Testing device and method for leak testing of a medical container, as well as testing system with testing device and medical container

Description

Technical field

[0001] The present disclosure relates to a test device for leak testing of a medical container, a test system comprising the test device and the medical container to be tested, and a method for leak testing of a medical container. Technical background

[0002] Medicinal containers typically contain medicinal substances, particularly powdered and / or liquid chemical substances, such as dry concentrate, which may contain salts and an acid, e.g., acetic acid or citric acid, and potentially other substances, e.g., glucose.

[0003] The applicant's invention is based on containers designed as cartridges or drums, with capacities of several hundred liters, for example. These are primarily used for the storage and transport of dry concentrate, such as for the production of dialysis fluid. Delivering dry concentrate, rather than liquid concentrate, to a medical dialysis facility and preparing / dissolving it there significantly reduces transport weight and costs and considerably improves the energy efficiency of the dialysis process.

[0004] In the dialysis unit, the dry concentrate is dissolved within the cartridge. Since this production step for creating the solution does not take place in a conventional, industrial setting, but rather in the medical facility, and because a leak of the container in the medical facility poses a significant cost and safety risk, it is of utmost importance to ensure the leak-tightness of the containers / cartridges.

[0005] For this purpose, each container undergoes a tightness or leakage test.

[0006] According to standard procedure, the empty containers are filled with water and rinsed. An operator then performs a visual inspection, checking for damp spots or leakage of solution. The quality of such an inspection is individual, meaning it depends heavily on the operator's experience. Filling a container with a capacity of several hundred liters, as well as the subsequent emptying and drying required after testing, each takes several minutes and represents a time-consuming and costly process step. Furthermore, using water as the testing medium has the disadvantage that containers already filled with dry substance or concentrate cannot be tested without dissolving the dry concentrate.If there is uncertainty as to whether the container already filled with dry concentrate is sufficiently leak-proof, it must be emptied again before it can be tested. This is time-consuming and carries the risk of contaminating the dry concentrate already in the container as well as the surrounding area.

[0007] US 2014 0 083 169 A1 describes a portable test device and a method for testing the integrity of flexible containers, particularly aseptic flexible film bags. The containers are inflated with a sterile gas to remove wrinkles and establish a target pressure. The pressure drop is measured over a specified period. If the pressure loss does not exceed a defined threshold, the integrity of the bag is confirmed. The device includes a controller, a pressure transducer, a power source, a blower, and an interface. The method and device avoid helium testing, using air instead and minimizing wrinkling prior to filling.

[0008] US Patent 4,459,843 A describes a device and method for testing containers for pressure loss. The device measures the pressure difference in a container over time and compares it to an acceptable value. A computer automatically adjusts this value. Summary of the present disclosure

[0009] In contrast, the purpose of the present disclosure is to avoid or at least reduce the disadvantages of the prior art and, in particular, to provide a test device for leak testing a medical container, a test system consisting of a test device and a container to be tested, and a method for leak testing the medical container, which represent a lower cost while maintaining the same reliability of the test result.

[0010] The problem is solved, according to the disclosure, by the features of claim 1 with respect to a test device for leak testing a medical container, by the features of claim 12 with respect to the test system, and by the features of claim 13 with respect to the method. Advantageous embodiments are claimed in the dependent claims and are explained in particular below.

[0011] A key concept of the present disclosure is to perform the container tightness test in a dry manner, using a gas, particularly compressed air, as the test fluid instead of a liquid. Dry testing offers the advantages that the container does not need to be dried afterward, and that the test can be performed even with the container filled, since a substance or dry material contained within the container is not dissolved – unlike when water is used as the test fluid. In the case of testing a container filled with an oxidizable dry material, an inert gas can be used as the test fluid.

[0012] The invention relates to a testing device, a testing system, and a method for performing dry testing by means of a pressure test. This involves pressurizing a medical container, in particular a dry concentrate cartridge, with compressed air and measuring the pressure. The time-dependent pressure measurement is compared with a stored, time-dependent pressure characteristic curve. Measured pressure values ​​that lie outside a predetermined tolerance of the pressure characteristic curve indicate leaks or cracks at joints, welds, or in the container body. The test result is reported to a user.

[0013] The container is designed and configured to hold a medical dry substance or medical dry concentrate in solution. The test device is designed and configured for leak testing this medical container, to pressurize the container with fluid, and to record a container response that depends on the pressure and the container's leak tightness. The test device and the container fluidically connected to it constitute the test system. According to the disclosure, the fluid is a gas.

[0014] The recorded container response is a measured pressure over time, and the testing device has a pressure sensing unit that is connected to the container or at least can be connected to it. In contrast to the previously described escaping liquid as the container response, which must be visually detected by a tester, measuring the pressure as the container response is machine-based, precise, and independent of operator experience, thus providing a reliable leak test with minimal effort.

[0015] Furthermore, the test device has a control unit that automates the leak test. This unit contains at least one time-dependent pressure curve for the container, particularly one specific to the container, and a tolerance value for this pressure curve. The control unit is designed to compare the measured pressure over time against the pressure curve and its tolerance. Depending on this comparison, and especially if the tolerance is met or exceeded, a test result of "tight" or "leaking," an error message, or other information is output.

[0016] Preferably, the test device has an operator interface connected to the control unit via a signal, through which this output(s) can be made and through which inputs from the operating personnel can also be made.

[0017] The testing device is particularly preferably designed and configured to test different or specific versions of the container.

[0018] According to a further development of the test device, the pressure characteristic curve and its tolerance are stored in the control unit for different or specific versions of the container.

