Abstract: A piezoelectric device having a crystallized piezoelectric film between a lower and an upper electrode, wherein the crystal axis of the columnar crystal grain with the (001) orientation in the crystal forming the piezoelectric film is inclined by a predetermined angle relative to the normal direction of the lower electrode face, thereby improving the electric/mechanic converting function under low voltage conditions.

Abstract: In order to provide a piezoelectric transformer-driving circuit capable of obtaining a drive pulse signal having a high frequency resolution from a clock having a low frequency, carrying out voltage detection by using a low-cost configuration, and carrying out digital processing, a piezoelectric transformer-driving circuit in accordance with the present invention is configured so that an error voltage calculation circuit multiplies the difference data between the output data of an A/D converter and reference data supplied externally by a constant and outputs the result as error data, so that a frequency setting circuit sets the frequency of the drive pulse signal of the piezoelectric transformer as M-bit data depending on the error data, and so that a frequency division ratio distribution divider circuit divides a clock having a predetermined frequency to generate the drive pulse signal of the piezoelectric transformer, wherein the frequency division ratio of the frequency division ratio distribution divider

Abstract: A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece, device, substrate machine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required.

Abstract: This invention concerns a transducer comprising a layer of active material and a backing plate (110). The backing plate (110) has first and second major surfaces. A layer (111) of active material is affixed to the first surface. The transducer also includes a region adjacent to the second major surface into which region the backing plate (110) can be deflected. The region is substantially isolated from any external pressure incident on the layer of active material. Moreover, the backing plate (110) and/or layer of active material (111) is of a non-uniform thickness. Preferably, the backing plate (110) is thicker at a central region thereof than at an edge region thereof.

Abstract: A piezoelectric actuator includes a main driver electrode 4 and a sensor electrode 5. A feedback signal is generated from the sensor electrode 5 in order to eliminate a primary vibration mode due to a primary resonance frequency. The main driver electrode extends to a fixture portion of the actuator, the fixture portion being fitted into a support member 11. The extending portion of the main driver electrode eliminates the electromechanical coupling against a secondary vibration mode due to a second resonance frequency. Features of the piezoelectric actuator suppress the resonance phenomenon, thus improving the response characteristics of the actuator.

Abstract: A surface acoustic wave device is arranged such that surface acoustic wave energy is trapped substantially perpendicularly to the surface acoustic wave propagation direction. At least one interdigital transducer having a plurality of electrode fingers and first and second bus bar electrodes is located on a piezoelectric substrate on which a surface acoustic wave is excited, and has an anisotropy index &ggr; of less than about −1 in the propagation direction. The electrode fingers each have a film thickness of not less than about 0.04 &lgr; in which &lgr; is the wavelength of the surface acoustic wave. At least a portion of the first and second bus bar electrodes have a thickness that is larger than that of each electrode finger.

Abstract: A surface acoustic wave element includes a surface acoustic wave substrate, an interdigital transducer electrode provided on the surface acoustic wave substrate and a lead electrode provided on the surface acoustic wave substrate. The lead electrode is connected to the interdigital transducer electrode. The surface acoustic wave element further includes a bump electrode provided on a portion of the lead electrodes. The bump electrode includes a first electrode structure and a second electrode structure. The first electrode structure has a top surface and is arranged in contact with the lead electrode, and the second electrode structure covers a portion of the top surface of the first electrode structure such that the remaining portion of the top surface of the first electrode structure is exposed along an entire periphery of the top surface of the first electrode structure.

Abstract: A piezoelectric substrate is constituted by a piezoelectric material of an effective Poisson's ratio being less than 1/3. The substrate has a pair of opposite faces and the opposite faces are provide with a pair of vibrating electrodes in correspondence. The opposite faces of the piezoelectric substrate are rectangular respectively. The sum of the lengths Lc of the one faces in the opposite faces 1a, 1b and the length Wc of the other side of the same is limited within range 2.22 mm≦≦2.24 mm or 2.34 mm≦≦2.48 mm, said one faces being vertical each other. The areas Sc of the opposite faces are 1.22 mm2≦Sc≦1.26 mm2 or 1.35 mm2≦Sc≦1.538 mm2. Accordingly, though using the piezoelectric material of the effective Poisson's ratio being less than 1/3, vibration in the thickness extensional fundamental waves can be steadily utilized.

