WO2013010818A1

WO2013010818A1 - Fluid-filtering arrangement and filtering method

Info

Publication number: WO2013010818A1
Application number: PCT/EP2012/063253
Authority: WO
Inventors: Wolfgang Heikamp; Carsten Schippers
Original assignee: Mann+Hummel Gmbh
Priority date: 2011-07-21
Filing date: 2012-07-06
Publication date: 2013-01-24
Also published as: DE102011108061A1; DE112012003054A5

Abstract

The invention describes a fluid-filtering arrangement (1) with a housing (2), comprising a front plate (10) and a filter element (4) with a main separator (7) and, arranged concentrically thereto, a secondary separator (8), which separators are arranged in succession in a direction of flow. A preliminary separator (15) is arranged upstream of the main separator (7) in the direction of flow. In a method performed in particular to remove oil from compressed air, the fluid is filtered in three stages in a fluid-filtering arrangement (1). The fluid flows first through a preliminary separator (15), then a main separator (7) and, finally, a secondary separator (8).

Description

Fluid filter assembly and filtering method

Technical area

The present invention relates to a fluid filter assembly, such as for de-oiling compressed air, and a method for filtering a fluid, in particular for de-oiling compressed air.

State of the art

Fluid filters generally serve to separate a fluid from certain substances that are present in the fluid but not desired. Thus, fluid filters may e.g. be used for the Entöllung of compressed air. Such fluid filter arrangements are also referred to as air exhaust boxes, which serve for the de-oiling of compressed air, which is generated by oil-injecting compressors. The compressed air generated by these compressors is therefore oil-contaminated and must be removed prior to use, e.g. the feed into a compressed air network, be de-oiled with the aid of air de-oiling elements. Such Luftentölelemente with its own pressure-resistant housing are fluid filter assemblies, which are called Luftentölboxen.

A de-oiling of the compressed air is achieved by the fact that the air-oil mixture in mist form must flow through a main separator and a downstream secondary separator. The fine oil aerosol is brought together in the main separator to larger droplets, which are finally collected in the Nachabscheider and abdrainiert.

EP 2 105 184 A2 illustrates a filter with a filter pot and a filter insert accommodated therein, as well as an end disk arranged on the end side of the filter insert with a pre-separator.

It is desirable to improve filter performance, especially when used as an air cleaner, of compressed air.

Disclosure of the invention

It is therefore an object of the present invention to provide an improved fluid filter assembly. This object is achieved by a fluid filter arrangement having a particularly pressure-resistant housing, comprising an end disk and a two-stage filter element a main separator and a concentrically arranged Nachabscheider, which are connected in succession in a flow direction solved. A third stage is formed by a pre-separator, which is arranged within the housing between the end plate and the filter element in series with the main separator and the post-separator.

The object is also achieved by a method for filtering fluid, in particular for de-oiling compressed air. In this case, the fluid is filtered in three stages in a fluid filter arrangement. The fluid flows through one behind the other first a pre-separator, then a main separator and finally a Nachabscheider. In particular, the method is carried out using a filter arrangement as described here and below.

By means of the additional pre-separation in an inlet region of the fluid filter arrangement, an oil supply on the main separator can be reduced.

This third upstream separation stage can reduce pressure loss in the downstream stages. Thus, the total pressure loss of the fluid filter assembly can be reduced.

This also makes it possible to reduce the operating costs of the compressor.

It is possible to extend the service life of the filter element in this way.

In one embodiment, it is provided that the main separator and the Nachabscheider are radially spaced by a gap.

A simple structure can be achieved if the main separator and the Nachabscheider are connected via slices.

In a further embodiment, the pre-separator may be arranged in a gap between the end disk, with which the housing is closed, and the filter element. Thus, the third stage can be arranged in the inlet region of the filter arrangement, whereby an overall structure is increased only insignificantly.

In yet another embodiment, the pre-separator may comprise guiding elements. This can be effected by means of a deflection of the fluid flow, that the substances to be deposited can be separated by inertia alone.

It can be provided that each guide element has an inlet section and an outlet section connected thereto. The outlet section can be arranged in a preferred embodiment to the inlet section at a substantially right angle. The pre-separator is preferably designed in the manner of a cyclone separator for performing a cyclone pre-filtering. In a further embodiment, the pre-separator may be a separate component to be inserted or inserted. It can be made of plastic. Of course, a production of a metallic material is possible. Combinations of different materials are also conceivable. In an alternative embodiment, the pre-separator may be formed integrally with the end disk.

In a preferred embodiment, the fluid filter assembly may be an air exhaust box for de-oiling compressed air.

Further possible implementations of the invention also include not explicitly mentioned combinations of features or embodiments of the filter element or of the fluid filter arrangement described above or below with regard to the exemplary embodiments. The skilled person will also add individual aspects as improvements or additions to the respective basic form of the invention.

