Patents by Inventor Hiroki Iwai

Hiroki Iwai 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).

  • Patent number: 11909342
    Abstract: Two inverters (10) provided at respective both ends of open-end windings (8) are appropriately controlled. As control regions (R) of a rotating electrical machine (80), a first speed region (VR1) and a second speed region (VR2) in which the rotational speed of the rotating electrical machine (80) is higher than in the first speed region (VR1) for the same torque are set, and in the second speed region (VR2), a rotating electrical machine control device (1) controls both inverters (10), a first inverter (11) and a second inverter (12), by mixed pulse width modulation control in which control is performed such that a plurality of pulses with different patterns are outputted during a first period (T1) which is a half cycle of electrical angle, and an inactive state continues during a second period (T2) which is the other half cycle.
    Type: Grant
    Filed: September 29, 2020
    Date of Patent: February 20, 2024
    Assignees: AISIN CORPORATION, NAGOYA INSTITUTE OF TECHNOLOGY
    Inventors: Subrata Saha, Hiroki Iwai, Takashi Kosaka, Hiroaki Matsumori, Naoto Saito, Yoshinobu Ito, Isao Fujiwara
  • Publication number: 20230261604
    Abstract: In a first control state, it is determined which one of a first failure pattern (FP1) and a second failure pattern (FP2) is a failure pattern (FT), and in a second control state, it is determined which one of a first lower-stage-side failure pattern (LF1) and a second lower-stage-side failure pattern (LF2) is a lower-stage-side failure pattern (LF), and it is determined which one of a set of upper-stage-side arms of a first inverter (11), a set of lower-stage-side arms of the first inverter (12), a set of upper-stage-side arms of a second inverter (12), and a set of lower-stage-side arms of the second inverter (12) is failure-side arms, based on a result of the determination in the first control state and a result of the determination in the second control state.
    Type: Application
    Filed: March 26, 2021
    Publication date: August 17, 2023
    Applicants: AISIN CORPORATION, NAGOYA INSTITUTE OF TECHNOLOGY
    Inventors: Subrata SAHA, Hiroki IWAI, Takashi KOSAKA, Hiroaki MATSUMORI
  • Publication number: 20230028358
    Abstract: Two inverters (10) provided at respective both ends of open-end windings (8) are appropriately controlled. As control regions (R) of a rotating electrical machine (80), a first speed region (VR1) and a second speed region (VR2) in which the rotational speed of the rotating electrical machine (80) is higher than in the first speed region (VR1) for the same torque are set, and in the second speed region (VR2), a rotating electrical machine control device (1) controls both inverters (10), a first inverter (11) and a second inverter (12), by mixed pulse width modulation control in which control is performed such that a plurality of pulses with different patterns are outputted during a first period (T1) which is a half cycle of electrical angle, and an inactive state continues during a second period (T2) which is the other half cycle.
    Type: Application
    Filed: September 29, 2020
    Publication date: January 26, 2023
    Applicants: AISIN CORPORATION, NAGOYA INSTITUTE OF TECHNOLOGY
    Inventors: Subrata SAHA, Hiroki IWAI, Takashi KOSAKA, Hiroak MATSUMORI, Naoto SAITO, Yoshinobu ITO, Isao FUJIWARA
  • Publication number: 20230006594
    Abstract: A rotary electric machine control apparatus (1) suitably controls two inverters (10) connected to associated ends of open windings (8). The rotary electric machine control apparatus (1) performs target control involving: controlling a first one of the inverters (10), which is selected from a first inverter (11) and a second inverter (12), by rectangular wave control; and controlling a second one of the inverters (10) by special pulse width modulation control that is one type of pulse width modulation control. The special pulse width modulation control is a control method to produce a switching pattern (Su2+) that is based on a difference between a switching pattern resulting from the pulse width modulation control and a switching pattern (Su1+) resulting from the rectangular wave control when a target voltage is to be generated in the open windings (8).
