Patents by Inventor Keiji Shigeoka

Keiji Shigeoka 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: 9621046
    Abstract: In a power converter, a reference signal generator generates a reference signal with a predetermined period. A current detector detects a current flowing in the converter. When a value of the detected current is larger than a value of a predetermined current command, a reset signal generator generates a reset signal. A driving unit drives a switch. The switch is turned on, and subsequently is turned off: (i) in synchronization with the reference signal when the reset signal is not outputted before the reference signal is outputted; and (ii) in synchronization with the reset signal when the reset signal is outputted before the reference signal is outputted. However, the switch is turned off in synchronization with the reset signal during a predetermined time including a first predetermined time before an output timing of the reference signal and a second predetermined time after the output timing of the reference signal.
    Type: Grant
    Filed: January 17, 2013
    Date of Patent: April 11, 2017
    Assignee: DENSO CORPORATION
    Inventors: Hirofumi Kinjo, Keiji Shigeoka, Yuji Hayashi, Kimikazu Nakamura
  • Patent number: 9413566
    Abstract: A signal transmission circuit includes a transceiver, an impedance adjustment circuit, a first control circuit and a second control circuit. The impedance adjustment circuit realizes a low impedance state and a normal state of the transmission line. The first control circuit controls the impedance adjustment circuit to realize the low impedance state for a fixed period that is shorter than a width of one bit, when a change of a signal level on the transmission line is detected. The second control circuit controls the impedance adjustment circuit according to a transmission data transmitted from the transceiver, when detecting that a communication frame wins an arbitration by comparing the transmission data and the received data, to realize the low impedance state in an entire period where the signal level on the transmission line is recessive until transmission of the communication frame ends.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: August 9, 2016
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Hiroyuki Mori, Keiji Shigeoka, Yoshifumi Kaku, Shogo Akasaki
  • Patent number: 9270505
    Abstract: Each of nodes in a communication system includes a pull-up circuit connected between a power source and a transmission line and a switching portion connecting and disconnecting the transmission line and a ground line. One of the nodes is a master node, and the others of the nodes are slave nodes. The driver circuits are driven so that the master node constantly outputs the transmission code of logic 1 and the slave node outputting the transmission code of logic 0 extends the width of the low level of the transmission code of logic 1 on the transmission line. The master node further includes a current limiting section limiting an electric current that flows to the transmission line via the pull-up circuit based on at least a signal level of the transmission line.
    Type: Grant
    Filed: March 26, 2015
    Date of Patent: February 23, 2016
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Hiroyuki Mori, Keiji Shigeoka, Hideki Kashima, Tomohisa Kishigami
  • Publication number: 20160036604
    Abstract: A signal transmission circuit includes a transceiver, an impedance adjustment circuit, a first control circuit and a second control circuit. The impedance adjustment circuit realizes a low impedance state and a normal state of the transmission line. The first control circuit controls the impedance adjustment circuit to realize the low impedance state for a fixed period that is shorter than a width of one bit, when a change of a signal level on the transmission line is detected. The second control circuit controls the impedance adjustment circuit according to a transmission data transmitted from the transceiver, when detecting that a communication frame wins an arbitration by comparing the transmission data and the received data, to realize the low impedance state in an entire period where the signal level on the transmission line is recessive until transmission of the communication frame ends.
    Type: Application
    Filed: July 29, 2015
    Publication date: February 4, 2016
    Inventors: Hiroyuki MORI, Keiji SHIGEOKA, Yoshifumi KAKU, Shogo AKASAKI
  • Patent number: 9184736
    Abstract: A current mode controlled power converter controllable in a digitally processing current mode even during an on time. In the power converter, each control period based on a reference signal includes a slope calculation period in which a slope compensation signal for the control period is calculated by a slope compensation unit. During each slope calculation period, the slope compensation unit negates the slope compensation signal calculated previous to the control period including the slope calculation period, and a reset signal generation unit compares a current detection signal detected by a current detection unit with a current instruction set to an error signal generated by an error signal generation unit to generate a reset signal.
