Acceleration sensor

Abstract

An acceleration sensor, comprising a substrate, anchor points (1), inner side support units (2), a first seesaw unit (3), a second seesaw unit (4) and out-of-plane displacement measuring units (5). The middle of each inner side support unit (2) is fixed to the substrate by means of an anchor point (1); the first seesaw unit (4) is elastically connected to the outer side of a first end of each inner side support unit (2), and the second seesaw unit (4) is elastically connected to the outer side of a second end of each inner side support unit (2); the first seesaw unit (3) and the second seesaw unit (4) are each symmetrically distributed along the symmetry axis (100) of the acceleration sensor; the first seesaw unit (3) forms two first seesaw structures on two sides of the symmetry axis (100) respectively, and the second seesaw unit forms two second seesaw structures on two sides of the symmetry axis (100) respectively. The present invention achieves the technical effects of reducing the impact of Y-axis angular acceleration on acceleration sensors, and improving the cross-axis suppression ratio of acceleration sensors.

Description

An acceleration sensor Technical Field

[0001] The present invention belongs to the technical field of sensors, and in particular relates to an acceleration sensor. Background Art

[0002] Acceleration sensors include one or more proof masses for detecting acceleration. For example, some acceleration sensors include a proof mass configured to move within a plane to detect acceleration in the plane of the proof mass, and the proof mass configured to move out of plane to detect acceleration perpendicular to the plane of the proof mass. Acceleration can be detected using a capacitive sensor coupled to the proof mass.

[0003] When detecting out-of-plane acceleration, current acceleration sensors are easily affected by the y-axis angular acceleration, and the fork suppression is relatively low, which is not conducive to ensuring the accuracy of the acceleration sensor's detection of out-of-plane acceleration. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art and provide a new technical solution for an acceleration sensor.

[0005] According to one aspect of the present invention, there is provided an acceleration sensor, comprising:

[0006] A base, an anchor point, and an inner support unit, wherein a middle portion of the inner support unit is fixed to the base through the anchor point; the inner support unit includes a first end and a second end;

[0007] A first seesaw unit and a second seesaw unit, wherein the first seesaw unit is elastically connected to the outer side of the first end of the inner support unit, and the second seesaw unit is elastically connected to the outer side of the second end of the inner support unit; the first seesaw unit and the second seesaw unit are arranged opposite to each other, and the first seesaw unit and the second seesaw unit are symmetrically distributed along the symmetry axis of the acceleration sensor; the first seesaw unit forms two first seesaw structures on both sides of the symmetry axis, and the two first seesaw structures rotate along the first rotation axis; the second seesaw unit forms two second seesaw structures on both sides of the symmetry axis, and the two second seesaw structures rotate along the second rotation axis; the first rotation axis is arranged parallel to the second rotation axis, and the symmetry axis is perpendicular to the first rotation axis or the second rotation axis;

[0008] An out-of-plane displacement detection unit is provided on both the first seesaw unit and the second seesaw unit.

[0009] Optionally, a first groove is provided on the outer side of the first seesaw unit, and a second groove is provided on the inner side of the second seesaw unit, part of the first seesaw unit is embedded in the second groove and part of the second seesaw unit is embedded in the first groove to form a nested structure, and the nested structure is located between the first rotating shaft and the second rotating shaft.

[0010] Optionally, the acceleration sensor further includes a first detection mass block and a second detection mass block;

[0011] Each of the first seesaw structures includes a first sub-rotating portion and a second sub-rotating portion, the first sub-rotating portion and the second sub-rotating portion are respectively located on opposite sides of the first rotating shaft, and a first groove is provided on an outer side of the second sub-rotating portion; each of the second seesaw structures includes a third sub-rotating portion and a fourth sub-rotating portion, the third sub-rotating portion and the fourth sub-rotating portion are respectively located on opposite sides of the second rotating shaft, and a second groove is provided on an inner side of the third sub-rotating portion;

[0012] The first detection mass block is located on the first sub-rotation portion, the second detection mass block is located on the fourth sub-rotation portion, and the first detection mass block and the second detection mass block are symmetrically arranged.

[0013] Optionally, the acceleration sensor further includes a coupling beam, which extends in a direction perpendicular to the symmetry axis, and one end of the coupling beam is connected to the second sub-rotation part, and the other end of the coupling beam is connected to the third sub-rotation part.