    Type: Application
    Filed: September 29, 2020
    Publication date: January 5, 2023
    Applicants: AISIN CORPORATION, NAGOYA INSTITUTE OF TECHNOLOGY
    Inventors: Subrata SAHA, Hiroki IWAI, Takashi KOSAKA, Hiroaki MATSUMORI
  • Patent number: 9016128
    Abstract: A technique for detecting external force applied to a piezoelectric plate is provided. A crystal plate is cantilever-supported in a container. Excitation electrodes are formed on an upper face and lower face, respectively, of the crystal plate. A movable electrode is formed on the lower face side. A fixed electrode is provided on a bottom portion of the container facing the movable electrode. The excitation electrode on the upper face side and the fixed electrode are connected to an oscillation circuit. When the crystal plate bends by external force applied, capacitance between. A direction of the movable electrode along a length direction of the crystal plate is set to 30° to 60°, relative to a face orthogonal to an intended direction of the external force. The movable electrode and fixed electrode changes, and this capacitance change and a deformation of the crystal circuit.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: April 28, 2015
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitsuaki Koyama, Takeru Mutoh, Hiroki Iwai
  • Patent number: 8966980
    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: Grant
    Filed: January 11, 2012
    Date of Patent: March 3, 2015
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitsuaki Koyama, Takeru Mutoh, Hiroki Iwai, Yoshiaki Amano, Ryoichi Ichikawa
  • Patent number: 8933615
    Abstract: A piezoelectric device including a tuning-fork piezoelectric vibrating element having a base and a pair of vibrating arms positioned parallel to each other and extending from the base at right angles. The piezoelectric device further including a pair of support arms extending from the base positioned parallel to each other and in the same direction as the vibrating arms. A package is included having a lid and a housing recess sealed by the lid wherein the tuning-fork piezoelectric vibrating element is housed. A pair of supports are provided on a bottom face of the housing recess for fixing the tuning-fork piezoelectric vibrating element by the support arms. A clearance groove is formed in the bottom face of the housing access to prevent the tuning-fork piezoelectric vibrating element from colliding against the bottom face of the housing recess.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: January 13, 2015
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Shunsuke Ueno, Shingo Kawanishi, Hiroki Iwai
  • Patent number: 8919201
    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: Grant
    Filed: June 5, 2012
    Date of Patent: December 30, 2014
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitsuaki Koyama, Takeru Mutoh, Hiroki Iwai, Ryoichi Ichikawa
  • Patent number: 8890391
    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: Grant
    Filed: June 21, 2012
    Date of Patent: November 18, 2014
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitsuaki Koyama, Takeru Mutoh, Hiroki Iwai, Ryoichi Ichikawa
  • Patent number: 8736152
    Abstract: An exemplary tuning-fork type piezoelectric vibrating piece has a rectangular base having upper and lower main surfaces and a pair of vibrating arms extending longitudinally from the base. The vibrating arms also have the upper and lower main surfaces. Each main surface of each vibrating arm defines a respective vibrating-arm groove extending longitudinally into the base. Each main surface of the base has at least one respective step-side surface situated outboard, in an X-axis direction, of each vibrating-arm groove. Each step-side surface is parallel with the respective vibrating-arm groove. A first electrode is situated on the vibrating-arm grooves of the first vibrating arm and on the at least one respective step-side surface on each main surface. A second electrode is situated on the vibrating-arm grooves of the second vibrating arm and on the at least one respective step-side surface on each main surface. The first and second electrodes are energized with different electrical polarities.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: May 27, 2014
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Hiroki Iwai
  • Patent number: 8729780
    Abstract: Piezoelectric vibrating pieces are disclosed that include a base, a pair of vibrating arms, and a pair of supporting arms. The base is fabricated of piezoelectric material. The vibrating arms extend straight from the base in a designated longitudinal direction and having a first thickness. A respective supporting arm extends straight from the base and outboard of each vibrating arm in the designated longitudinal direction. Each supporting arm includes at least a respective second region that has second thickness different from the first thickness.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: May 20, 2014
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Hiroki Iwai
  • Patent number: 8610338
    Abstract: A tuning-fork type piezoelectric vibrating piece (20) is comprised of a base portion (23) comprising a piezoelectric material, a pair of vibrating arms (21) extends parallel from the base portion with a first thickness, a excitation electrode film (33, 34) formed on the vibrating arms, a pair of tuning portions (28) formed at the distal ends of the vibrating arms (21) with a second thickness which is less than the first thickness; and a metal film (18) formed on at least one surface of the tuning portion.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: December 17, 2013
