Abstract: A vibration type actuator device, and particularly a vibration type actuator device is heated for a predetermined time at the starting of the actuator device, and is operated thereafter.

Abstract: A method and device for selectively reducing the frequency-temperature shift of piezoelectric crystals. The piezoelectric device (100) includes a substrate (102), a piezoelectric element (106) and a temperature dependent interface structure (120) for beneficially stressing the piezoelectric element at a predetermined temperature range. The substrate (102), piezoelectric element (106) and temperature-dependent interface structure (120) define a piezoelectric package having a predetermined non-compensated third order Bechmann curve having a low temperature end and a high temperature end, with an inflection point therebetween, whereby the frequency-temperature shift is reducable on the third order Bechmann curve.

Abstract: A piezoelectric vibrator includes a thin quartz plate portion for generating vibrations, and non-contact electrodes for applying an alternating electric field. The electrodes are arranged on opposing sides of the thin quartz plate portion so as to not contact with the thin quartz plate portion. The electrodes may be formed on a supporter which can be bonded directly to the thin quartz plate. The electrodes may also be formed above the thin quartz plate and supported by the plate outside the thin quartz plate portion. The piezoelectric vibrator has a superior Q of resonance at high frequencies.

Abstract: A device for improving heat dissipation inside an ultrasound probe and reducing heat build-up near the transducer face. Heat conductors are placed around the periphery of the transducer package, but within the probe housing, so that heat can be drawn away from the transducer face and toward the rear/interior of the probe. The heat conductors act as conduits for draining away heat which builds up in the thermal potting material during pulsation of the piezoelectric transducer elements. The heat conductors are formed from metal foil having a heat conductivity greater than the heat conductivity of the thermal potting material which fills the spaces inside the probe housing and surrounds the transducer package. The preferred metal foil is aluminum.

Abstract: A piezoelectric resonator (21) utilizing a width expansion mode, which is formed by coupling support parts (26, 27) to nodal points of a piezoelectric resonance part (22) utilizing a width expansion mode including a rectangular piezoelectric ceramic plate (23) and electrodes (24, 25) formed on both surfaces thereof, and coupling dynamic dampers (28, 29) on other ends of the support parts (26, 27) respectively.

Abstract: The vibrator includes, for example, a triangular prism shaped vibrating body. On each of three side faces of the vibrating body, piezoelectric elements are formed respectively. The vibrating body makes bending vibration by giving a driving signal to one or two piezoelectric elements. The vibrator is used in a vibratory gyroscope. In this case, for example, one piezoelectric element is used for vibrating the vibrator. When a rotating force is applied to the vibratory gyroscope, a Coriolis force is exerted to produce output voltages on the remaining two piezoelectric elements corresponding to the rotational angular velocity.

Abstract: A method and device for selectively reducing the frequency-temperature-shift of piezoelectric crystals. The piezoelectric device (100) includes a substrate (102), a piezoelectric element (106) and a temperature dependent interface structure (120) for beneficially stressing the piezoelectric element at a predetermined temperature range. The substrate (102), piezoelectric element (106) and temperature-dependent interface structure (120) define a piezoelectric package having a predetermined non-compensated third order Bechmann curve having a low temperature end and a high temperature end, with an inflection point therebetween, whereby the frequency-temperature shift is reducable on the third order Bechmann curve.

Abstract: A distribution network of electric signals in a piezoelectric or ultrasonic waves motor, is produced by depositing electrodes of conductive material on one face of a strip in dielectric material, that on the other face of the strip conductive tracks are deposited according to an interconnection diagram, designed beforehand to supply the piezoelectric elements with proper voltage. Drillings are made through the strip between the conductive tracks and the electrodes, and through plating or deposit of conducting material, these drillings are made conductive.

