Dual axis shock resistant capacitive accelerometer sensor based on embedded prong stops and bump stops

Abstract

The application discloses a kind of double-axis impact-resistant capacitive accelerometer sensors based on embedded prong stop and anti-collision platform, and it is related to micro-electro-mechanical system manufacturing technical field.The movable mass block, first structural unit, second structural unit and anti-overload fixed anchor point area are included, the movable mass block is the whole block structure, and the anti-overload fixed anchor point area is located between the first structural unit and the second structural unit.The movable mass block is divided into upper, middle and lower three parts according to the position of the first structural unit, the anti-overload fixed anchor point area and the second structural unit, and the upper and lower parts of the movable mass block are the same and symmetrical.The first structural unit and the second structural unit both include a plurality of drive comb tooth anchor point areas, and each drive comb tooth anchor point area is provided with an anti-collision area and a comb tooth connection area at the part connected with the movable mass block, and the comb tooth connection area forms a corresponding variable gap sensitive differential capacitor.The part connected with the movable mass block of the anti-overload fixed anchor point area forms a plurality of anti-biaxial overload embedded prong stop areas.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of micro-electro-mechanical system (MEMS) manufacturing, in particular to a dual-axis anti-impact capacitive accelerometer sensor based on embedded fork tooth stop and anti-collision platform. BACKGROUND

[0002] MEMS acceleration micromechanical acceleration sensor has the advantages of small mass, low power consumption, easy digitization and intelligence, and is widely used in various fields. In recent years, the accelerometer has been developed, but has been hindered in many ways, which is reflected in the difficulty of the accelerometer to withstand the peak 30000g, the pulse width of about 8ms acceleration impact. This high overload harsh environment puts forward strict requirements on the anti-overload ability of the micromechanical acceleration sensor. At the same time, in order to realize the increase of accuracy, its low range working state also needs to meet the measurement accuracy requirements.

[0003] So far, in order to balance the contradiction between the increase of the stiffness of the sensitive structure of the meter head and the decrease of the detection precision in the small range, a variety of micro-capacitive accelerometers with overload protection devices have been proposed, but most of them cannot meet the requirements of accurate detection in the low range of 50g, while being compatible with the anti-axial peak 30000g, half-sine pulse width of about 8ms acceleration impact. SUMMARY

[0004] In order to overcome the shortcomings of the prior art and solve the problem of the accelerometer in the case of accurate detection in the low range, while being compatible with the anti-lateral and axial peak 30000g, half-sine pulse width of about 8ms acceleration impact, the present application provides a dual-axis anti-impact capacitive accelerometer sensor based on embedded fork tooth stop and anti-collision platform.

[0005] The application is realized by the technical scheme as follows: a dual-axis impact-resistant capacitive accelerometer sensor based on embedded prong stop and anti-collision platform, comprising a movable mass, a first structural unit, a second structural unit and an anti-overload fixed anchor point area, the movable mass is a whole structure, and the anti-overload fixed anchor point area is located between the first structural unit and the second structural unit; the movable mass is divided into upper, middle and lower parts according to the positions of the first structural unit, the anti-overload fixed anchor point area and the second structural unit, and the upper and lower parts of the movable mass are the same and symmetrical in structure, and the upper and lower parts of the movable mass are respectively left-right symmetrical. The movable mass has mass Y-axis comb teeth and mass X-axis comb teeth, which are respectively used for connecting driving Y-axis comb teeth and driving X-axis comb teeth, and form a plurality of comb tooth connection areas after connection. The first structural unit and the second structural unit both comprise a plurality of driving comb tooth anchor point areas, each driving comb tooth anchor point area is provided with an anti-collision area and a comb tooth connection area at the part connected with the movable mass, the comb tooth connection area forms a corresponding variable gap sensitive differential capacitor, the variable gap sensitive differential capacitor is divided into X direction and Y direction, and according to the direction of the variable gap sensitive differential capacitor, the acceleration in the X-axis and Y-axis directions can be measured. The part connected with the movable mass of the anti-overload fixed anchor point area forms a plurality of anti-dual-axis overload embedded prong stop areas. The center of the anti-overload fixed anchor point area is taken as the origin, left and right are taken as the X-axis, and the straight line of the X-axis is taken as the Y-axis, so that the sensor is symmetrical up and down along the X-axis and symmetrical left and right along the Y-axis, and cross coupling can be effectively eliminated.

[0006] Further, for the convenience of description, the upper part of the movable mass is described as being divided into structures by a transverse region. The structure of the upper part of the movable mass includes a transverse region, a rectangular window is opened in the middle part of the transverse region, and the left and right inner edges of the window are respectively connected with the same S-shaped folding beam fixed anchor point area through corresponding S-shaped folding beams, which are equivalent to springs, and the S-shaped folding beam fixed anchor point area is a bearing block, so that when the movable mass moves upward in the X direction, it can restore to the original state. A plurality of air damping holes are densely and neatly arranged at the left and right ends of the transverse region, so that when the movable mass moves, air resistance interference can be avoided. A left upper Y-axis mass branch, a middle upper Y-axis mass branch and a right upper Y-axis mass branch are arranged in the middle part above the transverse region, a plurality of air damping holes are densely and neatly arranged on the body of the left upper Y-axis mass branch, and a group of densely arranged Y-axis mass combs are connected to the left and right sides of the left upper Y-axis mass branch, which are used to connect the driving Y-axis combs. The length of the middle upper Y-axis mass branch is smaller than that of the left upper Y-axis mass branch, a rectangular window is opened in the body of the middle upper Y-axis mass branch, and the upper and lower inner edges of the window are respectively connected with the same S-shaped folding beam fixed anchor point area through corresponding S-shaped folding beams, which are equivalent to springs, and the S-shaped folding beam fixed anchor point area is a bearing block, so that when the movable mass moves upward in the Y direction, it can restore to the original state. A group of densely arranged Y-axis mass combs are connected to the left and right outer sides of the middle upper Y-axis mass branch; a plurality of air damping holes are densely and neatly arranged on the body of the right upper Y-axis mass branch, and all the air damping holes are used to avoid air resistance interference during measurement. A group of densely arranged Y-axis mass combs are connected to the left and right sides of the right upper Y-axis mass branch; a left lower Y-axis mass branch, a middle lower Y-axis mass branch and a right lower Y-axis mass branch are arranged below the transverse region, the left lower Y-axis mass branch and the right lower Y-axis mass branch are respectively located at the left and right ends of the transverse region, a group of densely arranged Y-axis mass combs are integrally connected to the left side of the left lower Y-axis mass branch and the left side of the cross beam, a group of densely arranged Y-axis mass combs are integrally connected to the right side of the right lower Y-axis mass branch and the right side of the cross beam, and densely arranged Y-axis mass combs are also connected to the inner sides of the left lower Y-axis mass branch and the right lower Y-axis mass branch; a plurality of air damping holes are densely and neatly arranged on the body of the middle lower Y-axis mass branch, two X-axis mass branches are connected to the left and right sides of the middle lower Y-axis mass branch, the two X-axis mass branches on both sides are arranged at intervals, a group of densely arranged X-axis mass combs are connected to the left and right sides of each X-axis mass branch, which are used to connect the driving X-axis combs.The left end top of the transverse area is provided with a first embedded anti-collision platform, and the right end top is provided with a second embedded anti-collision platform, the first embedded anti-collision platform and the second embedded anti-collision platform are both shaped as two identical square movable mass flexible stop blocks, used for connecting the anti-collision platform anchor point area, forming the first and second anti-collision areas, so that the movable mass can reduce the swing amplitude when impacted.

[0007] The first structure unit includes an upper Y-axis driving comb anchor point area, two anti-collision platform anchor point areas, a left X-axis driving comb anchor point area, and a right X-axis driving comb anchor point area. The upper Y-axis driving comb anchor point area is square in shape and surrounds the periphery of the upper structure of the movable mass. The two anti-collision platform anchor point areas are square and located at corresponding positions of the first embedded anti-collision platform and the second embedded anti-collision platform, respectively. The anti-collision platform anchor point areas are provided with a fixed driving flexible stop block. The shape and size of the fixed driving flexible stop block match the spacing between the two movable mass flexible stop blocks. The fixed driving flexible stop block is inserted between the two movable mass flexible stop blocks without contact, so that the two anti-collision platform anchor point areas form anti-collision gaps with the first embedded anti-collision platform and the second embedded anti-collision platform, respectively, forming anti-collision areas. The two anti-collision platform anchor point areas are embedded in the upper Y-axis driving comb anchor point area without contact. The comb gaps formed by each group of mass Y-axis combs are not embedded with corresponding driving Y-axis combs without contact. The comb gaps formed by each group of mass X-axis combs are not embedded with corresponding driving X-axis combs without contact. The driving Y-axis combs located on the periphery are fixed to the Y-axis driving comb anchor point area. The driving X-axis combs located on the left side of the middle and lower Y-axis mass branches and the driving Y-axis combs located on the inner side of the left lower Y-axis mass branch are fixed to the left X-axis driving comb anchor point area. The driving X-axis combs located on the right side of the middle and lower Y-axis mass branches and the driving Y-axis combs located on the inner side of the right lower Y-axis mass branch are fixed to the right X-axis driving comb anchor point area. The mass Y-axis combs and the corresponding matching driving Y-axis combs form variable gap sensitive differential capacitance along the Y-axis direction. The mass X-axis combs and the corresponding matching driving X-axis combs form variable gap sensitive differential capacitance along the X-axis direction. Specifically, a single mass comb and two corresponding driving combs form a variable gap sensitive differential capacitor, so that the overall mass comb and the driving comb form X-direction or Y-direction variable gap sensitive differential capacitor. When the same acceleration is applied in the X-direction and the Y-direction, the displacement of the movable mass is the same.

[0008] The left end bottom of the transverse area of the lower part of the movable mass is provided with a third embedded anti-collision platform, and the right end bottom is provided with a fourth embedded anti-collision platform. The third embedded anti-collision platform and the fourth embedded anti-collision platform are both in the shape of two identical square movable mass flexible stop blocks. The two anti-collision platform anchor point areas below the second structural unit are located at the corresponding positions of the third embedded anti-collision platform and the fourth embedded anti-collision platform. The connection structure of the third embedded anti-collision platform and the fourth embedded anti-collision platform with the corresponding anti-collision platform anchor point area is the same as the connection structure of the first and second embedded anti-collision platforms above and the anti-collision platform anchor point area, forming the third and fourth anti-collision areas.

[0009] The second structural unit includes a lower Y-axis driving comb anchor point area, and the structure after removing the lower Y-axis driving comb anchor point area is the same as the first structural unit. In order to lead out the electrodes of the movable mass, the lower Y-axis driving comb anchor point area is divided into a left Y-axis driving comb anchor point area, a lower left Y-axis driving comb anchor point area, a middle lower Y-axis driving comb anchor point area, a lower right Y-axis driving comb anchor point area, and a right Y-axis driving comb anchor point area, which are used to lead out the electrodes of the mass in different parts. The overall shape of the lower Y-axis driving comb anchor point area is the same as that of the upper Y-axis driving comb anchor point area and surrounds the periphery of the lower structure of the movable mass. The two anti-collision platform anchor point areas below do not contact and are embedded in the left Y-axis driving comb anchor point area and the right Y-axis driving comb anchor point area, respectively.