Abstract: The present invention provides a piezoelectric substrate for a surface acoustic wave device which has high electromechanical coupling coefficient and low SAW velocity, and a surface acoustic wave device using the same. The present invention applies a single crystal comprising belonging to a point group 32 and having Ca3Ga2Ge4O14 type crystal structure. The basic component of the single crystal is comprised of La, Sr, Ta, Ga and O and is represented by the chemical formula: La3−xSrxTa0.5+0.5xGa5.5−0.5xO14. The composition ratio of Sr is preferably in the range of 0 x≦0.15, and more preferably in the range of 0.07 x≦0.08. The present invention also provides a surface acoustic wave device using that in which an interdigital finger electrode is formed in one main surface of the aforementioned piezoelectric substrate.

Abstract: A transducer apparatus is disclosed having a spool member with a body portion and first and second elevated regions formed on the body portion. A PVDF film surrounds the spool member, the film including an inner surface facing the spool member and an outer surface opposite the inner surface. The film as surrounding the spool member has a predetermined frequency of resonance. Lateral ends of the film are secured together by a securing material. The securing material is such that the secured ends of the film will have substantially the same resonance frequency as a remainder of the film. The film includes a non-electrode area at a perimeter of the inner surface and an electrode material formed on a remainder of the inner surface. Upon securing the lateral edges of the film together, the securement is at overlapping non-electrode lateral edges of the film. The securing material may be any one of an adhesive in combination with screws or thermally deformable nails, adhesive alone, tape, or ultrasonic welding.

Abstract: A stator assembly of a rotary electric device is manufactured and assembled at reduced cost with an enhanced level of precision. A stator assembly of a rotary electric device comprising a yoke provided with a plurality of stationary magnetic poles and a yoke plate bonded to said yoke by means of synthetic resin in a mold to form an integral unit for enclosing a stator coil is assembled by bringing an alignment pin arranged on a jig for combining the yoke and the yoke plate into engagement with a corresponding alignment sections of the yoke and the yoke plate to put the yoke and the yoke plate together in order to produce a unitary stator assembly and a step of placing the unitary stator assembly of the yoke and the yoke plate in an injection metal mold with said alignment section fitted to an alignment pin arranged in the mold for mutual engagement and injecting synthetic resin into the mold to bond the yoke and the yoke plate together.

Abstract: A piezoelectric device (1) includes an at least locally thin-walled ceramic substrate (2) and at least one piezoelectric transducer (3) formed on the thin-walled region (2a) of the substrate. The transducer (3) is film-shaped and has a convex shape to protrude toward the substrate (2).

Abstract: A double-sided flexible circuit is used to provide interconnection to a piezoelectric ultrasonic transducer array. The ultrasonic crystal is covered with first and second electrode layers having an insulation gap provided therebetween. The flexible circuit material is then bonded to the first and second electrode layers so that one side of the double sided flexible circuit makes contact to one set of transducer electrodes and the other side of the flexible circuit makes contact to the second set of transducer electrodes. The ultrasonic transducer desirably includes a concave acoustic lens having an acoustic velocity greater than water.

Abstract: Solid state thermionic energy converter semiconductor diode implementation and method for conversion of thermal energy to electric energy, and electric energy to refrigeration. In embodiments of this invention a highly doped n* region can serve as an emitter region, from which carriers can be injected into a gap region. The gap region can be p-type, intrinsic, or moderately doped n-type. A hot ohmic contact is connected to the n*-type region. A cold ohmic contact serves as a collector and is connected to the other side of the gap region. The cold ohmic contact has a recombination region formed between the cold ohmic contact and the gap region and a blocking compensation layer that reduces the thermoelectric back flow component. The heated emitter relative to the collector generates an EMF which drives current through a series load. The inventive principle works for hole conductivity, as well as for electrons.