Abstract: A piezoelectric/electrostrictive element including a thin ceramic substrate, and a piezoelectric/electrostrictive portion formed on the ceramic substrate by a film forming technique without an adhesive agent, the piezoelectric/electrostrictive portion consisting essentially of a plurality of electrodes and at least one piezoelectric/electrostrictive layer. The ceramic substrate is formed of a material which includes as a major component zirconia having a crystal phase that is stabilized by addition of at least one compound selected from the group consisting of: yttrium oxide, ytterbium oxide, cerium oxide, calcium oxide and magnesium oxide.

Abstract: An electronic circuit including a frequency-selective part including a piezoelectric crystal and an inductance; The crystal is shaped relative to its crystal axes in such a way that its temperature coefficient and the temperature coefficient of the inductance have opposite signs in order to reduce the influence temperature on the pulling range of the frequency-selective part of the circuit.

Abstract: A Colpitts-type oscillation circuit, employing a ceramic resonator vibrating in the energy trapping thickness shear slide mode is disclosed in which, an antiresonance frequency of the ceramic resonator has a negative temperature characteristic which is less step than that of its resonance frequency. Capacitance between terminals of the ceramic resonator is set so that an oscillation frequency (Fosc) of the oscillation circuit at the ordinary temperature is higher than a central frequency ((Fr+Fa)/2) of the ceramic resonator. Thus, it is possible to employ a ceramic resonator having a large bandwidth (.DELTA.F), thereby improving the temperature characteristic of the oscillation frequency.

Abstract: To drive a piezoelectric element for use in a dot matrix printer for a period of time defined by .pi.LC/2, the fact that the electrostatic capacitance C of a piezoelectric element changes depending on the temperature thereof is considered. The piezoelectric element is supplied with a voltage from a D.C. power source when a switching transistor is being ON. A temperature sensor is provided which senses the temperature of the piezoelectric element. A microcomputer serving as a control circuit has a ROM in which ON durations Ton for the switching transistor are stored in relation to temperatures to be output from the temperature sensor. At the time of printing, a suitable ON duration corresponding to the sensed temperature is selected by the control circuit from the table so that the piezoelectric element is always displaced the same amount independently of the temperature of the piezoelectric element.

Abstract: A piezoelectric sensor for detecting vibrations is disclosed, the sensitivity of which is less temperature dependent than that in the prior art even when it is used in a broad temperature range. A lower member made of alumina is secured by an epoxy type adhesive to the inner bottom surface of a vessel made of an iron-nickel alloy containing 42% by weight of nickel. A piezoelectric element using a PZT piezoelectric body is secured by an adhesive to the lower member 33. An upper member made of alumina having electrodes is secured to the piezoelectric element with the electrodes of the upper member and those of the piezoelectric element soldered to one another. The plan dimensions of the upper and lower members are slightly greater than those of the piezoelectric element. On the lamination including the piezoelectric element and lower and upper members, a thermally shrinkable tube is fitted, thus forming spaces adjacent the top surface and periphery of the piezoelectric element.

Abstract: A thin-walled rigid tube made of aluminum or other strong material that is a good thermal conductor and a good transmitter of megasonic energy is provided with an external sheath of Teflon to shield the tube from fluids used in cleaning semiconductor wafers. Arcuate transducers are coupled to the interior of the tube and energized with megasonic energy to transmit energy through the tube into fluid surrounding the wafers. A partition in the tube divides the tube into two or more chambers. Nitrogen is conducted through a tube end cap and through the chamber containing the transducers. Cooling water is ducted through the other chamber to conduct heat away from the assembly.

Abstract: An ultrasonic electrostrictive transducer for transmitting and receiving ultrasonic energy and having an expanded operating temperature range, preferably about room temperature. The transducers may be made from PMN-PT solid solutions having select mole percentages of PT and being doped with La, whereby the operating temperature range about a given operating temperature may be effectively doubled.

