Low-frequency vibration acquisition equipment

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By designing a low-frequency vibration acquisition device including low-frequency vibration sensor, signal conditioning filter circuit and waterproof interface, the stability problems of the existing technology in low-frequency vibration signal acquisition and harsh environment are solved, and high efficiency and stability of large structures are achieved monitor.

CN119469378APending Publication Date: 2025-02-18SHENZHEN BORUICHUANG TECH CO LTD

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Patent Information

Application Number: CN202411934559.1
Authority / Receiving Office: CN · China
Patent Type: Applications(China)
Current Assignee / Owner
Filing Date: 2024-12-24
Publication Date: 2025-02-18

AI Technical Summary

Technical Problem

The prior art has poor results in low-frequency vibration signal acquisition, especially in long-term stable monitoring of large structures, and the stability and deployment convenience of equipment are insufficient in harsh environments outdoors or industrial sites.

Method used

A low-frequency vibration acquisition device was designed, including a housing, an Ethernet transceiver, a POE power supply, a processor, a low-frequency vibration sensor, an analog signal power supply and a signal conditioning filter circuit. It adopts a fully enclosed waterproof aluminum shell and an RJ45 waterproof interface, through a single network cable POE powered and data communication, equipped with a second-order Butterworth filter and a fully differential amplifier to improve signal quality.

Benefits of technology

It realizes efficient collection and processing of low-frequency vibration signals, ensures long-term stable operation and deployment convenience of equipment in harsh environments, and supports continuous monitoring and early warning of large structures.

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Abstract

The invention discloses a low-frequency vibration acquisition device which comprises a shell, an Ethernet transceiver, a POE power supply, a processor, a low-frequency vibration sensor, an analog signal power supply and a signal conditioning filter circuit, the Ethernet transceiver, the POE power supply, the processor, the low-frequency vibration sensor, the analog signal power supply and the signal conditioning filter circuit are arranged in the shell, and the shell is provided with a waterproof interface. The POE power supply is respectively connected with the analog signal power supply, the processor and the waterproof interface, the analog signal power supply is further connected with the low-frequency vibration sensor and the signal conditioning and filtering circuit, the processor is further connected with the signal filtering and conditioning circuit and the Ethernet transceiver, and the Ethernet transceiver is further connected with the waterproof interface. The low-frequency vibration acquisition equipment optimizes a low-frequency signal scene, is small and exquisite in structure and convenient to deploy, adopts single-network-cable POE power supply and data communication, adopts a totally-closed waterproof aluminum shell, can resist a severe working environment, and is beneficial to long-term stable continuous monitoring of a large-scale structure.

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Description

Technical Field

[0001] The invention relates to the technical field of low-frequency vibration collection, and in particular to a low-frequency vibration collection device. Background Art

[0002] With the development of modern technology, the design and construction of large-scale infrastructure are facing more and more challenges, including increasingly stringent requirements for long-term stability, reliability, and resistance to natural disasters. These scenarios require us to have the ability to continuously monitor large structures, monitor the status of the structures, and provide early warnings for various possible risks. Therefore, how to design, deploy, detect, and calculate sensors has become the focus of discussion.

[0003] The vibration frequencies that need to be detected in current large structures are very low, even below a few tenths of a Hz, and existing technologies are poor at collecting low-frequency signals.

[0004] In addition, the equipment itself has poor working stability and deployment convenience in harsh scenarios such as outdoor and industrial sites. Summary of the invention

[0005] The main purpose of the present invention is to propose a low-frequency vibration acquisition device for low-frequency signal scenarios, aiming to achieve long-term and stable continuous monitoring of large structures.

[0006] To achieve the above-mentioned purpose, the present invention provides a low-frequency vibration acquisition device, including: a shell, an Ethernet transceiver, a POE power supply, a processor, a low-frequency vibration sensor, an analog signal power supply and a signal conditioning and filtering circuit arranged in the shell, and a waterproof interface is provided on the shell, wherein the POE power supply is respectively connected to the analog signal power supply, the processor, and the waterproof interface, the analog signal power supply is also connected to the low-frequency vibration sensor and the signal conditioning and filtering circuit, the processor is also connected to the signal filtering and conditioning circuit and the Ethernet transceiver, and the Ethernet transceiver is also connected to the waterproof interface.

[0007] A further technical solution of the present invention is that the signal filtering and conditioning circuit includes two stages, the first stage is a second-order Butterworth filter circuit for improving the input impedance of the signal source, and the second stage is a fully differential amplifier and anti-aliasing filter circuit for driving the back-end ADC and preventing signal aliasing.

[0008] A further technical solution of the present invention is that the second-order Butterworth filter circuit includes an amplifier U1, an amplifier U2, an amplifier U3, an amplifier U4, a resistor R3, a resistor R4, a resistor R9, a resistor R10, a capacitor C2, a capacitor C5, a capacitor C8 and a capacitor C11;

[0009] Pin 3 of the amplifier U1 is connected to one end of the resistor R3 and pin 2 of the amplifier U1, the other end of the resistor R3 is connected to one end of the resistor R4 and one end of the capacitor C2, one end of the resistor R4 is connected to pin 1 of the amplifier U2 and one end of the capacitor C5, the other end of the capacitor C5 is grounded, and the other end of the capacitor C2 is connected to pin 3 of the amplifier U2, pin 2 of the amplifier U2, and the fully differential amplifier and anti-aliasing filter circuit;

[0010] Pin 3 of the amplifier U3 is connected to one end of the resistor R9 and pin 2 of the amplifier U3, the other end of the resistor R9 is connected to one end of the resistor R10 and one end of the capacitor C8, one end of the resistor R10 is connected to pin 1 of the amplifier U4 and one end of the capacitor C11, the other end of the capacitor C11 is grounded, and the other end of the capacitor C8 is connected to pin 3 of the amplifier U4, pin 2 of the amplifier U4 and the fully differential amplifier and anti-aliasing filter circuit.

[0011] A further technical solution of the present invention is that the fully differential amplifier and anti-aliasing filter circuit includes a resistor R5, a resistor R1, a resistor R6, a capacitor C1, a resistor R7, a resistor R8, a resistor R12, a capacitor C12, a capacitor C9, an amplifier U5, a capacitor C6, a capacitor C7 and a capacitor C10;

[0012] One end of the resistor R5 is connected to the pin 3 of the amplifier U2, and the other end is connected to the pin 1 of the amplifier U5, one end of the capacitor C1, and one end of the resistor R1. The other end of the capacitor C1 is connected to one end of the resistor R6 and the pin 2 of the amplifier U5. The other end of the resistor R1 is connected to the other end of the resistor R6, one end of the capacitor C7, and one end of the capacitor C6. The other end of the capacitor C6 is grounded.

[0013] One end of the resistor R7 is connected to the pin 3 of the amplifier U4, and the other end is connected to the pin 3 of the amplifier U5, one end of the capacitor C12, and one end of the resistor R12. The other end of the capacitor C12 is connected to one end of the resistor R8 and the pin 6 of the amplifier U5. The other end of the resistor R8 is connected to the other end of the resistor R12, the other end of the capacitor C7, and one end of the capacitor C10. The other end of the capacitor C10 is grounded.

[0014] One end of the capacitor C9 is connected to the pin 4 of the amplifier U5 , and the other end is connected to the pin 6 of the amplifier U5 .

[0015] A further technical solution of the present invention is that the analog signal power supply includes two stages, the first stage is a precision voltage reference source circuit, which is used to output the voltage reference required by the sensor, and the second stage is a low-pass filter circuit composed of a zero-drift precision operational amplifier, and is output through a transistor to enhance the driving capability.

[0016] A further technical solution of the present invention is that the precision voltage reference source circuit includes a voltage reference source element, a capacitor C1, a capacitor C2 and a capacitor C5;

[0017] Pin 1 of the voltage reference source element is connected to one end of the capacitor C1 and one end of the capacitor C2, the other end of the capacitor C1 and the other end of the capacitor C2 are grounded, pin 3 of the voltage reference source element is connected to one end of the capacitor C5 and grounded, pin 2 of the voltage reference source element is connected to the other end of the capacitor C5 and the low-pass filter circuit composed of the zero-drift precision operational amplifier.

[0018] A further technical solution of the present invention is that the low-pass filter circuit composed of the zero-drift precision operational amplifier includes an amplifier U6, a capacitor C3, a capacitor C4, a capacitor C6, a capacitor C7, a resistor R1, a resistor R2, a resistor R3 and a MOS tube Q;

[0019] Pin 1 of the amplifier U6 is connected to pin 2 of the voltage reference source element, pin 2 of the amplifier U6 is connected to one end of the capacitor C3 and one end of the capacitor C4, the other end of the capacitor C3 and the other end of the capacitor C4 are grounded, pin 3 of the amplifier U6 is connected to one end of the resistor R1 and one end of the capacitor C6, the other end of the capacitor C6 is connected to pin 5 of the amplifier U6 and one end of the resistor R2, pin 4 of the amplifier U6 is grounded, the other end of the resistor R1 is connected to the B pole of the MOS tube Q, the other end of the resistor R2 is connected to one end of the resistor R3, the E pole of the MOS tube Q, and one end of the capacitor C7, the other end of the resistor R3 is connected to the other end of the capacitor C7 and grounded.

[0020] A further technical solution of the present invention is that the housing comprises an upper cover and a lower cover, the upper cover is provided with a spirit level, a hole is opened on the surface of the upper cover, and the waterproof interface is arranged at the opening.

[0021] A further technical solution of the present invention is that a waterproof silicone ring is embedded at the connection between the upper cover and the lower cover.

[0022] A further technical solution of the present invention is that the waterproof interface is an RJ45 waterproof interface.

[0023] The low-frequency vibration acquisition equipment of the present invention is optimized for low-frequency signal scenarios, has a compact structure, is easy to deploy, uses a single network cable POE power supply and data communication, and has a fully enclosed waterproof aluminum shell, which can withstand harsh working environments and is conducive to long-term and stable continuous monitoring of large structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the exploded structure of a preferred embodiment of the low-frequency vibration collection device of the present invention;

[0026] Figure 2 It is a structural block diagram of a preferred embodiment of the low-frequency vibration acquisition device of the present invention;

[0027] Figure 3 It is a circuit structure diagram of a signal conditioning and filtering circuit;

[0028] Figure 4 It is a circuit structure diagram of analog signal power supply.

[0029] Description of Figure Numbers:

[0030] Housing 1; Ethernet transceiver 2; POE power supply 3; processor 4; low-frequency vibration sensor 5; analog signal power supply 6; signal conditioning and filtering circuit 7; waterproof interface 8; upper cover 9; lower cover 10; waterproof silicone ring 11.

[0031] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0034] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] The present invention proposes a low-frequency vibration collection device, such as Figures 1 to 4 As shown, a preferred embodiment of the low-frequency vibration acquisition device of the present invention includes a housing 1, an Ethernet transceiver 2, a POE power supply 3, a processor 4, a low-frequency vibration sensor 5, an analog signal power supply 6 and a signal conditioning and filtering circuit 7 arranged in the housing 1, and a waterproof interface 8 is provided on the housing 1, wherein the POE power supply 3 is respectively connected to the analog signal power supply 6, the processor 4, and the waterproof interface 8, the analog signal power supply 6 is also connected to the low-frequency vibration sensor 5 and the signal conditioning and filtering circuit 7, the processor 4 is also connected to the signal filtering and conditioning circuit and the Ethernet transceiver 2, and the Ethernet transceiver 2 is also connected to the waterproof interface 8.

[0036] In this embodiment, the housing 1 includes an upper cover 9 and a lower cover 10, which are integrally formed by CNC milling of a whole piece of aluminum, and the surface is conductively oxidized. A waterproof silicone ring 11 is embedded in the joint between the upper cover 9 and the lower cover 10 to achieve waterproofing.

[0037] In this embodiment, the low-frequency vibration sensor 5 measures the vibration signal in the vertical direction. In order to obtain accurate data, a level is embedded in the top of the upper cover 9 to assist the construction personnel in performing horizontal installation.

