An anti-interference accelerometer

Abstract

This invention discloses an anti-interference accelerometer, comprising a main assembly including a base, an externally threaded connecting cylinder, a housing, a shielding layer, a mounting bracket, a sensing element, a plastic column, screws, and a temperature sensor. The externally threaded connecting cylinder is welded to the outer side of the upper surface of the base. This invention forms a double electromagnetic shielding space through the externally threaded connecting cylinder and the copper foil shielding layer on the inner wall of the housing. The shielding layer is welded to the housing to form a grounding loop, effectively blocking and exporting electromagnetic interference signals, thus enhancing anti-electromagnetic interference capability. Multiple elastic pads on the base provide buffer support for the sensing element, reducing the impact of mechanical vibration on the sensing element and improving measurement stability under vibration environments. The temperature sensor monitors the ambient temperature in real time, and the compensation circuit module uses a compensation algorithm based on the temperature characteristic curve to eliminate the interference of temperature changes on the output signal of the sensing element, ensuring measurement accuracy at different temperatures.

Description

Technical Field

[0001] This utility model relates to the field of sensor technology, specifically to an anti-interference acceleration sensor. Background Technology

[0002] Accelerometers, as devices capable of measuring acceleration, have wide applications in numerous fields such as industrial production, automotive electronics, aerospace, and smart wearables. In industrial production, they are used to monitor the operating status of mechanical equipment, such as vibration monitoring and fault diagnosis; in automotive electronics, they are used for airbag triggering and vehicle dynamic stability control systems; in aerospace, they play a crucial role in aircraft attitude control and navigation positioning; and in smart wearable devices, they can also realize functions such as motion monitoring and step counting. However, in practical use, accelerometers are often affected by various interferences, leading to decreased measurement accuracy, signal distortion, or even sensor malfunction.

[0003] Some existing accelerometers employ shielding measures to reduce electromagnetic interference, such as adding a metal shielding layer to the sensor housing; or using filtering circuits to process the signal to remove noise interference. However, these methods have certain limitations. For example, the metal shielding layer may not completely shield complex electromagnetic interference, and the filtering circuit may attenuate the useful signal while removing noise. Moreover, the effect on mechanical vibration interference and temperature change interference is not ideal. Therefore, an anti-interference accelerometer is proposed. Utility Model Content

[0004] The purpose of this invention is to provide an anti-interference acceleration sensor to solve one of the problems mentioned in the background art.

[0005] This utility model is implemented by the following technical solution: an anti-interference acceleration sensor, including a main component, the main component including a base, an external threaded connecting cylinder, a shell, a shielding layer, a mounting bracket, a sensing element, a plastic column, screws, a circuit board, a support frame and a temperature sensor;

[0006] The outer side of the upper surface of the base is welded with an external threaded connecting cylinder, and the outer wall of the external threaded connecting cylinder is threaded to a shell. The inner walls of both the external threaded connecting cylinder and the shell are fixedly connected with shielding layers. A sensing element is fixedly connected to the center of the upper surface of the base via a mounting bracket. The sensing element is located within the space enclosed by the shielding layer. Two plastic pillars are fixedly connected to the side of the upper surface of the base near the mounting bracket. Circuit boards are fixedly connected to the tops of the two plastic pillars via screws. A temperature sensor is fixedly connected to the other side of the upper surface of the base near the mounting bracket via a support frame.

[0007] As a further preferred embodiment of this technical solution: multiple elastic pads are fixedly connected to the outer side of the center of the upper surface of the base, and the tops of the multiple elastic pads are all attached to the bottom of the sensing element.

[0008] As a further preferred embodiment of this technical solution: a compensation circuit module is provided on the front of the upper surface of the circuit board, and the compensation circuit module forms a loop with the temperature sensor and the sensing element through wires.

[0009] As a further preferred embodiment of this technical solution: a signal processing circuit module is provided in the middle of the upper surface of the circuit board, and the signal processing circuit module is electrically connected to the sensing element.

[0010] As a further preferred embodiment of this technical solution: the shielding layer is made of copper foil, and the shielding layer is welded to the inner wall of the outer shell to form a grounding circuit.

[0011] As a further preferred embodiment of this technical solution, a connector is provided on the front part of the outer side wall of the outer casing.

