459 results about "Piezoelectric transduction" patented technology

A method for lysing fat cells using a multi-element, phased array piezoelectric transducer, the method comprising: providing a multi-element, phased array piezoelectric transducer comprising a single unitary piece of piezoelectric material having a plurality of electrode elements being formed as a segmented conductive layer on at least one surface of the piezoelectric material, each segment of the conductive layer being associated with an individual transducer element; positioning the transducer over a body of a patient, in proximity to a target volume containing fat cells; causing at least some of the transducer elements to emit ultrasound energy by exciting their associated electrode elements with high frequency voltages, the ultrasound energy having a power density at the target volume which is higher than a cavitation threshold; and spatially steering the ultrasound energy across the target volume by controlling the excitation of electrode elements in the time domain, thereby inducing cavitation in fat cells contained in the target volume.

The present invention relates to the design of piezoelectric transducer subassemblies and systems primarily intended for medical and dental applications. The invention also provides transducer subassemblies and systems with improved performance and a capability to operate more efficiently in torsional or a combined longitudinal-torsional mode of vibration. The invention enables the size and weight of torsional mode transducers to be reduced. Additionally, the electrical characteristics of these transducer systems are improved, thus enabling the transducer end effector to deliver more power to the operative site.

The invention relates to a board band piezoelectric generating set. A plurality of socle beams L1, L2, L3 are divided into two groups; one end of each socle beam is fixed and the other end keeps free; the socle beams keep parallel with each other; a crossing section is arranged between the two groups of the socle beams; wherein, the socle beam consists of piezoelectric transduction elements (34, 36), a down-lead (31), a metal block (32) and electrodes (33, 35, 37). The electrodes and the transduction elements are alternately arranged; the down-lead (31) is arranged at the fixed end of the socle beam; the metal block (32) is arranged at the free end of the socle beam. The sizes and the structures of the socle beams L1, L2, L3 are different, the manufacture materials of the piezoelectric transduction elements are different and the qualities of the metal blocks are different, therefore, the resonance frequency of each beam is different. The two groups of the socle beams L1, L2, L3 are arranged in an interdigital structure in plane or an interdigital structure in space. The board band piezoelectric generating set can absorb the mechanical vibration or noise of a plurality of frequency components in the environment and realize the transformation from mechanical energy to electricity energy by the piezoelectric transduction elements so as to increase the generating capacity and improve the generating efficiency.

The present invention provides an anti-icing / de-icing system and method using ultrasound waves for an external surface of a structure likely to be iced, such as an aircraft wing or engine nacelle, and such a structure incorporating this system. The system comprises a plurality of piezoelectric transducers with which the structure is fitted, opposite this external surface, and this system is such that it comprises means of scanning at least one matrix of elementary meshes predefined in this surface in relation to an even arrangement of a group of these transducers, these scanning means being able to focus the waves emitted by all or some of the transducers of the or each group on these meshes one after the other, via signal summing means coupled to these scanning means and able to produce, for each mesh, a summation of the signals obtained from the transducers emitting these waves.

An electrostatic transducer for micromechanical resonators, in which the electrode gaps are filled with a dielectric material having a much higher permittivity than air. This internal electrostatic transducer has several advantages over both air-gap electrostatic and piezoelectric transduction; including lower motional impedance, compatibility with advanced scaled CMOS device technology, and extended dynamic range. In one aspect, in order to minimize energy losses, the dielectric material has an acoustic velocity which is matched to that of the resonator material. Internal electrostatic transduction can be adapted to excite and detect either vertical modes (perpendicular to the substrate) or lateral modes (in the plane of the substrate). Its increased transduction efficiency is of particular importance for reducing the motional resistance of the latter.

