Abstract: A capacitive actuator (P), especially for a piezoelectrically operated injection valve for an internal combustion engine, is short-circuited by a discharge switch (M) after an actuation, the controlling input of the discharge switch (M) being connected to the actuator (P) so that the discharge switch (M) in case of a failure of the external control, is automatically rendered conductive by the actuator voltage (UP) and the actuator (P) is therefore automatically discharged.
Type:
Grant
Filed:
August 15, 2000
Date of Patent:
December 25, 2001
Assignee:
Siemens Aktiengesellschaft
Inventors:
Christian Hoffmann, Hellmut Freudenberg, Hartmut Gerken, Martin Hecker, Richard Pirkl
Abstract: A piezoelectric/electrostrictive device is disclosed comprising a driving portion to be driven by a displacement of a piezoelectric/electrostrictive element, a movable portion to be operated by a drive of the driving portion, a fixing portion for holding the driving portion and the movable portion, the movable portion being coupled with the fixing portion via the driving portion, and a hole formed by inner walls of the driving portion, an inner wall of the movable portion, and an inner wall of the fixing portion.
Type:
Grant
Filed:
January 25, 2000
Date of Patent:
December 25, 2001
Assignee:
NGK Insulators, Ltd.
Inventors:
Yukihisa Takeuchi, Tsutomu Nanataki, Masato Komazawa, Koji Kimura
Abstract: A surface acoustic wave motor with high energy efficiency, which may efficiently execute recovery of energy of surface acoustic waves propagated to the ends of piezoelectric substrate and re-excitation by the recovered energy, includes a comb-shaped electrode having interdigital structure for generating surface acoustic waves and two unindirectional comb-shaped electrodes having interdigital structure for recovering and re-exciting surface acoustic wave energy arranged on a piezoekextric substrate, and a slider disposed between the comb-shaped electrode for generating surface acoustic waves and the unindirectional comb-shaped electrodes for recovering and re-exciting surface acoustic wave energy.
Abstract: A modification of the traditional unimorph flextensional actuator is provided by replacing the metal shim with an electrically conducting oxide. Comprised of lead zirconate titanate and zinc oxide that is co-sintered, the laminate composite obtains large axial displacements while maintaining moderate axial loads. The varistor properties of zinc oxide dictate that the conductance increases several orders of magnitude when a critical electric field is applied. The versatility of the processing over other actuator system facilitates miniaturization, while maintaining comparable performance characteristics. Functional gradients in the material properties are created in the green body by layering thin tape cast sheets. The unique PZT-zinc oxide composite not only controls the piezoelectric gradient, but permits control of the sintering kinetics leading to the processing of either flat or highly domed structures.
Type:
Grant
Filed:
April 30, 1999
Date of Patent:
December 11, 2001
Assignee:
The Trustees of Princeton University
Inventors:
James S. Vartuli, David L. Milius, Xiaoping Li, Wei H. Shih, Wan Y. Shih, Robert K. Prud'homme, Ilhan A. Aksay
Abstract: A piezoelectric actuator has a rotational moving member and a supporting member disposed opposite to the rotational moving member and having cantilever portions. Each of the cantilever portions of the supporting member has a fixed end and a free end opposite to the fixed end for contacting the rotational moving member when the supporting member is oscillated. A piezoelectric member is disposed on a respective one of the cantilevers of the supporting member. A power source supplies a voltage to each of the piezoelectric members to oscillate the supporting member in a vibration mode higher than a secondary mode of vibration so that the free ends of the cantilevers make sufficient contact with the rotational moving member to thereby rotate the rotational moving member.
Abstract: An interchangeable vessel having a substance therein where the vessel is constructed to be inserted into a larger apparatus so that the apparatus may use the substance therein, the interchangeable vessel comprising a tank formed of acoustically conductive material and a piezo electric film element affixed to the outer surface of the vessel where the piezo electric film element includes electrical contacts interconnected to an active signal electrode and a ground electrode that are formed as part of the piezo electric film level sensor where the contact pads are constructed to be electrically coupled with electronics contained within the apparatus for driving the piezo electric element.
Abstract: An interdigitated electrode ferroic transducer includes a film of ferroic material electrically polarized substantially in the plane of the film; and a set of interdigitated electrodes including at least two electrodes spaced from one another on the same side of the film and disposed at the termini of the polarization field.
