Patents by Inventor Kenji Nakajima

Kenji Nakajima 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: 20140292286
    Abstract: A control section is configured to, when it is detected that a voltage of a B-terminal of a power generator has exceeded a first predetermined voltage value, turn on all switching elements of a negative arm of a bridge circuit connected to one set of armature windings and turn off all switching elements of a positive arm, and reduce a field current flowing in a field winding. The control section is configured to thereafter turn off all the turned-on switching elements when a predetermined condition is satisfied.
    Type: Application
    Filed: December 15, 2011
    Publication date: October 2, 2014
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Mitsunori Tabata, Masato Mori, Kenji Nakajima, Kenichi Akita
  • Patent number: 8829863
    Abstract: A field winding type rotary electric machine includes: a controller; a field current integration portion provided in the controller to calculate an integral value by integrating an excessive field current exceeding a field current threshold; a field current limiting portion provided in the controller and carrying out limiting processing to limit a field current to or below a predetermined value when the integral value reaches an integral value threshold defined as a reference value at or above which the field current is limited; a controller power supply connection switch switched ON and OFF for power feeding to the controller; a controller power supply connection determination portion switching ON and OFF the controller power supply connection switch; and a power feeding ON state maintaining portion maintaining an ON state of the power feeding to the controller from start to end of the limiting processing by the field current limiting portion.
    Type: Grant
    Filed: December 16, 2011
    Date of Patent: September 9, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Akita, Kenji Nakajima, Masato Mori, Mitsunori Tabata
  • Patent number: 8818674
    Abstract: Provided is a vehicle behavior controller capable of stabilizing a behavior of a vehicle with a high response when an unstable state of the vehicle is judged. The vehicle behavior controller includes: a running state detecting unit for detecting a running state of the vehicle; an unstable state judging unit for judging the unstable state of the vehicle based on the running state; a motor generator connected to an engine of the vehicle, the motor generator operating as a power generator for using an output of a prime mover to generate power and an electric motor for assisting the output of the prime mover; and a control unit for controlling an operation of the motor generator based on r.p.m. of the motor generator, in which the control unit controls the operation of the motor generator to generate braking torque when the unstable state is judged.
    Type: Grant
    Filed: April 24, 2009
    Date of Patent: August 26, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Nakajima, Masato Mori, Kenichi Akita
  • Patent number: 8803818
    Abstract: An input apparatus includes, a display unit that causes a plurality of display screens on which images are to be displayed to display the images, a input detecting unit that detects a first input on a first display screen, a second input on the first display screen, and a third input on a second display screen, a position acquiring unit that acquires a first position, a second position and a third position, a start-position estimating unit that estimates a start position of an associated operation on the second display screen, and a continuity determining unit that determines whether the third input is the associated operation based upon the third position and the start position.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: August 12, 2014
    Assignee: Fujitsu Limited
    Inventors: Naomi Iwayama, Kenji Nakajima
  • Patent number: 8736234
    Abstract: A power converter control apparatus includes a power converter part having a bridge circuit formed of a switching element and a field circuit controlling conduction of a field winding in an AC generator, and a control apparatus part having a field current detector, a temperature detector detecting a temperature of a generator part, the power converter part, or the control apparatus part, a field current instruction computation portion computing a field current instruction value of the generator, a temperature rise suppression portion computing a generated current suppression value on the basis of an output of the temperature detector and computing a field current suppression value on the basis of the computed generated current suppression value, a field current instruction selection portion selecting the field current instruction value or the field current suppression value whichever is the smaller, and a field current control portion controlling a field current.
    Type: Grant
    Filed: October 11, 2011
    Date of Patent: May 27, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Nakajima, Masato Mori, Kenichi Akita, Mitsunori Tabata
  • Patent number: 8736235
    Abstract: A power-generation motor control system is a control system that controls a power-generation motor provided with an armature and a magnetic-field winding, and is characterized in that when the power-generation motor is operated as a motor, before a power source energizes the armature, a preliminary excitation current, with the value of which the induction voltage across the armature does not exceed the voltage of the power source, is applied to the magnetic-field winding in accordance with the rotation speed of the power-generation motor so that preliminary excitation of the power-generation motor is performed.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: May 27, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Mitsunori Tabata, Masato Mori, Kenji Nakajima, Kenichi Akita
  • Patent number: 8704400
    Abstract: A vehicle power converter including a plurality of switching elements having diodes connected thereto in parallel and constituting a multi-phase bridge circuit and a controller for conducting the switching element corresponding to each diode in synchronization with a conduction state of the diode concerned to perform synchronous rectification and is connected between a power generator-motor driven from the external to generate multi-phase AC power and DC equipment, further includes a load state detecting unit for detecting a load state of the power generator-motor when the multi-phase AC power occurs, wherein a shift from diode rectification to synchronous rectification or a shift from the synchronous rectification to the diode rectification is carried out in accordance with an output of the load state detecting unit.
