Filter candle and system with a filter candle for water treatment

Description

Field of invention

[0001] The invention relates to a filter cartridge for water treatment, which is filled with an ion exchange material.

[0002] The invention further relates to a water treatment system comprising a filter candle with a filter candle head. Background of the invention

[0003] Water treatment systems that include a filter cartridge are well-known in practice. In particular, BWT AG markets a water treatment system under the brand name "Bestmax®". This system comprises a filter head that can be connected to an existing water line.

[0004] A filter cartridge filled with an ion exchange material is connected to the filter head via a screw connection, whereby water is then passed through the filter cartridge and softened in the process.

[0005] In addition to softening, such filter cartridges can also be used to purify the water and may, for example, contain activated carbon to remove germs.

[0006] The treated water is used particularly in households and catering establishments for operating coffee machines and vending machines for the production of hot and / or cold drinks.

[0007] Softer water can also improve the taste of coffee.

[0008] The system described above can include a filter cartridge with a bypass, within which only a portion of the water is passed through the ion exchange material. The desired degree of softening can be set via an adjustable bypass flow that does not pass through the ion exchange material. In particular, this allows the system to be adapted to varying water hardness levels depending on the location.

[0009] For beverage preparation, the water hardness is typically adjusted to soft to medium-hard. Near-complete softening of the water, especially a total hardness of less than 0.5 °dH, is undesirable. In particular, such extensive softening removes salts from the water, making it, like demineralized water, less suitable for drinking.

[0010] While soft to medium-hard water is ideal for preparing hot drinks, for other kitchen appliances, such as steam cookers, it is best to use water that is as soft as possible, especially almost completely demineralized water, in order to prevent salt and limescale deposits.

[0011] Theoretically, it would be possible to adjust the bypass setting depending on the type of water required, for example, closing it completely when water is needed for a steamer. However, this is cumbersome, especially since filter cartridges are often installed under the counter.

[0012] Furthermore, each time the water is changed, the water behind the filter cartridge in the pipe would have to be drained before water with the changed hardness level could emerge. Relevant background information on this topic can be found under WO 2019 / 038621 A1 and US 2003 / 196948 A1. Object of the invention

[0013] In contrast, the invention is based on the objective of at least reducing the aforementioned disadvantages of the prior art.

[0014] In particular, an object of the invention is to provide a filter candle and a water treatment system in which water with at least two different degrees of hardness can be easily supplied and withdrawn. Summary of the invention

[0015] The object of the invention is already solved by a filter candle for water treatment by a system for water treatment with a filter candle according to one of the independent claims.

[0016] Preferred embodiments and further developments of the invention can be found in the subject matter of the dependent claims, the description and the figures.

[0017] The invention relates to a filter cartridge for water treatment, which is designed to be connected to a filter head.

[0018] In particular, the invention relates to a filter candle with a connection head which, for example, includes a screw thread for coupling to the filter head.

[0019] The filter head is designed for on-site connection to the water pipe.

[0020] This way, when the ion exchange material is used up, the filter cartridge can be easily removed and replaced with a new one.

[0021] The filter cartridge includes a housing filled with an ion exchange material for softening the water to be treated.

[0022] The ion exchange material can be in granular form, for example as an ion exchange resin. This is loaded with hydrogen, which is exchanged for alkali and alkaline earth ions in the water.

[0023] The filter candle comprises a head with one inlet and at least two outlets.

[0024] The water to be treated is fed into the filter candle via the inlet.

[0025] When water is drawn at a point of use, the treated water can be discharged via the outlets.

[0026] According to the invention, water that is almost completely softened can be introduced into the filter head at a first outlet of the filter candle, and water that has undergone another treatment step, e.g. by activated carbon, can be introduced into the filter head at the second outlet of the filter candle.

[0027] The filter cartridge therefore includes two outlets, whereby the water within the filter cartridge is treated differently in order to have a different degree of hardness at the two outlets.

[0028] The filter cartridge is designed so that water can be drawn for use from both outlets. The incoming water is therefore treated via both filter stages. When passing through at least one filter stage, the incoming water is softened. When passing through the other filter stage, the incoming water is either softened to a lesser extent than when passing through the first stage, or it is not softened at all, but simply undergoes a different water treatment process.

[0029] According to one embodiment of the invention, this is achieved by the filter candle comprising a bypass through which water which has passed through the ion exchange material can be mixed with water which has not passed through the ion exchange material or has passed through it with a shorter residence time or over a shorter distance of the ion exchange material.

[0030] It is specifically intended that water can be discharged at the second outlet, which has been mixed with the water exiting from the bypass.

[0031] Preferably, this bypass is adjustable via an actuating element, so that the hardness of the water discharged at the second bypass can be adjusted.

[0032] The water exiting the first outlet is preferably not mixed with water from the bypass. This allows water to be supplied at the first outlet that, due to the design of the filter cartridge, has been softened to the maximum extent possible and, in particular, contains so few salts and minerals, similar to demineralized water, that the formation of deposits in appliances where the water is evaporated, such as a steam cooker, is largely prevented. The filter cartridge is specifically designed so that, under normal use, the hardness is below 1 °dH, preferably below 0.5 °dH.

[0033] In one embodiment of the invention, the inlet and the second outlet are arranged coaxially at the head of the filter candle.

[0034] However, it is also possible that the inlet and the second outlet are located on the same head on one side of the filter candle.

[0035] According to one embodiment of the invention, the first outlet (containing the softened water to the maximum possible degree) is rotatably arranged on top of the filter head.

[0036] In particular, the first outlet is designed as a coaxial tube exiting the top of the filter head, which is angled to the side.

[0037] The pipe is preferably rotatable by at least 180°, particularly preferably by 360°, about the central axis of the filter head.

[0038] This allows the first outlet to be easily rotated towards the extraction point.

[0039] In one embodiment, a central inlet or outlet is provided on a central axis of the filter candle, which is surrounded by two coaxial ring channels through which water can either be introduced or discharged.

[0040] In particular, it is planned that the entrance will be located between the first and the second exit.

[0041] The first outlet can, for example, be designed as a central pipe, to which the inlet is radially connected as a ring channel, and the second outlet is connected to the inlet as another ring channel.

[0042] It has been found that this allows both the filter cartridge and the filter head to be designed in a particularly compact manner.

[0043] In a further development of the invention, the filter candle comprises a mixing chamber in which water passed through the ion exchange material is mixed with the bypass current.

[0044] The mixing chamber is therefore intended to provide the water for the second outlet.

[0045] According to a further development of the invention, a backflow preventer is arranged between the ion exchange material present in the filter candle and the mixing chamber.

[0046] The backflow preventer prevents bypass water from entering the water stream leading to the first outlet.

[0047] This ensures that only water that has passed completely through the ion exchange material reaches the first outlet.

[0048] The backflow preventer can extend in a ring shape around a centrally arranged pipe, in particular a downpipe.

[0049] Furthermore, several backflow preventers can be distributed around the centrally located pipe.

[0050] For example, the backflow preventer can be plate-shaped and include at least one lid which can only be opened by water flowing through in one direction and thus acts as a backflow preventer.

[0051] At least one of the lids can be spring-mounted and / or made of springy material.

[0052] Preferably at least one filter layer is arranged between the backflow preventer and the ion exchange material, which retains the ion exchange material.

[0053] The water in the bypass preferably passes through a filter layer.

[0054] It is specifically intended that the water from the aforementioned mixing chamber passes through a filter layer. This filter layer may, in particular, include materials for removing germs and pollutants. Specifically, the filter layer may include activated carbon.

[0055] Providing the bypass within the filter cartridge has the advantage that the water routed through the bypass can also pass through a filter layer of the cartridge. This would not be possible if the bypass were provided via the filter head.

[0056] The invention further relates to a system for treating water with a filter cartridge.

[0057] In particular, the invention relates to a system with a filter cartridge as described above.

[0058] The system includes a filter head into which the filter cartridge is inserted.

[0059] As stated above, the filter cartridge is filled with an ion exchange material.

[0060] The filter head includes one input and at least two outputs.

[0061] According to the invention, the system is designed such that the water that can be drawn from a first outlet is softened more than the water that can be drawn from a second outlet.

[0062] The invention therefore provides to divide the water passed through the filter candle, for example, into two partial streams, which, due to a different residence time in the ion exchange material and / or due to a different treatment, lead to two differently softened types of water.

[0063] Preferably, the water provided at the second outlet is generated via a bypass, through which softened water is mixed with bypass water.

[0064] The bypass can be located inside the filter cartridge, as described above.