[0019] The pressure curve and tolerance depend on parameters of the container and, in particular, the test environment. Specifically, the following parameters are relevant: the shape, material, material thickness, volume of the container, whether the container is filled or empty, the type of filling, the degree of filling, the starting pressure from which the pressure is measured over time, and the temperature during testing. Accordingly, the pressure curve and tolerance are specific to these parameters and must be recalculated if the parameters deviate from them.

[0020] According to a further development, the test device is designed, in particular equipped with pneumatic means, to pressurize the container with gas. At least one compressed air coupling for connection to a compressed air source and at least one container coupling for connection to the container are provided. Optionally, an exhaust coupling for connection to an exhaust sink may be provided.

[0021] Preferably, the pressure sensing unit is arranged on or attached to the container coupling, in particular screwed or coupled into it. The advantage of this is that the pressure is measured close to the container and not at a remote point or in a line of the test device. This minimizes damping or delay in the pressure measurement and reduces susceptibility to interference. The result is particularly precise measurement. Furthermore, the pressure sensing unit is connected in a single step along with the connection of the container coupling, eliminating the need for separate couplings and thus minimizing the potential for connection errors.

[0022] The test device proves to be flexible and also safe in testing different containers if, according to a preferred embodiment, it has several differently or specifically designed container couplings for several differently or specifically designed containers. "Different or specifically designed" here means that each specifically designed container coupling is incompatible with each other specifically designed container. In other words, each specifically designed container coupling is only compatible with its assigned, specifically designed container and with no other.

[0023] The testing device is also safer in the testing of, in particular different, containers if, according to a further development, the container coupling has a sensor connected to the control unit via a signal, which is designed to detect whether the container coupling is correctly connected to the container.

[0024] In this case, according to a further development, the respective specifically designed container coupling preferably has a specific RFID read head as a sensor. This is preferably designed and configured to detect and read a specific RFID tag of the specifically designed container and to transmit to the control unit, firstly, the information about which specific container is connected, and secondly, whether the specific container coupling is correctly connected to the container or not.

[0025] The test device is also safer in testing, particularly different types of, containers if, according to a further development, it has a sensor connected to the control unit that is designed to detect whether the container coupling has been removed from a slot of the test device, where it is preferably stored when not in use. Preferably, this sensor is designed simply as a light barrier.

[0026] According to a further development, the test device has a compressed air path via which the compressed air coupling can be connected, in particular connected, to the at least one container coupling and an exhaust air path via which the at least one container coupling can be connected, in particular connected, to the exhaust air sink, in particular to the atmosphere.

[0027] To prevent contamination of the container, or even of the medical dry substance or medical dry concentrate contained therein, the test device, according to a further development, has a first filter unit, in particular a sterile filter, in the compressed air path.

[0028] To prevent the medical dry substance or medical dry concentrate from being carried away to the exhaust air sink, especially into the atmosphere, the test device has a second filter unit in the exhaust air path according to a further development.

[0029] One way to efficiently switch the compressed air path and the exhaust air path is if the test device, according to a further development, has a branch point or a branch at which the exhaust air path branches off from the compressed air path.

[0030] In a preferred embodiment, a check valve is arranged in the compressed air path between the branch and the compressed air coupling, which closes when pressurized with air flowing from the container in the direction towards the compressed air coupling and opens in the opposite direction when pressurized with compressed air.

[0031] To enable individual and reliable control of the compressed air path and the exhaust air path, a separately actuable shut-off valve is arranged in each of the compressed air path and the exhaust air path, according to a further development. The latter is designed, in particular, as an electromagnetically actuated, especially a 2 / 2-way switching valve. Preferably, the respective shut-off valve can be actuated via the control unit.

[0032] According to a further development, the test device has a selection valve, which can be actuated in particular by the control unit, with a supply connection that is connected to the compressed air path and the exhaust air path, in particular to the branch, and with a tank connection for each tank, which is connected to one of the tank couplings. The selection valve has one actuable position for each tank connection. In each position, the supply connection is connected to one of the tank connections but is blocked from the other tank connections. Therefore, with n tank connections, the selection valve has n actuated positions.

[0033] Alternatively, the selection valve can of course be formed in a modular design from a set of individual and individually actuated valves, in particular from a set of 2 / 2-way switching valves, with each tank coupling then being assigned one of the 2 / 2-way switching valves.

[0034] A manually or electromagnetically adjustable pressure regulating valve is preferably arranged in the compressed air path, so that the container or the different or specifically designed containers can be pressurized with a precisely controlled, and in particular specific, compressed air pressure. Preferably, the pressure regulating valve is arranged upstream of the actuated shut-off valve, i.e., in particular between the compressed air coupling and the actuated shut-off valve of the compressed air path.

[0035] In order to protect the compressed air path and the exhaust air path, and in particular the correspondingly connected container via the positions of the selection valve, against overpressure, the test device according to further development has a manually or electromagnetically adjustable pressure relief valve which is in permanent compressed air connection with the supply connection and which is preferably arranged in the exhaust air path.

[0036] In order to protect the test against external influences and also to protect the environment against hazards emanating from the test, the test device, according to a further development, has an enclosure, in particular a mobile one, with a door through which the test device can be fitted with the container(s) to be tested.

[0037] Preferably, the door is monitored for its closed position by a sensor, preferably by means of a light barrier sensor, wherein the sensor is connected to the control unit and the control unit is designed to abort, interrupt and / or issue a warning message if the door is detected as open.

