Abstract: The transformer (1) includes a body (2) made of piezoelectric material having an outer lateral surface (E) in the shape of a circular cylinder. Primary electrodes (5, 7, 10, 12, 17, 19, 22, 24) are arranged on the body (2) so that, when the primary voltage (Up) which is applied thereto has a determined frequency (fr), the outer lateral surface (E) alternately takes the shape of a first and a second elliptical cylinder, the major axes of these latter being perpendicular to each other and perpendicular to the axis (A) of the circular cylinder.This vibration mode of the body (2) has a lower fundamental resonance frequency than that of the vibration mode of known transformer bodies having the same space requirement. The transformer (1) is thus well suited to being used in devices where the available space is limited for providing a relatively high AC voltage but having a relatively low frequency.

Abstract: A piezoelectric transformer is described that features high energy-conversion efficiency and high reliability. Four driver piezoelectric ceramic plates are provided on the upper and lower surfaces at both ends of a generator piezoelectric ceramic plate having a rectangular shape, the driver piezoelectric ceramic plates having the same width and one-third the length of the generator piezoelectric ceramic plate. Vibration is not hindered and the energy-conversion efficiency is therefore increased in this construction because the draw-out positions of the four input electrodes and three output electrodes are all positioned at the nodes of mechanical vibration. In addition, the reliability of lead wire connections is improved because vibration places no load on the lead wires. Finally, input capacitance and step-up capabilities can be raised by adopting a multilayer construction for the driver piezoelectric ceramic plates.

Abstract: A piezoelectric transformer has a plate shaped piezoelectric member including a driving section disposed at one portion of the piezoelectric member including one end thereof and a power-generating section at the other portion of the piezoelectric member including the other end thereof. The driving section includes driving electrodes and a portion of the piezoelectric member which is polarized in the thickness direction. The power-generating section includes a power-generating electrode and a portion of the piezoelectric member polarized in the longitudinal direction. At least one polarization electrode which is exposed in part on a surface of the piezoelectric member is provided between the driving section and the power-generating electrode.

Abstract: A laminated step-down piezoelectric transformer has a driving portion 11 and an electric power generating portion 12 disposed on both end portions of an elongated plate. These portions are formed by alternately laminating piezoelectric members 111 and internal electrodes 112 . . . interposed by an insulating portion respectively. The piezoelectric members 111 of the driving portion 11 are thicker in thickness than that of the electrical power generating portion 12. The transformer is driven with a second-order mode in the longitudinal direction so that the transformer has a high transformation efficiency. Impedance matching can be realized easily. The piezoelectric transformer is safe in operation by separating the input and the output from each other.

Abstract: There is disclosed a device for applying vibrations to a cantilever used in an atomic force microscope. The cantilever has a base portion, and a probe is attached to the front end of the cantilever. The device has a piezoelectric plate subassembly consisting of first and second piezoelectric plates having junction faces cemented together. A piezoelectric plate subassembly support portion supports a part of the second piezoelectric plate. A voltage is applied to the piezoelectric plates so that one of them is stretched vertical to the junction faces and that the other is contracted vertical to the junction faces.

Abstract: A piezoelectric transformer has input and output terminal electrodes (12c, 12d, 13c, 13d) exposed on a bottom surface thereof. The terminal electrodes are mechanically and electrically connected to connection portions (15a-15d) of a flexible printed circuit (18) for connecting with an external circuit. The transformer is held between a base element (21b, 22) and a cover (21a, 23, 25) coupled to each other. The base element may be a circuit board on which the transformer should be mounted.

Abstract: The invention relates to a circuit arrangement with a piezoelectric transformer having two electrodes arranged on the primary side of the transformer and such a piezoelectric transformer itself. Piezoelectric transformers of this type are used, for example, for the power supply or control of lamps or electron tubes. For controlling such a piezoelectric transformer directly on the primary side by a most frequently available DC voltage, instead of an AC voltage as is customary, according to the invention a DC voltage source is connected to the electrodes and a switching device is provided for interrupting the supply of voltage to at least one electrode, the positions of the switching device being dependent on the state of expansion of the primary side of the transformer. The switching device is thus periodically closed and opened, the applied DC voltage is thus interrupted periodically.

Abstract: An electronic apparatus that performs switching with the use of a piezoelectric element comprises a piezoelectric element 11, a first monitor electrode 15, and a second monitor electrode 16, the latter two being provided thereon and intended to output electric shock signals that are generated when a shock has been applied to the piezoelectric element 11 to thereby distort it. Whereby, a shock is applied to the electronic apparatus that contains the piezoelectric element 11 and a shock is applied to the built-in piezoelectric element 11. This makes it possible to output for the purpose of controlling the operation of the respective functions an electronic shock signal that is generated when the piezoelectric element 11 is distorted. As a result, it is possible to reduce the number of switch parts for, and hence the size of, the electronic apparatus and reduce the amount of time and labor for performing the switching operation by utilizing the piezoelectric effect of the piezoelectric element.

Abstract: A piezoelectric resonator (10) includes a single crystal elongated plate (12) having a transverse extensional mode of oscillation. Two sets of split electrodes (20,22,30,32) are provided on the surfaces (14,16) of the plate (12) to define two acoustically coupled oscillating regions (24,26) therebetween. The oscillating regions (24,26) present a similar inductance and have similar performance to allow the use of the resonator (10) in a double-ended electrical transformer circuit (100). An AC source (112) drives non-opposing top and bottom electrodes of the resonator (110). The remaining electrodes are coupled with shunt capacitors to provide two resonant LC circuits with the resonator (110) so as to provide a voltage gain for driving a load.

Abstract: An AC/DC converter of the present invention includes a transformer implemented by a piezoelectric transformer. Power fed from a commercially available power source (14) is converted to a DC voltage by rectification and smoothing. The DC voltage is transformed to a high frequency (about 100 kHz) pulse voltage by switching FETs (Field Effect Transistors) (5) and (6). The pulse voltage is applied to the input of a piezoelectric transformer (9). The transformer (9) has its vibration mode and dimension selected such that the resonance frequency of the transformer is substantially identical with the frequency of the above pulse wave. A high frequency AC voltage is produced from the output side of the transformer (9). The AC voltage is transformed to a DC voltage by rectification and smoothing and then fed to a load resistor (13). The piezoelectric transformer is easy to miniaturize, compared to an electromagnetic transformer. The entire AC/DC converter can therefore be reduced in size.

Abstract: A piezoelectric transformer includes at least a pair of monitor electrodes for monitoring unbalanced vibration of the piezoelectric element. The transformer also has a plurality of input electrodes for a transformer input signal and a pair of output electrodes for a transformer output signal. While driven by the input signal to produce the output signal, the piezoelectric transformer produces a pair of monitor signal components at the monitor electrodes to individually indicate vibration components produced in the piezoelectric transformer collectively as a state of unbalanced operation of the transformer.

Abstract: A piezo-electric transformer comprising a piezo-electric body (PEB) including a driving region having input electrodes (1, 3) and at least one driven region having output electrodes (E11). These regions have opposite faces with at least one of the regions comprising a number of sections polarized in a direction perpendicular to the opposite faces and one pole of each section being connected to an opposite pole of another section by electrically conductive elements (2, 1', 2') in such a way that the sections form a series arrangement.These sections are in a very simple way effectively arranged in series, thereby increasing the input impedance of the piezo-electric transformer. Because the sections are polarized in opposing directions the electrically conductive elements can be of a very simple construction which do not require external conduction wires.

Abstract: A piezoelectric transformer includes a plate-shaped piezoelectric member having a driving section located at a first portion of the piezoelectric member including a first end and a power-generating section located at a second portion of the piezoelectric member including a second end. The driving section is made by repeatedly and alternately laminating a driving electrode and a portion of the piezoelectric member which is polarized in the thickness direction. The power-generating section includes a power-generating electrode and a portion of the piezoelectric member which is polarized in the longitudinal direction. In the piezoelectric transformer, at least one of the driving section and the power-generating section has an area which is near a boundary between the driving section and the power-generating section which has a lower degree of polarization than the degree of polarization in areas spaced away from the boundary between the driving section and the power-generating section.

Abstract: A power supply including a piezoelectric transformer mounted and electrically connected to a defined board region of a printed circuit board having circuit components for forming the power supply together with the piezoelectric transformer. The transformer has FPC for connecting the transformer and the printed circuit board and is bound together with the board region by a wrapping sheet. In an embodiment, the board region is defined by a slit through which the wrapping sheet is wrapped. In another embodiment, the FPC has lugs standing up thereon to connect with the electrodes of the transformer. In another embodiment, a hard plate supports and covers the FPC and the transformer on the printed circuit board. In the other embodiment, the FPC is formed into a cover case and covers and holds the transformer element when is fixed to the printed circuit board.