An electrical energy generator with improved efficiency has a base on which is mounted an elastically deformable micromechanical element that has a section that is free to be displaced toward the base. An absorber of radioactively emitted particles is formed on the base or the displaceable section of the deformable element and a source is formed on the other of the displaceable section or the base facing the absorber across a small gap. The radioactive source emits charged particles such as electrons, resulting in a buildup of charge on the absorber, drawing the absorber and source together and storing mechanical energy as the deformable element is bent. When the force between the absorber and the source is sufficient to bring the absorber into effective electrical contact with the source, discharge of the charge between the source and absorber allows the deformable element to spring back, releasing the mechanical energy stored in the element. An electrical generator of improved efficiency includes a first energy source comprising a piezoelectric transducer secured to the deformable element to convert the released mechanical energy to electrical energy. A second energy source comprises a betavoltaic cell carried on the deformable element or electron collector cantilever beam to provide a direct current (DC) power output that can be added to the piezo-electric circuit's alternating current (AC) power output, such that there is a continuous power output that can be used to provide power to electronic circuits.

An ultrasonic transducer is described for use in a fluid medium. The ultrasonic transducer includes at least one piezoelectric transducer element and at least one matching element for promoting an oscillation injection between the piezoelectric transducer element and the fluid medium. The ultrasonic transducer also includes a housing (112), the piezoelectric transducer element being inserted in the housing. The housing has at least one opening facing the fluid medium, the matching element being inserted at least partially into the opening. The ultrasonic transducer also has at least one sealing element, which seals at least one intervening space between the matching element and the housing in such a way that an inner space of the housing is at least largely sealed from the fluid medium.

A piezoelectric transducer for harvesting ambient vibration energy is made up of a curved substructure beam, two half-tube piezoelectric elements and a mass block. One end of the beam is fixed on a vibration base and the other end is attached with the mass block. Two half-tube piezoelectric elements are affixed on the surface of the curved substructure beam. The present invention has a high energy transformation efficiency and a low resonance frequency. It can be applied in implantable devices, wearable electronics and wireless sensor networks.

A downhole tool includes circumferentially spaced and / or angled transducer elements. In one embodiment a standoff sensor has at least three piezoelectric transducer elements, at least a first element of which is configured to both transmit and receive ultrasonic energy. At least second and third of the elements are configured to receive ultrasonic energy transmitted by the first element in pitch catch mode. An electronic controller is configured to calculate a standoff distance from the ultrasonic waveforms received at the first, the second, and the third piezoelectric transducer elements. The controller may further be configured to estimate the eccentricity of a measurement tool in the borehole. Exemplary embodiments of the invention may improve borehole coverage and data quality and reliability in LWD caliper logging. In particular, the invention may advantageously reduce or even eliminate blind spots when logging eccentric bore holes.

An improved method and apparatus for producing an extremely fine micron and sub-micron size water mist using an electronic ultrasonic device that produces the mist at ambient-pressure and delivering the mist for application in suppressing fire. A piezoelectric transducer is arranged to produce a water mist having at least a portion of sub-micron size droplets. The water mist is produced by high frequency pressure waves or ultrasonic waves of predetermined or variable frequency, including frequencies which may exceed 2.5 MHz. The water mist is directed to a firebase to be self-entrained by the fire's flame. The momentum provided the water mist in directing the mist is minimized to enhance the ability of the fire to entrain the mist, and the flow of the carrier medium is usually directed tangentially about the water fountain creating the mist. Further, the throughput and concentration of the mist is controlled to ensure that the entrained mist will be sufficient to cool and suppress the fire. The water mist may be effectively utilized for mitigating blast and reducing over pressures. The fine water mist may also be utilized for humidification because of its fast vaporization and efficient cooling behavior. The apparatus may be modified in its physical design and direction of output, and the method may be modified by adjusting the throughput of mist, composition of mist, concentration of mist, and momentum of mist, whereby fire may be suppressed under many different scenarios.

Composite materials cure monitoring system and method based on the use of piezotransducers that can be activated by external signals and that, as a result of this activation, can generate elastic waves that can be detected by same, or distinct, piezotransducers distributed over the structure. The received signals are, then, processed by a dedicated acquisition and processing system with the objective to control the composite material cure process.

An imaging system includes: a transceiver cell for generating a pressure wave and converting an external pressure wave into an electrical signal; and a control unit for controlling an operation of the transceiver cell. The transceiver cell includes: a substrate; at least one membrane suspending from the substrate; and a plurality of transducer elements mounted on the at least one membrane. Each of the plurality of transducer elements has a bottom electrode, a piezoelectric layer on bottom electrode, and at least one top electrode on the piezoelectric layer. Each of the plurality of transducer element generates a bending moment in response to applying an electrical potential across the bottom electrode and the at least one top electrode and develops an electrical charge in response to a bending moment due to the external pressure wave.

A hybrid piezoelectric energy harvesting transducer system includes: (a) first and second symmetric, pre-curved piezoelectric elements mounted separately on a frame so that their concave major surfaces are positioned opposite to each other; and (b) a linear piezoelectric element mounted separately on the frame and positioned between the pre-curved piezoelectric elements. The pre-curved piezoelectric elements and the linear piezoelectric element are spaced from one another and communicate with energy harvesting circuitry having contact points on the frame. The hybrid piezoelectric energy harvesting transducer system has a higher electromechanical energy conversion efficiency than any known piezoelectric transducer.

The present method makes use of a second receiver-transmitter pair, which, together with a first pair, forms a quadrilateral figure, the horizontal sides of which are parallel to the level of a liquid. In addition, the values of the energy characteristics of Lamb waves propagated simultaneously both between each of the horizontal receiver-transmitter pairs and between a second vertical receiver-transmitter pair are calculated using values obtained from certain horizontal pairs to determine the initial and final values of the measuring scale of other pairs, by means of which the height of the liquid level is determined and / or measured. The device comprises an acoustic receiver and an emitter, each provided with a piezoelectric transducer, which are mounted at a set distance from one another such that a liquid level monitoring region lies therebetween for the simultaneous excitation of a symmetrical and an antisymmetric normal zero mode Lame wave, the device further comprising a second acoustic receiver-transmitter pair and a signal generating and converting unit. Technical result: increased monitoring accuracy together with increased monitoring speed and a broader scope of application.

The invention discloses a micro-electromechanical system piezoelectric transducer and a manufacturing method thereof, in particular an array piezoelectric transducer and a manufacturing method, and belongs to the micro-electromechanical system field. The transducer adopts array design and is composed of at least two array elements. The wafer-level electrical series connection or parallel connection between the array elements is realized by a micro-electromechanical system (MEMS) process compatible with the semiconductor process, but at least one electrical series connection is provided; Semiconductor MEMS process can effectively control the parasitic capacitance generated by electrical series and parallel connection, thus effectively improve the sensitivity. The invention improves the sensitivity of the transducer through the wafer-level electric series and parallel connection between the array elements. Compared with the traditional piezoelectric ceramic transducer, the parasitic capacitance caused by the following circuit string and parallel connection is avoided. A wafer-level array MEMS transducer is proposed. The array transducer can be connected in series with different arrayelements according to the needs, so that the sensitivity of the transducer can be defined independently. The transducer also has the advantages of high signal-to-noise ratio, low cost, low electricalnoise and high signal-to-noise ratio.

An acoustic sensor for use in a downhole measurement tool is provided. The acoustic sensor includes a piezoelectric transducer and a backing layer having at least one powder material disposed in an elastomeric matrix material. In various exemplary embodiments, the backing layer includes first and second tungsten powders disposed in a fluoroelastomer matrix material. Exemplary embodiments of this invention may advantageously withstand the extreme temperatures, pressures, and mechanical shocks frequent in downhole environments and thus may exhibit improved reliability. A method for fabricating an acoustic sensor is also provided.

