Patent US4240578A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4240578A Expired / Lapsed US ⏱️ 0.0 years remaining

Solid bowl decanter centrifuges of the scroll discharge type

Assignee: Individual
•
Filing: 1978-04-26
•
Granted: 1980-12-23
•
Expires: 1998-04-26
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, and adapted to be rotated at a first speed. Inlet pipework enables influent to be introduced to the interior of the bowl. A scroll conveyor is mounted for rotation within the bowl at a second speed. A first motor has its output shaft coupled to the scroll conveyor whereby the motor speed determines the differential speed of the conveyor relative to the bowl. A control mechanism is adapted to measure the torque applied to the scroll conveyor and to control the speed of the scroll conveyor in dependence upon the measured torque, a second pump being adapted to pump flocculant into said inlet pipework at a rate dependent upon the torque controlled differential speed of the scroll conveyor.

Inventors

  • 👤 Joseph F. Jackson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 04:41
CPC Classifications
B; B04; B04B; B04B1/00; B04B1/20; B04B1/2016

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 142 words
In a solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, means for rotating the bowl at a first speed, inlet pipework for introducing influent to the interior of the bowl, a scroll conveyor mounted for rotation within the bowl at a second speed, a first motor whose output shaft is coupled to the scroll conveyer to drive the scroll conveyor at a differential speed relative to the bowl, and a control means for measuring the torque applied to the scroll conveyor and for controlling the speed of the scroll conveyor in dependence upon the measured torque, the improvement comprising a pump means for pumping flocculant into said inlet pipework at a rate dependent upon the differential speed of the scroll conveyor relative to the bowl.
Claim 2
Dependent Claim 142 words
In a solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, means for rotating the bowl at a first speed, inlet pipework for introducing influent to the interior of the bowl, a scroll conveyor mounted for rotation within the bowl at a second speed, a first motor whose output shaft is coupled to the scroll conveyer to drive the scroll conveyor at a differential speed relative to the bowl, and a control means for measuring the torque applied to the scroll conveyor and for controlling the speed of the scroll conveyor in dependence upon the measured torque, the improvement comprising a pump means for pumping flocculant into said inlet pipework at a rate dependent upon the differential speed of the scroll conveyor relative to the bowl.
Claim 3
Dependent Claim 158 words
A solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, means for rotating the bowl at a first speed, inlet pipework for introducing influent to the interior of the bowl, a scroll conveyor mounted for rotation within the bowl at a second speed, a first hydraulic motor whose body is connected to the bowl and whose output shaft is connected to the scroll conveyor to drive the scroll conveyor at a differential speed relative to the bowl, a first pump for supplying hydraulic fluid to said first hydraulic motor, a control means for controlling the pumping rate of said first pump in dependence upon the hydraulic pressure difference across the hydraulic motor, and a second pump means for pumping flocculant into said inlet pipework at a rate dependent upon the torque controlled differential speed of the scroll conveyor relative to the bowl.
Claim 4
Dependent Claim 158 words
A solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, means for rotating the bowl at a first speed, inlet pipework for introducing influent to the interior of the bowl, a scroll conveyor mounted for rotation within the bowl at a second speed, a first hydraulic motor whose body is connected to the bowl and whose output shaft is connected to the scroll conveyor to drive the scroll conveyor at a differential speed relative to the bowl, a first pump for supplying hydraulic fluid to said first hydraulic motor, a control means for controlling the pumping rate of said first pump in dependence upon the hydraulic pressure difference across the hydraulic motor, and a second pump means for pumping flocculant into said inlet pipework at a rate dependent upon the torque controlled differential speed of the scroll conveyor relative to the bowl.
Claim 5
Dependent Claim 79 words
A centrifuge according to claim 2 wherein said first hydraulic motor has a hydraulic fluid supply line, comprising a second hydraulic motor for driving said second pump, said second hydraulic motor being disposed in the hydraulic fluid supply line to the first hydraulic motor driving the scroll conveyor to drive the second hydraulic motor at a speed dependent upon the rate of supply of fluid to the first motor and hence to the rotational speed of the first motor.
Claim 6
Dependent Claim 17 words
A centrifuge according to claim 3 wherein the first pump is of the positive variable displacement type.
Claim 7
Dependent Claim 17 words
A centrifuge according to claim 3 wherein the second pump is of the positive variable displacement type.
Claim 8
Dependent Claim 140 words
A solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, means for rotating the bowl at a first speed, inlet pipework for introducing influent to the interior of the bowl, a scroll conveyor mounted for rotation within the bowl at a second speed, an electric motor whose output shaft is connected to the scroll conveyor to drive the scroll conveyor at a differential speed relative to the bowl, a control means for measuring the torque applied to the scroll conveyor by said motor and for controlling the speed of the motor in dependence upon the measured torque and a pump means for pumping flocculant into said inlet pipework at a rate dependent upon the differential speed of the scroll conveyor relative to the bowl.
Claim 9
Dependent Claim 140 words
A solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, means for rotating the bowl at a first speed, inlet pipework for introducing influent to the interior of the bowl, a scroll conveyor mounted for rotation within the bowl at a second speed, an electric motor whose output shaft is connected to the scroll conveyor to drive the scroll conveyor at a differential speed relative to the bowl, a control means for measuring the torque applied to the scroll conveyor by said motor and for controlling the speed of the motor in dependence upon the measured torque and a pump means for pumping flocculant into said inlet pipework at a rate dependent upon the differential speed of the scroll conveyor relative to the bowl.
Claim 10
Dependent Claim 41 words
A centrifuge according to claim 6 in which the body of the electric motor is coupled to the bowl so as to rotate therewith, and in which the motor shaft is coupled to the scroll conveyor by a mechanical reduction gear.
Claim 11
Dependent Claim 33 words
A centrifuge according to claim 6 in which the motor shaft is coupled to the scroll conveyor via a reduction gear having a housing connected to the bowl so as to rotate therewith.

References Cited (Backward Citations)

US3126337A Cited
US2955753A Cited
FR2070485A5 Cited
US3734399A Cited
SU429850A1 Cited
US4073431A Cited
US4085888A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-12-23 1984-06-23 1984-12-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-12-23 1988-06-23 1988-12-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-12-23 1992-06-23 1992-12-23 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag