US4880530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-cleaning screening device
Assignee: Individual
•
Filing: 1988-07-05
•
Granted: 1989-11-14
•
Expires: 2008-07-05
Abstract
Abstract The invention comprises a screening device for separating fine particles from a stream of air and a particulate mixture containing coarse and fines which includes a box-like hollow housing tilted downwardly at an acute angle. The housing contains a plurality of elongated screening elements and an air cleaning device consisting of a blowpipe and a series of nozzles directed at the screening elements through Venturi tubes. At periodic intervals a jet or pulse of air is injected into the Venturi tubes to reverse air flow and rid the screen elements of adhered coarse particles. Substantially complete fines removal can be achieved by employing a recycling loop between the coarse particle outlet and inlet of the housing.
Inventors
- 👤 Robert E. Frey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:50
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/02; B01D46/04; B01D46/42; B01D46/4281; B01D46/52; B01D46/521; B01D46/66; B01D46/70; B01D46/71; B07; B07B; B07B1/00; B07B1/46; B07B1/50; B07B1/55; B07B11/00; B07B11/08; B07B7/00; B07B7/06; B01D2275/00; B01D2275/20; B01D2275/201
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
147 words
An apparatus for continuously separating a mixture of fine and coarse particles comprising: (a) a hollow housing having a tubesheet located therein tilted downwardly at an acute angle from the horizontal, said tubesheet separating said housing into a lower fines outlet chamber and an upper pre-screen chamber; (b) a plurality of Venturi tubes mounted on said tubesheet; (c) a plurality of screen elements mounted on said Venturi tubes; (d) means located in said fines outlet chamber for introducing a pulse of a compressed gas through said Venturi tubes to the screens; (e) an inlet for introducing air and said mixture of fine and coarse particles to said pre-screen chamber mounted in said housing; (f) an outlet for coarse particles mounted on said housing and communicating with said pre-screen chamber; and (g) an outlet for fine particles mounted in said housing and communicating with said fines outlet chamber.
Claim 2
Independent Claim
147 words
An apparatus for continuously separating a mixture of fine and coarse particles comprising: (a) a hollow housing having a tubesheet located therein tilted downwardly at an acute angle from the horizontal, said tubesheet separating said housing into a lower fines outlet chamber and an upper pre-screen chamber; (b) a plurality of Venturi tubes mounted on said tubesheet; (c) a plurality of screen elements mounted on said Venturi tubes; (d) means located in said fines outlet chamber for introducing a pulse of a compressed gas through said Venturi tubes to the screens; (e) an inlet for introducing air and said mixture of fine and coarse particles to said pre-screen chamber mounted in said housing; (f) an outlet for coarse particles mounted on said housing and communicating with said pre-screen chamber; and (g) an outlet for fine particles mounted in said housing and communicating with said fines outlet chamber.
Claim 3
Dependent Claim
11 words
The apparatus of claim 1 wherein said angle is about 45°.
Claim 4
Dependent Claim
13 words
The apparatus of claim 1 wherein said screen elements are conical screen elements.
Claim 5
Dependent Claim
12 words
The apparatus of claim 3 wherein said conical screen elements are pleated.
Claim 6
Dependent Claim
11 words
The apparatus of claim 1 wherein said screen elements are cylindrical.
Claim 7
Dependent Claim
21 words
The apparatus of claim 1 wherein said hollow housing is a box and said screen elements are arranged in rows therein.
Claim 8
Dependent Claim
10 words
The apparatus of claim 3 wherein said housing is cylindrical.
Claim 9
Dependent Claim
18 words
The apparatus of claim 7 wherein said inlet is mounted tangentially in the top portion of said housing.
Claim 10
Dependent Claim
22 words
The apparatus of claim 1 wherein said screen elements are planar and carried on more than one side of a rectangular member.
Claim 11
Dependent Claim
16 words
The apparatus of claim 1 wherein said inlet is mounted at the top of said housing.
Claim 12
Dependent Claim
16 words
The apparatus of claim 1 wherein said inlet is mounted at the bottom of said housing.
Claim 13
Dependent Claim
21 words
The apparatus of claim 1 which further comprises a recirculating duct extending from said outlet for coarse particles to said inlet.
Claim 14
Dependent Claim
21 words
The apparatus of claim 12 wherein a container for mixture of fine and coarse particles is connected with said recirculating duct.
Claim 15
Dependent Claim
26 words
The apparatus of claim 1 which further comprises a baffle in said housing for directing said mixture of fine and coarse particles to said screen elements.
Claim 16
Independent Claim
137 words
An apparatus for continuously separating a mixture of fine and coarse particles comprising: (a) a hollow housing having a tubesheet located therein, said tubesheet separating said housing into a fines outlet chamber and a pre-screen chamber; (b) a plurality of Venturi tubes mounted on said tubesheet; (c) a plurality of screen elements mounted on said Venturi tubes; (d) means located in said fines outlet chamber for introducing a pulse of a compressed gas through said Venturi tubes to the screen elements; (e) an inlet for introducing air and said mixture of fine and coarse particles to said pre-screen chamber mounted in said housing; (f) an outlet for coarse particles mounted on said housing and communicating with said pre-screen chamber; and (g) an outlet for fine particles mounted in said housing and communicating with said fines outlet chamber.
Claim 17
Independent Claim
137 words
An apparatus for continuously separating a mixture of fine and coarse particles comprising: (a) a hollow housing having a tubesheet located therein, said tubesheet separating said housing into a fines outlet chamber and a pre-screen chamber; (b) a plurality of Venturi tubes mounted on said tubesheet; (c) a plurality of screen elements mounted on said Venturi tubes; (d) means located in said fines outlet chamber for introducing a pulse of a compressed gas through said Venturi tubes to the screen elements; (e) an inlet for introducing air and said mixture of fine and coarse particles to said pre-screen chamber mounted in said housing; (f) an outlet for coarse particles mounted on said housing and communicating with said pre-screen chamber; and (g) an outlet for fine particles mounted in said housing and communicating with said fines outlet chamber.
Claim 18
Dependent Claim
17 words
The apparatus of claim 15 where the tubesheet is tilted at an acute angle from the horizontal.
Claim 19
Dependent Claim
16 words
The apparatus of claim 16 where the screen elements are at an angle to the horizontal.
Claim 20
Dependent Claim
28 words
The apparatus of claim 16 where the fines outlet chamber has a bottom wall at an angle to the horizontal and the prescreen chamber is above the tubesheet.
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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) | 1992-11-13 | 1993-05-15 | 1993-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-13 | 1997-05-15 | 1997-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-13 | 2001-05-15 | 2001-11-14 | $7700.00 | Window Closed / Lapsed |