CN212007510U - Noise detection system - Google Patents
Noise detection system Download PDFInfo
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- CN212007510U CN212007510U CN201922383589.9U CN201922383589U CN212007510U CN 212007510 U CN212007510 U CN 212007510U CN 201922383589 U CN201922383589 U CN 201922383589U CN 212007510 U CN212007510 U CN 212007510U
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Abstract
The embodiment of the invention discloses a noise detection system, which comprises a microphone capable of being pasted on detected equipment, terminal equipment provided with various intelligent processing and analysis algorithms, the detected equipment and a data line for connecting the microphone and the terminal; the microphone is adhered to the surface of the detected equipment, the terminal equipment receives noise data collected by the microphone through a data line, and the noise data are processed by adopting a pre-installed intelligent processing and analyzing algorithm. The movable glue is arranged on the microphone main body, so that the microphone can be directly pasted on the industrial equipment, the problem of inaccurate noise detection caused by a certain distance between the noise acquisition equipment and a sound source is reduced, a fixing support or a fixing hole is not required to be installed on the industrial equipment, and the damage to the equipment is reduced. The microphone adhered to the surface of the industrial equipment is small, exquisite and convenient to use.
Description
Technical Field
The embodiment of the invention relates to the technical field of noise acquisition, in particular to a noise detection system.
Background
Vibration and noise are inherent signals generated when mechanical equipment runs, and like vibration, the noise signals can reflect running state information of the equipment. By analyzing the sound pressure level, waveform characteristics, and frequency components of the noise, the presence or absence of an obstacle of the device can be detected, and the type of the failure can be determined. Compared with vibration detection, the noise detection has the advantages of low cost, easy acquisition of signals, convenience for on-line detection and the like. Under the environment that the vibration sensor is difficult to install or the vibration sensor is difficult to work normally such as high temperature, high corruption, noise detection plays an important role.
The microphone is an electroacoustic device which converts sound signals into electric signals, and the energy conversion process is as follows: firstly, the sound wave receiver receives the sound wave and converts the sound wave into corresponding mechanical vibration, and then the mechanical vibration generates a corresponding electric signal. The sound pressure generated by a sound source at a point is inversely proportional to the distance from the point to the sound source, and thus the closer to the sound source, the greater the change in sound pressure. When the sound source is close to the microphone to make sound, the low frequency of the sound is greatly improved, namely, the near field effect is generated. Generally, near field effects begin to appear when the microphone is about one meter away from the sound source, and the closer the microphone is, the more obvious the distance is.
When some mechanical equipment with low rotating speed or low-frequency impact is used for noise diagnosis, the low-frequency part in the noise is particularly important, and the part of sound can reflect the characteristics of the equipment such as rotating speed, running stability, impact frequency and the like. The traditional noise acquisition equipment is usually kept at a certain distance from a sound source due to the limitation of volume and a fixing mode, and the low-frequency part in the recorded sound is covered by high frequency and environmental noise to a certain extent, so that the diagnosis capability of the traditional noise acquisition equipment on mechanical equipment with low rotating speed and low frequency impact in the actual use process is limited. The existing noise acquisition equipment is mostly fixed by using a special support, certain requirements are also provided for a test field, welding or punching on the equipment are needed for installation when the equipment is used on some obvious equipment, the existing noise acquisition equipment is often used in combination with a signal amplifier and a filter, the equipment needs additional power supply, besides the special noise acquisition equipment, the handheld noise detector is widely applied, but the equipment can only detect the sound pressure level of sound, and the component characteristics of the sound cannot be further analyzed, so that the application in the field of fault diagnosis of mechanical equipment is limited.
Most of the existing industrial noise collecting devices do not consider convenience, need to use a special support for fixing, require a test area to have a place for installing the device, and are difficult to use in some complex field environments or narrow spaces. Many mechanical equipment are bulky, and the during operation vibration is obvious, and noise acquisition equipment will keep away from the sound source if placing too far away, and easily receive environmental noise interference, can not accurately record the noise characteristic. This greatly increases the difficulty of fault diagnosis, resulting in erroneous judgment of the state of the operating device. If the sound source is close to, a mounting bracket welded or punched on the surface of the mechanical equipment is needed to fix the noise collecting equipment, which obviously causes certain damage to the equipment, and is particularly difficult to bear for some high-cost or precise mechanical equipment. Although the traditional handheld noise detector is convenient to use, as long as the sound pressure level of the sound is detected, the characteristics of the sound such as waveform, frequency and fundamental tone cannot be further analyzed, and the operating state and the fault type of the equipment cannot be judged accordingly. High-grade noise analysis capable of analyzing sound characteristics is produced by foreign companies, and the price and the cost are higher.
