DE102018215902A1 - Fluid tank - Google Patents

Abstract

A fluid tank (2) with a tank volume (4a, 4b) for storing a fluid (3) has at least one slosh wall (8, 8a, 8b) which is designed to reduce sloshing and undulation movements of the fluid (3). At least one filter element (16, 16a, 16b) is arranged in the at least one slosh wall (8, 8a, 8b) and is designed to filter the fluid (3).

Description

The invention relates to a fluid tank for storing a fluid, in particular a fluid reducing agent.

State of the art

In order to reduce nitrogen oxides (NO _x ), which are contained in the exhaust gases of an internal combustion engine, in particular a diesel engine, a liquid reducing agent ("fluid"), in particular a urea water solution ("AdBlue" O), is often injected into an injected the exhaust tract of the internal combustion engine.

In a catalytic converter located downstream of the injection point, the nitrogen oxides contained in the exhaust gases react with the reducing agent and are reduced in nitrogen and water.

The reducing agent is kept in a fluid tank. The reducing agent can contain foreign bodies and / or dirt particles that can damage and / or clog the injection system.

In particular in the case of a gasoline engine, a fluid tank can be provided for storing demineralized water. Demineralized water can be injected together with the fuel into the combustion chamber of the internal combustion engine in order to reduce the combustion temperature and thus the thermal load on the components. The water also binds soot particles that are formed during combustion.

Movements of the fluid tank, e.g. in a moving vehicle can cause the fluid to spill up in the fluid tank. This can have the consequence that there is temporarily no fluid at the removal point of the fluid tank and the fluid supply to the injection system is interrupted.

It is an object of the invention to provide a fluid tank for a fluid, in particular a liquid reducing agent, which avoids or at least reduces the problems mentioned.

Disclosure of the invention

According to one exemplary embodiment of the invention, a fluid tank limits a tank volume which is provided for storing a fluid, in particular a fluid reducing agent or demineralized water. There is at least one slosh wall in the tank volume, which is designed to prevent or at least reduce sloshing and wave movements of the fluid, such as can be caused in particular by movements and fluid noise in the fluid tank resulting therefrom. At least one filter element, which is designed to filter fluid flowing through, is arranged in the at least one slosh wall.

Embodiments of the invention also include an injection system for injecting a fluid reducing agent into an exhaust line of an internal combustion engine, the injection system having a metering module arranged on an exhaust duct of the exhaust line and a fluid tank according to the invention. The metering module is designed to inject the reducing agent into the exhaust gas duct, and the fluid tank is designed to store the fluid to be injected into the exhaust gas duct.

By integrating at least one filter element into at least one slosh wall according to the invention, a space-saving and inexpensive construction of a fluid tank can be realized, which makes it possible both to provide filtered fluid and to prevent the fluid stored in the fluid tank from undesirably sloshing up. In this way, reliably filtered fluid can be made available to the injection system, even when the tank is moved.

In one embodiment, at least one filter window is formed in the at least one slosh wall, and the at least one filter element is arranged in the at least one filter window. With the help of filter windows formed in the at least one slosh wall, the filter elements can be arranged particularly easily in the at least one slosh wall. In particular, the filter elements can be removably arranged in the filter windows, so that the filter elements can be easily removed and cleaned or replaced if necessary.

As an alternative or in addition, the at least one slosh wall can also be designed such that it, e.g. for maintenance purposes, can be easily removed from the fluid tank and reinserted.

In one embodiment, a lower edge of the at least one filter element is arranged at a distance of at least 15 mm, for example at a distance of 15 mm to 25 mm, in particular 20 mm, from a bottom of the fluid tank. Such an arrangement of the filter element, spaced from the bottom of the fluid tank, ensures that sediments in the fluid collect in a sediment area below the at least one filter element without clogging or blocking the flow through the filter element.

In one embodiment, the at least one slosh wall divides the tank volume of the fluid tank into a dirt area and a clean area. Filtered clean fluid can be made available to the injection system from the clean area of the tank volume.

In one embodiment, a sedimentation stage is formed on a side of the at least one slosh wall facing the dirt area, which supports the separation of sediment at the bottom of the dirt area and thereby reduces the risk of clogging and / or blocking of the at least one filter element by separated sediments.

In one embodiment, the at least one filter element is linear, i.e. formed as a substantially planar plate. In an alternative embodiment, the at least one filter element is cylindrical. The at least one filter element can in particular be designed as an easily manageable and replaceable, essentially cylindrical filter cartridge.

The at least one slosh wall can also be linear, i.e. be designed as an essentially planar plate, accordion-shaped or cylindrical. The surface available for filtering the fluid can be enlarged with the same dimensions of the fluid tank as compared to a linearly formed slosh wall by means of a cylinder-shaped or accordion-shaped slosh wall. The maximum possible fluid flow through the filter elements, and thus the maximum possible withdrawal quantity per unit of time, can be increased in this way without increasing the dimensions of the fluid tank.

In one embodiment, the fluid tank has at least two slosh walls, in each of which at least one filter element is arranged. The at least two slosh walls divide the tank volume of the fluid tank into a dirt area, a first clean area and a second clean area. More than two slosh walls can also be provided, which form more than two clean areas. The filter elements in the various slosh walls can have different mesh sizes / pore sizes. In particular, the filter elements can be designed in such a way that the fluid flows in sequence through filter elements with decreasing mesh sizes / pore sizes before it reaches the last clean area (clean area).

Particles of different sizes can be filtered out of the fluid in stages. In this way, particularly pure fluid can be provided in the clean area without the risk that the filter elements, in particular the filter elements with a small mesh size / pore size, clog too quickly.

In one embodiment, the fluid tank has at least one protective element, for example a protective wall. The at least one protective element is arranged and configured on at least one side of the at least one slosh wall to protect the slosh wall and in particular the at least one filter element from mechanical influences, in particular from ice and / or liquid hammer.

The protective element can be made of the same material as the at least one slosh wall or of a different material. The protective element can in particular be made of an elastic and / or porous material, for example a PU foam, which is suitable for elastically absorbing mechanical effects / impacts in order to prevent mechanical damage to the protective element and / or the slosh wall.

In one embodiment, the at least one protective element is arranged at a distance of 5 mm to 10 mm from the at least one slosh wall. A distance in a range of 5 mm to 10 mm has proven to be particularly suitable for protecting the swash wall from damage.

In one embodiment, at least one groove for receiving the at least one slosh wall is formed in / on a limitation of the tank volume, for example in / on a wall, a floor and / or a ceiling of the fluid tank. The slosh wall can be inserted into such a groove in order to detachably fix the slosh wall to a limitation of the tank volume.

In one embodiment, the at least one slosh wall is glued or welded to at least one limitation of the tank volume in order to fix the slosh wall particularly securely to the limitation of the tank volume.

A slosh wall extending between at least two limits of the tank volume gives the fluid tank additional rigidity.

In one embodiment, the at least one filter element is interchangeable, ie it can be easily removed from the slosh wall, so that it can be easily replaced if it is clogged and / or damaged. The at least one filter element can also be replaced on a regular basis, to prevent constipation and / or damage.

In one embodiment, the at least one slosh wall and / or the at least one filter element can be heated in order to thaw frozen fluid and / or to prevent the fluid from freezing.

For this purpose, the slosh walls and / or the filter elements can each be equipped with at least one heating element, in particular an electrical heating element.

The electrical heating element can for example be an ohmic heating element, e.g. a heating coil, or a PTC heating element. A large-scale heating effect can be achieved by heating the slosh walls and / or the filter elements. In this way, even at low ambient temperatures, an amount of thawed fluid can be made available that is sufficient for the operation of the injection system.

