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: This invention relates to a method of testing multi-channel array pulsed droplet deposition apparatus (10) comprising a multiplicity of parallel channels (12) each with pulse imparting means for expelling droplets therefrom. The apparatus is located opposite a test module (20) having detecting elements (21) with channels of the apparatus opposed and close to the respective elements. Coupling fluid (23) fills the channels (12) to be tested and the space between the apparatus and the test module. Test signals are applied to impart energy pulses to the fluid in the channels opposite the detecting elements so that signals are passed to those elements by way of the fluid which are evaluated to assess the channel performance. Various forms of the detector elements and the apparatus are disclosed.

Abstract: A weight measuring device includes two piezoelectric elements. The first piezoelectric element induces vibration in an object to be measured, and the second one detects the reaction force of the object generated by the vibration. This force is detected by a voltage monitor circuit as an output voltage from the second piezoelectric element. From the voltage which has been detected, the weight of object is determined. The device further includes an absorbing element to absorb unnecessary piezoelectric strain in reaction force generated when the object vibrates. The invention provides a compact weight sensor which can be produced at low cost, and which can measure weight with high accuracy.

Abstract: A pointing device for use in moving a cursor displayed on a display, includes a pressure sensing sheet including first through fourth pressure detection elements and a base member mounted on the pressure sensing sheet. The base member is provided with first through fourth protrusions formed on its under surface opposite to the pressure sensing sheet in facing relation to the first through fourth pressure detection elements, respectively. The base member is provided with an operation shaft formed on an upper surface of the base member which projects upwardly therefrom. The device further comprises a cap member coupled to the operation shaft of the base member.

Abstract: A device for determining which zone on a target has been struck by an object. The device is made of a frame, and a flexible support means which is mounted on the frame, and is disposed in the path of a moving object. A transducer made of piezoelectric film, coated with a conductive coating on each of its surfaces to form electrodes, is mounted on the flexible surface. Attached to the electrodes of the transducer are leads which transmit electrical pulses to a signal processing unit. An object striking the target produces an electrical pulse which is translated by the signal processing unit and which determines the zone on the target which was struck by the object.

Abstract: A vibrating disc transducer assembly suitable for accurately measuring high pressures utilizes a transducer having a vibratory disc that is preferably fabricated from silicon and excited to vibrate in the thickness-shear mode. The excitation is accomplished by placing the resonator in a magnetic field and passing an electric current through electrodes on opposite sides of the disc. The transducer is supported in a housing that communicates with the medium whose pressure is being measured.

Abstract: A pressure micro-sensor is formed by a sandwich of three silicon plates in contact by their periphery, with an interposed insulating layer in order to define an internal cavity. The lower plate (2) includes a thinner region (21) forming a diaphragm, on its internal side. The intermediate plate (1) includes a peripheral region (11) forming a frame coupled to the upper and lower plates by a silicon oxide layer (24, 25), a first stud (13) mounted onto the thinner region of the lower plate, a second stud (14) mounted onto a thick region of the lower plate, and a silicon beam (15) forming a resonator and disposed between the upper surfaces of the first and second studs in front of the upper plate (3). A first electrode (32) is connected to the upper plate, a second electrode (33) is connected to the frame and a third electrode (31) is connected to the second stud.

Abstract: A dual crystalline resonator package comprises either (1) two crystalline bodies, in adjoining cavities of which bodies a crystalline temperature resonator and a crystalline reference resonator are respectively connected and which bodies are directly connected together, or (2) such two crystalline bodies in conjunction with a third crystalline body which is connected directly between the two first-mentioned bodies and to opposite sides of which third body the resonators are connected so that the resonators extend therefrom into the cavities of the two first-mentioned bodies. Either of these embodiments can be used for generating temperature data signals in a high pressure, high temperature well wherein the respective embodiment is lowered and exposed to such high pressure and high temperature. A modification of the second embodiment eliminates one of the resonators and the respective body having the cavity into which the eliminated resonator would otherwise extend.

Abstract: The air pressure variation detector comprises a base plate having a through hole or a cavity, a piezoelectric element fixed to the base plate so as to locate above the through hole or the cavity and formed in a strip-like shape having a width narrower than the inside width of the through hole or the cavity, an impedance converter circuit consisting of a field effect type transistor and a leak resistor, and an electrically conductive accomodating container having a vent hole. An output terminal of the piezoelectric element is connected to a gate of the field effect type transistor, and the leak resistor is connected between the gate and a ground terminal of the piezoelectric element. This air pressure variation detector is simple in its composition and can detect with high accuracy slight variations of air pressure in the enaudible region.

Abstract: A method for making a piezoelectric stack. The stack includes a plurality of piezoelectric discs interleaved with a plurality of electrodes. Each disc has two opposing surface facets. Each electrode has a thin planar section having two opposing planar surfaces. The planar section is adapted to contact a substantial portion of the surface facets of two adjacent discs. The method includes the steps of cutting a cylindrical piezoelectric ceramic slug into discs. The two opposing surface facets of each disc is formed substantially parallel to one another and have a predetermined surface roughness. The method includes the steps of applying a conductive layer to the surface facets and etching the planar surfaces of the electrodes with an acidic solution. The etching step causes the planar surfaces to achieves a surface roughness similar to that of the predetermined surface roughness of the disc surface facets.

Abstract: A pressure transducer including a first pressure crystal, a second temperature crystal, a third reference crystal and associated electronics. All three crystals resonate in the thickness-shear mode.

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 sensor containing at least one piezoelectric transducer element is operated via a common, single signal line in both possible operating modes--first, at low frequencies as a measuring element for a mechanical quantity upon utilization of the direct piezoeffect and, second, at higher frequencies as a piezoelectric resonator upon utilization of the inverse piezoeffect for electrical excitation of mechanical oscillations and of the direct piezoeffect for generating the piezoelectric reaction. A high-frequency signal (u.sup.HF, u.sub.F) that describes the resonant characteristic and a lower-frequency signal (u.sub.NF, u.sub.Q) that describes the mechanical influence are generated from the measured signal on the signal line. The faultless function of the sensor together with the appertaining measuring amplifier, for example, can thus be monitored immediately during a measurement with the sensor or a simultaneous measurement of two different quantities can be undertaken.

Abstract: A pressure transducer comprises a quartz crystal having an orientation within a range of angles between about -25.degree. and about -45.degree. relative to the Z axis of X, Y and Z crystallographic axes. Such a pressure transducer provides a useful pressure response at pressures and temperatures above those of the operating ranges of pressure transducers using AT-cut or BT-cut quartz crystals.

Abstract: The first embodiment of a piezo electric transducer shown in this application has a housing, an actuator, piezoelectric material, a first fixed contact and a second fixed contact. The actuator overlies the piezo-electric material and is attached to the inner surface of the housing. The piezoelectric material overlies the spaced first and second fixed contacts whereby distortion of the piezoelectric material by the actuator causes a current to flow between the first and second fixed contacts. In the second embodiment the piezoelectric material is attached to the inner surface of the housing. In a variation of the first and second embodiments, the piezo electric material is sandwiched between first and second dome portions. The first dome portion is engaged to a first fixed contact and the second dome portion is engaged to a second fixed contact.

Abstract: A device is disclosed for detecting the presence and direction of air flow through a passageway having a first opening and a second opening for air to flow therethrough in either a first direction or a second direction. The device comprises a piezoelectric sensor located within the passageway. A flow director is provided within the passageway for directing air flow through the passageway for impingement upon the sensor. The sensor generates a first electrical signal when air flows through the passageway in the first direction and a second electrical signal when air flows through the passageway in the second direction. A discriminator is electrically connected to the sensor for receiving the first and second electrical signals and for discriminating between the two signals to identify the direction of air flow through the passageway.

Abstract: A piezoelectric device includes a first electrode, a second electrode disposed in opposing, spaced relation to the first electrode, a ferroelectric liquid crystal interposed between the first and second electrodes, a first alignment layer formed between the first electrode and the ferroelectric liquid crystal, and a second alignment layer formed between the second electrode and the ferroelectric liquid crystal.

Abstract: A pressure sensor for use in an internal combustion engine includes a diaphragm member having a cylindrical part and a pressure receiving part which is subjected to an axial motion in an axial direction of the diaphragm member when a pressure in an external environment is applied to the pressure receiving part, a pressure detection member having pressure distributing parts and a piezoelectric part for generating a signal indicative of the applied pressure when it is stressed in response to the axial motion of the pressure receiving part, and a pressure transfer member for transferring the motion from the pressure receiving part to the pressure detection member, the pressure transfer member including a spherical member capable of rolling relative to the diaphragm member in a direction perpendicular to the axial direction of the diaphragm member at a position between the pressure receiving part and the pressure detection member.

Abstract: An ultrasonic sensing array having ultrasonic transducer elements formed on a micromachined single-crystal semiconductor wafer provided with a deep recess under each transducer. Etch-altering dopants are diffused into the water to form rimmed support structures for dielectric stress-balanced elements. Composite dielectric layers are grown on both surfaces of the wafer. One composite layer serves as a diaphragm underlying the transducer elements. The other composite layer serves as a mask for etching away the substrate under each transducer element to form the deep recess while leaving the support structures and diaphragm layer. The resulting hollow or recess under each transducer element reduces the parasitic capacitance between the transducer and support substrate. The transducer elements are made by forming conductive bottom plates on the dielectric diaphragm layer, adding a piezoelectric polymer layer and thereafter forming the conductive top plates.

Abstract: An ultrasound sensor has a piezoelectric foil polarized in at least in one region, a signal electrode arranged at one side of the piezoelectric foil, and comprises a shell electrode arranged at the other side of the piezoelectric foil. The piezoelectric foil, the signal electrode and the shell electrode are component parts of a multilayer structure wherein the signal electrode and the shell electrode are separated from the piezoelectric foil by a dielectric coupling layer, and the signal electrode and the polarized region of the piezoelectric foil overlap in a region forming a pressure-sensitive sensor surface.

Abstract: Biasing electrodes on a piezoelectric acoustic vibrator alter the sensitivity of the acoustic vibrator and can be used to compensate for external stresses applied to the acoustic vibrator. The biasing electrodes and the circuitry providing electric signals to them are separate from the RF circuitry feeding the RF signal electrodes of the acoustic vibrator. Biasing electrodes can be used on bulk acoustic wave devices or surface acoustic wave devices. The biasing electrodes can be energized by a static D.C. voltage source, or can be used in a dynamic biasing arrangement to provide instantaneous compensation for changing environmental conditions.

Abstract: A piezoelectric device includes a first electrode, a second electrode disposed in opposing, spaced relation to the first electrode, a ferroelectric liquid crystal interposed between the first and second electrodes, a first alignment layer formed between the first electrode and the ferroelectric liquid crystal, and a second alignment layer formed between the second electrode and the ferroelectric liquid crystal.

Abstract: A piezoelectric switch assembly and method of manufacture. A piezoelectric module is provided which is comprised of a carrier disk and a wafer of piezoelectric material disposed thereon, with electrical leads connected thereto. The piezoelectric module is disposed inside a hollow recess formed in a switch plug, with the periphery of the carrier disk supported on a rim thereof. A disk of compressible material is disposed between the body of the plug and the piezoelectric module. The switch plug is inserted into a hollow chamber formed in a switch insert, said switch insert having a pressure receiving front wall. A front member is provided which is formed with an aperture for receiving the switch insert. Pressure on the pressure receiving front wall of the socket causes deformation of the piezoelectric wafer to generate an electrical signal which is received by circuitry attached to the electrical leads to effect one or more preselected switch functions.

Abstract: A quartz crystal gas pressure sensor senses a range of pressures within a gaseous environment, such as from 0.1 millibar to 1 bar. The sensor includes a quartz crystal connected to manifest a piezoelectric effect upon excitation by an alternating electric field and communicating with the gaseous environment, an oscillator circuit connected to the quartz crystal for generating the alternating electric field and including a feedback circuit for providing a signal for self-excitation at the resonant frequency of the crystal as well as indication of vibrational amplitude of the crystal as a function of gas pressure within the gaseous environment, and an indicator circuit connected to the feedback circuit for converting the electrical signal into an indication of the gas pressure sensed within the gaseous environment. A gas pressure measuring method is also described.

