US4761115A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Axial-flow fan
Assignee: Alcatel Lucent Deutschland AG
•
Filing: 1986-12-17
•
Granted: 1988-08-02
•
Expires: 2006-12-17
Abstract
Abstract A frame-supported fan in which the mounting portions between the motor and the frame are formed in the shape of an arrowhead and/or are provided with sculptured edges extending to the frame or are provided with interfering bodies mounted to the outer ends of the edges of the frame, so as to reduce unwanted noise by producing non-uniform flow separation in the air stream through the fan.
Inventors
- 👤 Reinhold Hopfensperger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:13
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/66; F04D29/661; F04D29/663; F04D25/00; F04D25/02; F04D25/06; F04D25/0606; F04D25/0613; F04D29/40; F04D29/52; F04D29/54; F04D29/541; F04D29/542; F04D29/544; Y; Y10; Y10S; Y10S415/00; Y10S415/914
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
149 words
An axial flow fan comprising: a frame having a central opening therein; fan blades rotatably mounted for rotation in a plane within said frame central opening to produce an airstream through said fan; an electric motor coupled to said blades to rotate said blades and positioned inside said central opening; and arrowhead-shaped mounting portions connecting said frame and said electric motor to attach said motor to said frame, each of said mounting portions being V-shaped in a plane parallel to the plane of rotation of said blades and having a tip between said frame and said motor, said mounting portions being oriented so that the tips point point in a circumferential direction relative to the center of rotation of said blades; whereby said mounting portions guide the airstream through the fan and produce an air flow separation so that the generation of siren-like noise by the fan is suppressed.
Claim 2
Dependent Claim
149 words
An axial flow fan comprising: a frame having a central opening therein; fan blades rotatably mounted for rotation in a plane within said frame central opening to produce an airstream through said fan; an electric motor coupled to said blades to rotate said blades and positioned inside said central opening; and arrowhead-shaped mounting portions connecting said frame and said electric motor to attach said motor to said frame, each of said mounting portions being V-shaped in a plane parallel to the plane of rotation of said blades and having a tip between said frame and said motor, said mounting portions being oriented so that the tips point point in a circumferential direction relative to the center of rotation of said blades; whereby said mounting portions guide the airstream through the fan and produce an air flow separation so that the generation of siren-like noise by the fan is suppressed.
Claim 3
Dependent Claim
48 words
The axial flow fan of claim 1 wherein said mounting portions have edges, said edges have outer ends extending to said frame, and wherein said edges are sculptured in areas near said outer ends to reduce the generation of noise by producing non-uniform flow separation in the airstream.
Claim 4
Dependent Claim
15 words
The axial flow fan of claim 2 wherein the sculptured edges have a sawtooth-shaped texture.
Claim 5
Dependent Claim
16 words
The axial flow fan of claim 2 wherein the sculptured edges have a stepped surface structure.
Claim 6
Dependent Claim
46 words
The axial flow fan of claim 1, further comprising an interfering body, said mounting portions have outer ends extending to said frame, said interfering body being mounted to the outer end of one of said mounting portions to limit the noise level produced by the fan.
Claim 7
Dependent Claim
22 words
The axial flow fan of claim 5 wherein said interfering body has the shape of a step extending in the circumferential direction.
Claim 8
Dependent Claim
115 words
An axial flow fan, comprising: a frame having a central opening therein: fan blades rotatably mounted within said frames central opening to produce an airstream through said fan; an electric motor coupled to said blades to rotate said blades in a rotational direction and positioned inside said central opening; and mounting portions connecting said frame and said electric motor to attach said motor to said frame, said mounting portions having edges, said edges having outer ends extending to said frame, said edges facing in a circumferential direction opposite to said rotational direction and being sculptured in areas near said outer ends to reduce the generation of noise by producing non-uniform flow separation in the airstream.
Claim 9
Dependent Claim
115 words
An axial flow fan, comprising: a frame having a central opening therein: fan blades rotatably mounted within said frames central opening to produce an airstream through said fan; an electric motor coupled to said blades to rotate said blades in a rotational direction and positioned inside said central opening; and mounting portions connecting said frame and said electric motor to attach said motor to said frame, said mounting portions having edges, said edges having outer ends extending to said frame, said edges facing in a circumferential direction opposite to said rotational direction and being sculptured in areas near said outer ends to reduce the generation of noise by producing non-uniform flow separation in the airstream.
Claim 10
Dependent Claim
16 words
An axial flow fan as in claim 7, wherein the sculptured edges have a sawtooth-shaped texture.
Claim 11
Dependent Claim
17 words
An axial flow fan as in claim 7, wherein the sculptured edges have a stepped surface structure.
Claim 12
Dependent Claim
134 words
An axial flow fan, comprising: a frame having a central opening therein: fan blades rotatably mounted within said frame central opening to produce an airstream through said fan; an electric motor coupled to said blades to rotate said blades in a rotational direction and positioned inside said central opening; mounting portions connecting said frame and said electric motor to attach said motor to said frame, said mounting portions having outer ends extending to said frame, said outer ends having front edges, said front edges facing in a circumferential direction opposite to said rotational direction; and interfering bodies mounted to said outer ends at said front edges so as to effectively widen said outer ends in said circumferential direction thereby to produce a non-uniform flow separation in the airstream which reduces the generation of noise.
Claim 13
Dependent Claim
134 words
An axial flow fan, comprising: a frame having a central opening therein: fan blades rotatably mounted within said frame central opening to produce an airstream through said fan; an electric motor coupled to said blades to rotate said blades in a rotational direction and positioned inside said central opening; mounting portions connecting said frame and said electric motor to attach said motor to said frame, said mounting portions having outer ends extending to said frame, said outer ends having front edges, said front edges facing in a circumferential direction opposite to said rotational direction; and interfering bodies mounted to said outer ends at said front edges so as to effectively widen said outer ends in said circumferential direction thereby to produce a non-uniform flow separation in the airstream which reduces the generation of noise.
Claim 14
Dependent Claim
23 words
An axial flow fan as in claim 10, wherein said interfering body has the shape of a step extending in said circumferential direction.
References Cited (Backward Citations)
GB441269A
Cited
US2142307A
Cited
GB983469A
Cited
US3362627A
Cited
US3362627B1
Cited
DE2414695A1
Cited
DE2529541A1
Cited
US4089618A
Cited
DE2618894A1
Cited
JPS55112899A
Cited
US4482302A
Cited
DE3234011A1
Cited
EP0111443A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-08-02 | 1992-02-01 | 1992-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-02 | 1996-02-01 | 1996-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-02 | 2000-02-01 | 2000-08-02 | $7700.00 | Window Closed / Lapsed |