Variable Patents (Class 361/277)
  • Patent number: 6229684
    Abstract: A variable capacitor having low loss and a correspondingly high Q is provided. In addition to a substrate, the variable capacitor includes at least one substrate electrode and a substrate capacitor plate that are disposed upon the substrate and formed of a low electrical resistance material, such as HTS material or a thick metal layer. The variable capacitor also includes a bimorph member extending outwardly from the substrate and over the at least one substrate electrode. The bimorph member includes first and second layers formed of materials having different coefficients of thermal expansion. The first and second layers of the bimorph member define at least one bimorph electrode and a bimorph capacitor plate such that the establishment of a voltage differential between the substrate electrode and the bimorph electrode moves the bimorph member relative to the substrate electrode, thereby altering the interelectrode spacing as well as the distance between the capacitor plates.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: May 8, 2001
    Assignee: JDS Uniphase Inc.
    Inventors: Allen Bruce Cowen, Vijayakumar Rudrappa Dhuler, Edward Arthur Hill, David Alan Koester, Ramaswamy Mahadevan
  • Patent number: 6226168
    Abstract: A variable capacitor includes a stator, a conductive rotor, and a spring-action portion. The rotor electrode projects from the rotor, and a protrusion extends from the rotor as far as the rotor electrode, wherein the protrusion is formed on the rotor in a region other than that where the rotor electrode is formed. The spring-action portion applies a spring force on the rotor so as to press the rotor against the stator. The spring-action portion is formed on a cover around an adjustment hole formed in the cover. The cover allows the rotor to rotate relative to the stator, and the adjustment hole permits the introduction of a tool for rotating the rotor by inserting the tool therethrough. The radial position of the protrusion is selected so as to substantially fall on a circular trajectory which, as the rotor rotates, is swept out on the rotor by a section of the spring-action portion, which section is in contact with the rotor.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: May 1, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Yasunobu Shibata
  • Patent number: 6212056
    Abstract: First and second wafers are micromachined by standard integrated-circuit fabrication techniques to respectively make first and second component parts of a variable capacitor. A thin flexible membrane in the first wafer is integral with and mechanically supported by the first wafer. A metal pattern on the first wafer includes a first capacitor plate on the membrane. In the second wafer, a well is formed. A metal pattern on the second wafer includes a second capacitor plate in the well. By bonding the two parts together face-to-face, the capacitor plates are positioned in spaced-apart alignment with each other. External electrical connections to the plates are made via bonding-pad portions of the metal patterns on the wafers. In response to electrical control signals, the metal plate on the membrane can be moved toward the other plate, thereby selectively changing the capacitance of the assembly.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: April 3, 2001
    Assignee: Lucent Technologies Inc.
    Inventors: Peter Ledel Gammel, James Albert Walker
  • Patent number: 6147855
    Abstract: A variable capacitor that provides a full range of capacitance, while reducing the amount of rotation necessary to effect maximum variation in capacitance, and while eliminating any wear-related deterioration in device performance includes at least two coplanar, electrically isolated sets of parallel electroconductive members so configured as to form a fixed set of capacitor plates, each of which may be separately electrically connected to an electrical circuit. A movable group having at least one member including at least one electroconductive area is positioned parallel to, and spaced from, the fixed set of plates. The movable group is adapted for rotation about an axis perpendicular to a surface plane of the first set of plates to vary an amount by which said movable group overlaps the surface of each of said capacitor plates, and thereby provide variable capacitive coupling between the two isolated electroconductive members that comprise the fixed set of capacitor plates.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: November 14, 2000
    Assignee: Applied Materials, Inc.
    Inventor: William N. Taylor, Jr.
