FILTER DEVICE FOR FILTERING INSOLUBLE MATERIAL

Description

[0001] The present invention relates to a filter device for filtering insoluble material.

[0002] Such filter devices are used particularly for preparing coffee and tea. The filter device has a tubular steel body with a multitude of filter openings. A base steel body is welded to this steel body; this base steel body may also have a multitude of filter openings, but is often closed.

[0003] To prepare coffee or tea, the coffee grounds or tea leaves are placed in the filter holder, the filter holder is inserted into an opening of a vessel, such as a coffee pot, teapot, or filter holder, and then boiling water is poured into the filter holder. The boiling water comes into contact with the coffee grounds or tea leaves and extracts the aromatic compounds. After a certain contact time between the water and the coffee grounds or tea leaves, the coffee or tea is ready, and the filter holder can be removed from the coffee pot, teapot, or filter holder, and the coffee or tea can be poured into a cup.

[0004] A special application is the use of so-called filter presses, which are described, for example, in WO 2017 / 080885. In these presses, a filter piston is inserted into the steel body from above and pressed down towards the base. In this application, the base has no filter openings. The steel body also typically lacks filter openings adjacent to the base. As the filter piston is moved towards the base, the coffee grounds or tea leaves collect in the area of ​​the base and therefore cannot, or can only to a negligible extent, come into contact with the water. Furthermore, the coffee grounds or tea leaves do not reach the coffee pot or teapot. The extraction of the coffee grounds or tea leaves is largely stopped by pressing down the filter piston.

[0005] When using a filter plunger, the filter device usually remains in the coffee pot or teapot until it is completely empty. If you want to pour the coffee or tea from the coffee pot or teapot into a cup, there is a risk that the filter device could fall out.

[0006] From WO 2007 / 082391 Al, a filter device is known which has radially outwardly projecting bulges at its upper edge. These bulges are formed by a plastic part attached to an upper steel body, the upper steel body being welded to the steel body. The plastic part is designed such that the bulges exhibit a certain degree of elasticity or flexibility. The upper edge allows the filter device to be clamped to the opening of the coffee pot or teapot to prevent it from falling out when pouring coffee or tea into a cup. Furthermore, the bulges can deform to a greater or lesser extent, allowing the filter device to adapt, within certain limits, to different opening sizes and tolerances, particularly in glass coffee pots or teapots.

[0007] From the above explanations, it follows that the filter device according to WO 2007 / 082391 Al comprises a total of three steel bodies, so that consequently two welds are required to join the three steel bodies together. It should be noted here that when manufacturing the steel body from a flat stock, a weld is also required to transform the flat stock into a cylindrical shape; however, this weld does not serve to join the three steel bodies together.

[0008] To ensure a sufficiently stable connection between the upper steel body and the plastic part, the upper steel body must also be fitted with a flange. This makes the manufacture of the filter device comparatively complex and consequently expensive.

[0009] Furthermore, reference is made to WO 2018 / 194450 A1, which shows a device for preparing tea.

[0010] The object of one embodiment of the present invention is to propose a filter device for filtering insoluble material which is easier to manufacture compared to filter devices known from the prior art.

[0011] This problem is solved by the features specified in claim 1. Advantageous embodiments are the subject of the dependent claims.

[0012] One embodiment of the invention relates to a filter device for filtering insoluble material used in the preparation of beverages, in particular for filtering tea leaves or coffee powder, comprising a steel body with a plurality of filter openings, at least one plastic part made of an injection-moldable plastic, which is injection-molded around the steel body in a connecting section, wherein ∘ at least one recess is arranged in the connecting section which is at least partially filled by the plastic part, or ∘ the steel body forms a projection extending from the steel body in the connecting section which is at least partially enclosed by the plastic part.

