Patents by Inventor Masao Tokunaga

Masao Tokunaga 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: 11316403
    Abstract: An electric motor system includes a rotary shaft having an axis line displaceable relative to a rotation center, a magnetic bearing for supporting the rotary shaft, a permanent magnet mounted on the rotary shaft and having a plurality of magnetic poles arranged in a circumferential direction around the axis line of the rotary shaft, three detection elements arranged in the circumferential direction around the rotation center for detecting a magnetic flux generated from the permanent magnet, and a coordinate detection section for determining coordinates of the axis line of the rotary shaft based on output values of two detection elements selected out of the three detection elements in accordance with a rotation angle of the rotary shaft.
    Type: Grant
    Filed: July 13, 2017
    Date of Patent: April 26, 2022
    Assignee: DENSO CORPORATION
    Inventors: Masao Tokunaga, Masanori Yasuda, Koji Ito
  • Publication number: 20210336507
    Abstract: An electric motor system includes a rotary shaft having an axis line displaceable relative to a rotation center, a magnetic bearing for supporting the rotary shaft, a permanent magnet mounted on the rotary shaft and having a plurality of magnetic poles arranged in a circumferential direction around the axis line of the rotary shaft, three detection elements arranged in the circumferential direction around the rotation center for detecting a magnetic flux generated from the permanent magnet, and a coordinate detection section for determining coordinates of the axis line of the rotary shaft based on output values of two detection elements selected out of the three detection elements in accordance with a rotation angle of the rotary shaft.
    Type: Application
    Filed: July 13, 2017
    Publication date: October 28, 2021
    Inventors: Masao TOKUNAGA, Masanori YASUDA, Koji ITO
  • Patent number: 10958133
    Abstract: In an electric motor, a magnetic bearing generates an electromagnetic force between multiple permanent magnets and a coil and rotatably supports an other side of a rotation shaft in an axis line direction. The rotation shaft is configured to be capable of being inclined with a rotation center line using a bearing side of the rotation shaft as a fulcrum. An electronic control device controls a current that flows to the coil such that an axis line of the rotation shaft approaches the rotation center line due to a supporting force which is the electromagnetic force between the multiple permanent magnets and the coil. Accordingly, the rotation shaft is rotatably supported to be freely rotatable by a magnetic bearing and the bearing.
    Type: Grant
    Filed: October 29, 2015
    Date of Patent: March 23, 2021
    Assignees: DENSO CORPORATION, SOKEN, INC., National University Corporation Shizuoka University
    Inventors: Koji Ito, Masanori Yasuda, Shinji Makita, Jun Yamaoka, Masao Tokunaga, Etsuro Yoshino, Junichi Asama
  • Publication number: 20170324304
    Abstract: In an electric motor, a magnetic bearing generates an electromagnetic force between multiple permanent magnets and a coil and rotatably supports an other side of a rotation shaft in an axis line direction. The rotation shaft is configured to be capable of being inclined with a rotation center line using a bearing side of the rotation shaft as a fulcrum. An electronic control device controls a current that flows to the coil such that an axis line of the rotation shaft approaches the rotation center line due to a supporting force which is the electromagnetic force between the multiple permanent magnets and the coil. Accordingly, the rotation shaft is rotatably supported to be freely rotatable by a magnetic bearing and the bearing.
    Type: Application
    Filed: October 29, 2015
    Publication date: November 9, 2017
    Inventors: Koji ITO, Masanori YASUDA, Shinji MAKITA, Jun YAMAOKA, Masao TOKUNAGA, Etsuro YOSHINO, Junichi ASAMA
  • Patent number: 8766566
    Abstract: A battery temperature rise causing system has a converting unit for converting voltage of electric power held in one of a rechargeable battery and an accumulator and applies the converted voltage to the other one, and a control unit controlling the converting unit to alternately perform first transfer of electric power from the battery to the accumulator and second transfer of electric power from the accumulator to the battery while changing the first transfer for the second transfer each time the battery voltage reaches a lower limit and changing the second transfer for the first transfer each time the battery voltage reaches an upper limit, and to increase temperature of the battery due to heat generated by electric current flowing through the battery during the electric power transfer.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: July 1, 2014
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Hiroyasu Baba, Kunio Iritani, Masao Tokunaga
  • Publication number: 20120153877
    Abstract: A battery temperature rise causing system has a converting unit for converting voltage of electric power held in one of a rechargeable battery and a capacitor and applies the converted voltage to the other one, and a control unit controlling the converting unit to alternately perform first transfer of electric power from the battery to the capacitor and second transfer of electric power from the capacitor to the battery while changing the first transfer for the second transfer each time the battery voltage reaches a lower limit and changing the second transfer for the first transfer each time the battery voltage reaches an upper limit, and to increase temperature of the battery due to heat generated by electric current flowing through the battery during the electric power transfer.
