Tuning Fork Patents (Class 73/504.16)
  • Patent number: 7673512
    Abstract: An angular velocity sensor includes a base portion, three arm portions that extend as one piece from the base portion to an approximately same direction, a piezoelectric film formed on one surface of each of the arm portions, drive electrodes for excitation formed on the piezoelectric films of at least two outer arm portions, and detection electrodes for angular velocity detection formed on the piezoelectric film of at least a center arm portion. Among the three arm portions, the two outer arm portions are excited in phase, and the center arm portion is excited in opposite phase with the two outer arm portions. The drive electrodes excite the arm portions in a first direction vertical to surfaces on which the piezoelectric films are formed. The detection electrodes detect a vibration in a second direction parallel to the surfaces on which the piezoelectric films of the arm portions are formed.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: March 9, 2010
    Assignee: Sony Corporation
    Inventors: Kazuo Takahashi, Junichi Honda, Teruo Inaguma
  • Patent number: 7673511
    Abstract: A vibration gyro having a high accuracy, no vibration leak, and high S/N. The width of a detection leg of a resonator used in the vibration gyro is less than ? of the width of drive legs. The length of the detection leg is larger than the length of the drive legs. As a result, the distance between the detection electrodes is decreased by comparison with the conventional vibration gyro and, therefore, the detection signal is increased and S/N is raised. Furthermore, increasing the leg length brings the natural vibration frequency of out-of-plane vibration of the drive legs close to the natural vibration frequency of the detection leg, providing good coupling and reducing vibration leak to the support section. As a result, Q is increased and S/N is accordingly further increased.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: March 9, 2010
    Assignee: Citizen Holdings Co., Ltd.
    Inventor: Izumi Yamamoto
  • Patent number: 7673529
    Abstract: A method for processing a detection signal of a vibratory inertial force sensor is disclosed. This method improves detection accuracy of the vibratory inertial force sensor. A detection circuit of the vibratory inertial force sensor removes harmonic component from signals synchronously wave-detected, and amplifies the resultant signals, and then smoothes the amplified signals. A vibratory inertial force sensor adopting this method is also disclosed.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: March 9, 2010
    Assignee: Panasonic Corporation
    Inventor: Takeshi Uemura
  • Publication number: 20100050768
    Abstract: A tuning fork-type piezoelectric vibrator includes a substantially rectangular plate-shaped base to be supported by a circuit substrate and two pillar-shaped legs. The base includes a substantially rectangular plate-shaped junction arranged to be connected to the circuit substrate, and a body disposed between the junction and the two legs. In order for the difference between the resonant frequency in the drive mode of the tuning fork-type piezoelectric vibrator and the resonant frequency in in-plane, in-phase mode thereof to be at least about 1 kHz, the base and two legs are configured so that the product of the length of the body divided by the substantial width of the body minus the width of the legs and the resonant frequency in drive mode is at least about 60×103.
    Type: Application
    Filed: August 12, 2009
    Publication date: March 4, 2010
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Koji TAKEYAMA
  • Publication number: 20100050769
    Abstract: An angular velocity sensor includes vibrators, an internal circuit that drives the vibrators to detect an angular velocity signal, a circuit substrate on which components such as an IC and a passive component defining the internal circuit are disposed, and electrically connects the vibrators and the components, and a cap that covers a surface of the circuit substrate and encloses the vibrators and internal circuit. An output signal processed by the internal circuit is output from an external electrode provided on the back surface of the circuit substrate. Vibrator inspection electrodes are provided on the back surface of the circuit substrate, and the vibrator inspection electrodes are electrically connected to surface electrodes of the vibrators. Thus, electrical characteristics of the vibrators can be directly measured after assembly.
    Type: Application
    Filed: August 12, 2009
    Publication date: March 4, 2010
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Kosuke Watanabe, Keiichi Okano
  • Publication number: 20100043548
    Abstract: An angular velocity sensor includes a drive electrode section (26) for inputting a drive signal for driving a detecting element (21), a monitor electrode section (28) detecting the drive status of the detecting element (21) and outputting a monitor signal, and a sensing electrode section (27) outputting a sensing signal, which is generated due to an angular velocity given to the detecting element (21). The drive electrode section (26), the monitor electrode section (28), and the sensing electrode section (27) each have a lower electrode formed on a substrate, a piezoelectric film formed of a piezoelectric material on the lower electrode, and an upper electrode formed on the piezoelectric film.
    Type: Application
    Filed: December 11, 2007
    Publication date: February 25, 2010
    Applicant: PANASONIC CORPORATION
    Inventor: Youhei Ashimori
  • Publication number: 20100043547
    Abstract: An electronic component is disclosed, and this component includes an element with an electrode section which is formed of upper electrode (74), lower electrode (72), piezoelectric unit (70) placed between upper electrode (74) and lower electrode (72), and adhesive layer (76) layered between upper electrode (74) and piezoelectric unit (70). Piezoelectric unit (70) includes piezoelectric layer (80) made of piezoelectric material containing lead, and adhesive layer (76) includes a tungsten layer made of tungsten-based material. Piezoelectric layer (80) and the tungsten layer are layered together. The structure discussed above allows preventing a piezoelectric constant from lowering and a base-point voltage from varying. The lowering and the varying have been caused by a temperature-rise.
    Type: Application
    Filed: November 12, 2007
    Publication date: February 25, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Shoji Okamoto, Masahiro Yasumi, Yuuki Nakamura, Satoshi Ohuchi, Michihiko Hayashi
  • Publication number: 20100037692
    Abstract: Monolithic solid-state inertial sensor. The sensor detects rotation rate about three orthogonal axes and includes a micromachined monolithic piezoelectric crystalline structure including an equal number of vibratory drive and detection tines on each side of an axis of symmetry of the sensor, the tines being synchronized to have alternate actuation movements inward and outward.
    Type: Application
    Filed: February 4, 2009
    Publication date: February 18, 2010
    Inventors: Gaston Dube, Alfredo Riviere
  • Publication number: 20100011859
    Abstract: An angular velocity sensor detects an angular velocity of an object. The angular velocity sensor includes a detecting element, and a driving unit. The detecting element includes a supporting part, a first arm extending from the supporting part and being adapted to be fixed to the object, a second arm extending from the supporting part, and a first weight connected with the second arm. The second arm has substantially a U-shape and includes a first extending part extending from the supporting part, a first facing part facing the first extending part and extending in parallel with the first extending part, and a first joint part joining the first extending part to the first facing part. The first weight is connected with the facing part of the second arm. The driving unit includes first to fourth drivers. The first driver is provided at the first extending part and extends and contracts the first extending part.
    Type: Application
    Filed: September 19, 2007
    Publication date: January 21, 2010
    Applicant: PANASONIC CORPORATION
    Inventor: Jirou Terada
  • Publication number: 20100000322
    Abstract: Disclosed is an angular velocity sensor. The angular velocity sensor includes a first layer, a piezoelectric layer, and a second layer. The first layer has a first main surface and a second main surface, and includes a vibrator portion and a base portion that supports the vibrator portion. The piezoelectric layer is formed on the first main surface of the first layer. The second layer is integrally bonded to the base portion on a side of the second main surface of the first layer.
    Type: Application
    Filed: June 25, 2009
    Publication date: January 7, 2010
    Applicant: SONY CORPORATION
    Inventors: Junichi Honda, Teruo Inaguma, Tetsuya Shibayama
  • Publication number: 20090320594
    Abstract: An inertia force sensor includes a detection element having two orthogonal arms each formed by connecting one first arm orthogonally to two second arms; a support portion for supporting the two first arms; and two fixing arms connected at one end thereof to the support portion and fixed at the other end thereof to a mounting substrate. The second arms include opposing portions formed by bending the second arms to face the main portions thereof. The second arms are connected at their ends to weight parts, which include recesses to which the ends of the second arms are connected.
    Type: Application
    Filed: August 20, 2007
    Publication date: December 31, 2009
    Applicant: PANASONIC CORPORATION
    Inventors: Satoshi Ohuchi, Hiroyuki Aizawa
  • Patent number: 7637159
    Abstract: An inclination of an inclined surface formed by working a ridge of a resonator is set to be within a predetermined angular range, whereby a leakage of vibration in the out-of-plane direction is reduced, the leakage of vibration being generated according to the detuning degree adjustment. In addition, a single laser beam is irradiated onto the ridge at an incident angle within a predetermined angular range, whereby a simple working on the inclined surface is established for the leakage vibration adjustment. A degree of the leakage vibration of the resonator is determined based on a relationship with the drift amount that is a ratio of the angular velocity change, and the inclination of the inclined surface is set to be within a predetermined angular range, thereby suppressing the drift amount.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: December 29, 2009
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Izumi Yamamoto, Takashi Moriya, Tomoo Ikeda, Atsushi Murakami, Akihiro Shioji
  • Publication number: 20090314084
    Abstract: A vibrating gyroscope includes two input buffers each arranged to input voltage signals appearing at respective detection electrodes of one of two piezoelectric vibrators. An adding circuit adds up output voltages of the respective input buffers. An amplitude control circuit automatically controls a loop gain such that an output voltage of the adding circuit has a substantially constant amplitude. A phase-shift circuit controls the phase of a drive voltage supplied to the piezoelectric vibrators such that the piezoelectric vibrators oscillate by positive feedback. Two differential amplifier circuits each amplify a voltage difference corresponding to an angular velocity about an axis. Two synchronous detection circuits each perform detection using a synchronizing signal generated from an oscillation signal, and detect a voltage signal corresponding to the angular velocity.
    Type: Application
    Filed: June 8, 2009
    Publication date: December 24, 2009
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Hideaki SUGIBAYASHI, Keiichi OKANO
  • Patent number: 7624494
    Abstract: An inertial sensor includes a mesoscaled disc resonator comprised of micro-machined substantially thermally non-conductive wafer with low coefficient of thermal expansion for sensing substantially in-plane vibration, a rigid support coupled to the resonator at a central mounting point of the resonator, at least one excitation electrode within an interior of the resonator to excite internal in-plane vibration of the resonator, and at least one sensing electrode within the interior of the resonator for sensing the internal in-plane vibration of the resonator. The inertial sensor is fabricated by etching a baseplate, bonding the substantially thermally non-conductive wafer to the etched baseplate, through-etching the wafer using deep reactive ion etching to form the resonator, depositing a thin conductive film on the through-etched wafer.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: December 1, 2009
    Assignees: California Institute of Technology, The Boeing Company
    Inventors: A. Dorian Challoner, Kirill V. Shcheglov
  • Publication number: 20090288486
    Abstract: A vibration body 1 includes a vibrator 2 having vibration pieces 7 and a supporting part 5, and a mounting substrate 11 for mounting the vibrator. The mounting substrate has a seat part 13 for supporting the supporting part, and a base part 12. The seat part 13 has a level difference above the base part, the level difference being at least equal to or higher than the oscillation width of the vibration pieces, and the seat part is also provided with an edge portion 14 having a curved line shape. A normal line direction at each position on the edge portion is the same as a reference direction determined for the mounting substrate, or has at least one different angle with respect to the reference direction. When the vibrator is mounted on the seat part 13, tangential directions at the end portion of the supporting part and the edge portion of the seat part coincide with each other at a mounting position selected from the edge portion having the curved line shape of the seat part.
    Type: Application
    Filed: January 11, 2007
    Publication date: November 26, 2009
    Applicant: CITIZEN HOLDINGS CO., LTD.
    Inventors: Isao Arai, Yoichi Nagata
  • Publication number: 20090288487
    Abstract: An angular velocity sensor includes a vibrator vibrating, first and second differential circuits for outputting first and second difference signals, respectively, and a synchronous detector circuit for synchronously detecting the first and second difference signals. First and second sensors outputs first and second detection signals in response to a distortion produced due to an inertial force. The second detection signal has a phase reverse to a phase of the first detection signal. The first difference signal corresponds to a difference provided by subtracting the first detection signal from the second detection signal. The second difference signal corresponds to a difference provided by subtracting the second detection signal from the first detection signal. This angular velocity sensor detects an angular velocity of the vibrator accurately.
    Type: Application
    Filed: December 22, 2006
    Publication date: November 26, 2009
    Applicant: PANASONIC CORPORATION
    Inventor: Takeshi Uemura
  • Patent number: 7617727
    Abstract: A vibrating inertial rate sensor has operational elements that define axes that are rotationally offset or “skewed” from a node or anti-node reference axis. The skew may be relative to separate node or anti-node reference axes, or take the form of an element that is “split” about the same node axis. Both the drive signal and the sense signal may be resolved from a common set of sensing elements. The drive elements may also operate on a skewed axis angle to rotationally offset the vibration pattern to affect active torquing of the gyroscope. Skewed drive elements may be combined with skewed or split elements on the same device. The skewed sensing scheme may be applied to vibratory systems having one or more node axes. The skewed drive scheme may be applied to vibratory systems having two or more node axes to affect active torquing.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: November 17, 2009
    Assignee: Watson Industries, Inc.
