MEDICAL DEVICE WITH A VALVE SEAT FOR A REMANENT CHECK VALVE

Description

[0001] The present invention relates to a medical functional device having the features of claim 1.

[0002] In medical or laboratory technology, disposable subsystems are increasingly designed as compact medical functional devices such as cassette systems or blood cassettes in which liquids and gases, especially medical liquids and blood, are guided in channels and chambers.

[0003] The functional element of the check valve is often used in such cassette systems, but also as a single arrangement inserted into hoses, to block the flow of fluids passively, i.e. without the presence of actively driven valves, in the desired counterflow direction and to release it in the desired flow direction, often only above a certain opening pressure.

[0004] Some disposable cassettes (also referred to as single-use cassettes) from the applicant of the present application essentially consist of a rigid part manufactured by injection molding with fluid-conducting structures and a film. After being pressed, bonded, or welded to the rigid part, the film seals half-open rigid part channels and chambers in a liquid-tight manner. In addition to its sealing function, the film's flexibility and thin wall thickness also enable the measurement of parameters such as temperatures, pressures, and fill levels, the detection of air and blood, and the actuation of valves and check valves through the film.Such check valves can be used in such cassettes to prevent the backflow of contaminated dialysis fluid into the hydraulic or water section of the treatment machine (in short: machine), to prevent the leakage of blood via the arterial heparin Luer connection and the venous addition Luer connection in the event of malfunctions of the machine or incorrect operation by the user, to prevent the penetration of air into the cassette below a given opening pressure (negative pressure to the environment) and to prevent the flow of contaminated residual fluids into the environment when dismantling the disposable.

[0005] Most disposable systems require sterilization. Depending on the disposable materials, in addition to gamma and e-beam radiation treatments, gas treatments such as ETO, steam-vacuum, and H2O2 sterilization are also used. With gas sterilization, the problem is that surfaces in direct contact and blocked or restricted flow paths can make sterilization difficult or impossible. To ensure gas sterilizability, some check valves therefore have a first, initial, open-flow "initial" position. When the treatment device is upgraded using the cassette, the check valve is moved from this initial position to a second position, the so-called "activated" position. Only from this transition, referred to here as "activation," does the valve perform the check function, but not beforehand.Such an activatable check valve is disclosed, for example, in the published patent application DE 10 2009 024 469.7, filed on June 10, 2009, with the German Patent and Trademark Office for the applicant of the present application.

[0006] The above-mentioned activatable check valve is activated after the blood cassette has been installed in the dialysis machine when the machine door is closed. Activation occurs when the check valve is pushed into the valve seat of the cassette by means of a protrusion protruding from the actuator-sensor unit, while indenting the disposable film, until the annular sealing seat areas of the elastomer component and the hard component come into contact with one another with preload. This causes the valve to leave the fluid-open initial position (also referred to herein as the first position) and assume the check valve position (also referred to herein as the second position). The clamping-centering ribs of the elastomer component have only a slight oversize compared to the corresponding clamping-centering bore in the hard part. This initially ensures safe gas sterilization. The reliable check function is then activated.

[0007] The object of the invention is to propose a further medical functional device with at least one check valve (also referred to herein as a check valve arrangement).

[0008] The problem can be solved by a medical functional device having the features of claim 1.

[0009] According to the invention, a medical functional device with a valve seat for a check valve, also referred to as a check valve arrangement or simply as a valve, is proposed.

[0010] The check valve is designed to assume a second functional position in addition to a first position suitable for gas sterilization, in which a sterilization gap remains. This occurs by applying a force to a section of the check valve and / or by displacing the section. The first functional position is also referred to herein as the initial position or sterilization position. The second functional position is also referred to herein as the activated position or check position.

[0011] In the second functional position, the check valve performs a check function, wherein the check valve is designed to remain in the second position after the force has been removed after it has been transferred into the second position.

[0012] After the transferring force is removed or after the displacing actuator is released from the check valve, the check valve exhibits no, or at least not sufficient, return action to move the check valve from the check position back to the sterilization position. The check valve can be described as self-locking.

[0013] The transition from the first position to the second position is also referred to herein as "activation".

[0014] A check valve that remains in the second position even after the force that caused the transition from the first to the second position has been removed is also referred to herein as "remanently activated." A valve suitable for this purpose is therefore also considered and / or referred to herein as "remanently activatable."

[0015] In all the following statements, the use of the expression "may be" or "may have" etc. is to be understood as synonymous with "is preferably" or "preferably has" etc. and is intended to explain an embodiment of the invention.

[0016] Whenever numerical terms are mentioned herein, the person skilled in the art will understand them as indicating a numerical lower limit. Unless this leads to a contradiction recognizable to the person skilled in the art, the person skilled in the art will therefore always read "at least one" or "at least one" when referring to "a" or "an." This understanding is encompassed by the present invention, as is the interpretation that a numerical word such as "a" can alternatively be meant as "exactly one," wherever this is recognizably technically possible to the person skilled in the art. Both are encompassed by the present invention and apply to all numerical terms used herein.

[0017] Advantageous further developments of the present invention are each the subject of subclaims and embodiments.

[0018] Embodiments of the invention may comprise one or more of the features mentioned below in any combination.

[0019] In all embodiments according to the invention, the cap can be designed as a snap-in cap.

[0020] In some exemplary embodiments of the functional device according to the invention, the valve is generally actuated by applying a path / displacement. The force mentioned here is then a reaction to this.

[0021] In some exemplary embodiments of the functional device according to the invention, the check valve has no check function in the first position.

[0022] In some exemplary embodiments of the functional device according to the invention, the check valve is designed to be moved from the first position to the second position by means of an actuator of a blood treatment device. The functional device is connected to the blood treatment device for its operation.

[0023] In some exemplary embodiments according to the invention, the functional device is designed such that the check valve remains in the second position due to frictional engagement after the force is removed. For this purpose, an element can be provided that ensures a frictional engagement, for example, between at least one section of a valve body and at least one section of a valve seat. This element can be referred to as a frictional engagement element.

[0024] In some exemplary embodiments of the functional device according to the invention, the check valve comprises or consists of a valve body and / or a cap, which, whenever mentioned herein, can optionally be configured as a snap-in cap; in these embodiments, the valve seat is not part of the check valve. In other exemplary embodiments according to the invention, however, the valve seat is also part of the check valve.

[0025] In certain exemplary embodiments according to the invention, the functional device is designed such that the check valve remains in the second position only by frictional engagement after the force is removed.

[0026] In certain exemplary embodiments according to the invention, the functional device is designed such that the check valve (or the valve body and / or the cap) is moved relative to the valve seat or the remaining functional device during or for transferring the check valve from the first position to the second position. The movement relative to the valve seat can occur in a direction that is preferably completely or substantially perpendicular to the film plane.

[0027] In certain exemplary embodiments according to the invention, the functional device is designed such that the cap, if present, does not move relative to the valve seat when the check valve is opened.

[0028] In some exemplary embodiments of the functional device according to the invention, the check valve has a valve body and a cap or locking cap manufactured separately therefrom.

[0029] In some exemplary embodiments of the functional device according to the invention, the valve body has a number of nubs. These protrude radially outward from openings in the cap after the valve body is connected to the cap.

[0030] In certain exemplary embodiments of the functional device according to the invention, both the valve body and the cap have drainage structures.

[0031] In some exemplary embodiments of the functional device according to the invention, a step or a step-like diameter reduction is formed within the cylindrical section of the valve seat of the cassette in the retaining ring area of ​​the cassette.

[0032] In some exemplary embodiments of the functional device according to the invention, the valve seat and / or the sealing section are conical or flat in the sealing area. The valve body and / or the cap seal against this in the second position.

[0033] In certain exemplary embodiments of the functional device according to the invention, the valve body is seated in the cap radially under a first preload and axially under a second preload. The second preload can be greater than the first.

[0034] In some exemplary embodiments of the functional device according to the invention, the valve body has the shape of a cup with a valve base and optionally a tie rod that is centrally and, for example, rigidly connected to the valve base. The tie rod is designed to connect the valve body and the cap by snapping the tie rod into a locking opening in the cap or locking cap.

[0035] In some exemplary embodiments of the functional device according to the invention, the cap has tongues which extend radially.

[0036] In certain exemplary embodiments of the functional device according to the invention, the tie rod and a valve base are designed to be sufficiently rigid so that the tie rod in the cap, in the second position, maintains a contact-free distance from other sections in all spatial directions.

[0037] In some exemplary embodiments of the functional device according to the invention, the tie rod and the valve base are designed to be sufficiently rigid so that the tie rod, in the second position, maintains a contact-free distance in the cap from all sections in all spatial directions.

[0038] In some exemplary embodiments of the functional device according to the invention, the cap has the shape of a dome with several openings open radially outward and axially at the top. Furthermore, locking tongues are arranged in the openings, which, when bent radially inward, only partially close the openings.

[0039] In certain exemplary embodiments of the functional device according to the invention, the number of openings and locking tongues is odd.

[0040] In some exemplary embodiments of the functional device according to the invention, the check valve is designed to remain in the second position after being transferred into the second position, on the one hand, and after the force is removed or after the displacing actuator is released from the check valve, on the other hand, due to locking, jamming, wedging, or the like of components of the check valve with one another. The components can be the valve body and the cap, wherein the valve body is elastically deformed and locks, jams, wedges, or the like in the cap upon application of the force or by means of the displacing actuator.In certain embodiments according to the invention, it is a retaining ring of the valve body which locks, wedges, clamps or the like behind or under sections of the cap, such as the optional support tongues of the cap, while a further section of the valve body, such as an optional centering cone thereof, presses against a further section of the cap, such as an optional cone receptacle, under the action of a spring element.

[0041] In certain exemplary embodiments of the functional device according to the invention, the spring element is designed as an elastic section, preferably of the valve body. The spring element can be a spring membrane. The spring membrane can be circumferential and / or rotationally symmetrical. The spring membrane can have a cup-shaped section in a cross-section. The spring membrane can have concentric sections in a cross-section.

[0042] In some exemplary embodiments of the functional device according to the invention, the check valve or a portion thereof is designed to cause a preload of the check valve inserted into the valve seat or at least a portion thereof.

[0043] In some exemplary embodiments of the functional device according to the invention, the preload is effected by means of a spring element, which is designed, for example, as a spring membrane.

[0044] In some exemplary embodiments of the functional device according to the invention, the spring element is a portion of the valve body.

[0045] In some exemplary embodiments of the functional device according to the invention, the cap has a circumferential edge. This edge is located at the level of the locking tabs and forms the main parting plane of the injection molding tool. In certain embodiments according to the invention, the circumferential edge can cause the cap to deviate from the cylindrical shape, which can advantageously prevent the cap from tilting or jamming when the cap is tilted or subjected to tilting movements.

[0046] In some exemplary embodiments of the functional device according to the invention, a circumferential gap remains in the first position, referred to here as the sterilization gap. This axial installation position and thus the sterilization gap are maintained by frictional engagement between contacting components, preferably between the valve seat on the one hand and the valve body on the other, for example in the form of clamping centering ribs as an example of a frictional engagement element. Sterilization fluid can flow through the sterilization gap in the first position. In the second position, it is preferably closed or no longer exists.

[0047] In certain exemplary embodiments according to the invention, the functional device is designed as a blood cassette, cassette, blood tube or infusion tube.

[0048] In some exemplary embodiments according to the invention, the functional device is designed as a blood cassette comprising a hard body and a film covering the hard body or parts thereof. The valve seat is provided in the hard body. The check valve is arranged to be moved into the second position by pressure or displacement of an actuator of the blood treatment device on the film.

[0049] In some exemplary embodiments of the functional device according to the invention, the foil-side end face of the check valve does not protrude beyond the foil plane of the blood cassette.

[0050] In certain embodiments of the invention, a one-piece valve body is made of silicone rubber. The valve body can have a preferably cup-shaped radial sealing ridge, which is connected circumferentially to a core cylinder in a fluid-tight manner.

[0051] In certain embodiments of the invention, the valve body has guide-clamp-drainage ribs that serve for guiding, clamping, and drainage. These ribs are preferably connected to the core cylinder in even and odd-numbered spacing, preferably in more than two.

[0052] In certain embodiments according to the invention, the valve seat can have two adjacent cylinders, here as a guide cylinder (at the bottom in the valve seat) and a sealing cylinder (at the top around the valve seat), wherein the sealing cylinder has a larger diameter than the guide cylinder, and wherein the area of ​​the diameter transition or jump between the two cylinders is referred to as a detent step. At least some of the clamping guide knobs of the valve body or the guide clamping drainage ribs rest on the guide cylinder in the first position, and the clamping detent knobs, which protrude radially beyond the aforementioned clamping guide knobs, rest on the sealing cylinder in the first position. Both the clamping detent knobs and the aforementioned clamping guide knobs rest on the guide cylinder in the second position.

[0053] In certain embodiments of the invention, a radial sealing land of the valve body is axially disengaged from the sealing cylinder, creating a flow-open annular volume (a sterilization gap). Only upon application of a minimum axial activation force (preferably 20 to 40 N) to the end face of the core cylinder does an axial displacement movement begin.

[0054] In certain embodiments of the invention, drainage foot ribs rest on a lower section, for example, the base, of the guide cylinder in the second position. They can thus limit the possible activation stroke and, together with all other ribs, ensure uniform venting and flow around the valve body, as well as safe sterilization using gases.

[0055] In certain embodiments of the invention, a circumferential radial sealing ridge with a preferably tapered sealing edge, together with the sealing cylinder of the valve seat of the cassette, forms a check valve sealing system after the activation stroke has been executed. The circumferential sealing edge of the – preferably elastomeric – valve body rests against the sealing cylinder under radial preload.

[0056] In certain embodiments of the invention, the valve body is made of an elastomeric material, preferably silicone rubber.

[0057] In certain embodiments according to the invention, a positioning ring of the valve body has a plurality of drainage structures, preferably arranged circumferentially, which ensure accessibility for sterilizing gases when installed.

[0058] In certain embodiments of the invention, an upper annular end face of the positioning ring is flush with the film or the cassette edge onto which the film is placed or welded.

[0059] In certain embodiments of the invention, an outer surface of the positioning ring has a larger diameter than the associated shoulder hole in the cassette. The friction-induced holding force in the cassette can be determined by the diameter difference, the material hardness, and / or the design of the drainage structures.

[0060] In certain embodiments of the invention, a lower annular end face of the positioning ring serves as a movement stop and thus for calibrating the opening pressure and the passage characteristic in the second position ("activated").

[0061] In certain embodiments of the invention, a passage ring zone consists of individual, loop-shaped, wound webs with gaps between them. It serves to allow fluid passage in the second position, holds the valve core in the desired position, and forms an axially resilient support structure that compensates for misalignment.

[0062] In certain embodiments of the invention, the valve body comprises a – preferably mushroom-shaped – valve core. The latter has a – preferably stiffer – core region that acts as a movement limiter in both axial directions, i.e., on its upper side against the film and on its underside against a tappet on the cassette side.

[0063] The stops are only contacted when the specified pressure and flow rate range is exceeded. In the first position, a sealing ring zone of the valve has an annular gap – for example, approximately 0.4 mm – for reliable gas sterilization. In the second position, however, it seals – preferably with a minimum preload of approximately 0.4 mm – against a sealing seat of the valve – for example, a conical or flat one.

[0064] In certain embodiments of the invention, the check valve assembly comprises or consists of a valve body with a cap. The cap is preferably made of thermoplastic, preferably polypropylene (PP for short).

[0065] In certain embodiments according to the invention, the valve body, which has a sealing ring, has a number of knobs which, after pre-assembly of the valve body with the cap, project radially outwards from openings in the cap.

[0066] In certain embodiments of the invention, both the valve body and the cap have drainage structures. These serve to ensure optimal gas and steam sterilizability.

[0067] In certain embodiments of the invention, a step (step-like diameter taper) referred to as a diameter shoulder is provided within the cylindrical section of the cassette's valve seat in the retaining ring area of ​​the cassette. Activation or the second position is achieved when the radially protruding nubs have been pushed beyond the diameter shoulder into the cassette's valve seat and / or when an annular end face of the cap has approached the annular end face of the cassette's valve seat until they are in flat contact.

[0068] In certain embodiments of the invention, the cap is designed to be stiffer than the valve body.

[0069] In certain embodiments of the invention, the check valve assembly of the invention may be in two parts.

[0070] In certain embodiments of the invention, the check valve assembly according to the invention can provide a flat seal. In certain embodiments of the invention, "flat" means that the sealing surface is—preferably entirely, substantially, or partially—flat and / or parallel to a film plane. In some embodiments of the invention, with a flat-sealing arrangement, the sealing surface can lie—preferably entirely or substantially—in a plane perpendicular to the direction of displacement of the valve body.

[0071] In certain embodiments of the invention, the valve seat against which the valve body and / or the cap seals in the second position is conical in the sealing area or conical in section.

[0072] In certain embodiments of the invention, the valve body has the shape of a cup with a bellows-like shell, a valve base—optionally largely flat and rigid—and optionally a tie rod centrally and rigidly connected to the valve base. The tie rod is designed to connect the valve body to the cap, for example, by snapping the tie rod into a matching central locking opening in the cap.

[0073] In certain embodiments according to the invention, the annular end of the bellows skirt facing away from the valve base sits in the cap radially under—preferably—a slight preload and axially under a greater preload than radial. The bellows skirt is compressed accordingly, and the axial preload is maintained via the engaged tie rod. This axial preload can be referred to herein as the preload of the check valve.

[0074] In certain embodiments according to the invention, the cap is made of the relatively stiff material PP (flexural modulus of elasticity approx. 1750 N / mm).

[0075] In certain embodiments of the invention, the cap is designed with radially resilient tongues.

[0076] In certain embodiments according to the invention, the tie rod and the valve base are designed to be sufficiently rigid so that the tie rod, in the second position, maintains a contact-free distance from the construction environment in the cap in all spatial directions.

[0077] In certain embodiments according to the invention, the cap or locking cap (both terms are to be understood as interchangeable, as long as the cap is designed to be lockable in the respective embodiment) additionally has a plurality of radially inwardly projecting or protruding retaining lugs on a lower annular end.

[0078] In certain embodiments of the invention, the cap is designed so that it can be manufactured in a multiple on-off injection molding tool with central hot runner gates.

[0079] In certain embodiments of the invention, the valve body has a central conical mandrel which is received without play in a corresponding cone of the cap.

[0080] In certain embodiments of the invention, a connecting membrane or diaphragm extends between the cone and a retaining sealing ring of the valve body.

[0081] In certain embodiments according to the invention, the valve body has a slight downward curvature of its centrally arranged connecting membrane in the non-installed state, ie in the assembled state in the direction of the valve seat of the medical functional device.

[0082] During pre-assembly of the valve body in the cap, this curvature is already neutralized in certain embodiments of the invention by snapping a support flange of the valve body into place until it meshes with the retaining lugs of the cap, or the connecting membrane is elastically deformed so that a slight curvature in the opposite direction, i.e., upwards, away from the valve seat, is created. In certain embodiments of the invention, the curvature in the opposite direction is further increased upon activation or during the transition to the second position, and in certain embodiments of the invention, a further increase during flow of treatment fluids.

[0083] In certain embodiments of the invention, the retaining sealing ring is designed to be more compact and / or thicker-walled in relation to the connecting membrane.

[0084] In certain embodiments of the invention, the check valve arrangement has the shape of a mandrel plate-in-cap.

[0085] In certain embodiments of the invention, the valve seat has no undercuts.

[0086] In certain embodiments according to the invention, the cap has the shape of a dome with several openings that are open radially outward and axially upward. Locking tabs that can be bent radially inward are arranged in these openings. The locking tabs only partially close the openings, for example, approximately 30%.

[0087] In case of doubt, spatial information such as "above", "below", etc. refers to the representation as shown in the figures attached here.

[0088] In certain embodiments of the invention, the number of openings and the number of locking tongues are preferably each odd.

[0089] In certain embodiments according to the invention, the cap has a circumferential, preferably sharp edge, which is preferably at the same height as both the support arches and the flexible locking tongues and thereby forms the main parting plane of the injection molding tool.

[0090] In certain embodiments of the invention, an upper cap ring face forms the highest section of the vault construction and represents the mechanical interface through the film for introducing the activation force, activation path, and holding force by the actuator-sensor unit of the treatment machine. It represents a flat ring face interrupted by structuring grooves.

[0091] In certain embodiments according to the invention, the cap has numerous structures such as structuring grooves, notches and recesses both on the upper annular face and in the area of ​​the cone receptacle.

[0092] In order for the component to retain a symmetrical shape that is not susceptible to distortion when the thermoplastic cools during production, in certain embodiments according to the invention the outer and inner structures are arranged in a concentric and equal or even numbered number in relation to the number of openings or locking tongues.

[0093] In certain embodiments according to the invention, the cap has not only the vault structure, but also vertical cylinder walls and conical, in particular steeply conical, circumferential walls, preferably inside and outside a cap centering groove.

[0094] In certain embodiments according to the invention, the valve body has a rolling bellows-like shape and comprises a centering cone, a stop face, at least two auxiliary centering bosses, a resilient connecting membrane, a sealing ring and a retaining ring or consists of these, the above terms being used with reference to Fig. 6 explained below.

[0095] In certain embodiments according to the invention, in order to further increase the possibility of insertion, both the lower annular end of the cap and the valve seat edge on the foil web are provided with rounded portions which act as additional insertion bevels.

[0096] In certain embodiments of the invention, the locking tongues have a diameter that is, for example, 0.4 mm larger than the outer cylinder walls of the cap.

[0097] In certain embodiments according to the invention, the valve body is pre-tensioned in the cap and installed in a force-locking and form-fitting manner without axial play.

[0098] Some or all embodiments of the invention may have one or more of the advantages mentioned above or below.

[0099] In some embodiments according to the invention, the activation, ie the check function, can advantageously be retained even after the disposable has been dismantled. This allows the leakage of liquid at the three mentioned locations to be prevented even during dismantling by means of the inventive, remanently activated check valves. This eliminates the need for two hose clamps on the disposable and the user's action required to activate them. Furthermore, there is advantageously no need for a closure sleeve in the substituate connector (see reference numeral 41 in Fig. 1 of WO 2010 / 121819 A1) and an associated working stroke of the machine to provide protection against contamination by liquids escaping from the cassette.

[0100] The check valves according to the invention can advantageously provide the required robustness against premature activation in production before sterilization.

