Noise reduction electret microphone device for generator detection

Abstract

The utility model discloses a noise reduction electret microphone device for generator detection, which comprises an electret microphone, the positive electrode of the electret microphone is connected with one terminal of a first resistor, and the other terminal of the first resistor is used for being connected with the positive electrode of a power supply; the negative electrode of the electret microphone is connected with one terminal of the first capacitor, and the other terminal of the first capacitor is connected with the non-inverting input end of the operational amplifier; the inverting input end of the operational amplifier is connected with one terminal of the second resistor, and the other terminal of the second resistor is connected with the GND; the output end of the operational amplifier is connected with the positive electrode of the second capacitor, and the negative electrode of the second capacitor is connected with GND; the signal end of the signal output plug is connected to the positive electrode of the second capacitor, and the sleeve end is connected to the GND. The device can overcome the noise interference in the production environment of the generator set through the improved electroacoustic equipment, thereby remarkably improving the signal acquisition capability in the high-noise environment.

Description

Technical Field

[0001] The utility model relates to the technical field of generator audio detection, in particular to a noise reduction electret microphone device for generator detection. Background Art

[0002] During generator set inspection, accurately capturing the acoustic signals from the generator's internal operation is crucial for monitoring equipment status. However, traditional microphones are susceptible to interference in high-noise environments, resulting in reduced reliability of detection results. Therefore, to address the challenges encountered during actual production and maintenance, there is an urgent need for a microphone device that can accurately capture acoustic signals in noisy environments.

[0003] Chinese patent document CN207692060U, published / announced on August 3, 2018, discloses a microphone switch detection circuit and microphone signal amplification circuit, including an operational amplifier U1D, resistors R1, R2, R3, and R4. One end of resistor R1 is connected to a first power supply terminal, and the other end of resistor R1 is connected to ground via resistor R3. The other end of resistor R1 is connected to the positive-phase terminal of operational amplifier U1D, and the microphone interface is connected to the negative-phase terminal of operational amplifier U1D via resistor R2. The output of operational amplifier U1D is connected to the microphone enable terminal via resistor R4. This circuit features detection of microphone on / off status, allowing subsequent circuits to process the microphone input signal, such as enabling the microphone audio output by switching the switch. However, this circuit has a disadvantage: it cannot accurately capture sound signals in noisy environments, resulting in poor signal acquisition capabilities when used in noisy environments. Utility Model Content

[0004] The purpose of the utility model is to provide a noise-reducing electret microphone device for generator detection, which can overcome the noise interference in the generator set production environment through improved electroacoustic equipment, thereby significantly improving the signal acquisition capability in a high-noise environment.

[0005] To achieve the above objectives, the present invention provides a noise-reducing electret microphone device for generator detection, comprising a first resistor, an electret microphone, a first capacitor, a second resistor, an operational amplifier, the second capacitor, and a signal output plug; the positive electrode of the electret microphone is connected to one terminal of the first resistor, and the other terminal of the first resistor is used to be connected to the positive electrode of a power supply; the negative electrode of the electret microphone is connected to one terminal of the first capacitor, and the other terminal of the first capacitor is connected to the non-inverting input terminal of the operational amplifier; the inverting input terminal of the operational amplifier is connected to one terminal of the second resistor, and the other terminal of the second resistor is connected to GND; the output terminal of the operational amplifier is connected to the positive electrode of the second capacitor, and the negative electrode of the second capacitor is connected to GND; the signal terminal of the signal output plug is connected to the positive electrode of the second capacitor, and the sleeve end is connected to GND.

[0006] A potentiometer is also included, wherein the output end of the operational amplifier is connected to one terminal of the potentiometer, and the other terminal of the potentiometer is connected to the positive electrode of the second capacitor.

[0007] The resistance of the first resistor is 2kΩ-10kΩ, the capacitance of the first capacitor is 10μF, the resistance of the second resistor is 10kΩ, and the capacitance of the second capacitor is 10μF.

[0008] The resistance range of the potentiometer is 1 kΩ~10 kΩ.

[0009] The power source is a 9V battery.

[0010] The invention also comprises a shielding shell, in which the electronic components are installed.

[0011] Compared with the prior art, the present invention has the following technical effects:

[0012] This utility model, through improved electroacoustic equipment, can overcome noise interference in generator set production environments and significantly improve signal acquisition capabilities in high-noise environments. In generator detection applications, the audio signal collected by the electret microphone, after noise reduction and amplification by this application, is processed by a host computer to reflect the internal operating status of the generator in real time. Operators can monitor changes in the generator's sound through the host computer interface, identify abnormal noise or vibration, and take proactive maintenance measures to prevent equipment failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art description:

[0014] Figure 1 This is a circuit diagram of the utility model, showing the connection relationship between the various components;

[0015] Figure 2 This is a circuit diagram of the inverting input terminal and the non-inverting input terminal of the operational amplifier of the utility model, showing the connection of each input terminal;

[0016] Figure 3 This is a circuit diagram of the output end of the operational amplifier of the present invention.