    Inventor: William S. Watson
  • Patent number: 7617728
    Abstract: A gyroscope for detecting rotation about a gyro input axis, having a support structure, at least one mass flexibly coupled to the support structure such that it is capable of motion in two directions along a drive axis, the mass offset from the gyro output axis, one or more drives for oscillating the flexibly-coupled masses along the drive axis, one or more mass motion sensors that sense motion of the flexibly-coupled masses along their drive axes, and one or more gyro output sensors that detect rotation of the support structure about the output axis.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: November 17, 2009
    Inventor: Donato Cardarelli
  • Publication number: 20090272189
    Abstract: A method of operating an anti-phase six degree-of-freedom tuning fork gyroscope system comprises the steps of driving a first three degree-of-freedom gyroscope subsystem, and driving a second three degree-of freedom gyroscope subsystem in an anti-phase mode with the first gyroscope subsystem at an anti-phase resonant frequency. Acceleration or an angular rate of motion is sensed by means of the first and second three degree-of-freedom gyroscope subsystems operating in a flat frequency response range where the anti-phase resonant frequency is designed. Response gain and phase are stable and environmental and fabrication perturbations are avoided by such operation. A anti-phase six degree-of-freedom tuning fork gyroscope system which operates as described is also characterized.
    Type: Application
    Filed: January 25, 2006
    Publication date: November 5, 2009
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Cenk Acar, Andrei Shkel, Adam R. Schofield, Lynn E. Costlow, Asad M. Madni
  • Publication number: 20090255338
    Abstract: An acceleration sensing device includes: an outer frame; a first drive arm having both ends supported by sides of the outer frame through respective base parts, the sides opposing each other; a second drive arm extending from one of the base parts of at least one of the sides toward the other side; and a sensing arm that is disposed midway between the first drive arm and the second drive arm and extends form the one base part of the one side toward the other side, the sensing arm having an electrode in order to extract electric charge generated in the sensing arm. In the device, the first drive arm and the second drive arm have excitation electrodes for a flexural vibration and form a tuning fork type resonator, and center positions in thicknesses of sections that are located in the base parts and on an extension line of the first drive arm differ from a center position in a thickness of the first drive arm.
    Type: Application
    Filed: April 1, 2009
    Publication date: October 15, 2009
    Applicant: EPSON TOYOCOM CORPORATION
    Inventor: Jun Watanabe
  • Patent number: 7584661
    Abstract: A tuning fork gyro sensor includes a tuning fork vibrator and a casing. The tuning fork vibrator includes a pair of arms that extend parallel, a base that supports the pair of arms, and supporting members that are arranged on both faces of the base such that the supporting members are positioned at the equal distances from both the pair of arms, and that project from the both faces of the base, the both faces being perpendicular to both a direction in which the pair of arms extend and a direction in which the pair of arms are aligned. The casing is hollow to house and support the tuning fork vibrator by supporting the supporting members.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: September 8, 2009
    Assignee: Fujitsu Limited
    Inventor: Shigeo Matsunuma
  • Publication number: 20090165557
    Abstract: An angular velocity sensor includes a substrate having an upper surface having a first recess provided therein, an electronic component mounted in the first recess, and a vibration element mounted onto the upper surface of the substrate. The first vibration element has a portion located directly above the electronic component. This angular velocity sensor has a small size.
    Type: Application
    Filed: March 7, 2007
    Publication date: July 2, 2009
    Inventors: Shinjiro Ueda, Hiroaki Mouri, Koichiro Nakashima
  • Publication number: 20090145224
    Abstract: A method for processing a detection signal of a vibratory inertial force sensor is disclosed. This method improves detection accuracy of the vibratory inertial force sensor. A detection circuit of the vibratory inertial force sensor removes harmonic component from signals synchronously wave-detected, and amplifies the resultant signals, and then smoothes the amplified signals. A vibratory inertial force sensor adopting this method is also disclosed.
    Type: Application
    Filed: October 10, 2006
    Publication date: June 11, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Takeshi Uemura
  • Patent number: 7536910
    Abstract: An acceleration sensor, including: an oscillator unit for outputting an oscillator signal, the oscillator unit including a first piezoelectric vibrating reed having a vibrating arm that performs bending vibration, as well as an oscillator circuit for oscillating the first piezoelectric vibrating reed; a phase shifting unit for shifting and outputting a given phase angle of an output signal of the oscillator unit; a phase shift circuit unit provided with a second piezoelectric vibrating reed having a vibrating arm that performs bending vibration, arranged at an output side of the phase shifting unit; a multiplier for multiplying the output signal of the phase shift circuit unit by the output signal of the oscillator circuit; and a phase shift modification output unit which receives an output from the multiplier and outputs a value corresponding to a change in a phase shift angle of an input-output signal of the phase shift circuit unit; a resonant frequency of the second piezoelectric vibrating reed being equa
    Type: Grant
    Filed: July 16, 2007
    Date of Patent: May 26, 2009
    Assignee: Epson Toyocom Corporation
    Inventor: Jun Watanabe
  • Publication number: 20090126488
    Abstract: A tuning fork vibrator includes a vibrating body having the shape of a tuning fork as a whole. The vibrating body includes legs having a meandering shape and a base coupled to an end of the legs. A support is formed so as to extend between the legs from the base. Two electrodes arranged separately in the width direction are formed on one of the legs, and two electrodes arranged separately in the width direction are formed on the other of the legs. The outermost electrodes on each of the legs are connected to a connection electrode formed on the base. The connection electrode is formed so as to extend toward the support. The innermost electrodes on each of the legs are formed so as to extend toward the support through the base. A common electrode is formed on a second principal surface of the vibrating body. A vibratory gyroscope can be formed using the tuning fork vibrator.
