PRESSURE MEASURING CAPSULE HOLDER FOR AN EXTRACORPORAL BLOOD TREATMENT MACHINE

Description

[0001] The present invention relates to a pressure measuring capsule holder which is attached or attachable to a housing of an extracorporeal blood treatment machine, in particular a dialysis machine, with a gripping device adapted to hold a pressure measuring capsule inserted into the pressure measuring capsule holder by gripping or engaging it. State of the art

[0002] Extracorporeal blood treatment machines, particularly dialysis machines, have a piping system, specifically a dialysis fluid circuit and an extracorporeal blood circuit. These circuits have a number of dialysis fluid and blood (tube) lines that run through and / or connect various functional units of the extracorporeal blood treatment machine, such as a dialyzer, blood pumps, etc. To ensure the smooth operation of the extracorporeal blood treatment machine, this piping system, especially the blood tubing, must be pressure-monitored at several points. For example, a typical dialysis machine has a PA port to monitor arterial negative pressure, a PBE port to monitor the inlet pressure before the dialyzer, and a PV port to monitor venous pressure.

[0003] For pressure monitoring purposes, pressure sensor capsules or so-called PODs (Oscillating Pressure Membranes) are frequently installed at suitable points in the lines or blood tubing, as is the case, for example, with the commercially available Medisystems Streamline system. These PODs or pressure sensor capsules consist of a rigid capsule divided into two chambers by a membrane: a blood chamber connected to the blood tubing system and a fluid chamber, specifically a gas or air chamber. This fluid chamber is connected via a thin tube or pressure transmission line to a pressure sensor or a corresponding port on the extracorporeal blood treatment machine. Such ports are typically equipped with Luer connectors, which require a screw mechanism to connect the pressure transmission line.Because the pressure sensor capsules are suspended within the tubing of the piping system and thus float in undefined, unstable positions, measurement inaccuracies can occur. During operation, the internal pressure of the piping system, and therefore of the first chamber, is transferred via the diaphragm to the second chamber, creating a fluid pressure, particularly gas pressure, that is dependent on the internal pressure of the piping. The pressure sensor, connected to the second chamber via the thin tubing, receives this fluid pressure signal, which it converts into an electrical signal. The thin, flexible tubing, which creates a large fluid or air gap and a dead volume between the pressure sensor capsule and the pressure sensor, acts as a low-pass filter, thus adversely limiting the measurement accuracy and the pressure sensor's response time.

[0004] Alternatively, DE 10 2006 016 846 B4 discloses the direct connection (without an intermediate hose) of pressure measuring capsules with an air side to a pressure sensor. Furthermore, WO 2014 / 099767 A1 and US 8 210 049 B2 disclose detachable mountings for a pressure measuring capsule, which are attached to a housing or a permanent frame. This means that pressure sensor capsules or PODs are known which are connected directly or via a rigid, short connection to the pressure sensor. A disadvantage of this is that the connections mentioned as examples, such as a Luer-lock connection or a bayonet connection, are complex to assemble and / or disassemble, and / or the requirements for the tightness of the connection may not be met.For example, a Luer-lock connector must be screwed in, making it complex to assemble. Furthermore, overtightening the screw connection can force the individual Luer components too tightly together, making them difficult to disassemble or even damaging them. In summary, modern systems with a Luer-lock connection can be open / disconnected, tight / closed, or loose / leaking (not connected correctly).

[0005] WO 2005 / 068 963 A1 discloses a pressure-measuring capsule for a liquid that can be connected to a liquid-carrying hose. The pressure-measuring capsule contains an air column that is in contact with a diaphragm in the hose. The hose and the pressure-measuring capsule are detachably connected by snap or spring hooks that engage in a groove on the pressure-measuring capsule. If the snap or spring hooks do not fully engage in the groove, a situation can arise in which the pressure-measuring capsule is not completely connected to the hose and is therefore not completely leak-proof.

[0006] EP 1 843 140 A2 discloses a two-part pressure measuring capsule. A pressure sensor is detachably connected to a fluid guide system by a screw connection. The fluid guide system holds the blood, and the pressure sensor holds a fluid. The blood and the fluid are separated by a membrane. This separation of blood and fluid facilitates the replacement of the fluid guide system.

[0007] With known solutions, a situation can be created where the user believes the two parts are connected. However, the connection is insufficient. As a result, the pressure measurement may be inaccurate, or fluid may leak from the connection without the user noticing. Summary of the invention

[0008] The object of the present invention is to improve or eliminate disadvantages of the prior art. In particular, a pressure measuring capsule holder is to be provided that makes it possible to easily mount and dismount pressure measuring capsules and, in particular, still provides a very tight connection to a fluid chamber, especially an air chamber, of a pressure measuring capsule.

[0009] The problem underlying the invention is solved by a pressure measuring arrangement with the features of claim 1.

[0010] More precisely, the task is solved by a pressure capsule holder that can be attached to the housing of an extracorporeal blood treatment machine, in particular a dialysis machine. A gripping device, adapted to hold a pressure capsule inserted into the pressure capsule holder and having at least one blood chamber connection, and an ejection mechanism, adapted to eject the pressure capsule when the gripping device is released, are provided. The interior of the pressure capsule is divided into a blood chamber and a fluid chamber, in particular by a membrane. The pressure capsule holder has a pressure transmission line configured to be fluidically connected to the fluid chamber of the pressure capsule and to transmit the fluid pressure present in the fluid chamber to a pressure sensor of the extracorporeal blood treatment machine.The ejection mechanism comprises a spring mechanism with a pressure element or a clamping component, which is spring-mounted such that it is pre-tensioned when the pressure measuring capsule is inserted and presses against it in a holding position, in which the pressure measuring capsule is held by the gripping device. A preferably conical mounting connection element (hereinafter referred to as "connection element"), preferably made of a soft plastic, and more preferably a Luer connector, is arranged or formed at one outer end of the pressure element. The mounting connection element includes the pressure transmission line.

[0011] The pressure transmission line is, for example, a pressure transmission channel that can be connected to the fluid chamber at its end facing the pressure measuring capsule (if used), particularly when the capsule is inserted into the holder (automatically, without an additional assembly step). Furthermore, the pressure transmission channel can have a connection (at one end opposite the pressure measuring capsule) that can be connected to another pressure transmission line or directly to a pressure transducer (pressure sensor).

[0012] In other words, a gripping device or holding device is provided that holds a pressure-measuring capsule (hereinafter: capsule) and has a mechanism which, when a user simply removes the capsule from the pressure-measuring capsule holder (hereinafter: holder), automatically ejects the capsule. That is, a simple action by the user automatically moves the capsule out of the holder in such a way that another simple action is required to re-engage the capsule with the gripping device. If necessary, the ejection mechanism also at least partially releases a gas-tight connection between the capsule and a pressure transmission line / channel of the extracorporeal blood treatment machine.