    Type: Application
    Filed: December 20, 2011
    Publication date: June 21, 2012
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Hiroyasu BABA, Kunio IRITANI, Masao TOKUNAGA
  • Patent number: 7089809
    Abstract: A torque sensor has a torsion bar coaxially in alignment with input and output shafts, a ring shaped magnet fixed to an axial end of the input shaft, a pair of magnetic yokes fixed to an axial end of the output shaft, and a magnetic sensor for detecting magnetic flux density generated between the pair of magnetic yokes. Each of the magnetic yokes is provided with claws, which are circumferentially spaced at constant intervals, and whose number is equal to that of each of N and S poles alternately arranged circumferentially in the magnet. Each, center of the claws coincides with a boundary between immediately adjacent N and S poles of the magnet, when the torsion bar is not twisted. The magnetic sensor is inserted into an axial gap between the pair of magnetic yokes without contacting the magnetic yokes.
    Type: Grant
    Filed: February 23, 2006
    Date of Patent: August 15, 2006
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Naoki Nakane, Kiyoshi Sugimura, Shigetoshi Fukaya, Masao Tokunaga, Kenji Takeda
  • Publication number: 20060160063
    Abstract: The present invention relates to a method of screening a physiologically active substance, comprising the steps of (1) contacting a transformed yeast with a test sample, wherein the transformed yeast is capable of expressing a heterogeneous protein, and shows a change in a growing state in an expression state of the protein as compared to that in a non-expression state of the protein; (2) culturing the yeast under conditions that the protein is capable of being expressed; and (3) measuring the growing state of the yeast, wherein the physiologically active substance is judged to be present in the test sample in a case where the growth of the yeast is lowered or improved in the presence of the test sample as compared to that in the absence of the test sample as a control; an yeast to be used in the method; a physiologically active substance obtainable by the method of screening as defined above; and a kit for screening a physiologically active substance, comprising the yeast as defined above.
    Type: Application
    Filed: September 5, 2003
    Publication date: July 20, 2006
    Inventors: Iwao Katsuyama, Tsutomu Arakawa, Masao Tokunaga, Tadashi Yamamoto
  • Publication number: 20060137474
    Abstract: A torque sensor has a torsion bar coaxially in alignment with input and output shafts, a ring shaped magnet fixed to an axial end of the input shaft, a pair of magnetic yokes fixed to an axial end of the output shaft, and a magnetic sensor for detecting magnetic flux density generated between the pair of magnetic yokes. Each of the magnetic yokes is provided with claws, which are circumferentially spaced at constant intervals, and whose number is equal to that of each of N and S poles alternately arranged circumferentially in the magnet. Each, center of the claws coincides with a boundary between immediately adjacent N and S poles of the magnet, when the torsion bar is not twisted. The magnetic sensor is inserted into an axial gap between the pair of magnetic yokes without contacting the magnetic yokes.