    Type: Application
    Filed: January 16, 2009
    Publication date: May 21, 2009
    Inventors: Katsumi Fujimoto, Masato Koike
  • Patent number: 7533568
    Abstract: An angular rate sensor includes an oscillator having a pair of arm portions extending parallel to each other, a stem portion continuously formed to the arm portions, a driving member for oscillating the arm portions in directions opposite to each other, and a distortion detecting member for detecting a distortion of the arm portions in a distorted direction of the arm portions caused by a Coriolis force. The angular rate sensor further includes a correction driving member for driving the arm portions in the distorted direction of the arm portions, and a correction circuit for controlling the correction driving member to drive the arm portions in such a direction as to cancel a false distortion of the arm portions. The false distortion is detected by the distortion detecting member without the arm portions being subjected to the Coriolis force.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: May 19, 2009
    Assignee: Panasonic Corporation
    Inventor: Masayoshi Murakami
  • Publication number: 20090120186
    Abstract: A tuning fork gyro sensor includes a tuning fork vibrator and a casing. The tuning fork vibrator includes a pair of arms that extend parallel, a base that supports the pair of arms, and supporting members that are arranged on both faces of the base such that the supporting members are positioned at the equal distances from both the pair of arms, and that project from the both faces of the base, the both faces being perpendicular to both a direction in which the pair of arms extend and a direction in which the pair of arms are aligned. The casing is hollow to house and support the tuning fork vibrator by supporting the supporting members.
    Type: Application
    Filed: January 26, 2007
    Publication date: May 14, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Shigeo Matsunuma
  • Publication number: 20090120187
    Abstract: An inertial force sensor is composed of a plurality of arms and an oscillator having a base for linking the arms, in which a trimming slit is formed on a part of the arm except for a ridge portion, thus controlling damage to a tuning fork arm to be caused by the trimming.
    Type: Application
    Filed: April 10, 2007
    Publication date: May 14, 2009
    Applicant: PANASONIC CORPORATION
    Inventors: Satoshi Ohuchi, Hiroyuki Aizawa
  • Patent number: 7526957
    Abstract: A vibrating inertial rate sensor has sense elements that operate on axes that are rotationally skewed from a node reference axis, enabling both a rate sense and a drive sense determination. Alternatively, the skew may be applied to rotationally offset the drive elements from antinode reference axes to affect active torquing of the gyroscope. The skewed sensing scheme may be applied to vibratory systems having one or more node axes. The skewed drive scheme may be applied to vibratory systems having two or more node axes to affect active torquing.
    Type: Grant
    Filed: December 18, 2006
    Date of Patent: May 5, 2009
    Assignee: Watson Industries, Inc.
    Inventor: William S. Watson
  • Patent number: 7523537
    Abstract: Tuning fork and method in which a pair of elongated tines having front and rear surfaces are disposed symmetrically about an axis, and balancing masses on the front surface of one tine and on the rear surface of the other tine are trimmed to reduce quadrature error and also to maintain mass balance between the tines.
    Type: Grant
    Filed: July 13, 2000
    Date of Patent: April 28, 2009
    Assignee: Custom Sensors & Technologies, Inc.
    Inventors: Stuart J. Knowles, Robert H. Moore
  • Publication number: 20090058226
    Abstract: A tuning fork oscillating piece includes: a base; a pair of oscillating arms extending from the base in directions substantially parallel with each other; a drive piezoelectric element provided at least on one main surface or side surface of each of the oscillating arms to allow bending oscillation of the oscillating arms by piezoelectric distortion caused by applied charge; a detection piezoelectric element provided on the surface opposed to the surface of each of the oscillating arms on which the drive piezoelectric element is provided to convert the piezoelectric distortion caused by the bending oscillation of the oscillating arms into charge and output the charge. The drive piezoelectric element has a drive piezoelectric section. The detection piezoelectric element has a detection piezoelectric section. The absolute value of the piezoelectric d constant of the drive piezoelectric section is larger than the absolute value of the piezoelectric d constant of the detection piezoelectric section.
