ADAPTER FOR CONNECTING A MEDICAL HOLLOW BOX TO A TENSILE / PRESSURE MEASURING DEVICE, TESTING ARRANGEMENT, METHOD FOR TESTING THE SEALANCE OF A MEDICAL HOLLOW BOX, AND USE OF A TENSILE / PRESSURE MEASURING DEVICE

Description

[0001] The invention relates to an adapter part for connecting a medical hollow body to a tension / compression measuring device, a test arrangement with a tension / compression measuring device and such an adapter part, a method for testing a tightness of a medical hollow body using such an adapter part, and a use of a tension / compression measuring device for testing a tightness of a medical hollow body.

[0002] It is necessary to test the tightness of medical hollow devices, particularly those intended for later distribution pre-filled with a pharmaceutical product, such as syringes and cartridges, but also connectors, adapters, or the like. Standardized leak tests exist for this purpose, which specifically stipulate that a certain positive or negative pressure must be maintained inside such a medical hollow device for a predetermined period of time without leakage. Of course, it is possible to provide dedicated, specifically equipped facilities to conduct such leak tests; however, this is complex and expensive. It is also possible to conduct such leak tests virtually manually with a low degree of automation; however, this is time-consuming and labor-intensive, as well as inaccurate.There is therefore a need, on the one hand, to be able to conduct such leak tests using equipment / devices that also allow for other uses, if possible already used in the development and / or testing of medical hollow bodies, and, on the other hand, to achieve the highest possible degree of automation of such leak tests. Various examples of means for testing the leak tightness of hollow bodies are described in the prior art documents CN109297656A, GB2078380A, CN108303224A, CN106813879A, and US3132508A.

[0003] The invention is based on the object of providing a test arrangement with a tension / compression measuring device and an adapter part, a method for testing the tightness of a medical hollow body using such a test arrangement for testing the tightness of a medical hollow body, wherein the aforementioned disadvantages do not occur, and wherein preferably at least one of the aforementioned advantages is at least partially realized. This object is achieved by providing the present technical teaching, in particular the teaching of the independent claims and the embodiments disclosed in the subclaims and the description.

[0004] The object is achieved with a test arrangement according to claim 1. This test arrangement contains an adapter part which is configured to connect a medical hollow body to a tension / pressure measuring device, wherein the adapter part has a first connection end which is configured to connect the adapter part in a fluid-tight manner to an interior of a medical hollow body. The adapter part also has a second connection end, wherein the second connection end has a pressure chamber and is configured to bring the adapter part into operative connection with a tension / pressure measuring device such that a pressure in the pressure chamber can be adjusted by means of the tension / pressure measuring device. The adapter part also has a hollow channel which passes through it from the pressure chamber to the first connection end.In particular, the hollow channel is open at the first connection end, i.e. the hollow channel opens at the first connection end to an external environment of the adapter part, or the hollow channel opens into the first connection end. In particular, the adapter part is open at the first connection end, wherein the hollow channel is accessible from the first connection end. By means of the tension / pressure measuring device, the pressure in the pressure chamber can be adjusted, wherein the hollow channel is fluidically connected to the pressure chamber and at the same time can open at the first connection end into the interior of a hollow body connected to the adapter part in a fluid-tight manner, it is ultimately possible to adjust the pressure inside the medical hollow body by means of the tension / pressure measuring device, in particular by controlling the tension / pressure measuring device.It is then possible to record, in particular measure, the pressure in the hollow channel, the pressure chamber, and / or in the interior of the medical hollow body. The adapter part thus opens up the possibility of using a tension / compression measuring device to carry out leak tests on medical hollow bodies. Such tension / compression measuring devices are typically already available in the field of development / testing of medical hollow bodies and are used there in particular to test, for example, the displacement forces of plugs that are arranged so that they can be moved inside such a medical hollow body. This means that a device can be used to carry out the leak tests which, on the one hand, can also be used for other purposes and, on the other hand, is typically already available.Furthermore, it is possible to operate such a tension / compression measuring device at least largely automatically, so that ultimately a leak test carried out using such a tension / compression measuring device can also be at least largely automated.

[0005] A medical hollow body is understood here in particular to mean a hollow body which is selected from a group consisting of a vessel for pharmaceutical substances, in particular for medical active ingredients and / or excipients; a syringe; a carpule; a connector, in particular a needle-free connector, in particular a Luer connector, in particular with a Luer connector or with a plurality of Luer connectors, in particular a connector with a small diameter according to the ISO 80369 family of standards, in particular DIN EN ISO 80369-7, in the version applicable on the date determining the priority of the present protective right, in particular DIN EN ISO 80369-7:2017-10; and an adapter, in particular a Luer adapter, in particular with a Luer connector or with a plurality of Luer connectors, in particular an infusion adapter.In particular, a medical hollow body is a part or vessel having a hollow space that can be closed at two ends by closures and / or plugs and is preferably closed as intended. In particular, such a medical hollow body is a syringe or a cartridge.

[0006] In particular, a leak test is carried out on such a medical hollow body by closing a first, preferably distal end of the medical hollow body with a closure or plug, wherein a certain pressure in the interior of the hollow body is set and recorded over a certain time via a second, preferably proximal, still open end.

