Accelerometer

Abstract

Provided in the present invention is an accelerometer, comprising an outer coupling structure, a measurement structure connected to the outer coupling structure, and an inner coupling structure. The measurement structure comprises anchor points connected to the outer coupling structure, two seesaw structures elastically connected to the anchor points, and a displacement measurement assembly. The two seesaw structures are arranged opposite to each other. The outer coupling structure comprises an outer coupling structure inner ring that forms coupling connection separately with the outer sides of the two seesaw structures, and an outer coupling structure outer ring that surrounds the outer circumference of the outer coupling structure inner ring. The accelerometer is characterized by further comprising measurement electrode plates, the measurement electrode plates being fixed on the side of the inner coupling structure close to the outer coupling structure. The anchor points are evenly distributed at the central position of the outer coupling structure, the inner coupling structure being distributed around the anchor points. Compared with the related art, the accelerometer of the present invention can reduce fabrication error and improve structural robustness.

Description

Accelerometer TECHNICAL FIELD

[0001] The present application relates to the technical field of micro-mechanical structure, and particularly relates to an accelerometer. BACKGROUND

[0002] The accelerometer is a sensor for measuring acceleration, a basic physical quantity, and generally comprises mechanical acceleration sensing and displacement measurement. The commonly used mechanical acceleration sensing is to drive a torsional spring to rotate around a rotating shaft by an asymmetric proof mass along the rotating shaft under the action of acceleration, so that the corresponding capacitor plate region of the structure generates out-of-plane displacement, a differential capacitor is formed by placing a capacitor plate above or below the corresponding capacitor plate region of the structure, and the acceleration change can be obtained by detecting the change of the capacitor. TECHNICAL PROBLEM

[0003] In the related art, the accelerometer comprises a base and a detection structure connected to the base, the detection structure comprises an anchor point fixed to the base, a seesaw structure elastically connected to the anchor point, an inner side coupling structure coupled to the inner side of the seesaw structure, an outer side coupling structure coupled to the outer side of the seesaw structure, and a displacement detection assembly arranged on the outer side coupling structure and the inner side coupling structure, the two seesaw structures are oppositely arranged, the outer side coupling structure comprises an inner ring of the outer side coupling structure coupled to the outer sides of the two seesaw structures and an outer ring of the outer side coupling structure surrounding the outer side of the inner ring of the outer side coupling structure, and the anchor points are dispersed on the inner ring of the outer side coupling structure.

[0004] However, the anchor points are distributed on the outer side coupling structure, so that the anchor points of the overall structure are relatively dispersed, the whole structure is greatly affected by stress during processing, the base is easily deformed, and the robustness is low.

[0005] Therefore, it is necessary to provide a new accelerometer to solve the above technical problems. TECHNICAL SOLUTION

[0006] The purpose of the present application is to provide an accelerometer which places the anchor points on the middle position of the whole structure, so that the structure is less affected by stress during processing, the process error is smaller, and the structure obtains higher robustness.

[0007] In order to achieve the above object, the embodiment of the present application provides an accelerometer, which comprises an outer coupling structure, a detection structure connected to the outer coupling structure, and an inner coupling structure, the detection structure comprises anchor points connected to the outer coupling structure, two seesaw structures elastically connected to the anchor points, and a displacement detection assembly arranged on the outer coupling structure and the inner coupling structure; the inner sides of the two seesaw structures are coupled to the inner coupling structure, and the outer sides of the two seesaw structures are coupled to the outer coupling structure; the two seesaw structures are oppositely arranged, the outer coupling structure comprises an outer coupling structure inner ring coupled to the outer sides of the two seesaw structures respectively, and an outer coupling structure outer ring surrounding the outer periphery of the outer coupling structure inner ring; characterized in that the accelerometer further comprises a detection electrode plate fixed to one side of the inner coupling structure close to the outer coupling structure; the anchor points are uniformly distributed at the central position of the outer coupling structure, and the inner coupling structure is distributed around the anchor points.

[0008] The detection structure further comprises a first elastic member connecting the outer coupling structure inner ring and the corresponding seesaw structure, a second elastic member connecting the outer coupling structure inner ring and the outer coupling structure outer ring, and a third elastic member connecting the detection electrode plate and the corresponding seesaw structure.

[0009] Preferably, the anchor points comprise four anchor points, which are uniformly distributed at the geometric center of the outer coupling structure.

[0010] Preferably, the outer coupling structure inner ring and the inner coupling structure are alternately arranged with a plurality of positive and negative capacitor electrode plates.

[0011] Preferably, the inner coupling structure has a plurality of connecting beams, and the inner coupling structure is connected to the two seesaw structures through the connecting beams respectively.

[0012] Preferably, the length direction of the outer coupling structure is defined as the X-axis direction, the width direction of the outer coupling structure is defined as the Y-axis direction, and the thickness direction of the outer coupling structure is defined as the Z-axis direction; the two seesaw structures are symmetrically arranged on the outer coupling structure about the Y-axis; the displacement detection assembly comprises a plurality of X-axis acceleration detection units and a plurality of Y-axis acceleration detection units arranged on the outer coupling structure respectively, and a plurality of Z-axis acceleration detection units arranged on the outer coupling structure inner ring and the inner coupling structure; the Y-axis acceleration detection units are arranged adjacent to the X-axis acceleration detection units.

[0013] The plurality of X-axis acceleration detection units are symmetrically distributed about the Y-axis, and the plurality of X-axis acceleration detection units are symmetrically distributed about the X-axis.

[0014] The plurality of Y-axis acceleration detection units are symmetrically distributed about the X-axis, and the plurality of Y-axis acceleration detection units are symmetrically distributed about the Y-axis.