[0038] The door preferably extends partially, and preferably over an upper portion, of the enclosure, so that a view into the enclosure and thus of the container's position in the test device is visible from the underside, making the container particularly visually identifiable. Preferably, the door covers all components of the test device that pose a risk of breakage, especially pneumatic hoses.

[0039] Preferably, the enclosure has a modular design, with the edges of the enclosure formed by a profile frame and the surfaces of the enclosure by panels, resulting in a cost-effective and flexible enclosure construction. Preferably, the enclosure has a cuboid shape.

[0040] To enable easy relocation of the enclosure or test device, basic sections of the enclosure, particularly end sections of the profile frame, are equipped with rollers / transport rollers, according to a further training. Alternatively, the enclosure, and thus the test device, is designed to be stationary.

[0041] According to the present disclosure, a testing system for leak testing of a medical container comprises a testing device designed according to at least one aspect of the preceding description and a medical container to be tested for leaks by the testing device, which is provided and designed in such a way that a medical dry substance or a medical dry concentrate is dissolved in it.

[0042] According to a preferred embodiment of the test system, a coupling of the container is connected to the container coupling of the test device. Preferably, a coupling of the compressed air source is connected to the compressed air coupling of the test device, and the exhaust coupling of the test device is either connected to an exhaust sink, for example a low-pressure vessel, or it is open to the atmosphere.

[0043] According to a preferred embodiment of the test system, the test device has several differently or specifically designed container couplings and several differently or specifically designed containers that can be tested. Each specifically designed container coupling is incompatible with the other specifically designed container. In other words, each specifically designed container coupling is only compatible with its assigned specifically designed container and with no other.

[0044] According to a preferred further development of the test system, the different or specific container couplings each have a sensor connected to the control unit via a signal, which is designed to detect whether the specific container coupling is correctly connected to its assigned, specific container.

[0045] Preferably, the different or specific container couplings each have a specific RFID reading head as a sensor, which is designed and configured to detect and read a specific RFID tag of the coupling of the specifically designed container and to transmit the information to the control unit as to which specific container is connected and whether the specific container coupling is correctly connected to the coupling of the specific container.

[0046] A method for leak testing a medical container is provided with a test device fluidically connected to the container; in other words, with the test system consisting of the test device and the container. Preferably, the test device is configured according to one of the preceding aspects of the description. The container is specifically designed and configured such that, as described above, a medical dry substance or medical dry concentrate, particularly a dialysis fluid, can be dissolved in it. The method comprises the following steps: Applying a fluid to the container using the test device and recording a container response depending on the application and the tightness of the container using a detection unit.

[0047] According to the disclosure, the container is pressurized with a gas (as a fluid), in particular with compressed air. This provides a method for a dry leak test of the container, offering the same advantages as already described in the description of the test device.

[0048] The container response is measured in relation to pressure. Accordingly, the measuring unit is a pressure measuring unit, and the measured container response is a pressure of the container measured over time, in particular a pressure drop of the container measured over time. According to the disclosure, the leak test is carried out by the following steps: The control unit compares the measured pressure over time against a time-dependent pressure characteristic curve of the container and its tolerance stored in a control unit of the test device; and, depending on the comparison, outputs a test result that classifies the container as leak-proof if the tolerance is met, or that classifies the container as leaking if the tolerance is violated, or an error message or information, in each case by means of the control unit, to an operator interface of the test device connected to it via a signal.

[0049] To perform the test, the container is first connected to the test device's container coupling, and the container to be tested is selected on the test device's user interface. Furthermore, it is checked whether the container is correctly connected and whether the selected container and the connected container match. Accordingly, the procedure may include the following steps: Connecting a container coupling of the test device, in particular a specifically designed one, to a coupling of the container, in particular a specifically designed one; selecting a container design by an operator at the operating interface or automatically by means of a sensor-monitored container coupling connected to a control unit of the test device via a signal; and sensor-monitored checking whether the container coupling is correctly connected to the coupling, and / or whether the container coupling is compatible with the coupling.

[0050] If the latter test is positive, a step will be taken Output a confirmation from the control unit to the operator interface; and if not, a step is taken to output an error message from the control unit to the operator interface and / or to interrupt the check via the control unit.

[0051] Furthermore, the procedure may include the following preparatory steps: Connecting the compressed air coupling of the test device to a coupling of a compressed air source; and shutting off or closing all other connections or openings of the container; and optionally connecting an exhaust coupling of the test device to a coupling of an exhaust sink.

[0052] In this state, the container is correctly connected and correctly selected at the user interface. The compressed air source and, if applicable, the exhaust air sink are correctly connected, so the test can therefore be started manually or automatically. In the manual case, the test is started by an operator at the user interface, and the following steps are then preferably carried out: Controlling the exhaust air path and thus disconnecting the container coupling from the exhaust air sink, so that the container can be effectively pressurized with compressed air without creating a bypass to the exhaust air sink. This is preferably achieved by actuating and thus controlling the shut-off valve of the exhaust air path via the control unit; opening the compressed air path and thus connecting the container coupling to the compressed air source. In particular, the shut-off valve of the compressed air path is actuated and opened by the control unit; upon detection of a predetermined, container-specific start pressure, the container coupling is disconnected from the compressed air source by controlling the compressed air path.

[0053] Preferably, the following steps are taken: recording the decrease in pressure over time and during this process the following steps: The process involves comparing the measured pressure over time against the stored, time-dependent pressure characteristic of the container and the tolerance of this pressure characteristic; and, depending on the comparison, in particular on compliance with or violation of the tolerance, the step of outputting a result "tight" or "leaking" and / or an error message for the container.

