US3713541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screening machine with slotted screen
Assignee: Bird Machine Co Inc
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Filing: 1971-05-10
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Granted: 1973-01-30
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Expires: 1991-05-10
Abstract
Abstract A machine for screening liquid fiber suspension, having a screen with elongated slots disposed along the flow path of the suspension which changes in direction along its length, is made more efficient and plug-free by arranging the slots in at least two areas of the flow path with the long aces of the slots in one area at an angle to the long axes of the slots of the other area such that the slots of said areas have their long axes at substantially a uniform angle, preferably approximately a right angle, to the direction of flow of suspension over them despite difference in said flow direction in the respective areas.
Inventors
- 👤 G Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:59
CPC Classifications
D; D21; D21D; D21D5/00; D21D5/02; D21D5/06; B; B01; B01D; B01D29/00; B01D29/11; B01D29/31; B01D29/35; B01D29/76; B01D29/86; B01D29/88; B01D29/90; B01D29/908; B01D2201/00; B01D2201/18; B01D2201/184
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
207 words
In a screening machine for liquid-fiber suspension having a tubular screen with elongated slots, said screen defining a wall of an annular screening compartment surrounding an axis, an inlet to said compartment adjacent one end of said screen, an outlet adjacent the other end of said screen for suspension rejected by said screen and a separate outlet for suspension passing through said screen, said outlet for rejected suspension having a low capacity relative to said inlet, said inlet arranged to feed suspension into said compartment in a flow which spirals about said axis toward said outlet, the angle of said flow to said axis increasing progressively and substantially as the flow proceeds along said axis, the improvement wherein a first multiplicity of said screen slots adjacent the inlet end of said compartment are arranged substantially parallel to one another and at a substantial angle to a second multiplicity of said screen slots arranged substantially parallel to one another adjacent its outlet end, and said first slots are inclined to said axis at a substantially greater angle than said second slots, said first slots having their ends nearest the inlet further in the direction of flow about said axis tHan their ends nearest the outlet from said compartment.
Claim 2
Dependent Claim
207 words
In a screening machine for liquid-fiber suspension having a tubular screen with elongated slots, said screen defining a wall of an annular screening compartment surrounding an axis, an inlet to said compartment adjacent one end of said screen, an outlet adjacent the other end of said screen for suspension rejected by said screen and a separate outlet for suspension passing through said screen, said outlet for rejected suspension having a low capacity relative to said inlet, said inlet arranged to feed suspension into said compartment in a flow which spirals about said axis toward said outlet, the angle of said flow to said axis increasing progressively and substantially as the flow proceeds along said axis, the improvement wherein a first multiplicity of said screen slots adjacent the inlet end of said compartment are arranged substantially parallel to one another and at a substantial angle to a second multiplicity of said screen slots arranged substantially parallel to one another adjacent its outlet end, and said first slots are inclined to said axis at a substantially greater angle than said second slots, said first slots having their ends nearest the inlet further in the direction of flow about said axis tHan their ends nearest the outlet from said compartment.
Claim 3
Dependent Claim
207 words
In a screening machine for liquid-fiber suspension having a tubular screen with elongated slots, said screen defining a wall of an annular screening compartment surrounding an axis, an inlet to said compartment adjacent one end of said screen, an outlet adjacent the other end of said screen for suspension rejected by said screen and a separate outlet for suspension passing through said screen, said outlet for rejected suspension having a low capacity relative to said inlet, said inlet arranged to feed suspension into said compartment in a flow which spirals about said axis toward said outlet, the angle of said flow to said axis increasing progressively and substantially as the flow proceeds along said axis, the improvement wherein a first multiplicity of said screen slots adjacent the inlet end of said compartment are arranged substantially parallel to one another and at a substantial angle to a second multiplicity of said screen slots arranged substantially parallel to one another adjacent its outlet end, and said first slots are inclined to said axis at a substantially greater angle than said second slots, said first slots having their ends nearest the inlet further in the direction of flow about said axis tHan their ends nearest the outlet from said compartment.
Claim 4
Dependent Claim
207 words
In a screening machine for liquid-fiber suspension having a tubular screen with elongated slots, said screen defining a wall of an annular screening compartment surrounding an axis, an inlet to said compartment adjacent one end of said screen, an outlet adjacent the other end of said screen for suspension rejected by said screen and a separate outlet for suspension passing through said screen, said outlet for rejected suspension having a low capacity relative to said inlet, said inlet arranged to feed suspension into said compartment in a flow which spirals about said axis toward said outlet, the angle of said flow to said axis increasing progressively and substantially as the flow proceeds along said axis, the improvement wherein a first multiplicity of said screen slots adjacent the inlet end of said compartment are arranged substantially parallel to one another and at a substantial angle to a second multiplicity of said screen slots arranged substantially parallel to one another adjacent its outlet end, and said first slots are inclined to said axis at a substantially greater angle than said second slots, said first slots having their ends nearest the inlet further in the direction of flow about said axis tHan their ends nearest the outlet from said compartment.
Claim 5
Dependent Claim
20 words
A screening machine according to claim 1 wherein said angle of said first slots to said axis is about 45*.
Claim 6
Dependent Claim
17 words
A screening machine according to claim 1 wherein said second slots are substantially parallel to said axis.
Claim 7
Dependent Claim
22 words
A screening machine according to claim 1 which includes a pulsing means spaced opposite said screen and rotatable about said compartment axis.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |