US3901794A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circulatory air sifter
Assignee: ThyssenKrupp Industrial Solutions AG
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Filing: 1973-06-25
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Granted: 1975-08-26
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Expires: 1993-06-25
Abstract
Abstract This invention relates to a vertically axised circulatory air sifter having a central sifting chamber for the reception of material to be sifted and an outer annular chamber for fine material separation. A rotary, circulatory fan is disposed above the sifting chamber to establish air circulation through the chambers. At least one cooling air feed inlet communicates with the outer annular chamber and an air outlet communicates with the lower part of the sifter.
Inventors
- 👤 Heinrich Henne
- 👤 Norbert Vorloeper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:35
CPC Classifications
B; B07; B07B; B07B11/00; B07B11/02; B01; B01D; B01D45/00; B01D45/12; B01D45/14; B07B4/00; B07B4/02; B07B4/025; B07B7/00; B07B7/01; B29; B29C; B29C44/00; B29C44/34; B29C44/3415
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
128 words
A VERTICALLY AXISED CIRCULATORY AIR SIFTER CONSTRUCTION COMPRISING AN INNER CYLINDERICAL CASING FORMING A SIFTING CHAMBER, AND OUTER CYLINDERICAL CASING ENCLOSING SAID INNER CASING AND FORMING WITH THE LATTER AN ANNULAR SEPARATION CHAMBER, MEANS FOR INTRODUCING TO SAID SIFTING CHAMBER MATERIAL TO BE SIFTED, FOR MEANS ROTATABLE IN A HORIZONTAL PLANE FOR ESTABLISHING A FLOW OF AIR CIRCUMFERENTIALLY AND DOWNWARDLY THROUGH SAID ANNULAR CHAMBER AND THENCE UPWARDLY THROUGH SAID SIFTING CHAMBER AT LEAST ONE TUBULAR SECONDARY AIR INLET MEMBER HAVING ITS AXIS TANGENTIAL TO SAID ANNULAR CHAMBER AND OPENING DIRECTLY INTO SAID ANNULAR CHAMBER AT A LEVEL BELOW THE PLANE OF ROTATION OF SAID FAN MEANS FOR INTRODUCING COOLING AIR INTO SAID ANNULAR CHAMBER IN A DIRECTION CORRESPONDING TO THE CIRCUMFERENTIAL DIRECTION OFAIR FLOW THROUGH SAID ANNULAR CHAMBER.
Claim 2
Dependent Claim
128 words
A VERTICALLY AXISED CIRCULATORY AIR SIFTER CONSTRUCTION COMPRISING AN INNER CYLINDERICAL CASING FORMING A SIFTING CHAMBER, AND OUTER CYLINDERICAL CASING ENCLOSING SAID INNER CASING AND FORMING WITH THE LATTER AN ANNULAR SEPARATION CHAMBER, MEANS FOR INTRODUCING TO SAID SIFTING CHAMBER MATERIAL TO BE SIFTED, FOR MEANS ROTATABLE IN A HORIZONTAL PLANE FOR ESTABLISHING A FLOW OF AIR CIRCUMFERENTIALLY AND DOWNWARDLY THROUGH SAID ANNULAR CHAMBER AND THENCE UPWARDLY THROUGH SAID SIFTING CHAMBER AT LEAST ONE TUBULAR SECONDARY AIR INLET MEMBER HAVING ITS AXIS TANGENTIAL TO SAID ANNULAR CHAMBER AND OPENING DIRECTLY INTO SAID ANNULAR CHAMBER AT A LEVEL BELOW THE PLANE OF ROTATION OF SAID FAN MEANS FOR INTRODUCING COOLING AIR INTO SAID ANNULAR CHAMBER IN A DIRECTION CORRESPONDING TO THE CIRCUMFERENTIAL DIRECTION OFAIR FLOW THROUGH SAID ANNULAR CHAMBER.
Claim 3
Dependent Claim
20 words
The construction according to claim 1 wherein a plurality of said inlet members are spaced circumferentially of said outer casing.
Claim 4
Dependent Claim
19 words
The construction according to claim 2 wherein there are two of said inlet members diametrically opposed from one another.
Claim 5
Dependent Claim
22 words
The construction according to claim 1 wherein said inlet member has its axis inclined downwardly in the direction of said annular chamber.
Claim 6
Dependent Claim
25 words
The construction according to claim 4 wherein the inclination of the axis of said tubular member is about 10* - 15*with respect to the horizontal.
Claim 7
Dependent Claim
42 words
The construction according to claim 1 wherein said flow of air through said annular chamber is helical and wherein said air inlet member is inclined to the horizontal at an angle corresponding substantially to the helical pitch of said flow of air.
References Cited (Backward Citations)
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US3175686A
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US3349548A
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US3358844A
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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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |