Abstract: An in-situ apparatus is provided for monitoring the state of stress/strain and cracking in a die surface. The apparatus may also be used to facilitate the prudent removal of the die from the surface so that it may be repaired before catastrophic failure occurs. Accordingly, the yield of a process used to generate die cast structures may be greatly increased.

Abstract: A tire assembly with integrated power generation features includes one or more piezoelectric devices configured to generate electric charge therein upon being subjected to mechanical strains associated with flexure of tire or wheel components. The piezoelectric device may be incorporated in a variety of tire structures and in many different locations. In pneumatic tire structures, the piezoelectric device and related electronics may be embedded in crown or sidewall locations among such selected components as the exterior tread portion, first and second steel belts of a belt package, carcass, cap ply portion, inner liner, zone base, etc. The piezoelectric device with optional rubber casing may also be attached to such locations as the inner liner and tire exterior. Piezoelectric devices may also be integrated with a tire and safety support combination that is configured to operate in an extended mobility mode when the tire structure loses air pressure.

Abstract: A stress sensitive element includes a vibrating arm having an electrode, a beam portion integrated with the vibrating arm at both ends of the vibration arm, and a connecting portion interposed between the beam portion and the vibrating arm. The element is placed by providing a fixing portion to one of the connecting portion and the beam portion, and an extending direction of the vibrating arm is orthogonal to a stress direction to be detected.

Abstract: A transducer housing for an ultrasonic fluid meter. At least some of the illustrative embodiments a transducer housing comprising a housing having a proximal end, a distal end and an internal volume, the housing couples to a spoolpiece of an ultrasonic meter, and an acoustic matching layer that fluidly seals the distal end from the internal volume (wherein the housing accepts a piezoelectric element within the internal volume and proximate to the acoustic matching layer). The acoustic matching layer has an acoustic impedance between that of the piezoelectric element and a fluid within the ultrasonic meter.

Abstract: The present invention is directed to sensors that use wide band gap piezoelectric films such as aluminum nitride and zinc oxide. The films can be deposited with chemical and physical methods and etched or micro machined into miniature and micro sensing elements. Various piezoelectric sensing structures such as compression mode and cantilever-type accelerometers, diaphragm-type pressure sensors, and micro sensor arrays can be manufactured with the sensing elements. They can be used in the measurements of vibration, shock, dynamic pressure, stress, and high resolution ultrasound non-destructive test at high temperature up to 800-1000° C.

Abstract: The invention relates to a piezoelectric pressure sensor comprising an outer housing separated by an annular gap from an inner housing, which inner housing is attached to the outer housing on the pressure side. At least one piezoelectric measuring element being positioned between a diaphragm placed on the pressure side of the inner housing and a base part of said inner housing. The inner housing is provided with a massive cylindrical wall throughout, whose wall thickness essentially corresponds to the thickness of the adjacent outer housing, and in the annular gap between outer housing and inner housing or in the space between the base part of the inner housing and an interior shoulder of the pressure sensor there are provided means for transferring heat to the outer housing.

Abstract: Sensors that include SAW devices, related methods, and related devices. Many embodiments are included. Some of the present sensors include an inlet structure; a mounting structure that is spaced apart from the inlet structure, the mounting structure having a top surface and an opposing bottom surface; and surface acoustic wave (SAW) devices disposed on the top surface of the mounting structure; where (a) the mounting structure includes openings that extend from the top surface to the bottom surface through which fluid can flow that has first passed over the SAW devices during operation of the sensor, or (b) the mounting structure and SAW devices together define openings through which fluid can flow that has first passed over the SAW devices during operation of the sensor.

Abstract: A multifunction sensor system for an electrical machine includes a piezoelectric vibration sensor a resistive temperature and partial discharge sensor which may optionally be integral with the piezoelectric vibration sensor; and packaging enclosing the vibration, the resistive temperature, and the partial discharge sensors.

Abstract: A micro manipulator for electrode movement, a driving method thereof, and a brain signal measuring device using the same are provided.

Abstract: A piezoelectric sensor, preferably a pressure sensor, comprising at least two piezoelectric measuring elements placed in a housing, which are clamped between a membrane on the pressured side of the housing and a pick-up electrode electrically insulated against the housing. The piezoelectric measuring elements are fixedly attached to the pick-up electrode by thermo-compression or soldering and together with said pick-up electrode form a compact measuring element stack, which will significantly simplify assembly of the piezoelectric sensor.

Abstract: A system that facilitates damping of mechanical vibration associated with machinery that is subject to such mechanical vibration. The system comprises machinery with at least one moveable part and a piezoelectric actuator that is selectively applied to the machinery. The piezoelectric actuator receives voltages and is employed to facilitate damping of mechanical vibration associated with the machinery.

Abstract: An inertial drive actuator includes a vibrating substrate configured to be reciprocally moved by small reciprocally displacements generated by a displacement generating unit arranged on a fixing member. The vibrating substrate has a first electrode on a plane of the vibrating substrate and an insulating layer on the first electrode. The inertial drive actuator further includes a mobile object arranged on the plane of the vibrating substrate and having a second electrode on a plane facing the first electrode through the insulating layer, a frictional force control unit configured to control frictional force between the vibrating substrate and the mobile object such that a potential difference is applied across the first electrode and the second electrode to cause electrostatic adsorptive force to act, and a frictional force applying unit configured to frictionally couple the mobile object and the vibrating substrate to each other by magnetic adsorptive force.

Abstract: A knock sensor includes: a base including an annular flange portion and a cylindrical portion, an annular piezoelectric element fitted onto the cylindrical portion, electrode portions oppositely formed on front and rear surfaces of the annular piezoelectric element, first and second terminal plates in contact with the electrode portions, an annular weight, a first insulating sheet interposed between the first terminal plate and the flange portion, a second insulating sheet interposed between the second terminal plate and the weight. The electrode portions include annular partial electrodes each having a width narrower than a radial width of the piezoelectric element. The annular partial electrode has a thickness d satisfying: L/d<80 where L is a radial dimension of outer circumferences of the front and rear surfaces where the electrode portions are not arranged.

Abstract: A method is provided for manufacturing an actuator device including a substrate, a vibration plate, lower electrode, and a piezoelectric element having a piezoelectric layer, and an upper electrode. The vibration plate is formed by forming an insulating film comprised of a columnar crystalline zirconium layer whose surface has an average crystal grain size of about 20 to 50 nm on one surface the substrate, and then thermally oxidizing the zirconium layer into a columnar crystalline zirconium oxide layer whose surface has an average crystal grain size of about 20 to 50 nm. The zirconium layer shows an XRD pattern having a (002) plane peak with an FWHM of 0.4 or less. The piezoelectric element is formed on the lower electrode.

Abstract: A device and method for the detection of the interaction between two or more objects is disclosed. The device utilizes electrical impedance spectra measured from a piezoelectric element attached to one such object. Comparison of such spectra along a range of traverse allows precise estimates of distance to be made. One useful application is the topographical mapping of a surface.

Abstract: A transducer including a transducer body, a sensor associated with the transducer body, an electrical connector assembly fastened to an end of the transducer body, and a vibration damper system disposed between the end of the transducer body and the electrical connector assembly. The vibration damper system being operative for attenuating vibrational acceleration and amplification forces experienced by the electrical connector assembly when the transducer is exposed to vibration.

Abstract: An o-ring sealing device, molded with an imbedded piezoelectric element, for use in vacuum systems. The imbedded element, of a circumferential length, has an oblong cross-sectional shape, the oblong shape having a pair of ends for externally connecting to a signal processor. The piezoelectric element is concentrically disposed and centrally placed within a mold cavity of a predetermined diameter. The cavity is filled with an elastic material fully encapsulating and insulating the piezoelectric element.

Abstract: A multifunction sensor based on a bulk acoustic wave (BAW) device can be used to obtain measurements of a liquid's corrosivity, viscosity, and conductance. A front electrode and a back electrode can be used to excite vibrations in a piezoelectric substrate. Vibrations in the piezoelectric substrate cause an electrical signal that can be measured as a voltage differential between the front and back electrodes. The signal amplitude is an indication of the liquid's viscosity. The signal frequency is an indication of corrosivity because corrosion can change the sensor's fundamental frequency over time. A third electrode, a runner, can be placed near the front electrode. A voltage difference between the runner and the front electrode can cause a current to flow between them and through the liquid. The voltage difference and the current indicate the liquid's conductivity.

Abstract: A system that facilitates damping of mechanical vibration associated with machinery that is subject to such mechanical vibration. The system comprises machinery with at least one moveable part and a piezoelectric actuator that is selectively applied to the machinery. The piezoelectric actuator receives voltages and is employed to facilitate damping of mechanical vibration associated with the machinery.