Abstract: A simplified heterostructure charge transport device has a GaAs transport layer that is the top layer of the device, deposited on an (Al,Ga) As barrier layer for vertical confinement of charge packets. Confinement at the top surface is provided by pinning of the conduction band surface states.

Abstract: A pressure 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 piezoelectric material and the load-spreading element extend in cantilever relation at a precisely determined location to be engaged by force applied throu

Abstract: A vibrating type pressure measuring device having good shock wave proof measuring characteristics, high frequency response, good temperature characteristics, and can be readily miniaturized, wherein pressure to be measured is applied to a silicon diaphragm provided in an internal vacant space of a housing, and a magnetic field is applied by a DC current magnetic field applying device to a vibrator beam arranged in the inside of the diaphragm, with a gap therebetween kept in vacuum, and fixed to the diaphragm at both ends, and detects the changes in natural frequency of the vibrator beam caused by the pressure to be measured. The diaphragm and/or vibrator beam are constructed so one or the other or both have rough or uneven surfaces so as to prevent any adhesion therebetween.

Abstract: A ferroelectric liquid crystal touch panel includes a ferroelectric liquid crystal panel including counterposed electrodes and a ferroelectric liquid crystal positioned between the electrodes; a position detector for detecting a pushed position on the ferroelectric liquid crystal through the electrodes by means of an electromotive force generated when the ferroelectric liquid crystal is pushed; a display control circuit for controlling a display state of the ferroelectric liquid crystal through the electrodes; a sound generation control circuit for supplying a sound generation signal to the electrodes so that the ferroelectric liquid crystal panel generates a sound in correspondence thereto; and a selection circuit for selectively connecting the position detector, the display control circuit and the sound generation control circuit to the electrodes.

Abstract: A piezoelectric transducer useful for example as a sound source or a strain detector includes a ferroelectric liquid crystal sealed between two baseplates with electrodes and alignment layers on the inner facing surfaces of the baseplates. One of the baseplates is thicker than the other, or is of a different material, so that the two baseplates have different flexural rigidity.

Abstract: A force pad is provided with a flexible polymeric piezoelectric transducer strip mounted on the perimeter of a resilient support pad for measuring force and change in force in industrial, medical and sports applications.

Abstract: An integral connector for a piezoelectric solid state motor stack having a plurality of ceramic disks interleaved with electrodes. Lead wires connect the electrodes to a source of electrical potential. A housing, for containing the motor stack, includes a connector body mounted to one end portion of the housing. A plurality of contact pins mounted to the connector body are adapted to be connected to the source of electrical potential. A structure defines a path for guiding the lead wires between the contact pins and the electrodes, wherein the lead wires exit the combination of the ceramic disks and electrodes along first and second parallel longitudinal axes separated by a first distance, and attach to the pins which are located along third and forth parallel longitudinal axes separated by a second distance, wherein the first distance is different from the second distance.

Abstract: The present invention is a device for characterizing pressure distributions on a rigid surface with respect to at least one reference (x) axis. The device includes a substrate electrode disposed on the rigid surface for which the pressure distribution is to be characterized. An electrically conductive material may form the substrate electrode, or where the rigid surface itself is electrically conductive, that rigid surface may form the substrate electrode. A piezo film is disposed on and overlying the rigid surface. A sensor electrode is disposed on and overlying at least part of the piezo film. In one form of the invention the sensor electrode of a measurement cell is a composite electrode including at least two electrically isolated portions.

Abstract: A high-performance single-crystal silicon tactile imaging array organized in a X-Y matrix of capacitor elements. Metallic column lines are formed on a glass support substrate, while the row lines are formed from a contiguous chain of doubly-supported bridge structures, with one such structure for each sensing element. All of the bridge structures are simultaneously fabricated from a single-crystal silicon semiconductor wafer using a two-step boron diffusion process, followed by a silicon-to-glass electrostatic bonding step and subsequent unmasked wafer dissolution. Each bridge structure has a thick center plate for the sense capacitor supported by thinner beams connected to adjacent row single-crystal silicon support rails bonded to the glass substrate. The force sensitivity and maximum operating range of the tactile imager can be selected over a very wide range by appropriately setting the dimensions of these thinner support beams.

