Centrifugal separator apparatus having a vibration sensor

• US 5,879,279 A
• Filed: 09/05/1996
• Issued: 03/09/1999
• Est. Priority Date: 09/05/1996
• Status: Expired due to Term

• Current Assignee: U.S. Centrifuge
• Original Assignee: U.S. Centrifuge
• Inventors: Behrens, Scott, Berger, Jeffrey L.
• Primary Examiner(s): Cooley, Charles E.
• Application Number:
  US08/707,621
• Time in Patent Office: 915 Days
• Field of Search: 494/1, 494/55, 494/7-9, 494/10, 494/11, 494/50-52, 494/82, 494/84, 210/144, 210/363, 68/12.06
• US Class Current: 494/7
• CPC Class Codes: B04B 11/043 Load indication with or without control arrangements
• CPC Class Codes: B04B 11/08 Skimmers or scrapers for discharging ; Regulating thereof
• CPC Class Codes: B04B 9/146 Unbalance detection devices

Abstract

A centrifugal separator apparatus for separating a composition to a substantially solid portion and a substantially liquid portion. A dual mode vibration sensor is located radially outward from a shaft utilized for rotating a bowl. The vibration sensor for sensing the radial vibration of the bowl during rotation. Upon the vibration sensor sensing radial vibration above a first predetermined threshold or a second predetermined threshold, a signal is sent to a controller that activates a D.C. brake or frequency inverter to stop the rotation of the bowl. Further, in another embodiment, the centrifugal separator includes a directing member within the bowl for directing the composition outwardly toward the wall of the bowl during rotation to increase the separation of the liquid and the solids.

Claims

1. A centrifugal separator, comprising:

a bowl for receiving a composition of liquid and solids therein;

a first motor coupled to said bowl for rotating said bowl to substantially separate the liquid and solids during a separation mode;

a plow blade rotatable within said bowl for dislodging solids accumulated within said bowl, said plow blade being rotatable relative to said bowl not during said separation mode;

a vibration sensor associated with said bowl for sensing radial vibration of said bowl while said bowl is rotated by said motor, and wherein said vibration sensor having a first predetermined threshold and a second predetermined threshold, and wherein said vibration sensor upon sensing radial vibration above either said first predetermined threshold or said second predetermined threshold sends at least one signal;

a controller in communication with said vibration sensor, said controller receiving said at least one signal from said vibration sensor to control said bowl rotation during said separation mode; and

a stop device in communication with said controller, said controller activating said stop device to stop the rotation of said bowl upon receiving said at least one signal, said controller activating the rotation of said plow blade during a cleaning mode to clean said bowl.

2. The separator of claim 1, wherein said first predetermined threshold has a first magnitude component and said second predetermined threshold has a second magnitude component, and wherein said first magnitude component is greater than said second magnitude component.

3. The separator of claim 2, wherein said first predetermined threshold has a first time duration component and said second predetermined threshold has a second time duration component, and wherein said first time duration component is less than said second time duration component.

4. The separator of claim 3, wherein said first time duration component is in the range of about 2-15 seconds and said second time duration component is about sixty seconds.

5. The separator of claim 3, which further includes a bypass period wherein said second predetermined threshold is bypassed for an initial period following the commencement of processing of the composition of liquid and solids.

6. The separator of claim 5, wherein said bypass period is about five minutes.

7. The separator of claim 2, wherein said first magnitude component is less than about 1.5 inches/second and said second magnitude component is less than about 0.75 inches/second.

8. The separator of claim 7, wherein said first magnitude component is about 0.5 inches/second, and said second magnitude component is about 0.25 inches/second.

9. The separator of claim 1, wherein said plow blade rotates at a speed substantially less than the speed of said bowl during said cleaning mode.

10. The separator of claim 9, wherein the duration of rotation of said bowl being limited by a timer.

11. The separator of claim 1, wherein said stop device is a brake.

12. The separator of claim 1, wherein said stop device is a frequency inverter.

13. A centrifugal separator, comprising:

a bowl for receiving a composition of liquid and solids therein, said bowl having a liquid discharge, a particle discharge and an outer wall member extending therebetween;

a first motor coupled to said bowl for rotating said bowl to substantially separate the liquid and solids during a separation mode;

a directing member positioned within said bowl proximate said liquid discharge for directing said composition outwardly toward said wall member during rotation so as to increase the separation of the liquid and solids, said directing member remains stationary with respect to said bowl during the separation of the liquid and solids;

a plow blade rotatable within said bowl for dislodging solids accumulated within said bowl, said plow blade being rotatable relative to said bowl not during said separation mode;

a vibration sensor associated with said bowl for sensing radial vibration of said bowl while said bowl is rotated by said motor, and upon said vibration sensor sensing radial vibration above a first predetermined threshold said bowl rotation being stopped.

14. The separator of claim 13, wherein said directing member is a substantially annular ring, and wherein said bowl is symmetrical about a vertical centerline.

15. The separator of claim 13, wherein said vibration sensor is a dual output sensor.

16. The separator of claim 15, wherein said vibration sensor has a first predetermined threshold and a second predetermined threshold, said first predetermined threshold has a first magnitude component and said second predetermined threshold has a second magnitude component, and wherein said first magnitude component is greater than said second magnitude component, wherein said first predetermined threshold has a first time duration component and said second predetermined threshold has a second time duration component, and wherein said first time duration component is less than said second time duration component.

17. A centrifugal separator, comprising:

a motor;

a shaft coupled to said motor;

a frame including a member, said member having a portion of said shaft rotatable coupled thereto;

a bowl for receiving a composition of liquid and solids therein, said bowl coupled to said shaft and rotatable therewith to substantially separate the liquid and solids during a separation mode; and

a dual output vibration sensor coupled to said frame and spaced radially outward from said shaft for sensing radial vibration of said bowl while said bowl is rotated.

18. The separator of claim 17, which further includes a controller, and wherein said vibration sensor having a first predetermined threshold and upon sensing radial vibration of said bowl above said first predetermined threshold a first signal is sent to said controller to stop the rotation of said bowl, and a second predetermined threshold and upon sensing radial vibration of said bowl above said second predetermined threshold a second signal is sent to said controller to stop the rotation of said bowl.

19. The separator of claim 18, wherein said first predetermined threshold is designed to trigger a signal in response to an emergency or a dynamic imbalance condition, and wherein said second predetermined threshold is designed to trigger a signal in response to a full bowl condition.

20. The separator of claim 17, wherein said bowl includes a wall member, and which further includes a directing member positioned within said bowl for directing the composition outwardly toward said wall member during rotation so as to increase the separation of the liquid and solids, and further including a scraper blade rotatable within said bowl for dislodging solids accumulated within said bowl.

21. The separator of claim 20, wherein said directing member remains stationary with respect to said bowl during the separation of the liquid and solids, and said vibration sensor is spaced radially outward from said wall member.

22. The separator of claim 21, wherein:

said bowl is symmetrical about a vertical centerline, and wherein said bowl is rotatable about said centerline; and

wherein said vibration sensor includes a first predetermined threshold and a second predetermined threshold, and wherein said first predetermined threshold has a first magnitude component and said second predetermined threshold has a second magnitude component, and wherein said first magnitude component is greater than said second magnitude component, wherein said first predetermined threshold has a first time duration component and said second predetermined threshold has a second time duration component, and wherein said first time duration component is less than said second time duration component.

23. The separator of claim 22, wherein said first magnitude component is less than about 1.5 inches/second and said second magnitude component is less than about 0.75 inches/second, and wherein said first time duration component is in the range of about 2-15 seconds and said second time duration component is about sixty seconds.

24. A centrifugal separator, comprising:

a frame including a member;

a bowl for receiving a composition of liquid and solids therein, said bowl rotatably coupled with said member;

a motor coupled to said bowl for rotating said bowl relative to said frame so as to substantially separate the liquid and solids during a separation mode;

a plow blade assembly disposed within and rotatable relative to said bowl for dislodging material accumulated within said bowl, said plow blade being rotatable relative to said bowl not during said separation mode;

a vibration sensor coupled to said frame for sensing radial vibration of said bowl during said separation mode, and said vibration sensor is spaced radially from said bowl, said vibration sensor having a first predetermined threshold and a second predetermined threshold, and upon said vibration sensor sensing radial vibration above one of said first predetermined threshold and said second predetermined threshold said bowl rotation is stopped.

25. The separator of claim 24:

which further includes a controller for receiving at least a signal from said vibration sensor for controlling said bowl rotation during said separator mode; and

wherein said controller activating a stop device to stop the rotation of said bowl upon receiving a signal associated with either said first predetermined threshold or said second predetermined threshold.

26. The separator of claim 25, wherein said stop device is one of a brake and a frequency inverter.

27. The separator of claim 24, wherein said vibration sensor is PCM/BETA model 440D vibration switch.