US4569631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High strength fan
Assignee: Bosch Automotive Motor Systems Corp
•
Filing: 1984-08-06
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Granted: 1986-02-11
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Expires: 2004-08-06
Abstract
Abstract A fan in which the root-to-tip net blade skew angle (Ab) (either forward or rearward) is less than 1/2 of the blade spacing; in a first radially inward region of the blade, the blade is rearwardly skewed as indicated by the leading edge skew angle (Ae); in a second region radially outward of the first region, the leading edge skew angle indicates a forward skew.
Inventors
- 👤 Leslie M. Gray, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:43
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/26; F04D29/32; F04D29/38; F04D29/384; F04D29/386; F04D29/325; F04D29/326; Y; Y10; Y10S; Y10S416/00; Y10S416/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
185 words
A cooling fan, and means for maintaining said fan in association with a heat exchanger in position to move air through the heat exchanger, said fan comprising a hub rotatable on an axis, a plurality of plastic blades, each of which extends radially outward from a root region attached to said hub to a tip region, and a cylindrical band extending concentrically around said fan axis, said band connecting said blade tip regions, said blades being characterized in that: (a) the leading edge of each said blade is rearwardly angled in said root region and forwardly angled in said tip region, said blades having a leading edge skew angle of at least 30° rearwardly in at least one portion of said root region and a leading edge skew angle of at least 30° forwardly in at least one portion of said tip region; (b) said blades having a net mid-chord line blade skew less than 1/2 of the blade spacing angle; and (c) said blades have a blade angle which is approximately constant for the position of the blade where r/R is greater than 0.7.
Claim 2
Dependent Claim
185 words
A cooling fan, and means for maintaining said fan in association with a heat exchanger in position to move air through the heat exchanger, said fan comprising a hub rotatable on an axis, a plurality of plastic blades, each of which extends radially outward from a root region attached to said hub to a tip region, and a cylindrical band extending concentrically around said fan axis, said band connecting said blade tip regions, said blades being characterized in that: (a) the leading edge of each said blade is rearwardly angled in said root region and forwardly angled in said tip region, said blades having a leading edge skew angle of at least 30° rearwardly in at least one portion of said root region and a leading edge skew angle of at least 30° forwardly in at least one portion of said tip region; (b) said blades having a net mid-chord line blade skew less than 1/2 of the blade spacing angle; and (c) said blades have a blade angle which is approximately constant for the position of the blade where r/R is greater than 0.7.
Claim 3
Dependent Claim
21 words
The fan of claim 1 wherein said net mid-chord blade skew angle is less than 1/3 of the blade spacing angle.
Claim 4
Dependent Claim
22 words
The fan of claim 1 wherein said root region extends radially outward to a value of r/R of at least 0.6. PG,11
Claim 5
Dependent Claim
16 words
The fan of claim 1 wherein said net mid-chord blade skew angle is less than 30°.
Claim 6
Dependent Claim
18 words
The fan of claim 1 wherein said blades are raked to be out of the plane of rotation.
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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) | 1989-02-10 | 1989-08-12 | 1990-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-10 | 1993-08-12 | 1994-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-10 | 1997-08-12 | 1998-02-11 | $7700.00 | Window Closed / Lapsed |