    Type: Grant
    Filed: August 30, 2013
    Date of Patent: November 10, 2015
    Assignee: DENSO CORPORATION
    Inventors: Hirofumi Kinjou, Yuji Hayashi, Keiji Shigeoka, Kimikazu Nakamura
  • Publication number: 20150295738
    Abstract: Each of nodes in a communication system includes a pull-up circuit connected between a power source and a transmission line and a switching portion connecting and disconnecting the transmission line and a ground line. One of the nodes is a master node, and the others of the nodes are slave nodes. The driver circuits are driven so that the master node constantly outputs the transmission code of logic 1 and the slave node outputting the transmission code of logic 0 extends the width of the low level of the transmission code of logic 1 on the transmission line. The master node further includes a current limiting section limiting an electric current that flows to the transmission line via the pull-up circuit based on at least a signal level of the transmission line.
    Type: Application
    Filed: March 26, 2015
    Publication date: October 15, 2015
    Inventors: Hiroyuki MORI, Keiji SHIGEOKA, Hideki KASHIMA, Tomohisa KISHIGAMI
  • Patent number: 9071149
    Abstract: A DC-DC converter generates PWM signals PWM1H, PWM1L on the basis of a reference signal CLK1 to drive switching elements connected in series. When generating a reset signal RST, the converter generates PWM signals PWM2H, PWM2L on the basis of the reset signal RST. When generating no reset signal, the converter generates the PWM signals PWM2H, PWM2L on the basis of a reference signal CLK2 in order to drive other switching elements connected in series. The converter generates the reset signal RST at an optional timing to the reference signal CLK1. The reference signal CLK2 is brought forward from the reference signal CLK1 by ?T1. The PWM signals PWM1H, PWM1L are different in timing from the PWM signals PWM2H, PWM2L. This makes it possible to avoid the switching elements diagonally arranged from being simultaneously turned on and off, and suppress a switching loss, and to increase an efficiency of the converter.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: June 30, 2015
    Assignee: DENSO CORPORATION
    Inventors: Hirofumi Kinjou, Keiji Shigeoka, Yuji Hayashi, Kenji Tomita, Kimikazu Nakamura
  • Publication number: 20140062558
    Abstract: A current mode controlled power converter controllable in a digitally processing current mode even during an on time. In the power converter, each control period based on a reference signal includes a slope calculation period in which a slope compensation signal for the control period is calculated by a slope compensation unit. During each slope calculation period, the slope compensation unit negates the slope compensation signal calculated previous to the control period including the slope calculation period, and a reset signal generation unit compares a current detection signal detected by a current detection unit with a current instruction set to an error signal generated by an error signal generation unit to generate a reset signal.
    Type: Application
    Filed: August 30, 2013
    Publication date: March 6, 2014
    Applicant: DENSO CORPORATION
    Inventors: Hirofumi KINJOU, Yuji HAYASHI, Keiji SHIGEOKA, Kimikazu NAKAMURA
  • Publication number: 20130336014
    Abstract: A DC-DC converter generates PWM signals PWM1H, PWM1L on the basis of a reference signal CLK1 to drive switching elements connected in series. When generating a reset signal RST, the converter generates PWM signals PWM2H, PWM2L on the basis of the reset signal RST. When generating no reset signal, the converter generates the PWM signals PWM2H, PWM2L on the basis of a reference signal CLK2 in order to drive other switching elements connected in series. The converter generates the reset signal RST at an optional timing to the reference signal CLK1. The reference signal CLK2 is brought forward from the reference signal CLK1 by ?T1. The PWM signals PWM1H, PWM1L are different in timing from the PWM signals PWM2H, PWM2L. This makes it possible to avoid the switching elements diagonally arranged from being simultaneously turned on and off, and suppress a switching loss, and to increase an efficiency of the converter.
