Patents by Inventor Ryoichi Ichikawa

Ryoichi Ichikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20130002096
    Abstract: A piezoelectric device includes a piezoelectric vibrating plate, a first plate, a first glass sealing material disposed in a ring shape, and an electrically conductive adhesive. The piezoelectric vibrating plate includes a piezoelectric vibrating piece, a frame body, and a pair of extraction electrodes. The piezoelectric vibrating piece includes a pair of excitation electrodes. The frame body surrounds the piezoelectric vibrating piece. The frame body is formed integrally with the piezoelectric vibrating piece. The first glass sealing material encloses a periphery of the first main surface of the frame body so as to bond the first plate and the first main surface of the frame body together.
    Type: Application
    Filed: June 27, 2012
    Publication date: January 3, 2013
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: MITOSHI UMEKI, RYOICHI ICHIKAWA
  • Publication number: 20120326566
    Abstract: In an external force detection apparatus, a crystal plate is cantilevered within a container. Excitation electrodes are formed on the top surface and the bottom surface of the crystal plate. A movable electrode is formed on a distal end on the bottom surface of the crystal plate and is connected to the excitation electrode on the bottom surface via an extraction electrode. A fixed electrode is provided on the bottom of the container to oppose the movable electrode. The excitation electrode on the top surface and the fixed electrode are connected to an oscillating circuit. When an external force acts on the crystal plate to bend it, the capacitance between the movable electrode and the fixed electrode changes, and this capacitance change is captured as a change in the oscillating frequency of the crystal plate.
    Type: Application
    Filed: June 21, 2012
    Publication date: December 27, 2012
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: MITSUAKI KOYAMA, TAKERU MUTOH, HIROKI IWAI, RYOICHI ICHIKAWA
  • Publication number: 20120312097
    Abstract: An acceleration measuring apparatus that can easily detect acceleration with high accuracy is provided. In the apparatus, positional displacement of a swingable pendulum member is detected, feedback control is performed to maintain the pendulum member in a stationary state using an actuator, and acceleration is measured by measuring the output of the actuator at this time. A movable electrode is provided to the pendulum member, and a loop is formed in which a fixed electrode provided to oppose the movable electrode, and an oscillating circuit, a crystal unit, and the movable electrode are electrically connected in series. By measuring an oscillating frequency of the oscillating circuit at this time, a change in the size of a variable capacitance formed between the movable electrode and the fixed electrode is detected, and thereby the positional displacement of the pendulum member is detected.
    Type: Application
    Filed: June 5, 2012
    Publication date: December 13, 2012
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: MITSUAKI KOYAMA, TAKERU MUTOH, HIROKI IWAI, RYOICHI ICHIKAWA
  • Publication number: 20120306320
    Abstract: The present disclosure provides the piezoelectric devices in which the bonding condition of devices can be easily observed. The piezoelectric device (100) comprises: a piezoelectric vibrating piece that vibrates when electrically energized; a first plate (110) and a second plate (120) fabricated by transparent materials; and a sealing material (150a) formed in between the first plate and second plate and in periphery of the first plate and second plate, the sealing material having a slit (151b) within the predetermined width (WX, WZ) of the sealing material.
    Type: Application
    Filed: June 1, 2012
    Publication date: December 6, 2012
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: Ryoichi Ichikawa, Yoshiaki Amano
  • Patent number: 8303755
    Abstract: Methods are disclosed for manufacturing piezoelectric devices. An exemplary method comprises the step of bonding a lid wafer, a piezoelectric frame wafer (having a vibrating piece and a outer frame surrounding the vibrating piece), and a base wafer (having at least one wiring through-hole) together. A surface of a unit (typically ball-shaped) of eutectic metal is cleaned and then arranged on the through-hole. The unit of eutectic metal is then melted in a vacuum or inert gas environment to allow the eutectic metal to enter the through-hole.
    Type: Grant
    Filed: October 6, 2009
    Date of Patent: November 6, 2012
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Ryoichi Ichikawa, Mitoshi Umeki
  • Patent number: 8278798
    Abstract: An object is to provide a crystal device that uses a mesa-structure crystal piece in which frequency adjustment is possible. A configuration is such that in a crystal device having: a crystal piece having a thick portion and a thin portion, with an excitation electrode formed on both main faces of the thick portion, and a lead out electrode electrically connected to the excitation electrode, formed on an end portion; a container main body having a concavity for accommodating the crystal piece; and a cover that is connected to an open end face of the container main body and hermetically seals the crystal piece, a frequency adjustment metal film which is electrically isolated from the excitation electrode and made independent, is formed on the thin portion of the crystal piece.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: October 2, 2012
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Ryoichi Ichikawa
  • Patent number: 8227958
    Abstract: An exemplary piezoelectric vibrating device includes a piezoelectric frame that supports and surrounds a tuning-fork type piezoelectric vibrating piece having a pair of vibrating arms. The device also includes a lid and a package base that are siloxane-bonded to the frame. The lid defines at least one frequency-adjustment hole extending through the thickness dimension of the lid from an inner major surface thereof (facing the frame) to an outer major surface of the lid. The package base defines at least one through-hole electrode passing via a respective electrode through-hole through the thickness of the base from an inner major surface thereof (facing the frame) to the outer major surface thereof. The electrode is connected to the piezoelectric vibrating piece. The lid and base include external electrodes, made of an electrically conductive material, that cover the through-holes and frequency-adjustment hole(s).
    Type: Grant
    Filed: February 10, 2010
    Date of Patent: July 24, 2012
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Takahiro Inoue, Takefumi Saito, Mitoshi Umeki, Ryoichi Ichikawa
  • Publication number: 20120180568
    Abstract: A device is provided for a detecting external force applied to piezoelectric piece. A crystal piece is cantilever-supported in a container. Excitation electrodes are formed on an upper face and lower face, respectively. A movable electrode, connected via a lead-out electrode to the excitation electrode, is formed on the lower face side at a front end of the crystal piece. A fixed electrode is provided on a bottom portion of the container to face this movable electrode. The excitation electrode on the upper face side and the fixed electrode are connected to an oscillation circuit. When the crystal piece bends in response to an applied external force, capacitance between the movable electrode and fixed electrode, changes. This capacitance change results in a corresponding change in oscillation frequency of the crystal piece.
    Type: Application
    Filed: January 11, 2012
    Publication date: July 19, 2012
    Applicant: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitsuaki KOYAMA, Takeru MUTOH, Hiroki IWAI, Yoshiaki AMANO, Ryoichi ICHIKAWA
  • Publication number: 20120139499
    Abstract: According to one embodiment, the economical load dispatcher calculates a discharging threshold value and a charging threshold value based on a discharging unit price of and a charging and discharging efficiency of the secondary battery and further calculates output allocations of the generators and secondary battery such that the secondary battery is discharged when incremental fuel costs of the generators are higher than the discharging threshold value, whereas the secondary battery is charged when incremental fuel costs of the generators are lower than the charging threshold value.
    Type: Application
    Filed: February 15, 2012
    Publication date: June 7, 2012
    Inventors: Mari Tanaka, Takenori Kobayashi, Koji Toba, Yoshihiro Ogita, Ryoichi Ichikawa, Akinori Nishi
  • Patent number: 8154178
    Abstract: In the disclosed piezoelectric devices a piezoelectric frame includes a vibrating piece. An excitation electrode is formed on the vibrating piece. An outer frame portion surrounds the vibrating piece and includes an extraction electrode connected to the excitation electrode. A package base is bonded to one surface of the outer frame portion and includes a connection electrode connected to the extraction electrode. The package base includes an external terminal formed on a surface thereof opposite the surface on which the connection electrodes are formed. Through-hole conductors connected the connection electrodes with respective external terminals. A lid is bonded to an opposing surface of the piezoelectric frame. An exhaust channel is in communication with the extraction electrode adjacent the through-hole conductors.
