US5489186A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Housing with recirculation control for use with banded axial-flow fans
Assignee: Airflow Research and Manufacturing Corp
•
Filing: 1995-02-15
•
Granted: 1996-02-06
•
Expires: 2015-02-15
Abstract
Abstract Stationary flow control vanes positioned to encounter and redirect recirculating airflow provide a surprising combination of efficiency, low noise, and manufacturability for shrouded, banded, axial fans that are positioned in a housing. Such fan and housing combinations reduce swirl in recirculating airflow, so that the airflow entering the fan (which includes the recirculating airflow) is more ordered and fan performance is improved. The invention is particularly suited for fans that draw airflow through an upstream heat exchanger. It can also be applied to fans that blow air through a downstream heat exchanger. The invention is also suited for ducted fans.
Inventors
- 👤 Martin G. Yapp
- 👤 Robert V. Houten
- 👤 Robert I. Hickey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:21
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/14; F01D5/141; F04; F04D; F04D19/00; F04D19/002; F04D29/00; F04D29/08; F04D29/16; F04D29/161; F04D29/164; F04D29/26; F04D29/32; F04D29/325; F04D29/326; F04D29/40; F04D29/52; F04D29/54; F04D29/541; F04D29/545
Claims Analysis
Total Claims: 45
Claim 1
Independent Claim
108 words
A fan and housing combination comprising a fan having a hub that rotates on an axis and blades extending outwardly from the hub to a circular band that connects the blade tips, the combination also comprising a housing surrounding the fan to control airflow the combination being characterized in that: a) a portion of the housing is positioned outward of the fan band and there are running clearances between the band and the housing such that recirculating airflow moves in a pathway between the fan and the housing; and b) stationary flow control vanes are connected to the housing in a position to encounter and redirect recirculating airflow.
Claim 2
Dependent Claim
108 words
A fan and housing combination comprising a fan having a hub that rotates on an axis and blades extending outwardly from the hub to a circular band that connects the blade tips, the combination also comprising a housing surrounding the fan to control airflow the combination being characterized in that: a) a portion of the housing is positioned outward of the fan band and there are running clearances between the band and the housing such that recirculating airflow moves in a pathway between the fan and the housing; and b) stationary flow control vanes are connected to the housing in a position to encounter and redirect recirculating airflow.
Claim 3
Dependent Claim
28 words
The fan and housing combination of claim 1 in which the fan is positioned downstream of a heat exchanger, whereby the fan draws air through the heat exchanger.
Claim 4
Dependent Claim
28 words
The fan and housing combination of claim 1 in which the housing is positioned upstream from a heat exchanger, whereby the fan pushes air through the heat exchanger.
Claim 5
Dependent Claim
15 words
The fan and housing combination of claim 1 in which the housing is a duct.
Claim 6
Dependent Claim
22 words
The fan and housing combination of claim 1 in which the housing and the vanes are a single injection molded plastic unit.
Claim 7
Dependent Claim
22 words
The fan and housing combination of claim 1 characterized by a radial fan-to-housing clearance of at least 0.25% of the fan diameter.
Claim 8
Dependent Claim
37 words
The fan and housing combination of claim 1 characterized in that an airflow recirculation pathway is formed between the fan band and the housing, and at least a portion of the vanes is positioned in the pathway.
Claim 9
Dependent Claim
34 words
The fan and housing combination of claim 1 or claim 7 in which the housing is characterized by a reduction in radius at a location rearward of the trailing edge of the fan band.
Claim 10
Dependent Claim
39 words
The fan and housing combination of claim 8 in which the pathway has an inlet formed between the fan band and the housing, and at least a portion of the vanes is positioned radially outward of the pathway inlet.
Claim 11
Dependent Claim
19 words
The fan and housing combination of claim 9 in which the radially innermost face of the vanes is rounded.
Claim 12
Dependent Claim
52 words
The fan and housing combination of claim 8 in which the housing radius reduction reduces the housing inner radius to R r , such that R r <C+R b , where R b is the outer radius of the trailing edge of the fan band, and C is the radial fan-to-housing clearance.
Claim 13
Dependent Claim
41 words
The fan and housing combination of claim 8 in which the housing radius reduction reduces the housing inner radius to a radius that is approximately equal to or less than the outer radius of the trailing edge of the fan band.
Claim 14
Dependent Claim
36 words
The fan and housing combination of claim 12 in which the housing radius reduction reduces the housing radius to a radius that is less than the outer radius of the trailing edge of the fan band.
Claim 15
Dependent Claim
27 words
The fan and housing combination of claim 8 in which the housing comprises a rearward housing segment extending from the radius reduction rearwardly to rearward housing terminus.
Claim 16
Dependent Claim
29 words
The fan and housing combination of claim 14 in which the housing comprises elongated motor supports which extend from the rearward housing segment to a centrally positioned motor mount.
Claim 17
Dependent Claim
29 words
The fan and housing combination of claim 14 in which, as the housing extends rearwardly from the location of the radius reduction, the inside diameter of the housing increases.
Claim 18
Dependent Claim
28 words
The fan and housing assembly of claim 16 in which, as the housing extends rearwardly from the location of the radius reduction, the thickness of the housing decreases.
Claim 19
Dependent Claim
50 words
The fan and housing combination of claim 8 in which an inlet to the pathway is formed between the housing and the trailing edge of the band, and the shroud comprises a portion which extends first rearwardly and then inwardly and forwardly, forming a pocket axially rearward of the inlet.
Claim 20
Dependent Claim
21 words
The fan and housing combination of clam 18 in which at least a portion of the vanes extends into the pocket.
Claim 21
Dependent Claim
21 words
The fan and housing combination of clam 18 in which at least a portion of the vanes extends into the pocket.
Claim 22
Dependent Claim
50 words
The fan and housing combination of claim 8 in which at least a portion of the vanes is axially rearward of the trailing edge of the band, and the vanes are characterized by a reduction in radius at a position axially rearward of the trailing edge of the fan band.
Claim 23
Dependent Claim
37 words
The fan and housing combination of claim 1 or claim 7 in which the recirculating airflow pathway includes an outlet formed between the housing and an outwardly flaring segment of the leading edge of the fan band.
Claim 24
Dependent Claim
26 words
The fan and housing combination of claim 1 in which the vanes are straight taken in a section in a plane normal to the fan axis.
Claim 25
Dependent Claim
26 words
The fan and housing combination of claim 22 in which the vanes are non-radial taken in a section in a plane normal to the fan axis.
Claim 26
Dependent Claim
26 words
The fan and housing combination of claim 22 in which the vanes are radial taken in a section in a plane normal to the fan axis.
Claim 27
Dependent Claim
26 words
The fan and housing combination of claim 1 in which the vanes are curved taken in a section in a plane normal to the fan axis.
Claim 28
Dependent Claim
24 words
The fan and housing combination of claim 1 characterized in that the vanes are positioned at least in part upstream of the fan band.
Claim 29
Dependent Claim
21 words
The fan and housing combination of claim 1 in which said vanes are all part a single injection molded plastic assembly.
Claim 30
Dependent Claim
27 words
The fan and housing combination of claim 1 in which said airflow recirculation pathway comprises a restriction upstream (from the perspective of recirculating airflow) of the vanes.
Claim 31
Dependent Claim
31 words
The fan and housing combination of claim 28 wherein the cross-sectional area of said pathway at said restriction is less than 1/2 the cross-sectional area of the outlet to said pathway.
Claim 32
Dependent Claim
28 words
The fan and housing combination of claim 28 wherein said band comprises a lip extending from the band to establish the restriction between the lip and the housing.
Claim 33
Dependent Claim
19 words
The fan and housing of claim 26 in which the vanes are positioned entirely upstream of the fan band.
Claim 34
Dependent Claim
19 words
The fan and housing combination of claim 1 or claim 26 wherein said vanes have a beveled end face.
Claim 35
Dependent Claim
21 words
The fan and housing combination of claim 32 wherein the end faces of said vanes are beveled by at least 20°.