    Type: Grant
    Filed: November 2, 2009
    Date of Patent: April 22, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Nakajima, Kenichi Akita, Masato Mori, Mitsunori Tabata, Katsuya Tsujimoto
  • Patent number: 8680796
    Abstract: To provide an upper limit of a generated voltage or generated torque, to thereby prevent the occurrence of an overvoltage or excessive torque during power generation, a control selection section (308) chooses and outputs a minimum value between a control output of a generated voltage control section (306) for controlling a field current so that a B-terminal voltage of a polyphase AC generator-motor coincides with a generated voltage command and a control output of a generated torque control section (307) for controlling, based on the B-terminal voltage and a rotation speed, the field current so that generated torque of the polyphase AC generator-motor coincides with a generated torque command.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: March 25, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Nakajima, Masato Mori, Kenichi Akita, Mitsunori Tabata
  • Patent number: 8680819
    Abstract: A field winding type rotary electric machine includes a motor generator; a field current detection unit; a field current control unit which controls a field current; a field current limiting determination section which calculates a field current integration value and determines whether or not the field current integration value reaches a predetermined field current integration threshold value; and a field current limiting command section which, when it is determined that the field current integration value reaches the predetermined field current integration threshold value, outputs a command which sets the field current to be lower than or equal to a predetermined field current limiting value to the field current control unit during a predetermined limiting time, and outputs a command which changes the predetermined limiting time depending on the field current. Accordingly, a temperature rise of the machine is suppressed and limiting of the field current can be released as needed.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: March 25, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Akita, Masato Mori, Kenji Nakajima, Mitsunori Tabata
  • Patent number: 8665222
    Abstract: A handwriting-input device and method capable of inputting a mixture of a character and a graphic without feeling discomfort even when an input area is physically limited. A handwriting-input device including, on a display screen, a normalized pencraft input area for inputting a pencraft desired to be normalized to be input and a pencraft arrangement area for inputting a pencraft that is not normalized and normalizing the pencraft to display it, at least includes: coordinate input means to obtain coordinate position information input by an input medium; and input area judgment means to judge which of the normalized pencraft input area and the pencraft arrangement area the pencraft is input in, based on the coordinate position information, wherein the pencraft can be input based on a judgment result in the input area judgment means.
    Type: Grant
    Filed: April 5, 2005
    Date of Patent: March 4, 2014
    Assignee: Fujitsu Limited
    Inventor: Kenji Nakajima
  • Publication number: 20140021782
    Abstract: A power supply system includes an electric storage device, a connecting terminal area, a main energization line, a sub-energization line, a first energization switching unit for switching between an energized state and a non-energized state of an energization line of the main energization line connecting the electric storage device and a loading apparatus, a second energization switching unit for switching between an energized state and a non-energized state of an energization line of the main energization line connecting a branched part and the connecting terminal area, a third energization switching unit for switching between an energized state and a non-energized state of an energization line of the main energization line connecting the second energization switching unit and the connecting terminal area, and a control device that detects switching states of the first, second and third energization switching units and that controls their switching operations.
    Type: Application
    Filed: April 5, 2012
    Publication date: January 23, 2014
    Applicant: DENSO CORPORATION
    Inventors: Gentaro Omura, Takahiro Chuman, Kenji Nakajima
  • Patent number: 8582888
    Abstract: According to an aspect of an embodiment, a method of detecting boundary line information contained in image information comprising a plurality of pixels in either one of first and second states, comprising: detecting a first group of pixels in the first state disposed continuously in said image information to determine first line information and detecting a second group of pixels in the first state disposed adjacently with each other and surrounded by pixels in the second state to determine edge information based on the contour of the second group of pixels; and determining the boundary line information on the basis of the information of the relation of relative position of the line information and the edge information and the size of the first and second group of pixels.
    Type: Grant
    Filed: February 14, 2008
    Date of Patent: November 12, 2013
    Assignee: Fujitsu Limited
    Inventors: Hiroshi Tanaka, Kenji Nakajima, Akihiro Minagawa, Hiroaki Takebe, Katsuhito Fujimoto
  • Publication number: 20130245911
    Abstract: A vehicle controller includes a wheel speed sensor, a skid sensor, an upper limit calculator, and a motive power controller. The wheel speed sensor is configured to detect rotational speed of driving wheels. The skid sensor is configured to determine whether or not the driving wheels are skidding based on an output of the wheel speed sensor. The upper limit calculator is configured to calculate an upper limit of rotational speed of the driving wheels if the skid sensor determines that the driving wheels are skidding. The motive power controller is configured to control motive power output from the driving source so that rotational speed of the driving wheels is equal to or smaller than the upper limit calculated by the upper limit calculator.
    Type: Application
    Filed: February 27, 2013
    Publication date: September 19, 2013
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Kenji NAKAJIMA, Youji YASUOKA, Masafumi AMANO, Takayuki YAMASAKI, Kazuhiro NAKANO
  • Publication number: 20130093366
    Abstract: To provide an upper limit of a generated voltage or generated torque, to thereby prevent the occurrence of an overvoltage or excessive torque during power generation, a control selection section (308) chooses and outputs a minimum value between a control output of a generated voltage control section (306) for controlling a field current so that a B-terminal voltage of a polyphase AC generator-motor coincides with a generated voltage command and a control output of a generated torque control section (307) for controlling, based on the B-terminal voltage and a rotation speed, the field current so that generated torque of the polyphase AC generator-motor coincides with a generated torque command.