[0013] The ejection mechanism is at least partially formed by a spring mechanism. In this case, the capsule can be held against a restoring force of the spring mechanism, which, if necessary, also pushes the capsule out of the pressure capsule holder in the event of frictional forces or similar, as soon as the gripping device is released. In particular, a spring travel must be provided that is sufficiently long so that a user can easily grasp the pressure capsule or, preferably, so that the pressure capsule is completely ejected from the pressure capsule holder and hangs only by the attached lines.

[0014] The pressure measuring capsule holder according to the invention, in particular the interaction between the gripping device and the ejection mechanism, especially the spring mechanism, achieves two things: firstly, very precise and stable positioning of the capsule without the need for additional adjustment of the holder, enabling quick and easy assembly of the pressure measuring capsule; and secondly, it ensures that the pressure measuring capsule can be quickly and easily mounted and dismounted. Furthermore, because the capsule is held securely in the holder and can be ejected in a controlled manner by the ejection mechanism, a situation in which a loose / leaking connection exists between the pressure transmission line and the fluid chamber (e.g., due to an incorrectly connected Luer-lock connection) is avoided. That is, due to the controlled ejection, there are only the states "connected" and "not connected".Furthermore, the pressure sensor capsule clicking into place when inserted into the holder provides haptic, visual, and / or audible feedback indicating correct connection. Various embodiments of the invention in which such clicking can be achieved are described in more detail below.

[0015] In other words, a pressure capsule holder, which is attached to or part of the housing of an extracorporeal blood treatment machine, has a device for positively retaining a pressure capsule and one or more elements, such as springs or guide cams, that generate a force acting against the insertion direction. These elements are provided / mounted in the pressure capsule holder in such a way as to exert a compressive force (spring force) on a pressure capsule held or inserted therein, at least during the removal of the capsule from the holder. This force acts against the insertion direction (i.e., from the inside out) in which the pressure capsule can be inserted into the holder. This assists in removing the capsule from the holder or causes it to be ejected. Preferably, the pressure capsule is inserted from the front or...It is inserted into the pressure sensor capsule holder on the front panel of the extracorporeal treatment machine housing, clearly visible and easily accessible. However, it can also be inserted from the side, from above, or from below (i.e., parallel to the housing).

[0016] By mounting or integrating the pressure capsule holder directly on the outside of the extracorporeal blood treatment machine housing, it can be ensured that the fluid or air chamber of the pressure capsule is connected via a short, rigid pressure transmission line to a pressure sensor. This sensor is preferably located inside the housing of the extracorporeal blood treatment machine, directly behind the pressure capsule holder, and converts a pressure signal from the pressure capsule into an electrical measurement signal. Accordingly, the arrangement of the pressure capsule within the pressure capsule holder enables highly accurate and reliable pressure measurement during operation of the extracorporeal blood treatment machine.

[0017] The ejection mechanism, in particular the spring mechanism, can provide a compressive force for ejecting the pressure capsule by mounting at least one compression spring in the holder such that it sits behind the pressure capsule in the insertion direction. Alternatively, an arrangement with a tension spring is also conceivable. For the spring mechanism, mechanical springs such as coil springs, leaf springs, or disc springs (i.e., an elastically deformable component that provides an elastic restoring force when deformed) or pneumatic springs can be used, individually or in combination (connected in parallel and / or series). Possible designs of the gripping device will be described in more detail later.

[0018] Advantageous embodiments are the subject of the dependent claims and are explained in more detail below.

[0019] InIn other words, the spring mechanism is designed to press against the pressure capsule from the rear (in relation to the insertion direction in which the pressure capsule is inserted into the holder), i.e., essentially between the housing and the pressure capsule. Furthermore, springs do not press directly against the pressure capsule; instead, an intermediate element in the form of the pressure element is provided, allowing the ejection force generated by the spring mechanism to be transmitted evenly and gently to the pressure capsule. For this purpose, the pressure element can, for example, be ring-shaped and rest against an outer edge of the pressure capsule and / or form a recess to receive a part of the pressure capsule. The pressure element preferably has a metal (particularly pressure-resistant) rod.

[0020] Preferably, the gripping device is mounted to the housing via a shaft, with the pressure element being received and spring-mounted within the shaft. The shaft's diameter can essentially correspond to the dimensions of the gripping mechanism, resulting in a particularly robust connection that offers ample space for (partially) accommodating the spring mechanism or pressure element and avoids unnecessary intersections and edges. Alternatively, the shaft can be significantly narrower than the pressure capsule holder, which is more cost-effective and lighter. Furthermore, the shaft allows for the adjustment of a specific distance between the housing and the gripping device to facilitate the insertion of the blood lines. This arrangement also provides sufficient space for the fully protected housing and suspension / bearing of the pressure element.

[0021] The connection element is designed to be complementary to a fluid / air chamber connection element of a fluid or air chamber of the pressure measuring capsule. For example, if the pressure measuring capsule has a female Luer connector, preferably a Luer slip connector, the connection element is designed as a male Luer (slip) connector, or vice versa. Alternatively, for example, an end-face sealing surface can be provided which can be pressed against a complementary surface of the pressure measuring capsule by the spring mechanism. In this case, the ejection mechanism serves in particular to apply force or to press a connection between the capsule and the holder.

[0022] A conical shape of the connecting element enables a particularly robust connection between the pressure capsule and the pressure capsule holder, which is insensitive to slight deviations and guided during insertion. Furthermore, an additional, easily manually releasable connection can exist between the fluid / air chamber connection element of the pressure capsule and the connection element of the pressure capsule holder, which holds the pressure capsule even when the gripping device is released. In particular, a force-fit or friction-fit connection can be provided, for example, by the conical shape of the connecting elements acting as a wedge. In this way, when the gripping device is released, the pressure element, together with the pressure capsule, is moved out of its holding position by the ejection mechanism, preventing the gripping device and pressure capsule from re-engaging in a holding connection.Due to the additional, easily detachable manual connection, especially the wedge connection, the capsule and the associated blood vessels cannot simply fall off when the gripping device is released, but must be additionally loosened or pulled off by a user for disassembly.

[0023] It has proven advantageous to have a seal, preferably an O-ring, attached to the preferably conical connecting element of the pressure element, or for the connecting element itself to function as a seal. In particular, the seal can be located on a contact surface where the connecting elements make contact with each other. This ensures the necessary tightness between the connections of the pressure sensor capsule and the pressure sensor capsule holder for particularly accurate pressure measurement. Furthermore, the seal can serve as an additional, easily detachable connection, thus fulfilling a dual function.