Figure list

• 1 shows an exhaust system of an internal combustion engine with a metering module for injecting a reducing agent into an exhaust duct of the exhaust system in a schematic representation.
• 2nd shows a schematic side sectional view of a fluid tank according to an embodiment of the invention.
• 3rd shows a schematic section along the in the 2nd line shown CC.
• 4th shows a plan view of a region of a fluid tank according to a further embodiment of the invention.
• 5 shows a side view of the in the 4th shown area.
• 6 shows a plan view of a fluid tank according to a further embodiment of the invention.
• 7 shows a plan view of an area of a fluid tank with a slosh wall and a protective element arranged in front of the slosh wall.
• 8th shows a plan view of an area of the fluid tank according to a further embodiment of the invention in the vicinity of the swash wall.
• 9 shows a section through in the 8th shown swashwall.

Figure description

Embodiments of the invention are described below with reference to the accompanying figures.

1 shows an exhaust line 52 of an internal combustion engine 54 with an injection system 55 for injecting a reducing agent 3rd into an exhaust duct 53 of the exhaust system 52 in a schematic representation.

The injection system 55 includes a dosing module 51 that in the flow direction of the exhaust gases 50 of the internal combustion engine 54 between the internal combustion engine 54 and an SCR catalyst 57 is arranged. The dosing module 51 contains an injector 56 , which is formed, a fluid reducing agent 3rd in the exhaust duct 53 to inject.

The reducing agent to be injected 3rd is by a feed pump 58 from a fluid tank 2nd removed and the dosing module 51 fed. The dosing module 51 injects the reducing agent 3rd with increased pressure in the exhaust duct 53 of the exhaust system 52 on. In the exhaust duct 53 the injected reducing agent mixes 3rd with those through the exhaust duct 53 flowing exhaust gases 50 and reacts in the downstream of the dosing module 51 arranged SCR catalyst 57 with those in the exhaust 50 contained nitrogen oxides (NO _x ), which are reduced to N ₂ and H ₂ O.

2nd showed a schematic side sectional view of a fluid tank 2nd according to an embodiment of the invention. 3rd shows a schematic sectional view along the in the 1 line shown CC.

The one in the 2nd and 3rd fluid tank shown 2nd includes an upper tank shell 6a and a lower tank shell 6b . The two fuel tanks 6a , 6b are along a connecting line 7 , for example by a welded or adhesive connection. The upper tank pan 6a and the lower tank shell 6b limit a tank volume 4a , 4b that is used to store a fluid 3rd , in particular a fluid reducing agent 3rd , such as an aqueous urea solution, or of demineralized water is provided and suitable.

To wave and sloshing movements in the tank volume 4a , 4b stored fluids 3rd , especially as a result of movements of the fluid tank 2nd can be generated, is located in the tank volume 4a , 4b a splash wall 8th . The swash wall 8th extends from a floor 18th of the fluid tank 2nd to a blanket 20th of the fluid tank 2nd .

The swash wall 8th divides the tank volume 4a , 4b in one in the 2nd and 3rd Dirt area shown on the left 4a and one in the 2nd and 3rd Clean area shown on the right 4b .

In the ceiling 20th of the fluid tank 2nd is a filler neck 10th formed, which allows fluid (reducing agent or demineralized water) 3 in the dirt area 4a of the fluid tank 2nd fill in.

On the ground 18th of the clean area 4b there is a removal device 12th which in particular the feed pump 58 contains and allows fluid 3rd from the clean area 4b of the tank volume 4a , 4b and the dosing module 51 feed.

The removal device 12th can in addition to the feed pump 58 a filter 60 and / or a heater 62 contain.

In the swash wall 8th are openings / windows 14 formed, in each of which a filter element 16 is arranged. Through the filter elements 16 can fluid 3rd from the dirt area 4a in the clean area 4b of the tank volume 4a , 4b stream. Fluid 3rd that through the openings / windows 14 flows through the filter elements 16 filtered. Dirt particles 17th that are larger than the mesh size / pore size of the filter elements 16 are out of the fluid 3rd filtered and can not in the clean area 4b of the tank volume 4a , 4b reach.