[0017] Reference numerals:

[0018] First resistor 1, electret microphone 2, first capacitor 3, second resistor 4, operational amplifier 5, inverting input terminal 51, non-inverting input terminal 52, output terminal 53, potentiometer 6, second capacitor 7, signal output plug 8, sound card 9. DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0020] See Figure 1-3 A noise reduction electret microphone device for generator detection includes a first resistor 1, an electret microphone 2, a first capacitor 3, a second resistor 4, an operational amplifier 5, a second capacitor 7, and a signal output plug 8; the positive electrode of the electret microphone 2 is connected to one terminal of the first resistor 1, and the other terminal of the first resistor 1 is used to be connected to the positive electrode of the power supply; the negative electrode of the electret microphone 2 is connected to one terminal of the first capacitor 3, and the other terminal of the first capacitor 3 is connected to the non-inverting input terminal 52 of the operational amplifier 5; the inverting input terminal 51 of the operational amplifier 5 is connected to one terminal of the second resistor 4, and the other terminal of the second resistor 4 is connected to GND; the output terminal 53 of the operational amplifier 5 is connected to the positive electrode of the second capacitor 7, and the negative electrode of the second capacitor 7 is connected to GND; the signal end of the signal output plug 8 is connected to the positive electrode of the second capacitor 7, and the sleeve end is connected to GND.

[0021] an electret microphone 2, for receiving the sound signal generated by the knocking generator;

[0022] Operational amplifier 5, which is LM358 or TL072, is used to amplify the sound signal received by the electret microphone;

[0023] A power supply, used to supply power to the electret microphone 5 and the operational amplifier 5;

[0024] A circuit network of capacitors and resistors used to filter and bias the sound signal;

[0025] The output plug 8 is used to transmit the amplified sound signal to an external device. Preferably, the output plug 8 is a 3.5mm plug.

[0026] The electret microphone 2 is the core sound sensor, used to collect the sound signal generated by the generator. It converts the sound waves into weak electrical signals, which serve as the starting point of the entire audio processing chain.

[0027] The operational amplifier 5 is used to amplify the weak electrical signal output by the electret microphone to increase the signal strength to be suitable for subsequent processing. It also provides impedance conversion, reducing the output impedance of the signal and facilitating signal transmission.

[0028] The first resistor 1 is used to provide a bias current for the electret microphone 2 to ensure the normal operation of the electret microphone 2 .

[0029] The second resistor 4 is connected between the inverting input terminal 51 of the operational amplifier 5 and the ground, and is used to set the gain and stable working state of the operational amplifier 5 .

[0030] The first capacitor 3 is used to couple the electret microphone 2 and the non-inverting input terminal 52 of the operational amplifier 5 to prevent a direct current from passing through while transmitting an audio signal.

[0031] The second capacitor 7 is used for filtering and signal coupling and is connected between the output terminal 53 of the operational amplifier 5 and the signal output plug 8 to ensure the stability and quality of the signal and prevent the DC component from entering the host computer device.

[0032] The power supply provides the required DC operating voltage to the electret microphone 2 and the operational amplifier 5 to ensure the normal operation of the entire circuit.

[0033] Through the above structure, the device, through improved electroacoustic equipment, can overcome the noise interference in the generator set production environment, thereby significantly improving the signal acquisition capability in high-noise environments. In the generator detection application, the audio signal collected by the electret microphone 2, after noise reduction and amplification in this application, is processed by the host computer and can reflect the internal operating status of the generator in real time. The operator can monitor the sound changes of the generator through the host computer interface, identify abnormal noise or vibration, and take maintenance measures in advance to prevent equipment failure.

[0034] Furthermore, the device further comprises a potentiometer 6 . The output terminal 53 of the operational amplifier 5 is connected to one terminal of the potentiometer 6 , and the other terminal of the potentiometer 6 is connected to the positive electrode of the second capacitor 7 .

[0035] The potentiometer 6 is used to adjust the volume of the output signal of the operational amplifier 5. By changing the resistance value of the potentiometer 6, the amplitude of the output signal can be controlled to meet the requirements of different input devices.

[0036] Specifically, in this embodiment, the resistance of the first resistor 1 is 2 kΩ-10 kΩ, the capacitance of the first capacitor 3 is 10 μF, the resistance of the second resistor 4 is 10 kΩ, and the capacitance of the second capacitor 7 is 10 μF.

[0037] The resistance range of the potentiometer 6 is 1 kΩ to 10 kΩ.

[0038] The power source is a 9V battery.

[0039] The present invention further includes a shielded housing within which the electronic components are mounted. This serves to reduce electromagnetic interference and improve signal acquisition accuracy. The shielded housing is typically made of sheet metal and includes a hole for the electret microphone 2 to receive sound. It also houses a cable connected to the output plug 8.