[0015] The plurality of Z-axis acceleration detection units are symmetrically distributed about the coordinate origin.

[0016] Preferably, the detection electrode plates include a first detection plate, a second detection plate, a third detection plate, a fourth detection plate, a fifth detection plate, a sixth detection plate, a seventh detection plate, an eighth detection plate, a ninth detection plate, and a tenth detection plate arranged in a ring shape and spaced apart from each other in the inner coupling structure; the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, and the fifth detection plate are symmetrically distributed about the X-axis with the sixth detection plate, the seventh detection plate, the eighth detection plate, the ninth detection plate, and the tenth detection plate, respectively.

[0017] The capacitor electrode plates on the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, and the fifth detection plate are arranged in positive-negative interlaced manner.

[0018] The capacitor electrode plates on the sixth detection plate, the seventh detection plate, the eighth detection plate, the ninth detection plate, and the tenth detection plate are arranged in opposite manner with the capacitor electrode plates on the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, and the fifth detection plate, respectively.

[0019] Preferably, the detection electrode plates include a first detection plate, a second detection plate, a third detection plate, a fourth detection plate, a fifth detection plate, a sixth detection plate, a seventh detection plate, an eighth detection plate, a ninth detection plate, a tenth detection plate, an eleventh detection plate, a twelfth detection plate, a thirteenth detection plate, a fourteenth detection plate, a fifteenth detection plate, and a sixteenth detection plate arranged in a ring shape and spaced apart from each other in the inner coupling structure; the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, the fifth detection plate, the sixth detection plate, the seventh detection plate, and the eighth detection plate are symmetrically distributed about the X-axis with the ninth detection plate, the tenth detection plate, the eleventh detection plate, the twelfth detection plate, the thirteenth detection plate, the fourteenth detection plate, the fifteenth detection plate, and the sixteenth detection plate, respectively.

[0020] The capacitor electrode plates on the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, the fifth detection plate, the sixth detection plate, the seventh detection plate, and the eighth detection plate are arranged in positive-negative interlaced manner.

[0021] The capacitor plates of the ninth detection plate, the tenth detection plate, the eleventh detection plate, the twelfth detection plate, the thirteenth detection plate, the fourteenth detection plate, the fifteenth detection plate and the sixteenth detection plate are oppositely arranged with the capacitor plates on the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, the fifth detection plate, the sixth detection plate, the seventh detection plate and the eighth detection plate.

[0022] Preferably, the detection plates include the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, the fifth detection plate, the sixth detection plate, the seventh detection plate and the eighth detection plate arranged in a ring shape inside the inner ring of the outer coupling structure and the inner coupling structure; the first detection plate, the second detection plate, the third detection plate and the fourth detection plate are symmetrically distributed about the X axis with the fifth detection plate, the sixth detection plate, the seventh detection plate and the eighth detection plate.

[0023] The capacitor plates on the first detection plate, the second detection plate, the third detection plate and the fourth detection plate are arranged in positive-negative interlaced manner.

[0024] The capacitor plates of the fifth detection plate, the sixth detection plate, the seventh detection plate and the eighth detection plate are oppositely arranged with the capacitor plates on the first detection plate, the second detection plate, the third detection plate and the fourth detection plate.

[0025] Preferably, the detection plates include the first detection plate, the second detection plate, the third detection plate, the fourth detection plate, the fifth detection plate and the sixth detection plate arranged in a ring shape inside the inner ring of the outer coupling structure and the inner coupling structure; the first detection plate, the second detection plate and the third detection plate are symmetrically distributed about the X axis with the fourth detection plate, the fifth detection plate and the sixth detection plate.

[0026] The capacitor plates on the first detection plate, the second detection plate and the third detection plate are arranged in positive-negative interlaced manner.

[0027] The fourth detection plate, the fifth detection plate and the sixth detection plate are oppositely arranged with the capacitor plates on the first detection plate, the second detection plate and the third detection plate.

[0028] Preferably, the detection plates include first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates arranged side by side along the X-axis direction of the inner coupling structure; the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates are symmetrically distributed about the X-axis with the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates, respectively;

[0029] The capacitor plates on the first and eighth detection plates are the same, the capacitor plates on two adjacent detection plates among the second to seventh detection plates are the same, and are arranged in positive-negative alternation with the capacitor plates on the first and eighth detection plates, respectively.

[0030] The ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates are arranged in reverse with the capacitor plates on the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates, respectively. Advantageous effects

[0031] Compared with the prior art, the accelerometer of the application has the following beneficial effects: two seesaw structures are arranged opposite to each other, the outer coupling structure includes an inner ring of the outer coupling structure and an outer ring of the outer coupling structure surrounding the outer side of the inner ring of the outer coupling structure, the two seesaw structures are coupled to the inner ring of the outer coupling structure, respectively, the anchor points are uniformly distributed at the center of the outer coupling structure, and the inner coupling structure is annularly distributed around the anchor points, so that the structure is less affected by stress during processing and has smaller process error; at the same time, when the outer coupling structure is deformed due to stress, the positive and negative capacitor plates have similar deformation in the initial state (without acceleration), so that the capacitor offset is small, and the overall structure has higher robustness; the detection structure further includes a first elastic member connecting the inner ring of the outer coupling structure and the corresponding seesaw structure, a second elastic member connecting the inner ring of the outer coupling structure and the outer ring of the outer coupling structure, and a third elastic member connecting the detection plate and the corresponding seesaw structure, so that the overall detection effect is improved by the multiple elastic members. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0033] Fig. 1 is a structural schematic diagram of an electronic device provided by an embodiment of the present application;

[0034] Fig. 2 is a structural schematic diagram of a Z-axis detection electrode plate of the embodiment of the present application;