In the clean area 4b there is therefore filtered / clean fluid 3rd available from the removal device 12th from the clean area 4b removed and the dosing module 51 can be supplied.

The openings / windows 14 are at a distance (at a height) d of at least 15 mm from the ground 18th of the fluid tank 2nd arranged. This increased arrangement of the openings / windows 14 is in front of the swash wall 8th on the ground 18th the dirt area 4a a sedimentation area 15 trained in which there is a sediment of dirt particles 17th can accumulate without the filter elements 16 to clog.

In the ceiling 20th of the tank 2nd is an opening 22 through which the filter elements 16 can be removed, cleaned and / or replaced if necessary. The opening 22 is through a removable cover 24th can be closed with a flow-tight seal.

4th shows a top view of an area of a fluid tank 2nd in the area of the Schwappwand 8th according to a further embodiment of the invention. 5 shows a side view of the swash wall 8th from the in the 4th drawn viewing direction R.

In the in the 4th and 5 shown embodiment extends the slosh wall 8th between two side walls 19a , 19b of the fluid tank 2nd . The swash wall 8th is shaped like an accordion and comprises several swashwall segments 81 - 84 that at obtuse angles α _1,2,3 , ie in angles α _1,2,3 that are larger than 90 ° are arranged to each other. The angles α _1,2,3 between the swashwall segments 81 - 84 can be identical or different.

In the exemplary embodiment shown, there are segments in each of the swashwall 81 - 84 two openings / windows 16 formed, in each of which a filter element 18th is arranged (see 5 ). In each of the swashwall segments 81 - 84 can also have more or less than two openings / windows 16 trained and more or less than two filter elements 18th be arranged.

In the side walls 19a , 19b or in the ceiling 20th and in the ground 18th of the fluid tank 2nd is a groove 26 trained in which the slosh wall 8th is introduced (see 4th ) to the swash wall 8th to fix.

The grooves 26 and the swash wall 8th can in particular be designed such that the width b of a gap between the slosh wall 8th and the side walls 19a , 19b or the ceiling 20th and the floor 18th of the fluid tank 2nd is not more than 0.5 mm over a length of at least 6 mm. The grooves 26 and the swash wall 8th thus form a labyrinth seal that prevents dirt particles 17th through the gap from the dirt area 4a in the clean area 4b of the tank volume 4a , 4b can reach. The swash wall 8th with the filter elements 16 can still be easily replaced by pulling out the grooves 26 is pulled.

Alternatively, the swash wall 8th in the grooves 26 glued or welded.

6 shows a top view of a fluid tank 2nd according to a further embodiment of the invention.

In the in the 6 Embodiment shown are in the tank volume 4a , 4b , 4c of the fluid tank 2nd two slosh walls 8a , 8b with previously formed sedimentation areas 15a , 15b arranged.

The two slosh walls 8a , 8b divide the tank volume 4a , 4b , 4c of the fluid tank 2nd in a dirt area 4a , a first clean area 4b and a second clean area ( Clean area) 4c . The filler neck 10th allows fluid 3rd in the dirt area 4a fill, and the fluid sampling device 12th is in the second clean area (clean area) 4c arranged.

The one in the second swash wall 8b arranged filter elements 16b in particular have a smaller mesh size / pore size than that in the first slosh wall 8a arranged filter elements 16a . The one in the first swash wall 8a arranged filter elements 16a cause a first (pre) filtering, through which coarse particles from the fluid 3rd be filtered.

The one in the second swash wall 6b arranged filter elements 16b effect a second (fine) filtering, through the fine particles that make up the first filter element 16a could happen from the already roughly filtered fluid 3rd be removed. Such a combination of filter elements 16a , 16b With different mesh sizes / pore sizes, even fine particles can be reliably removed from the fluid 3rd to remove without the risk that the filter elements 16a , 16b , especially those in the second swash wall 6b arranged (fine) filter elements 16b , clog in a short time.

The one in the first swash wall 8a arranged filter elements 16a can have a mesh size / pore size of approx. 50 µm, for example, and that in the second slosh wall 8b arranged filter elements 16b can have, for example, a mesh size / pore size of approximately 20 μm.

7 shows a top view of an area of a fluid tank 2nd with a splash wall 8th and one in front of the swash wall 8th arranged protective element 28 . The protective element 28 is on the side of the swash wall 8th arranged that the dirt area 4a of the tank volume 4a , 4b is facing.

The protective element 28 extends essentially parallel to the slosh wall 8th and is for example at a distance a of 5 mm to 10 mm in front of the slosh wall 8th arranged. The protective element 28 is trained, the swash wall 8th Protect against mechanical damage, especially against damage caused by ice and / or fluid hammer.

The protective element 28 extends almost completely across the width and height of the slosh wall 8th to protect them almost completely.

Alternatively or additionally, a protective element (not shown) can be used 28 also on the other side of the swash wall 8th be arranged, the clean area 4b of the tank volume 4a , 4b is facing.

The protective element 28 can be made of the same material as the swash wall 8th or be made of another material. The protective element 28 can in particular be made of an elastic and / or porous material, for example a PU foam.

The 8th and 9 show a further embodiment of a fluid tank according to the invention 2nd .

8th shows a top view of an area of the fluid tank 2nd in the area of the Schwappwand 8th , and 9 shows a section through in the 8th shown swashwall 8th .

In the in the 8th and 9 The embodiment shown is the filter element 16 as a cylindrical filter element 16 educated.

The cylindrical filter element 16 can be used as an easily replaceable filter cartridge 16 be trained. The axis A of the cylindrical filter element 16 can be aligned in particular in the horizontal or in the vertical direction.

In the in the 8th and 9 The embodiment shown is the axis A of the filter element 16 aligned in the vertical direction. The filter element 16 lies with its bottom 34 on one on the ground 18th of the fluid tank 2nd trained sedimentation level 30th on. The sedimentation level 30th for example, has a height h of at least 15 mm from the floor 18 mm.

A lower area of the filter element 16 , ie to the bottom 34 of the filter element 16 adjacent area, is of an annular filter element fixation 35 surround the filter element 16 on the ground 18th of the fluid tank 2nd to fix.

In the bottom 34 of the filter element 16 is a fluid opening 32 educated. The fluid opening 32 is in fluid communication with a fluid channel 36 who is in the ground 18th of the fluid tank 2nd is trained.

Fluid 3rd that through the side wall designed as a filter 33 that the jacket of the cylindrical filter element 16 forms from the dirt area 4a of the fluid tank 2nd in a central area 37 of the filter element 16 has flowed through the bottom 34 of the filter element 16 trained fluid opening 32 and the fluid outlet channel 36 from the filter element 16 in the clean area 4b of the fluid tank 2nd .

Between the filter element 16 and the swashwall 8th is a semi-circular fluid inlet channel 9 trained who fluid it 3rd from the dirt area 4a enables, along the entire circumference, in particular also from the (rear) side of the filter element 16 who the swashwall 8th is facing through the side wall 33 of the filter element 16 in the central area 37 of the filter element 16 to pour. In this way, the entire circumference of the cylindrical filter element 16 used for filtering to get the maximum possible throughput through the filter element 16 to increase.

An upper end of the filter element 16 is from a lid 38 enclosed. The lid 38 has an internal thread 40 that with a corresponding external thread 42 that on the ceiling 20th of the fluid tank 2nd is formed, can be screwed. This enables the filter element 16 by screwing the lid on 38 in the fluid tank 2nd to fix and the fluid tank 2nd to be sealed fluid-tight. Between the lid 38 and the fluid tank 2nd can be a sealing ring 39 be provided.

In an embodiment not shown in the figures, in which the axis A of the filter element 16 oriented horizontally are the opening 22 to remove the filter element 16 and the external thread 42 in / on a side wall 19a , 19b of the fluid tank 2nd educated.

The slosh walls 8th , 8a , 8b and / or the filter elements 16 , 16a , 16b can each use at least one heating element 44 be equipped, which allows frozen fluid 3rd in the fluid tank 2nd thawing and / or freezing the fluid 3rd to prevent. By heating the slosh walls 8th , 8a , 8b and / or the filter elements 16 , 16a , 16b a large heating effect can be realized. This can cause a large amount of thawed fluids in a short time 3rd to provide.

Although a heating element 44 in the 9 only in connection with a cylindrical filter element 16 shown, those skilled in the art understand that heating elements 44 also in combination with planar filter elements 16 can be used as in the 2nd to 7 are shown.

Claims (15)

Fluid tank (2) with a tank volume (4a, 4b) for storing a fluid (3) and with at least one slosh wall (8, 8a, 8b), which is designed to reduce sloshing and wave movements of the fluid (3); characterized in that at least one filter element (16, 16a, 16b) is arranged in the at least one slosh wall (8, 8a, 8b) and is designed to filter the fluid (3). Fluid tank (2) after Claim 1 , wherein at least one filter window (14) is formed in the at least one slosh wall (8, 8a, 8b), and wherein the at least one filter element (16, 16a, 16b) is arranged in the at least one filter window (14). Fluid tank (2) after Claim 1 or 2nd , wherein the at least one filter element (16, 16a, 16b) is arranged at a distance (d) of at least 15 mm from a bottom (18) of the fluid tank (2). Fluid tank (2) according to one of the preceding claims, wherein the at least one slosh wall (8, 8a, 8b) divides the tank volume (4a, 4b) of the fluid tank (2) into a dirt area (4a) and a clean area (4b). Fluid tank (2) after Claim 4 A sedimentation stage (30) is formed on a side of the at least one slosh wall (8, 8a, 8b) facing the dirt region (4a). Fluid tank (2) according to one of the preceding claims, wherein the at least one filter element (16, 16a, 16b) is plate-shaped or cylindrical Fluid tank (2) according to one of the preceding claims, wherein the at least one slosh wall (8, 8a, 8b) is plate-shaped, accordion-shaped or cylindrical. Fluid tank (2) according to one of the preceding claims with at least two slosh walls (8a, 8b), in each of which at least one filter element (16, 16a, 16b) is arranged, the at least two slosh walls (8a, 8b) representing the tank volume (4a, 4b) divide the fluid tank (2) into a dirt area (4a), a first clean area (4b) and a second clean area (4c). Fluid tank (2) according to one of the preceding claims with at least one protective element (28) which is arranged on at least one side of the at least one slosh wall (8, 8a, 8b), the at least one protective element (28) being formed, the at least one To protect the filter element (16, 16a, 16b) from mechanical influences, in particular from ice and liquid hammer. Fluid tank (2) after Claim 9 , wherein the at least one protective element (28) is arranged at a distance (a) of 5 mm to 10 mm from the at least one slosh wall (8). Fluid tank (2) according to one of the preceding claims, wherein at least one groove (26) for receiving the at least one slosh wall (8, 8a, 8b) is formed in a limitation of the tank volume (4a, 4b). Fluid tank (2) according to one of the preceding claims, wherein the at least one slosh wall (8, 8a, 8b) is bonded or welded to at least one limitation (18, 19a, 19b, 20) of the tank volume (4a, 4b). Fluid tank (2) according to one of the preceding claims, wherein the at least one filter element (16, 16a, 16b) is interchangeable. Fluid tank (2) according to one of the preceding claims, wherein the at least one slosh wall (8, 8a, 8b) and / or the at least one filter element (16, 16a, 16b) can be heated. Injection system (55) for injecting a fluid reducing agent (3) into an exhaust line (52) of an internal combustion engine (54), the injection system comprising: a metering module (51) which is arranged on an exhaust gas duct (53) of the exhaust gas line (52) and is designed to inject the reducing agent (3) into the exhaust gas duct (53); and a fluid tank (2) according to one of the preceding claims, which is designed to store the reducing agent (3) to be injected.

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