  • Patent number: 6147856
    Abstract: Devices for use in highly integrated radio frequency transceivers utilize micro-electro-mechanical systems, or wobble motors, to form superior switches and to select and vary components that determine different frequencies of operation. Each device has a substrate with concentric rings of electrodes and contacts. A circular rotor is centrally pivoted or wobbled to engage the contacts along its circumferential edge. The rotor may be mechanically or materially modified to create symmetric or asymmetric forms which interact with one or more stationary capacitor electrodes on the substrate. The positioning of the rotor forms in terms of rotation, overlap and separation, relative to the capacitor electrodes, varies the capacitance.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: November 14, 2000
    Assignee: International Business Machine Corporation
    Inventor: John P. Karidis
  • Patent number: 6107808
    Abstract: A capacitor is made up of a housing; a first plurality of capacitors within the housing; a second plurality of capacitors within the housing; a first electrode coupled to a first terminal, with the first terminal being electrically contactable outside the housing; a second electrode coupled to a second terminal, with the second terminal being contactable outside the housing; a threshold circuit that compares performance of the first plurality of capacitors with performance of the second plurality of capacitors, detects an unbalance, and generates an output signal; and a signal output coupled to the threshold circuit, the signal output being accessible outside the housing. In another embodiment the capacitor has a housing; a first electrode contactable from outside the housing, a second electrode contactable from outside the housing, and an unbalance detection output contactable from outside the housing, wherein an unbalance detection signal indicative of a degree of unbalance.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: August 22, 2000
    Assignee: Maxwell Energy Products, Inc.
    Inventors: Gregg L. McKee, Frederick W. MacDougall
  • Patent number: 6101084
    Abstract: A signal is transferred without brushes between rotatable and non-rotatable components of a machine. An input signal is applied to one of the components. An axially symmetrical electromagnetic field is generated in response to the input signal. The electromagnetic field is detected by the other component and an output signal is generated in response to the detected electromagnetic field. A rotating transformer couples an information signal or power from an auxiliary generator to an external device for processing. The rotating transformer includes a rotor assembly and a stator assembly. The rotor assembly includes a pair of rotor plates. The stator assembly includes a pair of stator plates and a pair of dielectrics. A dielectric is mounted to a stator plate and mounted adjacent and spaced apart from a corresponding rotor plate to form a capacitor between the stator plate and the rotor plate.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: August 8, 2000
    Inventor: Mikhail A. Rakov
  • Patent number: 6097586
    Abstract: A variable capacitor includes a first electrode (2), a second electrode (3) and, located between the first and second electrodes, an array of gas discharge tubes (7). The capacitor includes means for producing an electrical discharge in the tubes, thereby affecting the capacitance of the capacitor.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: August 1, 2000
    Inventor: Carel Martin Grove
  • Patent number: 6064559
    Abstract: An optical position sensor for a vacuum tuning capacitor employs optic fibers that are positioned adjacent a nut associated with the guide shaft. A threaded lead screw is rotated to lift the nut and move the capacitor from a fully-withdrawn home position to a tuning position. A first fiber has its terminus aligned with the terminus of a second fiber to define a gap. A flag or shutter on the nut is positioned in the gap to block the light path between the fibers when the nut is in the home position, but is out of the gap to allow passage of light otherwise. This produces normally on signaling, giving the position sensor a fail-safe capability. The sensor can be incorporated into a cap or cover of the tuning capacitor.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: May 16, 2000
    Assignee: ENI Technologies Inc.
    Inventor: Richard E. Church, Jr.
  • Patent number: 6023406
    Abstract: An inductance/capacitance (LC) composite module with a built-in variable capacitor and coil is disclosed which includes a dielectric substrate having one principal surface on which a stator-side electrode is formed. Also formed thereon are a first terminal electrode connected to the stator-side electrode and a second terminal electrode independent of the first terminal electrode. The variable capacitor has a rotor of a chosen solid-state dielectric material in contact with the stator-side electrode. This rotor has thereon a rotor-side electrode which opposes the stator-side electrode with at least part of the rotor laid therebetween, thus forming an electrostatic capacitance. A rotatable support member is mounted so that it may rotate about the axis line at right angles to the substrate surface. The support member transmits its rotation to the rotor allowing the rotor to rotate with the support member.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: February 8, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Motohiro Kinoshita, Hiroyuki Kishishita
  • Patent number: 5982608
    Abstract: A variable capacitor in a semiconductor device is described in which the capacitance is varied by the movement of a dielectric material in the space between the plates of the capacitor in response to an external stimulus. A method of making such a variable capacitor is also described in which the capacitor is built in a layered structure with the top layer including a portion of dielectric material extending into the space between the capacitor plates. After formation of the top layer, an intermediate layer is etched away to render the top layer flexible to facilitate movement of the dielectric material in the space between the capacitor plates.
    Type: Grant
    Filed: January 13, 1998
    Date of Patent: November 9, 1999
    Assignee: STMicroelectronics, Inc.