[0007] A pressure measuring device can also be connected to the first, preferably distal end of the medical hollow body in order to detect, in particular measure, the pressure in the interior of the medical hollow body - and thus at the same time the pressure in the hollow channel.

[0008] A distal end is understood here, in particular, to be an end of the medical hollow body that, when used, is intended to face a patient and / or an injection site and preferably faces away from a user of the medical hollow body. The other end of the medical hollow body is referred to as the proximal end.

[0009] A tensile / compression measuring device is understood, in particular, to be a device configured to apply tensile or compressive forces to test specimens, in particular—preferably additionally—to measure tensile or compressive forces on test specimens. Such a tensile / compression measuring device comprises, in particular, a base body and an active end that can be displaced in the axial direction relative to the base body. The active end is preferably designed as a measuring carriage that can be displaced on a measuring tower. By displacing the active end relative to a test specimen, tensile or compressive forces can be introduced into the test specimen.

[0010] In particular, a tensile / compression measuring device is preferably understood to mean a device which is designed to apply tensile and compressive forces to test specimens, in particular - preferably additionally - to measure tensile and compressive forces on test specimens.

[0011] In particular, the tensile / compression measuring device is preferably configured to apply mechanical tensile and / or compressive forces to test specimens, and preferably to measure mechanical tensile and / or compressive forces on test specimens.

[0012] A fluid-tight connection between the adapter part and the interior of the medical hollow body is understood in particular to mean that the adapter part is connected to the medical hollow body via the first connection end in such a way that pressure adjustment in the interior of the medical hollow body is possible via the adapter part without leakage in the region of the connection between the first active end and the medical hollow body. It is sufficient if the connection between the adapter part and the medical hollow body is designed in such a way that, at pressures such as those required or prescribed for the intended leak tests, no leakage occurs, or at least no leakage that impairs the leakage test. It is possible, but not absolutely necessary, for the connection to be designed to be fluid-tight beyond this, i.e. leak-free even at higher pressure differences.

[0013] The first connection end preferably has a sealing device for fluid-tight connection to the medical hollow body. In a preferred embodiment, the sealing device has at least one sealing element, in particular at least one sealing ring, particularly preferably two sealing elements, in particular two sealing rings—preferably arranged at a distance from one another. The sealing device is preferably arranged on an outer peripheral wall of the first connection end and, in the assembled state, cooperates sealingly with an inner wall of the hollow body.

[0014] A positive connection of the first connection end with the medical hollow body is also possible, for example via a Luer cone with thread.

[0015] Using the tension / pressure measuring device, a pressure in the pressure chamber can be adjusted, in particular when the first connection end is fluid-tightly connected to the medical hollow body and, at the same time, the second connection end is operatively connected to the tension / pressure measuring device. A suitable fluid is preferably used to build up the pressure, in particular a gas or liquid, for example, air, nitrogen, carbon dioxide, a noble gas, water, a pharmaceutical oil or grease, or the like.

[0016] Using the tension / compression measuring device, an overpressure, for example of approximately 300 kPa, or a negative pressure, for example of 40 kPa, can be set in the pressure chamber relative to an ambient pressure, in particular normal pressure, in particular 1013 mbar. This allows both leak tests requiring the setting of an overpressure and leak tests requiring the setting of a negative pressure to be performed.

[0017] According to a further development of the invention, the adapter part has a pressure measuring channel which branches off from the hollow channel or the pressure chamber between the first connecting end and the second connecting end. The pressure measuring channel is thus in fluid communication with the hollow channel and the pressure chamber between the first connecting end and the second connecting end, in particular between the first connecting end and the pressure chamber. In particular, the pressure measuring channel branches off from the hollow channel between the first connecting end and the pressure chamber. In particular, the pressure measuring channel then makes it possible, in a particularly simple manner, to detect, in particular measure, the pressure in the hollow channel, the pressure chamber, and thus simultaneously the pressure in the interior of the medical hollow body.

[0018] According to a further development of the invention, the pressure measuring channel is configured to accommodate a pressure measuring device. Thus, it is advantageously—particularly in a simple manner—possible to connect a pressure measuring device to the pressure measuring channel, in particular to fluidically connect it, in order to determine the pressure in the pressure measuring channel and thus simultaneously in the hollow channel, the pressure chamber, and the medical hollow body. Preferably, the pressure measuring channel has a thread or a thread is assigned to the pressure measuring channel, wherein the pressure measuring device can be screwed to the thread. This represents a particularly simple and easy-to-establish connection between the pressure measuring device and the pressure measuring channel.

[0019] Alternatively or additionally, it is preferably provided that a pressure measuring device, in particular a manometer, is operatively connected to the pressure measuring channel in order to measure the pressure in the pressure measuring channel. In this way, the pressure in the hollow channel, the pressure chamber, and in the medical hollow body can be determined simultaneously.

[0020] According to a further development of the invention, a piston is displaceably arranged in the pressure chamber, so that the volume of the pressure chamber can be changed by displacing the piston. In this way, the pressure in the pressure chamber can be adjusted very easily by displacing the piston. In particular, the piston is arranged so that it can be displaced linearly in the pressure chamber, preferably in the axial direction. The piston preferably lies tightly against an inner circumferential surface of the pressure chamber, so that when the piston is displaced in the pressure chamber, the pressure in the chamber changes.

