79 results about "Electro mechanical coupling" patented technology

An acoustic resonator with improved quality factor and electro-mechanical coupling is disclosed. In one embodiment, the acoustic resonator includes an acoustic mirror formed on the top surface of a substrate or in the substrate, a first electrode having a end portion, formed on the acoustic mirror, a piezoelectric layer formed on the first electrode; and a second electrode formed on the piezoelectric layer, where at least one of the first electrode and the second electrode and the piezoelectric layer define an air gap in a region that overlaps the end portion of the first electrode. In one embodiment, a dielectric film is deposited on the surface of the end portion of the first electrode to form completely planarized surface before the piezoelectric layer deposition. In another embodiment, an air gap between the second electrode and the piezoelectric layer, so that the piezoelectric coupling in the end portion area of the first electrode is minimally contributed into the whole resonator.

The invention relates to a body wave resonator and a processing method thereof. The body wave resonator comprises an acoustic mirror arranged on or embedded in a substrate and provided with a first edge and a second edge, a dielectric layer which is arranged on the substrate and in full contact with the two edges of the acoustic mirror, a first electrode which is arranged on the acoustic mirror and composed of a first terminal part, a second terminal part and a main part which is arranged between the first and the second terminal parts, a piezoelectric layer which is arranged on the first electrode and composed of a main part, a first terminal part and a second terminal part, and a second electrode which is arranged on the piezoelectric layer and consists of a main part and a second part, wherein the main part is located above the main part of the piezoelectric layer and connected with the second part, so that the connected joint of the main part and the second part is arranged between the first edge and the second edge of the acoustic mirror, and an air gap is formed between the second part of the second electrode and the first terminal part of the piezoelectric layer. The body wave resonator has simple structure and convenient processing, and can improve the quality factor, effective electro-mechanical coupling factor and static discharge resistance capacity.

The invention discloses a cascade and parallel piezoelectric composite material-based cylindrical transducer, which comprises a support with an underpan, an annular backing, an end cover and a plurality of wafers, wherein the wafers are cascade and parallel piezoelectric composite wafers, are uniformly arranged on the outer side of the annular backing along the periphery and are polarized along the radial direction of the ring; insulating washers are cushioned on and under a tubular sensitive element consisting of the backing and the wafers; the tubular sensitive element is sleeved and fastened on the underpan of the support; and the end cover is fixed at the upper end of the support and on the insulating washer on the sensitive element. The transducer adopts a multi-wafer annular array as the sensitive element, the vibration of the wafers adopts a thickness model, the working frequency is higher than the radial vibration frequency of a round tube, and the high-frequency sound wave emission can be realized; moreover, because the wafers are mode of the cascade and parallel composite material, the electro-mechanical coupling factor of the composite material is high, the frequency band thereof is broad, and the transducer has high sensitivity and broad working frequency band; therefore, the transducer has the characteristics of high frequency, high sensitivity, broad band and level omnidirection.

A manually driven electronic deadbolt assembly configured with an electro mechanical coupling mechanism to selectively couple a manually operable bezel to a torque blade for operation of a deadbolt mechanism. The electro-mechanical coupling mechanism is configured such that in a locked condition the manually operable bezel is drivably decoupled from the torque blade, such that the manually operable bezel is free-spinning when rotated so as to be rendered incapable of rotating the torque blade to operate the deadbolt mechanism. Also, the electro-mechanical coupling mechanism is configured to drivably couple the manually operable bezel to the torque blade when a valid code is input to a code input mechanism to facilitate the unlocked condition, such that a rotation of the manually operable bezel effects a rotation of the torque blade to operate the deadbolt mechanism.

The present invention provided a thin film piezoelectric resonator that has an electro-mechanical coupling coefficient kt2and a Q value which are both large and is provided with a lower electrode whose film thickness can be easily controlled, and to provide its manufacturing method. The thin film piezoelectric resonator is equipped with a substrate 11, the lower electrode 14 which is mechanically held on the substrate 11, facing partially toward the hollow part of the substrate 11, a piezoelectric material 15 which is arranged on the lower electrode 14 so as to include it all inside the region occupied by the piezoelectric material 15 itself, an upper electrode 16 located on the piezoelectric material 15, a relay electrode 13 which is located on the border of the region occupied by the piezoelectric material 15 on a plane pattern between the substrate 11 and the piezoelectric material 15 and connected to the lower electrode 14 inside the region occupied by the piezoelectric material 15, and lower electrode wiring 17 which is extended outward from the border of the region occupied by the piezoelectric material 15 and connected to the relay electrode 13.