    Type: Grant
    Filed: July 27, 2009
    Date of Patent: April 10, 2012
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Ryoichi Ichikawa, Mitoshi Umeki
  • Publication number: 20120068579
    Abstract: The present disclosure provides a method for manufacturing piezoelectric devices by using a base wafer having through-holes manufactured in precise size. In the method for manufacturing a piezoelectric device comprises: a step of: forming an anticorrosive film (S121) on a first surface and on a second surface opposing the first surface of the base wafer made of a glass or a piezoelectric material; after forming a photoresist on the anticorrosive film and exposing, metal-etching the anticorrosive film (S121, S122) corresponding to the through-hole; after the metal-etching step, applying an etching solution onto the glass or the piezoelectric material and wet-etching (S123) the first surface and the second surface of the base wafer until before completely cutting through the glass or the piezoelectric material; and applying an abrasive from the second surface with the anticorrosive film remaining in place on the second surface, by sand-blasting method (S124).
    Type: Application
    Filed: September 21, 2011
    Publication date: March 22, 2012
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: Ryoichi Ichikawa, Yoshiaki Amano, Kenji Kamezawa
  • Publication number: 20120049695
    Abstract: Methods are disclosed for manufacturing piezoelectric vibrating devices that do not contain any unwanted gas or water vapor inside the devices. In an exemplary method, a base wafer is prepared including multiple package bases each having a first main surface and a second main surface. The base wafer also includes a pair of through-holes disposed between adjacent package bases of the base wafer. A piezoelectric vibrating piece is placed on each package base. A lid wafer is prepared that includes multiple package lids. A sealing material is applied to the base wafer or lid wafer in peripheral bands used for bonding the bases and lids together and defines respective interior cavities. The band of sealing material includes a communicating groove that communicates from the inner cavity to the first through-hole. The base wafer and lid wafer are subject to heat and compression to effect bonding.
    Type: Application
    Filed: August 19, 2011
    Publication date: March 1, 2012
    Inventor: Ryoichi Ichikawa
  • Publication number: 20120043860
    Abstract: Piezoelectric vibrating devices are disclosed that lack base through-holes and that can be manufactured on a wafer scale. Also disclosed are methods for making same. An exemplary piezoelectric device has a package base having first and second opposing main surfaces. On the second (outer) first main surface is formed a pair of external electrodes. The first (inner) main surface defines a first recess and a peripheral first bonding surface. A pair of connecting electrodes are provided for connecting to the respective external electrodes via respective edge surfaces of the package base that extend between the first and second main surfaces. A piezoelectric vibrating piece is mounted in and contained within the package base. The vibrating piece includes a pair of excitation electrodes electrically connected to respective connecting electrodes. A package lid comprises first and second main surfaces, of which the second (inner) main surface defines a second recess that is larger than the first recess.
    Type: Application
    Filed: August 17, 2011
    Publication date: February 23, 2012
    Inventors: Ryoichi Ichikawa, Yoshiaki Amano
  • Publication number: 20120043859
    Abstract: To provide a piezoelectric device prevented from overflowing of sealing materials. The piezoelectric device (100) stores a piezoelectric vibrating piece (30) having a pair of excitation electrodes. The piezoelectric device comprises: a package lid (10), including a first bonding surface (M1) formed in periphery of the package lid in a circumferential pattern and a lid recess (10); a package base (30), including a second bonding surface (M2), a base recess surrounded by a second bonding surface that is higher than the second bonding surface, and a pair of seats that is protruding from the base recess, situated for mounting the piezoelectric piece; a piezoelectric piece mounted onto the pair of seats; and a non electric conductive sealing material (48) disposed peripherally in relative to the first bonding surface and the second bonding surface in a circumferential pattern, thus the adhesive bonding the first bonding surface and the second bonding surface.
    Type: Application
    Filed: August 12, 2011
    Publication date: February 23, 2012
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: Ryoichi Ichikawa, Yoshiaki Amano, Kenji Kamezawa
  • Patent number: 8093787
    Abstract: Tuning-fork-type crystal vibrating pieces are disclosed that have a base and a pair of vibrating arms extending from one side of the base in a designated longitudinal direction. A root portion is situated between the vibrating arms, and includes a first taper surface. Extending outboard of the vibrating arms from respective sides of the base are respective supporting arms that extend in the designated direction. Between each supporting arm and the respective vibrating arm is a respective supporting-arm root portion. Each supporting-arm root portion has a second taper surface in the thickness direction of the base.