Type:
Grant
Filed:
April 28, 1999
Date of Patent:
November 27, 2001
Assignee:
The Charles Stark Draper Laboratory, Inc.
Abstract: Provided is a piezoelectric/electrostrictive device comprising a driving portion to be driven by a displacement of a piezoelectric/electrostrictive element, a movable portion to be operated based on a drive of the driving portion, and a fixing portion for holding the driving portion and the movable portion, the fixing portion and the movable portions being coupled via the driving portion, and a hole being formed by an inner wall of the driving portion, inner wall of the movable portion, and inner walls of the fixing portion.
Type:
Grant
Filed:
December 28, 1999
Date of Patent:
November 27, 2001
Assignee:
NGK Insulators, Ltd.
Inventors:
Yukihisa Takeuchi, Tsutomu Nanataki, Masato Komazawa, Koji Kimura
Abstract: An actuator driving circuit includes a drive pulse signal generator, a drive voltage generator for generating a drive voltage for drive pulse signal generation upon receipt of a power supplied from a power source. The drive pulse signal is generated so that the relationship between the frequency of power noise cyclically produced from the drive voltage generator and imposed on the drive voltage and the frequency of the drive pulse signal satisfies the following equation:
4000<|m·f1−n·f2|
wherein
m: positive integer below a specified value;
n: positive integer below a specified value;
f1:frequency of power noise; and
f2:frequency of the drive pulse signal.
Abstract: The surface acoustic wave device of the invention comprises a piezoelectric substrate made up of 64° rotated Y-cut lithium niobate (64LN) or 36° rotated Y-cut lithium tantalate (36LT) and an interdigital electrode formed thereon. The interdigital electrode comprises a titanium buffer metal film and an aluminum film formed thereon. On the 64LN substrate, both the titanium buffer metal film and the aluminum film are converted into a single-crystal film that manifests itself in a spot form alone upon selected-area electron diffraction. By forming the aluminum film on the 36LT substrate with the titanium buffer metal film located therebetween, it is possible to obtain a high-orientation, polycrystalline aluminum film oriented in the (111) direction. The aluminum film is made up of a single-crystal film or a high-orientation polycrystalline film oriented in the (111) direction, whereby migration of aluminum atoms is inhibited, resulting in a power-durability improvement.
Type:
Grant
Filed:
May 24, 1999
Date of Patent:
November 13, 2001
Assignee:
TDK Corporation
Inventors:
Noritoshi Kimura, Masahiro Nakano, Katsuo Sato
Abstract: In the operation of piezoactuators of multilayer construction, during the polarizing or during the operation of the piezoactuator tears can arise, due to voltages, in the metallization strips that are attached to the actuator on the outside for contacting the electrode layers. It is inventively proposed to install electrically conductive contact lugs directly at the stack or on the metallization strips such that a laterally protruding region remains, so that, even given arising tears, these nevertheless extend in the protruding region of the contact lug, and the tears are electrically bridged. Electrical terminal elements are provided so as the project above or laterally at the contact lugs.
Type:
Grant
Filed:
July 15, 1999
Date of Patent:
November 13, 2001
Assignee:
Siemens Aktiengesellschaft
Inventors:
Carsten Schuh, Clemens Scherer, Wilhelm Hekele, Christoph Hamann
Abstract: A piezoelectric element has a first and a second stack containing a plurality of piezoelectric ceramic layers and has an intermediate layer disposed between the first and the second stacks. The intermediate layer is formed as a supporting body made of a fiber composite material or glass. Such a multimorphous piezoelectric element exhibits a high efficiency and a high mechanical stability and, in addition, can be operated with low voltages.
Abstract: A lithography chuck (100) holds a flat object (150), such as a semiconductor wafer (150) at the backside (152). The chuck has, supported on a base plate (105), a plurality of pins (110-n) to receive partial forces (Fn) from the backside (152) and a plurality of piezoelectric elements (120-n) attached to the pins to sense the partial forces (Fn) applied from the object (150) to the pins (110-n). The piezoelectric elements (120-n) apply partial displacements (Bn) of the pins (110-n) to act on selected areas of the object (150) and thereby compensate for irregularities in the backside contour.
