Test specimen for a medical cleaning device

Abstract

Test body (10) for a medical cleaning device, in particular for testing its effectiveness in a cleaning, sterilization or disinfection process, comprising at least: - a coupling element (15) for connecting the test specimen (10) to the medical hygiene cleaning device, and - a fluid-conducting connection of one of the coupling elements (15) with an inlet opening (12.1, 13.1) of at least one test tube (12, 13); characterized in that - that at least one test tube (12, 13) is formed as a partially transparent plastic hose line, at least over part of its length; - that a liquid-tight connection is formed at the base (14) and at the coupling element (15) with one end of the test tube (12, 13) and - that the test tube (12, 13) extends through a cavity of a base body (11) that is at least partially transparent.

Description

[0001] The invention relates to a test body for a medical cleaning device, in particular for testing the effectiveness in a cleaning, sterilization or disinfection process, with the features of the preamble of claim 1.

[0002] Medical cleaning equipment of this type includes, for example, devices used to reprocess handpieces and contra-angles in dental technology. These instruments have internal cavities and fluid channels with narrow passages, angles, and undercuts that are difficult to clean. Contaminants such as blood, saliva, tissue, rust, silicates, oil, and mechanical abrasion particles may be present. Cleaning processes are performed to remove these contaminants. The effectiveness of the cleaning, sterilization, and / or disinfection processes, which are automated by the cleaning equipment, must be regularly monitored, regulated, and are subject to inspection by the authorities.

[0003] To test the effectiveness of the cleaning, disinfection and / or sterilization process, the cleaning device must be tested with a real load contaminated by clinical use and must include, in particular, products that are considered difficult to clean, such as the dental handpieces and contra-angles mentioned above.

[0004] Detecting residual substances that may remain on the instrument after reprocessing would not be economical for real instruments due to the high number / repetition of tests required. Therefore, test specimens may be used as a supplement.

[0005] A test specimen depicted on the website https: / / valitech.de / dienstleistungen-und-produkte / unsere-leistungen / is known. It includes an adapter element for connection to the hygiene cleaning device and two insertable metal tubes. The tubes are also connected to a sheet metal blank intended to provide a surface for testing external cleaning. This known test specimen is inadequate for comprehensively verifying the effectiveness of the reprocessing. It lacks a three-dimensional structure. The surface for testing external cleaning, a simple stainless steel sheet, is too smooth. Since the sheet metal blank lacks any grinding, knurling, or similar features on its exterior, the known test specimen does not have areas that are difficult to clean, unlike the medical instruments themselves.

[0006] A further disadvantage is that the test specimen must be assembled from several components and disassembled again after the process, creating potential sources of error and non-reproducible influences. Finally, the test specimen itself must be very thoroughly cleaned after the validation and cleaning cycles to ensure that no organic residues remain that could distort the results of a subsequent test. The mechanically complex construction using stainless steel components makes the test specimen expensive and, for economic reasons, precludes single-use applications. Visual inspection is not possible due to the metallic material.

[0007] Another test piece for use in a cleaning, sterilization, or disinfection process is known from DE 10 2016 120 127 A1. This patent explicitly describes the use of PTFE tubing, which is widely used in medical technology, as disadvantageous. Instead, the test piece is to include at least one cannula made of stainless steel. A screw-on connection device is provided for connecting it to a cleaning and / or sterilization and / or disinfection device, in particular an autoclave, combination autoclave, or the like. The cannula can be arranged within a sleeve, which is designed as a cylindrical body made of stainless steel and sealed with two caps on the cylinder bases. Here, too, single-use is not economical due to the choice of material.

[0008] The object of the present invention is therefore to improve a test body of the type mentioned at the outset for a medical cleaning device or other reprocessing device, in such a way that, firstly, problem areas during cleaning on the test body are more similar to the problem areas that exist on medical instruments actually to be cleaned, and secondly, that a cost-effective design allows for single-use use of the test body.

[0009] This task is solved by a test specimen with the characteristics 1.

[0010] According to the invention, a three-dimensional test object is created whose dimensions are based on those medical tools and equipment which are to be processed.

[0011] For the purposes of the present invention, the term "cleaning device" refers to all devices suitable for cleaning, sterilizing or disinfecting medical and dental tools and other equipment.

[0012] According to the invention, the base body is a hollow body, preferably made of a transparent plastic, in particular polycarbonate. This makes it possible to manufacture the base body as a one-piece injection-molded part. The finished base body should be transparent at least partially on its outer circumference, so that at least one transparent viewing window remains, allowing visual inspection of the test tubes running inside.