[0065] According to another embodiment of the invention, the bypass can also be arranged in the filter head.

[0066] This embodiment of the invention has the advantage that the filter cartridge can be designed more simply. In particular, the filter cartridge only requires one inlet and one outlet.

[0067] However, a disadvantage of this embodiment of the invention is that the water passed through the bypass cannot be treated by media present within the filter candle.

[0068] For the aforementioned first embodiment of the invention, the filter head can have an actuating element with which an actuating element engaging in the filter candle can be operated, via which the flow ratio between main flow and bypass flow can be adjusted.

[0069] In particular, it is intended to provide an actuator which can be moved axially via a rotatable actuating element and which can thus open and close one or more openings of a channel of the filter candle in order to regulate the strength of the bypass current.

[0070] The disclosure further relates to a filter head which is designed for the system described above and which accordingly comprises one inlet and two outlets.

[0071] Otherwise, the filter head can include all the features described above in connection with the filter head.

[0072] In particular, the filter head can include an adjusting element for adjusting the flow ratio between a main and a bypass flow, wherein the adjusting element extends around an outlet brought out centrally through the adjusting element.

[0073] In this embodiment, it is therefore provided that an outlet, in particular the first outlet, through which water can be discharged which is not mixed with water of the bypass flow, is arranged centrally and preferably rotatably to the other connections.

[0074] To make the filter head compact and simple, this outlet is led out of the top of the filter head and is surrounded by the adjusting element, which can be designed in particular as a rotatable ring.

[0075] In another embodiment, a bypass is located in the filter head. Water flowing from the filter cartridge is mixed with incoming water via the bypass. This water, which is therefore less softened, is fed to the second outlet, while water to which relatively little or no incoming water has been added is directed to the first outlet.

[0076] In this embodiment, a filter cartridge with two outlets is not required. However, the water flowing through the bypass is not treated at all. This embodiment is therefore particularly suitable for areas where the incoming water is already perfectly safe for human consumption.

[0077] The revelation also concerns a filter head.

[0078] In particular, the disclosure relates to a filter head with one or more of the features described above.

[0079] The filter head may, but does not necessarily have to, have two outputs. It may also have only one output. A filter cartridge with at least one inlet and at least one output can be inserted into the filter head, in particular by screwing it in.

[0080] The filter head includes an output arranged coaxially to a central axis, which is rotatable.

[0081] The central axis is defined in particular by the central axis of a thread for screwing in the filter cartridge.

[0082] The outlet is designed as an angled, rotatable pipe. This allows the outlet to be easily rotated towards the point of use.

[0083] During further training, an actuator for a bypass extends around the exit.

[0084] A channel for an output is therefore routed through the actuator.

[0085] The adjusting element can be designed to be rotatable, in particular for setting a degree of softening.

[0086] This allows for the provision of a compact filter head that is easy and convenient to connect. Brief description of the drawings

[0087] The subject matter of the invention will below be described with reference to an exemplary embodiment shown in the drawings. Figs. 1 to 13 will be explained in more detail. Fig. 1Figure 1 shows an embodiment of a system according to the invention for the treatment of water, which comprises a filter candle connected to a filter head. Fig. 2 The system displays this in a side view. Fig. 3 is a sectional view along line AA according to Fig. 2 . Fig. 4 is a detailed view of area A of the Fig. 3 . Fig. 5 This is another side view of the system. Fig. 6 is a sectional view along line BB of the Fig. 5 . Fig. 7 is a detailed view of area B of the Fig. 6 . Fig. 8 This is a top view of the filter candle. Fig. 9 This is a top view of the filter head from below. Fig. 10 and Fig. 11 These are longitudinal sections of the filter cartridge. Fig. 12 is an axial section of the filter head and Fig. 13 a cross-section in the area of ​​the entrance. Detailed description of the drawings

[0088] Fig. 1shows a perspective view of a water treatment system 1.

[0089] System 1 comprises a filter cartridge 100, which is inserted into a filter head 200.

[0090] The filter head 200 serves for on-site connection of system 1 and includes an inlet 201 for connection to an on-site water pipe as well as two outlets 202, 203, through which water can be drawn.

[0091] In this view, the outputs 202 and 203 are arranged on the opposite side of the input 201, with output 202 being rotatable by 360° to be aligned towards the point of withdrawal.

