Patents by Inventor Koichi Toyama

Koichi Toyama 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: 20030006706
    Abstract: In a discharge lamp apparatus, a casing of an electronic controller unit for a discharge lamp is comprised of a resin casing and a metal casing and accommodates therein circuit components for generating a voltage supplied to the discharge lamp. The resin casing couples with and contacts with the connector part of the discharge lamp. A power MOS transistor is attached to the metal casing through a plate member made of an insulating material. With this arrangement, heat generated by the discharge lamp is less likely to transfer from the resin casing to the metal casing, and heat generated by the power MOS transistor is efficiently radiated from the metal casing to the outside.
    Type: Application
    Filed: May 17, 2002
    Publication date: January 9, 2003
    Inventors: Hironao Yamaguchi, Koichi Toyama
  • Patent number: 6291945
    Abstract: A lighting device for a discharge lamp includes a power supplying circuit for supplying electric power to the discharge lamp. A current sensing circuit is operative for sensing a lamp current which flows through the discharge lamp. A control circuit is operative for enabling the power supplying circuit to supply one of a direct-current electric power and a low-frequency electric power to the discharge lamp during a time interval in start of the discharge lamp. The control circuit is also operative for adjusting a duration time of supply of a one-polarity electric power to the discharge lamp in accordance with a magnitude of the lamp current sensed by the current sensing circuit. Further, the control circuit is operative for enabling the power supplying circuit to supply an alternating-current electric power to the discharge lamp after the time interval elapses.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: September 18, 2001
    Assignee: Nippondenso Co., Ltd.
    Inventors: Koichi Toyama, Koichi Kato, Kenji Aida
  • Patent number: 5910712
    Abstract: A discharge lamp driver is configured so that it can be operationally tested using a substitute impedance instead of a discharge lamp. The time required to functionally test the driver circuit with such a substituted non-discharge lamp load is considerably less than if an actual discharge lamp is used for such testing.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: June 8, 1999
    Assignee: Denso Corporation
    Inventor: Koichi Toyama
  • Patent number: 5880563
    Abstract: When a discharge lamp repeatedly flickers out after illuminating for a long period of time because the same discharge lamp is nearing the end of its usage lifetime, a stored voltage of a capacitor rises gradually every time the discharge lamp flickers out. When the stored voltage of the same capacitor becomes no less than a predetermined voltage, a comparator generates a high level voltage which actuates a transistor. The transistor then terminates the operations of a PWM circuit to deactuate the discharge lamp.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: March 9, 1999
    Assignee: Denso Corporation
    Inventors: Koichi Toyama, Koichi Kato, Kenji Aida
  • Patent number: 5751121
    Abstract: In a discharge bulb control, a time constant circuit comprised of a capacitor and a resistor is used to determine an electric power to be supplied to a discharge bulb. During a warm-up period of the discharge bulb, the capacitor is charged to produce a voltage which varies, toward a predetermined voltage, with an electric current flowing thereto so that the electric power is increased gradually. After the warm-up control, the time constant for charging the capacitor is reduced to maintain the capacitor voltage at the predetermined voltage. Even with the current leakage occurring in the capacitor after the warm-up control, the electric power is controlled by the predetermined voltage which is not influenced by the current leakage. Thus, the electric power applied to the discharge bulb after the warm-up control can advantageously be maintained at the required level.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: May 12, 1998
    Assignee: Denso Corporation
    Inventors: Koichi Toyama, Noboru Yamamoto
  • Patent number: 5706185
    Abstract: DC/DC converter 31 boosts an output voltage of a battery 1 having a negative terminal grounded to a vehicle body, and supplies a boosted voltage to a discharge lamp 4 interposed between a positive output terminal and a negative output terminal of battery 1. A lamp current detecting resistance 35, connected in series with discharge lamp 4, detects a lamp current flowing through discharge lamp 4. Lamp voltage detecting resistances 33 and 34 detect a lamp voltage applied to discharge lamp 4. An electric power of DC/DC converter 31 is controlled by lamp power calculating circuit 36 and DC/DC converter drive circuit 37 based on the lamp current detected by lamp current detecting resistance 35 and the lamp voltage detected by lamp voltage detecting resistances 33 and 34. Discharge lamp 4 and lamp current detecting resistance 35 are connected at a connecting point "a" which is grounded.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: January 6, 1998
    Assignee: Nippondenso Co., Ltd.
    Inventors: Koichi Toyama, Koichi Kato, Kenji Aida
  • Patent number: 5608815
    Abstract: An image testing device captures an image of a test object using a TV camera and raster-scans the image to search the test object for a scratch or spot. The device protects its test precision from being deteriorated by lowered brightness of an illuminator and properly maintains the illuminator by outputting an alarm on detecting a lowering of the illuminator. To realize the capabilities of the image testing device, it comprises a brightness measure circuit, a general determination circuit, etc. The brightness measure circuit receives a multivalued gray image signal or image data from the frame memory through a switching unit, obtains an average value of picture elements in a brightness measure area in a test object image, and outputs it as a measured brightness signal. The general determination circuit corrects, in proportion to a measured brightness a binarization threshold for use in detecting a picture element indicating a defect.
    Type: Grant
    Filed: November 15, 1994
    Date of Patent: March 4, 1997
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Koichi Toyama, Tatsuo Yamamura
  • Patent number: 5600208
    Abstract: A discharge lamp unit which does not require enlargement of the discharge lamp and can still prevent application of a high voltage to a cap holder when the lamp is not connected includes a core of a high-voltage transformer inside a cap of the discharge lamp. Both a primary coil and a secondary coil of the high-voltage transformer are provided around a cap holder of the discharge lamp power supply. The cap of discharge lamp is inserted into the cap holder of the discharge lamp power supply to provide an electromagnetic link between the primary coil and the secondary coil of the high-voltage transformer.
    Type: Grant
    Filed: October 18, 1995
    Date of Patent: February 4, 1997
    Assignee: Nippondenso Co., Ltd.
    Inventors: Kouichi Katou, Koichi Toyama, Kenji Aida
  • Patent number: 5404854
    Abstract: A knocking vibration detecting unit (1) and a knock deciding unit (c) are integrated, and the communications of a knock intensity between the knock deciding unit (c) and an engine controlling microcomputer (7) are carried out in combination of a change from the previous value of a signal line level. In the engine controlling microcomputer (7), the ignition timing is controlled by a predetermined retard angle in case of combination of no change of the present read signal line level from the previous signal line level.Thus, an internal combustion engine is prevented from any damage by relieving a failure without fail when a signal line (10) is troubled, while minimizing the influences of noises and reducing the space and size of an ECU.
    Type: Grant
    Filed: October 8, 1993
    Date of Patent: April 11, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventors: Koichi Kamabora, Koji Sakakibara, Hiroshi Haraguchi, Toshiharu Iwata, Koichi Toyama, Toshihito Nonaka
  • Patent number: 5216369
    Abstract: An ignition detecting device for use in an internal combustion engine. An ignition surge current detector detects an ignition surge current due to capacitive discharge of the ignition coil. A comparator compares an output voltage detected by the ignition surge current detector with a predetermined reference voltage to detect accurately occurrence or non-occurrence of ignition spark.
    Type: Grant
    Filed: April 20, 1992
    Date of Patent: June 1, 1993
    Assignee: Nippondenso Co., Ltd.
    Inventor: Koichi Toyama
  • Patent number: 4809668
    Abstract: An ignition system for and internal combustion engine ignition coil energization time is controlled in accordance with operating conditions. First and second sections with respective constant angles in an ignition cycle are defined. An integrating circuit integrates in one direction in the second section of a preceding ignition cycle of the angle signal, and in the other direction in the first section of the next ignition cycle. When the integration value reaches a first predetermined value, an energization start signal is generated. An ignition coil begins to be energized at the time of generation of the energization start signal or at the shift of the angle signal from the first section to the second section, whichever arrives earlier, and the energization is stopped when the angle signal shifts from the second to first section.
    Type: Grant
    Filed: March 26, 1987
    Date of Patent: March 7, 1989
    Assignee: Nippondenso Co., Ltd.
    Inventors: Koichi Toyama, Ko Narita, Toshihito Nonaka
  • Patent number: 4773380
    Abstract: A current flowing time period control system for an ignition coil of an internal combustion engine is disclosed in which a current flowing time period setting circuit sets the time period for supplying the primary current of the ignition coil and an output signal of the current flowing time period setting circuit is amplified by a drive circuit and supplied to a power transistor, whereby the primary current of the ignition coil is intermittented to control the ignition operation.
    Type: Grant
    Filed: January 6, 1987
    Date of Patent: September 27, 1988
    Assignee: Nippondenso Co., Ltd.
    Inventors: Ko Narita, Koichi Toyama, Takeshi Matsui
  • Patent number: 4741319
    Abstract: An ignition system for internal combustion engines is constructed so that, in response to each ignition signal from ignition signal generating means, through a predetermined angle before a succeeding ignition timing, a storage quantity of storing means is gradually increased from an initial value and then it is gradually decreased, and a time point when the storage quantity of the storing means has been decreased to reach the initial value is detected by first storage quantity detecting means to thereby turn on a power transistor for turning on and off a primary current of an ignition coil at that time point, and further the fact that the storage quantity of the storing means has been decreased to reach a set value larger than the initial value is detected by second storage quantity detecting means to thereby change a decrease rate of the storage quantity of the storing means.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: May 3, 1988
    Assignee: Nippondenso Co. LTD.
    Inventors: Ko Narita, Koichi Toyama, Toshihito Nonaka
  • Patent number: 4572151
    Abstract: An ignition system for an internal combustion engine includes an ignition coil having a plurality of primary coils corresponding respectively to individual cylinders of the internal combustion engine, a basic ignition signal detector for producing basic ignition signals in synchronism with the engine rotation, an ignition control circuit for receiving the basic ignition signals and producing an ignition control signal having a controlled predetermined pulse width, a basic cylinder discriminating signal detector for producing a basic cylinder discriminating signal having a period twice that of the basic ignition signals in synchronism with the engine rotation, a cylinder discriminating signal forming logic circuit for receiving the ignition control signal and the basic cylinder discriminating signal and forming a cylinder discriminating signal by changing-over the basic cylinder discriminating signal in accordance with a state thereof, at a transition point of a waveform of the ignition control signal which co
    Type: Grant
    Filed: July 27, 1984
    Date of Patent: February 25, 1986
    Assignee: Nippondenso Co., Ltd.