[0101] Furthermore, embodiments according to the invention can offer advantages in automated production, reliable sterilization, and improved quality of the check valve functions. Large-lumen drainage structures contribute to smooth films and smooth injection-molded walls, as well as a low proportion of flat component contact. Furthermore, they ensure a secure retention in the initial open position, i.e., the first position, until completion of gas sterilization. They also ensure minimal and defined changes in properties due to gas sterilization, particularly in the opening pressure. They minimize changes in the properties of the installed check valves due to mechanical, thermal, or radiation-induced stress during storage and transport, which could impair the process of safe and precise activation during the setup process.Avoidance of the previously tolerated protrusion of the film-side end faces of the check valves beyond the film plane of the cassette (check valves cause local dents in the film) to ensure a reliably produced film weld seam, starting from a film that rests flat on the cassette throughout; more tolerance-tolerant design of the individual parts and their interaction both during assembly and in interaction with the treatment machine, while simultaneously ensuring high reproducibility of the tightness, the opening pressure, and the flow-pressure drop characteristic curve, thus ensuring reliable function even in large-scale production and with many or older treatment machines on the market; increasing the reproducibility of the opening pressure; reducing the pressure drop in the passage area, thus minimizing the pressure drop at any passage volume flow; flattening of the volume flow-pressure drop-flow characteristic curve;i.e., minimizing the increase in pressure drop with increasing passage volume flow, increasing fine and long-term intrusion tightness below the passage opening pressure, especially tightness against air intrusion, reducing sensitivity to leaks in the presence of contaminant particles and improving self-cleaning ability, continuing to provide secure and tight sealing in the barrier area up to the maximum pressure, and avoiding vibrations and noise emissions.

[0102] Other benefits include: ∘ low risk of malfunction after activation; ∘ reliable operation even with the maximum possible axial activation stroke (measured on the film) of approximately 1.2 mm, which is predetermined by the cassette design and the treatment device; ∘ improvement of the fluidic characteristics can be achieved due to improved design and smaller tolerances in components and activation; ∘ reversible activation can be carried out during production for functional testing; ∘ no problem of uneven injection molding with weld lines and associated leaks; ∘ sufficiently consistent geometry after steam sterilization; ∘ negligible relaxation during the preloaded activated position, which could reduce the valve preload during use and thus influence the opening pressure and passage pressure drop parameters;∘ High tolerance bridging due to the material combination of elastomer and thermoplastic and due to nub geometries, thus cost-effective and safe production with large permissible dimensional tolerances; ∘ Safe axial force limitation, as it is made entirely of elastomer and has axially flexible base ribs; ∘ Good gas sterilizability due to large-lumen drainage and the convexity of the clamping and centering ribs, small pressing surfaces between the valve body and valve seat; ∘ Response pressure and pressure-volume flow characteristic curve depend only on the selected materials, the selected wall thicknesses and diameters and on the manufacturing tolerance of the dimensions and material properties, but not on the size of the activation stroke, provided the effective activation stroke is within the planned range (here 1.2 to 1.8 mm); ∘ No undercuts and therefore no demolding problems when designing the valve seats in the cassette∘ Continued one-piece check valve with low risk of malfunction after activation; ∘ Simple assembly process; ∘ Good tolerance compensation against axial installation misalignment; ∘ Decoupling of the activation path and thus the valve preload from the machine tolerances; ∘ Significant improvement in the reproducibility of opening pressure and pressure-volume flow characteristic curve; ∘ Flattening of the pressure-volume flow characteristic curve; this enables lower pressure losses and a lower design opening pressure; ∘ Ergonomic advantages due to lower syringe actuation force during drug infusion; ∘ Reduced hemolysis when used for blood infusion; ∘ Simple pre-assembly of the valve in the snap-on cap or cap with high reproducibility of radial centering; ∘ Possibility of testing the valve assembly for functionality during production after installation of the cassette foil∘ the bellows shape of the valve allows a more linear spring characteristic to be achieved than, for example, with the simple mushroom shape; ∘ the sealing ring area of ​​the valve element is not located at the end of the flow path in relation to the flow conditions when manufactured as an LSR injection-molded part (Liquid Silicon Rubber) (as is the case with the simple mushroom shape), thus avoiding weld lines and thus shape defects that cause leaks; ∘ very little material, cost-effective implementation of the check valve (0.5 euro cents); ∘ rotation-position-free, easily automated assembly of the valve assembly; ∘ good centering behavior of the sealing ring area; ∘ reliable avoidance of friction between valve and cap during activation and flow through; ∘ axially particularly small valve arrangement with thus reducible flow dead spaces; ∘ advantages in characteristics and tolerance behavior like the other preloaded valve types with cap∘ Gas-open initial position to ensure safe gas sterilization processes; ∘ Robust initial position with high trigger threshold force despite short activation travel; ∘ Prevention of the escape of unwanted fluids after disarmament through remanent activation; ∘ Safe remanent activation during arming with secure position retention after disarmament through frictional engagement and large preload travel of the activated valve; ∘ Hard covering cap encapsulates the soft valve against mechanical interference; ∘ New locking tongue-wedge-diameter shoulder mechanism for robust gas-open initial position and defined, greatly increased trigger threshold force; ∘ Extremely short activation travel in relation to the valve diameter enables passive activation actuators on the machine side with a flat film initial position and low film tensile stress.∘ new tilt-proof activation or sliding bearing mechanism with deliberate inclusion of possible tilting in the regular displacement behavior; ∘ special geometric arrangements with reduced tolerance chains; ∘ reduced tolerances through more precisely manufactured, small-scale, function-determining geometries; ∘ reduction of valve tolerances through mutual geometric calibration of assembled components; ∘ use of thermal and temporal material stress relief through sterilization and storage to calibrate the activation threshold force and reduce it during treatment, but to set it as high as possible during valve production; ∘ decoupling of the position tolerances of the valve to the valve seat from the introduced forces and paths of the treatment machine by interposing the cap;∘ The preload principle leads to a greater preload travel and consequently to more precise valve properties with lower pressure losses and therefore less impact on the treatment fluid (lower shear stresses at the same volume flow); ∘ Conical or spherical cap-shaped valve sealing seats lead to valve properties with closer tolerances, increased sealing when stationary, self-cleaning capabilities, and better sealing capabilities in the event of foreign bodies and local material defects; ∘ Globally stiff and locally pointed and soft valve sealing ring geometries lead to better sealing capabilities in the event of foreign bodies and local material defects; ∘ Extremely low manufacturing costs for the individual components thanks to open-close demolding principles and minimized injection molding cycle times thanks to uniform wall thicknesses and low material consumption and, due to low tensile stress, the possibility of using a film with a relatively low elastomer content and therefore a low cost.∘ Specifically more precise component geometry through rotationally symmetrical, specifically stiff geometry and central gating; ∘ No or hardly any air inclusions and weld lines in the sealing ring zone due to geometric shifting away from the end of the flow path; ∘ Fully automatable manufacturing and testing concept conceptually planned into the part geometries, taking into account all part and handling tolerances, with particularly good self-centering properties and freedom from rotary positioning of all components; ∘ Complete fluidic testing of the valve in the fully installed state can be implemented through reversible activation; ∘ Self-compensating properties against characteristic curve relaxation during operation; ∘ Use of rolling bellows-specific deformation properties to flatten the pressure loss-volume flow characteristic curve∘ Optimized drainage and sterilization structuring of the thermoplastic cap as a functional improvement compared to structuring of the elastomer valve component; ∘ Conical centering with a large opening angle, axial structuring, matte erosion, and axial stop zones on the cap for optimized assembly functionality with the soft, sticky elastomer material of the valve; ∘ Possibility of setting the opening pressure to a lower value due to higher reproducibility while maintaining the same level of safety, thus enabling more ergonomic injection of treatment fluids, lower pressure levels of supply pumps that are gentler on materials, or a lower hemolysis rate when blood is returned through the check valve.∘ Multiple and / or odd-numbered, evenly spaced openings and locking tabs, which enable low-pressure loss and even flow through the valve arrangement without rotational orientation, even with multiple fluid channels leading from the valve seat and with good centering capability; ∘ Functional use of the demolding flash for valve functions such as friction during axial displacement and tilting insensitive to jamming, eliminating the otherwise usually necessary requirement to produce the injection-molded part with minimal flash; ∘ Large-area activation ring surface made of hard thermoplastic material reduces the activation compression stresses on the machine's activation boss and reduces inaccuracies in the activation path transmission due to elastic compliance on the machine and valve components;∘ Favorable shape in terms of center of gravity and shape asymmetry of the cap and valve for reliable vibration conveyance and position sorting during part preparation and pre-positioning; ∘ Conical, round, centric geometries of the cap and valve allow suction and precise further and final centering with tubular vacuum grippers and round mounting holes; ∘ Option of using a particularly simple, passively acting activation device on the machine side with cost-neutral integration of a progressively acting activation hump spring into the hermetically sealed back of the elastomeric actuator-sensor mat; ∘ Option of using an equally encapsulated, discretely constructed activation device with technical springs in the space behind the actuator-sensor mat;∘ Possibility of using an actively driven activation unit encapsulated behind the actuator-sensor mat with the option of carrying out complete functional tests of the valve arrangement through reversible activation immediately before treatment and, in addition to the check valve function, also being able to use the function of flow paths open on both sides in the process; ∘ Use of the differences between static and sliding friction in the activation mechanism of the cap to achieve a high activation threshold force with a low pushing force after the locking barrier has been overcome; ∘ Use of spherical or pointed knobs or wave structures in the actuator-sensor mat to achieve targeted progressive force-displacement values ​​that can combine a high activation threshold force with a low residual force in the activated position.∘ Valve opening purely by bending processes in the elastomer valve, thus largely eliminating hysteresis and reproducibility fluctuations; ∘ Low tendency to clogging due to the even and complete lifting of the sealing ring when the valve opens, avoiding flow dead zones and fluid dwell times in non-lifting zones of the sealing ring; and ∘ Low sensitivity to causing vibrations and noise, since the valve sealing ring lifts evenly and thus essentially allows only one fundamental vibration mode. In certain embodiments according to the invention, the valve injection mold can also be advantageously constructed according to a favorable open-close concept, whereby the required number of mold cavities is approximately twice as high as for the cap mold due to the longer specific cycle time for crosslinking the liquid silicone. Due to the simple, essentially rotationally symmetrical shape, the flat, sealable mold parting line at the lower peripheral edge of the retaining ring, which is not critical in terms of mold offset and flash, and the very small construction volume of approximately 110 mm^3, it is possible to manufacture the valve extremely cost-effectively. Since LSR components in the Since the check valves are generally most economically removed from the ejector-side mold cavities using laterally applied rotating spatulas, the valve is designed entirely for optimal manufacturability, utilizing the centering cone as the central injection point and, during demolding, as a snubber protruding from the ejector-side mold half. The check valve designs of the functional device according to the invention have the property of being centrally injection-molded and essentially rotationally symmetrical, which is advantageous for a low-warpage mold shape.

[0103] Another advantage is that a large portion of their volume is not located close to the center (mushroom base area), while the portion of their volume near the sealing ring is relatively large and is not located in the immediate vicinity of the flow path end and the venting mold parting line. This means that the liquid injection molding material is not already close to completion of mold filling when filling the sealing ring area, flow rates do not come to a standstill, and air bubbles and weld lines are pushed further. This eliminates the problem of air pockets and weld lines, with the associated geometric inaccuracies on the surface, precisely on the sealing ring, thus reducing the sealing capability of the valve in the annular area of ​​contact with the sealing surface on the valve seat.

[0104] In certain embodiments of the invention, the check valve of the functional device according to the invention has a shape that particularly facilitates filling the injection mold during its manufacture: the centrally injected liquid elastomer initially impacts the stop face and is abruptly deflected into the thin-walled wave shape of the spring diaphragm. After another deflection, it flows through the sealing ring and on to the relatively voluminous retaining ring, where the mold parting line with venting and the end of the flow path are located. Thus, the sealing ring is permeated with well-homogenized injection molding compound at a relatively high flow velocity, thus pushing air pockets and weld lines (partially solidified flow fronts) further. This results in a sealing ring with a particularly precise surface suitable for sealing.

[0105] Due to the low stiffness of elastomer components (here approximately 40 to 70 Shore A) compared to the relatively high stiffness of the cap, in certain embodiments according to the invention, structures for access to sterilization gases, for air removal, and for reducing friction during assembly are advantageously arranged in the cap component rather than in the valve component. Fewer deep structures are required in the cap to achieve equally large open structures in the pressed, assembled state than when corresponding structures are arranged in the valve component. This results from the raised and embossed structures on the elastomer becoming flattened, thereby increasing the undesired direct contact surfaces between the thermoplastic and elastomer components and simultaneously reducing the cross-section of the desired gas-conducting drainage grooves.In addition, the low-defect manufacturing of the surfaces of the elastomer part benefits if there are no fine structures that are difficult to extrude and difficult to vent, which does not need to be taken into account when manufacturing the cap, since small defects in the surface do not affect the function.

[0106] Further potential benefits include, in particular, tolerance optimization. Specifically: 1. Due to the preload of the valve in the cap, the valve adapts to the cap in several axial dimensions and also aligns itself with the stiffer and more precisely manufactured cap in terms of axial runout, radial centering, and axial parallelism, which already reduces or even eliminates some of the valve's dimensional tolerances. 2. Because the "activated" position is only determined by the fact that the cap's lower annular face rests flush against the valve seat ring support, it is irrelevant how far the actuator sensor plate of the treatment machine initiates to displace the cap into the activation protrusion, as long as the travel is at least large enough to ensure that the cap rests flush. This is a significant difference from most of the known, soft-construction valve designs, where the valve's activation travel is proportional to the machine's activation travel.This results in almost complete decoupling between the valve activation paths and the machine activation actuators. 3. Because the cap is orders of magnitude stiffer than the elastomeric valve body, the inherent axial deformations under the applied activation forces are correspondingly lower. As a result, the axial position uncertainty of the cap's centering cone, and thus of the valve's central area, is more than an order of magnitude smaller (0.02 to 0.04 mm) than with the previous capless design, in which the penetration depth and the axial force of the treatment machine's activation protrusion directly influenced the axial displacement of the valve's central area and thus the operating preload of the activated valve.This results in an almost complete decoupling between the preload forces of the valve in the activation position and the activation forces of the machine's activation actuators. 4. The geometric-mechanical chain of influencing tolerances now includes only a small portion of the previous dimensions, namely the dimensions of the valve and the topologies of the valve seat and the cap interior that are directly surrounding it and involved in the valve clamping. Since all of these topologies now have only small dimensions in the range of 0.4 to 3.6 mm in the Z direction, the achievable manufacturing tolerances of the injection molding topologies are correspondingly small, lying in the range of less than + / - 0.03 mm. This results in significant shortening of the tolerance chains and, at the same time, tighter individual tolerances. 5.Due to the flat contact of the two above-mentioned ring surfaces under a residual force of typically 5 to 20 N, the axial runout deviations of both ring surfaces are mutually reduced because they elastically-plastically flatten each other. This is a typical process if injection-molded components, which are fundamentally affected by angular distortion, are subjected to axial compression against counter-surfaces. This results in an increase in accuracy through mutual design optimization of the installed components. 6. The spring diaphragm of the valve has a rolling bellows-like shape. However, the shape changes during the axial deflection of the valve are not the same as with a true rolling bellows, since the cylindrical rolling surfaces to avoid kinetic friction are missing. However, the rolling bellows-like shape has specific advantages over a flat spring diaphragm: 6a.With the same axial preload, the angular compliance at the level of the sealing ring is significantly increased, which leads to more uniform sealing compression and thus a narrower distribution of the opening pressure with radial and angular offset of the valve symmetry axis to the valve seat symmetry axis. 6b. The relative stiffness of the retaining ring in conjunction with the largely vertical wall section between the retaining ring and sealing ring results in a globally specifically stiff sealing ring zone, which is displaced as a whole by the rolling diaphragm and thus adapts to the sealing ring of the valve seat in terms of angular, radial and axial displacement. Locally, i.e. in relation to the local compression of the elastomer valve sealing ring onto the hard valve seat sealing ring, the sealing adaptation of both surfaces is increased by the fact that the valve sealing ring has a relatively sharp edge (pointed element of a sealing press pairing) and is characterized by its low hardness of approx.30 to 70 Shore A locally flattens the valve seat sealing ring. This creates a high local surface pressure, which is the decisive criterion for a locally effective sealing bridging of local irregularities in the two sealing surfaces or foreign bodies present locally in the sealing zone. In most of the valve designs proposed to date, the valve sealing ring zone is thin-walled and globally or overall not very rigid. Irregularities and foreign bodies lead to a global deformation of the sealing ring zone and not to local bridging and encapsulation, which is why the sealing effect is reduced by local gap formation. The valve of the functional device according to the invention therefore seals more reproducibly and better under the influence of local surface defects and foreign bodies present in the sealing ring zone. 6c. The rolling bellows-like shape also influences the linearity of the spring characteristic curve of the axial sealing ring displacement.From a certain minimum axial deflection, rolling bellows exhibit a force that remains constant or even decreases with any further deflection. The minimum deflection is reached when the bending stress state no longer changes with further deflection, i.e. the rolling bellows has assumed a constant, similar shape. The axial deflection required for this is approximately 3 to 5 times the rolling bellows thickness for a real rolling bellows by preloading the cap valve. This travel can be achieved by preloading the cap valve, which is not possible with preload-free designs due to the limited activation travel of 0.8 mm. Of this travel, only approximately 0.4 mm remains for the axial preload after deducting the minimum sterilization gap and cumulative tolerances, which is already less than the existing rolling bellows thickness.The axial force limitation characteristic, typical of rolling bellows, makes it possible to design valves so that the force-displacement characteristic curve runs almost horizontally, thus further reducing the tolerance sensitivity of the opening pressure and flow resistance. 7. By preloading the valve in the cap and removing this preload and further preloading in the second or activated position, the new valve can be preloaded with a significantly greater travel than valves without a cap and without preload. Therefore, to achieve the same preload in the second position, more compliant spring diaphragm geometries with a flatter spring characteristic curve can be used, which lead to flatter pressure loss-volume flow characteristics and thus, with the same activation travel inaccuracy, to smaller uncertainties in the opening pressure, as well as in the pressure losses and pressure loss inaccuracies. 8.However, since the cap design, as explained above, largely decouples the valve from the machine actuators and, in addition, clever component arrangement reduces geometric tolerances, the tolerances of the aforementioned characteristic curve values ​​are further reduced. 9. The low-tolerance second, activated position in conjunction with the flatter valve spring characteristic curve and the stronger preload achieves particularly reliable remanent activation of the valve after dismantling the disposable. The cap, which is held frictionally in the activated position, does not move even if an overpressure of up to 0.6 bar occurs in the disposable, which cannot occur in practice under normal dismantling conditions because the gas compliance of the emptied disposable does not allow such pressure to build up.

[0107] In certain embodiments of the invention, the wedge effect and the higher sealing pressure also result in a higher self-cleaning effect of the valve during opening and closing. This is a particularly useful property because the wedge-shaped arrangement of the valve seat sealing ring causes a normal and a tangential movement to overlap when the valve lifts off. The tangential movement causes the cleaning effect, but also the desired hysteresis effect (higher opening pressure) after a longer sealing time until the valve lifts off. As already indicated above, the preferably conical valve sealing seat has more favorable angular tolerance properties than the flat valve seat, as it is more similar to the shape of a spherical cap.In an ideal design, the valve sealing seat can take the form of a spherical cap, which is stamped with exactly the radius that corresponds to a tolerance-related pendulum misalignment of the valve axis to the valve seat axis: then the valve sealing ring only requires a minimum of global elastic deformation to adapt to the valve sealing seat ring.

[0108] However, the design of the preload conditions is more difficult because the cone walls no longer have a constant gradient.

[0109] Tests with air and various liquids have shown that the valve in certain embodiments according to the invention does not generate any audible noise or measurable pressure oscillations in the intended volume flow range. In X-ray images with continuously flowing air, a uniform opening gap was observed. Related to this is that the valve design in certain embodiments according to the invention has a particularly low tendency to become clogged by adhering particles, particularly with regard to adhering clotting blood, since no sealed sections remain in which the blood flow comes to a standstill. The conical design forms a flow channel which conveys the predetermined geometric course of the inflow from the inside bottom to the top outside in the most continuous way.This also results in a lower flow loss of the housing flow (due to less abrupt flow deflection) and improved ventability of the main flow path (due to higher average flow velocity).

[0110] At very high volume flows outside the specified range, the inner domed ceiling of the cap, in certain embodiments according to the invention, acts as a movement stop for the valve retaining ring lifted by the fluid. The flat movement stop is geometrically designed so that there is no possibility of the valve jamming on the cap dome. At the typical blocking pressures up to approx. 1.5 bar and in the specified volume flow range of 0 to 600 ml / min, the valve opens solely through bending movements, with the inner material area of ​​the valve being guided almost play-free between the centering cone and the stop face and the retaining ring being spaced apart from the cap and valve seat in all spatial directions without contact. By eliminating sliding processes (e.g. in check valves with movable balls), the characteristic curve is highly reproducible and almost hysteresis-free. At normal blocking pressures up to approx.At 2.5 bar, the sealing ring area of ​​the valve presses continuously tighter against the sealing cone of the valve seat, increasing the sealing effect. At extreme blocking pressures up to approximately 5 bar, the spring diaphragm area of ​​the valve bulges downward and returns to its correct starting position when the pressure is released. At normal and extreme blocking pressures, the centering stop dome in the center of the valve seat prevents axial displacement and axial-radial misalignment of the valve position. It also reduces the flow space and thus contributes to a uniform flow velocity.

[0111] During long periods of high flow rates, in certain embodiments of the invention, the valve relaxes by a few millibars toward decreasing flow resistance, a typical behavior of elastomeric materials. Among these materials, silicone rubber occupies a significant position due to its particularly low relaxation rate. However, since the cap also relaxes toward the base of the valve seat due to the residual axial force acting on the cap, a compensating effect occurs, as this relaxation direction coincides with the direction of increasing preload. Thus, the cap-valve design offers particularly low relaxation of the pressure-flow characteristic curve due to its compensating installation arrangement.Through suitable test series, the geometric design, in particular of the conical seat area of ​​the cap, can be optimized so that an optimal average mutual compensation of the relaxations of the valve and cap is determined and implemented, taking into account the component tolerances of the disposable and the machine, the treatment temperatures and times, and the wear processes in the machine.

[0112] The tightness of the dismantled cassette disposable where the check valve is provided has proven to be so reliable that a closure sleeve (with the corresponding sealing function especially on the automatic substituate connector) can be omitted in the series disposable, see here the reference number 41 in Fig. 1 WO 2010 / 121819 A1. This is accompanied by a further simplification of the machine-side actuator-sensor coupling mechanism, which no longer requires a separate stroke for sealing activation of the closure sleeve and thus operates more cost-effectively and reliably.

