Single-island multi-electrode quartz accelerometer

Abstract

The invention belongs to the technical field of accelerometers, and particularly relates to a single-island multi-electrode quartz accelerometer, which comprises an outer shell, a single-conduction multi-electrode acceleration sensing mechanism, a signal conversion and temperature compensation mechanism, an acoustic resonant frequency modulator and an acceleration measuring and calculating mechanism, and is characterized in that the outer shell is of an integrally formed structure; when the single-conductor multi-electrode acceleration sensing mechanism works, acceleration signals are generated, and displacement signals are sensed. When the single-conductor multi-electrode acceleration sensing mechanism senses an acceleration signal, the signal conversion and temperature compensation mechanism automatically converts a displacement signal into a rotation signal and performs temperature compensation; the acoustic resonant frequency modulator and the acceleration measuring and calculating mechanism are used for converting a rotation signal into a displacement signal, amplifying the displacement signal, exciting resonance by using the amplified displacement signal, picking up a resonant frequency signal, and calculating the acceleration according to the variation of the resonant frequency; the problems that in the measurement process, the measurement precision is not stable enough, and the uncertainty of the measurement result is high are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of accelerometer, in particular to a single-island multi-electrode quartz accelerometer. BACKGROUND

[0002] The accelerometer is a measuring instrument for measuring acceleration. Acceleration measurement is an important issue raised by engineering technology. When an object has a large acceleration, the object and the instruments and other objects without relative acceleration carried by the object will be subjected to a force that can produce the same large acceleration, i.e. a dynamic load. To know the dynamic load, the acceleration needs to be measured. The components of a common accelerometer include a shell (fixed to the measured object), a reference mass, a sensitive element, a signal output device, etc. The accelerometer requires a certain range, accuracy, sensitivity, etc.

[0003] Currently, the mainstream quartz accelerometer mainly uses piezoelectric effect or capacitance detection principle for measurement. The piezoelectric type relies on a charge amplifier, which has large low-frequency noise and significant temperature drift. The capacitance type requires high-frequency excitation, is easily affected by electromagnetic interference, and has extremely high difficulty in micro-gap processing. At the same time, both types rely on an external temperature sensor + digital compensation algorithm (such as ADI ADXL1005), which has a corresponding delay and fails in dynamic temperature change scenarios, resulting in unstable measurement accuracy and high uncertainty of the measured data in the measurement process of the current quartz accelerometer. SUMMARY

[0004] This section is intended to summarize some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification to avoid obscuring the purpose of this section, the abstract and the title. Such simplifications or omissions cannot be used to limit the scope of the present application.

[0005] Therefore, the purpose of the present application is to provide a single-island multi-electrode quartz accelerometer to replace the measurement method of the traditional quartz accelerometer, thereby avoiding the problems of unstable measurement accuracy and high uncertainty of the measurement results in the measurement process.

[0006] To solve the above technical problems, according to one aspect of the present application, the present application provides the following technical scheme: A single-island multi-electrode quartz accelerometer, comprising: a shell body which is a one-piece structure; a single-guide multi-electrode acceleration sensing mechanism installed at the inner bottom end of the shell body, wherein the single-guide multi-electrode acceleration sensing mechanism generates an acceleration signal and senses a displacement signal when working; A signal conversion and temperature compensation mechanism is installed in the outer housing and above the single-guide multi-electrode acceleration sensing mechanism, which automatically converts displacement signals into rotation signals and performs temperature compensation when the single-guide multi-electrode acceleration sensing mechanism senses acceleration signals. An acoustic resonance frequency modulator and acceleration measuring mechanism is installed in the outer housing and above the signal conversion and temperature compensation mechanism, which automatically drives the acoustic resonance frequency modulator and acceleration measuring mechanism to work when the signal conversion and temperature compensation mechanism converts acceleration signals into rotation signals, converts the rotation signals into displacement signals, amplifies the displacement signals, excites resonance with the amplified displacement signals, picks up the resonance frequency signals, and calculates the acceleration through the change in the resonance frequency.

[0007] In a preferred embodiment of the single-island multi-electrode quartz accelerometer, the single-guide multi-electrode and velocity sensing mechanism includes a first housing at the bottom of the inner wall of the outer housing, a single-guide quartz beam with multiple sets of electrodes installed on both sides of the inner wall of the first housing, and an acceleration trigger assembly movably connected to the single-guide quartz beam.

[0008] In a preferred embodiment of the single-island multi-electrode quartz accelerometer, the acceleration trigger assembly includes a moving mass block inside the first housing below the single-guide quartz beam, and a flexible hinge chain hinged at one end to the bottom of the single-guide quartz beam and at the other end to the top of the moving mass block.

[0009] In a preferred embodiment of the single-island multi-electrode quartz accelerometer, the signal conversion and temperature compensation mechanism includes a second housing on top of the first housing and sealed from the first housing, a balance wheel movably installed in the second housing, a temperature compensation bimetallic strip coaxially arranged with the balance wheel, a signal conversion assembly for converting the deflection signal of the balance wheel into an electrical signal, and a first transmission assembly having one end transmissionally connected to the balance wheel and the other end transmissionally connected to the moving mass block.

[0010] In a preferred embodiment of the single-island multi-electrode quartz accelerometer, the signal conversion assembly includes a linear variable differential transformer (LVDT) core at one side edge of the balance wheel, and an LVDT coil group installed at the bottom of the inner wall of the second housing and surrounding the motion trajectory of the LVDT core.

[0011] In a preferred embodiment of the single-island multi-electrode quartz accelerometer, the top of the moving mass block is provided with a connecting rod that penetrates through the first housing and the bottom of the second housing. The first transmission assembly comprises a plurality of sawtooth blocks evenly distributed on the circumferential side wall of the balance wheel and a sawtooth plate located at the top of the connecting rod and engaged with the plurality of sawtooth blocks.

[0012] As a preferred scheme of the single-island multi-electrode quartz accelerometer, the acoustic resonant frequency modulator and acceleration measurement mechanism comprises a third shell located at the top of the second shell and having a connecting port at the top, a resonant frequency generating assembly installed on the top inner wall of the third shell, a driving assembly installed in the third shell and in driving connection with the resonant frequency generating assembly, and a second transmission assembly in driving connection with the balance wheel at one end and in driving connection with the driving assembly at the other end.

[0013] As a preferred scheme of the single-island multi-electrode quartz accelerometer, the resonant frequency generating assembly comprises tuning forks symmetrically distributed on the top inner wall of the third shell and V-shaped flexible bridges respectively connected with the arm ends of the two tuning forks, the top of the tuning fork has a thickened area and the terminal surface of the fork arm is polished, and the inner wall of the third shell has receivers on both sides for picking up the resonant frequency.

[0014] As a preferred scheme of the single-island multi-electrode quartz accelerometer, the driving assembly comprises a driving block extending into the limiting sliding slot on both sides of the inner wall of the third shell and a conical top block located at the top of the driving block and corresponding to the V-shaped area of the V-shaped flexible bridge.

[0015] As a preferred scheme of the single-island multi-electrode quartz accelerometer, the side wall of the balance wheel is connected with a first pulley through a rotating shaft. The second transmission assembly comprises a cam rotatingly installed in the shell and corresponding to the bottom of the driving block and a second pulley located on the side wall of the cam and connected with the first pulley through a belt. The outer side wall of the third shell is provided with a micro motor having an output end connected with the side wall of the cam through a rotating shaft.

[0016] Compared with the prior art, the single-island multi-electrode quartz accelerometer has the beneficial effects that the single-guide multi-electrode acceleration sensing mechanism generates and senses the acceleration signal, then the signal conversion and temperature compensation mechanism automatically converts the displacement signal into a rotation signal and performs temperature compensation, at the same time, the acoustic resonance frequency modulator and the acceleration measurement mechanism work, the rotation signal is converted into a displacement signal, then the displacement signal is amplified, the resonance is excited by using the amplified displacement signal, and the resonance frequency signal is picked up, the acceleration is calculated according to the change of the resonance frequency, so that the frequency is used as the output signal, and the single-island multi-electrode quartz accelerometer has the advantages of super-high resolution, strong anti-interference and easy digitization, and the measurement mode of the traditional quartz accelerometer is replaced, and the problems of unstable measurement accuracy and high uncertainty of measurement results in the measurement process are avoided. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the present application will be described in detail below in combination with the drawings and detailed embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them: Figure 1 It is an appearance view of the single-island multi-electrode quartz accelerometer of the present application. Figure 2 It is a schematic view of the internal structure of the single-island multi-electrode quartz accelerometer of the present application. Figure 3 It is a split view of the internal structure of the single-island multi-electrode quartz accelerometer of the present application. Figure 4 It is a sectional view of the internal structure of the single-island multi-electrode quartz accelerometer of the present application. Figure 5 It is a schematic view of the single-guide multi-electrode acceleration sensing mechanism of the single-island multi-electrode quartz accelerometer of the present application. Figure 6 It is a schematic view of the signal conversion and temperature compensation mechanism of the single-island multi-electrode quartz accelerometer of the present application. Figure 7 It is a split view of the acoustic resonance frequency modulator and the acceleration measurement mechanism of the single-island multi-electrode quartz accelerometer of the present application. Figure 8 It is a schematic view of the acoustic resonance frequency modulator and the acceleration measurement mechanism of the single-island multi-electrode quartz accelerometer of the present application.

[0018] In the figure: 100, the outer shell; 200, single guide multi-electrode acceleration sensing mechanism; 210, the first shell; 220, single guide quartz beam; 220a, multiple sets of electrodes; 230, acceleration trigger assembly; 230a, moving mass; 230a-1, connecting rod; 230b, flexible articulated chain; 300, signal conversion and temperature compensation mechanism; 310, the second shell; 320, balance wheel; 320a, the first pulley; 330, temperature compensation bimetallic strip; 340, signal conversion assembly; 340a, LVDT core; 340b, LVDT coil group; 350, the first transmission assembly; 350a, sawtooth block; 350b, sawtooth plate; 400, acoustic resonance frequency modulator and acceleration measurement mechanism; 410, the third shell; 410a, receiver; 410b, connecting port; 410c, micro motor; 420, resonance frequency generating assembly; 420a, tuning fork; 420b, V-shaped flexible bridge; 430, drive assembly; 430a, drive block; 430b, conical top block; 440, the second transmission assembly; 440a, cam; 440b, the second pulley. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0020] Secondly, the present application is described in detail in conjunction with the schematic diagram, in the detailed description of the embodiments of the present application, for the convenience of description, the cross-sectional view of the device structure will be partially enlarged without general proportion, and the schematic diagram is only an example, which should not limit the scope of protection of the present application here. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual production.

[0021] In order to make the objects, technical solutions and advantages of the present application more clear, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0022] The present application provides a single island multi-electrode quartz accelerometer, which replaces the measurement mode of traditional quartz accelerometer, avoids the problems of unstable measurement accuracy and high uncertainty of measurement results in the measurement process.

[0023] Figures 1-8 The structure of the single island multi-electrode quartz accelerometer of the present application is shown, please refer to Figures 1-8 The single island multi-electrode quartz accelerometer is described in detail.

[0024] Example 1 Reference Figures 1-8The application discloses a single-island multi-electrode quartz accelerometer, which comprises a shell 100, a single-guide multi-electrode acceleration sensing mechanism 200, a signal conversion and temperature compensation mechanism 300, and an acoustic resonance frequency modulator and acceleration measurement mechanism 400.

