US5925320A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air purification system
Assignee: INDOOR AIR TECHNOLOGY Ltd
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Filing: 1997-06-04
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Granted: 1999-07-20
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Expires: 2017-06-04
Abstract
Abstract An air purification system comprises a housing, a generally S-shaped duct mounted within the housing, at least one blower mounted within the housing for circulating air through the system, and purification structure for removing contaminants from the air. The system preferably comprises two blowers, a master control switch for activating one of the blowers to circulate air through the filter, and a secondary control switch for activating the other blower and the UVC source to initiate a UVC purification process to further purify the filtered air.
Inventors
- 👤 John P. Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:41
CPC Classifications
A; A61; A61L; A61L2/00; A61L2/02; A61L2/08; A61L2/10
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
221 words
An air purification system comprising: a housing having an intake opening for permitting air to enter the housing and an outlet opening for permitting air to exit the housing; a curved hollow duct positioned at least partially inside the housing and having a passage extending between an inlet end in communication with the intake opening of the housing and an outlet end in communication with the outlet opening of the housing, the passage having a gradually decreasing cross sectional area between the inlet end and a narrow-most section positioned along the passage and a gradually increasing cross sectional area between the narrow section and the outlet end, the narrow-most section having opposite first and second sides, the passage curving at the narrow-most section so that said first side of the narrow-most section is concave; a blower in communication with the passage for drawing air through the housing intake opening and blowing air through the passage from the inlet end to the outlet end; and an ultraviolet energy source mounted in the narrow-most section parallel to said first side of the narrow-most section of the passage adjacent said second side so that substantially all of the air blown through the passage passes between the energy source and said first side of the narrow-most section in an arcuate path around said energy source.
Claim 2
Dependent Claim
221 words
An air purification system comprising: a housing having an intake opening for permitting air to enter the housing and an outlet opening for permitting air to exit the housing; a curved hollow duct positioned at least partially inside the housing and having a passage extending between an inlet end in communication with the intake opening of the housing and an outlet end in communication with the outlet opening of the housing, the passage having a gradually decreasing cross sectional area between the inlet end and a narrow-most section positioned along the passage and a gradually increasing cross sectional area between the narrow section and the outlet end, the narrow-most section having opposite first and second sides, the passage curving at the narrow-most section so that said first side of the narrow-most section is concave; a blower in communication with the passage for drawing air through the housing intake opening and blowing air through the passage from the inlet end to the outlet end; and an ultraviolet energy source mounted in the narrow-most section parallel to said first side of the narrow-most section of the passage adjacent said second side so that substantially all of the air blown through the passage passes between the energy source and said first side of the narrow-most section in an arcuate path around said energy source.
Claim 3
Dependent Claim
23 words
An air purification system as set forth in claim 1 wherein said first side of the narrow-most section has an inner reflective surface.
Claim 4
Dependent Claim
35 words
An air purification system as set forth in claim 1 wherein the energy source and said first side of the narrow-most section are spaced by a distance of between about 1.5 and about 2.0 inches.
Claim 5
Dependent Claim
31 words
An air purification system as set forth in claim 1 wherein the energy source and said second side of the narrow-most section are spaced by a distance of about 0.125 inches.
Claim 6
Dependent Claim
18 words
An air purification system as set forth in claim 1 wherein the ultraviolet source is a UVC source.
Claim 7
Dependent Claim
29 words
An air purification system as set forth in claim 1 further comprising a filter mounted in the housing so that air blown through the passage passes through the filter.
Claim 8
Dependent Claim
24 words
An air purification system as set forth in claim 6 wherein the filter is mounted in the housing upstream from the ultraviolet energy source.
Claim 9
Dependent Claim
22 words
An air purification system as set forth in claim 7 wherein the filter is mounted at the intake opening of the housing.
Claim 10
Dependent Claim
39 words
An air purification system as set forth in claim 1 wherein the passage has a gradually increasing cross sectional area over more than half of a distance extending from the narrow-most section to the outlet end of the passage.
Claim 11
Dependent Claim
25 words
An air purification system as set forth in claim 1 wherein the curved narrow-most section turns the air through an arc of approximately 180 degrees.
Claim 12
Dependent Claim
25 words
An air purification system as set forth in claim 1 wherein the passage is curved between the narrow-most section and the outlet of the passage.
Claim 13
Dependent Claim
30 words
An air purification system as set forth in claim 11 wherein the passage between the narrow-most section and the outlet turns the air through an arc of approximately 180 degrees.
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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) | 2002-07-19 | 2003-01-18 | 2003-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-07-19 | 2007-01-18 | 2007-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-07-19 | 2011-01-18 | 2011-07-20 | $7700.00 | Window Closed / Lapsed |