[0021] An axial direction is preferably in particular a direction that extends parallel to or in the direction of the longitudinal axis of the hollow channel. The longitudinal axis of the hollow channel, in the assembled state, is preferably aligned with the longitudinal axis of the medical hollow body. The longitudinal axis of the hollow channel, in the assembled state, is preferably aligned with the displacement axis of the active end of the tension / compression measuring device. In a particularly preferred embodiment, the axial direction thus extends both along the longitudinal axis of the hollow channel and along the longitudinal axis of the medical hollow body, as well as along the displacement direction of the active end of the tension / compression measuring device. A radial direction is perpendicular to the axial direction. A circumferential direction encompasses the axial direction concentrically.

[0022] According to a further development of the invention, the adapter part comprises a piston configured to be displaceably arranged in the pressure chamber. The piston can thus be provided separately from the pressure chamber, at least in the unassembled state, and can be displaceably arranged therein as needed in order to change the volume of the pressure chamber by displacing the piston, thereby simultaneously changing the pressure in the pressure chamber. In particular, the piston is preferably operatively connected to the active end of the tension / compression measuring device.

[0023] However, it is also possible that the piston is held captive in the pressure chamber.

[0024] According to a further development of the invention, the piston comprises a piston disc. Alternatively, the piston may be designed as a piston disc. The latter represents a particularly simple piston configuration. In this case, it is particularly possible for the active end of the tension / compression machine to act on the piston, which is designed as a piston disc, to displace it in the pressure chamber.

[0025] If the piston has a piston disc, it preferably also has a piston rod that is connected to the piston disc, in particular is formed integrally with the piston disc. The piston rod preferably protrudes partially from the pressure chamber in order to be connected to the active end of the tension / pressure measuring device. If the piston rod protrudes through an opening, in particular an axial opening, whose inside diameter is smaller than the diameter of the piston disc, the piston is captively arranged in the pressure chamber, wherein the part of the piston rod arranged outside the pressure chamber can simultaneously be connected to the active end of the tension / pressure measuring device.

[0026] Alternatively or additionally, the piston has a coupling part designed to be mechanically coupled to the active end of the tension / compression measuring device. In particular, the piston rod may have the coupling part. If the piston is mechanically coupled to the active end by the coupling part, it can be displaced together with the active end.

[0027] Preferably, a securing bore, preferably a transverse bore extending transversely, in particular perpendicular to the axial direction, is arranged on the coupling part of the piston for the passage of a securing pin. Thus, the coupling shaft can be connected particularly securely to the active end of the tension / compression measuring device by inserting a securing pin through the securing bore. The active end of the tension / compression measuring device preferably has a securing receptacle for the securing pin, so that, in the assembled state, the pin engages through the securing receptacle on the one hand and the securing bore on the other, thus securely holding the piston to the active end.

[0028] According to a preferred embodiment, the coupling part is designed as a coupling shaft. A coupling shaft is understood to mean, in particular, a shaft of the piston that is specifically designed for mechanical coupling with the active end. In particular, the piston rod is preferably designed as a coupling shaft.

[0029] According to a further development of the invention, a scale is assigned to the pressure chamber and / or the piston, from which a current pressure in the pressure chamber can be read off depending on a current position, in particular a current axial position, of the piston in the pressure chamber. This very easily enables at least a rough estimate of the pressure in the pressure chamber, as well as a plausibility check to determine whether the pressure ultimately set / monitored during the leak test is correct.

[0030] The scale preferably allows the pressure to be read off as a function of the current position of the piston relative to a starting position of the piston on the scale. Thus, it is particularly preferred to first check from which position the piston starts on the scale under ambient pressure in the pressure chamber when it is initially displaced by the tension / compression measuring device in order to change the pressure in the pressure chamber so that it deviates from the ambient pressure. The target position of the piston on the scale, which it reaches after the displacement, then provides a measure of the pressure difference between the reached pressure and the starting pressure, i.e., the ambient pressure, relative to the starting position.

[0031] It is understood that the change in pressure upon axial displacement of the piston depends in particular on the volume of the medical hollow body, as well as the hollow channel and the pressure chamber. In this case, the volume of the medical hollow body typically varies, while the volume of the hollow channel and the pressure chamber is predetermined for a specific adapter part. It is possible for different scales to be provided on the adapter part for different medical hollow bodies to be tested. Alternatively, it is possible for a conversion table to be provided which takes into account the volume of the medical hollow body currently being tested. Alternatively, it is possible for different adapter parts - in particular with different scales - to be provided for different medical hollow bodies.

[0032] The scale is preferably arranged on a wall of the pressure chamber. Particularly preferably, the wall of the pressure chamber is transparent, at least in the area of ​​the scale, so that the position of the piston relative to the scale can be observed through the wall. If the scale is assigned to the piston, the wall of the pressure chamber preferably has a reading mark.

[0033] The test setup also includes a tension / compression measuring device.

