Patents by Inventor Fuyuki Maehara

Fuyuki Maehara 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: 20140368171
    Abstract: A vehicle power generation control device receives a first limit value related to restriction of an excitation current, which flows to a field winding of a vehicle power generator, when the first limit value is transmitted from an external device. By the vehicle power generation control device, a second limit value related to restriction of the excitation current is determined to be a control value for the excitation current. The second limit value is held in an own vehicle power generation control device. By the vehicle power generation control device, the first limit value is determined to be the control value, instead of the second limit value being the control value, when the first limit value is received. Based on the control value, the vehicle power generation control device controls the excitation current flowing to the field winding.
    Type: Application
    Filed: June 18, 2014
    Publication date: December 18, 2014
    Inventor: Fuyuki MAEHARA
  • Patent number: 8164313
    Abstract: A power generation controlling device for vehicle includes a communication controlling circuit, a power generation voltage and excitation current controlling circuit, and a communication frame processing circuit. The communication controlling circuit communicates with an ECU using a communication frame. The power generation voltage and excitation current controlling circuit controls power generation based on power generation control information in the received communication frame. The communication frame processing circuit decodes contents of power generation control information (i.e., signal switching data) included in the communication frame based on a signal switching bit in the same communication frame. Two types of contents or more that are switched based on the signal switching bit are assigned to the power generation control information in the communication frame.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: April 24, 2012
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara
  • Patent number: 7948216
    Abstract: A control apparatus controls power generation of an electric generator and communicates with an external control apparatus. The control apparatus includes: a control circuit that controls the power generation of the electric generator according to a command signal transmitted from the external control apparatus; means for reseting the control circuit; and means for informing the external control apparatus of a power generation condition of the electric generator by transmitting a condition signal, the condition signal indicating both the power generation condition of the electric generator and information on whether a reset of the control circuit is made by the reseting means. With such a configuration, when the control circuit is reset due to, for example, noises, the control apparatus can reliably inform the external control apparatus of the reset of the control circuit.
    Type: Grant
    Filed: January 28, 2008
    Date of Patent: May 24, 2011
    Assignee: Denso Corporation
    Inventors: Tadatoshi Asada, Fuyuki Maehara
  • Patent number: 7683588
    Abstract: A device for controlling vehicle power generation that controls duty cycle of an excitation winding in a vehicle power generator and controls an output voltage from the vehicle power generator to a predetermined value includes a power generation controlling circuit that, when the output voltage from the vehicle power generator is less than the predetermined value, gradually increases the value of a gradual excitation duty and gradually increases the excitation current, the gradual excitation duty being a limit value for increasing and decreasing an excitation drive duty intermittently controlling the electrification of the excitation winding, and in an opposite situation, gradually decreases a value of the excitation drive duty and gradually decreases the excitation current. The power generation controlling circuit changes the rate at which the value of the gradual excitation duty is decreased.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: March 23, 2010
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara
  • Publication number: 20090195223
    Abstract: A power generation controlling device for vehicle includes a communication controlling circuit, a power generation voltage and excitation current controlling circuit, and a communication frame processing circuit. The communication controlling circuit communicates with an ECU using a communication frame. The power generation voltage and excitation current controlling circuit controls power generation based on power generation control information in the received communication frame. The communication frame processing circuit decodes contents of power generation control information (i.e., signal switching data) included in the communication frame based on a signal switching bit in the same communication frame. Two types of contents or more that are switched based on the signal switching bit are assigned to the power generation control information in the communication frame.
    Type: Application
    Filed: February 3, 2009
    Publication date: August 6, 2009
    Applicant: DENSO CORPORATION
    Inventor: Fuyuki Maehara
  • Patent number: 7528585
    Abstract: The vehicle-use power generation control apparatus regulates an output voltage of a vehicle generator driven by a vehicle engine at a set value by on/off controlling an excitation current flowing through an excitation winding of the vehicle generator The vehicle-use power generation control apparatus includes a rotation detecting circuit detecting a rotational speed of the vehicle generator, and an excitation current control circuit reducing, when the rotation detecting circuit detects decrease of the rotational speed, the excitation current at a rate depending on a rate of the decrease of the rotational speed detected by the rotation detecting circuit.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: May 5, 2009
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara
  • Publication number: 20090039838
    Abstract: A device for controlling vehicle power generation that controls duty cycle of an excitation winding in a vehicle power generator and controls an output voltage from the vehicle power generator to a predetermined value includes a power generation controlling circuit that, when the output voltage from the vehicle power generator is less than the predetermined value, gradually increases the value of a gradual excitation duty and gradually increases the excitation current, the gradual excitation duty being a limit value for increasing and decreasing an excitation drive duty intermittently controlling the electrification of the excitation winding, and in an opposite situation, gradually decreases a value of the excitation drive duty and gradually decreases the excitation current. The power generation controlling circuit changes the rate at which the value of the gradual excitation duty is decreased.