Abstract: A piezoelectric vibrator having three parallel vibrator arms formed from piezoelectric material in which dielectric polarization is generated through the application of electric fields extending widthwise between first electrodes formed on top surfaces thereof and between second electrodes formed on bottom surfaces, and also between the first and second electrodes through the piezoelectric material, such that a portion of the dielectric polarization occurs at the surfaces of the vibrator arms, and a portion also occurs within the vibrator arms. When ac driving voltages are applied to the electrodes, the vibrator arms vibrate at large vibration amplitudes due to strains created in the portion of dielectric polarization within the vibrator arms.

Abstract: In a piezoelectric transformer having a piezoelectric body in polarized condition, input electrodes provided on the surface of the piezoelectric body and applied an alternating voltage of a frequency depending upon the resonance frequency of the piezoelectric body and a leading electrode provided on the surface of the piezoelectric body and taking out a voltage depending upon vibration of the piezoelectric body, and a grounding electrode is further provided on the surface of the piezoelectric body and electrically isolated from the input electrode and taking out output voltage in cooperation with the leading electrode by forming a pair, depending on the vibration of the piezoelectric body. Thus, even when an alternating voltage having a frequency equal to the resonance frequency of the piezoelectric body, respective junctions have sufficient strength against vibration.

Abstract: A wafer with a reversed domain is prepared for two piezoelectric single crystal plates 11 and 12 having about the same thickness as each other by using direct bonding without any adhesive. Then, driving electrodes 13 are formed on two principal planes of the wafer with a reversed domain to provide a piezoelectric resonator. A piezoelectric resonator having the structure with a reverses polarization and using odd-order vibration modes vibrating with a fundamental wave has a wavelength of a thickness thereof suppresses scattering of the thickness of the domains with a reversed polarization. In the direct bonding, the axes of the spontaneous polarization of the two piezoelectric single crystal plates are reverse to each other and crystalline axes other than the axes of polarization are shifted intentionally by an angle other than zero. Thus, spurious modes are suppressed in a simple way.

Abstract: A piezoelectric transformer has a piezoelectric substrate having first and second main faces. The substrate has first and second primary-side regions and a secondary-side region in its longitudinal direction in this order. The first region has a length of a half wavelength of stress distribution at the time of resonance in the longitudinal direction and has either positive or negative stress. The second region has a length of a half wavelength or less of the stress distribution and has either positive or negative stress. First and second electrode are respectively disposed on the first and second main faces in the first primary-side region, and the substrate between the first and second electrodes is polarized in the thicknesswise direction. Third and fourth electrodes are respectively disposed on the first and second main faces in the second primary-side region, and the substrate between the third and fourth electrodes is polarized in the thicknesswise direction.

Abstract: A piezoelectric element includes an internal electrode embedded in a piezoelectric ceramic body so as to extend in a longitudinal direction of the body. First to third surface electrodes are formed on upper and lower surfaces of the piezoelectric ceramic body in respective first to third portions along the longitudinal direction. Connecting electrodes are formed to connect the first to third surface electrodes with each other. The first to third portions are polarized so that the second portion is polarized opposite to the polarization of the first and third portions, and regions located above and below the internal electrode are polarized in opposite directions in the respective ones of the first to third portions.

Abstract: A piezoelectric transformer has a plate shaped piezoelectric member including a driving section disposed at one portion of the piezoelectric member including one end thereof and a power-generating section at the other portion of the piezoelectric member including the other end thereof. The driving section includes driving electrodes and a portion of the piezoelectric member which is polarized in the thickness direction. The power-generating section includes a power-generating electrode and a portion of the piezoelectric member polarized in the longitudinal direction. At least one polarization electrode which is exposed in part on a surface of the piezoelectric member is provided between the driving section and the power-generating electrode.

Abstract: A piezoelectric resonator has a base member formed by laminating a plurality of piezoelectric layers and electrodes. The base member is polarized in different directions at both sides of each electrode. Electrodes are alternately covered by a first insulating film and a second insulating film, respectively, at both sides of a groove formed in the base member. The first insulating film covers electrodes which are not covered by the second insulating film, and vice versa. External electrodes are formed at both sides of the groove on the base member and the internal electrodes are connected to the external electrodes. A support member made from an electrically conductive material is provided at the approximate centers of the external electrodes.