The invention discloses a method for measuring mental hull fatigue life on the force/ electrical coupling field, which deposits the mental hull on the polyimide soft base plate. The minimum tensile load makes the mental hull to generate yield force, the soft base plate is at elastic deforming stage, when loading it, and the mental hull inner part will generate the compressive stress to achieve the mental hull drag-press fatigue circulating load. The electrical loading exerts method of the mental hull uses cylinder contact device. It exerts the circulating force and the electrical loading on the mental hull and uses the mutation of the mental hull shift amplitude with permanent loading amplitude or on the control of the loading amplitude to hand the forming of the mental fatigue defection and shows the fatigue life.

This invention provides a piezoelectric ceramic composition that does not contain lead, can be sintered at a normal pressure and is excellent in at least one of a piezoelectric constant, an electro-mechanical coupling coefficient, a dielectric loss, a relative dielectric constant and a Curie point, its production method, and a piezoelectric device and a dielectric device each utilizing the piezoelectric ceramic composition. The invention relates to a piezoelectric composition expressed by the general formula {Li_x(K_1−yNa_y)_1−x}(Nb_1−zSb_z)O₃, each of x, y and z respectively falling within composition ranges of 0≦x≦0.2, 0≦y≦1.0 and 0≦z≦0.2 (with the exception of x=z=0), and its production method. The invention further relates to a piezoelectric device having a piezoelectric body formed of the piezoelectric ceramic composition described above and a dielectric device having a dielectric body formed of the piezoelectric ceramic composition described above.

The invention discloses an electro-mechanical coupling power-assisted steering system for a plug-in type hybrid power bus and a control method thereof. According to the system, the characteristics of the plug-in type hybrid power bus are fully utilized, electro-mechanical coupling of an engine steering pump power-assisted steering system and an electric power-assisted steering system is achieved, and vehicle operation safety, whole bus energy saving and the bus operation requirements in a power battery failure mode are effectively achieved. According to the method, the characteristics of a configuration structure of the plug-in type hybrid power bus are fully utilized, the traditional engine steering pump power-assisted steering system and the electric power-assisted steering system are effectively coupled, double-channel power-assisted steering is achieved, the adopted control method can guarantee timely and reasonable work of traditional power-assisted steering and electric power-assisted steering, reliability of the whole bus is improved, energy consumption is reduced, and the requirements of mass production are met.

The invention provides a sandwich type piezoelectric driving track traveling device and a working method thereof. The device comprises a metal track, two annular components and a variable cross-section sandwich type piezoelectric transducer, wherein the annular components are arranged at two ends of the variable cross-section sandwich type piezoelectric transducer; and the variable cross-section sandwich type piezoelectric transducer consists of four sets of piezoelectric ceramic components fixed between two sets of variable cross-section beams and a metal connecting block. According to the sandwich type piezoelectric driving track traveling device and the working method thereof, by stimulating piezoelectric ceramic pieces, a longitudinal vibration mode and a bending vibration mode are stimulated on the variable cross-section beams, and two in-plane bending vibration modes with pi/2 phase difference in space are presented on the annular components respectively, so that traveling waves rotating along the peripheral direction are coupled on the annular components, mass points on the outer surfaces of the annular components carry out micro-amplitude elliptical motions and drive metal track to move through the action of friction, and the device has the advantages of compact structure, large force (torque) weight ratio, high environmental suitability, structure form flexibility, high speed, high electro-mechanical coupling efficiency and the like.

The invention relates to a piezoelectric crystal element and belongs to the field of crystal elements. The piezoelectric crystal element comprises a piezoelectric crystalline material (1), an electrode layer (2) and a lead (3). A chemical formula of the piezoelectric crystal material is A3+xB1+yAl3+zSi2+mO14+n, wherein x is more than or equal to -0.2 and less than or equal to 0.2; y is more than or equal to -0.2 and less than or equal to 0.2; z is more than or equal to -0.2 and less than or equal to 0.2; m is more than or equal to -0.2 and less than or equal to 0.2; n is more than or equal to -1.4 and less than or equal to 1.4; A is Ca, Sr or combination of the two elements; and B is one of Ta, Nb or Sb, or combination of more of the three elements. The maximum service temperature of the piezoelectric crystal element can reach 1,000 DEG C; and the piezoelectric crystal element has the characteristics of large high temperature electrical resistivity, large piezoelectric coefficient, large electro-mechanical coupling factor, no phase change from the room temperature to a melting point, low price and the like.

An embodiment of the present invention provides a method, comprising reducing the losses due to electro-mechanical coupling and improving Q in a multilayered capacitor by placing a first capacitor layer adjacent at least one additional capacitor layer and sharing a common electrode in between the two such that the acoustic vibration of the first layer is coupled to an anti-phase acoustic vibration of the at least one additional layer.

