Patents by Inventor Mitsuaki Hirakawa

Mitsuaki Hirakawa 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: 9327658
    Abstract: A power conversion device in an electric vehicle that uses a short-circuit capacitor and is capable of detecting a short circuit of the capacitor by using a simple structure. The power conversion device includes an inductor connected on a main battery side with a switching member provided between the inductor and a power line. The power line connects a first capacitor and a second capacitor as well as an electric load in parallel. A controller is provided for controlling the on/off of the switching member. The first capacitor and the second capacitor are each a small capacitor configured to be short-circuited upon application of an excess voltage. The power conversion device is provided with a detection member for detecting a short circuit of any one of the first capacitor and the second capacitor. The detection member is connected in series to the first capacitor and the second capacitor.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: May 3, 2016
    Assignee: HONDA MOTOR CO., LTD.
    Inventors: Yasuto Watanabe, Mitsuaki Hirakawa
  • Patent number: 9252665
    Abstract: In a DC-DC converter control apparatus, it is configured to have a current sensor for detecting a current flowing through a positive electrode wire connecting the second common terminal with the positive electrode terminal of the high-voltage port and to control operations of the first and second switching elements based on the current detected by the current sensor. With this, it becomes possible to accurately detect the current of the windings and appropriately control the operation of the switching elements based on the detected currents without increasing the transformer in size.
    Type: Grant
    Filed: May 12, 2011
    Date of Patent: February 2, 2016
    Assignee: HONDA MOTOR CO., LTD.
    Inventors: Satoshi Hashino, Keigo Andoh, Mitsuaki Hirakawa
  • Patent number: 8664926
    Abstract: A DC-DC converter includes first and second capacitors connected in series, a switching part, and a control circuit part which includes a voltage difference calculating part for calculating a difference between voltages of the first and second capacitors, a duty ratio controller for controlling duty ratio of on- and OFF-durations to decrease the voltage difference of the first and second capacitors on the basis of the calculated difference. A power supplying system including the DC-DC converter controls balance between first and second capacitors in voltage on the basis of the powering/regenerating discriminating signal.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: March 4, 2014
    Assignee: Honda Motor Co., Ltd.
    Inventors: Somei Nakatomi, Yasuto Watanabe, Keigo Andoh, Mitsuaki Hirakawa
  • Patent number: 8659272
    Abstract: To provide a DC/DC converter capable of down-sizing magnetic components and varying boosting and bucking ratios, and a bidirectional boosting-bucking operations, a bidirectional boosting-bucking magnetic-field cancellation type of DC/DC converter (10) is provided which includes: a first voltage side port (P1), a second voltage side port (P2); a common reference terminal (CP), a smoothing capacitor (C1), four switching elements (SW1, SW2, SW3, SW4), an inductors (L1, L2), a magnetic-field cancellation type transformer T including a primary winding (L3) and a secondary winging (L4), four switching elements (SW5, SW6, SW7, SW8), and a smoothing capacitor (C2).
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: February 25, 2014
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yasuto Watanabe, Mitsuaki Hirakawa
  • Publication number: 20140001838
    Abstract: A power conversion device in an electric vehicle that uses a short-circuit capacitor and is capable of detecting a short circuit of the capacitor by using a simple structure. The power conversion device includes an inductor connected on a main battery side with a switching member provided between the inductor and a power line. The power line connects a first capacitor and a second capacitor as well as an electric load in parallel. A controller is provided for controlling the on/off of the switching member. The first capacitor and the second capacitor are each a small capacitor configured to be short-circuited upon application of an excess voltage. The power conversion device is provided with a detection member for detecting a short circuit of any one of the first capacitor and the second capacitor. The detection member is connected in series to the first capacitor and the second capacitor.
    Type: Application
    Filed: May 23, 2013
    Publication date: January 2, 2014
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Yasuto WATANABE, Mitsuaki HIRAKAWA
  • Patent number: 8481220
    Abstract: A fuel cell power supply includes a fuel cell voltage detection means which detects a terminal-to-terminal voltage of the fuel cell; an internal resistance calculation element configured to supply electric power from a battery to a motor via a second DC-DC converter and configured to calculates a resistance value of an internal resistance of the fuel cell on the basis of a detection voltage of the fuel cell in a state where a current output of the fuel cell is stopped, a detection voltage of a terminal-to-terminal voltage of the fuel cell in a state where the output current of the fuel cell is adjusted to a value, and the value; and a deterioration level determination element configured to determines a deterioration level of the fuel cell on the basis of a change in the resistance value of the internal resistance of the fuel cell.
    Type: Grant
    Filed: January 21, 2009
    Date of Patent: July 9, 2013
    Assignee: Honda Motor Co., Ltd.
    Inventors: Mitsuaki Hirakawa, Minoru Noguchi
  • Patent number: 8440338
    Abstract: A battery assembling body capable of preventing a temperature rise of a battery while preventing an inflow of foreign matters. The battery assembling body (12) includes a housing (15) which contains batteries (2a, 2b, 6), a side frame (17) which is used to detachably fit the housing (15) to a lower frame of a vehicle, a ventilation hole (18c) located upper part of the housing (15), and a ventilation space (24a, 24b) which is formed between the housing (15) and the batteries, and the ventilation space (24, 24b) is in communication with the ventilation hole (18c).