[0092] The output 202 is led out of the top of the filter head 200 and is then angled.

[0093] In this embodiment, the first outlet 202 serves to draw water which, as is maximally possible with the filter candle 100, is softened and can thus be used like fully demineralized water, especially for steam-generating devices such as steam cookers.

[0094] Partially softened water can be drawn from the second outlet 203, which can be used in particular for the preparation of drinks.

[0095] For example, the second output 203 can be connected to a machine for preparing hot beverages, such as a fully automatic coffee machine.

[0096] Thus, either softened water can be drawn from the first outlet 202 or partially softened water from the second outlet 203, or water can be drawn from both outlets 202 and 203 simultaneously.

[0097] The desired hardness of the water discharged at outlet 203 can be set via an adjusting device 204.

[0098] The adjusting element 204 is released by pressing the locking element 205 and can then be rotated to adjust the desired degree of hardness.

[0099] In particular, the water softening process is adjusted to the water hardness level at the respective location. Normally, the setting is then not changed again.

[0100] A backflow preventer 215, installed in the line of the first outlet 202, prevents softened water from flowing back. The second outlet also includes a backflow preventer (see Fig. 7 , 211).

[0101] Fig. 2 is a side view of system 1 in the top view of outlets 202 and 203.

[0102] Fig. 3 is a sectional view along line AA of the Fig. 2 .

[0103] The filter cartridge 100 comprises a housing 101. The head 102 of the filter cartridge 100 comprises a thread 103, via which the filter cartridge is connected to the filter head 200.

[0104] The housing provides an interior space 105 which is at least partially filled with a softening material, in particular with a weakly acidic ion exchange resin (not shown).

[0105] Water to be treated is directed from the filter head 200 into the housing 101 via a downpipe 104 and enters the interior 105 at the bottom of the housing via a lower inlet 108, which may include a filter layer.

[0106] The water then passes through the ion exchange material and is discharged, as described in detail below.

[0107] Fig. 4 is a detailed representation of area A of the Fig. 3 , i.e., the area of ​​the head 102 of the filter candle 100 and the filter head 200.

[0108] The filter candle 100 is screwed to the thread 206 of the filter head 200 via the thread 103.

[0109] The filter candle 100 includes an inlet 107, through which water to be treated is introduced into the filter candle 100.

[0110] The flow of the introduced water is shown with arrows on the right and that of the discharged water with arrows on the left.

[0111] The inlet 107 is formed by the downpipe 104, through which water from the filter head 200 flows into the filter candle 100.

[0112] The central channel 120 serves to discharge the water to outlet 202.

[0113] The inlet water is introduced into the downpipe 104 via the channel 121, which is designed as a ring channel, from where it is directed downwards and thus passes through the ion exchange material.

[0114] The central channel 120, which is formed within the filter candle 100 by a pipe 106, is located inside the downpipe 104. Between the pipe 106 and the downpipe 104 is a ring channel through which water can flow downwards.

[0115] The filter candle 100 includes a bypass, which is designed as at least one opening 109 of the downpipe 104.

[0116] Through the opening 109, some of the water from the downpipe 104 can escape at the edge and is introduced via the channel 110 into a mixing chamber 113, which is partially filled with at least one filter layer 112.

[0117] The bypass 109 is adjustable by axially displacing the actuator 207 via the actuating element 204 using a threaded spindle.

[0118] Channel 120, which leads to the second output 202, also passes through actuator 207.

[0119] By raising and lowering the actuator 207, the open cross-section of the opening 109 can be changed so that it forms an adjustable bypass.

[0120] It is understood that instead of one opening 109, there may also be several openings which are opened or closed one after the other.

[0121] From opening 109, the bypass water flows via the ring channel 110 and exits via channel outlet 111, where it mixes with the water flowing from the filter candle 100.

[0122] The water flowing from entrance 201 via inlet 107 is directed through downpipe 104 into the interior 105, where it rises again and passes through the ion exchange material.

[0123] The rising water mixes with the bypass water in mixing chamber 113.

[0124] Water is discharged via channel 114, which leads to the second outlet 203 of the filter head 200. Channel 114 is designed as a ring channel and extends around the downpipe 104.

[0125] The filter candle 100 therefore has an inlet 107, which transitions into a ring channel between the pipe 106 and the downpipe 104, and an outlet also designed as a ring channel 114, which extends around the downpipe 104 and which, in the connected state, leads to the second outlet 203 of the filter head 200.