    Type: Application
    Filed: March 18, 2013
    Publication date: December 19, 2013
    Applicant: DENSO CORPORATION
    Inventors: Hirofumi KINJOU, Keiji SHIGEOKA, Yuji HAYASHI, Kenji TOMITA, Kimikazu NAKAMURA
  • Publication number: 20130300397
    Abstract: In a power converter, a reference signal generator generates a reference signal with a predetermined period. A current detector detects a current flowing in the converter. When a value of the detected current is larger than a value of a predetermined current command, a reset signal generator generates a reset signal. A driving unit drives a switch. The switch is turned on, and subsequently is turned off: (i) in synchronization with the reference signal when the reset signal is not outputted before the reference signal is outputted; and (ii) in synchronization with the reset signal when the reset signal is outputted before the reference signal is outputted. However, the switch is turned off in synchronization with the reset signal during a predetermined time including a first predetermined time before an output timing of the reference signal and a second predetermined time after the output timing of the reference signal.
    Type: Application
    Filed: January 17, 2013
    Publication date: November 14, 2013
    Inventors: Hirofumi KINJO, Keiji SHIGEOKA, Yuji HAYASHI, Kimikazu NAKAMURA
  • Patent number: 8412390
    Abstract: An information presentation device includes: a directional information obtaining element for obtaining directional information based on a signal from an enhancement device for safety or comfort of a passenger of a vehicle; an information presentation controller for generating a driving signal based on the directional information; and a stimulation element including multiple vibrators for generating a traveling wave of vibration in an in-vehicle element. A directionality of the traveling wave corresponds to the directional information. The stimulation element transmits the traveling wave to the passenger so that the passenger perceives the directionality of the traveling wave.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: April 2, 2013
    Assignees: DENSO CORPORATION, Nippon Soken, Inc.
    Inventors: Norio Sanma, Keiji Shigeoka, Sei Iguchi
  • Publication number: 20110035100
    Abstract: An information presentation device includes: a directional information obtaining element for obtaining directional information based on a signal from an enhancement device for safety or comfort of a passenger of a vehicle; an information presentation controller for generating a driving signal based on the directional information; and a stimulation element including multiple vibrators for generating a traveling wave of vibration in an in-vehicle element. A directionality of the traveling wave corresponds to the directional information. The stimulation element transmits the traveling wave to the passenger so that the passenger perceives the directionality of the traveling wave.
    Type: Application
    Filed: August 5, 2010
    Publication date: February 10, 2011
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Norio Sanma, Keiji Shigeoka, Sei Iguchi
  • Patent number: 7825765
    Abstract: In a DC to DC converter, first and second primary windings are magnetically coupled to a first secondary winding. Third and fourth primary windings are magnetically coupled to a second secondary winding. The first and second primary windings are magnetically coupled to the first secondary winding. The third and fourth primary windings are magnetically coupled to the second secondary winding. The first and third primary windings are coupled in series to form a first coil member. The second and fourth primary windings are coupled in series to form a second coil member. One end of the first coil member is coupled to the first positive power line. A first switching element is coupled between the first negative power line and the other end of the first coil member. A first capacitor is coupled between the first negative terminal and one end of the second coil member.
    Type: Grant
    Filed: July 27, 2009
    Date of Patent: November 2, 2010
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Tsuyoshi Yamashita
  • Patent number: 7738269
    Abstract: A switching device 30 and a related operating method are disclosed for generate a train of drive pulses under a basic pattern for a repetition cycle time T. The train of drive pulses has leading edges shifted from basic time periods T1 by shift amounts ?0 to ?02, respectively, which are different from each other, whereby switching frequencies, occurring based on the leading edges of the drive pulses, are spread. A spread frequency, which is a inverse number of the cycle time T of the basic pattern, is set to be higher than an audible frequency.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: June 15, 2010
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Shinya Goto, Koji Kawasaki, Keiji Shigeoka
  • Publication number: 20090290388
    Abstract: In a DC to DC converter, first and second primary windings are magnetically coupled to a first secondary winding. Third and fourth primary windings are magnetically coupled to a second secondary winding. The first and second primary windings are magnetically coupled to the first secondary winding. The third and fourth primary windings are magnetically coupled to the second secondary winding. The first and third primary windings are coupled in series to form a first coil member. The second and fourth primary windings are coupled in series to form a second coil member. One end of the first coil member is coupled to the first positive power line. A first switching element is coupled between the first negative power line and the other end of the first coil member. A first capacitor is coupled between the first negative terminal and one end of the second coil member.