[0010] Further, the anti-overload fixed anchor point area includes a first anti-overload fixed anchor point area, a second anti-overload fixed anchor point area, a third anti-overload fixed anchor point area, and a fourth anti-overload fixed anchor point area, which are independent of each other and are used to control the displacement of the movable mass when it is impacted. The middle structure of the movable mass includes three groups of mass stop blocks, a left mass stop block I for connecting the corresponding lower left Y-axis mass block branch of the upper and lower parts of the movable mass, a middle mass stop block II for connecting the corresponding middle lower Y-axis mass block branch of the upper and lower parts of the movable mass, and a right mass stop block III for connecting the corresponding right lower Y-axis mass block branch of the upper and lower parts of the movable mass. The mass stop block I, the mass stop block II, and the mass stop block III have the same structure, and the mass stop block I and the mass stop block III have a plurality of air damping holes arranged densely and uniformly on the body. Each mass stop block has two symmetric first flexible stop blocks on the left and right sides, and the first flexible stop block has a stepped boss shape. The first anti-overload fixed anchor point area is located on the left side of the mass stop block I, the second anti-overload fixed anchor point area is located between the mass stop block I and the mass stop block II, the third anti-overload fixed anchor point area is located between the mass stop block II and the mass stop block III, and the fourth anti-overload fixed anchor point area is located on the right side of the mass stop block III. All anti-overload fixed anchor point areas are embedded in the corresponding first flexible stop blocks on the mass stop blocks through the second flexible stop blocks, without contact, and with a stop gap. The part connecting the mass stop block I, the first anti-overload fixed anchor point area, and the second anti-overload fixed anchor point area forms a first anti-biaxial overload embedded fork tooth stop area, the part connecting the mass stop block II, the second anti-overload fixed anchor point area, and the third anti-overload fixed anchor point area forms a second anti-biaxial overload embedded fork tooth stop area, and the part connecting the mass stop block III, the third anti-overload fixed anchor point area, and the fourth anti-overload fixed anchor point area forms a third anti-biaxial overload embedded fork tooth stop area.

[0011] Preferably, the gap between each anti-collision platform anchor point area and the corresponding embedded anti-collision platform is 3 um, i.e., the gap of the first, second, third, and fourth anti-collision areas is 3 um. In each anti-biaxial overload embedded fork tooth stop area, the gap between the corresponding anti-overload fixed anchor point area and the corresponding connected mass stop block is 3 um, i.e., the gap between each anti-overload fixed anchor point area and the corresponding connected mass stop block in the first, second, third, and fourth anti-biaxial overload embedded fork tooth stop area is 3 um.

[0012] Preferably, the short interval between the mass block Y-axis comb teeth and the driving Y-axis comb teeth is 4 um, and the long interval is 12 um; the short interval between the mass block X-axis comb teeth and the driving X-axis comb teeth is 4 um, and the long interval is 12 um, which can meet further range requirements; the capacitive accelerometer sensor, when the same acceleration is applied to the X and Y axes, the displacement of the movable mass block is the same, and the X and Y axes have the same range of ~ g.

[0013] Preferably, when the same impact is applied to the X and Y axes, the first, second and third anti-biaxial overload embedded fork tooth stop regions make the displacement of the movable mass block less than 4 um; the first, second, third and fourth embedded anti-collision platforms can reduce the swing amplitude of the movable mass block when impacted.

[0014] Preferably, the mass block Y-axis comb teeth are in a bottom suspended state, and the driving Y-axis comb teeth are also in a bottom suspended state, i.e. the thickness is less than the thickness of each corresponding anchor point region; the mass block X-axis comb teeth are in a bottom suspended state, and the driving X-axis comb teeth are also in a bottom suspended state, i.e. the thickness is less than the thickness of the left X-axis driving comb teeth anchor point region and the right X-axis driving comb teeth anchor point region; the thickness of the first, second and third anti-biaxial overload embedded fork tooth stop regions is less than the thickness of each corresponding anti-overload fixed anchor point region. Further, the S-shaped folded beam is suspended at the bottom, and the thickness of the S-shaped folded beam fixed anchor point region is greater than the thickness of the S-shaped folded beam. These three features make the movement of the movable mass block, including the mass block Y-axis comb teeth, the mass block X-axis comb teeth and the three mass stop blocks, free, and also make the movable mass block able to restore to its original state after impact.

[0015] Compared with the prior art, the application has the following beneficial effects: the biaxial impact-resistant capacitive accelerometer sensor based on embedded fork tooth stop and anti-collision platform provided by the application has the following advantages: ① the three anti-biaxial overload embedded fork tooth stop regions are designed, when in a high overload environment, the fork tooth stop can deform through the contact between the teeth, reduce the impact strength, play a buffering role for the folded beam structure, reduce the regional stress caused by large deformation of the folded beam, and protect the sensitive structure; ② the four embedded anti-collision platforms are designed, which can reduce the oscillation amplitude of the sensitive structure in a high overload environment; ③ the interval ratio between the mass block comb teeth and the driving comb teeth is 1:3, and the whole structure is symmetrical about the X and Y axes, which forms a differential capacitive unit and effectively reduces cross-coupling. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The figure is a structural schematic diagram of the application.

[0017] Figure 2 For Figure 1 Enlarged view at A in the middle.

[0018] Figure 3 For Figure 1 Enlarged view at B in the middle.

[0019] Figure 4 For Figure 1 Enlarged view at C in the middle.

[0020] Figure 5 For

[0021] Figure 6 For

[0022] Figure 7 For

[0023] Figure 8 For

[0024] The figure is marked as follows: 1-first anti-overload fixed anchor area, 2-second anti-overload fixed anchor area, 3-third anti-overload fixed anchor area, 4-fourth anti-overload fixed anchor area, 41-upper Y-axis driving comb anchor area, 42-anti-collision platform anchor area, 43-left X-axis driving comb anchor area, 44-right X-axis driving comb anchor area, 45-lower Y-axis driving comb anchor area, 451-left Y-axis driving comb anchor area, 452-left lower Y-axis driving comb anchor area, 453-middle lower Y-axis driving comb anchor area, 454-right lower Y-axis driving comb anchor area, 455-right Y-axis driving comb anchor area, 51-first embedded anti-collision platform, 52-second embedded anti-collision platform, 53-third embedded anti-collision platform, 54-fourth embedded anti-collision platform, 61-mass Y-axis comb, 62-driving Y-axis comb, 63-mass X-axis comb, 64-driving X-axis comb, 65-S-shaped folding beam fixed anchor area, 66-S-shaped folding beam, 11-first anti-biaxial overload embedded fork stop area, 12-second anti-biaxial overload embedded fork stop area, 13-third anti-biaxial overload embedded fork stop area, 110-movable mass, 111-air damping hole, 1101-cross beam, 1102-left upper Y-axis mass branch, 1103-middle upper Y-axis mass branch, 1104-right upper Y-axis mass branch, 1105-left lower Y-axis mass branch, 1106-middle lower Y-axis mass branch, 1107-right lower Y-axis mass branch, 31-first flexible stop block, 32-second flexible stop block, 21-movable mass flexible stop block, 22-fixed driving flexible stop block. DETAILED DESCRIPTION

[0025] The application will be further described below in combination with specific embodiments.

