REPLACEABLE BREATHING GAS FILTER

Description

[0001] The present invention relates to a respiratory gas filter arrangement according to the preamble of claim 1.

[0002] The respiratory gas filter arrangement of the present invention is intended for use in a ventilation line designed to guide inspiratory and / or expiratory respiratory gas during at least partial artificial ventilation of a patient, wherein the ventilation line defines a virtual respiratory gas flow path centrally permeating it, along which the ventilation line guides the respiratory gas, wherein the ventilation line has a filter carrier in which a filter receiving chamber is formed through which the respiratory gas flow path is permeated, and in which a respiratory gas filter through which the respiratory gas flows can be exchangeably received.

[0003] Such a ventilation line is known from WO 2013 / 127474 A1. Ventilation lines for conveying inspiratory and / or expiratory respiratory gases are used on ventilation devices for at least the supportive artificial ventilation of human or animal patients, in order to convey inspiratory respiratory gases from a respiratory gas source to the patient and / or to convey expiratory respiratory gases away from the patient.

[0004] Sometimes, respiratory gas filters are installed in the ducting of the ventilation line to remove, for example, particles and / or droplets that are harmful or unwanted to the patient from the inspiratory respiratory gas, or to remove pathogens exhaled by the patient from the expiratory respiratory gas.

[0005] Since a breathing gas filter, once used, naturally has a limited lifespan and must then be replaced by a fresh or at least less heavily used breathing gas filter, a filter holder is provided on the known ventilation line, which allows a used breathing gas filter to be replaced by an unused breathing gas filter.

[0006] A disadvantage of the conventional ventilation line is that the flow of breathing gas must be interrupted to change the breathing gas filter, as the line must be physically opened or disconnected for this purpose. Therefore, artificial ventilation is not possible during a filter change.

[0007] US 3 556 097 and GB 1 294 307 A also describe a ventilation line with a replaceable breathing gas filter, in each of which the breathing gas flow must be interrupted for filter replacement.

[0008] From DE 42 16 343 C2, a method and a device for removing a vehicle air conditioning filter are known. When removing the known vehicle air conditioning filter, it is pulled directly from the air conditioning duct into a bag that contains it, preventing the release of dirt from the used filter into its surroundings. To ensure the best possible seal at the point where the vehicle air conditioning filter is removed from the air conditioning duct, the known bag has a sealing cord with which the elastic bag can be connected to a removal opening in the air conditioning duct.

[0009] German patent application GB 11577995 A discloses a filter housing with multiple filter elements. In this filter housing, a new filter element is inserted from one side of a polyethylene bag through a side opening in the housing. Simultaneously, a used filter element is inserted from the opposite side of the housing into a polyethylene bag and disposed of. The polyethylene bags are sealed to flanges surrounding the respective side openings of the filter housing via specially designed polyethylene stubs, which are referred to as "polyethylene stubs" in GB 11577995 A.

[0010] A disadvantage of the latter two known filter arrangements is the undesirably large effort required to connect a shape-insensitive bag with an opening in a filter housing in order to load an unused filter contained in the bag into the filter housing and / or to load a used filter into a bag.

[0011] The object of the present invention is to improve the aforementioned respiratory gas filter arrangement in such a way that it allows the respiratory gas filter to be changed without interrupting the flow of respiratory gas in the ventilation line.

[0012] This problem is solved according to the invention by a breathing gas filter arrangement with all the features of claim 1.

[0013] The breathing gas filter arrangement is intended for use on a ventilation line, as mentioned above, in which the filter carrier has a wall surrounding the filter receiving chamber at a radial distance from the virtual breathing gas flow path, with an insertion opening arranged at a radial distance from the virtual breathing gas flow path, through which the breathing gas filter can be inserted into the filter receiving chamber and brought into its operational position.

[0014] While in the ventilation line of WO 2013 / 127474 A1 an insertion opening is only created by separating two ventilation line sections in the area of ​​the filter receiving chamber, whereby the insertion opening is penetrated by the virtual breathing gas flow path, i.e., is arranged without radial distance to the virtual breathing gas flow path, in the ventilation line of the present application the insertion opening located radially away from the virtual breathing gas flow path can exist permanently regardless of the operating state of the other components of the ventilation line or even the ventilation device, so that a breathing gas filter can be inserted into the filter receiving chamber at any time.

[0015] With the insertion movement, the breathing gas filter can be brought close to the virtual breathing gas flow path from the insertion opening and thus positioned within the breathing gas flow of the ventilation line, allowing it to flow through the gas. In the operational position, the virtual breathing gas flow path passes through the breathing gas filter, so that the breathing gas flow encounters the breathing gas filter in the area of ​​the filter chamber and flows through it, utilizing its filtering effect.

[0016] No modification of the filter housing or the wall surrounding the filter housing is necessary for inserting the breathing gas filter into the filter housing. Therefore, ventilation operation, in which the ventilation line is involved at that time, can be maintained even while the breathing gas filter is being inserted into its operating position within the filter housing.

[0017] Although the breathing gas flows unfiltered in the ventilation line between the time a used breathing gas filter is removed and the time a new one is placed in its operating position, this is a far lesser disadvantage compared to a complete interruption of artificial ventilation.

[0018] In principle, it can be assumed that the breathing gas filter can simply be inserted into the filter housing and into the operating position through the insertion opening by the operator. However, for the fastest, safest, and most precise filter change possible, with minimal interruption of only the filter's effectiveness and not of artificial ventilation itself, it is particularly advantageous if the filter holder has a guide structure that directs the breathing gas filter from the insertion opening into the filter housing. Thus, it may be sufficient for the operator to simply position a new breathing gas filter correctly at the insertion opening and roughly guide it in the right direction. The guide structure on the filter holder then ensures that the new breathing gas filter executes the desired movement into the filter housing correctly.Preferably, the guide structure not only ensures arbitrary movement of the breathing gas filter into the filter receiving chamber, but in a preferred embodiment of the present invention ensures movement guidance of the breathing gas filter in its operating position.

[0019] The guide structure can be formed by a channel penetrating the filter carrier, preferably formed by wall sections of the filter carrier surrounding the filter receiving chamber. In a less preferred embodiment, due to its complexity, the filter carrier can also have at least one guide rail and / or guide groove, which form the guide structure.

[0020] Preferably, the achievement of the operating position of the breathing gas filter is perceptible to an operator, particularly one who manually drives the breathing gas filter into the filter housing, for example by a haptic and / or acoustic and / or visual signal. The haptic and / or acoustic signal can be achieved by the breathing gas filter locking into the operating position. Therefore, preferably at least one locking element is arranged in the filter housing, particularly on the guide structure, which interacts with a counter-locking element on the filter side to lock the breathing gas filter into the operating position.

[0021] An optical signal can be achieved by appropriate color and / or shape design of the breathing gas filter, for example by having a color and / or shape boundary on the breathing gas filter assume a predetermined relative position relative to a reference section in the area of ​​the filter receiving space, especially in the area of ​​the insertion opening, such as an edge of the insertion opening, which characterizes the achievement of the operating position.

[0022] When the present application refers to a "new" breathing gas filter, this does not necessarily mean a brand-new breathing gas filter, although this will usually be the case. A "new" breathing gas filter is any breathing gas filter that is the first breathing gas filter to be introduced into the filter chamber or that is intended to replace a more heavily used breathing gas filter in the filter chamber.

[0023] In principle, it is conceivable that a used breathing gas filter could be removed from the filter housing by reversing the insertion motion through the insertion opening. However, this is not advantageous due to the existing risk of contamination. This is because a potentially contaminated used breathing gas filter is moved through an insertion opening through which a clean, new filter is subsequently to be inserted into the filter housing. This risk of contamination can be reduced by having the filter holder wall feature a removal opening, located radially away from the virtual breathing gas flow path and separate from the insertion opening, through which a breathing gas filter located in the filter housing can be removed.Thus, the removal of a breathing gas filter from the filter chamber can advantageously be carried out through a different opening than the insertion of a breathing gas filter into the filter chamber.

[0024] Removing a used breathing gas filter, which is often only accessible with a potentially very small amount of physical force at the start of the removal process, can be facilitated by positioning the guide structure between the insertion and removal openings. This allows the guide structure to also guide the removal of the breathing gas filter from the filter housing. This enables particularly convenient operation, whereby a used breathing gas filter can be displaced from the filter housing by the new breathing gas filter. Upon insertion of the new breathing gas filter, the used breathing gas filter can be pushed out of the filter housing by the new filter.

[0025] For this purpose, the new breathing gas filter preferably has a reinforcing feature, such as a reinforcing edge rib, at least at its end area which is ahead in the insertion direction, in order to exert sufficient force on the used breathing gas filter located in the filter receiving area to displace it.

[0026] Since identical breathing gas filters are preferably used sequentially to avoid errors during ventilation, the breathing gas filter also has a reinforcing feature, such as a reinforcing rim, at its trailing end in the insertion direction, in order to withstand the displacing force of the new breathing gas filter during its insertion. The aim of the force transmission between the new and unused breathing gas filters is not to deform at least one of the two filters, but rather to facilitate their desired movement. Therefore, a breathing gas filter preferably has a filter material, particularly a flat filter material, through which breathing gas can flow, and which is surrounded by a frame that is rigid compared to the filter material. The frame preferably has a central through-opening as a circumferential frame, through which the breathing gas flows during ventilation through the filter material surrounded by the frame.

[0027] While complex movement paths for inserting and / or removing a breathing gas filter are conceivable in principle, or even advantageous to prevent unwanted removal of a breathing gas filter from its operating position, complex movement paths can require high displacement forces to effect the desired movement. Filter replacement can then be performed with advantageously low displacement forces if the breathing gas filter can be moved along a kink-free guide path defined by the guide structure, through the insertion opening, towards the virtual breathing gas flow path, into the filter housing and into the operating position, and from the operating position, away from the virtual breathing gas flow path, out of the filter housing and through the removal opening. Preferably, this kink-free guide path is a straight path.Then the insertion opening and extraction opening can be formed on opposite sides of the wall of the filter receiving chamber along the guide path.

[0028] To reduce the aforementioned risk of contamination, the filter holder can be designed to allow movement of a breathing gas filter into and out of the filter receiving chamber in only one direction.

[0029] This applies in particular to the guide structure, which allows for particularly effective control of the movement of the breathing gas filter into and out of the filter holder. For this purpose, the filter holder, and especially the guide structure on the filter holder, can have a locking mechanism that permits movement of the breathing gas filter through the insertion opening into the filter chamber and inhibits movement of the breathing gas filter in the opposite direction through the insertion opening. The locking mechanism can be designed in the form of a latching or detent mechanism.

[0030] In principle, the inhibiting element can generate the aforementioned inhibiting effect by acting directly on porous filter material or a correspondingly deformable frame material of the aforementioned frame. For example, a toothed design inclined in the direction of the permitted movement can be provided on the filter carrier or on the guide structure as an inhibiting element, so that the filter or frame material slides under the toothed design when moving in the permitted direction of movement, and the toothed design penetrates the filter or frame material when an attempt is made to move the breathing gas filter in the inhibited direction of movement.

[0031] Particularly reliable unidirectional movement inhibition can be achieved by providing the breathing gas filter with a counter-formation that interacts with the inhibition formation of the filter carrier to enable unidirectional movement of the breathing gas filter. Preferably, the counter-formation interacts with the inhibition formation in a form-fitting manner. Furthermore, by forming a counter-formation that interacts with the inhibition formation provided on the filter carrier or guide structure, the risk of inserting the wrong breathing gas filter into a filter carrier can be significantly reduced. If the counter-formation is not present or deviates from the original design, the insertion of an incorrect new breathing gas filter will be immediately noticeable to the operator.

[0032] In a particularly effective and therefore preferred embodiment, the locking formation and the locking counter-formation constitute a plurality of unidirectionally overcomeable detents arranged one behind the other along the permitted direction of movement. For example, the locking formation and the locking counter-formation can each have a sawtooth formation made of sufficiently elastic material and extending along the guide track. The inclined surfaces of the two sawtooth formations that are less steeply inclined with respect to the guide track or the direction of movement can slide past each other in one direction, while in the opposite direction, the inclined surfaces of the two sawtooth formations that are more steeply inclined with respect to the guide track and the direction of movement form a physical barrier to movement that cannot be overcome without damage.

[0033] The aforementioned reinforcing features, in particular the rims, and especially preferably the surrounding frame, are, or preferably are, gas-impermeable, so that the breathing gas filter provides a defined opening for the flow of breathing gas. Preferably, the aforementioned frame or a reinforcing rim of the breathing gas filter, in the operating position of the breathing gas filter, serves to seal the inlet opening. More preferably, the aforementioned frame or a reinforcing rim of the breathing gas filter, in the operating position of the breathing gas filter, also serves to seal the outlet opening. Thus, simply by arranging the breathing gas filter in its operating position within the filter carrier or filter chamber, it can be ensured that the filter chamber through which the breathing gas flows is separated from the ambient atmosphere surrounding the filter carrier during ventilation.According to a preferred embodiment of the present disclosure, a sealing lip or, more generally, another sealing formation can be provided at the edge of the inlet opening and / or the outlet opening, which, in the operating position of the breathing gas filter, abuts the reinforcing edge or the frame of the breathing gas filter in a sealing manner. As described in this section, the frame or at least the edge can form a flow barrier against unwanted flow of breathing gas through the inlet opening and / or the outlet opening. For this to be effective, however, the edge or frame forming the flow barrier must be gas-impermeable.

[0034] The wall having the inlet opening and / or the outlet opening can be part of a housing of the filter holder that surrounds the filter receiving chamber in its operational state. For cleaning and / or maintenance purposes, the housing can be designed as a divisible housing with at least two housing parts that can be removed from one another and brought close together. It is therefore not excluded that the housing of the filter holder can be disassembled into at least two parts. According to the disclosure, however, such disassembly should not be necessary for changing the breathing gas filter.

[0035] Fundamentally, the filter holder must be permeable to breathing gas. For this purpose, the filter holder can have flow-carrying sections on both sides of the filter chamber, such as connection points for attaching a breathing tube. It is often desirable to be able to influence the temperature of the breathing gas filter in its operating position, in particular to be able to heat the breathing gas filter in its operating position. For the installation of a filter heater on the filter holder, aligned sections of pipe on both sides of the filter chamber can be disadvantageous, as they can restrict the heating surface of a heating device that can be detachably mounted on the filter holder.To achieve the largest possible heating surface while simultaneously allowing the filter carrier to be separated from a heating device supplying the heating power, it is advantageous if the filter carrier has flow-carrying conduit sections on both sides of the filter receiving chamber, the respective sections of which of the associated virtual breathing gas flow path enclose an angle with each other.

[0036] To influence the temperature of the breathing gas filter, the ventilation line can have a filter heater as the heating device mentioned above, which surrounds the filter holder at least partially in the operational state.

[0037] To enable the filter holder to be removed from the filter heater for repair and / or maintenance, the filter heater can have a filter holder receptacle designed as a separate component from the filter holder. The filter holder can be inserted into this receptacle and removed from it. The filter holder can be removed from the filter heater without interrupting the breathing gas flow or opening the ventilation line. Filter replacement can even be carried out when the filter holder is inserted in the filter holder receptacle of the filter heater if, according to an advantageous embodiment of the present disclosure, the filter heater has a wall with a through-opening which, in the operational state, is aligned with the insertion opening such that a breathing gas filter can be inserted through the through-opening into the insertion opening and thus into the filter holder.The same applies, mutatis mutandis, to the extraction opening. According to this advantageous further development, one wall of the filter heater should therefore have a through-opening which, in the operational state, is aligned with the extraction opening.

