Patents by Inventor Kenichi Morokuma

Kenichi Morokuma 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: 11938814
    Abstract: A driving assistance device enables a driver who manually performs an accelerator operation and a steering operation to easily retain an accelerator operation state in a constant state. A driving assistance device includes a manually operable accelerator operation unit in the vicinity of a steering wheel provided in front of a driver seat in a vehicle cabin. The accelerator operation unit is operable in a state where the steering wheel is gripped and an operation reaction force of the accelerator operation unit exhibits an inflection point POI at which the operation reaction force rapidly becomes large in response to an increase in an operation amount of the accelerator operation unit.
    Type: Grant
    Filed: December 20, 2021
    Date of Patent: March 26, 2024
    Assignee: MAZDA MOTOR CORPORATION
    Inventors: Yutaka Sakuragi, Tomoya Yamamoto, Kenichi Nakamoto, Yasuyuki Tonohara, Yu Morokuma, Katsuhisa Maedo
  • Publication number: 20230198373
    Abstract: A drive adjustment circuit for a power semiconductor element includes a differentiating circuit to differentiate a gate voltage of a power semiconductor element, a power supply to generate a comparison reference voltage, a comparator having a first input terminal connected to the differentiating circuit and a second input terminal receiving the comparison reference voltage, and a voltage adjusting circuit to adjust a gate voltage of the power semiconductor element based on an output of the comparator.
    Type: Application
    Filed: July 14, 2020
    Publication date: June 22, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kenichi MOROKUMA, Takuya SAKAI
  • Publication number: 20230179196
    Abstract: A classification circuit generates first information for classifying an operating state of a power semiconductor element into one of a plurality of predetermined operating regions. A selector circuit generates second information for selecting a plurality of modes with different switching speeds, based on a user input. A characteristic control circuit stores a drive adjustment signal in advance for each of combinations of the operating regions and the modes and outputs the drive adjustment signal in a combination of one operating region and one mode that is selected in accordance with the first information and the second information. A gate drive circuit charges/discharges a gate at a charge rate and a discharge rate variably set in accordance with the drive adjustment signal from the characteristic control circuit, at the time of on/off of the power semiconductor element.
    Type: Application
    Filed: June 1, 2020
    Publication date: June 8, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shotaro YAMAMOTO, Kenichi MOROKUMA, Yoshiko TAMADA
  • Patent number: 11601054
    Abstract: A power semiconductor device protection circuit includes: a drive circuit that drives a power semiconductor device; a current detector which includes a first resistor and an inductor connected in parallel; and a detection circuit that detects a short-circuit condition of the power semiconductor device. One end of the first resistor and one end of the inductor are connected to one terminal of the power semiconductor device. The detection circuit detects the short-circuit condition of the power semiconductor device by comparing a voltage of the one terminal of the power semiconductor device, which changes as a function of current flow through the first resistor and the inductor, with a short-circuit detection voltage. A reference potential of the drive circuit is connected to the other end of the first resistor and the other end of the inductor.
    Type: Grant
    Filed: March 12, 2019
    Date of Patent: March 7, 2023
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kenichi Morokuma, Takuya Sakai
  • Patent number: 10998832
    Abstract: A first circuit generates and outputs a transmission signal to a first end and a second end of a first coil in response to variation in logical value of an input first signal. A detection circuit detects a voltage signal generated at each of a first end and a second end and outputs a second signal which reflects the first signal based on a result of detection. A control circuit controls a voltage to be applied across opposing ends of each of a first diode and a second diode of a first rectifier circuit and a voltage to be applied to opposing ends of each of a third diode and a fourth diode of a second rectifier circuit.
    Type: Grant
    Filed: May 18, 2017
    Date of Patent: May 4, 2021
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kenichi Morokuma, Motoki Imanishi
  • Publication number: 20210028702
    Abstract: A power semiconductor device protection circuit includes: a drive circuit that drives a power semiconductor device; a current detector which includes a first resistor and an inductor connected in parallel; and a detection circuit that detects a short-circuit condition of the power semiconductor device. One end of the first resistor and one end of the inductor are connected to one terminal of the power semiconductor device. The detection circuit detects the short-circuit condition of the power semiconductor device by comparing a voltage of the one terminal of the power semiconductor device, which changes as a function of current flow through the first resistor and the inductor, with a short-circuit detection voltage. A reference potential of the drive circuit is connected to the other end of the first resistor and the other end of the inductor.
    Type: Application
    Filed: March 12, 2019
    Publication date: January 28, 2021
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kenichi MOROKUMA, Takuya SAKAI
  • Publication number: 20190222107
    Abstract: A first circuit generates and outputs a transmission signal to a first end and a second end of a first coil in response to variation in logical value of an input first signal. A detection circuit detects a voltage signal generated at each of a first end and a second end and outputs a second signal which reflects the first signal based on a result of detection. A control circuit controls a voltage to be applied across opposing ends of each of a first diode and a second diode of a first rectifier circuit and a voltage to be applied to opposing ends of each of a third diode and a fourth diode of a second rectifier circuit.