[0035] Fig. 3 is a schematic diagram of an X-axis detection mode of the embodiment of the present application;

[0036] Fig. 4 is a schematic diagram of a Y-axis detection mode of the embodiment of the present application;

[0037] Fig. 5 is a schematic diagram of a Z-axis detection mode of the embodiment of the present application;

[0038] Fig. 6 is a structural schematic diagram of an electronic device provided by an embodiment of the present application;

[0039] Fig. 7 is a structural schematic diagram of a Z-axis detection electrode plate of the embodiment of the present application;

[0040] Fig. 8 is a schematic diagram of an X-axis detection mode of the embodiment of the present application;

[0041] Fig. 9 is a schematic diagram of a Y-axis detection mode of the embodiment of the present application;

[0042] Fig. 10 is a schematic diagram of a Z-axis detection mode of the embodiment of the present application;

[0043] Fig. 11 is a structural schematic diagram of an electronic device provided by an embodiment of the present application;

[0044] Fig. 12 is a structural schematic diagram of a Z-axis detection electrode plate of the embodiment of the present application;

[0045] Fig. 13 is a schematic diagram of an X-axis detection mode of the embodiment of the present application;

[0046] Fig. 14 is a schematic diagram of a Y-axis detection mode of the embodiment of the present application;

[0047] Fig. 15 is a schematic diagram of a Z-axis detection mode of the embodiment of the present application;

[0048] Fig. 16 is a structural schematic diagram of an electronic device provided by an embodiment of the present application;

[0049] Fig. 17 is a structural schematic diagram of a Z-axis detection electrode plate of the embodiment of the present application;

[0050] Fig. 18 is a schematic diagram of an X-axis detection mode of the fourth embodiment of the present application;

[0051] Fig. 19 is a schematic diagram of a Y-axis detection mode of the fourth embodiment of the present application;

[0052] Fig. 20 is a schematic diagram of a Z-axis detection mode of the fourth embodiment of the present application;

[0053] Fig. 21 is a schematic diagram of the structure of an electronic device according to the fifth embodiment of the present application;

[0054] Fig. 22 is a schematic diagram of the structure of a Z-axis detection electrode plate according to the fifth embodiment of the present application;

[0055] Fig. 23 is a schematic diagram of an X-axis detection mode according to the fifth embodiment of the present application;

[0056] Fig. 24 is a schematic diagram of a Y-axis detection mode according to the fifth embodiment of the present application;

[0057] Fig. 25 is a schematic diagram of a Z-axis detection mode according to the fifth embodiment of the present application;

[0058] Fig. 26 is a schematic diagram of the structure of an XZ two-axis acceleration detection unit according to the second embodiment of the present application;

[0059] Fig. 27 is a schematic diagram of an X-axis detection mode according to Fig. 26;

[0060] Fig. 28 is a schematic diagram of a Z-axis detection mode according to Fig. 26;

[0061] Fig. 29 is a schematic diagram of the structure of a YZ two-axis acceleration detection unit according to the second embodiment of the present application;

[0062] Fig. 30 is a schematic diagram of a Y-axis detection mode according to Fig. 29;

[0063] Fig. 31 is a schematic diagram of a Z-axis detection mode according to Fig. 29.

[0064] In the figure, 100, accelerometer, 1, center line, 2, detection structure, 21, anchor point, 22, seesaw structure, 23, inner side coupling structure, 24, outer side coupling structure, 241, inner ring of outer side coupling structure, 242, outer ring of outer side coupling structure, 25, displacement detection assembly, 251, X-axis acceleration detection unit, 252, Y-axis acceleration detection unit, 253, Z-axis acceleration detection unit, 26, detection pole plate, 261', first detection plate, 262', second detection plate, 263', third detection plate, 264', fourth detection plate, 265', fifth detection plate, 266', sixth detection plate, 267', seventh detection plate, 268', eighth detection plate, 269', ninth detection plate, 2610', tenth detection plate, 261'', first detection plate, 262'', second detection plate, 263'', third detection plate, 264'', fourth detection plate, 265'', fifth detection plate, 266'', sixth detection plate, 267'', seventh detection plate, 268'', eighth detection plate, 269'', ninth detection plate, 2610'', tenth detection plate, 2611'', eleventh detection plate, 2612'', twelfth detection plate, 2613'', thirteenth detection plate, 2614'', fourteenth detection plate, 2615'', fifteenth detection plate, 2616'', sixteenth detection plate, 261''', first detection plate, 262''', second detection plate, 263''', third detection plate, 264''', fourth detection plate, 265''', fifth detection plate, 266''', sixth detection plate, 2615, first detection plate, 2625, second detection plate, 2635, third detection plate, 2645, fourth detection plate, 2655, fifth detection plate, 2665, sixth detection plate, 2675, seventh detection plate, 2685, eighth detection plate, 2695, ninth detection plate, 26105, tenth detection plate, 26115, eleventh detection plate, 26125, twelfth detection plate, 26135, thirteenth detection plate, 26145, fourteenth detection plate, 3, first elastic member, 4, second elastic member, 5, third elastic member, 6, connecting beam. Embodiments of the present application

[0065] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0066] Embodiment one

[0067] Referring to FIG. 1-2, the embodiment of the present application provides an accelerometer 100, which comprises an outer coupling structure 24, a detection structure 2 connected to the outer coupling structure 24, and an inner coupling structure 23, the detection structure 2 comprises anchor points 21 connected to the outer coupling structure 24, two seesaw structures 22 elastically connected to the anchor points 21, and a displacement detection assembly 25 arranged on the outer coupling structure 24 and the inner coupling structure 23; the inner sides of the two seesaw structures 22 are coupled to the inner coupling structure 23, and the outer sides of the two seesaw structures 22 are coupled to the outer coupling structure 24; the two seesaw structures 22 are oppositely arranged, the outer coupling structure 24 comprises an inner ring 241 of the outer coupling structure coupled to the outer sides of the two seesaw structures 22 and an outer ring 242 of the outer coupling structure surrounding the outer periphery of the inner ring 241 of the outer coupling structure; the accelerometer 100 further comprises a detection electrode plate 26 fixed to one side of the inner coupling structure 23 close to the outer coupling structure 24; the anchor points 21 are uniformly distributed at the central position of the outer coupling structure 24, and the inner coupling structure 23 is annularly distributed around the anchor points 21. Thus, the structure is less affected by stress during processing, and the process error is smaller. Meanwhile, the outer coupling structure 24 and the inner coupling structure 23 are annularly distributed around the anchor points 21 at 0-360°, so that when the outer coupling structure 24 of the structure is deformed due to stress, the positive and negative electrode plates have similar deformation in the initial state (without acceleration), so that the capacitance offset is small, and the structure has higher robustness.

[0068] In the embodiment, the outer coupling structure 24 is in a rectangular structure, and the anchor points 21 are uniformly distributed at the geometric center of the outer coupling structure 24.

[0069] The detection structure 2 further comprises a first elastic member 3 connecting the outer coupling structure inner ring 241 and the corresponding seesaw structure 22, a second elastic member 4 connecting the outer coupling structure inner ring 241 and the outer coupling structure outer ring 242, and a third elastic member 5 connecting the detection electrode plate 26 and the corresponding seesaw structure 22. The outer coupling structure inner ring 241 is connected to the corresponding seesaw structure 22 through the first elastic member 3, so that the detection mass of the outer coupling structure 24 has the ability to move under the action of X-axis acceleration. The outer coupling structure outer ring 242 is connected to the outer coupling structure inner ring 241 through the second elastic member 4, so that the detection mass of the outer coupling structure outer ring 242 has the ability to move under the action of Y-axis acceleration. The elastic connection design of the inner-outer ring split surface in-plane XY axis makes the rotational modal stiffness of the detection mass of the outer coupling structure 24 improve, the cross-coupling is reduced, and the cross-coupling is reduced. The detection electrode plate 26 is connected to the corresponding seesaw structure 22 through the third elastic member 5, which improves the small capacitance offset of the detection electrode plate 26, and the structure has higher robustness.

[0070] In the embodiment, the first elastic member 3 is an X-axis single-degree-of-freedom spring, the second elastic member 4 is a Y-axis single-degree-of-freedom spring, and the third elastic member 5 is a Z-axis single-degree-of-freedom spring. Among them, the first elastic member 3, the second elastic member 4 and the third elastic member 5 are taken as torsional springs, the accelerometer 100 is a symmetrical structure, that is, the accelerometer 100 is symmetrical on both sides of the center line 1, and the two seesaw structures 22 are respectively located on both sides of the center line 1. The end of the seesaw structure 22 close to the center line 1 is connected to the inner coupling structure 23, and the end of the seesaw structure 22 away from the center line 1 is connected to the X-axis single-degree-of-freedom spring. By sharing the same sensitive mass in the X-axis, Y-axis and Z-axis detection directions, the mass of the sensitive structure is increased in a limited space, and the structural sensitivity is improved.

[0071] The anchor points 21 are four in number and are uniformly distributed at the geometric center of the outer coupling structure 24. The Z-axis single-degree-of-freedom spring is connected to the seesaw structure 22 through the anchor point 21. There are four Z-axis single-degree-of-freedom springs, one end of each Z-axis single-degree-of-freedom spring near the center is connected to one anchor point 21, and the other end of the Z-axis single-degree-of-freedom spring is connected to the corresponding seesaw structure 22. Each anchor point 21 is arranged between the opposite ends of the corresponding seesaw structure 22, so that the two seesaw structures 22 rotate around their respective rotation axes (i.e., the rotation axis composed of the third elastic member 5 on the same side of the seesaw structure 22 and the anchor point 21) and are symmetrical with respect to the center line 1, which to some extent suppresses the rotation of the seesaw structure 22 around the Z-axis in the plane and reduces the cross coupling of the structure. It should be noted that in other embodiments, the third elastic member 5 can also be a tension spring or other types of elastic structure, which is not particularly limited here as long as it can satisfy the elastic connection between the seesaw structure 22 and the anchor point 21.

[0072] In the embodiment, the detection electrode plate 26 is arranged alternately with the plurality of positive and negative capacitance electrode plates on the outer coupling structure 24. When the outer coupling structure 24 is deformed due to stress, the positive and negative capacitance electrode plates are deformed in a bowl shape due to the presence of the anchor points 21 between the outer coupling structure 24 and the movable structure. The alternate arrangement allows the positive and negative capacitance electrode plates to have similar deformation in the initial state (without acceleration), thereby reducing the capacitance offset.

[0073] In the embodiment, the inner coupling structure 23 has a plurality of connecting beams 6, and the inner coupling structure 23 is connected to the connecting beams 6 of the two seesaw structures 22 through the connecting beams 6. This makes the constraint of the inner coupling structure 23 on the seesaw structure 22 stronger, improves the stiffness of the rotation parasitic mode of the outer coupling structure 24, increases the cross-suppression ratio of the structure, and reduces the cross coupling of the accelerometer 100.