[0024] Alternatively, the seal can be attached to an inner surface of the shaft at the inlet end of the pressure element in such a way that it rests radially against the fluid / air chamber connection element of the pressure measuring capsule, more precisely against a provided, possibly appropriately machined, sealing contact surface when the capsule is inserted into the holder. On the other hand, the seal can be positioned radially on the outside of the pressure measuring capsule, and an inner surface of the shaft can be designed accordingly as the sealing contact surface. The latter is advantageous with regard to simpler manufacturing of the seal seat and the replaceability of the O-ring, i.e., more maintenance-friendly. In these cases, when the gripping device is released, the ejection mechanism displaces the seal axially relative to the opposite sealing contact surface.To protect the seal, it is advantageous if the sealing contact surface and / or the surface to which the seal is attached are at least slightly chamfered. Conversely, it is advantageous if these surfaces are straight cylindrical, as this ensures the same sealing effect even with deviations in the axial position of the pressure capsule and the holder. Furthermore, in such a pressure capsule holder, a pressure rod can be omitted, and an alternative ejection or spring mechanism can be provided, such as on a contact section for an outer surface of the capsule.

[0025] Preferably, the pressure element includes a pressure transmission line that can be connected to the pressure-measuring capsule to transmit the pressure from the capsule to a pressure sensor of the extracorporeal blood treatment machine. In particular, it is advantageous if the spring mechanism has a spring force setting to press the pressure element against the pressure-measuring capsule in the holding position, thus ensuring a gas-tight connection between the capsule and the pressure transmission line.This allows the seal of the pressure element's connection element, as described above, which is pressed against the pressure capsule by the ejection mechanism, particularly a spring mechanism, or can be pressed against it, to provide a tight, secure connection between the fluid or air chamber of the pressure capsule and the pressure transmission line. This line connects the capsule to a pressure sensor, preferably located in the housing of the extracorporeal blood treatment machine. Alternatively, the pressure sensor can also be provided directly connected to the pressure element within the shaft. In particular, the spring-loaded mounting compensates for deviations in the insertion direction (i.e., in the direction of action of the spring mechanism) when the pressure capsule is attached. Alternatively, a pressure transmission line can also be provided within the shaft, which can be connected to the pressure capsule accordingly.In this case, the pressure element is located inside or on the pressure transmission line and is not sealed to the capsule.

[0026] According to a further aspect of the invention, at least one wall section is provided, defining a receiving space for the pressure-measuring capsule. A surface extending substantially perpendicular to the wall section can serve as the base of the receiving space, in which the spring mechanism, and in particular the shaft, is preferably accommodated. The wall section can project from the base of the receiving space at least in such a way that the pressure-measuring capsule is preferably completely enclosed within it. Furthermore, preferably at least two opposing wall sections are provided, defining the receiving space between them. The capsule is protected in the holder by the wall section and is less susceptible to damage from impacts, careless movements, or the like. Preferably, the pressure-measuring capsule is mounted from a front side, i.e.,The pressure capsule is inserted into the pressure sensor holder facing the floor and parallel to the wall sections. However, it is also possible to insert the capsule into the holder from the side or from above, particularly between two or more wall sections. In this case, a guide for the capsule may be provided along the wall sections.

[0027] Advantageously, at least one wall section is provided with a slot for receiving at least one blood chamber connection of the pressure-measuring capsule. The slot thus serves to fix the capsule in position with respect to its blood chamber connections, and is essentially U-shaped and / or adapted to the diameter of the blood chamber connection in such a way that it guides the connection during insertion of the pressure-measuring capsule and, once inserted, holds it securely in three directions (i.e., towards one end of the slot and transversely on both sides). In other words, the slot can serve to receive and guide the capsule section. This virtually eliminates the risk of incorrect insertion. Furthermore, the slot ensures that the pressure-measuring capsule remains securely in position in all three directions even during treatment.If the slot runs primarily in the direction in which the capsule is inserted into the holder, this is also referred to as an axial slot. For example, if the (axial) slot runs perpendicular to the bottom of the receiving chamber, particularly towards the housing of the extracorporeal blood treatment machine, or parallel to the shaft, it can prevent the pressure-measuring capsule from twisting during extracorporeal blood treatment.

[0028] Furthermore, it is preferred if an inner circumferential surface of at least one wall section is formed to serve as a guide for the pressure measuring capsule. For example, the capsule can be substantially round in the insertion direction, and the inner circumferential surface can have a corresponding diameter or curvature. This, as well as providing the slot, can prevent the capsule from tilting and any resulting incorrect connection.

[0029] In an advantageous embodiment, the gripping device forms at least one snap hook designed to engage behind the pressure capsule when it is inserted. That is, at least one hook is provided which extends along the pressure capsule holder in the insertion direction of the pressure capsule, in particular parallel to the aforementioned at least one wall section, and has a lug at its free end projecting towards the interior of the pressure capsule holder (i.e., into the receiving space). The snap hook(s) can be bent outwards like a spring, in particular by the capsule contacting the lug when inserted into the holder and pushing it outwards. This makes inserting the pressure capsule into the holder by a user particularly easy and quick.The snap hook(s) can also form an (additional) wall section, which forms the receiving space in addition to or as an alternative to the wall section(s) described above.

[0030] For example, a single snap hook can be provided, which is advantageous because the connection can be released with one hand. That is, to release the gripping device from the pressure-measuring capsule, a user only needs to bend the single snap hook outwards with one hand, whereupon the ejection mechanism, in particular the spring mechanism, pushes the capsule out of the gripping device in such a way that re-engagement upon releasing the snap hook is impossible. In this case, a first wall section can be provided, defining the receiving space and preferably surrounding it at least halfway, and more preferably over more than two-thirds of its area. This wall section includes, in particular, the two slots running perpendicular to the bottom of the receiving space for receiving the blood chamber connections. The snap hook can, in this case, be arranged in a gap in the first wall section to form a second wall section.Alternatively, two opposing snap hooks can be provided, which can be released with both hands. Between the snap hooks, and preferably at an angle (90°) to them, two wall sections, particularly with slots, can be formed.

[0031] The pressure sensor holder according to this embodiment can, for example, be injection molded, wherein the at least one wall section, the at least one snap hook, a base of the receiving chamber, and optionally the shaft are manufactured in one piece. This enables a particularly cost-effective production of the pressure sensor holder.

[0032] In other words, the holder is equipped with one or two (plastic) hooks designed to lock and hold the pressure sensor capsule (POD) in position. Furthermore, the (plastic) hooks are designed to allow the pressure sensor capsule to be easily released using one or two fingers, one for each hook.

[0033] According to another advantageous embodiment, the at least one slot is a circumferential slot extending transversely to the insertion direction, in particular in the circumferential direction around the receiving space, through which the gripping device is separated or formed on the outside (opposite a bottom of the receiving space) as at least one preferably elastically bendable, circumferentially extending clamp, wherein the at least one blood chamber connection can be inserted into the circumferential slot by rotating the pressure measuring capsule or can be slid under the clamp.