[0012] As a further preferred embodiment of this technical solution: a sealing gasket is attached to the upper surface of the base near the outer side of the external threaded connecting cylinder, and the top of the sealing gasket is attached to the lower surface of the outer shell.

[0013] As a further preferred embodiment of this technical solution: mounting feet are welded to both sides of the base, and mounting holes are provided at the center of the upper surface of the mounting feet.

[0014] Advantages of this utility model:

[0015] 1. This utility model forms a double electromagnetic shielding space by connecting the external threaded cylinder and the copper foil shielding layer on the inner side wall of the outer shell, and the shielding layer is welded to the outer shell to form a grounding circuit, which effectively blocks and outputs electromagnetic interference signals, and enhances the anti-electromagnetic interference capability.

[0016] 2. This utility model uses multiple elastic rubber pads on the base to form a buffer support for the sensing element, reducing the impact of mechanical vibration on the sensing element and improving the measurement stability under vibration environment;

[0017] 3. This utility model uses a temperature sensor to monitor the ambient temperature in real time, and with the compensation circuit module based on the temperature characteristic curve compensation algorithm, it eliminates the interference of temperature changes on the output signal of the sensing element, ensuring measurement accuracy at different temperatures. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0020] Figure 2 This is a schematic diagram of the overall cross-sectional structure of this utility model;

[0021] Figure 3 This is a schematic diagram of the sensing element and circuit board structure of this utility model;

[0022] Figure 4 This is a schematic diagram of the base and plastic column structure of this utility model.

[0023] In the diagram: 1. Main component; 11. Base; 12. External threaded connecting cylinder; 13. Outer shell; 14. Shielding layer; 15. Mounting bracket; 16. Sensing element; 17. Elastic rubber pad; 18. Plastic column; 19. Screw; 20. Circuit board; 21. Support frame; 22. Temperature sensor; 23. Compensation circuit module; 24. Signal processing circuit module; 25. Connector; 26. Sealing gasket; 27. Mounting foot; 28. Mounting hole. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Example

[0026] Please see Figures 1-4 This utility model provides a technical solution: an anti-interference acceleration sensor, including a main component 1, which includes a base 11, an external threaded connecting cylinder 12, a shell 13, a shielding layer 14, a mounting bracket 15, a sensing element 16, a plastic column 18, a screw 19, a circuit board 20, a support frame 21, and a temperature sensor 22.

[0027] A threaded connecting cylinder 12 is welded to the outer side of the upper surface of the base 11. A shell 13 is threaded to the outer wall of the threaded connecting cylinder 12. A shielding layer 14 is fixedly connected to the inner side wall of both the threaded connecting cylinder 12 and the shell 13. A sensing element 16 is fixedly connected to the center of the upper surface of the base 11 via a mounting bracket 15. The sensing element 16 is located within the space enclosed by the shielding layer 14. Two plastic pillars 18 are fixedly connected to the side of the upper surface of the base 11 near the mounting bracket 15. A circuit board 20 is fixedly connected to the top of the two plastic pillars 18 via screws 19. A temperature sensor 22 is fixedly connected to the other side of the upper surface of the base 11 near the mounting bracket 15 via a support frame 21.

[0028] The outer shell 13 is made of high-strength, corrosion-resistant metal materials, such as aluminum alloy, which has good shielding performance and can effectively block external electromagnetic interference. The surface of the outer shell 13 is treated with special insulation to further improve its anti-interference ability. The sensing element 16 is manufactured using advanced MEMS (microelectromechanical systems) technology and has the characteristics of high precision and high sensitivity. It can accurately detect changes in acceleration and convert them into electrical signal output.

[0029] In this embodiment, specifically: multiple elastic pads 17 are fixedly connected to the outer side of the center of the upper surface of the base 11, and the tops of the multiple elastic pads 17 are all attached to the bottom of the sensing element 16; when the sensor is subjected to mechanical vibration, the elastic pads 17 play a buffering and shock-absorbing role through their own elastic deformation, reducing the impact of vibration on the sensing element 16, thereby ensuring that the sensing element 16 can accurately detect the target acceleration.