Type:
Grant
Filed:
April 10, 2000
Date of Patent:
November 6, 2001
Assignee:
Motorola, Inc.
Inventors:
John Maltabes, Alain Charles, Karl Mautz
Abstract: The invention utilizes multiple frequency sound in liquids to improve the cleaning or processing effect. The sound frequencies are produced in two or more non-overlapping continuous frequency ranges. The sound frequencies are controlled to change frequency within the frequency ranges and the sound frequencies are programmed by a digital code to jump amongst the frequency ranges. The sound frequencies may change continuously within the frequency ranges, and the sound frequencies may jump discontinuously from one frequency range to another. The frequency ranges may also be within different, non-contiguous and non-overlapping frequency bands.
Abstract: A piezoelectric motor including a motor body, a compliant layer in communication with the motor body, and a predetermined number of legs in communication with the compliant layer, which urges the legs into engagement with a substrate. Each of the legs includes a piezoelectric wafer, preferably operated in the shear mode. The actuation of a piezoelectric wafer causes the corresponding leg to be displaced relative to a substrate. This displacement results in the transfer of strain energy to the compliant layer. The energy stored in the compliant layer may be released, causing the motor to advance along the substrate. The legs may be capable of moving independently from one another and also may be capable of moving sequentially or in a predetermined groups or units. The legs also may be arranged in pairs with the leg pairs being capable of simultaneous actuation. The motor is capable of maintaining a high holding force in the absence of a power input.
Type:
Grant
Filed:
July 8, 1997
Date of Patent:
November 6, 2001
Inventors:
John Cunningham, Ephrahim Garcia, David V. Newton
Abstract: Modified configurations for electrical connectors to ceramic transducers are designed to reduce failure rates due to fatigue during transducer operation. These modifications eliminate or reduce one or both of the problems causing the fatigue, tensile forces acting on electrical wires connected to ceramic electrodes and unreliable solder joints. Star and pin configurations of wire soldered to ceramic transducers control the position of the wires, thus reducing the tensile forces on the wire. Plug connectors use pressure contacts between the ceramics, eliminating the need for solder joints.
Type:
Grant
Filed:
May 3, 2000
Date of Patent:
October 30, 2001
Assignee:
BAE Systems Aerospace Inc.
Inventors:
James A. Culbert, William H. Dexter, II, Warren J. Dickie, Edward Guida, Anthony Longabard
Abstract: The present invention relates to transducer packages which utilize lenses made of unpoled piezoelectric material or machined metal coupled to an impedance matched backing. The new transducer packages have minimal reverberation which allow for nearer standoff measurements, improved bond measurements, the ability to detect of thinner cement layers behind casing, and provide for better estimations of formation surface texture.
Type:
Grant
Filed:
July 14, 1999
Date of Patent:
October 30, 2001
Assignee:
Halliburton Energy Services, Inc.
Inventors:
James R. Birchak, Alvin B. Miller, James W. Stroud
Abstract: A surface acoustic wave device that is small, lightweight and highly reliable, and protects its functional portion. The surface acoustic wave device has surface acoustic wave elements mounted on a circuit substrate. Each surface acoustic wave element includes a frame-like first insulating film furnished to surround functional portions on a chip, and a lid-like second insulating film deposited on the first insulating film so as to cover driving electrodes and surface wave propagation paths of the functional portions, while securing a hollow portion over the functional portions.
Abstract: A turboexpander associated with a rotary compressor by means of a rotor shaft connecting the two. A bearing housing includes magnetic radial and thrust bearings which control the placement and dynamics of the shaft within the housing. A control passageway extends from the inlet of the compressor to the gas cavity behind the compressor rotor. This passage is controlled by a valve and in turn by the magnetic bearing controller to augment the operation of the active magnetic thrust bearings.
Abstract: The SAW component has electrical structures which are encapsulated and sealed against environmental influences by a cap cover. Connecting pads of the electrical structures are exposed in a window of the cap cover and the pads are provided with a metallization. Solderable metallized areas are formed on the cap cover, and they are connected to the pad metallizations via through-plated holes.
Type:
Grant
Filed:
June 22, 1998
Date of Patent:
October 30, 2001
Assignee:
Siemens Aktiengesellschaft
Inventors:
Wolfgang Pahl, Alois Stelzl, Hans Krüger