[0013] In the proposed filter device, a direct connection between the plastic part and the steel body is possible. The plastic part engages in the recesses and at least partially fills them, or it encloses the extension, creating an undercut and consequently a positive fit between the plastic part and the steel body. For this to occur, the steel body simply needs to be inserted into an injection mold accordingly. In the proposed filter device, the upper steel body is replaced by the plastic part, unlike in WO 2007 / 082391 Al. Therefore, it is no longer necessary to provide an additional weld to connect the upper steel body to the steel body. It is also no longer necessary to equip the upper steel body with a flange. This simplifies manufacturing and thus reduces costs.

[0014] According to the invention, the filter device comprises a further plastic part, wherein the plastic part has at least receiving sections for a further plastic part which is injection molded around the plastic part.

[0015] Adding an extra plastic part allows the filter device to be equipped with additional functions. For example, this extra plastic part can form a loop or similar feature, allowing the filter device to be hung on a hook. This makes it easy to store the filter device, for instance, in a kitchen. The plastic part that is connected to the steel body does not need to be modified for this. Therefore, various versions of the filter device can be provided with relatively simple means.

[0016] According to a further embodiment, the recess can be designed as a through-hole extending completely through the steel body. In this embodiment, the recess can be produced relatively easily and cost-effectively, for example by punching. Furthermore, the size of the undercut is maximized. Consequently, the connection between the plastic part and the steel body is strengthened.

[0017] In a further developed embodiment, The steel body has a first side and a second side, the through-hole runs through the steel body from the first side to the second side, and the plastic part is injection-molded around the steel body on the first side and on the second side, completely filling the through-hole.

[0018] In this embodiment, the plastic part rests against the steel body on both the first and second sides. Furthermore, the plastic part completely passes through the opening. This creates a particularly robust connection between the plastic part and the steel body.

[0019] In a further developed embodiment, The steel body has an upper edge and a lower edge, the upper edge protrudes radially outwards from the rest of the steel body and encloses a filling opening, the connecting section is formed by the upper edge, and the plastic part is arranged at the upper edge.

[0020] In this embodiment, the plastic part can be mounted radially on the outside, making it easily accessible. As mentioned earlier, boiling water is poured into the filter device to bring it into contact with coffee grounds or tea leaves. Consequently, the filter device itself can also heat up. Due to the lower thermal conductivity of the plastic part compared to the steel body, the risk of burns to a user handling the filter device is reduced.

[0021] According to a further developed embodiment, the plastic part comprises a first plastic and a second plastic, wherein the first plastic fills the recess or encloses the extension, and the second plastic at least partially encloses the first plastic. Due to the use of two different plastics, both preferably suitable for injection molding, their properties can be optimally utilized for their respective functions. The first plastic forms the connection between the plastic part and the steel body, so the first plastic should exhibit, in particular, high dimensional stability even under changing temperatures. The second plastic is the one that is handled by a user. Therefore, the second plastic can be selected according to tactile and visual considerations.

[0022] In another embodiment, the first plastic has a lower hardness than the second plastic and / or the second plastic has a lower thermal conductivity than the first plastic. As mentioned, the first plastic forms the connection between the plastic part and the steel body. A harder plastic allows for a particularly durable connection between the plastic part and the steel body. Conversely, a softer plastic offers a more pleasant feel for the user. As mentioned earlier, the filter device is placed on or inserted into a coffee pot or teapot. A softer plastic can conform to the shape of the coffee pot or teapot to some extent in the contact area, thus making unintentional slippage more difficult and increasing operational reliability.

[0023] The lower thermal conductivity of the second plastic ensures that the plastic part where the user grips the filter device heats up only minimally, even when boiling water is poured onto the insoluble material. This significantly reduces the likelihood of the user burning their hands when using the device.

[0024] These conditions are met, for example, when polypropylene (PP) is used as the first plastic and a thermoplastic elastomer (TPE) is used as the second plastic.

