Patent US5390545A successfully refreshed from Google Patents.
US5390545A
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Apparatus for measuring torsional vibrations of rotating machinery
Assignee: Caterpillar Inc
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Filing: 1993-01-11
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Granted: 1995-02-21
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Expires: 2013-01-11
Abstract
Abstract An apparatus for measuring torsional vibrations of rotating machinery is provided. A wheel having a plurality of spaced apart teeth is connected to the rotating machinery. A sensor detects the speed of wheel rotation and responsively produces a speed signal that has a frequency proportional to the rotational wheel speed. A timing device receives the speed signal, determines the period of the most recent pulse of the speed signal, and responsively produces an instantaneous period signal that has a value representative of the determined period. A microprocessor receives the instantaneous period signal, determines an instantaneous speed value of the rotating wheel and an average speed value of the rotating wheel based on previous wheel rotations. The microprocessor further produces an instantaneous torsional velocity signal that has a value equal to the difference of the average speed value and the instantaneous speed value, and an instantaneous torsional displacement signal in response to numerically integrating the torsional velocity signal value. Finally, an output device receives the instantaneous torsional signals and displays the representative values.
Inventors
- 👤 Tien D. Doan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:55
CPC Classifications
G; G01; G01H; G01H1/00; G01H1/10
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
190 words
An apparatus for measuring torsional vibrations of rotating machinery, comprising: a wheel having a plurality of spaced apart teeth being connected to and rotating with the rotating machinery; a sensor adapted to detect the speed of rotation of the wheel and responsively produce a speed signal having a frequency proportional to the rotational speed of the wheel, the speed signal having a periodic pulse; timing means for receiving the speed signal, determining the period of the most recent pulse of the speed signal, and responsively producing an instantaneous period signal having a value representative of the determined period; and processing means for receiving the instantaneous period signal, determining an instantaneous speed value of the rotating wheel in response to the value of the instantaneous period signal, determining an average speed value of the rotating wheel based on previous wheel rotations in response to the instantaneous speed value, producing an instantaneous torsional velocity signal having a value equal to the difference of the average speed value and the instantaneous speed value, and producing an instantaneous torsional displacement signal having a value responsive to the integration of the torsional velocity signal value.
Claim 2
Independent Claim
190 words
An apparatus for measuring torsional vibrations of rotating machinery, comprising: a wheel having a plurality of spaced apart teeth being connected to and rotating with the rotating machinery; a sensor adapted to detect the speed of rotation of the wheel and responsively produce a speed signal having a frequency proportional to the rotational speed of the wheel, the speed signal having a periodic pulse; timing means for receiving the speed signal, determining the period of the most recent pulse of the speed signal, and responsively producing an instantaneous period signal having a value representative of the determined period; and processing means for receiving the instantaneous period signal, determining an instantaneous speed value of the rotating wheel in response to the value of the instantaneous period signal, determining an average speed value of the rotating wheel based on previous wheel rotations in response to the instantaneous speed value, producing an instantaneous torsional velocity signal having a value equal to the difference of the average speed value and the instantaneous speed value, and producing an instantaneous torsional displacement signal having a value responsive to the integration of the torsional velocity signal value.
Claim 3
Dependent Claim
44 words
An apparatus, as set forth in claim 1, wherein the processing means includes means for determining the instantaneous speed value, S i , in response to the following equation: S.sub.i =K/T.sub.i where T i represents the instantaneous period value and K represents a constant.
Claim 4
Dependent Claim
38 words
An apparatus, as set forth in claim 2, wherein the processing means including means for determining the average speed value, S ave , in response to the following equation: ##EQU4## and N represents the number of wheel revolutions.
Claim 5
Dependent Claim
27 words
An apparatus, as set forth in claim 3, wherein the processing means includes means for determining the instantaneous torsional velocity value, TV(i), by the following equation: ##EQU5##
Claim 6
Dependent Claim
61 words
An apparatus, as set forth in claim 4, wherein the processing means includes means for determining the instantaneous torsional displacement value, TD(i), in response to the following equation: TD(i)=TD(i-1)+(1/2(TV(i)+TV(i-1) )×T i ×K')-TD ave Where TD(i)=Instantaneous Torsional Displacement TD(i-1)=Previous Torsional Displacement TV(i)=Instantaneous Torsional Velocity TV(i-1)=Previous Torsional Velocity T i =Instantaneous Period K'=Displacement Gain--To convert RPM to Degrees TD ave =Average Torsional Displacement.