[0014] Optionally, the acceleration sensor further includes a first elastic member and a second elastic member, wherein the first seesaw unit is connected to the first end of the inner support unit via the first elastic member; and the second seesaw unit is connected to the second end of the inner support unit via the second elastic member.

[0015] The first elastic member is close to the first rotating shaft and extends in a direction parallel to the first rotating shaft; the second elastic member is close to the second rotating shaft and extends in a direction parallel to the second rotating shaft.

[0016] Optionally, the out-of-plane displacement detection unit is located in a region of the first seesaw unit away from the first rotation axis;

[0017] The out-of-plane displacement detection unit is located in a region of the second seesaw unit away from the second rotation axis.

[0018] Optionally, the two inner support units are symmetrically distributed along the symmetry axis; each of the inner support units is fixed to the base via an anchor point, and the anchor point is located on the inner side of the inner support unit.

[0019] Optionally, the two inner support units are symmetrically distributed along the symmetry axis, and the middle parts of the two inner support units are connected, and one anchor point is located at the connection between the two inner support units.

[0020] Optionally, the acceleration sensor further includes an X-axis acceleration detection structure, wherein the X-axis acceleration detection structure is used to detect acceleration along the X-axis direction;

[0021] The X-axis acceleration detection structure is located between the two inner support units, and the X-axis acceleration detection structure is symmetrically distributed along the symmetry axis.

[0022] Optionally, the acceleration sensor further includes a Y-axis acceleration detection structure, wherein the Y-axis acceleration detection structure is used to detect acceleration along the Y-axis direction;

[0023] The Y-axis acceleration detection structure is located between the two inner support units, and the Y-axis acceleration detection structure is symmetrically distributed along the symmetry axis.

[0024] Optionally, the acceleration sensor further includes an X-axis acceleration detection structure and a Y-axis acceleration detection structure, wherein the X-axis acceleration detection structure is used to detect acceleration along the X-axis direction; and the Y-axis acceleration detection structure is used to detect acceleration along the Y-axis direction.

[0025] The X-axis acceleration detection structure and the Y-axis acceleration detection structure are both located between the two inner support units, and the X-axis acceleration detection structure and the Y-axis acceleration detection structure are respectively located on opposite sides of the anchor point.

[0026] A technical effect of the present invention is:

[0027] In the embodiment of the present application, the first seesaw unit and the second seesaw unit are arranged opposite each other, and the first seesaw unit has two first seesaw structures symmetrically distributed along the symmetry axis, and the second seesaw unit has two second seesaw structures symmetrically distributed along the symmetry axis. Furthermore, both the first seesaw unit and the second seesaw unit are provided with an out-of-plane displacement detection unit.

[0028] Therefore, the first seesaw unit and the second seesaw unit are used as the out-of-plane acceleration detection structure, so that the first seesaw unit and the second seesaw unit can rotate in opposite directions along the Y-axis direction under the influence of acceleration in the out-of-plane direction (i.e., the Z-axis direction). The out-of-plane acceleration (i.e., the Z-axis acceleration) of the acceleration sensor can be detected by the out-of-plane displacement detection unit provided on the first seesaw unit and the second seesaw unit. At the same time, when the two first seesaw structures or the two second seesaw structures are subjected to undesirable Y-axis angular acceleration, the two first seesaw structures or the two second seesaw structures rotate in the same direction. The capacitance change of the out-of-plane displacement detection unit caused by the same rotation is offset during the detection by the out-of-plane displacement detection unit. Therefore, the layout of the two first seesaw structures and the two second seesaw structures greatly reduces the influence of the Y-axis angular acceleration on the acceleration sensor, improves the cross-rejection ratio of the acceleration sensor, and improves the accuracy of the acceleration sensor in detecting out-of-plane acceleration. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a schematic structural diagram of an acceleration sensor according to a first embodiment of the present invention;

[0030] FIG2 is a schematic diagram of the Z-axis detection mode of the acceleration sensor according to the first embodiment of the present invention;

[0031] 3 is a schematic diagram of the Z-axis parasitic mode of the acceleration sensor according to the first embodiment of the present invention;

[0032] FIG4 is a schematic structural diagram of an acceleration sensor according to a second embodiment of the present invention;

[0033] FIG5 is a schematic structural diagram of an acceleration sensor according to a third embodiment of the present invention;

[0034] 6 is a schematic diagram of a Z-axis detection mode of an acceleration sensor according to a third embodiment of the present invention;

[0035] FIG7 is a schematic structural diagram of a coupling beam of an acceleration sensor according to an embodiment of the present invention;

[0036] FIG8 is an enlarged view of the detail at point A in FIG7 ;

[0037] FIG9 is a schematic structural diagram of a coupling beam of an acceleration sensor according to another embodiment of the present invention;

[0038] Figure 10 is an enlarged view of the details of point A in Figure 9;

[0039] FIG11 is a schematic structural diagram of an acceleration sensor according to a fourth embodiment of the present invention;

[0040] FIG12 is a schematic structural diagram of an acceleration sensor according to a fifth embodiment of the present invention;

[0041] FIG13 is a schematic structural diagram of an acceleration sensor according to a sixth embodiment of the present invention;

[0042] FIG14 is a schematic structural diagram of an X-axis acceleration detection structure of an acceleration sensor according to an embodiment of the present invention;

[0043] FIG15 is a schematic structural diagram of a Y-axis acceleration detection structure of an acceleration sensor according to an embodiment of the present invention.

[0044] In the figure: 100, axis of symmetry; 200, first rotation axis; 300, second rotation axis; 1, anchor point; 2, inner support unit; 3, first seesaw unit; 31, first sub-rotation part; 32, second sub-rotation part; 33, first groove; 4, second seesaw unit; 41, third sub-rotation part; 42, fourth sub-rotation part; 43, second groove; 5, out-of-plane displacement detection unit; 61, first detection mass block; 62, second detection mass block; 7, coupling Combined beam; 81. First elastic member; 82. Second elastic member; 9. X-axis acceleration detection structure; 901. First mass block; 9021. First positive fixed electrode; 9022. First negative fixed electrode; 903. First torsion spring; 904. First mounting slot; 10. Y-axis acceleration detection structure; 101. Second mass block; 1021. Second positive fixed electrode; 1022. Second negative fixed electrode; 103. Second torsion spring; 104. Second mounting slot. Implementation Method

[0045] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0046] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0047] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of the features. Throughout the description of this application, unless otherwise specified, "plurality" means two or more. Furthermore, "and / or" in the specification and claims refers to at least one of the connected entities, and the character " / " generally indicates an "or" relationship between the connected entities.

[0048] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0050] It should be noted that the in-plane X-axis detection mode refers to the acceleration sensor being affected by the in-plane X-axis acceleration; the in-plane Y-axis detection mode refers to the acceleration sensor being affected by the in-plane Y-axis acceleration; the out-of-plane Z-axis detection mode refers to the acceleration sensor being affected by the out-of-plane Z-axis acceleration; and the out-of-plane Z-axis parasitic mode refers to the acceleration sensor being affected by both the out-of-plane Z-axis acceleration and the Y-axis angular acceleration. Example

[0051] Referring to Figures 1 to 3 , an acceleration sensor is provided according to one aspect of the present invention. To facilitate description of the acceleration sensor of the present invention, a three-dimensional XYZ coordinate system is established, where a first direction is defined as the X-axis, a second direction is defined as the Y-axis, and a third direction is defined as the Z-axis (i.e., the out-of-plane direction). The first, second, and third directions are mutually perpendicular.

[0052] In the embodiment of the present application, the acceleration sensor includes a substrate, an anchor point 1 , an inner support unit 2 , a first seesaw unit 3 , a second seesaw unit 4 and an out-of-plane displacement detection unit 5 .

[0053] Specifically, the middle portion of the inner supporting unit 2 is fixed to the base through the anchor point 1 ; the inner supporting unit 2 includes a first end and a second end.

[0054] More specifically, the first seesaw unit 3 is elastically connected to the outer side of the first end of the inner support unit 2, and the second seesaw unit 4 is elastically connected to the outer side of the second end of the inner support unit 2. The first seesaw unit 3 and the second seesaw unit 4 are arranged opposite each other and are symmetrically distributed along the symmetry axis 100 of the acceleration sensor. The first seesaw unit 3 forms two first seesaw structures on either side of the symmetry axis 100, and both first seesaw structures rotate along the first rotation axis 200. The second seesaw unit 4 forms two second seesaw structures on either side of the symmetry axis 100, and both second seesaw structures rotate along the second rotation axis 300. The first rotation axis 200 is arranged parallel to the second rotation axis 300, and the symmetry axis 100 is perpendicular to the first rotation axis 200 or the second rotation axis 300. The first rotation axis 200 and the second rotation axis 300 are distributed along the second direction, that is, along the Y-axis. The symmetry axis 100 is distributed along the X-axis direction.