[0040] The working principle of this utility model:

[0041] After the electret microphone 2 converts the collected sound signals into weak electrical signals, these signals need to be amplified and processed so that a host computer, usually a computer or similar device, can analyze and process them.

[0042] Signal amplification process:

[0043] First, the electrical signal output by electret microphone 2 requires amplification and impedance conversion due to its extremely low voltage and high impedance. This process is accomplished by operational amplifier 5. Operational amplifier 5 amplifies the weak electrical signal to a level suitable for further processing and reduces the signal's output impedance, making it easier to transmit.

[0044] Specifically, the output of electret microphone 2 is connected via capacitor C1 to the non-inverting input (+) of operational amplifier 5. The output signal of operational amplifier 5 passes through potentiometer R3 to control the output volume, is filtered and coupled via another capacitor C2, and is ultimately output to the signal terminal of a 3.5mm jack.

[0045] Signal transmission to the host computer:

[0046] The amplified audio signal is transmitted to the computer's sound card 9 via a 3.5mm jack. Sound card 9 serves as an input device for the host computer, receiving external audio signals. The computer's sound card converts these analog signals into digital signals for further processing and analysis in the software.

[0047] Signal processing of the host computer:

[0048] Once the sound signal enters the host computer, it can be recognized and processed by various audio processing software. The host computer can perform the following main tasks:

[0049] 1. Real-time monitoring and analysis: The host computer can display the waveform, spectrum, and other characteristics of the audio signal in real time, allowing users to monitor and analyze signal quality and content. For example, in a generator inspection scenario, the host computer can monitor whether the equipment is operating normally.

[0050] 2. Filtering and noise reduction: The host computer software can filter the audio signal to remove background noise or unwanted frequency components, thereby enhancing the effective components of the signal. This is especially important for signal acquisition in high-noise environments.

[0051] 3. Signal storage and playback: The host computer can record and store the received audio signals as files for subsequent analysis or playback. This allows analysis and comparison of historical data, helping to identify abnormalities in equipment operation.

[0052] 4. Pattern recognition and fault detection: Using machine learning algorithms or other intelligent analysis tools, the host computer can perform pattern recognition on the collected audio signals and automatically detect possible faults or anomalies. For example, by analyzing the sound patterns inside a generator, potential mechanical failures or abnormal operating conditions can be detected.

[0053] In generator monitoring applications, the audio signal collected by the electret microphone 2, after amplification and processing by the host computer, can reflect the generator's internal operating status in real time. Operators can monitor changes in the generator's sound through the host computer interface, identify abnormal noise or vibration, and take proactive maintenance measures to prevent equipment failure.

Claims

1. A noise-reducing electret microphone device for generator detection, characterized in that: It comprises a first resistor (1), an electret microphone (2), a first capacitor (3), a second resistor (4), an operational amplifier (5), a second capacitor (7) and a signal output plug (8); The positive electrode of the electret microphone (2) is connected to one terminal of the first resistor (1), and the other terminal of the first resistor (1) is used to be connected to the positive electrode of the power supply; the negative electrode of the electret microphone (2) is connected to one terminal of the first capacitor (3), and the other terminal of the first capacitor (3) is connected to the non-inverting input terminal (52) of the operational amplifier (5); The inverting input terminal (51) of the operational amplifier (5) is connected to one terminal of the second resistor (4), and the other terminal of the second resistor (4) is connected to GND; the output terminal (53) of the operational amplifier (5) is connected to the positive electrode of the second capacitor (7), and the negative electrode of the second capacitor (7) is connected to GND; The signal end of the signal output plug (8) is connected to the positive electrode of the second capacitor (7), and the sleeve end is connected to GND.

2. The noise reduction electret microphone device for generator detection according to claim 1, characterized in that: It also includes a potentiometer (6), the output end (53) of the operational amplifier (5) is connected to one terminal of the potentiometer (6), and the other terminal of the potentiometer (6) is connected to the positive electrode of the second capacitor (7).

3. The noise reduction electret microphone device for generator detection according to claim 1, characterized in that: The resistance of the first resistor (1) is 2 kΩ to 10 kΩ, the capacitance of the first capacitor (3) is 10 μF, the resistance of the second resistor (4) is 10 kΩ, and the capacitance of the second capacitor (7) is 10 μF.

4. The noise reduction electret microphone device for generator detection according to claim 2, characterized in that: The resistance range of the potentiometer (6) is 1 kΩ to 10 kΩ.

5. The noise reduction electret microphone device for generator detection according to claim 1, characterized in that: The power source is a 9V battery.

6. A noise reduction electret microphone device for generator detection according to claim 1 or 2, characterized in that: The invention also comprises a shielding shell, in which the electronic components are installed.

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