[0034] The tension / compression measuring device has a stationary body and an active end that is axially displaceable relative to the stationary body, in particular an axially displaceable measuring element. The tension / compression measuring device is configured in particular as already explained above in connection with the adapter part. The test arrangement also has an adapter part according to the invention or an adapter part according to one of the previously described embodiments. The second connecting end of the adapter part is operatively connected to the active end in such a way that a pressure in the pressure chamber of the adapter part can be adjusted by axially displacing the active end relative to the pressure chamber. In connection with the test arrangement, the advantages that were already explained in connection with the adapter part arise in particular.

[0035] The tension / compression measuring device preferably has a drive, in particular a mechanical or motor drive, for displacing the active end. In a particularly preferred embodiment, the drive is designed as an electric motor – optionally with an intermediary gear. The drive can in particular be assigned to the base body or arranged in the base body.

[0036] The active end is preferably axially displaceable on a measuring tower of the base body. It is possible for at least parts of the drive to be arranged in the measuring tower or integrated into the measuring tower. The active end is axially displaceable, in particular, relative to the measuring tower and on the measuring tower.

[0037] According to a further development of the invention, the stand body comprises a fastening part for securing the adapter part relative to the stand body. In particular, the fastening part is configured to be fastened to the stand body on the one hand and to be rigidly connected to the adapter part on the other hand, so that the adapter part is ultimately arranged in a rigid manner relative to the stand body via the fastening part.

[0038] The stand body preferably also has a test body fastening part for securing the medical hollow body relative to the stand body. Preferably, the test body fastening part is, on the one hand, positionally fixed to the stand body, and, on the other hand, the medical hollow body is positionally fixed to the test body fastening part, so that ultimately the medical hollow body is arranged positionally fixed relative to the stand body via the test body fastening part.

[0039] According to a further development of the invention, the active end, in particular the measuring element, is connected to the piston, in particular the piston disc, of the adapter part in a tension- and / or pressure-transmitting manner. A pressure-transmitting connection can be achieved particularly easily by the active end pressing on the piston disc without otherwise being mechanically connected to it. However, it is also possible for the active end to be connected to the piston disc in a tension- and pressure-transmitting manner, for example, by being latched to the piston disc or mechanically connected to it in some other way.

[0040] Alternatively, it is preferably provided that the acting end is mechanically coupled—in particular rigidly—to a coupling part of the piston. The coupling part can, in particular, be a coupling shaft. It is possible for the acting end to be secured to the coupling part via a locking pin, wherein the locking pin preferably extends through a locking bore in the coupling part and a locking receptacle on the acting end.

[0041] Alternatively, it is preferably provided that the acting element itself is arranged as a piston in the pressure chamber so that it can be displaced. In particular, it is possible for the dimensions of the pressure chamber, in particular its diameter, to be matched to the acting element in such a way that the acting element itself can be used as a piston and displaced directly within the pressure chamber—without further coupling to a separate piston—in order to change the pressure in the pressure chamber. This represents a particularly simple design with a particularly small number of parts.

[0042] According to a further development of the invention, the tension / pressure measuring device comprises a control device configured to be operatively connected to a pressure measuring device, in particular a manometer, and to detect a pressure in the hollow channel, in particular in the pressure measuring channel, preferably detecting it in a time-dependent manner, and preferably evaluating it. This enables an at least partially automated performance of a leak test, wherein the detection and preferably evaluation of the pressure in the hollow channel, in particular in the pressure measuring channel, can be performed by the control device of the tension / pressure measuring device.

[0043] Preferably, the active element can be displaced by the control device depending on the detected pressure. This enables automatic adjustment of the pressure, in particular to a preset or target value.

[0044] According to a further development of the invention, the control device is configured to automatically perform a leak test or a leak check on a hollow medical body. This enables a particularly simple, time- and personnel-saving execution of the leak test. Preferably, the pressure in the pressure chamber is first automatically adjusted, then recorded over a predetermined period of time, and finally, the pressure recorded during the predetermined period, in particular the pressure curve, is evaluated.

[0045] Alternatively, it is possible for the control device to be configured to regulate the pressure in the hollow channel, in particular in the pressure-measuring channel, wherein, in particular, the active end is displaced as a function of the detected pressure in such a way that the pressure in the hollow channel, in particular in the pressure-measuring channel, is kept constant. It is then possible to determine whether the medical hollow body is leak-tight or leaky depending on control interventions performed during a predetermined period of time, in particular depending on a displacement path of the active end.

[0046] The object is also achieved by providing a method according to claim 10 for testing the tightness of a medical hollow body with a testing arrangement according to one of claims 1 to 9, wherein a medical hollow body is connected to a tension / compression measuring device via an adapter part according to the invention or an adapter part according to one of the previously described embodiments. The medical hollow body is closed in particular at its end facing away from the adapter part, in particular by means of a plug or closure. Ultimately, the method enables a test of the tightness of the plug or closure at the end of the medical hollow body that is facing away from the adapter part. A specific pressure is set in the interior of the medical hollow body by displacing the active end of the tension / compression measuring device.In this case, an overpressure or a negative pressure can preferably be set, particularly depending on the leak test to be conducted. The active element is displaced, in particular, relative to the adapter part and relative to the medical hollow body. A momentary pressure inside the medical hollow body is recorded over a specific test time. In connection with the method, the advantages already described above are particularly realized.