[0074] In the embodiment, the length direction of the outer coupling structure 24 is defined as the X-axis direction, the width direction of the outer coupling structure 24 is defined as the Y-axis direction, and the thickness direction of the outer coupling structure 24 is defined as the Z-axis direction; the two seesaw structures 22 are symmetrically arranged on the outer coupling structure 24 about the Y-axis; the displacement detection assembly 25 includes a plurality of X-axis acceleration detection units 251 and a plurality of Y-axis acceleration detection units 252 arranged on the outer coupling structure 24, and a plurality of Z-axis acceleration detection units 253 arranged on the inner ring 241 of the outer coupling structure and the inner coupling structure 23. The Y-axis acceleration detection unit 252 is arranged adjacent to the X-axis acceleration detection unit 251.

[0075] The plurality of X-axis acceleration detection units 251 are symmetrically distributed with respect to the Y-axis, and the plurality of X-axis acceleration detection units 251 are symmetrically distributed with respect to the X-axis. The X-axis acceleration detection unit 251 includes a plurality of detection capacitors arranged side by side along the Y-axis.

[0076] The plurality of Y-axis acceleration detection units 252 are symmetrically distributed with respect to the X-axis, and the plurality of Y-axis acceleration detection units 252 are symmetrically distributed with respect to the Y-axis. The Y-axis acceleration detection unit 252 includes a plurality of detection capacitors arranged side by side along the X-axis.

[0077] The plurality of Z-axis acceleration detection units 253 are arranged in a central symmetric distribution with respect to the coordinate origin.

[0078] The X-axis acceleration detection unit 251 is arranged on the connection between the two sides of the same seesaw structure 22.

[0079] In the present embodiment, the detection electrode plate 26 includes a first detection plate 261', a second detection plate 262', a third detection plate 263', a fourth detection plate 264', a fifth detection plate 265', a sixth detection plate 266', a seventh detection plate 267', an eighth detection plate 268', a ninth detection plate 269', and a tenth detection plate 2610' arranged in a ring shape in the inner ring 241 of the outer coupling structure and the inner coupling structure 23. The first detection plate 261', the second detection plate 262', the third detection plate 263', the fourth detection plate 264', and the fifth detection plate 265' are symmetrically distributed with respect to the X-axis with the sixth detection plate 266', the seventh detection plate 267', the eighth detection plate 268', the ninth detection plate 269', and the tenth detection plate 2610', respectively.

[0080] The capacitor electrode plates on the first detection plate 261', the second detection plate 262', the third detection plate 263', the fourth detection plate 264', and the fifth detection plate 265' are arranged in a positive-negative alternating manner.

[0081] The capacitor electrode plates on the sixth detection plate 266', the seventh detection plate 267', the eighth detection plate 268', the ninth detection plate 269', and the tenth detection plate 2610' are arranged in an opposite manner with respect to the capacitor electrode plates on the first detection plate 261', the second detection plate 262', the third detection plate 263', the fourth detection plate 264', and the fifth detection plate 265'.

[0082] As shown in FIG. 3-5, corresponding X-axis, Y-axis and Z-axis detection modalities are shown. Among them, the entire accelerometer 100 is supported by two oppositely arranged seesaw structures 22, the inner coupling structure 23 couples the inner sides of the two seesaw structures 22, and the outer coupling structure 24 couples the outer sides of the two seesaw structures 22, so that the rotation of the two seesaw structures 22 around their respective rotation axes is symmetrical with respect to the center line 1, which to some extent suppresses the rotation of the seesaw structure 22 in the plane around the Z-axis, and reduces the cross coupling of the structure. The proof mass of the accelerometer 100 is distributed on the coupling structure, but mainly concentrates on the outer coupling structure 24. When the face-out Z-axis acceleration comes, the inner and outer coupling structures on both sides of the seesaw structure 22 move differentially with respect to the outer coupling structure 24 and the cavity cover. As shown in FIG. 2, the detection mass corresponding to all Z+ and Z- regions (where the positive and negative can be interchanged) moves in opposite directions in the Z-axis direction, causing the Z-axis detection capacitor disposed between the inner and outer coupling structures 24 and the corresponding outer coupling structure 24 or the cavity cover to change differentially, so that the Z-axis acceleration can be detected by detecting the change in the detection capacitor.

[0083] Specifically, the anchor point 21 is located in the middle of the entire structure, so that the structure is less affected by stress during processing, and the process error is smaller. The in-plane displacement detection assembly 25 detects the translation caused by the motion of the proof mass in the X / Y direction caused by in-plane acceleration, and the out-of-plane capacitive detection electrode plate 26 detects the rotation of the seesaw structure 22 caused by the motion of the proof mass in the Z direction caused by out-of-plane acceleration.

[0084] In this embodiment, Z+, Z- are the capacitive plates of the corresponding outer coupling structure 24 and detection electrode plate 26. By supplementing the description of the Z-axis detection electrode plate 26 and the corresponding capacitive plate on the outer coupling structure 24 or CAP (cavity cover), as shown in FIG. 2, Z+, Z- are symmetrically distributed along axis 1, axis 2 and axis 3, axis 4, and axis 1, axis 2 and axis 3, axis 4 intersect near the center origin of the entire structure, which can reduce the initial capacitive offset of the Z-axis.

[0085] Example two

[0086] Referring to FIGS. 6-10, on the basis of the first embodiment, the detection electrode plate 26 comprises a first detection plate 261", a second detection plate 262", a third detection plate 263", a fourth detection plate 264", a fifth detection plate 265", a sixth detection plate 266", a seventh detection plate 267", an eighth detection plate 268", a ninth detection plate 269", a tenth detection plate 2610", an eleventh detection plate 2611", a twelfth detection plate 2612", a thirteenth detection plate 2613", a fourteenth detection plate 2614", a fifteenth detection plate 2615", and a sixteenth detection plate 2616" arranged in the outer coupling structure inner ring 241 and the inner coupling structure 23 in a ring shape; the first detection plate 261", the second detection plate 262", the third detection plate 263", the fourth detection plate 264", the fifth detection plate 265", the sixth detection plate 266", the seventh detection plate 267", and the eighth detection plate 268" are symmetrically distributed about the X axis with the ninth detection plate 269", the tenth detection plate 2610", the eleventh detection plate 2611", the twelfth detection plate 2612", the thirteenth detection plate 2613", the fourteenth detection plate 2614", the fifteenth detection plate 2615", and the sixteenth detection plate 2616", respectively.

