MEMS atmospheric electric field sensor and assembly method thereof

Abstract

The present invention provides a MEMS atmospheric electric field sensor and an assembly method thereof, and relates to the field of sensor technology. Among them, a first groove is formed at the bottom of a conductive shell toward the top thereof; a conductive component is placed inside the first groove; an insulating component is placed inside the first groove and fixed to the bottom of the conductive component; at least a portion of a middle cylinder component is placed inside the first groove and arranged at the bottom of the insulating component, wherein a first internal cavity is formed inside the middle cylinder component, and an adhesive is filled in the first internal cavity; a MEMS electric field measurement module is vertically clamped inside the first internal cavity and wrapped by an adhesive, wherein the MEMS electric field measurement module includes a wire connected thereto, and the top end of the wire sequentially passes through the middle cylinder component and the insulating component and then is connected to the conductive component. The present invention can reduce the volume of the MEMS atmospheric electric field sensor, enhance the fixing performance of the MEMS electric field measurement module, and improve the vibration and impact resistance of the MEMS electric field measurement module.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular to a MEMS atmospheric electric field sensor and an assembling method thereof. Background Art

[0002] Lightning disaster is one of the ten major natural disasters announced by the United Nations. Lightning is also an important weather factor that directly affects the success or failure of space launches. In the spacecraft launch specifications, the atmospheric electric field strength has been listed as one of the main conditions for whether a spacecraft can be launched. Lightning strikes can cause serious damage to the power grid, including line tripping, power transmission and transformation equipment failure, and unplanned line shutdowns, which directly affect the safe and stable operation of the power grid and the safety and reliability of power supply. In addition to using a large number of electrical and electronic equipment and auxiliary facilities that are very sensitive to lightning, the petrochemical industry also uses a large part of the materials and finished product storage and transportation in the production process, which are flammable and explosive. It is one of the sensitive industries with frequent lightning disasters. At present, MEMS atmospheric electric field sensors are mostly used to monitor and analyze changes in the intensity and polarity of the atmospheric electric field, identify changes in the atmospheric electric field that may cause lightning strikes, and issue early warnings before the disaster comes. This is of great significance to lightning protection and disaster reduction, and is also the development trend of future meteorological departments in forecasting disastrous weather such as lightning.

[0003] like Figure 1 As shown, in the invention patent with the publication (announcement) number CN107300642B, a MEMS ground atmospheric electric field sensor is disclosed, which includes a conductive shell 1', a cavity structure 2' and a MEMS electric field measurement module 3', wherein the MEMS electric field measurement module 3' is located inside the cavity structure 2', and the MEMS electric field measurement module 3' is connected to the conductive shell 1' through a wire, thereby receiving the charge transmitted by the conductive shell 1' to measure the size of the external DC electric field. However, since the cavity structure 2' is located below the conductive shell 1', the volume of the MEMS ground atmospheric electric field sensor is relatively large. In addition, since the MEMS electric field measurement module 3' is only fixed inside the cavity structure 2' by a fixed column, the MEMS electric field measurement module 3' has poor vibration and impact resistance inside the cavity structure 2'.

[0004] Therefore, how to reduce the volume of the MEMS ground atmospheric electric field sensor and enhance the vibration and shock resistance of the MEMS electric field measurement module are technical problems that need to be solved urgently. Summary of the invention

[0005] In view of the shortcomings existing in the above problems, the present invention provides a MEMS atmospheric electric field sensor and an assembly method thereof which can reduce the volume of the existing MEMS ground atmospheric electric field sensor and improve the vibration and impact resistance of the MEMS electric field measurement module.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a MEMS atmospheric electric field sensor, comprising:

[0007] A conductive shell having a first groove formed on its bottom end surface toward its top;

[0008] A conductive component is disposed inside the first groove;

[0009] An insulating component, disposed inside the first groove and fixed to the bottom of the conductive component;

[0010] a middle cylinder component, at least a portion of which is disposed inside the first groove and arranged at the bottom of the insulating component, wherein a first internal cavity is formed inside the middle cylinder component and the first internal cavity is filled with an adhesive;

[0011] The MEMS electric field measurement module is vertically clamped inside the first internal cavity and wrapped by the adhesive, wherein the MEMS electric field measurement module includes a wire connected thereto, the top end of the wire sequentially passes through the middle cylinder component and the insulating component and then is connected to the conductive component, so as to detect the external electric field through the conductive component and the conductive shell.