[0038] In principle, the breathing gas filter can be stored and brought to the filter holder in any manner until it is used. According to the invention, the breathing gas filter is packaged until shortly before its insertion into the filter housing to protect it from external influences, in particular from contamination. As already explained above, the breathing gas filter can be inserted into the filter housing along an insertion path. The insertion path is preferably the guide path defined by the guide structure mentioned above. To protect it from external influences, the breathing gas filter is, according to the invention, contained in a casing in an initial state before its insertion into the filter housing, the casing being further preferably designed to facilitate the insertion of the breathing gas filter into the filter housing.

[0039] To protect the breathing gas filter from external influences not only during storage and transport, but also to enable its insertion into the filter housing under the most hygienic conditions possible, the casing, according to the invention, features a coupling formation. Likewise, either the filter carrier or the filter heater, depending on whether the new breathing gas filter is inserted directly into the filter housing through the insertion opening of the filter carrier or first through a passage opening of a filter heater, features a coupling counter-formation that can be coupled to the coupling formation.

[0040] According to a preferred embodiment of the present disclosure, the coupling formation can be coupled to the coupling counter-formation of the filter carrier or the filter heater in such a way that, in a transfer state in which an access opening of the casing, designed for dispensing the breathing gas filter from the casing, is aligned with the insertion opening along the insertion path, the casing is held against the coupling counter-formation. Thus, not only can the casing with the new breathing gas filter be temporarily positioned on the filter carrier or the filter heater without requiring continuous holding, but the casing can also cover the insertion opening and, optionally, the passage opening, at least in the transfer state, through the interaction of the coupling formation and the coupling counter-formation.This also protects the filter chamber from external influences, such as contamination, by means of the sleeve, which is coupled to the filter holder or filter heater via its coupling configuration. When the sleeve is coupled to the counter-coupling configuration via its coupling configuration, the filter holder can be easily moved without the sleeve detaching from the filter holder or filter heater. This significantly simplifies filter replacement.

[0041] Since, in the transfer state, the access opening of the casing aligns with the insertion opening and, if applicable, also with the through-opening along the insertion path, the new breathing gas filter, still located within the casing, can be moved from the casing into the filter receiving chamber particularly easily through the aforementioned at least one opening. According to the invention, this can be done with particular hygienic advantage without personnel touching the breathing gas filter or allowing the breathing gas filter to come into contact with the external environment, by making at least one section of the casing wall displaceable relative to the coupling formation such that the breathing gas filter can be pushed out of the casing through the access opening by moving the displaceable wall section relative to the coupling formation.

[0042] In principle, the movable wall section can be designed similarly to a movable piston in a cylinder, so that it can be brought into contact with the breathing gas filter, more precisely with its reinforcing edge, and preferably with its frame surrounding the filter material, and can be pushed out of the access opening by moving the wall section. In this case, the breathing gas filter is in the storage state of a breathing gas filter assembly comprising the breathing gas filter and the housing, located between the movable wall section and the access opening. While such a complex movable wall section is theoretically possible, it is not preferred due to the complexity of this design.For reasons of simple manufacturing and handling, and thus also for reasons of keeping costs as low as possible, it is preferred that the casing be designed, at least in sections, to be flexible such that the displacement of the breathing gas filter through the access opening is a deformation of the displaceable wall section. The casing can be made, at least in its deformable wall section, of a soft, elastic plastic, such as a polyolefin or particularly tear-resistant polyethylene terephthalate, especially a dimensionally unstable plastic film. However, the casing can still be deformable with greater wall thicknesses using an elastomer, such as rubber or silicone. The casing can be designed, at least in sections, as a bellows that is deformable towards and away from the access opening.In the case of at least partial formation of the shell as a bellows, the shell can also be made of a stiffer material which, as a flat outer surface with the same thickness as an elastomer shell that is easily deformable by hand, can only be deformed with considerably greater force or by hand without tools.

[0043] Again, the casing for the effective insertion of the breathing gas filter from an interior space of the casing, through the insertion opening, into the filter housing of the filter holder, is preferably designed to be deformable at least at its end furthest from the coupling formation. The casing can be designed to be deformable from this furthest end to its access opening. "Deformable" here refers to deformability without tools, even by hand, by a weak person such as an untrained elderly person.

[0044] When it is stated above that the breathing gas filter assembly, i.e., the casing with the breathing gas filter contained therein, is coupled to the coupling counter-formation in the transfer state by the coupling formation of the casing in the manner described above, this does not mean that the breathing gas filter assembly is only coupled or can only be coupled to the coupling counter-formation in the transfer state, although this is not to be excluded. Preferably, the coupling formation and the coupling counter-formation already allow coupling to be initiated before the transfer state is reached, whereby the casing or the breathing gas filter assembly, once coupling has been initiated, can be displaced relative to the filter carrier along a coupling path into a relative position corresponding to the transfer state. So that the casing orTo ensure that the breathing gas filter assembly can be held in the transfer state with sufficient holding force by the coupling engagement, the coupling path preferably runs transversely to the insertion path of the breathing gas filter when it is inserted into the filter holder. This allows the coupling engagement of the coupling formation and coupling counter-formation along the insertion path to form an anti-lift device, preferably a positive-locking anti-lift device due to its high reliability. Therefore, the coupling engagement of the coupling formation and coupling counter-formation is preferably a positive-locking coupling engagement.

[0045] The coupling element can be formed separately from the rest of the casing and connected to it. This is preferred if the casing skin surrounding the breathing gas filter is formed from a dimensionally unstable plastic film. According to the invention, the coupling element is designed as a rigid component and can be connected to the skin, for example by bonding or welding.

[0046] Then, if the skin of the casing is sufficiently dimensionally stable to absorb expected holding forces during a filter change in the area of ​​the coupling intervention, the coupling formation can be formed integrally with the skin of the casing.

[0047] While it is not impossible that the casing or breathing gas filter assembly, starting from an initial coupling engagement, is partially or completely rotated around a rotational axis into the transfer state, it is preferred if the casing or breathing gas filter assembly can be moved into the transfer state after an initial coupling engagement by an easily and reliably controlled translational displacement movement. For ease of handling, the casing or breathing gas filter assembly is preferably only displaceable into the transfer state by a translational movement.

[0048] To guide the movement of the shell or the breathing gas filter assembly along its coupling path when a coupling engagement is established between the coupling formation and the coupling counter-formation, a formation consisting of the coupling formation and the coupling counter-formation can comprise at least one projection, and the other formation consisting of the coupling formation and the coupling counter-formation can furthermore have at least one groove, wherein the at least one projection engages in the at least one groove along the coupling path at least in the transition state, preferably already during the relative movement. Thus, a groove encompassing a projection circumferentially around the virtual coupling path can, firstly, guide the movement of the shell or the breathing gas filter assembly along the coupling path. For this purpose, the groove extends along the coupling path. Secondly, the groove encompassing the projection can guide the shell or the breathing gas filter assembly along the coupling path.Secure the breathing gas filter assembly against lifting off the filter carrier orthogonally to the coupling path.

[0049] Preferably, the casing has at least two, or more preferably exactly two, projections or grooves as the coupling element, to provide tilt protection for the casing coupled to the coupling element. These projections or grooves are preferably located on each side of the access opening and are more preferably located on each side of the access opening. The formation of grooves in the side surfaces of the casing allows the casing to be designed with at least two parallel side surfaces, each with a flat, flush-fitting surface that is free of any overhang. This enables the casings or the breathing gas filter assemblies to be efficiently stacked in a direction orthogonal to these parallel, flat side surfaces.

[0050] Alternatively, the coupling formation can comprise at least one, preferably two, projections, wherein, particularly preferably, at least one projection is formed on each side of the access opening. The projection, which preferably extends away from the skin of the shell in the direction away from the access opening, can impart increased dimensional stability to the preferably flexible shell in the area of ​​the access opening.

