US3977515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hard-surfaced screw conveyor for centrifuges
Assignee: Bird Machine Co Inc
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Filing: 1974-12-16
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Granted: 1976-08-31
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Expires: 1994-12-16
Abstract
Abstract A hard-surfaced screw conveyor for centrifuges has a helical metal blade with a plurality of wear-resisting segments mounted on one side thereof, there being mating parts on the opposed surfaces of the segments and the blade which are slidably interengaged to prevent radial outward and axial relative movements of the segments and the blade.
Inventors
- 👤 Elwin J. Lewoczko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:07
CPC Classifications
B; B65; B65G; B65G33/00; B65G33/24; B65G33/26; B65G33/265; B04; B04B; B04B1/00; B04B1/20; B04B1/2008; F; F16; F16B; F16B2200/00; F16B2200/30; Y; Y10; Y10T; Y10T403/00; Y10T403/70; Y10T403/7018
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
190 words
A hard surfaced screw conveyor for centrifuges comprising: a helical metal blade mounted for rotation about the longitudinal axis of the helix and having radially disposed side surfaces extending to an end surface; a plurality of wear resistant segments mounted on a surface of the blade, said segment and said blade surface provided with mating parts wedged together to mount said segments on said blade and to permit movement thereof only in the radially inward direction toward the blade axis; keeper means retaining said segments against such radially inward movement; and said segments including a first set which are wider at their radially outer than their radially inner ends, and a second set intervening segments of said first set having a different shape with side edges parallel to the opposed side edges of the segments of said first set at opposite sides thereof, so that, upon removal of said keeper means, segments of said second set can be removed by sliding radially inwardly of said blade surface, and segments of said first set can be similarly removed after removal of a segment of said second set at one side thereof.
Claim 2
Dependent Claim
190 words
A hard surfaced screw conveyor for centrifuges comprising: a helical metal blade mounted for rotation about the longitudinal axis of the helix and having radially disposed side surfaces extending to an end surface; a plurality of wear resistant segments mounted on a surface of the blade, said segment and said blade surface provided with mating parts wedged together to mount said segments on said blade and to permit movement thereof only in the radially inward direction toward the blade axis; keeper means retaining said segments against such radially inward movement; and said segments including a first set which are wider at their radially outer than their radially inner ends, and a second set intervening segments of said first set having a different shape with side edges parallel to the opposed side edges of the segments of said first set at opposite sides thereof, so that, upon removal of said keeper means, segments of said second set can be removed by sliding radially inwardly of said blade surface, and segments of said first set can be similarly removed after removal of a segment of said second set at one side thereof.
Claim 3
Dependent Claim
24 words
A conveyor according to claim 1 wherein said parts on said blade are welded thereto and said parts on said segments are molded therein.
Claim 4
Dependent Claim
14 words
A conveyor according to claim 2 wherein said segments are formed of ceramic material.
Claim 5
Dependent Claim
21 words
A conveyor according to claim 1 wherein said segments and said parts extend to the radially outer end of said blade.
Claim 6
Dependent Claim
33 words
A conveyor according to claim 1 wherein said parts comprise a pair of tongues and a pair of grooves extending generally radially outwardly of the conveyor axis at an angle to each other.
Claim 7
Dependent Claim
22 words
A conveyor according to claim 5 wherein said grooves are formed at the sides of wedge-shaped metal pieces welded to said conveyor.
Claim 8
Dependent Claim
30 words
A conveyor according to claim 6 wherein a said metal piece is disposed between each contiguous pair of said segments with its larger end disposed radially outwardly of said helix.
Claim 9
Dependent Claim
23 words
A conveyor according to claim 1 wherein said keeper means includes keepers attached to said blade at the inner ends of said segments.
References Cited (Backward Citations)
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Cited
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Cited
US1284752A
Cited
US2415033A
Cited
US2434935A
Cited
US3216219A
Cited
US3764062A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |