EP0122795A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Filter for removing particulates suspended in a fluid, e.g. gaseous medium
Assignee: Garrett Corp
•
Filing: 1984-04-13
•
Granted: —
•
Expires: 2004-04-13
Abstract
Abstract A high-speed rotary filter device comprises a tubular housing (24) containing a bladed rotor (22). The rotor carries inducer blades (30) in a radial outflow configuration, driving blades (32) extending axially above the length of the rotor, and exducer blades (36), and is driven by a shaft at high speed to cause an air stream to be drawn into the housing inlet end (22) by the inducer blades and to travel axially along the housing between the driving blades (32) whilst being forced to swirl around the rotor body (34). Particles suspended in the airstream migrate centrifugally to the internal surface of the housing wall, where they are collected in circumferential grooves (100, 102, 104) and escape from the housing through passages (110, 200, 212) in the housing wall. The filtered air stream is discharged by the exducer blades (36) through the outlet end of the housing via a scroll (50). In a modification (Figure 4) the inducer blades (130) are of axial-flow configuration, and act as a turbine wheel to drive the rotor under a gas pressure differential. In another modification (Figure 7) the inducer blades (172) are of mixed flow configuration. Afurther modification (Figure 14) involves a porous shroud (310) in the form of a helical winding of spaced turns of wire wound around the tips of the rotor driving blades (320) to minimise secondary swirl. In an alternative design (Figure 13) to minimise secondary swirl a rotor (232) having a separator portion (23) with no driving blades is provided. The filter devices are capable of filtering out particles ranging from 2 mm diameter down to 2 microns diameter from a gas stream without clogging, and can also be used for filtering liquids.
Inventors
- 👤 Lee R. Woodworth
- 👤 Beb H. Rowlett
- 👤 Lorant Nagyszalanczy
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 19:32
CPC Classifications
F; F02; F02M; F02M35/00; F02M35/02; F02M35/022; B; B01; B01D; B01D21/00; B01D21/26; B01D21/262; B01D45/00; B01D45/12; B01D45/14; F01; F01N; F01N3/00; F01N3/02; F01N3/037; F02M35/08; F01N2290/00; F01N2290/02; F01N2290/04; F01N2290/06; F02B; F02B1/00; F02B1/02; F02B1/04; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 59
Claim 1
Independent Claim
174 words
A filter device (20,120) for removing particles from a fluid medium,which comprises a housing (24,122,182,234) having an inlet end (40,132,184,242) affording a fluid inlet and an outlet end (50,140,252) affording a fluid outlet, a rotationally-driven rotor (22,124,190,232,300) mounted in the housing and defining an annular-section space between the body (34,144,180,232) of the rotor and the circumferential wall of the housing, along which space a fluid stream to be filtered flows in use in the axial direction from the inlet to the outlet, and means for driving the rotor at high rotational speed to cause the fluid stream to swirl at high speed around the body of the rotor in the annular-section space so as to subject particles in the fluid stream to centrifugal acceleration causing them to migrate to the outer portion of the space immediately adjacent to the circumferential wall of the housing, and in which the housing is provided with means (100,102,104,110,160,162,164,200,210) for removing the migrated particles from the said outer portion of the annular-section space to a location outside the housing.
Claim 2
Dependent Claim
174 words
A filter device (20,120) for removing particles from a fluid medium,which comprises a housing (24,122,182,234) having an inlet end (40,132,184,242) affording a fluid inlet and an outlet end (50,140,252) affording a fluid outlet, a rotationally-driven rotor (22,124,190,232,300) mounted in the housing and defining an annular-section space between the body (34,144,180,232) of the rotor and the circumferential wall of the housing, along which space a fluid stream to be filtered flows in use in the axial direction from the inlet to the outlet, and means for driving the rotor at high rotational speed to cause the fluid stream to swirl at high speed around the body of the rotor in the annular-section space so as to subject particles in the fluid stream to centrifugal acceleration causing them to migrate to the outer portion of the space immediately adjacent to the circumferential wall of the housing, and in which the housing is provided with means (100,102,104,110,160,162,164,200,210) for removing the migrated particles from the said outer portion of the annular-section space to a location outside the housing.
Claim 3
Dependent Claim
22 words
A filter device as claimed in Claim l,which includes driving means (70,260) mechanically connected to therotor (22,232) for rotationally driving the rotor.
Claim 4
Dependent Claim
20 words
. 3. A filter device as claimed in Claim 2, in which the driving means is an electric motor (260).
Claim 5
Dependent Claim
36 words
4 . A filter device as claimed in Claim 2,in which the driving means comprises a turbine wheel (130) driven by a fluid pressure differential between the fluid inlet and the fluid outlet of the housing.