Abstract: The features of the present invention are 1) to apply metallization on the bonding surface of a piezoelectric ceramic with a metal likely to react with the piezoelectric ceramic material, 2) when the piezoelectric ceramic material is soldered on the bonding surface, to apply metallization with a metal likely to react with the solder material, 3) to provide between the metallizing layers formed in 1) and 2) a metallizing layer including metal which prevents reaction between the metals and their diffusion, 4) to use a mounting member for the piezoelectric ceramic which has substantially the same thermal expansion coefficient as the piezoelectric ceramic in non-polarization condition and 5) to solder in the non-polarization condition and thereafter to polarize.

Abstract: A crystal resonator having reduced acceleration sensitivity in which the resonator blank having one or more electrodes thereon has stiffening cover plates mounted to its top and bottom faces and spaced from the resonator blank by sidewalls.

Abstract: A piezoelectric tuning fork resonator having a piezoelectric substrate provided with a stepped portion on its end and a tuning fork arm portion formed in the stepped portion. A dummy substrate is arranged adjacent to a side of the piezoelectric substrate and a pair of sealing substrates are pasted onto upper and lower portions of the piezoelectric substrate and the dummy substrate to form a chip type piezoelectric tuning fork resonator. In another embodiment piezoelectric substrate includes a resin sealing portion having a hollow portion defined around the tuning fork arm portion so as to form a resin-coated piezoelectric tuning fork resonator.

Abstract: A flow rate control valve including a valve chest having an open end, an inflow passage and outflow passage each having one end communicating with the valve chest and the other end opened, a valve seat provided at the end of the inflow passage or outflow passage communicating with the valve chest, a sheet-like diaphragm provided to tightly close the open end of the valve chest and a stacked-type dispalcement device made of an electromechanical transducing material exhibiting the maximum value of piezoelectric distortion constant at a higher temperature range than 100.degree. C. or above and which exerts a pressure on the diaphragm by its deformation to change the position of the diaphragm, thereby controlling the gap between the valve seat and the diaphragm.

Abstract: A thin quartz plate having opposite major surfaces, each of the opposite major surfaces having a geometrical shape symmetrical or antisymmetrical with respect to an axis of reference; and X, Y and Z crystallographic directions corresponding to electrical, mechanical and optical axes, respectively, of the quartz plate, wherein the axis of reference forms an angle .psi. with said X axis, and the major surfaces form an angle .theta. with a plane defined by said X and Y axes, the angles .theta. and .psi. being chosen such that the first order frequency-temperature coefficient (.alpha.) of the quartz resonator is substantially 0, and the second order frequency-temperature coefficient (.beta.) of said quartz resonator is substantially 0. The shape of the resonator may be rectangular, square, polygonal, circular or elliptical. The resonator is fixed on a supporting base by means of at least one pair of connecting arms located on the extension of a nodal line.

Abstract: A piezoelectric effect device has a piezoelectric body comprised of a sintered multilayer pillar composed of alternately laminated piezoelectric ceramic sheets and internal electrodes such that edges of the internal electrodes are alternately insulated every one another layers along opposite side faces of the sintered multilayer pillar, and a pair of external electrodes provided on the opposite side faces to electrically connect to noninsulated edges of the internal electrodes. There is provided a metal stem having a pair of hermetically sealed external terminals electrically coupled to the pair of external electrodes. A metal case having flexibility in a displacement direction of the piezoelectric body is seal-welded to the metal stem at their contacts to hermetically enclose the piezoelectric body. A pair of metal pads having a linear thermal expansion coefficient less than ten times as that of the piezoelectric body are provided to substantially cover opposite end faces of the piezoelectric body.

Abstract: An electronic switch is disclosed using a piezoelectric push button transducer and an electronic switching circuit. The push button piezoelectric transducer is connected with the switching circuit with a polarity to provide a switching voltage in response to actuation of the push button switch by finger pressure. The connection is such that the polarity of the voltage generated as a result of differential thermal expansion of the piezoelectric transducer is opposite that produced by finger pressure on the push button switch and does not produce false switching from fast temperature rise. In order to protect against false switching due to high temperature soak of the electronic switch, a thermistor is provided in the electronic switching circuit.

