ROTATING MACHINE ABNORMALITY DIAGNOSIS DEVICE, ROTATING MACHINE ABNORMALITY DIAGNOSIS METHOD, AND ROTATING MACHINE

• US 20170205276A1
• Filed: 08/18/2015
• Published: 07/20/2017
• Est. Priority Date: 09/12/2014
• Status: Active Grant

• Current Assignee: Klaus Schmidt
• Original Assignee: Klaus Schmidt
• Inventors: ASHIDA, Tsuyoshi, TAKAKI, Shugo, ARAKI, Kaname, TAKAHASHI, Eiji, MATSUMOTO, Yasuharu
• Granted Patent: US 10,054,481 B2
• Time in Patent Office: Days
• CPC Class Codes: G01H 17/00 Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups see provisionally also G01H1/00
• CPC Class Codes: G01M 13/00 Testing of machine parts
• CPC Class Codes: G01M 13/028 Acoustic or vibration analysis
• CPC Class Codes: G01M 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A rotating machine abnormality diagnosing apparatus for diagnosing an abnormality in a rotating machine includes: an analyzing part which performs a time-frequency analysis to a signal S representing intensity and time relationship of an elastic wave generating in the rotating machine; an extracting part which extracts second data representing intensity and time relationship of a predetermined frequency component from first data obtained by the time-frequency analysis; and a determining part which determines that a first rotor and a second rotor are in contact with each other when the second data contains intensity variation having a cycle represented by T1×b=T2×a, in which a rotational cycle of the first rotor is denoted by T1, a rotational cycle of the second rotor is denoted by T2, and a ratio of a number of protrusions to a number of recesses is denoted by a:b.

Claims

1. A rotating machine abnormality diagnosing apparatus for diagnosing an abnormality inside a rotating machine which includes a first rotor having a plurality of protrusions, and a second rotor having a plurality of recesses whose number is different from that of the protrusions and arranged against the first rotor at a predetermined gap so that corresponding protrusion and recess among the plurality of protrusions and recesses meet one another sequentially in accordance with rotation of the first rotor and the second rotor, the rotating machine abnormality diagnosing apparatus, comprising:

a sensor which detects an elastic wave generating in the rotating machine, and outputs a signal representing intensity and time relationship of the elastic wave;

an analyzing part which performs a time-frequency analysis to the signal output from the sensor;

an extracting part which extracts second data representing intensity and time relationship of a predetermined frequency component from first data obtained by the time-frequency analysis of the analyzing part; and

a determining part which determines that the first rotor and the second rotor are in contact with each other when the second data contains intensity variation having a cycle represented by T1×

b=T2×

a, in which a rotational cycle of the first rotor is denoted by T1, a rotational cycle of the second rotor is denoted by T2, and a ratio of the number of the protrusions and the number of the recesses is denoted by a;

b.

2. A rotating machine abnormality diagnosing apparatus according to claim 1, wherein

the rotating machine further includes a casing for accommodating the first rotor and the second rotor, and

the determining part determines that the first rotor and the casing are in contact with each other when the second data contains intensity variation having a cycle represented by T1, and determines that the second rotor and the casing are in contact with each other when the second data contains intensity variation having a cycle represented by T2.

3. A rotating machine abnormality diagnosing apparatus according to claim 2, wherein

the determining part determines whether or not the first rotor and the second rotor are in contact with each other, after determining whether or not the first rotor and the casing are in contact with each other, and whether or not the second rotor and the casing are in contact with each other.

5. A rotating machine including the rotating machine abnormality diagnosing apparatus according to claim 1.

4. A rotating machine abnormality diagnosing method for diagnosing an abnormality inside a rotating machine which includes a first rotor having a plurality of protrusions, and a second rotor having a plurality of recesses whose number is different from that of the protrusions and arranged against the first rotor at a predetermined gap so that corresponding protrusion and recess among the plurality of protrusions and recesses meet one another sequentially in accordance with rotation of the first rotor and the second rotor, the rotating machine abnormality diagnosing method, comprising:

a detecting step of detecting an elastic wave generating in the rotating machine, and outputting a signal representing intensity and time relationship of the elastic wave;

an analyzing step of performing a time-frequency analysis to the signal output in the detecting step;

an extracting step of extracting second data representing intensity and time relationship of a predetermined frequency component from first data obtained by the time-frequency analysis in the analyzing step; and

a determining step of determining that the first rotor and the second rotor are in contact with each other when the second data contains intensity variation having a cycle represented by T1×

b=T2×

a, in which a rotational cycle of the first rotor is denoted by T1, a rotational cycle of the second rotor is denoted by T2, and a ratio of the number of the protrusions and the recesses is denoted by a;

b.