Claim 36
Dependent Claim
25 words
The fan and housing combination of claim 26 wherein said vanes are arranged in an array whose inward tips are connected by an inner ring.
Claim 37
Dependent Claim
29 words
The fan and housing combination of claim 32 in which the high pressure side of the vanes has a concave portion adjacent to the end face of the vanes.
Claim 38
Dependent Claim
31 words
The fan and housing combination of claim 35 in which the radius of said concave portion is between 0.1 S and 1.0 S, where S is the spacing between adjacent vanes.
Claim 39
Dependent Claim
27 words
The fan and housing combination of claim 35 in which the high pressure side of said vanes is curved in a plane normal to the fan axis.
Claim 40
Dependent Claim
45 words
The fan and housing combination of claim 37 in which the high pressure side of said vanes is substantially cylindrical in a plane normal to the fan axis, having a radius of curvature between 0.15 D and 0.3 D, where D is the fan diameter.
Claim 41
Dependent Claim
103 words
The fan and housing combination of claim 34 in which: a) the end faces of said vanes are beveled by at least 20°; b) the high pressure side of the vanes has a concave portion adjacent to the end face of the vanes, having a radius of curvature of between 0.1 S and 1.0 S, where S is the spacing between adjacent vanes; and c) the high pressure side of the vanes is substantially cylindrical in section in a plane normal to the fan axis, having a radius of curvature of between 0.15 D and 0.3 D, where D is the fan diameter.
Claim 42
Dependent Claim
26 words
The fan and housing combination of claim 18 in which elongated motor supports extend radially inwardly from said shroud portion to a centrally positioned motor mount.
Claim 43
Dependent Claim
19 words
The fan and housing combination of claim 9 in which the radially innermost face of the vanes is beveled.
Claim 44
Dependent Claim
110 words
A combination axial flow automotive fan and housing, said fan having a hub that rotates on an axis and blades extending outwardly from the hub to a circular band that connects the blade tips, the combination also comprising a housing surrounding the fan to control airflow, the combination being characterized in that: a) a portion of the housing is positioned outward of the fan band and there are running clearances between the band and the housing such that recirculating airflow moves in a pathway between the fan and the housing; and b) stationary flow control vanes are connected to the housing in a position to encounter and redirect recirculating airflow.
Claim 45
Dependent Claim
110 words
A combination axial flow automotive fan and housing, said fan having a hub that rotates on an axis and blades extending outwardly from the hub to a circular band that connects the blade tips, the combination also comprising a housing surrounding the fan to control airflow, the combination being characterized in that: a) a portion of the housing is positioned outward of the fan band and there are running clearances between the band and the housing such that recirculating airflow moves in a pathway between the fan and the housing; and b) stationary flow control vanes are connected to the housing in a position to encounter and redirect recirculating airflow.
References Cited (Backward Citations)
US2981461A
Cited
US3189260A
Cited
US3307776A
Cited
US3285501A
Cited
US3447741A
Cited
DE1905269A1
Cited
US3620640A
Cited
US3677660A
Cited
US3627440A
Cited
US3842902A
Cited
DE2462465A1
Cited
US4370094A
Cited
US3972646A
Cited
US4357914A
Cited
USRE32462E
Cited
US4432694A
Cited
SU918559A1
Cited
US4358245A
Cited
US4685513A
Cited
US4448573A
Cited
US4871294A
Cited
GB2124303A
Cited
EP0118769A2
Cited
EP0122892A1
Cited
US4630993A
Cited
US4548548A
Cited
EP0168594A1
Cited
WO1986001263A1
Cited
US4569631A
Cited
US4673331A
Cited
US4791520A
Cited
JPS62282198A
Cited
US4871298A
Cited
US4900229A
Cited
US4981461A
Cited
US5000660A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-02-05 | 1999-08-07 | 2000-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-02-05 | 2003-08-07 | 2004-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-02-05 | 2007-08-07 | 2008-02-06 | $7700.00 | Window Closed / Lapsed |