[0047] Preferably, the procedure is carried out in accordance with the requirements of the standard DIN EN ISO 80369-20:2015.

[0048] Preferably, the instantaneous pressure in the interior is recorded by the tension / compression measuring device during the specified test time. Preferably, the recorded instantaneous pressure is evaluated—in particular as a pressure profile over time. The evaluation is preferably performed by the tension / compression measuring device, in particular by the control device of the tension / compression measuring device.

[0049] According to a further development of the invention, the active element is held stationary after the specific pressure has been set and during the specific test time. In this case, a specific pressure is initially set, and then a check is carried out to determine whether the pressure changes more during the specific test time than is permitted according to a target value. If the pressure change remains within the target value, the tested medical hollow body is considered to be leak-tight. If the pressure change exceeds the target value, the tested medical hollow body is considered to be leak-tight. The active element is held stationary, in particular relative to the adapter part and the medical hollow body.

[0050] Alternatively, the pressure in the medical hollow body can be regulated to the specified pressure as the target value during the specified test time. Control interventions, particularly displacements of the active end, are evaluated during the specified test time, and these control interventions and / or displacements of the active end are ultimately used to determine the tightness of the medical hollow body. If the control interventions and / or displacements of the active end exceed a target value, the medical hollow body is considered leaky; otherwise, it is considered tight.

[0051] Preferably, the method is performed automatically by the tension / compression measuring device. In particular, this requires at most a manual connection of the medical hollow body to the tension / compression measuring device via the adapter part. Furthermore, the specific pressure can be automatically set by the tension / compression measuring device, and the current pressure inside the medical hollow body can be automatically recorded and preferably evaluated over the specific test time. Accordingly, automatic readjustment of the specific pressure and an evaluation of the required control interventions and / or displacements of the active end can also be performed.

[0052] According to a further development of the invention, the medical hollow body is tested before a medical plug is arranged in the medical hollow body. In particular, the medical hollow body is tested before a center plug—for a two-chamber hollow body—or an end plug is / are arranged in a syringe or carpule. At the time of testing, the medical hollow body is thus free of any plug that can be displaced within the interior of the medical hollow body, in particular free of a center and / or end plug.

[0053] The leak test of the medical hollow body can be performed, in particular, before siliconization of the inner wall of the medical hollow body, but also after siliconization. The test before siliconization is possible because the leak test is performed without a plug that can be moved inside the medical hollow body. This allows for an earlier leak test in the manufacturing process of the medical hollow body, which offers logistical advantages. Because the leak test can be performed without a plug, the test results are not influenced by the breakaway and / or sliding friction forces of such a plug.

[0054] Finally, the object is also achieved by providing a use of a test assembly according to one of claims 1 to 9 for testing the tightness of a medical hollow body. In accordance with the present disclosure, a tension / compression measuring device can advantageously be used to test the tightness of a medical hollow body. In particular, the advantages already mentioned are realized in this case.

[0055] The invention is explained in more detail below with reference to the drawings, which show: Figure 1 shows a schematic representation of a first embodiment of a test arrangement with an embodiment of an adapter part; Figure 2 shows a schematic sectional representation of the test arrangement according to Figure 1 , and Figure 3 shows a schematic representation of a second embodiment of a test arrangement.

[0056] Fig. 1shows a representation of a first embodiment of a test arrangement 1, which has a tension / compression measuring device 3. The tension / compression measuring device 3 in turn has a stand body 5 and a relative to the stand body 5 axially, that is to say with respect to Figure 1 in the vertical direction, displaceable active end 7. Furthermore, the test arrangement 1 has an adapter part 9, which is designed to connect a medical hollow body 11 to the tension / compression measuring device 3. The adapter part 9 has a first, in Figure 2 shown connecting end 13, which is designed to connect the adapter part 9 fluid-tight with a Figure 2illustrated interior 15 of the medical hollow body 11. The adapter part 9 also has a second connection end 17. The second connection end 17 has a pressure chamber 19 and is configured to operatively connect the adapter part 9 to the tension / pressure measuring device 3 such that a pressure in the pressure chamber 19 can be adjusted by means of the tension / pressure measuring device 3.

[0057] The adapter part 9 also has a hollow channel 21 which passes through it from the pressure chamber 9 to the first connection end 13.

[0058] In addition, the embodiment of the adapter part 9 shown here has a pressure measuring channel 23 which branches off from the hollow channel 21 or the pressure chamber 19, here from the hollow channel 21, between the first connecting end 13 and the second connecting end 17.

[0059] The second connection end 17 is operatively connected to the acting end 7 of the tension / pressure measuring device 3 such that a pressure in the pressure chamber 19 can be adjusted by axially displacing the acting end 7 relative to the pressure chamber 19.