[0113] The present invention is explained below by way of example with reference to the accompanying drawings, in which identical reference numerals designate identical or similar components. In the partially simplified figures: Fig. 1a bis 1c show the check valve arrangement in a first exemplary embodiment according to the invention; Fig. 1d shows an enlargement of the Fig. 1c ; Fig. 2a bis 2d show the one-piece design of a further embodiment of the invention with a one-piece claw-shaped check valve arrangement; Fig. 3a bis 3c show a valve of another exemplary embodiment with a thermoplastic cap; Fig. 4a bis 4c show a check valve arrangement in a further embodiment of the functional device according to the invention; Fig. 5a bis 5d show a further design of a two-part preloaded check valve with elastomer valve body and thermoplastic locking cap in a further embodiment according to the invention; Fig. 6a bis 6d show a further embodiment of the medical functional device according to the invention, here purely as an example a blood cassette, with a check valve arrangement, in an exploded view; and Fig. 6e bis 6h show the design of the Fig. 6a bis 6d when assembled in different valve positions.

[0114] The Fig. 1a bis 1c show the check valve arrangement 1 in a first exemplary embodiment of the functional device 900 according to the invention.

[0115] Fig. 1a shows the valve arrangement 1 in exploded view, Fig. 1b in the first position, ie in the non-activated open initial position, and Fig. 1c in the second position, i.e. "remanent" (i.e. "permanently" or "remaining") activated check valve position.

[0116] A one-piece valve body 30 is preferably made of silicone rubber. A centrally located cylinder or section of the valve body 30, referred to here as core cylinder 31, serves with its foil-facing end face as a sufficiently rigid transmission element for the pressure transmitted via the cassette foil and the activation actuator of the machine (also referred to as actuator for short, not shown here, but see Fig. 6f ) axial activation stroke to be initiated. A - for example, cup-shaped - radial sealing web 32 is circumferentially (ie in a closed contour or with a closed circumference) fluid-tightly connected to the core cylinder 31. Ribs, here referred to as guide-clamp-drainage ribs 33, which serve for guiding, clamping and draining, are preferably connected in a uniform and odd-numbered division and in a preferably number of more than 2 to an outer region of the core cylinder 31. The guide-clamp-drainage ribs 33 hold the valve body 30 by slight radial clamping and by bridging the radial dimensional tolerances of the valve body 30 and the valve seat 803 of the hard body 830 of the cassette 900 centrically in a sealing cylinder 37 and a guide cylinder 38 (see Fig. 1b ) of the valve seat 803 of the cassette 900.

[0117] The guide clamp drainage ribs 33, for example by means of optional clamp guide knobs 34, which can be axially spaced apart on one and the same guide clamp drainage rib 33, simultaneously prevent tilting of the valve body 30.

[0118] Adjacent guide clamp drainage ribs 33 touch each other in the example of Fig. 1a bis 1d not.

[0119] Due to the knob geometry, i.e. due to the limited axial extension and the crowning, a tolerance-bridging high radial dimension overlap with the adjacent cylinders 37 and 38, which have different diameters, whereby the area of ​​the diameter transition or jump is referred to as the locking step 39, can be achieved with defined frictional centering and axial fixing of the valve body 30.

[0120] The reference numeral 32c denotes a circumferential gap which, with reference to Fig. 1d described.

[0121] Tests have shown that the slip-stick effects are advantageously lower compared to axially continuous ribs, ie ribs without radially projecting clamping guide knobs 34, and thus the possibility of tilting during installation and at the start of the activation stroke is advantageously reduced.

[0122] Fig. 1b shows the first position, the flow-open basic position, in section: The valve body 30 is fixed to the detent step 39 in the flow-open basic position (first position) both by frictional engagement of the clamping guide knobs 34 and by the contact of knobs, referred to here as clamping detent knobs 35, which protrude radially beyond the clamping guide knobs 34. In this position, the radial sealing web 32 is axially disengaged from the sealing cylinder 37, and there is a flow-open annular volume (a sterilization gap). Only by applying a minimum activation force (preferably 20 to 40 N) in the axial direction to the end face of the core cylinder 31 does an axial displacement movement begin, whereby the sum of the static friction forces of the clamping guide knobs 34 and the resulting radial inward deformation force acting on the clamping detent knobs 35 exceed the set limit value.This ensures protection against accidental activation during the production of the 900 cassette.

[0123] Drainage base ribs 36, provided in the base area of ​​the valve body 30—and preferably only at one lower end of its guide-clamping drainage ribs 33—limit the effect of the activation stroke in the axial direction. Furthermore, together with some or all of the other ribs, they can ensure uniform venting and flow around the valve body, as well as safe sterilization using gases.

[0124] Fig. 1c shows the activated check valve position in section: The thin-walled cup shell 32b and the somewhat thicker-walled circumferential radial sealing land 32 with a tapered sealing edge 32a, together with the sealing cylinder 37 of the valve seat 803 of the cassette 900, form a check valve sealing system after the activation stroke has been executed. The circumferential sealing edge 32a of the elastomer valve body 30 rests against the sealing cylinder 37 under radial preload and seals the film-side fluid chamber against the connector-side fluid chamber, i.e., against the chamber 831, from which fluid could flow from the machine-side connector to the valve 30.

[0125] If the connector-side fluid space exceeds a defined opening pressure (of, for example, 180 mbar) against the film-side fluid space, the radially inward-acting fluid force on a cup shell 32b increases, resulting in two elastic deformations, namely a reduction in the diameter of the cup shell 32b and the radial sealing ridge 32 and a radial buckling or folding of the radial sealing ridge 32. In this way, flow lumens open up at one or more locations between the sealing edge 32a and the sealing cylinder 37.

[0126] If a negative pressure that is lower than the set pressure, a constant pressure, or an overpressure against the connector side prevails in the fluid system of the cassette 900 on the foil side (and thus on the side of the channels and chambers), the fluid chamber on the foil side remains sealed against the fluid chamber on the connector side. In the case of overpressure, the pressure applied radially outwardly to the cup shell 32b reinforces the sealing pressure on the sealing edge 32a.

[0127] The Fig. 1a bis 1c thus show a one-piece valve body or insert of the check valve, made of elastomer, of the radial sealing type, in the functional device 900 according to the invention.

[0128] In further exemplary embodiments, the Fig. 1a - 1c The check valve assembly 1 shown may have an additional plug component. Thus, the core cylinder 31 can be provided with a blind hole on the film side or the connector side, which is refilled by a plug made of thermoplastic (the same or similar to the thermoplastic material of the cassette) and provided with drainage ribs. This plug reduces material consumption in the elastomeric valve body and increases the axial rigidity of the core cylinder 31. In this way, the required activation axial stroke can be somewhat reduced.

[0129] Fig. 1d shows an enlargement of the Fig. 1c The calyx mantle 32b can be seen in section.

[0130] The cup shell 32b can be understood as a wall - for example a conical or cylindrical wall - which extends - more or less, or at least in sections - in an open-close direction of the valve body 30.

[0131] The cup shell 32b can be understood as a circumferential wall that surrounds at least a portion of the core cylinder 31 in a closed manner. A circumferential gap 32c can be provided between the wall of the cup shell 32c and the outer, lateral boundary (surface) of the core cylinder 31. The gap can have a gap base 32d, in which the core cylinder 31 or central portions thereof merge into the cup shell 32b.

[0132] The Fig. 2a bis 2d show the one-piece design of a further embodiment according to the invention, with a one-piece claw-shaped check valve arrangement 1 in exploded view (see Fig. 2a ), in a first position ("initial", Fig. 2b ), in perspective views from above and below ( Fig. 2c ), as well as in a second position ("activated", Fig. 2d ).

[0133] A valve body 40 is preferably made of an elastomeric material, preferably silicone rubber. It is preferably designed so that it can be manufactured in a cost-effective on-off injection mold.

[0134] A ring section, referred to here as positioning ring 41, has drainage structures 41a around its perimeter, which ensure accessibility for sterilizing gases when installed. A - with respect to the illustration of the Figur 2a - upper ring end face 41b of the positioning ring 41 points in the direction of the film 800 of the cassette 900. In the first position of the Fig. 2b This surface is essentially completely or at least partially preferably flush with the film 800 or the cassette edge onto which the film 800 is placed or welded, resulting in a simple friction-locked plug-in assembly with an axial movement stop. An outer surface of the positioning ring 41 has a larger diameter than the associated shoulder hole in the cassette 900. The friction-induced holding force in the cassette, which the valve of the Fig. 2a bis 2d in the second position. It is set, for example, to a range of 20 to 30 N.

[0135] The upper annular end face 41b serves to introduce the activation force (greater than, for example, 20 to 30 N) or the activation travel of approximately 1.1 to 1.4 mm during activation in the dialysis machine 1000. The compact design of the geometry of the positioning ring 41 results in an axially rather stiff annular body, which "passes on" the introduced axial travel more precisely during assembly and activation than an elastomeric plunger which is arranged centrally and has a small diameter, such as the inventive embodiment of the Fig. 1 . This means that slightly less gross activation path is required for machine 1000 and film 800.

[0136] A lower annular end face 41c serves as a movement stop and thus the calibration of the opening pressure and the passage characteristic in the second position ("activated").

[0137] A section, referred to here as the passage ring zone 42, consists of individual, loop-shaped, wound webs with gaps arranged between them. The passage ring zone 42 serves to allow fluid to pass through in the "activated" position, holds the valve core in the desired position, and forms an axially resilient support structure that compensates for misalignment.

[0138] The exemplary mushroom-shaped valve core has a stiffer core region 44, which serves as a movement limiter in both axial directions against the film 800 and against a cassette-side plunger 46. These stops are only touched when the specified pressure and flow rate range is exceeded.

[0139] A sealing ring zone 43 of the valve 40, which is designed here as a circumferential lip or circumferential edge, has, in the first position, an annular gap of approximately 0.4 mm, purely by way of example, with a conical sealing seat 45 of the body of the cassette 900, which contributes to ensuring reliable gas sterilization. In the second position, however, the sealing ring zone 43 seals—for example, under a minimum preload of approximately 0.4 mm—against a conical sealing seat 45 of the body of the cassette 900. This type of seal can also be designed as an axial seal with only minor geometric modifications, which is also encompassed by the present invention.

[0140] The Fig. 2a bis 2d thus show a one-piece valve body or insert made of elastomer, which seals conically.

[0141] The Fig. 3a bis 3c show a further exemplary embodiment of a valve with a cap 51, preferably made of thermoplastic (preferably PP). Fig. 3a shows a valve body 50 and the cap 51 of the valve in exploded view (left) and in assembled state (right). Fig. 3b shows the valve in the first position ("initial"), Fig. 3c in the second position ("activated").

[0142] The valve body 50, together with the cap 51, forms the activation and retaining ring of the check valve or check valve assembly. After pre-assembly of the valve body 50, which has a sealing ring 52, in the cap 51, nubs 53 of the valve body 50 protrude radially outward from openings 54 in the cap 51. Both the valve body 50 and the cap 51 optionally have drainage structures 50a and 51a for optimal gas and / or steam sterilizability. They are geometrically matched to one another such that the valve body 50 axially rests with its activation face against the inner activation face of the cap 51 under slight preload.

[0143] The knobs 53 of the cap 51 or the retaining ring together with the ribs 55 of the valve base, in which Fig. 3a The sealing ring 52, for example, continues or adjoins the sealing ring 52, a play-free centering and radially preloaded holder of the valve assembly in the valve seat 803 of the cassette 900, which prevents the valve from independently transitioning from the activated position to the initial position. The aforementioned components can collectively be referred to as the retaining head 57.

[0144] Through the interaction with the step referred to as diameter shoulder 21 in the retaining ring area of ​​the cassette 900 within the cylindrical section of the valve seat 803 of the cassette 900, the required axial displacement force in the valve seat 803 is, for example, approximately 20 N in the removal direction and 30 N in the activation direction. This is sufficient, on the one hand, for sufficiently secure fixation in the gas-open first position during production and, on the other hand, for a low required activation force in the treatment machine.

[0145] Openings 54 and drainage structures 51a also serve - preferably in conjunction with the crowning of the outer activation face 51b of the cap 51 - to provide ventilation and allow the treatment fluids to flow through the valve arrangement 1.

[0146] The cap 51, which is very rigid compared to the valve body 50, or at least stiffer, allows the valve assembly to be installed axially in the first position with an accuracy of approximately + / - 0.2 mm. To overcome the sterilization gap of at least 0.2 mm and to build up sufficient valve preload, a nominal activation travel of approximately 1 mm results. Since only relatively low axial forces are required to move the frictionally held valve assembly, the actuator-sensor assembly of the machine 1000 requires a protrusion of the activation nose of approximately 1.2 to 1.4 mm for reliable activation, i.e., the second position. This is given or achieved when an annular end face 58 of the valve body 50 has approached an annular end face 59 of the valve seat 803 of the cassette 900 until they are in flat contact. Even with a maximum activation force of, for example, 60 N from the machine on the cap 51, the cap only dents axially by about 0.05 mm.

[0147] The Fig. 3a bis 3c The arrows or double arrows indicate the directions in which the valve arrangement can be flowed through: In Fig. 3b Due to the open, first position, these are both flow directions, i.e. from left to right and vice versa. Fig. 3c , which shows the activated, second position in which the valve arrangement acts as a check valve, this is not the case - here, assuming sufficient pressure, the valve arrangement can only be flowed through from left to right.

[0148] The Fig. 3a bis 3c thus show a two-part valve arrangement or a two-part valve insert made of elastomer or thermoplastic, which seals flat, but could also seal conically if adapted accordingly.

[0149] The Fig. 4a bis 4c show a check valve assembly 1 of a further exemplary embodiment of the invention. It is a two-part, conically sealing valve assembly with a valve component made of elastomer (preferably silicone rubber) and a cap component made of thermoplastic (preferably PP), which are inserted into a valve seat 803. The Fig. 4a The valve assembly in an exploded view from below (left) and from above (right), with the components shown above and below and the components shown in the middle shown below and above (relative to the drawing sheet) assembled again. Fig. 4b shows the valve assembly 1 in the so-called "preloaded" (term is explained below) first position ("initial"), and the Fig. 4c shows the valve assembly 1 in the second position ("activated"). The illustrations on the left of the Fig. 4b und 4c show enlarged sections corresponding to the right-hand image.

[0150] The valve body 60 here has, for example, the shape of a cup or bowl with a bellows-like jacket, a largely flat, comparatively rigid valve base 60a and with a tie rod 62 centrally and rigidly connected to the valve base 60a. The valve body 60 is snapped into a matching, central locking opening of the cap 61 by means of the tie rod 62 during pre-assembly.

[0151] Regardless of the Fig. 4a bis 4c In the embodiment of the valve body 60 shown, the latter can have the shape of a vessel which is open at one end thereof, wherein in the interior of the valve body 60 a tie rod extends towards the open end side and possibly protrudes from it.

[0152] The annular end face 60b of the bellows casing facing away from the valve base 60a sits in the cap 61 under slight radial preload of, for example, approximately 0.1 mm and axially under preferably greater preload of, for example, approximately 0.5 mm. The bellows is compressed accordingly, and the axial preload is maintained via the engaged, relatively stiff tie rod 62. The valve is therefore preloaded and radially centered without any play and retains this property even upon later activation of the cap 61 and upon opening of the valve by fluids flowing through it. This axial preload can be referred to herein as the preload of the check valve. This property is only made possible by the use of the cap 61 and brings with it advantages. Without preload, the activation travel would have to be so large that, in the present example, in the first position it would create a sterilization gap of approximately0.2 mm is guaranteed, taking into account all tolerances of the disposable components, including disposable manufacturing. Furthermore, the activation travel would have to be selected to be large enough that, in the first position, taking into account all tolerances of all components, including the machine, there is an axial preload of the sealing ring of the elastomer component against the (here conical) sealing ring of the valve seat, which leads to the desired reliable fluid tightness up to the desired opening pressure. For a desired opening pressure of, for example, 180 mbar, an axial preload force of approx. 1 N is required. If, for example, the safely achievable activation travel of the cap is 0.8 mm (and the associated gross activation travel provided on the machine side is approx.1.4 mm) and the tolerances of the pre-assembled disposable add up to 0.2 mm, this leaves 0.4 mm for the actual axial preload of the valve in the second position. The average spring rate of the axial compliance of the check valve is therefore 2.5 N / mm or 45 mbar / 0.1 mm. With a dimensional uncertainty of 0.2 mm, this leads to an opening pressure uncertainty of 90 mbar, i.e. 50% of the target value. Increasing the fluid flow to, for example, 600 ml / min would result in a pressure loss of 600 mbar.

[0153] By means of the preload described above and a distortion of, for example, 0.4 mm, with the same travel and tolerance conditions as previously mentioned, it is advantageously achieved that the tie rod 62, in the 'activated' position of the valve, just barely lifts axially from an annular surface 61a of the cap 61 assigned to the tie rod 62. The actual axial preload of the valve is now 0.4 mm + 0.4 mm = 0.8 mm. The average spring rate of the check valve 1 must therefore now be only 1.25 N / mm or 22.5 mbar / 0.1 mm so that the desired opening pressure is again 180 mbar, but this time with half the uncertainty of 45 mbar, i.e. only 25% of the target value. Due to the flatter spring characteristic curve, a flatter pressure loss-volume flow characteristic curve is also obtained, so that, for example, at a flow rate of 600 ml / min, a pressure loss of approx. 450 mbar is obtained.This lower pressure loss, in turn, has a positive effect on the accuracy of the characteristic curve and also has other positive properties: The pumps in the cassette 900 and in the machine 1000 can, for example, be designed with a correspondingly lower pressure when using the check valve described here as an inlet check valve for the dialysis fluid. The inlet check valve for venous Luer injection can be designed for a lower opening pressure due to the greater reproducibility of the opening pressure, which means the operator needs less force to inject the medication contents into the bloodstream using a syringe. Since this check valve can also be used for arterial blood return at the end of treatment, the pressure losses also reduce flow velocities and shear rates, thus correspondingly reducing hemolysis.

[0154] The cap 61, optionally made of the relatively stiff material PP (flexural modulus of elasticity approx. 1750 N / mm), in turn has the task of accommodating the preferably elastomeric valve body 60, preferably made of the relatively flexible material silicone rubber (flexural modulus of elasticity approx. 15 N / mm), preloaded without play, holding it in the first position with a small axial tolerance of, for example, + / - 0.1 mm and transferring it with an equally small tolerance into the second position, in which an annular surface 61c of the cap 61 facing away from the film and an annular surface 803a of the valve seat 803 touch each other. In this case, the significantly larger tolerance of the sensor mat 950 supplied by the machine 1000 or directly by means of the actuator 951 (see Fig. 6f ) and the film 800 transmitted activation path and associated activation axial force are kept away from the check valve and decoupled, which cannot be achieved without a rigid cap 61 arranged between the film 800 and the valve body 60. In the embodiment of the cap 61 shown here, it is also easily installed with its annular end face 61b facing the film flush with the film plane of the channel edges of the cassette 900. The cap 61 has radially extending, radially protruding and / or radially resilient tongues 63. They ensure the defined and secure frictional hold of the valve assembly in the first position (the present valve design could optionally be designed as a variant according to the invention such that tongues 63 again protrude radially from the bellows annular end face, which engage through openings in the cap 61 and thus frictionally ensure secure hold in both valve positions).The spring tongue functionality is explained in more detail with reference to the . Fig. 6a bis 6d described. The cap 61 is optionally equipped, preferably on all sides, with numerous drainage and perforation structures, which ensure safe gas sterilization and venting and ensure the low-pressure-loss passage of the treatment fluids in the opening direction (pressure loss without a valve less than approximately 10 mbar at 600 ml / min).

[0155] The Fig. 5a bis 5d show another design of a two-part pre-loaded check valve with an elastomer valve body and a thermoplastic locking cap, which are inserted into a valve seat of the functional device according to the invention. Fig. 5a shows the valve assembly in exploded view (left) and assembled (right). Fig. 5b shows the valve arrangement in pre-tensioned, first position ("initial"), the Fig. 5c shows it in the second position ("activated"), but without flow, and also the Fig. 5d shows it in the second position, but at maximum flow.

[0156] The locking cap 70 largely retains its design known from the previous figures, but now has, in addition, several radially inwardly projecting retaining projections or retaining lugs 71 on the lower annular end 70a. The exemplary locking cap 70 of the Fig. 5a bis 5d is designed so that it can be manufactured extremely cost-effectively in a multi-cavity on-off injection mold with optional central hot runner injections.

[0157] The locking cap 70 has a central actuator engagement surface 72, on which an actuator 951 can act through the film 800 onto the actuator engagement surface 72.

[0158] The valve body 70b has a central conical pin 73, which is received without play in the corresponding cone of the cap 70. A connecting membrane 74 extends between the pin 73 and a retaining sealing ring 75-76-77.

[0159] In the non-installed state, the valve body 70b has a slight downward curvature of a centrally arranged connecting membrane or membrane 78 (relative to the illustration in Fig. 5a ), or facing away from the foil. During the pre-assembly of the valve body 70b in the cap 70 by snapping a support flange 76 of the retaining sealing ring 75-76-77 until it meshes with the retaining lugs 71 of the cap 70 in such a way that the support flange 76 comes to rest on the retaining lugs 71, this curvature is already neutralized or the membrane 78 is elastically deformed in such a way that a slight curvature in the opposite direction, i.e. upwards, see Fig. 5b The curvature in the opposite direction increases during activation, i.e. during the transition to the second position, see Fig. 5c , and once again when flowing through with treatment fluids, see Fig. 5d .

[0160] The retaining sealing ring 75-76-77 is designed to be compact and / or thick-walled relative to the diaphragm 78. The axial displacement of the retaining sealing ring 75-76-77 relative to the mandrel 73 creates, on the one hand, a bending stress in the diaphragm 78, which continually deforms the retaining sealing ring 75-76-77 downwards into its original injection-molded shape. On the other hand, the axial displacement of the retaining sealing ring 75-76-77 also creates a hoop tensile stress in the retaining sealing ring 75-76-77, which tends to return the retaining sealing ring 75-76-77 to its initial diameter. The retaining sealing ring 75-76-77 has the largest diameter in the situation in which the membrane 78 is essentially flatly deformed and therefore exerts a compressive stress radially outward on the retaining sealing ring 75-76-77.As soon as this neutral point is exceeded, this compressive stress decreases again, and the retaining sealing ring 75-76-77 contributes an axial force component that attempts to shift it into the opposite position (in the valve opening direction). This axial force component overlaps with the constantly increasing bending stress in the diaphragm 78 and leads to a reduction in the spring rate of the valve opening behavior. Only through the preload in the detent cap 70 does the actual preload of the valve body 70b in the second position achieve sufficiently high travel, at which this curvature effect can then be exploited to further flatten the characteristic curve.

[0161] The retaining sealing ring 75-76-77 can be a circumferential, radial section which has two different diameters with a step between the two, and which radially closes off the valve body in a section thereof (i.e. is the radial edge).

