Patent US4435122A successfully refreshed from Google Patents.
US4435122A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for pumping fiber suspensions
Assignee: KAMYR KNUT DAHLS VAG AB
•
Filing: 1981-03-02
•
Granted: 1984-03-06
•
Expires: 2001-03-02
Abstract
Abstract The disclosure describes a method and a device for pumping fiber suspensions of high consistency. Shear forces disrupting fiber flocs are induced near the front edge of the vanes of the impeller in a centrifugal pump which fluidize the fiber suspension hereby converting it into an easily pumpable state. This is effected by an inlet part having recesses and/or lobes in its inner surface in front of the impeller which cooperate with a rotor having an outer surface in which there are recesses and/or lobes disposed into the inlet part.
Inventors
- 👤 Toivo Niskanen
- 👤 Frey Sundman
- 👤 Jorma Tuomaala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:40
CPC Classifications
F; F04; F04D; F04D7/00; F04D7/02; F04D7/04; F04D7/045; F05; F05B; F05B2210/00; F05B2210/10; F05B2210/13; F05B2210/132
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
134 words
A method of fluidizing and pumping a fiber suspension with a centrifugal pump in the fluidized state; said pump having an inlet which has a conduit; a housing, an impeller with vames, an outlet and a non-round rotor which is located in the inlet of the pump, the inlet having recesses on its surface, which comprises feeding said fiber suspension into the conduit of the inlet; causing the rotor to rotate, bringing the fiber suspension into rotating motion in the inlet of the pump, said rotating motion having alternate flow components towards and away from the rotation axis of the rotor whereby shear forces are generated in the inlet of the pump which disrupt the fiber-to-fiber bonds whereby the fiber suspension is fludized, becomes pumpable and flows to the impeller in a fluidized state.
Claim 2
Independent Claim
134 words
A method of fluidizing and pumping a fiber suspension with a centrifugal pump in the fluidized state; said pump having an inlet which has a conduit; a housing, an impeller with vames, an outlet and a non-round rotor which is located in the inlet of the pump, the inlet having recesses on its surface, which comprises feeding said fiber suspension into the conduit of the inlet; causing the rotor to rotate, bringing the fiber suspension into rotating motion in the inlet of the pump, said rotating motion having alternate flow components towards and away from the rotation axis of the rotor whereby shear forces are generated in the inlet of the pump which disrupt the fiber-to-fiber bonds whereby the fiber suspension is fludized, becomes pumpable and flows to the impeller in a fluidized state.
Claim 3
Dependent Claim
75 words
A pump for fluidizing a fiber suspension and pumping the fiber suspension in the fluidized state which comprises an inlet having a non-circular cross-section, and recesses in the inlet, the cross-section of the inlet alternately decreasing and increasing, a housing, an outlet, an impeller having impeller vanes and means located in the inlet for subjecting the fiber suspension to shear forces in the inlet, which means comprise a rotor, said rotor having a non-round cross-section.
Claim 4
Dependent Claim
75 words
A pump for fluidizing a fiber suspension and pumping the fiber suspension in the fluidized state which comprises an inlet having a non-circular cross-section, and recesses in the inlet, the cross-section of the inlet alternately decreasing and increasing, a housing, an outlet, an impeller having impeller vanes and means located in the inlet for subjecting the fiber suspension to shear forces in the inlet, which means comprise a rotor, said rotor having a non-round cross-section.
References Cited (Backward Citations)
AT176507B
Cited
PL45412B1
Cited
DE1211905B
Cited
US3316848A
Cited
US3973866A
Cited
DE2818540B2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-06 | 1987-09-05 | 1988-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-06 | 1991-09-05 | 1992-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-06 | 1995-09-05 | 1996-03-06 | $7700.00 | Window Closed / Lapsed |