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US4749390A Expired / Lapsed US ⏱️ 0.0 years remaining

Four-sided air filter

Assignee: AIR PURIFICATION PRODUCTS INTERNATIONAL PO BOX 454 ROYSE CITY TEXAS 75089 A TEXAS CORP
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Filing: 1987-02-26
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Granted: 1988-06-07
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Expires: 2007-02-26
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Abstract

Abstract A filtering unit (10) has four filter holders (20) arranged in a rectangle around a blower (36). Each filter holder holds up to two filter elements (11). The blower draws air through the filter elements (11) and outputs filtered air through a vent (40). Refillable filter frames (16) are provided to allow the user to change the filter material (18). In one embodiment, glass chips are used as the filter material (18).

Inventors

  • 👤 Gilbert W. Burnett
  • 👤 Paul D. Jackson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 19:15
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/10; B01D46/12; B01D46/30; Y; Y10; Y10S; Y10S55/00; Y10S55/31

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 119 words
Apparatus for filtering air comprising: a blower having an intake for drawing air and an exhaust for outputting air; a rectangular housing for enclosing said blower; four apertures formed in the sides of said housing; respective filter holders adjacent said apertures extending across said apertures; filter elements slideably engaged in said filter holders; said filter elements comprising a filter material for filtering unwanted particles from the air and a filter frame for replaceably holding said filter material; and said intake operable to draw air successively through said filter elements such that air filtered by filter elements is output from said exhaust such that unfiltered air may be drawn through said filtered elements slowly in relation to the exhaust speed.
Claim 2
Dependent Claim 119 words
Apparatus for filtering air comprising: a blower having an intake for drawing air and an exhaust for outputting air; a rectangular housing for enclosing said blower; four apertures formed in the sides of said housing; respective filter holders adjacent said apertures extending across said apertures; filter elements slideably engaged in said filter holders; said filter elements comprising a filter material for filtering unwanted particles from the air and a filter frame for replaceably holding said filter material; and said intake operable to draw air successively through said filter elements such that air filtered by filter elements is output from said exhaust such that unfiltered air may be drawn through said filtered elements slowly in relation to the exhaust speed.
Claim 3
Dependent Claim 33 words
The apparatus of claim 1 wherein a first filter element is operable to filter particulates from the air and a second filter element is operable to filter odors and chemicals from the air.
Claim 4
Dependent Claim 13 words
The apparatus of claim 1 wherein said blower is a wheel type blower.
Claim 5
Dependent Claim 16 words
The apparatus of claim 1 wherein said blower is adjustable over a plurality of speed settings.
Claim 6
Dependent Claim 20 words
The apparatus of claim 1 and further comprising means for directing the output air flow in a plurality of directions.
Claim 7
Dependent Claim 15 words
The apparatus of claim 1 wherein said blower operates on either AC or DC voltage.
Claim 8
Dependent Claim 41 words
The apparatus of claim 1 wherein ones of said filter holders hold a first filter element and other ones of said filter holders hold a second filter element, said second filter element having different filtering properties than said first filter element.
Claim 9
Dependent Claim 20 words
The apparatus of claim 7 wherein said first filter element contains charcoal and said second filter element contains potassium permanganate.
Claim 10
Dependent Claim 157 words
Apparatus for filtering air comprising: a blower having an intake for drawing air and an exhaust for outputting air, said blower operating at a plurality of speeds; a housing for enclosing said blower, said housing having four apertures formed therein, said apertures configured in a rectangle enclosing said blower; four filter holders through which air is drawn by said blower, each of said filter holder operable to hold filter elements across said apertures; said filter elements comprising a filter material for filtering unwanted particles from the air and a filter frame for enclosing said filter material, said filter frame allowing easy replacement of the filter material enclosed therein; said filter elements interchangeably disposed within said filter holding means, such that filter elements can be easily replaced within the filter holding means; and a hinge top portion having means for directing the airflow out of said exhaust and allowing access to said filter elements within said filter holders.
Claim 11
Dependent Claim 157 words
Apparatus for filtering air comprising: a blower having an intake for drawing air and an exhaust for outputting air, said blower operating at a plurality of speeds; a housing for enclosing said blower, said housing having four apertures formed therein, said apertures configured in a rectangle enclosing said blower; four filter holders through which air is drawn by said blower, each of said filter holder operable to hold filter elements across said apertures; said filter elements comprising a filter material for filtering unwanted particles from the air and a filter frame for enclosing said filter material, said filter frame allowing easy replacement of the filter material enclosed therein; said filter elements interchangeably disposed within said filter holding means, such that filter elements can be easily replaced within the filter holding means; and a hinge top portion having means for directing the airflow out of said exhaust and allowing access to said filter elements within said filter holders.
Claim 12
Dependent Claim 123 words
Filter apparatus for holding a granulated filtering material comprising: two perforated panels having opposite edge portions formed normal to the face of said panels; side members each having an integral screw boss disposed along the length of said side members forming channels for engaging said edge portions of said perforated panels, said side members holding said perforated panels a predetermined distance apart; and a top member removably engaged to said side members by screws extending into the bosses to allow a user to fill the cavity formed by the perforated panels with granulated filter material, said granulated material having particle sizes greater than the perforations in said panels, such that a filter element is formed to filter air passing through said perforated panels.
Claim 13
Dependent Claim 123 words
Filter apparatus for holding a granulated filtering material comprising: two perforated panels having opposite edge portions formed normal to the face of said panels; side members each having an integral screw boss disposed along the length of said side members forming channels for engaging said edge portions of said perforated panels, said side members holding said perforated panels a predetermined distance apart; and a top member removably engaged to said side members by screws extending into the bosses to allow a user to fill the cavity formed by the perforated panels with granulated filter material, said granulated material having particle sizes greater than the perforations in said panels, such that a filter element is formed to filter air passing through said perforated panels.
Claim 14
Dependent Claim 29 words
The apparatus of claim 10 and further comprising a divider disposed between said perforated panels to assist said side members in spacing said perforated panels by said predetermined distance.
Claim 15
Dependent Claim 17 words
The apparatus of claim 10 wherein said perforated panels have holes measuring approximately 70/1000 inches in diameter.
Claim 16
Dependent Claim 90 words
A washable filter comprising: two washable electrostatic polyprophylene filter panels; a first frame holding one of said washable filter panels, said first frame having a leaf spring a second frame holding the other of said washable filter panels, said second frame having side members containing a charcoal filter material and a rim disposed about said side members; and said first frame operable to enclose said filter material within said second frame, such that said first frame fits within said rim only when said leaf spring is in a compressed position.
Claim 17
Dependent Claim 90 words
A washable filter comprising: two washable electrostatic polyprophylene filter panels; a first frame holding one of said washable filter panels, said first frame having a leaf spring a second frame holding the other of said washable filter panels, said second frame having side members containing a charcoal filter material and a rim disposed about said side members; and said first frame operable to enclose said filter material within said second frame, such that said first frame fits within said rim only when said leaf spring is in a compressed position.

References Cited (Backward Citations)

US4115082A Cited
US4252547A Cited
US4504290A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-06-07 1991-12-07 1992-06-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-06-07 1995-12-07 1996-06-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-06-07 1999-12-07 2000-06-07 $7700.00 Window Closed / Lapsed

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