Abstract: A solid state motor includes a plurality of piezoelectric elements assembled in a stack. Each element has two opposing planar surfaces. A plurality of electrodes each has a planar section contacting the planar surfaces of two adjacent elements in the stack. A silicone adhesive is adapted to adhere to the piezoelectric elements A plurality of alumina particles are disposed in the silicone adhesive A protective housing cylindrically encases the combination of the stack, electrodes, and silicone adhesive.

Abstract: A driving piezoelectric bimorph element for tuning fork vibration and a detecting piezoelectric bimorph element for angular rate detection are aligned and put together, end to end, with their vibration directions positioned perpendicular to each other.Two of the above structure are made into a tuning fork like angular rate sensor. The polarization directions of the piezoelectric elements, that make up the piezoelectric bimorph element by bonding them together are made the same and also the two outer electrodes of the bimorph element are connected electrically with each other, with a resultant angular rate sensor capable of detecting angular rates in a stable manner against changing ambient temperatures. Particularly, the use of a conductive film electrode for making a connection between two outer electrodes and the almost equal surface areas between two outer electrodes made it possible for the angular rate sensor to detect angular rates with much stability and less temperature drifts.

Abstract: A piezoelectric/electrostrictive actuator including a ceramic substrate (2, 10, 16, 22, 38) and a piezoelectric/electrostrictive portion (26, 28, 29, 30, 33a, 33b, 36a, 36b, 37, 39). The ceramic substrate has at least one recess (6, 14, 20, 24, 42) having a bottom surface which defines a thin-walled portion (8a, 22a), and the piezoelectric/electrostrictive portion is formed on the thin-walled portion of the ceramic substrate.

Abstract: A micro-machined resonator, typically quartz, with upper and lower micro-machinable support members, or covers, having etched wells which may be lined with conductive electrode material, between the support members is a quartz resonator having an energy trapping quartz mesa capacitively coupled to the electrode through a diaphragm; the quartz resonator is supported by either micro-machined cantilever springs or by thin layers extending over the surfaces of the support. If the diaphragm is rigid, clock applications are available, and if the diaphragm is resilient, then transducer applications can be achieved. Either the thin support layers or the conductive electrode material can be integral with the diaphragm. In any event, the covers are bonded to form a hermetic seal and the interior volume may be filled with a gas or may be evacuated. In addition, one or both of the covers may include oscillator and interface circuitry for the resonator.

Abstract: In a piezoelectric resonator having an ultrathin vibratory portion formed by a cavity made in a piezoelectric block and a thick frame-like rib formed integrally with said vibratory portion and surrounding it, an excess adhesive receiving groove or the like is cut in one marginal portion of the frame-like rib between an adhesive coated region. The resonator is fixedly housed in a package by use of an adhesive coated on one marginal portion of the frame-like rib along the z-axis direction, or by means of elastic pawls without using the adhesive. In this case, one marginal portion of the frame-like rib on the opposite side from a pad deposited on one side of the piezoelectric resonator is bonded to the bottom of the package.

Abstract: Heat-generating ovenized crystal oscillators can be directly mounted to a circuit board. Thermal isolation of an OCO from heat-sinking circuit board material and other temperature-sensitive components on a circuit board is accomplished by means of perforations (12) in the circuit board that surround the mounting area of the OCO on the board.

Abstract: A resonator has a parallelepipedal bar of a piezoelectric material designed to vibrate in an extension mode, and suspension means of said bar which form a single, integral part with the latter and which are only connected to one of its lateral faces. This arrangement makes it possible to reduce the number of parasitic vibration modes which could couple to the main mode as well as coupling between these modes, and hence variations as a function of the temperature in the characteristics of the resonator, notably in its quality factor.