The invention discloses a method for quickly determining cylindrical conformal array antenna structure tolerance based on electro-mechanical coupling. The method comprises the following steps: determining structure parameters and electromagnetic working parameters of a cylindrical conformal array antenna; respectively giving circumferential position tolerance and axial position tolerance of an initial array element, and determining a circumferential position error random quantity and an axial position error random quantity of all array elements in an array plane; calculating new positions of the array element when an error exists; establishing an array element rectangular coordinate system and an array element spherical coordinate system, and calculating array element directional diagrams under the array element rectangular coordinate system and an array rectangular coordinate system; determining an array element excitation amplitude and a phase according to apertural face weighting distribution; calculating a spatial phase difference of each array element at a target; calculating antenna electrical performance parameters by utilizing a cylindrical conformal array antenna electro-mechanical coupling model when the error exists; judging whether the antenna electrical performance under the structure tolerance condition meets a requirement. According to the method, the problems about quickly determining a cylindrical conformal array antenna structure scheme and distributing the antenna structure tolerance are effectively solved; the method can be used for guiding the evaluation of an antenna structure scheme.

The invention provides a bend-twist coupling type piezoelectric driving track traveling device and a working method thereof. The device comprises a metal track, two annular components and a variable cross-section piezoelectric transducer, wherein the annular components are arranged at two ends of the variable cross-section piezoelectric transducer; the variable cross-section piezoelectric transducer comprises a plurality of sets of piezoelectric ceramic pieces, two pre-tightening wedge blocks and a variable cross-section beam; and the piezoelectric ceramic pieces are arranged in a certain order and are fixed in a groove of the variable cross-section beam through the pre-tightening wedge blocks. According to the bend-twist coupling type piezoelectric driving track traveling device and the working method thereof, by stimulating the piezoelectric ceramic pieces, a torsional vibration mode and a bending vibration mode are stimulated on the variable cross-section beam, so that a traveling wave, with n (n being greater than or equal to 2) wave crests and wave troughs shown all together, rotating along the peripheral direction is coupled on the annular components, the mass points on the outer surfaces of the annular components carry out micro-amplitude elliptical motions and drive the metal track to move through the action of friction, and the device has the advantages of compact structure, large force (torque) weight ratio, high environmental suitability, structure form flexibility, high speed, high electro-mechanical coupling efficiency and the like.

The invention discloses a high-Curie-temperature piezoelectric ceramic. The general formula of the piezoelectric ceramic is (BiYb)(1-x)PbxTiyZr(x-y)O(3+z)mol%A, wherein x is equal to 0.91-0.98, y is equal to 0.45-0.68, z is equal to 0.05-5, and A is a modified element. The invention also provides a method for preparing the piezoelectric ceramic. The piezoelectric ceramic prepared by using the method has relatively high Curie temperature, relatively high piezoelectric constant, relatively low dielectric loss, relatively high electro-mechanical coupling coefficient, mechanical quality factors with relatively wide variable range and the like, and can solve the problems that an existing piezoelectric material can difficultly have relatively high Curie temperature and relatively high piezoelectric performance at the same time, and integrated electrical parameters cannot meet the use requirements of specific piezoelectric devices. The high-Curie-temperature piezoelectric ceramic disclosed by the invention has the characteristics that the high-Curie-temperature piezoelectric ceramic is simple and stable in process, does not need special equipment, is relatively low in cost, convenient for large-scale industrial production and the like, and can be applied to various corresponding high-temperature piezoelectric devices.

The invention discloses a multi-working-condition active vibration reduction control method for a hybrid power system based on vibration reduction waveforms, and relates to the field of new energy hybrid power system electronic control. According to the method, fluctuation torques on an electromechanical coupling shaft of the hybrid power system in different operation states are tested in a test bench, and vibration reduction compensation waveforms corresponding to different working conditions are designed in an off-line mode; a crankshaft position sensor and a rotary transformer are used for collecting signals of positions, rotating speeds and the like of an engine crankshaft and a motor rotor in real time, and the state and working condition points of a hybrid power system are judged online in real time in combination with an engine throttle target instruction; and the amplitude and phase of the fluctuation torque are estimated, a prefabricated vibration reduction compensation waveform is matched, the motor is enabled to superpose the torque of the vibration reduction waveform on the target torque to realize active vibration reduction, and the vibration reduction waveform is switched in real time along with the change of working conditions. The torque ripple suppression of the hybrid power system under multiple working conditions can be realized according to the operation state, and the driving comfort and the safety and reliability of parts are improved.

