← Back to Patent Explorer
US3977515A Expired / Lapsed US ⏱️ 0.0 years remaining

Hard-surfaced screw conveyor for centrifuges

Assignee: Bird Machine Co Inc
•
Filing: 1974-12-16
•
Granted: 1976-08-31
•
Expires: 1994-12-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

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)

US3123187A Cited
CH36323A 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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag