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US4756728A
Expired / Lapsed
US
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Air filtering device
Assignee: ECKSTROM WILLIAM R
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Filing: 1987-08-19
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Granted: 1988-07-12
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Expires: 2007-08-19
Abstract
Abstract A satellite pre-filter cabinet positions replaceable air filters in an area in which air polluting harmful industrial dusts, including friable asbestos and/or fumes and gases are present and must be removed. The satellite air filter cabinet is connected to negative air pressure devices and filters remotely situated as for example outside of the polluted area.
Inventors
- 👤 John R. Conrad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:23
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/10; F; F24; F24F; F24F13/00; F24F13/28; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02A50/2351
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
175 words
A portable satellite air filtering device for use with a negative air pressure machine having a primary air filter therein comprises a horizontally disposed base frame having front, back and side frame members, an upstanding fixed frame on said front frame member, said fixed frame having upper, lower and side frame members defining an area on one side thereof in which a replaceable air filter element is removably positioned, a secondary upstanding frame movably attached to said front frame member in spaced relation to said fixed frame for movement toward and away from said fixed frame and said replaceable air filter element, funnel means on the other side of said fixed frame and above said base frame in communication with said fixed frame and a flexible air conducting hose detachably connected to said funnel means and to and in communication with said negative air pressure machine and said primary air filter wherey said replaceable air filter element in said satellite air filtering device prefilters air flowing to said primary filter and negative air pressure machine.
Claim 2
Dependent Claim
175 words
A portable satellite air filtering device for use with a negative air pressure machine having a primary air filter therein comprises a horizontally disposed base frame having front, back and side frame members, an upstanding fixed frame on said front frame member, said fixed frame having upper, lower and side frame members defining an area on one side thereof in which a replaceable air filter element is removably positioned, a secondary upstanding frame movably attached to said front frame member in spaced relation to said fixed frame for movement toward and away from said fixed frame and said replaceable air filter element, funnel means on the other side of said fixed frame and above said base frame in communication with said fixed frame and a flexible air conducting hose detachably connected to said funnel means and to and in communication with said negative air pressure machine and said primary air filter wherey said replaceable air filter element in said satellite air filtering device prefilters air flowing to said primary filter and negative air pressure machine.
Claim 3
Dependent Claim
44 words
The portable satellite air filtering device set forth in claim 1 and wherein said upstanding fixed frame comprises upper, lower and side frame members of cross sectionally L-shape positioned so as to be able to receive and hold said replaceable air filter element therein.
Claim 4
Dependent Claim
64 words
The portable satellite air filtering device set forth in claim 1 and wherein said upstanding fixed frame and said secondary upstanding frame each comprise upper, lower and side frame members of cross sectionally L-shape positioned in oppositely disposed relation to one another defining said area on said one side of said upstanding fixed frame in which said replaceable air filter element is removably positioned.
Claim 5
Dependent Claim
50 words
The portable satellite air filtering device set forth in claim 1 and wherein said upstanding fixed frame is vertically positioned on said base frame above said front frame member thereof and said funnel means in communication with said upstanding fixed frame is positioned rearwardly thereof substantially above said base frame.
Claim 6
Dependent Claim
80 words
The portable satellite air filtering device set forth in claim 1 and wherein said upstanding fixed frame is positioned on said base frame adjacent said front frame member thereof and said funnel means in communication with said upstanding fixed frame is positioned rearwardly thereof substantially above said base frame, and wherein said secondary upstanding frame is movable from a first position adjacent said upstanding fixed frame to a second position outwardly thereof in a direction opposite to said funnel means.
Claim 7
Dependent Claim
29 words
The portable satellite air filtering device set forth in claim 4 and wherein braces are positioned between said base frame and said upstanding fixed frame on angles relative thereto.
Claim 8
Dependent Claim
91 words
The portable satellite air filtering device set forth in claim 1 and wherein said secondary upstanding frame comprises upper, lower and side frame members defining an area on one side thereof in which said replaceable air filter element is removably positioned and wherein spring hinges connect and position said lower frame members of the upstanding fixed frame and the lower frame members of said secondary upstanding frame so that said secondary upstanding frame is movable toward and away from said upstanding fixed frame on an arc based on said spring hinges.
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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) | 1991-07-12 | 1992-01-11 | 1992-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-12 | 1996-01-11 | 1996-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-12 | 2000-01-11 | 2000-07-12 | $7700.00 | Window Closed / Lapsed |