Abstract: A piezoelectric ceramic transformer made from a piezoelectric ceramic material stacked in a multilayer package which has a driving section 502 formed by alternately stacking piezoelectric ceramic layers polarized in a direction of thickness of the piezoelectric plate. The driving section 502 has internal interdigitated electrode layers 504A, 504B for causing piezoelectric vibration by a driving voltage applied to an input terminal (Vin). A first driven section 506, also made from piezoelectric ceramic layers polarized in the longitudinal direction of the piezoelectric plate, for generating a first output voltage (Vout1) at a first output by the piezoelectric vibration transmitted from the driving section 502. A second driven section 510, made from piezoelectric ceramic layers polarized in the thickness direction of the piezoelectric plate, for generating a second output voltage (Vout2) at a second output by the piezoelectric vibration transmitted from the driving section 502.

Abstract: A piezoelectric transformer with voltage feedback is disclosed. The transformer comprises a piezoelectric plate of predetermined length, width and height with a driving section formed by alternately stacking a plurality of piezoelectric ceramic layers having internal interdigitated electrode layers. A driven section including an unpolarized dielectric section, a voltage feedback section in the form of a multilayer electrode structure or an outer strip, and a normally polarized dielectric section is also disclosed. The transformer generates an output voltage at an output terminal by the piezoelectric vibration transmitted from the driving section. A feedback control circuit is connected to the voltage feedback section. The isolated voltage feedback provides feedback control to keep the transformer operating at the proper resonant frequency even as there is a change in output load of the transformer.

Abstract: There is provided a piezoelectric transformer including (a) a cylindrical body made of piezoelectric material and longitudinally defining a driven section and a voltage generating section, the voltage generating section being polarized in one of directions in a direction of a longitudinal axis of the cylindrical body, (b) a pair of first electrodes formed at a curved surface of the cylindrical body in the driven section and defining a plurality of regions in the driven section in a direction of a longitudinal axis of the cylindrical body, the first electrodes being electrically isolated with each other, the regions being polarized so that every other regions are polarized in opposite directions in a direction of a longitudinal axis of the cylindrical body, the pair of first electrodes comprising a plurality of strip-shaped electrodes wound around the cylindrical body and disposed in parallel with one another in a direction of a longitudinal axis of the cylindrical body, every other strip-shaped electrodes bei

Abstract: A vibration gyroscope 10 includes a vibrator 12. The vibrator 12 has a vibration member 14 formed in a regular triangular prism shape and piezoelectric elements 16a, 16b and 16c. Two of the piezoelectric elements 16a and 16b are polarized in the direction from the outside to the vibration member 14, and the other piezoelectric element 16c is polarized in the direction from the vibration member 14 to the outside. An oscillation circuit 28 sends signals to the piezoelectric elements 16a to 16c and a signal output from the vibration member 14 is fed back. Two of the piezoelectric elements 16a and 16b are connected to a differential circuit 30. The differential circuit 30 is connected to a synchronous detection circuit 32 and then connected to a smoothing circuit 34 and a DC amplifier 36 in series.

Abstract: A piezoelectric transformer element is wrapped together with primary lead members and secondary lead members by a thin soft insulating sheet, with the primary and secondary lead members being exposed outside the wrapping sheet, so that the transformer element is small in size, and easy in handling, and mounting operation on a circuit board. The primary and secondary lead members can be formed of a flexible flat cable. In an electric power supply device using the piezoelectric transformer element, the transformer element, and the flexible flat cable are wrapped by the wrapping sheet together with a portion of a circuit board on which the transformer element and other circuit elements are mounted.

Abstract: The invention relates to a composite piezoelectric multilayer element of which, in operation, only a part is piezoelectrically active, and to a method of manufacturing such an element. In accordance with the invention, the piezoelectrically inactive part has larger dimensions in one or more directions than the part which, in operation, is piezoelectrically active when a voltage is applied across the electric connections of the element. Moreover, the inactive part is built up of ceramic foils and electrode layers whose thickness and composition correspond to the thickness and composition of the part of the element which, in operation, is piezoelectrically active. The element in accordance with the invention can be manufactured in a simple and inexpensive manner.

