US4391561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solids pumping apparatus
Assignee: Combustion Engineering Inc
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Filing: 1981-04-13
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Granted: 1983-07-05
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Expires: 2001-04-13
Abstract
Abstract A pump for feeding granular material into a pressurized zone having a feed screw (14) located within a cylinder (12). The cylinder is tapered (34) at its discharge end, and the outside diameter of the flights (32) is also tapered (43). The clearance (38) of the tapered flights is significantly greater than the clearance (40) of the non-tapered flights.
Inventors
- 👤 Donald A. Smith
- 👤 Bruce M. Pote
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:22
CPC Classifications
B; B65; B65G; B65G53/00; B65G53/34; B65G53/40; B65G53/48
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
189 words
An apparatus for feeding a granular material into a pressurized zone comprising: a stationary hollow cylinder having a bore; a frustoconical reducing nozzle located at a discharge end of said cylinder; means for feeding the granular material into said cylinder at an upstream located of said cylinder; a rotary feeder screw concentrically located within said cylinder and having helical flights thereon, said flights having a decreasing pitch towards the discharge end; means for rotating said feed screw at high speeds; said flights having an OD only slightly less than said bore through a majority of the length of said feed screw, and having a tapered decreasing OD at the discharge end, the taper being at least as great as that of said nozzle; said feed screw being located within said cylinder such that the radial clearance between the nozzle bore and the tapered flights is significantly greater than that between the bore of the cylinder and the flights through the majority of length, and the tapered flight extending through only a portion of said nozzle; and a columnar plug rotating with said screw and concentrically located with said nozzle.
Claim 2
Independent Claim
189 words
An apparatus for feeding a granular material into a pressurized zone comprising: a stationary hollow cylinder having a bore; a frustoconical reducing nozzle located at a discharge end of said cylinder; means for feeding the granular material into said cylinder at an upstream located of said cylinder; a rotary feeder screw concentrically located within said cylinder and having helical flights thereon, said flights having a decreasing pitch towards the discharge end; means for rotating said feed screw at high speeds; said flights having an OD only slightly less than said bore through a majority of the length of said feed screw, and having a tapered decreasing OD at the discharge end, the taper being at least as great as that of said nozzle; said feed screw being located within said cylinder such that the radial clearance between the nozzle bore and the tapered flights is significantly greater than that between the bore of the cylinder and the flights through the majority of length, and the tapered flight extending through only a portion of said nozzle; and a columnar plug rotating with said screw and concentrically located with said nozzle.
Claim 3
Dependent Claim
28 words
An apparatus as in claim 1 wherein the length of the tapered portion of the flights is greater than 40 percent of the inside diameter of the bore.
Claim 4
Dependent Claim
28 words
An apparatus as in claim 2 wherein the length of the tapered portion of the flights is less than 60 percent of the inside diameter of the bore.
Claim 5
Independent Claim
36 words
An apparatus as in any one of claims 1 through 3 wherein the radial clearance of the tapered flights within the nozzle is greater than two times the clearance of the non-tapered flights within the bore.
Claim 6
Dependent Claim
30 words
An apparatus as in claim 4 wherein the clearance between the tapered flights and the nozzle is greater than four times the clearance of the non-tapered flights within the bore.
Claim 7
Independent Claim
17 words
An apparatus as in any one of claims 1 through 3 wherein said columnar plug is cylindrical.
Claim 8
Dependent Claim
12 words
An apparatus as in claim 5 wherein said columnar plug is cylindrical.
Claim 9
Independent Claim
37 words
An apparatus as in any one of claims 1 through 3 wherein the radial clearance between the tapered flights and the nozzle is greater than three times the largest particle size of the material to be fed.
Claim 10
Independent Claim
28 words
An apparatus as in any one of claims 1 through 3 wherein the angle of the taper of the flights equals the angle of taper of the nozzle.
Claim 11
Dependent Claim
23 words
An apparatus as in claim 5 wherein the angle of the taper of the flights equals the angle of taper of the nozzle.
Claim 12
Independent Claim
36 words
An apparatus as in any one of claims 1 through 3 wherein the taper of the flights equals the taper of the nozzle, and wherein said columnar plug is a cylindrical extension of said feed screw.
Claim 13
Dependent Claim
23 words
An apparatus as in claim 5 wherein the angle of the taper of the flights equals the angle of taper of the nozzle.
References Cited (Backward Citations)
US3093419A
Cited
SU197708A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-04 | 1987-01-03 | 1987-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-04 | 1991-01-03 | 1991-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-04 | 1995-01-03 | 1995-07-05 | $7700.00 | Window Closed / Lapsed |