[0025] Reference Figure 1 The shell 100 is used for protecting the whole and the internal components, and is an integrated structure, so that the whole structure is stronger, and the internal components are more stable during measurement. Reference Figures 2-5 The single-guide multi-electrode acceleration sensing mechanism 200 is installed at the inner bottom end of the shell 100, and generates an acceleration signal and senses a displacement signal during work, so that the single-guide multi-electrode acceleration sensing mechanism 200 generates an acceleration signal and senses an acceleration displacement signal, and utilizes the single-guide performance of multiple electrodes acting on the same quartz beam to obtain multiple groups of voltage changes generated due to different stresses at different positions during acceleration. Reference Figures 2-6 The signal conversion and temperature compensation mechanism 300 is used for converting the displacement signal sensed by the single-guide multi-electrode acceleration sensing mechanism 200 during work into a rotary signal and automatically compensating temperature according to the ambient temperature, and is installed in the shell 100 and located above the single-guide multi-electrode acceleration sensing mechanism 200, wherein when the single-guide multi-electrode acceleration sensing mechanism 200 senses an acceleration signal, the signal conversion and temperature compensation mechanism 300 automatically converts the displacement signal into a rotary signal and compensates temperature, so that when the single-guide multi-electrode acceleration sensing mechanism 200 works and transmits the sensed displacement signal to the signal conversion and temperature compensation mechanism 300, the displacement signal is automatically converted into a rotary signal, and the signal conversion and temperature compensation mechanism 300 compensates temperature according to the ambient temperature, so that the response ability of temperature compensation is improved, and the stability of signal response is further improved. Reference Figures 2-7The acoustic resonant frequency modulator and acceleration calculating mechanism 400 is used to calculate the acceleration value by using the change of the resonant frequency after amplifying the acceleration signal. The acoustic resonant frequency modulator and acceleration calculating mechanism 400 is installed in the outer shell 100 and above the signal converting and temperature compensating mechanism 300. When the signal converting and temperature compensating mechanism 300 converts the acceleration signal into the rotation signal, the acoustic resonant frequency modulator and acceleration calculating mechanism 400 is automatically driven to work. The rotation signal is converted into the displacement signal, amplified, and used to stimulate the resonance and pick up the resonant frequency signal. The acceleration is calculated by the change of the resonant frequency. Therefore, when the signal converting and temperature compensating mechanism 300 works, the acoustic resonant frequency modulator and acceleration calculating mechanism 400 automatically converts the rotation signal into the displacement signal, amplifies the displacement signal, picks up the resonant frequency signal by stimulating the resonance with the amplified signal, and calculates the acceleration by the change of the resonant frequency. Therefore, the frequency is used as the output signal, so that the measurement has the advantages of super-high resolution, strong anti-interference, and easy digitalization, and the acceleration measurement is more stable and reliable.

[0026] In the embodiment, the following process is used. The single-guide multi-electrode acceleration sensing mechanism 200 produces the acceleration signal and simultaneously senses the displacement signal generated when the acceleration occurs. When the displacement signal of the acceleration is sensed, the signal converting and temperature compensating mechanism 300 automatically starts to work, converts the displacement signal into the rotation signal, and simultaneously performs the automatic temperature compensation according to the environment temperature, so as to ensure the stability of the signal transmission. After the signal converting and temperature compensating mechanism 300 converts the displacement signal into the rotation signal, the acoustic resonant frequency modulator and acceleration calculating mechanism 400 automatically converts the rotation signal into the displacement amplified signal, stimulates the resonance with the amplified displacement signal, picks up the resonant frequency signal, and calculates the acceleration by the change of the resonant frequency.

[0027] Example 2 On the basis of example 1, reference is made to Figures 2-5, single guide multi-electrode acceleration sensing mechanism 200 includes a first housing 210 located in the outer housing 100 inner wall bottom, both ends mounted in the first housing 210 inner wall both sides and surface has a plurality of groups of electrodes 220a single guide quartz beam 220 and with the single guide quartz beam 220 activity connected acceleration trigger assembly 230, the first housing 210 for easy support installation single guide quartz beam 220 and acceleration trigger assembly 230, single guide quartz beam 220 for matching a plurality of groups of electrodes 220a, conventional quartz accelerometer using the whole piezoelectric effect or capacitance change beam, here, distributed multi-group electrode 220a accurate "perception" of the local strain difference at different positions of the beam, each group of electrodes and its below quartz constitute a small piezoelectric unit, output proportional to the local strain weak voltage signal (V1, V2, V3, V4), "single guide" embodied in all electrodes share the same quartz beam as the main body of vibration and sensing.

[0028] In the present embodiment, with reference to Figures 2-5 , acceleration trigger assembly 230 includes a moving mass 230a located in the first housing 210 and located below the single guide quartz beam 220 and one end with the single guide quartz beam 220 bottom hinge and the other end with the moving mass 230a top hinge flexible hinge chain 230b, moving mass 230a for in as the carrier object of acceleration measurement, flexible hinge chain 230b for facilitating measurement start, allowing moving mass 230a under the acceleration along the sensitive axis (such as the Z axis) micro-displacement.