Abstract: A signal generation system, comprising a piezoelectric device which, upon actuation, generates voltage, and a wireless transmitter which generates a wireless signal when the piezoelectric device generates the voltage. A signal generation system, comprising signal generating devices, each wireless transmitter generating a respective signal comprising transmission which identifies the wireless transmitter. A signal generation system, comprising signal generating devices, each of the signal generating devices being mounted in or on respective structures which are free to move any distance relative to each other. A method of generating a signal, comprising actuating a piezoelectric device to generate an electrical signal, conveying the signal to a wireless transmitter, and transmitting a wireless transmission.

Abstract: A piezoelectric device having a piezoelectric film and methods of making such. The piezoelectric device can be used in circuits to dampen or dissipate vibrations in equipment such as racquets, and ski apparatus.

Abstract: An acoustic wave sensor having a piezoelectric substrate shaped to generate lateral electric fields. The sensor has a pair of electrodes deposited upon a reference surface of the substrate. A sensing surface that is opposite from the reference surface is adapted to be immersed in an environment, such as a gas or a liquid.

Abstract: The invention relates to a method for the manufacture of piezoelectric multilayer actuator in which thin layers of a piezoceramic material, called “green leaves” on which at least one internal electrode is applied, are stacked to form a block such that the internal electrodes are guided in alternation to oppositely lying surfaces of the actuator, where they become bound together by an external electrode, the actuator compact being sintered and subjected to abrasive shaping, and then the base metallization is applied for the external electrode.

Abstract: An improved human motion applicator assures a quick and sufficient amount of displacement given to a part of a human body. The applicator includes a support adapted to be fitted on the part of the human body. The support carries at least one electro-active elastic actuator in a force-transmitting relation to the human part. The actuator includes a dielectric core and a pair of electrodes on opposite of the core for receiving a driving DC voltage thereacross. The elastic actuator has a length and elastically deforms in the lengthwise direction to exert a stretching force to the human part to a greater extent as the driving DC voltage increase. The applicator also includes a controller which applies the driving DC voltage of varying levels to the elastic actuator, thereby generating a varying motion-inducing force to be applied to the part of the human body.

Abstract: A system for generating electrical energy in a tire for a vehicle includes at least one piezoelectric element that generates electrical energy when deformed. The at least one piezoelectric element is associated with the tire and is elongate. The at least one piezoelectric element extends along at least a portion of the tire and is electrically connected to an electrical circuit. The electrical circuit is not in electrical communication with the vehicle. The tire is mounted on a rim of the vehicle. An associated tire is also disclosed.

Abstract: A very compact interference frequency generator (11) which emits with an extremely wide band width and extremely powerfully is afforded by the combination of a mechanical pulse generator (25) with two piezoelectric pillars (13) which are disposed axially in succession and which can be axially acted upon by the pulse generator (25) and which are electrically connected in series in opposite relationship and which are electrically conductively connected with their mutually remote ends (18) to electrodes (34) which extend parallel to the piezoelectric pillars (13) to an electrically conductive coupling portion (15) between the piezoelectric pillars (13) where they end as electrodes (36) of an axial spark gap and at the same time spark gaps (37) which are oriented inclinedly radially towards the coupling portion (15).

Abstract: An apparatus for measuring pressure includes a cylindrical tube having an open end and a closed end; a piston disposed in the cylindrical tube at the open end; an accelerometer attached to a side of the piston that faces the closed end of the tube, the accelerometer for measuring the acceleration of the piston after a blast event; and a pressure sensor located inside the tube for measuring pressure in the tube between the piston and the closed end of the tube. The apparatus also includes a data processor and computer connected by wires to the accelerometer and pressure sensor for receiving signals generated by the accelerometer and pressure sensor.

Abstract: A vibration transducer specially configured for attachment to a subject's nose for producing an electrical output signal relating to a subject's snoring pattern. The transducer is shaped so as to have a rectangular portion for bridging the dorsum at least one polygonal pad area adapted to be adhesively secured to the ala nasi. The transducer is a laminated arrangement incorporating a polyvinylidene fluoride film exhibiting piezoelectric properties.

Abstract: A method for quickly screening piezoelectric transformer apparatuses having low mechanical strength and latent defects is performed by connecting a load impedance to a generator of a piezoelectric transformer apparatus and applying a stress signal to an actuator to vibrate the piezoelectric transformer apparatus. Latent-defect transformer apparatuses having low mechanical strength are damaged during this process and therefore can be easily identified.

Abstract: A piezoelectric device is assembled from a piezofilm sensor enclosed between two layers of a multilayer board with a printed circuit.