[0038] The surface of the upper cover 9 is provided with an opening for installing the waterproof interface 8. The waterproof interface 8 adopts the RJ45 waterproof interface 8 to achieve overall waterproof sealing, good electromagnetic shielding characteristics, good thermal conductivity characteristics, etc., thereby ensuring stable and reliable operation of the equipment in various extreme environments.

[0039] The present invention uses the RJ45 waterproof interface 8 to seal the Ethernet transceiver and the POE power supply 3, reduces the number of external interfaces, and thus reduces the risk of sealing failure, can achieve a 100Mbps communication rate over a long distance, and ensures the flexibility of equipment deployment.

[0040] In this embodiment, the frequency response range of the low-frequency vibration sensor 5 to the vibration signal is 0-550Hz, so it is necessary to add a signal filtering and conditioning circuit to filter out interference and noise outside the frequency band. The signal filtering and conditioning circuit includes two stages. The first stage is a second-order Butterworth filter circuit, which is used to increase the input impedance of the signal source, with a cut-off frequency of 6kHz and a band-stop frequency of 340kHz (-70dB). The second stage is a fully differential amplifier and anti-aliasing filter circuit, which is used to drive the back-end ADC and prevent signal aliasing.

[0041] Specifically, the second-order Butterworth filter circuit includes an amplifier U1, an amplifier U2, an amplifier U3, an amplifier U4, a resistor R3, a resistor R4, a resistor R9, a resistor R10, a capacitor C2, a capacitor C5, a capacitor C8 and a capacitor C11.

[0042] Pin 3 of amplifier U1 is connected to one end of resistor R3 and pin 2 of amplifier U1, the other end of resistor R3 is connected to one end of resistor R4 and one end of capacitor C2, one end of resistor R4 is connected to pin 1 of amplifier U2 and one end of capacitor C5, the other end of capacitor C5 is grounded, and the other end of capacitor C2 is connected to pin 3 of amplifier U2, pin 2 of amplifier U2 and the fully differential amplifier and anti-aliasing filter circuit.

[0043] Pin 3 of amplifier U3 is connected to one end of resistor R9 and pin 2 of amplifier U3, the other end of resistor R9 is connected to one end of resistor R10 and one end of capacitor C8, one end of resistor R10 is connected to pin 1 of amplifier U4 and one end of capacitor C11, the other end of capacitor C11 is grounded, and the other end of capacitor C8 is connected to pin 3 of amplifier U4, pin 2 of amplifier U4 and the fully differential amplifier and anti-aliasing filter circuit.

[0044] In this embodiment, the fully differential amplifier and anti-aliasing filter circuit includes a resistor R5, a resistor R1, a resistor R6, a capacitor C1, a resistor R7, a resistor R8, a resistor R12, a capacitor C12, a capacitor C9, an amplifier U5, a capacitor C6, a capacitor C7 and a capacitor C10.

[0045] One end of resistor R5 is connected to pin 3 of amplifier U2, and the other end is connected to pin 1 of amplifier U5, one end of capacitor C1, and one end of resistor R1. The other end of capacitor C1 is connected to one end of resistor R6 and pin 2 of amplifier U5. The other end of resistor R1 is connected to the other end of resistor R6, one end of capacitor C7, and one end of capacitor C6. The other end of capacitor C6 is grounded.

[0046] One end of resistor R7 is connected to pin 3 of amplifier U4, and the other end is connected to pin 3 of amplifier U5, one end of capacitor C12, and one end of resistor R12. The other end of capacitor C12 is connected to one end of resistor R8 and pin 6 of amplifier U5. The other end of resistor R8 is connected to the other end of resistor R12, the other end of capacitor C7, and one end of capacitor C10. The other end of capacitor C10 is grounded.

[0047] One end of the capacitor C9 is connected to the pin 4 of the amplifier U5, and the other end is connected to the pin 6 of the amplifier U5.

[0048] In this embodiment, the analog signal power supply 6 includes two stages. The first stage is a precision voltage reference source circuit for outputting the voltage reference required by the sensor. The second stage is a low-pass filter circuit composed of a zero-drift precision operational amplifier, and is output through a transistor to enhance the driving capability, thereby providing the sensor with a low-noise, stable, and precise voltage reference and power supply capability.