[0029] In the present embodiment, the specific workflow is as follows: when the measurement starts, the moving mass 230a moves on the Z axis under the connection action of the flexible hinge chain 230b, at the same time, a plurality of groups of electrodes 220a cooperate with the single guide quartz beam 220, when the acceleration acts on the sensitive axis, the inertial force makes the moving mass 230a move down / up, at this time the single guide quartz beam 220 occurs non-uniform bending deformation (different stress at different positions of the beam), thereby obtaining a plurality of groups of weak voltage signals proportional to the local strain, while generating the displacement signal of the moving mass 230a in the Z axis direction.

[0030] Embodiment 3 On the basis of embodiment 2, with reference to Figures 2-6, the signal conversion and temperature compensation mechanism 300 includes a second housing 310 located on top of the first housing 210 and sealed with the first housing 210, a balance wheel 320 movably mounted in the second housing 310, a temperature compensation bimetallic strip 330 coaxially arranged with the balance wheel 320, a signal conversion assembly 340 for converting the deflection signal of the balance wheel 320 into an electrical signal, and a first transmission assembly 350 having one end drivingly connected with the balance wheel 320 and the other end drivingly connected with the moving mass 230a, the second housing 310 is used to facilitate the installation of the balance wheel 320, the signal conversion assembly 340 and the first transmission assembly 350, at the same time, the first housing 210 and the second housing 310 are sealed with each other, thereby reducing the influence of temperature difference on the inside of the second housing 310, the balance wheel 320 is used to generate a rotation signal when rotating, the temperature compensation bimetallic strip 330 is composed of a special composite material sheet (such as quartz + a specific alloy), and the thermal expansion coefficient is accurately designed, when the environmental temperature changes, the bimetallic strip bends, actively adjusts the initial zero angle of the balance wheel 320, the signal conversion assembly 340 is used to convert the rotation signal into an electrical signal, and the first transmission assembly 350 is used to drive the balance wheel 320 to rotate by a corresponding angle when the moving mass 230a moves on the Z axis.

[0031] In this embodiment, referring to Figures 2-6 , the signal conversion assembly 340 includes a linear variable differential transformer core 340a located at one side edge of the balance wheel 320 and an LVDT coil group 340b mounted on the inner wall bottom of the second housing 310 and surrounding the motion trajectory of the linear variable differential transformer core 340a, the rigid connection of the linear variable differential transformer core 340a with the pendulum ensures zero return difference of displacement transmission, at this time the input quantity is: the rotation angle θ of the balance wheel 320 pushes the LVDT core to move linearly along the axial direction, the output quantity is: the LVDT secondary coil induced voltage difference ΔV = V1 - V2 is strictly proportional to the displacement of the core, at this time the electrical signal ΔV directly represents the angle θ of the balance wheel 320 (i.e. acceleration).

[0032] In this embodiment, referring to Figures 2-6 , the top of the moving mass 230a is provided with a connecting rod 230a-1 penetrating through the first housing 210 and the bottom of the second housing 310, for facilitating the installation of the connecting sawtooth plate 350b; Referring to Figures 2-6The first transmission assembly 350 includes a plurality of sawtooth blocks 350a evenly distributed on the circumferential side wall of the balance wheel 320 and a sawtooth plate 350b located on the top of the connecting rod 230a-1 and engaged with the plurality of sawtooth blocks 350a. The sawtooth blocks 350a are used to facilitate the rotation of the balance wheel 320 when the sawtooth plate 350b moves. The sawtooth plate 350b is used to facilitate the rotation of the balance wheel 320 under the engagement of the sawtooth blocks 350a when the moving mass 230a drives the connecting rod 230a-1 to move.

[0033] In the embodiment, the specific workflow is as follows: when the moving mass 230a drives the connecting rod 230a-1 to move on the Z axis, the connecting rod 230a-1 drives the sawtooth plate 350b to move, and the sawtooth plate 350b drives the balance wheel 320 to rotate by a corresponding angle under the engagement of the sawtooth blocks 350a. At the same time, the temperature compensation bimetallic strip 330 is bent and deformed according to the temperature change of the environment, thereby actively adjusting the initial zero angle of the balance wheel 320. The sensitivity (Young's modulus) of the quartz beam and the deformation of the temperature compensation bimetallic strip 330 are both affected by temperature. By carefully designing the material and structure of the bimetallic strip, the thermal deformation of the bimetallic strip is just enough to offset the change of the sensitivity of the quartz beam with temperature (and part of the bearing friction change), so that the relationship between the rotation angle of the balance wheel 320 and the acceleration remains stable in a wide temperature range. The LVDT outputs a temperature-compensated analog displacement signal that strictly corresponds to the acceleration; In addition, through the mechanical linkage of the single-guide multi-electrode acceleration sensing mechanism 200 and the signal conversion and temperature compensation mechanism 300, the linear strain / displacement signal is converted into an accurate rotation angle by a mechanical method, and a passive mechanical temperature compensation is integrated. At the same time, the engagement clearance (≈5 μm) between the sawtooth plate 350b and the sawtooth of the side wall of the balance wheel 320 forms a natural mechanical low-pass filter. When the moving mass 230a vibrates slightly due to high-frequency vibration noise (> 500 Hz), the energy is dissipated by the collision damping of the tooth side clearance, and cannot be transmitted to the balance wheel 320. In some vibration environments, false acceleration signals are avoided to trigger false actions.

[0034] Embodiment 4 On the basis of Embodiment 3, reference is made to Figures 2-8The acoustic resonant frequency modulator and acceleration measurement mechanism 400 includes a third housing 410 located on top of the second housing 310 and having a connection port 410b at the top; a resonant frequency generating component 420 installed on the top of the inner wall of the third housing 410; a drive component 430 installed inside the third housing 410 and drivenly connected to the resonant frequency generating component 420; and a second transmission component 440 with one end drivenly connected to the balance wheel 320 and the other end drivenly connected to the drive component 430. The third housing 410 is used to facilitate the installation of the resonant frequency generating component 420, the drive component 430, and the second transmission component 440. The resonant frequency generating component 420 generates a resonant frequency during operation, thereby obtaining a more reliable and stable signal by picking up the frequency. The drive component 430 triggers the resonant frequency generating component 420 to operate during operation. The second transmission component 440 drives the drive component 430 to operate when the balance wheel 320 rotates. In this embodiment, reference Figures 7-8 The resonant frequency generating component 420 includes tuning forks 420a symmetrically distributed on the top of the inner wall of the third housing 410 and V-shaped flexible bridges 420b connected at both ends to the arm ends of the two tuning forks 420a respectively. The tuning forks 420a are used to resonate at a fixed fundamental frequency F0 under preload and obtain different resonant frequencies after being compressed. The V-shaped flexible bridges 420b are used to attach to the arms of the tuning forks 420a to excite their resonance. The top of the tuning forks 420a has a thickened area and the end surface of the fork arm is polished to reduce air damping. The inner walls of the third housing 410 have receivers 410a on both sides to pick up the resonant frequency signal, which is then transmitted to the system to calculate the acceleration value.

[0035] In this embodiment, reference Figures 7-8 The drive assembly 430 includes a drive block 430a extending into the limiting grooves on both sides of the inner wall of the third housing 410, and a conical top block 430b located on top of the drive block 430a and corresponding to the V-shaped area of ​​the V-shaped flexible bridge 420b. The drive block 430a is used to drive the conical top block 430b at the top to move when it moves. The conical top block 430b is used to squeeze the V-shaped working area of ​​the V-shaped flexible bridge 420b when it moves, thereby generating external tension on both sides of the working area of ​​the V-shaped bridge. The tension is converted into axial tensile stress at the root of the fork arm, reducing the resonant frequency.

[0036] In this embodiment, reference Figures 2-6 The side wall of the balance wheel 320 is connected to the first pulley 320a via a pivot, which drives the second pulley 440b to rotate when it rotates. refer to Figures 2-8The second transmission assembly 440 comprises a cam 440a rotatably mounted in the housing and corresponding to the bottom of the driving block 430a, and a second pulley 440b located on the side wall of the cam 440a and connected with the first pulley 320a through a belt, the cam 440a is used to drive the driving block 430a to move along the limiting sliding groove when rotating, and the second pulley 440b is used to drive the cam 440a to rotate when rotating; With reference to Figures 2-8 The outer side wall of the third housing 410 is provided with a micro motor 410c connected with the side wall of the cam 440a through a rotating shaft, which is used to drive the cam 440a to rotate when working, and at the same time, the frequency of the tuning fork 420a is modulated, so as to complete self-calibration.

[0037] In this embodiment, the specific working process is as follows: when the balance wheel 320 rotates, the first pulley 320a is driven to rotate, the first pulley 320a drives the second pulley 440b to rotate when rotating, the second pulley 440b drives the cam 440a to rotate when rotating, the cam 440a drives the driving block 430a to move along the limiting sliding groove when rotating, and the driving block 430a drives the conical top block 430b to extrude the working area of the V-shaped flexible bridge 420b when moving, so that the two ends of the V-shaped flexible bridge 420b generate tension and then convert into axial tensile stress at the root of the fork arm, the resonance frequency is reduced, the applied stress changes the equivalent stiffness of the tuning fork 420a material, and thus the resonance frequency F of the tuning fork 420a is linearly modulated. ΔF = F - F0is proportional to the displacement of the moving mass block 230a, and further proportional to the acceleration, and the high-precision acceleration value can be obtained by measuring ΔF, in addition, at the end of each acceleration event (or when the device is started / periodically self-checked), the system actively controls the micro motor 410c to reversely drive the driving block 430a, so that it accurately passes through the whole stroke (simulates an acceleration input); the calibration principle is that the system records the frequency F change curve of the tuning fork 420a in this process, and compares it with the ideal frequency-displacement (i.e. frequency-acceleration) curve stored at the time of factory shipment and calibrated under standard conditions, any deviation (caused by aging, slight creep, residual temperature influence, etc.) can be detected and a real-time calibration correction coefficient can be generated and applied to subsequent actual measurement. The "multi-electrode" also plays a role in this structure: the multi-electrode signal (although weak) can assist in verifying the consistency of the start / end position of the driving block 430a displacement in the self-calibration mode; In addition, on the basis of the mechanical linkage of the signal conversion and temperature compensation mechanism 300 and the acoustic resonance frequency modulator and acceleration measurement mechanism 400, the strong modulation effect of stress on the quartz resonance frequency is used to convert the small mechanical displacement (acceleration) into a high-resolution and high-anti-interference frequency signal, and an online self-calibration mechanism based on known mechanical displacement is produced and integrated.

[0038] Although the present application has been described with reference to the embodiments above, various changes and modifications can be suggested to one skilled in the art, and it is intended that the present application encompass such changes and modifications as fall within the scope of the appended claims. Particularly, each feature disclosed in the description and / or the claims can be used in the combination with each of the features disclosed in the description and / or the claims, unless specifically stated otherwise. Therefore, the present application is not intended to be limited to the particular embodiments disclosed in the description and / or the claims.

Claims

1. A single island multi-electrode quartz accelerometer characterized by, The application relates to a single-guide multi-electrode acceleration sensing device. The single-guide multi-electrode acceleration sensing device comprises a shell (100) which is a one-piece structure; a single-guide multi-electrode acceleration sensing mechanism (200) which is installed at the inner bottom end of the shell (100), wherein the single-guide multi-electrode acceleration sensing mechanism (200) generates an acceleration signal and senses a displacement signal when working; a signal conversion and temperature compensation mechanism (300) which is installed in the shell (100) and located above the single-guide multi-electrode acceleration sensing mechanism (200), wherein when the single-guide multi-electrode acceleration sensing mechanism (200) senses an acceleration signal, the signal conversion and temperature compensation mechanism (300) automatically converts the displacement signal into a rotation signal and performs temperature compensation; and an acoustic resonance frequency modulator and acceleration measuring mechanism (400) which is installed in the shell (100) and located above the signal conversion and temperature compensation mechanism (300), wherein when the signal conversion and temperature compensation mechanism (300) converts an acceleration signal into a rotation signal, the acoustic resonance frequency modulator and acceleration measuring mechanism (400) is automatically driven to work, converts the rotation signal into a displacement signal, amplifies the displacement signal, excites resonance by using the amplified displacement signal, picks up a resonance frequency signal, and calculates the acceleration by the change of the resonance frequency. The single-guide multi-electrode and speed sensing mechanism comprises a first shell (210) located at the inner wall bottom of the shell (100), a single-guide quartz beam (220) with a plurality of electrodes (220a) installed at the inner wall of the first shell (210) and located at the two sides of the first shell (210), and an acceleration trigger assembly (230) movably connected with the single-guide quartz beam (220). The acceleration trigger assembly (230) comprises a moving mass (230a) located in the first shell (210) and below the single-guide quartz beam (220), and a flexible hinge chain (230b) hingedly connected at one end with the bottom of the single-guide quartz beam (220) and at the other end with the top of the moving mass (230a). The signal conversion and temperature compensation mechanism (300) comprises a second shell (310) located at the top of the first shell (210) and sealed with the first shell (210), a balance wheel (320) movably installed in the second shell (310), a temperature compensation bimetallic strip (330) coaxially arranged with the balance wheel (320), a signal conversion assembly (340) for converting the deflection signal of the balance wheel (320) into an electric signal, and a first transmission assembly (350) transmissionally connected at one end with the balance wheel (320) and at the other end with the moving mass (230a).