Abstract: A path length control driver apparatus includes a base plate having a first central member having first and second opposite ends, a first outer rim membr and a first flexible annular diaphragm area having first and second opposite sides. The first flexible annular diaphragm area is between and integral with the first central member and the first outer rim member. A central axis passes centrally through the first and second opposite ends of the first central member. A first piezoelectric ceramic material has first and second opposing sides and the first side of the first piezoelectric ceramic material is rigidly affixed to the first flexible annular diaphragm area's first side. A second piezoelectric ceramic material has first and second opposing sides and the first side of the second piezolectric ceramic material is rigidly affixed to the first flexible annular diaphragm area's second side.

Abstract: This invention relates to an acceleration sensor having less output drift due to temperature change and noise due to external induction which includes a piezoelectric device formed of a piezoelectric member having one or more electrodes provided on each of sides thereof and a lining member of low linear expansion coefficient adhered to one side thereof. A low linear expansion coefficient circuit substrate is provided having the piezoelectric device adhered to one side thereof and having a signal processing electronic circuit formed on the other side thereof. A cabinet having three layers, including an internal conductive resin layer, an adiabatic resin layer, and an external conductive metal layer, completely enclose the piezoelectric device and the circuit substrate.

Abstract: A laminar longitudinal-effect type piezoelectric or electrostrictive driver which is displaced upon application of an electric field thereto. The driver includes laminar electro-mechanical converting elements each undergoes a displacement in a direction of the electric field due to the longitudinal mode of the reverse piezoelectric effect or the electrostrictive effect, and the temperature compensating elements each of which is interposed between the appropriate adjacent two laminar electro-mechanical converting elements. The temperature compensating elements have a higher coefficient of linear thermal expansion in the direction of the electric field or direction of displacement of the driver. The driver is suitably usable for an actuator for operating a print element of a printer, for example.

Abstract: A hermetically sealed electrostrictive actuator comprises a metal case and a metal cap for housing an electrostrictive element therein. The metal cap is provided with a pair of glass sealing terminals to be connected to a pair of lead wires of the electrostrictive element. The metal case is provided a flexible region so as to follow the expansion and constraction of the electrostrictive element without breaking the hermetic envelope of the metal case and the metal cap.

Abstract: A low-cost SAW device package comprises a ceramic or glass carrier chip, a SAW device substrate mounted on the carrier chip via a conventional adhesive and a package cover mounted over the SAW device by a glass frit. The glass frit provides a tight vacuum seal for the SAW device so that outside contamination is prevented. The package cover is fabricated of a low-cost nonmetallic, non-single crystalline material (i.e. glass) having thermal characteristics similar to or the same as those of the SAW device substrate. The packaged SAW device is mounted into a circuit or subsystem using conventional bonding techniques.

Abstract: An actuator driven by a piezo-electric element in this invention is provided with a piezo-electric element whose negative linear expansion caused by the change of circumjacent temperature is compensated for by positive linear expansion of a temperature compensation member. Since shape memory effect alloy is used for the temperature compensation member, the length of the temperature compensation member can be greatly shortened, and the actuator can be small-sized, light weight and improved in its heat conduction. Also, shape memory effect alloy can be used for temperature compensation members in broader range of temperature by stacking several pieces of the shape memory effect alloy whose transformation temperatures differ from each other.

Abstract: A presure sensor for providing an electrical signal corresponding to pressure in a cylinder of an automotive engine has a rigid load-spreading element rigidly secured to a first surface of a ceramic piezoelectric body by a rigid bonding material precisely conformed to the first surface to be in substantially uniform load-transferring relation to all parts of the first body surface, has a rigid support member rigidly secured to a parallel, opposite surface of the ceramic piezoelectric body by a rigid bonding material precisely conformed to the opposite surface to be in substantially uniform load-transferring relation to all parts of the opposite body surface to form a piezoelectric unit and has a peripheral part of the rigid support member precisely mounted with an interference fit in a bore in a metal component of a mounting structure so that the body of a piezoelectric material and the load-spreading element extend in a cantilever relation at a precisely determined location to be engaged by force applied thr

Abstract: In a conventional quartz crystal resonator, a sacrificial quartz layer attached to the mounting posts and between the active, vibrating quartz layer and the package base reduces mechanical stresses on the active quartz layer caused by thermal expansion coefficient differences. The intermediate quartz layer is a sacrificial layer which acts to maintain the spacing of mounting posts.