    Inventors: Alexander Kalnitsky, Alan Kramer, Vito Fabbrizio, Giovanni Gozzini, Bhusian Guptz, Marco Sabatini
  • Patent number: 5914513
    Abstract: A tunable capacitor includes a first capacitor formed from semiconductor material and having a first terminal defining an anode, and a second capacitor integrally formed with the first capacitor from semiconductor material, the second capacitor being operatively coupled in series with the first capacitor, and having a second terminal defining a cathode. The second capacitor is formed as a field effect device or MOSFET configured to provide a depletion region controlled by applying a control voltage to a control terminal of the field effect device. The first capacitor is reverse biased by application of a reverse bias voltage between the anode and the cathode to provide a predetermined capacitance while the control voltage applied to the control terminal of the second capacitor varies the depletion region such that the capacitance of second capacitor is varied independently of the reverse bias voltage.
    Type: Grant
    Filed: May 18, 1998
    Date of Patent: June 22, 1999
    Assignee: The Board of Trustees of The University of Illinois
    Inventors: Krishna Shenai, Malay Trivedi
  • Patent number: 5900592
    Abstract: A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast inventories of stored nuclear material can be continuously monitored and inventoried of minimal cost.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: May 4, 1999
    Assignee: Lockheed Martin Energy Research Corp.
    Inventors: Carl W. Sohns, Robert N. Nodine, Steven Allen Wallace
  • Patent number: 5901031
    Abstract: A reference electrode is fixed on the bottom of a concave portion of a substrate. A movable electrode is provided so that its electrode face faces that of the reference electrode at an interval to form a capacitor by the movable and reference electrodes. A driving electrode for driving the movable electrode is fixed on the substrate at an interval from the movable electrode. The distance 2L between the driving and movable electrodes is twice the distance L between the movable and reference electrodes. An external bias voltage is applied between the driving and movable electrodes to deflect the movable electrode. This doubles the range of the displacement of the movable electrode, thereby increasing the capacity change rate of the variable capacitor.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: May 4, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tsutomu Ishige, Yasuhiro Negoro, Yuji Iyoda, Yasutaka Fujii, Katsuhiko Tanaka
  • Patent number: 5828542
    Abstract: The capacitance type gaseous sensing device (10) includes a first electrode layer (12) formed on a semiconductor substrate layer (14). A seed layer (16) is formed on the first electrode layer (12). A reorganized layer (18) is formed on the first electrode layer (12) through interaction with the seed layer (16) to form a porous sensing layer. A second electrode layer (20) is formed on the reorganized layer (18). The reorganized layer (18) absorbs gaseous elements that change the dielectric constant of the capacitance type sensor device (10). A change in the dielectric constant causes a change in the capacitance of the reorganized layer (18) as measured across the first electrode layer (12) and the second electrode layer (20).
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 27, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Scott J. Riley, Kenneth J. Balkus, Jr., Bruce E. Gnade
  • Patent number: 5818683
    Abstract: A small variable capacitor including a movable section composed of a movable electrode supported by a supporting section. A driving electrode and a detecting electrode are provided facing the movable electrode. When an external bias voltage is applied between the movable electrode and the driving electrode, Coulomb force is generated between them. Due to that, the movable section is attracted toward the driving electrode while keeping a balance between its own resilience force and the Coulomb force. At this time, part of the movable section facing the detecting element is displaced more than the other part of the movable section facing the driving electrode. Thereby, because an electrostatic capacity between the movable section and the detecting electrode is inversely proportional to the average distance, a large electrostatic capacity may be obtained and variability of the electrostatic capacity becomes large.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: October 6, 1998
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Yasutaka Fujii
  • Patent number: 5768089
    Abstract: A variable external capacitor produces greater functionality for NMR probes by reducing the size of components and efficiently arranging the components. The variable external capacity has a cavity that allows adjustment tools to be extended through the variable external capacitor to adjust additional components that may be stacked above the variable external capacitor. The cavity may be used to house reactance such as a fixed capacitor or inductor connected in parallel with the variable external capacitor. The variable external capacitor includes a polytetrafluoroethylene housing configured to minimize its size and reduce lead lengths of the NMR circuit. A silver deposit plate on the polytetrafluoroethylene housing constitutes a stationary capacitor plate. A drum disposed inside the cavity and movably spaced from the stationary capacitor plate functions as a movable capacitor plate. An anti-rotation rail supports the drum to prevent rotation.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: June 16, 1998
    Assignee: Varian Associates, Inc.