Disclosure of Invention
Therefore, the embodiment of the invention provides a noise detection system, which aims to solve the problems that in the prior art, the existing noise acquisition and diagnosis equipment is far away from a sound source, has a large volume, and needs to weld or punch a mounting bracket on the surface of mechanical equipment during installation, so that the fault diagnosis is difficult and the installation is inconvenient.
In order to achieve the above object, an embodiment of the present invention provides a noise detection system, where the microphone is small in size, can be attached to a device to be detected to collect a sound signal, and is connected to a terminal device through a data connector to analyze and judge the collected sound signal, so as to implement one-stop processing of mechanical device noise collection and analysis processing, and can greatly reduce noise collection and analysis costs, so that the application prospect of the noise test technology is wider. The specific technical scheme is as follows:
according to a first aspect of embodiment 1 of the present invention, there is provided a noise detection system, including a microphone capable of being attached to a device under test, a terminal device equipped with a plurality of intelligent processing and analysis algorithms, the device under test, and a data line connecting the microphone and the terminal; the microphone is adhered to the surface of the detected equipment, the terminal equipment receives noise data collected by the microphone through a data line, and the noise information is processed by adopting a pre-installed intelligent processing and analyzing algorithm.
Further, the microphone comprises a microphone body (1), a sound transmission hole (2) fixed on the microphone body (1), a data connector (3) fixed on the top surface of the microphone body (1), a vibration damping rubber (4) arranged on the microphone body (1) and a removable rubber (5) arranged on the surface of the vibration damping rubber (4); a microphone (6) and a signal processing circuit board (7) are arranged in the microphone main body (1); the movable rubber (5) is used for being pasted on equipment to be detected, the vibration reduction rubber (4) is used for reducing the influence of vibration of mechanical equipment on sound collection, sound collected through the sound transmission holes (2) is transmitted into the signal processing circuit board (7) to be subjected to data processing and analysis, and the processed signals are output through the data connector (3).
Further, the microphone body (1) is cubic or cylindrical;
when the microphone main body (1) is a cube, the sound transmission hole (2), the removable rubber (5) and the vibration reduction rubber (4) are all arranged on the same side face of the microphone main body (1), the sound transmission hole (2) is arranged at the lower part of the microphone main body (1), the vibration reduction rubber (4) is arranged at the upper part of the sound transmission hole (2), and the removable rubber (5) is arranged on the surface of the vibration reduction rubber (4);
when the microphone main body (1) is a cylinder, the sound transmission hole (2) and the vibration reduction rubber (4) are arranged on the bottom surface of the microphone main body (1); the vibration reduction rubber (4) and the movable rubber (5) are both circular rings, and the sound transmission hole (2) is formed in the center of each circular ring.
Furthermore, the signal processing circuit board (7) comprises an interface circuit, a signal preprocessing circuit, an analog-to-digital conversion circuit and a data transmission circuit which are connected in sequence; the interface circuit is electrically connected with the microphone (6).
Furthermore, the signal preprocessing circuit comprises a filtering processing circuit and a pre-amplifying processing circuit; the analog-to-digital conversion circuit comprises a sampling circuit and a quantization and coding circuit; the data transmission circuit comprises a wired data transmission circuit and a wireless data transmission circuit.
Further, the wireless data transmission circuit comprises at least one of the following modes: 3G, 4G, 5G, WiFi, ZigBee.
Further, the terminal device comprises one of a smart phone, a pad, a PC and a handheld device.
Further, the system also comprises a cloud server, wherein the cloud server is connected with the terminal equipment; the terminal equipment sends the received noise information to a cloud server for processing and storing;
or uploading a processing result obtained after the noise information is processed by the terminal equipment to a cloud server for storage.