Further embodiments of the invention are the subject of the dependent claims and the embodiments of the invention described below. Furthermore, the invention will be explained in more detail by means of embodiments with reference to the accompanying figures. Brief description of the drawings

It shows:

1 is a schematic partial cross-sectional view of an embodiment of a

Fluid filter arrangement;

Fig. 2 is an enlarged schematic view of the section II of

Embodiment of Fig. 1; and Fig. 3 is an enlarged schematic view of section II of the embodiment of Fig. 1 with a further embodiment of a

Pre-separator.

In the figures, the same reference numerals designate the same or functionally identical elements, unless indicated otherwise.

Embodiment (s) of the invention

In Figure 1, a fluid filter assembly 1 is shown, which is also referred to as Luftentölbox and used for the de-oiling of compressed air. The fluid filter assembly 1 comprises a housing 2, which serves as a receptacle for a filter element 4. The housing 2 has a front side 3 on a side lying in the figure 1, which is closed by an end plate 10. The other, in the figure 1 overhead page is closed. The housing 2 is e.g. circular cylindrical trained. It can e.g. be made of a metallic material, a suitable plastic or a combination thereof. It can also be pressure safe.

The filter element 4 is disposed within the housing 2 and here also designed circular cylindrical. Other forms are of course conceivable. The filter element 4 has two concentrically arranged separation stages, of which a main separator 7 is arranged on the outside and a Nachabscheider 8 inside. The main separator 7 is for example an air de-oiling element. It is made of a suitable filter material. Between the main separator 7 and the secondary separator 8, which is likewise constructed, for example, as a de-oiling element, there is a gap 9, through which the main separator 7 and the secondary separator 8 are radially separated from one another. The Nachabscheider 8 also has a suitable filter material. Furthermore, the filter element 4, a support member 6, which is fluid-permeable and designed, for example, in the manner of a grid or a broken or perforated rod. The support member 6 is disposed within the Nachabscheiders 8 and defines an interior of the filter element 4. Plastic material is used as the material of the support body 6, for example. The support body 6 may also consist of a metallic material. Of course, combinations of metal and plastic or other materials are possible. On the support body 6 of the Nachabscheider 8, for example, as a kind of filter roll applied. The filter element 4 is closed at its upper end, which faces the closed side of the housing 2, with a disc 21 not designated in detail. At its lower end, a disc 22 is also arranged with a central opening, wherein this opening is surrounded by a collar or neck 5, which faces the end face 3 of the housing 2. These disks 21, 22 are also used to support support body 6, main separator 7 and Nachabscheider 8. By the support of the support body 6, the main separator 7 and Nachabscheider 8 in the discs 21, 22 of the gap 9 is fixed.

On the closed side of the housing 2, the filter element 4 is supported by a spring not described in detail. At the end face 3 of the housing 2, the neck 5 of the filter element 4 is connected to a nozzle 1 1 of the end plate 10. In this case, the neck 5 surrounds the neck 1 1 fluid-tight, wherein this compound is acted upon by the spring axially with a force. This compound can e.g. also be made by means of an adhesive bond.

The end plate 10 is connected in a manner not further explained with the housing 2 pressure-resistant. The nozzle 1 1 of the end plate 10 surrounds a fluid outlet 12, which communicates with the interior of the filter element 4. Concentrically with the fluid outlet opening 12, fluid inlet openings 13 are arranged, which communicate with an inlet area 14. The inlet portion 14 is a circumferential space which is disposed between the lower end of the filter element 4, which is provided with the lower disc 22 with the neck 5, and the inner side of the end plate 10. This intermediate space 14 is bounded on its outer edge by the housing 2 and communicates with a cylindrical space which is arranged between the outside of the main separator 7 and the inside of the housing 2. Within the inlet region 14, a pre-separator 15 is arranged, which will be described in more detail below. The pre-separator 15, main separator 7 and Nachabscheider 8 are connected in series in the flow direction.

FIG. 2 shows an enlarged schematic view of section II of the embodiment according to FIG. 1. Here, the inlet region 14 with the pre-separator 15 is shown enlarged. A flow direction 20 is indicated by an arrow.

The pre-separator 15 in the inlet region 14 is schematically indicated in this embodiment by a cross symbol. The pre-separator 15 is flowed through by the fluid, in particular compressed air, and carries out a pre-separation of substances, in particular of oil, from the fluid. In order for a deposition of these substances is reduced to the main separator 7. In addition, this third upstream separator stage before the other two separator stages, namely the main separator 7 and the Nachabscheider 8, reduces pressure drop in these two further separator stages. Thus, a total pressure loss of the fluid filter assembly 1 is also reduced. At the same time, a service life of the filter element 4 lengthens.

The pre-separator 15 may e.g. a separate component, which can be inserted into the inlet region 14 between the inside of the end plate 10 and the underside of the filter element 4. This separate component can also be attached, for example, to the underside of the filter element 4 or / and the inside of the end plate 10, e.g. by inserting into a dedicated receptacle. An attachment may also be possible, e.g. by clipping. In another embodiment, the pre-separator 15 is integrally formed with the end plate 10. It is also conceivable that the pre-separator 15 is attached to the underside of the filter element 4, e.g. integral with the lower plate 22 is formed.