Claim 6
Dependent Claim
42 words
A filter device as claimed in any one of the preceding claims, in which the rotor carries a set of inducer blades (30,172,270) located adjacent to the fluid inlet,by which rotational energy is imparted to the fluid stream entering the annular-section space.
Claim 7
Dependent Claim
47 words
A filter device as claimed in Claims 2 and 5 in which the driving of the rotor causes the - inducer blades (30,172,270) to draw the fluid stream into the housing through the air inlet, and to impart dynamic pressure to the fluid stream entering the housing.
Claim 8
Dependent Claim
34 words
A filter device as claimed in Claims 4 and 5, in which the set of inducer blades (130) constitutes the turbine wheel by which the rotor is driven rotationally under the fluid pressure differential.
Claim 9
Dependent Claim
22 words
A filter device as claimed in any one of Claims 5-7, in which the inducer blades (13-0) have an axial flow configuration.
Claim 10
Dependent Claim
21 words
A filter device as claimed in any one of Claims 5-7,in which the inducer blades (30) have a radial outflow configuration.
Claim 11
Dependent Claim
38 words
A filter device as claimed in any one of Claims 5 to 7, in which the inducer blades (172,270) have a configuration establishing a combination of axial flow and radial outflow in the fluid stream passing through them.
Claim 12
Dependent Claim
44 words
A filter device as claimed in any one of Claims 5 to 10, in which the rotor carries a set of exducer blades (36,136,176,280) located adjacent to the fluid outlet by which rotational energy is removed from the fluid stream leaving the annular-section space.
Claim 13
Dependent Claim
26 words
A filter device as claimed in Claims 6 and 11, in which the exducer blades remove dynamic pressure from the fluid stream leaving the annular-section space.
Claim 14
Dependent Claim
53 words
A filter device as claimed in any one of the preceding claims,in which the rotor (22,124,190,320) carries a set of driving blades (32,126,174) extending along its axial length and projecting outwardly within the annular-section space, the radially-outer edges of the driving blades lying in close proximity to the circumferential wall of the housing.
Claim 15
Dependent Claim
56 words
A filter device as claimed in Claim 13 when dependent on Claim 11 or Claim 12, in which the driving blades (32,126,174) are situated in.a separator portion of the rotor disposed between the inducer blades (30,130,172, 270) and the exducer blades (36,136,176,280), the inducer blades leading the fluid stream into the spaces between the driving blades.
Claim 16
Dependent Claim
28 words
A filter device as claimed in Claim 13 or Claim 14,in which the driving blades (32,126,174) extend longitudinally parallel to the rotor axis with their widths projecting radially.
Claim 17
Dependent Claim
49 words
A filter device as claimed in any one of Claims 13-15, in which the portion of the interior of the housing (24,122) adjacent to the driving blades is cylindrical and in which the tips of the driving blades (32,126) are of uniform radius along the lengths of the blades.
Claim 18
Dependent Claim
88 words
A filter device as claimed in any one of Claims 13-15 in which the portion of the interior of - the housing (182) adjacent to the driving blades is of progressively-increasing diameter along its length in the direction from its inlet end towards its outlet end, and in which the radially-outer edges of the driving blades (174) are of correspondingly-increasing radius along the lengths of the blades so that the said blade edges lie at a constant distance from the housing wall along the lengths of the blades.
Claim 19
Dependent Claim
29 words
A filter device as claimed in any one of Claims 1-17, including a porous shroud means (310) within the annular-section space for minimising secondary flow swirl in said space.
Claim 20
Dependent Claim
30 words
A filter device as claimed in Claim 18 in which the porous shroud means (310) surrounds and is carried by the rotor (300) in close proximity to the housing wall.
Claim 21
Dependent Claim
41 words
A filter device as claimed in any one of Claims 13-17,including a porous shroud means (310) surrounding the rotor (300) close to radially-outer edges of the driving blades (320) and carried by the rotor for rotation therewith in the annular-section space.
Claim 22
Dependent Claim
29 words
A filter device as claimed in any one of Claims 18-20,in which the porous shroud means (310) comprises a helical winding of a plurality of axially-spaced turns of wire.
Claim 23
Dependent Claim
41 words
A filter device as claimed in Claim 21,in . which the relationship between the diameter of the wire and the distance between each successive turn of wire is such that the porosity of the shroud means is between 5% and 30%.
Claim 24
Dependent Claim
35 words
A filter device as claimed in Claim 20 in combination with either Claim 21 or Claim 22, in which the wire winding (310) is wrapped around the axially-extending radially-outer edges of the driving blades (320).
Claim 25
Dependent Claim
20 words
A filter device as claimed in Claim 23 in which the wire winding (310) is pre-stressed around the driving blades.