[0051] Regardless of whether the coupling formation is designed as at least one groove and / or at least one projection, the at least one groove and / or at least one projection extends along the coupling path over the entire length of the access opening for the advantageous sealing of the casing against the filter heater or the filter carrier in the transfer state.

[0052] Typically, respiratory gas filters are planar structures, meaning objects whose dimensions in two mutually orthogonal spatial directions are significantly larger than those in a thickness direction orthogonal to each of these two directions. For efficient space utilization, the casing preferably follows the shape of the respiratory gas filter, so that the casing also has significantly larger dimensions in two mutually orthogonal spatial directions than those in a thickness direction orthogonal to each of these two directions.

[0053] To avoid misalignment, preferably both the casing and the breathing gas filter contained therein are mirror-symmetrical with respect to a plane of symmetry orthogonal to the thickness direction, or shape-invariant with respect to a rotation of 180° with respect to an axis of invariance orthogonal to the thickness direction and the access opening surface. Thus, the direction of flow through the breathing gas filter is preferably irrelevant. It can preferably be subjected to flow in either of two possible opposite directions.

[0054] A particular advantage of introducing a respiratory gas filter into the filter housing from within a casing lies in the possibility of sealing the casing, at least during the transfer state, against the filter holder or the filter heater, so that the respiratory gas pressure prevailing in the ventilation line can be largely or even completely maintained during filter replacement. This applies particularly to the end-expiratory overpressure (PEEP), which is important during ventilation. Therefore, according to an advantageous embodiment of the present ventilation line and / or the respiratory gas filter arrangement, at least one coupling element and coupling counter-element have a sealing structure that, at least during the transfer state, seals against the other element.

[0055] However, it should be noted that even without a separate sealing structure between the coupling formation and the coupling counter-formation, existing gaps can provide sufficient sealing and thus maintain respiratory gas pressure in the ventilation line for the duration of the filter change. This is particularly true if such a gap, similar to a labyrinth seal, is angled multiple times in its course from a first chamber to a second chamber to which it must be separated.

[0056] Preferably, the sealing structure is formed or arranged on the coupling counterform, since the coupling counterform can then be formed on a more dimensionally stable object, such as the housing of a filter heater or on the filter carrier, and thus a sealing structure supported by the coupling counterform can be supported by an advantageously stiff and stable substrate. Preferably, the sealing structure is a sealing strip, particularly preferably with a sealing lip projecting away from the substrate supporting the sealing structure. The sealing strip preferably extends along the coupling path. In order to seal the casing with the access opening as effectively as possible against either the filter heater with the through-opening or the filter carrier with the insertion opening in the transfer state, at least one sealing strip runs on both sides of the through-opening on the filter heater or on the filter carrier.the insertion opening, specifically over a length that is at least equal to the length of the access opening along the coupling path, and preferably greater than the length of the access opening along the coupling path. For the sake of the most effective sealing possible, each of the sealing strips is preferably longer than the longer of the two openings opposite each other in the transfer state, namely the access opening and the passage opening, or the access opening and the insertion opening.

[0057] Preferably, the sealing structure is made of a less rigid material than the supporting formation consisting of the coupling formation and the coupling counter-formation. A deformation formation on a groove also qualifies as a sealing structure, provided that the deformation formation is designed such that it presses against a projection inserted into the groove, deforming and thus sealing the projection. This applies particularly if the projection is made of an elastomer, such as rubber or silicone, which is generally suitable for sealing applications. In this case, the sealing structure designed as a deformation formation can be made of the same material or even a stiffer material than the supporting formation. Naturally, this also applies, mutatis mutandis, to a sealing structure designed as a deformation formation on the projection, which serves to deform a section of the groove.

[0058] A deformation formation acting as a sealing structure can be tapered away from the supporting formation to facilitate deformation of the adjacent component section by increasing the surface pressure at its end furthest from the formation. Preferably, the sealing structure, and this also applies to the deformation formation, has a constant cross-section at least partially, and preferably completely, along the coupling path, at least in a region where the sealing structure runs alongside one of the openings opposite each other in the transfer state.

[0059] The advantages mentioned above are described using the example of introducing a new breathing gas filter into the filter housing. However, they also apply to the removal of a used breathing gas filter from the filter housing. Therefore, it is preferably provided that the breathing gas filter can be removed from the filter housing along a removal path, wherein the filter carrier or the filter heater has a further coupling counterform, and a casing can be coupled to this further coupling counterform such that, in a discharge state where the access opening of the casing aligns with the removal opening along the removal path, the casing is held against the further coupling counterform. Preferably, the removal path is the guide track defined by the guide structure mentioned above.

[0060] An empty casing, left over after the breathing gas filter is inserted from the housing into the filter receiving chamber, can thus be stored and, during the next filter change, coupled with the corresponding coupling formation before the used breathing gas filter is pushed out by the new breathing gas filter. The used breathing gas filter can then be pushed into the receiving casing – inaccessible to the personnel performing the filter change.

[0061] The further coupling counterformation is preferably designed like the coupling counterformation described above, so that it can interact with the coupling formation of the shell in the same way as the coupling counterformation. Therefore, further developments of the coupling counterformation described above are also further developments of the further coupling counterformation.

[0062] The insertion of a new respiratory gas filter from a respiratory gas filter assembly in coupling engagement with the coupling counter-formation, and the resulting ejection of a used respiratory gas filter from its operating position into a receiving shell in coupling engagement with the further coupling counter-formation, enables a particularly advantageous, continuous maintenance of the respiratory gas pressure prevailing in the ventilation line. This allows the filter exchange to be carried out with virtually no impact on the ventilation of a patient connected to the ventilation line while mechanical ventilation is ongoing.

[0063] As described above, the breathing gas filter preferably has a gas-impermeable frame surrounding a filter material. This frame can reliably support a centrally accessible filter material housed within the frame and hold it in the breathing gas flow. An advantageously efficient and continuous flow of breathing gas through the filter material, while minimizing leakage from the filter chamber, can be achieved by providing a sealing element, in particular a sealing lip, at a distance from the breathing gas flow path, preferably between the breathing gas flow path and the inlet opening and / or the outlet opening, and more preferably at the edge region of the inlet opening and / or the outlet opening. This sealing element rests tightly against the frame of the breathing gas filter in the operating position.To achieve the most comprehensive and long-lasting sealing effect possible, the sealing formation preferably runs in a closed configuration around the breathing gas flow path, wherein the part of the filter material of the breathing gas filter accessible to the breathing gas flow is preferably located completely radially within the area enclosed by the sealing formation.

[0064] In principle, this sealing element can also be arranged on or / and formed on the frame of the breathing gas filter. However, a frame interface that is as smooth as possible and orthogonal to the flow direction of the filter material is preferred for simplified stacking of even larger quantities of breathing gas filters or breathing gas filter assemblies.

[0065] The present disclosure relates to a breathing gas filter arrangement, as described above, comprising a breathing gas filter housed in a casing, wherein the casing has a coupling element for coupling with a coupling element of a filter carrier or a filter heater, and an access opening for dispensing the breathing gas filter from the casing. At least one wall section of the casing is displaceable relative to the coupling element such that the breathing gas filter can be ejected from the casing through the access opening by displacing the displaceable wall section relative to the coupling element. Further developments and embodiments of the casing and / or the breathing gas filter described above are further developments of the breathing gas filter arrangement.

[0066] To ensure that the breathing gas filter can be stored sterile within the casing until it is dispensed through the access opening, the access opening is, according to the invention, closed by a removable or destructible closure before being coupled to the filter holder or the filter heater. The closure can be formed by a strip of material covering the access opening and removable, particularly peelable, from it. Alternatively, the closure can be formed by a separately designed lid, the surface of which covers the access opening in the storage state and from which a collar projects into an interior space enclosed by the casing in the storage state, where it rests against sections of the casing's inner surface.

