The invention relates to a filter device for filtering a liquid, wherein the filter device has a container and a filter module which can be detachably connected to the container, wherein the container has an inlet chamber for receiving the liquid to be filtered and an outlet chamber for receiving the filtered liquid, said outlet chamber being connected to the inlet chamber via a connecting portion, wherein the connecting portion has a filter module seat with a flow- through opening for receiving the filter module, and wherein, when arranged as intended in the filter module seat, the filter module closes the flow-through opening so that the liquid poured into the inlet chamber via an inlet opening can flow through the filter module along a filter flow path into the outlet chamber.

A wide variety of filter devices are used for filtering liquids and in particular drinking water. In the context of sensitizing the population, the demand for clean and non-contaminated drinking water increases. Depending on the unhealthy contaminants, such as heavy metals or toxins, potentially present in the drinking water and also other salts dissolved in the drinking water, such as chlorides, nitrates or carbonates, which may, in higher concentrations, influence the taste of the drinking water, different filter modules adapted thereto are used with special filter media. This includes, for example, non-specific filter media, such as activated carbon, with a large adsorbent surface and also membrane filters which are able to filter out unwanted components of the drinking water and to thus retain them from the filtrate.

On the other hand, the use of treated drinking water can, for example, have advantageous effects on coffee machines, kettles or similar devices which are used in the household and must be filled with drinking water in order to function. This is because insufficiently or incorrectly treated water can lead to negative effects, such as calcification of water-conducting household appliances up to machine defects. In addition to the specific and non-specific filter media, the filter media used may also contain ion exchangers which are able to soften calcium-ion- containing water and to replace calcium ions with other ions. In this manner, deposits caused by sparingly soluble calcium salts can inter alia be reduced. Commercially available and common household filter devices with a container, e.g., in the form of a jug or a carafe, are also known from practice. In this case, in a first step, unfiltered drinking water is first poured through a filling opening into an inlet chamber of the container. Due to gravity and in some cases by means of a pump, the drinking water to be filtered usually flows along a filter flow path through the filter module into an outlet chamber arranged under the inlet chamber. In this case, the filter module is arranged in a filter module seat in a connecting portion connecting the inlet chamber to the outlet chamber and thereby closes a passage opening in this connecting portion via which the inlet chamber is connected to the outlet chamber. The filtered drinking water can be stored in the outlet chamber until the intended use. The outlet chamber has an outlet opening through which the drinking water filtered by means of the filter module can be poured into a vessel or a drinking glass.

The filter modules used in this case can be detachably connected to the container almost without exception, so that a used-up filter module can simply be removed from the container and replaced by a new and unconsumed filter module. Advantageously, this replacement of the filter module is possible without complicated disassembly of the filter device.

In order to achieve the above-described advantages of the filtered drinking water, it is essential to use a filter module suitable and intended for the respective use. In the case of any filter module not configured for the respective purpose, the resulting filter effect is not apparent or controllable for the user. An unsuitable filter module cannot or can only insufficiently provide the filter performance, wherein negative effects can occur as a result of the insufficiently filtered drinking water. Furthermore, in the case of filter devices which monitor a total useful life or a total volume of the liquid filtered with a filter module in order to specify a replacement interval, the necessary replacement intervals of the filter module cannot be reliably ascertained or specified to the user by means of an instruction manual when an unsuitable filter module is used. It is therefore of great importance that suitable filter modules are only ever used. The object of the present invention is therefore to provide a filter device for a liquid, the filter device making it possible to detect, and thereby impede, unintentional use of filter modules that are unsuitable for this filter device.

The object is achieved in that the filter module has a blocking element, wherein, when the filter module is arranged as intended in the filter module seat, at least one bypass-flow opening connecting the inlet chamber to the outlet chamber along a bypass path is mechanically closed by means of the blocking element. In this way, it can be achieved that, when an unsuitable filter module is used, the drinking water to be filtered flows at least partially along the bypass path and, circumventing the filter module, through the at least one bypass-flow opening from the inlet chamber into the outlet chamber. The inlet chamber is emptied significantly more quickly, which a user can readily determine quickly. It can thus be indicated visibly to the user that the filter module used is not suitable for use or else is not properly arranged in the filter module seat and the at least one bypass-flow opening is not completely closed. This can reliably prevent the use of unsuitable filter modules, wherein the unsuitable filter module is indicated to the user by the water to be filtered flowing out through the at least one bypassflow opening.

