US4750860A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fan
Assignee: Tandem Computers Inc
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Filing: 1987-01-20
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Granted: 1988-06-14
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Expires: 2007-01-20
Abstract
Abstract An improved fan, for mounting adjacent an opening in a mounting plate, includes blades rotatable about an axis and within a cylindrical housing. The fan blades move air through the opening in the mounting plate. A cylindrical, open-cell foam collar encircles the fan housing. The collar is sized so that the collar extends a substantial distance upstream past the edge of the collar. The foam collar reduces the acoustic noise from the fan by damping the housing vibration and also by acting as a barrier to muffle sound waves in the air. In addition, the foam collar straightens out the air flow prior to entering the fan blades making it more laminar and less turbulent to increase the efficiency of the fan.
Inventors
- 👤 Francis E. Kelley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:58
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/66; F04D29/661; F04D29/663; F04D29/664; F04D29/40; F04D29/52; F04D29/54; F04D29/541; F04D29/545
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
160 words
An improved fan assembly comprising: a fan including blades rotatable about an axis, the fan operable to move air in a downstream direction along the axis; a cylindrical fan housing mounted about the fan blades coaxially with the axis so to surround the fan blades, the fan housing being a chosen axial length with a downstream edge and an upstream edge; and a tubular foam collar sized to fit over the fan housing, the collar having a first portion, extending over the housing a first length in the downstream direction from the upstream edge, and a second portion, extending a second length from the upstream edge in an upstream direction opposite the downstream direction, the second length being at least a substantial portion of the first length; whereby the foam collar reduces the noise from the fan assembly, by damping vibration of the fan housing and by muffling sound waves, and increases the air flow rate through the fan assembly.
Claim 2
Dependent Claim
160 words
An improved fan assembly comprising: a fan including blades rotatable about an axis, the fan operable to move air in a downstream direction along the axis; a cylindrical fan housing mounted about the fan blades coaxially with the axis so to surround the fan blades, the fan housing being a chosen axial length with a downstream edge and an upstream edge; and a tubular foam collar sized to fit over the fan housing, the collar having a first portion, extending over the housing a first length in the downstream direction from the upstream edge, and a second portion, extending a second length from the upstream edge in an upstream direction opposite the downstream direction, the second length being at least a substantial portion of the first length; whereby the foam collar reduces the noise from the fan assembly, by damping vibration of the fan housing and by muffling sound waves, and increases the air flow rate through the fan assembly.
Claim 3
Dependent Claim
73 words
The fan assembly of claim 1 further comprising a mounting plate having first and second sides and an air flow opening formed therein, the fan being mounted to the first side of the mounting plate at the air flow opening so that air flows from the first mounting plate side, through the opening and to the first mounting plate side, and wherein the downstream edge of the housing is adjacent the mounting plate.
Claim 4
Dependent Claim
17 words
The fan assembly of claim 2 wherein the fan housing is mounted directly to the mounting plate.
Claim 5
Dependent Claim
12 words
The fan assembly of claim 1 wherein the foam collar is cylindrical.
Claim 6
Dependent Claim
19 words
The fan assembly of claim 1 wherein the foam collar has a radial thickness of at least 1/2 inch.
Claim 7
Dependent Claim
15 words
The fan assembly of claim 1 wherein the foam collar is an open-cell foam collar.
Claim 8
Dependent Claim
16 words
The fan assembly of claim 6 wherein the foam collar has about 60-90 pores per inch.
Claim 9
Dependent Claim
26 words
The fan assembly of claim 1 wherein the first length of the foam collar is substantially equal to the chosen axial length of the fan housing.
Claim 10
Dependent Claim
52 words
The fan assembly of claim 1 wherein the fan has a diameter of about 6 inches, the fan housing has a chosen axial length of about 11/2 inches, the first and second lengths of the collar are each about 11/2 inches and the collar has a radial dimension of about 3/4 inch.
Claim 11
Dependent Claim
204 words
An improved fan assembly comprising: a mounting plate having first and second sides and an air flow opening formed therein; a fan, including blades rotatable about an axis, mounted to the first side of the mounting plate at the air flow opening, the fan operable to blow air in a forward direction along the axis from the first side, through the opening and to the second side; a cylindrical fan housing mounted about the fan blades coaxially with the axis so as to surround the fan blades and on the first side of the mounting plate, the fan housing being a chosen axial length with a downstream edge adjacent the mounting plate and an upstream edge spaced apart from the mounting plate; and a cylindrical, open-cell foam collar sized to fit over the fan housing, the collar having a first portion, housing a first length, covering the housing and a second portion extending in an upstream direction opposite the downstream direction, the second length being generally equal to the first length; whereby the foam collar reduces the noise from the fan assembly, by damping vibration of the fan housing and by muffling sound waves, and increases the air flow rate through the fan assembly.
Claim 12
Dependent Claim
204 words
An improved fan assembly comprising: a mounting plate having first and second sides and an air flow opening formed therein; a fan, including blades rotatable about an axis, mounted to the first side of the mounting plate at the air flow opening, the fan operable to blow air in a forward direction along the axis from the first side, through the opening and to the second side; a cylindrical fan housing mounted about the fan blades coaxially with the axis so as to surround the fan blades and on the first side of the mounting plate, the fan housing being a chosen axial length with a downstream edge adjacent the mounting plate and an upstream edge spaced apart from the mounting plate; and a cylindrical, open-cell foam collar sized to fit over the fan housing, the collar having a first portion, housing a first length, covering the housing and a second portion extending in an upstream direction opposite the downstream direction, the second length being generally equal to the first length; whereby the foam collar reduces the noise from the fan assembly, by damping vibration of the fan housing and by muffling sound waves, and increases the air flow rate through the fan assembly.
Claim 13
Independent Claim
109 words
A method for improving the performance of a fan of the type mounted to a mounting structure adjacent an opening in the mounting structure so to blow air through the opening, the fan having blades surrounded by a cylindrical fan housing having upstream and downstream edges, the method comprising: selecting a foam collar having an inside dimension sized for snug placement over the fan housing and having a chosen axial length; and mounting the foam collar over the fan housing with a substantial portion of the foam collar extending on either side of the upstream edge so the foam collar both reduces noise and aids flow through the fan.
Claim 14
Independent Claim
109 words
A method for improving the performance of a fan of the type mounted to a mounting structure adjacent an opening in the mounting structure so to blow air through the opening, the fan having blades surrounded by a cylindrical fan housing having upstream and downstream edges, the method comprising: selecting a foam collar having an inside dimension sized for snug placement over the fan housing and having a chosen axial length; and mounting the foam collar over the fan housing with a substantial portion of the foam collar extending on either side of the upstream edge so the foam collar both reduces noise and aids flow through the fan.
Claim 15
Dependent Claim
33 words
The method of claim 11 wherein the selecting step includes the step of selecting a foam collar with a chosen axial length being substantially greater than the axial length of the fan housing.
Claim 16
Dependent Claim
20 words
The method of claim 12 wherein the chosen axial length is about twice the axial length of the fan housing.
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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) | 1991-06-14 | 1991-12-14 | 1992-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-14 | 1995-12-14 | 1996-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-14 | 1999-12-14 | 2000-06-14 | $7700.00 | Window Closed / Lapsed |