An accelerometer

Abstract

The utility model discloses an accelerometer belongs to acceleration measurement technical field, and the accelerometer includes: outer frame and mass block, and the outer frame is connected in substrate, and the substrate is equipped with fixed anchor point, and the mass block is located the inside of outer frame and is elastically connected to fixed anchor point with substrate through elastic part, and the mass block can move along the acceleration direction to be measured, and the mass block is suitable for along the first axis symmetry and along the second axis asymmetry, and the first axis extends along the first direction, and the second axis extends along the second direction, one of mass block and outer frame is equipped with stopper, and the interval between the other of mass block and outer frame and stopper is less than the interval between the mass block and outer frame of the area outside stopper. The utility model embodiment adopts and sets up stopper in one of mass block and outer frame, thereby reduces the relative area of the close part between mass block and outer frame, reduces the electrostatic attraction, reduces the deviation distance simultaneously, and then improves the accuracy of accelerometer measurement acceleration.

Description

Technical Field

[0001] This utility model relates to the field of acceleration measurement technology, and in particular to an accelerometer. Background Technology

[0002] A capacitive accelerometer is a sensor that measures acceleration by utilizing changes in capacitance. Its working principle is based on the relationship between changes in capacitance and physical displacement. When the accelerometer is subjected to acceleration, the mass block moves due to inertial force, and the movable electrode inside will be displaced relative to the fixed electrode. This displacement change is then converted into a capacitance change. This change is processed by the back-end circuitry to calculate the magnitude and direction of the acceleration.

[0003] The existing accelerometer has an outer frame around the mass block. The outer frame and cover plate can protect the mass block and prevent the mass block from changing position too much when the impact force is too large. However, when the mass block moves, static electricity will be generated between it and the outer frame, causing the mass block to shift or be attracted by the large electrostatic attraction force and unable to move normally. Utility Model Content

[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes an accelerometer in which a stop block is installed on one of the mass block and the outer frame. When the stop block is installed on the mass block, the distance between the stop block and the outer frame is smaller than the distance between the mass block and the outer frame at other locations outside the stop block. This reduces the relative area of ​​the close-proximity portions between the mass block and the outer frame, reduces electrostatic attraction, and simultaneously reduces the offset of the mass block, thereby improving the accuracy of the accelerometer in measuring acceleration.

[0005] An accelerometer according to an embodiment of the present invention includes: an outer frame and a mass block; the outer frame is connected to a substrate, and the substrate is provided with a fixed anchor point; the mass block is disposed inside the outer frame and is elastically connected to the fixed anchor point via an elastic element to connect with the substrate, the mass block is movable along the direction of the acceleration to be measured, and the mass block is adapted to be symmetrical along a first axis and asymmetrical along a second axis, the first axis extending along a first direction and the second axis extending along a second direction; wherein, one of the mass block and the outer frame is provided with a stop block, and the distance between the other mass block and the stop block is smaller than the distance between the mass block and the outer frame outside the stop block.

[0006] According to the accelerometer of this utility model embodiment, when a force in the direction of acceleration is applied to the mass block, displacement will occur between the mass block and the fixed electrode located on the liner, thereby affecting the capacitance between the mass block and the fixed electrode. The acceleration is calculated by processing the change in capacitance. The mass block is placed inside the outer frame, and the outer frame protects the mass block to prevent large displacement caused by impact, which could damage the accelerometer. A large electrostatic attraction force is generated between the outer frame and the mass block. Therefore, a stop block is set outside the mass block. The distance between the stop block and the outer frame is smaller than the distance between the area of ​​the mass block outside the stop block and the outer frame. When the stop block is not present, the electrostatic attraction area during mass block movement is the relative area between the entire side of the mass block and the outer frame. When the stop block is present, the electrostatic attraction area is the relative area between the stop block and the outer frame, which is smaller. This reduces the electrostatic attraction force between the mass block and the outer frame, preventing the attraction force from becoming too large and exceeding the mechanical restoring force of the device, thus preventing the mass block from returning to its initial position and causing device failure.

[0007] Furthermore, by setting the mass block to be symmetrical in one direction and asymmetrical in the other, when the mass block is subjected to a force along the direction of the acceleration to be measured, the mass block can have eccentric mass on both sides of the second axis and can rotate, thereby changing the distance between the mass block and the fixed electrode on the substrate. As a result, the capacitance between the mass block and the fixed electrode changes, and the magnitude of the applied acceleration can be calculated by the change in capacitance. Moreover, the symmetry of the mass block on both sides of the first axis can reduce the problem of mass block offset.

[0008] According to the accelerometer of this utility model embodiment, one of the mass block and the outer frame is provided with the stop block and the other is provided with a groove, the groove and the stop block are engaged and have a gap.