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Ryoichi Ichikawa, Hiroki Iwai, Yoshiaki Amano
  • Patent number: 8525491
    Abstract: The vehicle generator includes an armature winding, a switching section constituted as a bridge circuit including a plurality of pairs of an upper arm and a lower arm to rectify phase voltages of the armature winding, each of the upper and lower arms being constituted of a switching element parallel-connected with a diode, and a control section for controlling on/off timings of the switching elements. The control section is configured to perform switching operation to switch the switching section between a first operation state where each upper arm is turned off when the phase voltage is higher than a voltage of a vehicle battery, and a second operation state where each upper arm is turned off after the phase voltages becomes lower than the battery voltage, and configured to delay off timings of the switching elements stepwise when the switching section is in the second operation state.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: September 3, 2013
    Assignee: Denso Corporation
    Inventor: Hiroki Iwai
  • Patent number: 8390180
    Abstract: An object of the invention is to provide a surface mounted resonator that improves impact resistance by the shape of a mounting terminal provided on an outside bottom face of a stacked resonator. A surface mounted crystal resonator is provided with a plurality of mounting terminals electrically connected to a hermetically sealed crystal piece at both ends of an outside bottom face having a rectangular shape long in the lengthwise direction, the mounting terminals having the same external dimensions with a total dimension of the mounting terminals in a lengthwise direction of the outside bottom face being 70% or more [but less than 100%] of a dimension in the lengthwise direction of the outside bottom face. Respective facing sides of the mounting terminals facing each other in a central area of the outside bottom face are formed curved in a convex shape such that a curvature thereof decreases gradually.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: March 5, 2013
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Hiroki Iwai
  • 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: 20120293048
    Abstract: A piezoelectric device including a tuning-fork piezoelectric vibrating element having a base and a pair of vibrating arms positioned parallel to each other and extending from the base at right angles. The piezoelectric device further including a pair of support arms extending from the base positioned parallel to each other and in the same direction as the vibrating arms. A package is included having a lid and a housing recess sealed by the lid wherein the tuning-fork piezoelectric vibrating element is housed. A pair of supports are provided on a bottom face of the housing recess for fixing the tuning-fork piezoelectric vibrating element by the support arms. A clearance groove is formed in the bottom face of the housing access to prevent the tuning-fork piezoelectric vibrating element from colliding against the bottom face of the housing recess.
    Type: Application
    Filed: March 14, 2012
    Publication date: November 22, 2012
    Applicant: NIHON DEMPA KOGYO CO., LTD.
    Inventors: Shunsuke UENO, Shingo KAWANISHI, Hiroki IWAI
  • 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: 20120180567
    Abstract: A technique for detecting external force applied to a piezoelectric plate is provided. A crystal plate is cantilever-supported in a container. Excitation electrodes are formed on an upper face and lower face, respectively, of the crystal plate. A movable electrode is formed on the lower face side. A fixed electrode is provided on a bottom portion of the container facing the movable electrode. The excitation electrode on the upper face side and the fixed electrode are connected to an oscillation circuit. When the crystal plate bends by external force applied, capacitance between. A direction of the movable electrode along a length direction of the crystal plate is set to 30° to 60°, relative to a face orthogonal to an intended direction of the external force. The movable electrode and fixed electrode changes, and this capacitance change and a deformation of the crystal circuit.
    Type: Application
    Filed: January 10, 2012
    Publication date: July 19, 2012
    Applicant: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Mitsuaki KOYAMA, Takeru MUTOH, Hiroki IWAI
  • Patent number: 8174171
    Abstract: An exemplary tuning-fork type piezoelectric vibrating piece has at least a pair of vibrating arms extending from one end of a base portion in a certain longitudinal direction (e.g., Y-direction). Supporting arms extend from respective side edges of the base, outboard of the vibrating arms in the certain direction. The supporting arms have respective mounting regions near their distal tips. Each supporting arm progressively narrows from its proximal end, coupled to the respective side edge of the base, to its respective mounting region. The progressive narrowing can be via one or more constrictions along the length of the supporting arm.
    Type: Grant
    Filed: September 15, 2009
    Date of Patent: May 8, 2012
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Hiroki Iwai