    Type: Application
    Filed: May 18, 2017
    Publication date: July 18, 2019
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kenichi MOROKUMA, Motoki IMANISHI
  • Patent number: 10298226
    Abstract: A signal transmission device relating to a technique disclosed in the specification of the present application includes: an isolation transformer; an input-side circuit connected to an input side of the isolation transformer; and an output-side circuit connected to an output side of the isolation transformer. The output-side circuit includes a first differential circuit having a first input and a second input connected to the first terminal and the second terminal respectively. A reference potential of the first differential circuit is connected to the second terminal.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: May 21, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Motoki Imanishi, Kenichi Morokuma
  • Patent number: 10199340
    Abstract: A signal transmission insulating device includes: a first coil; a second coil opposing the first coil to form a transformer together with the first coil; a first insulating film provided between the opposing first coil and second coil and made of a first dielectric material; a second insulating film surrounding the first coil and made of a second dielectric material having a lower resistivity or a higher permittivity than the first dielectric material; and a third insulating film surrounding the second coil and made of a third dielectric material having a lower resistivity or a higher permittivity than the first dielectric material.
    Type: Grant
    Filed: August 19, 2015
    Date of Patent: February 5, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Suga, Takao Tsurimoto, Hiroki Shiota, Kenichi Morokuma, Shoichi Orita, Fumitaka Tametani, Takahiro Inoue, Shiori Uota
  • Patent number: 10171070
    Abstract: A first circuit outputs transmission signals that change between “H” and “L” in a period of an oscillation signal in addition to a transition time of an input signal when it changes to “H” or “L”. Control protection elements invalidate induced voltage signals obtained from transformers for first and second mask periods in response to transmission signals. Buffer circuits and Schmitt circuits generate a first signal and a second signal, each indicating “H” for a relatively long period, on the basis of “H” of the induced voltage signals. A control circuit invalidates the first signal and the second signal when both the first signal and the second signal indicate “H”.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: January 1, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Morokuma, Jun Tomisawa, Tetsuya Uchida, Shoichi Orita
  • Patent number: 10014856
    Abstract: This invention, is concerning a signal voltage device, in which transformers 22a, 22b and a reception circuit 24 are formed on the same chip, and accordingly, no ESD protective element connected to a transformer connection terminal of the reception circuit 24 is required, and negative pulses generated in reception-side inductors 11 can be used in signal transmission. Signal transmission using both positive pulses and negative pulses is made possible as a result, and a stable signal transmission operation can be carried out even in a case where delay time varies in a signal detection circuit. Further, a reception circuit of low power consumption can be configured by using a single-ended Schmitt trigger circuit 14 in the signal detection circuit.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: July 3, 2018
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Tetsuya Uchida, Kenichi Morokuma
  • Publication number: 20180175847
    Abstract: A first circuit outputs transmission signals that change between “H” and “L” in a period of an oscillation signal in addition to a transition time of an input signal when it changes to “H” or “L”. Control protection elements invalidate induced voltage signals obtained from transformers for first and second mask periods in response to transmission signals. Buffer circuits and Schmitt circuits generate a first signal and a second signal, each indicating “H” for a relatively long period, on the basis of “H” of the induced voltage signals. A control circuit invalidates the first signal and the second signal when both the first signal and the second signal indicate “H”.
    Type: Application
    Filed: May 12, 2016
    Publication date: June 21, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kenichi MOROKUMA, Jun TOMISAWA, Tetsuya UCHIDA, Shoichi ORITA
  • Publication number: 20180013419
    Abstract: A signal transmission device relating to a technique disclosed in the specification of the present application includes: an isolation transformer; an input-side circuit connected to an input side of the isolation transformer; and an output-side circuit connected to an output side of the isolation transformer. The output-side circuit includes a first differential circuit having a first input and a second input connected to the first terminal and the second terminal respectively. A reference potential of the first differential circuit is connected to the second terminal.
    Type: Application
    Filed: March 2, 2017
    Publication date: January 11, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Motoki IMANISHI, Kenichi MOROKUMA
  • Publication number: 20180013424
    Abstract: This invention, is concerning a signal voltage device, in which transformers 22a, 22b and a reception circuit 24 are formed on the same chip, and accordingly, no ESD protective element connected to a transformer connection terminal of the reception circuit 24 is required, and negative pulses generated in reception-side inductors 11 can be used in signal transmission. Signal transmission using both positive pulses and negative pulses is made possible as a result, and a stable signal transmission operation can be carried out even in a case where delay time varies in a signal detection circuit. Further, a reception circuit of low power consumption can be configured by using a single-ended Schmitt trigger circuit 14 in the signal detection circuit.