Abstract: A multi-layer piezoelectric transformer device includes first and second electroactive members having electrodes bonded to each of their opposing major faces; and a bonding layer disposed therebetween. The first and second electroactive members are polarized in a thickness direction, between their two major faces, such that when energized by an electric field the first and second electroactive members longitudinally strain. The first and second electroactive members are arranged such that deformation of one electroactive member results in corresponding deformation of the other electroactive member. The device provides substantial transformation ratios in which relatively high power may be transferred in relation to the size of the unit, operability over wide input and output frequency bandwidths, and electrical isolation of the voltage and current at the input to the device from the voltage and current at the output of the device.

Abstract: A piezoelectric transducer has groups of a first part and second part therebetween. Thin piezoelectric ceramic layers in groups and thick piezoelectric ceramic layers in the second part are polarized in the direction of thickness A or B. All of electrodes are layers, and each electrode is provided between the piezoelectric ceramic layers. A step-up output voltage is generated between the piezoelectric ceramic layers of the second part by longitudinal vibration of the piezoelectric ceramic layers of the groups.

Abstract: A ladder type filter achieves a substantial reduction in distortion in filtering characteristics. The ladder type filter includes a supporting substrate formed of an insulating material. Supporting members are attached to lands which are formed by portions of pattern electrodes disposed on the supporting substrate. A plurality of piezoelectric resonators are mounted on the supporting members and connected in a ladder arrangement to define a ladder type filter. Each piezoelectric resonator has a base member in which piezoelectric layers and internal electrodes are laminated. External electrodes formed on one side surface of the base member are connected to the internal electrodes disposed in the base member. The width w and the thickness t of the piezoelectric resonators and the number n of laminated layers each comprising one of the piezoelectric layers and one of the internal electrodes disposed adjacent to the corresponding piezoelectric layer are selected so as to satisfy 1.ltoreq.log.sub.10 (n.sup.2 wt).

Abstract: A generator section and a pair of drive sections are disposed along the lengthwise of a piezoelectric ceramic plate. The one pair of drive sections are disposed at both ends or at one end of the plate and have a pair of electrodes for each. The piezoelectric ceramic plate in the drive sections are polarized oppositely in direction and connected to a pair of external terminals. The generator section has two pairs of opposed electrodes which are polarized oppositely from the center along the lengthwise of the plate. The two pairs of opposed electrodes are respectively short-circuited and connected to external terminals. A voltage can be taken out from between the external terminals of the generator section at the vibration nodes when the piezoelectric ceramic plate in the drive section is vibrated by applying an AC voltage to between the input terminals on the drive section side at the resonance frequency of the fourth-order mode longitudinal vibration in lengthwise.

Abstract: A piezoelectric transformer using a piezoelectric annulus, divided into sections, includes at least one input and one output electrode configuration. The input electrodes are formed by covering top and bottom surfaces of the divided section of piezoelectric annulus. The low impedance portions, which are input regions, are poled parallel to the thickness direction and the high impedance portions, which are output regions, are poled tangentially. The transformer is operable at several radial mode resonance frequencies of piezoelectric ring. Two stepped up ac output voltages, in phase or 180 degree out of phase, can be obtained at several resonance frequencies of the piezoelectric annulus. The transformer is also operable as a step-down transformer by inverting the input and output ports.

Abstract: In a piezoelectric transformer, a piezoelectrically inactive region 11 is provided between a driving portion 22 and a power generating portion 31. The power generating portion 31 extends longitudinally of the piezoelectric body 1 and is provided with a pair of top and bottom electrodes 7T and 7B on its major surfaces. The driving portion 22 is provided with a side electrode 5 on a side surface perpendicular to the width direction. Other electrodes 50T and 50B are also provided so as to be parallel to the electrodes 7T and 7B. The power generating portion 31 is polarized in the width direction and the thickness direction of the piezoelectric body and the driving portion 22 is polarized in the width direction of the piezoelectric body 1. By regulating width of the piezoelectrically inactive region 11 provided between the electrode 50T (50B) of the driving portion 22 and the electrode 7T (7B) of the power generating portion 31, the transforming ratio can be regulated.

Abstract: A page wide piezoelectric ink jet print engine and a method of manufacturing the same. The page wide ink jet print engine includes lower and upper body parts, each formed from piezoelectric material and having a plurality of generally parallel, spaced projections. Lower side surfaces of the projections of the lower body part are conductively mounted to corresponding bottom side surfaces of the projections of the upper body part to define a plurality of generally parallel, axially extending ink-carrying channels from which ink may be ejected.

