Filter and Cyclone Filter System

Abstract

The invention relates to a filter (28) for removing particulate matter from a gaseous fluid (12) having a filter element (30) with a filter media (32) which is arranged in a ring-shaped fashion around the longitudinal axis (34) thereof and a pre-separator sleeve (40) which seats on the filter element (30) and which has several perforations (52). On an outside surface (42) of the pre-separator sleeve (40), there is arranged at least one guide vane (44) which extends radially outwards from the pre-separator sleeve (40). The guide vane (44) is wound around the pre-separator sleeve (40) in a helical fashion to thereby further increase the separating efficiency of the pre-separator sleeve (40). The invention further relates to a cyclone filter system with an aforesaid filter (28).

Claims

1. A filter (28) for removing particulate matter from a gaseous fluid (12) comprising: a filter element (30) with a filter media (32) which is arranged in a ring-shaped fashion around the longitudinal axis (34) thereof; and a pre-separator sleeve (40) which seats on the filter element (30) and which has several perforations (52), wherein on an outside surface (42) of the pre-separator sleeve (40), there is arranged at least one guide vane (44) which extends radially outwards from the pre-separator sleeve (40), wherein the guide vane (44) is wound around the pre-separator sleeve (40) in a helical fashion.

2. The filter according to claim 1, wherein the pre-separator sleeve (40) has a non-perforated first end portion (46) which serves as a baffle for the gaseous fluid (12).

3. The filter according to claim 2, wherein the non-perforated first end portion (46) of the pre-separator sleeve (40) has a circular flow locking means for preventing a circulating flow of the gaseous fluid (12) in a circumferential direction around the pre-separator sleeve (40).

4. The filter according to claim 3, wherein the flow-locking means is formed by an arcuate branch of the helical guide vane (44).

5. The filter according to claim 1, wherein the helical guide vane (44) in a longitudinal direction of the pre-separator sleeve (40), extends over a major portion of the total length (66) of the pre-separator sleeve (40).

6. The filter according to claim 1, wherein the helical guide vane (44), in the longitudinal direction, extends to or essentially to a reinforcement ring (60) of the pre-separator sleeve (40).

7. The filter according to claim 6, wherein the reinforcement ring (60) extends in a radial direction away from the pre separator sleeve (40) at a second end portion (48) thereof.

8. The filter according to claim 7, wherein the helical guide vane (44) has a base section (44a) extending away from the pre-separator sleeve (40) in a radial direction and an angled end section (44b) which is joined to the base section (44a).

9. The filter according to claim 8, wherein the end section (44b) is arranged parallel or essentially parallel to an outside surface (42) of the pre-separator sleeve (40).

10. The filter according to claim 8, wherein at least part of the perforations (52) of the pre-separator sleeve (40) are covered by the helical guide vane (44) in a radial direction.

11. The filter according to claim 1, wherein the helical guide vane (44) has a radial extension which is at least 10% of the outer diameter (54) of the pre-separator sleeve (40).

12. A cyclone filter system (10) for removing particulate matter from a gaseous fluid (12) comprising a filter housing (14) having a fluid inlet port (18) and a fluid outlet port (20); and a filter (28) according to claim 1 positioned inside the filter housing (14).

13. The cyclone filter system according to claim 12, wherein the fluid inlet port (18) is arranged laterally on a side wall of the filter housing (14) to allow for a radial or tangential flow of the gaseous fluid to the pre-separator sleeve (40).

14. The cyclone filter system according to claim 12, wherein the outlet port (20) of the filter housing (14) is arranged axially on an first end (22) of the filter housing (14) and which is preferably positioned adjacent to the fluid inlet port (18) thereof.

15. The cyclone filter system according to claim 12, wherein the filter housing (14) forms a dirt chamber (26) for particulate matter separated from the gaseous fluid (12) which, preferably, extends in a radial direction thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference numerals characterize the same or similar parts throughout the several views, and wherein:

[0019] FIG. 1 is a sectional view of a cyclone filter system with a filter configured in accordance with the present invention;

[0020] FIG. 2 is a perspective view of the filter of the filter system of FIG. 1;

[0021] FIG. 3 is a different perspective view of the filter of FIG. 2;

[0022] FIG. 4 is a front elevation of a pre-separator sleeve of the filter of FIG. 2

[0023] FIG. 5 is a perspective view of an alternative embodiment of a pre-separator sleeve for the filter of FIG. 1;

[0024] FIG. 6 is a perspective view of a further embodiment of a filter; and

[0025] FIG. 7 is a sectional view of a further embodiment of a filter system with the filter of FIG. 6.

DESCRIPTION OF THE DISCLOSURE

[0026] FIG. 1 shows a cyclone filter system 10 for cleaning a gaseous fluid 12, i.e. the combustion air that is fed to the cylinders of a combustion engine (not shown). The filter system 10 has a filter housing 14 embodied as a cyclone that is hollow and cylindrical. The filter housing 14 has a longitudinal axis 16, a lateral inlet port 18 over which the uncleaned gaseous fluid 12 flows radially or tangentially into the housing 14 and an axial fluid outlet port 20 located centrally at a one end 22 of the housing 14. The filter housing 14, preferably at its other end 24, forms a dirt chamber 26 for particulate matter or water droplets separated from the gaseous fluid 12 which can, in particular extend in a radial direction thereof.

[0027] There is a filter 28 arranged inside the filter housing 14. The filter 28 comprises a hollow cylindrical filter element 30 with a filter medium 32 arranged in a circular fashion around the longitudinal axis 34 of the filter element 30. The filter medium 32 may be starpleated in order to maximize the effective surface area thereof. Also, the filter medium 32 may be disposed between two end plates 36. There may be provided a grid-shaped support tube 38 for a radial support of the filter medium 32. The filter medium 32 is flowed through radially from the outside to the inside by the gaseous fluid 12 to be filtered.

