Liquid purification element

Abstract

A multi-layer liquid purification element includes a liquid-permeable top layer and a liquid-impermeable base layer. The base layer has a suction port for drawing-in liquid through the liquid purification element. At least the top layer and the base layer are connected to one another by a liquid-impermeable connection. At least one separate insert is disposed between the top layer and the base layer. A method for producing a liquid purification element, a device for extracting a liquid additive for exhaust-gas purification from a tank and a motor vehicle are also provided.

Claims

1. A multi-layer liquid purification element, comprising: a liquid-permeable top layer; a liquid-impermeable base layer having a suction port for drawing-in liquid through the liquid purification element; a liquid-impermeable connection interconnecting at least said top layer and said base layer; a filter layer disposed between said top layer and said base layer; and two support layers being provided below said filter layer and having aligned passages, said aligned passages overlapping one another for defining an areal duct system.

2. The liquid purification element according to claim 1, wherein said filter layer includes a nonwoven material.

3. A multi-layer liquid purification element, comprising: a liquid-permeable top layer; a liquid-impermeable base layer having a suction port for drawing-in liquid through the liquid purification element; a liquid-impermeable connection interconnecting at least said top layer and said base layer; and at least one separate insert disposed between said top layer and said base layer, said at least one separate insert including at least one support layer, said at least one support layer including at least two support layers having aligned passages, said passages of said at least two support layers being oriented in different directions and said passages of said at least two support layers overlapping one another to form an areal duct system.

4. The liquid purification element according to claim 1, wherein at least one of said support layers includes a stretched material.

5. The liquid purification element according to claim 1, wherein said suction port is formed by an opening in said base layer having a cylindrical projection.

6. The liquid purification element according to claim 1, wherein said connection is formed with a weld seam interconnecting at least said top layer and said base layer.

7. A method for producing a liquid purification element, the method comprising the following steps: a) providing a liquid-permeable top layer; b) providing a liquid-impermeable base layer; c) providing a filter layer between the top layer and the base layer; d) forming a liquid-impermeable connection of at least the top layer and the base layer; e) forming a suction port on the base layer for drawing-in liquid through the liquid purification element; and f) providing two support layers below said filter layer and having aligned passages, the aligned passages overlapping one another for defining an areal duct system.

8. A device for extracting a liquid additive for exhaust-gas purification from a tank, the device comprising: a liquid purification element according to claim 1; and a housing to be installed in the tank, said housing having an extraction port connected to said suction port of said liquid purification element permitting the device to extract liquid additive from the tank through said liquid purification element.

9. A motor vehicle, comprising: an internal combustion engine; an exhaust-gas treatment device for the purification of exhaust gases of said internal combustion engine; a tank for storing a liquid additive; and a device according to claim 8 for extracting the liquid additive from the tank and for supplying the liquid additive to said exhaust-gas treatment device.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) The invention and the technical field will be explained in more detail below on the basis of the figures. It is pointed out that the special exemplary embodiments and features illustrated in the figures, and in particular the proportions illustrated in the figures, are merely schematic. In the figures:

(2) FIG. 1: shows a first embodiment of a liquid purification element,

(3) FIG. 2: shows a second embodiment of a liquid purification element,

(4) FIG. 3: shows a construction of the liquid purification element with two support layers,

(5) FIG. 4: shows a device for the extraction of a liquid additive from a tank with a liquid purification element,

(6) FIG. 5: shows a motor vehicle having a device for the extraction of a liquid additive from a tank, and

(7) FIG. 6: illustrates a method for the production of the liquid purification element.

DESCRIPTION OF THE INVENTION

(8) FIGS. 1 and 2 illustrate in each case a liquid purification element 1 which has a base layer 3 and a top layer 2 which are connected to one another by means of an encircling connection 5 (which forms, for example, a form of quadrangle). The top layer 2 is (preferably entirely or predominantly) permeable to liquid (in the region within the connection) in order that liquid can be drawn into the liquid purification element 1. The base layer 3 has a (single) suction port 4 to which an extraction port of a device for the extraction and delivery of liquid additive from a tank can be connected. The suction port 4 is preferably formed by an opening 12 in the base layer 3 and by a cylindrical projection 13 on the base layer 3. Between the top layer 2 and the base layer 3 there is preferably situated a (single) filter layer 6 by means of which the liquid passing through the top layer 2 into the liquid purification element 1 can be purified. Between the filter layer 6 and the base layer 3 there is preferably arranged (at least) one support layer 7 which ensures the presence of an areal connecting chamber 8 between the filter layer 6 and the base layer 3, which connecting chamber ensures that liquid can flow to the suction port 4 from every location of the filter layer 6 or of the top layer 2. Both the filter layer 6 and also the support layer 7 are labelled as separate inserts in the liquid purification element 1.