[0055] The out-of-plane displacement detection unit 5 is provided on both the first seesaw unit 3 and the second seesaw unit 4 .

[0056] In the embodiment of the present application, a first seesaw unit 3 and a second seesaw unit 4 are used as the out-of-plane acceleration detection structure, so that the first seesaw unit 3 and the second seesaw unit 4 can rotate in opposite directions along the Y-axis direction under the influence of acceleration in the out-of-plane direction (i.e., the Z-axis direction). Therefore, the out-of-plane acceleration (i.e., the Z-axis acceleration) of the acceleration sensor can be detected by the out-of-plane displacement detection unit 5 provided on the first seesaw unit 3 and the second seesaw unit 4. Simultaneously, when the two first seesaw structures or the two second seesaw structures are subjected to an undesirable Y-axis angular acceleration, the two first seesaw structures or the two second seesaw structures rotate in the same direction. The capacitance changes of the out-of-plane displacement detection units 5 caused by the same rotation are offset during the detection by the out-of-plane displacement detection units 5. Therefore, the layout of the two first seesaw structures and the two second seesaw structures greatly reduces the influence of the Y-axis angular acceleration on the acceleration sensor, improves the cross-rejection ratio of the acceleration sensor, and enhances the accuracy of the acceleration sensor in detecting out-of-plane acceleration.

[0057] Optionally, a first groove 33 is provided on the outer side of the first seesaw unit 3, and a second groove 43 is provided on the inner side of the second seesaw unit 4, part of the first seesaw unit 3 is embedded in the second groove 43 and part of the second seesaw unit 4 is embedded in the first groove 33 to form a nested structure, and the nested structure is located between the first rotating shaft 200 and the second rotating shaft 300.

[0058] In the above embodiment, a nested structure is adopted between the first seesaw unit 3 and the second seesaw unit 4. The nested structure helps to extend the rotation arms of the first seesaw unit 3 and the second seesaw unit 4. At the same time, the out-of-plane displacement detection unit 5 can be arranged in an area farther from the rotation axis, thereby increasing the gain of the out-of-plane acceleration detection.

[0059] Optionally, the acceleration sensor further includes a first detection mass block 61 and a second detection mass block 62;

[0060] Each of the first seesaw structures includes a first sub-rotating portion 31 and a second sub-rotating portion 32, which are respectively located on opposite sides of the first rotating shaft 200, and a first groove 33 is provided on the outer side of the second sub-rotating portion 32; each of the second seesaw structures includes a third sub-rotating portion 41 and a fourth sub-rotating portion 42, which are respectively located on opposite sides of the second rotating shaft 300, and a second groove 43 is provided on the inner side of the third sub-rotating portion 41;

[0061] The first detection mass block 61 is located on the first sub-rotation portion 31 , and the second detection mass block 62 is located on the fourth sub-rotation portion 42 . The first detection mass block 61 and the second detection mass block 62 are symmetrically arranged.

[0062] In the above embodiment, the first detection mass block 61 and the second detection mass block 62 form an asymmetric detection mass, and the asymmetric detection mass is located at the far end of the seesaw structure, so that the rotation of the first seesaw structure and the second seesaw structure caused by the out-of-plane acceleration is more sensitive, thereby improving the gain of the acceleration sensor detection.

[0063] Exemplarily, a first detection mass is set at the position where the two first sub-rotating parts 31 are connected, and a second detection mass is set at the position where the two fourth sub-rotating parts 42 are connected, which helps to further increase the distance between the detection mass and the rotation axis, thereby significantly improving the sensitivity of the rotation of the first seesaw structure and the second seesaw structure caused by out-of-plane acceleration, so as to further improve the gain of the acceleration sensor detection.

[0064] Optionally, the acceleration sensor further includes a first elastic member 81 and a second elastic member 82, wherein the first seesaw unit 3 is connected to the first end of the inner support unit 2 via the first elastic member 81; and the second seesaw unit 4 is connected to the second end of the inner support unit 2 via the second elastic member 82.

[0065] The first elastic member 81 is close to the first rotating shaft 200 and extends in a direction parallel to the first rotating shaft 200 ; the second elastic member 82 is close to the second rotating shaft 300 and extends in a direction parallel to the second rotating shaft 300 .

[0066] In the above embodiment, the first elastic member 81 and the second elastic member 82 enable the acceleration sensor to provide support for the co-coupling of the movement of the first detection mass block 61 and the second detection mass block 62 along the third direction, thereby helping the acceleration sensor to realize the function of detecting external acceleration.

[0067] Optionally, the out-of-plane displacement detection unit 5 is located in a region of the first seesaw unit 3 away from the first rotation axis 200 ;

[0068] The out-of-plane displacement detection unit 5 is located in a region of the second seesaw unit 4 away from the second rotation axis 300 .

[0069] In the above embodiment, since part of the out-of-plane displacement detection unit 5 is located in the area of ​​the first seesaw unit 3 away from the first rotation axis 200 and part of the out-of-plane displacement detection unit 5 is located in the area of ​​the second seesaw unit 4 away from the second rotation axis 300, the gain of the out-of-plane acceleration detection is greater.

[0070] Optionally, the two inner support units 2 are symmetrically distributed along the symmetry axis 100 ; each of the inner support units 2 is fixed to the base via one anchor point 1 , and the anchor point 1 is located on the inner side of the inner support unit 2 .

[0071] In the above embodiment, the two anchor points 1 are located in the middle of the accelerometer structure, minimizing the impact of stress and other factors on the accelerometer, thereby improving its anti-interference capabilities. Furthermore, the first seesaw unit 3 and the second seesaw unit 4 are indirectly fixed to the substrate via the two anchor points 1, respectively, enhancing the stability of the accelerometer structure. Example

[0072] This embodiment provides another acceleration sensor, the structure of which is substantially the same as that of the embodiment 1, and only the different parts are described below.

[0073] In an embodiment, referring to FIG. 4 , the two inner support units 2 are symmetrically distributed along the symmetry axis 100 , and the middle portions of the two inner support units 2 are connected, and one anchor point 1 is located at the connection between the two inner support units 2 .

[0074] In the above embodiment, anchor point 1 is located in the middle of the entire acceleration sensor structure, which makes the acceleration sensor less affected by factors such as stress, improves the acceleration sensor's anti-interference ability, and further improves the acceleration sensor's ability to resist interference from factors such as stress. Example

[0075] This embodiment provides another acceleration sensor, the structure of which is substantially the same as that of the embodiment 1, and only the different parts are described below.

[0076] In an embodiment, referring to Figures 5 to 10, optionally, the acceleration sensor further includes a coupling beam 7, wherein the coupling beam 7 extends in a direction perpendicular to the axis of symmetry 100, and one end of the coupling beam 7 is connected to the second sub-rotating portion 32, and the other end is connected to the third sub-rotating portion 41.

[0077] In the above embodiment, by setting a coupling beam 7 between the first seesaw unit 3 and the second seesaw unit 4, the coupling beam 7 can weaken the same-direction rotation of the first seesaw unit 3 and the second seesaw unit 4, further suppressing the influence of the y-axis angular acceleration, and helping to further improve the accuracy of the acceleration sensor in detecting external acceleration.

[0078] In a specific embodiment, out-of-plane displacement detection units 5 are provided on the first sub-rotating portion 31, the second sub-rotating portion 32, the third sub-rotating portion 41, and the fourth sub-rotating portion 42. Some of the out-of-plane displacement detection units 5 are located on the first seesaw unit 3 away from the first rotation axis 200, and some of the out-of-plane displacement detection units 5 are located on the second seesaw unit 4 away from the second rotation axis 300. The multiple out-of-plane displacement detection units 5 are symmetrically distributed along the symmetry axis 100.

[0079] 5 , the coupling beam 7 is in a bar shape, with one end of the coupling beam 7 fixed to the bottom wall of the first groove 33 and the other end fixed to the bottom wall of the second groove 43. This makes the structure of the coupling beam 7 relatively simple, facilitating the assembly of the acceleration sensor.

[0080] In some embodiments, as shown in Figures 7 and 8 , the coupling beam 7 includes two parallel sub-beams. One end of each sub-beam is fixed to the bottom wall of the first groove 33, and the other end is fixed to the bottom wall of the second groove 43. This further improves the ability of the coupling beam 7 to reduce the co-directional rotation of the first seesaw unit 3 and the second seesaw unit 4, thereby better suppressing the influence of y-axis angular acceleration.