    Type: Application
    Filed: September 4, 2008
    Publication date: March 5, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Makoto Furuhata, Masahiro Oshio, Takamitsu Higuchi
  • Publication number: 20090044624
    Abstract: The present invention provides an angular velocity sensor having a stable characteristic in which a vibration element has a small variation in the driving efficiency even when carbon dioxide gas is generated by the reaction with oxygen gas in a package including therein the vibration element. To realize this, the angular velocity sensor of the present invention provides mixed gas of inert gas and oxygen gas in the package so that the mixed gas in the package has a pressure higher than the atmospheric pressure.
    Type: Application
    Filed: November 1, 2006
    Publication date: February 19, 2009
    Inventors: Michihiko Hayashi, Masakazu Hatanaka
  • Publication number: 20090031807
    Abstract: An angular velocity detection apparatus includes an angular velocity detection signal amplifier circuit which amplifies an angular velocity detection signal Vo output from an angular velocity sensor, and an offset control circuit which controls an offset so as to be a reference voltage which is output when a value of an angular velocity is 0. The angular velocity detection apparatus further includes an input switch circuit which selects the reference voltage and a discharge switch circuit which short-circuits a capacitor included in a high-pass filter in an offset control period.
    Type: Application
    Filed: October 23, 2008
    Publication date: February 5, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Hideaki SUGIBAYASHI
  • Patent number: 7481110
    Abstract: A method for quadrature-bias compensation in a Coriolis gyro whose resonator is in the form of a coupled system comprising a first and a second linear oscillator. The quadrature bias of the Coriolis gyro is determined. An electrostatic field is produced by variation of the mutual alignment of the two oscillators with respect to one another. The alignment/strength of the electrostatic field is regulated so that the determined quadrature bias is made as small as possible.
    Type: Grant
    Filed: November 26, 2004
    Date of Patent: January 27, 2009
    Assignee: LITEF GmbH
    Inventors: Eberhard Handrich, Wolfram Geiger
  • Patent number: 7478558
    Abstract: In a piezoelectric element, an adhesive layer 12 is provided on a substrate 11, a first electrode layer 14 made of a noble metal containing titanium or titanium oxide is provided on the adhesive layer 12, and an orientation control layer 15 that is preferentially oriented along a (100) or (001) plane is provided on the first electrode layer 14. In the vicinity of a surface of the orientation control layer 15 that is closer to the first electrode layer 14, a (100)- or (001)-oriented region extends over titanium or titanium oxide located on one surface of the first electrode layer 14 that is closer to the orientation control layer 15, and the cross-sectional area of the region in the direction perpendicular to the thickness direction gradually increases in the direction away from the first electrode layer 14 toward the opposite side. Further, a piezoelectric layer 16 that is preferentially oriented along a (001) plane is provided on the orientation control layer 15.
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: January 20, 2009
    Assignee: Panasonic Corporation
    Inventors: Eiji Fujii, Hideo Torii, Ryoichi Takayama, Atsushi Tomozawa, Akiko Murata, Taku Hirasawa
  • Publication number: 20090013784
    Abstract: A composite sensor includes an angular velocity sensor element, an acceleration sensor element, a signal processing IC for processing signals from the angular velocity sensor element and the acceleration sensor element, an inner package for accommodating the angular velocity sensor element, the acceleration sensor element, and the signal processing IC; a coupler connected to this inner package, and a fixing member connected to this coupler for holding the inner package via this coupler. The coupler is elastically deformable. One of the acceleration sensor element and the signal processing IC is located at the right with respect to the center of the inner package, and the other of the acceleration sensor element and the signal processing IC is located at the left with respect to the center of the inner package.
    Type: Application
    Filed: March 14, 2007
    Publication date: January 15, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Hideo Ohkoshi
  • Publication number: 20090007665
    Abstract: A tuning-fork-type bimorph piezoelectric vibrator includes two piezoelectric bodies that are bonded together and have opposite polarization directions. An intermediate metal layer is disposed between bonding surfaces of the piezoelectric bodies. A first slit is arranged to define legs and a base of the tuning fork structure. Second slits are provided in a first principal surface having a front metal layer to define driving/detecting electrodes. The tuning-fork-type bimorph piezoelectric vibrator provides improved temperature characteristics of a detuning frequency by not including a back metal layer on a second principal surface at least in an area in which greater than a predetermined level of stress is applied during operation.