Abstract: An ultrasound receiver includes a hollow cylinder formed primarily from flexible piezoeelectric film, the hollow cylinder having an outer surface, an inner surface, a central axis and a height measured parallel to the central axis. A sensing electrode is formed from conductive material applied to the inner surface, while a grounded electrode is formed from conductive material applied to the outer surface. The hollow cylinder is supported by a support structure configured to allow progagation of vibration waves circumferentially around a major part of the hollow cylinder. The sensing electrode is formed as a strip extending in an extensional direction substantially parallel to the central axis along a major part of the height, the strip subtending at the central axis an angle of not more than 90°.

Abstract: Embodiments of the present invention are directed to rotational actuators or rotators that rotate an object in a worm-like manner. One rotator includes piezoelectric members that are controlled to expand and contract in a predetermined sequence to rotate a ring. The rotator includes first and second coupling members which are adjustable in length to move between a coupled position being coupled with the ring and a decoupled position being decoupled from the ring. A top advancing member is connected between the top coupling end of the first coupling member and the top coupling end of the second coupling member. A bottom advancing member is connected between the bottom coupling end of the first coupling member and the bottom coupling end of the second coupling member. The top and bottom advancing members are adjustable in length to produce relative movements between the top coupling ends and between the bottom coupling ends, respectively.

Abstract: An ultrasonic motor includes an oscillation drive circuit for generating an oscillation wave by self-excited oscillation of an oscillator bonded with a piezoelectric element, and a start/stop signal generating circuit for generating a signal for controlling the starting and stopping of the ultrasonic motor by bringing the oscillation drive circuit into an active state and a stop state, respectively. The oscillation drive circuit includes a power amplifier for amplifying an excitation signal, a capacitive circuit for adjusting a frequency of the excitation signal, and a switching circuit connected to a capacitive element of the capacitive circuit for short-circuiting terminals of the capacitive element based on an output signal of the start/stop signal generating circuit.

Abstract: A compact linear bi-directional motor is driven by one or more induced strain actuators, such as piezoelectric actuators, fabricated in its preferred embodiment using MEMS technology and incorporating a plurality of multi-clamps that alternately engage, forced by electrically energized auxiliary actuators, the rails or micro-ridges located on the base of the motor, on which they ride. This function is synchronized with energizing of the main actuator that alternately extends and contracts causing incremental motion of the multi-clamp assembly. An external load can be attached through a shaft to the multi-clamp assembly or the base.

Abstract: Device for accurate position control of a force-transmitting system comprising at least one solid-state piezo actuator (7), wherein the piezo actuator (7)comprises a metal block (11) which is positioned between end plates (12, 13) and in the direction of the force has at least one duct (14) into each of which a stacked piezo element (15) fits. The height of the block (11) is shorter than the length of the piezo elements (15) and the difference in height corresponds to the shortening of the piezo elements (15) under the maximum permissible axial load acting thereon, and wherein the piezo actuator (7) is incorporated transversely to the direction of force, without play, in such a way into an element of the force-transmitting system that only a force in the axial direction of the ducts (14) can be transmitted to the piezo elements (15).

Abstract: A piezoelectric device operable to excite a thickness extensional third harmonic vibration is provided, which can realize a high performance oscillator with an excellent thermal stability. The piezoelectric device includes a piezoelectric substrate. The piezoelectric substrate is formed from a piezoelectric material containing as major components Sr, Bi, Nb, and O. Vibration electrodes are formed on both of the surfaces of the piezoelectric substrate. The range lying between the vibration electrodes and defined by the overlapped vibration electrodes constitutes an energy trapping range. The value L/t is set to be less than 9, in which L represents the length of the longest secant extending between intersections on the periphery of the energy confining region and t represents the distance between the vibration electrodes.