The embodiment of the invention has the following advantages:
according to the microphone adhered to the surface of the industrial equipment, provided by the embodiment 1 of the invention, the movable adhesive is arranged on the microphone main body, so that the microphone can be directly adhered to the industrial equipment needing noise detection, the problem of inaccurate noise detection caused by a certain distance between the noise collection equipment and a sound source is reduced, meanwhile, a fixing support or a fixing hole is not required to be specially installed on the detected industrial equipment, and the damage to the equipment is reduced. In addition, the removable adhesive can be adhered and removed at any time, and the microphone adhered to the surface of the industrial equipment is small, exquisite and convenient to use.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.
The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so that those skilled in the art can understand and read the present invention, and do not limit the conditions for implementing the present invention, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the functions and purposes of the present invention, should still fall within the scope of the present invention.
Fig. 1 is a schematic structural diagram of a noise detection system according to embodiment 1 of the present invention;
fig. 2a to 2b are a front view and a side view of a preferred structure of a microphone attached to a surface of an industrial device according to embodiment 1 of the present invention;
fig. 2c to 2d are a front view and a side view of another preferred structure of a microphone adhered to a surface of an industrial device according to embodiment 1 of the present invention;
fig. 3 is a schematic block diagram of a signal processing circuit board (7) of a microphone attached to a surface of an industrial device according to embodiment 1 of the present invention;
in the figure: 1: a microphone main body; 2: a sound transmission hole; 3: a data connector; 4: damping rubber; 5: glue moving; 6: a microphone; 7: and a signal processing circuit board.
Detailed Description
The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, a schematic structural diagram of a noise detection system provided in embodiment 1 of the present invention includes a microphone capable of being pasted on a device to be detected, a terminal device installed with multiple intelligent processing and analysis algorithms, the device to be detected, and a data line connecting the microphone and the terminal; the microphone is adhered to the surface of the detected equipment, the terminal equipment receives noise data collected by the microphone through a data line, and the noise information is processed by adopting a pre-installed intelligent processing and analyzing algorithm.
Further, a microphone of a noise detection system provided in embodiment 1 of the present invention includes a microphone main body (1), a sound transmission hole (2) fixed to the microphone main body (1), a data connector (3) fixed to a top surface of the microphone main body (1), a vibration damping rubber (4) disposed on the microphone main body (1), and a removable rubber (5) disposed on a surface of the vibration damping rubber (4); a microphone (6) and a signal processing circuit board (7) are arranged in the microphone main body (1); the movable rubber (5) is used for being pasted on equipment to be detected, the vibration reduction rubber (4) is used for reducing the influence of vibration of mechanical equipment on sound collection, sound collected through the sound transmission holes (2) is transmitted into the signal processing circuit board (7) to be subjected to data processing and analysis, and the processed signals are output through the data connector (3).
The microphone main body (1) is a cube or a cylinder; referring to fig. 2a to 2d, fig. 2a to 2b are a front view and a side view of a preferred structure of a microphone adhered to a surface of an industrial device according to embodiment 1 of the present invention, when the microphone body (1) is a cube, the sound transmission hole (2), the removable rubber (5), and the vibration reduction rubber (4) are all disposed on the same side of the microphone body (1), the sound transmission hole (2) is disposed on a lower portion of the microphone body (1), the vibration reduction rubber (4) is disposed on an upper portion of the sound transmission hole (2), and the removable rubber (5) is disposed on a surface of the vibration reduction rubber (4).
Referring to fig. 2c to 2d, which are a front view and a side view of another preferred structure of a microphone adhered to a surface of an industrial device according to embodiment 1 of the present invention, when the microphone body (1) is a cylinder, the sound transmission hole (2) and the vibration reduction rubber (4) are both disposed on the bottom surface of the microphone body (1); the vibration reduction rubber (4) and the movable rubber (5) are both circular rings, and the sound transmission hole (2) is formed in the center of each circular ring.
Fig. 3 is a schematic block diagram of a signal processing circuit board (7) of a microphone attached to a surface of an industrial device according to embodiment 1 of the present invention; the signal processing circuit board (7) comprises an interface circuit, a signal preprocessing circuit, an analog-to-digital conversion circuit and a data transmission circuit which are connected in sequence; the interface circuit is electrically connected with the microphone (6). The signal preprocessing circuit comprises a filtering processing circuit and a pre-amplifying processing circuit; the analog-to-digital conversion circuit comprises a sampling circuit and a quantization and coding circuit; the data transmission circuit comprises a wired data transmission circuit and a wireless data transmission circuit. The wireless data transmission circuit comprises at least one of the following modes: 3G, 4G, 5G, WiFi, ZigBee.