A noise reduction system for use with an exhaust nozzle associated with a jet engine of an aircraft. The noise reduction system employs a plurality of flow-altering components disposed circumferentially about a lip portion of an exhaust nozzle. In one preferred form the flow-altering components each comprise piezoelectric transduction layers. The flow-altering components are caused to move in an oscillating manner by an AC signal applied thereto such that they move into and out of the exhaust gas emitted from the exhaust nozzle to achieve a desired degree of intermixing of the exhaust flow with the flow adjacent the exhaust nozzle. This produces a reduction in the noise generated by the jet engine. The noise reduction can be utilized during takeoff conditions of an aircraft. The flow-altering components are maintained out of the exhaust gas flowpath during cruise conditions of the aircraft so as not to cause a reduction of thrust, that would in turn result in an increase in the fuel burn during cruise conditions.

The invention discloses a manganese-doped niobium nickel-lead zirconate titanate piezoelectric ceramic material and a preparation method thereof. The composition of the piezoelectric ceramic material is Pb[(Ni1 / 3Nb2 / 3)x(ZryTi1-y)1-x]O3+zM, wherein in the formula, x, y and z represent the molar content; M is manganese or oxide of manganese; and x is more than 0.0 and less than 0.9, y is more than 0.0 and less than 0.8, and z is more than 0.0 and less than 0.3. The novel piezoelectric ceramic material with excellent comprehensive performance is obtained by preserving heat and sintering for 0.5 to 10h at the temperature of 1,000 to 1,300 DEG C by the traditional solid-phase sintering process; and the piezoelectric ceramic material has a relatively high mechanical quality factor (Qm-670), a good ferroelectric property (Ec-4.3kV / cm) and a good piezoelectric property (d33-495pC / N). The novel piezoelectric ceramic material is mainly applied to devices such as micro-actuators, piezoelectric transducers, surface wave filters and piezoelectric sensors.

The invention relates to a magnet-free bistable piezoelectric transducer which comprises a piezoelectric transduction unit, a fixture and a transmission unit. The piezoelectric transduction unit is made of piezoelectric materials; the piezoelectric transduction unit is clamped by the fixture, the fixture provides axial compressive force to the piezoelectric transduction unit, and the axial size of the piezoelectric transduction unit is larger than the distance between two clamp arms of the fixture; the transmission unit is used for outputting electric energy generated when the piezoelectric transduction unit deforms, and electric energy from an external power source can be inputted into the piezoelectric transduction unit by the transmission unit. The magnet-free bistable piezoelectric transducer has the advantages that the magnet-free bistable piezoelectric transducer not only can be used for collecting vibration energy, but also can be used as a driver to realize electric driving and on-off control functions.

The invention discloses a traffic load pavement vibration energy piezoelectric power generation measuring method and a system thereof. The traffic load pavement vibration energy piezoelectric power generation measuring system comprises a piezoelectric transduction unit, a total control module and a total measuring module which are arranged on a pavement. The piezoelectric transduction unit is used for converting pavement vibration energy into electric energy. The total control module is used for regulating speed and applying load for running vehicles and regulating electric parameters for output electric power. The total measuring module is used for measuring speed and load of a vehicle, stress and deformation of the pavement, harvested alternating-current and voltage, and transduced voltage and current. The generated electric energy can be used as a power supply to be stored and utilized. According to above condition, the traffic load pavement vibration energy piezoelectric power generation measuring system provides conditions for researching a mechanism of a pavement piezoelectric energy harvesting technology, application and popularization of the technology, and has a high academic value and social value.