[0009] According to an embodiment of the present invention, the accelerometer unit includes a first body part and a second body part. The two second body parts are connected to the two ends of the first body part along a second direction, and the second body parts extend along a first direction. The fixed anchor point is located between the two second body parts. The elastic member is connected between each second body part and the fixed anchor point. The two second body parts and the surface of the first body part facing the outer frame are provided with the stop block. The outer frame is provided with the groove corresponding to the stop block.

[0010] According to an embodiment of the present invention, the accelerometer includes a first body portion and a second body portion; the second body portion extends along a first direction and the first body portion extends along a second direction, one end of the second body portion is connected to the middle position of the first body portion along the second direction, the second body portion is provided with fixed anchor points on both sides along the second direction, the elastic element is provided between the fixed anchor point on each side and the second body portion, the first body portion is provided with a stop block on the surface facing the outer frame, and the outer frame is provided with a groove at the corresponding position of the stop block.

[0011] The accelerometer according to an embodiment of the present invention further includes a compensation structure and a connecting rod, one end of the connecting rod being connected to the fixed anchor point and the other end being connected to the compensation structure, and the compensation structure and the mass block being connected by the elastic element.

[0012] According to the accelerometer of this utility model embodiment, there is at least one mass block. When there are two mass blocks, the two mass blocks are opposite each other along a first direction, and each of the two mass blocks is provided with a fixed anchor point on both sides along a second direction. Each mass block is elastically connected to the fixed anchor point on the corresponding side along both sides of the second direction.

[0013] According to the accelerometer of this utility model embodiment, one of the two mass blocks is provided with the groove and the other is provided with the stop block, so that the stop block is opposite to the groove.

[0014] According to the accelerometer of this utility model embodiment, an intermediate fixed anchor point is selectively provided between the two mass blocks, one of the mass blocks and the intermediate fixed anchor point is provided with a groove and the other is provided with the stop block.

[0015] According to the accelerometer of this embodiment, two mass blocks are distributed along a second direction, each mass block is elastically connected to a corresponding fixed anchor point, and the two mass blocks are separated by an intermediate fixed anchor point. Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of the mass block and the outer frame of this utility model, which shows that the contact area is small and contact occurs due to the setting of the stop block; Figure 2This is a schematic diagram of the structure of the mass block of this utility model, in which stop blocks are provided in different directions facing the outer frame; Figure 3 This is a schematic diagram of the structure of the stop blocks and the outer frame attracting each other in different directions of the mass block according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the fit between the stop block and the groove in the outer frame according to an embodiment of the present utility model. Figure 5 This is a schematic diagram of the structure of the stop block and the groove in the mass block according to an embodiment of the present utility model; Figure 6 This is a schematic diagram of the structure of the mass block, elastic element, and fixed anchor point when the mass block is n-shaped according to an embodiment of the present invention; Figure 7 This is a schematic diagram showing the connection relationship between the mass block, the connecting rod, the compensation structure, the elastic element, and the fixed anchor point when the mass block is n-shaped according to an embodiment of this utility model. Figure 8 This is a schematic diagram of the connection between the mass block, the elastic element, and the fixed anchor point when the mass block is T-shaped according to an embodiment of the present invention. Figure 9 This is a schematic diagram showing the connection relationship between the mass block, the elastic element, the compensation structure, and the connecting rod when the mass block in this embodiment of the utility model is T-shaped. Figure 10 This is a schematic diagram of the connection between the anchor point structure of this utility model and the elastic element when the two anchor points are combined. Figure 11 This is a schematic diagram of the connection between the anchor point structure and the elastic element when the anchor point structure of this utility model has four points; Figure 12 This is a schematic diagram of an embodiment of the present invention, showing the combination of two n-shaped mass blocks and their connection with an elastic element, an anchor point structure, and a compensation structure. Figure 13 This is a schematic diagram of an embodiment of the present invention, showing the combination of two T-shaped mass blocks and their connection with an elastic element, an anchor point structure, and a compensation structure. Figure 14 This is a schematic diagram of another embodiment of the present invention, showing the combination of two T-shaped mass blocks and their connection with the elastic element, anchor point structure, and compensation structure. Figure 15 This is a schematic diagram of another embodiment of the present invention, showing the combination of two n-shaped mass blocks and their connection with the elastic element, anchor point structure, and compensation structure.