[0025] In another embodiment, the upper edge can have an upper rim width and the lower edge a lower rim width, with the upper rim width being larger than the lower rim width. In this embodiment, the steel body can approximately have the shape of a truncated cone or a truncated pyramid. Furthermore, it has been found that the truncated cone or truncated pyramid shape of the steel body prevents or at least slows down the accumulation of water in the filter device.

[0026] A further developed embodiment can be characterized by a base steel body welded to the lower edge of the steel body. To prevent coffee grounds or tea leaves from entering the coffee pot or teapot over the lower edge, it must be ensured that the steel body is closed in the area of ​​the lower edge. For manufacturing reasons, the simplest way to close the steel body is with a base steel body in the area of ​​the lower edge.

[0027] According to a further embodiment, the base steel body can have a bottom wall and at least one side wall, wherein the bottom wall is provided with a plurality of filter openings or the bottom wall encloses a bottom opening which is covered by a base plate with a plurality of filter openings. To optimize the extraction of the coffee grounds or tea leaves, the residence time of the boiling water in the filter device should be neither too short nor too long. Furthermore, waterlogging or even clogging of the steel body should be prevented. It has been found that providing the bottom wall with a plurality of filter openings while simultaneously designing the side wall without filter openings increases the residence time of the boiling water within the filter device without risking waterlogging or clogging of the steel body.A slight increase in brewing time results in a more intense or stronger coffee or tea without making it too bitter. The base steel body can be made in one or two pieces. The base plate can be flat, which simplifies the manufacturing of the filter openings compared to a one-piece design, for example, because the wall thickness of the base plate can be chosen independently of the rest of the base steel body. In particular, the wall thickness of the base plate can be less than that of the rest of the base steel body, which simplifies and speeds up the manufacturing of the filter openings.

[0028] In another embodiment, it may be advantageous that the steel body has a first side and a second side, the through-opening extends through the steel body from the first side to the second side, and the plastic part ∘ is injection-molded around the steel body on the first side, wherein the plastic part is flush with the second side in the area of ​​the through-opening, or ∘ is injection-molded around the steel body on the second side, wherein the plastic part is flush with the first side in the area of ​​the through-opening, or the plastic part ∘ is injection-molded around the steel body on the first side and the extension protrudes beyond the first side, or ∘ is injection-molded around the steel body on the second side and the extension protrudes beyond the second side.

[0029] In this embodiment, the plastic part encloses the steel body on only one side. Furthermore, the plastic part is flush with the side not enclosed by the plastic part in the area of ​​the through-opening. Consequently, the side not enclosed by the plastic part has no indentations or protrusions. This prevents coffee grounds or tea leaves from adhering, thus simplifying the cleaning of the filter device.

[0030] According to a further embodiment, The steel body has an upper rim and a lower rim, the upper rim encloses a filling opening, the connecting section is formed by the upper rim, and the plastic part is arranged at the upper rim.

[0031] Positioning the plastic part at the top edge allows a user to securely grasp the filter device even when it has been heated by boiling water.

[0032] In a further developed embodiment, the plastic part can have a number of openings arranged outside the steel body, and the other plastic part can have the same number of projections arranged adjacent to the openings. The projections can be elastically designed so that the filter device can be inserted into the opening of a coffee pot or teapot, with the projections deforming. This creates a certain amount of friction between the projections and the opening of the coffee pot or teapot, thus preventing the filter device from falling out. Furthermore, the projections can deform to a greater or lesser degree. Therefore, differences in the size of the openings of the coffee pots or teapots can be accommodated.Especially when coffee pots or teapots are made of glass, relatively large tolerance deviations often occur in the area of ​​the insert openings, which can be compensated for by the protrusions. Within certain limits, the filter device according to this embodiment can also be used for different coffee pots or teapots.

[0033] In another embodiment, a closed steel base can be welded to the lower edge of the steel body. As mentioned earlier, the steel body can be closed particularly easily at the lower edge using a steel base. This closure is necessary to prevent coffee grounds or tea leaves from getting into the coffee pot or teapot.

