JPH09113491A - Ae diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a diagnostic apparatus which is provided with a judgment function by the sense of sight and by the sense of hearing by a method wherein a display function which displays the output level of an AE sensor and a hearing function which can hear the output signal of the AE sensor by a human ear are housed inside the same case. SOLUTION: The output of an AE sensor 1 is amplified by a preamplifier 2 and a main amplifier 3, an AE signal is converted into a direct current by a mean-value circuit 4, a converted signal is input to a level monitor 5. The level monitor 5 is constituted of an analog indicator or of a digital bar graph display. The output of the main amplifier 3 is input to a frequency conversion circuit 6 which is constituted of a detection circuit 6a and of an audio signal amplifier circuit 6b. The detection circuit 6a detects an AE signal, and it lowers the AE signal down to a frequency band of 20kHz which can be heard by a human ear. A detection signal which is amplified by the audio signal amplifier circuit 6b is output to a headphone 7. In this manner, since information on the AE signal can be known simultaneously by the level meter and the headphone, the state of a machine can be judged by an audiovisual function with which a human being is endowed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an AE measuring apparatus applied to machine abnormality diagnosis and the like, and more particularly to a portable AE measuring apparatus developed so as to be easily used for patrol inspection of a field machine. .

[0002]

2. Description of the Related Art In many AE diagnostic devices used for machine condition monitoring and diagnosis, a preamplifier and a main amplifier are separated, and further, the output signals of the main amplifier and the main amplifier are processed to check the machine condition. The diagnostic function (PC etc.) for judging was also separated. In addition to this, there is no AE measuring device in which a level meter capable of seeing the fluctuation of the AE output in real time and an audible sound monitor capable of hearing the output signal of the AE in a human ear are housed in the same case.

A typical known example of a machine diagnostic device based on AE will be described below.

[0004]

For example, when diagnosing a machine of a power plant using AE measurement technology,
AE sensor, preamplifier, method of installing and using diagnostic function and equipment are carried and diagnosed every time of inspection (patrol inspection)
Two types of methods are possible. In the former case, the size of the device does not matter. The publicly known examples described above correspond to these examples. In the latter case, the size of the device has never been smaller and lighter. Therefore, the former example is not suitable for the usage described in the latter.

An AE device in which a preamplifier and a main amplifier, an output level display function of the main amplifier, and a function of allowing an operator to hear the output signal of the main amplifier by an ear are integrated and housed in a case. If so, patrol inspection becomes easier. Further, if the above-mentioned case has a diagnostic function and a memory function for storing a diagnostic result, it is further effective for machine diagnosis.

[0006]

As a first device for solving the above problems, a display function for displaying an output level of an AE sensor and a hearing function capable of listening to an output signal of the AE sensor by a human ear. An AE diagnostic device is constructed by storing and in the same case.

As a second device for solving the above problems, a preamplifier for amplifying the output of the AE sensor, a main amplifier and a level monitor capable of externally displaying the output level of the main amplifier, and the frequency of the output signal of the main amplifier are displayed. An AE characterized in that a frequency conversion circuit for lowering to the audible band is housed in the same case, and an audible sound monitor is provided for listening to the output of the frequency conversion circuit with human ears.
Configured the diagnostic device. As a third device for solving the above problems, a preamplifier for amplifying the output of the AE sensor,
A level monitor that can display the output level of the main amplifier and the main amplifier externally, a frequency conversion circuit that lowers the frequency of the output signal of the main amplifier to the audible band, and the output signal of the main amplifier are analyzed to determine the state of the machine. The AE diagnostic device is characterized by accommodating the diagnostic function described above in the same case and further including an audible sound monitor for listening to the output of the frequency conversion circuit by the human ear.

As a fourth device for solving the above problems, a preamplifier for amplifying the output of the AE sensor, a main amplifier, a level monitor capable of externally displaying the output level of the main amplifier, and a frequency of the output signal of the main amplifier. The frequency conversion circuit that lowers the output to the audible band and the diagnostic function that analyzes the output signal of the main amplifier to determine the state of the machine and the memory function that records the output signal of the main amplifier and the analysis result of the diagnostic function are the same case. Stored inside,
Further, an AE diagnostic device is provided which is equipped with an audible sound monitor for listening to the output of the frequency conversion circuit by the human ear.

A preamplifier for amplifying the output of the AE sensor,
The main amplifier and the level monitor that can display the output level of the main amplifier to the outside and the frequency conversion circuit that lowers the frequency of the output signal of the main amplifier to the audible band are housed in the same case. Equipped with an audible sound monitor for listening by ear. By integrating all the above-mentioned functions, the device is downsized, and it becomes easy to carry during patrol inspection. Further, since the AE signal information can be known at the same time by the visual sense (level monitor) and the auditory sense (headphones), the state of the machine can be determined by both functions of human being, and the AE information is less likely to be overlooked.

In addition to the above-mentioned functions, a diagnostic function for judging the state of the machine and a memory function for recording the output signal of the main amplifier and the analysis result of the diagnostic function are housed in the same case.
Therefore, detailed diagnosis can be performed on site. Further, if the data recorded in the memory function is brought back to the office and connected to a personal computer or a large computer, it becomes possible to manage the machine tendency.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an AE diagnostic apparatus of the present invention. After the output of the AE sensor 1 is amplified by the preamplifier 2 and the main amplifier 3, the average value circuit 4 converts the AE signal into direct current. The signal converted into direct current is input to the level monitor 5. The level monitor 5 is composed of an analog type indicator or a digital type bar graph display.
In the above-described embodiments, the example in which the average value circuit is used as the signal processing circuit for inputting to the level monitor has been described. Any circuit that can convert the output level of the AE signal into a signal that can be displayed by a level monitor, such as an effective value or a peak hold circuit, may be used.

On the other hand, the output of the main amplifier 3 is input to the frequency conversion circuit 6. The frequency conversion circuit 6 is the detection circuit 6
a and an audio signal amplifier circuit 6b. Usually AE
Since the signal is measured in the frequency band of 50 kHz to 2 MHz, it is difficult to amplify the AE signal itself and listen to it through a speaker or the like. Therefore, in the present invention, as described above, the AE signal is detected, and the AE signal is lowered to the frequency band (20 kHz or less) audible to the human ear. The detection signal amplified by the audio signal amplifier circuit 6b is output to the headphone 7 provided outside. Except for the AE sensor 1 and the headphones 7, all are housed in one case 8. Change to headphones 7 as shown in FIG.
An AE diagnostic device in which the speaker 9 is housed in the case 8 can also achieve substantially the same effect as the example shown in FIG. AE in FIG.
An external appearance example of a diagnostic device is shown. Each function is stored in the same case, making it easy to carry.

An effective parameter in machine diagnosis is the AE level. In our experience, approximately 50% of machine diagnoses are possible at the AE level. Therefore, the AE diagnostic apparatus of the present invention is effective in the patrol inspection of machines on site. Furthermore, a voice monitor for AE signals is also provided. Since the AE signal information can be known at the same time with the visual sense (level meter) and the auditory sense (headphones), the state of the machine can be determined by both functions of human beings. Even if the operator overlooks the level meter during work, since he or she listens to the voice monitor, it is less likely that the AE information useful for diagnosis will be overlooked.

The embodiment of FIG. 4 is an extension of the embodiment of FIG.
The output of the main amplifier 3 is input to the microcomputer 10. A start switch 11 and a reset switch 13 are connected to the microcomputer 10. When the command from the start switch 11 is input to the microcomputer 10, the microcomputer 10 takes in a signal from the main amplifier 3 and diagnoses the target machine based on a predetermined algorithm. Next, the diagnosis result is output to the display unit 12. When the diagnosis is to be performed again, the reset switch 13 and the start switch 11 are pressed to enable the diagnosis. The microcomputer 10 is, for example,
It can be configured with a one-chip microcomputer H8 sold by Hitachi, Ltd.

