US4043920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Skimmer for square settling tanks
Assignee: Dorr Oliver Inc
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Filing: 1976-08-25
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Granted: 1977-08-23
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Expires: 1996-08-25
Abstract
Abstract In a continuously operating square settling tank, the provision of scum skimming devices wherein a pivotally mounted corner exploring skimmer member is swingable in a predetermined horizontal plane, while kept in contact with the peripheral scum baffle during rotation of the supporting rake structure. This skimmer member forms with the scum baffle a scum collecting pocket whereby when the thus collected scum is pushed up along the slope of a ramp, it is trapped and thereby contained on the ramp for delivery into a receiving box connected to the ramp. The scum collecting effectiveness of the skimmer member may be enhanced by the additional provision of a directional skimmer blade cooperatively so related to the swingable skimmer member, that floating scum material is thereby guided into said collecting pocket.
Inventors
- 👤 Thomas Wooh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:14
CPC Classifications
B; B01; B01D; B01D21/00; B01D21/10; B01D21/12; B01D21/14; B01D21/18; B01D21/24; B01D21/2427; B01D21/2433
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
248 words
In a square type continuously operating settling tank having a central feed supply, a four-sided overflow launder extending along the periphery of the tank, defining the overflow level for supernatant liquid separated from sludge settled on the tank bottom, sludge outlet means in the tank bottom, and a rotary rake structure having rake arms effective to move sludge over the tank bottom to said outlet means, the combination which comprises a four-sided scum baffle having rounded corners, cooperating with the overflow launder in arresting floating scum, a post rising vertically from a rake arm of said raking structure, an horizontal skimmer arm structure turnably supported by said post for swinging movement in an horizontal plane, a scum engaging skimmer member carried by said arm structure unitary therewith and shaped to form with the scum baffle a scum collecting pocket, said skimmer member having a resiliently deflectable bottom edge portion, pressure means for urging said skimmer member into cooperative contact with said scum baffle, so as to form therewith said scum collecting pocket, a scum receiving box located at one side of said scum baffle, and a ramp connected to the inlet side of the box, said ramp and said skimmer member being constructed and arranged for cooperation with one another so that the scum collected in said pocket is trapped between said skimmer member and said ramp while being moved up the ramp and into said receiving box by said deflectable bottom edge portion of the skimmer member.
Claim 2
Dependent Claim
248 words
In a square type continuously operating settling tank having a central feed supply, a four-sided overflow launder extending along the periphery of the tank, defining the overflow level for supernatant liquid separated from sludge settled on the tank bottom, sludge outlet means in the tank bottom, and a rotary rake structure having rake arms effective to move sludge over the tank bottom to said outlet means, the combination which comprises a four-sided scum baffle having rounded corners, cooperating with the overflow launder in arresting floating scum, a post rising vertically from a rake arm of said raking structure, an horizontal skimmer arm structure turnably supported by said post for swinging movement in an horizontal plane, a scum engaging skimmer member carried by said arm structure unitary therewith and shaped to form with the scum baffle a scum collecting pocket, said skimmer member having a resiliently deflectable bottom edge portion, pressure means for urging said skimmer member into cooperative contact with said scum baffle, so as to form therewith said scum collecting pocket, a scum receiving box located at one side of said scum baffle, and a ramp connected to the inlet side of the box, said ramp and said skimmer member being constructed and arranged for cooperation with one another so that the scum collected in said pocket is trapped between said skimmer member and said ramp while being moved up the ramp and into said receiving box by said deflectable bottom edge portion of the skimmer member.
Claim 3
Dependent Claim
79 words
The settling tank according to claim 1, wherein said skimmer member is constructed and arranged relative to the corner curvature of the scum baffle, so that the line represented by the radial distance between the point of contact of the skimmer member with the scum baffle and said post, forms with a tangent on said curvature at the point of said contact an enclosed angle such as to insure unobstructed contact of said skimmer member along with scum baffle.
Claim 4
Dependent Claim
82 words
The settling tank according to claim 1, with the addition of a stem extending vertically downward from said skimmer arm structure parallel and adjacent to said post, means for maintaining said stem in said parallel position, vertical thrust bearing means connected to said post, for supportively engaging the lower end of said stem, and adjusting means cooperatively associated with said vertical thrust bearing means, and operable to axially adjust said stem, whereby said skimmer arm structure is adjustably movable parallel to itself.
Claim 5
Dependent Claim
57 words
The settling tank according to claim 1, with the addition of a scum engaging skimmer blade carried by said skimmer arm structure, and extending into cooperative relationship with the rear end portion of said skimmer member, such that floating scum material is guided by said skimmer blade into said collecting pocket during rotation of said raking structure.
Claim 6
Dependent Claim
35 words
The settling tank according to claim 1, wherein said skimmer member is constructed and arranged so that the outer end portion thereof will constitute with the scum baffle an enclosed angle not greater than 90°.
Claim 7
Dependent Claim
75 words
The settling tank according to claim 1, wherein said post is fixedly connected to said rake structure, with the addition of a stem extending downward from said skimmer arm structure fixed thereto, a pair of vertically spaced bearings for the stem, connected to said post, and a vertical thrust bearing connected to said post, and supportively engaging the lower end portion of said stem, and means for vertically adjusting said thrust bearing on said post.
Claim 8
Dependent Claim
17 words
The settling tank according to claim 2, wherein said enclosed angle is about 10° smaller than 90°.
Claim 9
Dependent Claim
65 words
The settling tank according to claim 1, wherein said skimmer member is of generally concave shape facing towards the scum baffle, with the addition of connecting means for adjustably fixing the skimmer member to said skimmer arm, operable so as to adjust the position of said skimmer member in a horizontal plane relative to said skimmer arm as well as relative to said scum baffle.
Claim 10
Dependent Claim
58 words
The settling tank according to claim 1, wherein said skimmer member is of generally concave shape facing towards the scum baffle, and having an outer shank portion engaging the scum baffle, and an inner shank portion, with the addition of means for fixing the skimmer member to the underside of said skimmer structure at the respective shank portions.
Claim 11
Dependent Claim
81 words
The settling tank according to claim 1, wherein said skimmer member is of generally concave shape facing towards the scum baffle, comprising an outer shank portion engaging the scum baffle, and an inner shank portion, with the addition of first means for connecting said outer shank portion to the outer end portion of said skimmer arm structure, and second means for connecting said inner shank portion to said skimmer arm structure at a point spaced inwardly from said first connecting means.
Claim 12
Dependent Claim
120 words
The settling tank according to claim 1, with the addition of a scum engaging skimmer blade carried by said skimmer arm structure, and extending into cooperative relationship with the rear end portion of said skimmer member, such that floating scum material is guided by said skimmer blade towards said collecting pocket during rotation of said raking structure, the outer end of said skimmer blade having attached thereto a vertical flexible flap of resiliently deflectable material, arranged to provide a sealing relationship with said inner end of the skimmer member, said flap furthermore adapted to be deflected by the respective side of said ramp and of said scum receiving box incident to said skimmer member overriding said ramp and said box.
Claim 13
Dependent Claim
94 words
The settling tank according to claim 1, wherein said skimmer arm structure comprises an outer end portion carrying said skimmer member, and an inner end portion extending in the opposite direction from the vertical axis of rotation of the skimmer member, and wherein said pressure means comprise a bracket arm extending radially from said post and in a direction such as to provide an anchoring point, and tension means efffective between said anchoring point and said inner end portion of said skimmer arm for maintaining said skimmer member in contact with said scum baffle.
Claim 14
Dependent Claim
197 words
The settling tank according to claim 1, wherein said post is fixedly connected to said rake structure, with the addition of a vertical stem extending downwardly from said skimmer member and parallel to said post, bearing means for mounting said stem in vertical position and turnable on said post, said bearing means comprising a pair of vertically spaced bearings for the stem, connected to said post, and vertical thrust bearing means connected to said post and supportively engaging the lower end of said stem, and means for vertically adjusting said thrust bearing on said post, with the addition of a non-swingable and scum engaging skimmer blade having an outer end cooperating with the inner end of said skimmer member, for guiding floating scum material into said pocket incident to the rotation of said raking structure, said outer end of the blade having attached thereto a vertical flap of resiliently deflectable material, arranged to provide a sealing relationship with said inner end of the skimmer member, said vertical flap furthermore adapted to be deflected by the respective side of said ramp and of said scum receiving box incident to said skimmer member overriding said ramp and said box.
References Cited (Backward Citations)
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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) | 1980-08-22 | 1981-02-21 | 1981-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-22 | 1985-02-21 | 1985-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-22 | 1989-02-21 | 1989-08-23 | $7700.00 | Window Closed / Lapsed |