-described construction of the connecting device, in which the connecting device has a body in which the closing element is rotatably supported and the connecting device has a carrier that is firmly, but also releasably inserted into the body, it is necessary that the ventilation channel has a ventilation channel section located in the body and a ventilation channel section located in the carrier. The body and the carrier are usually designed to be essentially rotationally symmetrical. In order to avoid having to forcibly insert the carrier into a specific rotational position relative to the body in order to align the ventilation channel sections with each other, in a preferred embodiment, a sealed cavity is provided that is formed essentially annularly between the body and the carrier. The cavity, which is sealed, for example, by means of an O-ring, ensures a fluid connection between the ventilation channel section of the body and the ventilation channel section of the carrier in any case, regardless of the rotational position.

[0031] In particular, with regard to simplified handling, it is expedient to configure the connecting device as a separating valve which has a closing element in the form of a plug (conical segment).

[0032] According to the present invention, different switching positions are realized by the closing element moving into the corresponding position. Therefore, advantageously, the closing element is mechanically coupled to the operating element so that switching between the switching positions is possible without problems for the user.

[0033] Preferably, the connecting device according to the invention is provided with a locking mechanism for the closing element, which holds the closing element in a defined manner in the respective switching position.

[0034] In order to exclude contamination of the underside of the membrane filter during ventilation, a sterile air filter is connected upstream of the ventilation channel of the connecting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Other features and advantages of the present invention are apparent from the following description and the accompanying drawings to which reference is made. In the accompanying drawings:

[0036] Figure 1a and 1b A lateral exterior view and a lateral sectional view rotated through 90° show the connecting device according to the invention for a pull-out device in a first switching position (“vacuum”);

[0037] Figure 2a and 2b A lateral exterior view and a lateral sectional view rotated through 90° showing the connecting device according to the invention in a second switching position (“ventilation”); and

[0038] Figure 3a and 3bThe connecting device according to the invention is shown in a lateral exterior view and in a lateral sectional view rotated through 90° in the third switching position (“stop”). DETAILED DESCRIPTION

[0039] exist Figure 1a and 1b 1 shows a connection device 10 made of stainless steel for a withdrawal device which is provided for vacuum membrane filtration applications.

[0040] The connection device 10 comprises an elongated body 12 into which a carrier 14 is inserted. In the inserted state, the carrier 14 is firmly and tightly connected to the body 12, but can also be removed from the body 12 again. This is important with regard to the possibility of cleaning the connection device 10 and inserting different carriers 14 into the body 12.

[0041] The filter substrate 16 is placed on the carrier 14. For vacuum membrane filtration, a pouring funnel is mounted on the filter substrate 16, wherein a membrane filter is then clamped between the filter substrate 16 and the funnel.

[0042] A closing element 18 is rotatably mounted in the body 12 below the carrier 14, wherein the longitudinal axes of the body 12 and the carrier 14 extend concentrically and perpendicularly to the horizontal rotation axis of the closing element 18. The closing element 18 is designed as a truncated cone-shaped plug and is part of the isolating valve. Different channel sections are formed in the closing element 18, which will be described in more detail later when explaining the operating principle. The isolating valve also includes an operating element 20 that acts on the closing element 18 outside the body 12 and is used to manually operate the closing element 18.

[0043] The closing element 18 can be rotated into at least two switching positions, in the illustrated embodiment three different, stable switching positions, by means of an operating element 20. For this purpose, a locking mechanism is provided which has a locking element 22 arranged in the body 12 and prestressed toward the closing element 18. The locking element 22 can engage in a known manner in respective locking recesses 24 which are formed in the closing element 18 and define the respective switching positions.

[0044] In the body 12 and in the carrier 14 on both sides of the closing element 18, a central suction channel section 26 or 28 is formed, which forms the main part of the suction channel. The first suction channel section 26 in the body 12 opens into the extraction channel of the stainless steel extraction strip (not shown) on the side facing away from the closing element 18. The second suction channel section 28 in the carrier 14 opens centrally on the side facing away from the closing element 18 into a cavity 30, which is located below the filter substrate 16 to be inserted. The lower section of this cavity 30 is called the collecting section 30a, in which (residual) liquid will be present during or after the filtering process.