[0034] A further developed embodiment can be characterized in that the plastic part is designed as a handle or forms a handle. Designing the plastic part as a handle facilitates handling of the filter device. Due to the lower thermal conductivity of plastic compared to steel, the risk of a user burning their hands when grasping the filter device is significantly reduced.

[0035] Exemplary embodiments of the invention are explained in more detail below with reference to the accompanying drawings. These show Figure 1A a bottom view of a filter device according to the prior art, Figure 1B the in Figure 1A filter device shown along the in Figure 1A defined section plane AA, Figure 2A a bottom view of a filter device according to the invention in a first embodiment in a first manufacturing state, Figure 2B the in Figure 2Afilter device shown along the in Figure 2A defined section plane BB, Figure 2C a bottom view of the filter device according to the invention in a second manufacturing state, Figure 2D the in Figure 2C filter device shown along the in Figure 2C defined section plane CC, Figure 2E a general and not to scale enlarged representation of the in 2D Figure marked area A, Figure 2Fine underside view of the filter device according to the invention in a third, completed manufacturing state, Figure 2Gthe in Figure 2F filter device shown along the in Figure 2F defined section plane DD, Figure 3A a perspective view of a second embodiment of the filter device according to the invention in a first manufacturing state, Figure 3Legs perspective view of the in Figure 3AThe filter device shown is in a second, completed manufacturing state, Figure 3C, a top view of the filter device shown in Figure 3C. Figure 3B filter device shown, Figure 3. Your cross-sectional view through the in Figure 3B filter device shown along the in Figure 3C defined section plane EE, Figure 3E a general and not to scale enlarged representation of the in 3D figure marked area B, Figure 4A a sectional view through a third embodiment of the filter device in an unfinished manufacturing state, Figure 4Legs enlarged view of the in Figure 4A marked area C, Figure 5A a perspective view of a fourth embodiment of the filter device according to the invention in a first manufacturing state, Figure 5Legs sectional view through the in Figure 5AThe filter device shown, however in its finished manufacturing state, Figure 5C is an enlarged view of the one shown in Figure 5B marked area D, Figure 5. Your enlarged representation of the area shown in Figure 5B marked area E, Figure 5E an enlarged view of the base steel body of the in Figure 5A illustrated filter device, and Figure 5 Fine separate top view of a base plate of the base steel body according to Figure 5E .

[0036] In the Figures 1A and 1B A filter device 10 known from WO 2007 / 082391 A1 is shown in two different views. The filter device 10 has a steel body 12 provided with a plurality of filter openings 14. For the sake of clarity, in Figure 1B Only some of the filter openings 14 are shown. However, the areas which are in Figure 1A which are limited by the filter openings 14, are fully provided with further filter openings 14.

[0037] The steel body 12 is essentially cylindrical and can be manufactured from a flat sheet by bending. Consequently, the filter openings 14 can be punched, etched, or produced by a similar method. Etching is particularly suitable because the steel body has a thin wall (< 1 mm). The steel body 12 has an upper rim 16 and a lower rim 18. A base steel body 20 is welded to the steel body 12 at the lower rim 18. The base steel body 20 has a bottom wall 22, which, however, is not provided with filter openings 14. The base steel body 20 also has a side wall 24, which also does not form filter openings 14. The side wall 24 of the base steel body 20 projects into the steel body 12, and the base steel body 20 is welded to the base steel body 12 at the side wall 24.

[0038] At the upper edge 16, an upper steel body 26 is welded to the steel body 12. The upper steel body 26 forms a filling opening 28 through which coffee grounds, tea leaves, or the like, as well as water, can be filled into the filter device 10. The upper steel body 26 also has a funnel-shaped section 30 and a flange 32 to which a plastic body 33 is attached. The plastic body 33 rests against the upper steel body 12, except for protrusions 34. Therefore, a cavity 35 is formed between the protrusions 34 and the plastic body 33, which is why the plastic body 33 has a higher elasticity in the area of ​​the protrusions 34 than in the rest of the area.