The pre-separator 15 directs the fluid flowing through the inlet openings 13 by deflecting at certain sections, for example initially radially outward and then axially upwards into the space between the main separator 7 and the housing 2. A swirling is also possible. For example, the pre-separator 15 may have a type of vane shape, which initially directs the inflowing fluid radially outwards, then into Circumferential direction and then deflects in the axial direction of the housing 2. In this case, an acceleration of the fluid can take place. This causes a separation of entrained in the fluid substances, such as oil in compressed air, for example, by gravity and inertia. In the embodiment of the pre-separator, one can also speak of a cyclone separator. For example, the shape of the separator blades 15 may be configured for cyclone filtering.

FIG. 3 shows the enlarged schematic view of section II of the embodiment according to FIG. 1 with a further exemplary embodiment of the pre-separator 15.

In this embodiment, the pre-separator 15 on guide elements 16, of which only one is shown schematically. These baffles 16 are located on the periphery of the inlet area 14, e.g. arranged distributed on the inside of the end plate 10. In this embodiment, the guide elements 16 of the pre-separator 15 are formed as guide vanes. Each guide element 16 has an inlet section 17, a connecting section 18 and an outlet section 19. The inlet section 17 is substantially parallel to a radial direction. The outlet section 19 is bent or angled away from this radial direction toward the interior of the housing 2. For example, it may be at an angle in the range of e.g. 90 ° ± 15 ... 45 ° to the inlet portion 17 may be arranged. Of course, other angles are conceivable. The outlet section 18 may also have several different angles in a row. Entry portion 17 and exit portion 19 are connected by a connecting portion 18, which may be formed angular or rounded. Twists of these vanes 16 are of course possible.

The pre-separator 15 may be formed of a plastic. It is also conceivable that it can be made of metal. Of course, combinations of materials are also possible.

The fluid filter assembly 1 allows filtering of fluid, in particular a de-oiling of compressed air, wherein first the fluid to be cleaned through the fluid inlet openings 13 of the end plate 10 of the housing 2 in the inlet region 14 between the lower disc 22 of the filter element 4 and the inside of the end plate 10 flows , First, the fluid to be cleaned flows radially, as indicated by an arrow in the flow direction 20 in FIGS. 2 and 3, through the intermediate space 14 into the preseparator 15, in particular in the guide elements 16 of the pre-separator. In this case, a pre-separation of substances by inertia occurs when the fluid is deflected by the pre-separator 15. A deflection of the fluid flow then takes place directly from the radial in the axial direction and / or from the radial in a spriral-shaped direction around the central axis of the housing 2 around. Thereafter, the fluid flows through the downstream main separator 7, the intermediate space 9, through the Nachabscheider 8 in the interior of the support body 6, from which it exits through the fluid outlet 12 again.

Thus, with the fluid filter assembly 1 and the implementation of a method for filtering fluid, in particular a de-oiling of compressed air, allows. The fluid is de-oiled in three stages, wherein the fluid first flows through the pre-separator 15, then the main separator 7 and finally the Nachabscheider 8.

Claims

claims

1 . Fluid filter arrangement (1) having a housing (2), comprising an end disc (10) and a two-stage filter element (4) with a main separator (7) and a post-separator (8) arranged concentrically in a flow direction, wherein a third stage is formed by a pre-separator (15) disposed within the housing (2) between the end plate (10) and the filter element (4) in series with the main separator (7) and the post-separator (8).

Second fluid filter assembly (1) according to claim 1, wherein the main separator (7) and the Nachabscheider (8) are radially spaced by a gap (9).

3. fluid filter assembly (1) according to claim 1 or 2, wherein the main separator (7) and the Nachabscheider (8) by means of discs (21, 22) are connected.

4. fluid filter assembly (1) according to any one of claims 1-3, wherein the pre-separator (15) in an intermediate space (14) between the end plate (10), with which the housing (2) is closed, and the filter element (4) is.

5. fluid filter assembly (1) according to claim 4, wherein the pre-separator (15) has guide elements (16).

6. fluid filter assembly (1) according to claim 5, wherein each guide element (16) has an inlet portion (17) and an associated outlet portion (19).

7. The fluid filter assembly (1) according to claim 6, wherein the outlet portion (19) is arranged to the inlet portion (17) at a substantially right angle.

8. fluid filter assembly (1) according to any one of claims 1 to 7, wherein the pre-separator (15) is a separate component.

9. fluid filter arrangement (1) according to one of claims 1 to 7, wherein the pre-separator (15) is formed integrally with the end plate (10).

10. fluid filter assembly (1) according to any one of claims 1 to 9, wherein the fluid filter assembly (1) is a Luftentölbox for the de-oiling of compressed air.

1 1. Method for filtering fluid, in particular for de-oiling compressed air, wherein the fluid in a fluid filter assembly (1) is filtered in three stages, wherein the fluid first flows through a pre-separator (15), then a main separator (7) and finally a Nachabscheider (8) in a row ,