[0030] In this embodiment, specifically: a compensation circuit module 23 is provided on the front of the upper surface of the circuit board 20, and the compensation circuit module 23 forms a loop with the temperature sensor 22 and the sensing element 16 through wires;

[0031] The temperature compensation circuit uses a compensation algorithm based on the temperature characteristic curve of the sensing element 16, assuming that the output signal of the sensing element 16 at temperature t is U. t The output signal at standard temperature t0 is U t0 If the temperature coefficient is k, then the compensated signal is:

[0032] U comp =U t -k×(t-t0);

[0033] In this way, the influence of temperature changes on the output signal of the sensing element 16 can be eliminated, ensuring the accuracy of measurements under different temperature conditions.

[0034] In this embodiment, specifically: a signal processing circuit module 24 is provided in the middle of the upper surface of the circuit board 20, and the signal processing circuit module 24 is electrically connected to the sensing element 16.

[0035] The signal output terminal of the sensing element 16 is electrically connected to the signal input terminal of the signal processing circuit module 24; the signal processing circuit module 24 includes an amplifier circuit, a filter circuit, and an analog-to-digital converter circuit.

[0036] The amplifier circuit is used to amplify the weak electrical signal output by the sensing element 16. Assume the signal voltage output by the sensing element 16 is U. in If the amplification factor of the amplifier circuit is A, then the amplified signal voltage U amp =U in ×A, the amplified signal is easier to process later;

[0037] The filter circuit employs bandpass filtering technology, and its cutoff frequency can be set according to actual measurement requirements, such as setting a low-frequency cutoff frequency f. L and high-frequency cutoff frequency f H Only frequencies within f are allowed. L to f H Signals within the range (frequency components related to the acceleration signal) pass through, effectively removing high-frequency and low-frequency noise interference;

[0038] An analog-to-digital converter (ADC) is used to convert a filtered analog signal into a digital signal. Assume the voltage range of the analog signal is 0-U. max If the number of bits in the analog-to-digital converter is n, then the converted digital signal value D is: ;

[0039] Among them, U filter This is the filtered analog signal voltage, which facilitates subsequent processing and analysis.

[0040] In this embodiment, specifically: the shielding layer 14 is made of copper foil, and the shielding layer 14 is welded to the inner wall of the outer shell 13 to form a grounding loop; when the sensor is in an environment with electromagnetic interference, the electromagnetic interference signal will be blocked by the shielding layer 14, and at the same time, the interference signal will be guided to the ground through the grounding loop, so as to prevent the electromagnetic interference signal from entering the sensing element 16 and the circuit board 20, thereby ensuring the purity of the signal.

[0041] In this embodiment, specifically: a connector 25 is provided on the front part of the outer side wall of the outer casing 13, and the signal interaction between the sensor and the external device is realized through the connector 25;

[0042] The connector 25 is a shielded circular connector with four signal transmission pins inside, which are respectively connected to the digital signal output terminal, power input terminal, ground terminal of the signal processing circuit module 24 on the circuit board 20, and the status feedback terminal of the temperature compensation circuit module 23. The outer shell of the connector 25 is made of metal and is connected to the shielding layer 14 inside the outer shell 13 by wires to form a continuous electromagnetic shielding path. When the sensor is working, the processed and compensated acceleration digital signal is transmitted to the external microprocessor through the signal pins of the connector 25. At the same time, the external device provides DC power (such as 5V or 12V) to the sensor through the connector 25. The ground terminal, together with the base 11 and the shielding layer 14, forms a grounding network to further suppress the coupling of electromagnetic interference during signal transmission.

[0043] In this embodiment, specifically: a sealing gasket 26 is attached to the outer side of the upper surface of the base 11 near the external threaded connecting cylinder 12, and the top of the sealing gasket 26 is attached to the lower surface of the outer shell 13. The sealing gasket 26 ensures the airtightness of the connection between the outer shell 13 and the base 11, preventing external dust, moisture and other substances from entering the interior and affecting the operation of the components.

[0044] In this embodiment, specifically: mounting feet 27 are welded on both sides of the base 11, and mounting holes 28 are provided at the center of the upper surface of the mounting feet 27. The mounting holes 28 on the mounting feet 27 facilitate the fixing and installation of the sensor with bolts.