[0049] Specifically, the precision voltage reference source circuit includes a voltage reference source element, a capacitor C1, a capacitor C2, and a capacitor C5.

[0050] Pin 1 of the voltage reference source component is connected to one end of capacitor C1 and one end of capacitor C2, the other end of capacitor C1 and the other end of capacitor C2 are grounded, pin 3 of the voltage reference source component is connected to one end of capacitor C5 and grounded, pin 2 of the voltage reference source component is connected to the other end of capacitor C5, and a low-pass filter circuit composed of a zero-drift precision operational amplifier.

[0051] The low-pass filter circuit composed of a zero-drift precision operational amplifier includes an amplifier U6, a capacitor C3, a capacitor C4, a capacitor C6, a capacitor C7, a resistor R1, a resistor R2, a resistor R3 and a MOS tube Q.

[0052] Pin 1 of amplifier U6 is connected to pin 2 of the voltage reference source element, pin 2 of amplifier U6 is connected to one end of capacitor C3 and one end of capacitor C4, the other end of capacitor C3 and the other end of capacitor C4 are grounded, pin 3 of amplifier U6 is connected to one end of resistor R1 and one end of capacitor C6, the other end of capacitor C6 is connected to pin 5 of amplifier U6 and one end of resistor R2, pin 4 of amplifier U6 is grounded, the other end of resistor R1 is connected to the B pole of MOS tube Q, the other end of resistor R2 is connected to one end of resistor R3, the E pole of MOS tube Q and one end of capacitor C7, the other end of resistor R3 is connected to the other end of capacitor C7 and grounded.

[0053] The low-frequency vibration acquisition equipment of the present invention is optimized for low-frequency signal scenarios, has a compact structure, is easy to deploy, uses a single network cable POE power supply and data communication, and has a fully enclosed waterproof aluminum shell, which can withstand harsh working environments and is conducive to long-term and stable continuous monitoring of large structures.

[0054] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A low-frequency vibration collection device, characterized in that: include: A shell, an Ethernet transceiver, a POE power supply, a processor, a low-frequency vibration sensor, an analog signal power supply and a signal conditioning and filtering circuit are arranged in the shell, and a waterproof interface is arranged on the shell, wherein the POE power supply is respectively connected to the analog signal power supply, the processor and the waterproof interface, the analog signal power supply is also connected to the low-frequency vibration sensor and the signal conditioning and filtering circuit, the processor is also connected to the signal filtering and conditioning circuit and the Ethernet transceiver, and the Ethernet transceiver is also connected to the waterproof interface.

2. The low-frequency vibration acquisition device according to claim 1, characterized in that: The signal filtering and conditioning circuit includes two stages, the first stage is a second-order Butterworth filter circuit for improving the input impedance of the signal source, and the second stage is a fully differential amplifier and anti-aliasing filter circuit for driving the back-end ADC and preventing signal aliasing.

3. The low-frequency vibration acquisition device according to claim 2, characterized in that: The second-order Butterworth filter circuit includes an amplifier U1, an amplifier U2, an amplifier U3, an amplifier U4, a resistor R3, a resistor R4, a resistor R9, a resistor R10, a capacitor C2, a capacitor C5, a capacitor C8 and a capacitor C11; Pin 3 of the amplifier U1 is connected to one end of the resistor R3 and pin 2 of the amplifier U1, the other end of the resistor R3 is connected to one end of the resistor R4 and one end of the capacitor C2, one end of the resistor R4 is connected to pin 1 of the amplifier U2 and one end of the capacitor C5, the other end of the capacitor C5 is grounded, and the other end of the capacitor C2 is connected to pin 3 of the amplifier U2, pin 2 of the amplifier U2, and the fully differential amplifier and anti-aliasing filter circuit; Pin 3 of the amplifier U3 is connected to one end of the resistor R9 and pin 2 of the amplifier U3, the other end of the resistor R9 is connected to one end of the resistor R10 and one end of the capacitor C8, one end of the resistor R10 is connected to pin 1 of the amplifier U4 and one end of the capacitor C11, the other end of the capacitor C11 is grounded, and the other end of the capacitor C8 is connected to pin 3 of the amplifier U4, pin 2 of the amplifier U4 and the fully differential amplifier and anti-aliasing filter circuit.