    Type: Application
    Filed: August 6, 2008
    Publication date: February 12, 2009
    Applicant: DENSO CORPORATION
    Inventor: Fuyuki Maehara
  • Patent number: 7423351
    Abstract: The vehicle-generator control device for controlling an output voltage of a vehicle generator by on/off-controlling an excitation current flowing into an excitation winding of the vehicle generator, includes an excitation current detecting circuit detecting an excitation current flowing into the excitation winding, and a computation circuit having a first function of correcting the excitation current detected by the excitation current detecting circuit on the basis of a current flowing into an electrical load applied with the output voltage of the vehicle generator, and a second function of calculating an output current of the vehicle generator on the basis of the excitation current.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: September 9, 2008
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara
  • Publication number: 20080179890
    Abstract: A control apparatus controls power generation of an electric generator and communicates with an external control apparatus. The control apparatus includes: a control circuit that controls the power generation of the electric generator according to a command signal transmitted from the external control apparatus; means for reseting the control circuit; and means for informing the external control apparatus of a power generation condition of the electric generator by transmitting a condition signal, the condition signal indicating both the power generation condition of the electric generator and information on whether a reset of the control circuit is made by the reseting means. With such a configuration, when the control circuit is reset due to, for example, noises, the control apparatus can reliably inform the external control apparatus of the reset of the control circuit.
    Type: Application
    Filed: January 28, 2008
    Publication date: July 31, 2008
    Applicant: Denso Corporation
    Inventors: Tadatoshi Asada, Fuyuki Maehara
  • Patent number: 7394227
    Abstract: A vehicle power generation control apparatus has a power supply circuit, a rotation detecting circuit, an exciting current detecting circuit, a torque detecting/maximum exciting current determining circuit, and an exciting current control circuit. The rotation detecting circuit detects a rotation speed of a generator (or vehicle alternator) and the exciting current detecting circuit detects an exciting current flowing through an exciting winding of the generator. The torque detecting/maximum exciting current determining circuit calculates a power generation torque of the generator based on the output voltage, the exciting current, the rotation speed, and calculates an inertia torque of the generator based on a change rate of the rotation speed.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: July 1, 2008
    Assignee: Denso Corporation
    Inventors: Tadashi Uematsu, Tadatoshi Asada, Fuyuki Maehara
  • Patent number: 7373919
    Abstract: An electric power generation control system has an electric power generation amount determining section for determining an electric power generation request amount of a vehicle alternator by monitoring vehicle conditions, an electric power generation amount increase judgment section for judging presence/absence of an electric power generation amount increase request to the vehicle alternator based on change of the electric power generation request amount in passage of time, an idle state judgment section for judging whether or not a vehicle engine falls in idle operation state, and an electric power generation amount suppressing control section for suppressing an electric power generation amount of the vehicle alternator. In the idle operation state of the vehicle engine and the presence of the electric power generation amount increase request, the electric power generation amount suppressing control section halts the control of suppressing the electric power generation of the vehicle alternator.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: May 20, 2008
    Assignee: Denso Corporation
    Inventors: Tadatoshi Asada, Fuyuki Maehara
  • Patent number: 7358705
    Abstract: An apparatus for controlling power generation of a generator has a voltage detector and a power controller. The voltage detector detects a voltage of electric power generated in the generator. When receiving a first power control signal, the power controller controls the generator to maintain the detected voltage at a first target value. When receiving a second power control signal, the power controller controls the generator such that the power controller suppresses the power generation of the generator based on a difference between a value of the detected voltage and a second target value lower than the first target value so as to maintain the detected voltage at a predetermined value lower than the first target value. Therefore, even when the power generation is suppressed, pulsation of the generated electric power can be appropriately restrained.
    Type: Grant
    Filed: February 23, 2006
    Date of Patent: April 15, 2008
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara
  • Patent number: 7288922
    Abstract: A control apparatus for a vehicle generator includes a switch, a regulator, a fault condition detector, and a PWM signal generator. The switch is selectively turned on and off so as to intermittently excite the generator. The regulator controls on/off operation of the switch so as to bring an output of the generator into agreement with a target value. The fault condition detector detects a fault condition of the generator. The PWM signal generator generates and outputs a PWM signal that has a duty determined as a function of a duty of the on/off operation of the switch and a frequency determined based on if the fault condition of the generator is detected by the fault condition detector. Consequently, the control apparatus can inform an external control apparatus of the duty of the on/off operation of the switch and the fault condition of the generator with the single PWM signal.
    Type: Grant
    Filed: April 24, 2006
    Date of Patent: October 30, 2007
    Assignee: Denso Corporation
    Inventors: Fuyuki Maehara, Kazuyuki Watanabe
  • Publication number: 20070247119
    Abstract: The vehicle-use power generation control apparatus regulates an output voltage of a vehicle generator driven by a vehicle engine at a set value by on/off controlling an excitation current flowing through an excitation winding of the vehicle generator The vehicle-use power generation control apparatus includes a rotation detecting circuit detecting a rotational speed of the vehicle generator, and an excitation current control circuit reducing, when the rotation detecting circuit detects decrease of the rotational speed, the excitation current at a rate depending on a rate of the decrease of the rotational speed detected by the rotation detecting circuit.
    Type: Application
    Filed: April 11, 2007
    Publication date: October 25, 2007
    Applicant: DENSO CORPORATION
    Inventor: Fuyuki Maehara
  • Publication number: 20070227499
    Abstract: An electric power generation control system has an electric power generation amount determining section for determining an electric power generation request amount of a vehicle alternator by monitoring vehicle conditions, an electric power generation amount increase judgment section for judging presence/absence of an electric power generation amount increase request to the vehicle alternator based on change of the electric power generation request amount in passage of time, an idle state judgment section for judging whether or not a vehicle engine falls in idle operation state, and an electric power generation amount suppressing control section for suppressing an electric power generation amount of the vehicle alternator. In the idle operation state of the vehicle engine and the presence of the electric power generation amount increase request, the electric power generation amount suppressing control section halts the control of suppressing the electric power generation of the vehicle alternator.
    Type: Application
    Filed: March 12, 2007
    Publication date: October 4, 2007
    Applicant: DENSO CORPORATION
    Inventors: Tadatoshi Asada, Fuyuki Maehara
  • Patent number: 7235952
    Abstract: A generator control apparatus, for controlling electrical generation operation of a vehicle alternator, has a LAN circuit and a dedicated communication circuit, respectively communicating with an external control apparatus (e.g., engine ECU) via a LAN and via a dedicated signal line. When a selection signal is transmitted from the external control apparatus, designating a specific signal to be transmitted to or from the generator control apparatus, communication of that signal is performed via the dedicated signal line, enabling TDM communication of plural signals via the LAN concurrent with direct communication of a specific signal via the dedicated signal line.
    Type: Grant
    Filed: December 8, 2004
    Date of Patent: June 26, 2007
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara
  • Patent number: 7227272
    Abstract: A control apparatus such as an ECU, that controls the generator of a vehicle, measures the engine rotation speed and generator rotation speed while the engine is idling, and calculates and stores the ratio of the speed values. Thereafter when the vehicle is being driven and the current value of generator rotation speed is required, it is calculated based on the stored ratio value and the currently measured speed of the engine. The processing load on the ECU is thereby reduced, since generator rotation speed measurement processing is performed only in the idling condition.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: June 5, 2007
    Assignee: Denso Corporation
    Inventors: Tadatoshi Asada, Fuyuki Maehara
  • Publication number: 20070085511
    Abstract: A vehicle power generation control apparatus has a power supply circuit, a rotation detecting circuit, an exciting current detecting circuit, a torque detecting/maximum exciting current determining circuit, and an exciting current control circuit. The rotation detecting circuit detects a rotation speed of a generator (or vehicle alternator) and the exciting current detecting circuit detects an exciting current flowing through an exciting winding of the generator. The torque detecting/maximum exciting current determining circuit calculates a power generation torque of the generator based on the output voltage, the exciting current, the rotation speed, and calculates an inertia torque of the generator based on a change rate of the rotation speed.
    Type: Application
    Filed: September 28, 2006
    Publication date: April 19, 2007
    Applicant: DENSO CORPORATION
    Inventors: Tadashi Uematsu, Tadatoshi Asada, Fuyuki Maehara
  • Publication number: 20070085512
    Abstract: The vehicle-generator control device for controlling an output voltage of a vehicle generator by on/off-controlling an excitation current flowing into an excitation winding of the vehicle generator, includes an excitation current detecting circuit detecting an excitation current flowing into the excitation winding, and a computation circuit having a first function of correcting the excitation current detected by the excitation current detecting circuit on the basis of a current flowing into an electrical load applied with the output voltage of the vehicle generator, and a second function of calculating an output current of the vehicle generator on the basis of the excitation current.
    Type: Application
    Filed: October 10, 2006
    Publication date: April 19, 2007
    Applicant: DENSO CORPORATION
    Inventor: Fuyuki Maehara
  • Patent number: 7183749
    Abstract: A generator control system of a vehicle generator includes a switching element which turns on or off field current, a field current detecting circuit, a calculating circuit which calculates an average value of the field current when the switching element turns on according to an amount of the detected field current, and a switch control circuit which cyclically controls the switching element according to the average value and a limit value of the field current.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: February 27, 2007
    Assignee: Denso Corporation
    Inventor: Fuyuki Maehara