[0060] In this way, a precise pressure setting in the pressure chamber 19 and thus ultimately also in the interior 15 of the medical hollow body 11 can be carried out in a simple manner using the tension / compression measuring device 3, which can be used for a leak test of the medical hollow body 11. Thus, it is ultimately possible to use a device for this leak test that is already used for testing medical hollow bodies 11, namely the tension / compression measuring device 3, which is regularly used, for example, to measure tear-off forces or displacement forces of plugs in medical hollow bodies 11.

[0061] The base body 5 preferably has a measuring tower 25 on which the active end 7 is displaceable. For this purpose, the tension / compression measuring device 3 preferably has a drive 27 configured to displace the active end 7 in the axial direction, in particular on the measuring tower 25.

[0062] The active end 7 is preferably designed as a measuring element or has a measuring element. However, it is also possible for the active end 7 to be designed purely as a mechanical component or mechanical adapter, in particular as a mechanical connecting part for attaching additional parts, in particular measuring arrangements, for example load cells, to the tension / compression measuring device 3.

[0063] The first connecting end 13 is preferably assigned a sealing device 29, which is configured to seal the fluidic connection between the hollow channel 21 and the interior 15 of the medical hollow body 11. For this purpose, the sealing device 29 preferably has at least one sealing element, specifically two sealing rings 31, 31', which are arranged at the first connecting end 13, in particular encompassing the first connecting end 13 in the circumferential direction.

[0064] The hollow channel 21 is open, in particular, at the first connecting end 13. In particular, it opens into the first connecting end 13, or it opens into the interior 15 of the medical hollow body 11 in the region of the first connecting end 13 when the adapter part 9 is connected to the medical hollow body 11.

[0065] By means of the tension / pressure measuring device 3 and the adapter part 9, both an overpressure and a negative pressure - compared to an ambient pressure in an environment of the medical hollow body 11 - can be set in the interior 15 of the medical hollow body 11.

[0066] A pressure measuring device 33, which can be designed in particular as a manometer, is arranged on the pressure measuring channel 23. The pressure measuring channel 23 is preferably configured for connection to the pressure measuring device 33, for example by having a thread into which the pressure measuring device 33 can be screwed or onto which the pressure measuring device 33 can be screwed.

[0067] The pressure measuring device 33 is operatively connected to the pressure measuring channel 23 in order to measure a pressure in the pressure measuring channel 23 - and thus simultaneously in the hollow channel 21, the pressure chamber 19 and in the medical hollow body 11.

[0068] Alternatively, the pressure measuring device can also be connected to a distal end of the hollow body 11 in order to measure the pressure inside the hollow body 11. In this case, an adapter part 9 can also be used which does not have a pressure measuring channel 23, or in which the pressure measuring channel 23 is closed, for example, with a blind plug.

[0069] A distal end is understood here in particular to mean an end of the hollow body 11 which, when the hollow body 11 is used, is intended to face a patient and / or an injection site and preferably faces away from a user of the hollow body 11. The other end of the hollow body 11 is referred to as the proximal end.

[0070] A piston 35 is displaceably arranged in the pressure chamber 19 such that a volume of the pressure chamber 19 can be changed by displacing the piston 35. Alternatively, it is also possible for the adapter part 9 to have a piston that is designed to be displaceably arranged in the pressure chamber 19. The piston 35 therefore does not have to be arranged permanently in the pressure chamber 19, in particular there is no need for a captive, possibly inseparable arrangement of the piston in the pressure chamber 19. However, it is possible for the piston 35 to be arranged permanently, in particular captive, in the pressure chamber 19.

[0071] The piston 35 preferably has a piston disc 37. This is preferably arranged in a sealed manner in the pressure chamber 19, preferably by means of at least one sealing ring, which the piston disc 37 carries, in particular, on its circumference. According to one embodiment, it is possible for the piston 35 to be designed entirely as a piston disc 37. In this case, the acting end 7 preferably acts directly on the piston disc 37.

[0072] In the embodiment illustrated here, however, the piston 35 has a coupling part 39 that is designed to be mechanically coupled to the active end 7. The coupling part 39 is designed, in particular, as a coupling shaft. This is preferably rigidly, in particular entrainably, connected to the coupling disc 37. In particular, it is possible for the coupling part 39 and the coupling disc 37 to be formed integrally, in particular of the same material, and thus together form the piston 35 in one piece.

[0073] If the coupling part 39 is coupled to the active end 7, they can be displaced together, so that the piston 35 is displaced together with the active end 7 when displaced. In this way, the volume in the pressure chamber 19 can be adjusted by displacing the active end 7 and thus also the piston 35. This simultaneously leads to an adjustment of the pressure in the hollow channel 21 and in the medical hollow body 11 when the latter is connected to the adapter part 9.

[0074] In the exemplary embodiment illustrated here, the pressure chamber 19 is assigned a scale 41, from which a current pressure in the pressure chamber 19 can be read as a function of a current - axial - position of the piston 35 in the pressure chamber 19. In particular, the scale 41 is preferably arranged on an outer circumference of the pressure chamber 19, in particular glued or printed thereon, or attached in another suitable manner so that it can be read. In particular, a wall of the pressure chamber 19 is preferably transparent, at least in the region of the scale 41, so that the position of the piston 35 relative to the scale 41 can be observed through the wall of the pressure chamber 19.