[0045] Working principle or structural principle: When in use, the sensor is fixed to the designated position of the device to be monitored by bolts through the mounting holes 28 on the mounting feet 27 on both sides of the base 11; after installation, the outer shell 13 is tightly connected to the base 11 through the external threaded connecting cylinder 12, and the shielding layer 14 on the inner sidewall of the two forms a complete electromagnetic shielding space.

[0046] When the device generates acceleration, the sensing element 16 (manufactured using MEMS technology) located in the space enclosed by the shielding layer 14 is subjected to acceleration, and the mass block inside it is displaced, thereby converting the acceleration change into a weak electrical signal; the weak electrical signal output by the sensing element 16 is transmitted to the signal processing circuit module 24 on the circuit board 20 through wires.

[0047] During the operation of the sensing element 16, the temperature sensor 22 fixed on the upper surface of the base 11 via the support frame 21 monitors the ambient temperature around the sensing element 16 in real time and transmits the temperature signal to the compensation circuit module 23 on the circuit board 20 through wires to eliminate the influence of temperature changes on the output signal of the sensing element 16 and ensure the accuracy of measurement under different temperature environments.

[0048] Meanwhile, the shielding layer 14, which is fixedly connected to the inner wall of the external threaded connecting cylinder 12 and the outer shell 13, will block electromagnetic interference signals in the surrounding environment and conduct the electromagnetic interference signals to the ground through the grounding circuit, thus ensuring the purity of the signal.

[0049] The digital signal, after being processed by the signal processing circuit module 24 and compensated by the compensation circuit module 23, is transmitted to an external microprocessor or display device through the connector 25 on the front of the outer wall of the housing 13 for subsequent analysis, recording and display, thereby realizing real-time and high-precision monitoring of the device acceleration.

[0050] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An interference-resistant acceleration sensor, characterized by Includes a main component (1), which includes a base (11), an external threaded connecting cylinder (12), a housing (13), a shielding layer (14), a mounting bracket (15), a sensing element (16), a plastic column (18), a screw (19), a circuit board (20), a support frame (21), and a temperature sensor (22). The outer side of the upper surface of the base (11) is welded with an external threaded connecting cylinder (12), and the outer side wall of the external threaded connecting cylinder (12) is threaded with a shell (13). The inner side walls of the external threaded connecting cylinder (12) and the shell (13) are both fixedly connected with a shielding layer (14). The center of the upper surface of the base (11) is fixedly connected with a sensing element (16) by a mounting bracket (15). The sensing element (16) is located in the space enclosed by the shielding layer (14). Two plastic pillars (18) are fixedly connected to the side of the upper surface of the base (11) near the mounting bracket (15). The top of the two plastic pillars (18) is fixedly connected with a circuit board (20) by screws (19). The other side of the upper surface of the base (11) near the mounting bracket (15) is fixedly connected with a temperature sensor (22) by a support frame (21).

2. The anti-interference acceleration sensor according to claim 1, wherein Multiple elastic pads (17) are fixedly connected to the outer side of the center of the upper surface of the base (11), and the tops of the multiple elastic pads (17) are attached to the bottom of the sensing element (16).

3. The anti-interference acceleration sensor according to claim 1, wherein The circuit board (20) has a compensation circuit module (23) on the front of its upper surface. The compensation circuit module (23) forms a circuit with the temperature sensor (22) and the sensing element (16) through wires.

4. The anti-interference acceleration sensor according to claim 1, wherein A signal processing circuit module (24) is provided in the middle of the upper surface of the circuit board (20), and the signal processing circuit module (24) is electrically connected to the sensing element (16).

5. The interference-resistant acceleration sensor according to claim 1, wherein The shielding layer (14) is made of copper foil. The shielding layer (14) is welded to the inner wall of the outer shell (13) to form a grounding circuit.

6. The anti-interference acceleration sensor according to claim 1, wherein A connector (25) is provided on the front part of the outer side wall of the outer casing (13).

7. The interference-resistant acceleration sensor according to claim 1, wherein A sealing gasket (26) is attached to the upper surface of the base (11) near the outer side of the external threaded connecting cylinder (12), and the top of the sealing gasket (26) is attached to the lower surface of the outer shell (13).

8. The anti-interference acceleration sensor according to claim 1, wherein The base (11) has mounting feet (27) welded on both sides, and mounting holes (28) are provided at the center of the upper surface of the mounting feet (27).

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