Abstract: A piezoelectric transformer comprising a rectangular plate of a piezoelectric material which is polarized in a thickness direction in a first half section of the plate in a longitudinal direction but is polarized in a width direction in a second half section of the remaining half section. A pair of primary electrodes are coated on the upper and the lower surfaces of the first half section and a pair of secondary electrodes are coated on the opposite side surfaces of the second half section, in an alternative structure, the plate is polarized in the thickness direction in opposite end sections of the plate having a size one third of length of the plate and polarized in width direction at the remaining middle section of plate between opposite end sections. The pair of primary electrodes formed on upper and lower surfaces of opposite end sections of plate and pair of secondary electrodes formed on opposite side surfaces of middle section.

Abstract: A piezoelectric ceramic transformer has a rectangular parallelopiped piezoelectric ceramic plate divided into a generator section and driving sections on both sides of the generator section, and first ring-shaped input electrodes and second ring-shaped input electrodes are alternately put on the rectangular parallelopiped piezoelectric ceramic plate at intervals so as to create electric field perfectly oriented in the longitudinal direction of the ceramic plate.

Abstract: A piezoelectric transformer has a driving section area which is provided with input electrodes at the central portion of a long-plate-shaped piezoelectric element and which is polarized in the direction of the thickness thereof; and power generating section areas which are provided with output electrodes on the ends surfaces in the direction of the length thereof, which are polarized in the opposite directions from each other with the driving section area between them, and which are disposed on both ends of the piezoelectric element. The piezoelectric transformer is excited in the half wavelength mode to obtain an output between the output electrodes and the input electrodes. A ratio L2/L1 of the length L2 of the driving section to the overall length L1 in the direction of the length of the piezoelectric transformer ranges from 0.3 to 0.6.

Abstract: In a piezoelectric transformer unit which transforms an input voltage into an output voltage and which includes a piezoelectric transformer element driven by high electric power, a package is provided to accommodate the piezoelectric transformer element therein. Electrodes are attached to nodes of the piezoelectric transformer element and supported by each pair of input and output conductive leads which are operable as leaf springs and which are extended through the package. Contact portions of the conductive leads may provide point contacts, area contacts, and/or line contacts.

Abstract: In a piezoelectric transformer comprising first and second driving blocks which are operable in a piezoelectric transverse vibration mode to induce a longitudinal vibration in a longitudinal direction and a voltage generating block formed between the first and the second driving blocks and which is operable in a piezoelectric longitudinal vibration mode in response to the longitudinal vibration, the voltage generating block comprises first and second voltage generating portions for generating an output voltage by the piezoelectric longitudinal vibration mode, a primary voltage producing portion formed between the first and the second voltage generating portions, and first and second secondary voltage producing portions formed at both sides of the voltage generating block. The first and the second driving blocks are supplied, in common, with an a.c. voltage through first and second input terminals.

Abstract: An ultrasonic motor with a stator uniformly made of a material that can convert electrical energy to mechanical energy. The stator includes a first part having two corresponding electrodes for applying a signal to the first part, and a second part, uniformly configured to the first part, having an area adjacent to the first part where the material does not exist. The second part does not exist between the electrodes. A moving element is in contact with the second part and driven by progressive oscillation waves generated in the second part due to the signal applied to the electrodes.

Abstract: A driving device for driving a discharge tube, wherein a pair of electrodes is formed on a piezoelectric transformer, and a voltage, which is periodically inverted, is applied to the electrodes. This design makes it possible to take out high voltage from the piezoelectric transformer due to the piezoelectric effect, ignite a discharge tube, and keep the discharge tube ON. Thus, a smaller and thinner driving device for a discharge tube can be achieved.

Abstract: Methods and compositions are described for the preparation of piezoelectric ceramic-polymer composites having improved properties for application in piezoelectric devices. These composites consist of piezoelectric particles embedded in a polymer matrix. The improvements of this invention result from discoveries of the effects of particle size, particle size dispersity, volumetric loading levels, ceramic dielectric constant, and polymer dielectric constant on performance. Various improved devices based on these compositions are also described.

Abstract: A piezoelectric transformer has a piezoelectric substrate having first and second main faces. The substrate has first and second primary-side regions and a secondary-side region in its longitudinal direction in this order. The first region has a length of a half wavelength of stress distribution at the time of resonance in the longitudinal direction and has either positive or negative stress. The second region has a length of a half wavelength or less of the stress distribution and has either positive or negative stress. First and second electrode are respectively disposed on the first and second main faces in the first primary-side region, and the substrate between the first and second electrodes is polarized in the thicknesswise direction. Third and fourth electrodes are respectively disposed on the first and second main faces in the second primary-side region, and the substrate between the third and fourth electrodes is polarized in the thicknesswise direction.