    Inventor: James Patrick Finnigan
  • Patent number: 5636099
    Abstract: A variable capacitor for a high frequency circuit of an electrical appliance includes a chip capacitor mounted on a multilayer circuit board and interdigital capacitors formed at inner layers of the circuit board. A wiring pattern for soldering the chip capacitor is connected with the interdigital capacitors via through holes formed in the circuit board. Capacitance select portions are cut so that the capacitance best-suited to the circuit is obtained. The through holes connected to the interdigital capacitors of the inner layer are selectively disconnected from the wiring pattern for soldering the chip capacitor, thereby obtaining a variable capacitor capable of absorbing fluctuations of the circuit for selecting the best-suited capacitance.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: June 3, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Sugawara, Fumikazu Harazono
  • Patent number: 5604658
    Abstract: In a multilayer metallisation/dielectric structure on a silicon substrate a trimmable capacitor is formed between two of the higher metallisation layers, with one layer being segmented and the individual segments connected by way of one or more vias and respective narrow links to one terminal of the capacitor. The narrow links are formed from titanium tungsten on the oxide isolated silicon substrate.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: February 18, 1997
    Assignee: Plessey Semiconductors Limited
    Inventor: David J. Pedder
  • Patent number: 5590015
    Abstract: The variable capacitor (1) is characterized by the fact that the safety end switches (6, 7) as well as a displacement detector (10) are integrated in the housing (1) or in an additional housing (5) provided at one of the front ends of the capacitor housing (1). Due to this construction, the entire device becomes more compact and more precise in operation.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: December 31, 1996
    Assignee: Comet Technik AG
    Inventors: Andrea V. Planta, Rolf Gerber
  • Patent number: 5557495
    Abstract: A variable capacitor and method of varying capacitance in which two pressurally engaged plates having electrically conductive patterns on facing surfaces are separated by a low friction polytetrafluoroethylene (Teflon.TM.) dielectric disk so that the plates may be rotated relative to one another to vary capacitance. Each of the facing surfaces of the plates include two spaced semicircular patterns, one that is electrically connected to the capacitor and one that is not, for maintaining the separation of the plates from the disk. The dielectric disk may be ten to twenty times thicker than the semicircular patterns.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: September 17, 1996
    Assignee: Harris Corporation
    Inventors: Donald K. Belcher, David C. Bailey
  • Patent number: 5520759
    Abstract: The present invention relates to a method for manufacture of ceramic parts used for protecting semiconductor devices such as IC, LSI, etc. against anomalous high voltages such as noise, pulse, static electricity, etc. and the object of the present invention is to provide ceramic parts capable of removing or restraining high-frequency noises on signal lines by reducing the impedance of the devices.In order to attain the above object, according to the present invention, a pulse voltage of 50 kV in maximum value which requires a time of 200 nanoseconds or less for reaching the maximum value from an initial value and a time of 1 microsecond or less for returning to the initial value through the maximum value and which has an energy of 0.5 joule or lower is applied at least once between the electrodes (2).
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: May 28, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Keiichi Noi, Iwao Ueno, Yoichi Ogoshi, Yasuo Wakahata
  • Patent number: 5414589
    Abstract: The present invention provides a capacitor having a changeable dielectric capacity which has advantages in changing the dielectric capacity and increasing the maximum dielectric capacity. The capacitor having a changeable dielectric capacity comprises ceramic main body part 1 in which a first and second internal electrodes 2a and 2b are formed. Four terminal electrodes 3 are formed apart on a face of the ceramic main body part 1. A common terminal electrode 4 is formed on the ceramic main body part 1 so that it connects with the internal electrodes 2a and 2b. To these terminal electrodes 3 and 4 are connected their respective lead wires 5 for wiring.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: May 9, 1995
    Assignee: Rohm Co., Ltd.
    Inventors: Koshi Amano, Satoru Yatake
  • Patent number: 5412327
    Abstract: A capactive sensor contains a bridge circuit (1,2,3,4) which is comprised of an electrode surface (21) and a reference electrode surface (24) with the electrode surfaces located on the opposite sides of a plate. The bridge circuit is constructed as a multi-layered printed circuit board. The feed areas (23) which are opposite the electrode areas (21, 24) on one or two inner layers serve as feed capacitors (1, 2) in the bridge circuit (1, 2, 3, 4).