In the practical application scenario of embodiment 1 of the present invention, the microphone of the present invention mainly comprises a microphone, an internal circuit, a data connector, a housing, a vibration damping rubber, and a removable rubber. The shape of the microphone can be designed into a square shape, and a data connector is led out from the side surface of the microphone; the microphone can also be designed into a round shape, and a data connector is led out from the back of the microphone. When sound data are collected, the data line and the mobile phone need to be matched for use, one end of the data line is connected to the microphone, the other end of the data line is connected to the mobile phone, and then sound recording can be carried out.
The microphone converts received sound signals into electric signals, partial environmental noise and signals with overhigh frequency are removed through a signal preprocessing module in an internal circuit, then the electric signals enter an analog-digital conversion module and are converted into digital signals, and finally the digital signals are transmitted to a mobile phone through a data line to be stored and analyzed. Because the microphone of this patent mainly uses the scene for detecting low rotational speed and have the noise of low frequency impact equipment, so be provided with low pass filter circuit at signal preprocessing module to get rid of the high frequency signal in the certain limit, make the audio data of record more accord with the diagnosis demand.
When the microphone is close to the sound source, the low-frequency part in the recorded equipment noise is greatly improved due to the influence of the near-field effect. Generally, near field effects begin to appear when the microphone is about one meter away from the sound source, and the closer the microphone is, the more obvious the near distance is. The sound characteristic of mechanical equipment with low rotating speed can be well recorded by utilizing the phenomenon. When the equipment fails in operation, the frequency component of the noise changes, and a data analyzer can perform fault diagnosis on the equipment according to the change.
The mike of this patent can paste in the place that is close to the sound source as far as possible because small in size. On one hand, the low-frequency characteristics in the noise of the equipment are fully recorded by utilizing the near-field effect; on the other hand, the noise of the equipment is prevented from being mixed with other sounds of a test site, the data analysis difficulty is reduced, the reliability of noise diagnosis is improved, and misjudgment is avoided.
It should be noted that the data connector in embodiment 1 of the present invention may be designed at other positions on the microphone, or the data connector is not used, and the data line is directly led out from the microphone housing. The microphone profile may be formed in other shapes. The damping rubber can be replaced by other materials with damping effect, such as sponge, foam and the like. Other common portable devices with storage and computing capabilities, such as tablet computers, notebook computers, etc., can be used instead of mobile phones.
According to the microphone adhered to the surface of the industrial equipment, provided by the embodiment 1 of the invention, the movable adhesive is arranged on the microphone main body, so that the microphone can be directly adhered to the industrial equipment needing noise detection, the problem of inaccurate noise detection caused by a certain distance between the noise collection equipment and a sound source is reduced, meanwhile, a fixing support or a fixing hole is not required to be specially installed on the detected industrial equipment, and the damage to the equipment is reduced. In addition, the removable adhesive can be adhered and removed at any time, and the microphone adhered to the surface of the industrial equipment is small, exquisite and convenient to use.
Further, the terminal device comprises one of a smart phone, a pad, a PC and a handheld device.
The terminal equipment is connected with the terminal equipment, and the received noise information is sent to the cloud server by the terminal equipment for processing and storing;
or uploading a processing result obtained after the noise information is processed by the terminal equipment to a cloud server for storage.
A flow diagram of a noise detection method, comprising the steps of:
acquiring a noise signal of a preset time length acquired by a microphone adhered to the surface of detected equipment through a movable adhesive;
sending the noise signal to a terminal device through a data line connected with the microphone, and processing the noise information by adopting an intelligent processing and analysis algorithm pre-installed on the terminal device to obtain a processed signal;
and storing the processed signals on the terminal equipment or uploading the processed signals to a cloud server for storage.
Further, the intelligent processing and analysis algorithm comprises: the method comprises the following steps of convolutional neural network, expert system, particle swarm optimization, support vector machine, digital filtering algorithm, Fourier transform, logarithm processing algorithm and autocorrelation operation algorithm.