[0045] Independently of the suction channel sections 26, 28, a ventilation channel section 32 or 34 is formed in the body 12 and in the carrier 14, which is fluidically connected to each other and forms part of the ventilation channel. The fluid connection between the two ventilation channel sections 32 and 34 can be established in the following way: the ventilation channel sections have openings that are opposite to each other and aligned with each other, but this is premised on a specific rotational position of the carrier 14 relative to the body 12. Therefore, in the embodiment shown, a substantially annularly surrounding cavity 36 is provided between the body 12 and the carrier 14, into which the openings of the ventilation channel section 32 formed in the body 12 and the openings of the ventilation channel section 34 formed in the carrier 14 respectively lead. The cavity 35 is sealed, in the embodiment shown, by two O-rings 38 arranged between the body 12 and the carrier 14 at different axial heights. Due to the surrounding cavity 36 , a fluid connection between the two ventilation duct sections 32 and 34 is always ensured, regardless of the rotational position of the carrier 14 relative to the body 12 .

[0046] The end of the upper ventilation channel section 34 in the carrier 14 facing away from the lower ventilation channel section 32 opens laterally into the cavity 30 located below the filter substrate 16 to be inserted. The opening 34a is arranged above the collecting section 30a of the cavity 30 at an axial height which - under normal circumstances - is higher than the level of the (residual) liquid present in the cavity 30 during or after filtration.

[0047] The lower ventilation channel section 32 in the body 12 leads to a side surface of the closing element 18 .

[0048] The ventilation channel also includes a sterile air filter 40 arranged laterally on the body 12 in the extension of the rotation axis of the closing element 18. The sterile air filter 40 has an inlet 42 in contact with the surroundings and an outlet 44 facing the end face of the closing element 18 facing away from the operating element 20.

[0049] According to an alternative embodiment not shown, the sterile air filter 40 can also be arranged laterally on the other side of the body 12. In this case, the outlet 44 of the sterile air filter 40 faces the side wall of the body 12. The sterile air filter 40 can be, for example, about Figure 1b The vertical center axis in the view of FIG. 4 is offset by 90°, so that the flow path through the sterile air filter 40 does not extend in the paper plane but extends perpendicular to the paper plane.

[0050] Next, according to Figure 1a , 1b The three switching positions shown in FIGS. 2 a , 2 b and 3 a , 3 b explain the operating principle of the connecting device 10 .

[0051] Figure 1a and 1b The connecting device 10 is shown in a first switching position, which is referred to below as "vacuum". The switching position "vacuum" corresponds to the normal operation of the connecting device 10 when the medium contained in the inserted filter substrate 16 is to be sucked through the membrane filter. Accordingly, the suction channel is released in this switching position, which is indicated by the uninterrupted arrow A, which indicates the suction direction. The suction channel is released in the switching position "vacuum" because the third suction channel section 46 in the closing element 18 connects the first suction channel section 26 in the body 12 to the second suction channel section 28 in the carrier 14.

[0052] The ventilation channel is cut off by the closing element 18 in the "vacuum" position, as will be explained below. The outlet 44 of the sterile air filter 40 toward the closing element 18 leads into the horizontal third ventilation channel section 48 in the closing element 18. The third ventilation channel section 48 extends along the rotation axis of the closing element 18, so that the third ventilation channel section is always connected to the outlet 44 of the sterile air filter 40 regardless of the rotation position of the closing element 18. However, in the "vacuum" position, there is no fluid connection between the ventilation channel section branched from the third ventilation channel section 48 and the second ventilation channel section 32 in the body 12 in the closing element 18. As a result, air from the surrounding environment cannot enter the part of the ventilation channel that leads into the cavity 30. This is characterized by the crossbar in the closing element 18, which interrupts the arrow B.