Abstract: An object detecting device can prevent a seizure of an object between an opening and an opening-closing unit for opening and closing the opening. The object detecting device includes a pressure-sensitive sensor disposed at one of the opening and the opening-closing unit, and judging means for judging the contact of the object with the pressure-sensitive sensor on the basis of an output signal of the pressure-sensitive sensor. The pressure-sensitive sensor includes pressure-sensitive means for generating an output signal depending on deformation, and support means for supporting the pressure-sensitive means at the one of the opening and the opening-closing unit, the support means including a vibration damping portion for damping vibration propagated to the pressure-sensitive means.

Abstract: A plurality of quartz crystal resonators having different resonance frequencies are connected in parallel. A combined admittance of the resonators is measured. Equivalent circuit constants of all the resonators are obtained by a method of least squares from admittance characteristics. A change in the resonance frequency is measured and mass of a substance adsorbed to a piezoelectric transducer is calculated.

Abstract: A high-frequency oscillation circuit incorporates a crystal resonator having a natural oscillation frequency in a high-frequency area within a closed circuit including one or more logic elements. Therefore, this circuit copes with an oscillation frequency of 1 MHz to 2 GHz or more in basic oscillation frequency of a crystal resonator and it oscillates with stability at the basic oscillation frequency of the crystal resonator.

Abstract: Various piezoelectric transducers are provided. In one form, a polymer film or thin ceramic piezoelectric transducer is formed of various piezoelectric (active) and dielectric (inactive) layers in which the piezoelectric effect may be attenuated locally at any given point on the surface of the transducer, by use of printed circuit patterns, preferably made by photolithography. This provides a practical realization of a distributed piezoelectric transducer with a bi-dimensional polarization profile that varies smoothly over the surface of the piezoelectric structure. Flexibility of the fabrication procedure provides a way to optimize the design of a distributed piezoelectric transducer for applications such as active vibration control. In another form, a segmented piezoelectric transducer includes a set of active elements such as piezofilms, electronics and flexible printed circuits and connected with external electronic circuitry.

Abstract: A method for producing a structural unit with a prestressed piezoelectric actuator includes the steps of inserting a front end of the actuator into a hollow body, form-lockingly or force-lockingly connecting the inserted front end of the actuator to the hollow body, pressing the actuator into the hollow body with a defined force establishing a prestress of the actuator, and force-lockingly or form-lockingly connecting the actuator to the hollow body in the vicinity of a rear end of the actuator, for fixing the prestress of the actuator.

Abstract: This present invention provides an array formed by a continous line array of piezoelectric film with discrete points of increased sensitivity to sense and measure acoustic signals. The configuration provided by the present invention simultaneously provides the advantages and attributes of both the continuous line array and the multi-element discrete array. The line array and the multi-element array are designed to enhance or cancel specific frequency bands of signal noise and to enhance beam forming of the array. The piezoelectric array can be extended and shaped into two-dimensional and three-dimensional hydrophone arrays. The present invention comprises a continuous line array formed by a single piece of piezoelectric film with one or more points of enhanced sensitivity to alter the beam pattern or spectral sensitivity of the array. The electrical output of the entire array may be observed with one set of connectors, one positive and one negative lead.

Abstract: An oscillating element, particularly for a level sensor, comprises an oscillating diaphragm (3), a stack of piezoelectric elements (6, 7), and a tie bolt (4) connected to the diaphragm (3) for pressing the piezoelectric elements (6, 7) against the diaphragm (3). The tie bolt (4) forms a single piece with the diaphragm (3).

Abstract: In an ultrasonic sensor, including a housing having a plug connector, an ultrasonic converter, and a circuit board, the housing is divided into a support and a hood enclosing the support. The support carries the circuit board, the plug connector, and the ultrasonic converter.

Abstract: A transducer assembly for use with a remotely located PC device for determining holding forces of a fastener, the fastener including a head and a shaft extending through first and second layers of material. A tightening nut rotatably secures to an extending end of the shaft. The transducer assembly includes a substantially disk-shaped printed circuit board incorporating at least one circuit configuration for communicating first and second faces of the circuit board. An input line, typically a wire harness, extends from the remote PC and is engageable, at a first location, to the first face of the circuit board. A bolt identification component, incorporating either a resistor or ID chip in a suitable circuit, is engageable at a second location to the first face of the circuit board and is communicable, via the input line, with the PC device to communicate a signal representative of the identity of the bolt to be analyzed.

