US3581893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screening apparatus
Assignee: Improved Machinery Inc
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Filing: 1970-01-09
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Granted: 1971-06-01
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Expires: 1990-01-09
Abstract
Abstract Screening apparatus of the type employed for screening pulp stock wherein diluent fluid is supplied adjacent the accepted stock face of the screen for diluting the accepted stock and causing it to flow in a direction counter to the flow of stock along the feed face of the screen.
Inventors
- 👤 John P Rich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:55
CPC Classifications
B; B01; B01D; B01D29/00; B01D29/01; B01D29/03; B01D29/11; B01D29/31; B01D29/33; B01D29/336; B01D29/62; B01D29/66; B01D29/666; B01D29/70; B01D29/72; B01D29/76; B01D29/78; B01D29/88; B01D29/90; B01D29/94; B01D29/945; B01D2201/00; B01D2201/28; B01D2201/282
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
258 words
An apparatus for screening pulp stock, comprising a screen having feed and accepts faces and screening apertures extending from said feed face to said accepts face, stock supply means at one end of said screen communicating with a source of pulp stock and operatively associated with said screen for supplying pulp stock to said feed face at said one end of said screen, rejected stock discharge means at the other end of said screen communicating with said stock supply means for discharging stock rejected by said screening apertures from said feed face at the other end of said screen, wall means extending along said accepts face cooperating therewith to bound a passage which extends continuously along said accepts face in communication with said screening apertures to receive accepted stock therefrom, dilution liquid supply means communicating with a source of dilution liquid and connected to said passage at said other end of said screen independently of said screening apertures for supplying dilution liquid to said passage at said other end of the screen, said wall means directing such dilution liquid through said passage along said accepts face towards said one end of said screen whereby the dilution liquid intermixes with accepted stock in said passage to cause such accepted stock to flow along said accepts face towards said one end of said screen, and accepted stock discharge means connected to said passage at said one end of said screen for discharging the mixture of dilution liquid and accepted stock from said passage at said one end of said screen.
Claim 2
Independent Claim
258 words
An apparatus for screening pulp stock, comprising a screen having feed and accepts faces and screening apertures extending from said feed face to said accepts face, stock supply means at one end of said screen communicating with a source of pulp stock and operatively associated with said screen for supplying pulp stock to said feed face at said one end of said screen, rejected stock discharge means at the other end of said screen communicating with said stock supply means for discharging stock rejected by said screening apertures from said feed face at the other end of said screen, wall means extending along said accepts face cooperating therewith to bound a passage which extends continuously along said accepts face in communication with said screening apertures to receive accepted stock therefrom, dilution liquid supply means communicating with a source of dilution liquid and connected to said passage at said other end of said screen independently of said screening apertures for supplying dilution liquid to said passage at said other end of the screen, said wall means directing such dilution liquid through said passage along said accepts face towards said one end of said screen whereby the dilution liquid intermixes with accepted stock in said passage to cause such accepted stock to flow along said accepts face towards said one end of said screen, and accepted stock discharge means connected to said passage at said one end of said screen for discharging the mixture of dilution liquid and accepted stock from said passage at said one end of said screen.
Claim 3
Dependent Claim
28 words
A screening apparatus according to claim 1, wherein said screen is a flat screen and said wall means includes means operable for pulsing the mixture in said passage.
Claim 4
Dependent Claim
24 words
A screening apparatus according to claim 1, wherein said screen is annular, and said wall means is also annular whereby said passage is annular.
Claim 5
Dependent Claim
54 words
A screening apparatus according to claim 1, wherein said screen is annular with said feed and accepts faces being the outer and inner faces of said screen, respectively, said wall means is annular and disposed within said screen whereby said passage is annular, and means are provided for pulsing the mixture in said passage.
Claim 6
Dependent Claim
26 words
A screening apparatus according to claim 4, wherein said pulsing means is carried by said wall means and said wall means and screen are relatively rotatable.
Claim 7
Independent Claim
246 words
An apparatus for screening pulp stock, comprising a screen having feed and accepts faces and screening apertures extending therebetween, stock supply means communicating with a source of pulp stock and operatively associated with said sCreen for supplying pulp stock to said feed face at one end of said screen, first discharge means operatively associated with said screen and communicating with said stock supply means for discharging stock rejected by said screening apertures from said feed face at the other end of said screen, second discharge means operatively associated with said screen for discharging accepted stock from adjacent said accepts face at said one end of said screen, dilution liquid supply means communicating with a source of dilution liquid and on the accepts side of said screen for supplying dilution liquid to said accepts face at said other end of said screen independently of said screening apertures, and means extending along said screen bounding a space which extends continuously along said accepts face from said one end of said screen to said other end thereof, said space communicating with said screening apertures to receive stock accepted thereby and said space connecting said dilution liquid supply means with said second discharge means whereby dilution liquid supplied to said dilution liquid supply means flows along said accepts face towards said one end of said screen and intermixes with accepted stock in said space to cause such accepted stock to flow along said accepts face to said second discharge means.
Claim 8
Independent Claim
246 words
An apparatus for screening pulp stock, comprising a screen having feed and accepts faces and screening apertures extending therebetween, stock supply means communicating with a source of pulp stock and operatively associated with said sCreen for supplying pulp stock to said feed face at one end of said screen, first discharge means operatively associated with said screen and communicating with said stock supply means for discharging stock rejected by said screening apertures from said feed face at the other end of said screen, second discharge means operatively associated with said screen for discharging accepted stock from adjacent said accepts face at said one end of said screen, dilution liquid supply means communicating with a source of dilution liquid and on the accepts side of said screen for supplying dilution liquid to said accepts face at said other end of said screen independently of said screening apertures, and means extending along said screen bounding a space which extends continuously along said accepts face from said one end of said screen to said other end thereof, said space communicating with said screening apertures to receive stock accepted thereby and said space connecting said dilution liquid supply means with said second discharge means whereby dilution liquid supplied to said dilution liquid supply means flows along said accepts face towards said one end of said screen and intermixes with accepted stock in said space to cause such accepted stock to flow along said accepts face to said second discharge means.
Claim 9
Dependent Claim
30 words
A screening apparatus according to claim 6, wherein said screen is a flat screen, and said feed and accepts faces are the upper and lower faces, respectively, of said screen.
Claim 10
Dependent Claim
14 words
A screening apparatus according to claim 6, wherein said screen and space are annular.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |