Contact plate

Abstract

The invention relates to a contact plate comprising a dish (1) for receiving a nutrient medium, the dish having a base and an inner rim (2) delimiting the base. Furthermore, a lid (8) is provided which acts as an aerobic and / or anaerobic closure, can be slid over the inner rim (2) by means of a lid rim (9), and, optionally, can be locked with respect to the dish (1). The dish (1) has an outer rim (5) running coaxially around and at a distance from the inner rim (2), wherein an annular space (6) is formed between the inner rim (2) and the outer rim (5), which annular space is intended for inserting and optionally locking the lid rim (9), and wherein at least one groove (7) extending along at least portions of the circumference, or radially and / or axially oriented grooves, is / are formed on or in the base of the annular space (6), which groove(s) is / are intended for receiving a liquid, preferably in the form of condensation water, running over the inner rim (2) and / or the lid (8) and into the annular space (6).

Description

[0001] Tapping plate

[0002] The invention relates to an impression plate with a dish for receiving a nutrient medium, having a base and an inner rim defining the base, and a lid for aerobic and / or anaerobic closure, which can be placed over the inner rim with a lid edge and optionally locked against the dish, wherein the dish has an outer rim extending coaxially at a distance around the inner rim, wherein an annular space is formed between the inner rim and the outer rim, which serves for inserting and optionally locking the lid edge.

[0003] Contact plates are usually flat plastic trays filled with a sterile culture medium (e.g., Caso agar, malt extract agar, etc.). This culture medium is typically a microbiological nutrient medium used to detect microbial growth.

[0004] The underside of the tray usually has a grid pattern, which makes counting the germs easier.

[0005] Ready-to-use contact plates are known from practice, which include numerous formulations for surface monitoring, among other things in critical cleanrooms and isolators as well as in non-critical areas.

[0006] Numerous contact plates are designed similarly to Petri dishes, namely as flat, round, and transparent trays, with the lid typically fitting into the space between an inner rim that defines the interior and an outer rim that defines the base. The culture medium inside is similar to a gelatinous mass and protrudes at least slightly beyond the inner rim, allowing for contact plates to be used to sample any desired area. When ready for use, both with the lid in place and with the lid removed, there is a risk of condensation forming due to the temperature dropping below the dew point. This condensation tends to run down the sides of the contact plate, resulting in significant moisture buildup on the lower part of each plate, especially on flat surfaces, creating the impression of an unclean or even unhygienic environment.Furthermore, this negatively affects the handling of the contact plate.

[0007] The present invention therefore aims to eliminate, as far as possible, the situation caused by the formation of condensation. Since it is impossible to prevent the formation of condensation when the dew point is reached, the situation concerning the contact plate should be optimized so that condensation does not play a disruptive role during the storage and / or handling of the contact plate. Furthermore, the contact plate according to the invention should differ from competing products.

[0008] The aforementioned problem is solved by the features of claim 1. According to this claim, the generic contact plate comprises a very special design feature, namely the use of the annular space existing between the inner edge and the outer edge, which originally serves for the engagement of the lid and optionally for aerobic and / or anaerobic closure by means of a lid.

[0009] The invention is based on a surprisingly simple yet highly effective idea, namely the use of capillary action or adhesive forces, by utilizing the annular space formed between the inner and outer edges not only to collect condensation but also to bind it permanently, in that at least one groove, at least partially circumferential, is formed on or in the base of the annular space. This groove serves to collect the liquid, preferably condensation, that flows into the annular space over the inner edge and / or the lid.

[0010] It has been shown that the groove not only absorbs the liquid but also retains it effectively due to capillary action. This means that the liquid that enters and is drawn into the groove does not escape onto the surface being contacted during contact plate application, thus preventing contamination. On the contrary, once the liquid has entered the groove, it remains there, even when the contact plate is handled upside down and during the contact plate application itself. According to the invention, by providing the groove within the annular space, specifically at the bottom of the annular space, an effective measure for binding condensation or similar substances is created.

[0011] Advantageously, several grooves can be provided on or in the base of the annular space, preferably arranged coaxially with each other. For example, it is conceivable to provide two or three grooves, which may be interrupted within themselves. In principle, it is conceivable that the grooves are coaxial with each other, optionally spaced at the same distance from one another.

[0012] An interruption in the grooves may be due to the presence of clamping or locking devices near the groove base to ensure the lid is securely held in place when inserted into the annular space between the inner and outer edges. Locking mechanisms may also be provided there to selectively achieve an aerobic and / or unaerobic closure of the contact plate.

[0013] Specifically, it is conceivable that the grooves have an approximately rectangular cross-section. They can have a groove depth and width in the range of 0.3 mm to 0.7 mm, preferably about 0.5 mm.