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: May 14, 2013
    Assignee: Honda Motor Co., Ltd.
    Inventors: Kazuo Sato, Eisuke Komazawa, Takeshi Fujino, Mitsuaki Hirakawa
  • Publication number: 20130069610
    Abstract: In a DC-DC converter control apparatus, it is configured to have a current sensor for detecting a current flowing through a positive electrode wire connecting the second common terminal with the positive electrode terminal of the high-voltage port and to control operations of the first and second switching elements based on the current detected by the current sensor. With this, it becomes possible to accurately detect the current of the windings and appropriately control the operation of the switching elements based on the detected currents without increasing the transformer in size.
    Type: Application
    Filed: May 12, 2011
    Publication date: March 21, 2013
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Satoshi Hashino, Keigo Andoh, Mitsuaki Hirakawa
  • Patent number: 8400250
    Abstract: A composite (combined type of) transformer includes: a transformer core including a plurality of transformer magnetic leg portions, a transformer magnetic leg portion, and a pair of transformer bases; a plurality of inductor cores each including an inductor magnetic leg portions, inductor outer magnetic leg portions, and a pair of inductor bases; and a plurality of windings wound around the transformer magnetic leg portion and the inductor magnetic leg portions. The windings are wound to generate magnetic fluxes in such directions as to be cancelled out in a magnetic closed circuit in the transformer core.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: March 19, 2013
    Assignee: Honda Motor Co., Ltd.
    Inventors: Masao Nagano, Satoshi Hashino, Mitsuaki Hirakawa
  • Patent number: 8325004
    Abstract: A composite transformer includes: a transformer core including transformer-core legs; inductor cores including inductor-core legs; windings wound around the transformer-core legs and the inductor-core legs; the transformer core includes a pair of transformer bases connected to both ends of each of the transformer-core legs, and allows formation of closed magnetic circuits in the transformer core; each of the inductor cores includes one of the inductor-core legs, an outer core leg, and a pair of inductor bases connected to both ends of the one of the inductor-core legs and both ends of the outer core leg, and allows formation of a closed magnetic circuit in each inductor core; and the windings are wound in such directions that the magnetic fluxes produced in the transformer-core legs cancel each other in the closed magnetic circuits in the transformer core whichever of the windings is energized.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: December 4, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventors: Masao Nagano, Satoshi Hashino, Mitsuaki Hirakawa
  • Patent number: 8228690
    Abstract: A DC-DC converter has a first-voltage-side port, a second-voltage-side port, and a third-voltage-side port, and performs, at different timings, an operation of boosting a first voltage to a third voltage and an operation of bucking a second voltage to the third voltage. A power supplying system includes a fuel cell, a secondary battery, an accessory system, the DC-DC converter, and another DC-DC converter connected between the fuel cell and a motor, and boosting the first voltage of the fuel cell to a fourth voltage to supply power to the motor through an inverter. The former DC-DC converter has the first-voltage-side port connected to the fuel cell, has the second-voltage-side port connected to the secondary battery, and has the third-voltage-side port connected to the accessory system.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: July 24, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yasuto Watanabe, Mitsuaki Hirakawa
  • Publication number: 20120134180
    Abstract: To provide a DC/DC converter capable of down-sizing magnetic components and varying boosting and bucking ratios, and a bidirectional boosting-bucking operations, a bidirectional boosting-bucking magnetic-field cancellation type of DC/DC converter (10) is provided which includes: a first voltage side port (P1), a second voltage side port (P2); a common reference terminal (CP), a smoothing capacitor (C1), four switching elements (SW1, SW2, SW3, SW4), an inductors (L1, L2), a magnetic-field cancellation type transformer T including a primary winding (L3) and a secondary winging (L4), four switching elements (SW5, SW6, SW7, SW8), and a smoothing capacitor (C2).
    Type: Application
    Filed: August 3, 2010
    Publication date: May 31, 2012
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Yasuto Watanabe, Mitsuaki Hirakawa
  • Patent number: 8184421
    Abstract: The objective of the present invention is to provide a power converter capable of not only boosting the voltage but also shutting-off the flowing current, by switching only the switch element. The power converter 1, comprises a first input-output portion 3, a second input-output portion 5, a first capacitor C1, a second capacitor C2 electrically connected with the first capacitor C1 in serial, a first current control block B1, a second current control block B2, a third current control block B3, a fourth current control block B4, and a switching controller 7 operable to switch certain current control blocks, wherein the current flowing direction is opposite to each other between a first current control element B1a (B2a, B3a, B4a) and a second current control element B1b (B2b, B3b, B4b) which compose the current control block B1 (B2, B3, B4).
