The present invention relates to a filter assembly for a fluid to be filtered, in particular, fuel or oil, comprising a filter housing and comprising at least two filter elements.
Filter elements are used in motor vehicles, for instance, to remove impurities from operating fluids like fuel and oil. Typically, exactly one filter element is provided for a fluid to be filtered. The size of the filter element limits a maximum possible volume flow of the fluid to be filtered. However, the installation space available is not always large enough or shaped as needed.
EP 0 991 457 B1 discloses a filter system in which a plurality of separate, hollow, cylindrical filter housings each comprising a filter element are bolted onto a shared filter head. The filter head is configured so that a fluid is able to flow in parallel through the filter housings comprising the filter elements. The filter head comprises connections for introducing the fluid to be filtered and for discharging the filtered fluid. The specific filter head is intended to reduce the number of connecting lines required in order to connect the plurality of filter housings to a pre-filtration line for a fluid to be filtered. However, the elaborate filter head significantly increases the overall height in the vertical direction.
US 2011/0 089 101 A1 discloses a fuel filter in which two hollow, cylindrical filter cartridges allowing parallel through-flow are arranged in a shared housing interior of a filter housing, wherein each filter cartridge is surrounded with a hydrophobic mesh in order to separate out water contained in the fuel. The filter cartridges are mounted onto maintenance covers screwed into the filter housing from the underside, so that the filter cartridges can be easily replaced. Because the filter cartridges are arranged in the shared housing interior, only a slight—if any—reduction in the overall size of the fuel filter as a whole is produced, in comparison to the use of a larger filter cartridge. Moreover, there is no increase in flexibility for the design of an outer contour of the filter housing.
This disclosure addresses the problem of providing a more inexpensively-manufactured filter assembly that makes it possible, even in confined installation spaces, to accommodate a sufficiently large filter surface for a predetermined volume flow of a fluid to be filtered.
According to the present invention, a filter assembly for a fluid to be filtered, in particular fuel or oil, is provided with a filter housing. The filter housing has a housing lower part, configured as a single piece. This makes the housing lower part simple and inexpensive to fabricate. At least one fluid inlet for the fluid to be filtered is provided in the housing lower part. The housing lower part is configured so as to comprise a plurality of filter pots. The filter pots are arranged side by side, adjacent to one another in a shared plane. The housing lower part can thus be flexibly adapted to an installation space of a complex or jagged shape, in particular, to a very flat installation space. The filter pots are fluidically connected to one another via side wall passages. This makes it possible to endow the filter pots with a parallel through-flow. The side wall passages may be configured as radial channels, preferably as slits in the side walls, which are open from a separation plane of the housing parts, in order to achieve an unencumbered demolding therethrough.
The plurality of filter pots also make it possible to filter a predetermined volume flow of the fluid. The filter housing further comprises a housing upper part for closing the filter pots. The housing upper part is typically placed in a sealing, i.e., fluid-tight manner on the filter housing. For this purpose, the filter housing and housing upper part may be adhered to one another. A fluid manifold that comprises at least one fluid outlet for the filtered fluid flowing out of the filter pots is configured on the housing upper part. The filter assembly additionally comprises at least two filter elements, one being arranged in each of the filter pots of the filter housing. Each of the filter pots is thereby divided into an antechamber for the fluid to be filtered and a post-filtration chamber for filtered fluid. The fluid manifold is typically opened to the post-filtration chambers of each of the filter pots. That is to say, filtered fluid can flow from the respective post-filtration chambers into the fluid manifold.
It may be provided that the filter assembly has, in each case, more than one fluid inlet and/or fluid outlet, such as a pre-filtration liquid inlet and an inlet for fuel returned from an internal combustion engine, and/or two post-filtration liquid outlets that can be connected to separated fuel supply systems.
The housing upper part may be configured as a single piece or as a plurality of pieces. It is configured so as to comprise one cover element for each filter pot. With a multi-piece housing upper part, at least two of the cover elements may be structurally identical.
An advantageous embodiment provides that the cover elements each comprise a lengthwise segment of the fluid manifold. This makes it possible to achieve a compact structural design.
In an especially preferred embodiment, it is provided that the cover element and the respectively-associated lengthwise segment are integrated as a single piece with one another. The fluid manifold is then configured at least in some sections as a component of the housing upper part. This makes it possible to simplify the fabrication and mounting of the filter assembly.
In an advantageous embodiment, the fluid manifold is longitudinally divided. Preferably, a lower-side partial section of the fluid manifold is formed of a lengthwise segment that is integrated with a cover element. This further simplifies fabrication and enables an especially flat structural design of the filter assembly.
In a preferred embodiment, the filter assembly is characterized in that the filter elements are supported on the housing upper part. Advantageously, the filter elements are clamped, embedded, or integrally fastened, preferably welded, onto the housing upper part. Alternatively or additionally, the filter element may be plugged—preferably, plugged in a sealing manner—onto a socket section of the housing upper part. The socket section may be sealed off by an O-ring or a sealing seat, which is preferably present at or abuts against an end plate of the filter element.
This simplifies the mounting of the filter assembly. The filter elements may be pre-mounted onto the housing upper part, for this purpose. At the same time, it can be ensured that the filter elements are attached in a fluid-tight manner to the housing upper part, so that no leakage flow will occur between the respective antechambers and post-filtration chambers.
In an advantageous embodiment, the filter elements are round elements, in particular, with a filter medium folded into the shape of a star. This enables an especially compact design for the individual filter pots. In an alternative, also advantageous embodiment, the filter elements are flat elements, in particular with a filter medium folded into a zigzag shape. This enables an exceptionally flat design for the filter assembly.
Preferably, at least two of the filter pots are connected fluidically in parallel to one another on the pre-filtration side. The fluid can then flow in parallel through the filter elements in the at least two filter pots. That is to say, the antechambers in the filter pots are fluidically connected to one another. This makes it possible to obtain a larger effective overall filter element when individual small filter elements are being used.
In an advantageous development, it is provided that a heating element for the fluid and/or a water separator for separating out water contained in the fluid is/are arranged in one of the filter pots, preferably in a filter pot that allows a serial through-flow, which is especially preferably arranged on the inflow side as a first filter pot of the filter assembly or is a central pot that allows a serial through-flow. The filter pot allowing a serial through-flow is thus connected upstream or downstream of the other filter pots. This makes it possible to integrate additional functions such as heating of the fluid and/or separation of water from the fluid. The consequently requisite equipment need then be provided only once for the entire filter assembly, and not for each individual filter pot or each individual filter element, ie., as a plurality.
In an advantageous embodiment, it is provided that the housing lower part is configured as an injection-molded part. Preferably, the housing lower part is composed of polyamide. Particularly preferably, PA66 is used. The housing upper part is typically also configured as an injection-molded part, preferably made of polyamide. Advantageously, one or both housing parts may be at least partially composed of an electrically conductive plastic, which is advantageous in order to be able to discharge static electricity created by the through-flow of fuel. Here, the filter assembly in an especially advantageous embodiment may have at least one connection for establishing electrical contact for discharging static electricity, which is preferably arranged at the fluid inlet and/or fluid outlet.
In an advantageous embodiment, the filter pots differ from one another in the respective overall heights and/or diameters thereof. The filter pots are consequently configured so as to have different depths. This enables an especially favorable fit of the filter assembly into jagged installation spaces.
In another embodiment, it may be provided that the housing upper part and the housing lower part are connected to one another in a fluid-tight manner, in particular, welded together on a separation plane. The separation plane may then run normal to a longitudinal axis of the filter pots, or run at an angle to the longitudinal axis of the filter pots. Alternatively, the separation plane may be stepped, in particular, have a plurality of steps, wherein preferably at least one separation plane section that runs normal to a longitudinal axis of the filter pots is present and at least one separation plane section that runs at an angle to the longitudinal axis of the filter pots is present. This enables even better adaptation to an installation space, not only in the plane, but also at an inclination of a limitation of the installation space.
A welding seam provided between the housing lower part and the housing upper part typically runs circumferentially around. The welding seam may advantageously run in a seam plane. Alternatively, the welding seam may extend along a three-dimensional curve. Welding enables a simple, inexpensive, space-conserving, and reliably fluid-tight connection of the housing lower part to the housing upper part.
Finally, it may be provided, alternatively or additionally, that a bracing is provided between at least two adjacent filter pots, the bracing preferably constituting or comprising at least one fastening device, in particular, a fastening eyelet or fastening tab, which can be used to fasten the filter assembly, for example, onto a motor vehicle, in particular, in the undercarriage region.