[0014] Depending on the design of the grooves, this can result in the annular space in the base area being extremely thin. A necessary countermeasure can be achieved by providing a partial or complete reinforcement on the downward-facing outer surface of the base area of ​​the annular space, preferably on the outer surface. This reinforcement can be in the range of 0.5 mm to 1.0 mm or slightly more. Furthermore, an inwardly directed circumferential step is advantageously provided on the inner edge, on the inside, and at the free end of the inner edge. This step prevents the nutrient medium from overflowing the inner edge during filling of the tray.Ultimately, the nutrient medium, with its own surface tension, works together with the stepped upper edge area in such a way that the surface of the more or less solidified nutrient medium protrudes at least slightly beyond the upper edge area of ​​the inner rim, so that a contact plate can be pressed with the lid removed.

[0015] It should be noted at this point that the lid, with its edge area, is designed to match the depth of the annular space between the inner and outer edges in such a way that, when inserted, the inside of the lid maintains at least a slight distance from the nutrient medium, namely, it does not touch the nutrient medium.

[0016] On the inner edge, ring-shaped ridges, beads, or similar features may be provided to hold the culture medium in place. This effectively prevents the solidified culture medium from slipping or even falling out of the dish during the contact plate application process.

[0017] Furthermore, it is conceivable that a continuous step, a bead or the like is provided on the inner edge, in the area towards the bottom of the tray, which facilitates the demolding of the injection-molded tray, contributes to the stability of the tray and prevents an unwanted air space from forming in the lower edge area, i.e. in the circumferential corner area, when the nutrient medium is poured in, due to insufficient wetting, which would hinder the secure retention of the nutrient medium within the tray, especially during the contact plate process.

[0018] As previously explained, features can be provided within the annular space to position and / or lock the lid. For this purpose, the inner rim can preferably have thickenings, cams, ridges, or the like on its outer surface, extending orthogonally to the base of the tray, so that the lid can be locked in place. Similarly, locking devices can be provided in the annular space, preferably on the inside of the outer rim, which communicate with corresponding locking devices on the outside of the lid rim. The interaction of these locking devices allows for an aerobic or anaerobic closure, preferably in the form of a bayonet fitting.

[0019] The outer rim of the tray extends from below the upper free end of the inner rim to the base of the tray, thus defining a circular base. The outer rim can have an inner diameter larger than the outer diameter of the lid rim, allowing it to fit, at least slightly, over a stacked contact plate when stacking multiple closed plates. This stackability benefits both high packing density and ease of handling in the field and in the laboratory.

[0020] Furthermore, the edges taper advantageously towards their free ends, preferably conically in cross-section, which facilitates the demolding of the injection-molded parts of the impression plate. Such a conical design is advantageous for all edges.

[0021] It should be emphasized that the bowl and lid can be made from any material. Manufacturing from plastic is particularly advantageous, as the parts can be injection-molded with all integral components as described above.

[0022] There are now various ways to advantageously elaborate and further develop the teaching of the present invention. For this purpose, reference should be made, on the one hand, to the claims subordinate to claim 1 and, on the other hand, to the following explanation of a preferred embodiment of the invention with reference to the drawing. In conjunction with the explanation of the preferred embodiment of the invention with reference to the drawing, generally preferred embodiments and further developments of the teaching are also explained. The drawing shows

[0023] Fig. 1 shows a schematic view of the tray of an exemplary contact plate from above.

[0024] Fig. 2 shows a schematic view of the bowl from Fig. 1 from below.

[0025] Fig. 3 shows a schematic, cross-sectional view of a container filled with agar.

[0026] The tray of an impression plate in the area between the inner edge and the outer edge,

[0027] Fig. 4 shows a schematic view of the area from Fig. 3, quasi-perspectivally and

[0028] Fig. 5 shows a schematic view of the area from Fig. 4, viewed obliquely from below the shell.

[0029] Fig. 1 shows a top view of the tray 1 of an impression plate, empty. The inner rim 2, which defines the space for filling with agar, is clearly visible. To simplify analysis, a grid 4 is formed in the bottom area 3.

[0030] A slightly lower outer edge 5 is provided. An annular space 6 is defined between the two edges 2, 5. Grooves 7 are formed at or in the base of the annular space 6, which are dimensioned such that they can absorb condensation water by capillary action.

[0031] Fig. 2 shows the bowl 1 from below.

[0032] A lid 8 used for closing is not shown in the figures. Regarding clamping mechanisms and / or mechanisms for aerobic and unaerobic locking, reference is made to the general part of the description to avoid repetition.

[0033] Fig. 3 shows a schematic, cross-sectional view of the annular space 6, in which a total of three grooves 7 are formed for collecting condensation. The grooves 7 can be interconnected by radial transverse grooves (not shown).

[0034] Clamping means 10 extending orthogonally to the base of the annular space 6 are provided towards the inner edge 2, interrupting the inner groove 7. Figure 3 indicates that the dish 1 is filled with nutrient medium 11.

