Patents by Inventor Takao Muramatsu

Takao Muramatsu 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: 9862301
    Abstract: A vehicular rear panel with a new configuration is provided. The vehicular rear panel according to an aspect of the present disclosure is made of a resin material and disposed on a rear vehicle body part. The vehicular rear panel includes a light guiding unit configured to guide light from the light source along an extending direction of the vehicular rear panel and a light emitting unit configured to emit light in the light guiding unit to a rear side of a vehicle.
    Type: Grant
    Filed: July 22, 2015
    Date of Patent: January 9, 2018
    Assignee: Koito Manufacturing Co., Ltd.
    Inventors: Kenji Yamada, Masaaki Nakabayashi, Koji Uchino, Manabu Maeda, Noriaki Ito, Norimasa Yamamoto, Asami Nakada, Yuji Sakurai, Hiroya Koizumi, Tsukasa Tokida, Takao Muramatsu, Tomoaki Otani, Motohiro Komatsu, Akihiro Matsumoto, Takashi Terayama, Hiroki Ishibashi
  • Publication number: 20170282786
    Abstract: A blade receives light emitted from a light source and repeats a predetermined periodic motion to scan the front of a vehicle with reflected light of the emitted light. A position detector generates a position detection signal S4 indicating a timing at which a predetermined reference point of the blade passes a predetermined position. Based on the position detection signal S4, a period calculator calculates a period Tp of the periodic motion of the blade. A light intensity calculator receives light-distribution-pattern information S3 to be formed in front of the vehicle and calculates light intensity to be generated by the light source at each time based on the position detection signal S4 and the period Tp. A driver turns on a semiconductor light source so as to obtain the light intensity calculated by the light intensity calculator at each time.
    Type: Application
    Filed: June 22, 2017
    Publication date: October 5, 2017
    Applicant: Koito Manufacturing Co., Ltd.
    Inventors: Takeshi TODA, Kentarou MURAKAMI, Masayasu ITO, Takao MURAMATSU, Hidetada TANAKA, Satoshi YAMAMURA
  • Patent number: 9776559
    Abstract: In one embodiment of the vehicular display system, the drawing unit operates when the vehicle speed is within a predetermined low speed area, starts an operation thereof when the vehicle speed becomes above a lower limit of the low speed area, and stops the operation thereof when the vehicle speed exceeds an upper limit of the low speed area.
    Type: Grant
    Filed: April 6, 2016
    Date of Patent: October 3, 2017
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Michihiko Hayakawa, Takao Muramatsu, Naoki Sugiura, Syouhei Yanagidu, Satoshi Kikuchi, Hiroaki Hara, Takayoshi Ishizuka, Hidetada Tanaka, Takeshi Masuda
  • Patent number: 9648679
    Abstract: A lighting circuit, which is mounted in a vehicle lamp, can change the luminance at high speeds. The lighting circuit is used together with a semiconductor light source and makes up a vehicle lamp. A switching converter supplies power to the semiconductor light source. A converter controller controls the switching converter. A current detection circuit detects a current IDRV which is supplied from the switching converter to the semiconductor light source. A hysteresis comparator compares the detected current value with an upper threshold voltage and a lower threshold voltage and generates a control pulse according to the results of the comparison. A threshold voltage generating circuit receives a variable control voltage which indicates a target amount of a current and generates the upper threshold voltage and the lower threshold voltage according to the control voltage.
    Type: Grant
    Filed: October 2, 2015
    Date of Patent: May 9, 2017
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Kentarou Murakami, Takao Muramatsu
  • Patent number: 9637048
    Abstract: In the event that a predetermined illuminance is obtained by illuminating a certain area with light of a first light quantity, an illumination control system illuminates the area with light of a second light quantity which is larger than the first light quantity at a period, and at periods which follow the period, the illumination control system illuminates the area with light of a third light quantity of light which is smaller than the first light quantity.
    Type: Grant
    Filed: April 22, 2015
    Date of Patent: May 2, 2017
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Yuichi Shibata, Satoshi Yamamura, Takao Muramatsu
  • Patent number: 9598000
    Abstract: A vehicle lamp system includes a camera which generates image information in a front region, a controller which generates a light distribution command for instructing a light distribution pattern based on the image information, a headlight which irradiates the front region such that the instructed light distribution pattern is obtained, and a position calibrator which detects a positional deviation between the camera and the headlight. The position calibrator detects a reference object based on the image information and measures a luminance of the reference object, and when there is a certain difference between a luminance of the reference object obtained from one light distribution pattern and a luminance of the reference object obtained from another light distribution pattern in which a light quantity of only a part is different from the one light distribution pattern, detects the positional deviation using a position of the part.
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: March 21, 2017
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Masayasu Ito, Takao Muramatsu, Yuta Maruyama
  • Patent number: 9550448
    Abstract: The invention relates to a light distribution control method and a light distribution control device in which plural illumination regions are arranged in the left-right direction and illuminated by a headlamp in an ADB light distribution pattern, and vehicle positions of a vehicle ahead are detected and selected ones of the plural illumination regions are reduced in light quantity according to the detected vehicle positions. In this method and device, corrected vehicle positions are set that are obtained by adding margins to the detected vehicle positions in the left and right directions, respectively, and compared with the plural illumination regions. Illumination regions where the vehicle ahead exists are reduced in light quantity.
    Type: Grant
    Filed: July 9, 2014
    Date of Patent: January 24, 2017
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Hidetada Tanaka, Takeshi Masuda, Motohiro Komatsu, Takao Muramatsu
  • Publication number: 20160297357
    Abstract: In one embodiment of the vehicular display system, the drawing unit operates when the vehicle speed is within a predetermined low speed area, starts an operation thereof when the vehicle speed becomes above a lower limit of the low speed area, and stops the operation thereof when the vehicle speed exceeds an upper limit of the low speed area.
    Type: Application
    Filed: April 6, 2016
    Publication date: October 13, 2016
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Michihiko HAYAKAWA, Takao MURAMATSU, Naoki SUGIURA, Syouhei YANAGIDU, Satoshi KIKUCHI, Hiroaki HARA, Takayoshi ISHIZUKA, Hidetada TANAKA, Takeshi MASUDA
  • Publication number: 20160264042
    Abstract: A vehicle lamp system includes a camera which generates image information in a front region, a controller which generates a light distribution command for instructing a light distribution pattern based on the image information, a headlight which irradiates the front region such that the instructed light distribution pattern is obtained, and a position calibrator which detects a positional deviation between the camera and the headlight. The position calibrator detects a reference object based on the image information and measures a luminance of the reference object, and when there is a certain difference between a luminance of the reference object obtained from one light distribution pattern and a luminance of the reference object obtained from another light distribution pattern in which a light quantity of only a part is different from the one light distribution pattern, detects the positional deviation using a position of the part.
    Type: Application
    Filed: March 11, 2016
    Publication date: September 15, 2016
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Masayasu Ito, Takao Muramatsu, Yuta Maruyama
  • Publication number: 20160238210
    Abstract: A vehicle lamp control system is provided which can not only restrict a semiconductor light emitting element from being deteriorated or damaged by sunlight and but also maintain an illumination efficiency of the semiconductor light emitting element. The vehicle lamp control system includes a projection lens, semiconductor light emitting elements disposed near a rear focal point of the projection lens and emit light towards the projection lens, a movable shade which can move between a shading position where the movable shade cuts off light emitted from the semiconductor light emitting elements to be incident on the projection lens and a non-shading position where the movable shade does not cut off light emitting elements to be incident on the projection lens, and a headlamp control unit which executes a control in which the movable shade is moved to the shading position with the semiconductor light emitting elements left switched off.