[0013] At least one test tube is guided through the base body, which, according to the invention, is preferably made of an at least partially transparent plastic, such as PTFE in particular. The inherently flexible hose section from which the test tube is formed is dimensioned such that it is clamped in a port at both the inlet and outlet openings and runs through the interior of the base body in a fixed, extended position. Viewed from the outside through the transparent wall of the base body, the hose sections therefore appear as rigid test tubes. "Partially transparent" means that not only clear materials but also slightly cloudy materials can be used, as long as any deposits in the lumen of the hose used as a test tube remain visible from the outside.

[0014] Due to the at least partially transparent or semi-transparent design of the base body and the test tube, it is visually apparent whether the test specimen is soiled and therefore ready for use in a test cycle of a cleaning, sterilization, or disinfection process. Furthermore, any remaining soiling after the reprocessing procedures can be visually identified immediately, without the need for complex laboratory analyses. It is also possible to differentiate between internal and external soiling and, in the event of any problems with the cleaning device, to identify the affected treatment step.

[0015] In a preferred embodiment, the base body is either formed in at least two parts or has a tubular end open at one end, which can be closed with a plug-like closure element. The test tube is preferably inserted at one end firmly into a port, which is formed either on one side of the base body or on the closure element. This port provides a secure clamping mechanism for the test tube. During assembly, the test tube is first inserted into this port.

[0016] Another advantageous embodiment provides that the test tube is sealed against the port by means of an O-ring.

[0017] In a preferred embodiment, a port is also formed on the opposite side of the base body, which has a threading section with a diameter larger than the outer diameter of the test tube. The threading section has a converging cross-section and is, for example, funnel-shaped to facilitate threading the free end of the test tube during assembly.

[0018] The port following the threading section preferably has an inner diameter in a subsequent sealing section that is precisely matched to the outer diameter of the test tube, so that a sealing effect is achieved in this sealing section and no liquid from the cleaning process can enter the cavity between the wall of the base body and the at least one test tube.

[0019] It is also possible that the ports have a threading section on both sides.

[0020] Another preferred embodiment provides that the at least one test tube has a specific ratio of wall thickness to length, taking into account the material-specific modulus of elasticity, so that it can be mounted in an extended position within the base body by being firmly clamped and supported in a port on one side and then being inserted into the other port with the threading section.

[0021] The shape described above, with a threading section, is advantageous not only for practical reasons but also for the mechanical reasons described below: For an elongated body clamped at one end, which is free on the unclamped side and is compressed there by a force, Euler's buckling case I applies. This would be the case if the free end of the test tube does not thread precisely into the opening of the port and its end face abuts next to the opening of the port. The critical buckling force in this case is calculated as follows: Fcrit=π24L2El where E is the modulus of elasticity and I is the axial area moment of inertia of the cross-section.

[0022] For an elongated body that is fixed at one end, guided on the unfixed side, and compressed there by a force acting exactly in the direction of the central axis, Euler's buckling case IV applies. The critical buckling force in this case is calculated as follows: Fcrit=4π2L2El

[0023] This means that, due to the guidance and centering of the test tube in the threading section provided according to the invention, an axial force 16 times greater can be exerted on the test tube before it buckles than in the other case. Accordingly, a high force can be applied to push the free end of the test tube into its sealing seat and create a fluid-tight connection without having to carry out additional measures such as gluing or welding, etc.

[0024] According to the invention, the use of PTFE tubes and hoses, which are widely used in medical technology, is indeed possible simply through clever geometric design. The readily available and semi-transparent test tubes can be fixed and inserted into the base body in a straight position without much effort, thus refuting the prejudice against the use of PTFE hoses described in DE 10 2016 120 127 A1.

[0025] Preferably, at least two test tubes with different inner diameters are provided in the same base body. The inner diameter of one test tube is dimensioned so small that capillary action occurs with conventional cleaning agents. In contrast, the diameter of the other test tube is dimensioned so large that no capillary action occurs. The smallest and largest diameters preferably correspond to those found in channels in the medical and dental instruments and other equipment that are typically processed in the cleaning device under test. In this embodiment, an inlet distributor is formed in the base body in the area of ​​the coupling element to distribute the introduced liquid to the two test tubes.