[0162] The Fig. 5a bis 5c thus show a check valve arrangement in the form of a mandrel plate in a locking cap or a mandrel of the valve body inserted into a cone of the locking cap, which is two-part, made of elastomer / thermoplastic and seals conically.

[0163] The Fig. 6a bis 6d show a further embodiment of the medical functional device according to the invention, here purely as an example a blood cassette 900 with a check valve arrangement 1. They show the components of the check valve arrangement 1 in a perspective exploded view in half section. Kassettenbaugruppe consists of a semi-open treatment cassette 900 or its upwardly open valve seat 803, preferably made of PP or other thermoplastic injection molding materials such as polyvinyl chloride (PVC) or polycarbonate (PC), and a cover film 800, which is applied flush with the channel edge and closes the cassette 900 but is sufficiently stretchable, see Fig. 6a , preferably made of PP-TPE multilayer extrudates (with "TPE" standing for thermoplastic elastomers) or other flexible extrusion materials such as soft PVC or thermoplastic polyurethane (TPU for short).

[0164] The Folie 800 has a thickness of 0.24 mm and is flush with the surrounding Foliensteg 814 welded, glued or pressed on. In its initial state, i.e. in its first position, the film is preferably arranged in a flat manner so that it can be attached to the cassette 900 as best as possible; however, it can also advantageously be pre-bulged upwards (i.e. away from the cassette 900) for a particularly low or non-existent tensile stress on the film 800, so that the displacement or movement required for activation merely causes a buckling. With the flat film arrangement, the small activation stroke of, for example, 0.8 mm results in a film elongation of less than 2%. The inexpensive film type used with a low elastomer content can absorb this elongation without risk of destruction, with the film 800 initially having to withstand a force of approx.absorbs a maximum of 20 N, which must be additionally applied initially, and which is reduced to almost zero during the course of treatment by plastic deformation of the film.

[0165] The Ventilsitz 803 of the Fig. 6d is geometrically designed in such a way that it has no undercuts for demolding as an injection-molded part. Since the check valve function in the treatment cassette 900 always refers to fluids that come from hose lines and are to flow into the cassette 900, the cassette 900 requires a cylindrical Rohranordnung 804, which opens via a hole into the channel and chamber arrangement of the cassette 900 (here, in the lower area of ​​the valve seat 803). Therefore, there are virtually no additional costs for integrating check valve seats of the illustrated design into cassettes 900.

[0166] The valve seat 803 contains at least one outgoing fluid channel 808.

[0167] The valve seat 803 is designed to be particularly rigid in the clamping or activation direction by cylindrical, approximately vertical cylinder walls 836 and by a large-area valve seat support face 837, which can be a circumferential surface and which can be arranged perpendicularly or substantially perpendicularly to the cylinder walls 836 and / or can merge into them.

[0168] The - only preferably cylindrical - Rohranordnung 804 can flow into the cylinder walls 836.

[0169] The outgoing fluid channel 808 preferably branches off above the cylinder walls 836.

[0170] The valve assembly consists of the cap 801 (preferably made of PP or another relatively stiff thermoplastic injection molding material such as PC or rigid PVC), see Fig. 6b , and the valve body 802, see Fig. 6c (preferably made of LSR (Liquid Silicon Rubber), an inexpensive mass elastomer plastic with sufficiently low compression set, good sterilization resistance and good hemocompatibility).

[0171] The Kappe 801 has the shape of a vault with several radially outward and axially upward open Durchbrüchen 805. In these breakthroughs 805 are Rastzungen 806 are arranged, which can be bent radially inward, for example, with a low force of approximately 1 N per 0.2 mm of radial deflection of the tips of the locking tongues 806. The locking tongues 806 only partially close the openings 805, for example, by approximately 30%.

[0172] In the preferred embodiment, the number of apertures 805 and locking tabs 806 is preferably odd, since odd pitches increase the centering accuracy of the cap 801 in the valve seat 803 (in this exemplary embodiment, a locking tab 806 is always opposite two-dimensionally centering apertures 805 or is adjacent to them, while maintaining a gap). The number of apertures or locking tabs is preferably 9 and, with a valve seat outer diameter of 13 mm, can advantageously be in a range of 7 to 11.

[0173] The relatively large number of openings 805 or locking tongues 806 makes it possible to install the valve assembly into the valve seat 803 without a fixed rotational orientation. Even if cylinder walls - preferably vertical or essentially vertical - referred to here as cap receiving valve seat cylinder walls 807 and 817, are interrupted at one to three points by outgoing fluid channels, the remaining wall segments of these cylinder walls or the valve seat 803 are sufficient to center the cap 801 sufficiently precisely, to hold it in the desired positions and to achieve a sufficiently low flow resistance for the treatment fluids through the openings 805.

[0174] At a maximum flow of approximately 600 ml / min, the pure flow resistance of cap 801 in the installed and activated state is, for example, approximately 20 mbar and therefore only represents approximately 4 to 5% of the total flow resistance with the check valve 1 installed.

[0175] The cap 801 is preferably designed so that it can be manufactured particularly cost-effectively in slide-less on-off injection molds with high cavities. It represents the most cost-effective design found to date for the remanently activated check valve of a functional device 900 according to the invention.

[0176] The cap 801 has a circumferential, preferably sharp edge, designated by reference numerals 809 and 827, which are located at the same height as the support arches 810, which are preferably open at the bottom and, for example, U-shaped, which provide stability to the cap 801, and the flexible locking tongues 806, thereby forming the main parting plane of the injection mold. The necessity of burrs and mold misalignment always occurring in the main parting plane of injection-molded components (especially when manufactured using multi-cavity molds) is turned into a virtue here by deliberately incorporating the sharp burr edge and a systematic radial mold misalignment in the form of the edge, which is incorporated into the design, as functional elements for the valve function (explanation below).

[0177] An upper surface or plane, referred to here as the upper cap ring face 811, forms the highest part of the vault construction, which includes the supporting arches 810, and represents the mechanical interface through the foil 800 for introducing the activation force, activation path, and holding force through the actuator-sensor unit (ASE for short) of the machine 1000. It represents a preferably flat ring face interrupted by preferably radially extending structuring grooves 816, the diameter of which can be in a range of 6.5 to 8.5 mm. Thus, the diameter and size of the ring face, as the effective contact surface for an actuator 951 (see Fig. 6f ) during activation, in an area that is favorable for offering the activation hump (not shown) of the actuator-sensor unit sufficient transmission surface for force and displacement, but at the same time is far enough away from the maximum seat diameter of 13 mm, so that on the one hand the stretching of the film 800 during activation (transition to the second position) is limited and on the other hand the activation force to be introduced, which is used solely for stretching the film 800, is minimized and an annular fluid space remains after activation between the film 800 and the vault of the cap 801, which connects the openings 805 to one another and to the incoming and / or outgoing channels with sufficiently low flow resistance.

[0178] A surface or plane closing off the cap 801 at the bottom, referred to here as the lower cap annular face 812, together with a preferably circumferential support surface of the valve seat 803 for the lower cap annular face 812, referred to here as the valve seat stop annular support 813, forms the functional system for ensuring a short activation path and precise, constant position of the cap 801 when the valve is in the second position.

[0179] Both on the upper annular face 811 and in the area of ​​the cone receptacle 815 (which accommodates a centering cone 820 of the valve body in the use state), the cap 801 optionally has numerous structures such as the structuring grooves 816, notches and recesses, which are required so that the sterilization gases can reach a sufficient number of surface areas of the cap 801, the valve body 802 and the cylinder walls 807 and 817 of the valve seat 803.

[0180] To ensure that the component retains a symmetrical and warp-resistant shape, these external and internal structures are arranged concentrically and in equal or even numbers relative to the number of openings 805 / locking tabs 806. Since the latter number is preferably odd, in every half-section illustration (or in every frontal section through the center of the cap 801) one sees a locking tab, a vault, or a support tab 818 or a section thereof on one side (left or right), while this is not the case on the opposite side due to the asymmetry. However, this sectional representation should not lead to the false assumption that structures or supports are missing at any point or that components are hanging in the air without support. Rather, there is always a uniform distribution of material contact and non-contact across the area and circumference.

[0181] The rigidity of cap 801 is contributed not only by the arched structure 810, but also by vertical cylindrical walls 819, preferably provided radially outward, and the preferably steeply conical circumferential walls inside and outside the circumferential gap, referred to here as the cap centering groove 817a. A structure with a relatively uniform wall thickness and high axial rigidity is obtained. An axial force of 60 N on the upper annular end 811 of cap 801, supported by the lower annular end 812 of cap 801, only leads to a lowering of the preferably central conical receptacle 815 by approximately 0.04 mm.

[0182] The diameter of the cylinder wall 807 of the valve seat 803, against which the edge 809 of the cap 801 rests in the second, but not in the first, position, is defined to be larger than the rigid outer diameter of the cap 801 at the edge 827 of the vault 810 and larger than the rigid outer diameter of the cap 801 at the rounded peripheral edge to the lower annular face 812. With this clearance design, the cap 801 can be tilted by up to 6 degrees without jamming at the two hard diameters against the hard cylinder wall 807. However, more than approximately 3.4 degrees of tilting of the cap 801 is not mechanically feasible through tilted activation anyway.

[0183] The valve seat 803 has a detent step 828, which is located at the transition between the cylinder wall 836 and the cap-receiving valve seat cylinder wall 817. It represents a diameter taper toward the interior of the valve seat 803.

[0184] The valve body 802 optionally has a rolling bellows-like shape and in turn optionally comprises the functional elements centering cone 820, which is preferably arranged centrally and rises towards the cap 801 to an end face 829 or ends therewith, stop face 821, against which a centering stop pin 824a of the valve seat 803 strikes in the second position, at least one auxiliary centering protrusion 822, which in at least the second position touches the centering stop pin 824a, and a spring membrane 823, which is provided in the form of a circumferentially closed (i.e., for example, circular) but upwardly (relative to the representation of the figures in the installed state) open channel between the sealing ring 824 and the stop face 821.The valve body 802 further comprises a radially outwardly projecting, preferably circumferential retaining ring 825, which can be overlooked solely by the tip of the centering mandrel, and which is the radially most projecting portion of the valve body 803.

[0185] In a preferred embodiment, the installation opening of the valve seat 803 has a largest diameter of 13 mm (at the location of the foil support).

[0186] The centering cone 820 is, as in Fig. 6c As can be seen, in certain exemplary embodiments according to the present invention, a centrally arranged truncated cone. Its conical surface preferably serves both as an insertion bevel into the associated centering cone area or the cone receptacle 815 during assembly, as well as as a radial centering element for cap 801 with a defined, small residual play.

[0187] In certain exemplary embodiments according to the present invention, the stop face 821 is centrally located and can form the bottom surface of the truncated cone of the centering cone 820. In conjunction with the centering stop pin or dome 824a of the valve seat 803, this results in both an axial, low-play positional restriction of the check valve and a movement stop at extreme operating pressures in the blocking direction of the check valve.

[0188] In certain exemplary embodiments according to the present invention, the optional auxiliary centering protrusions 822, together with the often rounded, substantially cylindrical outer surface of the centering stop pin or dome 824a, advantageously form a further, generally slightly play-prone, radial centering device. The latter can, for example, contribute to (or be responsible for) preventing tilting of the check valve in the valve seat 803 during assembly, while simultaneously exerting as little influence as possible on the opening behavior of the valve during operation.

[0189] The resilient connecting diaphragm or spring diaphragm 823 can advantageously be similar to a rolling bellows. It can be advantageous for holding the sealing ring 824 in the correct position in both operating states or positions: Since it is flexible, axial preloads and axial operating preloads of the sealing ring 824 can be generated against the sealing ring zone 826. The spring diaphragm 823 can form a fluid-tight zone radially up to the sealing ring 824. Finally, the spring diaphragm 823 can also hold the retaining ring 825 under preload on the retaining lugs or support tongues 818 of the cap 801, and it can radially center the retaining ring 825 during assembly and during the operating position in the open flow direction.

[0190] As in the Fig. 6a bis 6d As can be seen, the cap 801 brings the valve body 802 into an elastically prestressed position when the valve body 802 is inserted into the cap 801 at the factory, namely as soon as the valve body 802 is engaged in the cap 801.

[0191] The preload force achieved is preferably dimensioned just below the pressure or force at which the valve is intended to open during normal use.

[0192] Out of Fig. 6c The expert can already predict what the Fig. 6e bis 6h show in detail, namely that the spring membrane 823 can act as a spring or return element when the valve body 802 is made of Fig. 6c into the cap 801 Fig. 6b is engaged. If the valve body 802 is engaged in the cap 801, the valve body 802, which is preloaded by means of the spring diaphragm 823, is supported on the one hand by the retaining ring 825 behind the support tongues 818 and on the other hand by the centering cone 820 in the cone receptacle 815. In this state, the spring diaphragm 823 is elastically preloaded because the valve body 802 is forced into the elastically preloaded state by positive locking due to the selected dimensions of the valve body 802 and cap 801 in the engaged state.

[0193] When the cap 801 together with the valve body 802 locked into it is pushed into the valve seat 803 of Fig. 6d is inserted so that the locking tongues 806 sit in the valve seat wall or the cap-receiving valve seat cylinder wall 817, then a gap of width b exists between the sealing surface or sealing ring zone 826 of the valve seat 803 and the sealing ring 824 of the valve body 802. Between the support tongues 818 and the valve seat stop ring support 813, there is a further gap of width a. If both gaps exist (ie, both are open or detectable), then the first position suitable for gas sterilization of this exemplary embodiment according to the invention exists. The gap b can be smaller or narrower than the gap a.

[0194] By applying a displacement and / or a force greater than the preload force to cap 801, caused by pressing an actuator 951 onto film 800, gap b can be closed when or by sealing ring 824 being pressed sealingly against sealing surface 826. It is assumed that cassette 900 is fixedly mounted with valve seat 803 and cap 801 with valve body 802 is movable / displaceable relative to valve seat 803. If gap b is closed, the second position of the exemplary embodiment is present.

[0195] The cap 801, with the valve body 802 inserted into it, is permeable to liquid due to the openings 805 of the cap 801, so that liquid can penetrate through the cap 801 from the side and / or from above.

[0196] The required displacement / shift to open and close the valve is very small, e.g. only 0.8 mm between closed and open position in the embodiment according to the Fig. 6a bis 6d This enables a very flat spring characteristic curve of the spring diaphragm 823 in conjunction with the preload. The desired sealing force with which the sealing ring 824 is to be pressed sealingly against the sealing surface 826 is thus achieved even with very small displacements and changes only slightly with increasing displacement. As soon as the sealing ring 824 abuts the sealing surface 826 due to a displacement, the sealing force corresponding to the preload is suddenly available between the sealing ring 824 and the sealing surface 826 according to a step function.

[0197] The Fig. 6e bis 6h show the design of the Fig. 6a bis 6d when assembled in different valve positions. Fig. 6e shows it in the first, initial position before closing a machine door, Fig. 6f in the second, activated position with the machine door closed at maximum volume flow of the treatment fluid, Fig. 6g in the second, activated position with the machine door closed at maximum barrier pressure of the treatment fluid, and Fig. 6h in the activated, second position with the machine door open, after the cassette 900 has been dismantled, ie removed from the treatment device.

[0198] In the Fig. 6e bis 6h The large arrows indicate volume flows, the small ones indicate gaps that may arise between the affected components.

[0199] The preload of the valve body 802 is given in the example of Fig. 6a bis 6h by supporting the valve body 802 by means of its retaining ring 825 on the support tongues 818 of the cap 801. In addition, its centering cone 820 rests on the cone receptacle 815. In the Fig. 6h In the position shown, however, the valve body 802 is no longer supported on the support tongues 818. A tensioning of the valve body 802 now occurs with the participation of the sealing ring 824 of the valve body 802, which is supported on the sealing ring zone 826 of the valve seat 803. Bezugszeichenliste

[0200] 1 Check valve arrangement 21 Diameter shoulder 30 Valve body 31 Core cylinder 32 Radial sealing land 32 a Circumferential sealing edge 32 b Cup shell 32 c Circumferential gap 32 d Gap base 33 Guide-clamp-drainage ribs 34 Clamp-guide studs 35 Clamp-lock studs 36 Drainage base ribs 37 Sealing cylinder 38 Guide cylinder 39 Locking step 40 Valve body 41 Positioning ring 41 a Drainage structures 41 b Upper ring face 41 c Lower ring face 42 Passage ring zone 43 Sealing ring zone 44 Core area 45 Conical sealing seat 46 Tappet 50 Valve body 50 a Drainage structures 51 Cap 51 a Drainage structures 51bActivation face 52Sealing ring 53Nubs 54Perforation 55Valve base ribs 57Retaining head 58Annular face 59Annular face 60Valve body 60aValve base 60bAnnular face of the valve body 61Cap 61aAnnular face 61bFoil-facing annular face 61cFoil-facing annular face 62Tie rod 63Tentacles 70Cap,exemplified as a locking cap 70a lower annular face 70b valve body 71 retaining lugs 72 hot runner gating 73 conical mandrel 74 connecting membrane 75-76-77 retaining sealing ring 76 support flange of the retaining sealing ring 75-76-77 78 membrane 800 film 801 cap 802 valve body 803 valve seat 803a annular surface 804 tube arrangement 805 openings 806 locking tabs 807 cap receptacle-valve seat-cylinder wall 808 fluid channel 809 sharp edge 810 static support arches or vault structure 811 upper cap-annular face 812 lower cap-annular face 813Valve seat stop ring support 814Foil web 815Cone holder 816Structuring grooves 817Cap holder valve seat cylinder wall 817aCap centering groove 818Support tongue 819Vertical cylinder walls 820Centering cone 821Stop face 822Auxiliary centering boss 823Spring element,designed as a spring membrane 824 sealing ring 824a centering stop pin or dome 825 retaining ring 826 sealing ring zone 827 sharp edge 828 valve seat locking step 829 end face 830 hard body 831 connector-side space 836 cylinder wall 837 valve seat support face 900 cassette or medical functional device 950 actuator sensor mat 951 actuator 1000 dialysis machine, machine, blood treatment device,

Claims

1. A medical functional device (900) comprising a check valve (1) and a valve seat (803) for the check valve (1), wherein the check valve (1) is designed to assume, in addition to a first position suitable for gas sterilization, in which a sterilization gap remains, a second position in which the check valve (1) performs a non-return function by applying a force to a section of the check valve (1) and / or by shifting it, characterized in that the check valve (1) is designed to remain in the second position after release of the force and / or after the shifting effect following an accomplished transfer into the second position, wherein either - the check valve (1) comprises a valve body (30; 40; 50; 60; 70b; 802) and a cap (51; 61; 70; 801) manufactured separately therefrom, wherein the valve body (30; 40; 50; 60; 70b; 802) latches, jams or wedges with elastic deformation into the cap (51; 61; 70; 801) by applying the force or by means of the shifting actuator; or - a positioning ring (41) of the valve body (30; 40; 50; 60; 70b; 802) comprises drainage structures (41a; 50a; 51a); wherein a sheath surface of the positioning ring (41) comprises a larger diameter than an associated stepped hole in the medical functional device (900); or - a snap-in stage (828) or a step-like diameter taper is designed within a cylindrical section of the valve seat (803) of the cassette (900).

2. The functional device (900) according to claim 1, wherein the check valve (1) is designed to be transferred from the first position into the second position by means of an actuator (951) of a blood treatment apparatus (1000), for the operation of which the functional device (900) is connected to the blood treatment apparatus (1000), wherein the check valve (1) remains in the second position due to friction closure after release of the force or after retraction of the transferring or shifting actuator (951).

3. The functional device (900) according to anyone of the claims 1 to 2, wherein the valve body (30; 40; 50; 60; 70b; 802) comprises a number of knobs which radially protrude outwards from apertures (54; 805) of the cap (51; 61; 70; 801) after connecting the valve body (30; 40; 50; 60; 70b; 802) with the cap (51; 61; 70; 801).

4. The functional device (900) according to claim 1 to 3, wherein the valve seat (803) against which the valve body (30; 40; 50; 60; 70b; 802) and / or the cap (51; 61; 70; 801) seals in the second position, is designed conically, cylindrically or flatly and preferably circumferentially in the sealing area.

5. The functional device (900) according to anyone of the claims 1 to 4, wherein the valve body (30; 40; 50; 60; 70b; 802) is seated radially under a first pre-tension and axially under a second pre-tension in the cap (51; 61; 70; 801), wherein the second pre-tension is larger than the first one.

6. The functional device (900) according to anyone of the claims 1 to 4, wherein the valve body (30; 40; 50; 60; 70b; 802) preferably has the form of a container or a cup and is equipped with a valve tray (60a) comprising a tension rod (62) which is optionally fixed centrally and rigidly to the valve tray (60a), wherein the tension rod (62) is designed for connecting the valve body (30; 40; 50; 60; 70b; 802) with the cap (51; 61) by engaging the tension rod (62) in a snap-in opening of the cap (51; 61; 70; 801).

7. The functional device (900) according to anyone of the claims 1 to 6, wherein the cap (51; 61; 70; 801) has the form of an arch having several apertures (54; 805) opening radially outwards and axially upwards, wherein snap-in tongues (806) are arranged in the apertures (54; 805), preferably even if they are or get bent radially inwards and partially close the apertures (54; 805).

8. The functional device (900) according to anyone of the preceding claims 1 to 7, wherein the cap (51; 61; 70; 801) presents a peripheral edge (809) located at the level of the snap-in tongues (806) and thereby forms the main parting plane of the injection molding tool.

9. The functional device (900) according to anyone of the preceding claims, wherein a circumferential sterilization gap remains in the first position, which is closed in the second position, and wherein the axial mounting position and thus the sterilization gap is maintained by friction closure between components, e.g. on clamping centering ribs.

10. The functional device (900) according to anyone of the preceding claims, designed as blood cassette, cassette, blood tube, infusion tube.

11. The functional device (900) according to claim 1 to 10, preferably designed as a blood cassette (900), which comprises a hard body (830) and a film (800) covering the hard body (830) or parts thereof, wherein the valve seat (803) is provided in the hard body (830), and wherein the check valve (1) is arranged to be transferred into the second position by means of pressure on the film (800) and / or shifting the actuator (951) of the blood treatment apparatus (1000) towards the film (800).

12. The functional device (900) according to claim 11, wherein the film-sided front face (61b) of the check valve (1) does not project beyond the film plane of the blood cassette (900) .

13. The functional device (900) according to anyone of the preceding claims, wherein the check valve (1) or a section thereof is designed to effect a pre-tension of the check valve (1) inserted into the valve seat (803) or of at least a section thereof.

14. The functional device (900) according to claim 13, wherein the pre-tension is effected by means of a spring element (823), which is designed, for example, as a spring membrane.

15. The functional device (900) according to claim 14, wherein the spring element (823) is a section of the valve body (802) .