[0039] When the filter device 10 is inserted into the opening of a coffee pot or teapot (not shown), the protrusions 34 deform, creating friction between the opening and the protrusions 34. As a result, the filter device 10 is clamped to the coffee pot or teapot, preventing it from falling out when coffee or tea is poured into a cup. Furthermore, the protrusions 34 can deform to varying degrees, allowing the filter device 10 to adapt, within certain limits, to different sizes of the coffee pot or teapot opening.

[0040] In the Figures 2A and 2B Figure 1 shows a first embodiment of a filter device 36 1 according to the invention in a first manufacturing state. As also shown in the Figures 1A and 1BThe filter device 36 1 shown in the invention comprises a steel body 12 with a plurality of filter openings 14. Again, only some of the filter openings 14 are shown, with the area of ​​the steel body 12 bounded by the filter openings 14 being completely provided with filter openings 14. The steel body 12 has a substantially cylindrical shape with an upper rim 16 having an upper rim width WO and a lower rim 18 having a lower rim width WU, wherein the upper rim width WO corresponds approximately to the lower rim width WU. Therefore, the filter device 36 1 according to the first embodiment is suitable for use in filter presses.

[0041] At the lower edge 18, a base steel body 20 is welded to the steel body 12. The base steel body 20 has a bottom wall 22 which is not provided with filter openings 14.

[0042] Furthermore, the base steel body 20 includes a side wall 24, which also does not form any filter openings 14. The base steel body 20 is welded to the steel body 12 via the side wall 24.

[0043] At the upper edge 16, the steel body 12 forms a connecting section 38 in which a total of four recesses 40 are arranged, which in the illustrated embodiment of the filter device 36 1 are designed as a through-opening 42 with a square cross-section that passes completely through the steel body 12.

[0044] In the Figures 2C and 2D is located in the Figures 2A and 2BThe illustrated filter device 36 1 is shown in a second manufacturing state. At the upper edge 16, a plastic part 44 made of an injection-moldable plastic, for example polypropylene (PP), is injection-molded around the steel body 12 in the connecting section 38. The steel body 12 has a first side 46 and a second side 48, wherein, in the illustrated embodiment, the first side 46 is the outside and the second side 48 is the inside of the steel body 12. The plastic part 44 is injection-molded around the steel body 12 at the first side 46, with the plastic part 44 projecting into the through-opening 42. The plastic part 44 is flush with the second side 48 of the steel body 12, as shown in Figure 2E as shown by means of a basic illustration. Figure 2E shows the in 2D Figure The marked area A is not to scale and is greatly simplified.

[0045] Furthermore, the plastic part 44 forms a receiving section 50, which in the illustrated embodiment comprises a lower radial extension 52 and an upper radial extension 54, wherein the upper radial extension 54 extends further radially outwards than the lower radial extension 52. In addition, the plastic part 44 is equipped with a total of four openings 56, which completely traverse the plastic part 44.

[0046] In the Figures 2F and 2GThe filter device 36 1 is shown in its completed state. A further plastic part 58 is injection-molded around the plastic part 44, with the further plastic part 58 extending upwards from the lower radial extension and completely enclosing the upper radial extension 54. The further plastic part 58 can be made of a thermoplastic elastomer (TPE). The TPE can be selected, for example, based on its hardness. In this case, a TPE with a hardness between 50 and 68 Shore A, particularly 54 Shore A, could be chosen. Alternatively, styrene-acrylonitrile (SAN) could be used. In the area of ​​the upper radial extension 58, the further plastic part 58 forms a support rim 60, which allows the filter device 36 1 to be placed on a coffee pot or teapot.