[0034] This means that the pressure sensor holder according to this embodiment has a preferably circumferential wall which, together with the base, defines the receiving space. The wall has at least one slot which runs parallel to the base in the circumferential direction. The at least one slot opens towards an edge of the wall. To enable this, the at least one slot is bent at its entrance in the axial direction (i.e., perpendicular or inclined away from the base) and / or the wall has a projection in each area where the slot(s) run, in which the respective slot opens laterally / circumferentially. Similar to the embodiment described above, the pressure sensor holder according to this embodiment can be manufactured particularly simply and cost-effectively, especially in one piece, preferably by injection molding.

[0035] In other words, the holder has two curved plastic hooks (clips) designed to hold the pressure sensor capsule in position by hooking the tubing / blood chamber connections onto them. With this embodiment of the holder, the connection of the pressure sensor capsule (POD) is achieved by a partial rotation of the component (capsule). Similarly, the pressure sensor capsule is released / removed by a partial rotation of the capsule in the opposite direction.

[0036] To insert the pressure-measuring capsule into the pressure-measuring capsule holder, the capsule is positioned in this embodiment so that its blood chamber connection(s) lies(s) in the entrance of the circumferential slot. The pressure-measuring capsule is then (partially) rotated so that the blood chamber connection moves through the circumferential slot and stops / attaches itself in an end position at its end. This means that inserting and removing the capsule from the holder is bayonet-like and is particularly quick, easy, and can be done with one hand by the user.

[0037] In particular, it is advantageous if at least one circumferential slot is widened at its (bag) end to provide a snap-in receptacle that defines the final position of the respective blood chamber connection. Preferably, the dimensions (diameter) of the receptacle correspond to the dimensions of the blood chamber connection. In this case, clips / wings formed by the circumferential wall, which remain on the outside (facing against the insertion direction or opposite the bottom of the receiving space) of the circumferential slot or are partially separated from the circumferential wall by the circumferential slot, are elastically bendable so that the capsule with its blood chamber connections snaps into a final position at the end of the slot.For this purpose, it is particularly advantageous if a recess is provided on an outer / frontal edge of the wall next to the end of the circumferential end or the connection receptacle, i.e., behind a projection of the clamp / wing. Such a recess increases the flexibility or elastic expandability of the wings / clamps provided on the outside of the circumferential slot, thereby requiring, for example, less force from the user to lock and release the pressure measuring capsule.

[0038] The ejection mechanism can be a spring mechanism, with the circumferential slot preferably extending circumferentially at least at its inner end opposite the inlet (or possibly exclusively). Alternatively or additionally, the circumferential slot can be slightly inclined (i.e., extending around the receiving chamber and obliquely towards the base), so that the circumferential slot forms a guide track as the ejection mechanism. Due to its inclined shape, the capsule is moved out of the holder perpendicular to the base when removed. Furthermore, the guide track thus formed can generate a contact force towards the base and a connection point or seal provided thereon when the capsule is inserted.

[0039] According to yet another preferred embodiment, the gripping device comprises a sleeve-shaped rotary latch or locking ring rotatably mounted on an outer surface of at least one wall section, which has at least one L-shaped slot. The L-shaped slot has an axial section that opens in the opposite direction of insertion at an outer (end-face) edge of the rotary latch. In an open position of the rotary latch, the axial section overlaps the at least one axially extending slot (axial slot) provided in the wall section such that the at least one blood chamber connection can be inserted into the respective L-shaped slot and axial slot.Furthermore, the L-shaped slot has a circumferential section that forms a circumferentially extending slot end and is adapted to hold the at least one blood chamber connection in a closed position, achievable by rotating the rotary latch, together with the axial slot. The pressure capsule holder or gripping device according to this embodiment holds the pressure capsule particularly stably and securely. It is also advantageous that the rotary latch serves as a circumferential protective barrier to safeguard the pressure capsule. Optionally, the rotary latch can be spring-loaded to be pre-tensioned in the closed position.

[0040] Similar to the embodiment described above with the circumferential slot, the ejection mechanism can be formed by the spring mechanism and / or by a guide track, the guide track in this case being provided by the circumferential section of the L-shaped slot. If only the spring mechanism is provided, the circumferential section preferably extends exclusively in the circumferential direction. The guide track is formed by the circumferential section of the L-shaped slot having an axial component in addition to its circumferential component (running around the receiving space and obliquely towards the bottom).When the rotary latch is turned / closed, an outer edge of the L-shaped slot presses against the respective blood chamber connection, pushing the capsule into the receiving chamber / towards the bottom and, if necessary, pressing any seals between the fluid / air chamber connection element of the capsule and the connection element of the holder (e.g., the shaft or the pressure element) together. If a spring-loaded pressure element is present, i.e., if the ejection mechanism has both a spring mechanism and a guide cam, the spring mechanism for ejecting the capsule is assisted by a lower edge of the L-shaped slot when the capsule is released. This is particularly advantageous due to the high contact force that can be achieved and the potential for jamming, as the guide cam reduces the force required for ejection and also ensures a more controlled ejection.This means that when the capsule is removed, an automatic ejection of the capsule is provided.

[0041] In other words, the pressure capsule holder is equipped with a rotating outer ring designed to rotate during insertion of the pressure capsule or to be rotated manually. Furthermore, the rotating outer ring can be designed to push the capsule out of the holder during rotation.

[0042] According to yet another advantageous embodiment, the gripping device forms a locking tab attached via a hinge-like joint or slidably mounted in such a way that, in a closed position, it extends over the pressure measuring capsule on a side opposite the spring mechanism in order to hold it in the holder against a spring force of the spring mechanism.

[0043] Preferably, the locking tab forms a detent edge or detent hook / detent projection at an end opposite the hinge, in order to engage with a corresponding hook, edge, or groove rigidly provided on the holder in the closed position. Preferably, the hook or projection is a snap hook or detent lug, and engagement is achieved by snapping it into place. Alternatively, a manually movable hook, lever, or pin (rotatably or slidably mounted) can be provided to create an undercut retaining engagement between the locking tab and a main body of the pressure-measuring capsule holder. Furthermore, it is advantageous if the locking tab has a truss-like design so that the pressure-measuring capsule, in particular a main body containing the air and blood chamber, is visible even when the locking tab is closed.

[0044] In particular, if the locking tab is attached via the hinge-like joint, the locking tab can also be designed as a bending spring that can exert an additional clamping force on the pressure-measuring capsule inserted into the holder. Alternatively, it is conceivable to design the locking tab as a bending spring rigidly attached to the pressure-measuring capsule holder, which is bent open to insert the pressure-measuring capsule and which then holds the capsule in the holder (exclusively) by its spring force.

[0045] In other words, the holder is equipped with a plastic lid designed to keep the capsule in the correct position, with a hook holding the lid in the closed position. The lid secures the capsule. Specifically, the holder is equipped with a Luer-lock connector.