[0026] A biaxial impact-resistant capacitive accelerometer sensor based on embedded fork stop and anti-collision platform, as shown in Figures 1 to 5 The figure is marked as follows: 1-first anti-overload fixed anchor area, 2-second anti-overload fixed anchor area, 3-third anti-overload fixed anchor area, 4-fourth anti-overload fixed anchor area, 41-upper Y-axis driving comb anchor area, 42-anti-collision platform anchor area, 43-left X-axis driving comb anchor area, 44-right X-axis driving comb anchor area, 45-lower Y-axis driving comb anchor area, 451-left Y-axis driving comb anchor area, 452-left lower Y-axis driving comb anchor area, 453-middle lower Y-axis driving comb anchor area, 454-right lower Y-axis driving comb anchor area, 455-right Y-axis driving comb anchor area, 51-first embedded anti-collision platform, 52-second embedded anti-collision platform, 53-third embedded anti-collision platform, 54-fourth embedded anti-collision platform, 61-mass Y-axis comb, 62-driving Y-axis comb, 63-mass X-axis comb, 64-driving X-axis comb, 65-S-shaped folding beam fixed anchor area, 66-S-shaped folding beam, 11-first anti-biaxial overload embedded fork stop area, 12-second anti-biaxial overload embedded fork stop area, 13-third anti-biaxial overload embedded fork stop area, 110-movable mass, 111-air damping hole, 1101-cross beam, 1102-left upper Y-axis mass branch, 1103-middle upper Y-axis mass branch, 1104-right upper Y-axis mass branch, 1105-left lower Y-axis mass branch, 1106-middle lower Y-axis mass branch, 1107-right lower Y-axis mass branch, 31-first flexible stop block, 32-second flexible stop block, 21-movable mass flexible stop block, 22-fixed driving flexible stop block.

[0027] In this embodiment, the following preferred solutions are also adopted:

[0028] The structure of the upper part of the movable mass 110 includes a transverse area 1101, the middle part of which is provided with a rectangular window, and the left and right inner edges of the window are connected with the same S-shaped folding beam fixed anchor point area 65 through corresponding S-shaped folding beams 66, and the left and right end parts of the transverse area 1101 are also provided with a plurality of air damping holes 111 arranged densely and neatly; the middle part above the transverse area 1101 is provided with a left upper Y-axis mass branch 1102, a middle upper Y-axis mass branch 1103 and a right upper Y-axis mass branch 1104, the body of the left upper Y-axis mass branch 1102 is provided with a plurality of air damping holes 111 arranged densely and neatly, and each side of the left upper Y-axis mass branch 1102 is connected with a group of mass Y-axis combs 61 arranged densely; the length of the middle upper Y-axis mass branch 1103 is smaller than that of the left upper Y-axis mass branch 1102, the body of the middle upper Y-axis mass branch 1103 is provided with a rectangular window, and the upper and lower inner edges of the window are connected with the same S-shaped folding beam fixed anchor point area 65 through corresponding S-shaped folding beams 66, and each side of the left and right outer sides of the middle upper Y-axis mass branch 1103 is also connected with a group of mass Y-axis combs 61 arranged densely; the body of the right upper Y-axis mass branch 1104 is provided with a plurality of air damping holes 111 arranged densely and neatly, and each side of the right upper Y-axis mass branch 1104 is connected with a group of mass Y-axis combs 61 arranged densely; the lower part of the transverse area 1101 is provided with a left lower Y-axis mass branch 1105, a middle lower Y-axis mass branch 1106 and a right lower Y-axis mass branch 1107, the left lower Y-axis mass branch 1105 and the right lower Y-axis mass branch 1107 are respectively located at the left and right ends of the transverse area 1101, the left side of the left lower Y-axis mass branch 1105 and the left side of the transverse beam 1101 are integrally connected with a group of mass Y-axis combs 61 arranged densely, the right side of the right lower Y-axis mass branch 1107 and the right side of the transverse beam 1101 are integrally connected with a group of mass Y-axis combs 61 arranged densely, and the inner sides of the left lower Y-axis mass branch 1105 and the right lower Y-axis mass branch 1107 are also connected with mass Y-axis combs 61 arranged densely; the body of the middle lower Y-axis mass branch 1106 is provided with a plurality of air damping holes 111 arranged densely and neatly, and each side of the middle lower Y-axis mass branch 1106 is connected with two X-axis mass branches 1107, the two X-axis mass branches 1107 on both sides are arranged evenly, and each X-axis mass branch 1107 is connected with a group of mass X-axis combs 63 arranged densely on both sides; the left end top of the transverse area 1101 is provided with a first embedded anti-collision platform 51, and the right end top is provided with a second embedded anti-collision platform 52, and the shapes of the first embedded anti-collision platform 51 and the second embedded anti-collision platform 52 are both two identical square movable mass flexible stop blocks 21.The first structure unit includes an upper Y-axis driving comb anchor point area 41, two anti-collision platform anchor point areas 42, a left X-axis driving comb anchor point area 43, and a right X-axis driving comb anchor point area 44. The upper Y-axis driving comb anchor point area 41 has a square outer shape and surrounds the periphery of the upper structure of the movable mass 110. The two anti-collision platform anchor point areas 42 are square and are located at corresponding positions of the first embedded anti-collision platform 51 and the second embedded anti-collision platform 52, respectively. The anti-collision platform anchor point area 42 is provided with a fixed driving flexible stop block 22. The shape and size of the fixed driving flexible stop block 22 match the interval between the two movable mass flexible stop blocks 21, and the fixed driving flexible stop block 22 is inserted between the two movable mass flexible stop blocks 21 without contact, so that the two anti-collision platform anchor point areas 42 form anti-collision gaps with the first embedded anti-collision platform 51 and the second embedded anti-collision platform 52, respectively. The two anti-collision platform anchor point areas 42 are embedded in the upper Y-axis driving comb anchor point area 41 without contact. The corresponding driving Y-axis combs 62 are inserted into the comb gaps formed by each group of mass Y-axis combs 61 without contact. The corresponding driving X-axis combs 64 are inserted into the comb gaps formed by each group of mass X-axis combs 63 without contact. The driving Y-axis combs 62 located at the periphery are fixed to the Y-axis driving comb anchor point area 41. The driving X-axis combs 64 located at the left side of the middle and lower Y-axis mass branch 1106 and the driving Y-axis combs 62 located at the inner side of the left lower Y-axis mass branch 1105 are fixed to the left X-axis driving comb anchor point area 43. The driving X-axis combs 64 located at the right side of the middle and lower Y-axis mass branch 1106 and the driving Y-axis combs 62 located at the inner side of the right lower Y-axis mass branch 1107 are fixed to the right X-axis driving comb anchor point area 44. The mass Y-axis combs 61 and the corresponding matching driving Y-axis combs 62 form variable gap sensitive differential capacitors along the Y-axis direction. The mass X-axis combs 63 and the corresponding matching driving X-axis combs 64 form variable gap sensitive differential capacitors along the X-axis direction.