For this purpose, the container with the inlet chamber and the outlet chamber can, for example, have a virtually cylindrical shape or, in each case, an approximately oval base area. Furthermore, the connecting portion connecting the inlet chamber to the outlet chamber can be designed as an insert which forms the inlet chamber and can be inserted into the upper region of the outlet chamber in the container. The filter module seat with the flow-through opening for receiving the filter module can in this case be arranged on a bottom of the insert. When arranged as intended, the filter module closes the flow-through opening. The water to be filtered can be poured through the inlet opening into the inlet chamber, wherein it flows, driven by gravity or additionally pressurized, through the filter module from the inlet chamber into the outlet chamber. Any contaminants can be filtered from the drinking water by the filter media arranged in the filter module. The at least one bypass-flow opening can be arranged on a bottom or on a side wall of the connecting portion designed as an insert. When an unsuitable filter module is used, the drinking water to be filtered flows from the inlet chamber into the outlet chamber not only along the filter flow path through the filter module but also, by circumventing the filter module, along the bypass path through the at least one bypass-flow opening. When a suitable filter module is used, the at least one bypassflow opening and thus the bypass path can be completely blocked by the blocking element of the suitable filter module so that the water to be filtered flows exclusively from the inlet chamber through the filter module into the outlet chamber.

According to an advantageous embodiment of the invention, it is provided that the blocking element is a closing element arranged on the filter module and closes the bypass-flow opening when the filter module is arranged as intended in the filter module seat. In this case, the closing element may be designed as an extension, tongue or tab arranged on the filter module. It is likewise possible for the closing element to be designed elastically in the form of an elastomer so that, when the filter module is arranged as intended in the filter module seat, the closing element can engage in the at least one bypass-flow opening or can be pressed against the bypass-flow opening with an elastic restoring force. In an alternative embodiment, the closing element can rest against and close the at least one bypass-flow opening under a preload. Thus, the at least one bypass-flow opening can be closed in a fluid-tight manner by the closing element of the filter module and the bypass path can thus be blocked so that the water to be filtered flows along the filter flow path through the filter module and can be reliably freed of contaminants and harmful substances there.

Advantageously, it is provided according to the invention that the closing element is rigidly fixed or formed on the filter module. In addition to an embodiment of the closing element as an elastically deformable extension, tongue or tab, the closing element can also be arranged or formed rigidly on the filter module. Various shapes, such as a tongue or tab or a step, for the closing element are conceivable in this respect. When the filter module is arranged as intended in the filter module seat, the closing element preferably rests against the at least one bypass-flow opening such that the latter is closed in a fluid-tight manner and the bypass path is blocked. Furthermore, the closing element may also be formed in one piece with the filter module, wherein the complexity of the production of the filter module can thereby be reduced.

It is also possible and optionally provided according to the invention for the filter device to have a closing device, wherein, when the filter module is arranged as intended in the filter module seat, the blocking element of the filter module is operatively connected with the closing device and actuates a closing element of the closing device so that the at least one bypass-flow opening is closed by the closing element of the closing device. The closing element can be designed as a mechanical rocker or as a lever mechanism, wherein, when the filter module is arranged as intended in the filter module seat, the blocking element of the suitable filter module mechanically actuates the closing element of the closing device so that the closing element closes the at least one bypass-flow opening.

It is preferably provided that the closing element and/or the closing device and/or the at least one bypass-flow opening have a sealing element so that the at least one bypass-flow opening is sealed in a fluid-tight manner when the filter module is arranged as intended in the filter module seat. For an effective filter effect, it is advantageous if the at least one bypass-flow opening is reliably sealed when the suitable filter module is arranged as intended, so that no unfiltered drinking water enters the outlet chamber by circumventing the filter flow path and thus circumventing the filter module itself. Rather, it is to be ensured that the drinking water located in the outlet chamber is completely filtered. For this purpose, the closing element and/or the closing device and/or the at least one bypass-flow opening may have a sealing element made of a deformable elastomer, such as rubber. Preferably, the closing element and the at least one bypass-flow opening may have a sealing element in order to enable the most fluid- tight closure possible. Furthermore, such sealing elements can also compensate for any manufacturing tolerances of the closing element and/or of the at least one bypass-flow opening. The filter module and/or the filter module seat may additionally also have a sealing element in order to additionally be able to arrange the filter module in a fluid-tight manner in the module filter seat. A flow from the inlet chamber into the outlet chamber through the flow-through opening by circumventing the filter module can thus be reliably prevented.

Furthermore, it is possible and optionally provided according to the invention for the at least one bypass path to run in a parallel direction to the filter flow path. In particular in the case of a filter device driven by gravity, wherein the drinking water flows, driven substantially by gravity, from the inlet chamber through the filter module into the outlet chamber, it may be advantageous for the filter flow path to run substantially parallel to the vertical direction of the gravitational field of the Earth in order to enable simple and fast filtration. Furthermore, the bypass path may likewise run substantially parallel to the filter flow path.

According to an advantageous embodiment of the inventive idea, it is provided that an orientation of the filter module relative to the filter seat is predetermined by a form-fitting engagement of the closing element of the filter module with the at least one bypass-flow opening. In this manner, the intended arrangement of the filter module in the filter module seat can be visually detected and checked by the user of the filter device by the filter module being able to, for example, latch detectably into and be fixed in the filter module seat. Thus, the relative arrangement of the filter module can also be maintained during use or during the filling of the filter device. Due to the predetermined and correct seat of the filter module, effective and safe filtration of the drinking water can be assumed at any time.