[0026] The main body preferably terminates in a closed base, at which the outlet openings of the test tubes are arranged. In this embodiment, the main body is also open on the opposite side, allowing the insertion of a plug-like coupling element. The coupling element and the open main body can then be bonded or welded together.

[0027] The base is preferably designed as a disc, creating edge areas that overhang the outlet openings of the test tubes. This results in recesses or undercuts between the base and the lower end of the cylindrical body, allowing the cleaning of hard-to-reach areas to be simulated on the test specimen.

[0028] Due to the preferred two-part design of the test body, comprising an upwardly open base and a coupling element that can be inserted therein, various coupling elements can be combined with the same base. Only the coupling elements are specially designed with respect to an adapter section for connection with specific types of cleaning devices, so that the test body according to the invention can be manufactured cost-effectively for use with different cleaning devices.

[0029] Another preferred embodiment provides for the formation of an adhesion surface on the smooth, cylindrical plastic wall of the base body. This surface may have a rough structure that facilitates adhesion and / or makes cleaning more difficult. This allows the simulation of the knurled and / or surface-mounted grip areas of real medical instruments.

[0030] The invention is explained in more detail below with reference to the embodiment shown in the drawings. The figures show in detail: Fig. 1 a first embodiment of a test specimen in perspective view; Fig. 2. the test specimen during assembly in cross-section; Fig. 3 a detail of the base of the basic body in section; and Fig. 4. The fully assembled test specimen in longitudinal section; Fig. 5 a second embodiment of a test specimen in perspective view; Fig. 6 a coupling element for the test specimen according to the second embodiment, in perspective view;

[0031] Fig. Figure 1 shows a first embodiment of a test body 10 with a transparent base body 11 and a coupling element 15 inserted therein in a perspective view. An inlet distributor is formed inside the coupling element 15, through which a centrally supplied fluid, in particular a cleaning fluid, is distributed to the two inlet openings 12.1, 13.1 of two test tubes 12, 13. The test tubes 12, 13 run longitudinally and in an extended position through the transparent base body 11 and open at outlet openings 12.2, 13.2 on a disc-shaped base 14 at the lower end. The coupling element 15 has an adapter section 15.1 for coupling to a medical cleaning device for cleaning, sterilization and / or disinfection or reprocessing in some other way. In the illustrated embodiment, the adapter section 15.1 is designed according to the KAVO110 standard.

[0032] Fig. 2 shows the one in Fig. Figure 1 shows the test specimen 10 during assembly in a sectional view. The upper ends of the test tubes 12, 13 have already been inserted into ports 15.5, 15.6 of the coupling element 15. O-rings 15.7, 15.8 improve the seal in this area.

[0033] The base body 11 is wide open at the top. During manufacturing, the coupling element 15 with the test tubes 12, 13 is first positioned correctly and then lowered into the base body 11. The base body 11 can also be slid onto a plug section 15.3 of the coupling element 15 from below.

[0034] As shown in the enlarged section view from the area of ​​base 14 of the basic body 10 in Fig. As illustrated in Figure 3, each test tube has a conical, in particular funnel-shaped, threading section 14.1, 14.2 inside, which facilitates the threading of the lower end sections of the test tubes and which transitions into a sealing section 14.3, 14.4.

[0035] The fully assembled test specimen 10 with a coupling element 15, which has an adapter element for a KAVO110 system, shows Fig. 4 in a longitudinal section. The plug section 15.3 is inserted into the base body 11. A collar 15.4 rests on the upper edge of the base body 11. The coupling element 15 has a cavity 15.2 in its center, which opens at the inlet openings 12.1, 13.1 of the two test tubes 12, 13 and thus forms an inlet distributor.

[0036] Fig. Figure 5 shows a further embodiment of a test body 10'. This has the same transparent base body 11 as the first embodiment. The two test tubes 12, 13 are guided through the base body 11 and terminate at the base 14 at the outlet openings 12.2, 13.2 located there. At the Fig. 5. A bonding surface 19 is formed on the visible part of the outside of the wall of the base body 11.

[0037] The inlet openings 12.1, 13.1 are located in a coupling element 15', which forms an inlet distributor for the fluid inside. The adapter section 15.1' of the coupling element 15' is designed differently compared to the first embodiment of the test specimen 10. Here, it is designed as an adapter for a KAVO101 system.

[0038] Fig.Figure 6 shows the coupling element 15' with an upper section designed as an adapter section 15.1' for the KAVO101 system. Below this is a collar 15.4' intended to rest against the upper edge of the base body 11. A plug section 15.3' is inserted into the upwardly open neck of the base body 11 during manufacturing, forming a closed, hollow test specimen.