    Inventor: Koichi Toyama
  • Patent number: 4475520
    Abstract: A contactless erroneous ignition prevention type ignition system for internal combustion engines, in which the energization of the ignition coil is held regardless of an input signal for a predetermined time period after starting the energization. At a first predetermined time after the output signal of a rotational signal generator corresponding to the rotational speed of the internal combustion engine exceeds a reference level, the energization of the ignition coil is started, and the energization of the ignition coil is maintained regardless of the output signal of the rotational signal generator until a second predetermined time. The charging timing of a capacitor of a frequency-voltage converter circuit for controlling the dwell angle of the ignition coil is controlled according to the first and second predetermined times.
    Type: Grant
    Filed: July 27, 1982
    Date of Patent: October 9, 1984
    Assignee: Nippondenso Co., Ltd.
    Inventors: Koichi Toyama, Tomoatsu Makino
  • Patent number: 4167927
    Abstract: In a contactless ignition control system having a dwell time control circuit for an internal combustion engine, there is provided a speed responsive bias voltage circuit, a bias voltge switching circuit and a wave shaping circuit. The speed responsive bias voltage changes the switching level of the wave shaping circuit, thereby elongating the dwell time of the current flowing through an ignition coil.In the dwell time control, when the ignition timing comes, the bias voltage switching circuit prevents application of the speed responsive bias voltage so that the ignition timing is made irrespective of the speed responsive bias voltage.
    Type: Grant
    Filed: September 22, 1977
    Date of Patent: September 18, 1979
    Assignee: Nippondenso Co., Ltd.
    Inventors: Youichi Mikami, Koichi Toyama, Yasushi Sugiura
  • Patent number: 4094556
    Abstract: An improved anti-skid system for a vehicle which effectively utilizes an approximated slip ratio between vehicle or body velocity and wheel velocity to generate a brake release signal for a brake release valve but without actually utilizing a vehicle or body velocity detector. Storage apparatus is used to store a reference signal representing vehicle velocity but actually corresponding to a present or just past maximum value of wheel velocity. Control apparatus is then utilized for removing energy from the storage apparatus at a controlled predetermined rate chosen to approximate the expected vehicle deceleration (but without using an actual vehicle or body deceleration detector) such that the reference signal (capacitor voltage) will continue to accurately represent approximate vehicle velocities even during periods of deceleration.
    Type: Grant
    Filed: March 11, 1971
    Date of Patent: June 13, 1978
    Assignee: Nippondenso Kabushiki Kaisha
    Inventors: Atutoshi Okamoto, Koichi Taniguchi, Yoshiaki Nakano, Koichi Toyama
  • Patent number: 4033634
    Abstract: An antiskid control device for vehicles, comprising a timer circuit for producing a timing signal in synchronism with the extinction of a release signal for a skid control, apparatus for rapidly increasing the braking pressure applied to the wheel in response to said timing signal coming from the timer circuit, and correcting apparatus for increasing the braking pressure increasing rate when a large amount of friction is present between the wheel and the road surface, said antiskid control device being able to hold the fluctuation of the braking pressure within a narrow range to prevent unnecessary vibrations of the vehicle at the time of braking due to the fact that the braking pressure increasing rate is changed when the braking pressure is reapplied to the wheel, and being able to control the braking operation at all times in a manner best suited to the various road surface conditions encountered so that a skid of the vehicle is prevented from occurring and the braking distance is reduced greatly, due to t
    Type: Grant
    Filed: June 18, 1975
    Date of Patent: July 5, 1977
    Assignees: Nippondenso Co., Ltd, Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Hiroshi Arai, Takahiro Nogami, Akio Sugiura, Atutoshi Okamoto, Koichi Toyama
  • Patent number: 4027926
    Abstract: An anti-skid control system for preventing skidding of a vehicle caused by the braking of the vehicle while it is in motion in the system when a vehicle speed signal generated from vehicle speed detecting apparatus becomes lower than a predetermined value, discriminating apparatus generates a discrimination signal and the braking pressure applied to the wheel is modulated through limiting apparatus including a logical gate and controlled by the discrimination signal. On the other hand, when the vehicle body speed becomes lower than a predetermined value, the generation of the discrimination signal is prevented by a deceleration sensor, thus suitably controlling the braking pressure in accordance with the surface conditions of the road.
    Type: Grant
    Filed: April 30, 1975
    Date of Patent: June 7, 1977
    Assignees: Nippondenso Co., Ltd., Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Hiroshi Arai, Akira Nakamura, Akio Sugiura, Atutoshi Okamoto, Koichi Toyama