2. A single island multi-electrode quartz accelerometer according to claim 1, wherein The signal conversion assembly (340) comprises a linear variable differential transformer core (340a) located at the side edge of the balance wheel (320), and an LVDT coil group (340b) installed at the inner wall bottom of the second shell (310) and surrounding the motion track of the linear variable differential transformer core (340a).

3. A single island multi-electrode quartz accelerometer according to claim 2, wherein ​ 4. A single island multi-electrode quartz accelerometer according to claim 3, wherein ​ 5. A single island multi-electrode quartz accelerometer according to claim 4, wherein ​ 6. A single island multi-electrode quartz accelerometer according to claim 5, wherein The top of the moving mass (230a) is provided with a connecting rod (230a-1) penetrating the first shell (210) and the bottom of the second shell (310); The first transmission assembly (350) comprises a plurality of sawtooth blocks (350a) uniformly distributed on the circumferential sidewall of the balance wheel (320) and a sawtooth plate (350b) located on the top of the connecting rod (230a-1) and engaged with the plurality of sawtooth blocks (350a).

7. A single island multi-electrode quartz accelerometer according to claim 4, wherein The acoustic resonant frequency modulator and acceleration measurement mechanism (400) comprises a third shell (410) located on the top of the second shell (310) and having a connecting port (410b) on the top, a resonant frequency generating assembly (420) mounted on the top of the inner wall of the third shell (410), a driving assembly (430) mounted in the third shell (410) and in transmission connection with the resonant frequency generating assembly (420), and a second transmission assembly (440) in transmission connection with the balance wheel (320) at one end and with the driving assembly (430) at the other end.

8. A single island multi-electrode quartz accelerometer according to claim 7, wherein The resonant frequency generating assembly (420) comprises tuning forks (420a) symmetrically distributed on the top of the inner wall of the third shell (410) and V-shaped flexible bridges (420b) connected with the arm ends of the two tuning forks (420a) respectively, the top of the tuning fork (420a) has a thickened area and the terminal surface of the fork arm is polished, and the inner wall of the third shell (410) has receivers (410a) on both sides for picking up resonant frequency.

9. A single island multi-electrode quartz accelerometer according to claim 8, wherein, The driving assembly (430) comprises a driving block (430a) extending into the limiting sliding groove on both sides of the inner wall of the third shell (410) and a conical top block (430b) located on the top of the driving block (430a) and corresponding to the V-shaped area of the V-shaped flexible bridge (420b).

10. A single island multi-electrode quartz accelerometer according to claim 9, wherein The sidewall of the balance wheel (320) is connected with a first pulley (320a) through a rotating shaft; The second transmission assembly (440) comprises a cam (440a) rotatably mounted in the shell and corresponding to the bottom of the driving block (430a) and a second pulley (440b) located on the sidewall of the cam (440a) and connected with the first pulley (320a) through a belt; The outer sidewall of the third shell (410) is provided with a micro motor (410c) connected with the sidewall of the cam (440a) through a rotating shaft.

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