After the test point position on the surface of the equipment is determined, wiping the vicinity of the test point; then, terminal equipment such as a mobile phone and the like and a microphone (or called as a microphone) are connected together through a data line; sticking a removable adhesive on the surface of the damping rubber of the microphone, and sticking the microphone at the position of a test point on the surface of equipment; finally, recording about 15s of audio by using the mobile phone, and then selecting:
(1) using sound analysis and diagnosis software on the mobile phone to perform feature extraction calculation such as digital filtering, Fourier transform, logarithm processing, autocorrelation operation and the like on an audio file, and judging the running state of the equipment by combining information such as relevant parameters, running conditions and the like of the equipment;
(2) copying the audio file stored on the mobile phone and the recorded relevant parameters of the mechanical equipment to a computer, or sending the audio file and the recorded relevant parameters of the mechanical equipment to a cloud server through a network, and performing comprehensive judgment and fault prediction on the running state of the equipment by using intelligent algorithms such as a convolutional neural network, an expert system, particle swarm optimization, a support vector machine and the like.
Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (7)
1. A noise detection system is characterized by comprising a microphone capable of being pasted on detected equipment, terminal equipment provided with multiple intelligent processing and analysis algorithms, the detected equipment and a data line for connecting the microphone and the terminal; the microphone is adhered to the surface of the detected equipment, the terminal equipment receives noise data collected by the microphone through a data line, and the noise data is processed by adopting a pre-installed intelligent processing and analyzing algorithm;
the microphone comprises a microphone body (1), a sound transmission hole (2) fixed on the microphone body (1), a data connector (3) fixed on the top surface of the microphone body (1), a vibration damping rubber (4) arranged on the microphone body (1) and a removable rubber (5) arranged on the surface of the vibration damping rubber (4); a microphone (6) and a signal processing circuit board (7) are arranged in the microphone main body (1); the movable rubber (5) is used for being pasted on equipment to be detected, the vibration reduction rubber (4) is used for reducing the influence of vibration of mechanical equipment on sound collection, sound collected through the sound transmission holes (2) is transmitted into the signal processing circuit board (7) to be subjected to data processing and analysis, and the processed signals are output through the data connector (3).
2. The noise detection system according to claim 1, characterized in that the microphone body (1) is cubic or cylindrical;
when the microphone main body (1) is a cube, the sound transmission hole (2), the removable rubber (5) and the vibration reduction rubber (4) are all arranged on the same side face of the microphone main body (1), the sound transmission hole (2) is arranged at the lower part of the microphone main body (1), the vibration reduction rubber (4) is arranged at the upper part of the sound transmission hole (2), and the removable rubber (5) is arranged on the surface of the vibration reduction rubber (4);
when the microphone main body (1) is a cylinder, the sound transmission hole (2) and the vibration reduction rubber (4) are arranged on the bottom surface of the microphone main body (1); the vibration reduction rubber (4) and the movable rubber (5) are both circular rings, and the sound transmission hole (2) is formed in the center of each circular ring.
3. The noise detection system according to claim 1, wherein the signal processing circuit board (7) comprises an interface circuit, a signal preprocessing circuit, an analog-to-digital conversion circuit and a data transmission circuit which are connected in sequence; the interface circuit is electrically connected with the microphone (6).
4. The noise detection system of claim 3, wherein the signal preprocessing circuit comprises a filtering processing circuit and a pre-amplifying processing circuit; the analog-to-digital conversion circuit comprises a sampling circuit and a quantization and coding circuit; the data transmission circuit comprises a wired data transmission circuit and a wireless data transmission circuit.
5. The noise detection system of claim 4, wherein the wireless data transmission circuit comprises at least one of: 3G, 4G, 5G, WiFi, ZigBee.
6. The noise detection system of claim 1, wherein the terminal device comprises one of a smartphone, a pad, a PC, and a handheld device.
7. The noise detection system of claim 1, further comprising a cloud server, the cloud server being connected to the terminal device; the terminal equipment sends the received noise information to a cloud server for processing and storing;
or uploading a processing result obtained after the noise information is processed by the terminal equipment to a cloud server for storage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922383589.9U CN212007510U (en) | 2019-12-26 | 2019-12-26 | Noise detection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922383589.9U CN212007510U (en) | 2019-12-26 | 2019-12-26 | Noise detection system |
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| CN212007510U true CN212007510U (en) | 2020-11-24 |
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| CN201922383589.9U Active CN212007510U (en) | 2019-12-26 | 2019-12-26 | Noise detection system |
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