4. The low-frequency vibration acquisition device according to claim 3, characterized in that: The fully differential amplifier and anti-aliasing filter circuit includes a resistor R5, a resistor R1, a resistor R6, a capacitor C1, a resistor R7, a resistor R8, a resistor R12, a capacitor C12, a capacitor C9, an amplifier U5, a capacitor C6, a capacitor C7 and a capacitor C10; One end of the resistor R5 is connected to the pin 3 of the amplifier U2, and the other end is connected to the pin 1 of the amplifier U5, one end of the capacitor C1, and one end of the resistor R1. The other end of the capacitor C1 is connected to one end of the resistor R6 and the pin 2 of the amplifier U5. The other end of the resistor R1 is connected to the other end of the resistor R6, one end of the capacitor C7, and one end of the capacitor C6. The other end of the capacitor C6 is grounded. One end of the resistor R7 is connected to the pin 3 of the amplifier U4, and the other end is connected to the pin 3 of the amplifier U5, one end of the capacitor C12, and one end of the resistor R12. The other end of the capacitor C12 is connected to one end of the resistor R8 and the pin 6 of the amplifier U5. The other end of the resistor R8 is connected to the other end of the resistor R12, the other end of the capacitor C7, and one end of the capacitor C10. The other end of the capacitor C10 is grounded. One end of the capacitor C9 is connected to the pin 4 of the amplifier U5 , and the other end is connected to the pin 6 of the amplifier U5 .

5. The low-frequency vibration acquisition device according to claim 4, characterized in that: The analog signal power supply includes two stages. The first stage is a precision voltage reference source circuit for outputting the voltage reference required by the sensor. The second stage is a low-pass filter circuit composed of a zero-drift precision operational amplifier, and is output through a transistor to enhance the driving capability.

6. The low-frequency vibration acquisition device according to claim 5, characterized in that: The precision voltage reference source circuit comprises a voltage reference source element, a capacitor C1, a capacitor C2 and a capacitor C5; Pin 1 of the voltage reference source element is connected to one end of the capacitor C1 and one end of the capacitor C2, the other end of the capacitor C1 and the other end of the capacitor C2 are grounded, pin 3 of the voltage reference source element is connected to one end of the capacitor C5 and grounded, pin 2 of the voltage reference source element is connected to the other end of the capacitor C5 and the low-pass filter circuit composed of the zero-drift precision operational amplifier.

7. The low-frequency vibration acquisition device according to claim 6, characterized in that: The low-pass filter circuit composed of the zero-drift precision operational amplifier includes an amplifier U6, a capacitor C3, a capacitor C4, a capacitor C6, a capacitor C7, a resistor R1, a resistor R2, a resistor R3 and a MOS tube Q; Pin 1 of the amplifier U6 is connected to pin 2 of the voltage reference source element, pin 2 of the amplifier U6 is connected to one end of the capacitor C3 and one end of the capacitor C4, the other end of the capacitor C3 and the other end of the capacitor C4 are grounded, pin 3 of the amplifier U6 is connected to one end of the resistor R1 and one end of the capacitor C6, the other end of the capacitor C6 is connected to pin 5 of the amplifier U6 and one end of the resistor R2, pin 4 of the amplifier U6 is grounded, the other end of the resistor R1 is connected to the B pole of the MOS tube Q, the other end of the resistor R2 is connected to one end of the resistor R3, the E pole of the MOS tube Q, and one end of the capacitor C7, the other end of the resistor R3 is connected to the other end of the capacitor C7 and grounded.

8. The low-frequency vibration acquisition device according to claim 1, characterized in that: The housing comprises an upper cover and a lower cover, the upper cover is provided with a level gauge, a hole is opened on the surface of the upper cover, and the waterproof interface is arranged at the hole.

9. The low-frequency vibration collection device according to claim 8, characterized in that: A waterproof silicone ring is embedded at the connection between the upper cover and the lower cover.

10. The low-frequency vibration acquisition device according to claim 1, characterized in that: The waterproof interface is an RJ45 waterproof interface.