[0017] Figure label: Mass block 1, large area 11, stop block 12, first body part 13, second body part 14, fixed anchor point 2, elastic element 3, outer frame 4, groove 41, first stop surface 411, second stop surface 412, third stop surface 413, connecting rod 5, compensation structure 6, intermediate fixed anchor point 7, second axis 8, first axis 9. Detailed Implementation

[0018] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0019] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0020] The following is for reference. Figures 1-15The accelerometer according to an embodiment of the present invention employs a stop block 12 in one of the mass block 1 and the outer frame 4. When the stop block 12 is set in the mass block 1, the distance between the stop block 12 and the outer frame 4 is less than the distance between the mass block 1 and the outer frame 4 at other positions outside the stop block 12. This reduces the relative area of ​​the close portion between the mass block 1 and the outer frame 4, reduces the electrostatic attraction force, and prevents the attraction force from being too large and exceeding the mechanical restoring force of the device, which would prevent the mass block 1 from returning to its initial position and cause device failure. At the same time, it reduces the offset problem of the mass block 1, thereby improving the accuracy of the accelerometer in measuring acceleration.

[0021] like Figure 1-15 As shown, an accelerometer according to an embodiment of the present invention includes: an outer frame 4 and a mass block 1. The outer frame 4 is connected to a substrate, and the substrate is provided with a fixed anchor point 2. The mass block 1 is disposed inside the outer frame 4 and is elastically connected to the fixed anchor point 2 via an elastic member 3 to connect with the substrate. The mass block 1 is movable along the direction of the acceleration to be measured. The mass block 1 is adapted to be symmetrical along a first axis 9 and asymmetrical along a second axis 8. The first axis 9 extends along a first direction, and the second axis 8 extends along a second direction. Among them, one of the mass block 1 and the outer frame 4 is provided with a stop block 12, and the distance between the other mass block 1 and the stop block 12 is smaller than the distance between the mass block 1 and the outer frame 4 outside the stop block 12.

[0022] In practice, the accelerometer includes a substrate with fixed electrodes. A mass block 1 is elastically connected to the substrate via an elastic element 3, which is a spring. An outer frame 4 is connected to the substrate. For example, the fixed electrodes are positioned along the mass block 1... Figure 1 When referring to the rear side, the rear side means along the Figure 1 The direction perpendicular to the paper and facing inwards, that is, along the distance between the fixed electrode and mass block 1. Figure 1 The inward and outward directions are relative, where "inward" refers to the direction perpendicular to the paper and facing inwards, and "outward" refers to the direction perpendicular to the paper and facing outwards. If the direction of the acceleration being measured is also the inward and outward direction, then... Figure 1 When mass block 1 accelerates in the direction from the inside out, because mass block 1 is symmetrical along the first axis 9 and asymmetrical along the second axis 8, that is, mass block 1 has an eccentric mass design along the second axis 8, when a force is applied to mass block 1 outward along the inner side of mass block 1, mass block 1 will rotate relative to the second axis 8, that is, the second axis 8 is the axis of rotation. After mass block 1 rotates, the distance between it and the fixed electrode of the substrate changes. The change in distance causes a change in capacitance between mass block 1 and the fixed electrode. After a series of processing by the subsequent circuit, the magnitude of the input acceleration can be calculated.

[0023] Specifically, such as Figure 6As shown, the mass block 1 above the second axis 8 has a larger mass, while the part below the second axis 8 has a smaller mass. Therefore, when there is acceleration in the inward and outward directions, the part of the mass block 1 above the second axis 8 rotates in the direction of the acceleration to be measured, and the part of the mass block 1 below the second axis 8 rotates in the opposite direction of the acceleration to be measured, thereby changing the distance between the mass block 1 and the fixed electrode. The change in distance causes a change in capacitance. The subsequent circuit processes the changed capacitance to obtain the magnitude and direction of the acceleration.

[0024] When mass block 1 is asymmetrical along the first axis 9, as mass block 1 rotates, one side will be closer to the outer frame 4 due to the asymmetry along the first axis 9, causing structural offset. This alters the area of ​​mass block 1 facing the fixed electrode, resulting in numerous variables affecting capacitance. Consequently, the accuracy of measuring acceleration along the inward and outward directions decreases. Therefore, symmetrically positioning mass block 1 along the first axis 9 prevents this asymmetry during rotation. Figure 6 The left and right offset reduces the impact of the offset on the capacitance between the mass block 1 and the fixed electrode, thereby improving the accuracy of acceleration measurement.