[0054] Since the container is not rigid but deformable to a certain extent and can absorb a certain amount of deformation work, a further development of the method proves advantageous in which the container is initially subjected to a pressure slightly above a specific starting pressure corresponding to the starting point of the pressure characteristic curve. Accordingly, a predetermined, container-specific overpressure relative to the predetermined, container-specific starting pressure is stored in the control unit. While the container coupling is connected to the compressed air source, the pressure in the container rises and is measured accordingly. According to this further development, the container coupling is only disconnected from the compressed air source once the predetermined, container-specific overpressure is detected. The pressure then decreases and is measured over time.

[0055] Preferably, the pressure then drops slightly below the specific starting pressure. Accordingly, a predetermined, container-specific vacuum relative to the predetermined, container-specific starting pressure is stored in the control unit. Upon detection of this predetermined, container-specific vacuum, the container coupling is reconnected to the compressed air source, so that the pressure subsequently rises again towards the predetermined, container-specific starting pressure.

[0056] Once this is detected, the container coupling is disconnected from the compressed air source, the pressure is measured over time, the pressure is adjusted over time, and the result is subsequently output.

[0057] According to a further development of the procedure, the recording of the predetermined, container-specific pressure characteristic curve and its tolerance can be carried out in the following steps: Recording and storing a specific pressure characteristic curve of a sealed container in the control unit; introducing a defined leak into the previously sealed container; recording the pressure over time of the leaking container and storing it in the control unit; and wet testing of the leaking container and determining whether sufficient tightness is present.

[0058] If sufficient sealing is not achieved, the following steps will be taken: Reducing the leak; and repeating the measurement of the pressure over time of the leaking container and storing it in the control unit; wet testing of the leaking container and determining whether sufficient tightness is present.

[0059] This process is repeated until sufficient tightness is detected during the wet test, meaning the wet test is considered successful. Then the next step is: Storing the last recorded pressure over time as a tolerance of the specific pressure characteristic curve of the sealed container in the control unit.

[0060] As already mentioned, the pressure curve is specific to the design of the container. This means that the pressure curve depends on several parameters of the container. These parameters include: the shape, the material, the material thickness, the volume of the container, whether the container is filled or empty, the type of filling, the degree of filling, the starting pressure, and the operating pressure. Environmental parameters include the temperature during testing, both of the surroundings, the container, and the fluid (i.e., compressed air or water in the case of wet testing). Accordingly, the pressure curve is specific to these parameters and may need to be recalculated if the parameters deviate significantly during testing.

[0061] For a container with a relatively thin-walled construction, the predetermined, container-specific starting pressure is between 0.15 and 0.30 bar, preferably between 0.20 and 0.25 bar, and particularly preferably around 0.23 bar. For a container with a relatively thick-walled construction, the predetermined, container-specific starting pressure is between 0.7 and 0.9 bar, preferably between 0.75 and 0.85 bar, and particularly preferably around 0.8 bar. Brief description of the characters

[0062] The invention is explained in more detail below with reference to preferred embodiments and the accompanying figures. These show: Fig. 1 shows in a perspective view a test device according to a first preferred embodiment of the present disclosure; Fig. 2 shows in a perspective partial view a test device according to a second preferred embodiment of the present disclosure; Fig. 3shows a front view of the test device according to Figure 1 , equipped with a container to be tested; Fig. 4 shows a front view of the test device according to Figure 3 , with the door removed in the illustration; Fig. 5 shows a side view of the test device according to Figure 3 ; Fig. 6 shows a version of the test device for both embodiments according to the Figures 1 to 5 valid pneumatic switching structure; Fig. 7 shows in a front view pneumatic means of the test device according to Figure 1 for supplying the container with compressed air; Fig. 8 shows a flowchart of a leak testing procedure according to a preferred embodiment of the present disclosure; Fig. 9 shows a specific, time-dependent pressure characteristic of a sealed container of the first type, as well as pressure profiles over time of this container with leaks of varying sizes; and Fig. 10shows a specific, time-dependent pressure characteristic of a sealed container of the second type, as well as pressure profiles over time of this container with leaks of different sizes.

[0063] The figures are schematic and are intended only to aid in understanding the invention. Identical elements are identified by the same reference numerals. The features of the different embodiments are interchangeable. Detailed description of preferred embodiments

[0064] Figure 1 Figure 1 shows a perspective view of a test device 1 for leak testing of a medical container designed or intended for dissolving medical dry concentrate (see Figure 1). Figures 3 and 4 ). According to Figure 1The test device 1 is shown without the container. In the illustrated embodiment, it has a cuboid housing, or cuboid enclosure 2, which is designed to hold the container and which accommodates and protects the pneumatic components used for leak testing. The enclosure 2 is constructed as a frame and is composed of frame profiles 4, which form the edges of the cuboid, and plates 6, which form the faces of the cuboid. At their base, i.e., at the bottom end sections of the four vertical frame profiles 4, each profile is fitted with a base roller 8. Thus, the enclosure 2, and therefore the test device 1, is mobile and can be easily moved to another location.

[0065] On the front side, the mobile enclosure 2 has a design according to Figure 1 vertically left-hinged door 10, which is in Figure 1The door 10 is shown closed and allows access to the enclosure 2 for loading the test device 1 with the container to be tested. The door 10 extends according to Figure 1 The enclosure 2 is visible only over the upper half of the front of the test device 1. The lower part of the front of the enclosure 2 has a gap through which the interior of the enclosure can be viewed. This allows for a simple visual inspection, if necessary, to determine whether and, if so, with which container the test device 1 is equipped. The door can be operated by means of a handle 12 located on the right. The door 10 is monitored by a light barrier sensor, and information about its open or closed status is continuously transmitted to an electronic control unit of the test device 1. The test can only be started if the door 10 is detected and reported as closed.