Abstract: A device for magnifying displacement of an elongated piezoelectric element adapted to be displaced by application of voltage thereto, including a main frame extending along one side of the piezoelectric element and having a lateral projection for supporting one end of the piezoelectric element with respect to a direction of displacement of the piezoelectric element; a movable member mounted on the other end of the piezoelectric element with respect to the direction of displacement of the piezoelectric element; a first leaf spring fixed at its one end portion to the main frame; a second leaf spring fixed at its one portion to the movable member and disposed in opposed relationship to the first leaf spring; a rocking member fixedly connected to the other end of the first leaf spring and the other end of the second leaf spring and adapted to be rocked by flexing of the first and second leaf springs to be generated by the displacement of the piezoelectric element; a sub frame extending along the other side of the

Abstract: A vibrating force transducer suitable for use in a pendular accelerometer mprises a flat elongated strip of piezo-electric material having end portions arranged for being securely connected to elements which apply a force to be measured along the direction of elongation when the transducer is in service. The strip is fractionated by slits parallel along the direction of elongation and orthogonal to major faces of the strips into a central beam and lateral beams which are in a common plane, the lateral beams carrying electrode means for flexural vibration in the common plane at a resonance frequency indicative of the value of the force applied to the end portions and the central beam carrying a resistive temperature sensor.

Abstract: A resonator assembly comprises a rigid support and a rigid crystal which are rigidly connected along linear segments which have one or more matched thermal characteristics. In a particular embodiment, a thermally matched resonator assembly comprises a Z-cut quartz crystal support, a quartz crystal resonator having an active region and including a crystalline structure oriented relative to X-, Y- and Z-crystallographic axes, which X- and Y-crystallographic axes define an X-Y crystallographic plane; and a rigid connector structure for rigidly connecting the resonator to the support along a segment of a line of a plane parallel to or including the X-Y crystallographic plane, which segment extends across a surface of the resonator and is spaced from the center of the active region of the resonator.

Abstract: This invention pertains to the electroacoustic transducer arts and disclo an improved physical construction therefor in which a honeycomb-like member is used to secure both pressure release and thermal transfer for the converting element.

Abstract: The present invention is directed to a device which simply and efficiently compensates for changes in the volume of a fluid trapped in a fluid-filled cavity between two relatively immovable housings and an elastomeric seal ring. The present invention is particularly useful in an acoustic transducer pad assembly designed for installation on logging tools used in deep boreholes in the oil and gas industry where high temperatures and pressures are experienced at downhole locations. In a presently preferred embodiment, the device comprises a transducer unit housing fixedly secured to a metal wear pad housing with an elastomeric seal disposed therebetween to define a fluid-filled cavity between adjacent portions of the housings and the seal. The seal is disposed in a groove of sufficient size to permit the required lateral expansion and contraction by deformation or extrusion of the seal in order to compensate for the expected changes in the volume of the fluid-filled cavity.

Abstract: A stacked type piezoelectric actuator comprises a main stack of a plurality of electrostrictive strain elements stacked one on another. Each strain element comprises a first piezoelectric element plate having a first direction of polarization and a second piezoelectric element plate having a second direction of polarization. An end electrostrictive strain element is mounted on an end of the stack and has a lower shear strain component during widthwise expansion and contraction of the actuator. The end element includes either a stack of two or more of the first piezoelectric element plates or a pair of first and second piezoelectric element plates when the first piezoelectric element plate has a piezoelectric strain constant d.sub.33 that is less than the strain constant d.sub.33 of the first and second piezoelectric element plates in the main stack.

