US4946348A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Centrifugal fan with airfoil vanes in annular volute envelope
Assignee: Bosch Automotive Motor Systems Corp
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Filing: 1989-11-17
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Granted: 1990-08-07
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Expires: 2009-11-17
Abstract
Abstract A rearwardly curved centrifugal blower having an annular envelope around the impeller, so that the rotating impeller draws air in through a central inlet and forces it radially outward into the envelope and out of an annular discharge. Multiple airfoil vanes are positioned in the annular envelope, in two axially displaced stages. The vanes are angled to turn and diffuse airflow entering the envelope.
Inventors
- 👤 Martin G. Yapp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:34
CPC Classifications
F; F04; F04D; F04D17/00; F04D17/08; F04D17/16; F04D29/00; F04D29/26; F04D29/28; F04D29/281; F04D29/30; F04D29/40; F04D29/42; F04D29/44; F04D29/441; F04D29/444; F04D29/58; F04D29/582; F04D29/5826; F05; F05D; F05D2250/00; F05D2250/50; F05D2250/52
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
115 words
A centrifugal blower comprising (a) an impeller mounted to rotate on an axis, said impeller comprising a plurality of rearwardly curved blades which draw air in through a central inlet and force air radially outward, into an annular envelope around said impeller, and out of an annular discharge from said envelope, and (b) a plurality of airfoil vanes positioned in said annular envelope; said airfoil vanes being positioned to form at least two stages axially displaced with respect to each other; said vanes being angled with respect to airflow entering said envelope to turn and diffuse airflow in said envelope, converting swirl energy into pressure, said blower having a blade chord Reynolds number of 40,000-200,000.
Claim 2
Dependent Claim
115 words
A centrifugal blower comprising (a) an impeller mounted to rotate on an axis, said impeller comprising a plurality of rearwardly curved blades which draw air in through a central inlet and force air radially outward, into an annular envelope around said impeller, and out of an annular discharge from said envelope, and (b) a plurality of airfoil vanes positioned in said annular envelope; said airfoil vanes being positioned to form at least two stages axially displaced with respect to each other; said vanes being angled with respect to airflow entering said envelope to turn and diffuse airflow in said envelope, converting swirl energy into pressure, said blower having a blade chord Reynolds number of 40,000-200,000.
Claim 3
Dependent Claim
17 words
The blower of claim 1 comprising means to attach a flow resistance element to said annular discharge.
Claim 4
Dependent Claim
24 words
The blower of claim 1 in which the inner diameter of said annulus is at least 80% of the outer diameter of said annulus.
Claim 5
Dependent Claim
57 words
The blower of claim 1, said blower blades being angled to generate flow entering said annular envelope at an angle between 60° and 70° with respect to the blower axis, said vanes turning the flow in the envelope to produce a flow at said annular discharge of between 0° and 10° with respect to the blower axis.
Claim 6
Dependent Claim
46 words
The blower of claim 1, said blower blades generating flow entering said annular envelope with a velocity of between 50 and 100 feet/sec., said vanes being sized and position to diffuse flow in said annular envelope to between 15 and 40 feet/sec. at said annular discharge.
Claim 7
Dependent Claim
17 words
The blower of claim 1 further comprising means to attach a heat exchanger to said annular discharge.
Claim 8
Dependent Claim
15 words
The blower of claim 1 in which said blower diameter is less than 2 feet.
Claim 9
Dependent Claim
15 words
The blower of claim 1 in which said blower diameter is less than 1 foot.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-06 | 1994-02-05 | 1994-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-06 | 1998-02-05 | 1998-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-06 | 2002-02-05 | 2002-08-07 | $7700.00 | Window Closed / Lapsed |