Cantilever beam type flexoelectric acceleration sensor and method for measuring acceleration

An acceleration sensor, cantilever beam technology, applied in the sensor field, can solve the problems of small strain gradient, difficult to measure accurately, weak electrical signal, etc., to avoid the deformation of metal elastic elements, easy to measure accurately, and to select a wide range of effects.

Inactive Publication Date: 2019-03-22
XI AN JIAOTONG UNIV
9 Cites 4 Cited by

AI-Extracted Technical Summary

Problems solved by technology

However, due to the small deformation of the metal elastic element after being pressed, the strain gradient of this kind of flexoelectric pressure sensor is also small, and the electrical signal generated is weak, so it is difficult to measure accurately
Secondly, the change in ...
View more

Abstract

The invention discloses a cantilever beam type flexoelectric acceleration sensor and a method for measuring acceleration. The cantilever beam type flexoelectric acceleration sensor comprises a plurality of flexoelectric dielectric materials, metal electrodes, epoxy resin, an upright column, a mass block and two lead wires. The flexoelectric dielectric materials are stacked on one another, and themetal electrodes are arranged on the upper surfaces and the lower surfaces of the flexoelectric dielectric materials; every two adjacent metal electrodes are solidified by the epoxy resin; the uprightcolumn is fixed to one end of each flexoelectric dielectric material; the mass block is adhered at the other end of the corresponding flexoelectric dielectric material; the lead wires are arranged between the metal electrodes in a serially connected manner, and the other ends of the two lead wires are connected with two external metal electrodes; a packaging protection cover and a base are adhered with each other, and the flexoelectric dielectric materials, the metal electrodes, the mass block and the lead wires are sealed in the packaging protection cover and the base. The cantilever beam type flexoelectric acceleration sensor and the method have the advantages that the magnitude of the acceleration can be measured by the aid of linear relations between strain gradient of the flexoelectric dielectric materials under the effect of inertia force of the mass block along the thickness directions and electric charge generated on the basis of flexoelectric effects, and accordingly vibration can be measured.

Application Domain

Acceleration measurement using interia forces

Technology Topic

PhysicsInertia force +9

Image

  • Cantilever beam type flexoelectric acceleration sensor and method for measuring acceleration
  • Cantilever beam type flexoelectric acceleration sensor and method for measuring acceleration
  • Cantilever beam type flexoelectric acceleration sensor and method for measuring acceleration

Examples

  • Experimental program(1)

Example Embodiment

[0039] The present invention will be further described in detail below with reference to the drawings and specific embodiments.
[0040] Such as figure 1 As shown, a cantilever beam type flexural electrical acceleration sensor of the present invention includes a plurality of stacked flexural dielectric materials 6, and metal electrodes 8 are respectively provided on the upper and lower surfaces of the flexural dielectric material 6; The epoxy resin 7 of the adjacent metal electrode; the post 3 fixed at one end of the flexural dielectric material 6, a plurality of stacked flexural dielectric materials 6 and the metal electrodes 8 and epoxy resin 7 arranged on one end are fixed On the column 3, a cantilever beam is formed; the mass 9 is bonded to the other end of the flexural dielectric material 6, which is the free end of the cantilever beam; the lead 5 of the metal electrode is connected in series, and the two leads at both ends of the metal electrode 8 are connected to two The external metal electrode 1 is connected; the packaging protective cover 2 and the base 4 are bonded together to seal the flexural dielectric material 6, the external metal electrode 1, the mass 9 and the lead 5 inside.
[0041] As a preferred embodiment of the present invention, the left metal electrode 8 is an evaporated gold electrode.
[0042] As a preferred embodiment of the present invention, the lead 5 and the metal electrode 8 and the external metal electrode 1 are connected by wire bonding.
[0043] As a preferred embodiment of the present invention, the flexural dielectric material 3 is three non-polarized barium strontium titanate beams with a thickness of 1 mm.
[0044] As a preferred embodiment of the present invention, the packaging protective cover 2 is a square epoxy resin shell, the base 4 is a square alloy steel, the mass 9 is a tungsten block, and the material of the column 3 is alloy steel.
[0045] As a preferred embodiment of the present invention, the external metal electrode 1 is two copper rods.
[0046] When the test piece located under the sensor vibrates, the mass 9 bonded to the free end of the cantilever beam causes the cantilever beam to bend, resulting in a larger strain gradient along the thickness direction. For a rectangular cross-section cantilever beam, the polar moment of inertia I is
[0047]
[0048] Among them, b is the total width of the cantilever beam, h is the total thickness of the cantilever beam; set the total length of the cantilever beam as l, and according to the related theory of elasticity, the strain (ε) of the cantilever beam is along the thickness direction (x) and the length direction ( The distribution of z) is
[0049]
[0050] Where F is the force applied by the free end of the cantilever beam, and E is the elastic modulus of the flexural dielectric material. So at any length, the expression of the strain gradient along the thickness direction is
[0051]
[0052] The expression of the strain gradient generated by the entire cantilever beam is
[0053]
[0054] Where F is the inertial force of the mass block, and its expression is
[0055] F=ma
[0056] Among them, m is the mass of the mass and a is the required acceleration.
[0057] and so,
[0058]
[0059] The cantilever beam produces a flexural electric effect along the thickness direction and produces a polarized charge. The expression is:
[0060]
[0061] Where μ is the flexural electrical coefficient, P is the polarization caused by the strain gradient caused by the flexural electrical effect, Q is the output charge of the external metal electrode 1, and A is the surface area of ​​the flexural dielectric material.
[0062] and so,
[0063]
[0064] Derived from the above formula, the acceleration expression is
[0065]
[0066] It can be seen from the above formula that as long as the output charge value of the external metal electrode 1 is measured, the linear relationship between the strain gradient generated by the flexural dielectric material under the action of the mass inertial force and the charge generated based on the flexural electrical effect, It can accurately measure the acceleration of the mass, so as to realize the measurement of the vibration of the specimen.

PUM

PropertyMeasurementUnit
Thickness1.0mm

Description & Claims & Application Information

We can also present the details of the Description, Claims and Application information to help users get a comprehensive understanding of the technical details of the patent, such as background art, summary of invention, brief description of drawings, description of embodiments, and other original content. On the other hand, users can also determine the specific scope of protection of the technology through the list of claims; as well as understand the changes in the life cycle of the technology with the presentation of the patent timeline. Login to view more.

Similar technology patents

Imaging apparatus and method for displaying zoom information

ActiveUS20080055429A1wide selection
Owner:CASIO COMPUTER CO LTD

Method for feeding back initial absolute position of motor, apparatus and encoder frequency-dividing apparatus

ActiveCN105676685Alow costwide selection
Owner:深圳市雷赛软件技术有限公司 +1

Measurement and analysis change-over device for vehicle-mounted antenna

InactiveCN107132426AEasy to measure accuratelyImprove work efficiency
Owner:SHANGHAI DELCO ELECTRONICS & INSTR

Method for preparing 'water-in-water' emulsion paper-making retention aid

InactiveCN104448132AEasy to automateEasy to measure accurately
Owner:MCC PAPER YINHE

Breeding method used for two-line sterile line of Southeast Asia hybrid rice

InactiveCN109042293AWide selectionfull rice grains
Owner:ANHUI HUARUN BIOTECH

Frequency type photoelectric converter, device and method

ActiveCN112985594AEasy to measure accuratelyHigh precision
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA

Classification and recommendation of technical efficacy words

  • Easy to measure accurately
  • wide selection

Measurement and analysis change-over device for vehicle-mounted antenna

InactiveCN107132426AEasy to measure accuratelyImprove work efficiency
Owner:SHANGHAI DELCO ELECTRONICS & INSTR

Method for preparing 'water-in-water' emulsion paper-making retention aid

InactiveCN104448132AEasy to automateEasy to measure accurately
Owner:MCC PAPER YINHE

Frequency type photoelectric converter, device and method

ActiveCN112985594AEasy to measure accuratelyHigh precision
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA

Imaging apparatus and method for displaying zoom information

ActiveUS20080055429A1wide selection
Owner:CASIO COMPUTER CO LTD

Method for feeding back initial absolute position of motor, apparatus and encoder frequency-dividing apparatus

ActiveCN105676685Alow costwide selection
Owner:深圳市雷赛软件技术有限公司 +1

Breeding method used for two-line sterile line of Southeast Asia hybrid rice

InactiveCN109042293AWide selectionfull rice grains
Owner:ANHUI HUARUN BIOTECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products