[0028] The filter element 30 is seated within a hollow cylindrical pre-separator sleeve 40 which, on its outside surface 42 has at least one guide vane 44 for the gaseous fluid 12 which extends from the pre-separator sleeve 40 in a radial outward direction.

[0029] The pre-separator sleeve 40 extends from a first end portion 46 to a second end portion 48 thereof. The first end portion 46 serves as a baffle for the gaseous fluid. The first end portion 46 is non-perforated. The non-perforated first end portion 46 is located right next to the fluid inlet port 18 of the filter housing 14 such that an inflow of the gaseous fluid 12 is fed right against the said non-perforated end portion 46. Bordering the non-perforated end portion 46 in an axial direction, the pre-separator shows a longitudinal middle portion or segment 50 with a multitude of perforations 52. The perforations 52 allow for a radial entry of the gaseous fluid 12 into the filter 28.

[0030] The pre-separator sleeve 40 has a smaller outer diameter 54 than the inner diameter 56 of the filter housing 14, so that an annular space 58 is formed between the wall of the housing 14 and the pre-separator sleeve 40 in which the inflowing, uncleaned gaseous fluid 12 can disperse. The pre-separator sleeve 40 is preferably made of plastic, particularly injection-molded thermoplastic plastic, or metal. The pre-separator sleeve 40 may have at least one stiffening or reinforcement ring 60 which is preferably located at the second end portion 48 located opposite the said non-perforated end portion 46. The at least one reinforcement ring 60 extends in a radial direction away from the pre-separator sleeve 40 and allows for a minimal material thickness of said sleeve.

[0031] The gas entering the annular space 58 undergoes swirling supported by the guide vane 44 and undergoes deflection in a radial direction towards the inside 62 of the filter element, whereby coarse contaminants that are being carried along in the gaseous fluid, for example dirt particles or water droplets, are thrown tangentially outward and thus separated from the gaseous fluid 12 flow.

[0032] As the gaseous fluid 12 continues to flow, it enters the filter 28 via the perforations 52 provided in the pre-separator sleeve 40. After passing the filter medium 32 of the filter element, the thus filtered gaseous fluid 12 is then discharged axially from the inner space 62 of the filter element 30 via an axial outlet 64 of the filter fluidly connected to the axial outlet port 20 of the filter housing 14. It needs to be noted that there may be provided a further inner annular space between the pre-separator sleeve 40 and the filter medium 32 of the filter element 30 on the raw side of the filter element 32. In other words, the pre-separator sleeve dos not necessarily need to directly contact the filter medium in a radial direction.

[0033] FIGS. 2 and 3 show different perspective representations of the filter 28 from the exemplary embodiment according to FIG. 1. The guide vane 44 of the pre-separator sleeve 40 is wound around the pre-separator sleeve 40 and its longitudinal axis 34 in a helical fashion. The helical guide vane preferably has no interruptions, in particular gaps or recesses. The helical guide vane 44 can extend from the baffle or non-perforated first end portion 46 of the pre-separator sleeve 40 over a major portion of the total length 66 of the pre-separator sleeve 40.

[0034] Further, in the present embodiment shown in FIGS. 1 to 3, the helical guide vane 44 forms more than one full turn or winding on the pre-separator sleeve. It is needless to say, that the guide vane 44 may even form two full turns or windings on the pre-separator sleeve, in particular depending on the total length of the sleeve and the expected maximal flow of the gaseous fluid during use of the filter. The helical guide vane 44, in the longitudinal direction, extends to or essentially to the reinforcement ring 60 of the pre-separator sleeve 40 which extends in a radial direction away from the pre-separator sleeve 40.

[0035] As can be best seen from the individual depiction of the pre-separator sleeve 40 shown in FIG. 4, the helical guide vane 44 has a radial extension which is at least 10% of the outer diameter 54 of the pre-separator sleeve 40.

[0036] FIG. 5 shows a modified embodiment of a pre-separator sleeve 40 for the filter 28 shown in FIGS. 1 to 3 which is provided with an additional flow locking means 68 for preventing a circulating flow of the gaseous fluid in a circumferential direction of the non-perforated first end portion 46 of the pre-separator sleeve 40. The flow-locking means 68 may be preferably formed by a, in particular arcuate, branch of the helical guide vane 44.

[0037] FIG. 6 shows a modified embodiment of the filter 28 with the helical guide vane 28 having a base section 44a extending away from the pre-separator sleeve 40 in a radial direction and an angled end section 44b which is directly joined to the base section 44a. The angled end section 44b extends in an axial direction and is aligned in a parallel or essentially parallel fashion with respect to the outside surface 42 of the pre-separator sleeve 40.

[0038] FIG. 7 shows a sectional view of a further cyclone filter system 10 with a housing 14 and the filter 28 of FIG. 6 arranged therein. The flow openings or perforations 52 of the pre-separator sleeve 40 are arranged one behind the other in a helical fashion which corresponds to the three dimensional course of the helical guide vane 44. The flow openings 52 are covered by the helical guide vane 44 in a radial direction. The helical guide vane thus forms an outer radial side cover for the perforations 52 of the pre-separator sleeve 40. Of note, there is a common helical inlet or opening 70 formed in between the angled end section 44b of the helical guide vane 44 and the outside surface 42 of the pre-separator sleeve 40. In the embodiment shown, the gaseous fluid 12 is not only swirled when flowing from the inlet port 18 of the filter housing around the filter 28 but is further deflected in an axial direction before entering the helical inlet opening 70 and reaching the perforations 52 of the pre-separator sleeve 40. This allows for a further improvement of the pre-separating efficiency of the cyclone filter system 10 and filter 28, respectively.