[0075] Alternatively, it is possible for a corresponding scale to be assigned to the piston 35. The wall of the pressure chamber 19 then preferably has a reading mark.

[0076] According to a preferred embodiment, the stand body 5 has a fastening part 43, which is designed to fasten the adapter part 9 relative to the stand body 5 and preferably to the stand body 5. However, it is also possible for the adapter part 9 to be held in a particularly simple manner, on the one hand, by the active end 7 and, on the other hand, by the medical hollow body 11.

[0077] The medical hollow body 11 is arranged here in a holder 45, which is essentially designed as a cylindrical hollow body into which the medical hollow body 11 can be inserted. In this exemplary embodiment, the medical hollow body 11 rests with a finger rest 47 on an upper edge 49 of the holder 45. The holder 45, in turn, is secured to a mounting base 51 of the tension / compression measuring device 3, which can preferably be part of the stand body 5.

[0078] The fastening part 43 can also be connected to the holder 45 and / or the fastening foot 51.

[0079] As already explained, the acting end 7 is mechanically coupled here to the coupling part 39 of the piston 35. Alternatively, however, it is also possible for the acting end 7 to be connected directly to the piston disc 37 or to a piston disc that is not assigned a coupling part 39, in a tension- and / or pressure-transmitting manner. In particular, the acting end 7 can act directly on the piston disc 37. Furthermore, it is alternatively possible for the acting end 7 itself to be displaceable as a piston in the pressure chamber 19.

[0080] The tension / pressure measuring device 3 preferably has a control device 53, which is configured to be operatively connected to the pressure measuring device 33 and to detect a pressure in the hollow channel 21, in particular in the pressure measuring channel 23, preferably in a time-dependent manner. The control device 53 is further preferably configured to evaluate the detected pressure, in particular in a time-dependent manner. According to a preferred embodiment, it is possible for the control device 53 to be further configured to displace the acting end 7 depending on the detected pressure, in particular in order to be able to automatically adjust the pressure in the hollow channel 21 and ultimately in the medical hollow body 11, in particular to a predetermined pressure value. It is also possible for the control device 53 to be configured, according to a preferred embodiment, to regulate the pressure in the hollow channel 21 to a predetermined target value.The control device 53 is also configured to automatically carry out a leak test of the medical hollow body 11.

[0081] Fig. 2 shows a schematic sectional view of the test arrangement 1 according to Figure 1 Identical and functionally identical elements are provided with the same reference symbols in all figures, so that reference is always made to the preceding description.

[0082] The coupling part 39 here has, in particular, a transverse bore 55 as a securing bore, which, in the assembled state, is aligned with a securing receptacle 57 of the active end 7. A securing pin 59 is inserted through the transverse bore 55 and the securing receptacle 57, which is preferably also designed as a transverse bore, through which the piston 35 is ultimately mechanically connected to the active end 7.

[0083] In an analogous manner, the holder 45 is also connected to the fastening foot 51 via a second locking pin 61.

[0084] The medical hollow body 11 is here closed at its distal end with a closure 63, in particular fluid-tight.

[0085] The medical hollow body 11 preferably does not rest tightly with its finger rest 47 on the upper edge 49 of the holder 45, or the holder 45 has at least one pressure equalization bore that enables pressure equalization with an external environment of the holder 45. This preferably ensures that the interior of the holder 45 always has ambient pressure, which allows the most accurate testing of the tightness of the medical hollow body 11.

[0086] Fig. 3 shows a schematic representation of a second embodiment of a test arrangement 1. Here, the fastening part 43 is connected to the holder 45.

[0087] The following with reference to all Figures 1 to 3 The method for testing the tightness of the medical hollow body explained in more detail serves in particular to test the tightness of the closure 63, that is to say in particular the connection of the closure 63 to the medical hollow body 11.

[0088] According to a preferred embodiment, the medical hollow body 11 is tested for leaks using the test assembly 1 in the following manner: First, the medical hollow body 11 is connected to the tension / compression measuring device 3 via the adapter part 9. The medical hollow body 11 is closed, in particular, at its distal end, here by means of the closure 63. A specific pressure is then set in the interior 15 of the medical hollow body 11 by displacing the active end 7, and a current pressure in the interior 15 is recorded over a specific test time. This pressure recording takes place—preferably time-dependent—preferably by means of the tension / compression measuring device 3, in particular by its control device 53.

[0089] The pressure thus detected is preferably evaluated, particularly preferably also by the tension / pressure measuring device 3, in particular by its control device 53.

[0090] Preferably, the active element 7 is held stationary after the specific pressure has been set and during the specific test time. It is then detected, in particular, whether the pressure in the interior 15 changes, in particular whether it increases, especially if a negative pressure was previously set in the interior 15, or whether it decreases, especially if an overpressure was previously set in the interior 15. Based on the detected pressure change, conclusions can then be drawn about a leakage rate and / or the tightness of the medical hollow body 11.