[0067] The closure can also be formed by a strip of material that is destroyed, for example, by breaking or tearing, when the breathing gas filter is pushed out of the housing. The closure can also be a burst closure with a predetermined breaking point designed as a material weakening, at which the closure loses its material integrity when a limiting load is exceeded by the breathing gas filter pressing against the closure. The material weakening can be a perforation or a thinning of the material, for example, by embossing or partial cutting through less than the full material thickness, and the like.

[0068] Multiple respiratory gas filter assemblies can be stacked in a dispenser container. The dispenser container can have a dispensing opening through which one respiratory gas filter assembly at a time can be removed from the stack. Preferably, the dispensing opening is located at a geodetically lower end of the dispenser container in its operating state, so that after a respiratory gas filter assembly is removed through the dispensing opening, the remaining stack in the dispenser container falls downwards under the influence of gravity, and another respiratory gas filter assembly is ready for removal in the dispenser container in front of the opening.

[0069] The present disclosure also relates to a ventilation device for at least partial artificial ventilation of a living patient, comprising: a breathing gas source, a ventilation line assembly to convey inspiratory breathing gas from the breathing gas source to a patient-side proximal breathing gas outlet and to convey expiratory breathing gas from a proximal breathing gas inlet, a flow sensor assembly for quantitatively measuring the inspiratory and / or expiratory breathing gas flow in the ventilation line assembly, a pressure changing device for changing the pressure of the breathing gas in the ventilation line assembly, and a control device for operating the breathing gas source and / or the pressure changing device. wherein the ventilation line arrangement includes a ventilation line designed and further developed as described above.

[0070] The breathing gas source can be a blower that draws ambient air from the surrounding atmosphere, a storage container with breathing gas, or a connection assembly for linking to a building installation for breathing gas supply, as is often found in hospitals.

[0071] The pressure changing device can also be the blower, which is also part of the breathing gas source. Additionally or alternatively, the pressure changing device can include at least one valve.

[0072] The present disclosure will be explained in more detail below with reference to the accompanying drawings. It depicts: Fig. 1 a schematic exploded view of a ventilation device, Fig. 2 a rough schematic exploded view of a first embodiment of a ventilation line as a component of the ventilation device of Figure 1Fig. 3 shows a rough schematic perspective view of a change of breathing gas filters (filter exchange) on the ventilation line of Figure 2 , Fig. 4A a rough schematic sectional view of the filter holder of the Figure 2 and 3 with the breathing gas filter arranged in the operating position, Fig. 4 Legs Enlargement view of the circled detail of Figure 4A , Fig. 5 a rough schematic perspective view of a second embodiment of a ventilation line as a component of the ventilation device of Figure 1 , Fig. 6 a rough schematic perspective view of the ventilation line of Figure 5 during a filter change, Fig. 7A a rough schematic perspective longitudinal section view of the ventilation line of the Figure 5 and 6 Before a filter change, Fig. 7 Legs Enlarged view of the marked rectangular area of Figure 7A , Fig. 8A a rough schematic perspective longitudinal section view of the ventilation line of the Figure 5and 6 After a filter change, Fig. 8 Legs Enlargement view of the marked rectangular area of Figure 8A , and Fig. 9 a rough schematic perspective view of a dispenser container for the individual dispensing of respiratory gas filter arrangements of the present application.

[0073] In Figure 1 An embodiment of a ventilation device is generally designated by 10. The ventilation device 10 comprises a breathing gas source 12 in the form of a blower and a control device 14 for adjusting operating parameters of the breathing gas source 12. The breathing gas source 12 and the control device 14 are housed in the same casing 16. This casing also contains valves known per se, such as an inspiratory valve and an expiratory valve. These are arranged in Figure 1 however, not shown separately.

[0074] The control device 14 of the ventilation device 10 has an input / output unit 18, which includes numerous switches, such as pushbuttons and rotary switches, to allow data to be entered into the control device 14 as needed. The blower of the breathing gas source 12 can have its delivery rate varied by the control device 14 in order to change the amount of breathing gas delivered by the breathing gas source per unit of time. Therefore, in the present embodiment, the breathing gas source 12 is also a pressure-changing device 13 of the ventilation device 10.

[0075] A breathing gas source 12 is connected to a breathing line assembly 20, which in this example comprises seven flexible tubes. A first inspiratory breathing tube 22 runs from an optional filter 24 located between the breathing gas source 12 and itself to a conditioning device 26, where the breathing gas supplied by the breathing gas source 12 is humidified to a predetermined humidity level and, if necessary, mixed with aerosol medications. The filter 24 filters and cleans the ambient air supplied by the blower, which serves as the breathing gas source 12.

[0076] A second inspiratory breathing tube 28 leads from the conditioning device 26 to an inspiratory water trap 30. A third inspiratory breathing tube 32 leads from the water trap 30 to a Y-connector 34, which connects the distal inspiratory line 36 and the distal expiratory line 38 to form a combined proximal inspiratory-expiratory breathing line 40.

[0077] From the Y-connector 34 back to the housing 16, a first expiratory breathing tube 42a leads to a breathing gas filter device 64. From this, a second expiratory breathing tube 42b leads to an expiratory trap 44 and from there a third expiratory breathing tube 46 to the housing 16, where the expiratory breathing gas is released into the environment U via an expiratory valve (not shown).

[0078] On the patient-adjacent combined inspiratory-expiratory side of the Y-connector 34, a flow sensor 48, specifically a differential pressure flow sensor 48, is located directly after the Y-connector 34. This sensor detects the inspiratory and expiratory flow of respiratory gas towards and away from the patient. A line assembly 50 transmits the gas pressure on both sides of a flow obstruction in the flow sensor 48 to the control device 14. The control device calculates the amount of inspiratory and expiratory respiratory gas flowing per unit of time from the transmitted gas pressures, and in particular from the difference in gas pressures.

[0079] Moving away from the Y-connector 34 and towards the patient, a measuring cuvette 52 follows the flow sensor 48 for non-dispersive infrared detection of a predetermined gas fraction in the exhaled gas. In the example shown, the CO₂ fraction in the exhaled gas is to be determined. The CO₂ fraction is of particular interest in both the inspiratory and expiratory exhaled gases, as the change in the CO₂ fraction between inspiration and expiration is a measure of the metabolic capacity of the patient's lungs.

[0080] The sensor assembly 54 can be detachably coupled to the measuring cuvette 52 such that the sensor assembly 54 can illuminate the measuring cuvette 52 with infrared light through window 53. From the spectral intensity of the infrared light after illuminating the measuring cuvette 52, the amount or proportion of CO₂ in the breathing gas can be determined in a known manner based on the extent of absorption of infrared light.

[0081] The sensor assembly 54 is connected to the control device 14 of the ventilation device 10 via a data line 56 and transmits intensity information of the detected infrared light to the control device 14 for evaluation via the data line 56.

[0082] Following the measuring cuvette 52, a further tube section 58 extends towards the patient, to which an endotracheal tube 60 is attached as the ventilation interface to the patient. A proximal opening 62 of the endotracheal tube 60 serves both as a breathing gas outlet, through which inspiratory breathing gas is introduced into the patient via the endotracheal tube 60, and as a breathing gas inlet, through which expiratory breathing gas is returned from the patient to the endotracheal tube 60.

[0083] Reference numeral 64 designates a heated respiratory gas filter device arranged in the first expiratory breathing tube 42, which is subsequently described with reference to the Figures 2 to 4 will be described in detail.

[0084] The heated breathing gas filter device 64 forms, as described below with reference to Fig. 2 An embodiment of a ventilation line 65 of the present disclosure will be explained.

[0085] In Figure 2 The breathing gas filter device 64 is shown in a rough schematic exploded view. A filter heater 66 and a filter holder 68, which can be detachably inserted into the filter heater 66, are visible.

[0086] The filter heater 66 includes, on the side facing the viewer, the Figure 2 On the opposite side a filter carrier receptacle 70, into which the filter carrier 68 can be inserted along the arrow 71.