[0035] Fig. 3 further shows the inner edge 2.

[0036] In the annular space 6, the three grooves 7 are visible, which are arranged coaxially to each other and equidistant from each other.

[0037] The outer rim 5 is deeper than the inner rim 2 and extends below the base area 3. The outer rim 5 forms a ring-shaped base for the tray 1.

[0038] Furthermore, Fig. 3 indicates that the area under the grooves 7, which is reduced by the introduction of the grooves 7 into the material, has a material reinforcement 12, so that sufficient stability of the shell 1 in the area of ​​the annular space 6 is ensured.

[0039] Figures 4 and 5 show the area of ​​the annular space 6 according to the representation in Fig. 3, but in a quasi-perspective view according to Fig. 4 from obliquely above and according to Fig. 5 from obliquely below.

[0040] The material reinforcements 12 are integral components and, in the area of ​​the grooves 7 on the underside, are bulged and zonally formed, as is particularly evident in Fig. 5. Between the grooves 7, webs 13 are provided that separate the grooves 7 from one another; these webs are of different thicknesses. The resulting grooves 7 are approximately identical in dimension, although this is not strictly necessary. Regarding further features not covered in the figure description, reference is made to the general section of the description to avoid repetition.

[0041] Finally, it should be expressly pointed out that the embodiment of the impression plate according to the invention described above serves only to discuss the claimed teaching, but does not limit it to the embodiment described above.

[0042] Reference sign list

[0043] 1 bowl

[0044] 2 inner edge

[0045] 3 Floor area

[0046] 4 grids

[0047] 5 outer edge

[0048] 6 annular space

[0049] 7 grooves

[0050] 10 clamping devices

[0051] 11. Nutrient medium

[0052] 12 Material reinforcement

[0053] 13 Bridge

Claims

Claims 1. Contact plate with a dish (1) for receiving a nutrient medium, the dish having a base and an inner rim (2) defining the base, and a lid (8) for aerobic and / or anaerobic closure, the lid being able to be placed over the inner rim (2) by means of a lid rim (9) and optionally locked against the dish (1), wherein the dish (1) has an outer rim (5) extending coaxially at a distance around the inner rim (2), wherein an annular space (6) is formed between the inner rim (2) and the outer rim (5), which serves for inserting and optionally locking the lid rim (9), and wherein at least one groove (7) or radially and / or axially oriented grooves are formed on or in the base of the annular space (6), which serve to receive a liquid, preferably in the form of condensation, flowing over the inner rim (2) and / or the lid (8) into the annular space (6).

2. Contact plate according to claim 1, characterized in that two or three grooves (7) are preferably formed coaxially to each other at or in the base of the annular space (6).

3. Contact plate according to claim 1 or 2, characterized in that the grooves (7) are continuous or interrupted in the circumferential direction.

4. Contact plate according to one of claims 1 to 3, characterized in that the grooves (7) are designed and dimensioned such that their walls or interfaces exert a capillary action on condensation water.

5. Contact plate according to claim 4, characterized in that the grooves (7) have an approximately rectangular cross-section with a groove depth and groove width in the range of 0.3 mm to 0.7 mm, preferably 0.5 mm, or which are semicircular in cross-section.

6. Contact plate according to one of claims 2 to 5, characterized in that the grooves (7) extend so deeply into the bottom of the annular space (6) that the latter is partially or completely reinforced on the downwardly directed outer side.

7. Contact plate according to one of claims 1 to 6, characterized in that the inner edge (2) has an inwardly directed, circumferential step at its upper free end.

8. Contact plate according to one of claims 1 to 7, characterized in that the inner rim (2) comprises, on the inside, retaining means for holding the nutrient medium (11) in the form of ridges, beads, etc.

9. Impression plate according to one of claims 1 to 8, characterized in that a circumferential step, a bead or the like is formed on the inner edge (2), in the area towards the bottom of the tray (1).

10. Contact plate according to one of claims 1 to 9, characterized in that the inner rim (2) has on its outer surface preferably orthogonal to the bottom of the tray thickenings, cams, ridges (13) or the like, which serve to position and / or clamp the lid.

11. Contact plate according to one of claims 1 to 10, characterized in that the outer edge extends from below the upper free end of the inner edge to below the bottom of the tray, so that the outer edge defines an annular base downwards.

12. Contact plate according to one of claims 1 to 11, characterized in that the outer rim (5) has an inner diameter which is larger than the outer diameter of the lid rim (9), so that it fits at least slightly over the lid (8) for stacking several contact plates.

13. Contact plate according to any one of claims 1 to 12, characterized in that the edges (2, 5) taper conically in cross-section towards their free ends.

14. Contact plate according to any one of claims 1 to 13, characterized in that the tray (1) and the lid (8) are injection-molded from plastic.

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