    Type: Grant
    Filed: May 21, 2009
    Date of Patent: May 22, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yasuto Watanabe, Satoshi Hashino, Mitsuaki Hirakawa
  • Patent number: 8138744
    Abstract: Combined type transformer includes: a transformer core; first and second coils provided with respect to the transformer core; first and second inductor cores provided around the first coil; and third and fourth inductor cores provided around the second coil. The transformer core and the first and second coils constitute a transformer, the first coil and the first and second inductor cores constitute a first inductor, and the second coil and the third and fourth inductor cores constitute a second inductor.
    Type: Grant
    Filed: August 4, 2010
    Date of Patent: March 20, 2012
    Assignees: Honda Motor Co., Ltd.
    Inventors: Masao Nagano, Mitsuaki Hirakawa, Toshihisa Shimizu
  • Publication number: 20120062349
    Abstract: A composite (combined type of) transformer includes: a transformer core including a plurality of transformer magnetic leg portions, a transformer magnetic leg portion, and a pair of transformer bases; a plurality of inductor cores each including an inductor magnetic leg portions, inductor outer magnetic leg portions, and a pair of inductor bases; and a plurality of windings wound around the transformer magnetic leg portion and the inductor magnetic leg portions. The windings are wound to generate magnetic fluxes in such directions as to be cancelled out in a magnetic closed circuit in the transformer core.
    Type: Application
    Filed: September 2, 2011
    Publication date: March 15, 2012
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Masao NAGANO, Satoshi HASHINO, Mitsuaki HIRAKAWA
  • Publication number: 20120056704
    Abstract: A composite transformer includes: a transformer core including transformer-core legs; inductor cores including inductor-core legs; windings wound around the transformer-core legs and the inductor-core legs; the transformer core includes a pair of transformer bases connected to both ends of each of the transformer-core legs, and allows formation of closed magnetic circuits in the transformer core; each of the inductor cores includes one of the inductor-core legs, an outer core leg, and a pair of inductor bases connected to both ends of the one of the inductor-core legs and both ends of the outer core leg, and allows formation of a closed magnetic circuit in each inductor core; and the windings are wound in such directions that the magnetic fluxes produced in the transformer-core legs cancel each other in the closed magnetic circuits in the transformer core whichever of the windings is energized.
    Type: Application
    Filed: September 2, 2011
    Publication date: March 8, 2012
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Masao NAGANO, Satoshi HASHINO, Mitsuaki HIRAKAWA
  • Patent number: 8106635
    Abstract: A power converter includes an input unit, an output unit, first and second capacitors connected in series, a first electric conduction control device, a second electric conduction control device, a third electric conduction control device, and a fourth electric conduction control device, and a control circuit for performing on/off control on those electric conduction control devices. The first electric conduction control device and the fourth electric conduction control device have a first path through which a current flowing between the input unit and the output unit is allowed to flow in one direction, and a second path which has a switch function of allowing the current flowing between the input unit and the output unit to flow through or shutting off such a current.
    Type: Grant
    Filed: August 7, 2009
    Date of Patent: January 31, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventors: Yasuto Watanabe, Satoshi Hashino, Mitsuaki Hirakawa
  • Patent number: 8097373
    Abstract: It is an object of the present invention to provide a fuel cell power supply device that can realize a reduction in size and improvement of durability of an accumulating unit while maintaining output performance that is applicable when large output is requested.
    Type: Grant
    Filed: November 26, 2008
    Date of Patent: January 17, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventors: Takeshi Fujino, Minoru Noguchi, Eisuke Komazawa, Mitsuaki Hirakawa
  • Patent number: 8084988
    Abstract: A power supply system includes a fuel cell, a capacitor connected in parallel to the fuel cell, a voltage boost means for boosting output voltages from the fuel cell and the capacitor to supply the electric motor with electric power resulting from the boosted voltages, a voltage control means for further boosting an output voltage from the voltage boost means, a secondary battery connected to the voltage control means, an external power source connecting means connected to the one end of the voltage boost means and in parallel with the fuel cell and for receiving supply of electric power from an external power source, and an electronic control unit which charges the secondary battery from the external power source by controlling step-up ratios of the voltage boost means and the voltage control means such that a voltage applied to the secondary battery during the charging becomes a desired voltage.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: December 27, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventors: Takeshi Fujino, Minoru Noguchi, Eisuke Komazawa, Mitsuaki Hirakawa
  • Publication number: 20110298427
    Abstract: In an apparatus for heating a battery of a vehicle, having an electric rotating machine and buck-boost converter between the battery and rotating machine to step up/down voltage outputted from the battery to be supplied to the rotating machine and step up/down voltage generated by the rotating machine to be supplied to the battery, it is configured to have a first capacitor interposed between wires connecting the battery to the converter, a second capacitor interposed between wires connecting the converter to the rotating machine, and a heating controller to control operation of the converter to generate current similar to rectangular wave current and input/output the current between the battery and the second capacitor through the first capacitor so as to heat the battery. With this, it becomes possible to efficiently heat the battery so that the battery can output expected power, without adversely affecting the size of the apparatus.
    Type: Application
    Filed: June 1, 2011
    Publication date: December 8, 2011
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Takuro UEMURA, Mitsuaki HIRAKAWA, Satoshi HASHINO