    Type: Application
    Filed: February 23, 2006
    Publication date: June 29, 2006
    Inventors: Naoki Nakane, Kiyoshi Sugimura, Shigetoshi Fukaya, Masao Tokunaga, Kenji Takeda
  • Patent number: 7047824
    Abstract: A torque sensor has a torsion bar coaxially in alignment with input and output shafts, a ring shaped magnet fixed to an axial end of the input shaft, a pair of magnetic yokes fixed to an axial end of the output shaft, and a magnetic sensor for detecting magnetic flux density generated between the pair of magnetic yokes. Each of the magnetic yokes is provided with claws, which are circumferentially spaced at constant intervals, and whose number is equal to that of each of N and S poles alternately arranged circumferentially in the magnet. Each center of the claws coincides with a boundary between immediately adjacent N and S poles of the magnet, when the torsion bar is not twisted. The magnetic sensor is inserted into an axial gap between the pair of magnetic yokes without contacting the magnetic yokes.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: May 23, 2006
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Naoki Nakane, Kiyoshi Sugimura, Shigetoshi Fukaya, Masao Tokunaga, Kenji Takeda
  • Patent number: 7019516
    Abstract: A magnetic sensor unit includes an actuator motor and a magnetic position sensor. The actuator motor has a magnetic circuit including motor magnets. The magnetic position sensor includes a sensor magnet and a hall element for detecting magnetic flux. Magnet clearances are formed between the motor magnets. The hall element is disposed outside of the motor to detect the magnetic flux in a direction penetrating through the magnet clearances, and which is perpendicular to a direction from one of the motor magnets to the other. In this disposition of the hall element, it is restricted that the hall element detects leaking magnetic flux from the motor magnets.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: March 28, 2006
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Masao Tokunaga, Kenji Takeda, Tomomitsu Kamiya
  • Patent number: 6880411
    Abstract: A torque sensor has a torsion bar coaxially in alignment with input and output shafts, a ring shaped magnet fixed to an axial end of the input shaft, a pair of magnetic yokes fixed to an axial end of the output shaft, and a magnetic sensor for detecting magnetic flux density generated between the pair of magnetic yokes. Each of the magnetic yokes is provided with claws, which are circumferentially spaced at constant intervals, and whose number is equal to that of each of N and S poles alternately arranged circumferentially in the magnet. Each center of the claws coincides with a boundary between immediately adjacent N and S poles of the magnet, when the torsion bar is not twisted. The magnetic sensor is inserted into an axial gap between the pair of magnetic yokes without contacting the magnetic yokes.
    Type: Grant
    Filed: May 20, 2002
    Date of Patent: April 19, 2005
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Naoki Nakane, Kiyoshi Sugimura, Shiget shi Fukaya, Masao Tokunaga, Kenji Takeda
  • Patent number: 6867583
    Abstract: A displacement sensor precisely detects displacement of a moving body in a rectilinear movement direction even if the moving body rotates. The sensor includes a detector and a magnet. The cross sectional area of the permanent magnet in a plane perpendicular to an axis, which extends in the rectilinear movement direction, varies in the direction of movement. The permanent magnet is magnetized in the rectilinear movement direction. The detector is located so that magnetic flux passes through a detection face of the detector substantially perpendicularly.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: March 15, 2005
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Akitoshi Mizutani, Kenji Takeda, Masao Tokunaga, Tsutomu Nakamura, Keiichi Yasuda, Kimio Uchida, Hiroshi Takeyama, Tetsuo Hariu
  • Patent number: 6765631
    Abstract: A rain sensor includes an amplifier circuit that amplifies an output voltage from a photodiode and then provides this voltage signal to a CPU. The amplifier circuit conducts an offset amplification. The output voltage from the amplifier circuit is controlled to be at a predetermined level, for example, 3.0V, and the CPU detects rainfall based on the drop in the output voltage from the predetermined level, 3.0V. Then it becomes possible to improve sensor sensitivity, maintain a small sensor size, and a low manufacturing cost.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: July 20, 2004
    Assignee: Denso Corporation
    Inventors: Junichi Ishikawa, Masao Tokunaga
  • Publication number: 20040000902
    Abstract: A magnetic sensor unit includes an actuator motor and a magnetic position sensor. The actuator motor has a magnetic circuit including motor magnets. The magnetic position sensor includes a sensor magnet and a hall element for detecting magnetic flux. Magnet clearances are formed between the motor magnets. The hall element is disposed outside of the motor to detect the magnetic flux in a direction penetrating through the magnet clearances, and which is perpendicular to a direction from one of the motor magnets to the other. In this disposition of the hall element, it is restricted that the hall element detects leaking magnetic flux from the motor magnets.