[0087] The capacitor electrode plates on the first detection plate 261", the second detection plate 262", the third detection plate 263", the fourth detection plate 264", the fifth detection plate 265", the sixth detection plate 266", the seventh detection plate 267", and the eighth detection plate 268" are arranged in positive-negative alternation.

[0088] The capacitor electrode plates of the ninth detection plate 269", the tenth detection plate 2610", the eleventh detection plate 2611", the twelfth detection plate 2612", the thirteenth detection plate 2613", the fourteenth detection plate 2614", the fifteenth detection plate 2615", and the sixteenth detection plate 2616" are arranged in opposite positions with the capacitor electrode plates on the first detection plate 261", the second detection plate 262", the third detection plate 263", the fourth detection plate 264", the fifth detection plate 265", the sixth detection plate 266", the seventh detection plate 267", and the eighth detection plate 268", respectively.

[0089] Specifically, the detection electrode plate 26 of the Z axis and the corresponding capacitor electrode plate on the outer coupling structure 24 or the CAP (cavity cover) are supplemented as shown in FIG. 7. Z1+, Z1- are completely symmetrically distributed along axis 1, Z2+, Z2- are completely symmetrically distributed along axis 2, Z3+, Z3- are completely symmetrically distributed along axis 4 (Y axis), all positive and negative capacitor electrode plates are completely symmetrically distributed along axis 3 (X axis), and axis 1, axis 2, axis 3, and axis 4 intersect at the center origin of the entire structure. This arrangement further reduces the initial capacitance offset of the Z axis.

[0090] As shown in FIGS. 26-28, FIG. 26 is an X / Z dual-axis accelerometer derived from this embodiment, FIGS. 27 and 28 are the X-axis and Z-axis detection modes thereof, respectively, embodying the X-axis and Z-axis detection modes; as shown in FIGS. 29-31, FIG. 29 is a Y / Z dual-axis accelerometer derived from this embodiment, FIGS. 30 and 31 are the Y-axis and Z-axis detection modes thereof, respectively, embodying the Y-axis and Z-axis detection modes.

[0091] Embodiment Three

[0092] As shown in FIGS. 11-12, in this embodiment, the detection electrode plate 26 includes a first detection plate 261''', a second detection plate 262''', a third detection plate 263''', a fourth detection plate 264''', a fifth detection plate 265''', a sixth detection plate 266''', a seventh detection plate 267''', and an eighth detection plate 268''' arranged in a ring shape between the outer coupling structure inner ring 241 and the inner coupling structure 23; the first detection plate 261''', the second detection plate 262''', the third detection plate 263''', and the fourth detection plate 264''' are symmetrically distributed about the X axis with the fifth detection plate 265''', the sixth detection plate 266''', the seventh detection plate 267''', and the eighth detection plate 268'''.

[0093] The capacitor electrode plates on the first detection plate 261''', the second detection plate 262''', the third detection plate 263''', and the fourth detection plate 264''' are arranged in positive and negative alternation.

[0094] The capacitor electrode plates of the fifth detection plate 265''', the sixth detection plate 266''', the seventh detection plate 267''', and the eighth detection plate 268''' are arranged in opposite positions with the capacitor electrode plates on the first detection plate 261''', the second detection plate 262''', the third detection plate 263''', and the fourth detection plate 264'''.

[0095] Specifically, the detection electrode plate 26 of the Z axis and the corresponding capacitor plate on the outer coupling structure 24 or the CAP (cavity cover) (as shown in FIG. 12) are described in detail. They are symmetrical along the X axis (axis 3) and the Y axis (axis 4). All Z+ and Z- capacitor plates are completely symmetrical along the axis 1, the axis 2, the axis 3, and the axis 4, and the axis 1, the axis 2, the axis 3, and the axis 4 intersect at the center origin of the entire structure. In addition, the center of mass of all Z+ and Z- capacitor plates is equal in distance from the center origin. As shown in FIGS. 13-15, the corresponding X axis, Y axis, and Z axis detection modes are shown. This arrangement further reduces the initial Z axis capacitance offset.

[0096] Embodiment four

[0097] Referring to FIGS. 16-20, in the present embodiment, the detection electrode plate 26 includes a first detection plate 261’’’’, a second detection plate 262’’’’, a third detection plate 263’’’’, a fourth detection plate 264’’’’, a fifth detection plate 265’’’’, and a sixth detection plate 266’’’’ arranged in a ring shape in the inner ring 241 of the outer coupling structure and the inner coupling structure 23; the first detection plate 261’’’’, the second detection plate 262’’’’, and the third detection plate 263’’’’ are symmetrically distributed about the X axis with the fourth detection plate 264’’’’, the fifth detection plate 265’’’’, and the sixth detection plate 266’’’’ respectively;

[0098] The capacitor plates on the first detection plate 261’’’’, the second detection plate 262’’’’, and the third detection plate 263’’’’ are arranged in positive and negative staggered arrangement;

[0099] The fourth detection plate 264’’’’, the fifth detection plate 265’’’’, and the sixth detection plate 266’’’’ are arranged in opposite arrangement with the capacitor plates on the first detection plate 261’’’’, the second detection plate 262’’’’, and the third detection plate 263’’’’ respectively.