[0025] in addition, Figure 1 The outer frame 4 in the diagram is for illustrative purposes only, showing only a portion of it. One side of the mass block 1 faces the substrate, while the other sides are surrounded by the outer frame 4. The outer frame 4 surrounds the outer perimeter of the mass block 1, protecting it and preventing large displacements that could cause accelerometer malfunction when the mass block 1 is subjected to impact. However, the relative area between the mass block 1 and the outer frame 4 is relatively large. When the mass block 1 is subjected to a force in the direction of the acceleration to be measured, electrostatic adsorption occurs between the mass block 1 and the outer frame 4. Due to the large relative area, if the electrostatic adsorption force exceeds the mechanical restoring force of the mass block 1, the mass block 1 and the outer frame 4 will become stuck together and unable to return to their original position, leading to device failure.

[0026] Therefore, in this embodiment of the invention, a stop block 12 can be provided on the outer wall of the mass block 1 at a position close to the outer frame 4. When the mass block 1 moves, the gap between the stop block 12 and the outer frame 4 is smaller than the gap between other positions of the mass block 1 and the outer frame 4. Figure 1 The distance between the stop block 12 and the outer frame 4 is smaller than the distance between the large area 11 and the outer frame 4. When the mass block 1 moves, the stop block 12 will contact the outer frame 4 first. The electrostatic adsorption area is the side of the stop block 12. Since the side area of ​​the stop block 12 is much smaller than the side area of ​​the entire mass block 1 on the side close to the outer frame 4, the electrostatic adsorption force can be effectively reduced, preventing the problem of adsorption failure.

[0027] Of course, in actual design, the stop block 12 can also be designed on the surface of the outer frame 4 that is close to the mass block 1. This can also make the distance between the stop block 12 and the mass block 1 smaller than the distance between the outer frame 4 and the mass block 1 outside the stop block 12. When the mass block 1 moves under the action of acceleration force, the electrostatic adsorption force between the area of ​​the outer frame 4 outside the stop block 12 and the mass block 1 is reduced, preventing device failure.

[0028] In some embodiments, one of the mass block 1 and the outer frame 4 is provided with a stop block 12 and the other is provided with a groove 41, the groove 41 and the stop block 12 are engaged and have a gap.

[0029] like Figure 1 As shown, when the mass block 1 is provided with a stop block 12 on the side facing the outer frame 4, the outer frame 4 is provided with a groove 41 at the position opposite to the stop block 12. When the mass block 1 is subjected to a force in the direction of the acceleration to be measured, the position of the stop block 12 may be attracted to the groove 41. However, since the contact area here is small, the electrostatic attraction force is small and less than the mechanical restoring force of the spring. Therefore, the mass block 1 and the outer frame 4 will not be attracted. Thus, when the mass block 1 is subjected to a force in the direction of the acceleration to be measured, it can still rotate normally around the second axis 8, thereby measuring the change in the distance between the mass block 1 and the fixed electrode caused by the acceleration, and calculating the acceleration through the distance change.

[0030] By providing a groove 41 at the position opposite to the stop block 12, the mass block 1 can rotate within a controllable range, reducing the distance between the mass block 1 and the stop block 1. Figure 1 The amplitude of movement in the extension direction of the second axis 8, such as Figure 3 The groove 41 is provided with a first stop surface 411, a second stop surface 412, and a third stop surface 413. When the mass block 1 moves and comes into contact with the outer frame 4, the electrostatic attraction force is very small, so no attraction occurs. Therefore, when the mass block 1 is subjected to acceleration in the inward and outward directions, it does not affect the inward and outward rotation of the mass block 1 along the second axis 8, and also reduces the degree of vertical displacement of the mass block 1. When it is displaced vertically, the relative area between the mass block 1 and the fixed electrode also changes. That is, both variables can cause changes in capacitance. Therefore, when measuring acceleration in the inward and outward directions, the accuracy of acceleration measurement is reduced. In other words, the design of the stop block 12 and the groove 41 not only reduces electrostatic attraction, but also prevents the mass block 1 from displacing too much in other directions, thus improving the accuracy of acceleration measurement.

[0031] In some embodiments, the mass block 1 includes a first body portion 13 and a second body portion 14. The two second body portions 14 are connected to the two ends of the first body portion 13 along a second direction, and the second body portions 14 extend along a first direction. The fixed anchor point 2 is located between the two second body portions 14. An elastic member 3 is connected between each second body portion 14 and the fixed anchor point 2. The two second body portions 14 and the surface of the first body portion 13 facing the outer frame 4 are provided with a stop block 12. The outer frame 4 is provided with a groove 41 corresponding to the stop block 12.

[0032] Combination Figure 2 , Figure 3 and Figure 6 As shown, the mass block 1 is constructed in an n-shape. This n-shape structure includes a first body portion 13 extending laterally and two second body portions 14 at both ends of the first body portion 13 along a second direction. The second direction is the direction in which the second axis 8 extends. Therefore, the mass block 1 can be asymmetrical only along the second axis 8 and symmetrical along the first axis 9 extending in the first direction. Figures 2-6 The vertical direction allows the mass block 1 to exert a force along the direction of the acceleration to be measured. By rotating it along the second axis 8, the distance between it and the fixed electrode can be changed, thus improving the accuracy of acceleration measurement.

