US4378165A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Draft tube apparatus
Assignee: SPX Technologies Inc
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Filing: 1980-12-30
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Granted: 1983-03-29
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Expires: 2000-12-30
Abstract
Abstract Improved draft tube mixing apparatus having one or more of the following features: (a) controlled circulation at the inlet of the tube which allows operation at reduced submergence by preventing formation of a vortex; (b) an additional passage for controlled flow into the draft tube along its length to allow operation without the tube being entirely submerged; (c) the recovery of dynamic energy from the flow at the outlet of the tube by wide area diffusion without separation from the walls of the tube in the diffusing region thereof; (d) improved guidance of radially directed to axially directed flow at the inlet of the draft tube for efficient axial pumping by the impeller by maintaining generally uniform axial flow velocity radially of the impeller; and (e) separation of coarse and fine particles in suspension in the tank to allow selective draw-off of the coarse and/or fine particles thereby increasing efficiency of mixing.
Inventors
- 👤 George G. Landberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:31
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/1278; C02F3/1284; B; B01; B01F; B01F27/00; B01F27/80; B01F27/91; B01F27/05; B01F27/11; B01F27/15; Y; Y02; Y02P; Y02P70/00; Y02P70/10; Y02W; Y02W10/00; Y02W10/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
84 words
For use in a mixing apparatus having a tank for containing liquid, draft tube apparatus comprising a draft tube in the tank and an impeller disposed in said draft tube for circulating the liquid from said tank along a flow path through said tube, a member disposed in said tank and having a mass such that it floats at the surface of said liquid, and means for maintaining said member in said flow path to control the flow of said liquid through said tube.
Claim 2
Dependent Claim
84 words
For use in a mixing apparatus having a tank for containing liquid, draft tube apparatus comprising a draft tube in the tank and an impeller disposed in said draft tube for circulating the liquid from said tank along a flow path through said tube, a member disposed in said tank and having a mass such that it floats at the surface of said liquid, and means for maintaining said member in said flow path to control the flow of said liquid through said tube.
Claim 3
Dependent Claim
25 words
The invention as set forth in claim 1 wherein said maintaining means includes means for locating said member over one end of said draft tube.
Claim 4
Dependent Claim
25 words
The invention as set forth in claim 2 wherein said one end is the inlet end of said draft tube into which said liquid flows.
Claim 5
Dependent Claim
25 words
The invention as set forth in claim 3 wherein said member is a body having a periphery shaped like the pheriphery of said draft tube.
Claim 6
Dependent Claim
30 words
The invention as set forth in claim 3 wherein said member is annular in shape and is of outer diameter approximately equal to the inner diameter of said draft tube.
Claim 7
Dependent Claim
34 words
The invention as set forth in claim 5 wherein said impeller has a drive shaft extending through the surface of said liquid and said annular member is a ring through which said shaft extends.
Claim 8
Dependent Claim
30 words
The invention as set forth in claim 6 wherein said ring has a plurality of radially disposed vanes extending from the side thereof facing the inlet of said draft tube.
Claim 9
Dependent Claim
23 words
The invention as set forth in claim 7 wherein said maintaining means includes means for locating said ring coaxial with said draft tube.
Claim 10
Dependent Claim
78 words
The invention as set forth in claim 8 wherein struts are provided for supporting said draft tube, said struts extending vertically from said tank into said tank, said one of said ring and struts having key ways and the other having keys, said keys projecting radially into said key ways whereby said ring is guided by said keys and key ways as the axial position thereof changes in the level of said liquid in which said ring floats.
Claim 11
Dependent Claim
56 words
The invention as set forth in claim 6 wherein said ring is a disc having a hole in the center thereof of diameter greater than the diameter of said drive shaft, the outer periphery of said ring being of a diameter equal to or less than the diameter of the inlet end of said draft tube.
Claim 12
Dependent Claim
42 words
The invention as set forth in claim 3 wherein said member has a vane extending from the side of said member facing the inlet of said draft tube, said vane being disposed radially with respect to the axis of said draft tube.
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) | 1986-03-28 | 1986-09-27 | 1987-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-28 | 1990-09-27 | 1991-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-28 | 1994-09-27 | 1995-03-29 | $7700.00 | Window Closed / Lapsed |