[0066] An electrical control box 14 is provided on the side of the housing. This box contains, among other things, the electronic control unit by means of which the test device 1 and its pneumatic means are controlled for the purpose of leak testing, and which provides a result of the leak test to an operating interface of the test device 1. Below the electrical control box 14, on the outside of the housing 2, two sockets 16, 18 of different or specific configurations are provided, each of which accommodates a specifically designed container coupling (in Fig. 1 not shown, cf. 20, 22 in Figs. 3 to 5 ) is provided for a medical container of specific design.

[0067] Figure 2Figure 1 shows a perspective partial view of a differently designed enclosure 102 of a test device 101 according to a second preferred embodiment of the present disclosure, wherein, unlike the first embodiment, the door 110 is horizontally hinged and has a smaller vertical dimension. The top plate and an upper side plate of the enclosure 102 are removed in the illustration, so that a view into the upper interior of the enclosure 102 is revealed. In contrast to the test device 1 according to Figure 1 The different or specific slots 16 and 18 are provided within the housing 102 with their respective specifically designed container couplings 20 and 22, respectively, and their respective specifically designed container plugs 24 and 26.

[0068] The container plug 24 or 26 is for closing a riser pipe connection of the container during the leak test and the container coupling 20 or 22 is for pressurizing the container with compressed air and measuring the pressure of the container.

[0069] Each container coupling 20 or 22 and each container plug 24 or 26 is adapted in terms of geometry and positive locking to a specific, container-side coupling of the respective container of a specific design. In this way, the container coupling 20 or 22 and the container plug 24 or 26 can only be connected to their assigned, specifically designed container and are otherwise incompatible, thus preventing an accidentally incorrect connection / coupling.

[0070] Figure 3 shows in a front view the test device 1 according to Figure 1 , equipped with a container 28 to be tested, which is arranged on a trolley 30. According to Figure 3 The slots 16 and 18 are provided on the outside of the housing 2, below the control box 14, with the specific container coupling 20 of the first type occupying the upper slot 16 and the specific container coupling 22 of the second type occupying the lower slot 18.

[0071] Figure 4 shows in a front view the test device 1 according to Figure 3 , with door 10 removed in the illustration. Thus, the view into the enclosure 2 with the container 28 arranged therein is completely unobstructed. On the rear, upper wall section of the enclosure 2, a pneumatic control arrangement 32 is arranged on a base plate 34, which is controlled by the Figures 6 and 7 will be explained in more detail.

[0072] Regardless of the specific embodiment, the container coupling 20 or 22 is designed according to the Figures 1 to 6pneumatically connected to the pneumatic control arrangement 32 by means of a pneumatic hose 66 or 68. In addition, a respective pressure sensor 40 and a respective RFID sensor (within the respective container coupling, i.e. concealed) of the container coupling 20 or 22 are connected according to the Figures 1 to 6 The control unit located in the electrical control box 14 is connected to the control unit by means of a signal cable bundle 70 or 72. The respective pressure sensor 40 serves to measure the pressure in the container 28 or 29 under test. The RFID read head detects an RFID tag on the specific coupling of the specific container 28 or 29, to which the specific container coupling 20 or 22 is connected, so that both a correct and a faulty connection of the container coupling 20 or 22 to the coupling of the container 28 or 29 can be signaled to the control unit.

[0073] A light barrier sensor (concealed by the respective container coupling 20 or 22) detects whether the respective slot 16 or 18 is occupied by the associated container coupling 20 or 22, respectively. The light barrier sensors are connected to the control unit in the electrical control box 14 via signal lines 74.

[0074] Figure 5 shows in a side view the unequipped test device 1 according to Figures 3 and 4 With the door closed, 10. The specific slots 16 and 18 are visible in the top view. Slot 18 only has the container coupling 22. This is because, in this case, the container plug 24 is not specific but is used to close both specifically designed containers.

[0075] Figure 6 shows a circuit diagram of the pneumatic control arrangement 32 according to Figure 4 and 7The description of the pneumatic control arrangement 32 is based on Figure 6 schematically, while Figure 7 at the same time illustrates the physical arrangement of the described components on the base plate 34.

[0076] According to the Figure 6 related to Figure 7 The control arrangement 32 has a compressed air coupling 36 for connection to a compressed air source, for example at a pressure level of 8 bar, an exhaust air coupling 38 for connection to an exhaust air sink, and, in the embodiment shown, the two specific container couplings 20, 22. In the illustration according to Figure 6The specific container coupling 20 is connected to the specifically shaped container 28, whose riser pipe connection is closed by the container plug 24. The specifically shaped container 29, on the other hand, is not connected, but is shown with dashed lines for illustrative purposes. Each of the specific container couplings 20, 22 is assigned a pressure sensing unit 40. A compressed air path 42 extends from the compressed air coupling 36 to a supply port 44 of an electromagnetically actuated 3 / 2-way switching valve 46. Starting from the compressed air coupling 36, the compressed air path 42 contains an adjustable pressure regulating valve 48, a sterile filter 50, an electromagnetically actuated 2 / 2-way switching valve 52 (shut-off valve), a check valve 54 closing towards the compressed air coupling 36, and a branch 56 of an exhaust air path 58. The compressed air path ends at supply port 44.An adjustable pressure relief valve 60 is permanently connected to the exhaust air path 58, protecting the compressed air path, the containers 28 and 29, and the exhaust air path against overpressure. Furthermore, an electromagnetically actuated 2 / 2-way switching valve 62 (shut-off valve) is located in the exhaust air path 58, and downstream of this, an exhaust air filter 64 is arranged, which prevents the discharge of dry matter into the atmosphere. The exhaust air path terminates at the exhaust air coupling 38. The selection valve 46 has two container connections, each connected to one of the specific container couplings 20 and 22, and two switching positions. In each switching position, one of the container connections is connected to the supply connection 44, while the other container connection is shut off from the supply connection 44.