[0126] The central axial channel 120 forms the outlet of the filter candle 100 and leads to the first outlet 202 of the filter head 200.

[0127] The water flowing through channel 120 is not mixed with the bypass flow, but enters channel 120 via inlet 119 after passing through the ion exchange material.

[0128] To prevent a flow of bypass water to channel 120, a backflow preventer 115 is arranged between the mixing chamber 113 and the inlet 119.

[0129] In this embodiment, the backflow preventer 115 is designed as an annular plate 116 extending through the housing.

[0130] The plate 116 is provided with one or more spring-loaded covers 117.

[0131] In particular, a single ring-shaped cover 117 or several covers 117 distributed around the circumference can be used to close the openings of the plate 116.

[0132] The lid(s) 117 are designed to be flexible and / or spring-mounted and can move away from the oncoming water flowing into the mixing chamber 113.

[0133] If, on the other hand, water is drawn from the first outlet 202, the cover(s) 117 sit on the plate 116, which prevents water from the mixing chamber 113 and thus bypass water from entering the inlet 119.

[0134] In this embodiment, at least one filter layer 118 is arranged between the backflow preventer 115 and the ion exchange material. This layer retains the ion exchange material, which is in the form of granules.

[0135] Fig. 5 This is another side view of the system 1 for water treatment, consisting of filter candle 100 and filter head 200.

[0136] Fig. 6 is a sectional view along line BB of the Fig. 5 .

[0137] Fig. 7 is a detailed view of area B of the Fig. 6 .

[0138] In this view, the section runs along the pipes that form the inlet 201 and the two outlets 202, 203.

[0139] A backflow preventer 210 is arranged on the flow side behind the inlet 201.

[0140] Likewise, a backflow preventer 211 is located in front of the outlet 203.

[0141] In this view it can be seen that below the backflow preventer 115 of the filter candle, water can flow into the channel 120 via the inlet 119, which then passes through the channel 120, which leads through the seal 208 and the actuator 207, to the outlet 202.

[0142] The seal 208, when connected, engages in the pipe 106 and thus connects the central outlet of the filter candle 100 with the outlet 202 of the filter head 200.

[0143] As described above, this water is not mixed with bypass water and can therefore be used particularly for steam-generating devices.

[0144] The incoming water, on the other hand, flows through the ring channel 121 along the downpipe 104. This ring channel 121 extends to the inlet 119 into the channel 120, which leads laterally out of the downpipe 104. Beyond this point, only the downpipe 104 continues downwards.

[0145] The seal 209, through which the channel 120 also passes, seals the inlet 107 to the outside.

[0146] Fig. 8 This is a top view of the Filter Candle 100.

[0147] In the middle is the channel 120, which is formed inside the filter candle 100 by the pipe 122 and which forms the first outlet of the filter candle 100.

[0148] In the connected state, the pipe 122 engages, particularly as shown in the top view of the filter head 200 according to Fig. 9 Seal 208, visible on its underside, through which the channel 120 transitions into the filter head 200.

[0149] The annular channel 121 extends around the pipe 122 and is formed by the downpipe 104.

[0150] The downpipe 104 extends further upwards than the inner pipe 122. Thus, the bypass 109 can be arranged above the inner pipe 122 in the downpipe 104.

[0151] The annular channel 114 extends around the downpipe 104 and is formed by the outer pipe 123, which also extends around the downpipe. This annular channel 114 serves as the second outlet of the filter candle 100.

[0152] The filter head 200 is designed in a complementary fashion and includes an inner ring channel 212, through which water flows into the downpipe 104 and an outer ring channel 213, through which water flows to the second outlet 203.

[0153] Fig. 10 This is an axial sectional view of the head 102 of the filter candle 100.

[0154] The pipe 122 is located further inside the downpipe 104 at a distance, so that the actuator 207 of the filter head 200 can engage in the downpipe in the upper area of ​​the downpipe 104.

[0155] The ring channel 114 of the second outlet extends around the downpipe 104.

[0156] Fig. 11 a sectional view in which opposite Fig. 10 the cutting plane is offset parallel to itself.