[0029] ②The left end bottom of the transverse area 1101 of the lower part of the movable mass 110 is provided with a third embedded anti-collision platform 53, and the right end bottom is provided with a fourth embedded anti-collision platform 54, the shapes of the third embedded anti-collision platform 53 and the fourth embedded anti-collision platform 54 are both two identical square movable mass flexible stop blocks 21; the second structural unit includes a lower Y-axis driving comb tooth anchor point area 45, and the structure after removing the lower Y-axis driving comb tooth anchor point area 45 is the same as that of the first structural unit; the lower Y-axis driving comb tooth anchor point area 45 is divided into a left Y-axis driving comb tooth anchor point area 451, a lower left Y-axis driving comb tooth anchor point area 452, a middle lower Y-axis driving comb tooth anchor point area 453, a lower right Y-axis driving comb tooth anchor point area 454, and a right Y-axis driving comb tooth anchor point area 455 for leading out mass block electrodes in different parts; the two lower anti-collision platform anchor point areas 42 are located at the corresponding positions of the third embedded anti-collision platform 53 and the fourth embedded anti-collision platform 54, and the connection structures of the third embedded anti-collision platform 53 and the fourth embedded anti-collision platform 54 and the corresponding anti-collision platform anchor point area 42 are the same as those of the upper first and second embedded anti-collision platforms and the anti-collision platform anchor point area 42; the overall shape of the lower Y-axis driving comb tooth anchor point area 45 is the same as that of the upper Y-axis driving comb tooth anchor point area 41 and surrounds the periphery of the lower structure of the movable mass 110; the two lower anti-collision platform anchor point areas 42 that do not contact are respectively embedded in the left Y-axis driving comb tooth anchor point area 451 and the right Y-axis driving comb tooth anchor point area 455.

[0030] ③The anti-overload fixed anchor point area includes first, second, third and fourth anti-overload fixed anchor point areas 1, 2, 3 and 4, respectively. The middle structure of the movable mass 110 includes three groups of mass stop blocks. The left mass stop block I is used to connect the corresponding lower left Y-axis mass block branch 1105 of the upper and lower parts of the movable mass 110. The middle mass stop block II is used to connect the corresponding middle lower Y-axis mass block branch 1106 of the upper and lower parts of the movable mass 110. The right mass stop block III is used to connect the corresponding right lower Y-axis mass block branch 1107 of the upper and lower parts of the movable mass 110. The mass stop block I, the mass stop block II and the mass stop block III have the same structure. The mass stop block I and the mass stop block III have a plurality of air damping holes 111 arranged densely and uniformly on the body. Each mass stop block has two symmetrical first flexible stop blocks 31 on the left and right sides. The first flexible stop block 31 is in the shape of a stepped boss. The first anti-overload fixed anchor point area 1 is located on the left side of the mass stop block I. The second anti-overload fixed anchor point area 2 is located between the mass stop block I and the mass stop block II. The third anti-overload fixed anchor point area 3 is located between the mass stop block II and the mass stop block III. The fourth anti-overload fixed anchor point area 4 is located on the right side of the mass stop block III. All anti-overload fixed anchor point areas are embedded in the first flexible stop block 31 on the corresponding mass stop block through the second flexible stop block 32 of the anti-overload fixed anchor point area itself, without contact connection, and with a stop gap. The part connecting the mass stop block I, the first anti-overload fixed anchor point area 1 and the second anti-overload fixed anchor point area 2 forms a first anti-biaxial overload embedded fork tooth stop area 11. The part connecting the mass stop block II, the second anti-overload fixed anchor point area 2 and the third anti-overload fixed anchor point area 3 forms a second anti-biaxial overload embedded fork tooth stop area 12. The part connecting the mass stop block III, the third anti-overload fixed anchor point area 3 and the fourth anti-overload fixed anchor point area 4 forms a third anti-biaxial overload embedded fork tooth stop area 13.

[0031] ④The gap between each anti-collision platform anchor point area 42 and the corresponding embedded anti-collision platform is 3 um. In each anti-biaxial overload embedded fork tooth stop area, the gap between the corresponding anti-overload fixed anchor point area and the corresponding connected mass stop block is 3 um. The short interval between the mass block Y-axis comb teeth 61 and the driving Y-axis comb teeth 62 is 4 um, and the long interval is 12 um. The short interval between the mass block X-axis comb teeth 63 and the driving X-axis comb teeth 64 is 4 um, and the long interval is 12 um.

[0032] ⑤The capacitive accelerometer sensor has the same acceleration on the X and Y axes, the displacement of the movable mass (110) as a whole is the same, and the X and Y axes have the same range of 0~50g.