[0077] Figure 8shows a flowchart of a method for leak testing according to a preferred embodiment of the present disclosure.

[0078] As a preliminary step, the test device 1 is connected to a supply voltage of 230VAC and the compressed air coupling 36 is connected according to Figure 6 The device is connected to a compressed air source, preferably at 8 bar. Optionally, the test device 1 can be connected to a local network, for example via Ethernet, to read data logs from the control unit. Command input by an operator is via a user interface, in particular a PLC with a touchscreen. As a preliminary step, the sensor-monitored door 10; 110 is also checked according to the Figure 1 , 3 ; 2The container is inserted into the test device 1. Depending on the configuration of container 28 or 29, the corresponding sensor-monitored container coupling 20 or 22, located at slot 16 or 18, is available. The specific container 28 or 29 is connected to the specific container coupling 20 or 22, and the door 10 or 110 is closed.

[0079] According to one embodiment of the method, the test device 1 checks whether the connected container 28 or 29 corresponds to the selected container and whether the door 10 or 110 is securely closed. The inlet pressure is set to a defined maximum pressure via the pressure regulating valve 48. At the start of the test, the 2 / 2-way valve 52 opens the compressed air path 42, and the 3 / 2-way valve 46 connects the specific container coupling 20 or 22 to the compressed air path 42. Simultaneously, the 2 / 2-way valve 62 closes the exhaust air path, so that the air is directed into the container 28 or 29. The pressure is measured by the pressure sensing unit 40, which is located in the container coupling 20 or 22 of the container 28 or 29, and compared by the control unit (PLC) with the specific pressure characteristic and its tolerance. Finally, depending on the comparison, an evaluation of the tested container 28 or 29 is issued.The compressed air path 42 is shut off and the exhaust air path is opened via the de-energized shut-off valves 52 and 62, thus depressurizing the container 28 or 29. The container 28 or 29 is disconnected and removed from the test device 1, and the test device 1 is then released.

[0080] Step S1 then starts the test and selects the specific container 28 or 29. The operator also accesses configuration menus K1 and K2 of the user interface. Here, configurations relating to the selected container 28 or 29, the test device 1, and the test procedure can be viewed, selected, or changed. These include the actuation of the shut-off valve 52 in the compressed air path 42 for filling (normally closed), the actuation of the shut-off valve 62 in the exhaust air path 58 for emptying (normally open), the actuation to switch the selection valve 46, a filling duration in seconds, a test duration in seconds, the measured pressure in real time, a target pressure, the tolerance in %, the overpressure, status displays for the respective sensor-monitored container coupling, etc.

[0081] The process continues at the user interface by pressing the button. OK.

[0082] After these test preparations, the leak test can now be started. This can be done by removing the specific container coupling 20 or 22 from slot 16 or 18, which is monitored by a light barrier sensor. The signal from the respective light barrier automatically selects the specific container for testing. If this does not happen, it can be selected manually via the user interface.

[0083] A query S3 then checks whether the container 28 or 29 to be tested is correctly connected. If the query is confirmed with OK, the container 28 or 29 is connected to the compressed air source and filled to an overpressure above a specific starting pressure, in particular one corresponding to the specific design of the container. For example, the overpressure values ​​are 0.05 bar above the starting pressure, 0.25 bar above the starting pressure for container 28 (first design), and 0.85 bar above the starting pressure for container 29 (second design), to allow the respective plastic container to expand according to its design.

[0084] In step S4, the system then waits until the measured pressure has dropped to a value slightly below the start pressure (negative pressure, below the start pressure). This so-called negative pressure is, for example, 0.002 bar below the start pressure, such as 0.198 bar to 0.2 bar for container type 28 and 0.798 bar to 0.8 bar for container type 29.

[0085] Upon detection of this negative pressure, in step S5 the container 28 or 29 is reconnected to the compressed air source until the test-specific starting pressure (0.2 or 0.8) is detected. Once this pressure is detected, the container 28 or 29 is disconnected from the compressed air source, and the pressure is measured over time.

[0086] In step S6, the measured pressure over the time of container 28 or 29 is compared against the stored, specific pressure characteristic and the tolerance of this pressure characteristic. The test time is, for example, 60 seconds.

[0087] If the control unit determines that the tolerance is met within the test time, the positive result is output to the operator interface. Otherwise, a query S7 is sent asking whether the test should be repeated or aborted. If abort is selected, the shut-off valve 62 in the exhaust path 58 is de-energized, thus connecting the container 28 or 29 to the exhaust sink, allowing the compressed air to flow out of the container 28 or 29.

[0088] According to step S8, if the exam is failed, it is asked whether the exam should be repeated or whether it should be cancelled completely.

[0089] The process can be cancelled at any time by pressing a cancel button. X The user interface will be aborted, thus aborting the leak test (End).

[0090] Figure 9Figure 1 shows a specific, time-dependent pressure characteristic curve "+" of the first-order leak-tight container 28, as well as its tolerance "x" or tolerance curve, which a container 28 under test must not fall below during the leak test in order to be considered sufficiently leak-tight. The determination of the pressure characteristic curve "+" and its tolerance "x" is based on the following procedure. First, the first-order leak-tight container 28 is pressurized with compressed air up to a starting pressure of 0.2 bar. With the compressed air path 42 and exhaust path 58 closed, the pressure is recorded over time, and the specific pressure characteristic curve "+" is obtained. This curve shows a very small pressure drop over time, which represents the high leak tightness of the container. Subsequently, a 1 mm diameter hole is drilled into a weld seam on the top of the container 28, and the leak test with pressure measurement over time is repeated.Now, according to... Figure 9The curve below shows the steepest pressure drop. To further reduce this induced leak, metal pins of increasing diameter were sequentially inserted into the bore, and the pressure was measured over time after each insertion. Larger diameter metal pins resulted in a progressive reduction of the leak, so the subsequent curves show an increasingly smaller pressure drop. Next, a 0.9 mm diameter metal pin was inserted into the bore, and the resulting pressure reading over time was indistinguishable from that of a sealed container. The container was then subjected to a wet test with dissolved dry concentrate, and the leak showed no escaping. To increase the size of the leak again, a 0.8 mm metal pin was inserted into the bore.The pressure recorded over time "x" during the subsequent test shows just a deviation from the specific pressure characteristic "+" of the sealed container 28. This leak size thus represents the limit of a leak that can just be detected, and the associated, recorded pressure over time "x" represents the tolerance to the specific pressure characteristic "+" that a test specimen of the specific container 28 must not fall below in order to be classified as "sealed".

[0091] Figure 10 Figure 1 shows a specific, time-dependent pressure characteristic curve "+" of a leak-tight container of the second type 29, as well as its tolerance "x" or tolerance curve, which a test specimen of the specific container 29 must not fall below during the leak test in order to be considered sufficiently leak-tight. The determination of the specific pressure characteristic curve "+", as well as its tolerance "x", was carried out analogously to the procedure that was carried out with reference to the container of the first type 28 based on the Figure 9 as described. Due to the greater wall thickness of the second type of container 29, the leak test is carried out with an increased specific starting pressure of 0.8 bar. Although the tolerance "x" according to Figure 10 compared to that according to Figure 9 a significantly more pronounced pressure drop, however, no leakage could be detected during the subsequent wet test, so the pressure over time is defined as the tolerance of the pressure characteristic curve "+" of the container of the second type 29 according to the curve "x". Reference symbol list

[0092] 1; 101 Test device 2; 102 Enclosure 4 Profile 6 Plate 8 Roller 10; 110 Door 12 Handle 14 Control box 16, 18 Coupling slot 20 Container coupling, first type 22 Container coupling, second type 24 Container plug, first type 26 Container plug, second type 28 Container, first type 29 Container, second type 30 Trolley 32 Pneumatic control assembly 34 Base plate 36 Compressed air coupling 38 Exhaust coupling 40 Pressure sensing unit 42 Compressed air path 44 Supply connection 46 3 / 2-way selector valve 48 Pressure regulating valve 50 Sterile filter 52 Shut-off valve 54 Check valve 56 Branch 58 Exhaust path 60 Pressure relief valve 62 Shut-off valve 64 Exhaust filter 66, 68 Pneumatic hose 70, 72 Signal cable bundle pressure sensor / RFID sensor S1 Start leak test of a container S2 Select a specific container S3 Pressure above start pressure S4 Wait until pressure below start pressure S5 Pressure at start pressure and pressure recording over time S6 Comparison of pressure over time against pressure curve and tolerance S7 Output result S7 Query for retesting K1, K2 configuration container, test device, test procedure +Pressure characteristic xTolerance (curve)

Claims

1. A testing device for testing the leak-tightness of a medical container (28, 29), which is provided and configured to bring a medical dry substance or a medical dry concentrate into solution therein, wherein the testing device (1; 101) is provided and configured to apply a gas to the container (28, 29) and to detect a container response dependent on the application and a leak-tightness of the container (28, 29), wherein the container response is a pressure over time, and wherein the testing device (1; 101) has a pressure detection unit (40) for detecting the container response, which is provided and configured for connection to the container (28, 29), characterized by a control unit, in which a time-dependent pressure characteristic curve (+) of the container (28, 29) and a tolerance (x) with respect to this pressure characteristic curve (+) are stored, and which is configured to compare the detected pressure over time against the time-dependent pressure characteristic curve (+) for compliance with the tolerance (x) and, depending on the comparison, to output a test result "tight" or "leaky" or an error message or information.

2. The testing device according to claim 1, characterized in that the pressure characteristic curve (+) and tolerance (x) are each stored in the control unit for specific embodiments of the container (28, 29).

3. The testing device according to one of the preceding claims, characterized in that a compressed air coupling (36) for connection to a compressed air source, at least one container coupling (20, 22) for connection to the container (28, 29) and optionally an exhaust air coupling (38) for connection to an exhaust air sink are provided for applying gas to the container (28, 29).

4. The testing device at least according to claim 3, characterized in that the container couplings (20, 22), in particular for different or specific embodiments of the container (28, 29), are designed differently or specifically, so that they are incompatible with the respective other specific design of the container (29, 28), in particular they cannot be coupled thereto.

5. The testing device according to claim 1 as well as according to claim 3 or 4, characterized in that the container coupling (20, 22) has a sensor which is signal-connected to the control unit and which is configured to detect whether the container coupling (20, 22) is correctly connected to the container, and / or that the testing device (1; 101) has a sensor which is signal-connected to the control unit and which is configured to detect whether or not the container coupling (20, 22) is removed from a slot (16, 18) of the testing device (1; 101), at which it is preferably kept ready when not in use.

6. The testing device at least according to claim 3, characterized by a compressed air path (42), via which the compressed air coupling (36) can be connected to the at least one container coupling (20, 22), and an exhaust air path (58), via which the at least one container coupling (20, 22) can be connected to the exhaust air sink, in particular to the atmosphere.

7. The testing device according to claim 6, characterized in that a first filter unit (50) for preventing contamination of the container (28, 29) is arranged in the compressed air path (42), and / or that a second filter unit (64) for preventing contamination of the exhaust air sink, in particular of the atmosphere, is arranged in the exhaust air path (58).

8. The testing device according to claim 6 or 7, characterized by a branch (56), at which the exhaust air path (58) is branched off from the compressed air path (42), wherein a non-return valve (54) is arranged in the compressed air path (42) between the branch (56) and the compressed air coupling (36), which closes in the direction towards the compressed air coupling (36) and opens in the opposite direction.

9. The testing device according to one of claims 6 to 8, characterized in that an actuatable shut-off valve (52, 62) is arranged in the compressed air path (42) and in the exhaust air path (58) and via which the compressed air path (42) and the exhaust air path (58) can be opened and closed independently of each other, in particular via the control unit.

10. The testing device according to one of claims 6 to 9, characterized by a selection valve (46) with a supply connection (44), which is connected to the compressed air path (42) and to the exhaust air path (58), in particular to the branch (56), and with in each case one container connection per container coupling (20, 22), and with in each case one position per container connection, wherein in the respective position, the supply connection (44) is connected to the container connection and is blocked against the other container connections.

11. The testing device according to one of the preceding claims, characterized by an, in particular mobile, housing (2; 102) with an, in particular sensor-monitored, door (10; 110), through which the testing device (1; 101) can be equipped with the container or containers (28, 29) to be tested.

12. A testing system for leak testing a medical container, with a testing device (1; 101), which is configured according to one of the preceding claims, and with the medical container (28, 29), which is provided and configured to bring a medical dry substance or a medical dry concentrate into solution therein.

13. A method for leak testing a medical container (28, 29) with a testing device (1; 101), which is fluidically connected to the container (28, 29) and which is configured in particular according to one of the preceding claims, wherein the container (28, 29) is configured such that a medical dry substance or a medical dry concentrate is brought into solution therein, with steps - applying a gas, in particular compressed air, to the container (28, 29) via the testing device (1); and - detecting a container response depending on a leak-tightness of the container via a detection unit (40), wherein the detection unit is a pressure detection unit (40) and the detected container response is a detected pressure of the container (28, 29) over time, in particular a pressure drop of the container (28, 29) over time, characterized by a step - comparing the detected pressure over time against a time-dependent pressure characteristic curve (+) of the container (28, 29) and the tolerance (x) thereof stored in a control unit of the testing device (1; 101), via the control unit; and, depending on the comparison, - outputting a test result "tight" when the tolerance (x) is complied with or "leaky" when the tolerance (x) is violated or an error message or information, via the control unit to an operating interface of the testing device (1; 101), which is signal-connected thereto.

14. The method according to claim 13 with the testing device (1; 101) according to claim 5, in particular according to claims 4 and 5, characterized by preparatory steps - connecting a container coupling (20, 22), in particular specifically designed, of the testing device (1; 101) to a coupling of the container (28, 29), in particular specifically designed; - selecting a design of the container (28, 29) by an operator at an operating interface or automatically via a sensor-monitored container coupling (20, 22), which is signal-connected to a control unit of the testing device; and - sensor-monitored or visual testing, whether the container coupling (20, 22) is correctly connected to the coupling, and / or whether the container coupling (20, 22) is compatible with the coupling; and if so - outputting a confirmation via the control unit to the operating interface; and if not - outputting an error message via the control unit to the operating interface and / or interrupting the test via the control unit.

15. The method according to claim 13 or 14, characterized by preparatory steps: - connecting a compressed air coupling (36) of the testing device (1; 101) to a coupling of a compressed air source; and - blocking or closing all other connections or openings of the container (28, 29); and optionally - connecting an exhaust air coupling (38) of the testing device (1; 101) to a coupling of an exhaust air sink.

16. The method according to claim 15, characterized by steps: - starting the test via an operating interface; - connecting the container coupling (20, 22) to the compressed air source by opening a compressed air path (42); - disconnecting the container coupling (20, 22) from the compressed air source by closing the compressed air path (42) while detecting a predetermined, container-specific starting pressure; as a result - comparing the detected pressure over time against a stored, time-dependent pressure characteristic curve (+) of the container (28, 29) and a tolerance (x) of this pressure characteristic curve (+); and, depending on the comparison, in particular depending on compliance with or violation of the tolerance (x); - outputting a result "tight" or "leaky" and / or an error message for the container (28, 29).

17. The method according to claim 16 with a predetermined, container-specific overpressure relative to the predetermined, container-specific starting pressure, characterized in that the container coupling (20, 22) is disconnected from the compressed air source while detecting the predetermined, container-specific overpressure.

18. The method according to claim 17 with a predetermined, container-specific underpressure relative to the predetermined, container-specific starting pressure, characterized in that the container coupling (20, 22) is again connected to the compressed air source while detecting the predetermined, container-specific underpressure, and that as a result, the container coupling is again disconnected from the compressed air source while detecting the predetermined, container-specific starting pressure.