Abstract: A sensor device includes a base body 12 having a vibrating portion 14, a piezoelectric element 20 fixed onto one surface of the vibrating portion 14 and having a piezoelectric film 22 and a pair of electrodes 24a, 24b which are in contact with the piezoelectric film 22, a space 16 that allows a fluid to lead to the other surface of the vibrating portion 14, and introduction holes 18 that communicate with the space 16, and the sensor device 10 is in a longitudinal shape. A recess 15 which contains at least an opening end of the introduction hole 18 on the surface side of the sensor device 10 in its region and extends up to the rear end portion 10′ of the sensor device is formed on the surface of the sensor device 10 by a protrusion 13 disposed on the surface of said sensor device so as to extend substantially continuously from the periphery of the introduction holes 18 to the rear end portion 10′ of said sensor device.

Abstract: A pressure- and temperature-sensitive transducer comprises a tubular housing, a resonator located within the housing and end caps closing the ends of the housing. The resonator is located in a radial plane with respect to the housing and is connected to the housing by two separate connecting regions. The housing, resonator and connecting, regions are formed from a single piece of double rotation cut quartz. The shape, dimensions and position of the connecting regions is chosen to optimize stress in an axis responsive to changes in pressure and temperature while minimizing stress in an axis responsive predominantly to pressure.

Abstract: A method of manufacturing a piezoelectric torque transducer is provided, comprising the steps of (a) forming a prepared area on a surface of a torsion member adapted to be strained by an applied torque; (b) providing a piezoelectric element having an axis of maximum strain sensitivity and disposing first and second electrodes on opposite faces of the element, respectively, and attaching an electrical lead to each electrode; (c) connecting electrical leads to the electrodes; and (d) disposing the element on the prepared area and orienting the axis of maximum strain sensitivity on the member and securing the element to the prepared area with a material selected from a group consisting of (i) adhesive material and (ii) potting material.

Abstract: An electrostrictive actuator incorporating a single crystal ferroelectric material is subjected to combined electrical and mechanical loading. Electrodes are used to generate an electric field in a ferroelectric plate. The subsequent domain switching process produces large strains that can be recovered by applying stress with a mechanical load.

Abstract: The invention relates to a piezoelectric actuator, in particular for actuating control valves or injection valves of internal combustion engines in motor vehicles, having a piezoelectric actuator body, in particular in the form of a multi-layer laminate of stacked layers of piezoelectric material and between them metal or electrically conductive layers acting as electrodes, in which the actuator body is surrounded by a module wall, and defines an intermediate chamber that is divided into an upper chamber portion and a lower chamber portion by an axially movable partition disposed transversely on the actuator head, and a selected one of the upper chamber portion or the lower chamber portion experiences a flow through it of a cooling air stream (L zu, L ab) for cooling the actuator body.

Abstract: The present invention provides a sensor that can be operated at high temperatures. The sensor comprises a first electrode, a second electrode, and an aluminum nitride film which lies between the first and second electrode. The sensor can be used to measure pressure, acceleration, or force at high temperatures.

Abstract: An ultrasonic wave transmitter/receiver is provided in which the transmission/reception range thereof in at least one direction is relatively narrow, and which has stable reverberation characteristics.

Abstract: A water vapor insensitive and corrosion resistant chemical or biochemical sensor device, including a transducer, coated with a protective coating of diamond or a diamond-like carbon, preferably by a pulsed laser deposition technique. The surface of the protective coating is coated with a chemoselective or bioselective absorption material or film.

Abstract: A sensor including a center post extending along the sensing axis of the sensor, a piezoelectric sensing element concentrically engaging the center post, and a preload element preloading the piezoelectric element radially outward to the axis. The center post includes a recess along the axis and the first preload element is in the recess and preloads the piezoelectric element radially outward. The sensor may include a mass concentrically engaging the piezoelectric element. The sensor senses acceleration, force or pressure.

Abstract: A micro-machined transducer having a structure in which an acoustic enclosure is formed on a substrate above the plane of the substrate surface is disclosed. Forming the acoustic enclosure on the substrate above the plane of the substrate surface, rather than an acoustic cavity in a surface of the substrate, provides an acoustic cavity whose size is not limited by the thickness of the substrate.

Abstract: A stylus has a piezoelectric element support part to support and fix piezoelectric elements. The piezoelectric element support part is a regular polygonal body and its cross section orthogonal to the axis of the stylus is made a regular polygon. The piezoelectric elements are mounted on each side surface of the regular polygonal body, respectively. Sums and difference signals outputted from the piezoelectric elements are produced and a touch detection signal is generated based on the produced signals.