    Type: Grant
    Filed: October 6, 2009
    Date of Patent: January 10, 2012
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Ryoichi Ichikawa
  • Publication number: 20110316390
    Abstract: An exemplary piezoelectric vibrating device includes a piezoelectric vibrating piece that vibrates when electrically energized. A first package plate has a main recess in which the piezoelectric vibrating piece is placed, and a peripheral surface surrounding the recess. A second package plate is bonded to the peripheral surface of the first package plate in airtight manner. A band of adhesive bonds the first package plate to the second package plate. The adhesive band surrounds the peripheral surface. Between the adhesive and the main recess is a band of metal film. The band of metal film prevents gas, generated from the adhesive, from flowing into the recess. The band of metal film surrounds the peripheral surface and is disposed inboard of the band of adhesive.
    Type: Application
    Filed: June 20, 2011
    Publication date: December 29, 2011
    Inventors: Mitoshi Umeki, Ryoichi Ichikawa, Yoshiaki Amano, Kenji Kamezawa, Kenichi Kikuchi, Noritsugu Matsukura
  • Publication number: 20110260585
    Abstract: Piezoelectric devices are disclosed that are mountable on the surface of a printed circuit board or the like. An exemplary device comprises a piezoelectric vibrating piece enclosed and sealed within a package including at least a cover and a base-substrate formed of glass or piezoelectric material. The package includes frame-shaped metallic films formed in peripheral regions of inner main surfaces of the cover and/or the base substrate. The frame-shaped metallic films are used for sealing the package using a eutectic material (e.g., solder). At least one mounting terminal is provided on the outer (bottom) main surface of the base-substrate. At least one of the frame-shaped metallic films and mounting terminals includes a chromium foundation layer formed on the surface of the glass or piezoelectric material, a middle layer of NiW alloy formed on the surface of the chromium layer, and a gold layer formed on the surface of the middle layer.
    Type: Application
    Filed: April 22, 2011
    Publication date: October 27, 2011
    Inventors: Ryoichi Ichikawa, Shuichi Mizusawa
  • Patent number: 8018126
    Abstract: Surface-mounted piezoelectric devices are disclosed that include a package having a base and a lid made of a piezoelectric material or of glass. The package defines an internal cavity containing a tuning-fork type crystal vibrating piece having a pair of vibrating arms. The volume of the cavity is at least twelve times the volume of the pair of vibrating arms. Piezoelectric devices having these characteristics exhibit reduced CI degradation.
    Type: Grant
    Filed: August 18, 2010
    Date of Patent: September 13, 2011
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitoshi Umeki, Takefumi Saito, Ryoichi Ichikawa
  • Publication number: 20110140572
    Abstract: An object is to provide a crystal device that uses a mesa-structure crystal piece in which frequency adjustment is possible. A configuration is such that in a crystal device having: a crystal piece having a thick portion and a thin portion, with an excitation electrode formed on both main faces of the thick portion, and a lead out electrode electrically connected to the excitation electrode, formed on an end portion; a container main body having a concavity for accommodating the crystal piece; and a cover that is connected to an open end face of the container main body and hermetically seals the crystal piece, a frequency adjustment metal film which is electrically isolated from the excitation electrode and made independent, is formed on the thin portion of the crystal piece.
    Type: Application
    Filed: December 8, 2010
    Publication date: June 16, 2011
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventor: Ryoichi Ichikawa
  • Publication number: 20110068659
    Abstract: Methods are disclosed for manufacturing piezoelectric vibrating devices. An exemplary method includes preparing a base wafer defining multiple bases each including stripes of a first bonding film extending along respective edges of the bases and first indents adjacent to and contacting respective stripes of the first bonding film. Also prepared is a lid wafer defining multiple lids each including stripes of a second bonding film extending along respective edges of the lids and second indents adjacent to and contacting respective stripes of the second bonding film. A unit of bonding material (e.g., a bonding “ball”) is applied to each of the first indents or to each of the second indents. Bonding together the base wafer and lid wafer is completed by melting the bonding material to flow the bonding material along the stripes, followed by solidifying the bonding material.
    Type: Application
    Filed: September 23, 2010
    Publication date: March 24, 2011
    Inventor: Ryoichi Ichikawa