If a data memory function is added to the above-mentioned function, data will not be overlooked. Specifically, as shown in FIG. 4, the memory 14 is connected to the microcomputer 10,
The parameter values calculated by the microcomputer 10 and the diagnostic result are stored. The memory 14 may be a RAM or a storage medium such as an IC card. Further, the microcomputer 10 is provided with a communication medium with a personal computer such as RS232C. Data is discharged to the personal computer by the connector 15. This is when you return to the office from the scene,
This is an item to be implemented. This is to make up for the insufficient storage capacity of the memory 14 described above. By inputting data for each tour to the personal computer, it becomes possible to manage the machine tendency. FIG. 5 shows an example of the external appearance of the AE diagnostic device described above. The display unit 12 can be configured by an LED or the like. A liquid crystal display can be used when a text message or graphic display is required.

[0016]

The functions capable of simultaneously outputting the visual function (level monitor) and the auditory function (headphones), which are important sensibilities among the human five senses, are summarized in a compact and lightweight case. By using this device, the AE signal information can be known at the same time, and therefore the state of the machine can be determined by both functions of human beings. Even if the operator overlooks the level meter during work, since he or she listens to the voice monitor, it is less likely that the AE information useful for diagnosis will be overlooked. In addition, the diagnostic device also has a judgment function (microcomputer) that can be equipped with a machine diagnostic algorithm and a storage medium that can record data. It is a portable AE diagnostic device equipped with a machine diagnostic function.

[Brief description of the drawings]

FIG. 1 is a block diagram of a first proposal of an AE diagnostic device.

FIG. 2 is a block diagram of a second proposal of the AE diagnostic device.

FIG. 3 is a perspective view of a first proposal of the AE diagnostic device.

FIG. 4 is a block diagram of a third proposal of the AE diagnostic device.

FIG. 5 is a perspective view of a third proposal of the AE diagnostic device.

[Explanation of symbols] 1 ... AE sensor, 2 ... preamplifier, 3 ... main amplifier,
4 ... Average value circuit, 5 ... Level monitor, 6 ... Frequency conversion circuit, 7 ... Headphone, 8 ... Case.

Claims (4)

[Claims] 1. An AE diagnostic apparatus, wherein a display function for displaying an output level of an AE sensor and an auditory function capable of hearing an output signal of the AE sensor with a human ear are housed in the same case. 2. A preamplifier for amplifying the output of the AE sensor,
The main amplifier, a level monitor capable of displaying the output level of the main amplifier to the outside, and a frequency conversion circuit for lowering the frequency of the output signal of the main amplifier to the audible band are housed in the same case, and the output of the frequency conversion circuit is An AE diagnostic device comprising an audible sound monitor for hearing with human ears. 3. A preamplifier for amplifying the output of the AE sensor,
A level monitor that can display the output level of the main amplifier and the main amplifier to the outside, a frequency conversion circuit that lowers the frequency of the output signal of the main amplifier to the audible band, and the output signal of the main amplifier are analyzed to determine the state of the machine. An AE diagnostic apparatus, characterized in that the diagnostic function described above is housed in the same case, and that an audible sound monitor for listening to the output of the frequency conversion circuit by the human ear is further provided. 4. A preamplifier for amplifying the output of the AE sensor,
A level monitor that can display the output level of the main amplifier and the main amplifier to the outside, a frequency conversion circuit that lowers the frequency of the output signal of the main amplifier to the audible band, and the output signal of the main amplifier are analyzed to determine the state of the machine. A diagnostic function for storing and a memory function for recording the output signal of the main amplifier and the analysis result of the diagnostic function are housed in the same case, and an audible sound monitor for listening to the output of the frequency conversion circuit by the human ear is provided. An AE diagnostic device characterized in that