The filter pots may each have a round, elliptical, polygonal, in particular, rectangular or hexagonal cross-sectional shape. Preferably, all of the filter pots of the filter assembly have the same cross-sectional shape. Alternatively, however, different cross-sectional shapes may be combined within one filter assembly. Selecting a suitable cross-sectional shape for the filter pots makes it possible to further adapt the filter assembly to the installation space available.
Additional advantages of the invention result from the description and the drawings. The features described in the foregoing and elaborated even further may be used individually by themselves or with other features in any combination.
In the drawings:
FIG. a illustrates a schematic top view of a first embodiment of a filter assembly 10 according to the present invention.
The filter housing 12 comprises a housing lower part 16 and a housing upper part 18. The housing lower part 16 and the housing upper part 18 are in each case configured as a single piece, each as an injection-molded part. The two housing parts may be composed, for example, of polyamide. The housing upper part 18 is welded onto the housing lower part 16 in a fluid-tight manner. The housing upper part 18 constitutes four cover elements 20 for the four filter pots 14. Each of the cover elements 20 completely covers the respectively-associated filter pot 14.
The filter assembly 10 has a fluid inlet 22. The fluid inlet 22 is arranged on the housing lower part 16. Fluid to be filtered can flow through the fluid inlet 22 into the filter pots 14. The filter assembly 10 further comprises a fluid manifold 24. The fluid manifold 24 is configured on the housing upper part 18. The fluid manifold 24 opens into a fluid outlet 26. Filtered fluid can flow out from the filter housing 12 through the fluid outlet 26. The fluid manifold 24 is formed of lengthwise segments 28 that are each configured on one of the cover elements 20. In the embodiment of
The filter pots 14 are fluidically connected to one another via side wall passages 40. That is to say, the antechambers 36 in the filter pots 14 can communicate with one another through the side wall passages 40. The filter pots 14 are thus connected in parallel on the pre-filtration side. The fluid manifold 24 opens toward each of the filter pots 14. That is to say, each post-filtration chamber 38 has a fluidic connection to the manifold 24. Consequently, the fluid to be filtered can flow through the filter elements 30 in parallel.
The fluid manifold 24 broadens, in the through-flow cross-section thereof, toward the fluid outlet 26. This makes it possible to prevent the flow rate of the filtered fluid in the fluid manifold 24 from increasing toward the fluid outlet 26 during operation of the filter assembly 10. Through the widening of the through-flow cross-section of the fluid manifold 24 illustrated in
A fluid manifold 24 is configured on the housing upper part 18. The fluid manifold 24 is configured here so as to be longitudinally divided. The fluid manifold 24 consequently comprises here a bottom section 24a and a cover section 24b. The bottom section 24a and the cover section 24b are adjacent to one another in a longitudinal seam 42. The longitudinal seam 42 is here configured as a welding seam. It is thus possible to achieve a fluid-tight connection between the bottom section 24a and the cover section 24b. The bottom section 24a is configured as a single piece, integrated with the housing upper part 18. Connecting pieces 44 may extend one into each of the filter pots 14 from the bottom section 42. Through the connecting pieces 44, filtered fluid can flow into the fluid manifold 24. A fluid outlet 26 of the fluid manifold 24 is here configured as a single piece integrated with the bottom section 24a or the housing upper part 18.
The filter pots 14 are configured in a housing lower part 16 of a filter housing 12. The housing lower part 16 is closed on the upper side by a housing upper part 18 of the filter housing 12. For this, here, the housing lower part 16 is horizontally circumferentially welded to the housing upper part 18. A fluid inlet 22 is arranged on the housing lower part 16. The housing upper part 28 has a fluid outlet 26.
Adjacent filter pots 14 are fluidically connected to one another via side wall passages 40 that allow a through-flow. The side wall passages 40 are here configured as channels in partition regions 46 of the housing lower part 16 between the filter pots 40.
A fluid manifold 24 is configured in the housing upper part 18. The fluid manifold 24 opens into the fluid outlet 26. Here, there is one cover element 20 of the housing upper part 18 associated with each one of the filter pots 14. In each of the cover elements 20, a lengthwise segment 28 of the fluid manifold 24 is configured as a single piece integrated with the corresponding cover element 20. Adjacent cover elements 20 and lengthwise segments 28 are each delimited from one another by upper-side indentations 48 of the housing upper part 18.
According to yet another embodiment depicted in
Number | Date | Country | Kind |
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10 2016 001 851.8 | Feb 2016 | DE | national |