Claim 26
Dependent Claim
27 words
A filter device as claimed in Claim 18 or Claim 19 or Claim 20, in which the porous shroud means is a mesh having a preselected porosity.
Claim 27
Dependent Claim
26 words
A filter device as claimed in Claims 20 and 25, in which the mesh is wrapped around the axially-extending radially-outer edges of the driving blades (320).
Claim 28
Dependent Claim
26 words
A filter device as claimed in Claim 18 or Claim 19 or Claim 20, in which the porous shroud means is made of perforated sheet metal.
Claim 29
Dependent Claim
36 words
A filter device as claimed in any one of Claims 18-27, in which the porous shroud means (310) does not substantially impede the centrifugal migration of said particles to the radially-outer portion of the annular-section space.
Claim 30
Dependent Claim
29 words
A filter device as claimed in any one of Claims 18-28,in which the porous shroud means (310) is utilised to minimise the breakup of large particles into smaller particles.
Claim 31
Dependent Claim
52 words
a filter device as claimed in any one of Claims 1-12, in which the rotor body (232) has a smooth bladeless surface portion (290) for minimising secondary flow swirl in the device , the said annular-section space being defined between the smooth surface portion and the circumferential wall of the housing (234).
Claim 32
Dependent Claim
22 words
A filter device as claimed in Claim 30, in which the smooth surface portion (290) is specifically configured to minimise secondary swirl.
Claim 33
Dependent Claim
38 words
A filter device as claimed in Claim 30 or Claim 31, in which the said smooth surface portion (290) is of smaller diameter near the outlet end of the housing (234) than it is near the inlet end.
Claim 34
Dependent Claim
52 words
33 A filter device as claimed in any one of Claims 5-12 in combination with any one of Claims 30 to 32, in which the smooth bladeless surface portion (290) of the rotor body (232) extends between the portion carrying the inducer blades (270) and the portion carrying the exducer blades (280).
Claim 35
Dependent Claim
75 words
A filter device as claimed in any one of the preceding claims, in which the said means for removing the migrated particles comprises at least one axial groove formed in the internal surface of the circumferential wall of the housing (24, etc), and at least one aperture located in the axial groove and extending through the housing wall to allow the escape of the migrated particles from the interior to the exterior of the housing.
Claim 36
Dependent Claim
68 words
A filter device as cla-imed in any one of Claims 1-33, in which the said means for removing the migrated particles comprises groove means (100,etc) formed in the internal surface of the circumferential wall of the housing (24 etc),in a plane orthogonal to the axis of the rotor (22, etc) and means (110,200,210) for transferring said particles collected in the groove means to a location outside the housing.
Claim 37
Dependent Claim
31 words
A filter device as claimed in Claim 35,in which said groove means comprises at least one groove (100,etc), extending around the entire circumference of the internal surface of the said wall.
Claim 38
Dependent Claim
22 words
A filter device as claimed in Claim 36,in which the or each groove (100,etc),is of uniform depth around the entire said circumference.
Claim 39
Dependent Claim
57 words
A filter device as claimed in any one of Claims 35-37, in which the said means for transferring particles collected in the groove means (100,etc), comprises a passage (110,200,210) formed in the wall of the housing (24, etc), and communicating with the groove means, the passage leading through the housing wall to the exterior of the housing.
Claim 40
Dependent Claim
48 words
A filter device as claimed in Claim 38 when dependent on Claim 36 or Claim 37, in which the said passage (110) tangentially intersects the groove (100,etc), to permit particles collected in and rotating around the groove to enter the passage and pass out of the housing therethrough..
Claim 41
Dependent Claim
53 words
A filter device as claimed in Claim 38 when dependent on Claim 36 or Claim 37, or in Claim 39, constructed and arranged so that a small portion of the fluid stream flowing in the annular-section space is diverted to flow outwardly through the said passage (110,280,210) to scavenge the collected particles therethrough.
Claim 42
Dependent Claim
26 words
A filter device as claimed in Claim 38 or 39 or 40, in which the said passage (110) is of uniform cross-sectional area along its length
Claim 43
Dependent Claim
64 words
A filter device as claimed in Claim 38 or Claim 39 or Claim 40,in each case when dependent on Claim 36, or on Claim 37, in which the said passage increases in cross section along its length in the direction towards the exterior of the housing (24) so as to act as an aerodynamic diffuser (210) for a scavenging fluid flow through the passage.
Claim 44
Dependent Claim
32 words
A filter device as claimed in any one of Claims 35-42,in which the groove means (100,etc),or the or each circumferential groove (100,etc), is provided with a plurality of the said passages (110,etc).
Claim 45
Dependent Claim
50 words
A filter device as claimed in Claim 38 when dependent on Claim 36, in which the depth of the or each groove (100,etc),increases along a portion of the circumference of the groove leading to the point of communication with the'passage (200) in the direction of particle rotation around the groove.
Claim 46
Dependent Claim
41 words
A filter device as claimed in Claim 44, wherein the passage (110.etc), comprises a passage extending through the wall of the housing (24) and being of increasing cross-sectional area ( at 210) in the direction towards the exterior of the housing.
Claim 47
Dependent Claim
70 words
A filter device as claimed in Claim 45,having at least one additional said passage (200) communicating with the groove (100, etc), at a different point in the circumference thereof and also extending through the housing wall to the exterior of the housing (24),the depth of the groove near the or each additional passage (200) similarly increasing along the portion of the groove circumference leading to the said point of communication.
Claim 48
Dependent Claim
90 words
A filter device as claimed in Claim 36 or Claim 37, or in any one of Claims 38 to 44 when dependent on Claim 36, having at least one additional circumferential groove (102,104, or 162, 164 or 296) formed in the interior surface of the housing wall in a location spaced axially downstream from the first groove (100,or 160 or 294) with respect to the flow direction of the fluid stream,and at least one additional said passage (110,etc), for transferring particles collected in the or each said additional groove means.
Claim 49
Dependent Claim
51 words
A filter device as claimed in Claim 47 in which the depth of the, or a least one additional groove (102 etc) is substantially less than that of the groove (100, 102 etc), next adjacent to it in the upstream direction with respect. to the flow direction of the fluid stream.
Claim 50
Dependent Claim
28 words
A filter device as claimed in any one of the preceding claims, constructed and arranged to remove both large and small particles from the fluid stream without clogging.
Claim 51
Dependent Claim
31 words
A filter device as claimed in any one of the preceding claims,constructed and arranged to be capable of removing substantially all particles greater in size than 2 microns from the airstream.
Claim 52
Independent Claim
102 words
A method of filtering small and large particles from a fluid medium,which comprises providing a rotor (22,124,190,232), rotatably mounted within a housing (24,122,182,234),causing a stream of the Fluid medium to be filtered to flow axially in the housing between the interior surface of the housing and the rotor whilst rotating the rotor . to cause the fluid stream to swirl around the rotor at high speed so that the particles are caused to migrate centrifugally outwards to a location immediately adjacent to the circumferential wall of the housing, and removing the migrated particles from that location to a location outside the housing.
Claim 53
Independent Claim
102 words
A method of filtering small and large particles from a fluid medium,which comprises providing a rotor (22,124,190,232), rotatably mounted within a housing (24,122,182,234),causing a stream of the Fluid medium to be filtered to flow axially in the housing between the interior surface of the housing and the rotor whilst rotating the rotor . to cause the fluid stream to swirl around the rotor at high speed so that the particles are caused to migrate centrifugally outwards to a location immediately adjacent to the circumferential wall of the housing, and removing the migrated particles from that location to a location outside the housing.
Claim 54
Dependent Claim
35 words
A method as claimed in Claim 51,in which comprises providing a turbine wheel (130) mechanically coupled to the rotor (124), and driving the turbine wheel by pressurised fluid to effect the rotation of the rotor.
Claim 55
Dependent Claim
31 words
A method as claimed in Claim 51 or Claim 52, in which the removal of the migrated particles is effected through an aperture (110,etc),formed in the circumferential wall of the housing.
Claim 56
Dependent Claim
69 words
A method as claimed in Claim 53,in which the internal surface of the housing wall has at least one groove (100,etc), formed therein, in which groove the migrated particles collect, the said aperture communicating with the groove.and which further comprises generating a scavenging fluid flow through the aperture to carry and remove the migrated particles, the scavenging flow being derived from the said fluid stream passing through the housing.
Claim 57
Independent Claim
50 words
A method as claimed in any one of Claims 51 to 54, in which in order to minimise the generation of secondary flow swirl in the annular space between the rotor body (34) and the circumferential wall of the housing (24). a porous shroud (310) is provided in said space.
Claim 58
Dependent Claim
91 words
A method as claimed in Claim 55,in which the rotor carries a set of axially-extending driving blades (320) which project outwardly to within a small distance from the circumferentiall wall of the housing (24), and in which in order to minimise the generation of secondary flow swirl in the portions of the said space lying between adjacent driving blades, the porous shroud (310) is wrapped around the rotor to be supported on the radially outer edges of the driving blades close to the housing wall, the shroud rotating with the rotor.
Claim 59
Independent Claim
36 words
A method as claimed in Clalim 56, in which the shroud (310) is composed of a helical winding of a plurality of axially-spaced turns of wire wound around the driving blades (320) of the rotor (300).
References Cited (Backward Citations)
DE570855C
Cited
US2441631A
Cited
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