[0033] Furthermore, stop blocks 12 are provided on the side of the first body part 13 and the two second body parts 14 facing the outer frame 4, and grooves 41 are provided at the corresponding positions of the outer frame 4. Since the first body part 13 and the two second body parts 14 are provided with stop blocks 12, when the mass block 1 moves and comes into contact with the outer frame 4, the contact area between each surface of the mass block 1 facing the outer frame 4 and the outer frame 4 is small, which reduces the electrostatic adsorption force of the mass block 1 in all directions.

[0034] In some embodiments, refer to Figure 8 and Figure 9 As shown, the mass block 1 includes a first body part 13 and a second body part 14; the second body part 14 extends along a first direction and the first body part 13 extends along a second direction. One end of the second body part 14 is connected to the middle position of the first body part 13 along the second direction. Fixed anchor points 2 are provided on both sides of the second body part 14 along the second direction. An elastic member 3 is provided between the fixed anchor point 2 on each side and the second body part 14. A stop block 12 is provided on the surface of the first body part 13 facing the outer frame 4. A groove 41 is provided at the corresponding position of the outer frame 4 and the stop block 12.

[0035] At this time, the mass block 1 is constructed in a T-shape. The first body part 13 is connected to the second body part 14 at the middle position in the second direction. The T-shape is asymmetrical relative to the second axis 8. Therefore, the mass block 1, which is asymmetrical along the second axis 8, can rotate along the second axis 8 when subjected to acceleration in the internal and external directions. Furthermore, the mass block 1 is also symmetrical along the first axis 9, which reduces the offset problem of the mass block 1. The first direction is the extension direction of the first axis 9, and the second direction is the extension direction of the second axis 8. At this time, the second body part 14 of the T-shaped mass block 1 is provided with a fixed anchor point 2 on both sides along the second direction, which is... Figure 8 In the left and right directions, both sides of the second body part 14 are elastically connected to a fixed anchor point 2 through an elastic element 3. The elastic element 3 is a spring. When the T-shaped structure is subjected to a force along the direction of the acceleration to be measured, the T-shaped mass block 1 can rotate relative to the second axis 8, thereby changing the capacitance between the mass block 1 and the fixed electrode, which makes it easier to measure the acceleration later.

[0036] Furthermore, at this time, the first body part 13 and the second body part 14 of the T-shaped mass block 1 are both provided with stop blocks 12 on the side facing the outer frame 4. Through the design of the stop blocks 12, the electrostatic adsorption area between the mass block 1 and the outer frame 4 can be reduced, thereby reducing the electrostatic adsorption force. It can also accurately measure the change in capacitance based on the change in distance between the mass block 1 and the fixed electrode when the mass block 1 is subjected to the force of acceleration in the inward and outward directions, and calculate the acceleration based on the change in capacitance.

[0037] Furthermore, the lower part of the first body part 13 of the T-shaped structure can be uniformly designed with multiple stop blocks 12 distributed along the second direction, and the two sides of the first body part 13 along the second direction are also provided with stop blocks 12, which improves the balance between the stop blocks 12 and the outer frame 4 when subjected to electrostatic adsorption force, reduces the problem of deflection in other directions other than the second axis 8, and thus improves the accuracy of acceleration measurement.

[0038] In some embodiments, the accelerometer further includes a compensation structure 6 and a connecting rod 5, one end of the connecting rod 5 being connected to a fixed anchor point 2 and the other end being connected to the compensation structure 6, and the compensation structure 6 and the mass block 1 being connected by an elastic member 3.

[0039] In practice, refer to Figure 7 As shown, taking the mass block 1 as an example of an n-shape, the connecting rod 5 is a rigid connecting rod with high stiffness. It can be allowed to rotate in the plane and produce limited deformation, but it has more obvious torsional deformation. The displacement of the compensation structure 6 to the outside plane can compensate for deviations caused by factors such as temperature and process errors.

[0040] Specifically, after mass block 1 is installed, before it is subjected to the force in the direction of the acceleration to be measured, there may be a misalignment between the relative surfaces of mass block 1 and the fixed electrode due to temperature or encapsulation stress. Therefore, a compensation structure 6 is installed. The compensation structure 6 and the fixed anchor point 2 are connected by a rigid connecting rod 5. The connecting rod 5 and the spring are parallel. The misalignment of the compensation structure 6 and the connecting rod 5 in the inward and outward directions is much smaller than that of the spring. The compensation structure 6 can compensate for the influence of the distance between mass block 1 and the fixed electrode due to temperature or encapsulation stress. In other words, the measured distance change is as close as possible to the change caused by acceleration, rather than the change caused by temperature or encapsulation error. Therefore, the final measured acceleration is more accurate.

[0041] Furthermore, the stiffness of the rigid connecting rod 5 is much greater than that of the spring. Therefore, when there is an acceleration input along the detection axis, the resulting torsion is much smaller than that generated by the spring. The out-of-plane displacement generated by the compensation structure 6 is also much smaller than that generated by the mass block 1. In other words, the compensation structure 6 is almost unaffected by acceleration. Thus, the offset generated by the compensation structure 6 represents the offset introduced by temperature and other influencing factors. This allows the compensation structure 6 to compensate for errors in temperature or encapsulation stress, thereby improving the accuracy of acceleration measurement. In this embodiment of the present invention, the acceleration along the detection axis is in the direction perpendicular to the paper plane and towards the inside and outside as shown in the figure.

[0042] In some embodiments, there is at least one mass block 1. When there are two mass blocks 1, both mass blocks 1 are arranged around the outside of the fixed anchor point 2 and are opposite each other along the first direction. The fixed anchor point 2 is elastically connected to the mass blocks 1 on both sides along the second direction.

[0043] In practice, one mass block 1 can be set within an accelerometer, or multiple mass blocks 1 can be set. Taking two mass blocks 1 as an example, for instance... Figure 12 As shown, two n-shaped mass blocks 1 are opposite each other along a first direction. When each n-shaped mass block 1 is subjected to forces in the inner and outer directions, it can rotate along a second axis 8 extending in a second direction. At this time, a fixed anchor point 2 is set between the two second body parts 14 of each n-shaped mass block 1. An elastic element 3, a compensation structure 6, and a connecting rod 5 are connected between the fixed anchor point 2 and each second body part 14. For example, each mass block 1 corresponds to two connecting rods 5, two elastic elements 3, and two compensation structures 6. The two connecting rods 5 corresponding to each mass block 1 are connected to the two sides of a fixed anchor point 2 along the second direction. Each connecting rod 5 is connected to a compensation structure 6. Each compensation structure 6 is connected to the corresponding second body part 14 by an elastic element 3. That is, two n-shaped mass blocks 1 can be elastically connected through a fixed anchor point 2, which improves the integration of the structure. The functions of the compensation structure 6 and the elastic element 3 are the same as those described above.

[0044] Of course, it is also possible to Figure 12 One of the fixed anchor points 2 is split into a combination of multiple fixed anchor points 2, which can realize the elastic connection between the second body part 14 of the n-shaped mass block 1 and the fixed anchor point 2. For example, the second body part 14 and the fixed anchor point 2 are directly connected to the elastic element 3, or the fixed anchor point 2 and the second body part 14 are sequentially connected by the aforementioned connecting rod 5, compensation structure 6 and elastic element 3.

[0045] When two mass blocks 1 are simultaneously subjected to acceleration in the inward and outward directions, each n-shaped mass block 1 can rotate relative to the corresponding second axis 8, and each mass block 1 corresponds to a fixed electrode. The distance between the two mass blocks 1 and the corresponding fixed electrodes changes, which causes the capacitance between the two mass blocks 1 and the two corresponding fixed electrodes to also change. The corresponding acceleration can be calculated by the change in capacitance. In other words, by setting up two mass blocks 1 and two corresponding fixed electrodes, the accuracy of measuring the same acceleration is improved.

[0046] In some embodiments, there is at least one mass block 1. When there are two mass blocks 1, the two mass blocks 1 are opposite each other along the first direction, and each of the two mass blocks 1 is provided with a fixed anchor point 2 on both sides along the second direction. Each mass block 1 is elastically connected to the fixed anchor point 2 on the corresponding side along both sides of the second direction.

[0047] At this time, the mass block 1 has two T-shaped structures. The two T-shaped mass blocks 1 are provided with two fixed anchor points 2 on each side along the second direction. For example, the second body part 14 of each T-shaped mass block 1 is connected to one fixed anchor point 2 along one side of the second direction through a set of elastic elements 3, compensation structure 6 and connecting rod 5. The second body part 14 along the other side of the second direction is connected to another fixed anchor point 2 through another set of elastic elements 3, compensation structure 6 and connecting rod 5. Each T-shaped mass block 1 can rotate relative to the corresponding second axis 8. The second body part 14 of the two mass blocks 1 can share one fixed anchor point 2 on each side along the second direction, which improves the integration of the structure, saves the number of fixed anchor points 2, simplifies the installation steps, reduces the cost, and also reduces the area occupied by the accelerometer.

