Patents by Inventor Tomoaki Serizawa

Tomoaki Serizawa 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: 6844681
    Abstract: A vehicle light apparatus includes: a power consuming portion provided in parallel with a group of light emitting elements for causing a total power value including power consumed by the lamp to become a normal power value, a breakage detecting portion for detecting a breakage with respect to the group of light emitting elements, and a control portion for controlling power supply to the group of light emitting elements, wherein in the event that a breakage of the group of light emitting elements is detected by the breakage detecting portion, a power supply to the lamp including the group of broken light emitting elements is stopped or power supplied to the lamp is reduced by the control portion. By providing the power consuming portion, the load characteristic can be made constant, and power consumption can be reduced when a breakage of the light emitting element is detected.
    Type: Grant
    Filed: June 2, 2003
    Date of Patent: January 18, 2005
    Assignee: Koito Manufacturing Co., Ltd.
    Inventors: Tomoaki Serizawa, Kimiaki Ishikawa, Tadayuki Okuda, Masayasu Ito, Taketoshi Fujigaya, Michio Arai, Hitoshi Takeda
  • Patent number: 6715909
    Abstract: A vehicle lamp including a light-emitting diode and a lighting circuit for the light-emitting diode, a lamp chamber defined by a lamp body and a lens that covers the front of the lamp body, an LED circuit board which is disposed in the lamp chamber and on which the light-emitting diode and the lighting circuit are provided, and a cord for connecting the LED circuit board to an electric power supply; and in addition a limiting resistor for limiting a supply current for the light-emitting diode being provided on a part of the cord that is located outside the lamp chamber.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: April 6, 2004
    Assignee: Koito Manufacturing Co., Ltd.
    Inventor: Tomoaki Serizawa
  • Publication number: 20030227257
    Abstract: A vehicle light apparatus includes: a power consuming means provided in parallel with a group of light emitting elements for causing a total power value including power consumed by the lamp to become a normal power value, a breakage detecting means for detecting a breakage with respect to the group of light emitting elements, and a control means for controlling power supply to the group of light emitting elements, wherein in the event that a breakage of the group of light emitting elements is detected by the breakage detecting means, a power supply to the lamp including the group of broken light emitting elements is stopped or power supplied to the lamp is reduced by the control means. By providing the power consuming means, the load characteristic can be made constant, and power consumption can be reduced when a breakage of the light emitting element is detected.
    Type: Application
    Filed: June 2, 2003
    Publication date: December 11, 2003
    Inventors: Tomoaki Serizawa, Kimiaki Ishikawa, Tadayuki Okuda, Masayasu Ito, Taketoshi Fujigaya, Michio Arai, Hitoshi Takeda
  • Publication number: 20030067787
    Abstract: A vehicle lamp including a light-emitting diode and a lighting circuit for the light-emitting diode, a lamp chamber defined by a lamp body and a lens that covers the front of the lamp body, an LED circuit board which is disposed in the lamp chamber and on which the light-emitting diode and the lighting circuit are provided, and a cord for connecting the LED circuit board to an electric power supply; and in addition a limiting resistor for limiting a supply current for the light-emitting diode being provided on a part of the cord that is located outside the lamp chamber.
    Type: Application
    Filed: October 3, 2002
    Publication date: April 10, 2003
    Applicant: Koito Manufacturing Co., Ltd.
    Inventor: Tomoaki Serizawa
  • Patent number: 6406173
    Abstract: A vehicle lamp comprising a lamp body and a light source unit. The lamp body defines a lamp chamber in cooperation with a lens mounted to a front opening of the lamp body. The light source unit in the lamp chamber includes a plurality of light-emitting elements, a base supporting the light-emitting elements, and at least one electric cord. Holders for the light-emitting elements of the light source unit are fit to the base of the light source unit, and the light-emitting elements are electrically connected to the electric cord by holding the electric cord between one of the holders and one of the light-emitting elements.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: June 18, 2002
    Assignee: Koito Manufacturing Company, Ltd.
    Inventors: Tomoaki Serizawa, Tsutomu Machida
  • Publication number: 20020034081
    Abstract: A vehicle lamp having a light source formed from a plurality of LEDs. The vehicle lamp has a plurality of Fresnel lenses for converting light from the LEDs to parallel light, and are provided in front of the light source. A diffusion lens having a plurality of diffusion lens elements is provided in front of the plurality of Fresnel lenses. The vehicle lamp also has a condenser lens that receives light from the plurality of diffusion lens, and the condenser lens is provided in front of the diffusion lens. Light from each LED is converted to parallel light, diffused by the diffusion lens and then concentrated by the condenser lens before being emitted in the forward direction of the lighting device. The maximum diffusion angle and luminous intensity distribution of the forward emission light of the lighting device can readily be set at target values by properly adjusting the shapes of the respective diffusion lens elements and the condenser lens.
    Type: Application
    Filed: September 18, 2001
    Publication date: March 21, 2002
    Applicant: KOITO MANUFACTURING CO., LTD.
    Inventor: Tomoaki Serizawa
  • Patent number: 5488546
    Abstract: In a color changing lamp equipped with a bulb 4 emitting a color of light, a glove with a different color from the color is selectively located on the covering position and exposure position of the bulb 4 in order to emit the different color of light. The current supply for the bulb 4 is stopped while the glove is selectively moved, thereby preventing different colors of light in a mixed state from being emitted on the way of exchange.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: January 30, 1996
    Assignee: Koito Manufacturing Co., Ltd.
    Inventors: Osamu Sato, Toshihisa Hayami, Hideki Ohashi, Makoto Izawa, Tomoaki Serizawa, Hideki Uchida
  • Patent number: 5479323
    Abstract: A vehicular cornering lamp system which can be adapted to all types and models of vehicles without having to change the correspondence of the illuminating angle with specific characteristics of the vehicle. The angular velocity of the vehicle is detected when the vehicle is traveling on a curve by an angular velocity sensor. Pulses from a distance sensor are counted to detect the vehicle's velocity. Angular velocity data and vehicle velocity data are latched by respective latch circuits. The reciprocal of the turning radius is calculated directly by dividing the angular velocity data by the vehicle velocity data in a divider. There is carried out an arithmetic operation of calculating the reciprocal of the turning radius after calculating the turning radius by dividing the vehicle velocity data by the angular velocity data. The illuminating angle can be approximated as a simple inverse function with respect to the turning radius.
    Type: Grant
    Filed: November 15, 1993
    Date of Patent: December 26, 1995
    Assignee: Koito Manufacturing Co., Ltd.
    Inventors: Hiroki Shibata, Takayuki Unno, Tomoaki Serizawa
  • Patent number: 5410456
    Abstract: A vehicular cornering lamp system which reduces spark noise generated by a motor thereof, reduces wear of parts such as the brushes and commutator of the motor, and improves the rate of use of the power voltage of the system and thereby generates sufficient torque to rotate the motor. An illumination direction control circuit generates voltages to be applied to the two terminals of the motor according to differences between the output voltage of a lamp illumination angle sensor and the output voltage of a steering sensor.
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: April 25, 1995
    Assignee: Koito Manufacturing Co., Ltd.
    Inventors: Hiroki Shibata, Tomoaki Serizawa