    Type: Grant
    Filed: September 20, 1993
    Date of Patent: May 2, 1995
    Inventor: Michael Meinen
  • Patent number: 5339211
    Abstract: An electrical or electronic circuit having at least one variable capacitor device connected in parallel relationship in the circuit by at least a pair of electrodes. The improvement constitutes the capacitor device being in the form of a silicon dioxide film derived from the oxidation of a hydrogen silsequioxane resin. The silicon dioxide film is characterized by a non-linear substantially symmetrical jV curve which includes a threshold voltage at which the silicon dioxide film undergoes a reversible transition from insulating to conducting. The jV curve further includes a regime of negative differential resistance in which an increase in the voltage applied to the silicon dioxide film above the threshold voltage causes a decrease of the current.
    Type: Grant
    Filed: October 26, 1992
    Date of Patent: August 16, 1994
    Assignee: Dow Corning Corporation
    Inventors: Udo C. Pernisz, Keith W. Michael
  • Patent number: 5264983
    Abstract: A monolithic capacitor whose capacitance can be varied by removing part of an electrode. The capacitor may comprise an end termination, coupled to a plurality of internal electrodes which are disposed in a dielectric, and a top electrode which is disposed on one side of the dielectric. If a part of the top electrode is removed, the capacitance of the monolithic capacitor is changed, without an unacceptable change in "Q". The top electrode may be disposed so that a part of it may be removed with an energy beam device, such as a laser or a particle beam.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: November 23, 1993
    Assignee: Johanson Dielectrics, Inc.
    Inventor: John Petrinec
  • Patent number: 5229911
    Abstract: A variable electronic component in the nature of a trimmer capacitor has greatly increased voltage rating and capacitance range, while eliminating possible failure modes. An annular opening formed in a stationary electrode is surrounded by plastic dielectric material so as to receive in interference fit a circular sleeve of an opposing impedance varying electrode. By filling the air gap with plastic dielectric material, no air contributes to the effective dielectric, while at the same time, preventing shorting as a result of loose metallic particles which might be present.
    Type: Grant
    Filed: June 4, 1992
    Date of Patent: July 20, 1993
    Assignee: Voltronics Corporation
    Inventor: David Ditlya
  • Patent number: 5192871
    Abstract: A semiconductor device (10), comprising a semiconductor substrate (12) having a layer of semiconductor material (14) deposited, coated or grown epitaxially as a single crystal or polysilicon on the surface of the substrate. The layer of material is also a semiconductor material, having a higher resistivity than the substrate it is deposited on. A dielectric layer (16) of a metal oxide is formed on the high resistivity layer (14), which is then covered with an amorphous layer (18) of a metal oxide dielectric. Zirconium titanate may be used as a metal oxide dielectric layer. A metal electrode (20) is formed on the amorphous layer (18) to form a Metal Insulator Semiconductor device. In an alternative configuration, the amorphous layer (18) may instead be placed between the high resistivity layer (14) and the dielectric layer (16), or a second amorphous layer (22) may be added between the high resistivity layer and the dielectric layer.
    Type: Grant
    Filed: October 15, 1991
    Date of Patent: March 9, 1993
    Assignee: Motorola, Inc.
    Inventors: E. S. Ramakrishnan, Kenneth D. Cornett, Wei-Yean Howng
  • Patent number: 5162972
    Abstract: A liquid filled variable capacitor or PFL which provides variable frequen impedance, and pulse length without changing the capacitor or PFL hardware. The capacitor is constructed from two or more conducting surfaces. A dielectric fluid mixture separates the conductors. A fluid supply system furnishes the dielectric fluid mixture to the conductors and provides for varying of the dielectric constant of the fluid and thus the capacitor operating characteristics, by varying the mixture composition. The fluid supply system has a mixing tank connected to both a supply of high dielectric constant fluid and a supply of low dielectric constant fluid. The high dielectric constant fluid and low dielectric constant fluid are mixed proportionally to obtain a dielectric fluid having the desired dielectric constant. A pump conveys the dielectric fluid between the mixing tank and the conductors while a heat exchanger controls the temperature of the dielectric fluid.