[0053] In the case where the sterile air filter 40 is alternatively arranged laterally on the body 12, which is not shown, the third ventilation channel section 48 is not formed in the closing element 18 but in the body 12, so that the outlet 44 of the sterile air filter 40 leads to the inlet of the third ventilation channel section 48. However, in the "vacuum" position, as described above, the ventilation channel section formed in the closing element 18 and the second ventilation channel section 32 in the body 12 are not fluidically connected, so that the ventilation channel is blocked.

[0054] From the "vacuum" position, the closing element 18 can be rotated counterclockwise by means of the operating element 20 into the switching position "vent". Figure 2a and 2b In this switching position, both the suction channel and the ventilation channel are released, as will be explained below.

[0055] In the switching position “ventilation”, the fourth suction channel section 50 in the closing element 18 connects the first suction channel section 26 in the body 12 with the second suction channel section 28 in the carrier 14, so that the suction channel is released according to the uninterrupted arrow A. (The fourth suction channel section 50 is Figure 1b 1 ). Not visible in the view of FIG. 1 due to the different rotational positions of the closing element 18 .

[0056] At the same time, in the closing element 18, another fourth ventilation channel section 52 vertically branched from the third ventilation channel section 48 establishes a fluid connection between the third ventilation channel section 48 and the second ventilation channel section 32 in the body 12. (The fourth ventilation channel section 52 is Figure 1b 1 ). Not visible in the view of FIG. 1 due to the different rotational positions of the closing element 18 .

[0057] In the alternative case of a laterally arranged sterile air filter 40 on the body 12 , not shown, the fourth ventilation duct section 52 in the closing element 18 establishes a fluid connection between the third ventilation duct section 48 in the body 12 and the second ventilation duct section 32 in the body 12 .

[0058] Thus, according to the uninterrupted arrow B, air from the surroundings can enter laterally into the cavity 30 via the four ventilation duct sections 48 , 52 , 32 , 34 after passing through the sterile air filter 40 .

[0059] The “venting” switch position ensures that residual liquid can be safely removed after filtration while the vacuum is still being applied, without the risk of recontamination.

[0060] In order to finally facilitate the removal of the wetted membrane filter, the closing element 18 is rotated clockwise from the switching position "ventilation" into the position "stop" by means of the operating element 20. Figure 3a and 3b In the switching position shown in FIG. 1 , the suction channel is interrupted by the closing element 18, since neither the third suction channel section 46 nor the fourth suction channel section 50 establishes a fluid connection between the first suction channel section 26 in the body 12 and the second suction channel section 28 in the carrier 14. This is indicated by two crosspieces, which interrupt the arrow A. That is, the vacuum of the extraction device, which is still applied to the lower access opening of the first suction channel section 26, has no effect on the membrane filter on the filter substrate 16.

[0061] In the “stop” switching position, however, the ventilation channel continues to be released since the fifth ventilation channel section 54 branching off from the third ventilation channel section 48 in the closing element 18 is fluidically connected to the second ventilation channel section 32 in the body 12 .

[0062] In the alternative case of a laterally arranged sterile air filter 40 on the body 12 , not shown, the third ventilation duct section 48 formed in the body 12 is fluidically connected to the second ventilation duct section 32 in the body 12 via a fifth ventilation duct section 54 in the closing element 18 .

[0063] Thus, according to the uninterrupted arrow B, air from the surroundings can enter laterally into the cavity 30 via the four ventilation duct sections 48 , 54 , 32 , 34 after passing through the sterile air filter 40 .

[0064] Since ventilation is thereby ensured below the membrane filter on the one hand and the vacuum of the extraction device which is still applied on the other hand has no suction force on the membrane filter, the membrane filter can be removed from the filter substrate 16 without any problems in the “parking” position.

[0065] It should be noted that the three switching positions of the connecting device 10 are reached simply by rotating the closing element 18, without the need for additional valves etc. All fluid connections or fluid interruptions in the suction channel and ventilation channel required for the corresponding operating mode are established by appropriately arranging the channel sections in the rotatable closing element 18.