Abstract: An energy converter includes a vibrating structure formed of metallic or ceramic material and including a spherical member having a spherical opening located concentrically therein. The vibrating structure is cooled by liquid hydrogen and the spherical opening contains a spherical outer member formed of ceramic and containing piezoelectric crystals embedded therein. An intermediate spherical member formed of an insulator material is positioned concentrically within the outer spherical member, and an inner sectional spherical member is positioned within the intermediate spherical member. The sectional spherical member is comprised of a plurality of laminated sections, each including inner, outer, and intermediate elements. Suitable conductors connect the innere and outer elements of the sectional spherical member with a source of electrical current. A spherical core member is positioned interiorly of the sectional spherical member and is formed of a non-fusion material (does not heat up on impact).

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: An impulse sensor comprises a Piezo electric element disposed intermediate a thin end wall and a thick end wall of a container vessel in a pressurized relationship, wherein an impulse transmitting member extends from the thin end wall, which impulse transmitting member transmits impulses exerted onto the extremity thereof to the Piezo electric element.

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 vibrating type transducer wherein an H-shaped vibrator, formed integrally with a silicon substrate and having a hollow chamber provided therearound, is kept self oscillating at its natural resonance frequency together with an amplifier. A physical quantity, such as force, pressure, differential pressure, or the like, which is applied to the silicon substrate is detected by a change in the natural frequency arising at the vibrator corresponding to the physical quantity. The invention also includes a method for manufacturing such transducer using a semiconductor technique, including steps for keeping a vacuum internally in the hollow chamber, imparting an initial tension to the vibrator, and then operating the amplifier to have stable self oscillation.

Abstract: In the present pressure measurement process the damping signal of a tuning fork quartz manometer, which is a measure of the prevailing pressure, is so combined with the correction value proportional to the resonant frequency that a measurement result is obtained, which is independent of any contamination of the tuning fork quartz. Apart from the resonant frequency (f.sub.R) of the measuring quartz (11), preferably also the resonant frequency (f.sub.R ') of a reference quartz (21) kept at constant pressure is determined. Thus, the damping signal (R.sub.S) can be corrected by a correction value proportional to the difference between the two reference frequencies (R.sub.R '-f.sub.R), which is substantially temperature-independent.

Abstract: The tuning fork quartz manometer has a tuning fork quartz (2) mounted in a protective casing (3) which is in turn part of a self-oscillating feedback circuit. According to the invention the protective casing (3) is inserted by means of a sealing compound (4) or directly into a hosing (5) of a measuring head (1,6) or a mounting support (15a, 20') so that the mounting support can in turn be inserted in the measuring head (1,6) and, as desired, an ideal rigid or elastic suspension is provided. A measuring circuit (20) is located directly in the measuring head close to the tuning gork quartz (2) and is thermally coupled to the latter. The measuring circuit (20) preferably has a temperature correction network (R.sub.1, R.sub.2, 22) high frequency coupled from the feedback circuit containing the tuning fork quartz.

Abstract: A process for measuring pressure, preferably vacuum is described. The measuring signals from a heat conduction gauge and the measuring signals from a gas friction gauge are processed to a common measuring signal preferably by multiplication. They are linearly superimposed or added. The heat conduction gauge is preferably a Pirani gauge and the gas friction gauge is preferably a tuning fork quartz gauge.

Abstract: A monolithic resonator for a vibrating beam accelerometer is provided which comprises an outer structure including a mounting structure, a proof mass structure, a plurality of flexure beams extending between the mounting and proof mass structures; and an inner structure including first and second isolator masses, first and second isolator beams connected to one portion of the isolator masses, respectively, and a vibrating beam extending between other portions of the isolator masses. The monolithic resonator is non-planar in that the outer structure has a thickness greater than said inner structure.