[0033] (6) The same impact is applied on the X and Y axes respectively, the first anti-biaxial overload embedded fork tooth stop zone 11, the second anti-biaxial overload embedded fork tooth stop zone 12, and the third anti-biaxial overload embedded fork tooth stop zone 13 make the displacement of the movable mass 110 as a whole less than 4um; the first embedded anti-collision platform 51, the second embedded anti-collision platform 52, the third embedded anti-collision platform 53, and the fourth embedded anti-collision platform 54 can reduce the swing amplitude of the movable mass 110 when impacted.

[0034] (7) The mass Y-axis comb teeth 61 are in a bottom suspended state, and the driving Y-axis comb teeth 62 are also in a bottom suspended state, i.e., the thickness is less than the thickness of each anchor point area connected; the mass X-axis comb teeth 63 are in a bottom suspended state, and the driving X-axis comb teeth 64 are also in a bottom suspended state, i.e., the thickness is less than the thickness of the left X-axis driving comb teeth anchor point area 43 and the right X-axis driving comb teeth anchor point area 44. The thickness of the first anti-biaxial overload embedded fork tooth stop zone 11, the second anti-biaxial overload embedded fork tooth stop zone 12, and the third anti-biaxial overload embedded fork tooth stop zone 13 is less than the thickness of each corresponding anti-overload fixed anchor point area. The S-shaped folded beam 66 is suspended at the bottom, and the thickness of the S-shaped folded beam fixed anchor point area 65 is greater than the thickness of the S-shaped folded beam 66.

[0035] The specific operation of the embodiment is: when the movable mass 110 is subjected to Y-axis acceleration, the movable mass 110 moves in the Y-axis direction through the bending and compression of the Y-direction S-shaped folded beam 66. When the movable mass 110 moves downward, the capacitance of the upper half of the Y-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the upper Y-axis driving comb teeth anchor point area 41 decreases, and the capacitance of the lower half of the Y-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the lower Y-axis driving comb teeth anchor point area 45 increases. When the movable mass 110 moves upward, the capacitance of the upper half of the Y-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the upper Y-axis driving comb teeth anchor point area 41 increases, and the capacitance of the lower half of the Y-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the lower Y-axis driving comb teeth anchor point area 45 decreases, forming a Y-direction differential structure.

[0036] When the movable mass 110 is subjected to an X-axis acceleration, the movable mass 110 moves in the X-axis direction through the bending and compression of the S-shaped folding beam 66 in the X direction. When the movable mass 110 moves to the right, the capacitance of the left half of the X-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the left X-axis drive comb anchor point area 43 decreases, and the capacitance of the right half of the X-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the right X-axis drive comb anchor point area 44 increases. When the movable mass 110 moves to the right, the capacitance of the left half of the X-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the left X-axis drive comb anchor point area 43 increases, and the capacitance of the right half of the X-direction variable gap sensitive differential capacitor formed by the movable mass 110 and the right X-axis drive comb anchor point area 44 decreases, forming a differential structure in the X direction.

[0037] As shown in Figure 6 , the first structure unit and the second structure unit contain the S-shaped folding beam fixed anchor area 65 and the S-shaped folding beam 66. The S-shaped folding beam 66 can realize the horizontal movement of the movable mass through compression and stretching, and can also realize the vertical movement of the movable mass through bending.

[0038] As shown in Figure 3 and Figure 8 , each anti-biaxial overload embedded fork stop area also contains a first flexible stop block 31 and a second flexible stop block 32. In a high overload environment, the flexible stop block can deform through the contact between the teeth and the teeth, reduce the deformation of the movable mass, reduce the impact strength, buffer the folding beam structure, and reduce the regional stress caused by large deformation of the folding beam.

[0039] As shown in Figure 7 , each anti-collision platform anchor point area 42 and the corresponding embedded anti-collision platform form an anti-collision area, which also contains a movable mass flexible stop block 21 and a fixed drive flexible stop block 22. When the movable mass 110 is subjected to an impact, the movable mass flexible stop block 21 and the fixed drive flexible stop block 22 can effectively reduce the swing amplitude of the movable mass.

[0040] As shown in Figure 1 , when a certain acceleration is applied to the movable mass 110, high-voltage direct current and low-voltage alternating current signals with the same frequency but a phase difference of 180° are applied to the upper Y-axis drive comb anchor point area 41 and the lower Y-axis comb anchor point area 45 for n periods and then stopped, and high-voltage direct current and low-voltage alternating current signals with the same frequency but a phase difference of 180° are applied to the left X-axis drive comb anchor point area 43 and the right X-axis comb anchor point area 44 for n periods and then stopped. The first n periods can obtain the capacitance change under the influence of the Y-axis acceleration, and the last n periods can obtain the capacitance change under the influence of the X-axis acceleration. The modulus of the two can obtain the total capacitance change.

[0041] The scope of the application is not limited to the above specific embodiments, and the application can have various modifications and alterations, and any modifications, improvements and equivalent replacements made within the concept and principle of the application should be included in the protection scope of the application.