    Type: Application
    Filed: September 18, 2008
    Publication date: January 8, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Haruyoshi KURAKAWA
  • Publication number: 20090007664
    Abstract: A vibration gyro made of a single crystal piezoelectric material includes: a base; a plurality of resonating arms extending from the base; an excitation electrode formed on a surface of at least one of the plurality of resonating arms so as to vibrate at least the one of the plurality of resonating arms; and a piezoelectric element detecting a vibration component due to a Coriolis force acting perpendicularly to a vibrating direction of the plurality of resonating arms being vibrated by the excitation electrode, the piezoelectric element being mounted on a surface of at least one of the plurality of resonating arms and the base.
    Type: Application
    Filed: June 30, 2008
    Publication date: January 8, 2009
    Applicant: EPSON TOYOCOM CORPORATION
    Inventors: Takayuki KIKUCHI, Norifumi SHIMIZU
  • Publication number: 20090007666
    Abstract: A vibrating gyroscope includes a tuning-fork vibrator having a base and legs. The vibrator is joined to a support plate by conductive adhesive members. The support plate includes an outer frame portion in which a joining portion is provided at a location near a longitudinal end of the outer frame portion. The joining portion is supported by a first support portion in the air gap portion. The width of the first support portion is less than the width of the joining portion. The vibrator is joined to the joining portion of the support plate.
    Type: Application
    Filed: September 23, 2008
    Publication date: January 8, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Shinya OGURI, Masato KOIKE, Haruyoshi KURAKAWA, Katsumi FUJIMOTO
  • Publication number: 20080314145
    Abstract: An angular velocity detection apparatus includes: a sensor unit having first and second detection axes serving as angular velocity detection axes, the first and second detection axes intersecting each other; a sensor output correction circuit for making at least one of an offset adjustment and a sensitivity adjustment to a detection output of an angular velocity around the first detection axis and a detection output of an angular velocity around the second detection axis; a sign determination circuit for obtaining a sign of a rotational direction of an angular velocity on any one of the first and second detection axes; and an amplitude calculation circuit for multiplying a square sum average of detection outputs of angular velocities around the first and second detection axes outputted by the sensor output correction circuit and a sign outputted by the sign determination circuit.
    Type: Application
    Filed: June 19, 2008
    Publication date: December 25, 2008
    Applicant: EPSON TOYOCOM CORPORATION
    Inventor: Kenji SATO
  • Patent number: 7456555
    Abstract: The present invention provides an angular velocity sensor and a method of fabrication thereof that facilitates the work of affixing a tuning-fork-type crystal element and adjusting the same, preventing waste caused by scrapping defective products and also encouraging miniaturization of components.
    Type: Grant
    Filed: January 24, 2006
    Date of Patent: November 25, 2008
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Hideryo Matsudo, Masahiro Yoshimatsu, Takahiro Inoue, Kenichi Kikuchi
  • Patent number: 7441459
    Abstract: The invention provides a tuning-fork type transducer for an angular-speed sensor which realizes a stable fork-driving, realizes downsizing of the angular-speed sensor, and is capable of executing control of a vehicle body with high degree of accuracy when being used under a high-temperature environment, an angular-speed sensor using this transducer, and an automotive vehicle using this angular-speed sensor. Electric charges obtained from upper electrodes (13a), (14a) provided on an arm (10b) are amplified respectively by current amplifiers (40a), (40b). The amplified signal is differentially amplified by a first differential amplifier (41), and the amplified signal is used as a monitor signal for fork-driving. An added signal obtained by adding output signals from the current amplifiers (40a), (40b) by an adder (60) is used as a signal for detecting the angular speed.
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: October 28, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Satoshi Ohuchi, Takeshi Yamamoto, Hiroyuki Aizawa
  • Publication number: 20080236281
    Abstract: An angular velocity sensor of a horizontally located type, in which influence of a translational acceleration applied thereto from a lateral direction is readily removed and a fixed portion thereof is easily fixed, is provided. It includes a fixed portion fixed to the top surface of a sensor element supporting portion of a casing, an upper detection arm portion and a lower detection arm portion respectively connected to the fixed portion on sides opposite to each other and extending along a plane parallel to the top surface of the sensor element supporting portion, and a pair of upper vibration arms connected to the fixed portion with the upper detection arm portion in between. The fixed portion includes one or more slits extending at least in a direction intersecting with the extending direction of the upper detection arm portion.