    Type: Application
    Filed: July 27, 2009
    Publication date: November 26, 2009
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Tsuyoshi Yamashita
  • Patent number: 7589432
    Abstract: A switching device comprises a switching element, a setting member, and a control member. The switching element turns on/off in response to a drive signal, so as to control a controlled variable of a controlled system to a desired amount. The setting member sets the drive signal on the basis of both a desired duty to control the controlled variable, wherein the drive signal is set by repeating a basic pattern consisting of a plurality of intervals which are decided to remove overlaps, in a frequency spectrum, between or among switching frequencies produced based on an interval between start timings of the on operations and an interval between start timings of the off operations. The control member variably controls the switching element based on the drive signal.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: September 15, 2009
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Shinya Goto
  • Patent number: 7570501
    Abstract: In a DC to DC converter, first and second primary windings are magnetically coupled to a first secondary winding. Third and fourth primary windings are magnetically coupled to a second secondary winding. The first and second primary windings are magnetically coupled to the first secondary winding. The third and fourth primary windings are magnetically coupled to the second secondary winding. The first and third primary windings are coupled in series to form a first coil member. The second and fourth primary windings are coupled in series to form a second coil member. One end of the first coil member is coupled to the first positive power line. A first switching element is coupled between the first negative power line and the other end of the first coil member. A first capacitor is coupled between the first negative terminal and one end of the second coil member.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: August 4, 2009
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Tsuyoshi Yamashita
  • Publication number: 20080030293
    Abstract: In a DC to DC converter, first and second primary windings are magnetically coupled to a first secondary winding. Third and fourth primary windings are magnetically coupled to a second secondary winding. The first and second primary windings are magnetically coupled to the first secondary winding. The third and fourth primary windings are magnetically coupled to the second secondary winding. The first and third primary windings are coupled in series to form a first coil member. The second and fourth primary windings are coupled in series to form a second coil member. One end of the first coil member is coupled to the first positive power line. A first switching element is coupled between the first negative power line and the other end of the first coil member. A first capacitor is coupled between the first negative terminal and one end of the second coil member.
    Type: Application
    Filed: May 30, 2007
    Publication date: February 7, 2008
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Tsuyoshi Yamashita
  • Patent number: 7289338
    Abstract: In a DC to DC converter, a transformer circuit includes a primary winding and a secondary winding member composed of series-connected first to fourth secondary windings having one and the other ends. The one and the other ends of the series-connected first to fourth secondary windings are connected to a first output terminal. The first and second secondary windings are wound around a first magnetic path in opposite directions, and the third and fourth secondary windings are wound around a second magnetic path in opposite directions. A first rectifying element is connected between the second output terminal and a connection point between the first and second secondary windings. A second rectifying element is connected between the second output terminal and a connection point between the third and fourth secondary windings.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: October 30, 2007
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Yuji Hayashi, Tsuyoshi Yamashita
  • Patent number: 7269035
    Abstract: A switching device and a method of operating a switching power element are disclosed for generating a train of drive pulses (D1 to D32) in a basic pattern for a repetition cycle time (T to TF) having leading time intervals (Th1 to Th3, Th1? to Th3?), associated with leading edges (a1 to a32) of the drive pulses, and trailing time intervals (Tl1 to Tl3, Tl1? to Tl3?), associated with trailing edges (b1 to b32) of the drive pulses, which are different from each other, whereby switching frequencies and associated harmonics, resulting from the leading edges and the trailing edges of the drive pulses, are diffused. A diffusion frequency, representing an inverse number of the repetition cycle time for the basic pattern is set to be higher than an audible frequency.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: September 11, 2007
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Koji Kawasaki, Keiji Shigeoka, Shinya Goto