[0012] In one embodiment, a step portion is provided in the first groove, and the step portion divides the first groove into a first area and a second area, wherein the outer diameter of the conductive component is the same as the inner diameter of the first area and is movably connected to the first area, and the second area surrounds the outside of the first internal cavity, and the inner wall surface of the second area and at least a portion of the outer wall surface of the middle tube component form a spacing area.

[0013] In one embodiment, the conductive component includes a base plate, an annular side wall connected to the base plate, and an upper cover connected to the annular side wall, the base plate, the annular side wall and the upper cover form a second internal cavity, wherein the annular side wall is movably connected to the first area, and a first through hole and a conductive fixing position connected to the wire are opened on the base plate.

[0014] In one embodiment, the insulating component includes a base, a boss extending upward from the top end surface of the base, and a second through hole passing through the base and the boss in sequence, wherein the boss is placed inside the first through hole, and at least a portion of the second through hole is placed inside the first through hole.

[0015] In one embodiment, the middle tube component includes:

[0016] a middle cylinder, which is placed inside the second region and connected to the bottom of the insulating component, wherein a second groove is formed on the bottom end surface of the middle cylinder toward the top thereof, wherein a third through hole and an annular column are provided on the top end surface of the middle cylinder, and the annular column surrounds the outside of the third through hole, and when the annular column is placed inside the second through hole, the inside of the first internal cavity is communicated with the inside of the second internal cavity at least through the third through hole, the annular column, the second through hole, and the inside of the second internal cavity;

[0017] A bottom cover, at least a portion of which is disposed inside the first groove, wherein the bottom cover is disposed at the bottom end of the middle tube and closes the bottom opening of the second groove to form the first internal cavity.

[0018] In one embodiment, the top end of the wire at least extends through the third through hole, the annular column, and the second through hole to the inside of the second internal cavity, and is connected to the conductive fixing position through a conductive component.

[0019] In one of the embodiments, the top end surface formed by the adhesive after solidification is not higher than the top end surface of the annular column.

[0020] In one embodiment, the top of the MEMS electric field measurement module abuts against the inner wall surface of the top of the middle tube, and the end of the MEMS electric field measurement module is connected to a connector provided on the bottom cover.

[0021] In a second aspect, the present invention further provides a method for assembling a MEMS atmospheric electric field sensor, which is used to assemble the above-mentioned MEMS atmospheric electric field sensor, comprising the following steps:

[0022] Placing the MEMS electric field measurement module in the first internal cavity so that the top end of the wire connected to the MEMS electric field measurement module extends to the outside of the middle cylinder component;

[0023] Filling the first internal cavity with the adhesive so that the adhesive wraps around the outside of the MEMS electric field measurement module;

[0024] After the insulating component is connected to the conductive component, it is fixed on the top end surface of the middle cylinder component;

[0025] The top end of the wire passes through the insulating component and is connected to the conductive component, so that the MEMS electric field measurement module is connected to the conductive component through the wire;

[0026] The conductive component is connected to the inner wall of the conductive shell, so that the conductive shell at least covers the outer side of the middle cylinder component, and at the same time, the MEMS electric field measurement module is connected to the conductive shell through the wire.

[0027] In one embodiment, the middle cylinder component includes a middle cylinder and a bottom cover, and a third through hole and an annular column are provided on the top end face of the middle cylinder, wherein the adhesive needs to be injected into the interior of the first internal cavity through the third through hole after the middle cylinder and the bottom cover are connected to wrap the MEMS electric field measurement module in the first internal cavity.

[0028] In one of the embodiments, the top end surface formed after the adhesive is injected is higher than the top end surface of the third through hole, and is not higher than the top end surface of the annular column.

[0029] Compared with the prior art, the present invention has one of the following advantages:

[0030] By arranging the MEMS electric field measurement module inside the conductive housing, the volume of the MEMS atmospheric electric field sensor can be reduced compared to the prior art, and the distance between the MEMS electric field measurement module and the conductive component through the conductor can be shortened;

[0031] The MEMS electric field measurement module is vertically clamped inside the first internal cavity and wrapped by an adhesive, which can not only enhance the fixing performance of the MEMS electric field measurement module, but also improve the vibration resistance, shock resistance and reliability of the MEMS electric field measurement module;

[0032] The conductive components are all embedded in the first area, which can enhance the connection performance between the conductive components and the conductive shell and prevent the conductive shell from shaking. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a structural diagram of an existing MEMS ground atmospheric electric field sensor;