This invention provides a piezoelectric ceramic composition that does not contain lead, can be sintered at a normal pressure and has a high electro-mechanical coupling coefficient and a small dielectric loss, its production method, and a piezoelectric device utilizing the piezoelectric ceramic composition. The invention relates to a piezoelectric composition containing a compound expressed by the general formula {Li_x(K_1-yNa_y)_1-x}(Nb_1-zTa_z)O₃, each of x, y and z respectively falling within composition range of 0≦x≦0.2, 0≦y≦1.0 and 0≦z≦0.4, as its main component, and further containing nickel or a nickel-containing compound. To provide a piezoelectric device that does not contain lead, can be sintered at a normal pressure and has a high electro-mechanical coupling coefficient Kp and a small dielectric loss, the piezoelectric ceramic composition of the invention is expressed by the general formula {Li_x(K_1-yNa_y)_1-x}(Nb_1-z-nTa_z(Mn_0.5W_0.5)_nO₃, each of x, y, z and n respectively falling within a composition range of 0≦x≦0.2, 0≦y≦1.0, 0≦z≦0.4 and 0<n≦0.1.

The present invention provides a microcosmic and nano-scale electro-mechanical coupling feature measurement device based on an AFM (Atomic Force Microscope). The device comprises a piezoelectric actuator, an AFM probe, a conductive second probe, a laser emitter, a microscope, a detector and a data processing center; two ends of a flexible and elastic conductive sample are installed on a fixed mount through clamps; the movable piezoelectric actuator is installed on the fixed mount; the fixed mount is provided with the AFM probe and the conductive second probe, the AFM probe is in contact with the surface of the flexible and elastic conductive sample through motion, and the conductive second probe is in contact with the surface of the flexible and elastic conductive sample; and an AFM is internally provided with the laser emitter and the detector, and the laser emitter is configured to emit signals. The microcosmic and nano-scale electro-mechanical coupling feature measurement device based on the AFM and the detection method thereof can perform test of the nano-scale conductive performance and mechanical load coupling relation so as to dynamically reflect the relation of the mechanical loads, the structures and the material performances of test samples under the electro-mechanical coupling action in real time.

The invention discloses a method for preparing a high-orientation PZT piezoelectric thin film. The method is characterized by comprising the following steps of: sequentially growing a SiO2 layer, a Ti layer, a Pt layer, a PbTiO3 layer, a PZT layer (spin coating or sputtering) and a top electrode layer on a silicon wafer, wherein the PbTiO3 layer is abbreviated as a PT layer, used as a seed crystal layer or a seed layer and made by MOCVD, sputtering or MBE method; and performing rapid annealing process (RTP) on the PT layer and the PZT layer once or several times during the growth of the PT and PZT. Compared with a conventional silicon/silicon dioxide/Pt/PZT/top electrode structure, the PZT piezoelectric thin film prepared by the method has the advantages of high preferred orientation and high electro-mechanical coupling coefficient.

The invention discloses a braille touch screen device based on IPMC driving. The braille touch screen device comprises at least one braille touch unit, wherein the braille touch unit is formed in such a manner that six contacts are packaged in three rows and two columns, and each contact comprises a support plate, a pair of electrodes, an IPMC driver, a VHB film and a cover plate; the support plate is a circular thin plate; the electrodes are annular electrode sheets with side ears and are arranged on the end part of the support plate; the IPMC driver is a circular sheet and comprises an edge constraint area close to the peripheral part and free areas of other parts, and the edge constraint area is arranged between the two annular electrode sheets; the VHB film is a circular film; the cover plate is an annular thin plate, the lower end of the cover plate is bonded to the VHB film, and the cover plate covers the IPMC driver; and the edge of the cover plate is pasted to the edge of the support plate, and the distance between the VHB film on the lower end of the cover plate and the support plate is not larger than the thickness sum of the two electrodes and the IPMC driver. The electro-mechanical coupling performance of the IPMC driver is utilized, and the braille touch screen device can be used for reading Braille and can also be used as a braille input device.

The invention relates to the field of sensors, and discloses a preparation method for a polymer-based composite flexible piezoelectric sensor. According to the method, an ultrafine lead zirconate titanate ceramic and a zinc oxide nanorod array are firstly prepared, the rod array is then implanted into a mold, so that a polymer-based piezoelectric material is prepared, the mixture of epoxy resin and styrene-butadiene-styrene block copolymer is injected into the mold, and after polymer base solidification, by polarization, the polymer-based composite flexible piezoelectric sensor is obtained. The polymer-based composite flexible piezoelectric sensor has more excellent detection performance, the flexibility of the used polymer material is good, a large and uniform film can be produced, the piezoelectric coefficient and the electro-mechanical coupling coefficient are low, a composite material with certain piezoelectric performance can be prepared after combination, the defects of both areovercome, the polymer-based composite flexible piezoelectric sensor has high piezoelectricity, low brittleness, low density and low dielectric coefficient, moreover, large-area sheets and products with complex shapes can be easily produced, the production process is simple, and the cost is low.