(9) In the embodiment as per FIG. 1, there is exactly one support layer 7 which may be formed for example by an (extremely) open-pored material (which, for the usage situation, has practically no filtering action). In the embodiment as per FIG. 2, two support layers 7 are provided, through which flow can pass in different directions 10 in each case and which thus form an areal duct system 11 which forms the described connecting chamber 8. In both cases, the liquid flows through the components of the liquid purification element in the following sequence: top layer 2, filter layer 6, support layer(s) 7 and base layer 3.

(10) A construction with two support layers (as indicated for example in FIG. 2) is explained once again in more detail in FIG. 3, wherein the two support layers 7, which each have passages 9, are illustrated three-dimensionally. Said passages 9 in the individual support layers 7 are oriented in each case in different directions 10 and overlap or intersect with one another in each case. A duct system 11 is thus formed which in turn ensures the presence of the described connecting chamber within the liquid purification element 1. This permits a liquid flow 30 to the suction port (not illustrated in FIG. 3) on the base layer from every location in the support layers 7, such that the top layer (not illustrated here) and/or the filter layer (not illustrated here) can be connected, in large-area form, to the suction port. Here, the expression large-area means that the entire area of the top layer and of the filter layer (within the liquid-impermeable connection) is connected in liquid-conducting fashion to the suction port.

(11) FIG. 4 shows a device 14 for the extraction of a liquid additive for exhaust-gas purification (in particular urea-water solution) from the tank. In FIG. 4, (only) the tank bottom 29 into which the device 14 or the housing 16 of the device 14 is inserted is illustrated. On the housing 16 there is provided an extraction port 17 through which liquid can be drawn out of the tank. The suction port 4 of a described liquid purification element is connected to the extraction port 17 such that liquid can be drawn through the liquid purification element 1 into the extraction port 17. A suction line 27 runs from the extraction port 17 to a pump 26 arranged in the housing 16. The liquid delivered by the pump 26 is supplied by the device 14 at the supply port 28. The liquid purification element 1 is arranged on the device 14 in a receptacle 24 and is adapted to an outer surface of the housing 16. Furthermore, a cover element 25 may be provided which permanently fixes the liquid purification element to the housing 16 or to the outer surface of the housing 16.

(12) FIG. 5 shows a motor vehicle 18 having an internal combustion engine 19 and having an exhaust-gas treatment device 20 for the purification of the exhaust gases of the internal combustion engine 19. In the exhaust-gas treatment device 20 there is provided an SCR catalytic converter 23 for carrying out the method of selective catalytic reduction. Liquid additive can be supplied from a tank 15 to the exhaust-gas treatment device 20 via an injector 22 and a line 21 by a device 14.

(13) FIG. 6 shows a stage during a production process for the production of liquid purification elements 1. It can be seen in FIG. 6 that the top layer 2, the base layer 3 and a filter layer 6 are provided in each case in the form of an endless material strip from a coil 31. The filter layer 6 illustrated here is to be understood as an example for any desired separate insert. A support layer, for example, may additionally or alternatively also be provided between the top layer 2 and the base layer 3. The top layer 2, the filter layer 6 and the base layer 3 form a layer pack 33 which can be severed along cut lines 32 to form liquid purification elements 1. The liquid-impermeable connections 5 that delimit the individual liquid purification elements 1 may be produced before or after the severing of the individual liquid purification elements 1 along the cut lines 32.

(14) By way of precaution, it is also pointed out that the combinations of technical features shown in the figures are not generally imperative. For example, technical features from one figure may be combined with other technical features from another figure and/or from the general description. The only exception to this is if the combination of features has been explicitly referred to here and/or a person skilled in the art identifies that the basic functions of the device can no longer be realized otherwise.

LIST OF REFERENCE NUMERALS

(15) 1 Liquid purification element 2 Top layer 3 Base layer 4 Suction port 5 Connection 6 Filter layer 7 Support layer 8 Connecting chamber 9 Passage 10 Direction 11 Duct system 12 Opening 13 Cylindrical projection 14 Device 15 Tank 16 Housing 17 Extraction port 18 Motor vehicle 19 Internal combustion engine 20 Exhaust-gas treatment device 21 Line 22 Injector 23 SCR catalytic converter 24 Receptacle 25 Cover element 26 Pump 27 Suction line 28 Supply port 29 Tank bottom 30 Liquid flow 31 Coil 32 Cut line 33 Layer pack