[0081] In other embodiments, as shown in Figures 9 and 10 , the coupling beam 7 is in the form of a rectangular ring. The middle portion of one side of the coupling beam 7 is fixed to the inner wall of the first groove 33, and the middle portion of the other side of the coupling beam 7 is fixed to the inner wall of the second groove 43. This makes the structural design of the coupling beam 7 more reasonable, effectively reducing the ability of the first seesaw unit 3 and the second seesaw unit 4 to rotate in the same direction.

[0082] It should be noted that Figure 2 is a schematic diagram of the Z-axis detection mode of the accelerometer without coupling beam 7, Figure 3 is a schematic diagram of the Z-axis parasitic mode of the accelerometer without coupling beam 7, and Figure 6 is a schematic diagram of the Z-axis detection mode of the accelerometer with coupling beam 7. The out-of-plane displacement detection unit 5 detects acceleration in the Z-axis direction (i.e., out-of-plane acceleration), causing the first seesaw unit 3 and the second seesaw unit 4 to rotate in opposite directions. However, in the parasitic mode, the first seesaw unit 3 and the second seesaw unit 4 rotate in the same direction about the Y-axis under the action of the Y-axis angular acceleration. To weaken the influence of the parasitic mode, a coupling beam 7 is connected to the first seesaw unit 3 and the second seesaw unit 4 to reduce the influence of the parasitic mode, that is, to weaken the same-direction rotation of the first seesaw unit 3 and the second seesaw unit 4 about the Y-axis. This further improves the cross-rejection ratio of the accelerometer and significantly enhances the detection accuracy of the acceleration sensor.

[0083] In one embodiment, the out-of-plane displacement detection unit 5 includes a first out-of-plane detection plate and a second out-of-plane detection plate, which are opposite to each other and constitute a capacitor plate structure. The first out-of-plane detection plate is located on the base or the cavity cover, and the second out-of-plane detection plate is located on the first seesaw unit 3 and the second seesaw unit 4. Example

[0084] This embodiment provides another acceleration sensor, the structure of which is substantially the same as that of the embodiment 1, and only the different parts are described below.

[0085] In an embodiment, referring to FIG11 , the acceleration sensor further includes an X-axis acceleration detection structure 9 , wherein the X-axis acceleration detection structure 9 is used to detect acceleration along the X-axis direction;

[0086] The X-axis acceleration detection structure 9 is located between the two inner support units 2 , and the X-axis acceleration detection structure 9 is symmetrically distributed along the symmetry axis 100 .

[0087] Exemplarily, the two X-axis acceleration detection structures 9 are located on opposite sides of the anchor point 1 , and the two X-axis acceleration detection structures 9 are symmetrically arranged.

[0088] In the above embodiment, the acceleration sensor can simultaneously detect acceleration along the X-axis direction and acceleration along the Z-axis direction to form a dual-axis accelerometer, thereby expanding the detection range of the acceleration sensor. Example

[0089] This embodiment provides another acceleration sensor, the structure of which is substantially the same as that of the embodiment 1, and only the different parts are described below.

[0090] In an embodiment, referring to FIG12 , the acceleration sensor further includes a Y-axis acceleration detection structure 10 , wherein the Y-axis acceleration detection structure 10 is used to detect acceleration along the Y-axis direction;

[0091] The Y-axis acceleration detection structure 10 is located between the two inner support units 2 , and the Y-axis acceleration detection structure 10 is symmetrically distributed along the symmetry axis 100 .

[0092] In the above embodiment, the acceleration sensor can simultaneously detect the acceleration along the Y-axis direction and the acceleration along the Z-axis direction to form a dual-axis accelerometer, thereby expanding the detection range of the acceleration sensor.

[0093] Exemplarily, the two Y-axis acceleration detection structures 10 are located on opposite sides of the anchor point 1 , and the two Y-axis acceleration detection structures 10 are symmetrically arranged. Example

[0094] This embodiment provides another acceleration sensor, the structure of which is substantially the same as that of the embodiment 1, and only the different parts are described below.

[0095] In an embodiment, referring to FIG13 , the acceleration sensor further includes an X-axis acceleration detection structure 9 and a Y-axis acceleration detection structure 10 , wherein the X-axis acceleration detection structure 9 is used to detect acceleration along the X-axis direction; the Y-axis acceleration detection structure 10 is used to detect acceleration along the Y-axis direction;

[0096] The X-axis acceleration detection structure 9 and the Y-axis acceleration detection structure 10 are both located between the two inner support units 2 , and the X-axis acceleration detection structure 9 and the Y-axis acceleration detection structure 10 are respectively located on opposite sides of the anchor point 1 .

[0097] In the above embodiment, the acceleration sensor can simultaneously detect acceleration along the X-axis, acceleration along the Y-axis, and acceleration along the Z-axis to form a three-axis accelerometer, which expands the detection range of the acceleration sensor and is very convenient to use.

[0098] Exemplarily, one X-axis acceleration detection structure 9 and one Y-axis acceleration detection structure 10 are respectively located on opposite sides of the anchor point 1 , thereby optimizing the structure of the acceleration sensor.

[0099] In one specific embodiment, referring to Figure 14 , the X-axis acceleration detection structure 9 includes a first mass 901 and a first capacitor group. The first mass 901 is secured to a substrate on either side by first torsion springs 903. First mounting slots 904 distributed along the Y-axis are spaced apart in the middle of the first mass 901, each containing a first capacitor group. The first capacitor group includes a first positive fixed electrode 9021 and a first negative fixed electrode 9022, which are distributed along the Y-axis direction. The middle portion of the first positive fixed electrode 9021 near the first negative fixed electrode 9022 is anchored to the substrate, and the middle portion of the first negative fixed electrode 9022 near the first positive fixed electrode 9021 is anchored to the substrate. The side of the first positive fixed electrode 9021 away from the first negative fixed electrode 9022 forms a first differential detection capacitor with the first mass block 901, and the side of the first negative fixed electrode 9022 away from the first positive fixed electrode 9021 forms a second differential detection capacitor with the first mass block 901.

[0100] When the first mass 901 is displaced to the left by the acceleration to the left along the X-axis, the capacitance spacing of the first differential detection capacitor decreases, and the capacitance spacing of the second differential detection capacitor increases. The capacitance difference between the first differential detection capacitor and the second differential detection capacitor changes in proportion to the acceleration to the left along the X-axis. By detecting the change in the capacitance difference, the real-time value of the acceleration to the left along the X-axis can be obtained.

[0101] Similarly, when the first mass 901 is displaced to the right by the acceleration along the X-axis, the real-time value of the acceleration to the right along the X-axis can also be obtained by detecting the change in the capacitance difference.

[0102] In another specific embodiment, referring to FIG15 , the Y-axis acceleration detection structure 10 includes a second mass 101 and a second capacitor group. The second mass 101 is secured to a substrate on either side by second torsion springs 103. Second mounting slots 104 are spaced apart in the middle of the second mass 101, distributed along the X-axis. Each second mounting slot 104 houses a second capacitor group. The second capacitor group includes a second positive fixed electrode 1021 and a second negative fixed electrode 1022, which are distributed along the X-axis direction. The middle portion of the second positive fixed electrode 1021 on the side close to the second negative fixed electrode 1022 is anchored to the substrate, and the middle portion of the second negative fixed electrode 1022 on the side close to the second positive fixed electrode 1021 is anchored to the substrate. The side of the second positive fixed electrode 1021 away from the second negative fixed electrode 1022 forms a third differential detection capacitor with the second mass block 101, and the side of the second negative fixed electrode 1022 away from the second positive fixed electrode 1021 forms a fourth differential detection capacitor with the second mass block 101.

[0103] When the second mass block 101 is displaced upward by the acceleration along the Y-axis, the capacitance spacing of the third differential detection capacitor decreases, and the capacitance spacing of the fourth differential detection capacitor increases. The capacitance difference between the third differential detection capacitor and the fourth differential detection capacitor changes in proportion to the acceleration along the Y-axis. By detecting the change in the capacitance difference, the real-time value of the acceleration along the Y-axis can be obtained.

[0104] Similarly, when the second mass 101 is displaced downward by the acceleration along the Y-axis, the real-time value of the acceleration along the Y-axis can also be obtained by detecting the change in the capacitance difference.

[0105] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An acceleration sensor, characterized in that, Comprising: A base, an anchor point, and an inner support unit, wherein the middle part of the inner support unit is fixed to the base through the anchor point; the inner support unit includes a first end and a second end; A first seesaw unit and a second seesaw unit, the first seesaw unit is elastically connected to the outside of the first end of the inner support unit, and the second seesaw unit is elastically connected to the outside of the second end of the inner support unit; the first seesaw unit and the second seesaw unit are arranged oppositely, and the first seesaw unit and the second seesaw unit are symmetrically distributed along the symmetry axis of the acceleration sensor respectively; the first seesaw unit forms two first seesaw structures on both sides of the symmetry axis respectively, and both of the two first seesaw structures rotate along a first rotating shaft; the second seesaw unit forms two second seesaw structures on both sides of the symmetry axis respectively, and both of the two second seesaw structures rotate along a second rotating shaft; the first rotating shaft and the second rotating shaft are arranged in parallel, and the symmetry axis is perpendicular to the first rotating shaft or the second rotating shaft; An out-of-plane displacement detection unit, and the out-of-plane displacement detection unit is arranged on both the first seesaw unit and the second seesaw unit.

2. The acceleration sensor according to claim 1, characterized in that, A first groove is arranged on the outside of the first seesaw unit, and a second groove is arranged on the inside of the second seesaw unit. Part of the first seesaw unit is embedded in the second groove and part of the second seesaw unit is embedded in the first groove to form a nested structure, and the nested structure is located between the first rotating shaft and the second rotating shaft.

3. The acceleration sensor according to claim 2, characterized in that, Further comprising a first detection mass block and a second detection mass block; Each of the first seesaw structures includes a first sub-rotating part and a second sub-rotating part, the first sub-rotating part and the second sub-rotating part are respectively located on opposite sides of the first rotating shaft, and a first groove is arranged on the outside of the second sub-rotating part; each of the second seesaw structures includes a third sub-rotating part and a fourth sub-rotating part, the third sub-rotating part and the fourth sub-rotating part are respectively located on opposite sides of the second rotating shaft, and a second groove is arranged on the inside of the third sub-rotating part; The first detection mass block is located on the first sub-rotating part, the second detection mass block is located on the fourth sub-rotating part, and the first detection mass block and the second detection mass block are symmetrically arranged.

4. The acceleration sensor according to claim 2, characterized in that, Further comprising a coupling beam, the coupling beam extends in a direction perpendicular to the symmetry axis, and one end of the coupling beam is connected to the second sub-rotating part and the other end is connected to the third sub-rotating part.

5. The acceleration sensor according to claim 1, characterized in that, Further comprising a first elastic member and a second elastic member, the first seesaw unit is connected to the first end of the inner support unit through the first elastic member; the second seesaw unit is connected to the second end of the inner support unit through the second elastic member; The first elastic member is close to the first rotating shaft and extends in a direction parallel to the first rotating shaft; the second elastic member is close to the second rotating shaft and extends in a direction parallel to the second rotating shaft.

6. The acceleration sensor according to claim 1, wherein The out-of-plane displacement detection unit is located in the area of the first seesaw unit far from the first rotating shaft; The out-of-plane displacement detection unit is located in the area of the second seesaw unit far from the second rotating shaft.

7. The acceleration sensor according to claim 1, characterized in that The two inner support units are symmetrically distributed along the symmetry axis; each inner support unit is fixed to the base through an anchor point, and the anchor point is located inside the inner support unit.

8. The acceleration sensor according to claim 1, characterized in that, The two inner support units are symmetrically distributed along the symmetry axis, and the middle parts of the two inner support units are connected, and an anchor point is located at the connection of the two inner support units.

9. The acceleration sensor according to any one of claims 7 or 8, characterized in that, It further includes an X-axis acceleration detection structure for detecting the acceleration in the X-axis direction; The X-axis acceleration detection structure is located between the two inner support units and is symmetrically distributed along the symmetry axis.

10. The acceleration sensor according to any one of claims 7 or 8, characterized in that, It further includes a Y-axis acceleration detection structure for detecting the acceleration in the Y-axis direction; The Y-axis acceleration detection structure is located between the two inner support units and is symmetrically distributed along the symmetry axis.

11. The acceleration sensor according to any one of claims 7 or 8, characterized in that, It further includes an X-axis acceleration detection structure and a Y-axis acceleration detection structure, the X-axis acceleration detection structure is used to detect the acceleration in the X-axis direction; the Y-axis acceleration detection structure is used to detect the acceleration in the Y-axis direction; Both the X-axis acceleration detection structure and the Y-axis acceleration detection structure are located between the two inner support units, and the X-axis acceleration detection structure and the Y-axis acceleration detection structure are respectively located on opposite sides of the anchor point.

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