Abstract: The present invention relates to an angle sensor for musical tone control which controls a musical tone in response to changing angles at an articulation of the human body. Both ends of a pair of plate members are coupled pivotally and movably around an axis parallel to both faces of plate members. This pair of plate members are attached on the interior side of articulation of the human body by attaching means to generate a signal in response to the bending motion of the articulation. Thus, a musical tone control signal in response to the bending angles is outputted from detecting means which is placed on the plate members to control musical tone.

Abstract: An oscillating crystal force transducer and method of making the same are provided, the transducer comprising support structure, a plate-shaped piezo-electric crystal having opposed sides and a peripheral edge extending between the opposed sides, and two seating members carried by the support structure and respectively engaging the peripheral edge of the crystal and arranged to apply a force to the crystal along a line extending through the crystal from one of the seating members to the other of the seating members, the support structure comprising a looped spring member having opposed ends spaced from each other to define the mouth of the looped spring member and respectively carrying the seating members whereby the crystal is disposed in the mouth of the looped spring member between the seating members thereof.

Abstract: A sensor apparatus includes a pressure sensor, a reference device and a temperature sensor collocated within a common environment. The reference device and the temperature sensor are constructed to have temperature response times matched to the temperature response time of the pressure sensor to compensate for temperature gradients produced either by external heating or by pressure-volume heating.

Abstract: An indication is given of a method, and simultaneously of an apparatus, for measuring pressures and forces acting on arbitrarily shaped bodies. Employed in this connection is a piezoelectric film, which is provided on both sides with a metal coating. The piezoelectric film is bonded onto the body, and a charge variation of the piezoelectric film is evaluated in an evaluation unit, and employed as measure for the force acting on the body, or for the pressure. The metal coating (5) is partially removed from one side of the piezoelectric film (2) to form individual sensors (3, 4). Each individual sensor (3, 4) is coupled to the evaluation unit (10) via an electrical connection (8, 9). The other side of the piezoelectric film (2) with the continuous metal coating (5) serves as electronic shield and is connected to earth (7). The charge variation of each individual sensor (3, 4) serves as measure for the local force or the local pressure.

Abstract: An improved sensor for detecting vibrations uses a flexible moving beam supported by two flexible leg members. The flexible moving beam can be moved in two directions. A protrusion extends from near one end of the flexible moving beam. The protrusion is placed against a transducer element 22 which is against a rest element 24 . When the moving beam is moved parallel to its length, the protrusion is pushed against the transducer element 22 and against the rest element 24, thereby generating electrical signals. When the moving beam detects vibrations in a direction perpendicular to its length, the protrusion is rotated upward and outward and pushes against the transducer element 22, causing the generation of electrical signal. The improved sensor is particularly adapted for detecting vibrations from a stringed musical instrument.

Abstract: A double tuning fork type force transducer comprising two identical parallel branches fastened at their ends to two coupling members adapted to vibrate in bending mode and in phase opposition in response to imposed vibrational loads with an intrinsic frequency representative of the amplitude of a force F applied longitudinally to the coupling members is laminated; it comprises two identical metal leaf springs of constant thickness forming said branches and comprising ends of larger width than said branches and held apart by two metal spacers both having the same thickness, these spacers and these ends being fastened within said coupling members and having substantially the same external profile.

Abstract: A strain gage comprising a strained-layer superlattice crystal exhibiting piezoelectric properties is described. A substrate upon which such a strained-layer superlattice crystal has been deposited is attached to an element to be monitored for strain. A light source is focused on the superlattice crystal and the light reflected from, passed through, or emitted from the crystal is gathered and compared with previously obtained optical property data to determine the strain in the element.

Abstract: The present invention relates to an angle sensor for musical tone control which controls a musical tone in response to changing angles at an articulation of the human body. Both ends of a pair of plate members are coupled pivotally and movably around an axis parallel to both faces of plate members. This pair of plate members are attached on the interior side of articulation of the human body by attaching means to generate a signal in response to the bending motion of the articulation. Thus, a musical tone control signal in response to the bending angles is outputted from detecting means which is placed on the plate members to control musical tone.