[0087] The housing 67 of the filter heater 66 has a recess 67a on its underside, which serves to receive an inlet-side connecting nozzle 72 of the filter carrier 68 when the filter carrier 68 is in its operating position in the filter carrier receptacle 70 of the filter heater 66.

[0088] The connecting piece 72 forms part of the breathing gas flow path of the ventilation line 65. In the connecting piece 72, breathing gas, in this case expiratory breathing gas, indicated by thick arrows 74 in its flow direction, is introduced into the filter holder 68, more precisely into its Figure 4AThe recognizable filter chamber 76 is introduced into the filter carrier housing 77. The connecting nozzles 72 can serve for the flow-mechanical connection of the first expiratory breathing tube 42a. The breathing gas 74 flows along a virtual breathing gas flow path AS, which is imagined to pass centrally through the exemplary cylindrical connecting nozzle 72 and which, in the example of the cylindrical connecting nozzle 72, coincides with its cylinder axis. Inside the filter carrier 68, the further course of the virtual breathing gas flow path AS, which is concealed by the wall 78 of the filter carrier 68, is indicated by dotted lines.

[0089] At a radial distance from the virtual breathing gas flow path AS, the wall 78 of the filter carrier 68 has an insertion opening 80 through which a breathing gas filter 82 was inserted into the filter carrier 68 along the insertion direction E. The breathing gas filter 82 in Figure 2is in its operating position, in which it cleans the breathing gas 74 flowing through the filter carrier 68.

[0090] In the illustrated example, the wall 78 of the filter carrier 68 has a frustoconical section 78a. However, this section can have any other shape. The frustoconical section 78a offers the advantage of a secure, large-area coupling to the filter heater 66, enabling a sufficiently large amount of heat to be transferred uniformly across the surface of the frustoconical section 78a per unit of time.

[0091] After passing through the filter chamber 76 and the breathing gas filter 82, if present therein, the breathing gas 74 flows out of the filter carrier 68 through the outlet-side connecting nozzle 84.

[0092] The filter carrier 68 can again have a conical section on its outlet side, which tapers from the filter receiving chamber 76, wherein the outlet-side connecting piece 84, which in turn can serve for the flow-mechanical connection of a breathing tube, for example the second expiratory breathing tube 42b, is arranged approximately centrally on the outlet side of the filter carrier 68. Alternatively, the outlet-side connecting piece 84 can be arranged eccentrically on the outlet side of the filter carrier 68 if this is advantageous for the further routing of the tubing.

[0093] As in Figure 2As can be clearly seen, the inlet-side section of the breathing gas flow path AS in the area of ​​the inlet-side connection nozzle 72 and the outlet-side section of the breathing gas flow path AS in the area of ​​the outlet-side connection nozzle 84 are angled towards each other in order to be able to arrange as large an area as possible of the filter carrier 68 in a continuous heat transfer relationship with the filter heater 66, despite the inlet-side connection nozzle 72 projecting from the filter carrier 68.

[0094] The wall 67 of the filter heater 66 advantageously features a through-opening 69 which, when the filter holder 68 is in its operational position within the filter heater 66, aligns with the insertion opening 80 of the filter holder 68 along the insertion direction E. This makes it possible to insert a breathing gas filter 82 into the filter holder 68 through the through-opening 69 and the insertion opening 80 without having to remove the filter holder 68 from the filter heater 66. The filter heater 66 can be removed from the filter holder 68 without having to open the breathing line or interrupt the breathing gas flow.

[0095] The arrangement of the insertion opening 80 such that it is formed in a wall 78 of the filter carrier 68 located radially away from the respiratory gas flow path AS, enables the insertion of a respiratory gas filter 82 into the filter receiving chamber 76 without interrupting the flow path of the respiratory gas 74 and thus the artificial ventilation of the patient.

[0096] In Figure 3This demonstrates a particularly advantageous filter change method, as it is both simple and hygienic. A used breathing gas filter 82b is ejected by inserting a new breathing gas filter 82a through the insertion opening 80 in the insertion direction E from a removal opening 86 located opposite the insertion opening 80 on the wall 78 of the filter carrier 68. Consequently, the used breathing gas filter 82b does not need to be touched to remove it from the filter carrier 68. If, for example, a collection container is located below the removal opening 86, the used breathing gas filter 82b can simply be pushed or ejected into the collection container by the new breathing gas filter 82a. The used breathing gas filter 82b can then be disposed of, again without requiring any contact by the operator.

[0097] The breathing gas filters 82 have a filter frame 88 which, in the example shown, surrounds a flat filter material 90. This allows sufficient force to be exerted by the new breathing gas filter 82a, which is to be inserted into the filter carrier 68, on the used breathing gas filter 82b, which is to be removed from the filter carrier 68.

[0098] The filter frames 88 are made of gas-impermeable material, so that a Figure 2In the operating position of the breathing gas filter 82, a frame section 88a projecting from the insertion opening 80 can seal the insertion opening 80 – and a corresponding frame section can similarly seal the extraction opening 86. Thus, simultaneously with the insertion of a breathing gas filter 82 into its operating position in the filter carrier 68, the filter chamber 76 containing the breathing gas filter 82 is sealed from the external environment U by the breathing gas filter 82, more precisely by its frame 88. At the extraction opening 86, a section of the frame 88 of the breathing gas filter 82, inserted into the operating position, may project out of the extraction opening 86. However, this is not mandatory.

[0099] On the frame sides of the filter frames 88, a locking counter-formation 92 is provided, designed as a toothing, in particular a sawtooth toothing with successive differently inclined tooth surfaces 92 and 92b, which is particularly well integrated into Figure 4BThe recognizable complementary inhibition formation 94 of the filter carrier 68 works together to allow only one movement of a breathing gas filter 82 in the insertion direction E through the insertion opening 80 relative to the filter carrier 68 and to inhibit a movement of the breathing gas filter 82 in the opposite direction.

[0100] A breathing gas filter 82 can thus be inserted into and removed from the filter carrier 68 or the filter receiving chamber 76 along a preferred straight, kink-free guide path FB. The breathing gas filter 82 can therefore be moved through the filter carrier 68 along the straight, kink-free guide path FB.

[0101] As in the Figures 4A and 4BAs can be seen, a complementary inhibiting formation 94 is formed on a wall section 78b of the wall 78 of the filter carrier 68, which laterally delimits the filter receiving chamber 76. This inhibiting formation 94 interacts with the inhibiting formation 92 in such a form-fitting manner that the breathing gas filter 82 can only move unidirectionally along the guide path FB through the filter carrier 68. The inhibiting formation 92 and the inhibiting formation 94 do not need to be strictly complementary to each other. It is sufficient if the desired inhibiting effect is achieved.

[0102] The inlet opening 80 and the outlet opening 86 are end regions of a channel 96, which extends through the filter carrier 68 along the guide track FB and forms the filter receiving chamber 76. The lateral boundaries of the channel 96, defined by the filter carrier 68 or its wall 78, form a guide structure 97. Due to its dimensions, this guide structure allows only unidirectional translational, i.e., rotation-free, movement of the breathing gas filter 82 through the inlet opening 80 into the operating position and out of the operating position through the outlet opening 86. Thus, the breathing gas filter 82 is advantageously free of play in its operating position and is held in the filter carrier 68 with a gas seal at the inlet opening 80 and the outlet opening 86.

[0103] Filter 24 may differ from the representation in Figure 1 may be omitted or may be designed like the respiratory gas filter device 64 or the ventilation line 65.

[0104] The location of the breathing gas filter device 64 in the ventilation line assembly 20 in the exemplary embodiment is merely illustrative. Alternatively, the following representations are shown: Fig. 1 The breathing gas filter device 64 can also be arranged between the water trap 44 and the expiratory valve.

[0105] In the Figures 5 to 8B A second embodiment of a ventilation line 65' with a breathing gas filter device 64' is shown. Identical and functionally equivalent components and component sections in the second embodiment are provided with the same reference numerals as in the first embodiment. Figures 1 to 4B , however, with the addition of an apostrophe. The second embodiment is described below only to the extent that it differs from the previously described first embodiment, to whose description reference is otherwise expressly made for the explanation of the second embodiment.