[0046] In each of the embodiments described above, it is advantageous if the pressure capsule holder is designed such that the main part / body of the pressure capsule with the blood and fluid / air chambers separated by the membrane is visible, so that a user can easily monitor the positioning / adjustment of the membrane that separates the two chambers.

[0047] In summary, the problem underlying the invention is solved by a direct connection of the capsule (POD) to the extracorporeal blood treatment machine or dialysis machine (its housing), in which the pressure-measuring capsule is held in the correct position during extracorporeal blood treatment (dialysis treatment). The holder is designed to hold / attach the capsule to a front panel of the extracorporeal blood treatment machine. Furthermore, the holder allows inspection of the capsule membrane's position (the membrane separating the capsule's chambers). The holder keeps the capsule in the correct position and prevents rotation. The holder allows pressure to be transmitted between the blood lines and the extracorporeal blood treatment machine. The pressure-measuring capsule is prevented from kinking relative to the tubing (e.g.,The need for a pressure transmission (hose) line between the capsule's fluid / air chamber and the pressure sensor is avoided. The holder allows for the connection of plastic hoses. Furthermore, the holder is designed for easy cleaning and removal from the machine for maintenance purposes. The holder can also be equipped with a soft plastic connector (connecting element and / or seal) to connect the capsule, ensuring a seal with the capsule. The soft plastic connector is mounted on a metal shaft (pressure element). Finally, the holder is designed to automatically eject the capsule when it is removed. Character description

[0048] The present invention is described below with reference to preferred embodiments. These are, however, only illustrative and are not intended to limit the scope of protection of the present invention. Furthermore, the same reference numerals are used for identical components when describing the different embodiments in order to avoid redundant descriptions. Fig. 1 shows a pressure measuring capsule holder according to the invention and a pressure measuring capsule during an insertion process according to a first embodiment. Fig. 2 The figure shows the pressure measuring capsule holder according to the first embodiment and the pressure measuring capsule held therein. Fig. 3 shows a pressure measuring capsule holder according to the invention after a modification of the first embodiment. Fig. 4 Figure 1 shows the pressure measuring capsule holder after the modification of the first embodiment and the pressure measuring capsule held therein. Fig. 5shows a pressure measuring capsule holder according to the invention in a second embodiment. Fig. 6 shows the pressure measuring capsule holder according to the second embodiment and the pressure measuring capsule inserted therein. Fig. 7 shows a pressure measuring capsule holder according to the invention in a third embodiment. Fig. 8 shows the pressure measuring capsule holder according to the third embodiment and the pressure measuring capsule inserted therein. Fig. 9 shows a pressure measuring capsule holder according to the invention in a fourth embodiment. Fig. 10 The figure shows the pressure measuring capsule holder according to the fourth embodiment and the pressure measuring capsule held therein. Fig. 11 shows a spring mechanism using the first embodiment as an example. Fig. 12 , Fig. 13 and Fig. 14 Show advantageous variants for attaching a seal using the first embodiment as an example.

[0049] Fig. 1Figure 1 shows a first embodiment of the pressure-measuring capsule holder 1 according to the invention, hereinafter also referred to simply as holder 1, while a pressure-measuring capsule 2, hereinafter also referred to simply as capsule 2, is inserted frontally into it (during an insertion process). The pressure-measuring capsule 2 has a main body 3, which in this example is essentially round and forms a rigid capsule, the interior of which is divided by a membrane 4 for pressure transmission into two chambers, a blood chamber 5 and an air chamber 6. Blood chamber connections 7 are provided on a front face of the pressure-measuring capsule 2 shown in this view, which are adapted to connect the pressure-measuring capsule 2, more precisely its blood chamber 5, to a blood tubing line of an extracorporeal blood treatment machine in a fluid-conducting manner.On the rear side, and not shown here, the pressure measuring capsule 2 has a fluid-conducting air chamber connection 8, preferably conical, in particular a Luer connector, which is connected to the air chamber 6.

[0050] In the following description of the embodiments, it should be noted that the pressure measuring capsule 2, described here as an example and assumed in all embodiments, is inserted frontally into the forward-facing open holder 1. Since the capsule 2 is also round and the associated holder forms at least one correspondingly round recess, the insertion direction is subsequently referred to as the axial direction, and a circumferential direction refers to this round shape. However, it is understandable that the pressure measuring capsule can be designed differently, e.g., cuboid, or can be inserted laterally into the holder without changing the functional principle of the present invention.

[0051] The pressure-measuring capsule holder 1 forms a pot-shaped receiving chamber 9, which is adapted to receive the pressure-measuring capsule 2. The receiving chamber 9 has walls or wall sections 10 on two opposite sides, which form part of a sleeve whose inner circumference essentially corresponds to the outer circumference of the pressure-measuring capsule 2 in order to receive and guide it. The wall sections 10 have two diametrically opposed slots 11 (hereinafter referred to as axial slots) extending in the insertion direction, which are designed to receive the blood chamber connections 7 of the pressure-measuring capsule 2 and thereby ensure a rotationally fixed position of the pressure-measuring capsule 2 relative to the pressure-measuring capsule holder 1.Furthermore, the receiving chamber 9 has two opposing snap hooks or spring hooks 12, offset at an angle (preferably by 90°) to the wall sections 10 and the axial slots 11 provided therein. These snap hooks or spring hooks are elastically bent radially outwards when the pressure measuring capsule 2 is inserted and, when the pressure measuring capsule 2 has reached its final position, spring back or snap into place, engaging an edge of the pressure measuring capsule 2 with hook projections that extend radially inwards. That is, the spring hooks 12 serve as a gripping device.

[0052] The pot-shaped receiving chamber 9 formed by the holder 1 further has a base 13 in which a holder connection 14 (holder connection element / holder connection section), in particular a suitable Luer connector, compatible with the air chamber connection 8 of the pressure measuring capsule 2 (connection section of the capsule), is provided. The holder connection 14 is spring-mounted in the holder 1, in particular in an opening in the base 13 of the holder 1, wherein an associated spring mechanism 15, which will be described in more detail later, is housed in a shaft 16 of the holder 1.

[0053] When the pressure-measuring capsule 2 is inserted into the holder 1, the holder connection 14 and the air chamber connection 8 are connected and pressed tightly together by the spring mechanism 15. Furthermore, the spring mechanism 15 serves to push or eject the pressure-measuring capsule 2 from the receiving chamber 9 when the gripping device or the spring hooks 12 are released, thus acting as an ejection mechanism. The spring travel and spring force of the spring mechanism 15 are dimensioned accordingly. The shaft 16 of the holder 1 also serves to attach the holder 1 to the housing of an extracorporeal blood treatment machine. More precisely, the shaft 16 has a collar for contact with the housing of the extracorporeal blood treatment machine and thus for defining the position of the holder 1 relative to it.