[0047] In the areas where the openings 56 are located, the additional plastic part 58 has a projection 62 that extends radially outwards. While the additional plastic part 58 rests directly against the plastic part 44 and consequently comes into contact with it radially outwards, this contact is eliminated in the area of ​​the projections 62 and the openings 56. As a result, the additional plastic part 58 exhibits increased elasticity or flexibility in the area of ​​the projections 62 than in the remaining area.

[0048] From this description, it follows that the filter device 36 1 according to the first embodiment comprises the base steel body 20 and the steel body 12, which must be welded together. In contrast to the one described in the Figures 1A and 1BIn the illustrated filter device 10, a steel body and therefore a second weld seam for connecting the steel body 12 to the now-missing steel body are eliminated. The plastic part 44 and the further plastic part 58 can be manufactured using the same injection mold without having to change the position of the steel body 12 in the injection mold. The manufacture of the filter device 36 1 according to the first embodiment is therefore significantly simpler and more cost-effective than the manufacture of the one shown in the Figures 1A and 1B illustrated filter device 10.

[0049] The filter device 36 1 can be inserted into an opening of a coffee pot or teapot (not shown), whereby the projections 62 are deformed to a greater or lesser degree. As a result, friction occurs between the opening and the projections 62, thus securing the filter device 36 1 to the coffee pot or teapot. This prevents the filter device 36 1 from falling out of the coffee pot or teapot.

[0050] The Figures 3A to 3D show a second embodiment of the filter device 36 2 according to the invention. Figure 3A Figure 36 shows the filter device 36 2 in a first manufacturing state. As in the first embodiment, the steel body 12 is provided with a plurality of filter openings 14, which are located in the Figures 3A to 3D only partially and in the Figures 3A to 3DThese figures are shown only in principle. The filter openings 14 can have a diameter of approximately 0.2 mm or larger.

[0051] In this case, the upper edge width WO of the upper edge 16 is larger than the lower edge width WU of the lower edge 18. In the illustrated embodiment, the steel body 12 therefore has a frustoconical shape. A base steel body 20, which also has the shape of a frustocone, is welded to the lower edge 18 of the steel body 12. The base steel body 20 has a bottom wall 22 and a side wall 24, the bottom wall 22 being, for example, Figure 3CIt is evident that the base steel body 20 is equipped with a number of filter openings 14. However, the side wall 24 of the base steel body 20 does not have any filter openings 14. The residence time of the hot water in the filter device 36 1 can be determined by the number and diameter of the filter openings 14. As mentioned, the filter openings 14 have a diameter of approximately 0.2 mm, making them comparatively small. Compared to larger filter openings 14, this reduces the flow rate through the steel body 12, thus increasing the residence time of the hot water. The fact that the side wall 24 of the steel body 12 does not have any filter openings 14 also leads to an increase in the residence time of the hot water. This allows more flavor compounds to be extracted from the coffee grounds or tea leaves without the filter openings 14 becoming blocked.

[0052] The upper rim 16 of the steel body 12 is flange-shaped and extends radially outwards. The upper rim 16 encloses a filling opening 28 through which coffee powder, tea leaves or the like, as well as water, can be filled into the filter device 36 2.

[0053] Referring to the Figure 3A The upper edge 16 forms the connecting section 38, the connecting section 38 having a radially outwardly pointing tongue 64. Two through-openings 42 with a circular diameter are arranged on this tongue 64.

[0054] In the Figures 3B to 3D The filter device 36 2 according to the second embodiment is shown in a second, completed state. It can be seen that the plastic part 44 has been injection-molded around the connecting section 38. The plastic part 44 is designed in the manner of a handle 66, by which the filter device 36 2 can be grasped. Figure 3Edoes not show to scale and purely in principle the 3D figure Defined section B. It can be seen that the steel body 12 has a first side 46 and a second side 48, and the through-opening 42 extends through the steel body 12 from the first side 46 to the second side 48. The plastic part 44 is injection-molded around the steel body 12 on both the first side 46 and the second side 48, with the plastic part 44 completely filling the through-opening 42.