[0106] The ventilation line 65' of the second embodiment with its breathing gas filter device 64' is shown without filter heating for the sake of clarity. The breathing gas delivery device 64' of the second embodiment can also have filter heating.

[0107] The breathing gas filter 82' is in Figure 5 The device is shown in its stored state, in which it is contained in a casing 98'. The casing 98' and the breathing gas filter 82' contained therein form a breathing gas filter assembly 100'.

[0108] The casing 98', and thus the entire breathing gas filter assembly 100', has a coupling formation 102' on one side, which serves to create a coupling engagement with a coupling counter-formation 104' on the housing 77' of the filter carrier 68'. In the illustrated example, the casing 98' itself is made of an elastomeric material, for example, rubber or silicone, and surrounds the breathing gas filter 82' with a small gap or rests directly against the frame 88' of the breathing gas filter 82'.

[0109] The breathing gas filter 82' is shown without an inhibition formation, but preferably has one.

[0110] The coupling formation 102' surrounds a Figure 5An inconspicuous access opening 106' through which the breathing gas filter 82' can be dispensed from the casing 98'. The access opening 106' is closed by a closure 108' in the form of a film 110' sealed onto the coupling element 102' and can be opened by pushing the breathing gas filter 82' through the film 110', which has a predetermined breaking point. For this purpose, at least one wall section 113' at the longitudinal end 112' of the elastomeric casing 98' opposite the coupling element 102' can be deformed and displaced towards the coupling element 102'.

[0111] The coupling formation 102' comprises, on both sides of the access opening 106', a projection 114' extending over the entire length of the shell 98' and beyond, which projects beyond the main plane of extension of the shell 98'. The two projections 114' can be inserted into a groove 116' of the coupling counter-formation 104' along the coupling path KB', which is orthogonal to the guide path FB'. Grip sections 118' at both longitudinal ends of the coupling formation 102' facilitate handling of the shell 98' or the breathing gas filter assembly 100' during the insertion of the projections 114' into the grooves 116' and during the movement of the shell 98' along the coupling path KB'.

[0112] The two grooves 116' extend on both sides of the insertion opening 80' along the coupling track KB' over the entire length of the insertion opening 80' and beyond on both sides of the insertion opening 80'.

[0113] In contrast to the first embodiment, the frame 88' of the breathing gas filter 82' has, by way of example, a circular opening through which the flat filter material 90' is accessible for the flow of breathing gas. Of course, the opening in the frame 88' can also be rectangular or, more generally, polygonal.

[0114] In Figure 6 A filter exchange of breathing gas filters 82' of the second embodiment is shown. The illustration of Figure 6 This therefore corresponds to the representation of Figure 3 , however, using the second embodiment of the breathing gas filters 82'.

[0115] The breathing gas filter assembly 100' was brought into the transfer state after a coupling engagement was established between the coupling formation 102' and the coupling counter-formation 104', more precisely between the projections 114' and the associated grooves 116', in which the access opening 106' and the insertion opening 80' were aligned with each other along the guide track FB', which in this case represents an insertion movement path.

[0116] In the designated transfer state, pressure on the wall section 113' at the longitudinal end 112' of the casing 98' or the breathing gas filter assembly 100' displaced the longitudinal end 112' towards the access opening 106', deforming the casing 98' and thereby breaking the closure 108'. Through the access opening 106' thus opened, a new breathing gas filter 82a' is inserted along the guide track FB' into the filter receiving chamber of the filter carrier 68', and simultaneously an old or used breathing gas filter 82b' is pushed out of the filter receiving chamber through the removal opening 86' along the same guide track FB'. The guide track FB' is therefore also a removal path. Likewise, the insertion direction E or E' is also the removal direction E or E'.

[0117] As a collection container, as mentioned above, a further casing 98', identical to the previously described casing 98', was attached to the filter carrier 68' before the filter exchange began. For this purpose, the filter carrier 68' has a further coupling counterform 120', which is designed identically to the coupling counterform 104' mentioned above. The further coupling counterform 120' is simply located on the opposite side of the breathing gas flow path AS' than the coupling counterform 104'. Therefore, what was said above regarding the coupling counterform 104' also applies to the further coupling counterform 120'.

[0118] The further shell 98' was brought into coupling engagement with the further coupling counter-formation 120', more precisely with its grooves 122', by means of its coupling formation 102', more precisely with its projections 114'. The further shell 98' is located in Figure 6in a discharge state in which the access opening of the further casing 98' is aligned with the removal opening 86' along the guide track FB'. Thus, the used breathing gas filter 82b' is displaced by the insertion of the new breathing gas filter 82a' into the further casing 98' and, after the filter exchange has been completed, can be removed from the filter carrier 68' and disposed of without contact with a person, surrounded by the further casing 98'.

[0119] The coupling of the two heights 98' with the coupling counter-formations 104' and 120' largely seals the insertion opening 80' and the extraction opening 86' from the external environment U' during filter replacement, thus advantageously preventing any impairment of the breathing gas pressure in the ventilation line 65' during the filter change. This allows PEEP to be maintained even during the filter change.

[0120] A particularly advantageous sealing situation in the vicinity of both the insertion opening 80' and the extraction opening 86' is described below using the Figures 7A to 8B explained.

[0121] In Figure 7A A longitudinal section of a breathing gas filter device 64', ready for filter replacement, is shown. The breathing gas filter assembly 100' is in the handover state, so that the new breathing gas filter 82a' is ready for filter replacement. The sealing foil 110' was, in this case, Figure 7A The coupling of the coupling formation 102' with the coupling counter-formation 104' is removed before the coupling engagement is established. A used breathing gas filter 82b' is arranged in the operating position in the filter receiving chamber 76'. In addition, an empty shell 98' with its coupling formation 102' is in coupling engagement with the further coupling counter-formation 120' and is in the ejection state, so that the empty shell 98' is ready to receive the used breathing gas filter 82b'.

[0122] In Figure 7B is the in Figure 7A The marked rectangular section is shown enlarged to illustrate the sealing situation on the breathing gas filter device 64' before the filter change.

[0123] In Figure 7B It is clearly visible how the projections 114' extending from the access opening 106' on both sides of the casing 98' engage in their respective grooves 116' on the coupling counterform 104' of the filter carrier housing 77'. The engagement extends over the entire length of the groove 116'.

[0124] On the surface of each groove 116' facing away from the insertion direction E', a sealing structure in the form of a sealing strip 124' is arranged, which runs along the coupling path KB' and projects from the surface of the groove 116' into the groove space enclosed by the groove 116'. Each sealing strip 124' therefore rests with its end side furthest from the groove surface supporting it against a surface of the projection 114' inserted into the groove 116' that faces the groove surface. The sealing strip 124' thus seals any gap existing between each projection 114' and the associated groove 116' into which it engages. Therefore, during a filter change through the groove 116', there is no direct flow path between the filter receiving chamber 76', in which a desired breathing gas pressure prevails, and the surroundings U'.

[0125] Contrary to the illustration, the sealing strips can additionally or alternatively be arranged on any other wall of the groove 116' which, in the handover state, is opposite an outer wall section of a projection 114'.

[0126] The sealing strip 124' can, for example, be a silicone strip applied along the coupling track KB' to the relevant groove surface, or it can be any other soft elastic sealing material.

[0127] In addition to the sealing structure in the form of the sealing strips 124', a sealing formation 126' is arranged on each of the two filter carrier housing components 77a' and 77b' of the filter carrier housing 77', which preferably surrounds the breathing gas flow path AS' in a closed manner.

[0128] As long as a breathing gas filter 82' is correctly positioned in the operating position within the filter housing 76', the portion of the filter material 90' accessible to the breathing gas flow through the filter carrier housing 77' is shielded from the external environment U' by the sealing formations 126' located on both sides of the filter material 90' against the frame 88' of the breathing gas filter 82'. The sealing formations 126' are identical on both sides of the breathing gas filter 82', for example, by means of a continuous circumferential elastomer strip.