The invention discloses detection device and method for a service bridge inhaul cable / suspension cable anchor system. The device comprises a detection circuit which is mainly formed by an ultrasonic generation and excitation part, a piezoelectric transducer (6) and a signal collector (7), and a detection mechanism which is mainly formed by a first clamp for fixing an inhaul cable / suspension cable of an anchor system, a second clamp for connecting a transmitting probe and the piezoelectric transducer with the anchor system through a coupling agent (2), and a PC machine. The method comprises the steps as follows: a transmitter obtains working voltage from alternating current through an adjustable transformer and a direct-current rectifier module; the transmitting probe generates an ultrasonic wave under excitation of the voltage, and is introduced into the inhaul cable / suspension cable in an anchor area through the coupling agent; the piezoelectric transducer transforms an ultrasonic wave reflected by the anchor area into a corresponding electric signal; the electric signal is processed and analyzed in the PC machine, so as to obtain defect information of the anchor system. The detection device and method have the advantages of being good in stability, high in detection sensitivity, low in cost, convenient to use and the like.

The invention discloses a supermarket payment system based on an NFC technique and a payment method thereof. The system is composed of an NFC payment unit, an RFID reading unit, a liquid crystal display screen, an infrared detection unit, a keyboard unit and a payment control unit. A whole payment zone is divided into a waiting zone and a payment zone. The waiting zone and the payment zone are separated from each other by a first gate inhibition. The boundary of the payment zone is defined by the first gate inhibition and a second gate inhibition. The RFID is composes of three RFID readers which are in parallel arrangement in the payment zone. The first two RFID readers are activated by an infrared sensor in the waiting zone. When the second reader has new data, the third reader is activated, and an electronic label is further read. Could computing enables various data to be stored in a cloud, so that largest sharing of the data can be realized. The structure of RFID three-parallel arrangement enables the reading of the electronic label to be more comprehensive and accurate. In addition, piezoelectric transduction equipment enables electric energy to be saved, and outage emergency response capability is improved.

Provided are: a piezoelectric oscillation piece which has a pair of oscillation arms disposed in parallel with each other with base ends of the oscillation arms fixed to a base of the piezoelectric oscillation piece and with weight metal films formed at the tips of the oscillation arms; a base substrate on the upper surface of which the piezoelectric oscillation piece is mounted; a lid substrate joined with the base substrate such that the mounted piezoelectric oscillation piece can be accommodated in a cavity; and a control film disposed in the vicinity of the pair of the oscillation arms as viewed in the plan view and formed at least on either of the substrates in such a manner as to extend from the base end side to the tip side in the longitudinal direction of the oscillation arms for increasing the degree of vacuum inside the cavity by heating. The control film is locally deposited on the side surfaces of the oscillation arms in the vicinity of the control film by heating.

The invention relates to a circular membrane piezoelectric ultrasonic transducer, which aims to provide a vibration piezoelectric ultrasonic transducer with high transduction efficiency in order to overcome the shortcoming that the conventional ultrasonic transducer is low in transduction efficiency. The circular membrane piezoelectric ultrasonic transducer comprises a siliconchip, a supporting layer positioned on the siliconchip, and two piezoelectric transduction units positioned on the supporting layer, and is structurally characterized in that: the external piezoelectric unit encircles the internal piezoelectric unit; and the two units provides alternating-current excitation of which the constant phase difference is Pi, so the working efficiency of the transducer is improved. The specific sizes of the two units can be optimally regulated according to a design requirement of the transducer.

A mass energy conversion device adopting gas energy storage and double-cylinder reciprocation vibrating piezoelectric transduction and applied to railway remote monitoring comprises a box, travel transforming mechanisms, pressure energy storage mechanisms, a high-pressure gas storage cavity and a pneumatic power generation mechanism. The device can convert vibration kinetic energy during train operation into electric energy and provide energy for railway remote monitoring equipment, and long-term stable remote monitoring for safe operation of the railway can be realized in an environment without power and a power supply.

A stringed musical instrument having an enhanced musical sound, the instrument including one or more capture devices, e.g., a piezo-electric transducer, communicable with at least one structural portion of the musical instrument. The capture devices are configured to detect vibration and convert the vibration to an electrical signal that is transmitted to an amplification device. The amplification device is configured to allow a user to modify the electrical signal for transmission to an external device such as an amplifier and speaker system.