[0100] Specifically, the detection electrode plate 26 of the Z axis and the corresponding capacitor plate on the outer coupling structure 24 or the CAP (cavity cover) (as shown in FIG. 17) are described in detail. Z1- / Z6+, Z2+ / Z5-, Z3- / Z4+ are symmetrical along the axis 3 (X axis), Z1- and Z4+ are rotationally symmetrical in the quadrant formed by the axis 2 and the axis 3, Z3- and Z6+ are rotationally symmetrical in the quadrant formed by the axis 1 and the axis 3, and the axis 1, the axis 2, and the axis 3 intersect at the center origin of the entire structure. This arrangement further reduces the initial Z axis capacitance offset.

[0101] Embodiment five

[0102] Referring to FIGS. 21-22, in the embodiment, the detection electrode plate 26 includes first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, and sixteenth detection plates 2615, 2625, 2635, 2645, 2655, 2665, 2675, 2685, 2695, 26105, 26115, 26125, 26135, 26145, 26155, and 26165, respectively, arranged side by side along the X-axis in the outer coupling structure inner ring 241 and the inner coupling structure 23; the first, second, third, fourth, fifth, sixth, seventh, and eighth detection plates 2615, 2625, 2635, 2645, 2655, 2665, 2675, and 2685 are symmetrically distributed about the X-axis with the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, and sixteenth detection plates 2695, 26105, 26115, 26125, 26135, 26145, 26155, and 26165, respectively.

[0103] The capacitor electrode plates on the first and eighth detection plates 2615 and 2685 are the same, the capacitor electrode plates on adjacent two detection plates among the second to seventh detection plates 2625 to 2675 are the same, and are arranged in positive-negative alternation with the capacitor electrode plates on the first and eighth detection plates 2615 and 2685, respectively; the capacitor electrode plates on the fourth, fifth, and sixth detection plates 2645, 2655, and 2665 are arranged in positive-negative alternation; the capacitor electrode plates on adjacent third and fourth detection plates 2635 and 2645 are arranged in the same manner.

[0104] The capacitor electrode plates on the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth, and sixteenth detection plates 2695, 26105, 26115, 26125, 26135, 26145, 26155, and 26165 are arranged in reverse to the capacitor electrode plates on the first, second, third, fourth, fifth, sixth, seventh, and eighth detection plates 2615, 2625, 2635, 2645, 2655, 2665, 2675, and 2685, respectively.

[0105] Specifically, the detection electrode plate 26 of the Z axis and the corresponding capacitor electrode plate on the outer coupling structure 24 or the CAP (cavity cover) are described in detail. In the direction of the axis 3 (X axis), the distance between Z1+~Z4+ and the axis 3 is equal to the distance between Z1-~Z4- and the axis 3, and the distance between Z5+~Z8+ and the axis 3 is equal to the distance between Z5-~Z8- and the axis 3. Therefore, when the structure is rotated or warped in the direction of the axis 3, the positive and negative capacitor electrode plates deform and offset each other, so the capacitance offset is zero. In the direction of the axis 4 (Y axis), the distance between Z1+~Z2+ and the axis 4 is equal to the distance between Z1-~Z2- and the axis 4, and the distance between Z5+~Z6+ and the axis 4 is equal to the distance between Z1-~Z2- and the axis 4. The distance between Z3+~Z4+ and the axis 4 is equal to the distance between Z1-~Z2- and the axis 4, and the distance between Z7+~Z8+ and the axis 4 is equal to the distance between Z1-~Z2- and the axis 4. Therefore, when the structure is rotated or warped in the direction of the axis 4, the positive and negative capacitor electrode plates deform and offset each other, so the capacitance offset is zero. As shown in FIGS. 23-25, the corresponding X axis, Y axis and Z axis detection modes are shown, and this arrangement further reduces the initial capacitance offset of the Z axis.

[0106] Compared with the related art, the accelerometer of the application, by oppositely arranging two seesaw structures, the outer coupling structure includes an inner ring of the outer coupling structure and an outer ring of the outer coupling structure surrounding the outer ring of the outer coupling structure, which are respectively coupled to the outer sides of the two seesaw structures; the accelerometer further includes a detection electrode plate, which is fixed to the side of the inner coupling structure close to the outer coupling structure; the anchor points are uniformly distributed at the center of the outer coupling structure, and the inner coupling structure is annularly distributed around the anchor points, so that the structure is less affected by stress during processing, and the process error is smaller; at the same time, when the outer coupling structure is deformed due to stress, the positive and negative electrode capacitor electrode plates have similar deformation in the initial state (without acceleration), so that the capacitance offset is small, and the overall structure has higher robustness; the detection structure further includes a first elastic member connecting the inner ring of the outer coupling structure and the corresponding seesaw structure, a second elastic member connecting the inner ring of the outer coupling structure and the outer ring of the outer coupling structure, and a third elastic member connecting the detection electrode plate and the corresponding seesaw structure; the overall detection effect is improved by arranging multiple elastic members.

[0107] The above is only an embodiment of the application, and it should be noted that those skilled in the art can make improvements without departing from the inventive concept, but these are within the scope of protection of the application.

Claims

1. An accelerometer comprising an outer coupling structure, a detection structure connected to the outer coupling structure, and an inner coupling structure, the detection structure comprising an anchor connected to the outer coupling structure, two seesaw structures elastically connected to the anchor, and a displacement detection assembly disposed on both the outer coupling structure and the inner coupling structure; the inner coupling of the two seesaw structures is connected to the inner coupling structure, and the outer coupling of the two seesaw structures is connected to the outer coupling structure; the two seesaw structures are oppositely disposed, the outer coupling structure comprises an outer coupling structure inner ring and an outer coupling structure outer ring, the outer coupling structure inner ring is coupled to the outer side of the two seesaw structures respectively, and the outer coupling structure outer ring is arranged around the outer periphery of the outer coupling structure inner ring; characterized in that, The accelerometer further comprises a detection electrode plate fixed to the inner coupling structure near a side of the outer coupling structure; the anchor points are uniformly distributed at the central position of the outer coupling structure, and the inner coupling structure is distributed around the anchor points; The detection structure further comprises a first elastic member connecting the inner ring of the outer coupling structure and the corresponding seesaw structure, a second elastic member connecting the inner ring of the outer coupling structure and the outer ring of the outer coupling structure, and a third elastic member connecting the detection electrode plate and the corresponding seesaw structure.

2. The accelerometer of claim 1, wherein The anchor points include four anchor points, which are uniformly distributed at the geometric center of the outer coupling structure.

3. The accelerometer of claim 1, wherein, The inner ring of the outer coupling structure and the plurality of positive and negative capacitance electrode plates on the inner coupling structure are staggered.

4. The accelerometer of claim 1, wherein, The inner coupling structure has a plurality of connecting beams, and the inner coupling structure is connected to two seesaw structures through the connecting beams.

5. The accelerometer of claim 1, wherein, The length direction of the outer coupling structure is defined as the X-axis direction, the width direction of the outer coupling structure is defined as the Y-axis direction, and the thickness direction of the outer coupling structure is defined as the Z-axis direction; the two seesaw structures are symmetrically arranged on the outer coupling structure about the Y-axis; the displacement detection assembly comprises a plurality of X-axis acceleration detection units and a plurality of Y-axis acceleration detection units arranged on the outer coupling structure, and a plurality of Z-axis acceleration detection units arranged on the inner ring of the outer coupling structure and the inner coupling structure; the Y-axis acceleration detection units are arranged adjacent to the X-axis acceleration detection units; The plurality of X-axis acceleration detection units are symmetrically distributed about the Y-axis, and the plurality of X-axis acceleration detection units are symmetrically distributed about the X-axis; The plurality of Y-axis acceleration detection units are symmetrically distributed about the X-axis, and the plurality of Y-axis acceleration detection units are symmetrically distributed about the Y-axis; The plurality of Z-axis acceleration detection units are centrally symmetrically arranged about the coordinate origin.

6. The accelerometer of claim 5, wherein, The detection electrode plate comprises a first detection plate, a second detection plate, a third detection plate, a fourth detection plate, a fifth detection plate, a sixth detection plate, a seventh detection plate, an eighth detection plate, a ninth detection plate and a tenth detection plate arranged in a ring shape and spaced apart on the inner ring of the outer coupling structure and the inner coupling structure, the first detection plate, the second detection plate, the third detection plate, the fourth detection plate and the fifth detection plate are symmetrically distributed about the X-axis with the sixth detection plate, the seventh detection plate, the eighth detection plate, the ninth detection plate and the tenth detection plate; The capacitance electrode plates on the first detection plate, the second detection plate, the third detection plate, the fourth detection plate and the fifth detection plate are staggered. The capacitance electrode plates on the sixth detection plate, the seventh detection plate, the eighth detection plate, the ninth detection plate and the tenth detection plate are arranged in opposite positions with the capacitance electrode plates on the first detection plate, the second detection plate, the third detection plate, the fourth detection plate and the fifth detection plate.

7. The accelerometer of claim 5, wherein The detection electrode plates include first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates arranged in a ring shape and spaced apart from each other between the inner ring of the outer coupling structure and the inner coupling structure; the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates are symmetrically distributed about the X axis with the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates, respectively; The capacitor electrode plates on the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates are arranged in positive-negative interlaced manner; The capacitor electrode plates of the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates are arranged in opposite manner with the capacitor electrode plates on the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates, respectively.

8. The accelerometer of claim 5, wherein, The detection electrode plates include first, second, third, fourth, fifth, sixth, seventh and eighth detection plates arranged in a ring shape and spaced apart from each other between the inner ring of the outer coupling structure and the inner coupling structure; the first, second, third and fourth detection plates are symmetrically distributed about the X axis with the fifth, sixth, seventh and eighth detection plates, respectively; The capacitor electrode plates on the first, second, third and fourth detection plates are arranged in positive-negative interlaced manner; The capacitor electrode plates of the fifth, sixth, seventh and eighth detection plates are arranged in opposite manner with the capacitor electrode plates on the first, second, third and fourth detection plates, respectively.

9. The accelerometer of claim 5, wherein, The detection electrode plates include first, second, third, fourth, fifth and sixth detection plates arranged in a ring shape and spaced apart from each other between the inner ring of the outer coupling structure and the inner coupling structure; the first, second and third detection plates are symmetrically distributed about the X axis with the fourth, fifth and sixth detection plates, respectively; The capacitor electrode plates on the first, second and third detection plates are arranged in positive-negative interlaced manner; The fourth detection plate, the fifth detection plate and the sixth detection plate are oppositely arranged with the capacitor plates on the first detection plate, the second detection plate and the third detection plate.

10. The accelerometer of claim 5, wherein, The detection plates include first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates arranged side by side along the X-axis direction within the inner ring of the outer coupling structure and the inner coupling structure; the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates are symmetrically distributed about the X-axis with the ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates; The capacitor plates on the first detection plate and the eighth detection plate are the same, the capacitor plates on two adjacent detection plates among the second to seventh detection plates are the same, and are arranged in positive-negative interlaced manner with the capacitor plates on the first detection plate and the eighth detection plate; The ninth, tenth, eleventh, twelfth, thirteenth, fourteenth, fifteenth and sixteenth detection plates are oppositely arranged with the capacitor plates on the first, second, third, fourth, fifth, sixth, seventh and eighth detection plates.

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