US4069967A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Centrifuge with chatter suppression
Assignee: Bird Machine Co Inc
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Filing: 1976-10-14
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Granted: 1978-01-24
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Expires: 1996-10-14
Abstract
Abstract Chatter is suppressed in a solids-liquid separating centrifuge by including, in an external connection to a holder of the speed change gearing between the centrifuge bowl and conveyor, a spring and mass means which is torsionally resilient about the axis of the connection such that it will vibrate about that axis under chatter conditions at the chatter frequency, and which has a spring rate within +40% to -25% of the spring rate at which the spring and mass means will vibrate in resonance with the vibration during chatter of the bowl-gearing-conveyor assembly.
Inventors
- 👤 Herbert L. Crosby
- 👤 Jacob P. Den Hartog
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:04
CPC Classifications
B; B04; B04B; B04B9/00; B04B9/14; B04B1/00; B04B1/20; B04B1/2016; B04B2001/2025
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
175 words
In a solids-liquid separating centrifuge of the type which includes an assembly of a rotary bowl member, a rotary conveyor member mounted coaxially therein, and speed change gearing connected between said members so that rotationally driving one of them rotationally drives the other in the same direction at a differential speed, and a torquetransmitting external connection between said gearing and a holder means, the torque on said external connection being relatively low compared to the torque on the connections between said gearing and said bowl and conveyor; the improvement for suppressing chatter of said assembly wherein: said external connection comprises spring and mass means which is torsionally resilient about the axis of said external connection such that it will vibrate about said axis during chatter of said assembly at the same frequency; and the spring of said spring and mass means has a spring rate within the range of +40% to -25% of the spring rate at which said spring and mass means will vibrate in resonance with the vibration of said assembly during chatter.
Claim 2
Dependent Claim
175 words
In a solids-liquid separating centrifuge of the type which includes an assembly of a rotary bowl member, a rotary conveyor member mounted coaxially therein, and speed change gearing connected between said members so that rotationally driving one of them rotationally drives the other in the same direction at a differential speed, and a torquetransmitting external connection between said gearing and a holder means, the torque on said external connection being relatively low compared to the torque on the connections between said gearing and said bowl and conveyor; the improvement for suppressing chatter of said assembly wherein: said external connection comprises spring and mass means which is torsionally resilient about the axis of said external connection such that it will vibrate about said axis during chatter of said assembly at the same frequency; and the spring of said spring and mass means has a spring rate within the range of +40% to -25% of the spring rate at which said spring and mass means will vibrate in resonance with the vibration of said assembly during chatter.
Claim 3
Dependent Claim
13 words
A centrifuge according to claim 1 wherein said holder means is fixedly mounted.
Claim 4
Dependent Claim
13 words
A centrifuge according to claim 1 wherein said holder means is rotatably mounted.
Claim 5
Dependent Claim
20 words
A centrifuge according to claim 1 wherein said spring and mass means comprises a torsion bar coaxial with said connection.
Claim 6
Dependent Claim
15 words
A centrifuge according to claim 4 wherein said torsion bar has substantially no inherent damping.
Claim 7
Dependent Claim
14 words
A centrifuge according to claim 5 wherein said torsion bar is formed of metal.
Claim 8
Dependent Claim
38 words
A centrifuge according to claim 4 wherein said torsion bar includes a portion of reduced diameter and shear strength, said reduced shear strength being low enough to fracture in the event of predetermined torque overload of said assembly.
Claim 9
Dependent Claim
35 words
A centrifuge according to claim 2 wherein said spring and mass means comprises a spring member having its effective spring portion spaced radially outwardly from the axis of the gearing end of said external connection.
Claim 10
Dependent Claim
34 words
A centrifuge according to claim 8 wherein said spring member comprises a leaf spring connected centrally to the gearing end of said external connection and connected adjacent opposite ends thereof to said holder means.
Claim 11
Dependent Claim
17 words
A centrifuge according to claim 1 wherein said external connection comprises a pinion shaft of said gearing.
Claim 12
Dependent Claim
37 words
A centrifuge according to claim 1 wherein the spring of said spring and mass means has a spring rate such that said spring and mass means vibrates in resonance with the vibration of said assembly during chatter.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-23 | 1981-07-25 | 1982-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-23 | 1985-07-25 | 1986-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-23 | 1989-07-25 | 1990-01-24 | $7700.00 | Window Closed / Lapsed |