[0091] However, it is also possible for the pressure in the interior 15 to be regulated over the specific test time by the tension / pressure measuring device 3, in particular the control device 53, in particular to a predetermined target pressure value. In this case, the control signals or travels of the tension / pressure measuring device 3, in particular of the active end 7, can be evaluated with regard to a leakage rate and thus ultimately the tightness of the medical hollow body 11. In this respect, it is obvious that greater adjustment effort is required if the medical hollow body 11 is leaking, or that the adjustment effort is greater the higher the leakage rate. In the optimal case, with a vanishing leakage rate, no adjustment is required.

[0092] The method for testing the tightness of the medical hollow body 11 is preferably carried out automatically or in an automated manner by the tension / compression measuring device 3, in particular without requiring any intervention by a user.

[0093] The medical hollow body 11 is preferably tested before a medical plug, in particular a center and / or end plug, is arranged in the medical hollow body 11. The medical hollow body 11 can be tested for leaks, in particular before or after siliconization. Such siliconization is carried out, in particular, to increase the sliding properties of a center and / or end plug in the interior 15 of the medical hollow body 11.

[0094] It is clear that according to the technical teaching disclosed here, in particular a tension / compression measuring device 3 is used to test the tightness of a medical hollow body 11.

Claims

1. Test assembly (1), comprising - a tension / pressure measuring device (3) and comprising - an adapter part (9) for connecting a medical hollow body (11) to the tension / pressure measuring device (3), wherein - the adapter part (9) comprises: o a first connecting end (13), which is designed to connect the adapter part (9) to an interior (15) of a medical hollow body (11) in a fluid-tight manner, and o a second connecting end (17), which has a pressure chamber (19) and is designed to operatively connect the adapter part (9) to the tension / pressure measuring device (3), so that a pressure in the pressure chamber (19) can be adjusted by means of the tension / pressure measuring device (3), wherein - a hollow channel (21) passes through the adapter part (9) from the pressure chamber (19) to the first connecting end (13), characterised in that - the tension / pressure measuring device (3) has a standing body (5) and a working end (7), which can be axially displaced relative to the standing body (5), wherein - the second connecting end (17) of the adapter part (9) is operatively connected to the working end (7) in such a way that a pressure in the pressure chamber (19) can be adjusted by axially displacing the working end (7) relative to the pressure chamber (19).

2. Test assembly (1) according to claim 1, characterised by a pressure measuring channel (23), which branches off from the hollow channel (21) or the pressure chamber (19) between the first connecting end (13) and the second connecting end (17), wherein preferably a) the pressure measuring channel (23) is designed for the arrangement of a pressure measuring device (33) on the pressure measuring channel (23), and / or b) a pressure measuring device (33) is operatively connected to the pressure measuring channel (23) in order to measure a pressure in the pressure measuring channel (23).

3. Test assembly (1) according to any of the preceding claims, characterised in that a) a piston (35) is displaceably arranged in the pressure chamber (19), so that a volume of the pressure chamber (19) can be changed by displacing the piston (35), or in that b) the adapter part (9) has a piston (35), which is designed to be displaceably arranged in the pressure chamber (19).

4. Test assembly (1) according to any of the preceding claims, characterised in that the piston (35) a) has a piston disk (37) or is designed as a piston disk (37), and / or b) has a coupling part (39), which is designed to be mechanically coupled to the working end (7) of the tension / pressure measuring device (3).

5. Test assembly (1) according to any of the preceding claims, characterised in that the pressure chamber (19) and / or the piston (35) is assigned a scale (41) from which an instantaneous pressure in the pressure chamber (19) can be read depending on an instantaneous position of the piston (35) in the pressure chamber (19).

6. Test assembly (1) according to any of the preceding claims, characterised in that the standing body (5) has a fastening part (43) for fixing the adapter part (9) relative to the standing body (5).

7. Test assembly (1) according to any of the preceding claims, characterised in that the working end (7) is a) connected to a piston disk (37) of the adapter part (9) in a tension- and / or pressure-transmitting manner, or b) mechanically coupled to a coupling part (39) of the piston (35), or c) arranged displaceably as a piston in the pressure chamber (19).

8. Test assembly (1) according to any of the preceding claims, characterised in that the tension / pressure measuring device (3) has a control device (53), which is designed to be operatively connected to a pressure measuring device (33) and to record and preferably evaluate a pressure in the hollow channel (21).

9. Test assembly (1) according to any of the preceding claims, characterised in that the control device (53) is designed to carry out a tightness test of a medical hollow body (11) in an automated manner.

10. Method for testing the tightness of a medical hollow body (11) using a test assembly according to any of the preceding claims, comprising the following steps: - connecting a medical hollow body (11) to the tension / pressure measuring device (3) via the adapter part (9); - setting a specific pressure in an interior (15) of the medical hollow body (11) by displacing the working end (7) of the tension / pressure measuring device (3) and - recording an instantaneous pressure in the interior (15) over a specific test time.

11. Method according to claim 10, characterised in that the working end (7) is kept still after the specific pressure has been set and during the specific test time.

12. Method according to any of claims 10 or 11, characterised in that the method is carried out automatically by the tension / pressure measuring device (3).

13. Method according to any of claims 10 to 12, characterised in that the medical hollow body (11) is checked before a medical stopper is arranged in the medical hollow body (11).

14. Use of a test assembly (1) according to any of claims 1 to 9 to test the tightness of a medical hollow body (11).