[0048] In some embodiments, one of the two mass blocks 1 is provided with a groove 41 and the other is provided with a stop block 12, such that the stop block 12 is opposite to the groove 41.

[0049] In other words, a stop block 12 can be set on one of the two mass blocks 1 at their opposite positions, and a groove 41 can be set on the other, thereby reducing the attraction force between the two mass blocks 1. This can prevent the attraction force from being too large and affecting the movement of the mass block 1. For example, it can prevent the attraction force from being too large and exceeding the mechanical restoring force of the device, which would prevent the mass block from returning to its initial position and cause the device to fail.

[0050] In some embodiments, an intermediate fixing anchor point 7 is selectively provided between the two mass blocks 1, one of the mass blocks 1 and the intermediate fixing anchor point 7 is provided with a groove 41 and the other is provided with a stop block 12.

[0051] Specifically, refer to Figure 14 As shown, the mass blocks 1 at this time are also two T-shaped mass blocks 1. In addition to the two fixed anchor points 2 respectively set on both sides of the second direction of the second body part 14, the two mass blocks 1 are also provided with a middle fixed anchor point 7 between them to reduce the contact between the two mass blocks 1. Moreover, due to the presence of the stop block 12, there will be slight differences in the structure of the mass blocks 1 on both sides. Therefore, a middle fixed anchor point 7 is set between the two mass blocks 1, so that a stop block 12 is set on the side of each mass block 1 facing the middle fixed anchor point 7. The middle fixed anchor point 7 and the stop block 12 are provided with a groove 41 at the corresponding positions, thereby keeping the structure of the two mass blocks 1 completely the same. This can avoid the difference in displacement change after rotation caused by the difference in the structure of the two mass blocks 1, thereby reducing the measurement error of acceleration caused by the difference in structure when measuring the acceleration of the two mass blocks 1, and further improving the accuracy of acceleration measurement.

[0052] In some embodiments, there is at least one mass block 1. When there are two mass blocks 1, the two mass blocks 1 are distributed along the second direction. Each mass block 1 is elastically connected to a corresponding fixed anchor point 2. The two mass blocks 1 are also separated by an intermediate fixed anchor point 7.

[0053] Specifically, refer to Figure 15As shown, the mass blocks 1 at this time are two n-shaped mass blocks 1 with opposite openings, and the two mass blocks 1 are distributed along the second direction. A fixed anchor point 2 is provided between the two second body parts 14 of each n-shaped mass block 1. This fixed anchor point 2 can be one or more. Two connecting rods 5 are respectively connected to the two second body parts 14 facing one of the mass blocks 1. Each connecting rod 5 is connected to a compensation structure 6, and an elastic element 3 is connected through the compensation structure 6. The elastic element 3 is connected to the second body part 14. Simultaneously, an intermediate fixed anchor point 7 is provided between the two n-shaped structures to reduce the mutual influence between the two mass blocks 1. Therefore, by setting two mass blocks 1 and separating them through the intermediate fixed anchor point 7, the difference in displacement changes after rotation caused by the different structures of the two mass blocks 1 can be avoided, thereby reducing the measurement error problem of acceleration caused by the different structures of the two mass blocks 1 when measuring acceleration, and further improving the accuracy of acceleration measurement. Similarly, a groove 41 can be provided in one of the fixed anchor point 7 in the middle and the mass block 1 on the corresponding side, and a stop block 12 can be provided in the other. Of course, stop blocks 12 can also be provided in the fixed anchor point 7 in the middle and the mass blocks 1 on both sides, and the corresponding mass blocks 1 do not need to be provided with grooves 41, which can reduce electrostatic adsorption force.

[0054] Moreover, refer to Figure 14 and 15 As shown, a stop block 12 can also be installed on the compensation structure 6, opposite to the mass block 1, the outer frame 4, the fixed anchor point 2, or the intermediate fixed anchor point 7. In this case, the stop block 12 can also reduce the electrostatic attraction force between itself and the mass block 1, improving the accuracy of the measured acceleration. Furthermore, when the stop block 12 is installed on the compensation structure 6, Figure 14 and Figure 15 This only shows a portion of the stop blocks 12; multiple blocks can be set according to the actual situation, but this will not be elaborated here.

[0055] Additionally, it should be noted that, referring to Figure 10 and Figure 11 As shown, when the compensation structure 6 and connecting rod 5 are not provided, one end of the elastic element 3 can be connected to the mass block 1, and the other end is suitable for connecting multiple fixed anchor points 2. That is, multiple fixed anchor points 2 can be combined, and multiple springs can be provided to connect different fixed anchor points 2 respectively. Figure 10 There are two fixed anchor points 2, such as the two fixed anchor points 2 being set at intervals along the first direction, and the fixed anchor point 2 on each side being connected to the mass block 1 through the elastic element 3; Figure 11The four fixed anchor points 2 are divided into two groups. The two groups of fixed anchor points 2 are respectively located on both sides of the first direction, and the two fixed anchor points 2 on each side are connected to the mass block 1 through the elastic element 3. The two fixed anchor points 2 that are opposite each other in the first direction in the two groups of fixed anchor points 2 are also connected through the elastic element 3. Through this variable combination of fixed anchor points 2, it can be adjusted according to the convenience of actual installation, thereby improving the flexibility of structural installation.

[0056] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0057] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An accelerometer, characterized in that, include: Outer frame (4), the outer frame (4) is connected to the substrate, the substrate is provided with fixed anchor points (2); Mass block (1), the mass block (1) is disposed on the inner side of the outer frame (4) and is elastically connected to the fixed anchor point (2) by the elastic element (3) to be connected to the substrate. The mass block (1) is movable along the direction of the acceleration to be measured. The mass block (1) is adapted to be symmetrical along the first axis and asymmetrical along the second axis. The first axis extends along the first direction and the second axis extends along the second direction. One of the mass block (1) and the outer frame (4) is provided with a stop block (12), and the distance between the other mass block (1) and the stop block (12) is smaller than the distance between the mass block (1) and the outer frame (4) outside the stop block (12).

2. The accelerometer according to claim 1, characterized in that, One of the mass block (1) and the outer frame (4) is provided with the stop block (12) and the other is provided with a groove (41), the groove (41) and the stop block (12) are fitted together and have a gap.

3. The accelerometer according to claim 2, characterized in that, The mass block (1) includes a first body part (13) and a second body part (14), the two second body parts (14) are connected to the two ends of the first body part (13) along the second direction, and the second body parts (14) extend along the first direction; The fixed anchor point (2) is located between the two second body parts (14), and the elastic element (3) is connected between each second body part (14) and the fixed anchor point (2). The two second body parts (14) and the first body part (13) are provided with the stop block (12) on the surface facing the outer frame (4). The outer frame (4) is provided with the groove (41) corresponding to the stop block (12).

4. The accelerometer according to claim 2, characterized in that, The mass block (1) includes a first body part (13) and a second body part (14). The second body part (14) extends along the first direction and the first body part (13) extends along the second direction. One end of the second body part (14) is connected to the middle position of the first body part (13) along the second direction. The second body part (14) is provided with fixed anchor points (2) on both sides along the second direction. The elastic member (3) is provided between the fixed anchor point (2) on each side and the second body part (14). The first body part (13) is provided with a stop block (12) on the side facing the outer frame (4). The outer frame (4) is provided with a groove (41) at the corresponding position of the stop block (12).

5. The accelerometer according to claim 3 or 4, characterized in that, It also includes a compensation structure (6) and a connecting rod (5), one end of which is connected to the fixed anchor point (2) and the other end is connected to the compensation structure (6), and the compensation structure (6) and the mass block (1) are connected by the elastic element (3).

6. The accelerometer according to claim 3, characterized in that, There is at least one mass block (1). When there are two mass blocks (1), both mass blocks (1) are arranged around the outside of the fixed anchor point (2) and are opposite each other along the first direction. The fixed anchor point (2) is elastically connected to the mass blocks (1) on both sides along the second direction.

7. The accelerometer according to claim 4, characterized in that, There is at least one mass block (1). When there are two mass blocks (1), the two mass blocks (1) are opposite each other along the first direction, and each of the two mass blocks (1) is provided with a fixed anchor point (2) on both sides along the second direction. Each mass block (1) is elastically connected to the fixed anchor point (2) on the corresponding side along both sides of the second direction.

8. The accelerometer according to claim 6 or 7, characterized in that, One of the two mass blocks (1) is provided with the groove (41) and the other is provided with the stop block (12) so that the stop block (12) is opposite to the groove (41).

9. The accelerometer according to claim 7, characterized in that, An intermediate fixed anchor point (7) is selectively provided between the two mass blocks (1), one of the mass blocks (1) and the intermediate fixed anchor point (7) is provided with a groove (41) and the other is provided with the stop block (12).

10. The accelerometer according to claim 3, characterized in that, There is at least one mass block (1). When there are two mass blocks (1), the two mass blocks (1) are distributed along the second direction. Each mass block (1) is elastically connected to the corresponding fixed anchor point (2). The two mass blocks (1) are also separated by an intermediate fixed anchor point (7).

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