    Type: Application
    Filed: March 26, 2008
    Publication date: October 2, 2008
    Applicant: TDK CORPORATION
    Inventors: Takao Noguchi, Kenichi Tochi, Ken Unno, Tatsuo Namikawa
  • Publication number: 20080229824
    Abstract: An angular rate sensor includes: a piezoelectric vibration device; and a detection section, wherein the piezoelectric vibration device includes a base substrate, a vibration section having a fixed end affixed to the base substrate and a free end that does not contact the base substrate, and a driving section formed above the vibration section for generating flexural vibration of the vibration section; the vibration section has a first support section, four (first-fourth) cantilever sections supported by the first support section, and a second support section that supports the first support section and equipped with the fixed end; the first support section has two center lines that are orthogonal to each other; the first cantilever section and the second cantilever section are symmetrical to each other through one of the center lines of the first support section in a plan view; the third cantilever section and the fourth cantilever section are symmetrical to each other through the one of the center lines of th
    Type: Application
    Filed: March 18, 2008
    Publication date: September 25, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Takamitsu HIGUCHI, Yasuhiro ONO
  • Patent number: 7426861
    Abstract: A tuning fork gyroscope design where at least one proof mass is supported above a substrate. At least one drive electrode is also supported above the substrate adjacent the proof mass. Typically, the proof mass and the drive electrode include interleaved electrode fingers. A sense plate or shield electrode on the substrate beneath the proof mass extends completely under the extent of the electrode fingers of proof mass.
    Type: Grant
    Filed: June 15, 2005
    Date of Patent: September 23, 2008
    Assignee: The Charles Stark Draper Laboratory, Inc.
    Inventors: Marc S. Weinberg, Jonathan Bernstein, Jeffrey T. Borenstein, Richard Elliott, Gregory Kirkos, Anthony S. Kourepenis
  • Publication number: 20080210006
    Abstract: An angular velocity sensor includes a tuning-fork oscillator that includes a base portion, arm portions extending from the base portion, and a pair of driving electrodes that are provided to extend from the front face and the back face to a side face of at least one of the arm portions.
    Type: Application
    Filed: December 21, 2007
    Publication date: September 4, 2008
    Inventors: Yuki Endo, Hiroshi Tanaka, Tomoaki Momose, Masanori Yachi
  • Publication number: 20080210007
    Abstract: An angular velocity sensor includes: a first tuning-fork vibrator having a first base and first aims extending from the first base in a first direction; a second tuning-fork vibrator having a second bass and second arms extending from the second base in a second direction; and a double gimbal portion mat has a drive gimbal portion vibrating about an axis extending in a fourth direction, and a sense gimbal portion vibrating about an axis extending in a fifth direction and senses an angular velocity about an axis extending in a third direction.
    Type: Application
    Filed: January 23, 2008
    Publication date: September 4, 2008
    Inventors: Takayuki Yamaji, Hiroshi Ishikawa, Yuji Takahashi, Takashi Katsuki, Fumihiko Nakazawa, Hiroaki Inoue
  • Publication number: 20080202238
    Abstract: An angular velocity sensor includes a tuning-fork vibrator having a base and multiple arms extending from the base. Two arms out of the multiple arms driven to vibrate have first end parts opposite to second end parts connected to the base. The first end parts being wider than the second end parts.
    Type: Application
    Filed: February 25, 2008
    Publication date: August 28, 2008
    Applicant: FUJITSU MEDIA DEVICES LIMITED
    Inventors: Hiroshi TANAKA, Yuki Endo, Masanori Yachi, Kazutaka Araya, Yoshinori Uwano
  • Patent number: 7412885
    Abstract: A vibrating gyro element includes in the same plane a base portion; a pair of vibrating arms for detection extended out of the base portion on both sides in a straight line shape; a pair of connecting arms extended-out from the base portion onto both sides in directions perpendicular to the vibrating arms for detection; a pair of vibrating arms for driving each extended-out from the tip portion of each of the connecting arms to both sides perpendicularly to this tip portion; two pairs of beams extended out of the base portion along the respective arms for detection; and a pair of support portions to which the respective beams extended out in the same direction are connected; wherein the support portion is arranged outside the vibrating arm for detection between the vibrating arms for driving in the extending-out direction of each of the vibrating arms for detection.
    Type: Grant
    Filed: January 10, 2006
    Date of Patent: August 19, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Seiichiro Ogura
  • Patent number: 7412886
    Abstract: A transducer for measuring an angular velocity formed by a single piezoelectric tuning fork (21) that rotates at the angular velocity. The tuning fork has a detection leg (24) which has a cross-shaped section including two top lateral faces (33, 34) and two bottom lateral faces (37, 38) separated by protruding parts (41, 42) projecting with respect to the faces. The detection leg has detecting electrodes which are arranged such that the electrical field between electrodes is substantially rectilinear through the detection leg.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: August 19, 2008
    Assignee: ETA SA Manufacture Horlogere Suisse
    Inventors: Silvio Dalla Piazza, Bruno Studer