[0054] Fig. 2Figure 1 shows the first embodiment of the pressure-measuring capsule holder 1 according to the invention, into which the pressure-measuring capsule 2 is inserted. It is clearly visible that the blood chamber connections 7 of the pressure-measuring capsule 2 lie in the axial slots 11 of the holder 1 and that the pressure-measuring capsule 2 is thus secured against rotation. Furthermore, it is evident that the spring hooks 12 engage around an edge of the pressure-measuring capsule 2 and thus fix it in position in the axial / insertion direction.

[0055] Fig. 3 and Fig. 4Figure 1 shows a pressure-measuring capsule holder 1 according to a modification of the first embodiment of the invention, both individually and with an inserted pressure-measuring capsule 2. Apart from the modification, this embodiment essentially corresponds to the first embodiment, which is why only the differences are explained below. In contrast to the first embodiment, the pressure-measuring capsule holder 1 shown here has only a single spring hook 12 as a gripping device. Furthermore, only one wall section 10 is provided, which extends around the receiving chamber 9 in a sleeve-like manner and is interrupted only in the area of ​​the spring hook 12. That is, at the point where the second spring hook 12 would be located in the holder 1 according to the first embodiment, a single, continuous wall section 10 is provided.

[0056] Fig. 5Figure 1 shows a second embodiment of the present invention. This largely corresponds to the preceding first embodiment and differs from it essentially in the gripping device and in an associated insertion method, which are explained below. The receiving chamber 9 formed by the holder 1 is surrounded by a circumferential, sleeve-like wall 10 that is unbroken in the insertion / axial direction. On two diametrically opposite sides, the wall 10 forms axial extensions 17. In each of these extensions 17, a slot or circumferential slot 18 is provided, extending in the same circumferential direction (i.e., rotationally symmetrical) and partially around the receiving chamber 9, which serves to receive the blood chamber connections 7 of the pressure measuring capsule 2., the extensions 17 are separated or partially separated from the wall 10 by the circumferential slots 18 in such a way that they form clamps or wings extending circumferentially from the wall 10 at their front end (at a front edge) as the gripping device.

[0057] The circumferential slits 18 are uniformly narrow along their length, optionally widening slightly at their entrances and opening forward / at the end face. In other words, the circumferential slit 18 can extend beyond the associated process 17 into an intermediate section of the wall 10 to form a kind of receiving funnel at the transition between the process 17 and this intermediate section of the wall 10. Furthermore, at their other, closed (sac) end, the circumferential slits each form a rounded, widened connection receptacle 19 or a widening for locking the blood chamber connections 7. Behind the processes 17, on the side of the connection receptacles 19, the wall 10 has a recess 20, which increases the flexibility of the clamps / wings formed by the processes 17.

[0058] To insert the pressure measuring capsule 2 into the holder 1, the pressure measuring capsule 2 is inserted as shown in Fig. 6The blood chamber connections 7 are positioned in / on the receiving chamber 9 such that they lie at the diametrically opposed entrances of the circumferential slots 18 or the receiving funnels formed by them. When the pressure measuring capsule 2 is now rotated circumferentially relative to the pressure measuring capsule holder 1 in a bayonet-like manner, the blood chamber connections 7 slide through the circumferential slots 18. The circumferentially extending clamps formed by the extensions 17 are elastically expanded in the axial direction and may twist slightly. When the blood chamber connections 7 reach the rounded, expanded receptacles 19 of the circumferential slots 18, the elastically deformed clamps reset, thus locking the blood chamber connections 7 into a final position defined by the receptacles 19.During this insertion process, as well as during the reverse process of removing the capsule from the holder 1, the circumferential slots 18 (more precisely, the wall edges of the clamp and a rear wall section enclosing the circumferential slots 18) may serve as a guide track to form at least part of the ejection mechanism according to the invention. Additionally or alternatively, a spring mechanism 15, as will be described in more detail later, is provided on / in the base 13 of the holder as at least part of the ejection mechanism. The spring mechanism 15 and the guide track can also form a combined ejection mechanism.

[0059] Fig. 7 and Fig. 8Figure 1 shows a third embodiment of the present invention. Like the embodiments described above, the holder 1 shown here has a pot-shaped receiving chamber 9. This receiving chamber 9 is formed by an inner sleeve with a bottom 13 and a wall with two diametrically opposed wall sections 10 extending in the insertion / axial direction. Similar to the embodiments described above, the wall sections 10 are equipped with a diametrically opposed liner. Fig. 1Each wall section 10 has an axial slot 11 for receiving the blood chamber connections 7 of the pressure measuring capsule 2. An inner surface of the wall sections 10 serves to receive and guide an outer circumference of the pressure measuring capsule 2. An outer surface of the wall sections 10, on the other hand, serves to rotatably hold and support a locking ring 21 relative to the receiving chamber 9. The locking ring 21 has circumferentially distributed recesses on an outer circumferential surface, which facilitate gripping by the user. The locking ring 21 is a sleeve with two diametrically opposed, essentially L-shaped slots 22, which open in the same direction as the axial slots 11, towards the front edge of the locking ring 21, forming an axial section there.Furthermore, each L-shaped slot 22 has a circumferential section which bends away from the axial section at an angle of 90° or greater and thus extends at least partially in the circumferential direction around the receiving space 9.

[0060] To secure the pressure measuring capsule 2 in the holder 1 of the third embodiment, the locking ring 21 is rotated relative to the receiving space 9 such that the openings / entries of the axial slots 11 and the openings / entries of the axial sections of the L-shaped slots 22 are aligned as shown in Fig. 8The pressure-measuring capsule 2 is shown to be aligned with each other. The pressure-measuring capsule 2 is then inserted into the receiving chamber 9 such that the blood chamber connections 7 lie in the axial slots 11 and the axial sections of the L-shaped slots 22. When the locking ring 21 is now rotated relative to the pressure-measuring capsule 2, the circumferential sections of the L-shaped slots 22 slide over the blood chamber connections 7. In this way, the pressure-measuring capsule 2 is secured against rotation by the axial slots 11 and secured axially by the circumferential section of the L-shaped slots 22.

[0061] Similar to the second embodiment described above, an ejection mechanism can be provided by a spring mechanism 15 located in / on the base 13 of the holder, as will be described in more detail later, and / or at least part of the ejection mechanism can be provided by the circumferential sections 19 of the L-shaped slots 22 being inclined and serving as a guide, as explained above with reference to the circumferential slots according to the second embodiment. The spring mechanism 15 and the guide can also form a combined ejection mechanism.