    Type: Application
    Filed: April 10, 2012
    Publication date: April 18, 2013
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kenji NAKAJIMA, Masato MORI, Kenichi AKITA, Mitsunori TABATA
  • Patent number: 8397847
    Abstract: In an electric power converter for a vehicle which is connected to an alternating-current generator for a vehicle and performs synchronous rectification, switching mistakes are reduced and efficiency is improved by setting an optimal control allowance time in generating a switching timing signal from a diode ON signal. A control allowance according to the operating state of a generator can be determined by obtaining a control allowance time as a sum of a control delay time which is constant irrespective of the operating state of the generator, and an allowance time which varies depending on the operating state of the generator. Thereby, optimal switching timing is obtained and the reduction of switching mistakes and an improvement in efficiency are performed.
    Type: Grant
    Filed: October 20, 2010
    Date of Patent: March 19, 2013
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsunori Tabata, Masato Mori, Kenji Nakajima, Keinichi Akita
  • Patent number: 8339074
    Abstract: Generation voltage control or generation torque control is performed as suitable control based on an external command or a load of a generator motor, to thereby prevent a rapid change of a generation torque or excessive power generation. A power converter control apparatus includes: a power conversion unit including a bridge circuit for controlling energization of an armature winding and a field circuit for controlling energization of a field winding; and a control device including B-terminal voltage detection means, field current detection means, generation voltage control means, generation torque control means, and control selection means. The control selection means selects the one of the generation voltage control means and the generation torque control means based on one of a command from an outside and a load of the generator motor.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: December 25, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Nakajima, Masato Mori, Kenichi Akita, Mitsunori Tabata
  • Patent number: 8334680
    Abstract: Provided is a field winding type generator-motor capable of minimizing cost increase and structure modification while preventing a failure due to a temperature rise, without mounting a temperature sensor. The field winding type generator-motor according to the present invention includes: a dynamo-electric machine that has a field winding; a field current detecting section for detecting field current; a field current restriction deciding section for deciding whether or not the decision value has reached a predetermined decision threshold value by calculating a decision value based on the field current detected by the field current detecting section; and a field current controller for controlling the field current flowing in the field winding so that the field current is restricted to a predetermined permissible value in a case where the field current restriction deciding section decides that the decision value has reached the predetermined decision threshold value.
    Type: Grant
    Filed: November 16, 2009
    Date of Patent: December 18, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Akita, Kenji Nakajima, Masato Mori
  • Publication number: 20120293139
    Abstract: A field winding type rotary electric machine includes: a controller; a field current integration portion provided in the controller to calculate an integral value by integrating an excessive field current exceeding a field current threshold; a field current limiting portion provided in the controller and carrying out limiting processing to limit a field current to or below a predetermined value when the integral value reaches an integral value threshold defined as a reference value at or above which the field current is limited; a controller power supply connection switch switched ON and OFF for power feeding to the controller; a controller power supply connection determination portion switching ON and OFF the controller power supply connection switch; and a power feeding ON state maintaining portion maintaining an ON state of the power feeding to the controller from start to end of the limiting processing by the field current limiting portion.
    Type: Application
    Filed: December 16, 2011
    Publication date: November 22, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kenichi AKITA, Kenji NAKAJIMA, Masato MORI, Mitsunori TABATA
  • Publication number: 20120262130
    Abstract: A power converter control apparatus includes a power converter part having a bridge circuit formed of a switching element and a field circuit controlling conduction of a field winding in an AC generator, and a control apparatus part having a field current detector, a temperature detector detecting a temperature of a generator part, the power converter part, or the control apparatus part, a field current instruction computation portion computing a field current instruction value of the generator, a temperature rise suppression portion computing a generated current suppression value on the basis of an output of the temperature detector and computing a field current suppression value on the basis of the computed generated current suppression value, a field current instruction selection portion selecting the field current instruction value or the field current suppression value whichever is the smaller, and a field current control portion controlling a field current.
    Type: Application
    Filed: October 11, 2011
    Publication date: October 18, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kenji NAKAJIMA, Masato MORI, Kenichi AKITA, Mitsunori TABATA
  • Publication number: 20120261916
    Abstract: A power-generation motor control system is a control system that controls a power-generation motor provided with an armature and a magnetic-field winding, and is characterized in that when the power-generation motor is operated as a motor, before a power source energizes the armature, a preliminary excitation current, with the value of which the induction voltage across the armature does not exceed the voltage of the power source, is applied to the magnetic-field winding in accordance with the rotation speed of the power-generation motor so that preliminary excitation of the power-generation motor is performed.
    Type: Application
    Filed: October 17, 2011
    Publication date: October 18, 2012
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Mitsunori TABATA, Masato MORI, Kenji NAKAJIMA, Kenichi AKITA