Abstract: In an electro-mechanical energy conversion device which is disclosed, green sheets on which whole surface electrodes for grounding have been printed and green sheets on which 2-divided electrodes have been printed are laminated. The green sheets having the 0.degree. phase and 90.degree. phase on which the 2-divided electrodes have been printed are laminated through the printed sheet on which the whole surface electrode for grounding. After the laminate body was sintered and integrated, it is polarized in a manner such that the polarizing directions in the thickness direction of each layer are opposite between the two divided electrodes which form one pair by using the whole surface electrodes for grounding and the 2-divided electrodes which were printed, thereby constructing the conversion device for the laminated type vibration driven motor.

Abstract: An ink droplet jet device having a piezoelectric ceramic plate is provided with ink chambers having partitions. The front half of each partition is opposite to the rear half in the direction of polarization. When a voltage is applied to the electrodes of a given partition, the front and the rear half thereof deform in the opposite directions because of their inverse directions of polarization. This prevents the introduction of air through the nozzles into the ink chambers adjacent to the activated ink chamber and the speed of printing is increased.

Abstract: One driver having external electrodes arranged over both surfaces of a piezoelectric ceramic plate polarized in the direction of its thickness, and one generator having two mutually opposed interdigital electrodes on one or both surfaces of a piezoelectric cermic plate and alternateley polarized in the direction of its length between the electrode fingers of the interdigital electrodes are formed combined in alignment in the direction of the length of the piezoelectric ceramic plate. Alternatively, the driver and generator may be formed in alignment in the direction of the width of piezoelectric ceramic plate. By applying a low voltage to this piezoelectric ceramic transformer from the driver at a resonance frequency of a longitudinal vibration of second order mode of the piezoelectric ceramic plate, a high voltage can be picked up from the generator.

Abstract: A co-fired laminate (10) for use in printheads for drop-on-demand ink jet printers has two inner layers (12, 14) of piezoelectric material which are thickness poled in opposite senses, two outer layers (11, 15) of inactive material and a fifth layer (13) disposed between the inner layers which is electrically insulating under the printhead operating conditions and conductive under the poling conditions of the inner layers. The fifth layer preferably is an N.T.C. material with its critical temperature between the operating and poling temperatures. After poling of the inner layers further manufacture of the printhead from one side thereof can be effected as described.

Abstract: A multilayer piezoelectric composite comprising a bonded laminate each layer of which is composed of a green sheet of a low-temperature sintering lead zirconate titanate piezoelectric ceramic. The temperature coefficient of a frequency constant of at least one layer has a polarity opposite to the polarity of those of the other layers. The bonded laminate is sintered at a temperature which does not produce any or almost any interdiffusion between layers so that the absolute value of the temperature coefficient of a frequency constant of the bonded laminate is smaller than the absolute value of the temperature coefficient of a frequency constant of any or one of the layers.

Abstract: A type of piezoelectric transformer (PT) which vibrates in length extensional mode is provided. The piezoelectric transformer (PT) has a piezoelectric substrate which has a first dimension, a second dimension and a third dimension with the first dimension being longest and the third dimension being shortest. The substrate has two polarization directions parallel to the first dimension near two terminals of the first dimension and at least two opposite polarization directions on a central portion of the substrate transversely to the first dimension. The substrate further has at least two electrodes on a portion horizontal to the first dimension. Comparing with traditional piezoelectric transformers, the new one can solve the polarization difficulties and reduce audio noise output without sacrificing the electrical properties or even have better voltage transformation characteristics.

Abstract: An acceleration sensor, which is particularly adapted for use in motor vehicles, is improved by structuring it to be readily testable, to assure reliability before installation. The acceleration sensor has a piezo element (1), which consists of at least two piezo-electric plates (2) placed on top of each other, the piezo-electrical polarization of which is oriented in opposite directions. At least two electrodes (9) are placed on each of the topside (7) and the underside (8) of the piezo element (1). For testing the sensor, the piezo element is deformed by the application of an electrical voltage to electrodes (9) of a first lateral portion (11a) of the piezo element. This deformation is detected by means of a deformation-generated voltage at the electrodes (9) of a second lateral portion (11b) of the piezo element.