    Type: Grant
    Filed: March 30, 1982
    Date of Patent: November 10, 1992
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Ronald J. Gripshover, David B. Fenneman
  • Patent number: 5117206
    Abstract: A variable capacitance circuit comprising a capacitor array, associated switching elements and transient impedance varying circuits. The capacitor array comprises a plurality of capacitor elements connected to a common node coupled to a crystal oscillator in a crystal oscillator portion and each capacitor element includes a connected switching element that controls activation of selected capacitor elements that are selectively placed in operation as load capacitance with the crystal oscillator to change and adjust its frequency. Further, circuits are provided in a temperature compensation portion to selectively control the activation of the switching elements based upon decoded compensating values provided in memory, such as based upon sensed oscillator temperature conditions.
    Type: Grant
    Filed: December 4, 1990
    Date of Patent: May 26, 1992
    Assignee: Seiko Epson Corporation
    Inventor: Yoichi Imamura
  • Patent number: 5084801
    Abstract: A variable capacitor comprises two conductive plates with a liquid crystal material having an anisotropic dielectric constant disposed therebetween. The conductive plates are treated with a surfactant to align the liquid crystal molecules in a predetermined direction at the interfaces between the conductive plates and the liquid crystal material. A low-frequency control voltage above a threshold voltage is applied across the conductive plates to orient the molecules of the liquid crystal material so that the molecular axis with the highest dielectric constant aligns parallel to the applied voltage. Upon removal of the control voltage, the liquid crystal molecules resume their original orientation. In this way, the dielectric constant of the variable capacitor is varied between two predetermined values, thus varying the capacitance of the variable capacitor between two discrete values proportional thereto. An alternative control provides continuous control over a range of capacitance values.
    Type: Grant
    Filed: February 19, 1991
    Date of Patent: January 28, 1992
    Assignee: General Electric Company
    Inventors: Sayed-Amr A. El-Hamamsy, Christopher P. Yakymyshyn
  • Patent number: 5075600
    Abstract: A variable capacitor includes a fixed conductive plate and a movable conductive plate with a dielectric disposed between them. A piezoelectric actuator is used to vary the distance between the conductive plates by moving the movable plate with respect to the fixed plate, with capacitance changing in inverse proportion to distance moved. In an electrodeless high intensity discharge lamp ballast, such a variable capacitor is situated in series with the excitation coil of the lamp. When a control voltage is applied to the piezoelectric actuator, the movable plate is moved from a starting position to a running position so as to maintain the ballast load in tune under both starting and running conditions, respectively, resulting in higher efficiency operation.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: December 24, 1991
    Assignee: General Electric Company
    Inventors: Sayed-Amr A. El-Hamamsy, Joseph C. Borowiec
  • Patent number: 5018047
    Abstract: A multilayer capacitor has a dielectric block with a marked position where the adjustable capacitance is to be placed. The capacitor has two end walls on which are first and second terminal electrodes. The electrodes have first and second narrow bands extending over marginal end portions of first and second side walls of the block. Two narrow spaced conductive stripes on the first side wall extend from the first band along lateral edges of the first side wall and terminate short of the second band to define a first rectangular U-shaped extension of the first terminal electrode on the first side wall. In the block are embedded spaced electrodes to determined the capacitance of the capacitor. A first stripe of conductive ink of any desired width can be applied to an uncovered area of the first wall to contact the U-shaped extension of the first terminal electrode to adjust capacitance of the capacitor.
    Type: Grant
    Filed: July 20, 1990
    Date of Patent: May 21, 1991
    Assignee: American Technical Ceramics Corporation
    Inventors: Victor Insetta, Richard V. Monsorno, Donald J. Davis, Jr., Stephen Beyel
  • Patent number: 4800527
    Abstract: A semiconductor memory device comprises: a charge holding capacitor formed on a semiconductor substrate; an insulating layer formed on the capacitor; and a transistor formed on a monocrystalline or substantially monocrystalline semiconductor layer, which is provided by forming, on the insulating layer, a hetero material of a nucleation density sufficiently higher than that of the insulating layer and of a size smaller enough to allow growth of a single nucleus of a semiconductor layer, followed by crystal growth around a single nucleus formed on the hetero material.
    Type: Grant
    Filed: October 23, 1987
    Date of Patent: January 24, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaharu Ozaki, Takao Yonehara
  • Patent number: 4675960
    Abstract: An electrically variable three terminal monomorphic piezoelectric capacitor is manufactured with thick or thin film hybrid microelectronic circuit technology. A first capacitor plate and a ridge, which substantially surrounds and extends above the first capacitor plate, are formed on the surface of a substrate. A monomorphic piezoelectric wafer having a control plate and a second capacitor plate on opposing surfaces is bonded to the upper surface of the ridge. During bonding, a force is applied at the center of the wafer which fixes a permanent bow in the wafer in the direction of the first capacitor plate. A four terminal monomorphic embodiment and three and four terminal bimorphic embodiments are also described.