    Type: Application
    Filed: June 11, 2003
    Publication date: January 1, 2004
    Inventors: Masao Tokunaga, Kenji Takeda, Tomomitsu Kamiya
  • Publication number: 20030209087
    Abstract: A torque sensor has a torsion bar coaxially in alignment with input and output shafts, a ring shaped magnet fixed to an axial end of the input shaft, a pair of magnetic yokes fixed to an axial end of the output shaft, and a magnetic sensor for detecting magnetic flux density generated between the pair of magnetic yokes. Each of the magnetic yokes is provided with claws, which are circumferentially spaced at constant intervals, and whose number is equal to that of each of N and S poles alternately arranged circumferentially in the magnet. Each center of the claws coincides with a boundary between immediately adjacent N and S poles of the magnet, when the torsion bar is not twisted. The magnetic sensor is inserted into an axial gap between the pair of magnetic yokes without contacting the magnetic yokes.
    Type: Application
    Filed: June 9, 2003
    Publication date: November 13, 2003
    Inventors: Naoki Nakane, Kiyoshi Sugimura, Shigetoshi Fukaya, Masao Tokunaga, Kenji Takeda
  • Patent number: 6627910
    Abstract: A precipitation sensor has a prism bonded to a front windshield, a beam transmitter, and a beam receiver. The prism has an entry-side prism wall, a connection wall, and an exit-side prism wall. The entry-side prism wall of the prism parallelizes light transmitted from the beam transmitter by refracting them on a convex lens face. The parallelized light is reflected from a parabolic outer face of the prism wall toward the inner face of the windshield. The parallel beams reflected from the inner face of the front windshield are reflected from a parabolic outer face of the exit-side prism wall and then focused on the beam receiver through a convex lens face of the prism wall. The convex shapes of the lens faces form arcs, the centers of which are aligned with the beam transmitter and the beam receiver, respectively.
    Type: Grant
    Filed: April 1, 2002
    Date of Patent: September 30, 2003
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Hirotsugu Ishino, Masao Tokunaga
  • Patent number: 6617813
    Abstract: A raindrop sensor detects an amount of raindrops landed on a window glass and outputs a measurement signal to a microcomputer. The microcomputer calculates an average amount of raindrops by averaging a predetermined number of the latest measurements. The microcomputer calculates an interval time for the wiper based on the calculated average amount of raindrops. At this time, when the calculated average amount of raindrops deviates from a predetermined reference value, the microcomputer calculates the average amount of raindrops using a smaller number of the latest measurements.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: September 9, 2003
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Taiji Morishita, Masao Tokunaga
  • Publication number: 20030094941
    Abstract: A displacement sensor precisely detects displacement of a moving body in a rectilinear movement direction even if the moving body rotates. The sensor includes a detector and a magnet. The cross sectional area of the permanent magnet in a plane perpendicular to an axis, which extends in the rectilinear movement direction, varies in the direction of movement. The permanent magnet is magnetized in the rectilinear movement direction. The detector is located so that magnetic flux passes through a detection face of the detector substantially perpendicularly.
    Type: Application
    Filed: November 13, 2002
    Publication date: May 22, 2003
    Inventors: Akitoshi Mizutani, Kenji Takeda, Masao Tokunaga, Tsutomu Nakamura, Keiichi Yasuda, Kimio Uchida, Hiroshi Takeyama, Tetsuo Hariu
  • Publication number: 20030029237
    Abstract: A rain sensor includes an amplifier circuit that amplifies an output voltage from a photodiode and then provides this voltage signal to a CPU. The amplifier circuit conducts an offset amplification. The output voltage from the amplifier circuit is controlled to be at a predetermined level, for example, 3.0V, and the CPU detects rainfall based on the drop in the output voltage from the predetermined level, 3.0V. Then it becomes possible to improve sensor sensitivity, maintain a small sensor size, and a low manufacturing cost.
    Type: Application
    Filed: August 8, 2002
    Publication date: February 13, 2003
    Inventors: Junichi Ishikawa, Masao Tokunaga