[0062] Fig. 9 and Fig. 10Figure 1 shows a fourth embodiment of the holder 1 of the present invention, with and without an inserted pressure measuring capsule 2. According to this embodiment, the holder 1 has a base plate, which forms the bottom 13 and in / on which a spring mechanism 15 is provided as an ejection mechanism, in particular a spring mechanism 15 described later, as well as a holder connection 14, which is compatible with the air chamber connection 8 of the pressure measuring capsule 2. In this embodiment, a pluggable connection for quick mounting to a housing is provided on a rear side of the base plate, the base plate being designed to rest against the housing in a mounted state. Furthermore, two opposing wall sections 10 are provided, each of which, in this example, has a flat outer edge flush with the base plate and extends perpendicular to the base plate, i.e., in the insertion direction or axial direction.As in the embodiments described above, the wall sections 10 form a round inner circumferential surface which serves to receive and guide an outer circumference of the pressure measuring capsule 2, and also have axial slots 11 which serve to receive the blood chamber connections 7 of the pressure measuring capsule 2.

[0063] Offset at an angle (by 90°) to the opposing wall sections 10, a hinge bead 23 and a radially outward-facing, spring-loaded latch hook 24 are also provided opposite each other, projecting forward at the edge of the base plate. The hinge bead 23 forms a hinge with a hinge axis running parallel to the base 13 and the edge of the base plate, about which a latch tab 25, articulated to the hinge, is rotatable. The spring-loaded latch hook 24, which is opposite the hinge bead 23, forms, here shown by way of example, an outward-facing snap hook for engagement with the latch tab 22.

[0064] The locking tab 25 essentially forms a frame attached to the hinge with two longitudinal struts 26, which have a bend such that, in the closed state, the locking tab 25 lies roof-like over the base 13, in particular centrally over the pressure measuring capsule 2. Near the bend, the locking tab 25 can provide recesses for receiving the pressure measuring capsule 2 as well as a contact ring 27 for bearing against the capsule 2, in order to secure it, as shown in Fig. 10 The bracket 1 is shown to hold the locking hook 24 against the force of the spring mechanism 15. A crossbar arranged at the free end of the locking tab 25 forms an engagement edge 28 for positively locking the locking hook 24.

[0065] To insert the pressure measuring capsule 2 into the holder 1 according to this embodiment, the locking tab 25 is first opened or pivoted outwards / forwards. The pressure measuring capsule 2 is then inserted into the receiving chamber 9 such that the blood chamber connections 7 are located in the axial slots 11 and the air chamber connection 8 and the holder connection 14 are connected. The user then flips the locking tab 25 so that it, in particular with the contact ring 27, presses against the main body 3 of the pressure measuring capsule 2 to press the capsule against the spring mechanism 15 and establish a gas-tight connection between the air chamber connection and the holder connection 14. In a final position, the crossbar is slid over the locking hook 24 so that it snaps into place over the engagement edge 28 and locks the locking tab 25.

[0066] Fig. 11Figure 1 shows the pressure-measuring capsule holder 1 according to the first embodiment with a pressure-measuring capsule 2 inserted therein in a longitudinal section to illustrate a spring mechanism 15 according to the invention as the ejection mechanism or as part thereof. It is understood that the first embodiment is chosen only as an example and that the same spring mechanism 15 can be arranged equally in the modified first and fourth embodiments, and possibly also in the second and third embodiments, in each case in a base 13, in particular a shaft 16, of the corresponding holders 1.

[0067] In the Fig. 11The bracket shown depicts two diametrically opposed snap hooks or spring hooks 12, which engage around an edge of the pressure measuring capsule 2 inserted into the bracket. The internal structure of the pressure measuring capsule 2 is also shown, including the outer blood chamber 5, the inner air chamber 6, the membrane 4 arranged between them, and one of the blood chamber connections 7. A fluid-conducting air chamber connection 8 is provided on the air chamber 6. When the capsule 2 is inserted, this air chamber connection 8 projects into a shaft 16 of the bracket 1 and has a conical inner surface. The conical inner surface sits on a bracket connection 14 forming an outer cone, which is preferably provided with a soft plastic layer 29, in particular a silicone layer, as a seal (for sealing between the outer cone and the conical inner surface). The bracket connection 14 is mounted on a mechanically stable (deformation-resistant, in particular,A pressure rod 30, preferably made of metal, is mounted on the shaft 16 and together they form a pressure element. The pressure rod 30 extends through the shaft 16 and is axially displaceable within it by means of a spring assembly 31, shown here by way of example as a coil spring. The spring assembly 31 and the pressure rod 30 form the spring mechanism 15 as a (possibly partial) ejection mechanism. The pressure rod 30 has a connection 37 at its inner end, which may project into the housing of the extracorporeal blood treatment machine, e.g., for use with a pressure sensor. Furthermore, the pressure rod 30 and the spring 31 are received in a sleeve that is screwed into the shaft 16 and can thus be easily removed, e.g., for maintenance purposes.

[0068] Fig. 12 , Fig. 13 and Fig. 14The figures also show the pressure measuring capsule holder according to the first embodiment in longitudinal section with further modifications and serve to illustrate various sealing arrangements. Apart from these modifications, it can be assumed that the illustrated holders 1 are essentially identical in construction, which is why only differences are explained below. For example, it is understandable that, although no spring mechanism 15 is shown in these figures for the sake of simplicity, one could nevertheless be implemented accordingly. Fig. 11 a spring mechanism 15 is or may be arranged accordingly therein.

[0069] As in Fig. 12As shown, as an alternative to the soft plastic layer 29 (not shown here), an O-ring 32 can be received as a seal on the outer cone of the mounting connection 14 in an outer circumferential groove, making the seal easier to maintain, and in particular, replace. In this case, a capsule 2 can preferably be used in which the air chamber connection 8 is provided with a straight cylindrical inner surface against which the O-ring 32 rests. This is simpler to manufacture and also allows for a higher axial positional tolerance. Furthermore, if the mounting connection 14 is attached to a pressure rod 30, i.e., arranged on a spring mechanism 15 as (part of) an ejection mechanism, the spring mechanism 15, when the gripping device, in this example the snap hook, is released, acts on the capsule 2 via the frictional force between the O-ring and the straight cylindrical inner surface of the air chamber connection 8 to eject it.If, in the second or third embodiment, no spring mechanism 15 is provided, but only a guide cam 18 / 22 as an ejection mechanism, the outer cone can also be rigidly arranged in the shaft 16.

[0070] In Fig. 13 At the front (facing the inserted pressure measuring capsule 2) a carrier sleeve 33 is inserted at an inlet of the shaft 16, in which an inner circumferential groove with an O-ring 34 inserted therein is provided as a seal, alternatively or additionally to the soft plastic layer 29 described above or the O-ring 32 arranged on the outer cone described above. The in Fig. 13The illustrated O-ring 34 rests against a straight cylindrical outer surface of the air chamber connection 8, thus sealing the air chamber connection 8 against the shaft 16. This is particularly advantageous when the shaft 16 itself forms part of a pressure transmission line between the capsule 2 and the pressure sensor and can be provided in embodiments both with and without a spring mechanism 15 as an ejection mechanism. However, the claimed invention only claims a pressure measuring capsule holder with a spring mechanism 15 as an ejection mechanism.