    Type: Application
    Filed: January 12, 2016
    Publication date: January 11, 2018
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Tetsuya UCHIDA, Kenichi MOROKUMA
  • Publication number: 20170278811
    Abstract: A signal transmission insulating device includes: a first coil; a second coil opposing the first coil to form a transformer together with the first coil; a first insulating film provided between the opposing first coil and second coil and made of a first dielectric material; a second insulating film surrounding the first coil and made of a second dielectric material having a lower resistivity or a higher permittivity than the first dielectric material; and a third insulating film surrounding the second coil and made of a third dielectric material having a lower resistivity or a higher permittivity than the first dielectric material.
    Type: Application
    Filed: August 19, 2015
    Publication date: September 28, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kenichi SUGA, Takao TSURIMOTO, Hiroki SHIOTA, Kenichi MOROKUMA, Shoichi ORITA, Fumitaka TAMETANI, Takahiro INOUE, Shiori UOTA
  • Patent number: 9502954
    Abstract: A signal transmission circuit includes, in each of a first circuit connected to a first coil of an insulating transformer and a second circuit connected to a second coil of the insulating transformer, a transmitting circuit, a receiving circuit, a coil-side switching circuit, an input/output-side switching circuit, an abnormality detection circuit, a delay circuit, and a direction control section. In the signal transmission circuit, the direction control section controls the switching circuit to switch a signal direction between input and output, and the switching circuit switches between transmission and reception. The delay circuit delays a received signal and returns the resultant signal to the transmitting side, and the abnormality detection circuit detects abnormality to perform self-diagnosis.
    Type: Grant
    Filed: October 28, 2013
    Date of Patent: November 22, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Morokuma, Jun Tomisawa, Tetsuya Uchida, Kazuyasu Nishikawa
  • Patent number: 9396871
    Abstract: A transmitter circuit feeds to a transmitter coil, every time transmission data changes in logical value, a current signal in pulse form having a positive or negative polarity that is alternately inverted in response to each change in logical value; and a receiver circuit inputs induction voltage signals each being double pulses having both positive and negative polarities, which have been induced in a receiver coil by the current signal fed to the transmitter coil, to demodulate the transmission data. The receiver circuit includes: an amplifier that amplifies the induction voltage signals of double pulses induced in the receiver coil; and a signal generating unit that, when detecting first single pulses in the induction voltage signals of double pulses amplified by the amplifier, sets up an insensitive period for second single pulses therein, to generate an output signal corresponding to the transmission data, based solely on the first single pulses.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: July 19, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Morokuma, Jun Tomisawa, Kazuyasu Nishikawa
  • Publication number: 20160020686
    Abstract: A signal transmission circuit (1000) includes, in each of a first circuit (100) connected to a first coil (110) of an insulating transformer (10) and a second circuit (200) connected to a second coil (210) of the insulating transformer (10), a transmitting circuit (120, 220), a receiving circuit (130, 230), a coil-side switching circuit (140, 240), an input/output-side switching circuit (150, 250), an abnormality detection circuit (160, 260), a delay circuit (170, 270), and a direction control section (180, 280). In the signal transmission circuit (1000), the direction control section (180, 280) controls the switching circuit (150, 250) to switch a signal direction between input and output, and the switching circuit (140, 240) switches between transmission and reception. The delay circuit (170, 270) delays a received signal and returns the resultant signal to the transmitting side, and the abnormality detection circuit (160, 260) detects abnormality to perform self-diagnosis.
    Type: Application
    Filed: October 28, 2013
    Publication date: January 21, 2016
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kenichi MOROKUMA, Jun TOMISAWA, Tetsuya UCHIDA, Kzauyasu NISHIKAWA
  • Patent number: 9195253
    Abstract: A signal transmission circuit includes an isolation circuit, first and second grounded gate circuits, first and second MOS transistors, and a comparator. The isolation circuit such as a thin-film transformer outputs complementary first and second output signals, based on an input signal. The first and second grounded gate circuits receive and amplify the first and second output signals, respectively. The first and second MOS transistors are connected between a power supply node and the first and second grounded gate circuits, respectively, for adjusting the first and second output signals. The comparator compares output from the first grounded gate circuit with output from the second grounded gate circuit.
    Type: Grant
    Filed: April 18, 2012
    Date of Patent: November 24, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Morokuma, Jun Tomisawa
  • Publication number: 20150248966
    Abstract: A transmitter circuit feeds to a transmitter coil, every time transmission data changes in logical value, a current signal in pulse form having a positive or negative polarity that is alternately inverted in response to each change in logical value; and a receiver circuit inputs induction voltage signals each being double pulses having both positive and negative polarities, which have been induced in a receiver coil by the current signal fed to the transmitter coil, to demodulate the transmission data. The receiver circuit includes: an amplifier that amplifies the induction voltage signals of double pulses induced in the receiver coil; and a signal generating unit that, when detecting first single pulses in the induction voltage signals of double pulses amplified by the amplifier, sets up an insensitive period for second single pulses therein, to generate an output signal corresponding to the transmission data, based solely on the first single pulses.
    Type: Application
    Filed: December 4, 2012
    Publication date: September 3, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kenichi Morokuma, Jun Tomisawa, Kazuyasu Nishikawa