[0039] Below the plug section 15.3', two ports 15.5' and 15.6' are formed. These are each designed to receive an upper initial section of the tubular test tubes by simply inserting them, so that the inlet openings of the test tubes are also located there when they are inserted into the coupling element 15'. Reference symbol list 10, 10' test specimen 11; 11' Basic body 12, 13 test tubes 12.1, 13.1 Entrance openings 12.2, 13.2 Outlet openings 14 base 14.1, 14.2 Threading sections 14.3, 14.4 Sealing sections 15, 15' coupling element 15.1, 15.1' Adapter section 15.2 Cavity 15.3, 15.3' Plug section 15.4, 15.4' Bund 15.5, 15.6; 15.5'. 15.6' ports 15.7, 15.8 O-rings 19' adhesion area QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2016 120 127 A1 [0007, 0024]

Claims

[1] Test body (10; 10') for a medical cleaning device, in particular for testing the effectiveness in a cleaning, sterilization or disinfection process, at least comprising: - a coupling element (15; 15') for connecting the test body (10; 10') to the medical hygiene cleaning device, and - a liquid-conducting connection of one of the coupling elements (15; 15') with an inlet opening (12.1, 13.1) of at least one test tube (12, 13); characterized by , that - that the at least one test tube (12, 13) is formed as a plastic hose line which is partially transparent over at least part of its length; - that the base (14) and the coupling element (15; 15') each have a liquid-tight connection with one end of the test tube (12, 13) and - that the test tube (12, 13) extends through a cavity of a base body (11) which is at least partially transparent. [2] Test specimen (10; 10') according to claim 1, characterized by that the test tube (12, 13) extends from the coupling element first through a cavity of an at least partially transparent base body (11) and then opens with an outlet opening (12.2, 13.2) into or at a base (14) closing the cavity of the base body (11). [3] Test specimen (10; 10') according to claim 2, characterized by in that in ports (15.5, 15.6; 15.5', 15.6') at the base (14) and at the coupling element (15; 15') a port (15.5, 15.6; 15.5', 15.6') is formed, via which a liquid-tight connection with an inserted end of the test tube (12, 13) is to be formed. [4] Test specimen (10; 10') according to claim 3, characterized bythat at each of the ports (15.5, 15.6; 15.5', 15.6') there is formed a threading section (14.1, 14.2) with a diameter range which is wider than the outer diameter of the test tube (12, 13) and converges towards the outlet opening (12.2, 13.2; 12.2', 13.2'). [5] Test specimen (10; 10') according to claim 4, characterized by that between the threading section (14.1, 14.2) and the outlet opening (12.2, 13.2; 12.2', 13.2') a sealing section (14.3, 14.4, 14.4, 14.5) is formed with an inner diameter precisely matched to the outer diameter of the test tube s (12, 13). [6] Test specimen (10; 10') according to one of the preceding claims, characterized by that the base body (11) with the base (14) is formed as a one-piece injection-molded part made of thermoplastic material. [7] Test specimen (10; 10') according to claim 6, characterized bythat the base body (11) with the base (14) is made of polycarbonate (PC) and the hose line is made of polyethylene terephthalate (PTFE). [8] Test specimen (10; 10') according to one of the preceding claims, characterized by that the base body (11) is cylindrical. [9] Test specimen (10; 10') according to one of the preceding claims, characterized by that at least one undercut is formed on the base body (11). [10] Test specimen (10; 10') according to claim 9, characterized by that the base (14) has an edge projecting over the outlet openings (12.2, 13.2; 12.2', 13.2'). [11] Test specimen (10') according to one of the preceding claims, characterized by that at least one adhesion surface (19') with an increased surface roughness and / or modified surface structure compared to the rest of the housing shell is formed on the outer circumference of the base body (11'). [12] Test specimen (10') according to one of the preceding claims, characterized by that two test tubes (12, 13) are provided and that an inlet distributor for the liquid-conducting connection of an inlet channel on the coupling element (15; 15') with an inlet opening (12.1, 13.1) for each test tube (12, 13) is formed in the coupling element (15; 15'). [13] Test specimen (10; 10') according to claim 12, characterized by that a test tube (12, 13) has a diameter of at least 1.5 mm and a test tube (12, 13) is designed as a capillary tube (13) with a diameter of less than 1.5 mm.

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