Claims

1. A dual-axis shock-resistant capacitive accelerometer sensor based on embedded tine stops and bump stops, characterized by: The movable mass (110) is a whole structure, and the anti-overload fixed anchor area is located between the first structure unit and the second structure unit; the movable mass (110) is divided into upper, middle and lower parts according to the positions of the first structure unit, the anti-overload fixed anchor area and the second structure unit, and the upper and lower parts of the movable mass (110) are the same and symmetrical; the first structure unit and the second structure unit each include a plurality of driving comb anchor areas, each driving comb anchor area is provided with an anti-collision area and a comb connecting area at the position connected with the movable mass (110), the comb connecting area forms a corresponding variable gap sensitive differential capacitor; the position connected with the movable mass (110) of the anti-overload fixed anchor area forms a plurality of anti-biaxial overload embedded fork stop areas; The structure of the upper part of the movable mass (110) includes a transverse area (1101), the left end top of the transverse area (1101) is provided with a first embedded anti-collision platform (51), and the right end top is provided with a second embedded anti-collision platform (52), the shapes of the first embedded anti-collision platform (51) and the second embedded anti-collision platform (52) are both two same square movable mass flexible stop blocks (21); The first structure unit includes an upper Y-axis driving comb anchor area (41), two anti-collision platform anchor areas (42), a left X-axis driving comb anchor area (43) and a right X-axis driving comb anchor area (44), the outer shape of the upper Y-axis driving comb anchor area (41) is square, and surrounds the periphery of the upper structure of the movable mass (110); the two anti-collision platform anchor areas (42) are square, and are respectively located at the corresponding positions of the first embedded anti-collision platform (51) and the second embedded anti-collision platform (52), and the anti-collision platform anchor area (42) is provided with a fixed driving flexible stop block (22), the shape and size of the fixed driving flexible stop block (22) match the interval between the two movable mass flexible stop blocks (21), and the fixed driving flexible stop block (22) is inserted between the two movable mass flexible stop blocks (21) without contact, so that the two anti-collision platform anchor areas (42) form anti-collision gaps with the first embedded anti-collision platform (51) and the second embedded anti-collision platform (52) respectively; The left end bottom of the transverse area (1101) of the lower part of the movable mass (110) is provided with a third embedded anti-collision platform (53), and the right end bottom is provided with a fourth embedded anti-collision platform (54), the shapes of the third embedded anti-collision platform (53) and the fourth embedded anti-collision platform (54) are both two same square movable mass flexible stop blocks (21); ​ The second structural unit comprises a lower Y-axis driving comb anchor point area (45), and the structure after removing the lower Y-axis driving comb anchor point area (45) is the same as the first structural unit; the lower Y-axis driving comb anchor point area (45) is divided into a left Y-axis driving comb anchor point area (451), a left lower Y-axis driving comb anchor point area (452), a middle lower Y-axis driving comb anchor point area (453), a right lower Y-axis driving comb anchor point area (454) and a right Y-axis driving comb anchor point area (455) for leading out mass block electrodes in different positions; two lower anti-collision platform anchor point areas (42) are located at positions corresponding to a third embedded anti-collision platform (53) and a fourth embedded anti-collision platform (54), and the connection structures of the third embedded anti-collision platform (53) and the fourth embedded anti-collision platform (54) with the corresponding anti-collision platform anchor point areas (42) are the same as the connection structures of the upper first and second embedded anti-collision platforms with the anti-collision platform anchor point areas (42).

2. A dual axis impact resistant capacitive accelerometer sensor based on embedded tine stops and bump stops as claimed in claim 1, wherein: The middle part of the transverse area (1101) is provided with a rectangular window, and the left and right inner edges of the window are connected with the same S-shaped folding beam fixed anchor point area (65) in the middle through corresponding S-shaped folding beams (66); the left and right end parts of the transverse area (1101) are also provided with a plurality of air damping holes (111) arranged densely and neatly; the upper middle part of the transverse area (1101) is provided with a left upper Y-axis mass block branch (1102), a middle upper Y-axis mass block branch (1103) and a right upper Y-axis mass block branch (1104); the left upper Y-axis mass block branch (1102) is provided with a plurality of air damping holes (111) arranged densely and neatly on the body; the left and right sides of the left upper Y-axis mass block branch (1102) are respectively connected with a group of mass block Y-axis combs (61) arranged densely; the middle upper Y-axis mass block branch (1103) is shorter than the left upper Y-axis mass block branch (1102); the middle upper Y-axis mass block branch (1103) is provided with a rectangular window in the body, and the upper and lower inner edges of the window are connected with the same S-shaped folding beam fixed anchor point area (65) in the middle through corresponding S-shaped folding beams (66); the left and right outer sides of the middle upper Y-axis mass block branch (1103) are respectively connected with a group of mass block Y-axis combs (61) arranged densely; the right upper Y-axis mass block branch (1104) is provided with a plurality of air damping holes (111) arranged densely and neatly on the body; the left and right sides of the right upper Y-axis mass block branch (1104) are respectively connected with a group of mass block Y-axis combs (61) arranged densely; the lower part of the transverse area (1101) is provided with a left lower Y-axis mass block branch (1105), a middle lower Y-axis mass block branch (1106) and a right lower Y-axis mass block branch (1107); the left lower Y-axis mass block branch (1105) and the right lower Y-axis mass block branch (1107) are respectively located at the left and right ends of the transverse area (1101); the left lower Y-axis mass block branch (1105) is integrally connected with a group of mass block Y-axis combs (61) arranged densely on the left side of the transverse beam (1101); the right lower Y-axis mass block branch (1107) is integrally connected with a group of mass block Y-axis combs (61) arranged densely on the right side of the transverse beam (1101); the inner sides of the left lower Y-axis mass block branch (1105) and the right lower Y-axis mass block branch (1107) are also connected with mass block Y-axis combs (61) arranged densely; the middle lower Y-axis mass block branch (1106) is provided with a plurality of air damping holes (111) arranged densely and neatly on the body; the left and right sides of the middle lower Y-axis mass block branch (1106) are respectively connected with two X-axis mass block branches (1107); the two X-axis mass block branches (1107) on the two sides are arranged evenly; the two sides of each X-axis mass block branch (1107) are respectively connected with a group of mass block X-axis combs (63) arranged densely. Two anti-collision platform anchor points (42) are embedded in the upper Y-axis driving comb anchor point area (41) without contact; the comb gaps formed by each group of mass Y-axis combs (61) are embedded without contact and correspondingly inserted with driving Y-axis combs (62); the comb gaps formed by each group of mass X-axis combs (63) are embedded without contact and correspondingly inserted with driving X-axis combs (64); the driving Y-axis combs (62) located at the periphery are fixed to the Y-axis driving comb anchor point area (41); the driving X-axis combs (64) located at the left side of the middle and lower Y-axis mass branch (1106) and the driving Y-axis combs (62) located at the inner side of the left lower Y-axis mass branch (1105) are fixed to the left X-axis driving comb anchor point area (43); the driving X-axis combs (64) located at the right side of the middle and lower Y-axis mass branch (1106) and the driving Y-axis combs (62) located at the inner side of the right lower Y-axis mass branch (1107) are fixed to the right X-axis driving comb anchor point area (44); the mass Y-axis combs (61) and the correspondingly matched and inserted driving Y-axis combs (62) form a variable gap sensitive differential capacitor along the Y-axis direction; the mass X-axis combs (63) and the correspondingly matched and inserted driving X-axis combs (64) form a variable gap sensitive differential capacitor along the X-axis direction; The overall shape of the lower Y-axis driving comb anchor point area (45) is the same as that of the upper Y-axis driving comb anchor point area (41) and surrounds the periphery of the lower structure of the movable mass (110); the two anti-collision platform anchor points (42) located at the lower part are respectively embedded in the left Y-axis driving comb anchor point area (451) and the right Y-axis driving comb anchor point area (455) without contact.