    Type: Grant
    Filed: December 30, 1985
    Date of Patent: June 30, 1987
    Assignee: Motorola, Inc.
    Inventor: Robert J. Higgins, Jr.
  • Patent number: 4520375
    Abstract: A fluid jet ejector, such as is used in an inkjet printer head, is provided by a pair of spaced capacitor plates, one of which is a thin diaphragm, preferably of semiconductor material, such as silicon. The capacitor plates may be photolithographically developed. Impressing a time varying voltage on the capacitor causes the diaphragm to be set into mechanical motion. A reservoir containing fluid, such as ink, is contiguous the diaphragm and has a nozzle through which fluid exits responsive to diaphragm motion.
    Type: Grant
    Filed: May 13, 1983
    Date of Patent: May 28, 1985
    Assignee: Eaton Corporation
    Inventor: John W. Kroll
  • Patent number: 4470096
    Abstract: A thick film capacitor with more than two layers configured to enable trimming of the lower layers to increase the capacitance per area ratio while maintaining a linear trimmability of the capacitor's complete range.
    Type: Grant
    Filed: June 18, 1982
    Date of Patent: September 4, 1984
    Assignee: Motorola Inc.
    Inventor: Patrick W. Guertin
  • Patent number: 4466045
    Abstract: A monolithic ceramic capacitor has at least two main buried electrodes extending to opposite ends of the ceramic body. Two auxiliary electrodes of smaller dimensions are buried between the two main electrodes and extend to one or both sides of the body. Conductive terminations may be applied to the surfaces of the body so that the capacity measured between the opposite body ends is close to a desired nominal value. This is accomplished by choosing or not choosing to apply termination portions for connecting each auxiliary electrode to a main electrode.
    Type: Grant
    Filed: July 6, 1983
    Date of Patent: August 14, 1984
    Assignee: Sprague Electric Company
    Inventor: James H. Coleman
  • Patent number: 4450500
    Abstract: An electric capacitor of variable capacitance, including a dielectric body comprised of densely sintered ceramic material, including a hollow space extending longitudinally through the tubular ceramic body for containing dielectric liquid. First and second dielectric liquids of different dielectric constants and densities are contained in the hollow space, and an adjusting cylinder connected to the hollow space adjusts the height levels of the two dielectric liquids in the hollow space for adjusting the capacitance of the capacitor. The hollow space is either longitudinal channels through the tubular body or is a radial space between two concentric tubular bodies which together define the dielectric body. The metal layers of the capacitor plates are respectively on the inside and the outside of the dielectric body.
    Type: Grant
    Filed: May 26, 1983
    Date of Patent: May 22, 1984
    Assignee: Draloric Electronic GmbH
    Inventor: Werner Wollenschlager
  • Patent number: 4190876
    Abstract: A variable capacitor can be constructed so as to utilize two elongated metal strips serving as electrodes. Such strips are secured to one another so that at least a part of one is above at least a part of the other. The electrodes are insulated from one another and are disposed in a helical coil in which the turns are spaced from one another a sufficient extent to permit relative movement between the individual turns. In the disclosed capacitor a support or mounting collar is secured to the outermost turn and a movable actuator is secured to the innermost turn. Preferably at least one of the electrodes is sufficiently resilient so as to serve as a helical spring which will return the coil back to its initial configuration after at least one turn of the coil has been moved relative to an adjacent turn of the coil. A second collar may be located around the first and secured to the first by a flexible mounting structure such as a spring.
    Type: Grant
    Filed: February 3, 1978
    Date of Patent: February 26, 1980
    Assignee: City of Hope National Medical Center
    Inventor: Brian L. Tiep
  • Patent number: 4012700
    Abstract: A capacitive adjusting device for a quartz crystal oscillator utilizing one of the metallization provided on the quartz crystal as a common electrode for a plurality of capacitors, the second electrodes of which are provided as metallized strips on a portion of a ceramic base member forming part of the casing containing the quartz crystal.
    Type: Grant
    Filed: February 4, 1976
    Date of Patent: March 15, 1977
    Assignee: Ebauches S.A.
    Inventor: Rene Besson