Abstract: A process of bonding crystalline quartz plates in a plate assembly of a quartz crystal resonator is provided. The plate assembly includes a base plate, a resonator plate, a cover plate, a first silver and indium alloy layer between the base plate and the resonator plate, and a second silver and indium alloy layer between the resonator plate and the cover plate. The process of bonding the plates in the plate assembly includes the steps of depositing in sequence on base plate face and on the cover plate face, a layer of chromium, a layer of silver, and a layer if indium, and also includes the steps of depositing in sequence on two opposite faces of the resonator plate, a layer of chromium, and a layer of silver, and also includes the steps in sequence of sandwiching the resonator plate between the base plate and the cover plate to form a plate assembly, then evacuating the plate assembly, compressing the plate assembly, and heating the plate assembly to about 310 degrees centigrade for several hours.

Abstract: An apparatus for monitoring the curing of a fiber reinforced composite plastic which is cured at temperatures of the order of 350.degree. C. and an ultrasonic transducer assembly useful in the apparatus. The transducer assembly comprises a lithium niobate piezoelectric element having anisotropic coefficients of thermal expansion which is mounted on a metal base of the transducer assembly by means of a layer of structured copper. The structured copper is thermo-compression diffusion bonded to the lithium niobate element and to the metal base, and is compliant in a transverse direction to compensate for differential thermal expansions while affording good electrical and thermal conductivity and good acoustic coupling between the lithium niobate element and metal base.

Abstract: Piezoelectric resonator with maximum sensitivity to external pressure stres.The resonator includes means (2,3) for exerting nonlocalized radial compressive forces uniformly over diametrically opposed peripheral zones of the crystal (1) in which the zones occupy a predetermined sector 2.alpha. of at least approximately 110.degree. and are oriented so that the bisectors (A--A) of the peripheral zones form a predetermined angle .psi. with the crystallographic X axis of the crystal.Depending on the value of .psi., it is possible to minimize or, on the contrary, maximize the sensitivity of the resonator to the external pressure stresses.

Abstract: A piezoelectric motor actuated amplifier mechanism that utilizes a pair of saggital linkages having one relatively fixed saggital midpoint and joined at their end points to obtain a doubled amplification factor output from one relatively movable saggital midpoint. Thermal compensators are employed between the piezoelectric actuator and the saggital linkages to stabilize the amplifier throughout a wide range of temperatures.

Abstract: An amplifier mechanism which utilizes the electroexpansion characteristics of a pair of piezoelectric stack motors pivotally mounted in a rigid frame to directly contact and move with the output actuator element of the mechanism. The stack motors are mounted in opposition in a saggital arrangement so as to provide counterbalanced lateral forces that are manifested in longitudinal amplified movement of the output actuator element.

Abstract: A contact heater arrangement is disclosed for a piezoelectric effect crystal resonator. The piezoelectric effect crystal element may be an SC cut quartz crystal disc having electrodes affixed to one side thereof to generate a lateral field in the crystal disc. The contact heater element is applied to the side of the crystal element opposite the side on which the electrodes are affixed. The particular pattern of the heater leaves the center of the crystal element exposed for frequency adjustment purposes. Locating the heating element and electrodes on opposite sides of the crystal element generates a constant temperature which has been found effective to uniformly heat a piezoelectric effect crystal element, and with appropriate control circuitry, allows for temperature stabilization of the crystal element.

Abstract: The accelerometer comprises: a body intended to be fixed on a component, such as an internal combustion engine cylinder head, whose accelerations or vibrations are to be detected; a piezoelectric element prestressed between the body and a seismic mass; and flexible electrical conductor means between two opposite faces of the piezoelectric element and the terminals of an electrical connector mounted on the accelerometer body, provision being moreover made for an electrical connection between the respective faces of the piezoelectric element and the adjacent parts of the accelerometer. The electrical connector means is mounted on the body of the accelerometer by means of the damping means capable of reducing or suppressing the mechanical transmission of the vibrations or accelerations from the accelerometer body to the connector.