[0034] Figure 2 It is a three-dimensional diagram of the MEMS atmospheric electric field sensor in the first embodiment of the present invention;

[0035] Figure 3 for Figure 2 A cross-sectional view of

[0036] Figure 4 for Figure 3 A magnified view of part A;

[0037] Figure 5 for Figure 2 A cross-sectional view of the conductive housing;

[0038] Figure 6 for Figure 2 Exploded view of the conductive parts;

[0039] Figure 7 for Figure 2 Structural diagram of the MEMS electric field measurement module connected to the connector and the conductive component respectively.

[0040] The main reference numerals are as follows:

[0041] 1`-conductive shell; 2`-cavity structure; 3`-MEMS electric field measurement module;

[0042] 1-conductive housing; 100-first area; 101-second area; 102-third area; 2-conductive component;

[0043] 200-bottom plate; 2001-conductive fixing position; 2002-first through hole; 201-annular side wall; 202-upper cover; 203-second internal cavity; 204-conductive component; 3-insulating component; 300-base; 301-convex column; 302-second through hole; 4-middle cylinder; 400-first internal cavity; 401-third through hole; 402-annular column; 5-bottom cover; 500-connector; 6-MEMS electric field measurement module; 600-MEMS electric field sensitive chip; 601-preamplifier circuit board; 6010-fourth through hole; 602-drive demodulation circuit board; 603-insulating sealing box; 604-wire. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. 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.

[0045] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "top surface", "bottom surface", "inside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0046] Embodiment 1

[0047] like Figures 2 to 7 As shown, this embodiment provides a MEMS atmospheric electric field sensor, including:

[0048] The conductive housing 1 has a first groove formed on its bottom end surface toward its top;

[0049] A conductive component 2 is disposed inside the first groove;

[0050] The insulating component 3 is placed inside the first groove and fixed to the bottom of the conductive component 2;

[0051] A middle cylinder component, at least a portion of which is disposed inside the first groove and is arranged at the bottom of the insulating component 3, wherein a first internal cavity 400 is formed inside the middle cylinder component, and the first internal cavity 400 is filled with an adhesive;

[0052] The MEMS electric field measurement module 6 is vertically clamped inside the first internal cavity 400 and wrapped with an adhesive, wherein the MEMS electric field measurement module 6 includes a wire 604 connected thereto, and the top end of the wire 604 sequentially passes through the middle cylinder component and the insulating component 3 and is connected to the conductive component 2 to detect the external electric field through the conductive component 2 and the conductive shell 1.

[0053] In this embodiment, by setting the MEMS electric field measurement module 6 inside the conductive shell 1, the volume of the MEMS atmospheric electric field sensor can be reduced compared with the prior art; in addition, the MEMS electric field measurement module 6 is vertically clamped inside the first internal cavity 400 and wrapped with an adhesive, which can not only enhance the fixing performance of the MEMS electric field measurement module 6, but also improve the vibration resistance, impact resistance and reliability of the MEMS electric field measurement module.

[0054] In this embodiment, the conductive shell 1, the conductive component 2 and the middle cylinder component are all conductive and can be made of metal, or the inner or outer surface of an insulating material or the inner and outer surfaces are electroplated with metal. The insulating component 3 can be made of inorganic insulating material, organic insulating material or mixed insulating material.

[0055] The shape of the conductive shell 1 is roughly similar to a columnar structure, and the shape of its transverse cross section can be cylindrical, rectangular, square or other regular or irregular polygonal shapes.

[0056] In the above embodiment, specifically, the shape of the conductive housing 1 is roughly similar to a cylindrical structure, the top of which is arc-shaped, and a first groove extending toward the top is formed on the bottom end surface thereof.

[0057] Furthermore, an annular step portion is provided in the first groove, which divides the first groove into a first area 100 and a second area 101, wherein the diameter of the first area 100 is smaller than the diameter of the second area 101, the position of the first area 100 is closer to the top of the conductive shell 1 relative to the second area 101, and the position of the second area 101 is closer to the bottom of the conductive shell 1 relative to the first area 100.

[0058] In this embodiment, further, in the conductive housing 1, a third area 102 is provided below the second area 101, and its position is closer to the bottom of the conductive housing 1 than the second area 101. The third area 102 is substantially a trumpet-shaped structure.

[0059] In this embodiment, the conductive shell 1 is made of metal conductive material, which is easy to detect and sense the electric charges in the atmosphere.

[0060] In this embodiment, the conductive component 2 is a cylindrical structure. The outer diameter of the conductive component 2 is the same as the inner diameter of the first region 100, and the conductive component 2 can be completely embedded in the first region 100 by adopting a movable connection method.

[0061] Optionally, the movable connection method can be a threaded connection method, a snap connection method, a key connection method, etc.

[0062] Preferably, the conductive component 2 is placed in the first area 100 by means of threaded connection, or is separated from the first area 100 .

[0063] A first thread structure is formed on the outer wall surface of the conductive component 2 , and a second thread structure matching the first thread structure is formed on the inner wall surface of the first region 100 .

[0064] In this embodiment, specifically, the conductive component 2 includes a base plate 200, an annular side wall 201 connected to the base plate 200, and an upper cover 202 connected to the annular side wall 201, the base plate 200, the annular side wall 201 and the upper cover 202 form a second internal cavity 203, wherein the annular side wall 201 is movably connected to the first area 100, and a first through hole 2002 and a conductive fixing position 2001 connected to the wire 604 are opened on the base plate 200.

[0065] The first thread structure is formed on the outer wall surface of the annular side wall 201 , and cooperates with the second thread structure arranged on the inner wall surface of the first area 100 to place the conductive component 2 inside the first area 100 .

[0066] Optionally, the annular side wall 201 and the base plate 200 are an integral structure or a split structure, the first through hole 2002 can be an axial hole coaxially arranged with the base plate 200, or an eccentric hole coaxially arranged with the base plate 200, and the base plate 200 is also provided with a plurality of assembly holes surrounding the outside of the first through hole 2002, as well as a conductive fixing position 2001 connected to the wire 604 through a conductive component 204.

[0067] Preferably, the first through hole 2002 is an axial hole coaxially arranged on the bottom plate 200, and the annular side wall 201 and the bottom plate 200 are an integrated structure, which can ensure the connection performance between the two compared to the split structure, and ensure that the external charge detected by the conductive shell 1 can be transmitted to the bottom plate 200 through the first area 100 and the annular side wall 201, and the charge is input into the conductive component 204 through the conductive fixing position 2001.

[0068] Furthermore, the position of the conductive fixing position 2001 is closer to the first through hole 2002 than the positions of the assembly holes. This design facilitates the connection between the wire 604 and the conductive fixing position 2001 .

[0069] In this embodiment, optionally, the conductive component 204 is a screw, or is composed of a screw and a connecting plate connected thereto, and the conductive fixing position 2001 is an assembly groove opened on the base plate 200 and matched with the screw, and a thread matching with the screw is formed on the inner wall surface of the assembly groove.

[0070] When the conductive component 204 is a screw, the top of the wire 604 is wound around the outside of the screw. When the screw is fastened inside the assembly slot, the wire 604 is connected to the assembly slot through the screw to input the charge into the wire 604.

[0071] When the conductive component 204 is a screw and a connecting piece sleeved on the outside of the screw and connected to the screw, the top of the wire 604 is welded to the connecting piece. When the screw is fastened inside the assembly slot, the wire 604 is connected to the assembly slot through the connecting piece and the screw to input the charge into the wire 604.

[0072] In this embodiment, further, a first thread is formed on the inner wall surface of the annular side wall 201, and a second thread is formed on the outer wall surface of the upper cover 202, and the first thread cooperates with the second thread to assemble the upper cover 202 on the annular side wall 201. When the upper cover 202 is connected to the annular side wall 201, a second internal cavity 203 is formed inside the conductive component 2.

[0073] After the wire 604 is connected to the conductive component 204 , the connection point is adjacent to the bottom of the second internal cavity 203 . When the upper cover 202 is connected to the annular side wall 201 , the connection point can be shielded to protect the connection point.

[0074] In this embodiment, since the outer diameter of the conductive component 2 is the same as the inner diameter of the first region 100, and the conductive component 2 is placed inside the first region 100, not only the contact area with the conductive shell 1 is enhanced to ensure the charge transmission effect, but also the connection performance between the conductive component 2 and the conductive shell 1 is improved to prevent the conductive shell 1 from shaking. In addition, after the conductive component 2 is connected to the conductive shell 1, the conductive shell 1 can gather the external charges detected and sensed by it into the conductive component 2 to enhance the charge strength and improve the accuracy of detecting external charges.

[0075] In this embodiment, the insulating component 3 is a cylindrical structure, which is made of polytetrafluoroethylene and is fixed to the bottom of the conductive component 2 by screws. The insulating component 3 is coaxially arranged with the conductive component 2, and its diameter and thickness are substantially the same as those of the conductive component 2.

[0076] Specifically, the insulating component 3 includes a base 300, a boss 301 extending upward from the top end surface of the base 300, and a second through hole 302 that passes through the base 300 and the boss 301 in sequence, wherein the boss 301 is placed inside the first through hole 2002, and at least a portion of the second through hole 302 is placed inside the first through hole 2002.

[0077] When the boss 301 is placed inside the first through hole 2002, since the second through hole 302 is coaxially arranged with the first through hole 2002, the top end of the wire 604 extends along the axial direction of the second through hole 302 into the second internal cavity 203, and is connected to the conductive fixing position 2001 through the conductive component 204, which can shorten the distance that the wire 604 extends into the second internal cavity 203.

[0078] In addition, the protrusion 301 is provided to facilitate the positioning and assembly of the conductive component 2 and the insulating component 3. At the same time, when the protrusion 301 is placed inside the first through hole 2002, the overall thickness of the conductive component 2 and the insulating component 3 after assembly can also be reduced.

[0079] In this embodiment, by providing the insulating component 3, the conductive housing 1 and the conductive component 2 form an isolated conductor, and the charge received by the conductive component 2 can only be transmitted through the wire 604, thereby ensuring the transmission path of the charge.

[0080] In this embodiment, the middle cylinder component is in the shape of a cylindrical structure, and the middle cylinder component and the insulating component 3 are coaxially arranged.

[0081] Specifically, the middle cylinder component includes a middle cylinder 4 and a bottom cover 5 assembled on the bottom end surface of the middle cylinder 4. The middle cylinder 4 is placed inside the second area 101, has an outer diameter the same as that of the insulating component 3, and is fixed to the bottom of the insulating component 3 by screws.

[0082] Furthermore, a third through hole 401 and an annular column 402 coaxially arranged with the middle cylinder 4 are provided on the top end surface of the middle cylinder 4 , and the annular column 402 surrounds the outer side of the third through hole 401 .

[0083] When the middle cylinder 4 is fixed to the bottom of the insulating component 3, the annular column 402 is placed inside the second through hole 302, and the third through hole 401 is connected to the second internal cavity 203 through the annular column 402 and the second through hole 302. Since the third through hole 401, the annular column 402 and the second through hole 302 are coaxially arranged, the top end of the wire 604 can extend to the inside of the second internal cavity 203 along the axial direction through the third through hole 401, the annular column 402 and the second through hole 302, and is connected to the conductive fixing position 2001 through the conductive component 204. At the same time, when the annular column 402 is placed inside the second through hole 302, it is also convenient to position and assemble the middle cylinder 4 and the insulating component 3.

[0084] Furthermore, a second groove extending toward the top is formed on the bottom end surface of the middle cylinder 4, and the bottom cover 5 is arranged at the bottom end of the middle cylinder 4 and closes the bottom opening of the second groove to form a first internal cavity 400 for placing the MEMS electric field measurement module 6.

[0085] The second area 101 surrounds the outside of the first internal cavity 400, and a spacing area is formed between the inner wall of the second area 101 and the outer wall of the middle cylinder 4, through which the conductive shell 1 can be prevented from contacting the outer wall of the middle cylinder 4, thereby shielding the measured electric field.

[0086] Furthermore, a portion of the bottom cover 5 is placed in the third area 102. The wall surface of the third area 102 extends obliquely downward from the wall surface of the second area 101 to form a trumpet-shaped structure, which can prevent the conductive housing 1 and the bottom cover 5 from being connected by rainwater when it rains, thereby shielding the measured electric field.

[0087] Furthermore, the first internal cavity 400 is filled with adhesive, wherein the adhesive needs to be injected into the first internal cavity 400 through the third through hole 401 after the middle tube 4 is connected to the bottom cover 5 to wrap the MEMS electric field measurement module 6 in the first internal cavity 400.

[0088] After the adhesive is injected, the end surface of the adhesive should be higher than the top end surface of the third through hole 401 to ensure that the first internal cavity 400 is filled with the adhesive so as to wrap around the outside of the MEMS electric field measurement module 6 .

[0089] Preferably, the top end surface formed after the adhesive is injected should be higher than the third through hole 401, and not higher than the top end surface of the annular column 402. This design can not only ensure that the adhesive can be wrapped around the outside of the MEMS electric field measurement module 6, but also prevent the adhesive from entering the second through hole 302, thereby preventing the adhesive from affecting the separation of the middle cylinder 4 and the insulating component 3 after solidification.

[0090] Optionally, the adhesive may be a resin or a structural adhesive, etc. The adhesive is not limited here and may be selected according to actual needs.

[0091] In this embodiment, the middle cylinder 4 for placing the MEMS electric field measurement module 6 is placed inside the conductive housing 1, which can reduce the volume of the MEMS atmospheric electric field sensor compared to the prior art. In addition, the MEMS electric field measurement module 6 is vertically clamped inside the first internal cavity 400 and wrapped with an adhesive, which can not only enhance the fixing performance of the MEMS electric field measurement module 6, but also improve the vibration resistance, impact resistance and reliability of the MEMS electric field measurement module.

[0092] In addition, in this embodiment, the insulating component 3 is located between the conductive component 2 and the middle tube 4, so that the wire 604 must pass through the second through hole 302 in the insulating component 3 before extending into the second internal cavity 203, and is connected to the conductive fixing position 2001 through the conductive component 204, which can prevent the wire 604 from contacting the external charge detected by the conductive shell 1 during the extension process.

[0093] In this embodiment, the MEMS electric field measurement module 6 is vertically clamped inside the first internal cavity 400, wherein the top of the MEMS electric field measurement module 6 abuts against the inner wall of the top of the middle tube 4, and the end of the MEMS electric field measurement module 6 is connected to the connector 500 provided on the bottom cover 5.

[0094] One or more MEMS electric field measurement modules 6 can be installed in the first internal cavity 400 .

[0095] Specifically, only one MEMS electric field measurement module 6 is arranged in the first internal cavity 400, which includes a MEMS electric field sensitive chip 600, a preamplifier circuit board 601 and a drive demodulation circuit board 602, and its shape can be circular, elliptical, rectangular, square or polygonal, etc. The shielding electrode in the MEMS electric field sensitive chip 600 periodically vibrates to modulate the detection electrode to generate a detection current, and the MEMS electric field sensitive chip 600 is placed in an insulating sealing box 603, which is made of insulating material and has a metal cover on the top; the preamplifier circuit board 601 realizes the conversion of the electric field current signal into a voltage signal; the drive demodulation circuit board 602 generates the dual-path differential signal required for the normal operation of the MEMS electric field sensitive chip 600 and realizes the resolution of the electric field information of the voltage signal output by the preamplifier circuit board 601.

[0096] The end of the wire 604 can be connected to the MEMS electric field sensitive chip 600 or the metal cover plate located on the top of the insulating sealing box 603, wherein the wire 604 can be a common wire, a shielded wire, a high-frequency radio frequency wire, a semi-steel semi-flexible radio frequency wire, etc.

[0097] Since the MEMS electric field measurement module 6 is vertically arranged in the first internal cavity 400, in order to shorten the extension distance of the wire 604 to the third through hole 401, the position of the third through hole 401 is toward the area between the preamplifier circuit board 601 and the driver demodulation circuit board 602. In addition, since the top of the preamplifier circuit board 601 and the top of the driver demodulation circuit board 602 are both in contact with the inner side of the top end surface of the first internal cavity 400, a fourth through hole 6010 is opened in the area without circuit elements in the preamplifier circuit board 601, and the wire 604 extends to the position of the third through hole 401 after passing through the fourth through hole 6010, and extends upward along the axial direction of the third through hole 401 to the second internal cavity 203, so as to be connected to the conductive fixing position 2001 through the conductive component 204, thereby inputting the charge into the MEMS electric field measurement module 6 to measure the external DC electric field.

[0098] In addition, in this embodiment, since the outer diameter of the conductive component 2 is the same as the inner diameter of the first region 100, the conductive component 2 can be embedded in the first region 100, thereby improving the connection performance between the conductive component 2 and the conductive housing 1. Under this condition, in order not to affect the electrical isolation performance between the conductive component 2 and the middle cylinder 4, the insulating component 3 is set between the conductive component 2 and the middle cylinder 4.

[0099] In this embodiment, the working principle of the MEMS atmospheric electric field sensor is as follows: since the conductive shell 1 is electrically connected to the MEMS electric field measurement module 6 through the wire 604, when there is a DC electric field E in the outside world, the conductive shell 1 and the metal cover generate detection charges, which are linearly related to the DC electric field E. The detection charges of the metal cover generate an electric field Eg, and Eg is linearly related to the DC electric field E. The MEMS electric field sensitive chip 600 indirectly measures the size of the external DC electric field E by measuring the electric field Eg.

[0100] Embodiment 2

[0101] This embodiment provides a method for assembling a MEMS atmospheric electric field sensor, which is used to assemble the MEMS atmospheric electric field sensor in the first embodiment, and includes the following steps:

[0102] S1, placing a MEMS electric field measurement module in the first internal cavity, so that the top end of the wire connected to the MEMS electric field measurement module extends to the outside of the middle cylinder component;

[0103] S2, filling the first internal cavity with adhesive so that the adhesive wraps around the outside of the MEMS electric field measurement module;

[0104] S3, after connecting the insulating component and the conductive component, fix them on the top end surface of the middle cylinder component;

[0105] S4, the top end of the wire passes through the insulating component and is connected to the conductive component, so that the MEMS electric field measurement module is connected to the conductive component through the wire;

[0106] S5. Connect the conductive component to the inner wall of the conductive shell so that the conductive shell at least covers the outer side of the middle cylinder component. Meanwhile, connect the MEMS electric field measurement module to the conductive shell through a wire.

[0107] In this embodiment, further, in step S2, the middle cylinder component includes a middle cylinder and a bottom cover, and a third through hole and an annular column are provided on the top end face of the middle cylinder, wherein the adhesive needs to be injected into the interior of the first internal cavity through the third through hole after the middle cylinder and the bottom cover are connected to wrap the MEMS electric field measurement module in the first internal cavity.

[0108] When injecting the adhesive, the end surface after the adhesive is injected should be higher than the top end surface of the third through hole to ensure that the first internal cavity is filled with the adhesive so as to be wrapped around the outside of the MEMS electric field measurement module.

[0109] Preferably, the top end surface formed after the adhesive is injected should be higher than the third through hole and not higher than the top end surface of the annular column. This design can not only ensure that the adhesive can be wrapped around the outside of the MEMS electric field measurement module, but also prevent the adhesive from entering the second through hole, preventing the adhesive from solidifying and affecting the separation of the middle cylinder and the insulating component.

[0110] In this embodiment, through the above-mentioned assembly method, the MEMS electric field measurement module can be connected to the conductive shell through a wire. When there is a DC electric field E in the outside world, the conductive shell and the metal cover generate detection charges, which are linearly related to the DC electric field E. The detection charges of the metal cover generate an electric field Eg, and Eg is linearly related to the DC electric field E. The MEMS electric field sensitive chip indirectly measures the size of the external DC electric field E by measuring the electric field Eg.

[0111] In addition, the MEMS atmospheric electric field sensor in the embodiment of the present invention can not only measure the external electric field, but also be applied to lightning warning, industrial static electricity measurement, power grid DC electric field measurement and related static electricity field measurement devices.

[0112] The above description is only a preferred embodiment of the present invention, which is only illustrative and not restrictive of the present invention. Those skilled in the art understand that many changes, modifications, and even equivalences may be made to the present invention within the spirit and scope defined by the claims of the present invention, but all of them will fall within the scope of protection of the present invention.