[0157] It can be seen that the downpipe 104 is at least partially double-walled. A gap is formed between the inner wall 104a and the outer wall 104b, which contains a channel 110 (see Fig. 4 ) forms, through which bypass water from the opening 109 of the inner wall 104a can flow into the mixing chamber 113.

[0158] The cross-section of the opening 109 can be changed via the actuator 207.

[0159] Fig. 12 is axial section and Fig. 13a cross-section of the filter head 200 in the area of ​​input 201 and second output 203.

[0160] The inlet 201 leads into a receptacle 214 for the downpipe 104, which includes the inlet 107 of the filter candle 100.

[0161] As in Fig. 13 shown for the outer channel 203 of the head 200 to the second outlet 203.

[0162] The invention made it possible to provide a compact water treatment system in which, in addition to an outlet where water is provided, especially for beverages, there is another outlet where more softened water can be drawn, which is used, for example, for steam generation equipment. Reference symbol list

[0163] 1 Water treatment system 100 Filter cartridge 101 Housing 102 Head 103 Thread 104 Downpipe 104a Inner wall of downpipe 104b Outer wall of downpipe 105 Interior 106 Pipe 107 Filter cartridge inlet 108 Lower inlet 109 Opening / Bypass 110 Channel / Annular channel 111 Channel outlet 112 Filter layer 113 Mixing chamber 114 Channel / Annular channel 115 Backflow preventer 116 Plate 117 Cover 118 Filter layer 119 Inlet 120 Channel 121 Channel / Annular channel 122 Pipe 123 Outer pipe 200 Filter head 201 Inlet 202 First outlet 203 Second outlet 204 Actuator 205 Safety device 206 Thread 207 Actuator 208 Seal 209 Seal 210 Backflow preventer inlet 211 Backflow preventer second outlet 212 Annular channel 213 Annular channel / Channel 214 Receptacle 215 Backflow preventer first outlet

Claims

1. A filter candle for treating water, adapted for being connected to a filter head, comprising a housing that is filled with an ion exchange material for softening the water to be treated, wherein the filter candle has a head with one inlet and at least two outlets, wherein water that can be introduced into the filter head at a first outlet is more softened than water that can be introduced into the filter head at a second outlet.

2. The filter candle of the preceding claim, wherein the filter candle comprises a bypass which allows to mix water that has passed through the ion exchange material with water that was not passed through the ion exchange material or was passed therethrough with a shorter dwell time.

3. The filter candle as claimed in any of the preceding claims, wherein the water at the second outlet is has not been softened, but was in particular passed through an activated carbon filter layer of the filter candle.

4. The filter candle as claimed in any of claims 2 or 3, wherein the bypass can be adjusted by means of a control element on the filter head.

5. The filter candle as claimed in any of the preceding claims, wherein the inlet and the outlets at the head of the filter candle are arranged coaxially.

6. The filter candle of the preceding claim, wherein the inlet is arranged between the first and the second outlet.

7. The filter candle as claimed in any of the claims 2 - 6, wherein one or more backflow preventer(s) is / are arranged between a mixing chamber, where water that passed through the ion exchange material is mixed with the bypass flow, and the ion exchange material.

8. The filter candle as claimed in any of the claims 2 - 6, wherein the bypass water passes through a filter layer.

9. A system for water treatment, comprising a filter candle as claimed in any of the preceding claims, and a filter head in which the filter candle is installed, wherein the filter candle is filled with an ion exchange material and wherein the filter head has one inlet and at least two outlets, wherein the system is designed such that the water that can be extracted at a first outlet is softened to a greater extent than the water that can be extracted at a second outlet.

10. The system of the preceding claim, wherein the system comprises a bypass which allows water that has passed through the ion exchange material to be mix with water that was not passed through the ion exchange material or was passed therethrough with a shorter dwell time.

11. The system as claimed in any of the preceding claims, wherein the water of the first and second outlets is passed through a filter layer of the filter candle, in particular through an activated carbon filter layer.

12. The system of the preceding claim, wherein the bypass is located in the filter head and / or in the filter candle.

13. The system of the preceding claim, wherein the filter head comprises a control element which is operable to actuate an actuator which engages in the filter candle and through which the flow ratio between the main flow and the bypass flow can be adjusted.

14. The system as claimed in any of the preceding claims, wherein one outlet, in particular the first outlet, is aligned coaxially to a central axis of the filter head and / or is arranged so that it can be turned on the filter head.