Claim 7
Dependent Claim
71 words
An apparatus, as set forth in claim 5, wherein each pulse of the speed signal is defined by rising and falling edges, the timing means includes: means for producing a clock signal having a periodic pulse train; and means for counting the number of pulses of the clock signal that occur between the falling edges of the speed signal, the number of clock signal pulses representing the instantaneous period signal value.
Claim 8
Dependent Claim
24 words
An apparatus, as set forth in claim 6, including a conditioning circuit adapted to receive the speed signal and responsively condition the speed signal.
Claim 9
Dependent Claim
38 words
An apparatus, as set forth in claim 7, including a Digital to Analog signal converting device adapted to receive the instantaneous torsional velocity and displacement signals and convert the instantaneous torsional signals from digital signals to analog signals.
Claim 10
Dependent Claim
17 words
An apparatus, as set forth in claim 8, wherein the processing means includes a digital signal processor.
Claim 11
Dependent Claim
28 words
An apparatus, as set forth in claim 9, including an output device adapted to receive the instantaneous torsional velocity and displacement signals and display the representative values thereof.
Claim 12
Independent Claim
164 words
A method for measuring torsional vibrations of rotating machinery, comprising the steps of: sensing the speed of rotation of the rotating machinery and responsively producing a speed signal having a frequency proportional to the rotational speed of the rotating machinery, the speed signal having a periodic pulse; receiving the speed signal, determining the period of the most recent pulse of the speed signal, and responsively producing an instantaneous period signal having a value representative of the determined period; and receiving the instantaneous period signal, determining an instantaneous speed value of the rotating machinery in response to the value of the instantaneous period signal, determining an average speed value of the rotating machinery based on previous machinery rotations in response to the instantaneous speed value, producing an instantaneous torsional velocity signal having a value equal to the difference of the average speed value and the instantaneous speed value, and producing an instantaneous torsional displacement signal in response to numerically integrating the torsional velocity signal value.
Claim 13
Independent Claim
164 words
A method for measuring torsional vibrations of rotating machinery, comprising the steps of: sensing the speed of rotation of the rotating machinery and responsively producing a speed signal having a frequency proportional to the rotational speed of the rotating machinery, the speed signal having a periodic pulse; receiving the speed signal, determining the period of the most recent pulse of the speed signal, and responsively producing an instantaneous period signal having a value representative of the determined period; and receiving the instantaneous period signal, determining an instantaneous speed value of the rotating machinery in response to the value of the instantaneous period signal, determining an average speed value of the rotating machinery based on previous machinery rotations in response to the instantaneous speed value, producing an instantaneous torsional velocity signal having a value equal to the difference of the average speed value and the instantaneous speed value, and producing an instantaneous torsional displacement signal in response to numerically integrating the torsional velocity signal value.
Claim 14
Dependent Claim
41 words
A method, as set forth in claim 11, including the step of determining the instantaneous speed value, S i , in response to the following equation: S.sub.i =K/T.sub.i where T i represents the instantaneous period value and K represents a constant.
Claim 15
Dependent Claim
35 words
A method, as set forth in claim 12, including the step of determining the average speed value, S ave , in response to the following equation: ##EQU6## and N represents the number of wheel revolutions.
Claim 16
Dependent Claim
26 words
A method, as set forth in claim 13, including the step of determining the instantaneous torsional velocity value, TV(i), in response to the following equation: ##EQU7##
Claim 17
Dependent Claim
54 words
A method, as set forth in claim 14, including the step of determining the instantaneous torsional displacement value, TD(i), in response to the following equation: TD(i)=TD(i-1)+(1/2(TV(i)+TV(i-1))×Ti×K')-TD.sub.ave Where TD(i)=Instantaneous Torsional Displacement TD(i-1)=Previous Torsional Displacement TV(i)=Instantaneous Torsional Velocity TV(i-1)=Previous Torsional Velocity T i =Instantaneous Period K=Displacement Gain-To convert RPM to Degrees TD ave =Average Torsional Displacement.
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) | 1998-02-20 | 1998-08-22 | 1999-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-02-20 | 2002-08-22 | 2003-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-02-20 | 2006-08-22 | 2007-02-21 | $7700.00 | Window Closed / Lapsed |