Claims

1. A MEMS atmospheric electric field sensor, characterized in that: include: A conductive shell having a first groove formed on its bottom end surface toward its top; A conductive component is disposed inside the first groove; An insulating component, disposed inside the first groove and fixed to the bottom of the conductive component; a middle cylinder component, at least a portion of which is disposed inside the first groove and arranged at the bottom of the insulating component, wherein a first internal cavity is formed inside the middle cylinder component and the first internal cavity is filled with an adhesive; A MEMS electric field measurement module is vertically clamped inside the first internal cavity and wrapped by the adhesive, wherein the MEMS electric field measurement module includes a wire connected thereto, the top end of the wire sequentially passes through the middle cylinder component and the insulating component and then is connected to the conductive component, so as to detect an external electric field through the conductive component and the conductive housing; A step portion is provided in the first groove, and the step portion divides the first groove into a first area and a second area; The conductive component includes a bottom plate, an annular side wall connected to the bottom plate, and an upper cover connected to the annular side wall, wherein the bottom plate, the annular side wall and the upper cover form a second internal cavity, wherein the annular side wall is movably connected to the first area, and a first through hole and a conductive fixing position connected to the wire through a conductive component are provided on the bottom plate; The conductive component is a screw and a connecting piece sleeved on the outside of the screw and connected to the screw. The top of the wire is welded to the connecting piece. When the screw is fastened inside the assembly groove, the wire is connected to the assembly groove through the connecting piece and the screw to input the charge into the wire. The insulating component is fixed to the bottom of the conductive component by screws, the insulating component is coaxially arranged with the conductive component, the diameter and thickness of the insulating component are substantially the same as those of the conductive component, the insulating component comprises a base, a boss extending upward from the top end surface of the base, and a second through hole sequentially penetrating the base and the boss, wherein the boss is disposed inside the first through hole, and at least a portion of the second through hole is disposed inside the first through hole; The middle cylinder component includes a middle cylinder and a bottom cover. The outer diameter of the middle cylinder is the same as the outer diameter of the insulating component and is fixed to the bottom of the insulating component by screws. A third through hole and an annular column coaxially arranged with the middle cylinder are provided on the top end surface of the middle cylinder. When the middle cylinder is fixed to the bottom of the insulating component, the annular column is placed inside the second through hole.

2. The MEMS atmospheric electric field sensor according to claim 1, characterized in that: The outer diameter of the conductive component is the same as the inner diameter of the first region and is movably connected to the first region. The second region surrounds the outside of the first internal cavity, and the inner wall of the second region and at least a portion of the outer wall of the middle tube component form a spacing area.

3. The MEMS atmospheric electric field sensor according to claim 2, characterized in that: The middle cylinder is placed inside the second region and connected to the bottom of the insulating component, and a second groove is formed on the bottom end surface of the middle cylinder toward the top thereof, wherein the annular column surrounds the outside of the third through hole, and when the annular column is placed inside the second through hole, the inside of the first internal cavity is communicated with the inside of the second internal cavity at least through the third through hole, the annular column, the second through hole, and the inside of the second internal cavity; At least a portion of the bottom cover is placed inside the first groove, wherein the bottom cover is arranged at the bottom end of the middle tube and closes the bottom opening of the second groove to form the first internal cavity.

4. The MEMS atmospheric electric field sensor according to claim 3, characterized in that: The top end of the wire at least extends to the inside of the second internal cavity through the third through hole, the annular column, and the second through hole, and is connected to the conductive fixing position through a conductive component.

5. The MEMS atmospheric electric field sensor according to claim 3 or 4, characterized in that: The top end surface formed after the adhesive is solidified is not higher than the top end surface of the annular column.

6. The MEMS atmospheric electric field sensor according to claim 5, characterized in that: The top end of the MEMS electric field measurement module abuts against the inner wall surface of the top end of the middle tube, and the end of the MEMS electric field measurement module is connected to a connector arranged on the bottom cover.

7. A method for assembling a MEMS atmospheric electric field sensor, used for assembling the MEMS atmospheric electric field sensor according to any one of claims 1 to 6, characterized in that: The following steps are involved: Placing the MEMS electric field measurement module in the first internal cavity so that the top end of the wire connected to the MEMS electric field measurement module extends to the outside of the middle cylinder component; Filling the first internal cavity with the adhesive so that the adhesive wraps around the outside of the MEMS electric field measurement module; After the insulating component is connected to the conductive component, it is fixed on the top end surface of the middle cylinder component; The top end of the wire passes through the insulating component and is connected to the conductive component, so that the MEMS electric field measurement module is connected to the conductive component through the wire; The conductive component is connected to the inner wall of the conductive shell, so that the conductive shell at least covers the outer side of the middle cylinder component, and at the same time, the MEMS electric field measurement module is connected to the conductive shell through the wire.

8. The assembly method according to claim 7, characterized in that: The middle cylinder component includes a middle cylinder and a bottom cover, and a third through hole and an annular column are provided on the top end face of the middle cylinder, wherein the adhesive needs to be injected into the interior of the first internal cavity through the third through hole after the middle cylinder and the bottom cover are connected to wrap the MEMS electric field measurement module in the first internal cavity.

9. The assembly method according to claim 8, characterized in that: The top end surface formed after the adhesive is injected is higher than the top end surface of the third through hole, and is not higher than the top end surface of the annular column.

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