3. A dual axis impact resistant capacitive accelerometer sensor based on embedded tine stops and bump stops according to claim 1 or 2, characterized in that: The anti-overload fixed anchor point area includes first, second, third and fourth anti-overload fixed anchor point areas (1, 2, 3, 4) respectively; the middle structure of the movable mass (110) includes three groups of mass stop blocks, the left mass stop block I is used for connecting the corresponding left lower Y-axis mass branch (1105) of the upper and lower parts of the movable mass (110), the middle mass stop block II is used for connecting the corresponding middle and lower Y-axis mass branch (1106) of the upper and lower parts of the movable mass (110), and the right mass stop block III is used for connecting the corresponding right lower Y-axis mass branch (1107) of the upper and lower parts of the movable mass (110); The mass stop block I, the mass stop block II and the mass stop block III have the same structure, the mass stop block I and the mass stop block III are provided with air damping holes (111) arranged densely and uniformly on the bodies; each of the mass stop blocks is provided with two symmetrical first flexible stop blocks (31) on the left and right sides, the first flexible stop blocks (31) are in the shape of stepped bosses, the first anti-overload fixed anchor point area (1) is located on the left side of the mass stop block I, the second anti-overload fixed anchor point area (2) is located between the mass stop block I and the mass stop block II, the third anti-overload fixed anchor point area (3) is located between the mass stop block II and the mass stop block III, and the fourth anti-overload fixed anchor point area (4) is located on the right side of the mass stop block III; all the anti-overload fixed anchor point areas are fitted into and not in contact with the first flexible stop blocks (31) on the corresponding mass stop blocks through the second flexible stop blocks (32) of the anti-overload fixed anchor point areas, and a stop gap is left; the part, where the mass stop block I is connected with the first anti-overload fixed anchor point area (1) and the second anti-overload fixed anchor point area (2), forms a first anti-biaxial overload embedded fork tooth stop area (11), the part, where the mass stop block II is connected with the second anti-overload fixed anchor point area (2) and the third anti-overload fixed anchor point area (3), forms a second anti-biaxial overload embedded fork tooth stop area (12), and the part, where the mass stop block III is connected with the third anti-overload fixed anchor point area (3) and the fourth anti-overload fixed anchor point area (4), forms a third anti-biaxial overload embedded fork tooth stop area (13).

4. A dual axis shock resistant capacitive accelerometer sensor based on embedded prong stop and crash pad according to claim 3, characterized in that: The gap between each anti-collision platform anchor point area (42) and the corresponding embedded anti-collision platform is 3 um; in each anti-biaxial overload embedded fork tooth stop area, the gap between the corresponding anti-overload fixed anchor point area and the corresponding connected mass stop block is 3 um.

5. A dual axis impact resistant capacitive accelerometer sensor based on embedded prong stop and crash pad according to claim 3, characterized in that: The short interval between the mass block Y-axis comb teeth (61) and the driving Y-axis comb teeth (62) is 4 um, and the long interval is 12 um; the short interval between the mass block X-axis comb teeth (63) and the driving X-axis comb teeth (64) is 4 um, and the long interval is 12 um.

6. A dual axis impact resistant capacitive accelerometer sensor based on embedded tine stops and bump stops as claimed in claim 3, wherein: The capacitive accelerometer sensor has the same acceleration applied on the X and Y axes, the displacement of the movable mass block (110) as a whole is the same, and the X and Y axes have the same range of 0-50g.

7. A dual axis shock resistant capacitive accelerometer sensor based on embedded tine stops and bump stops as claimed in claim 5, wherein: When the same impact is applied on the X and Y axes, the first anti-biaxial overload embedded fork tooth stop area (11), the second anti-biaxial overload embedded fork tooth stop area (12) and the third anti-biaxial overload embedded fork tooth stop area (13) make the displacement of the movable mass block (110) as a whole less than 4 um; the first embedded anti-collision platform (51), the second embedded anti-collision platform (52), the third embedded anti-collision platform (53) and the fourth embedded anti-collision platform (54) can reduce the swing amplitude of the movable mass block (110) when impacted.

8. A dual axis impact resistant capacitive accelerometer sensor based on embedded tine stops and bump stops as claimed in claim 3, wherein: The mass Y-axis comb teeth (61) are in a bottom suspended state, the driving Y-axis comb teeth (62) are also in a bottom suspended state, i.e. the thickness is less than the thickness of the corresponding connected anchor point area; the mass X-axis comb teeth (63) are in a bottom suspended state, the driving X-axis comb teeth (64) are also in a bottom suspended state, i.e. the thickness is less than the thickness of the left X-axis driving comb teeth anchor point area (43) and the right X-axis driving comb teeth anchor point area (44).

9. A dual axis impact resistant capacitive accelerometer sensor based on embedded tine stops and bump stops as claimed in claim 3, wherein: The thickness of the first anti-biaxial overload embedded fork tooth stop area (11), the second anti-biaxial overload embedded fork tooth stop area (12) and the third anti-biaxial overload embedded fork tooth stop area (13) is less than the thickness of the corresponding anti-overload fixed anchor point area.

10. A dual axis impact resistant capacitive accelerometer sensor based on embedded tine stops and bump stops as claimed in claim 2, wherein: The S-shaped folded beam (66) is in a bottom suspended state, and the thickness of the S-shaped folded beam fixed anchor point area (65) is greater than the thickness of the S-shaped folded beam (66).

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