[0129] Then, when the used breathing gas filter 82b' is displaced by the new breathing gas filter 82a' along the guide track FB' through the extraction opening 86', the frame 88' partially disengages from the sealing elements 126' during a period of the extraction movement of the used breathing gas filter 82b', because the filter material 90', which is intended to be accessible to the breathing gas flow, overlaps with the sealing elements 126'. In this case, the sealing elements 126' can no longer completely seal the breathing gas flow against the outside environment in the area where they are opposite the exposed part of the filter material 90' accessible to the breathing gas flow. This is achieved solely through the sealing strips 124', which, due to their sealing effect against the coupling formation 102', continue to ensure the maintenance of the breathing gas pressure prevailing in the ventilation line 65'.

[0130] The presentation of Figure 8A corresponds to the representation of Figure 7A , however, at a time after the filter was changed. Figure 8B shows in turn the in Figure 8A Enlarged view of the marked rectangular area.

[0131] The new breathing gas filter 82a' was created by deforming and displacing the wall section 113' at the longitudinal end 112' of the Figure 7A and 8A The upper casing 98' is moved towards the access opening 106' without direct contact by the operator into the filter receiving chamber 76'. With the insertion movement of the new breathing gas filter 82a', the used breathing gas filter 82b' is moved into the chamber by the engagement of the two frames 88' of the new breathing gas filter 82a' and the used breathing gas filter 82b'. Figure 7A and 8AThe lower shell 98' is extended. The used breathing gas filter 82b' can be moved along the lower coupling path KB2' relative to the filter carrier 68' without direct contact with the breathing gas filter 82b' and thus detached from the filter carrier 68'.

[0132] The further coupling counter-formation 120' is mirror-symmetric with respect to a plane of mirror symmetry parallel to the two coupling tracks KB' and KB2'. Therefore, the respective grooves 122' of the further coupling counter-formation 120' also have surfaces limiting the area which points in the removal direction and in the insertion direction E', respectively, each with a sealing strip 124' (see Figure 8A ). Due to the aforementioned mirror symmetry, the description of the slots 116' also applies to the slots 122', taking into account the mirror symmetry.

[0133] The hulls 98' can be inserted from both sides of the filter carrier 68' along the respective coupling path KB' and KB2' into the coupling counter-formation 104' and into the further coupling counter-formation 120'.

[0134] Then, if a shell 98' is arranged in each of the two coupling counter-formations 104' and 120', sealing strips 124' completely or at least almost completely seal the filter receiving chamber 76' against the external environment U'.

[0135] In Figure 8A The section of the circumferential sealing formation 126' located closer to the extraction opening 86' is recognizable, which now seals against the frame 88' of the newly introduced breathing gas filter 82a'.

[0136] With the breathing gas filter device 64' of the second embodiment, as described in the Figures 5 to 8BAs shown, a replacement of breathing gas filters 82' can be carried out during ongoing ventilation without affecting the breathing gas pressure prevailing in the ventilation line 65'.

[0137] In Figure 9 An advantageous dispenser container 130' is shown, which has a plurality of breathing gas filter arrangements stacked in 100' along the direction of gravity g.

[0138] Through a dispenser opening 132' at the geodetic, i.e. in the direction of gravity g, lower end, the lowest breathing gas filter assembly 100' can be pulled out of the dispenser container 130', whereby the remaining breathing gas filter assembly still in the dispenser container 130' moves forward by gravity, so that after the removal of a breathing gas filter assembly 100', the breathing gas filter assembly 100' that was previously directly above it is now in front of the dispenser opening 132' and is ready for removal from the dispenser container 130'.

[0139] The width of the dispenser opening is 132' in Figure 9 The width along the direction of gravity g is slightly larger than the width of the coupling formation 102' measured in the same direction, so that the breathing gas filter assembly in 100' can only be removed individually from the dispenser container 130' through the dispenser opening 132'. When the lowest breathing gas filter assembly 100', which is ready for removal from the front dispenser opening 132', is wiped off the breathing gas filter assembly 100' located directly above it on the wall section of the dispenser container 100' above the dispenser opening 132'.

Claims

1. Breathing gas filter arrangement (100') including a flexible sleeve (98') and a breathing gas filter (82') accommodated in the sleeve (98'), wherein the sleeve (98') has a coupling formation (102') for coupling to a coupling counter-formation (104') of a filter carrier (68') or of a filter heater (66) as well as an access opening (106') for the delivery of the breathing gas filter (82; 82') from the sleeve (98'), wherein at least one wall section (113') of the sleeve (98') can be displaced relative to the coupling formation (102') in such a manner that the breathing gas filter (82'), as a result of displacement of the displaceable wall section (113') relative to the coupling formation (102'), can be shifted through the access opening (106') out of the sleeve (98'), wherein the displacement of the displaceable wall section (113') is a deformation of the displaceable wall section (113'), characterized in that the coupling formation (102') is an inherently stiff component connected with the sleeve (98'), wherein the access opening (106') in the storage state before coupling to the filter carrier (68') or to the filter heater (66) is closed by a removable or destructible closure (108').

2. Breathing gas filter arrangement (100') according to claim 1, characterized in that the coupling formation (102') surrounds the access opening (106').

3. Breathing gas filter arrangement (100') according to claim 1 or 2, characterized in that both the sleeve (98') and also the breathing gas filter (82; 82') accommodated therein are mirror symmetrical with respect to a mirror symmetry plane orthogonal to the thickness direction or shape invariant under a rotation by 180° with respect to an invariance axis orthogonal to the thickness direction or to the access opening (106') surface.

4. Breathing gas filter arrangement (100') according to claim 1 or 2, characterized in that the coupling formation (102') comprises a sealing structure which is configured for sealingly laying against a coupling counter-formation of the filter carrier or of the filter heater.

5. Breathing gas filter arrangement (100') according to claim 4, characterized in that the sealing structure is produced from a less stiff material than the coupling formation (102') supporting it.

6. Breathing gas filter arrangement (100') according to any one of the preceding claims, <b>characterized in that the breathing gas filter (82; 82') comprises a gas impermeable frame (88; 88') surrounding a filter material (90; 90').

7. Breathing gas filter arrangement (100') according to any one of the preceding claims, including claim 2, characterized in that the closure is formed by a material strip covering the access opening (106'), which is removable from the access opening (106').

8. Breathing gas filter arrangement (100') according to claim 7, characterized in that the material strip is destructible by shifting of the breathing gas filter out of the sleeve.

9. Breathing gas filter arrangement (100') according to any one of the preceding claims, including claim 2, characterized in that the closure as rupturing closure comprises a predetermined breaking point designed as material weakening, where the closure loses its material cohesion when a limit load exerted by the breathing gas filter (82; 82') pressed against the closure is exceeded.

10. Breathing gas filter arrangement (100') according to claim 9, characterized in that the material weakening is a perforation or a thin spot in the material.

11. Breathing gas filter arrangement (100') according to any one of the preceding claims, including claim 2, characterized in that the closure is formed by a separately designed cover, the cover surface of which covers the access opening (106') in the storage state.

12. Breathing gas filter arrangement (100') according to claim 11, characterized in that collar projects from the cover surface of the cover, which, in the storage state, protrudes into an interior space surrounded by the sleeve (98') and there lies against inner surface sections of the sleeve (98').

13. Breathing gas filter arrangement (100') according to any one of the preceding claims, characterized in that breathing gas filter has an inhibiting counter-formation which is configured to cooperate in positive-locking manner with an inhibiting formation of a filter carrier to achieve a unidirectional movability of the breathing gas filter.

14. Breathing gas filter arrangement (100') according to claim 13, characterized in that the inhibiting counter-formation comprises a sawtooth formation formed by a sufficiently elastic material running along a guide path.