[0066] Reference numerals list

[0067] 10Connection device

[0068] 12 Body

[0069] 14 bearing parts

[0070] 16 Filter substrate

[0071] 18. Close the element

[0072] 20 operating elements

[0073] 22 Locking element

[0074] 24 locking grooves

[0075] 26 First suction channel section in body

[0076] 28 Second suction channel section in the carrier

[0077] 30 Cavity

[0078] 30a Collection section of cavity

[0079] 32 Second ventilation channel section in body

[0080] 34 First ventilation channel section in the carrier

[0081] 34a: opening of the first ventilation channel section

[0082] 36 Cavity

[0083] 38O-ring

[0084] 40 Air Sterile Filter

[0085] 42 Air sterile filter inlet

[0086] 44 Air sterile filter outlet

[0087] 46 Third suction channel section in closing element

[0088] 48 Closing element or third ventilation channel section in the body

[0089] 50 Fourth suction channel section in closing element

[0090] 52 Closing element fourth ventilation channel section

[0091] 54 Fifth ventilation channel section in closing element

[0092] A Suction direction

[0093] B Ventilation direction

Claims

1. A connection device (10) for a draw-off device for vacuum membrane filtration applications, comprising: a carrier (14) for accommodating a membrane filter or a filter substrate (16), a first cavity formed below the membrane filter or the filter substrate (16), a suction channel which opens centrally into the first cavity, and a ventilation channel, the ventilation channel opening laterally into the first cavity, It is characterized in that A closing element (18) is provided which can be moved into a plurality of switching positions and can block or release the suction channel and the ventilation channel depending on the switching position, wherein the ventilation channel is separated from the suction channel in each switching position.

2. The connecting device (10) according to claim 1, characterized in that: The ventilation channel opens into the first cavity above a collecting section (30a) of the first cavity.

3. The connecting device (10) according to claim 1 or 2, characterized in that: The closing element (18) has at least one suction channel section for completing the suction channel in at least one switching position, and the closing element has at least one ventilation channel section for completing the ventilation channel in at least one switching position.

4. The connecting device (10) according to claim 1 or 2, characterized in that: In a first switching position, the intake channel is released and the ventilation channel is blocked.

5. The connection device (10) according to claim 4, characterized in that: In a second switching position, both the suction channel and the ventilation channel are released.

6. The connection device (10) according to claim 5, characterized in that In a third switching position, the intake channel is blocked and the ventilation channel is released.

7. The connection device (10) according to claim 6, characterized in that Two suction channel sections are formed in the closing element (18), wherein one suction channel section completes the suction channel in a first switching position and the other suction channel section completes the suction channel in a second switching position.

8. The connecting device (10) according to claim 6 or 7, characterized in that: Two ventilation channel sections are formed in the closing element (18), wherein one ventilation channel section completes the ventilation channel in a first switching position and the other ventilation channel section completes the ventilation channel in a third switching position.

9. The connecting device (10) according to claim 1 or 2, characterized in that: The closing element (18) is rotatably mounted in a body (12) of the connecting device (10), in which the support (14) is also inserted.

10. The connection device (10) according to claim 9, characterized in that At least the body (12) is made of stainless steel or aluminum and is securely or releasably connected to the extraction device.

11. The connection device (10) according to claim 9, characterized in that The closing element (18) is releasably mounted in the body (12).

12. The connection device (10) according to claim 9, characterized in that The ventilation channel comprises a ventilation channel section in the body (12) and a ventilation channel section in the carrier (14), the ventilation channel section in the body and the ventilation channel section in the carrier being fluidically connected to each other via a sealed second cavity formed annularly between the body (12) and the carrier (14).

13. The connection device (10) according to claim 1 or 2, characterized in that: The closing element (18) is a plug of an isolating valve.

14. The connection device (10) according to claim 1 or 2, characterized in that: The closing element (18) is mechanically coupled to an operating element (20).

15. The connection device (10) according to claim 1 or 2, characterized in that: A locking mechanism is provided, by means of which the closing element (18) is held in the respective switching position.

16. The connection device (10) according to claim 1 or 2, characterized in that: An air sterile filter (40) is connected upstream of the ventilation channel.

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