[0055] The in the Figures 4A and 4B The third embodiment of the filter device 36 3 shown largely corresponds to that described in the Figures 2A to 2GThe first embodiment of the filter device 36 1 is shown. Therefore, only the essential differences will be discussed below. Instead of the recesses 40, the steel body 12 forms a radially outwardly projecting extension 68 from the rest of the steel body 12. In the third embodiment of the filter device 36 3, this extension is flange-shaped and is located at the upper edge 16 of the steel body 12. The extension 68 projects beyond the first side 46 of the steel body 12. The extension 68 is enclosed by the plastic part 44, thus creating a reliable connection between the steel body 12 and the plastic part 44.

[0056] The in the Figures 5A to 5F The fourth embodiment of the filter device 36 4 shown largely corresponds to that described in the Figures 3A to 3EThe second embodiment of the filter device 36 2 shown. Therefore, only the essential differences will be discussed below. As can be seen from a comparison of the Figures 3A and 5A As can be seen, the filter device 36 1 according to the fourth embodiment does not have the tongue 64, which in the second embodiment of the filter device 36 2 is enclosed by the plastic part 44 (cf. Figure 3B In this case, the extension 68 is formed by the upper edge 16 and is completely enclosed by the plastic part 44, as shown in the Figure 5B emerges.

[0057] Especially from the Figures 5C and 5DIt is evident that the plastic part 44 comprises a first plastic 70 and a second plastic 72. The first plastic 70 is the one that comes into contact with the steel body 12 and encloses the extension 68. The second plastic 72 is applied to the first plastic 70 and, in the fourth embodiment of the filter device 36 1, has no contact with the steel body 12. A user grasps the filter device 36 1 with the second plastic 72 using the handle 66.

[0058] The first plastic 70 can be polypropylene (PP) and have a higher hardness than the second plastic 72. The second plastic 72 can have a lower thermal conductivity than the first plastic 70. A thermoplastic elastomer (TPE) is particularly suitable as the second plastic 72.

[0059] In Figure 5EThe base steel body 20 of the filter device 36 3 is shown separately. In contrast to the base steel body 20 of the filter device 36 2 according to the second embodiment, the base steel body 20 of the filter device 36 1 according to the fourth embodiment is designed in two parts and forms a bottom opening 74, which is formed by a base plate 76, which is in Figure 5F The base plate 76, shown separately, is covered in its intended state. The base plate 76 has a plurality of filter openings 14, while the remaining steel base body 20 has no filter openings 14. The base plate 76 can, for example, be firmly connected to the steel base body 20 by means of a weld or simply rest on the steel base body 20. In the latter case, the base plate 76 can be removed from the steel base body 20, for example, for cleaning purposes. Reference symbol list

[0060] 10 Filter device 12 Steel body 14 Filter opening 16 Upper edge 18 Lower edge 20 Base steel body 22 Base wall 24 Side wall 26 Upper steel body 28 Filling opening 30 Funnel-shaped section 32 Flange 33 Plastic body 34 Bulge 35 Cavity 36 Filter device 36 1 to 36 4 Filter device 38 Connecting section 40 Recess 42 Passage opening 44 Plastic part 46 First side 48 Second side 50 Receiving section 52 Lower radial extension 54 Upper radial extension 56 Opening 58 Further plastic part 60 Support edge 62 Projection 64 Tongue 66 Handle 68 Extension 70 First plastic 72 Second plastic 74 Bottom opening 76 Base plate WOupper edge width WUlower edge width

Claims

1. Filter device (36) for filtering insoluble material used in the preparation of beverages, in particular for filtering tea leaves or coffee powder, comprising - a steel body (12) with a plurality of filter openings (14), - at least one plastic part (44) made of an injection-moldable plastic, which is injection-molded around the steel body (12) in a connecting section (38) of the steel body (12), wherein ∘ at least one recess (40) is arranged in the connecting section (38), which is at least partially filled by the plastic part (44), or ∘ the steel body (12) forms an extension (68) in the connecting section (38) which protrudes from the steel body (12) and is at least partially surrounded by the plastic part (44), characterized in that the filter device (36) has a further plastic part (58), and the plastic part (44) has at least one receiving section (50) for the further plastic part (58), which is injection-molded around the plastic part (44).