    Type: Application
    Filed: September 25, 2014
    Publication date: August 18, 2016
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Takeshi MASUDA, Michihiko HAYAKAWA, Takao MURAMATSU, Misako NAKAZAWA, Hidetada TANAKA, Yuichi SHIBATA
  • Patent number: 9386646
    Abstract: There is provided a driving device which is used together with a light source including a plurality of light emitting units connected in series to configure a vehicle lamp. The driving device includes a current source which is configure to supply a drive current to the light source, and N bypass circuits which are provided in parallel to N light emitting units, respectively. Each of the bypass circuits includes a bypass transistor which is provided in parallel to a corresponding light emitting unit, a feedback capacitor which is provided between a gate and a drain of the bypass transistor, and a gate drive circuit which is configured to supply a drive voltage between the gate and a source of the bypass transistor according to a control signal.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: July 5, 2016
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Masayasu Ito, Takao Muramatsu, Syouhei Yanagidu
  • Publication number: 20160167566
    Abstract: The invention relates to a light distribution control method and a light distribution control device in which plural illumination regions are arranged in the left-right direction and illuminated by a headlamp in an ADB light distribution pattern, and vehicle positions of a vehicle ahead are detected and selected ones of the plural illumination regions are reduced in light quantity according to the detected vehicle positions. In this method and device, corrected vehicle positions are set that are obtained by adding margins to the detected vehicle positions in the left and right directions, respectively, and compared with the plural illumination regions. Illumination regions where the vehicle ahead exists are reduced in light quantity.
    Type: Application
    Filed: July 9, 2014
    Publication date: June 16, 2016
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Hidetada TANAKA, Takeshi MASUDA, Motohiro KOMATSU, Takao MURAMATSU
  • Patent number: 9320107
    Abstract: The present disclosure provides a vehicular lamp including bypass circuits parallel to light emitting devices to precisely cope with an abnormality of the bypass circuit side. The vehicular lamp includes: one or more bypass units connected in parallel to at least a part of a plurality of light emitting devices to form a bypass route of the emission driving current so that the light emitting device is turned OFF according to a bypass control signal, or to cut off the bypass route; abnormality detecting units configured to generate state signals each of which indicates an normal state or an abnormal state of each of the bypass units; and a control unit configured to control the formation of the bypass route. When the generated state signal indicates that each of the bypass units is abnormal, supply of the emission driving current from the light source power supply is reduced or stopped.
    Type: Grant
    Filed: December 3, 2014
    Date of Patent: April 19, 2016
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Toda Takeshi, Takao Muramatsu, Tsuchiya Toshiyuki, Masayasu Ito
  • Publication number: 20160096467
    Abstract: A lighting circuit, which is mounted in a vehicle lamp, can change the luminance at high speeds. The lighting circuit is used together with a semiconductor light source and makes up a vehicle lamp. A switching converter supplies power to the semiconductor light source. A converter controller controls the switching converter. A current detection circuit detects a current IDRV which is supplied from the switching converter to the semiconductor light source. A hysteresis comparator compares the detected current value with an upper threshold voltage and a lower threshold voltage and generates a control pulse according to the results of the comparison. A threshold voltage generating circuit receives a variable control voltage which indicates a target amount of a current and generates the upper threshold voltage and the lower threshold voltage according to the control voltage.
    Type: Application
    Filed: October 2, 2015
    Publication date: April 7, 2016
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Kentarou Murakami, Takao Muramatsu
  • Patent number: 9265109
    Abstract: A semiconductor light source control device includes a driver circuit, which generates a drive current Iout flowing through a plurality of LEDs connected in series and which performs control such that the amount of the drive current is brought close to a target value, and bypass switches, which are on-off controlled by a control signal, the bypass switches being connected in parallel with the corresponding LEDs. The semiconductor light source control device is configured such that when the control signal indicates the off-state of the bypass switches, a voltage across the corresponding LEDs is clamped at an upper limit by using the bypass switches.