For this purpose, the filter module can have one or more closing elements which protrude at an angle from a filter module housing and are formed as extensions, which engage in and close the at least one bypass-flow opening when the suitable filter module is arranged. Further advantageous embodiments of the filter device for a liquid are explained with reference to exemplary embodiments illustrated in the drawing. In the drawings:

Figure 1 shows a schematic sectional view of the filter device according to the invention for filtering a liquid with a blocking element,

Figure 2 shows an alternative embodiment of the filter device with a closing element formed rigidly on the filter module, and

Figure 3 shows a further alternative embodiment of the filter device with a plurality of closing elements arranged on the filter module.

Figure 1 shows a schematic sectional view of an embodiment according to the invention of a filter device 1 . The filter device 1 has a container 2 and a filter module 3 that can be detachably connected to the container 2. The container 2 itself has an approximately cylindrical shape with an inlet chamber 4 and an outlet chamber 5 arranged thereabove. The container 2 can be placed on a substrate via a bottom of the outlet chamber 5. The inlet chamber 4 is connected to the outlet chamber 5 via a connecting portion 6, wherein the connecting portion 6 is designed as an insert that forms the inlet chamber 4. Furthermore, on a bottom of the connecting portion 6, the connecting portion 6 has a filter module seat 7 for detachably receiving the filter module 3, and a flow-through opening. When the suitable filter module 3 is arranged as intended in the filter module seat 7, the flow-through opening is closed by the filter module 3 so that a liquid, such as drinking water, which was poured into the inlet chamber 4, can flow only through the filter module 3 into the outlet chamber 5 when a suitable filter module 3 is used and arranged as intended in the filter module seat 7.

Drinking water poured into the inlet chamber 4 via an inlet opening 8 can flow along a thus predetermined filter flow path through the filter module 3 from the inlet chamber 4 into the outlet chamber 5, wherein contaminants are filtered from it by the filter module 3. Arranged on a side wall of the connecting portion 6 designed as an insert is a bypass-flow opening 9 which penetrates the side wall and through which drinking water can flow from the inlet chamber 4 into the outlet chamber 5 when a filter module 3 is not used or when an unsuitable filter module 3 is used. In this manner, the use of the unsuitable filter module 3 is indicated to the user by the drinking water flowing visibly along the bypass path through the bypass-flow opening 9 from the inlet chamber 4 into the outlet chamber 5, circumventing the filter module 3. However, when a suitable filter module is used, the bypass-flow opening 9 is blocked by means of a blocking element 10 of the filter module 3 and by means of a closing device 11 so that the bypass path is blocked and the drinking water can flow exclusively through the filter module 3 into the outlet chamber 5 and is filtered in the process.

The closing device 11 is designed as a rocker, fixed to the connecting portion 6, with a closing element 12. When the suitable filter module 3 is arranged as intended in the filter module seat 7, a formation designed as a blocking element 10 of the filter module 3 projects through the flow-through opening 9 into the outlet chamber 5. In this case, the blocking element 10 presses onto the closing device 11 designed as a rocker, wherein the closing element 12 of the closing device 11 is pressed against or into the bypass-flow opening 9 and seals the bypass-flow opening 9 in a fluid-tight manner so that the bypass path is blocked.

Figure 2 shows an alternative embodiment of the filter device 1 with a closing element 12 which is rigidly formed on the filter module 3. For better clarity, only the connecting portion 6 and the filter module 3 with the flow-through opening 13 are shown here. In this case, the closing element 12 is designed as an extension protruding at an angle from a housing of the filter module 3. When the suitable filter module 3 is arranged as intended in the filter module seat 7, the closing element 12 rests against and closes the bypass-flow opening 9, as a result of which the bypass path is blocked.

Figure 3 shows an embodiment of the filter device 1 , wherein three bypass-flow openings 9 are arranged on the connecting portion 6. For this purpose, the filter module 3 likewise has 3 closing elements 12, which protrude at an angle and are spaced apart from one another on the housing of the filter module 3 and the shape of which are each adapted to the bypass-flow openings 9. When the filter module 3 is arranged as intended in the filter module seat 7, the closing elements 12 each engage in the bypass-flow openings 9 and close the latter in a fluid-tight manner. In this manner, the arrangement of the filter module 3 relative to the filter module seat 7 can be predetermined.

List of reference signs

1 Filter device

2 Container

3 Filter module 4 Inlet chamber

5 Outlet chamber

6 Connecting portion

7 Filter module seat

8 Inlet opening 9 Bypass-flow opening

10 Blocking element

11 Closing device

12 Closing element

13 Flow-through opening