[0071] In Fig. 14 is different from Fig. 13No carrier sleeve 33 is provided as a carrier for the O-ring 34; instead, an O-ring 35 is provided in an outer circumferential groove on a straight cylindrical outer surface of the air chamber connection 8 and rests sealingly against a straight cylindrical inner circumferential surface of the shaft 16. This can be achieved according to the modification explained above. Fig. 13 in embodiments with and without spring mechanism 15 and in particular provided with a shaft 16 acting as a pressure transmission line, is in contrast to the modification according to Fig. 13 However, it is easier to manufacture and maintain. The claimed invention, however, only claims a pressure measuring capsule holder with a spring mechanism 15 as an ejection mechanism. Reference character list

[0072] 1 Pressure measuring capsule holder 2 Pressure measuring capsule 3 Main body 4 Membrane 5 Blood chamber 6 Air chamber 7 Blood chamber connection 8 Fluid / air chamber connection 9 Receiving chamber 10 Wall / Wall section 11 Slot / Axial slot 12 Snap hook / Spring hook (Gripping device) 13 Base 14 (Holding) connection element 15 Spring mechanism (Ejection mechanism) 16 Shaft 17 Extension / Clamp (Gripping device) 18 Slot / Circular slot (Guide track, Ejection mechanism) 19 Connection receptacle 20 Recess 21 Locking ring / Rotary lock (Gripping device) 22 L-shaped slot (Guide track, Ejection mechanism) 23 Hinge bead / Hinge (Gripping device) 24 Locking hook (Gripping device) 25 Locking tab (Gripping device) 26 Longitudinal struts 27 Mounting ring 28 Entry edge 29 Soft plastic layer 30 Pressure rod 31 Spring 32 O-ring (seal modification) 33 Carrier sleeve 34 O-ring (seal modification) 35 O-ring (seal modification) 36 Pressure transmission line 37 Connection

Claims

1. A pressure cell holder (1), which is attachable to a housing of an extracorporeal blood treatment machine, in particular a dialysis machine, with a gripping device (12; 17; 21; 23, 24, 25) adapted to grip around or engage a pressure cell (2) that is insertable into the pressure cell holder (1), which pressure cell has at least one blood chamber port (7) and whose interior space is separated by a membrane (4) into a blood chamber (5) and a fluid chamber (6), and with a pressure transmission line (36), which is configured to be fluidically connectable to the fluid chamber (6) of the pressure cell (2) and to transmit a fluid pressure present in the fluid chamber (6) to a pressure sensor of the extracorporeal blood treatment machine, the pressure cell holder (1) having an ejection mechanism (15; 18; 22) adapted to eject the pressure cell (2) upon release of the gripping device (12; 17; 21; 23, 24, 25), and the ejection mechanism (15; 18; 22) comprising a spring mechanism (15) having a pressure element (30) which is spring-mounted in such a way that it is pre-tensioned upon insertion of the pressure cell (2) and presses against the pressure cell (2) in a holding state in which the pressure cell (2) is held by the gripping device (12; 17; 21; 23, 24, 25), wherein at an outer end of the pressure element (30), a holder port element (14) comprising the pressure transmission line (36) is arranged or formed.

2. The pressure cell holder (1) according to claim 1, characterized in that the gripping device (12; 17; 21; 23, 24, 25) is mountable on the housing via a shaft (16), the pressure element (30) being received in the shaft (16) and being spring-mounted.

3. The pressure cell holder (1) according to claim 2 or 3, characterized in that the holder port element (14) is conical, preferably made of a soft plastic, further preferably formed as a Luer connector.

4. The pressure cell holder (1) according to claim 1, characterized in that a spring force of the spring mechanism (15) is set to press the pressure element (30) in the holding state against the pressure cell (2) in such a way that a gas-tight connection is provided between the pressure cell (2) and the pressure transmission line (36).

5. The pressure cell holder (1) according to any of the preceding claims, characterized in that at least one wall portion (10) is provided which at least partially defines a receiving chamber (9) for receiving the pressure cell (2).

6. The pressure cell holder (1) according to claim 5, characterized in that the at least one wall portion (10) is provided with a slit (11; 18) for receiving the at least one blood chamber port (7) of the pressure cell (2).

7. The pressure cell holder (1) according to claim 5 or 6, characterized in that an inner circumferential surface of the at least one wall portion (10) is formed to serve as a guide for the pressure cell (2).

8. The pressure cell holder (1) according to any of the preceding claims, characterized in that the gripping device forms at least one snap-fit hook (12) which is designed to engage behind the pressure cell (2) when the pressure cell (2) is inserted.

9. The pressure cell holder (1) according to any of claims 6 and 7, characterized in that the at least one slit is a circumferential slit (18) extending transversely to the insertion direction along the corresponding wall portion (10), through which the gripping device is separated or formed as at least one elastically bendable clamp (17) extending parallel to the circumferential slit (18) at one front end of the wall portion (10) of the pressure cell holder (1), wherein the at least one blood chamber port (7) is insertable into the circumferential slit (18) by rotating the pressure cell (2).

10. The pressure cell holder (1) according to claim 10, characterized in that the at least one circumferential slit (18) is widened at one end to provide a latchable port receptacle (19).

11. The pressure cell holder (1) according to claim 10, characterized in that a setback (20) is provided at a front edge of the at least one wall portion (10), next to an attachment point of the clamp (17).

12. The pressure cell holder according to any of claims 6 and 7, characterized in that the gripping device comprises a sleeve-shaped turning bolt (21) rotatably mounted on an outer side of the at least one wall portion (10) and having at least one L-shaped slit (22), having an axial portion which opens axially against an insertion direction (9) on a front face of the turning bolt (21) and which, in an open position of the turning bolt (21), overlaps the at least one axially extending slit (11) provided in the wall portion in such a way that the at least one blood chamber port (7) is insertable into the respective L-shaped slit (22) and axial slit (11), and a circumferential portion which forms a circumferentially extending slit end and is adapted to hold the at least one blood chamber port (7) in a fixed position together with the axial slit (11) in a closed position achievable by turning the turning bolt (21).

13. The pressure cell holder (1) according to any of claims 9 to 12, characterized in that the ejection mechanism has a guide link with a slit running obliquely to an insertion direction, in particular to the circumferential slit (18) or to the circumferential portion of the L-shaped slit (22).

14. The pressure cell holder (1) according to any of claims 1 to 7, characterized in that the gripping device forms a locking tab (25) attached or displaceably mounted via a hinge-like joint (23) in such a way that, in a closed position, the locking tab extends over the pressure cell (2) on a side opposite the spring mechanism (15) in order to press and hold the pressure cell (2) against the spring mechanism (15).