    Type: Grant
    Filed: May 10, 2013
    Date of Patent: February 16, 2016
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Takao Muramatsu, Masayasu Ito, Kazuki Saito
  • Patent number: 9198247
    Abstract: A current controller 42 compares a first coil current IL1 flowing in an output inductor L1 with a first upper threshold value and a first lower threshold value. A current limiter 44 compares a second coil current IL2 flowing in an input inductor L2 with a second upper threshold value and a second lower threshold value. A duty controller 46 (i) switches a switching transistor M1 based on the first coil current in a cycle where the first coil current IL1 exceeds the first upper threshold value before the second coil current IL2, exceeds the second upper threshold value. According to the current controller 42, it is possible to stabilize an output current and to limit a current.
    Type: Grant
    Filed: February 12, 2015
    Date of Patent: November 24, 2015
    Assignee: KOITO MANUFACTURING CO., LTD.
    Inventors: Masayasu Ito, Takao Muramatsu, Syouhei Yanagizu
  • Publication number: 20150321599
    Abstract: A vehicular rear panel with a new configuration is provided. The vehicular rear panel according to an aspect of the present disclosure is made of a resin material and disposed on a rear vehicle body part. The vehicular rear panel includes a light guiding unit configured to guide light from the light source along an extending direction of the vehicular rear panel and a light emitting unit configured to emit light in the light guiding unit to a rear side of a vehicle.
    Type: Application
    Filed: July 22, 2015
    Publication date: November 12, 2015
    Inventors: Kenji YAMADA, Masaaki NAKABAYASHI, Koji UCHINO, Manabu MAEDA, Noriaki ITO, Norimasa YAMAMOTO, Asami NAKADA, Yuji SAKURAI, Hiroya KOIZUMI, Tsukasa TOKIDA, Takao MURAMATSU, Tomoaki OTANI, Motohiro KOMATSU, Akihiro MATSUMOTO, Takashi TERAYAMA, Hiroki ISHIBASHI
  • Publication number: 20150307018
    Abstract: In the event that a predetermined illuminance is obtained by illuminating a certain area with light of a first light quantity, an illumination control system illuminates the area with light of a second light quantity which is larger than the first light quantity at a period, and at periods which follow the period, the illumination control system illuminates the area with light of a third light quantity of light which is smaller than the first light quantity.
    Type: Application
    Filed: April 22, 2015
    Publication date: October 29, 2015
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Yuichi SHIBATA, Satoshi YAMAMURA, Takao MURAMATSU
  • Publication number: 20150264754
    Abstract: There is provided a driving device which is used together with a light source including a plurality of light emitting units connected in series to configure a vehicle lamp. The driving device includes a current source which is configure to supply a drive current to the light source, and N bypass circuits which are provided in parallel to N light emitting units, respectively. Each of the bypass circuits includes a bypass transistor which is provided in parallel to a corresponding light emitting unit, a feedback capacitor which is provided between a gate and a drain of the bypass transistor, and a gate drive circuit which is configured to supply a drive voltage between the gate and a source of the bypass transistor according to a control signal.
    Type: Application
    Filed: March 13, 2015
    Publication date: September 17, 2015
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Masayasu ITO, Takao MURAMATSU, Syouhei YANAGIDU
  • Publication number: 20150230302
    Abstract: A current controller 42 compares a first coil current IL1 flowing in an output inductor L1 with a first upper threshold value and a first lower threshold value. A current limiter 44 compares a second coil current IL2 flowing in an input inductor L2 with a second upper threshold value and a second lower threshold value. A duty controller 46 (i) switches a switching transistor M1 based on the first coil current in a cycle where the first coil current IL1 exceeds the first upper threshold value before the second coil current IL2, exceeds the second upper threshold value. According to the current controller 42, it is possible to stabilize an output current and to limit a current.
    Type: Application
    Filed: February 12, 2015
    Publication date: August 13, 2015
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventors: Masayasu ITO, Takao MURAMATSU, Syouhei YANAGIZU