2. Filter device (36) according to claim 1, characterized in that the recess (40) is formed as a passage opening (42) completely passing through the steel body (12).

3. Filter device (36) according to claim 2, characterized in that - the steel body (12) has a first side (46) and a second side (48), - the passage opening (42) passes through the steel body (12) from the first side (46) to the second side (48), and - the plastic part (44) is injection-molded around the steel body (12) at the first side (46) and at the second side (48) and completely fills the passage opening (42).

4. Filter device (36) according to claim 3, characterized in that - the steel body (12) has an upper margin (16) and a smaller margin (18), - the upper margin (16) protrudes radially outward from the remaining steel body (12) and surrounds a filling opening (28), - the connecting section (38) is formed by the upper margin (16), and - the plastic part (44) is arranged at the upper margin (16).

5. Filter device (36) according to claim 4, characterized in that the plastic part (44) - comprises a first plastic (70) and a second plastic (72), wherein - the first plastic (70) fills the recess (40) or surrounds the extension (68) and the second plastic (72) at least partially surrounds the first plastic (70).

6. Filter device (36) according to claim 5, characterized in that - the first plastic (70) has a smaller hardness than the second plastic (72) and / or - the second plastic (72) has a smaller thermal conductivity than the first plastic (70).

7. Filter device (36) according to one of claims 4 to 6, characterized in that - the upper margin (16) has an upper margin width (WO) and the lower margin (18) has a lower margin width (WU), wherein the upper margin width (WO) is greater than the lower margin width (WU).

8. Filter device (36) according to one of claims 4 to 7, characterized in that a bottom steel body (20) is welded to the steel body (12) at the lower margin (18).

9. Filter device (36) according to claim 8, characterized in that the bottom steel body (20) has a bottom wall (22) and at least one side wall (24), wherein - the bottom wall (22) is provided with a plurality of filter openings (14), or the bottom wall (22) surrounds a bottom opening (74) which is covered by a bottom plate (76) having a plurality of filter openings (14).

10. Filter device (36) according to claim 2, characterized in that - the steel body (12) has a first side (46) and a second side (48), - the passage opening (42) passes through the steel body (12) from the first side (46) to the second side (48), and - the plastic part (44) ∘ is injection-molded around the steel body (12) at the first side (46), wherein the plastic part (44) is terminating flush with the second side (48) in the region of the passage opening (42) or ∘ is injection-molded around the steel body (12) at the second side (48), wherein the plastic part (44) is terminating flush with the first side (46) in the region of the passage opening (42), or - the plastic part (44) ∘ is injection-molded around the steel body (12) at the first side (46) and the extension (68) protrudes beyond the first side (46), or ∘ is injection-molded at the second side (48) around the steel body (12) and the extension (68) protrudes beyond the second side (48).

11. Filter device (36) according to claim 10, characterized in that - the steel body (12) has an upper margin (16) and a lower margin (18), - the upper margin (16) surrounds a filling opening (28), - the connecting section (38) is formed by the upper margin (16), and - the plastic part (44) is arranged on the upper margin (16).

12. Filter device (36) according to claim 11, characterized in that - the plastic part (44) has a number of apertures (56) arranged outside the steel body (12), and - the further plastic part (58) has the same number of projections arranged adjacent to the apertures (56).

13. Filter device (36) according to claim 12, characterized in that a closed bottom steel body (20) is welded to the steel body (12) at the lower margin (18).

14. Filter device (36) according to one of the preceding claims, characterized in that the plastic part (44) is formed as a handle piece (66) or forms a handle piece (66).